stray light reduction: Topics by WorldWideScience.org

Sample records for stray light reduction

Stray light reduction for Thomson scattering

NARCIS (Netherlands)

Bakker, L.P.; Kroesen, G.M.W.; Doebele, H.F.; Muraoka, K.

1999-01-01

In order to perform Thomson scattering in a gas discharge tube, the reduction of stray light is very important because of the very small Thomson cross-section. By introducing a sodium absorption cell as a notch filter, we can reduce the measured stray light considerably. Then we have to use a dye
Stray light analysis and control

CERN Document Server

Fest, Eric

2013-01-01

Stray light is defined as unwanted light in an optical system, a familiar concept for anyone who has taken a photograph with the sun in or near their camera's field of view. This book addresses stray light terminology, radiometry, and the physics of stray light mechanisms, such as surface roughness scatter and ghost reflections. The most-efficient ways of using stray light analysis software packages are included. The book also demonstrates how the basic principles are applied in the design, fabrication, and testing phases of optical system development.
Fast space-varying convolution using matrix source coding with applications to camera stray light reduction.

Science.gov (United States)

Wei, Jianing; Bouman, Charles A; Allebach, Jan P

2014-05-01

Many imaging applications require the implementation of space-varying convolution for accurate restoration and reconstruction of images. Here, we use the term space-varying convolution to refer to linear operators whose impulse response has slow spatial variation. In addition, these space-varying convolution operators are often dense, so direct implementation of the convolution operator is typically computationally impractical. One such example is the problem of stray light reduction in digital cameras, which requires the implementation of a dense space-varying deconvolution operator. However, other inverse problems, such as iterative tomographic reconstruction, can also depend on the implementation of dense space-varying convolution. While space-invariant convolution can be efficiently implemented with the fast Fourier transform, this approach does not work for space-varying operators. So direct convolution is often the only option for implementing space-varying convolution. In this paper, we develop a general approach to the efficient implementation of space-varying convolution, and demonstrate its use in the application of stray light reduction. Our approach, which we call matrix source coding, is based on lossy source coding of the dense space-varying convolution matrix. Importantly, by coding the transformation matrix, we not only reduce the memory required to store it; we also dramatically reduce the computation required to implement matrix-vector products. Our algorithm is able to reduce computation by approximately factoring the dense space-varying convolution operator into a product of sparse transforms. Experimental results show that our method can dramatically reduce the computation required for stray light reduction while maintaining high accuracy.
Identification and mitigation of stray laser light in the Thomson scattering system on the Madison Symmetric Torus (MST)

Energy Technology Data Exchange (ETDEWEB)

Jacobson, C. M., E-mail: cjacobson@wisc.edu; Borchardt, M. T.; Den Hartog, D. J.; Falkowski, A. F.; Morton, L. A.; Thomas, M. A. [Department of Physics, University of Wisconsin–Madison, 1150 University Avenue, Madison, Wisconsin 53706 (United States)

2016-11-15

The Thomson scattering diagnostic on the Madison Symmetric Torus (MST) records excessive levels of stray Nd:YAG laser light. Stray light saturates the 1064 nm spectral channel in all polychromators, which prevents absolute electron density measurements via Rayleigh scattering calibration. Furthermore, stray light contaminates adjacent spectral channels for r/a ≥ 0.75, which renders the diagnostic unable to make electron temperature measurements at these radii. In situ measurements of stray light levels during a vacuum vessel vent are used to identify stray light sources and strategies for reduction of stray light levels. Numerical modeling using Zemax OpticStudio supports these measurements. The model of the vacuum vessel and diagnostic includes synthetic collection optics to enable direct comparison of measured and simulated stray light levels. Modeling produces qualitatively similar stray light distributions to MST measurements, and quantifies the mitigation effects of stray light mitigation strategies prior to implementation.
Identification and mitigation of stray laser light in the Thomson scattering system on the Madison Symmetric Torus (MST)

International Nuclear Information System (INIS)

Jacobson, C. M.; Borchardt, M. T.; Den Hartog, D. J.; Falkowski, A. F.; Morton, L. A.; Thomas, M. A.

2016-01-01

The Thomson scattering diagnostic on the Madison Symmetric Torus (MST) records excessive levels of stray Nd:YAG laser light. Stray light saturates the 1064 nm spectral channel in all polychromators, which prevents absolute electron density measurements via Rayleigh scattering calibration. Furthermore, stray light contaminates adjacent spectral channels for r/a ≥ 0.75, which renders the diagnostic unable to make electron temperature measurements at these radii. In situ measurements of stray light levels during a vacuum vessel vent are used to identify stray light sources and strategies for reduction of stray light levels. Numerical modeling using Zemax OpticStudio supports these measurements. The model of the vacuum vessel and diagnostic includes synthetic collection optics to enable direct comparison of measured and simulated stray light levels. Modeling produces qualitatively similar stray light distributions to MST measurements, and quantifies the mitigation effects of stray light mitigation strategies prior to implementation.
Stray light characteristics of the diffractive telescope system

Science.gov (United States)

Liu, Dun; Wang, Lihua; Yang, Wei; Wu, Shibin; Fan, Bin; Wu, Fan

2018-02-01

Diffractive telescope technology is an innovation solution in construction of large light-weight space telescope. However, the nondesign orders of diffractive optical elements (DOEs) may affect the imaging performance as stray light. To study the stray light characteristics of a diffractive telescope, a prototype was developed and its stray light analysis model was established. The stray light characteristics including ghost, point source transmittance, and veiling glare index (VGI) were analyzed. During the star imaging test of the prototype, the ghost images appeared around the star image as the exposure time of the charge-coupled device improving, consistent with the simulation results. The test result of VGI was 67.11%, slightly higher than the calculated value 57.88%. The study shows that the same order diffraction of the diffractive primary lens and correcting DOE is the main factor that causes ghost images. The stray light sources outside the field of view can illuminate the image plane through nondesign orders diffraction of the primary lens and contributes to more than 90% of the stray light flux on the image plane. In summary, it is expected that these works will provide some guidance for optimizing the imaging performance of diffractive telescopes.
Influence of stray light for divertor spectroscopy in ITER

International Nuclear Information System (INIS)

Kajita, Shin; Veshchev, Evgeny; Lisgo, Steve; Barnsley, Robin; Morgan, Philip; Walsh, Michael; Ogawa, Hiroaki; Sugie, Tatsuo; Itami, Kiyoshi

2015-01-01

The influence of stray light in the divertor spectroscopy system in ITER is quantitatively investigated using a ray tracing simulation. Simulation results show that the stray light is negligible at positions in the divertor where the plasma emission is strong. However, it is also shown that the stray light can be significantly greater than the real signal if the plasma intensity is low. Deuterium and beryllium emissions are used for the assessment; for beryllium cases in particular, since the emission profile may be non-uniform in the divertor region, the influence of stray light can be non-negligible at some positions, e.g., above the divertor dome
ON THE INVERSION OF STOKES PROFILES WITH LOCAL STRAY-LIGHT CONTAMINATION

International Nuclear Information System (INIS)

Asensio Ramos, A.; Manso Sainz, R.

2011-01-01

Obtaining the magnetic properties of non-resolved structures in the solar photosphere is always challenging and problems arise because the inversion is carried out through the numerical minimization of a merit function that depends on the proposed model. We investigate the reliability of inversions in which the stray-light contamination is obtained from the same observations as a local average. In this case, we show that it is fundamental to include the covariance between the observed Stokes profiles and the stray-light contamination. The ensuing modified merit function of the inversion process penalizes large stray-light contaminations simply because of the presence of positive correlations between the observables and the stray light, fundamentally produced by spatially variable systematics. We caution that if the wrong merit function is used, artificially large stray-light contaminations might be inferred. Since this effect disappears if the stray-light contamination is obtained as an average over the full field of view, we recommend taking into account stray-light contamination using a global approach.
Stray light field dependence for large astronomical space telescopes

Science.gov (United States)

Lightsey, Paul A.; Bowers, Charles W.

2017-09-01

Future large astronomical telescopes in space will have architectures that expose the optics to large angular extents of the sky. Options for reducing stray light coming from the sky range from enclosing the telescope in a tubular baffle to having an open telescope structure with a large sunshield to eliminate solar illumination. These two options are considered for an on-axis telescope design to explore stray light considerations. A tubular baffle design will limit the sky exposure to the solid angle of the cone in front of the telescope set by the aspect ratio of the baffle length to Primary Mirror (PM) diameter. Illumination from this portion of the sky will be limited to the PM and structures internal to the tubular baffle. Alternatively, an open structure design will allow a large portion of the sky to directly illuminate the PM and Secondary Mirror (SM) as well as illuminating sunshield and other structure surfaces which will reflect or scatter light onto the PM and SM. Portions of this illumination of the PM and SM will be scattered into the optical train as stray light. A Radiance Transfer Function (RTF) is calculated for the open architecture that determines the ratio of the stray light background radiance in the image contributed by a patch of sky having unit radiance. The full 4π steradian of sky is divided into a grid of patches, with the location of each patch defined in the telescope coordinate system. By rotating the celestial sky radiance maps into the telescope coordinate frame for a given pointing direction of the telescope, the RTF may be applied to the sky brightness and the results integrated to get the total stray light from the sky for that pointing direction. The RTF data generated for the open architecture may analyzed as a function of the expanding cone angle about the pointing direction. In this manner, the open architecture data may be used to directly compare to a tubular baffle design parameterized by allowed cone angle based on the
Fast and accurate modeling of stray light in optical systems

Science.gov (United States)

Perrin, Jean-Claude

2017-11-01

The first problem to be solved in most optical designs with respect to stray light is that of internal reflections on the several surfaces of individual lenses and mirrors, and on the detector itself. The level of stray light ratio can be considerably reduced by taking into account the stray light during the optimization to determine solutions in which the irradiance due to these ghosts is kept to the minimum possible value. Unhappily, the routines available in most optical design software's, for example CODE V, do not permit all alone to make exact quantitative calculations of the stray light due to these ghosts. Therefore, the engineer in charge of the optical design is confronted to the problem of using two different software's, one for the design and optimization, for example CODE V, one for stray light analysis, for example ASAP. This makes a complete optimization very complex . Nevertheless, using special techniques and combinations of the routines available in CODE V, it is possible to have at its disposal a software macro tool to do such an analysis quickly and accurately, including Monte-Carlo ray tracing, or taking into account diffraction effects. This analysis can be done in a few minutes, to be compared to hours with other software's.
Usage of ray tracing transfer matrix to mitigate the stray light for ITER spectroscopy

International Nuclear Information System (INIS)

Kajita, S.; Veshchev, E.; Barnsley, R.; Walsh, M.

2016-01-01

Stray light formed by the reflection of photons on inner wall from a bright divertor region can be a serious issue in spectroscopic measurement systems in ITER. In this study, we propose a method to mitigate the influence of stray light using a ray tracing analysis. Usually, a ray tracing simulation requires a time consuming runs. We constructed transfer matrices based on the ray tracing simulation results and used them to demonstrate the influence of stray light. It is shown that the transfer matrix can be used to reconstruct the emission profile by considering the influence of the stray light without any additional ray tracing runs. Mitigation of the stray light in ITER divertor impurity monitor was demonstrated, and a method of prediction of the stray light level for the scrape off layer spectroscopy from divertor region was proposed. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
A high-power spatial filter for Thomson scattering stray light reduction

Science.gov (United States)

Levesque, J. P.; Litzner, K. D.; Mauel, M. E.; Maurer, D. A.; Navratil, G. A.; Pedersen, T. S.

2011-03-01

The Thomson scattering diagnostic on the High Beta Tokamak-Extended Pulse (HBT-EP) is routinely used to measure electron temperature and density during plasma discharges. Avalanche photodiodes in a five-channel interference filter polychromator measure scattered light from a 6 ns, 800 mJ, 1064 nm Nd:YAG laser pulse. A low cost, high-power spatial filter was designed, tested, and added to the laser beamline in order to reduce stray laser light to levels which are acceptable for accurate Rayleigh calibration. A detailed analysis of the spatial filter design and performance is given. The spatial filter can be easily implemented in an existing Thomson scattering system without the need to disturb the vacuum chamber or significantly change the beamline. Although apertures in the spatial filter suffer substantial damage from the focused beam, with proper design they can last long enough to permit absolute calibration.
[Influence of different multifocal intraocular lens concepts on retinal stray light parameters].

Science.gov (United States)

Ehmer, A; Rabsilber, T M; Mannsfeld, A; Sanchez, M J; Holzer, M P; Auffarth, G U

2011-10-01

Multifocal intraocular lenses (MIOL) are known to induce various photic phenomena depending on the optical principle. The aim of this study was to investigate the correlation between stray light measurements performed with the C-Quant (Oculus, Germany) and the results of a subjective patient questionnaire. In this study three different MIOLs were compared: AMO ReZoom (refractive design, n=10), AMO ZM900 (diffractive design, n=10) and Oculentis Mplus (near segment design, n=10). Cataract and refractive patients were enrolled in the study. Functional results were evaluated at least 3 months postoperatively followed by stray light measurements and a subjective questionnaire. Surgery was performed for all patients without complications. The three groups were matched for age, IOL power and corrected distance visual acuity (CDVA). Significantly different stray light (median) values log(s) were found (Kruskal-Wallis test, p<0.05): 1.12 log (refractive), 1.13 log (segment) and 1.28 log (diffractive). The subjective questionnaire did not show differences in glare perception but refractive MIOL patients noticed more halos surrounding light sources than the diffractive and segment MIOL patients. Stray light and subjective photopic phenomena do not show any basic correlation. Measurements in patients with refractive MIOLs showed less stray light than near segment or diffractive MIOLs. However, refractive MIOLs induced more halos compared to the other groups analyzed.
Pitfalls and artifacts in measuring absorption spectra and kinetics: the effect of stray light in the UV and red regions

International Nuclear Information System (INIS)

Czapski, Gideon; Ozeri, Yair; Goldstein, Sara

2005-01-01

Effects of stray light on absorption spectrum and kinetics are discussed. The extent of the stray light depends on the light source, monochromator, wavelength set by the instrument and the absorption of the sample at this wavelength. Effects of the stray light on the shape of the spectrum and the extinction coefficients are shown. Methods for determining the existence and extent of stray light are suggested and are especially relevant for studies using pulse radiolysis, flash photolysis, and stopped-flow techniques. The literature examples for artifacts due to stray light are presented for kinetics and absorption spectra
Carbon Nanotubes on Titanium Substrates for Stray Light Suppression

Science.gov (United States)

Hagopian, John; Getty, Stephanie; Quijada, Manuel

2011-01-01

A method has been developed for growing carbon nanotubes on a titanium substrate, which makes the nano tubes ten times blacker than the current state-of-the-art paints in the visible to near infrared. This will allow for significant improvement of stray light performance in scientific instruments, or any other optical system. Because baffles, stops, and tubes used in scientific observations often undergo loads such as vibration, it is critical to develop this surface treatment on structural materials. This innovation optimizes the carbon nano - tube growth for titanium, which is a strong, lightweight structural material suitable for spaceflight use. The steps required to grow the nanotubes require the preparation of the surface by lapping, and the deposition of an iron catalyst over an alumina stiction layer by e-beam evaporation. In operation, the stray light controls are fabricated, and nanotubes (multi-walled 100 microns in length) are grown on the surface. They are then installed in the instruments or other optical devices.
Comparison of stray light in spectrometer systems using a low cost monochromatic light source

DEFF Research Database (Denmark)

Thorseth, Anders; Lindén, Johannes; Dam-Hansen, Carsten

2014-01-01

We present an experimental setup that is under development for automated stray light characterization of spectrometers. The setup uses a tuneable monochromator which enables this characterization on relatively cost low equipment. We present the measured line spread functions for two spectrometers...
Stray light correction on array spectroradiometers for optical radiation risk assessment in the workplace

International Nuclear Information System (INIS)

Barlier-Salsi, A

2014-01-01

The European directive 2006/25/EC requires the employer to assess and, if necessary, measure the levels of exposure to optical radiation in the workplace. Array spectroradiometers can measure optical radiation from various types of sources; however poor stray light rejection affects their accuracy. A stray light correction matrix, using a tunable laser, was developed at the National Institute of Standards and Technology (NIST). As tunable lasers are very expensive, the purpose of this study was to implement this method using only nine low power lasers; other elements of the correction matrix being completed by interpolation and extrapolation. The correction efficiency was evaluated by comparing CCD spectroradiometers with and without correction and a scanning double monochromator device as reference. Similar to findings recorded by NIST, these experiments show that it is possible to reduce the spectral stray light by one or two orders of magnitude. In terms of workplace risk assessment, this spectral stray light correction method helps determine exposure levels, with an acceptable degree of uncertainty, for the majority of workplace situations. The level of uncertainty depends upon the model of spectroradiometers used; the best results are obtained with CCD detectors having an enhanced spectral sensitivity in the UV range. Thus corrected spectroradiometers require a validation against a scanning double monochromator spectroradiometer before using them for risk assessment in the workplace. (paper)
Stray light correction on array spectroradiometers for optical radiation risk assessment in the workplace.

Science.gov (United States)

Barlier-Salsi, A

2014-12-01

The European directive 2006/25/EC requires the employer to assess and, if necessary, measure the levels of exposure to optical radiation in the workplace. Array spectroradiometers can measure optical radiation from various types of sources; however poor stray light rejection affects their accuracy. A stray light correction matrix, using a tunable laser, was developed at the National Institute of Standards and Technology (NIST). As tunable lasers are very expensive, the purpose of this study was to implement this method using only nine low power lasers; other elements of the correction matrix being completed by interpolation and extrapolation. The correction efficiency was evaluated by comparing CCD spectroradiometers with and without correction and a scanning double monochromator device as reference. Similar to findings recorded by NIST, these experiments show that it is possible to reduce the spectral stray light by one or two orders of magnitude. In terms of workplace risk assessment, this spectral stray light correction method helps determine exposure levels, with an acceptable degree of uncertainty, for the majority of workplace situations. The level of uncertainty depends upon the model of spectroradiometers used; the best results are obtained with CCD detectors having an enhanced spectral sensitivity in the UV range. Thus corrected spectroradiometers require a validation against a scanning double monochromator spectroradiometer before using them for risk assessment in the workplace.
Stray light suppression in the Goddard IRAM 2-Millimeter Observer (GISMO)

Science.gov (United States)

Sharp, E. H.; Benford, D. J.; Fixsen, D. J.; Moseley, S. H.; Staguhn, J. G.; Wollack, E. J.

2012-09-01

The Goddard-IRAM Superconducting 2 Millimeter Observer (GISMO) is an 8x16 Transition Edge Sensor (TES) array of bolometers built as a pathfinder for TES detector development efforts at NASA Goddard Space Flight Center. GISMO has been used annually at the Institut de Radioastronomie Millimétrique (IRAM) 30 meter telescope since 2007 under engineering time and was opened in the spring of 2012 to the general astronomical community. The spring deployment provided an opportunity to modify elements of the room temperature optics before moving the instrument to its new permanent position in the telescope receiver cabin. This allowed for the possibility to extend the cryostat, introduce improved cold baffling and thus further optimize the stray light performance for final astronomical use of the instrument, which has been completed and validated. We will demonstrate and discuss several of the methods used to quantify and limit the influence of stray light in the GISMO camera.
The Design, Construction and Test of stray light suppression baffles for the CHAMP satellite

DEFF Research Database (Denmark)

Jørgensen, John Leif

1997-01-01

The Advanced Stellar Compass, to be delivered from IAU to the CHAMP project, requires some kind of stray-light suppressing shade to be mounted in front of the lens, in order to minimize the thermal impact and to maximize the performance envelope when subjected to non-stellar external light sources...

Effects of different levels of intraocular stray light on kinetic perimetry findings.

Directory of Open Access Journals (Sweden)

Kazunori Hirasawa

Full Text Available To evaluate the effect of different levels of intraocular stray light on kinetic perimetry findings.Twenty-five eyes of 25 healthy young participants were examined by automated kinetic perimetry (Octopus 900 using Goldmann stimuli III4e, I4e, I3e, I2e, and I1e. Each stimulus was presented with a velocity of 3°/s at 24 meridians with 15° intervals. Four levels of intraocular stray light were induced using non-white opacity filter (WOF filters and WOFs applied to the clear plastic eye covers of the participants. The visual acuity, pupil diameter, isopter area, and kinetic sensitivity of each meridian were analyzed for each WOF density.Visual acuity deteriorated with increasing WOF densities (p < 0.01. With a visual acuity of 0.1 LogMAR units, the isopter areas for III4e, I4e, I3e, I2e, and I1e decreased by -32.7 degree2 (-0.2%, -255.7 degree2 (-2.6%, -381.2 degree2 (-6.2%, -314.8 degree2 (-12.8%, and -59.2 degree2 (-15.2%, respectively; kinetic sensitivity for those stimuli decreased by -0.1 degree (-0.1%, -0.8 degree (-1.4%, -1.6 degree (-3.7%, -2.7 degree (-9.7%, and -1.7 degree (-16.2%, respectively. The pupil diameter with each WOF density was not significantly different.Kinetic perimetry measurements with a high-intensity stimulus (i.e., III4e were unaffected by intraocular stray light. In contrast, measurements with the I4e, I3e, I2e, and I1e stimuli, especially I2e and I1e, were affected. Changes in the shape of the isopter resulting from opacity must be monitored, especially in cases of smaller and lower-intensity stimuli.
Bidirectional reflectance distribution function /BRDF/ measurements of stray light suppression coatings for the Space Telescope /ST/

Science.gov (United States)

Griner, D. B.

1979-01-01

The paper considers the bidirectional reflectance distribution function (BRDF) of black coatings used on stray light suppression systems for the Space Telescope (ST). The ST stray light suppression requirement is to reduce earth, moon, and sun light in the focal plane to a level equivalent to one 23 Mv star per square arcsecond, an attenuation of 14 orders of magnitude. It is impractical to verify the performance of a proposed baffle system design by full scale tests because of the large size of the ST, so that a computer analysis is used to select the design. Accurate computer analysis requires a knowledge of the diffuse scatter at all angles from the surface of the coatings, for all angles of incident light. During the early phases of the ST program a BRDF scanner was built at the Marshall Space Flight Center to study the scatter from black materials; the measurement system is described and the results of measurements on samples proposed for use on the ST are presented.
Effects of stray lights on Faraday rotation measurement for polarimeter-interferometer system on EAST.

Science.gov (United States)

Zou, Z Y; Liu, H Q; Ding, W X; Chen, J; Brower, D L; Lian, H; Wang, S X; Li, W M; Yao, Y; Zeng, L; Jie, Y X

2018-01-01

A double-pass radially view 11 chords polarimeter-interferometer system has been operated on the experimental advanced superconducting tokamak and provides important current profile information for plasma control. Stray light originating from spurious reflections along the optical path (unwanted reflections from various optical components/mounts and transmissive optical elements such as windows, waveplates, and lens as well as the detectors) and also direct feedback from the retro-reflector used to realize the double-pass configuration can both contribute to contamination of the Faraday rotation measurement accuracy. Modulation of the Faraday rotation signal due to the interference from multiple reflections is observable when the interferometer phase (plasma density) varies with time. Direct reflection from the detector itself can be suppressed by employing an optical isolator consisting of a λ/4-waveplate and polarizer positioned in front of the mixer. A Faraday angle oscillation during the density ramping up (or down) can be reduced from 5°-10° to 1°-2° by eliminating reflections from the detector. Residual modulation arising from misalignment and stray light from other sources must be minimized to achieve accurate measurements of Faraday rotation.
STRAY - An interactive program for the computation of stray radiation in infrared telescopes

Science.gov (United States)

St. Clair Dinger, Ann

1987-01-01

The STRAY program to model the amount of stray radiation reaching the focal plane of a well-baffled telescope is described. The STRAY telescope model is addressed, including the aperture shade, barrel baffle, optics, mirror sectioning and chopping, and off-axis points in focal plane. The possible illumination paths are shown, and calculation options using STRAY are discussed. The stored data and computational aspects of STRAY are addressed. STRAY is compared to the MINI-APART model, and applications of STRAY are described.
Stray radiation and the Infrared Astronomical Satellite /IRAS/ telescope

Science.gov (United States)

Noll, R. J.; Harned, R.; Breault, R. P.; Malugin, R.

1981-01-01

Stray light control is a major consideration in the design of infrared cryogenically cooled telescopes such as the Infrared Astronomical Satellite (IRAS). The basic design of the baffle system, and the placement, shape, and coating of the secondary support struts for the telescope subsystem are described. The intent of this paper is to highlight the stray light problems encountered while designing the system, and to illustrate how computer analysis can be a useful design aid. Scattering measurements of the primary mirror, and a full system level scatter measurement are presented. Comparisons of predicted performance with the measured results are also presented.
Stray voltage mitigation

Energy Technology Data Exchange (ETDEWEB)

Jamali, B.; Piercy, R.; Dick, P. [Kinetrics Inc., Toronto, ON (Canada). Transmission and Distribution Technologies

2008-04-09

This report discussed issues related to farm stray voltage and evaluated mitigation strategies and costs for limiting voltage to farms. A 3-phase, 3-wire system with no neutral ground was used throughout North America before the 1930s. Transformers were connected phase to phase without any electrical connection between the primary and secondary sides of the transformers. Distribution voltage levels were then increased and multi-grounded neutral wires were added. The earth now forms a parallel return path for the neutral current that allows part of the neutral current to flow continuously through the earth. The arrangement is responsible for causing stray voltage. Stray voltage causes uneven milk production, increased incidences of mastitis, and can create a reluctance to drink water amongst cows when stray voltages are present. Off-farm sources of stray voltage include phase unbalances, undersized neutral wire, and high resistance splices on the neutral wire. Mitigation strategies for reducing stray voltage include phase balancing; conversion from single to 3-phase; increasing distribution voltage levels, and changing pole configurations. 22 refs., 5 tabs., 13 figs.
An assessment of the stray light in 25 years of Dobson total ozone data at Athens, Greece

Science.gov (United States)

Christodoulakis, J.; Varotsos, C.; Cracknell, A. P.; Tzanis, C.; Neofytos, A.

2015-07-01

In this study, we investigated the susceptibility of the Dobson spectrophotometer No. 118 to stray light interference. In this regard, a series of total ozone content measurements were carried out in Athens, Greece for air-mass values (μ) extending up to μ = 5. The monochromatic-heterochromatic stray light derived by Basher's model was used in order to evaluate the specific instrumental parameters which determine if this instrument suffers from this problem or not. The results obtained indicate that the measurements made by the Dobson instrument of the Athens station for air mass values up to 2.5, underestimates the total ozone content by 3.5 DU in average, or about 1 % of the station's mean total ozone content (TOC). The comparison of the values of the same parameters measured 15 years ago with the present ones indicates the good maintenance of the Dobson spectrophotometer No. 118. This fact is of crucial importance because the variability of the daily total ozone observations collected by the Athens Dobson Station since 1989 has proved to be representative to the variability of the mean total ozone observed over the whole mid-latitude zone of the Northern Hemisphere. This stresses the point that the Athens total ozone station, being the unique Dobson station in south-eastern Europe, may be assumed as a ground truth station for the reliable conversion of the satellite radiance observations to total ozone measurements.
Aerial firing and stray bullet injuries: a rising tide.

Science.gov (United States)

Ali, Syed Asad; Tahir, Syed Mohammad; Makhdoom, Asadullah; Shaikh, Abdul Razaque; Siddique, Akmal Jamal

2015-04-01

Aerial firing is shooting, using fire arm, into the air usually during a celebration. This observational study aimed to quantify magnitude and impact of stray bullet injuries by aerial firing at surgical emergencies of the Liaquat University Hospital (a university hospital), Hyderabad, Sindh, Pakistan from January 2009 to December 2010 (2 years). During the study period, 144 firearm injuries due to stray bullet reported to the A and E departments of the university hospital. All patients referred to surgical unit providing emergency cover on that day irrespective of the severity of the injury for medico-legal reasons. For this study, the cases were divided into those having trivial injury and do not require any active surgical intervention and those having serious injury mandating surgical intervention. One hundred and two cases of stray bullet injury sustained trivial injury and followed as outpatients after an overnight period of indoor hospitalization; however, 42 patients with stray bullet injuries requiring surgical intervention were hospitalized. The most common events leading to aerial firing and stray bullet injuries were marriage ceremonies, followed by a political rallies and New Year celebrations. Stray bullet injury also reported after aerial firing on cricket/hockey team victories, Pakistan Independence Day (14th August), cultural day in Sindh and Basant (Kite) festival in Punjab. The most frequent sites with serious stray bullet injury were chest (15), head and neck (10), abdomen (9) and limbs (8), respectively. Surgical interventions performed included chest intubation, exploration of wound tract to retrieve bullet if lodged superficially and was palpable, laparotomy to managed intra-abdominal injury, reduction of fracture site followed by reconstruction, flap reconstruction and graft for nonhealing wound. The mean duration of hospital stay was 19 days. No mortality was observed in this series of patients. We conclude that the prevalence of aerial
Image processing methods for noise reduction in the TJ-II Thomson Scattering diagnostic

Energy Technology Data Exchange (ETDEWEB)

Dormido-Canto, S., E-mail: sebas@dia.uned.es [Departamento de Informatica y Automatica, UNED, Madrid 28040 (Spain); Farias, G. [Pontificia Universidad Catolica de Valparaiso, Valparaiso (Chile); Vega, J.; Pastor, I. [Asociacion EURATOM/CIEMAT para Fusion, Madrid 28040 (Spain)

2012-12-15

Highlights: Black-Right-Pointing-Pointer We describe an approach in order to reduce or mitigate the stray-light on the images and show the exceptional results. Black-Right-Pointing-Pointer We analyze the parameters to take account in the proposed process. Black-Right-Pointing-Pointer We report a simplified exampled in order to explain the proposed process. - Abstract: The Thomsom Scattering diagnostic of the TJ-II stellarator provides temperature and density profiles. The CCD camera acquires images corrupted with noise that, in some cases, can produce unreliable profiles. The main source of noise is the so-called stray-light. In this paper we describe an approach that allows mitigation of the effects that stray-light has on the images: extraction regions with connected-components. In addition, the robustness and effectiveness of the noise reduction technique is validated in two ways: (1) supervised classification and (2) comparison of electron temperature profiles.
Low-Energy Microfocus X-Ray Source for Enhanced Testing Capability in the Stray Light Facility

Science.gov (United States)

Gaskin, Jessica; O'Dell, Stephen; Kolodziejczak, Jeff

2015-01-01

Research toward high-resolution, soft x-ray optics (mirrors and gratings) necessary for the next generation large x-ray observatories requires x-ray testing using a low-energy x-ray source with fine angular size (energy microfocus (approximately 0.1 mm spot) x-ray source from TruFocus Corporation that mates directly to the Stray Light Facility (SLF). MSFC X-ray Astronomy team members are internationally recognized for their expertise in the development, fabrication, and testing of grazing-incidence optics for x-ray telescopes. One of the key MSFC facilities for testing novel x-ray instrumentation is the SLF. This facility is an approximately 100-m-long beam line equipped with multiple x-ray sources and detectors. This new source adds to the already robust compliment of instrumentation, allowing MSFC to support additional internal and community x-ray testing needs.
Identification of Zoonotic Parasites isolated from Stray Dogs in Bojnurd County Located in North-East of Iran

Directory of Open Access Journals (Sweden)

Kourosh Arzamani

2016-10-01

Full Text Available Dog can represent as an important source of zoonotic disease and important health problem for human. They can carry dangerous parasitic diseases such as hydatidosis, toxocariasis and Coenurus cerebralis to humans and animals. This study was performed in order to determine the prevalence and intensity of zoonotic parasites among stray dogs from Bojnurd, the capital city of North Khorasan province in North West of Iran. During a program performing by Bojnurd municipal on the slow killing of stray dogs, 32 dogs from Jun 2013 till March 2015 were selected. At necropsy their alimentary canals were removed and to identify the species of helminthes, the nematodes were cleared in lactophenol and cestodes were stained using carmine acid. Intestinal protozoan parasites were detected with parasitological methods. 28 (87.5% of 32 stray dogs infected at least with one helminth. Seven species of cestodes were isolated from examined dogs and three species of nematode were detected. Giardia sp. and Cryptosporidium sp. detected from fecal samples. This is the first study of the prevalence of intestinal zoonotic parasites in dogs in this area. It seems control of bearing stray dogs can help human health and reduction economic losses caused by stray dog’s zoonotic parasites.
Detection of Hepatozoon canis in stray dogs and cats in Bangkok, Thailand.

Science.gov (United States)

Jittapalapong, Sathaporn; Rungphisutthipongse, Opart; Maruyama, Soichi; Schaefer, John J; Stich, Roger W

2006-10-01

A rapidly increasing stray animal population in Bangkok has caused concern regarding transmission of vector-borne and zoonotic diseases. The purpose of this study was to determine if stray animals in Bangkok are a potential reservoir of Hepatozoon, a genus of tick-borne parasites that has received little attention in Thailand. Blood samples were collected from stray companion animals near monasteries in 42 Bangkok metropolitan districts. Both dogs and cats were sampled from 26 districts, dogs alone from 4 districts and cats alone from 12 districts. Samples were collected from a total of 308 dogs and 300 cats. Light microscopy and an 18 S rRNA gene-based PCR assay were used to test these samples for evidence of Hepatozoon infection. Gamonts were observed in blood smears for 2.6% of dogs and 0.7% of cats by microscopy. The PCR assay detected Hepatozoon in buffy coats from 11.4% of dogs and 32.3% of cats tested. The prevalence of infection was the same between male and female dogs or cats, and PCR-positive dogs and cats were found in 36.6% and 36.8% of the districts surveyed, respectively. There was an association between the percentages of PCR-positive dogs and cats in districts where both host species were sampled. Sequences of representative amplicons were closest to those reported for H. canis. These results represent the first molecular confirmation that H. canis is indigenous to Thailand. The unexpectedly high prevalence of Hepatozoon among stray cats indicates that their role in the epizootiology of hepatozoonosis should be investigated.
STRAY DOG DETECTION IN WIRED CAMERA NETWORK

Directory of Open Access Journals (Sweden)

C. Prashanth

2013-08-01

Full Text Available Existing surveillance systems impose high level of security on humans but lacks attention on animals. Stray dogs could be used as an alternative to humans to carry explosive material. It is therefore imperative to ensure the detection of stray dogs for necessary corrective action. In this paper, a novel composite approach to detect the presence of stray dogs is proposed. The captured frame from the surveillance camera is initially pre-processed using Gaussian filter to remove noise. The foreground object of interest is extracted utilizing ViBe algorithm. Histogram of Oriented Gradients (HOG algorithm is used as the shape descriptor which derives the shape and size information of the extracted foreground object. Finally, stray dogs are classified from humans using a polynomial Support Vector Machine (SVM of order 3. The proposed composite approach is simulated in MATLAB and OpenCV. Further it is validated with real time video feeds taken from an existing surveillance system. From the results obtained, it is found that a classification accuracy of about 96% is achieved. This encourages the utilization of the proposed composite algorithm in real time surveillance systems.
Prevalence of external ear disorders in Belgian stray cats.

Science.gov (United States)

Bollez, Anouck; de Rooster, Hilde; Furcas, Alessandra; Vandenabeele, Sophie

2018-02-01

Objectives Feline otitis externa is a multifactorial dermatological disorder about which very little is known. The objective of this study was to map the prevalence of external ear canal disorders and the pathogens causing otitis externa in stray cats roaming around the region of Ghent, Belgium. Methods One hundred and thirty stray cats were randomly selected during a local trap-neuter-return programme. All cats were European Shorthairs. This study included clinical, otoscopic and cytological evaluation of both external ears of each cat. Prospective data used as parameters in this study included the sex, age and body condition score of each cat, as well as the presence of nasal and/or ocular discharge, and the results of feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV) Snap tests. Results Remarkably, very few (sub)clinical problems of the external ear canal were found in the stray cat population. Malassezia species was by far the most common organism found in the external ear canals of the 130 stray cats. A total of 96/130 (74%) cats were found to have Malassezia species organisms present in one or both ears based on the cytological examination. No correlation was found between the parameters of sex, age, body condition score, the presence of nasal and/or ocular discharge and FIV and FeLV status, and the presence of parasites, bacteria or yeasts. Conclusions and relevance This study provides more information about the normal state of the external ear canal of stray cats. The ears of most stray cats are relatively healthy. The presence of Malassezia species organisms in the external ear canal is not rare among stray cats.
Monitoring dc stray current corrosion at sheet pile structures

NARCIS (Netherlands)

Peelen, W.H.A.; Neeft, E.A.C.; Leegwater, G.; Kanten-Roos, W. van; Courage, W.M.G.

2012-01-01

Steel is discarded by railway owners as a material for underground structures near railway lines, due to uncertainty over increased corrosion by DC stray currents stemming from the traction power system. This paper presents a large scale field test in which stray currents interference of a sheet
The Disturbing Effect of the Stray Magnetic Fields on Magnetoimpedance Sensors

Directory of Open Access Journals (Sweden)

Tao Wang

2016-10-01

Full Text Available The disturbing effect of the stray magnetic fields of Fe-based amorphous ribbons on the giant magnetoimpedance (GMI sensor has been investigated systematically in this paper. Two simple methods were used for examining the disturbing effect of the stray magnetic fields of ribbons on the GMI sensor. In order to study the influence of the stray magnetic fields on the GMI effect, the square-shaped amorphous ribbons were tested in front, at the back, on the left and on the top of a meander-line GMI sensor made up of soft ferromagnetic films, respectively. Experimental results show that the presence of ribbons in front or at the back of GMI sensor shifts the GMI curve to a lower external magnetic field. On the contrary, the presence of ribbons on the left or on the top of the GMI sensor shifts the GMI curve to a higher external magnetic field, which is related to the coupling effect of the external magnetic field and the stray magnetic fields. The influence of the area and angle of ribbons on GMI was also studied in this work. The GMI sensor exhibits high linearity for detection of the stray magnetic fields, which has made it feasible to construct a sensitive magnetometer for detecting the typical stray magnetic fields of general soft ferromagnetic materials.
The quality of stray radiation in the ovarian region in diagnostic X-ray examinations

International Nuclear Information System (INIS)

Ewen, K.; Fiebach, B.J.O.; Fischer, P.G.; Loehr, E.

1976-01-01

Dose measurements (LiF-TLD) and recordings of stray radiation spectra (Ge(Li)-Detectors) in a phantom show that shielding of the ovaries against stray radiation is advisable even though the effectivity of this measure decreases at higher tube voltages. The exposure of the ovaries to stray radiation increases with increasing tube voltage; the radiation quality of the stray radiation is, for the most part, independent of the filter value. (orig./AK) [de
Reduction of ballistic spin scattering in a spin-FET using stray electric fields

International Nuclear Information System (INIS)

Nemnes, G A; Manolescu, A; Gudmundsson, V

2012-01-01

The quasi-bound states which appear as a consequence of the Rashba spin-orbit (SO) coupling, introduce a strongly irregular behavior of the spin-FET conductance at large Rashba parameter. Moreover, the presence of the bulk inversion asymmetry, i.e. the Dresselhaus SO coupling, may compromise the spin-valve effect even at small values of the Rashba parameter. However, by introducing stray electric fields in addition to the SO couplings, we show that the effect of the SO induced quasi-bound states can be tuned. The oscillations of the spin-resolved conductance become smoother and the control of the spin-FET characteristics becomes possible. For the calculations we employ a multi-channel scattering formalism, based on the R-matrix method extended to spin transport, in the presence of Rashba and Dresselhaus SO couplings.
Stray energy transfer during endoscopy.

Science.gov (United States)

Jones, Edward L; Madani, Amin; Overbey, Douglas M; Kiourti, Asimina; Bojja-Venkatakrishnan, Satheesh; Mikami, Dean J; Hazey, Jeffrey W; Arcomano, Todd R; Robinson, Thomas N

2017-10-01

Endoscopy is the standard tool for the evaluation and treatment of gastrointestinal disorders. While the risk of complication is low, the use of energy devices can increase complications by 100-fold. The mechanism of increased injury and presence of stray energy is unknown. The purpose of the study was to determine if stray energy transfer occurs during endoscopy and if so, to define strategies to minimize the risk of energy complications. A gastroscope was introduced into the stomach of an anesthetized pig. A monopolar generator delivered energy for 5 s to a snare without contacting tissue or the endoscope itself. The endoscope tip orientation, energy device type, power level, energy mode, and generator type were varied to mimic in vivo use. The primary outcome (stray current) was quantified as the change in tissue temperature (°C) from baseline at the tissue closest to the tip of the endoscope. Data were reported as mean ± standard deviation. Using the 60 W coag mode while changing the orientation of the endoscope tip, tissue temperature increased by 12.1 ± 3.5 °C nearest the camera lens (p energy transfer (p = 0.04 and p = 0.002, respectively) as did utilizing the low-voltage cut mode (6.6 ± 0.5 °C, p energy transfer compared to a standard generator (1.5 ± 3.5 °C vs. 9.5 ± 0.8 °C, p energy is transferred within the endoscope during the activation of common energy devices. This could result in post-polypectomy syndrome, bleeding, or perforation outside of the endoscopist's view. Decreasing the power, utilizing low-voltage modes and/or an impedance-monitoring generator can decrease the risk of complication.
Some aspects of stray losses in large power transformers

International Nuclear Information System (INIS)

Valkovic, Zvonimir

2002-01-01

The paper presents some results of the investigation of stray losses in power transformers that are caused by high-current loops. The investigation was focused on: a) additional losses in tank cover around high-current bushings and the way of their reduction, b) extra leakage flux and additional losses due to high current delta-connections. The insertion of nonmagnetic gaps between the phase bushings reduces the extra cover losses more than three times. A nonmagnetic plate around the high-current bushings reduces these extra losses practically to zero. The extra losses due to the high-current delta-connections could be significant for the transformer loss level. These extra losses could be controlled (reduced) by the design layout of the delta-connections. (Author)

A method to measure internal stray radiation of cryogenic infrared imaging systems under various ambient temperatures

Science.gov (United States)

Tian, Qijie; Chang, Songtao; Li, Zhou; He, Fengyun; Qiao, Yanfeng

2017-03-01

The suppression level of internal stray radiation is a key criterion for infrared imaging systems, especially for high-precision cryogenic infrared imaging systems. To achieve accurate measurement for internal stray radiation of cryogenic infrared imaging systems under various ambient temperatures, a measurement method, which is based on radiometric calibration, is presented in this paper. First of all, the calibration formula is deduced considering the integration time, and the effect of ambient temperature on internal stray radiation is further analyzed in detail. Then, an approach is proposed to measure the internal stray radiation of cryogenic infrared imaging systems under various ambient temperatures. By calibrating the system under two ambient temperatures, the quantitative relation between the internal stray radiation and the ambient temperature can be acquired, and then the internal stray radiation of the cryogenic infrared imaging system under various ambient temperatures can be calculated. Finally, several experiments are performed in a chamber with controllable inside temperatures to evaluate the effectiveness of the proposed method. Experimental results indicate that the proposed method can be used to measure internal stray radiation with high accuracy at various ambient temperatures and integration times. The proposed method has some advantages, such as simple implementation and the capability of high-precision measurement. The measurement results can be used to guide the stray radiation suppression and to test whether the internal stray radiation suppression performance meets the requirement or not.
Stray capacitances in the watt balance operation: electrostatic forces

DEFF Research Database (Denmark)

Quagliotti, Danilo; Mana, G.

2014-01-01

In a watt balance, stray capacitances exist between the coil and the magnet. Since the electric current flowing in the coil creates a difference in electric potentials between the coil and magnet, their electrostatic interactions must be taken into account. This paper reports the results of a fin......In a watt balance, stray capacitances exist between the coil and the magnet. Since the electric current flowing in the coil creates a difference in electric potentials between the coil and magnet, their electrostatic interactions must be taken into account. This paper reports the results...
The impact of microwave stray radiation to in-vessel diagnostic components

Energy Technology Data Exchange (ETDEWEB)

Hirsch, M.; Laqua, H. P.; Hathiramani, D.; Baldzuhn, J.; Biedermann, C.; Cardella, A.; Erckmann, V.; König, R.; Köppen, M.; Zhang, D. [Max-Planck-Institut für Plasmaphysik, Teilinstitut Greifswald, EURATOM Association, D-17489 Greifswald (Germany); Oosterbeek, J.; Brand, H. von der; Parquay, S. [Technische Universiteit Eindhoven, department Technische Natuurkunde, working group for Plasma Physics and Radiation Technology, Den Doelch 2, 5612 AZ Eindhoven (Netherlands); Jimenez, R. [Centro de Investigationes Energeticas, Medioambientales y Technológicas, Association EURATOM/CIEMAT, Avenida Complutense 22, Madrid 28040 (Spain); Collaboration: W7-X Teasm

2014-08-21

Microwave stray radiation resulting from unabsorbed multiple reflected ECRH / ECCD beams may cause severe heating of microwave absorbing in-vessel components such as gaskets, bellows, windows, ceramics and cable insulations. In view of long-pulse operation of WENDELSTEIN-7X the MIcrowave STray RAdiation Launch facility, MISTRAL, allows to test in-vessel components in the environment of isotropic 140 GHz microwave radiation at power load of up to 50 kW/m{sup 2} over 30 min. The results show that both, sufficient microwave shielding measures and cooling of all components are mandatory. If shielding/cooling measures of in-vessel diagnostic components are not efficient enough, the level of stray radiation may be (locally) reduced by dedicated absorbing ceramic coatings on cooled structures.
Stray current monitoring at Nuremberg subway; Streustromueberwachung bei der U-Bahn Nuernberg

Energy Technology Data Exchange (ETDEWEB)

Altmann, M.; Halfmann, U.; Schneider, E. [Siemens AG, Erlangen (Germany). TS EL EN 2; Roesch, N. [VAG Verkehrs-AG Nuernberg, FA/SA - Starkstromanlagen, Nuernberg (Germany)

2004-05-01

Operating DC traction systems requires protective measures against the effects of stray currents. Damage by corrosion could occur both at railway and third party installations. The continuous effectiveness of protective measures needs to be monitored and recorded during revenue operation, and shall be capable to be demonstrated to supervising authorities. Measuring the rail-to-earth potential within the traction network under operational conditions, combined with centralized analysis, visualization, signaling and archiving is a straightforward and efficient method of stray current monitoring. For more than one year, the stray current monitoring system SITRAS SMS {sup registered} has been undergoing successful field application at the Nuremberg Subway. (orig.)
A degradation model for stray current induced corrosion in underground reinforced concrete structures

NARCIS (Netherlands)

Polder, R.B.; Peelen, W.H.A.

2003-01-01

This paper describes the effects of stray currents on durability and reinforcement corrosion of underground concrete structures. Cathodic protection of underground pipelines are stationary sources of stray current interference with concrete, and rail traction systems are non-stationary sources. The
Self-propagating solar light reduction of graphite oxide in water

Energy Technology Data Exchange (ETDEWEB)

Todorova, N.; Giannakopoulou, T.; Boukos, N.; Vermisoglou, E. [Institute of Nanoscience and Nanotechnology, NCSR “Demokritos”, 153 41 Attikis (Greece); Lekakou, C. [Division of Mechanical, Medical, and Aerospace Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford (United Kingdom); Trapalis, C., E-mail: c.trapalis@inn.demokritos.gr [Institute of Nanoscience and Nanotechnology, NCSR “Demokritos”, 153 41 Attikis (Greece)

2017-01-01

Highlights: • Graphite oxide was partially reduced by solar light irradiation in water media. • No addition of catalysts nor reductive agent were used for the reduction. • Specific capacitance increased stepwise with increase of irradiation time. • Self-propagating reduction of graphene oxide by solar light is suggested. - Abstract: Graphite Oxide (GtO) is commonly used as an intermediate material for preparation of graphene in the form of reduced graphene oxide (rGO). Being a semiconductor with tunable band gap rGO is often coupled with various photocatalysts to enhance their visible light activity. The behavior of such rGO-based composites could be affected after prolonged exposure to solar light. In the present work, the alteration of the GtO properties under solar light irradiation is investigated. Water dispersions of GtO manufactured by oxidation of natural graphite via Hummers method were irradiated into solar light simulator for different periods of time without addition of catalysts or reductive agent. The FT-IR analysis of the treated dispersions revealed gradual reduction of the GtO with the increase of the irradiation time. The XRD, FT-IR and XPS analyses of the obtained solid materials confirmed the transition of GtO to rGO under solar light irradiation. The reduction of the GtO was also manifested by the CV measurements that revealed stepwise increase of the specific capacitance connected with the restoration of the sp{sup 2} domains. Photothermal self-propagating reduction of graphene oxide in aqueous media under solar light irradiation is suggested as a possible mechanism. The self-photoreduction of GtO utilizing solar light provides a green, sustainable route towards preparation of reduced graphene oxide. However, the instability of the GtO and partially reduced GO under irradiation should be considered when choosing the field of its application.
Electrolytic corrosion of water pipeline system in the remote distance from stray currents—Case study

Directory of Open Access Journals (Sweden)

Krzysztof Zakowski

2016-06-01

Full Text Available Case study of corrosion failure of urban water supply system caused by the harmful effects of stray currents was presented. The failure occurred at a site distant from the sources of these currents namely the tramway and railway traction systems. Diagnosis revealed the stray currents flow to pipeline over a remote distance of 800/1000 m from the point of failure. At the point of failure stray currents flowed from the pipeline to the ground through external insulation defects, causing the process of electrolytic corrosion of the metal. Long distance between the affected section of the pipeline and the sources of stray currents excludes the typical protection against stray currents in the form of electrical polarized drainage. Corrosion protection at this point can be achieved by using the earthing electrodes made of magnesium, which will also provide cathodic current protection as galvanic anode.
A survey of gastrointestinal helminth of stray dogs in Zabol city, southeastern of Iran

Directory of Open Access Journals (Sweden)

Geraili, A.

2016-03-01

Full Text Available Canids are reservoir for some zoonoses helminthic disease. They are one of main public health problem. The aim of this study was to ascertain frequency of gastrointestinal helminthic infection of stray dogs in Zabol city, southeaster of Iran. In this descriptive study, 30 stray dogs were euthanized, intestine was removed by necropsy. Then, the intestines was opened by scalpel and their contents passed through mesh sieve. The helminth were collected. The nematodes were preserved in 70% ethanol with 5% glycerin and cestodes were preserved in 70% ethanol. The cestodes were stained by acetocarmine. The nematodes were cleared by lactophenol. The genus and species of helminth were identified by identification keys. Twenty two (73.3% of stray dogs had at least one intestinal helminthic infection. Recovered helminth from stray dogs include: Taenia hydatigena (53.3%, Taenia ovis (20%, Taenia multiceps (6.6%, Mesocestoides spp (10%, Toxocara canis (23.3%, Toxocara cati (3.3%. Data showed that the stray dogs in Zabol city harbor some important zoonoses helminth parasite like Toxocara.
Stray-electron accumulation and effects in HIF accelerators

International Nuclear Information System (INIS)

Cohen, R.H.; Friedman, A.; Furman, M.A.; Lund, S.M.; Molvik, A.W.; Stoltz, P.; Vay, J.-L.

2003-01-01

Stray electrons can be introduced in positive-charge accelerators for heavy ion fusion (or other applications) as a result of ionization of ambient gas or gas released from walls due to halo-ion impact, or as a result of secondary-electron emission. Electron accumulation is impacted by the ion beam potential, accelerating fields, multipole magnetic fields used for beam focus, and the pulse duration. We highlight the distinguishing features of heavy-ion accelerators as they relate to stray-electron issues, and present first results from a sequence of simulations to characterize the electron cloud that follows from realistic ion distributions. Also, we present ion simulations with prescribed random electron distributions, undertaken to begin to quantify the effects of electrons on ion beam quality
[Scattered light and glare sensitivity after wavefront-guided photorefractive keratectomy (WFG-PRK) and laser in situ keratomileusis (WFG-LASIK)].

Science.gov (United States)

Vignal, R; Tanzer, D; Brunstetter, T; Schallhorn, S

2008-05-01

To compare glare sensitivity measured by the intraocular scattered light between WFG-PRK and WFG-LASIK at 12 months follow-up and to assess its correlation to patients' complaints. Prospective and randomized study on 13 patients treated with WFG-LASIK, 13 patients with WFG-PRK and a control group of 35 patients. The intraocular stray light was measured by the Oculus C-Quant 12 months after surgery and before surgery for the control group. Photopic and mesopic contrast acuity and glare symptoms were reported pre- and postoperatively. Stray light values were normal in 79% of patients after WFG-LASIK and PRK and 86% in the control group, with mean values of 1.05 log, 1.03 log, and 0.99 log, respectively (p>0.05). All the patients with significant glare complaints had impaired stray light values versus 31.5% in the no-complaint group. Photopic and mesopic contrast acuity and glare symptoms were improved 1 year after surgery compared to preoperatively (no significant difference between groups). WFG-LASIK and PRK are safe and equivalent procedures regarding quality of vision. The measurement of stray light can be a discriminative test to assessing patients' glare complaints.
A Choice Experiment Analysis of the Management of the Stray Dog Population in the UK.

OpenAIRE

Siettou, Christina; Fraser, Iain; Fraser, Rob

2013-01-01

In this paper we present the results of a pilot study investigating the public’s view on the pet overpopulation problem. The Choice Experiment aims to understand the UK public’s awareness of the issue, its views and its willingness to participate and pay for a reduction in the rate of animals being “put to sleep”. Our preliminary results indicate that the public are willing to pay to keep healthy stray dogs alive for longer in Local Authority kennels beyond the current seven day statutory per...
Experimental observations of stray current effects on steel fibres embedded in mortar

DEFF Research Database (Denmark)

Solgaard, A.O.S.; Carsana, M.; Geiker, M.R.

2013-01-01

It is known that stray direct current can cause corrosive damage over time to bar reinforced concrete, but knowledge on the consequences to steel fibre reinforced concrete is limited. This paper presents analyses and corresponding results from an experimental program (parametric study) investigat......It is known that stray direct current can cause corrosive damage over time to bar reinforced concrete, but knowledge on the consequences to steel fibre reinforced concrete is limited. This paper presents analyses and corresponding results from an experimental program (parametric study......) investigating the conditions required for current to be picked up by embedded steel fibres or reinforcement (rebars). The experiments showed that there is a clear ‘length effect’ related to the susceptibility of stray current being picked up by embedded steel (fibres or rebars): the shorter the reinforcement...
Stray dog and cat laws and enforcement in Czech Republic and in Italy

Directory of Open Access Journals (Sweden)

Eva Voslářvá

2012-01-01

Full Text Available The growing numbers of stray dogs and cats have posed serious public-health, socioeconomic, political and animal-welfare problems in many EU countries. Stray animal population control is a complex issue and there are no easy solutions. Recognising the importance of the issue the European Commission has, since 2007, actively contributed to the elaboration of the first global welfare standards for the control of dog populations in the framework of the World Organisation for Animal Health (OIE. Problem-solving approaches vary in different countries as there is no common European Community legislation dealing with stray animal control. In this paper the authors describe the characteristics of the stray dog and cat problem in general and focus on existing European legislation. A comparative overview of policies and measures in place in the Czech Republic and in Italy is made to observe the differences between the two countries and understand the different needs in each, considering their historical and social differences (i.e. a post-communist eastern country vs a western country and founder member of what is now the European Union.
The reduction of retinal autofluorescence caused by light exposure.

Science.gov (United States)

Morgan, Jessica I W; Hunter, Jennifer J; Merigan, William H; Williams, David R

2009-12-01

A prior study showed that long exposure to 568-nm light at levels below the maximum permissible exposure safety limit produces retinal damage preceded by a transient reduction in the autofluorescence of retinal pigment epithelial (RPE) cells in vivo. The present study shows how the effects of exposure power and duration combine to produce this autofluorescence reduction and find the minimum exposure causing a detectable autofluorescence reduction. Macaque retinas were imaged using a fluorescence adaptive optics scanning laser ophthalmoscope to resolve individual RPE cells in vivo. The retina was exposed to 568-nm light over a square subtending 0.5 degrees with energies ranging from 1 to 788 J/cm(2), where power and duration were independently varied. In vivo exposures of 5 J/cm(2) and higher caused an immediate decrease in autofluorescence followed by either full autofluorescence recovery (exposures or= 247 J/cm(2)). No significant autofluorescence reduction was observed for exposures of 2 J/cm(2) and lower. Reciprocity of exposure power and duration held for the exposures tested, implying that the total energy delivered to the retina, rather than its distribution in time, determines the amount of autofluorescence reduction. That reciprocity held is consistent with a photochemical origin, which may or may not cause retinal degeneration. The implementation of safe methods for delivering light to the retina requires a better understanding of the mechanism causing autofluorescence reduction. Finally, RPE imaging was demonstrated using light levels that do not cause a detectable reduction in autofluorescence.
Searching for O-X-B mode-conversion window with monitoring of stray microwave radiation in LHD

International Nuclear Information System (INIS)

Igami, H.; Kubo, S.; Laqua, H. P.; Nagasaki, K.; Inagaki, S.; Notake, T.; Shimozuma, T.; Yoshimura, Y.; Mutoh, T.; LHD Experimental Group

2006-01-01

In the Large Helical Device, the stray microwave radiation is monitored by using so-called sniffer probes during electron cyclotron heating. In monitoring the stray radiation, we changed the microwave beam injection angle and search the O-X-B mode-conversion window to excite electron Bernstein waves (EBWs). When the microwave beam is injected toward the vicinity of the predicted O-X-B mode-conversion window, the electron temperature rises in the central part of overdense plasmas. In that case, the stray radiation level near the injection antenna becomes low. These results indicate that monitoring the stray radiation near the injection antenna is helpful in confirming the effectiveness of excitation of EBWs simply without precise analysis
FACT light collection - solid light concentrators in Cherenkov Astronomy

Energy Technology Data Exchange (ETDEWEB)

Braun, Isabel [ETH Zurich, Institute for Particle Physics, CH-8093 Zurich (Switzerland); Collaboration: FACT-Collaboration

2011-07-01

Pixelized cameras of Imaging Atmospheric Cherenkov Telescopes use hollow light guides with reflective surfaces based on the Winston cone design. These cones minimize insensitive spaces between the photo sensors and shield the camera from stray background light by limiting the angular acceptance to the primary reflector area. FACT (First G-APD Cherenkov Telescope) will be the first IACT with Geiger-mode avalanche photodiodes as light sensors. Solid light concentrators complementing these sensors will be used instead of hollow Winston cones. We will present simulations and measurements of our light collector design, which was optimized for the requirements of the FACT telescope and detector, and discuss the specific differences to more traditional solutions.
Seroepidemiological survey of helminthic parasites of stray dogs in Sari City, northern Iran.

Science.gov (United States)

Gholami, Ishirzad; Daryani, Ahmad; Sharif, Mehdi; Amouei, Afsaneh; Mobedi, Iraj

2011-01-15

The objective of this study was to determine the prevalence rate of helminthic parasites in stray dogs' population especially zoonotic infections and to identify potential risk factors in the different areas of Sari city in Caspian area, north of Iran. During the period from April to September 2007, 50 stray dogs were collected from urban areas of Sari city. Recovered parasites were fixed in alcohol and stained by carmine then observed by microscope. The taxonomic study was carried out by measuring different parts of the body of helminthes and statistical tests were performed using the Chi-square test. A total of 27 adult and 23 juvenile stray dogs were collected and the overall prevalence rate of infection was 90%. The three most common helminthes were Toxocara canis (60%), Ancylostoma caninum (46%) and Dipylidium caninum (36%). Other parasites were Uncinaria stenocephala (12%), Taenia hydatigena (6%), Spirocerca lupi (6%), Dirofilaria immitis (6%), Toxascaris leonina (2%), Rictularia sp. (2%), Taenia ovis (2%) and Taenia taeniformis (2%). Five species of zoonotic helminthes recovered were T. canis, A. caninum, U. stenocephala, D. caninum and D. immitis. Hookworm infections (58%) were more common significantly in the young stray dogs (p caninum, T. canis and U. stenocephala, there was significant difference between juvenile and adult dogs (p < 0.05). The results highlight the potential role of stray dogs for transmission of helminthic parasites particularly zoonotic parasites that are a significant risk to human health.
WIDESPREAD OF STRAY DOGS: METHODS FOR SOLVING THE PROBLEM IN CERTAIN REGIONS OF BOSNIA AND HERZEGOVINA

OpenAIRE

Muhamed Katica; Nedzad Gradascevic; Nejra Hadzimusic; Zarema Obradovic; Ramo Mujkanovic; Esad Mestric; Senad Coloman; Muhamed Dupovac

2017-01-01

Stray dogs are the ones not microchipped, which live across the streets and other public surfaces unattended, and so represent a serious public-health problem. Lack of human support for the stray dogs causes a range of problems - from territorial status to ensuring food. Such conditions force them to activate a self-preservation mechanism and return to natural behavioral patterns. Regarding the fact that several thousands of stray dogs were recorded in observed regions of Bosnia and Herze...
Monitoring millimeter wave stray radiation during ECRH operation at ASDEX Upgrade

Science.gov (United States)

Schubert, M.; Honecker, F.; Monaco, F.; Schmid-Lorch, D.; Schütz, H.; Stober, J.; Wagner, D.

2012-09-01

Due to imperfection of the single path absorption, ECRH at ASDEX Upgrade (AUG) is always accompanied by stray radiation in the vacuum vessel. New ECRH scenarios with O2 and X3 heating schemes extend the operational space, but they have also the potential to increase the level of stray radiation. There are hazards for invessel components. Damage on electric cables has already been encountered. It is therefore necessary to monitor and control the ECRH with respect to the stray radiation level. At AUG a system of Sniffer antennas equipped with microwave detection diodes is installed. The system is part of the ECRH interlock circuit. We notice, however, that during plasma operation the variations of the Sniffer antenna signal are very large. In laboratory measurements we see variations of up to 20 dB in the directional sensitivity and we conclude that an interference pattern is formed inside the copper sphere of the antenna. When ECRH is in plasma operation at AUG, the plasma is acting as a phase and mode mixer for the millimeter waves and thus the interference pattern inside the sphere changes with the characteristic time of the plasma dynamics. In order to overcome the difficulty of a calibrated measurement of the average stray radiation level, we installed bolometer and pyroelectric detectors, which intrinsically average over interference structures due to their large active area. The bolometer provides a robust calibration but with moderate temporal resolution. The pyroelectric detector provides high sensitivity and a good temporal resolution, but it raises issues of possible signal drifts in long pulses.
Monitoring millimeter wave stray radiation during ECRH operation at ASDEX Upgrade

Directory of Open Access Journals (Sweden)

Wagner D.

2012-09-01

Full Text Available Due to imperfection of the single path absorption, ECRH at ASDEX Upgrade (AUG is always accompanied by stray radiation in the vacuum vessel. New ECRH scenarios with O2 and X3 heating schemes extend the operational space, but they have also the potential to increase the level of stray radiation. There are hazards for invessel components. Damage on electric cables has already been encountered. It is therefore necessary to monitor and control the ECRH with respect to the stray radiation level. At AUG a system of Sniffer antennas equipped with microwave detection diodes is installed. The system is part of the ECRH interlock circuit. We notice, however, that during plasma operation the variations of the Sniffer antenna signal are very large. In laboratory measurements we see variations of up to 20 dB in the directional sensitivity and we conclude that an interference pattern is formed inside the copper sphere of the antenna. When ECRH is in plasma operation at AUG, the plasma is acting as a phase and mode mixer for the millimeter waves and thus the interference pattern inside the sphere changes with the characteristic time of the plasma dynamics. In order to overcome the difficulty of a calibrated measurement of the average stray radiation level, we installed bolometer and pyroelectric detectors, which intrinsically average over interference structures due to their large active area. The bolometer provides a robust calibration but with moderate temporal resolution. The pyroelectric detector provides high sensitivity and a good temporal resolution, but it raises issues of possible signal drifts in long pulses.

Simplified magnetic circuit for the calculation of the stray magnetic flux through the shell gaps

Energy Technology Data Exchange (ETDEWEB)

Collarin, P.; Piovan, R. [Associazioni EURATOM-ENEA-CNR-Univ. di Padova (Italy). Gruppo di Padova per Ricerche sulla Fusione

1995-12-31

Significant toroidal magnetic field perturbations, stray flux at the shell gaps and current mismatching in the coils of the toroidal field winding are measured during the start-up and the flat-top phases of RFX. These phenomena are consistent with large and wall locked MHD modes: at first some m = 1 modes evolve separately one after the other, afterwards they concur to a wide and localized plasma perturbation that persists during the flat-top. These perturbations are heavily influenced by the stray magnetic flux through the shell gaps. Hence a magnetic circuit that mainly considers the magnetic reluctance of the conducting shell gaps has been developed in order to estimate this stray flux and, therefore, to evaluate the stabilizing capability of the shell. The observation of the MHD modes, the description of the equivalent magnetic network, the estimation of the stray flux and the comparison with the experimental measurements are reported in the paper.
Simplified magnetic circuit for the calculation of the stray magnetic flux through the shell gaps

International Nuclear Information System (INIS)

Collarin, P.; Piovan, R.

1995-01-01

Significant toroidal magnetic field perturbations, stray flux at the shell gaps and current mismatching in the coils of the toroidal field winding are measured during the start-up and the flat-top phases of RFX. These phenomena are consistent with large and wall locked MHD modes: at first some m = 1 modes evolve separately one after the other, afterwards they concur to a wide and localized plasma perturbation that persists during the flat-top. These perturbations are heavily influenced by the stray magnetic flux through the shell gaps. Hence a magnetic circuit that mainly considers the magnetic reluctance of the conducting shell gaps has been developed in order to estimate this stray flux and, therefore, to evaluate the stabilizing capability of the shell. The observation of the MHD modes, the description of the equivalent magnetic network, the estimation of the stray flux and the comparison with the experimental measurements are reported in the paper
Seroprevalence of Ehrlichia canis infection in stray dogs from Serbia

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Nataša Bogićević

2017-03-01

Full Text Available Canine Monocytic Ehrlichiosis is a zoonotic bacterial disease with worldwide distribution. With regards to the population of stray dogs, the disease is facilitated due to their lifestyle and the lack of anti-parasitic protection. The aim of this study was to provide serological data on the presence of a specific Ehrlichia canis IgG antibodies in stray dogs, originating from 7 municipalities in Serbia. During the period from April 2013 to June 2014, 217 canine sera were submitted to the laboratory of the Department of Infectious Diseases of Animals and Bees, Faculty of Veterinary Medicine in Belgrade. An immunofluorescent antibody test (IFAT was performed to detect antibodies to Ehrlichia canis (cut off, 1:50. Seropositive dogs were found in 5 out of 7 counties with a seroprevalence varying from 3.57% to 20% and an overall seroprevalence of 11.06% (24/217. There was no statistically significant difference between the prevalence of infection and the host age or gender. Results showed that stray dogs contribute to maintaining and spreading of Ehrlichia canis in Serbia. Due to the close relationship between people and dogs, it is of great importance to constantly monitor and improve prevention of this disease.
PCR-Based Molecular Characterization of Toxocara spp. Using Feces of Stray Cats: A Study from Southwest Iran

OpenAIRE

Khademvatan, Shahram; Rahim, Fakher; Tavalla, Mahdi; Abdizadeh, Rahman; Hashemitabar, Mahmoud

2013-01-01

Feces of stray cat are potential sources of gastrointestinal parasites and play a crucial role in spreading and transmitting parasite eggs, larvae, and oocysts through contamination of soil, food, or water. In this study, we investigated the prevalence of Toxocara spp. infection in stray cats in Ahvaz city, southwest Iran. Eggs of Toxocara spp. in feces of stray cats were detected by the sucrose flotation method, and identification was conducted by polymerase chain reaction (PCR) and DNA sequ...
Convergence of highly parallel stray field calculation using the fast multipole method on irregular meshes

Science.gov (United States)

Palmesi, P.; Abert, C.; Bruckner, F.; Suess, D.

2018-05-01

Fast stray field calculation is commonly considered of great importance for micromagnetic simulations, since it is the most time consuming part of the simulation. The Fast Multipole Method (FMM) has displayed linear O(N) parallelization behavior on many cores. This article investigates the error of a recent FMM approach approximating sources using linear—instead of constant—finite elements in the singular integral for calculating the stray field and the corresponding potential. After measuring performance in an earlier manuscript, this manuscript investigates the convergence of the relative L2 error for several FMM simulation parameters. Various scenarios either calculating the stray field directly or via potential are discussed.
A study on protozoan infections (Giardia, Entamoeba, Isoapora and Cryptosporidium in stray dogs in Ilam province

Directory of Open Access Journals (Sweden)

S Kakekhani

2011-11-01

Full Text Available Giardia, Entamoeba, Isospora and Cryptosporidium are important protozoan parastites that caused diarrhea in human and animals. In the present study, fecal samples were collected fresh, directly from the rectum of 112 stray dogs in Ilam province. Giardia and Entamoeba were concentrated by using the formalin ether sedimentation method followed by the trichrome and iodine staining technique andCryptosporidium oocysts were concentrated by using the formalin ether sedimentation method followed by the modified Ziehl-Neelsen staining technique. Of 112 stray dogs, protozoan infections were detected from feces of 46 dogs (41.07% that Giardia infection was detected from feces of 21 dogs (18.75%, Isospora 17 (15.17%, Cryptosporidium 8 (7.14% and synchronization infection to 2 protozoan in 9 dogs (8.03% and to 3 protozoan in 3 (2.67%. In the present study not observed to Entamoeba. No statistically significant differences in prevalence of protozoan parasites occurred between female (34.21 % and male (55.5 % stray dogs (p>0/05. But statistically significant differences in prevalence occurred between 1≥0 and 0 ≥1 stray dogs (p>0/05. So that stray dogs of Ilam province can cause infection of human water and food sources.
Internal stray radiation measurement for cryogenic infrared imaging systems using a spherical mirror.

Science.gov (United States)

Tian, Qijie; Chang, Songtao; He, Fengyun; Li, Zhou; Qiao, Yanfeng

2017-06-10

Internal stray radiation is a key factor that influences infrared imaging systems, and its suppression level is an important criterion to evaluate system performance, especially for cryogenic infrared imaging systems, which are highly sensitive to thermal sources. In order to achieve accurate measurement for internal stray radiation, an approach is proposed, which is based on radiometric calibration using a spherical mirror. First of all, the theory of spherical mirror design is introduced. Then, the calibration formula considering the integration time is presented. Following this, the details regarding the measurement method are presented. By placing a spherical mirror in front of the infrared detector, the influence of internal factors of the detector on system output can be obtained. According to the calibration results of the infrared imaging system, the output caused by internal stray radiation can be acquired. Finally, several experiments are performed in a chamber with controllable inside temperatures to validate the theory proposed in this paper. Experimental results show that the measurement results are in good accordance with the theoretical analysis, and demonstrate that the proposed theories are valid and can be employed in practical applications. The proposed method can achieve accurate measurement for internal stray radiation at arbitrary integration time and ambient temperatures. The measurement result can be used to evaluate whether the suppression level meets the system requirement.
Chronic light reduction reduces overall resilience to additional shading stress in the seagrass

NARCIS (Netherlands)

Yaakub, S.M.; Chen, E.; Bouma, T.; Erftemeijer, P.L.A.; Todd, P.A.

2014-01-01

Seagrasses have substantial capacity to survive long periods of light reduction, but how acclimation to chronic low light environments may influence their ability to cope with additional stress is poorly understood. This study examines the effect of temporal light reduction by adding two levels of
It’s a Dog’s Life: International Tourists’ Perceptions of the Stray Dog Population of Bhutan.

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Paul C Strickland

2015-12-01

Full Text Available This study investigates the international tourists’ perception of the stray dog population of Bhutan as little or no mention of the increasing stray dog population and their impact on tourism has been documented. After personally visiting the Kingdom on many occasions, it is evident that the stray dog population is increasing in dog numbers in major cities. The problems arising are negative comments by tourists relating to the stray dog population that are starting to appear in social media that may impact the visitor experience and the perception of Bhutan’s tourism industry. Veterinary science is aware of both increasing dog populations and the control of diseases such as Rabies however the author can find no evidence regarding challenges for the tourism industry. The problem is aided by no local veterinary clinics, no laws regarding dog governance, little funding for sterilization programs and being predominately a Buddhist country that cannot ‘cull’ animals. Using qualitative analysis from international tourist focus groups who were visiting Bhutan, this study highlights the perceptions of tourists regarding the stray dog population and how it may impact on visitor expectations. The paper suggests options that local government, Bhutanese nationals and visitors can do to assist the issue based on visitor feedback. Future research may include comparisons with other cities or countries to examine if it is a global issue or unique to Bhutan.
Bartonella and Toxoplasma Infections in Stray Cats from Iraq

Science.gov (United States)

Switzer, Alexandra D.; McMillan-Cole, Audrey C.; Kasten, Rickie W.; Stuckey, Matthew J.; Kass, Philip H.; Chomel, Bruno B.

2013-01-01

Because of overpopulation, stray/feral cats were captured on military bases in Iraq as part of the US Army Zoonotic Disease Surveillance Program. Blood samples were collected from 207 cats, mainly in Baghdad but also in North and West Iraq, to determine the prevalence of Bartonella and Toxoplasma infections. Nine (4.3%) cats, all from Baghdad, were bacteremic with B. henselae type I. Seroprevalence was 30.4% for T. gondii, 15% for B. henselae, and 12.6% for B. clarridgeiae. Differences in Bartonella prevalence by location were statistically significant, because most of the seropositive cats were from Baghdad. There was no association between T. gondii seropositivity and either of the two Bartonella species surveyed. This report is the first report on the prevalence of Bartonella and T. gondii among stray cats in Iraq, which allows for better evaluation of the zoonotic risk potential to the Iraqi people and deployed military personnel by feral cat colonies. PMID:24062480
Problems Associated with the Microchip Data of Stray Dogs and Cats Entering RSPCA Queensland Shelters

Science.gov (United States)

Lancaster, Emily; Rand, Jacquie; Collecott, Sheila; Paterson, Mandy

2015-01-01

Simple Summary Microchip identification has become an important tool to reunite stray dogs and cats with their owners, and is now compulsory in most states of Australia. Improvement of the microchipping system in Australia is limited by a lack of published Australian data documenting the problems experienced by shelter staff when using microchip data to contact the owner of a stray animal. In this study we determine the character and frequency of inaccurate microchip data to identify weaknesses in the current microchipping system. This information could be used to develop strategies that increase the accuracy of microchip data that will increase the reclaiming of stray animals. Abstract A lack of published information documenting problems with the microchip data for the reclaiming of stray animals entering Australian shelters limits improvement of the current microchipping system. A retrospective study analysing admission data for stray, adult dogs (n = 7258) and cats (n = 6950) entering the Royal Society for the Prevention of Cruelty to Animals (RSPCA) Queensland between January 2012 and December 2013 was undertaken to determine the character and frequency of microchip data problems and their impact on outcome for the animal. Only 28% of dogs and 9% of cats were microchipped, and a substantial proportion (37%) had problems with their data, including being registered to a previous owner or organisation (47%), all phone numbers incorrect/disconnected (29%), and the microchip not registered (14%). A higher proportion of owners could be contacted when the microchip had no problems, compared to those with problems (dogs, 93% vs. 70%; cats, 75% vs. 41%). The proportion of animals reclaimed declined significantly between microchipped animals with no data problems, microchipped animals with data problems and non-microchipped animals—87%, 69%, and 37%, respectively, for dogs and 61%, 33%, and 5%, respectively, for cats. Strategies are needed to increase the accuracy of
Feline immunodeficiency virus testing in stray, feral, and client-owned cats of Ottawa

OpenAIRE

Little, Susan E.

2005-01-01

Feline immunodeficiency virus (FIV) seroprevalence is evaluated in 3 groups of cats. Seventy-four unowned urban strays were tested, as well as 20 cats from a small feral cat colony, and 152 client-owned cats. Of the 246 cats tested, 161 (65%) were male and 85 (35%) were female. Seroprevalence for FIV was 23% in the urban strays, 5% in the feral cat colony, and 5.9% in the client-owned cats. Ten cats (4%) were also positive for Feline leukemia virus (FeLV) antigen, including 2 cats coinfected ...
Stray current vs anodic polarization in reinforced mortar: a comparative study on steel corrosion behaviour in both regimes

NARCIS (Netherlands)

Chen, Zhipei; Koleva, D.A.; van Breugel, K.

2015-01-01

Stray current arising from direct current electrified traction systems and then circulat-ing in reinforced concrete structures may initiate corrosion or even accelerate existing corrosion processes on embedded reinforcement. Therefore, stray-current induced corrosion of nearby reinforced concrete
Residual stress characterization of steel TIG welds by neutron diffraction and by residual magnetic stray field mappings

Energy Technology Data Exchange (ETDEWEB)

Stegemann, Robert, E-mail: Robert.Stegemann@bam.de [Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12200 Berlin (Germany); Cabeza, Sandra; Lyamkin, Viktor; Bruno, Giovanni; Pittner, Andreas [Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12200 Berlin (Germany); Wimpory, Robert; Boin, Mirko [HZB Helmholtz-Zentrum Berlin, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Kreutzbruck, Marc [Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12200 Berlin (Germany); IKT, University of Stuttgart, Pfaffenwaldring 32, 70569 Stuttgart (Germany)

2017-03-15

The residual stress distribution of tungsten inert gas welded S235JRC+C plates was determined by means of neutron diffraction (ND). Large longitudinal residual stresses with maxima around 600 MPa were found. With these results as reference, the evaluation of residual stress with high spatial resolution GMR (giant magneto resistance) sensors was discussed. The experiments performed indicate a correlation between changes in residual stresses (ND) and the normal component of local residual magnetic stray fields (GMR). Spatial variations in the magnetic field strength perpendicular to the welds are in the order of the magnetic field of the earth. - Highlights: • Comparison of magnetic microstructure with neutron diffraction stress analysis. • High spatial resolution magnetic stray field images of hypereutectoid TIG welds. • Spatial variations of the stray fields are below the magnetic field of the earth. • GMR spin valve gradiometer arrays adapted for the evaluation of magnetic microstructures. • Magnetic stray fields are closely linked to microstructure of the material.
Study of Intestinal Helminthes of Stray Dogs and Thir Public Heath Importance in Hamadan City

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Kh. Rahmati

2016-11-01

Full Text Available Introduction: Intestinal helminthesof dogs are a serious threat to human health and may cause dangerous diseases such as: hydatidosis and visceral larva migrans, that which cause severe complications in human. Th aim of this study was to determine the prevalenceof intestinal helminthes of stray dogs in Hamadan city, Iran.. Methods: A total of 103 stray dogswere shot in the inner and around of the city in year 2015. Following necropsy, the intestines' contents of dogs were examined for helminthes macroscopically. Thn, the collected worms, aftr washing with saline,were counted and identifid according to being Nematode, Cestodeor Acantcephala. Thn, collected Nematodes were put in glass containers containing 70% ethanol-glycerine and Cestodes aftr processing on slides were put in the 10% formalin. To identify the species of helminthes, the Cestodes were stained using carmine acid and Nematodes were cleared in lacto-phenol. Results: Result indicated that, 74(71.8%stray dogs were infected at least by one species of intestinal helminthes. Th species of parasites were as follows: Echinococcus granulosus 37.9%, Dipylidium caninum 51.5%, Toxocara canis 19.4%, Taenia hydatigena 24.3%, T. multiceps 2.9%, T. ovis 1.9%, Mesocest oideslineatus 4.9%, and Acantho cephala 5.8%. Thre was no association between insex, season and region with prevalence of intestinal helminthes (P 0.05 between the prevalence of intestinal helminthes and dogs' age. Conclusions: Ths study indicatesd that,infection rate of helminthes in stray dogs is washigh in Hamadan city. Thse parasites are important in terms of human health and economic aspects. Threfore, it is more essential that public health authoritiesto develop control strategies for stray dogs population.
Gastrointestinal parasites in stray and shelter cats in the municipality of Rio de Janeiro, Brazil

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Pâmela Figueiredo Pereira

Full Text Available Abstract The increasingly urban nature of the population has led many people to choose independent pets, such as cats. This situation has also made it possible for these animals to be abandoned, thus increasing the numbers of cats on the streets and in shelters. These animals can act as a source of infection for other hosts. Between 2014 and 2015, the frequency of gastrointestinal parasites in captive and stray cats in the municipality of Rio de Janeiro was analyzed. Ninety-one fecal samples were collected from captive cats and 172 from stray cats. Centrifugal sedimentation and flotation techniques were used. The frequency of parasites among the stray cats was 77.3%, and this was significantly higher than the frequency observed in captive cats (49.5%. Helminths were detected more frequently, and hookworms were the parasites most detected. Toxocara cati, Cystoisospora sp. and Dipylidium caninum were also detected. No statistical difference in the frequency of parasites was observed between the sexes among the captive cats. However, among the stray cats, males (85.5% presented higher positivity than females (71.8%. The high frequency of hookworms, which are the agent for “cutaneous larva migrans” in humans, shows the need to control parasitic infections among the cats studied.
PCR-based molecular characterization of Toxocara spp. using feces of stray cats: a study from Southwest Iran.

Science.gov (United States)

Khademvatan, Shahram; Rahim, Fakher; Tavalla, Mahdi; Abdizadeh, Rahman; Hashemitabar, Mahmoud

2013-01-01

Feces of stray cat are potential sources of gastrointestinal parasites and play a crucial role in spreading and transmitting parasite eggs, larvae, and oocysts through contamination of soil, food, or water. In this study, we investigated the prevalence of Toxocara spp. infection in stray cats in Ahvaz city, southwest Iran. Eggs of Toxocara spp. in feces of stray cats were detected by the sucrose flotation method, and identification was conducted by polymerase chain reaction (PCR) and DNA sequencing. Of the 140 fecal samples that were randomly collected from public environments during the months of January to May 2012, 45% were found to harbour Toxocara spp. eggs. The highest prevalence of Toxocara spp. eggs was found in the central area of Ahvaz city (28.6%). T. canis eggs were found in 4 (6.34%) of the 63 positive samples. Stray cats are found in parks, playgrounds, and other public places and may be a potential contamination risk. Identification of Toxocara spp. using molecular methods is sufficiently sensitive to detect low levels of parasites and identify the different Toxocara spp. in feces. The relatively high prevalence of Toxocara spp. infection may continue to increase due to lack of effective environmental hygiene control in Iran. Consequently, there is a need to plan adequate programs to detect, identify, and control this infection as well as stray cats in the region.
PCR-based molecular characterization of Toxocara spp. using feces of stray cats: a study from Southwest Iran.

Directory of Open Access Journals (Sweden)

Shahram Khademvatan

Full Text Available Feces of stray cat are potential sources of gastrointestinal parasites and play a crucial role in spreading and transmitting parasite eggs, larvae, and oocysts through contamination of soil, food, or water. In this study, we investigated the prevalence of Toxocara spp. infection in stray cats in Ahvaz city, southwest Iran. Eggs of Toxocara spp. in feces of stray cats were detected by the sucrose flotation method, and identification was conducted by polymerase chain reaction (PCR and DNA sequencing. Of the 140 fecal samples that were randomly collected from public environments during the months of January to May 2012, 45% were found to harbour Toxocara spp. eggs. The highest prevalence of Toxocara spp. eggs was found in the central area of Ahvaz city (28.6%. T. canis eggs were found in 4 (6.34% of the 63 positive samples. Stray cats are found in parks, playgrounds, and other public places and may be a potential contamination risk. Identification of Toxocara spp. using molecular methods is sufficiently sensitive to detect low levels of parasites and identify the different Toxocara spp. in feces. The relatively high prevalence of Toxocara spp. infection may continue to increase due to lack of effective environmental hygiene control in Iran. Consequently, there is a need to plan adequate programs to detect, identify, and control this infection as well as stray cats in the region.
A review on stray current-induced steel corrosion in infrastructure

NARCIS (Netherlands)

Chen, Zhipei; Koleva, D.A.; van Breugel, K.

2017-01-01

Metallic corrosion can cause substantial damage at various levels and in almost all types of infrastructure. For metallic corrosion to occur, a certain external environment and the presence of corrodents are the prerequisites. Stray current-induced corrosion, however, is a rather underestimated
Experimental Study on the Influence of AC Stray Current on the Cathodic Protection of Buried Pipe

Directory of Open Access Journals (Sweden)

Qingmiao Ding

2016-01-01

Full Text Available The size of the damaged area of the coating and its position on the pipeline impacted the cathodic protection potential, and there was a damaged area of the greatest impact value. When damaged area was 300 mm2, the IR drop was the largest, and this situation could easily lead to inadequate protection; when the parallel spacing between pipeline and interference source was unchanged, the measured value curves of cathodic protection potential presented “U” shaped trend with the increasing stray current interference intensity. Under certain parallel spacing between pipeline and interference source, high alternating stray current intensity would cause serious negative offsets, so that the overprotection of the pipeline occurred, and make the coating crack; there was a parallel threshold length. When less than the threshold, the pipe-ground potential increases rapidly with the parallel length increasing. In order to judge whether a pipeline was interference by AC stray current and the risk of stray current corrosion, we should make a comprehensive analysis of the cathodic protection energizing potential, the switch-off potential, AC pipe-soil potential, IR drops, and so on.

What's in a name? Perceptions of stray and feral cat welfare and control in Aotearoa, New Zealand.

Science.gov (United States)

Farnworth, Mark J; Campbell, Joanna; Adams, Nigel J

2011-01-01

New Zealanders (n = 354) rated the acceptability of lethal and nonlethal cat control methods and the importance of conservation and welfare. Lethal control was more acceptable for feral cats than strays; for nonlethal control, the inverse was true. More than concern for the welfare of cats subjected to control, perceived conservation benefits, risk of disease transfer, and companion cat welfare dictated the acceptability of control measures. Similarly, the welfare consideration for groups of cats differed, transitioning from companion (highest) to feral (lowest). Differences in attitudes toward acceptability of control methods were evident. In particular, nonhuman animal professionals ranked lethal control as more acceptable than did nonanimal professionals. Cat caregivers (owners) considered both conservation and welfare issues of greater importance than did nonowners. Owners ranked the acceptability of nonlethal control methods higher for stray cats, but not feral, than did nonowners. This research indicates that the use of the terms stray and feral may have significant impact on cats in New Zealand. There is also a greater consideration of conservation values than of welfare in stray and feral cat control.
Molecular detection of blood pathogens and their impacts on levels of packed cell volume in stray dogs from Thailand

Directory of Open Access Journals (Sweden)

Supawadee Piratae

2017-04-01

Full Text Available Objective: To evaluate the prevalence of blood parasite infection in stray dogs by PCR technique and the association between levels of packed cell volume (PCV and blood parasitic infection in stray dogs. Methods: A total of 65 blood samples were collected from stray dogs in animal quarantine station from Mahasarakham, Thailand to evaluate the levels of PCV before molecular screening for tick-borne pathogens infection. Results: Stray dogs were positive with one or more pathogens in 44 (67.69% out of 65 blood samples. Ehrlichia canis [43.1%, 95% confidence interval (CI: 38.1–48.1] was the most common blood pathogen found infecting in stray dogs in Mahasarakham Province, followed by Anaplasma platys (29.2%, 95% CI: 24.2–34.2, Hepatozoon canis (12.3%, 95% CI: 7.3–17.3 and Babesia canis vogeli (6.2%, 95% CI: 1.2–11.2, respectively. Moreover, co-infections with two pathogens were identified in 11 (16.9% of dogs examined and two (2.9% dogs were coinfections with three pathogens. Statistically significant relationship between the PCV levels and Ehrlichia canis infection was found (P < 0.05. Conclusions: This study indicated that blood pathogens are spreading in stray dogs and they are potentially high risk of agent transmission to human via exposure with tick vectors. It was also the first report of Anaplasma platys infection in dogs in north-eastern part of Thailand.
Detection of Helminth Eggs and Identification of Hookworm Species in Stray Cats, Dogs and Soil from Klang Valley, Malaysia.

Science.gov (United States)

Tun, Sandee; Ithoi, Init; Mahmud, Rohela; Samsudin, Nur Izyan; Kek Heng, Chua; Ling, Lau Yee

2015-01-01

The present study was conducted to determine the prevalence of helminth eggs excreted in the faeces of stray cats, dogs and in soil samples. A total of 505 fresh samples of faeces (from 227 dogs and 152 cats) and soil were collected. The egg stage was detected via microscopy after the application of formalin-ether concentration technique. Genomic DNA was extracted from the samples containing hookworm eggs and used for further identification to the species level using real-time polymerase chain reaction coupled with high resolution melting analysis. Microscopic observation showed that the overall prevalence of helminth eggs among stray cats and dogs was 75.7% (95% CI = 71.2%-79.9%), in which 87.7% of dogs and 57.9% of cats were infected with at least one parasite genus. Five genera of heliminth eggs were detected in the faecal samples, including hookworms (46.4%), Toxocara (11.1%), Trichuris (8.4%), Spirometra (7.4%) and Ascaris (2.4%). The prevalence of helminth infections among stray dogs was significantly higher than that among stray cats (p dog hookworm, Ancylostoma caninum, was also detected among cats, which is the first such occurrence reported in Malaysia till date. This finding indicated that there was a cross-infection of A. caninum between stray cats and dogs because of their coexistent within human communities. Taken together, these data suggest the potential role of stray cats and dogs as being the main sources of environmental contamination as well as for human infections.
Counteracting Animal Homelessness and Providing Care for Stray Animals as a Task of a Commune

OpenAIRE

Szalewska, Małgorzata

2017-01-01

The analysis of Polish binding law acts allows one to assume that, on normative level, the obligation of public administration to provide care for stray animals is deeply embedded. Both the Animal Protection Act, as well as the Act on Maintaining Cleanliness, indicate the tasks of a commune in the scope of providing care for stray animals, catching homeless animals and counteracting their homelessness. Simultaneously, the analysis of jurisdiction, and inquiries as well as considerations emerg...
Stray dog meat consumption and rabies | Wiwanitkit | African Health ...

African Journals Online (AJOL)

Stray dog meat consumption and rabies. V Wiwanitkit. Abstract. No Abstract. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · http://dx.doi.org/10.4314/ahs.v14i3.41 · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians ...
Individual monitoring in high-energy stray radiation fields

International Nuclear Information System (INIS)

Hoefert, M.; Stevenson, G.R.

1995-01-01

Due to the lack of passive or active devices that could be considered as personal dosemeters in high-energy stray fields one can at present only perform individual monitoring around high energy accelerators. Of all detectors currently available it is shown that the NTA film is the most suitable method for individually monitoring the neutron exposure of more than 3000 persons regularly, reliably, and cost effectively like at CERN. (author)
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.
White light coronagraph in OSO-7

International Nuclear Information System (INIS)

Koomen, M.J.; Detwiler, C.R.; Brueckner, G.E.; Cooper, H.W.; Tousey, R.

1975-01-01

A small, externally occulted Lyot-type coronagraph, designated for use in the seventh unmanned Orbiting Solar Observatory (OSO-7), is described. Optical configuration, suppression of stray light, SEC vidicon detector, and data system are discussed, as well as integration of the instrument into the spacecraft and operation in orbit. Orbital operation produced daily images of the white light corona, from 2.8 to 10 solar radii, at least once per day for 2 3/4 yr. The first records of white light coronal transient events were obtained, and the corona was shown to be constantly changing
Optimization method of star tracker orientation for sun-synchronous orbit based on space light distribution.

Science.gov (United States)

Wang, Geng; Xing, Fei; Wei, Minsong; Sun, Ting; You, Zheng

2017-05-20

Star trackers, optical attitude sensors with high precision, are susceptible to space light from the Sun and the Earth albedo. Until now, research in this field has lacked systematic analysis. In this paper, we propose an installation orientation method for a star tracker onboard sun-synchronous-orbit spacecraft and analyze the space light distribution by transforming the complicated relative motion among the Sun, Earth, and the satellite to the body coordinate system of the satellite. Meanwhile, the boundary-curve equations of the areas exposed to the stray light from the Sun and the Earth albedo were calculated by the coordinate-transformation matrix under different maneuver attitudes, and the installation orientation of the star tracker was optimized based on the boundary equations instead of the traditional iterative simulation method. The simulation and verification experiment indicate that this installation orientation method is effective and precise and can provide a reference for the installation of sun-synchronous orbit star trackers free from the stray light.
Controlling stray electric fields on an atom chip for experiments on Rydberg atoms

Science.gov (United States)

Davtyan, D.; Machluf, S.; Soudijn, M. L.; Naber, J. B.; van Druten, N. J.; van Linden van den Heuvell, H. B.; Spreeuw, R. J. C.

2018-02-01

Experiments handling Rydberg atoms near surfaces must necessarily deal with the high sensitivity of Rydberg atoms to (stray) electric fields that typically emanate from adsorbates on the surface. We demonstrate a method to modify and reduce the stray electric field by changing the adsorbate distribution. We use one of the Rydberg excitation lasers to locally affect the adsorbed dipole distribution. By adjusting the averaged exposure time we change the strength (with the minimal value less than 0.2 V /cm at 78 μ m from the chip) and even the sign of the perpendicular field component. This technique is a useful tool for experiments handling Rydberg atoms near surfaces, including atom chips.
Feline immunodeficiency virus testing in stray, feral, and client-owned cats of Ottawa.

Science.gov (United States)

Little, Susan E

2005-10-01

Feline immunodeficiency virus (FIV) seroprevalence is evaluated in 3 groups of cats. Seventy-four unowned urban strays were tested, as well as 20 cats from a small feral cat colony, and 152 client-owned cats. Of the 246 cats tested, 161 (65%) were male and 85 (35%) were female. Seroprevalence for FIV was 23% in the urban strays, 5% in the feral cat colony, and 5.9% in the client-owned cats. Ten cats (4%) were also positive for Feline leukemia virus (FeLV) antigen, including 2 cats coinfected with FeLV and FIV. Seroprevalence for FIV in cats from Ottawa is similar to that found in other nonrandom studies of cats in North America.
Measurement of stray EC radiation on W7-AS

Science.gov (United States)

Gandini, F.; Hirsch, M.; Cirant, S.; Erckmann, V.; Granucci, G.; Kasparek, W.; Laqua, H. P.; Muzzini, V.; Nowak, S.; Radau, S.

2001-10-01

In the framework of a collaboration between IFP-CNR Milano, IPP Garching/Greifswald and IPF Stuttgart, a set of four millimeterwave probes has been installed in W7-AS stellarator at selected positions of the inner vessel wall. Their purpose is to observe RF stray radiation during operation in presence of strong level of Electron Cyclotron (EC) waves, used for plasma start-up, heating and current drive. The aim of these measurements is to benchmark two complementary theoretical models for the distribution of the stray radiation in the vessel. From these codes, quantitative predictions are expected for the spatial distribution of the RF wall load and the RF-impact on in-vessel components in large future devices such as W7-X and, possibly, ITER. This input is important to optimize the wall armour and select rf-compatible in-vessel materials. We present first measurements from different heating and startup scenarios, with up to 800 kW of injected power at 140 GHz and different launching geometries. An analysis of measurements performed on FTU using a previous version of sniffer probe is also presented.
Measurement of stray EC radiation on W7-AS

International Nuclear Information System (INIS)

Gandini, F.; Cirant, S.; Granucci, G.; Muzzini, V.; Nowak, S.; Hirsch, M.; Erckmann, V.; Laqua, H.P.; Radau, S.; Kasparek, W.

2001-01-01

In the framework of a collaboration between IFP-CNR Milano, IPP Garching/Greifswald and IPF Stuttgart, a set of four millimeterwave probes has been installed in W7-AS stellarator at selected positions of the inner vessel wall. Their purpose is to observe RF stray radiation during operation in presence of strong level of Electron Cyclotron (EC) waves, used for plasma start-up, heating and current drive. The aim of these measurements is to benchmark two complementary theoretical models for the distribution of the stray radiation in the vessel. From these codes, quantitative predictions are expected for the spatial distribution of the RF wall load and the RF-impact on in-vessel components in large future devices such as W7-X and, possibly, ITER. This input is important to optimize the wall armour and select rf-compatible in-vessel materials. We present first measurements from different heating and startup scenarios, with up to 800 kW of injected power at 140 GHz and different launching geometries. An analysis of measurements performed on FTU using a previous version of sniffer probe is also presented
Prevalence of intestinal helminth parasites in stray dogs in urban ...

African Journals Online (AJOL)

A total of 246 faecal samples were collected between October 2015 to February 2016, 154 from stray dogs in Harare and 92 from rural dogs in Arcturas, Goromonzi and Christon Bank. The samples were examined by flotation and sedimentation methods and helminth eggs identified and EPG counted. Of the 246 samples, ...
UV Blocking Glass: Low Cost Filters for Visible Light Photocatalytic Assessment

OpenAIRE

Dunnill, Charles W.

2014-01-01

A number of commercially available art protection products have been compared and assessed for their suitability as UV blocking filters in the application of “visible light” photocatalytic research. Many groups claiming visible light photocatalytic success employ filters to block out stray UV radiation in order to justify that their photocatalysts are indeed visible light photocatalysts and not UV light photocatalysts. These filters come in varying degrees of ability and price and many author...
MRI-related static magnetic stray fields and postural body sway: a double-blind randomized crossover study.

Science.gov (United States)

van Nierop, Lotte E; Slottje, Pauline; Kingma, Herman; Kromhout, Hans

2013-07-01

We assessed postural body sway performance after exposure to movement induced time-varying magnetic fields in the static magnetic stray field in front of a 7 Tesla (T) magnetic resonance imaging scanner. Using a double blind randomized crossover design, 30 healthy volunteers performed two balance tasks (i.e., standing with eyes closed and feet in parallel and then in tandem position) after standardized head movements in a sham, low exposure (on average 0.24 T static magnetic stray field and 0.49 T·s(-1) time-varying magnetic field) and high exposure condition (0.37 T and 0.70 T·s(-1)). Personal exposure to static magnetic stray fields and time-varying magnetic fields was measured with a personal dosimeter. Postural body sway was expressed in sway path, area, and velocity. Mixed-effects model regression analysis showed that postural body sway in the parallel task was negatively affected (P < 0.05) by exposure on all three measures. The tandem task revealed the same trend, but did not reach statistical significance. Further studies are needed to investigate the possibility of independent or synergetic effects of static magnetic stray field and time-varying magnetic field exposure. In addition, practical safety implications of these findings, e.g., for surgeons and others working near magnetic resonance imaging scanners need to be investigated. Copyright © 2012 Wiley Periodicals, Inc.
Detection of Helminth Eggs and Identification of Hookworm Species in Stray Cats, Dogs and Soil from Klang Valley, Malaysia.

Directory of Open Access Journals (Sweden)

Sandee Tun

Full Text Available The present study was conducted to determine the prevalence of helminth eggs excreted in the faeces of stray cats, dogs and in soil samples. A total of 505 fresh samples of faeces (from 227 dogs and 152 cats and soil were collected. The egg stage was detected via microscopy after the application of formalin-ether concentration technique. Genomic DNA was extracted from the samples containing hookworm eggs and used for further identification to the species level using real-time polymerase chain reaction coupled with high resolution melting analysis. Microscopic observation showed that the overall prevalence of helminth eggs among stray cats and dogs was 75.7% (95% CI = 71.2%-79.9%, in which 87.7% of dogs and 57.9% of cats were infected with at least one parasite genus. Five genera of heliminth eggs were detected in the faecal samples, including hookworms (46.4%, Toxocara (11.1%, Trichuris (8.4%, Spirometra (7.4% and Ascaris (2.4%. The prevalence of helminth infections among stray dogs was significantly higher than that among stray cats (p < 0.001. Only three genera of helminths were detected in soil samples with the prevalence of 23% (95% CI = 15.1%-31%, consisting of hookworms (16.6%, Ascaris (4% and Toxocara (2.4%. The molecular identification of hookworm species revealed that Ancylostoma ceylanicum was dominant in both faecal and soil samples. The dog hookworm, Ancylostoma caninum, was also detected among cats, which is the first such occurrence reported in Malaysia till date. This finding indicated that there was a cross-infection of A. caninum between stray cats and dogs because of their coexistent within human communities. Taken together, these data suggest the potential role of stray cats and dogs as being the main sources of environmental contamination as well as for human infections.
PENGARUH PEMBELAJARAN KOOPERATIF TWO STAY TWO STRAY BERPENDEKAT AN SETS TERHADAP HASIL BELAJAR KIMIA SISWA SMA NEGERI 1 COMAL

Directory of Open Access Journals (Sweden)

A. T. Setiawan

2016-07-01

Full Text Available Penelitian ini bertujuan untuk mengetahui pengaruh pembelajaran kooperatif two stay two stray berpendekatan SETS terhadap hasil belajar siswa. Desain eksperimen yang digunakan dalam penelitian ini adalah quasi experimental design. Hasil penelitian menunjukkan bahwa pembelajaran kooperatif two stay two stray berpendekatan SETS berpengaruh signitikan terhadap hasil belajar pada materi pokok teori asam basa dengan kontribusi koefisien determinasi sebesar 25%. Selain itu, pembelajaran juga mencapai ketuntasan belajar klasikal sebesar 37 dari 43 siswa, sehingga pembelajaran tersebut termasuk efektif.This study aimed to determine the effect of two stay two stray cooperative learning with SETS approach on student learning outcomes. Experimental design used in this study is a quasi experimental design. The results showed that two stay two stray cooperative learning with SETS approach have a significant effect on learning outcomes in acid-base theory of the subject matter with the contribution of the determination coefficient of 25%. In addition, the study also achieved mastery learning classical by 37 of the 43 students, so that it includes effective learning.
Gastrointestinal Helminths and Ectoparasites in the Stray Cats (Felidae: Felis catus) of Ahar Municipality, Northwestern Iran

Science.gov (United States)

YAKHCHALI, Mohammad; HAJIPOUR, Nasser; MALEKZADEH-VIAYEH, Reza; ESMAEILNEJAD, Bijan; NEMATI-HARAVANI, Taher; FATHOLLAHZADEH, Mohammad; JAFARI, Rasool

2017-01-01

Background: The stray cats are considered as the sources of emerging humans and domestic livestock pathogens and the zoonoses of public health importance. The present study was aimed to elucidate intestinal helminth infections and infestation with ectoparasites of the stray cats of Ahar City, northwestern Iran. Methods: Totally, 51 stray cats were randomly trapped from different parts of the city between Mar and Nov 2013. The cats were assessed for ectoparasites by hair brushing, skin scraping, acetate tape preparation and othic swabs. They were euthanized and inspected for helminths infection. Results: Overall prevalence of helminths and flea were 44/51 (86.3%) and 31/51 (60.78%), respectively. The infection rates were significantly different among different age groups (PDipylidium caninum (29.41%), T. hydatigena (19.6%)) were identified. The predominant infectious helminths in all the infected cats were T. cati (86.3% with egg per gram of feces 27.75±9). Of the 270 collected fleas, two species of Ctenocephalides felis (80%) and C. canis (20%) were notably frequent in the cats aged 2-3-year-old. The average number of fleas per each infected cat was recorded as 5.29, with no incidence of cross-infection. Conclusion: The results indicated the high rate of helminths infections and flea infestation in the urban stray cats of which Toxocara cati and Ctenocephalides felis may play important roles as zoonotic agents in the region. PMID:28761492
Potential Applicability of Persuasive Communication to Light-Glow Reduction Efforts: A Case Study of Marine Turtle Conservation

Science.gov (United States)

Kamrowski, Ruth L.; Sutton, Stephen G.; Tobin, Renae C.; Hamann, Mark

2014-09-01

Artificial lighting along coastlines poses a significant threat to marine turtles due to the importance of light for their natural orientation at the nesting beach. Effective lighting management requires widespread support and participation, yet engaging the public with light reduction initiatives is difficult because benefits associated with artificial lighting are deeply entrenched within modern society. We present a case study from Queensland, Australia, where an active light-glow reduction campaign has been in place since 2008 to protect nesting turtles. Semi-structured questionnaires explored community beliefs about reducing light and evaluated the potential for using persuasive communication techniques based on the theory of planned behavior (TPB) to increase engagement with light reduction. Respondents ( n = 352) had moderate to strong intentions to reduce light. TPB variables explained a significant proportion of variance in intention (multiple regression: R 2 = 0.54-0.69, P benefits to the local economy" ( P Selective legislation and commitment strategies may be further useful strategies to increase community light reduction. As artificial light continues to gain attention as a pollutant, our methods and findings will be of interest to anyone needing to manage public artificial lighting.

Gastrointestinal helminth parasites of pet and stray dogs as a potential risk for human health in Bahir Dar town, north-western Ethiopia

Directory of Open Access Journals (Sweden)

Tadiwos Abere

Full Text Available Aim: A cross-sectional study was carried out from November 2011 to April 2012 to determine the prevalence and species of gastrointestinal (GI helminth parasites in pet and stray dogs as a potential risk for human health in Bahir Dar town, northwestern Ethiopia. Materials and Methods: A total of 384 and 46 faecal samples were collected from pet and stray dogs, respectively and xamined by using standard coprologic techniques. Results: The overall prevalence of GI helminth infection in pet and stray dogs was 75.26 and 84.78%, respectively. The detected parasites with their frequencies in pet dogs were Ancylostoma caninum (78.89%, Toxocara canis (39.79%, Dipylidium caninum (29.75%, Strongyloides stercoralis (29.06%, Taeniidae (23.87% and Trichuris vulpis (7.95%. Stray dogs were found more likely to be polyparasitized and presented higher prevalence of A. caninum, T. canis, S. stercoralis, Trichuris vulpis and Taeniidae (P < 0.05 than domiciled ones. Diphyllobothrium latum was detected only in 10.25% of stray dogs. Toxocara canis and A. caninum (P < 0.05 were detected more frequently in dogs with less than 6 months of age (P <0.05 than old age dogs. The sex or breed groups didn't significantly affect the prevalence of parasites. A significant variation was recorded (P < 0.05 between different feeding systems where higher prevalence was observed in uncontrolled feeding group (82.18% compared to controlled feeding (32.08%. Conclusion: Different gastrointestinal parasites in pet and stray dogs were identified in the study area that can potentially infect humans and cause serious public-health problems. Thus, concerted efforts should therefore be made to educate dog owners to embrace modern dog disease control programs and measures have to be taken on stray dogs. [Vet World 2013; 6(7.000: 388-392
THE SOCIETY’S PERCEPTION OF THE LIFE QUALITY AND POPULATION CONTROL OF STRAY DOGS

Directory of Open Access Journals (Sweden)

Flavio Fernando Batista Moutinho

2015-10-01

Full Text Available In most Brazilian municipalities there is an overpopulation of stray dogs, which causes problems to the urban order, the environment and the public health, in addition to mistreatment to these dogs. In such context we foresee the need of developing actions targeting the population control of these animals. This essay aims at knowing the perception of social actors, such as managers of entities responsible for control actions, managers of NGOs working with animal protection and population in general with respect to the life quality and population control of stray dogs. Questionnaires were used on samples of individuals of these three groups and the data thereof were analyzed with descriptive statistics techniques and frequency comparison. The results allowed us to conclude that the society’s perception of population control and life quality of these animals bear important differences under the viewpoint of the three evaluated groups; however, they also bear significant similarities, especially with respect to the perception of the responsibility for the development of population control actions, the acceptance of using public funds intended to public health in control actions, the classification of such population density as large and the poor life quality of these animals. population control, social perception, stray dog.,
Effect of stray current on corrosion behavior of reinforcing steel: importance of cell geometry and orientation with respect to the electrical field

NARCIS (Netherlands)

Chen, Zhipei; Koleva, D.A.

2016-01-01

Stray current circulating in reinforced concrete structures may initiate corrosion or accelerate existing corrosion processes on embedded reinforcement. In some cases, the range of dangerous or unwanted interactions of stray currents under favorable conditions (environment), is much broader than is
IMPLEMENTASI MODEL PEMBELAJARAN TWO STAY TWO STRAY DALAM PEMBELAJARAN BERBASIS KEMAMPUAN BERPIKIR KRITIS KELAS V SD

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M. Yusuf Setia Wardana

2017-04-01

Full Text Available Benefits of mathematics are to equip students with the ability to think logically, analytical, systematically, critically, and creatively, as well as the ability to cooperate. Based on observations in elementary school, there are 40% of students have not reached KKM and students have lack of critical abilities to understand math problems, and they have low activity of the study. One of models that can be applied is Two Stay Two Stray. The study used True Experimental Design with Posttest-Only Control Design. The population in this study was all fifth grade students of SD Negeri Semarang Rejosari 03. Data of critical thinking skills of the students in average on test of critical thinking skills mastery was 3.31 ≥ 2.67, it can be said to have a complete description. The conclusion is a model of Two Stay Two Stray being effective for critical thinking skills and mathematics learning outcomes of fifth grade students in SD Negeri Rejosari 03 Semarang. Keywords: two stay two stray model, critical thinking ability.
Symptoms and Cognitive Effects of Exposure to Magnetic Stray Fields of MRI Scanners

NARCIS (Netherlands)

Vocht, Frank Gérard de

2006-01-01

People working routinely with magnetic resonance imaging (MRI) systems report a number of symptoms related to their presence in the inhomogeneous static magnetic fields (the stray field) surrounding these scanners. Experienced symptoms and neurobehavioral performance among engineers manufacturing
Stray cats are more frequently infected with zoonotic protists than pet cats.

Science.gov (United States)

Kvac, Martin; Hofmannova, Lada; Ortega, Ynes; Holubova, Nikola; Horcickova, Michaela; Kicia, Marta; Hlaskova, Lenka; Kvetonova, Dana; Sak, Bohumil; McEvoy, John

2017-12-06

Faecal samples were collected from cats kept as pets (n = 120) and stray cats (n = 135) in Central Europe (Czech Republic, Poland and Slovakia) and screened for the presence of Cryptosporidium spp., Giardia intestinalis (Kunstler, 1882), Encephalitozoon spp. and Enterocytozoon bieneusi Desportes, Le Charpentier, Galian, Bernard, Cochand-Priollet, Lavergne, Ravisse et Modigliani, 1985 by PCR analysis of the small-subunit of rRNA (Cryptosporidium spp. and G. intestinalis) and ITS (microsporidia) genes. Sequence analysis of targeted genes revealed the presence of C. felis Iseki, 1979, G. intestinalis assemblage F, E. cuniculi Levaditi, Nicolau et Schoen, 1923 genotype II, and E. bieneusi genotype D. There was no correlation between the occurrence of detected parasites and sex, presence of diarrhoea or drug treatment (drug containing pyrantel and praziquantel). Compared to pet cats (7%), stray cats (30%) were statistically more frequently infected with protist parasites and overall may present a greater risk to human health.
Stray Cats Gastrointestinal Parasites and its Association With Public Health in Ahvaz City, South Western of Iran

Science.gov (United States)

Khademvatan, Shahram; Abdizadeh, Rahman; Rahim, Fakher; Hashemitabar, Mahamoud; Ghasemi, Mohammad; Tavalla, Mahdi

2014-01-01

Background: Cats are the hosts for some zoonotic parasites such as Toxoplasma gondii and Toxocara spp. which are important in medicine and veterinary. Studies on the prevalence of intestinal parasites of cats have received little attention in south west of Iran. Objectives: The current study aimed to investigate the prevalence of parasites in stray cats in Ahvaz. Materials and Methods: Random sampling was carried out from January to May 2012. One hundred and forty fecal samples from stray cats were examined using sucrose flotation method. Results: Gastrointestinal parasites were found in 121 of the 140 (86.4%) examined samples. The parasites detected in stray cats were Toxocara spp. (45%, 63/140), Isospora spp. (21.4%, 30/140), nematode larvae (21.4%, 30/140), Taenia spp. (18.6%, 26/140), Sarcocystis spp. (17.1%, 24/140), Eimeria spp. (15%, 21/140), Blastocystis spp. (14.3%, 20/140), Giardia spp, (10.7%, 15/140), Physaloptera spp. (7.1%, 10/140), and amoeba cyst (5.7%, 8/140) respectively. The prevalence of infection by Joyexiella spp. and hook worms (4.3%, 6/140), for example, Dipylidium caninum (2.9%, 4/140) was similar; and the prevalence of infection by T. gondii and Dicrocoelium dendriticum was similar (1.4%, 2/140). Conclusions: Since the prevalence of zoonotic gastrointestinal parasites such as Toxocara spp. in stray cats is high, there is a need to plan adequate programs to control these zoonotic parasites. PMID:25485047
Stray dogs and cats as potential sources of soil contamination with zoonotic parasites

Directory of Open Access Journals (Sweden)

Katarzyna Szwabe

2017-03-01

Cat faeces represent a more important potential source of environmental contamination with zoonotic parasites than dog faeces. Among the detected parasites of stray dogs and cats, Toxocara present an important zoonotic risk for the local human population, especially children.
Evaluation of stray radiofrequency radiation emitted by electrosurgical devices

International Nuclear Information System (INIS)

De Marco, M; Maggi, S

2006-01-01

Electrosurgery refers to the passage of a high-frequency, high-voltage electrical current through the body to achieve the desired surgical effects. At the same time, these procedures are accompanied by a general increase of the electromagnetic field in an operating room that may expose both patients and personnel to relatively high levels of radiofrequency radiation. In the first part of this study, we have taken into account the radiation emitted by different monopolar electrosurgical devices, evaluating the electromagnetic field strength delivered by an electrosurgical handle and straying from units and other electrosurgical accessories. As a summary, in the worst case a surgeon's hands are exposed to a continuous and pulsed RF wave whose magnetic field strength is 0.75 A m -1 (E-field 400 V m -1 ). Occasionally stray radiation may exceed ICNIRP's occupational exposure guidelines, especially close to the patient return plate. In the second part of this paper, we have analysed areas of particular concern to prevent electromagnetic interference with some life-support devices (ventilators and electrocardiographic devices), which have failed to operate correctly. Most clinically relevant interference occurred when an electrosurgery device was used within 0.3 m of medical equipment. In the appendix, we suggest some practical recommendations intended to minimize the potential for electromagnetic hazards due to therapeutic application of RF energy
Gastrointestinal and ectoparasites from urban stray dogs in Fortaleza (Brazil): high infection risk for humans?

Science.gov (United States)

Klimpel, Sven; Heukelbach, Jörg; Pothmann, David; Rückert, Sonja

2010-08-01

Dogs are important definite or reservoir hosts for zoonotic parasites. However, only few studies on the prevalence of intestinal parasites in urban areas in Brazil are available. We performed a comprehensive study on parasites of stray dogs in a Brazilian metropolitan area. We included 46 stray dogs caught in the urban areas of Fortaleza (northeast Brazil). After euthanization, dogs were autopsied. Ectoparasites were collected, and the intestinal content of dogs were examined for the presence of parasites. Faecal samples were collected and analysed using merthiolate iodine formaldehyde concentration method. A total of nine different parasite species were found, including five endoparasite (one protozoan, one cestode and three nematode species) and four ectoparasite species (two flea, one louse and one tick species). In the intestinal content, 3,162 specimens of four helminth species were found: Ancylostoma caninum (prevalence, 95.7%), Dipylidium caninum (45.7%), Toxocara canis (8.7%) and Trichuris vulpis (4.3%). A total of 394 ectoparasite specimens were identified, including Rhipicephalus sanguineus (prevalence, 100.0%), Heterodoxus spiniger (67.4%), Ctenocephalides canis (39.1%) and Ctenocephalides felis (17.4%). In the faeces, intestinal parasites were detected in 38 stray dogs (82.6%), including oocysts of Giardia sp. (2.2%) and eggs of the nematode A. caninum (82.6%). Neither eggs nor larval stages of D. caninum, T. canis or T. vulpis were detected in dog faeces. Sensitivity of faecal examination for A. caninum was 86.4% (95% confidence interval, 72.0-94.3) but zero percentage for the other intestinal helminth species. Our data show that stray dogs in northeast Brazil carry a multitude of zoonotic ecto- and endoparasites, posing a considerable risk for humans. With the exception of A. caninum, sensitivity of faecal examination was negligible.
Molecular detection of Ehrlichia canis, Hepatozoon canis and Babesia canis vogeli in stray dogs in Mahasarakham province, Thailand.

Science.gov (United States)

Piratae, Supawadee; Pimpjong, Kiattisak; Vaisusuk, Kotchaphon; Chatan, Wasupon

2015-01-01

Canine tick borne diseases showing distribution worldwide have caused morbidity and mortality in dogs. This study observed the mainly tick borne pathogens described for dogs in Thailand, Ehrlichia canis, Hepatozoon canis and Babesia canis vogeli. From May to July 2014, blood samples were collected from 79 stray dogs from 7 districts of Mahasarakham province to molecular surveyed for 16s rRNA gene of E. canis and 18s rRNA gene of H. canis and B. canis vogeli. Twenty eight (35.44%) of stray dogs showed the infection with tick borne pathogens. The prevalence of E. canis infection was the highest with 21.5% (17/79). DNA of H. canis and B. canis vogeli were detected at the prevalence of 10.1% (8/79) and 6.3% (5/79), respectively. Co-infection between E. canis and B. canis vogeli were identified in 2 (2.5%) dogs. The results indicated that a wide range of tick borne pathogens are circulation in the canine population in Mahasarakham province. This study is the first report on prevalence of E. canis, H. canis and B. canis vogeli in stray dogs in Mahasarakham, a province in northern part of Thailand. This data providing is important to understand the prevalence of E. canis, H. canis and B. canis vogeli infection in stray dogs in this region, which will assist in the management of these blood parasite.
An estimate of the radiation-induced cancer risk from the whole-body stray radiation exposure in neutron radiotherapy

International Nuclear Information System (INIS)

Geraci, J.P.; Jackson, K.L.; Mariano, M.S.

1982-01-01

1980 BEIR III risk factors have been used to estimate the secondary cancer risks from the whole-body stray radiation exposures occurring in neutron radiotherapy. Risks were calculated using linear, linear-quadratic and quadratic dose-response models for the gamma component of the stray radiation. The linear dose-response model was used to calculate risk for the neutron component of the stray radiation. These estimates take into consideration for the first time the age and sex distribution of patients undergoing neutron therapy. Changes in risk as a function of the RBE (10-100) assigned to the stray neutron radiation component have also been assessed. Excess risks in neutron-treated patients have been compared with excess risks for photon-treated patients and with the expected incidence of cancer in a normal population having the same age and sex distribution. Results indicate that it will be necessary to tolerate a higher incidence of secondary cancers in patients undergoing fast neutron therapy than is the case with conventional photon therapy. For neutron RBEs of less than 50 the increased risk is only a fraction of the normal expected incidence of cancer in this population. Comparison of the radiation-induced risk with reported normal tissue complication rates in the treatment volume indicates that the excess cancer risk is substantially lower than the risk from other late normal tissue effects. (author)
Shielding of the NBI boxes against W7-X magnetic stray fields

Energy Technology Data Exchange (ETDEWEB)

Kick, Manfred [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstr. 2, D-85748 Garching (Germany)], E-mail: Kick@arcor.de; Sielanko, Juliusz [Maria Curie Sklodowska University, Pl. M. C. Sklodowskie 1, 20-031 Lublin (Poland); Heinemann, Bernd; Riedl, Rudolf; Speth, Eckehart; Staebler, Albrecht [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstr. 2, D-85748 Garching (Germany)

2009-06-15

Neutral Beam Injection (NBI), besides ECRH, is foreseen as one of the main heating devices at the W7-X stellarator currently under construction at IPP Greifswald, Germany. In a final stage 20 MW of NBI heating power will be installed generated by two NBI boxes of the ASDEX Upgrade (AUG) type. Since magnetic fields generally affect the trajectories of charged particles, essentially all the NBI boxes - including ion sources, acceleration sections, neutralisers and deflection magnets - must be shielded against the stray fields of W7-X. In the magnetic stray fields of W7-X there exist significant radial and toroidal components whereas at tokamaks the vertical components are dominant. The power loads on the ion dump and the protecting structures of the deflecting magnets and the beam lines caused by residual beam ions, therefore, will be strongly different. Thus the shielding concept of AUG cannot simply be taken over, but must be carefully redesigned in order to remain below the critical power limits. New modelling calculations of the magnetic shielding, the ion trajectories and the resulting power loads have been carried out for the 'high iota' and 'low shear' experimental scenarios of W7-X. The fields taken for these calculations are modelled by averaging the calculated W7-X stray fields on the one hand, and by fields generated by two-hypothetical-planar coils perpendicular to the x-y plane, on the other hand. The shielding concept for W7-X mainly consist of iron plates in the outer side regions of the boxes and as little magnetic material as possible inside the boxes.
Anti-glare LED lamps with adjustable illumination light field.

Science.gov (United States)

Chen, Yung-Sheng; Lin, Chung-Yi; Yeh, Chun-Ming; Kuo, Chie-Tong; Hsu, Chih-Wei; Wang, Hsiang-Chen

2014-03-10

We introduce a type of LED light-gauge steel frame lamp with an adjustable illumination light field that does not require a diffusion plate. Base on the Monte Carlo ray tracing method, this lamp has a good glare rating (GR) of 17.5 at 3050 lm. Compared with the traditional LED light-gauge steel frame lamp (without diffusion plate), the new type has low GR. The adjustability of the illumination light field could improve the zebra effect caused by the inadequate illumination light field of the lamp. Meanwhile, we adopt the retinal image analysis to discuss the influence of GR on vision. High GR could reflect stray light on the retinal image, which will reduce vision clarity and hasten the feeling of eye fatigue.
Stray animal populations and public health in the South Mediterranean and the Middle East regions

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Aristarhos Seimenis

2014-06-01

Full Text Available Uncontrolled urban growth in South Mediterranean and the Middle East regions involves city dwellers and stray animals (mainly dogs and cats creating a dense and downgraded environment, in which irregular street garbage collection disposes sufficient food for survival and proliferation of stray animals. Under such conditions serious public health hazards are expected due to the increase of animal bites, the multiplication of insects and rodents vectors of different viral, bacterial, fungal and parasitic agents to which humans are exposed. Traditional national stray animal eradication programs and occasional small animals' humane elimination campaigns are insufficient to avert human and veterinary health risks when not coupled with modern technologies. In such environments, multiple foci of emerging and re‑emerging zoonoses easily spread, i.e. rabies, hydatidosis, leishmaniasis and toxoplasmosis. Upgrading urban and peri-urban situations requires integrated/coordinated management programmes, in which public and animal health services as well as municipalities have a crucial role. Control and upgrading programmes should be flexible and able to adapt to the specific conditions of the given country/region. In this context, intersectoral/interprofessional collaborations and community participation are crucial for any national and regional development strategies. In this respect, a global approach considering both public health and socio-economic problems shows to be extremely adequate and effective.
Problems Associated with the Microchip Data of Stray Dogs and Cats Entering RSPCA Queensland Shelters

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Emily Lancaster

2015-05-01

Full Text Available A lack of published information documenting problems with the microchip data for the reclaiming of stray animals entering Australian shelters limits improvement of the current microchipping system. A retrospective study analysing admission data for stray, adult dogs (n = 7258 and cats (n = 6950 entering the Royal Society for the Prevention of Cruelty to Animals (RSPCA Queensland between January 2012 and December 2013 was undertaken to determine the character and frequency of microchip data problems and their impact on outcome for the animal. Only 28% of dogs and 9% of cats were microchipped, and a substantial proportion (37% had problems with their data, including being registered to a previous owner or organisation (47%, all phone numbers incorrect/disconnected (29%, and the microchip not registered (14%. A higher proportion of owners could be contacted when the microchip had no problems, compared to those with problems (dogs, 93% vs. 70%; cats, 75% vs. 41%. The proportion of animals reclaimed declined significantly between microchipped animals with no data problems, microchipped animals with data problems and non-microchipped animals—87%, 69%, and 37%, respectively, for dogs and 61%, 33%, and 5%, respectively, for cats. Strategies are needed to increase the accuracy of microchip data to facilitate the reclaiming of stray dogs and cats.
Reduction of Cr(VI) to Cr(III) using silicon nanowire arrays under visible light irradiation

Energy Technology Data Exchange (ETDEWEB)

Fellahi, Ouarda [Institut d' Electronique, de Microélectronique et de Nanotechnologie (IEMN), UMR CNRS 8520, Avenue Poincaré—BP 70478, 59652 Villeneuve d' Ascq Cedex (France); Centre de Recherche en Technologie des Semi-conducteurs pour l' Energétique-CRTSE 02, Bd Frantz Fanon, BP. 140, Alger 7 Merveilles (Algeria); Barras, Alexandre [Institut d' Electronique, de Microélectronique et de Nanotechnologie (IEMN), UMR CNRS 8520, Avenue Poincaré—BP 70478, 59652 Villeneuve d' Ascq Cedex (France); Pan, Guo-Hui [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, 3888 Dong Nanhu Road, Changchun 130033 (China); Coffinier, Yannick [Institut d' Electronique, de Microélectronique et de Nanotechnologie (IEMN), UMR CNRS 8520, Avenue Poincaré—BP 70478, 59652 Villeneuve d' Ascq Cedex (France); Hadjersi, Toufik [Centre de Recherche en Technologie des Semi-conducteurs pour l' Energétique-CRTSE 02, Bd Frantz Fanon, BP. 140, Alger 7 Merveilles (Algeria); Maamache, Mustapha [Laboratoire de Physique Quantique et Systèmes Dynamiques, Département de Physique, Université de Sétif, Sétif 19000 (Algeria); Szunerits, Sabine [Institut d' Electronique, de Microélectronique et de Nanotechnologie (IEMN), UMR CNRS 8520, Avenue Poincaré—BP 70478, 59652 Villeneuve d' Ascq Cedex (France); and others

2016-03-05

Highlights: • Cr(VI) reduction to Cr(III) using silicon nanowires decorated with Cu nanoparticles. • The reduction takes place at room temperature and neutral pH under visible light. • The photocatalytic reduction was enhanced by addition of adipic or citric acid. - Abstract: We report an efficient visible light-induced reduction of hexavalent chromium Cr(VI) to trivalent Cr(III) by direct illumination of an aqueous solution of potassium dichromate (K{sub 2}Cr{sub 2}O{sub 7}) in the presence of hydrogenated silicon nanowires (H-SiNWs) or silicon nanowires decorated with copper nanoparticles (Cu NPs-SiNWs) as photocatalyst. The SiNW arrays investigated in this study were prepared by chemical etching of crystalline silicon in HF/AgNO{sub 3} aqueous solution. The Cu NPs were deposited on SiNW arrays via electroless deposition technique. Visible light irradiation of an aqueous solution of K{sub 2}Cr{sub 2}O{sub 7} (10{sup −4} M) in presence of H-SiNWs showed that these substrates were not efficient for Cr(VI) reduction. The reduction efficiency achieved was less than 10% after 120 min irradiation at λ > 420 nm. Addition of organic acids such as citric or adipic acid in the solution accelerated Cr(VI) reduction in a concentration-dependent manner. Interestingly, Cu NPs-SiNWs was found to be a very efficient interface for the reduction of Cr(VI) to Cr(III) in absence of organic acids. Almost a full reduction of Cr(VI) was achieved by direct visible light irradiation for 140 min using this photocatalyst.
Gastrointestinal Helminths and Ectoparasites in the Stray Cats (Felidae: Felis catus of Ahar Municipality, Northwestern Iran

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Mohammad YAKHCHALI

2017-06-01

Full Text Available Background: The stray cats are considered as the sources of emerging humans and domestic livestock pathogens and the zoonoses of public health importance. The present study was aimed to elucidate intestinal helminth infections and infestation with ectoparasites of the stray cats of Ahar City, northwestern Iran.Methods: Totally, 51 stray cats were randomly trapped from different parts of the city between Mar and Nov 2013. The cats were assessed for ectoparasites by hair brushing, skin scraping, acetate tape preparation and othic swabs. They were euthanized and inspected for helminths infection.Results: Overall prevalence of helminths and flea were 44/51 (86.3% and 31/51 (60.78%, respectively. The infection rates were significantly different among different age groups (P<0.05. Of the 282 isolated helminths, three species of nematodes (Toxocara cati (86.3%, T. leonina (11.77%, Ancylostoma tubaeforme (5.9% and four species of cestodes (Taenia taeniaeformis (64.7%, Mesocestoides lineatus (49.02%, Dipylidium caninum (29.41%, T. hydatigena (19.6% were identified. The predominant infectious helminths in all the infected cats were T. cati (86.3% with egg per gram of feces 27.75±9. Of the 270 collected fleas, two species of Ctenocephalides felis (80% and C. canis (20% were notably frequent in the cats aged 2-3-year-old. The average number of fleas per each infected cat was recorded as 5.29, with no incidence of cross-infection.Conclusion: The results indicated the high rate of helminths infections and flea infestation in the urban stray cats of which Toxocara cati and Ctenocephalides felis may play important roles as zoonotic agents in the region.
Monitoring DC stray current interference of steel sheet pile structures in railway environment

NARCIS (Netherlands)

Peelen, W.H.A.; Neeft, E.A.C.; Leegwater, G.; Kanten-Roos, W. van; Courage, W.M.G.

2011-01-01

Steel structures near DC powered railways are expected to be affected by stray current interference. This causes accelerated corrosion rates. Therefore steel is often not used as a building material in these cases, although certain advantages over the alternative material concrete exist. These
Seroprevalence and Risk Factors Associated with Seropositivity to Toxoplasma gondii among Stray and Domestic Cats (Felis silvestris catus

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Christel Bohn T. Garcia

2014-12-01

Full Text Available Toxoplasma gondii is a protozoan parasite that causes toxoplasmosis. It is widespread in the environment and infects a variety of warm-blooded animals, causing miscarriages and birth problems. Previous studies in the Philippines have determined the seropositivity of T. gondii in humans. However, the seroprevalence of the parasite among household pets, par ticularly its feline def initive host, remains insufficient . This study aimed to: (1 determine the seroprevalence of T. gondii antibodies among domestic and stray cats in the Philippines; and, (2 to analyze the risk factors associated with seropositivity. Blood samples from 59 domestic and stray cats were collected and tested for T. gondii seropositivity using a commercially available indirect ELISA kit, while pet owners and handlers were given questionnaires about their cats. Thirteen or 22.03% of the cats were seropositive to T. gondii, and risk factor analysis revealed a significant difference between domestic and stray cats with regard to diet (p = 0.026, OR = 8.333, c = 0.299 and domestication (p = 0.039, OR = 5.000, c = 0.276. Cats fed with table food tested 31.43% seropositive compared to the 4.35% of those fed with cat food, whereas 33.33% of the stray cats were seropositive compared to 7.69% for domestic cats. Odds ratio test showed that the risk factors studied were associated with higher likelihood of T. gondii seropositivity. These results implicate diet and environment in the transmission dynamics of T. gondii among cats.

Rf Discharge Impedance Measurements Using a New Method to Determine the Stray Impedances

NARCIS (Netherlands)

Bakker, L.P.; Kroesen, G.M.W.; Hoog, de F.J.

1999-01-01

The impedance of a capacitively coupled radio frequency discharge in a tubular fluorescent lamp filled with neon and mercury is measured. The stray impedances in the electrical network are determined using a new method that requires no extra instruments. The reflection of power is used to determine
Light-driven dinitrogen reduction catalyzed by a CdS:nitrogenase MoFe protein biohybrid

Energy Technology Data Exchange (ETDEWEB)

Brown, K. A.; Harris, D. F.; Wilker, M. B.; Rasmussen, A.; Khadka, N.; Hamby, H.; Keable, S.; Dukovic, G.; Peters, J. W.; Seefeldt, L. C.; King, P. W.

2016-04-21

The splitting of dinitrogen (N2) and reduction to ammonia (NH3) is a kinetically complex and energetically challenging multistep reaction. In the Haber-Bosch process, N2 reduction is accomplished at high temperature and pressure, whereas N2 fixation by the enzyme nitrogenase occurs under ambient conditions using chemical energy from adenosine 5'-triphosphate (ATP) hydrolysis. We show that cadmium sulfide (CdS) nanocrystals can be used to photosensitize the nitrogenase molybdenum-iron (MoFe) protein, where light harvesting replaces ATP hydrolysis to drive the enzymatic reduction of N2 into NH3. The turnover rate was 75 per minute, 63% of the ATP-coupled reaction rate for the nitrogenase complex under optimal conditions. Inhibitors of nitrogenase (i.e., acetylene, carbon monoxide, and dihydrogen) suppressed N2 reduction. The CdS:MoFe protein biohybrids provide a photochemical model for achieving light-driven N2 reduction to NH3.
Decoding of digital magnetic recording with longitudinal magnetization of a tape from a magneto-optical image of stray fields

Science.gov (United States)

Lisovskii, F. V.; Mansvetova, E. G.

2017-05-01

For digital magnetic recording of encoded information with longitudinal magnetization of the tape, the connection between the domain structure of a storage medium and magneto-optical image of its stray fields obtained using a magnetic film with a perpendicular anisotropy and a large Faraday rotation has been studied. For two-frequency binary code without returning to zero, an algorithm is developed, that allows uniquely decoding of the information recorded on the tape based on analysis of an image of stray fields.
Matrix light and pixel light: optical system architecture and requirements to the light source

Science.gov (United States)

Spinger, Benno; Timinger, Andreas L.

2015-09-01

Modern Automotive headlamps enable improved functionality for more driving comfort and safety. Matrix or Pixel light headlamps are not restricted to either pure low beam functionality or pure high beam. Light in direction of oncoming traffic is selectively switched of, potential hazard can be marked via an isolated beam and the illumination on the road can even follow a bend. The optical architectures that enable these advanced functionalities are diverse. Electromechanical shutters and lens units moved by electric motors were the first ways to realize these systems. Switching multiple LED light sources is a more elegant and mechanically robust solution. While many basic functionalities can already be realized with a limited number of LEDs, an increasing number of pixels will lead to more driving comfort and better visibility. The required optical system needs not only to generate a desired beam distribution with a high angular dynamic, but also needs to guarantee minimal stray light and cross talk between the different pixels. The direct projection of the LED array via a lens is a simple but not very efficient optical system. We discuss different optical elements for pre-collimating the light with minimal cross talk and improved contrast between neighboring pixels. Depending on the selected optical system, we derive the basic light source requirements: luminance, surface area, contrast, flux and color homogeneity.
An epidemiological survey on intestinal helminths of stray dogs in Mashhad, North-east of Iran.

Science.gov (United States)

Emamapour, Seyed Rasoul; Borji, Hassan; Nagibi, Abolghasem

2015-06-01

This research was conducted to determine the prevalence of gastrointestinal helminths in stray dogs in the northeast of Iran, with special attention to those parasites that can be transmitted to human. In this experiment, a total of 72 adult and 18 juvenile stray dogs were collected and necropsied for the presence of helminth parasites from October 2011 to August 2012. The overall prevalence of gastrointestinal helminths was 86 % (95 % CI: 79.2-92.8 %). The observed helminths of the gastrointestinal tract were listed as follows: Toxocara canis (29 %), Toxascaris leonina (7 %), Ancylostoma caninum (2 %), Taenia hydatigena (43 %), Dipylidium caninum (39 %), Echinococcus granulosus (38 %), Mesocestoides lineatus (16 %), Taenia multiceps (11 %), Taenia ovis (3 %). There were no significant differences for the prevalence of gastrointestinal helminths between female (83.6 %) and male (89.7 %) and between young (89 %) and adult (72.2 %) animals. However, the prevalence of E. granulosus, T. hydatigena and D. caninum showed an increasing trend with increasing host age, significantly. Based on our data, it is important to point out the presence of zoonotic agents, namely E. granulosus and T. canis in stray dogs in the investigated area. Due to its impact on public health, appropriate control measures should be taken and it is recommended to determine the most appropriate preventive methods.
Experimental investigation of the ECRH stray radiation during the start-up phase in Wendelstein 7-X

Science.gov (United States)

Moseev, Dmitry; Laqua, Heinrich; Marsen, Stefan; Stange, Torsten; Braune, Harald; Erckmann, Volker; Gellert, Florian; Oosterbeek, Johann Wilhelm; Wenzel, Uwe

2017-07-01

Electron cyclotron resonance heating (ECRH) is the main heating mechanism in the Wendelstein 7-X stellarator (W7-X). W7-X is equipped with five absolutely calibrated sniffer probes that are installed in each of the five modules of the device. The sniffer probes monitor energy flux of unabsorbed ECRH radiation in the device and interlocks are fed with the sniffer probe signals. The stray radiation level in the device changes significantly during the start-up phase: plasma is a strong microwave absorber and during its formation the stray radiation level in sniffer probes reduces by more than 95%. In this paper, we discuss the influence of neutral gas pressure and gyrotron power on plasma breakdown processes.
Prevalence of Protozoa and Gastrointestinal Helminthes in Stray Cats in Zanjan Province, North-West of Iran

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SA Altome

2009-07-01

Full Text Available Background: Cats and other felines act as definitive hosts for many intestinal parasites, some of which are responsible for several zoonotic diseases. The aim of this study was to determine the type and prevalence of protozoa and gastrointestinal helminthes among stray cats. Methods: A cross sectional study was conducted. Digestive tracts of 100 stray cats in Zanjan Province, north-west of Iran were autopsied in order to recognize gastrointestinal helminthes and intestinal protozoan parasites. These cats were collected by baited cage trapped from October 2007 to September 2008. Gender and species of helminthes and protozoa were recognized using authentic diagnostic criteria. Statistical evaluation was performed by SPSS version 14. Results: Forty-two percent of cats were infected with intestinal protozoan parasites, 33% were infected with cestodes and 39% infected with gastrointestinal nematodes. Four species protozoan parasites and eight gastrointestinal helminthes were recovered from the animals, including Taenia taeniaeformis, Dipylidium spp., Joyeuxiella pasqaulei, Toxocara cati, Physaloptera praeputialis, Rectalaria spp., Onicolla, Cystoisospora spp., Toxoplasma gondii, and Sarcocystis spp . Conclusions: The high infection rate of Toxoplasma and some gastrointestinal helminthes in stray cats is considered to be critical from the viewpoint of public health importance.
Prevalence of zoonotic intestinal parasites in household and stray dogs in rural areas of Hamadan, Western Iran.

Science.gov (United States)

Sardarian, K; Maghsood, A H; Ghiasian, S A; Zahirnia, A H

2015-06-01

Zoonotic parasitic infections are a major global public and veterinary health problem and widespread among dogs. The objective of this study was to assess the prevalence of intestinal parasites in stray and household dogs in the rural areas of Hamadan district. During 2012, 1,500 fresh fecal samples from 243 household and 1,257 stray dogs were examined by using direct wet mount, simple zinc sulfate flotation, and Lugol's solution staining. Of 1,500 dogs, 20.4% were positive for intestinal parasites. Helminthes eggs were more frequently found in fecal samples than protozoan cysts or trophozoites (15.9% vs. 4.5%, respectively). Toxocara canis was the most frequently detected parasite, with a prevalence of 6.3%, followed by Taenia/Echinococcus spp. (2.9%), Isospora spp. (2.7%), and Toxascaris leonina (2.6%). Helminthes and protozoa were significantly more prevalent in household dogs than in stray dogs (Pparasites indicated that people residing in this area are at risk of exposure to these potentially hazardous zoonotic pathogens. Mass education of the general population is highly recommended to increase awareness of the potential for horizontal transmission of these parasitic infections from dogs to humans.
Light-driven dinitrogen reduction catalyzed by a CdS:nitrogenase MoFe protein biohybrid.

Science.gov (United States)

Brown, Katherine A; Harris, Derek F; Wilker, Molly B; Rasmussen, Andrew; Khadka, Nimesh; Hamby, Hayden; Keable, Stephen; Dukovic, Gordana; Peters, John W; Seefeldt, Lance C; King, Paul W

2016-04-22

The splitting of dinitrogen (N2) and reduction to ammonia (NH3) is a kinetically complex and energetically challenging multistep reaction. In the Haber-Bosch process, N2 reduction is accomplished at high temperature and pressure, whereas N2 fixation by the enzyme nitrogenase occurs under ambient conditions using chemical energy from adenosine 5'-triphosphate (ATP) hydrolysis. We show that cadmium sulfide (CdS) nanocrystals can be used to photosensitize the nitrogenase molybdenum-iron (MoFe) protein, where light harvesting replaces ATP hydrolysis to drive the enzymatic reduction of N2 into NH3 The turnover rate was 75 per minute, 63% of the ATP-coupled reaction rate for the nitrogenase complex under optimal conditions. Inhibitors of nitrogenase (i.e., acetylene, carbon monoxide, and dihydrogen) suppressed N2 reduction. The CdS:MoFe protein biohybrids provide a photochemical model for achieving light-driven N2 reduction to NH3. Copyright © 2016, American Association for the Advancement of Science.
Generation of strong inhomogeneous stray fields by high-anisotropy permanent magnets

Energy Technology Data Exchange (ETDEWEB)

Samofalov, V.N. [National Technical University Kharkov Polytechnical Institute, 21 Frunze St., 61002 Kharkov (Ukraine)]. E-mail: samofalov@kpi.kharkov.ua; Ravlik, A.G. [National Technical University Kharkov Polytechnical Institute, 21 Frunze St., 61002 Kharkov (Ukraine); Belozorov, D.P. [National Scientific Center Kharkov Institute of Physics and Techonology, NAS of Ukraine, 1 Akademicheskaja St., 61108 Kharkov (Ukraine); Avramenko, B.A. [National Technical University Kharkov Polytechnical Institute, 21 Frunze St., 61002 Kharkov (Ukraine)

2004-10-01

Magnetic stray fields for systems of permanent magnets with high magnetic anisotropy are calculated and measured. It is shown that intensity of these fields exceeds value of an induction of a material of magnets in some time. Besides, these fields are characterized by high gradients, and size H-bar H can reach values up to10{sup 10}-10{sup 11}Oe{sup 2}/cm. Estimations of extremely achievable fields and their gradients are made.
Stray-field-induced Faraday contributions in wide-field Kerr microscopy and -magnetometry

International Nuclear Information System (INIS)

Markó, D.; Soldatov, I.; Tekielak, M.; Schäfer, R.

2015-01-01

The magnetic domain contrast in wide-field Kerr microscopy on bulk specimens can be substantially distorted by non-linear, field-dependent Faraday rotations in the objective lens that are caused by stray-field components emerging from the specimen. These Faraday contributions, which were detected by Kerr-magnetometry on grain-oriented iron–silicon steel samples, are thoroughly elaborated and characterized. They express themselves as a field-dependent gray-scale offset to the domain contrast and in highly distorted surface magnetization curves if optically measured in a wide field Kerr microscope. An experimental method to avoid such distortions is suggested. In the course of these studies, a low-permeability part in the surface magnetization loop of slightly misoriented (110)-surfaces in iron–silicon sheets was discovered that is attributed to demagnetization effects in direction perpendicular to the sheet surface. - Highlights: • Magnetizing a finite sample in a Kerr microscope leads to sample-generated stray-fields. • They cause non-linear, field- and position-dependent Faraday rotations in the objective. • This leads to a modulation of the Kerr contrast and to distorted MOKE loops. • A method to compensate these Faraday rotations is presented
Reduction of a Ship's Magnetic Field Signatures

CERN Document Server

Holmes, John

2008-01-01

Decreasing the magnetic field signature of a naval vessel will reduce its susceptibility to detonating naval influence mines and the probability of a submarine being detected by underwater barriers and maritime patrol aircraft. Both passive and active techniques for reducing the magnetic signatures produced by a vessel's ferromagnetism, roll-induced eddy currents, corrosion-related sources, and stray fields are presented. Mathematical models of simple hull shapes are used to predict the levels of signature reduction that might be achieved through the use of alternate construction materials. Al
Investigations of prevalence of antibodies to B.canis in stray dogs in territory of Belgrade

Directory of Open Access Journals (Sweden)

Radojičić Sonja

2006-01-01

Full Text Available The paper covers investigations of stray dogs in the territory of the city of Belgrade. A total of 184 blood serum samples were examined for the presence of antibodies specific to Brucella canis. The method of slow agglutination in a test tube with 2- mercaptoethanol was used in the diagnostic procedure. Of the 184 examined serums, 49 (26.63% had a titer of 1/50, 25 serums had a titer of 1/100 (13.58%, while 20 serums had a titer equal to or bigger than 1/200 (10.87%. Furthermore, 15 samples of full blood from serologiclly negative animals were also presented for isolation. The bacteriological finding for these samples was negative. The obtained results indicate that the number of seropositive stray dogs in the territory of Belgrade is extremely high and that 10.87% of the testes animals are definitely infected with Brucella canis.
Helminth Infections of Stray Dogs from Garmsar, Semnan Province, Central Iran

Science.gov (United States)

Eslami, A; Ranjbar-Bahadori, Sh; Meshgi, B; Dehghan, M; Bokaie, S

2010-01-01

Background The aim was to study the gastro-intestinal helminths of stray dogs of Garmsar, Semnan Province, Central Iran, and its impacts on human health and animal production. Methods During 2006, the alimentary tracts of 50 stray dogs at necropsy, selected from villages around Garmsar, were removed, and examined for helminth infections. Subsequently helminths were collected from the contents of each part and scraped sample of small intestines of washed materials in a 100-mesh sieve. To identify the species of helminths, the nematodes were cleared in lactophenol and cestodes were stained using carmine acid. Results Mixed infection was the rule and 40 dogs (80%) harbored more than one species of helminth. Taenia hydatigena was the most prevalent species (80%) followed by Echinococcus granulosus (64%), Toxocara canis (22%), Mesocestoides lineatus (12%), Taenia multiceps (10%) and Dipylidium caninum (4%). The mean intensity of worm infection was low (1–3) except for that of E. granulosus (645). No significant difference was noticed between sex, age and most helminth infections except for that of sex and T. hydatigena (P=0.001) as well as age and T. canis (P=0.001). Conclusion Although human infection with T. hydatigena is unlikely, but other helminths reported in this study are of zoonotic importance, and may pose a threat to community health, and reduce the productions of ruminants harboring taeniid metacestodes. PMID:22347264
Rhodobacter capsulatus gains a competitive advantage from respiratory nitrate reduction during light-dark transitions.

Science.gov (United States)

Ellington, M J K; Richardson, D J; Ferguson, S J

2003-04-01

Rhodobacter capsulatus N22DNAR(+) possesses a periplasmic nitrate reductase and is capable of reducing nitrate to nitrite under anaerobic conditions. In the absence of light this ability cannot support chemoheterotrophic growth in batch cultures. This study investigated the effect of nitrate reduction on the growth of R. capsulatus N22DNAR(+) during multiple light-dark cycles of anaerobic photoheterotrophic/dark chemoheterotrophic growth conditions in carbon-limited continuous cultures. The reduction of nitrate did not affect the photoheterotrophic growth yield of R. capsulatus N22DNAR(+). After a transition from photoheterotrophic to dark chemoheterotrophic growth conditions, the reduction of nitrate slowed the initial washout of a R. capsulatus N22DNAR(+) culture. Towards the end of a period of darkness nitrate-reducing cultures maintained higher viable cell counts than non-nitrate-reducing cultures. During light-dark cycling of a mixed culture, the strain able to reduce nitrate (N22DNAR(+)) outcompeted the strain which was unable to reduce nitrate (N22). The evidence indicates that the periplasmic nitrate reductase activity supports slow growth that retards the washout of a culture during anaerobic chemoheterotrophic conditions, and provides a protonmotive force for cell maintenance during the dark period before reillumination. This translates into a selective advantage during repeated light-dark cycles, such that in mixed culture N22DNAR(+) outcompetes N22. Exposure to light-dark cycles will be a common feature for R. capsulatus in its natural habitats, and this study shows that nitrate respiration may provide a selective advantage under such conditions.
A PARASITOLOGIC AND MOLECULAR SURVEY OF HEPATOZOON CANIS INFECTION IN STRAY DOGS IN NORTHEAST OF IRAN.

Science.gov (United States)

Barati, Ali; Razmi, Gholamreza

2018-05-15

Canine hepatozoonosis, caused by H. canis, is a tick-borne disease in domestic and wild dogs that is transmitted by ingestion of Rhipicephalus sanguineus ticks. The aim of the study was to detect H. canis in stray dogs in Iran using blood smear examination and molecular techniques. From October 2014 to September 2015, 150 EDTA blood samples were collected from stray dogs in the northeast region of Iran. Blood smears were microscopically examined for the presence of Hepatozoon gamonts; whole blood was evaluated by PCR, with subsequent sequencing and phylogenetic analysis. Hepatozoon spp. Gamonts were observed in the neutrophils of 5/150 (3.3%) blood smears, whereas Hepatozoon spp. 18S rDNA was detected in 12/150 (8.0%) blood samples from stray dogs. There was a good agreement between microscopy and PCR methods. (Kappa= 0.756). The highest rate of infection was seasonally detected in the summer (pHepatozoon spp infection was not significant by gender and age factors (p>0.05). The alignment analysis of the sequenced samples showed ≥99% similarity with other nucleotide sequences of Hepatozoon spp. in GenBank. The phylogenetic tree also revealed that the nucleotide sequences in this study were clustered in the H. canis clade and different from the H. felis and H. americanum clades. According to the results, it is concluded that H. canis infection is present among dogs in northeastern region of Iran.
Gastrointestinal Helminthic Parasites in Stray Cats (Felis catus from North of Iran

Directory of Open Access Journals (Sweden)

A Rezaei-Doust

2007-08-01

Full Text Available Background: Cats play a crucial role in the epidemiology of gastrointestinal helminthic parasites and also play a major role in transmitting of these parasites through faecal contamination of soil, food or water. The aim of this study was to determine the species of gastrointestinal helminthes parasites in stray cats from a rural area of Bandar-e-Anzali, Iran.Method: Gastrointestinal helminthes were collected from 50 necropsied stray cats (Felis catus after capturing them by trapping from different regions of the city and humanely euthanatized in Bandar-e-Anzali, a port in the Caspian Sea in northern Iran, from March to November 2003. Results: The prevalence of infection was 90%, with those of individual parasites being Diplopylidium nolleri 54%, Physaloptera praeputialis 32%, Ancylostoma tubaeforme 20%, Joyeuxiella pasqualei 10%, Toxocara cati 8%, Pterygodermatites affinis 6%, Ancylostoma caninum 4%, and Taenia taeniaeformis 2%. Concurrent infections with two or more parasites were recorded in 34% of the individuals. In relation to the sex, the differences were not significant. Conclusion: P. praeputialis, T. cati, D. nolleri and sometime J. pasqualei are the commonest Helminthes in cats. This is the first reported isolation of P. affinis and A. caninum infections from cats in Iran.
Comment on "Density functional theory is straying from the path toward the exact functional"

DEFF Research Database (Denmark)

Kepp, Kasper Planeta

2017-01-01

Medvedev et al (Reports, 6 January 2017, p. 49) argue that recent density functionals stray from the path toward exactness. This conclusion rests on very compact 1s2 and 1s22s2 systems favored by the Hartree-Fock picture. Comparison to actual energies for the same systems indicates that the "stra...
The origin of the coercivity reduction of Nd–Fe–B sintered magnet annealed below an optimal temperature

International Nuclear Information System (INIS)

Akiya, T.; Sasaki, T.T.; Ohkubo, T.; Une, Y.; Sagawa, M.; Kato, H.; Hono, K.

2013-01-01

In order to understand the origin of the coercivity reduction in a sintered Nd–Fe–B magnet that is annealed below an optimal annealing temperature, we performed focused ion beam/scanning electron microscopy tomography of post-sinter annealed magnets. A number of grain boundary cracks were observed between Nd 2 Fe 14 B grains and Nd-rich phases in the sample annealed below the optimal temperature. We deduced micromagnetic parameters α and N eff by fitting the temperature dependence of the coercivity. While α was constant regardless of the annealing conditions, N eff increased in the sample annealed below the optimal temperature with the reduced coercivity. This indicates that the reduction of the coercivity is due to the local stray field at the cracks. - Highlights: • We performed FIB/SEM tomography of post-sinter annealed magnets. • A number of grain boundary cracks were observed in the low-coercivity sample. • Parameters α and N eff were deduced from the temperature dependence of coercivity. • While α was constant, N eff increased in the low-coercivity sample. • The reduction of the coercivity is due to the local stray field at the cracks
Performance analysis of photocatalytic CO2 reduction in optical fiber monolith reactor with multiple inverse lights

International Nuclear Information System (INIS)

Yuan, Kai; Yang, Lijun; Du, Xiaoze; Yang, Yongping

2014-01-01

Highlights: • A new optical fiber monolith reactor model for CO 2 reduction was developed. • Methanol concentration versus fiber location and operation parameters was obtained. • Reaction efficiency increases by 31.1% due to the four fibers and inverse layout. • With increasing space of fiber and channel center, methanol concentration increases. • Methanol concentration increases as the vapor ratio and light intensity increase. - Abstract: Photocatalytic CO 2 reduction seems potential to mitigate greenhouse gas emissions and produce renewable energy. A new model of photocatalytic CO 2 reduction in optical fiber monolith reactor with multiple inverse lights was developed in this study to improve the conversion of CO 2 to CH 3 OH. The new light distribution equation was derived, by which the light distribution was modeled and analyzed. The variations of CH 3 OH concentration with the fiber location and operation parameters were obtained by means of numerical simulation. The results show that the outlet CH 3 OH concentration is 31.1% higher than the previous model, which is attributed to the four fibers and inverse layout. With the increase of the distance between the fiber and the monolith center, the average CH 3 OH concentration increases. The average CH 3 OH concentration also rises as the light input and water vapor percentage increase, but declines with increasing the inlet velocity. The maximum conversion rate and quantum efficiency in the model are 0.235 μmol g −1 h −1 and 0.0177% respectively, both higher than previous internally illuminated monolith reactor (0.16 μmol g −1 h −1 and 0.012%). The optical fiber monolith reactor layout with multiple inverse lights is recommended in the design of photocatalytic reactor of CO 2 reduction

Barged/In-river steelhead migrant data - Evaluation of methods to reduce straying rates of barged juvenile steelhead

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The goals of this study are to develop methods to reduce wandering and straying of steelhead (Oncorhynchus mykiss) that are collected and barged from the Snake River...
Laboratory data on Snake River steelhead - Evaluation of methods to reduce straying rates of barged juvenile steelhead

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The goals of this study are to develop methods to reduce wandering and straying of steelhead (Oncorhynchus mykiss) that are collected and barged from the Snake River...
A survey study on gastrointestinal parasites of stray cats in northern region of Nile delta, Egypt.

Directory of Open Access Journals (Sweden)

Reda E Khalafalla

Full Text Available A survey study on gastrointestinal parasites in 113 faecal samples from stray cats collected randomly from Kafrelsheikh province, northern region of Nile delta of Egypt; was conducted in the period between January and May 2010. The overall prevalence was 91%. The results of this study reported seven helminth species: Toxocara cati (9%, Ancylostoma tubaeforme (4%, Toxascaris leonina (5%, Dipylidium caninum (5%, Capillaria spp. (3%, Taenia taeniformis (22% and Heterophyes heterophyes (3%, four protozoal species: Toxoplasma gondii (9%, Sarcocyst spp. (1%, Isospora spp. (2% and Giardia spp. (2% and two arthropod species; Linguatula serrata (2% and mites eggs (13%. The overall prevalence of intestinal parasites may continue to rise due to lack of functional veterinary clinics for cat care in Egypt. Therefore, there is a need to plan adequate control programs to diagnose, treat and control gastrointestinal parasites of companion as well as stray cats in the region.
A Survey Study on Gastrointestinal Parasites of Stray Cats in Northern Region of Nile Delta, Egypt

Science.gov (United States)

Khalafalla, Reda E.

2011-01-01

A survey study on gastrointestinal parasites in 113 faecal samples from stray cats collected randomly from Kafrelsheikh province, northern region of Nile delta of Egypt; was conducted in the period between January and May 2010. The overall prevalence was 91%. The results of this study reported seven helminth species: Toxocara cati (9%), Ancylostoma tubaeforme (4%), Toxascaris leonina (5%), Dipylidium caninum (5%), Capillaria spp. (3%), Taenia taeniformis (22%) and Heterophyes heterophyes (3%), four protozoal species: Toxoplasma gondii (9%), Sarcocyst spp. (1%), Isospora spp. (2%) and Giardia spp. (2%) and two arthropod species; Linguatula serrata (2%) and mites eggs (13%). The overall prevalence of intestinal parasites may continue to rise due to lack of functional veterinary clinics for cat care in Egypt. Therefore, there is a need to plan adequate control programs to diagnose, treat and control gastrointestinal parasites of companion as well as stray cats in the region. PMID:21760884
Helminth Infections of Stray Dogs from Garmsar, Semnan Province, Central Iran

Directory of Open Access Journals (Sweden)

A Eslami

2010-12-01

Full Text Available Background: The aim was to study the gastro-intestinal helminths of stray dogs of Garmsar, Semnan Province, Central Iran, and its impacts on human health and animal production.Methods: During 2006, the alimentary tracts of 50 stray dogs at necropsy, selected from villages around Garmsar, were removed, and examined for helminth infections. Subsequently helminths were collected from the contents of each part and scraped sample of small intestines of washed materials in a 100-mesh sieve. To identify the species of helminths, the nematodes were cleared in lactophenol and cestodes were stained using carmine acid.Results: Mixed infection was the rule and 40 dogs (80% harbored more than one species of helminth. Taenia hydatigena was the most prevalent species (80% followed by Echinococcus granulosus (64%, Toxocara canis (22%, Mesocestoides lineatus (12%, Taenia multiceps (10% and Dipylidium caninum (4%. The mean intensity of worm infection was low (1-3 except for that of E. granulosus (645. No significant difference was noticed between sex, age and most helminth infections except for that of sex and T. hydatigena (P=0.001 as well as age and T. canis (P=0.001.Conclusion: Although human infection with T. hydatigena is unlikely, but other helminths reported in this study are of zoonotic importance, and may pose a threat to community health, and reduce the productions of ruminants harboring taeniid metacestodes.
Thomson scattering in a low-pressure argon mercury positive column

NARCIS (Netherlands)

Bakker, L.P.; Kroesen, G.M.W.

2000-01-01

The electron density and the electron temperature in a low-pressure argon mercury positive column are determined using Thomson scattering. Special attention has been given to the stray light reduction in the Thomson scattering setup. The results are obtained in a discharge tube with a 26 mm diam, 5
Thomson scattering in a low-pressure neon mercury positive column

NARCIS (Netherlands)

Bakker, L.P.; Kroesen, G.M.W.

2001-01-01

The electron density and the electron temperature in a low-pressure neon mercury positive column are determined using Thomson scattering. Special attention has been given to the stray light reduction in the Thomson scattering setup. The results are obtained in a discharge tube with a 26 mm diam, 10
A Preliminary Study on the Helminth Fauna in Necropsied Stray Cats (Felis catus in Beni-Suef, Egypt

Directory of Open Access Journals (Sweden)

Khaled Mohamed El-Dakhly

2017-10-01

Full Text Available Stray cats play a crucial role in the epidemiology of endoparasites, particularly helminths, due to predating a wide range of both vertebrate and invertebrate hosts, often of veterinary and zoonotic importance. Therefore, a total of 62 stray cats were necropsied in Beni-Suef province, Egypt and examined for helminth parasites. The overall prevalence of infection was 87.0%. The recovered helminths consisted of 10 species of trematodes (Heterophyes heterophyes, Pygidiopsis summa, H. nocens, Echinochasmus liliputanus, Alaria sp., Procerovum varium, Ascocotyle sp., Haplorchis sp., Prohemistomum vivax, Euparadistomum herpestesi, five cestodes (Dipylidium caninum, Diplopylidium acanthoterta, D. nolleri, Joyeuxiella sp. and Taenia taeniaeformis, and two nematodes (Toxascaris leonina and larvae of Anisakis simplex. The most prevalent helminths were Dipylidium caninum (62.9%, Toxascaris leonina (33.8%, Diplopylidium nolleri (22.5% and Echinochasmus liliputanus (6.45%. Thirty (48.39% cats were co-infected by one species, 22 (35.48% by two and three (4.84% by more than two species. It has been found that cats aged more than 3 years were the most infected. Both male and female cats were parasitized. The infection was the most prevalent in both summer and autumn. In conclusion, veterinarians must highlight more attention towards both stray and domestic cats, as they are considered reservoir hosts for a wide host range of parasites, particularly helminths, and the zoonotic importance of such parasites should be taken on consideration.
Possibility of reducing stray losses and parasitic torques in two-phase emergency feeding of induction motors

Czech Academy of Sciences Publication Activity Database

Schreier, Luděk; Bendl, Jiří; Chomát, Miroslav; Klíma, J.

2006-01-01

Roč. 51, č. 2 (2006), s. 109-131 ISSN 0001-7043 R&D Projects: GA ČR(CZ) GA102/04/0215 Institutional research plan: CEZ:AV0Z20570509 Keywords : induction motor * emergency operation of electrical drives * stray losses Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering
Magnetic charge distribution and stray field landscape of asymmetric néel walls in a magnetically patterned exchange bias layer system

Science.gov (United States)

Zingsem, Norbert; Ahrend, Florian; Vock, Silvia; Gottlob, Daniel; Krug, Ingo; Doganay, Hatice; Holzinger, Dennis; Neu, Volker; Ehresmann, Arno

2017-12-01

The 3D stray field landscape above an exchange bias layer system with engineered domain walls has been fully characterized by quantitative magnetic force microscopy (qMFM) measurements. This method is based on a complete quantification of the MFM tip’s imaging properties and the subtraction of its contribution from the measured MFM data by deconvolution in Fourier space. The magnetically patterned Ir17Mn83/Co70Fe30-exchange-bias-multilayers have been designed to contain asymmetric head-to-head (hh)/tail-to-tail (tt) Néel walls between domains of different magnetic anisotropies for potential use in guided particle transport. In the current application, qMFM reveals the effective magnetic charge profile on the surface of the sample—with high spatial resolution and in an absolute quantitative manner. These data enable to calculate the magnetostatic potential and the full stray field landscape above the sample surface. It has been successfully tested against: (i) micromagnetic simulations of the magnetization structure of a comparable exchange-bias layer system, (ii) measurements of the magnetization profile across the domain boundary with x-ray photoemission electron microscopy, and (iii) direct stray field measurements obtained by scanning Hall probe microscopy at elevated scan heights. This approach results in a quantitative determination of the stray field landscape at close distances to the sample surface, which will be of importance for remote magnetic particle transport applications in lab-on-a-chip devices. Furthermore, the highly resolving and quantitative MFM approach reveals details of the domain transition across the artificially structured phase boundary, which have to be attributed to a continuous change in the materials parameters across this boundary, rather than an abrupt one.
3D Printing of Polymer-Bonded Rare-Earth Magnets With a Variable Magnetic Compound Fraction for a Predefined Stray Field.

Science.gov (United States)

Huber, Christian; Abert, Claas; Bruckner, Florian; Groenefeld, Martin; Schuschnigg, Stephan; Teliban, Iulian; Vogler, Christoph; Wautischer, Gregor; Windl, Roman; Suess, Dieter

2017-08-25

Additive manufacturing of polymer-bonded magnets is a recently developed technique, for single-unit production, and for structures that have been impossible to manufacture previously. Also, new possibilities to create a specific stray field around the magnet are triggered. The current work presents a method to 3D print polymer-bonded magnets with a variable magnetic compound fraction distribution. This means the saturation magnetization can be adjusted during the printing process to obtain a required external field of the manufactured magnets. A low-cost, end-user 3D printer with a mixing extruder is used to mix permanent magnetic filaments with pure polyamide (PA12) filaments. The magnetic filaments are compounded, extruded, and characterized for the printing process. To deduce the quality of the manufactured magnets with a variable magnetic compound fraction, an inverse stray field framework is developed. The effectiveness of the printing process and the simulation method is shown. It can also be used to manufacture magnets that produce a predefined stray field in a given region. This opens new possibilities for magnetic sensor applications. This setup and simulation framework allows the design and manufacturing of polymer-bonded permanent magnets, which are impossible to create with conventional methods.
Toxocara nematodes in stray cats from shiraz, southern iran: intensity of infection and molecular identification of the isolates.

Directory of Open Access Journals (Sweden)

Fattaneh Mikaeili

2013-12-01

Full Text Available Toxocara is a common nematode of cats in different parts of Iran. Despite the close association of cats with human, no attempt has been done so far for molecular identification of this nematode in the country. Therefore, current study was performed on identification of some isolates of Toxocara from stray cats in Shiraz, Fars Province, Southern Iran, based on morphological and molecular approaches, and also determination of intensity of infection.This cross-sectional study was carried out on 30 stray cats trapped from different geographical areas of Shiraz in 2011. Adult male and female worms were recovered from digestive tract after dissection of cats. Morphological features using existing keys and PCR-sequencing of ITS-rDNA region and pcox1 mitochondrial l gene were applied for the delineating the species of the parasites.Eight out of 30 cats (26.7% were found infected with Toxocara nematodes. All the isolates were confirmed as Toxocara cati based on morphological features and the sequence of ribosomal and mitochondrial targets. Intensity of infection ranged from one to a maximum of 39 worms per cat, with a mean of 10.25±12.36, and higher abundance of female nematodes.The most prevalent ascaridoid nematode of stray cats in the study area was T. cati and female nematodes were more abundant than that of males. This issue has important role in spreading of eggs in the environment and impact on human toxocariasis.
Measurement of stray neutron doses inside the treatment room from a proton pencil beam scanning system

Czech Academy of Sciences Publication Activity Database

Mojzeszek, N.; Farah, J.; Klodowska, M.; Ploc, Ondřej; Stolarczyk, L.; Waligorski, M. P. R.; Olko, P.

2017-01-01

Roč. 34, č. 2 (2017), s. 80-84 ISSN 1120-1797 Institutional support: RVO:61389005 Keywords : secondary neutrons * proton therapy * pencil beam scanning systtems * out-of-field doses * stray neutron doses * TEPC Subject RIV: FP - Other Medical Disciplines OBOR OECD: Radiology, nuclear medicine and medical imaging Impact factor: 1.990, year: 2016
Low frequency noise reduction using stiff light composite panels

Institute of Scientific and Technical Information of China (English)

DENG Yongchang; LIN Weizheng

2003-01-01

The experiment presented in this paper is to investigate and analyze the noise reduction at low frequency using stiff light composite panels. Since these composite panels are made of lightweight and stiff materials, this actuation strategy will enable the creation of composite panels for duct noise control without using traditional heavy structural mass. The results suggest that the mass-spring resonance absorption in the case of a comparatively stiff thick panel with a thin flexible plate is more efficient with minimum weight, when subjected to low-frequency (<500 Hz). The efficiency of the panel absorber depends on the mass of the thin flexible plate and the stiffness of the panel.
Humoral immune response to Dipylidium caninum infection of stray dogs in Taiwan.

Science.gov (United States)

Shin, J W; Liao, W T

2002-04-02

Two kinds of homogeneous proglottid, mature and gravid, of Dipylidium caninum were used as the antigens for immunodiagnosis of canine dipylidiosis in stray dogs in Tainan, Taiwan. The ELISA was performed on 30 serum samples; 24 from dipylidiosis, four from ancylostomosis and two from toxocariosis. The ELISA have specificity and sensitive of 100 and 50% for mature proglottid extract, and 75 and 100%, respectively, for gravid proglottid extract. EITB technique showed two major peptide bands of 94.8 and 97.9kDa were recognized in the sera pool of infected dogs.
Induced radioactivity of materials by stray radiation fields at an electron accelerator

CERN Document Server

Rokni, S H; Gwise, T; Liu, J C; Roesler, S

2002-01-01

Samples of soil, water, aluminum, copper and iron were irradiated in the stray radiation field generated by the interaction of a 28.5 GeV electron beam in a copper-dump in the Beam Dump East facility at the Stanford Linear Accelerator Center. The specific activity induced in the samples was measured by gamma spectroscopy and other techniques. In addition, the isotope production in the samples was calculated with detailed Monte Carlo simulations using the FLUKA code. The calculated activities are compared to the experimental values and differences are discussed.
Factors affecting the prevalence of mange-mite infestations in stray dogs of Yucatán, Mexico.

Science.gov (United States)

Rodriguez-Vivas, R I; Ortega-Pacheco, A; Rosado-Aguilar, J A; Bolio, G M E

2003-07-10

The aim of the present study was to determine the factors affecting the prevalence of mange-mite infestations in stray dogs of Yucatán, Mexico. The study was carried out in 200 stray dogs of Mérida capital city of Yucatán, Mexico. Four samples (head, thoracic-abdominal area, extremities and ear) were taken from each animal by skin scraping and examined microscopically in 10% KOH solution to detect the presence of mites. Mites were also collected from the external ear canal of dogs using cotton-tipped swabs. The prevalence of different mite species was calculated. A primary screening was performed using 2xK contingency tables of exposure variables. All variables with PDemodex canis (23.0%) was the most frequent mite, followed by Sarcoptes scabei var. canis (7.0%) and Otodectes cynotis (3.5%). The following factors were found: body condition (bad, OR: 5.35, CI 95%: 1.66-17.3; regular, OR: 3.72, CI 95%: 1.39-9.99) and the presence of macroscopic lesions of dermatosis (OR: 42.80, CI 95%: 13.65-134.24).
Antibody Detection to Feline Immunodeficiency virus (FIV in stray cats in Ahvaz, southwestern Iran

Directory of Open Access Journals (Sweden)

Mosallanejad, B.

2010-01-01

Full Text Available The present study was performed to determine the prevalence of FIV in stray cat's population of Ahvaz different area. Serum samples were collected from 90 cats from 2005 to 2007. The studied cats were divided into two age groups (3 years and based on clinical signs (such as lymphadenopathy, periodontal diseases, gingivitis, abscess and cashecsi into two groups also. The results were analyzed using Fischer's exact test and Chi-square analysis. Prevalence to FIV antibodies in these cats was 15.55% (14 of 90 by means of ELISA Test Kit, indicating that this virus is present in the ecosystem. The infection had more prevalence in cats above 3 years (78.6%; 11 of 14 compared with cats less than 3 years (21.4%; 3 of 14. Statistical analysis showed significant difference between different age groups (P0.05. Three out of 12 cases (25% which had clinical signs and 11 out of 78 cases (14.1% which hadn’t clinical signs were seropositive. There was no significant difference between the two groups also (P>0.05. This study showed that FIV exist among cat's population of Ahvaz area and separation of companion and stray cats is very important for prevention of disease transmission to companion cats.
Community perception regarding rabies prevention and stray dog control in urban slums in India.

Science.gov (United States)

Herbert, Mrudu; Riyaz Basha, S; Thangaraj, Selvi

2012-12-01

The lack of community awareness about rabies control is a major issue that thwarts efforts to prevent human deaths caused by rabies. The objectives of this study were (1) to assess community knowledge and attitudes about rabies, rabies prevention and stray dog control in an urban slum community and (2) to determine the factors that influence rabies awareness in urban slums. Using a systematic random sampling strategy, 185 participants were selected from 8 urban slums. The data were collected by direct interview using a pre-tested, structured questionnaire. In the study population, 74.1% of the participants had heard about rabies, and 54.1% knew that rabies is a fatal disease. Only 33.5% of the interviewees felt that people in the community had a role to play in controlling the stray dog population. Gender, age and educational status were significantly associated with rabies awareness. Our study indicates that there are gaps in the knowledge and attitudes of individuals living in urban slums regarding rabies prevention and control. Efforts to promote awareness should be targeted at men, older people and uneducated individuals. Copyright © 2012 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.
The effectiveness of riboflavin and ultraviolet light pathogen reduction technology in eliminating Trypanosoma cruzi from leukoreduced whole blood.

Science.gov (United States)

Jimenez-Marco, Teresa; Cancino-Faure, Beatriz; Girona-Llobera, Enrique; Alcover, M Magdalena; Riera, Cristina; Fisa, Roser

2017-06-01

The parasitic Chagas disease is caused by the protozoan Trypanosoma cruzi, which is mainly transmitted by insect vectors. Other infection routes, both in endemic and in nonendemic areas, include organ and marrow transplantation, congenital transmission, and blood transfusion. Asymptomatic chronic chagasic individuals may have a low and transient parasitemia in peripheral blood and, consequently, they can unknowingly transmit the disease via blood transfusion. Riboflavin and ultraviolet (UV) light pathogen reduction is a method to reduce pathogen transfusion transmission risk based on damage to the pathogen nucleic acids. In this study, we tested the effectiveness of this technology for the elimination of T. cruzi parasites in artificially contaminated whole blood units (WBUs) and thus for decreasing the risk of T. cruzi transfusion transmission. The contaminated WBUs were leukoreduced by filtration and treated with riboflavin and UV light. The level of pathogen reduction was quantified by a real-time polymerase chain reaction (qPCR) and a real-time reverse transcription-polymerase chain reaction (RT-qPCR) as a viability assay. The RNA (cDNA) quantification of the parasites showed a more than 99% reduction of viable T. cruzi parasites after leukoreduction and a complete reduction (100%) after the riboflavin and UV light treatment. Riboflavin and UV light treatment and leukoreduction used in conjunction appears to eliminate significant amounts of viable T. cruzi in whole blood. Both strategies could complement other blood bank measures already implemented to prevent the transmission of T. cruzi via blood transfusion. © 2017 AABB.

Robust sensor for turbidity measurement from light scattering and absorbing liquids.

Science.gov (United States)

Kontturi, Ville; Turunen, Petri; Uozumi, Jun; Peiponen, Kai-Erik

2009-12-01

Internationally standardized turbidity measurements for probing solid particles in liquid are problematic in the case of simultaneous light scattering and absorption. A method and a sensor to determine the turbidity in the presence of light absorption are presented. The developed sensor makes use of the total internal reflection of a laser beam at the liquid-prism interface, and the turbidity is assessed using the concept of laser speckle pattern. Using average filtering in speckle data analyzing the observed dynamic speckle pattern, which is due to light scattering from particles and the static speckle due to stray light of the sensor, can be separated from each other. Good correlation between the standard deviation of dynamic speckle and turbidity value for nonabsorbing and for absorbing liquids was observed. The sensor is suggested, for instance, for the measurement of ill-behaved as well as small-volume turbid liquids in both medicine and process industry.
Characteristics and performance of the Los Alamos VUV beamline at the NSLS

International Nuclear Information System (INIS)

Bartlett, R.J.; Trela, W.J.; Michaud, F.D.; Southworth, S.H.; Alkire, R.W.; Roy, P.; Rothe, R.; Walsh, P.J.; Shinn, N.

1988-01-01

We describe the design and performance of the Los Alamos VUV synchrotron radiation beamline, U3C, on the VUV ring of the National Synchrotron Light Source at Brookhaven National Laboratory. The beamline uses separate function optics to collect and focus the horizontally and vertically diverging beam. The monochromator is a grazing incidence Rowland circle instrument of the extended grasshopper design (ERG). A postmonochromator refocusing mirror is used to focus or collimate the diverging beam from the monochromator. The beamline control and diagnostics systems are also discussed. Particular emphasis in the design has been placed on the reduction of stray and harmonic light. Higher order light is reduced by a grazing angle mirror low pass filter installed immediately downstream from the monochromator while stray light is reduced through the use of baffles and thin film filters. Also included in the line is a differential pumping section that permits gas phase and other experiments requiring pressures in the 10 -5 to 10 -4 Torr range to be coupled to the beamline. (orig.)
An evaluation of safety guidelines to restrict exposure to stray radiofrequency radiation from short-wave diathermy units

Energy Technology Data Exchange (ETDEWEB)

Shields, Nora [School of Physiotherapy, La Trobe University, Victoria 3086 (Australia); O' Hare, Neil [Department of Medical Physics and Bioengineering, St James' s Hospital, Dublin 8 (Ireland); Gormley, John [School of Physiotherapy, Trinity College Dublin, Trinity Centre for Health Sciences, St James' s Hospital, Dublin 8 (Ireland)

2004-07-07

Short-wave diathermy (SWD), a form of radiofrequency radiation used therapeutically by physiotherapists, may be applied in continuous (CSWD) or pulsed (PSWD) mode using either capacitive or inductive methods. Stray radiation emitted by these units may exceed exposure guidelines close to the equipment. Discrepant guidelines exist on a safe distance from an operating unit for operators and other personnel. Stray electric (E-field) and magnetic (H-field) field strengths from 10 SWD units in six departments were examined using a PMM 8053 meter and two isotropic probes (EP-330, HP-032). A 5 l saline phantom completed the patient circuit. Measurements were recorded in eight directions between 0.5 m and 2 m at hip and eye levels while the units operated at maximum output and data compared to current guidelines. Results found stray fields from capacitive CSWD fell below operator limits at 2 m (E-field 4.8-39.8 V/m; H-field 0.015-0.072 A/m) and at 1 m for inductive CSWD (E-field 0-36 V/m; H-field 0.01-0.065 A/m). Capacitive PSWD fields fell below the limits at 1.5 m (E-field 1.2-19.9 V/m; H-field 0.002-0.045 A/m) and at 1m for inductive PSWD (E-field 0.7-4.0 V/m; H-field 0.009-0.03 A/m). An extra 0.5 m was required before fields fell below the guidelines for other personnel. These results demonstrate, under a worst case scenario, emissions from SWD exceed the guidelines for operators at distances currently recommended as safe. Future guidelines should include recommendations for personnel other than physiotherapists.
An evaluation of safety guidelines to restrict exposure to stray radiofrequency radiation from short-wave diathermy units

International Nuclear Information System (INIS)

Shields, Nora; O'Hare, Neil; Gormley, John

2004-01-01

Short-wave diathermy (SWD), a form of radiofrequency radiation used therapeutically by physiotherapists, may be applied in continuous (CSWD) or pulsed (PSWD) mode using either capacitive or inductive methods. Stray radiation emitted by these units may exceed exposure guidelines close to the equipment. Discrepant guidelines exist on a safe distance from an operating unit for operators and other personnel. Stray electric (E-field) and magnetic (H-field) field strengths from 10 SWD units in six departments were examined using a PMM 8053 meter and two isotropic probes (EP-330, HP-032). A 5 l saline phantom completed the patient circuit. Measurements were recorded in eight directions between 0.5 m and 2 m at hip and eye levels while the units operated at maximum output and data compared to current guidelines. Results found stray fields from capacitive CSWD fell below operator limits at 2 m (E-field 4.8-39.8 V/m; H-field 0.015-0.072 A/m) and at 1 m for inductive CSWD (E-field 0-36 V/m; H-field 0.01-0.065 A/m). Capacitive PSWD fields fell below the limits at 1.5 m (E-field 1.2-19.9 V/m; H-field 0.002-0.045 A/m) and at 1m for inductive PSWD (E-field 0.7-4.0 V/m; H-field 0.009-0.03 A/m). An extra 0.5 m was required before fields fell below the guidelines for other personnel. These results demonstrate, under a worst case scenario, emissions from SWD exceed the guidelines for operators at distances currently recommended as safe. Future guidelines should include recommendations for personnel other than physiotherapists
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.
A survey of ectoparasite infestations in stray dogs of Gwang-ju City, Republic of Korea.

Science.gov (United States)

Chee, Jeong Hyun; Kwon, Jung Kee; Cho, Ho Seong; Cho, Kyoung Oh; Lee, Yu Jin; Abd El-Aty, A M; Abdel-Aty, A M; Shin, Sung Shik

2008-03-01

This study was designed to investigate the incidence of ectoparasite infestation among stray dogs in Gwang-ju City, Republic of Korea. A total of 103 stray dogs collected in the Animal Shelter of Gwang-ju City from November 2003 to August 2005 were investigated in this study. Ectoparasites of one or more genera were detected in 45.6% (47 / 103) of the dogs examined for dermatologic lesions and/or skin scrapings (from 3-5 affected areas). Otodectes cynotis was found to be the most frequent parasite (22.3%, 23 / 103), followed by Sarcoptes scabiei var canis (19.4%, 20 / 103), Ctenocephalides canis (6.8%, 7 / 103), Demodex canis (4.9%, 5 / 103), and Trichodectes canis (1.0%, 1 / 103). Monospecific infestation was found in 83.0% (39 / 47) of the affected dogs, whereas concurrent infestations with 2 or more ectoparasites per animal were found in 17.0% (8 / 47) of the affected dogs. Trichodectes canis is reported for the first time in the Republic of Korea. Dogs less than 1 yr old were more heavily infected than other age groups (66.7%), and small-sized dogs of less than 3 kg body weight were more heavily infected than larger dogs (41.7%).
Casting light on harm reduction

DEFF Research Database (Denmark)

Jourdan, Michael

2009-01-01

Background: Harm reduction is commonly regarded as complementary to other drug problem responses - as the fourth tier. Yet even core examples of harm reduction such as the provision of injection equipment and methadone treatment has over and over encountered considerable opposition, and harm redu...
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.
Measurement of stray radiation within a scanning proton therapy facility: EURADOS WG9 intercomparison exercise of active dosimetry systems

Czech Academy of Sciences Publication Activity Database

Farah, J.; Mares, V.; Romero-Exposito, M.; Trinkl, S.; Domingo, C.; Dufek, V.; Klodowska, M.; Kubančák, Ján; Knezevic, Z.; Ploc, Ondřej

2015-01-01

Roč. 42, č. 5 (2015), s. 2572-2584 ISSN 0094-2405 Institutional support: RVO:61389005 Keywords : scanning proton therapy * measurement of stray neutrons * spectrometry * ambient dose eyuivalent * intercomparison Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 2.496, year: 2015
Endogenous NO3- in the root as a source of substrate for reduction in the light

International Nuclear Information System (INIS)

Rufty, T.W. Jr.; Volk, R.J.; MacKown, C.T.

1987-01-01

An experiment was conducted to investigate the reduction of endogenous NO 3 - , which had been taken up by plants in darkness, during the course of the subsequent light period. Vegetative, nonnodulated soybean plant (Glycine max [L.]. Merrill, Ransom) were exposed to 1.0 millimolar 15 NO 3 - for 12 hours in darkness and then returned to a solution containing 1.0 millimolar 14 NO 3 - for the 12 hours chase period in the light. Another set of plants was exposed to 15 NO 3 - during the light period to allow a direct comparison of contributions of substrate from the endogenous and exogenous sources. At the end of the 15 NO 3 - exposure in the dark, 70% of the absorbed 15 NO 3 - remained unreduced, and 83% of this unreduced NO 3 - was retained in roots. The pool of endogenous 15 NO 3 - in roots was depleted at a steady rate during the initial 9 hours of light and was utilized almost exclusively in the formation of insoluble reduced-N in leaves. Unlabeled endogenous NO 3 - , which had accumulated in the root prior to the previous dark period, also was depleted in the light. When exogenous 15 NO 3 - was supplied during the light period, the rate of assimilation progressively increased, reflecting an increased rate of uptake and decreased accumulation of NO 3 - in the root tissue. The dark-absorbed endogenous NO 3 - in the root was the primary source of substrate for whole-plant NO 3 - reduction in the first 6 hours of the light period, and exogenous NO 3 - was the primary source of substrate thereafter
Enhanced visible-light activities for PEC water reduction of CuO nanoplates by coupling with anatase TiO2 and mechanism

International Nuclear Information System (INIS)

Li, Zhijun; Qu, Yang; He, Guangwen; Humayun, Muhammad; Chen, Shuangying; Jing, Liqiang

2015-01-01

Graphical abstract: - Highlights: • CuO nanoplates were successfully prepared as photocathodes for PEC water reduction. • Visible-light activity for PEC water reduction is improved after coupling with TiO 2 . • Improved PEC performance is attributed to the enhanced visible-excited charge separation. • Enhanced charge separation results from high-energy electron transfer from CuO to TiO 2 . - Abstract: CuO nanoplates were prepared by a feasible hydrothermal method, and then utilized as photocathodes for photoelectrochemical (PEC) water reduction in a neutral medium under visible-light irradiation. It is clearly demonstrated that the visible-light activities of the resulting nanoplates for PEC water reduction could be greatly improved after coupling with a proper amount of nanocrystalline anatase TiO 2 . This is attributed to the enhanced charge separation in the fabricated TiO 2 /CuO nanoplate composites mainly based on the atmosphere-controlled steady-state surface photovoltage spectra. Moreover, it is suggested that the enhanced charge separation resulted from the transfer of visible-light-excited high-energy electrons from CuO to TiO 2 as confirmed from the single-wavelength PEC behavior
Light-cone reduction vs. TsT transformations: a fluid dynamics perspective

Science.gov (United States)

Dutta, Suvankar; Krishna, Hare

2018-05-01

We compute constitutive relations for a charged (2+1) dimensional Schrödinger fluid up to first order in derivative expansion, using holographic techniques. Starting with a locally boosted, asymptotically AdS, 4 + 1 dimensional charged black brane geometry, we uplift that to ten dimensions and perform TsT transformations to obtain an effective five dimensional local black brane solution with asymptotically Schrödinger isometries. By suitably implementing the holographic techniques, we compute the constitutive relations for the effective fluid living on the boundary of this space-time and extract first order transport coefficients from these relations. Schrödinger fluid can also be obtained by reducing a charged relativistic conformal fluid over light-cone. It turns out that both the approaches result the same system at the end. Fluid obtained by light-cone reduction satisfies a restricted class of thermodynamics. Here, we see that the charged fluid obtained holographically also belongs to the same restricted class.
Laser and Light Treatments for Hair Reduction in Fitzpatrick Skin Types IV-VI: A Comprehensive Review of the Literature.

Science.gov (United States)

Fayne, Rachel A; Perper, Marina; Eber, Ariel E; Aldahan, Adam S; Nouri, Keyvan

2018-04-01

Unwanted facial and body hair presents as a common finding in many patients, such as females with hirsutism. With advances in laser and light technology, a clinically significant reduction in hair can be achieved in patients with light skin. However, in patients with darker skin, Fitzpatrick skin types (FST) IV-VI, the higher melanin content of the skin interferes with the proposed mechanism of laser-induced selective photothermolysis, which is to target the melanin in the hair follicle to cause permanent destruction of hair bulge stem cells. Many prospective and retrospective studies have been conducted with laser and light hair-removal devices, but most exclude patients with darkly pigmented skin, considering them a high-risk group for unwanted side effects, including pigmentation changes, blisters, and crust formation. We reviewed the published literature to obtain studies that focused on hair reduction for darker skin types. The existing literature for this patient population identifies longer wavelengths as a key element of the treatment protocol and indicates neodymium-doped yttrium aluminum garnet (Nd:YAG), diode, alexandrite, and ruby lasers as well as certain intense pulsed light sources for safe hair reduction with minimal side effects in patients with FST IV-VI, so long as energy settings and wavelengths are appropriate. Based on the findings in this review, safe and effective hair reduction for patients with FST IV-VI is achievable under proper treatment protocols and energy settings.
Long-term reduction in infrared autofluorescence caused by infrared light below the maximum permissible exposure.

Science.gov (United States)

Masella, Benjamin D; Williams, David R; Fischer, William S; Rossi, Ethan A; Hunter, Jennifer J

2014-05-20

Many retinal imaging instruments use infrared wavelengths to reduce the risk of light damage. However, we have discovered that exposure to infrared illumination causes a long-lasting reduction in infrared autofluorescence (IRAF). We have characterized the dependence of this effect on radiant exposure and investigated its origin. A scanning laser ophthalmoscope was used to obtain IRAF images from two macaques before and after exposure to 790-nm light (15-450 J/cm(2)). Exposures were performed with either raster-scanning or uniform illumination. Infrared autofluorescence images also were obtained in two humans exposed to 790-nm light in a separate study. Humans were assessed with direct ophthalmoscopy, Goldmann visual fields, multifocal ERG, and photopic microperimetry to determine whether these measures revealed any effects in the exposed locations. A significant decrease in IRAF after exposure to infrared light was seen in both monkeys and humans. In monkeys, the magnitude of this reduction increased with retinal radiant exposure. Partial recovery was seen at 1 month, with full recovery within 21 months. Consistent with a photochemical origin, IRAF decreases caused by either raster-scanning or uniform illumination were not significantly different. We were unable to detect any effect of the light exposure with any measure other than IRAF imaging. We cannot exclude the possibility that changes could be detected with more sensitive tests or longer follow-up. This long-lasting effect of infrared illumination in both humans and monkeys occurs at exposure levels four to five times below current safety limits. The photochemical basis for this phenomenon remains unknown. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.
Stray dogs as indicators of Toxoplasma gondii distributed in the environment: the first report across an urban-rural gradient in China

Directory of Open Access Journals (Sweden)

Yan Chao

2012-01-01

Full Text Available Abstract Background Toxoplasmosis is an important parasitic zoonosis caused by the protozoan Toxoplasma gondii that is distributed world-wide and infects a variety of hosts. However, the prevalence of T. gondii in the environment (such as soil, water and food is largely unknown. Due to the technical difficulty in oocyst counting directly, an alternative assay using the serologic status of T. gondii in free-living animals, such as stray or free-living dogs, as an indicator, can be used to evaluate environmental contamination indirectly, as they are exposed to the same risk of infection as humans and other animals. Results In the present study, 231 stray or free-living dogs across an urban-rural gradient were examined to assess the frequency of T. gondii in the environment. Specific antibodies to T. gondii were found in 93 dogs (40.3% by enzyme-linked immunosorbent assay (ELISA, and no statistically significant differences were observed in seroprevalences of T. gondii between urban dogs (38.7% and rural dogs (41% (p > 0.05. Conclusions A high seroprevalence of T. gondii in stray or free-living dogs in the present study indicates that there would be a wide distribution and a constant infection pressure of T. gondii across an urban-rural gradient, and the oocysts of T. gondii in the environment would be an important source of infection for humans and other animals both in urban and rural areas in China.
SU-E-T-598: Parametric Equation for Quick and Reliable Estimate of Stray Neutron Doses in Proton Therapy and Application for Intracranial Tumor Treatments

Energy Technology Data Exchange (ETDEWEB)

Bonfrate, A; Farah, J; Sayah, R; Clairand, I [Institut de Radioprotection et de Surete Nucleaire (IRSN), Fontenay-aux-roses (France); De Marzi, L; Delacroix, S [Institut Curie Centre de Protontherapie d Orsay (CPO), Orsay (France); Herault, J [Centre Antoine Lacassagne (CAL) Cyclotron biomedical, Nice (France); Lee, C [National Cancer Institute, Rockville, MD (United States); Bolch, W [Univ Florida, Gainesville, FL (United States)

2015-06-15

Purpose: Development of a parametric equation suitable for a daily use in routine clinic to provide estimates of stray neutron doses in proton therapy. Methods: Monte Carlo (MC) calculations using the UF-NCI 1-year-old phantom were exercised to determine the variation of stray neutron doses as a function of irradiation parameters while performing intracranial treatments. This was done by individually changing the proton beam energy, modulation width, collimator aperture and thickness, compensator thickness and the air gap size while their impact on neutron doses were put into a single equation. The variation of neutron doses with distance from the target volume was also included in it. Then, a first step consisted in establishing the fitting coefficients by using 221 learning data which were neutron absorbed doses obtained with MC simulations while a second step consisted in validating the final equation. Results: The variation of stray neutron doses with irradiation parameters were fitted with linear, polynomial, etc. model while a power-law model was used to fit the variation of stray neutron doses with the distance from the target volume. The parametric equation fitted well MC simulations while establishing fitting coefficients as the discrepancies on the estimate of neutron absorbed doses were within 10%. The discrepancy can reach ∼25% for the bladder, the farthest organ from the target volume. Finally, the validation showed results in compliance with MC calculations since the discrepancies were also within 10% for head-and-neck and thoracic organs while they can reach ∼25%, again for pelvic organs. Conclusion: The parametric equation presents promising results and will be validated for other target sites as well as other facilities to go towards a universal method.
Controlling trapping potentials and stray electric fields in a microfabricated ion trap through design and compensation

International Nuclear Information System (INIS)

Charles Doret, S; Amini, Jason M; Wright, Kenneth; Volin, Curtis; Killian, Tyler; Ozakin, Arkadas; Denison, Douglas; Hayden, Harley; Pai, C-S; Slusher, Richart E; Harter, Alexa W

2012-01-01

Recent advances in quantum information processing with trapped ions have demonstrated the need for new ion trap architectures capable of holding and manipulating chains of many (>10) ions. Here we present the design and detailed characterization of a new linear trap, microfabricated with scalable complementary metal-oxide-semiconductor (CMOS) techniques, that is well-suited to this challenge. Forty-four individually controlled dc electrodes provide the many degrees of freedom required to construct anharmonic potential wells, shuttle ions, merge and split ion chains, precisely tune secular mode frequencies, and adjust the orientation of trap axes. Microfabricated capacitors on dc electrodes suppress radio-frequency pickup and excess micromotion, while a top-level ground layer simplifies modeling of electric fields and protects trap structures underneath. A localized aperture in the substrate provides access to the trapping region from an oven below, permitting deterministic loading of particular isotopic/elemental sequences via species-selective photoionization. The shapes of the aperture and radio-frequency electrodes are optimized to minimize perturbation of the trapping pseudopotential. Laboratory experiments verify simulated potentials and characterize trapping lifetimes, stray electric fields, and ion heating rates, while measurement and cancellation of spatially-varying stray electric fields permits the formation of nearly-equally spaced ion chains. (paper)
Stray field signatures of Néel textured skyrmions in Ir/Fe/Co/Pt multilayer films

Science.gov (United States)

Yagil, A.; Almoalem, A.; Soumyanarayanan, Anjan; Tan, Anthony K. C.; Raju, M.; Panagopoulos, C.; Auslaender, O. M.

2018-05-01

Skyrmions are nanoscale spin configurations with topological properties that hold great promise for spintronic devices. Here, we establish their Néel texture, helicity, and size in Ir/Fe/Co/Pt multilayer films by constructing a multipole expansion to model their stray field signatures and applying it to magnetic force microscopy images. Furthermore, the demonstrated sensitivity to inhomogeneity in skyrmion properties, coupled with a unique capability to estimate the pinning force governing dynamics, portend broad applicability in the burgeoning field of topological spin textures.
Pulmonary Mycobacterium tuberculosis (Beijing strain infection in a stray dog : clinical communication

Directory of Open Access Journals (Sweden)

S.D.C. Parsons

2008-05-01

Full Text Available Mycobacterium tuberculosis infection in dogs is rarely reported and has not previously been documented in South Africa. A case of a stray Maltese crossbreed dog with extensive multifocal pulmonary tuberculosis due to M. tuberculosis is described. Pulmonary granulomas in this case were poorly encapsulated and contained large numbers of acid-fast bacteria, highlighting the potential for infected companion animals to excrete the pathogen. Treatment of canine tuberculosis is generally not advised, and for this reason, euthanasia of diseased animals must be advocated in most instances. Physicians and veterinarians must be aware that companion animals with active disease caused by M. tuberculosis could act as a potential source of infection.
Molecular and serological surveillance of canine enteric viruses in stray dogs from Vila do Maio, Cape Verde.

Science.gov (United States)

Castanheira, Pedro; Duarte, Ana; Gil, Solange; Cartaxeiro, Clara; Malta, Manuel; Vieira, Sara; Tavares, Luis

2014-04-23

Infections caused by canine parvovirus, canine distemper virus and canine coronavirus are an important cause of mortality and morbidity in dogs worldwide. Prior to this study, no information was available concerning the incidence and prevalence of these viruses in Cape Verde archipelago. To provide information regarding the health status of the canine population in Vila do Maio, Maio Island, Cape Verde, 53 rectal swabs were collected from 53 stray dogs during 2010 and 93 rectal swabs and 88 blood samples were collected from 125 stray dogs in 2011. All rectal swabs (2010 n = 53; 2011 n = 93) were analysed for the presence of canine parvovirus, canine distemper virus and canine coronavirus nucleic acids by quantitative PCR methods. Specific antibodies against canine distemper virus and canine parvovirus were also assessed (2011 n = 88).From the 2010 sampling, 43.3% (23/53) were positive for canine parvovirus DNA, 11.3% (6/53) for canine distemper virus RNA and 1.9% (1/53) for canine coronavirus RNA. In 2011, the prevalence values for canine parvovirus and canine coronavirus were quite similar to those from the previous year, respectively 44.1% (41/93), and 1.1% (1/93), but canine distemper virus was not detected in any of the samples analysed (0%, 0/93). Antibodies against canine parvovirus were detected in 71.6% (63/88) blood samples and the seroprevalence found for canine distemper virus was 51.1% (45/88). This study discloses the data obtained in a molecular and serological epidemiological surveillance carried out in urban populations of stray and domestic animals. Virus transmission and spreading occurs easily in large dog populations leading to high mortality rates particularly in unvaccinated susceptible animals. In addition, these animals can act as disease reservoirs for wild animal populations by occasional contact. Identification of susceptible wildlife of Maio Island is of upmost importance to evaluate the risk of pathogen spill over from

Reduction of short wavelength reflectance of multi-wall carbon nanotubes through ultraviolet laser irradiation

Science.gov (United States)

Stephens, Michelle S.; Simonds, Brian J.; Yung, Christopher S.; Conklin, Davis; Livigni, David J.; Oliva, Alberto Remesal; Lehman, John H.

2018-05-01

Multi-wall carbon nanotube coatings are used as broadband, low-reflectance absorbers for bolometric applications and for stray light control. They are also used as high emittance blackbody radiators. Irradiation of single wall carbon nanotubes with ultraviolet (UV) laser light has been shown to remove amorphous carbon debris, but there have been few investigations of the interaction of UV light with the more complex physics of multi-wall carbon nanotubes. We present measurements of reflectance and surface morphology before and after exposure of multi-wall carbon nanotube coatings to 248 nm UV laser light. We show that UV exposure reduces the reflectivity at wavelengths below 600 nm and present modeling of the thermal cycling the UV exposure causes at the surface of the carbon nanotubes. This effect can be used to flatten the spectral shape of the reflectivity curve of carbon nanotube absorber coatings used for broadband applications. Finally, we find that the effect of UV exposure depends on the nanotube growth process.
Enabling Junction Temperature Estimation via Collector-Side Thermo-Sensitive Electrical Parameters through Emitter Stray Inductance in High-Power IGBT Modules

DEFF Research Database (Denmark)

Luo, Haoze; Li, Wuhua; Iannuzzo, Francesco

2018-01-01

This paper proposes the adoption of the inherent emitter stray inductance LeE in high-power insulated gate bipolar transistor (IGBT) modules as a new dynamic thermo-sensitive electrical parameter (d-TSEP). Furthermore, a family of 14 derived dynamic TSEP candidates has been extracted and classified...
Weight reduction of automobile parts using light metals. Keikinzoku shiyo ni yoru jidosha buhin no keiryoka

Energy Technology Data Exchange (ETDEWEB)

Hayashi, S [Toyota Motor Corp., Aichi (Japan)

1992-12-25

Weight reduction of automobiles is required from the viewpoint of reduction of CO2 emission and energy conservation. Comparing a car with another one of almost the same size and performance with 1% reduced weight, combustion efficiency of the latter can be improved by 0.5-0.8%. This report introduces several examples, in which steel parts are replaced with light alloy parts to reduce car weight, and describes the future perspective. Concerning a cylinder block which is the heaviest part among engine parts, a block made of aluminum alloy with no cast liner has been developed. There is also an example of an oil pan adopting aluminum die-cast for a part of it. A valve lifter made of aluminum alloy has been developed for valve system parts and has contributed to friction loss, noise reduction, and improvement of fuel consumption. As for steering system parts, a steering bracket made of Mg alloy die-cast has been developed. The use of light alloy parts, in general, increases material cost. Therefore it is now required to build up closer connection between designs and production techniques and to improve reliability of casting and forging technologies. 5 refs., 20 figs.
UV Blocking Glass: Low Cost Filters for Visible Light Photocatalytic Assessment

Directory of Open Access Journals (Sweden)

Charles W. Dunnill

2014-01-01

Full Text Available A number of commercially available art protection products have been compared and assessed for their suitability as UV blocking filters in the application of “visible light” photocatalytic research. Many groups claiming visible light photocatalytic success employ filters to block out stray UV radiation in order to justify that their photocatalysts are indeed visible light photocatalysts and not UV light photocatalysts. These filters come in varying degrees of ability and price and many authors fail to correctly characterise their filters in individual papers. The use of effective filters to prevent both false positive and false negative results is important to maintain scientific rigor and create accurate understanding of the subject. The optimum UV filter would have the highest UV blocking properties (<390 nm and simultaneously the highest visible light transmission (390–750 nm. Single and double layers of each of the glass products were assessed as well as laminate products. The conclusions show an inexpensive and highly effective setup for the conduction of visible light photochemistry that should be incorporated as a standard part in any researcher’s work where the claim of visible light activity is made.
Radiation protection measurements with the variance-covariance method in the stray radiation fields from photon and proton therapy facilities

DEFF Research Database (Denmark)

Lillhök, J.; Persson, L.; Andersen, Claus E.

2017-01-01

, the dose-average lineal energy, the dose-average quality factor and the dose equivalent. The neutron component measured by the detectors at the proton beam was studied through Monte Carlo simulations using the code MCNP6. In the photon beam the stray absorbed dose ranged between 0.3 and 2.4 μGy per monitor...
Adaption of an array spectroradiometer for total ozone column retrieval using direct solar irradiance measurements in the UV spectral range

Science.gov (United States)

Zuber, Ralf; Sperfeld, Peter; Riechelmann, Stefan; Nevas, Saulius; Sildoja, Meelis; Seckmeyer, Gunther

2018-04-01

A compact array spectroradiometer that enables precise and robust measurements of solar UV spectral direct irradiance is presented. We show that this instrument can retrieve total ozone column (TOC) accurately. The internal stray light, which is often the limiting factor for measurements in the UV spectral range and increases the uncertainty for TOC analysis, is physically reduced so that no other stray-light reduction methods, such as mathematical corrections, are necessary. The instrument has been extensively characterised at the Physikalisch-Technische Bundesanstalt (PTB) in Germany. During an international total ozone measurement intercomparison at the Izaña Atmospheric Observatory in Tenerife, the high-quality applicability of the instrument was verified with measurements of the direct solar irradiance and subsequent TOC evaluations based on the spectral data measured between 12 and 30 September 2016. The results showed deviations of the TOC of less than 1.5 % from most other instruments in most situations and not exceeding 3 % from established TOC measurement systems such as Dobson or Brewer.
Facile synthesis of amino-functionalized titanium metal-organic frameworks and their superior visible-light photocatalytic activity for Cr(VI) reduction

International Nuclear Information System (INIS)

Wang, Hou; Yuan, Xingzhong; Wu, Yan; Zeng, Guangming; Chen, Xiaohong; Leng, Lijian; Wu, Zhibin; Jiang, Longbo; Li, Hui

2015-01-01

Highlights: • NH 2 functionalized MIL-125(Ti) was fabricated by a facile solvothermal method. • The photocatalyst could reduce Cr(VI)–Cr(III) under visible light irradiation. • The Ti 3+ –Ti 4+ intervalence electron transfer is important for Cr(VI) reduction. • Used NH 2 -MIL-125(Ti) can be recycled for the photocatalytic reduction. - Abstract: Porous metal-organic frameworks (MOFs) have been arousing a great interest in exploring the application of MOFs as photocatalyst in environment remediation. In this work, two different MOFs, Ti-benzenedicarboxylate (MIL-125(Ti)) and amino-functionalized Ti-benzenedicarboxylate (NH 2 -MIL-125(Ti)) were successfully synthesized via a facile solvothermal method. The MIL-125(Ti) and NH 2 -MIL-125(Ti) were well characterized by XRD, SEM, XPS, N 2 adsorption–desorption measurements, thermogravimetric analysis and UV–vis diffuse reflectance spectra (DRS). It is revealed that the NH 2 -MIL-125(Ti) has well crystalline lattice, large surface area and mesoporous structure, chemical and thermal stability, and enhanced visible-light absorption up to 520 nm, which was associated with the chromophore (amino group) in the organic linker. Compared with MIL-125(Ti), NH 2 -MIL-125(Ti) exhibited more efficient photocatalytic activity for Cr(VI) reduction from aqueous solution under visible-light irradiation. The addition of hole scavenger, the hole scavenger concentration and the pH value of the reaction solution played important roles in the photo-catalytic reduction of Cr(VI). The presence of Ti 3+ –Ti 4+ intervalence electron transfer was the main reason for photo-excited electrons transportation from titanium-oxo clusters to Cr(VI), facilitating the Cr(VI) reduction under the acid condition. It was demonstrated that amino-functionalized Ti(IV)-based MOFs could be promising visible-light photocatalysts for the treatment of Cr(VI)-contained wastewater
Some observations on stray magnetic fields and power outputs from short-wave diathermy equipment

Energy Technology Data Exchange (ETDEWEB)

Lau, R.W.M.; Dunscombe, P.B.

1984-04-01

Recent years have seen increasing interest in the possible hazards arising from the use of nonionizing electromagnetic radiation. Relatively large and potentially hazardous fields are to be found in the vicinity of short-wave and microwave equipment used in physiotherapy departments to produce therapeutic temperature rises. This note reports the results of measurements of the stray magnetic field and power output of a conventional short-wave diathermy unit when applied to tissue-equivalent phantoms. The dependence of these quantities on the variables, i.e. power setting of the unit, capacitor plate size, phantom size and phantom-capacitor plate separation, are discussed.
Prevalence of Echinococcus granulosus taeniasis in stray dogs in the region of Constantine (North-East Algeria).

Science.gov (United States)

Kohil, K; Benchikh El Fegoun, M C; Gharbi, M

2017-10-01

In North Africa, the domestic dog is regarded as the main reservoir for infection by Echinococcus granulosus of domestic livestock and man. In Algeria, there is very little data on the rate of infestation of dogs, while the prevalence of E. granulosus in the definitive host is a very reliable marker of the potential risk of transmission of cystic tapeworm to humans and livestock. To find out this information, a survey was conducted to assess the prevalence of infection with E. granulosus in stray dogs in the region of Constantine (North-East Algeria). We autopsied and examined 120 stray dogs, 22 (18.3%) of which were infected with E. granulosus, with an average intensity of infestation of 249 worms. The prevalence in the area of survey was evaluated: 15.5% (14/90) and 26.6% (8/30) dogs were parasitized by E. granulosus in urban and rural areas respectively. The influence of age on the rate of infection was very marked. In addition, the appreciation of the prevalence of parasitism by cestodes as a whole showed that 56 (46.6%) animals out of 120 were infected. Facing such a situation of endemic tapeworm parasitism, with a potential risk of transmission to humans, there is an urgent need to take measures to control and break the epidemiological cycles of the parasite.
Stray dogs and cats as potential sources of soil contamination with zoonotic parasites.

Science.gov (United States)

Szwabe, Katarzyna; Blaszkowska, Joanna

2017-03-22

The main source of many zoonoses is soil contaminated with feline and canine faeces. Thus, the aim of this study was to estimate the prevalence of intestinal parasites in stray dogs and cats adopted in Lodz shelter (Poland). In total, 163 faecal samples were collected from 95 dogs and 68 cats from 2011 to 2012. The samples were processed by sedimentation techniques using Mini Parasep®SF. Six parasite genera belonging to protozoa, cestoda, and nematoda, were found in dogs, while eight were found in cats. Out of the 163 fecal samples, 37.4% were positive for the presence at least one species of intestinal parasites. The majority of positive dog samples contained eggs from Toxocara and Trichuris genera, and the family Ancylostomatidae, while Toxocara and Taenia eggs, as well as Cystoisospora oocysts, predominated in cat faeces. A significantly higher prevalence of parasites was noted in cats (48.5%) than in dogs (29.5%) (χ2=6.15, P=0.013). The Toxocara genus was the most prevalent parasite in both populations; eggs were found in 27.9% and 16.8% of cats and dogs, respectively. Animals younger than 12 months of age showed higher infection rates with Toxocara, but differences were not statistically significant. The average numbers of Toxocara eggs/gram of faeces in positive puppy and kitten samples were over 5 and 7 times higher than in older dogs and cats, respectively. Mixed infection were found in dogs (5.3%) and cats (8.8%). Cat faeces represent a more important potential source of environmental contamination with zoonotic parasites than dog faeces. Among the detected parasites of stray dogs and cats, Toxocara present an important zoonotic risk for the local human population, especially children.
Long-term greenhouse gas emission and petroleum reduction goals: Evolutionary pathways for the light-duty vehicle sector

International Nuclear Information System (INIS)

Kromer, Matthew A.; Bandivadekar, Anup; Evans, Christopher

2010-01-01

To meet long-term environmental and energy security goals, the United States must reduce petroleum use in the light-duty vehicle fleet by 70% and greenhouse gas emissions by a factor of ten compared to business-as-usual growth projections for the year 2050. A wedge-based approach was used to quantify the scope of the problem in real terms, and to develop options for meeting mid-century targets. Four mitigation mechanisms were considered: (1) improvements in near-term vehicle technologies; (2) emphasis on low-carbon biofuels; (3) de-carbonization of the electric grid; and (4) demand-side travel-reduction initiatives. Projections from previous studies were used to characterize the potential of individual mitigation mechanisms, which were then integrated into a light-duty vehicle fleet model; particular emphasis was given to systemic constraints on scale and rates of change. Based on these projections, two different greenhouse gas (GHG) mitigation implementation plans were considered ('evolutionary' and 'aggressive'). Fleet model projections indicate that both the evolutionary and aggressive approaches can effectively end US dependence on foreign oil, but achieving an 80% GHG reduction requires changes that extend significantly beyond even the aggressive case, which was projected to achieve a 65% reduction.
Visible light-driven O2 reduction by a porphyrin-laccase system.

Science.gov (United States)

Lazarides, Theodore; Sazanovich, Igor V; Simaan, A Jalila; Kafentzi, Maria Chrisanthi; Delor, Milan; Mekmouche, Yasmina; Faure, Bruno; Réglier, Marius; Weinstein, Julia A; Coutsolelos, Athanassios G; Tron, Thierry

2013-02-27

Several recent studies have shown that the combination of photosensitizers with metalloenzymes can support a light-driven multielectron reduction of molecules such as CO(2) or HCN. Here we show that the association of the zinc tetramethylpyridinium porphyrin (ZnTMPyP(4+)) photosensitizer with the multicopper oxidase (MCO) laccase allows to link the oxidation of an organic molecule to the four electrons reduction of dioxygen into water. The enzyme is photoreduced within minutes with porphyrin/enzyme ratio as low as 1:40. With a 1:1 ratio, the dioxygen consumption rate is 1.7 μmol L(-1) s(-1). Flash photolysis experiments support the formation of the triplet excited state of ZnTMPyP(4+) which reduces the enzyme to form a radical cation of the porphyrin with a k(ET) ≈ 10(7) s(-1) M(-1). The long-lived triplet excited state of the ZnTMPyP(4+) (τ(0) = 0.72 ms) accounts for a substantial electron-transfer quantum yield, φ(ET) = 0.35. Consequently, the enzyme-dependent photo-oxidation of the electron donor occurs with a turnover of 8 min(-1) for the one-electron oxidation process, thereby supporting the suitability of such enzyme/sensitizer hybrid systems for aerobic photodriven transformations on substrates. This study is the first example of a phorphyrin-sensitized four-electron reduction of an enzyme of the MCO family, leading to photoreduction of dioxygen into water.
Countering the stray magnetic field of the CUSP trap by using additional coils

CERN Document Server

Thole, Jelle

2016-01-01

The ASACUSA experiment at the Antiproton Decelerator (AD) at CERN tries to measure the Hyperfine Structure (HFS) of Antihydrogen (H ̄) using a Rabi spectroscopy set-up. In measuring this HFS it will yield a very precise test of CPT-symmetry. For this set-up to work a homogeneous magnetic field is needed in the cavity where the Hyperfine transition of H ̄ occurs. Due to the stray fields from the CUSP trap, where H ̄ is produced, additional coils are needed to counter these fields. It is found, using COMSOL simulations, that two coils are suitable for this. Leading to a relative standard deviation of the magnetic field of σB/B = 1.06%.
Prevalence and Potential Risk Factors for Bartonella Infection in Tunisian Stray Dogs.

Science.gov (United States)

Belkhiria, Jaber; Chomel, Bruno B; Ben Hamida, Taoufik; Kasten, Rickie W; Stuckey, Matthew J; Fleischman, Drew A; Christopher, Mary M; Boulouis, Henri-Jean; Farver, Thomas B

2017-06-01

Bartonellae are blood-borne and vector-transmitted pathogens, some are zoonotic, which have been reported in several Mediterranean countries. Transmission from dogs to humans is suspected, but has not been clearly demonstrated. Our objectives were to determine the seroprevalence of Bartonella henselae, Bartonella vinsonii subsp. berkhoffii, Bartonella clarridgeiae, and Bartonella bovis (as a proxy for Candidatus Bartonella merieuxii) in stray dogs from Tunisia, identify the Bartonella species infecting the dogs and evaluate potential risk factors for canine infection. Blood samples were collected between January and November 2013 from 149 dogs in 10 Tunisian governorates covering several climatic zones. Dog-specific and geographic variables were analyzed as potential risk factors for Bartonella spp. seropositivity and PCR-positivity. DNA was extracted from the blood of all dogs and tested by PCR for Bartonella, targeting the ftsZ and rpoB genes. Partial sequencing was performed on PCR-positive dogs. Twenty-nine dogs (19.5%, 95% confidence interval: 14-27.4) were seropositive for one or more Bartonella species, including 17 (11.4%) for B. vinsonii subsp. berkhoffii, 14 (9.4%) for B. henselae, 13 (8.4%) for B. clarridgeiae, and 7 (4.7%) for B. bovis. Statistical analysis revealed a few potential risk factors, mainly dog's age and breed, latitude and average winter temperature. Twenty-two (14.8%) dogs, including 8 of the 29 seropositive dogs, were PCR-positive for Bartonella based on the ftsZ gene, with 18 (81.8%) of these 22 dogs also positive for the rpoB gene. Partial sequencing showed that all PCR-positive dogs were infected with Candidatus B. merieuxii. Dogs from arid regions and regions with cold average winter temperatures were less likely to be PCR-positive than dogs from other climatic zones. The widespread presence of Bartonella spp. infection in Tunisian dogs suggests a role for stray dogs as potential reservoirs of Bartonella species in Tunisia.
MoS_2/reduced graphene oxide hybrid with CdS nanoparticles as a visible light-driven photocatalyst for the reduction of 4-nitrophenol

International Nuclear Information System (INIS)

Peng, Wen-chao; Chen, Ying; Li, Xiao-yan

2016-01-01

Highlights: • MoS_2/rGO hybrid is synthesized using a one-step hydrothermal method. • MoS_2/rGO hybrid is used as the support and cocatalyst for CdS nanoparticles. • CdS-MoS_2/rGO composite is effective photocatalyst for 4-NP reduction in visible light. • Ammonium formate is an effective sacrificial agent for 4-NP photocatalytic reduction. - Abstract: Photocatalytic reduction of nitroaromatic compounds to aromatic amines using visible light is an attractive process that utilizes sunlight as the energy source for the chemical conversions. Herewith we synthesized a composite material consisting of CdS nanoparticles grown on the surface of MoS_2/reduced graphene oxide (rGO) hybrid as a novel photocatalyst for the reduction of 4-nitrophenol (4-NP). The CdS-MoS_2/rGO composite is shown as a high-performance visible light-driven photocatalyst. Even without a noble-metal cocatalyst, the catalyst exhibited a great activity under visible light irradiation for the reduction of 4-NP to much less toxic 4-aminophenol (4-AP) with ammonium formate as the sacrificial agent. Composite CdS-0.03(MoS_2/0.01rGO) was found to be the most effective photocatalyst for 4-NP reduction. The high photocatalytic performance is apparently resulted from the synergetic functions of MoS_2 and graphene in the composite, i.e. the cocatalysts serve as both the active adsorption sites for 4-NP and electron collectors for the separation of electron-hole pairs generated by CdS nanoparticles. The laboratory results show that the CdS-MoS_2/rGO composite is a low-cost and stable photocatalyst for effective reduction and detoxification of nitroaromatic compounds using solar energy.
Facile synthesis of amino-functionalized titanium metal-organic frameworks and their superior visible-light photocatalytic activity for Cr(VI) reduction

Energy Technology Data Exchange (ETDEWEB)

Wang, Hou [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082 (China); Yuan, Xingzhong, E-mail: yxz@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082 (China); Wu, Yan [College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); Zeng, Guangming [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082 (China); Chen, Xiaohong [School of Business, Central South University, Changsha 410083 (China); Leng, Lijian; Wu, Zhibin; Jiang, Longbo [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082 (China); Li, Hui [Institute of Bio-energy, Hunan Academy of Forestry, Changsha 410004 (China)

2015-04-09

Highlights: • NH{sub 2} functionalized MIL-125(Ti) was fabricated by a facile solvothermal method. • The photocatalyst could reduce Cr(VI)–Cr(III) under visible light irradiation. • The Ti{sup 3+}–Ti{sup 4+} intervalence electron transfer is important for Cr(VI) reduction. • Used NH{sub 2}-MIL-125(Ti) can be recycled for the photocatalytic reduction. - Abstract: Porous metal-organic frameworks (MOFs) have been arousing a great interest in exploring the application of MOFs as photocatalyst in environment remediation. In this work, two different MOFs, Ti-benzenedicarboxylate (MIL-125(Ti)) and amino-functionalized Ti-benzenedicarboxylate (NH{sub 2}-MIL-125(Ti)) were successfully synthesized via a facile solvothermal method. The MIL-125(Ti) and NH{sub 2}-MIL-125(Ti) were well characterized by XRD, SEM, XPS, N{sub 2} adsorption–desorption measurements, thermogravimetric analysis and UV–vis diffuse reflectance spectra (DRS). It is revealed that the NH{sub 2}-MIL-125(Ti) has well crystalline lattice, large surface area and mesoporous structure, chemical and thermal stability, and enhanced visible-light absorption up to 520 nm, which was associated with the chromophore (amino group) in the organic linker. Compared with MIL-125(Ti), NH{sub 2}-MIL-125(Ti) exhibited more efficient photocatalytic activity for Cr(VI) reduction from aqueous solution under visible-light irradiation. The addition of hole scavenger, the hole scavenger concentration and the pH value of the reaction solution played important roles in the photo-catalytic reduction of Cr(VI). The presence of Ti{sup 3+}–Ti{sup 4+} intervalence electron transfer was the main reason for photo-excited electrons transportation from titanium-oxo clusters to Cr(VI), facilitating the Cr(VI) reduction under the acid condition. It was demonstrated that amino-functionalized Ti(IV)-based MOFs could be promising visible-light photocatalysts for the treatment of Cr(VI)-contained wastewater.
A report on the alimentary canal helminthic infestation of stray and pet dogs in Tabriz

Directory of Open Access Journals (Sweden)

Y Gharedaghi

2008-08-01

Full Text Available From September to December 2007, fecal specimens of 100 stray and pet dogs in Tabriz were examined by saturated salt flotation and Telmann sedimentation methods to determine the prevalence of gastrointestinal helminth infestation. Helminth infestation was encountered in 31 (31% of the fecal samples examined. The eggs of two different cestodes and three different nematodes were identified in the contaminated fecal samples. The helminth eggs found were identified as Taenia hydatigena (4%, Dipylidium caninum (6%, Toxocara canis (10%, Ancylostoma caninum (6% and Trichuris vulpis (5%. No trematoda eggs and nematode larvae were found in this study.
Measurement and application of bidirectional reflectance distribution function

Science.gov (United States)

Liao, Fei; Li, Lin; Lu, Chengwen

2016-10-01

When a beam of light with certain intensity and distribution reaches the surface of a material, the distribution of the diffused light is related to the incident angle, the receiving angle, the wavelength of the light and the types of the material. Bidirectional Reflectance Distribution Function (BRDF) is a method to describe this distribution. For an optical system, the optical and mechanical materials' BRDF are unique, and if we want to calculate stray light of the system we should know the correct BRDF data of the whole materials. There are fundamental significances in the area of space remote sensor where BRDF is needed in the precise radiation calibration. It is also important in the military field where BRDF can be used in the object identification and target tracking, etc. In this paper, 11 kinds of aerospace materials' BRDF are measured and more than 310,000 groups of BRDF data are achieved , and also a BRDF database is established in China for the first time. With the BRDF data of the database, we can create the detector model, build the stray light radiation surface model in the stray light analysis software. In this way, the stray radiation on the detector can be calculated correctly.
CO_2 emissions reduction of Chinese light manufacturing industries: A novel RAM-based global Malmquist–Luenberger productivity index

International Nuclear Information System (INIS)

Emrouznejad, Ali; Yang, Guo-liang

2016-01-01

Climate change has become one of the most challenging issues facing the world. Chinese government has realized the importance of energy conservation and prevention of the climate changes for sustainable development of China's economy and set targets for CO_2 emissions reduction in China. In China industry contributes 84.2% of the total CO_2 emissions, especially manufacturing industries. Data envelopment analysis (DEA) and Malmquist productivity (MP) index are the widely used mathematical techniques to address the relative efficiency and productivity of a group of homogenous decision making units, e.g. industries or countries. However, in many real applications, especially those related to energy efficiency, there are often undesirable outputs, e.g. the pollutions, waste and CO_2 emissions, which are produced inevitably with desirable outputs in the production. This paper introduces a novel Malmquist–Luenberger productivity (MLP) index based on directional distance function (DDF) to address the issue of productivity evolution of DMUs in the presence of undesirable outputs. The new RAM (Range-adjusted measure)-based global MLP index has been applied to evaluate CO_2 emissions reduction in Chinese light manufacturing industries. Recommendations for policy makers have been discussed. - Highlights: •CO_2 emissions reduction in Chinese light manufacturing industries are measured. •A novel RAM based Malmquist–Luenberger productivity index has been developed. •Recommendation to policy makers for reducing CO_2 reduction in China are given.
High potential oxidation-reduction titration of absorbance changes induced by pulsed laser and continuous light in chromatophores of photosynthesizing bacteria Rhodospirillum rubrum and Ectothiorhodospira shaposhnikovii

International Nuclear Information System (INIS)

Remennikov, S.M.; Chamorovsky, S.K.; Kononenko, A.A.; Venediktov, P.S.; Rubin, A.B.

1975-01-01

The photoreactions, activated both by pulsed laser and continuous light were studied in the membranes of isolated bacterial chromatophores poised at different oxidation-reduction potentials over a range of +200 mV to +500 mV. In Rhodospirillum rubrum a midpoint potential of oxidation-reduction curves for the laser-induced positive absorbance changes centred around 430 nm and carotenoid red shifts coincides with that for continuous light-induced absorbance changes, bleaching at 865 nm and blue shift at 800 nm, of the photosynthetic reaction centre bacteriochlorophyll. In Ectothiorhodospira shaposhnikovii the photosynthetic reaction centre bacteriochlorophyll, its photooxidation can be seen as light-induced absorbance changes, bleaching at 890 nm, blue shift at 800 nm and broad band appearance near 440 nm, has a midpoint oxidation-reduction potential of +390 mV at pH 7.4. The analysis of the oxidation-reduction titration curves for the high-potential c-type cytochrome absorbance changes induced both by pulsed laser and continuous light allowed to show that at least two haems of this cytochrome with a midpoint potential of +290 mV (pH 7.4), associated with each reaction centre bacteriochlorophyll, can donate electrons to the oxidized pigment directly

Design and testing of a magnetic shield for the Thomson scattering photomultiplier tubes in the stray fields of the ERASMUS tokamak

International Nuclear Information System (INIS)

Desoppere, E.; Van Oost, G.

1983-01-01

A multiple coaxial shield system has been designed for the photomultiplier tubes of the ERASMUS tokamak Thomson scattering diagnostic. A stray field of 75 x 10 -4 T was reduced to 0.01 x 10 -4 T for a field parallel to the tube axis, and to 0.03 x 10 -4 T for a perpendicular field
Riboflavin and ultraviolet light for pathogen reduction of murine cytomegalovirus in blood products.

Science.gov (United States)

Keil, Shawn D; Saakadze, Natia; Bowen, Richard; Newman, James L; Karatela, Sulaiman; Gordy, Paul; Marschner, Susanne; Roback, John; Hillyer, Christopher D

2015-04-01

Two studies were performed to test the effectiveness of riboflavin and ultraviolet (UV) light treatment (Mirasol PRT, Terumo BCT) against murine cytomegalovirus (MCMV). The first study utilized immune-compromised mice to measure the reduction of cell-free MCMV. A second study used a murine model to evaluate the ability of Mirasol PRT to prevent transfusion-transmitted (TT)-MCMV infection. Human plasma was inoculated with MCMV and then treated with Mirasol PRT. The viral titer was measured using an infectious dose 50% assay in nude mice. Mice were euthanized on Day 10 posttransfusion, and their spleens were tested for the presence of MCMV DNA using polymerase chain reaction (PCR). Mirasol PRT was also evaluated to determine its effectiveness in preventing TT-MCMV in platelets (PLTs) stored in PLT additive solution. PLTs were inoculated with either cell-associated MCMV or cell-free MCMV and then treated with Mirasol PRT. Mice were transfused with treated or untreated product and were euthanized 14 days posttransfusion. Blood and spleens were assayed for MCMV DNA by real-time-PCR. Using nude mice to titer MCMV, a modest 2.1-log reduction was observed in plasma products after Mirasol PRT treatment. TT-MCMV was not observed in the mouse transfusion model when either cell-free or cell-associated MCMV was treated with Mirasol PRT; MCMV transmission was uniformly observed in mice transfused with untreated PLTs. These results suggest that using riboflavin and UV light treatment may be able to reduce the occurrence of transmission of human CMV from infectious PLTs and plasma units. © 2014 AABB.
Stray current induced corrosion in lightning rod cables of 525 kV power lines towers: a case study

OpenAIRE

Wojcicki, F. R.; Negrisoli, M. E. M.; Franco, C. V.

2003-01-01

With the growth of several areas in modem society, the necessity to generate and carry electrical energy to big cities has greatly increased. Cables supported by power towers with galvanized steel foundation usually carry energy. As the foundations are underground they may cause high rates of corrosion. These are usually detected by a conventional potential measurement using a Cu/CuSO₄ reference electrode. It is believed that corrosion results from stray currents that f...
Progress on Thomson scattering in the Pegasus Toroidal Experiment

International Nuclear Information System (INIS)

Schlossberg, D J; Bongard, M W; Fonck, R J; Schoenbeck, N L; Winz, G R

2013-01-01

A novel Thomson scattering system has been implemented on the Pegasus Toroidal Experiment where typical densities of 10 19 m −3 and electron temperatures of 10 to 500 eV are expected. The system leverages technological advances in high-energy pulsed lasers, volume phase holographic (VPH) diffraction gratings, and gated image intensified (ICCD) cameras to provide a relatively low-maintenance, economical, robust diagnostic system. Scattering is induced by a frequency-doubled, Q-switched Nd:YAG laser (2 J at 532 nm, 7 ns FWHM pulse) directed to the plasma over a 7.7 m long beam path, and focused to 80%) and fast-gated ICCDs (gate > 2 ns, Gen III intensifier) with high-throughput (F/1.8), achromatic lensing. A stray light mitigation facility has been implemented, consisting of a multi-aperture optical baffle system and a simple beam dump. Successful stray light reduction has enabled detection of scattered signal, and Rayleigh scattering has been used to provide a relative calibration. Initial temperature measurements have been made and data analysis algorithms are under development
Progress on Thomson scattering in the Pegasus Toroidal Experiment

Science.gov (United States)

Schlossberg, D. J.; Bongard, M. W.; Fonck, R. J.; Schoenbeck, N. L.; Winz, G. R.

2013-11-01

A novel Thomson scattering system has been implemented on the Pegasus Toroidal Experiment where typical densities of 1019 m-3 and electron temperatures of 10 to 500 eV are expected. The system leverages technological advances in high-energy pulsed lasers, volume phase holographic (VPH) diffraction gratings, and gated image intensified (ICCD) cameras to provide a relatively low-maintenance, economical, robust diagnostic system. Scattering is induced by a frequency-doubled, Q-switched Nd:YAG laser (2 J at 532 nm, 7 ns FWHM pulse) directed to the plasma over a 7.7 m long beam path, and focused to VPH transmission gratings (eff. > 80%) and fast-gated ICCDs (gate > 2 ns, Gen III intensifier) with high-throughput (F/1.8), achromatic lensing. A stray light mitigation facility has been implemented, consisting of a multi-aperture optical baffle system and a simple beam dump. Successful stray light reduction has enabled detection of scattered signal, and Rayleigh scattering has been used to provide a relative calibration. Initial temperature measurements have been made and data analysis algorithms are under development.
PAPR reduction based on tone reservation scheme for DCO-OFDM indoor visible light communications.

Science.gov (United States)

Bai, Jurong; Li, Yong; Yi, Yang; Cheng, Wei; Du, Huimin

2017-10-02

High peak-to-average power ratio (PAPR) leads to out-of-band power and in-band distortion in the direct current-biased optical orthogonal frequency division multiplexing (DCO-OFDM) systems. In order to effectively reduce the PAPR with faster convergence and lower complexity, this paper proposes a tone reservation based scheme, which is the combination of the signal-to-clipping noise ratio (SCR) procedure and the least squares approximation (LSA) procedure. In the proposed scheme, the transmitter of the DCO-OFDM indoor visible light communication (VLC) system is designed to transform the PAPR reduced signal into real-valued positive OFDM signal without doubling the transmission bandwidth. Moreover, the communication distance and the light emitting diode (LED) irradiance angle are taking into consideration in the evaluation of the system bit error rate (BER). The PAPR reduction efficiency of the proposed scheme is remarkable for DCO-OFDM indoor VLC systems.
Stray current induced corrosion in lightning rod cables of 525 kV power lines towers: a case study

International Nuclear Information System (INIS)

Wojcicki, F. R.; Negrisoli, M. E. M.; Franco, C. V.

2003-01-01

With the growth of several areas in modern society, the necessity to generate and carry electrical energy to big cities has greatly increased. Cables supported by power towers with galvanized steel foundation usually carry energy. As the foundations are underground they may cause high rates of corrosion. These are usually detected by a conventional potential measurement using a Cu/CuSO 4 reference electrode. It is believed that corrosion results from stray currents that flow through the ground to close the loop between neighboring towers. Stray currents originate in the lightning rod cables of the power line towers, induced by the strong electromagnetic and electric fields of the energized power lines. The intensity and direction of those currents were measured, indicating substantial values of both their AC and DC components. The potential of the tower ground system, measured in the perpendicular direction of the main axis of the power line, was plotted as a function of the distance to the tower base. The results clearly indicated the tendency to corrosive attack in the anodic towers as reflected by the slope of the plot, whereas no signs of corrosion could be found in the reverse slope, confirming the visual inspection of the foundation. The profile of the potential plots could be changed providing the electric insulation of the lightning rod cable. (Author) 8 refs
Endoparasites of Stray Dogs in Mashhad, Khorasan Razavi Province, Northeast Iran with Special Reference to Zoonotic Parasites

Directory of Open Access Journals (Sweden)

Amir Adinezadeh

2013-09-01

Full Text Available Background: To find out different species of helminthes and blood/tissue protozoan parasites of stray dogs and their potential role for transmission of zoonotic species to human in Mashhad, Khorasan Razavi Province, northeast Iran, during 2008-2009.Methods: Totally, 100 stray dogs were selected among Mashhad municipal collection from different sites of the city. Internal organs were examined for any parasites. Helminthes were identified based on morphological characteristics. Smears prepared from peripheral blood as well as liver, spleen and any skin lesion were stained by Giemsa and examined microscopically. Samples obtained from spleen were aseptically cultured in three culture media including NNN, Schneider’s Drosophila (HIMEDIA and RPMI1640 (GIBCO for isolation of Leishmania spp. The titer of anti-Leishmania and anti-Toxoplasma antibodies were measured by direct agglutination test (DAT and indirect fluorescent antibody test (IFAT, respectively.Results: 84% of dogs were infected at least with one species of intestinal helminthes. The species of parasites and rate of infection were as follows: Taenia hydatigena (61%, Dipylidium caninum (46%, Mesocestoides lineatus (19%, Echinococcus granulosus (10%, Toxascaris leonina (53% and Toxocara canis (7%. Anti-Leishmania antibodies were detected by DAT in 8 dogs (8% at 1:320 titers and higher. Forty seven dogs (47% showed anti-Toxoplasma titer at 1:10 and 17 (17% showed titer of ≥1:100. No blood parasites were found in prepared blood smears.Conclusion: The high rate of parasitic infection and presence of zoonotic species
Towards a safety case for the use of laser cutting in nuclear decommissioning

International Nuclear Information System (INIS)

Hilton, P.A.

2014-01-01

Some of the requirements in nuclear decommissioning include size reduction of contaminated containers, pipework and other structures manufactured from stainless and other steels. Size reduction is generally performed using mechanical saws or shears, with drawbacks of quick wear, significant applied force, difficult remote operation and addition to contaminated waste mass. The use of lasers for cutting within the context of nuclear decommissioning has been recently demonstrated by TWI and others. In this paper, aspects of drawing together a safety case for using laser beams for cutting in a nuclear decommissioning cell are discussed, via analysis of relevant purpose designed experimental data. Data presented includes assessment of the use of different focal length lenses and the power densities anticipated at distances of up to 3 m from the focal point, as well as beam effects on material behind the cutting zone. An assessment of anticipated material damage from stray beams or unintended exposure to laser light of surrounding items is also presented. Finally materials for effective screening against stray beams during the cutting process have been tested for effectiveness. (authors)
The legal status of cats in New Zealand: a perspective on the welfare of companion, stray, and feral domestic cats (Felis catus).

Science.gov (United States)

Farnworth, Mark J; Dye, Nicholson G; Keown, Natasha

2010-01-01

Pinpointing and safeguarding the welfare status of domestic cats is problematic, especially in New Zealand where cats are introduced predators with significant impact on indigenous fauna. Usually the identification of welfare status depends on conservational, legal, and public attitudes that are often contrasting. Cats may rapidly transgress definitions placed on them, confounding attempts to categorize them. In 1 generation, cats can move from a human-dependent state ("stray" or "companion") to wild ("feral"). Often this categorization uses arbitrary behavioral and or situational parameters; consequent treatment and welfare protection for these cats are similarly affected. Terminology used to describe cats is not equitable across research. However, the New Zealand Animal Welfare (Companion Cats) Code of Welfare 2007 seeks to create a new definition of the terms companion, stray, and feral. It distinguishes between cats who live within and without human social constructs. This legislation mandates that cats in human environments or indirectly dependent on humans cannot be classified as feral. Such definitions may prove vital when safeguarding the welfare of free-living domestic cats and cat colonies.
ZnCr2S4: Highly effective photocatalyst converting nitrate into N2 without over-reduction under both UV and pure visible light.

Science.gov (United States)

Yue, Mufei; Wang, Rong; Cheng, Nana; Cong, Rihong; Gao, Wenliang; Yang, Tao

2016-08-03

We propose several superiorities of applying some particular metal sulfides to the photocatalytic nitrate reduction in aqueous solution, including the high density of photogenerated excitons, high N2 selectivity (without over-reduction to ammonia). Indeed, ZnCr2S4 behaved as a highly efficient photocatalyst, and with the assistance of 1 wt% cocatalysts (RuOx, Ag, Au, Pd, or Pt), the efficiency was greatly improved. The simultaneous loading of Pt and Pd led to a synergistic effect. It offered the highest nitrate conversion rate of ~45 mg N/h together with the N2 selectivity of ~89%. Such a high activity remained steady after 5 cycles. The optimal apparent quantum yield at 380 nm was 15.46%. More importantly, with the assistance of the surface plasma resonance effect of Au, the visible light activity achieved 1.352 mg N/h under full arc Xe-lamp, and 0.452 mg N/h under pure visible light (λ > 400 nm). Comparing to the previous achievements in photocatalytic nitrate removal, our work on ZnCr2S4 eliminates the over-reduction problem, and possesses an extremely high and steady activity under UV-light, as well as a decent conversion rate under pure visible light.
ZnCr2S4: Highly effective photocatalyst converting nitrate into N2 without over-reduction under both UV and pure visible light

Science.gov (United States)

Yue, Mufei; Wang, Rong; Cheng, Nana; Cong, Rihong; Gao, Wenliang; Yang, Tao

2016-08-01

We propose several superiorities of applying some particular metal sulfides to the photocatalytic nitrate reduction in aqueous solution, including the high density of photogenerated excitons, high N2 selectivity (without over-reduction to ammonia). Indeed, ZnCr2S4 behaved as a highly efficient photocatalyst, and with the assistance of 1 wt% cocatalysts (RuOx, Ag, Au, Pd, or Pt), the efficiency was greatly improved. The simultaneous loading of Pt and Pd led to a synergistic effect. It offered the highest nitrate conversion rate of ~45 mg N/h together with the N2 selectivity of ~89%. Such a high activity remained steady after 5 cycles. The optimal apparent quantum yield at 380 nm was 15.46%. More importantly, with the assistance of the surface plasma resonance effect of Au, the visible light activity achieved 1.352 mg N/h under full arc Xe-lamp, and 0.452 mg N/h under pure visible light (λ > 400 nm). Comparing to the previous achievements in photocatalytic nitrate removal, our work on ZnCr2S4 eliminates the over-reduction problem, and possesses an extremely high and steady activity under UV-light, as well as a decent conversion rate under pure visible light.
Model of inter-cell interference phenomenon in 10 nm magnetic tunnel junction with perpendicular anisotropy array due to oscillatory stray field from neighboring cells

Science.gov (United States)

Ohuchida, Satoshi; Endoh, Tetsuo

2018-06-01

In this paper, we propose a new model of inter-cell interference phenomenon in a 10 nm magnetic tunnel junction with perpendicular anisotropy (p-MTJ) array and investigated the interference effect between a program cell and unselected cells due to the oscillatory stray field from neighboring cells by Landau–Lifshitz–Gilbert micromagnetic simulation. We found that interference brings about a switching delay in a program cell and excitation of magnetization precession in unselected cells even when no programing current passes through. The origin of interference is ferromagnetic resonance between neighboring cells. During the interference period, the precession frequency of the program cell is 20.8 GHz, which synchronizes with that of the theoretical precession frequency f = γH eff in unselected cells. The disturbance strength of unselected cells decreased to be inversely proportional to the cube of the distance from the program cell, which is in good agreement with the dependence of stray field on the distance from the program cell calculated by the dipole approximation method.
Rhodium-Coordinated Poly(arylene-ethynylene)-alt-Poly(arylene-vinylene) Copolymer Acting as Photocatalyst for Visible-Light-Powered NAD+/NADH Reduction

Science.gov (United States)

2014-01-01

A 2,2′-bipyridyl-containing poly(arylene-ethynylene)-alt-poly(arylene-vinylene) polymer, acting as a light-harvesting ligand system, was synthesized and coupled to an organometallic rhodium complex designed for photocatalytic NAD+/NADH reduction. The material, which absorbs over a wide spectral range, was characterized by using various analytical techniques, confirming its chemical structure and properties. The dielectric function of the material was determined from spectroscopic ellipsometry measurements. Photocatalytic reduction of nucleotide redox cofactors under visible light irradiation (390–650 nm) was performed and is discussed in detail. The new metal-containing polymer can be used to cover large surface areas (e.g. glass beads) and, due to this immobilization step, can be easily separated from the reaction solution after photolysis. Because of its high stability, the polymer-based catalyst system can be repeatedly used under different reaction conditions for (photo)chemical reduction of NAD+. With this concept, enzymatic, photo-biocatalytic systems for solar energy conversion can be facilitated, and the precious metal catalyst can be recycled. PMID:25130570
Weight reduction of vehicles and light metals; Jidosya no keryoka to keikinzoku zairyo

Energy Technology Data Exchange (ETDEWEB)

Manabe, Akira. [Toyota Motor Corp., Aichi (Japan). Component and System Development Center

1999-08-15

Weight reduction of vehicles (WRV) is a continuous challenge from the beginning of the vehicle history, however the purpose of WRV has been changing by social requirements. Recently automotive industry is facing is facing with the global warmin and the other environmental issues, so we are vast amount of R and D resources to improve the fuel economy. In this paper, the changes of the purpose of WRV and, the relation between fuel economy and WRV, are summarized. And also the current status of light metals usage and the future work for the related material issues, in particuar the corrosion resistance, are brifly mentioned. (author)
Visible light-responded C, N and S co-doped anatase TiO{sub 2} for photocatalytic reduction of Cr(VI)

Energy Technology Data Exchange (ETDEWEB)

Lei, X.F., E-mail: leixuefei69@163.com [School of Resources and Materials, Northeastern University at Qinhuangdao, Qinhuangdao 066004 (China); Institute of Metallurgical Resource and Environmental Engineering, Northeastern University, Shenyang 110819 (China); Liaoning Key Laboratory of Metallurgical Resource Recycling Science, Shenyang 110819 (China); Liaoning Engineering and Technology Research Center of Boron Resource, Comprehensive, Utilization, Shenyang 110819 (China); Liaoning Provincial Universities Key Laboratory of Boron Resource Ecological, Utilization, Technology and Boron Materials, Shenyang 110819 (China); Xue, X.X.; Yang, H. [Institute of Metallurgical Resource and Environmental Engineering, Northeastern University, Shenyang 110819 (China); Liaoning Key Laboratory of Metallurgical Resource Recycling Science, Shenyang 110819 (China); Liaoning Engineering and Technology Research Center of Boron Resource, Comprehensive, Utilization, Shenyang 110819 (China); Liaoning Provincial Universities Key Laboratory of Boron Resource Ecological, Utilization, Technology and Boron Materials, Shenyang 110819 (China); Chen, C.; Li, X.; Pei, J.X.; Niu, M.C.; Yang, Y.T.; Gao, X.Y. [School of Resources and Materials, Northeastern University at Qinhuangdao, Qinhuangdao 066004 (China)

2015-10-15

The (C, N and S) co-doped TiO{sub 2} (TH-TiO{sub 2}) samples were synthesized by a sol-gel method calcined at 500 °C, employing butyl titanate as the titanium source and thiourea as the dopant. The structures of TH-TiO{sub 2} samples were characterized by X-ray diffraction (XRD), Transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), UV–vis diffuse reflectance spectra (DRS), photoluminescence (PL) spectroscopy, Thermo gravimetry and differential thermal analysis (TG-DTA), Scanning electron microscopy (SEM) and nitrogen adsorption–desorption isotherms. The photocatalytic activities were checked through the photocatalytic reduction of Cr(VI) as a model compound under visible light irradiation. The results showed that the thiourea content played an important role on the microstructure and photocatalytic activity of the samples. According to XPS results, (C, N and S) atoms were successfully co-doped into the nanostructures of TH-TiO{sub 2} samples. TH-TiO{sub 2} samples with thiourea: Ti molar ratio of 1.5 exhibits higher photocatalytic activity than that of the other samples under visible light irradiation, which can be attributed to the synergic effect of the pure anatase structure, the higher light absorption characteristics in visible regions, separation efficiency of electron–hole pairs, the specific surface area and the optimum (C, N and S) content. - Graphical abstract: (C, N and S) co-doped TiO{sub 2} samples show good photocatalytic activity for Cr (VI) reduction under visible light irradiation. - Highlights: • (C, N and S) co-doping in TH-TiO{sub 2} samples can promote the formation of the pure anatase structure. • (C, N and S) atoms were successfully co-doped into the nanostructures of TH-TiO{sub 2} samples. • The band gap energy of TH-TiO{sub 2} samples reduced after (C, N and S) co-doping. • (C, N and S) co-doped TiO{sub 2} samples were effective for the photocatalytic reduction of Cr(VI) under visible light
Message Collision Avoidance Protocols for Detecting Stray Nodes in a Scuba Diving Group Using Ultrasonic Multi-Hop Message Communication

Directory of Open Access Journals (Sweden)

Shinya Kaido

2017-12-01

Full Text Available Recent years have seen a growing interest in underwater communication and some progress has been made in this area. However, underwater communication is still immature compared with terrestrial communication. A prime reason for this is that the underwater environment is intrinsically not suitable for propagation of electric waves. Instead, ultrasonic waves are mainly used for underwater communication. Since ultrasonic waves cannot provide sufficient communication speed or capacity, they cannot use existing network technologies, which assume use of radio waves. In particular, communication in shallow water is still an uncharted territory. Few communication technologies are employed in environments where people enjoy scuba diving. This paper addresses problems faced by recreational scuba divers. It proposes constructing an ad hoc mesh-shaped network between divers within a group and use ultrasonic waves as transmission media in order to enable the detection of a stray diver. It also proposes a communication protocol in which messages are relayed in multiple hops, and a message collision avoidance method, which is intended to reduce the rate of packet loss caused by message propagation delay. We have implemented the proposed methods in a network simulator, and compared them with an existing communication method that has no message collision avoidance function, in terms of the packet loss rate, the stray driver detection rate, and the rate of the ability to communicate in multiple hops.
Reduction in global warming due to fuel economy improvements and emissions control of criteria pollutants: New US light-duty vehicles (1968--1991)

Energy Technology Data Exchange (ETDEWEB)

Pitstick, M.E.; Santini, D.J. [Argonne National Lab., IL (United States); Chauhan, H. [Delaware Univ., Newark, DE (United States). Dept. of Civil Engineering

1992-08-01

This paper explores the impact of US emission controls and fuel economy improvements on the global warming potential (GWP) of new light-duty vehicles. Fuel economy improvements have reduced the GWP of both passenger cars and light-duty trucks by lowering the per mile emissions of carbon dioxide (CO{sub 2}). Further GWP reductions have been achieved by emission standards for criteria pollutants: carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NO{sub x}). The GWP of a criteria pollutant was calculated by multiplying the emission rate by a relative global warming factor to obtain a CO{sub 2} equivalent emission rate. Both CO{sub 2} and criteria pollutant emission rates per vehicle have decreased substantially for new light-duty vehicles over the period from 1968 to 1991. Over that period, the GWP from CO{sub 2} was reduced by almost 50% in new vehicles by improving fuel economy. In that same time period, the GWP from criteria pollutants from new vehicles was reduced with emission controls by from 80% to 90% depending on the global warming time frame of interest. Consequently, total reductions in the GWP of new passenger cars and light-duty trucks have been on the order of 55 to 75 percent compared to precontrol (before 1968) new vehicles. However, the reduction in GWP caused by emission control of criteria pollutants has been larger than the reduction caused by improved fuel economy (i.e., reduced CO{sub 2}). The contribution of criteria pollutants to the GWP of precontrol new vehicles was substantial, but their contribution has been reduced significantly due to US emission controls. As a result, the contribution of criteria pollutants to global warming is now much less than the contribution of CO{sub 2} from fuel consumption.
Reduction in global warming due to fuel economy improvements and emissions control of criteria pollutants: New US light-duty vehicles (1968--1991)

Energy Technology Data Exchange (ETDEWEB)

Pitstick, M.E.; Santini, D.J. (Argonne National Lab., IL (United States)); Chauhan, H. (Delaware Univ., Newark, DE (United States). Dept. of Civil Engineering)

1992-01-01

This paper explores the impact of US emission controls and fuel economy improvements on the global warming potential (GWP) of new light-duty vehicles. Fuel economy improvements have reduced the GWP of both passenger cars and light-duty trucks by lowering the per mile emissions of carbon dioxide (CO{sub 2}). Further GWP reductions have been achieved by emission standards for criteria pollutants: carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NO{sub x}). The GWP of a criteria pollutant was calculated by multiplying the emission rate by a relative global warming factor to obtain a CO{sub 2} equivalent emission rate. Both CO{sub 2} and criteria pollutant emission rates per vehicle have decreased substantially for new light-duty vehicles over the period from 1968 to 1991. Over that period, the GWP from CO{sub 2} was reduced by almost 50% in new vehicles by improving fuel economy. In that same time period, the GWP from criteria pollutants from new vehicles was reduced with emission controls by from 80% to 90% depending on the global warming time frame of interest. Consequently, total reductions in the GWP of new passenger cars and light-duty trucks have been on the order of 55 to 75 percent compared to precontrol (before 1968) new vehicles. However, the reduction in GWP caused by emission control of criteria pollutants has been larger than the reduction caused by improved fuel economy (i.e., reduced CO{sub 2}). The contribution of criteria pollutants to the GWP of precontrol new vehicles was substantial, but their contribution has been reduced significantly due to US emission controls. As a result, the contribution of criteria pollutants to global warming is now much less than the contribution of CO{sub 2} from fuel consumption.
Reduction in global warming due to fuel economy improvements and emissions control of criteria pollutants: New US light-duty vehicles (1968--1991)

International Nuclear Information System (INIS)

Pitstick, M.E.; Santini, D.J.; Chauhan, H.

1992-01-01

This paper explores the impact of US emission controls and fuel economy improvements on the global warming potential (GWP) of new light-duty vehicles. Fuel economy improvements have reduced the GWP of both passenger cars and light-duty trucks by lowering the per mile emissions of carbon dioxide (CO 2 ). Further GWP reductions have been achieved by emission standards for criteria pollutants: carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NO x ). The GWP of a criteria pollutant was calculated by multiplying the emission rate by a relative global warming factor to obtain a CO 2 equivalent emission rate. Both CO 2 and criteria pollutant emission rates per vehicle have decreased substantially for new light-duty vehicles over the period from 1968 to 1991. Over that period, the GWP from CO 2 was reduced by almost 50% in new vehicles by improving fuel economy. In that same time period, the GWP from criteria pollutants from new vehicles was reduced with emission controls by from 80% to 90% depending on the global warming time frame of interest. Consequently, total reductions in the GWP of new passenger cars and light-duty trucks have been on the order of 55 to 75 percent compared to precontrol (before 1968) new vehicles. However, the reduction in GWP caused by emission control of criteria pollutants has been larger than the reduction caused by improved fuel economy (i.e., reduced CO 2 ). The contribution of criteria pollutants to the GWP of precontrol new vehicles was substantial, but their contribution has been reduced significantly due to US emission controls. As a result, the contribution of criteria pollutants to global warming is now much less than the contribution of CO 2 from fuel consumption

What Do They Have That We Don't Have? Local Libraries and Distance Students: Why Do Students Stray and Can We Get Them Back?

Science.gov (United States)

Behr, Michele; LaDell-Thomas, Julie

2014-01-01

A significant number of distance students report they "stray" from their home universities by using local libraries, despite the fact that distance education librarians work hard to provide customized resources and services tailored to their programs and needs. Are public libraries and special libraries able to meet the research needs of…
A Stable, Narrow-Gap Oxyfluoride Photocatalyst for Visible-Light Hydrogen Evolution and Carbon Dioxide Reduction.

Science.gov (United States)

Kuriki, Ryo; Ichibha, Tom; Hongo, Kenta; Lu, Daling; Maezono, Ryo; Kageyama, Hiroshi; Ishitani, Osamu; Oka, Kengo; Maeda, Kazuhiko

2018-05-16

Mixed anion compounds such as oxynitrides and oxychalcogenides are recognized as potential candidates of visible-light-driven photocatalysts since, as compared with oxygen 2p orbitals, p orbitals of less electronegative anion (e.g., N 3- , S 2- ) can form a valence band that has more negative potential. In this regard, oxyfluorides appear unsuitable because of the higher electronegativity of fluorine. Here we show an exceptional case, an anion-ordered pyrochlore oxyfluoride Pb 2 Ti 2 O 5.4 F 1.2 that has a small band gap (ca. 2.4 eV). With suitable modification of Pb 2 Ti 2 O 5.4 F 1.2 by promoters such as platinum nanoparticles and a binuclear ruthenium(II) complex, Pb 2 Ti 2 O 5.4 F 1.2 worked as a stable photocatalyst for visible-light-driven H 2 evolution and CO 2 reduction. Density functional theory calculations have revealed that the unprecedented visible-light-response of Pb 2 Ti 2 O 5.4 F 1.2 arises from strong interaction between Pb-6s and O-2p orbitals, which is enabled by a short Pb-O bond in the pyrochlore lattice due to the fluorine substitution.
effect of light curing unit characteristics on light intensity output

African Journals Online (AJOL)

2013-09-09

Sep 9, 2013 ... in Nairobi and their effect on light intensity output, depth of cure (DOC) and ... result in gradual reduction in the energy output of ..... of LED lights are compared with QTH lights could ... influence on the SMH of dark shades.
Residual stress characterization of steel TIG welds by neutron diffraction and by residual magnetic stray field mappings

Science.gov (United States)

Stegemann, Robert; Cabeza, Sandra; Lyamkin, Viktor; Bruno, Giovanni; Pittner, Andreas; Wimpory, Robert; Boin, Mirko; Kreutzbruck, Marc

2017-03-01

The residual stress distribution of tungsten inert gas welded S235JRC+C plates was determined by means of neutron diffraction (ND). Large longitudinal residual stresses with maxima around 600 MPa were found. With these results as reference, the evaluation of residual stress with high spatial resolution GMR (giant magneto resistance) sensors was discussed. The experiments performed indicate a correlation between changes in residual stresses (ND) and the normal component of local residual magnetic stray fields (GMR). Spatial variations in the magnetic field strength perpendicular to the welds are in the order of the magnetic field of the earth.
Inverted-conical light guide for crosstalk reduction in tightly-packed scintillator matrix and MAPMT assembly

DEFF Research Database (Denmark)

Chang, Y.-Y.; Chen, P.; Huang, J.-J.

2015-01-01

In this paper we present the Inverted-Conical light guide designed for optical crosstalk reduction in the scintillator-MAPMT assemblies. The research was motivated by the 30% crosstalk observed in UFFO X-ray telescope, UBAT, during the preliminary calibration with MAPMTs of 64 2.88 × 2.88 mm2...... pixels and identically gridded YSO crystal matrices. We began the study with the energy and crosstalk calibrations of the detector, then we constructed a GEANT4 simulation with the customized metallic film model as the MAPMT photocathode. The simulation reproduced more than 70% of the crosstalk...... and explained it as a consequence of the total reflection produced by the photocathode. The result indicated that the crosstalk mechanism could be a common case in most of the contact-assembled scintillation detectors. The concept of the Inverted-Conical light guide was to suppress the total reflection...
Source-Sink Estimates of Genetic Introgression Show Influence of Hatchery Strays on Wild Chum Salmon Populations in Prince William Sound, Alaska

OpenAIRE

Jasper, James R.; Habicht, Christopher; Moffitt, Steve; Brenner, Rich; Marsh, Jennifer; Lewis, Bert; Creelman Fox, Elisabeth; Grauvogel, Zac; Rogers Olive, Serena D.; Grant, W. Stewart

2013-01-01

The extent to which stray, hatchery-reared salmon affect wild populations is much debated. Although experiments show that artificial breeding and culture influence the genetics of hatchery salmon, little is known about the interaction between hatchery and wild salmon in a natural setting. Here, we estimated historical and contemporary genetic population structures of chum salmon (Oncorhynchus keta) in Prince William Sound (PWS), Alaska, with 135 single nucleotide polymorphism (SNP) markers. H...
Design of an ultra-thin near-eye display with geometrical waveguide and freeform optics.

Science.gov (United States)

Cheng, Dewen; Wang, Yongtian; Xu, Chen; Song, Weitao; Jin, Guofan

2014-08-25

Small thickness and light weight are two important requirements for a see-through near-eye display which are achieved in this paper by using two advanced technologies: geometrical waveguide and freeform optics. A major problem associated with the geometrical waveguide is the stray light which can severely degrade the display quality. The causes and solutions to this problem are thoroughly studied. A mathematical model of the waveguide is established and a non-sequential ray tracing algorithm is developed, which enable us to carefully examine the stray light of the planar waveguide and explore a global searching method to find an optimum design with the least amount of stray light. A projection optics using freeform surfaces on a wedge shaped prism is also designed. The near-eye display integrating the projection optics and the waveguide has a field of view of 28°, an exit pupil diameter of 9.6mm and an exit pupil distance of 20mm. In our final design, the proportion of the stray light energy over the image output energy of the waveguide is reduced to 2%, the modulation transfer function values across the entire field of the eyepiece are above 0.5 at 30 line pairs/mm (lps/mm). A proof-of-concept prototype of the proposed geometrical waveguide near-eye display is developed and demonstrated.
Magnetic analysis of the magnetic field reduction system of the ITER neutral beam injector

Energy Technology Data Exchange (ETDEWEB)

Barrera, Germán, E-mail: german.barrera@ciemat.es [CIEMAT, Laboratorio Nacional de Fusión, Avda. Complutense 22, 28040 Madrid (Spain); Ahedo, Begoña; Alonso, Javier; Ríos, Luis [CIEMAT, Laboratorio Nacional de Fusión, Avda. Complutense 22, 28040 Madrid (Spain); Chareyre, Julien; El-Ouazzani, Anass [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St Paul Lez Durance Cedex (France); Agarici, Gilbert [Fusion for Energy, Josep Pla 2, Torres Diagonal Litoral B3, 07/08, 08019 Barcelona (Spain)

2015-10-15

The neutral beam system for ITER consists of two heating and current drive neutral beam injectors (HNB) and a diagnostic neutral beam (DNB) injector. The proposed physical plant layout allows a possible third HNB injector to be installed later. For the correct operation of the beam, the ion source and the ion path until it is neutralized must operate under a very low magnetic field environment. To prevent the stray ITER field from penetrating inside those mentioned critical areas, a magnetic field reduction system (MFRS) will envelop the beam vessels and the high voltage transmission lines to ion source. This system comprises the passive magnetic shield (PMS), a box like assembly of thick low carbon steel plates, and the Active Correction and Compensation Coils (ACCC), a set of coils carrying a current which depends on the tokamak stray field. This paper describes the magnetic model and analysis results presented at the PMS and ACCC preliminary design review held in ITER organization in April 2013. The paper focuses on the magnetic model description and on the description of the analysis results. The iterative process for obtaining optimized currents in the coils is presented. The set of coils currents chosen among the many possible solutions, the magnetic field results in the interest regions and the fulfillment of the magnetic field requirements are described.
Impedance matched thin metamaterials make metals absorbing.

Science.gov (United States)

Mattiucci, N; Bloemer, M J; Aközbek, N; D'Aguanno, G

2013-11-13

Metals are generally considered good reflectors over the entire electromagnetic spectrum up to their plasma frequency. Here we demonstrate an approach to tailor their absorbing characteristics based on the effective metamaterial properties of thin, periodic metallo-dielectric multilayers by exploiting a broadband, inherently non-resonant, surface impedance matching mechanism. Based on this mechanism, we design, fabricate and test omnidirectional, thin ( 99%) over a frequency range spanning from the UV to the IR. Our approach opens new venues to design cost effective materials for many applications such as thermo-photovoltaic energy conversion devices, light harvesting for solar cells, flat panel display, infrared detectors, stray light reduction, stealth and others.
Role of visible light-activated photocatalyst on the reduction of anthrax spore-induced mortality in mice.

Directory of Open Access Journals (Sweden)

Jyh-Hwa Kau

Full Text Available BACKGROUND: Photocatalysis of titanium dioxide (TiO(2 substrates is primarily induced by ultraviolet light irradiation. Anion-doped TiO(2 substrates were shown to exhibit photocatalytic activities under visible-light illumination, relative environmentally-friendly materials. Their anti-spore activity against Bacillus anthracis, however, remains to be investigated. We evaluated these visible-light activated photocatalysts on the reduction of anthrax spore-induced pathogenesis. METHODOLOGY/PRINCIPAL FINDINGS: Standard plating method was used to determine the inactivation of anthrax spore by visible light-induced photocatalysis. Mouse models were further employed to investigate the suppressive effects of the photocatalysis on anthrax toxin- and spore-mediated mortality. We found that anti-spore activities of visible light illuminated nitrogen- or carbon-doped titania thin films significantly reduced viability of anthrax spores. Even though the spore-killing efficiency is only approximately 25%, our data indicate that spores from photocatalyzed groups but not untreated groups have a less survival rate after macrophage clearance. In addition, the photocatalysis could directly inactivate lethal toxin, the major virulence factor of B. anthracis. In agreement with these results, we found that the photocatalyzed spores have tenfold less potency to induce mortality in mice. These data suggest that the photocatalysis might injury the spores through inactivating spore components. CONCLUSION/SIGNIFICANCE: Photocatalysis induced injuries of the spores might be more important than direct killing of spores to reduce pathogenicity in the host.
Enhanced selective photocatalytic CO{sub 2} reduction into CO over Ag/CdS nanocomposites under visible light

Energy Technology Data Exchange (ETDEWEB)

Zhu, Zezhou; Qin, Jiani; Jiang, Min; Ding, Zhengxin; Hou, Yidong, E-mail: ydhou@fzu.edu.cn

2017-01-01

Highlights: • Ag/CdS nanocomposites were prepared by a facile photodeposition method. • Ag/CdS was more effective as a photocatalyst for CO{sub 2} reduction than CdS. • Ag as cocatalyst served as electron trap as well as active site for CO{sub 2} reduction reaction. - Abstract: Photocatalytic reduction of carbon dioxide can convert chemically inert carbon dioxide into useful chemical fuel in a mild manner. Herein, Ag-CdS nanocomposites were prepared by photodeposition method and examined for photocatalytic CO{sub 2} reduction under visible light. Meanwhile, the nanocomposites were characterized by XRD, SEM, TEM, XPS, DRS and PL in detail. The results show that, the deposition of Ag improves the photocatalytic performance of CdS, especially in the selectivity of CO{sub 2}-to-CO. The highest photocatalytic activity is achieved over 1.0 wt.% Ag/CdS, with an increase by 3 times in comparison to CdS. In this reaction system, Ag can serve as electron trap as well as active site for CO{sub 2} reduction, which is probably responsible for the enhanced activity and selectivity of CO{sub 2} to CO over Ag/CdS. The possible mechanism of CO{sub 2} photoreduction over Ag/CdS was proposed in view of the abovementioned analysis.
Environmental benefits from CO2 reduction, due to modal replacement: Case study on light rail vehicle in Brasilia City

Energy Technology Data Exchange (ETDEWEB)

Silva Costa, P.H. da; Alves Teixeira, L.M.; Cardoso Pinheiro, J.; Serra Arruda, F.; Mendonça Brasil, A.C.

2016-07-01

This work aims to measure the reduction of Carbon Dioxide (CO2) emissions in atmosphere by replacing the modal urban bus by Light Rail Vehicle (VLT). In order to accomplish this objective, a case study in Brasilia, Federal District, in the stretch of VLT which passes on Via W-3 South was conducted. The Theory of Externalities that discusses the right to ownership of private and public goods and responsibilities about the positive and negative externalities caused by the agents and individuals of society was used to support the analyses. It was used the Top-Down method, which allowed the calculation the direct emissions of CO2. The values obtained on the reduction of CO2 emissions were converted into values of carbon credits as a way to economically measure such reductions. The results showed a significant reduction in CO2 emissions per year and consequent environmental benefit. (Author)
Assessment of a Targeted Trap-Neuter-Return Pilot Study in Auckland, New Zealand

Science.gov (United States)

Zito, Sarah; Vigeant, Shalsee; Dale, Arnja

2018-01-01

Simple Summary It is generally accepted that stray cats need to be managed to minimise the associated negative impacts and there is a need for effective and humane management tools. One such potential tool is trap-neuter-return (TNR), which anecdotally has been used in New Zealand to manage stray cats, but no concerted and targeted implementation of this technique has been reported, nor any formal assessments conducted. A targeted TNR (TTNR) programme for urban stray cats was implemented and assessed in one Auckland suburb. Assessment was based on the number of incoming felines; stray, unsocialised cats euthanased; unsocialised, unowned cats sterilised and returned (independently of the TTNR programme); and neonatal/underage euthanasias. Incoming stray feline, underage euthanasia, and unsocialised stray cat euthanasia numbers all reduced for the targeted suburb when these outcome measures were compared for the years before and after the programme. These outcome measures had a greater reduction in the targeted suburb compared to the other Auckland suburbs not targeted by the TTNR programme, although causation cannot be inferred, as a variety of reasons could have contributed to the changes. This pilot programme suggests that TTNR could be a valuable humane cat management tool in urban New Zealand, and further assessment is warranted. Abstract There is a need for effective and humane management tools to manage urban stray cats and minimise negative impacts associated with stray cats. One such tool is targeted trap-neuter-return (TTNR), but no concerted implementation of this technique or formal assessments have been reported. To address this deficit, a TTNR programme was implemented and assessed in one Auckland suburb from May 2015 to June 2016; the programme sterilised and returned 348 cats (4.2 cats/1000 residents). Assessment was based on the number of incoming felines; stray, unsocialised cats euthanased; unsocialised, unowned cats sterilised and returned
Drag Reduction CFD Simulations and Flow Visualization of Light Vehicle-Trailer Systems

Science.gov (United States)

Sigurdson, Lorenz; Boyer, Henry; Lange, Carlos F.

2016-11-01

Experiments and CFD were performed to study the effect a deflector had on the flow and drag force associated with a 2010 F-150 truck and cargo trailer Light Vehicle-Trailer System (LVTS). Image Correlation Velocimetry (ICV) on smokewire streaklines measured the velocity field on the model mid-plane. CFD estimated the drag reduction as 13% at a Re of 14,900 with a moving ground-plane, and 17% without. Experiments suggested that the low Re does not diminish the full-scale relevance of the drag reduction results. One low Re effect was the presence of a separation bubble on the hood of the tow vehicle whose size reduced with an increase in Re. Three other characteristic flow patterns were identified: separation off the lead vehicle cab, stagnation of the free-stream on the trailer face for the no-deflector case, and subsequent separation at the trailer front corner. Comparisons of the ICV and CFD results with no deflector indicated good agreement in the direction of the velocity vectors, and the smoke streaklines and CFD streamlines also agreed well. However, for the deflector case, the CFD found an entirely different topological solution absent in the experiment. A pair of vertically-oriented mid-plane vortices were wrapped around the front of the trailer. Support from the Canadian Natural Sciences and Engineering Research Council Grant 41747 is gratefully acknowledged.
Prevalence of Toxoplasma gondii antibodies and intestinal parasites in stray cats from Nigde, Turkey

Directory of Open Access Journals (Sweden)

Bengi Dündar

2010-01-01

Full Text Available The prevalence of antibodies to Toxoplasma gondii was investigated by the Sabin-Feldman Dye test (SFDT in 72 stray cats from Nigde, Turkey. A total of 55 (76.4% of the analysed sera had antibodies to T. gondii. The seropositivity of T. gondii was 77.1% in male and 75.7% in female cats (P>0.05. Faeces of these cats were also examined by zinc sulphate flotation method for the presence of parasite oocysts and eggs of other parasites. Two protozoan parasites were identified as Isospora spp. (12.5% and Eimeria spp. (4.1% in cats. Toxoplasma gondii oocysts were not found in any faecal samples analysed. Two parasitic helminth species were observed: Toxocara cati (15.2% and Toxascaris leonina (20.8%. These common ascarids were recorded for the first time in cats from Nigde.
Catalytic role of Cu(II) in the reduction of Cr(VI) by citric acid under an irradiation of simulated solar light.

Science.gov (United States)

Li, Ying; Chen, Cheng; Zhang, Jing; Lan, Yeqing

2015-05-01

The catalytic role of Cu(II) in the reduction of Cr(VI) by citric acid with simulated solar light was investigated. The results demonstrated that Cu(II) could significantly accelerate Cr(VI) reduction and the reaction obeyed to pseudo zero-order kinetics with respect to Cr(VI). The removal of Cr(VI) was related to the initial concentrations of Cu(II), citric acid, and the types of organic acids. The optimal removal of Cr(VI) was achieved at pH 4, and the rates of Cu(II) photocatalytic reduction of Cr(VI) by organic acids were in the order: tartaric acid (two α-OH groups, two -COOH groups)>citric acid (one α-OH group, three -COOH groups)>malic acid (one α-OH group, two -COOH groups)>lactic acid (one α-OH group, one -COOH group)≫succinic acid (two -COOH groups), suggesting that the number of α-OH was the key factor for the reaction, followed by the number of -COOH. The formation of Cu(II)-citric acid complex could generate Cu(I) and radicals through a pathway of metal-ligand-electron transfer, promoting the reduction of Cr(VI). This study is helpful to fully understanding the conversion of Cr(VI) in the existence of both organic acids and Cu(II) with solar light in aquatic environments. Copyright © 2015 Elsevier Ltd. All rights reserved.
The unbearable lightness of "light" cigarettes: a comparison of smoke yields in six varieties of Canadian "light" cigarettes.

Science.gov (United States)

Gendreau, Paul L; Vitaro, Frank

2005-01-01

Labelling cigarettes as "light" or "mild" is claimed to be one of the biggest marketing scams in Canadian history. Arguably, such labelling implies that these varieties of cigarettes are less harmful than "regular" cigarettes. In Canada, a food product can be labelled "light" if there is a 25% reduction from the "reference food" and if the constituent being reduced is clearly identified (e.g., light in fat). Cigarette labelling does not comply with these regulations, however. To examine whether or not some tobacco constituents meet the 25% reduction criterion, we compared yields of 41 toxic and/or carcinogenic smoke constituents in six varieties of "light" cigarettes to the yields of "regular" cigarettes. We selected cigarettes from the two most popular Canadian brands, Du Maurier and Players. Using a set of data provided by Imperial Tobacco Canada and made available to the public by the Government of British Columbia, we compared yields measured under a laboratory protocol (modified ISO) that was designed to provide a more rigorous evaluation of the differences between varieties of cigarettes and a more accurate assessment of smokers' potential smoke intake than the traditional protocol (standard ISO). For all six varieties of "light" cigarettes, the yields of nicotine were higher by an average of 5% (range: 1% to 13%). The 25% reduction criterion was not met for any variety of "light" cigarettes concerning yields of tar. For all cigarettes tested, yields of tar were reduced on average by only 16% (range: 5% to 22%). For carbon monoxide (CO), only Player's Smooth Light had an over 25% reduction (30%) compared with Player's Regular. Conversely, yield of CO was 24% higher for Du Maurier Lights compared with Du Maurier Regular. As for the other smoke constituents, the majority (75%) were not reduced by 25% or more in "light" cigarettes, and a sizeable proportion of yields (e.g., acrylonitrile, benzene, chromium, m+p cresol, mercury, nickel, toluene) were larger in
Investigation of structure in the modular light pipe component for LED automotive lamp

Science.gov (United States)

Chen, Hsi-Chao; Zhou, Yang; Huang, Chien-Sheng; Jhong, Wan-Ling; Cheng, Bo-Wei; Jhang, Jhe-Ming

2014-09-01

Light-Emitting Diodes (LEDs) have the advantages of small length, long lifetime, fast response time (μs), low voltage, good mechanical properties and environmental protection. Furthermore, LEDs could replace the halogen lamps to avoid the mercury pollution and economize the use of energy. Therefore, the LEDs could instead of the traditional lamp in the future and became an important light source. The proposal of this study was to investigate the effects of the structure and length of the reflector component for a LED automotive lamp. The novel LED automotive lamp was assembled by several different modularization columnar. The optimized design of the different structure and the length to the reflector was simulated by software TracePro. The design result must met the vehicle regulation of United Nations Economic Commission for Europe (UNECE) such as ECE-R19 etc. The structure of the light pipe could be designed by two steps structure. Then constitute the proper structure and choose different power LED to meet the luminous intensity of the vehicle regulation. The simulation result shows the proper structure and length has the best total luminous flux and a high luminous efficiency for the system. Also, the stray light could meet the vehicle regulation of ECE R19. Finally, the experimental result of the selected structure and length of the light pipe could match the simulation result above 80%.
Inverted-conical light guide for crosstalk reduction in tightly-packed scintillator matrix and MAPMT assembly

Energy Technology Data Exchange (ETDEWEB)

Chang, Y.-Y., E-mail: gixd@hep1.phys.ntu.edu.tw [Department of Physics, National Taiwan University, 1 Roosevelt Rd., Taipei 10617, Taiwan, ROC (China); Leung Center for Cosmology and Particle Astrophysics, National Taiwan University, 1 Roosevelt Rd., Taipei 10617, Taiwan, ROC (China); Chen, C.R. [National Space Organization (NSPO), 8F., No. 9, Prosperity 1 s Rd., Hsinchu Science Park, Hsinchu 30078, Taiwan, ROC (China); Chen, P.; Huang, J.-J. [Department of Physics, National Taiwan University, 1 Roosevelt Rd., Taipei 10617, Taiwan, ROC (China); Leung Center for Cosmology and Particle Astrophysics, National Taiwan University, 1 Roosevelt Rd., Taipei 10617, Taiwan, ROC (China); Huang, M.A. [Leung Center for Cosmology and Particle Astrophysics, National Taiwan University, 1 Roosevelt Rd., Taipei 10617, Taiwan, ROC (China); Department of Energy Engineering, National United University, 1, Lienda, Miaoli 36003, Taiwan, ROC (China); Liu, T.-C. [Leung Center for Cosmology and Particle Astrophysics, National Taiwan University, 1 Roosevelt Rd., Taipei 10617, Taiwan, ROC (China); Nam, J.W. [Department of Physics, National Taiwan University, 1 Roosevelt Rd., Taipei 10617, Taiwan, ROC (China); Leung Center for Cosmology and Particle Astrophysics, National Taiwan University, 1 Roosevelt Rd., Taipei 10617, Taiwan, ROC (China); Wang, M.-Z., E-mail: mzwang@hep1.phys.ntu.edu.tw [Department of Physics, National Taiwan University, 1 Roosevelt Rd., Taipei 10617, Taiwan, ROC (China); Leung Center for Cosmology and Particle Astrophysics, National Taiwan University, 1 Roosevelt Rd., Taipei 10617, Taiwan, ROC (China); Bogomolov, V. [Skobeltsyn Institute of Nuclear Physics of Lomonosov Moscow State University, Leninskie Gory 119234 (Russian Federation); Physics Department of Lomonosov Moscow State University, Leninskie Gory 119234 (Russian Federation); Brandt, S.; Budtz-Jørgensen, C. [National Space Institute, Astrophysics, Technical University of Denmark, DK-2800 Kongens, Lyngby (Denmark); and others

2015-01-21

In this paper we present the Inverted-Conical light guide designed for optical crosstalk reduction in the scintillator-MAPMT assemblies. The research was motivated by the 30% crosstalk observed in UFFO X-ray telescope, UBAT, during the preliminary calibration with MAPMTs of 64 2.88×2.88 mm{sup 2} pixels and identically gridded YSO crystal matrices. We began the study with the energy and crosstalk calibrations of the detector, then we constructed a GEANT4 simulation with the customized metallic film model as the MAPMT photocathode. The simulation reproduced more than 70% of the crosstalk and explained it as a consequence of the total reflection produced by the photocathode. The result indicated that the crosstalk mechanism could be a common case in most of the contact-assembled scintillation detectors. The concept of the Inverted-Conical light guide was to suppress the total reflection by contracting the incident angle of the scintillation. We optimized the design in the simulation and fabricated a test sample. The test sample reduced 52% crosstalk with a loss of 6% signal yield. The idea of the Inverted-Conical light guide can be adapted by scintillation detectors multi-pixel, imaging-purpose scintillation detectors such as the ultra-fast GRB observatory UFFO-UBAT, whose performances are sensitive to responding time, image resolution, and geometrical modifications.
Inverted-conical light guide for crosstalk reduction in tightly-packed scintillator matrix and MAPMT assembly

International Nuclear Information System (INIS)

Chang, Y.-Y.; Chen, C.R.; Chen, P.; Huang, J.-J.; Huang, M.A.; Liu, T.-C.; Nam, J.W.; Wang, M.-Z.; Bogomolov, V.; Brandt, S.; Budtz-Jørgensen, C.

2015-01-01

In this paper we present the Inverted-Conical light guide designed for optical crosstalk reduction in the scintillator-MAPMT assemblies. The research was motivated by the 30% crosstalk observed in UFFO X-ray telescope, UBAT, during the preliminary calibration with MAPMTs of 64 2.88×2.88 mm 2 pixels and identically gridded YSO crystal matrices. We began the study with the energy and crosstalk calibrations of the detector, then we constructed a GEANT4 simulation with the customized metallic film model as the MAPMT photocathode. The simulation reproduced more than 70% of the crosstalk and explained it as a consequence of the total reflection produced by the photocathode. The result indicated that the crosstalk mechanism could be a common case in most of the contact-assembled scintillation detectors. The concept of the Inverted-Conical light guide was to suppress the total reflection by contracting the incident angle of the scintillation. We optimized the design in the simulation and fabricated a test sample. The test sample reduced 52% crosstalk with a loss of 6% signal yield. The idea of the Inverted-Conical light guide can be adapted by scintillation detectors multi-pixel, imaging-purpose scintillation detectors such as the ultra-fast GRB observatory UFFO-UBAT, whose performances are sensitive to responding time, image resolution, and geometrical modifications

Reductive Umpolung of Carbonyl Derivatives with Visible-Light Photoredox Catalysis: Direct Access to Vicinal Diamines and Amino Alcohols via α-Amino Radicals and Ketyl Radicals

KAUST Repository

Fava, Eleonora; Millet, Anthony; Nakajima, Masaki; Loescher, Sebastian; Rueping, Magnus

2016-01-01

Visible-light-mediated photoredox-catalyzed aldimine-aniline and aldehyde-aniline couplings have been realized. The reductive single electron transfer (SET) umpolung of various carbonyl derivatives enabled the generation of intermediary ketyl and α-amino radical anions, which were utilized for the synthesis of unsymmetrically substituted 1,2-diamines and amino alcohols. Anilines can be coupled with aldimines or aldehydes in a visible-light-mediated photoredox-catalyzed process. Reductive single electron transfer (SET) umpolung of the carbonyl derivatives leads to the generation of intermediary ketyl and α-amino radical anions, which were used for the synthesis of unsymmetrically substituted 1,2-diamines and amino alcohols.
Reductive Umpolung of Carbonyl Derivatives with Visible-Light Photoredox Catalysis: Direct Access to Vicinal Diamines and Amino Alcohols via α-Amino Radicals and Ketyl Radicals

KAUST Repository

Fava, Eleonora

2016-05-02

Visible-light-mediated photoredox-catalyzed aldimine-aniline and aldehyde-aniline couplings have been realized. The reductive single electron transfer (SET) umpolung of various carbonyl derivatives enabled the generation of intermediary ketyl and α-amino radical anions, which were utilized for the synthesis of unsymmetrically substituted 1,2-diamines and amino alcohols. Anilines can be coupled with aldimines or aldehydes in a visible-light-mediated photoredox-catalyzed process. Reductive single electron transfer (SET) umpolung of the carbonyl derivatives leads to the generation of intermediary ketyl and α-amino radical anions, which were used for the synthesis of unsymmetrically substituted 1,2-diamines and amino alcohols.
Scaled-model guidelines for formation-flying solar coronagraph missions.

Science.gov (United States)

Landini, Federico; Romoli, Marco; Baccani, Cristian; Focardi, Mauro; Pancrazzi, Maurizio; Galano, Damien; Kirschner, Volker

2016-02-15

Stray light suppression is the main concern in designing a solar coronagraph. The main contribution to the stray light for an externally occulted space-borne solar coronagraph is the light diffracted by the occulter and scattered by the optics. It is mandatory to carefully evaluate the diffraction generated by an external occulter and the impact that it has on the stray light signal on the focal plane. The scientific need for observations to cover a large portion of the heliosphere with an inner field of view as close as possible to the photospheric limb supports the ambition of launching formation-flying giant solar coronagraphs. Their dimension prevents the possibility of replicating the flight geometry in a clean laboratory environment, and the strong need for a scaled model is thus envisaged. The problem of scaling a coronagraph has already been faced for exoplanets, for a single point source on axis at infinity. We face the problem here by adopting an original approach and by introducing the scaling of the solar disk as an extended source.
Reduction in biomass burning aerosol light absorption upon humidification: roles of inorganically-induced hygroscopicity, particle collapse, and photoacoustic heat and mass transfer

Science.gov (United States)

Lewis, K. A.; Arnott, W. P.; Moosmüller, H.; Chakrabarty, R. K.; Carrico, C. M.; Kreidenweis, S. M.; Day, D. E.; Malm, W. C.; Laskin, A.; Jimenez, J. L.; Ulbrich, I. M.; Huffman, J. A.; Onasch, T. B.; Trimborn, A.; Liu, L.; Mishchenko, M. I.

2009-11-01

Smoke particle emissions from the combustion of biomass fuels typical for the western and southeastern United States were studied and compared under high humidity and ambient conditions in the laboratory. The fuels used were Montana ponderosa pine (Pinus ponderosa), southern California chamise (Adenostoma fasciculatum), and Florida saw palmetto (Serenoa repens). Information on the non-refractory chemical composition of biomass burning aerosol from each fuel was obtained with an aerosol mass spectrometer and through estimation of the black carbon concentration from light absorption measurements at 870 nm. Changes in the optical and physical particle properties under high humidity conditions were observed for hygroscopic smoke particles containing substantial inorganic mass fractions that were emitted from combustion of chamise and palmetto fuels. Light scattering cross sections increased under high humidity for these particles, consistent with the hygroscopic growth measured for 100 nm particles in HTDMA measurements. Photoacoustic measurements of aerosol light absorption coefficients revealed a 20% reduction with increasing relative humidity, contrary to the expectation of light absorption enhancement by the liquid coating taken up by hygroscopic particles. This reduction is hypothesized to arise from two mechanisms: (1) shielding of inner monomers after particle consolidation or collapse with water uptake; (2) the lower case contribution of mass transfer through evaporation and condensation at high relative humidity (RH) to the usual heat transfer pathway for energy release by laser-heated particles in the photoacoustic measurement of aerosol light absorption. The mass transfer contribution is used to evaluate the fraction of aerosol surface covered with liquid water solution as a function of RH.
Reduction in biomass burning aerosol light absorption upon humidification: Roles of inorganically-induced hygroscopicity, particle collapse, and photoacoustic heat and mass transfer

Energy Technology Data Exchange (ETDEWEB)

lewis, Kristen A.; Arnott, W. P.; Moosmuller, H.; Chakrabarti, Raj; Carrico, Christian M.; Kreidenweis, Sonia M.; Day, Derek E.; Malm, William C.; Laskin, Alexander; Jimenez, Jose L.; Ulbrich, Ingrid M.; Huffman, John A.; Onasch, Timothy B.; Trimborn, Achim; Liu, Li; Mishchenko, M.

2009-11-27

Smoke particle emissions from the combustion of biomass fuels typical for the western and southeastern United States were studied and compared under high humidity and ambient conditions in the laboratory. The fuels used are Montana ponderosa pine (Pinus ponderosa), southern California chamise (Adenostoma fasciculatum), and Florida saw palmetto (Serenoa repens). Information on the non-refractory chemical composition of biomass burning aerosol from each fuel was obtained with an aerosol mass spectrometer and through estimation of the black carbon concentration from light absorption measurements at 870 nm. Changes in the optical and physical particle properties under high humidity conditions were observed for hygroscopic smoke particles containing substantial inorganic mass fractions that were emitted from combustion of chamise and palmetto fuels. Light scattering cross sections increased under high humidity for these particles, consistent with the hygroscopic growth measured for 100 nm particles in HTDMA measurements. Photoacoustic measurements of aerosol light absorption coefficients reveal a 20% reduction with increasing relative humidity, contrary to the expectation of light absorption enhancement by the liquid coating taken up by hygroscopic particles. This reduction is hypothesized to arise from two mechanisms: 1. Shielding of inner monomers after particle consolidation or collapse with water uptake; 2. The contribution of mass transfer through evaporation and condensation at high relative humidity to the usual heat transfer pathway for energy release by laser heated particles in the photoacoustic measurement of aerosol light absorption. The mass transfer contribution is used to evaluate the fraction of aerosol surface covered with liquid water solution as a function of RH.
Modelling the behaviour of the push-pull gel dosimeter

International Nuclear Information System (INIS)

Bosi, S.G.; Davies, J.B.; Gorjiara, T.; Baldock, C.

2010-01-01

Full text: Recent development of a gel dosimeter based on the radiobleaching pigment, genipin, allows development of a new 3D optically scanned gel dosimeter-the p ush-pull g el. This gel would contain two spectrally complementary pigments, one which darkens with dose and another (e.g. genipin) which bleaches. The two pigments deal separately with the high and low dose ends of the dosimeter's dynamic range. The bleaching pigment would be optimised for high sensitivity and the darkening pigment for low. Employing dual pigments, optimised independently, relaxes the need for compromise between sensitivity at low dose and accuracy at high dose. Such a gel, after exposure, would be read using two successive optical CT scans, at two different wavelengths. The reduction in sensitivity of the darkening pigment (allowed by the use of push-pull) would reduce the occurrence of regions of high optical attenuation which can generate optical CT artefacts. Simulated optical CT reconstructions of the optical density map (Fig. La) scanned at the darkening pigment wavelength of a hypothetical push-pull gel, confirms the reduction in susceptibility to artefacts. Fig. I b shows a profile through the map with no stray light added. The centre of the profile in Fig. I d shows a cupping artefact produced by 10 ppm of stray light. The similarity of Fig. Ic and b show that a 30% sensitivity reduction allowed by push-pull, renders the artefact negligible. This paper presents the results of' these simulations of a push-pull gel scanned using optical CT and also some results of experiments with genipin gel. (author)
Reduction of releases of radioactive effluents from light-water-power-reactors in Japan

International Nuclear Information System (INIS)

Yoshida, Y.; Itakura, T.; Kanai, T.

1977-01-01

Japan Atomic Energy Commission established the dose objectives to the population around the light-water-reactors in May, 1975, based on the ''ALAP'' concept. These values are respectively, 5 mrems per year for total body and 15 mrems per year for thyroid of an individual in the critical group in the environs, due to both gaseous and liquid effluents from LWRs in one site. The present paper describes the implications of the dose objective values, control measures which have been adopted to reduce releases of radioactive materials and related technical developments in Japan. The main control measures for reduction of radioactive gaseous effluents are an installation of a charcoal gas holdup system for decay of noble gases and a supply of clean steam for the gland seal of a turbine in BWR, and a storage tank system allowing decay of noble gases in PWR. For liquid effluents are taken measures to re-use them as the primary coolant. Consequently, the amounts of radioactivity released to the environment from any LWR during normal operation have been maintained under the level to meet the above dose objective values. For research reactors, reduction of release of effluents has also been carried out in a similar way to LWRs. In order to establish the techniques applicable for further reduction, studies are being made on the control measures to reduce leakage of radioiodine, an apparatus for removal of krypton, the treatment of laundry waste and measures to remove the crud in the primary coolant. Presentation is also made on the energy-integrated gas monitor for gaseous effluent and systems of measuring γ dose from radioactive cloud descriminating from natural background, which have been developed for effective monitoring thus reduced environmental dose
Specific feature of magnetooptical images of stray fields of magnets of various geometrical shapes

Science.gov (United States)

Ivanov, V. E.; Koveshnikov, A. V.; Andreev, S. V.

2017-08-01

Specific features of magnetooptical images (MOIs) of stray fields near the faces of prismatic hard magnetic elements have been studied. Attention has primarily been focused on MOIs of fields near faces oriented perpendicular to the magnetic moment of hard magnetic elements. With regard to the polar sensitivity, MOIs have practically uniform brightness and geometrically they coincide with the figures of the bases of the elements. With regard to longitudinal sensitivity, MOIs consist of several sectors, the number of which is determined by the number of angles of the image. Each angle is divided by the bisectrix into two sectors of different brightnesses; therefore, the MOI of a triangular magnet consists of three sectors. A rectangle consists of four sectors separated by the bisectrices of the interior angles. In all types of figures, these lines converge at the center of the figure and form a singular point of the source or sink type.
Light-absorbing impurities enhance glacier albedo reduction in the southeastern Tibetan plateau

Science.gov (United States)

Zhang, Yulan; Kang, Shichang; Cong, Zhiyuan; Schmale, Julia; Sprenger, Michael; Li, Chaoliu; Yang, Wei; Gao, Tanguang; Sillanpää, Mika; Li, Xiaofei; Liu, Yajun; Chen, Pengfei; Zhang, Xuelei

2017-07-01

Light-absorbing impurities (LAIs) in snow of the southeastern Tibetan Plateau (TP) and their climatic impacts are of interest not only because this region borders areas affected by the South Asian atmospheric brown clouds but also because the seasonal snow and glacier melt from this region form important headwaters of large rivers. In this study, we collected surface snow and snowpit samples from four glaciers in the southeastern TP in June 2015 to investigate the comprehensive observational data set of LAIs. Results showed that the LAI concentrations were much higher in the aged snow and granular ice than in the fresh snow and snowpits due to postdepositional processes. Impurity concentrations fluctuated across snowpits, with maximum LAI concentrations frequently occurring toward the bottom of snowpits. Based on the SNow ICe Aerosol Radiative model, the albedo simulation indicated that black carbon and dust account for approximately 20% of the albedo reduction relative to clean snow. The radiative forcing caused by black carbon and dust deposition on the glaciers were between 1.0-141 W m-2 and 1.5-120 W m-2, respectively. Black carbon (BC) played a larger role in albedo reduction and radiative forcing than dust in the study area, enhancing approximately 15% of glacier melt. Analysis based on the Fire INventory from NCAR indicated that nonbiomass-burning sources of BC played an important role in the total BC deposition, especially during the monsoon season. This study suggests that eliminating anthropogenic BC could mitigate glacier melt in the future of the southeastern TP.
Source-sink estimates of genetic introgression show influence of hatchery strays on wild chum salmon populations in Prince William Sound, Alaska.

Directory of Open Access Journals (Sweden)

James R Jasper

Full Text Available The extent to which stray, hatchery-reared salmon affect wild populations is much debated. Although experiments show that artificial breeding and culture influence the genetics of hatchery salmon, little is known about the interaction between hatchery and wild salmon in a natural setting. Here, we estimated historical and contemporary genetic population structures of chum salmon (Oncorhynchus keta in Prince William Sound (PWS, Alaska, with 135 single nucleotide polymorphism (SNP markers. Historical population structure was inferred from the analysis of DNA from fish scales, which had been archived since the late 1960's for several populations in PWS. Parallel analyses with microsatellites and a test based on Hardy-Weinberg proportions showed that about 50% of the fish-scale DNA was cross-contaminated with DNA from other fish. These samples were removed from the analysis. We used a novel application of the classical source-sink model to compare SNP allele frequencies in these archived fish-scales (1964-1982 with frequencies in contemporary samples (2008-2010 and found a temporal shift toward hatchery allele frequencies in some wild populations. Other populations showed markedly less introgression, despite moderate amounts of hatchery straying. The extent of introgression may reflect similarities in spawning time and life-history traits between hatchery and wild fish, or the degree that hybrids return to a natal spawning area. The source-sink model is a powerful means of detecting low levels of introgression over several generations.
Reduction in biomass burning aerosol light absorption upon humidification: roles of inorganically-induced hygroscopicity, particle collapse, and photoacoustic heat and mass transfer

Directory of Open Access Journals (Sweden)

L. Liu

2009-11-01

Full Text Available Smoke particle emissions from the combustion of biomass fuels typical for the western and southeastern United States were studied and compared under high humidity and ambient conditions in the laboratory. The fuels used were Montana ponderosa pine (Pinus ponderosa, southern California chamise (Adenostoma fasciculatum, and Florida saw palmetto (Serenoa repens. Information on the non-refractory chemical composition of biomass burning aerosol from each fuel was obtained with an aerosol mass spectrometer and through estimation of the black carbon concentration from light absorption measurements at 870 nm. Changes in the optical and physical particle properties under high humidity conditions were observed for hygroscopic smoke particles containing substantial inorganic mass fractions that were emitted from combustion of chamise and palmetto fuels. Light scattering cross sections increased under high humidity for these particles, consistent with the hygroscopic growth measured for 100 nm particles in HTDMA measurements. Photoacoustic measurements of aerosol light absorption coefficients revealed a 20% reduction with increasing relative humidity, contrary to the expectation of light absorption enhancement by the liquid coating taken up by hygroscopic particles. This reduction is hypothesized to arise from two mechanisms: (1 shielding of inner monomers after particle consolidation or collapse with water uptake; (2 the lower case contribution of mass transfer through evaporation and condensation at high relative humidity (RH to the usual heat transfer pathway for energy release by laser-heated particles in the photoacoustic measurement of aerosol light absorption. The mass transfer contribution is used to evaluate the fraction of aerosol surface covered with liquid water solution as a function of RH.
Double-grating polychromator for laser-aided plasma diagnostics

International Nuclear Information System (INIS)

Mukhin, E.E.; Razdobarin, G.T.; Semenov, V.V.; Shilnikov, A.N.; Sukhanov, V.L.; Tolstjakov, S.Yu.; Kochergin, M.M.; Mihailovskij, Yu.K.; Bakh, L.I.

2004-01-01

A wide bandpass double-grating polychromator with high rejection and high transmission has been designed and manufactured for laser-aided plasma diagnostics. The special mount utilizes subtractive dispersion in the second stage of the double polychromator such that the larger dispersion of the second stage is reduced by that of the first stage. This affects the intensity of the stray light background at the laser wavelength. The background at the edge of the laser line was measured at 10 -5 of the light incident on the input slit. At the short end of the 200 nm bandpass, the stray light relative intensity approached 10 -7
Neutron measurements in the stray field produced by 158 GeV/c lead ion beams

International Nuclear Information System (INIS)

Agosteo, S.; Birattari, C.; Foglio Para, A.; Nava, E.; Silari, M.; Ulrici, L.

1997-01-01

This paper discusses measurements carried out at CERN in the stray radiation field produced by 158 GeV/c 208 Pb 82+ ions. The purpose was to test and intercompare the response of several detectors, mainly neutron measuring devices, and to determine the neutron spectral fluence as well as the microdosimetric (absorbed dose and dose equivalent) distributions in different locations around the shielding. Both active instruments and passive dosimeters were employed, including different types of Andersson-Braun rem counters, a tissue equivalent proportional counter, a set of superheated drop detectors, a Bonner sphere system and different types of ion chambers. Activation measurements with 12 C plastic scintillators and with 32 S pellets were also performed to assess the neutron yield of high energy lead ions interacting with a thin gold target. The results are compared with previous measurements and with measurements made during proton runs. (author)
LightSavers : accelerating advanced outdoor lighting

Energy Technology Data Exchange (ETDEWEB)

Purcell, B.; Pickering, M.

2010-01-15

This paper provided an update to the Toronto Atmospheric Fund (TAF) LightSavers program. The program was designed to accelerate market transformation for light emitting diode (LED) and advanced lighting management systems in outdoor lighting applications. It is expected that the program will result in significant electricity savings and emissions reductions within the Greater Toronto Area (GTA) and other Ontario municipalities. The first phase of the program established advanced outdoor lighting pilot programs in parking lots, garages, and pathway lighting applications that were guided by a common monitoring protocol to ensure useful and reliable assessment of the pilot programs. The TAF has since developed a strategy to strengthen public understanding and support for the use of advanced lighting, and continues to address policy issues that may impact the future of LED lighting programs. The TAF has also activated an electronic newsletter, delivered public workshops, and has been represented at several conferences. A working partnership has been established with Toronto Hydro Energy Services. Five pilot sites have been installed and have begun to provide monitoring data. Details of the pilot programs were provided. 16 figs.
Renewable Molecular Flasks with NADH Models: Combination of Light-Driven Proton Reduction and Biomimetic Hydrogenation of Benzoxazinones.

Science.gov (United States)

Zhao, Liang; Wei, Jianwei; Lu, Junhua; He, Cheng; Duan, Chunying

2017-07-17

Using small molecules with defined pockets to catalyze chemical transformations resulted in attractive catalytic syntheses that echo the remarkable properties of enzymes. By modulating the active site of a nicotinamide adenine dinucleotide (NADH) model in a redox-active molecular flask, we combined biomimetic hydrogenation with in situ regeneration of the active site in a one-pot transformation using light as a clean energy source. This molecular flask facilitates the encapsulation of benzoxazinones for biomimetic hydrogenation of the substrates within the inner space of the flask using the active sites of the NADH models. The redox-active metal centers provide an active hydrogen source by light-driven proton reduction outside the pocket, allowing the in situ regeneration of the NADH models under irradiation. This new synthetic platform, which offers control over the location of the redox events, provides a regenerating system that exhibits high selectivity and efficiency and is extendable to benzoxazinone and quinoxalinone systems. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
THE EFFELSBERG-BONN H I SURVEY: DATA REDUCTION

International Nuclear Information System (INIS)

Winkel, B.; Kalberla, P. M. W.; Kerp, J.; Floeer, L.

2010-01-01

Starting in winter 2008/2009 an L-band seven-feed-array receiver is used for a 21 cm line survey performed with the 100 m telescope, the Effelsberg-Bonn H I survey (EBHIS). The EBHIS will cover the whole northern hemisphere for decl. > - 5 0 comprising both the galactic and extragalactic sky out to a distance of about 230 Mpc. Using state-of-the-art FPGA-based digital fast Fourier transform spectrometers, superior in dynamic range and temporal resolution to conventional correlators, allows us to apply sophisticated radio frequency interference (RFI) mitigation schemes. In this paper, the EBHIS data reduction package and first results are presented. The reduction software consists of RFI detection schemes, flux and gain-curve calibration, stray-radiation removal, baseline fitting, and finally the gridding to produce data cubes. The whole software chain is successfully tested using multi-feed data toward many smaller test fields (1-100 deg 2 ) and recently applied for the first time to data of two large sky areas, each covering about 2000 deg 2 . The first large area is toward the northern galactic pole and the second one toward the northern tip of the Magellanic Leading Arm. Here, we demonstrate the data quality of EBHIS Milky Way data and give a first impression on the first data release in 2011.
Analysis of the accuracy of different laboratory methods for the diagnosis of intestinal parasites from stray and domiciled cats (Felis catus domesticus in Goiânia, Goiás, Brazil

Directory of Open Access Journals (Sweden)

Jaqueline Ataíde Silva Lima

2018-02-01

Full Text Available Abstract Cats are carriers of zoonotic agents to humans, including intestinal parasites. The purpose of this study was to analyze the accuracy of different laboratory methods for the diagnosis of intestinal parasites. Fecal samples were processed by the Willis, Sheather, Faust and Hoffman-Janer-Pons-Lutz (HJPL methods. Accuracy analysis was performed determining the sensitivity, specificity, positive and negative predictive value and Kappa. A total of 149 fecal samples were collected, 65 from stray cats and 84 from domiciled cats. The prevalence of intestinal parasites in stray cats was 60% while in domiciled cats it was 17%. In the analysis of accuracy, the techniques that showed the greatest accuracy for Ancylostomids were Willis and Faust, for Cystoisospora spp. Sheather with Faust or HPJL, and Toxoplasma gondii/Hammondia hammondi the association between Willis and Faust. Therefore, for a reliable evaluation of the prevalence of intestinal parasites, at least two different techniques should be used in parasitological exams of feces.
Light output from six battery operated dental curing lights

Energy Technology Data Exchange (ETDEWEB)

Shimokawa, Carlos Alberto Kenji, E-mail: carlos.shimokawa@usp.br [University of São Paulo, School of Dentistry, Restorative Dentistry, Avenida Professor Lineu Prestes, 2227, 05508-000, São Paulo, São Paulo (Brazil); Dalhousie University, Faculty of Dentistry, Dental Clinical Sciences, 5981 University Avenue, B3H 4R2, Halifax, Nova Scotia (Canada); Turbino, Míriam Lacalle, E-mail: miturbin@usp.br [University of São Paulo, School of Dentistry, Restorative Dentistry, Avenida Professor Lineu Prestes, 2227, 05508-000, São Paulo, São Paulo (Brazil); Harlow, Jessie Eudora, E-mail: jessie.harlow@dal.ca [Dalhousie University, Faculty of Dentistry, Dental Clinical Sciences, 5981 University Avenue, B3H 4R2, Halifax, Nova Scotia (Canada); Price, Hannah Louise, E-mail: hannlprice@gmail.com [Dalhousie University, Faculty of Dentistry, Dental Clinical Sciences, 5981 University Avenue, B3H 4R2, Halifax, Nova Scotia (Canada); Price, Richard Bengt, E-mail: richard.price@dal.ca [Dalhousie University, School of Biomedical Engineering and Faculty of Dentistry, 5981 University Avenue, B3H 4R2, Halifax, Nova Scotia (Canada)

2016-12-01

Light Curing Units (LCUs) are used daily in almost every dental office to photocure resins, but because the light is so bright, the user is unable to tell visually if there are any differences between different LCUs. This study evaluated the light output from six dental LCUs: Elipar Deep Cure-S (3M ESPE), Bluephase G2 (Ivoclar Vivadent), Translux 2Wave (Heraeus Kulzer), Optilight Prime (Gnatus), Slim Blast (First Medica) and Led.B (Guilin Woodpecker) with a fully charged battery, after 50, and again after 100, 20 second light exposures. For each situation, the radiant power was measured 10 times with a laboratory-grade power meter. Then, the emission spectrum was measured using a fiber-optic spectrometer followed by an analysis of the light beam profile. It was found there were significant differences in the LCU power and the irradiance values between the LCUs (p < 0.01). The Optilight Prime and Slim Blast LCUs showed a significant reduction in light output after a 50 and 100 exposures, while Bluephase G2 exhibited a significant reduction only after 100 exposures (p < 0.01). The Bluephase G2 and Translux 2 Wave delivered an emission spectrum that had two distinct wavelength emission peaks. Only the Elipar Deep Cure-S and Bluephase G2 LCUs displayed homogeneous light beam profiles, the other LCUs exhibited highly non-homogeneous light beam profiles. It was concluded that contemporary LCUs could have very different light output characteristics. Both manufacturers and researchers should provide more information about the light output from LCUs. - Highlights: • The six LCUs delivered significantly different light output characteristics. • The use of a single irradiance value does not adequately describe the light output from a curing light. • Small differences in the tip area, or how it is defined, will have a large effect on the calculated irradiance. • In some cases there were large portions of the light tip that emitted less than 400 mW/cm². • The radiant
Light output from six battery operated dental curing lights

International Nuclear Information System (INIS)

Shimokawa, Carlos Alberto Kenji; Turbino, Míriam Lacalle; Harlow, Jessie Eudora; Price, Hannah Louise; Price, Richard Bengt

2016-01-01

Light Curing Units (LCUs) are used daily in almost every dental office to photocure resins, but because the light is so bright, the user is unable to tell visually if there are any differences between different LCUs. This study evaluated the light output from six dental LCUs: Elipar Deep Cure-S (3M ESPE), Bluephase G2 (Ivoclar Vivadent), Translux 2Wave (Heraeus Kulzer), Optilight Prime (Gnatus), Slim Blast (First Medica) and Led.B (Guilin Woodpecker) with a fully charged battery, after 50, and again after 100, 20 second light exposures. For each situation, the radiant power was measured 10 times with a laboratory-grade power meter. Then, the emission spectrum was measured using a fiber-optic spectrometer followed by an analysis of the light beam profile. It was found there were significant differences in the LCU power and the irradiance values between the LCUs (p < 0.01). The Optilight Prime and Slim Blast LCUs showed a significant reduction in light output after a 50 and 100 exposures, while Bluephase G2 exhibited a significant reduction only after 100 exposures (p < 0.01). The Bluephase G2 and Translux 2 Wave delivered an emission spectrum that had two distinct wavelength emission peaks. Only the Elipar Deep Cure-S and Bluephase G2 LCUs displayed homogeneous light beam profiles, the other LCUs exhibited highly non-homogeneous light beam profiles. It was concluded that contemporary LCUs could have very different light output characteristics. Both manufacturers and researchers should provide more information about the light output from LCUs. - Highlights: • The six LCUs delivered significantly different light output characteristics. • The use of a single irradiance value does not adequately describe the light output from a curing light. • Small differences in the tip area, or how it is defined, will have a large effect on the calculated irradiance. • In some cases there were large portions of the light tip that emitted less than 400 mW/cm². • The radiant
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.

Selective catalyst reduction light-off strategy

Science.gov (United States)

Gonze, Eugene V [Pinckney, MI

2011-10-18

An emissions control system includes a temperature determination module and an emissions control module. The temperature determination module determines a first temperature of a heater element of a diesel particulate filter (DPF) assembly in an exhaust system and determines a second temperature of a catalyst of the DPF assembly. The emissions control module selectively activates the heater element, selectively initiates a predefined combustion process in an engine based upon the first temperature, and selectively starts a reductant injection process based upon the second temperature.
A simple and fast physics-based analytical method to calculate therapeutic and stray doses from external beam, megavoltage x-ray therapy.

Science.gov (United States)

Jagetic, Lydia J; Newhauser, Wayne D

2015-06-21

State-of-the-art radiotherapy treatment planning systems provide reliable estimates of the therapeutic radiation but are known to underestimate or neglect the stray radiation exposures. Most commonly, stray radiation exposures are reconstructed using empirical formulas or lookup tables. The purpose of this study was to develop the basic physics of a model capable of calculating the total absorbed dose both inside and outside of the therapeutic radiation beam for external beam photon therapy. The model was developed using measurements of total absorbed dose in a water-box phantom from a 6 MV medical linear accelerator to calculate dose profiles in both the in-plane and cross-plane direction for a variety of square field sizes and depths in water. The water-box phantom facilitated development of the basic physical aspects of the model. RMS discrepancies between measured and calculated total absorbed dose values in water were less than 9.3% for all fields studied. Computation times for 10 million dose points within a homogeneous phantom were approximately 4 min. These results suggest that the basic physics of the model are sufficiently simple, fast, and accurate to serve as a foundation for a variety of clinical and research applications, some of which may require that the model be extended or simplified based on the needs of the user. A potentially important advantage of a physics-based approach is that the model is more readily adaptable to a wide variety of treatment units and treatment techniques than with empirical models.
Analysis of stray grain formation in single crystal CMSX-4 superalloy; Analyse der Bildung von Fehlkoernern in einer einkristallinen CMSX-4-Superlegierung

Energy Technology Data Exchange (ETDEWEB)

Chmiela, Bartosz; Sozanska, Maria; Cwajna, Jan [Silesian Univ. of Technology, Katowice (Poland). Dept. of Materials Science; Szeliga, Dariusz [Rzeszow Univ. of Technology (Poland). Dept. of Materials Science; Jarczyk, Jerzy [ALD Vacuum Technologies, Hanau (Germany)

2013-08-01

Modern single crystal (SX) turbine blades are fabricated by directional solidification using a grain selector. The grain selection process was investigated by numerical simulation and verified by the experiment. A coupled ProCAST and cellular automaton finite element (CAFE) model was used in this study. According to the latest literature data, we designed the grain selector. Simulation confirmed an optimal grain selection efficiency of the applied selector geometry. The obtained experimental results reveal the possibility of stray grain formation in SX castings with a designed selector, in contrast to the simulation results. (orig.)
Indwelling Stent Embedded with Light-Emitting Diodes for Photodynamic Therapy of Malignant Biliary Obstruction

International Nuclear Information System (INIS)

Baran, Timothy M.; Mironov, Oleg; Sharma, Ashwani K.; Foster, Thomas H.

2016-01-01

PurposeWe describe the design and preliminary characterization of a stent incorporating light-emitting diodes (LEDs) for photodynamic therapy (PDT) of malignant biliary obstruction.MethodsA prototype was constructed with red (640 nm) LEDs embedded in a 14.5 French polyurethane tube. The device was evaluated for optical power and subjected to physical and electrical tests. PDT-induced reactive oxygen species were imaged in a gel phantom.ResultsThe stent functioned at a 2.5-cm bend radius and illuminated for 6 months in saline. No stray currents were detected, and it was cool after 30 minutes of operation. Optical power of 5–15 mW is applicable to PDT. Imaging of a reactive oxygen indicator showed LED-stent activation of photosensitizer.ConclusionsThe results motivate biological testing and design optimization.
Indwelling Stent Embedded with Light-Emitting Diodes for Photodynamic Therapy of Malignant Biliary Obstruction

Energy Technology Data Exchange (ETDEWEB)

Baran, Timothy M., E-mail: timothy.baran@rochester.edu [University of Rochester Medical Center, Department of Imaging Sciences (United States); Mironov, Oleg, E-mail: oleg.mironov@uhn.ca [University Health Network, The Joint Department of Medical Imaging (Canada); Sharma, Ashwani K., E-mail: Ashwani-Sharma@URMC.Rochester.edu; Foster, Thomas H., E-mail: thomas.foster@rochester.edu [University of Rochester Medical Center, Department of Imaging Sciences (United States)

2016-06-15

PurposeWe describe the design and preliminary characterization of a stent incorporating light-emitting diodes (LEDs) for photodynamic therapy (PDT) of malignant biliary obstruction.MethodsA prototype was constructed with red (640 nm) LEDs embedded in a 14.5 French polyurethane tube. The device was evaluated for optical power and subjected to physical and electrical tests. PDT-induced reactive oxygen species were imaged in a gel phantom.ResultsThe stent functioned at a 2.5-cm bend radius and illuminated for 6 months in saline. No stray currents were detected, and it was cool after 30 minutes of operation. Optical power of 5–15 mW is applicable to PDT. Imaging of a reactive oxygen indicator showed LED-stent activation of photosensitizer.ConclusionsThe results motivate biological testing and design optimization.
Fauna of Zoontic Parasites of Stray Dogs in Yasouj Suburbs in 2008

Directory of Open Access Journals (Sweden)

A Moshfe

2011-04-01

Full Text Available Introduction & Objective: Dogs are among the closest animals to human residents and can by useful for human. A few of zoontic diseases are prevalent in Iran. Dogs are the reservoirs of many of these zoonosis and a major role in transmission of infection. The aim of this study was to determine the zoonotic parasitic fauna of stray dogs in Yasuj Materials & Methods: In this descriptive study which was conducted at Yasuj suburbs in 2008, 25 dogs’ corpses were necropsied and their tissues were studied for parasitic infections. Collected parasites were placed in special containers and stained for genus and species diagnosis based on their morphological features. The collected data were analyzed with the SPSS software, using descriptive analysis. Results: Of the 25 studied corpses, 23 dogs were infected with at least one parasite. Helminthic infections of dogs were consisted of: Taenia hydatigena, Mesocestoides sp., Echinococcus granulosus, Dipylidium caninum, Macracanthorhynchus hirudinaceus and Spirocerca lupi. Conclusion: Four of six detected helminthes in in dogs in this study are zoonotic parasites which are important in human diseases. Among them larval stage of Echinococcus granulosus which causes hydatid cyst disease in human is very important. Control programs should be implemented in this region to prevent these zoonotic diseases.
Lighting. Eclairage

Energy Technology Data Exchange (ETDEWEB)

1989-01-01

Increasing energy costs have led to a review of the high costs of lighting. The use of new energy-efficient lighting equipment, coupled with the use of the proper quantity and quality of lighting only where it is needed, creates a potential for cost reduction. A manual is provided to aid the process of adapting Canadian industrial, commercial, and institutional enterprises to these higher costs. An introductory review of lighting fundamentals is presented, providing a basic understanding of concepts such as illumination, light output measurements, power requirements, lighting quality, and energy audit methods. The currently available lighting equipment used to achieve cost savings is then reviewed, including energy saving lamps and ballasts, controls, and automatic energy control systems. A number of energy management opportunities are identified, such as modification of lighting usage patterns, calculation of the optimum number of lighting fixtures, replacement of existing lamps, and the application of task lighting. Examples are included to show the cost savings possible when applying some of the techniques suggested. 27 figs., 11 tabs.
Detecting stray microwaves and nonequilibrium quasiparticles in thin films by single-electron tunneling

Science.gov (United States)

Saira, Olli-Pentti; Maisi, Ville; Kemppinen, Antti; Möttönen, Mikko; Pekola, Jukka

2013-03-01

Superconducting thin films and tunnel junctions are the building blocks of many state-of-the-art technologies related to quantum information processing, microwave detection, and electronic amplification. These devices operate at millikelvin temperatures, and - in a naive picture - their fidelity metrics are expected to improve as the temperature is lowered. However, very often one finds in the experiment that the device performance levels off around 100-150 mK. In my presentation, I will address three common physical mechanisms that can cause such saturation: stray microwaves, nonequilibrium quasiparticles, and sub-gap quasiparticle states. The new experimental data I will present is based on a series of studies on quasiparticle transport in Coulomb-blockaded normal-insulator-superconductor tunnel junction devices. We have used a capacitively coupled SET electrometer to detect individual quasiparticle tunneling events in real time. We demonstrate the following record-low values for thin film aluminum: quasiparticle density nqp < 0 . 033 / μm3 , normalized density of sub-gap quasiparticle states (Dynes parameter) γ < 1 . 6 ×10-7 . I will also discuss some sample stage and chip designs that improve microwave shielding.
Assessment of a Targeted Trap-Neuter-Return Pilot Study in Auckland, New Zealand.

Science.gov (United States)

Zito, Sarah; Aguilar, Glenn; Vigeant, Shalsee; Dale, Arnja

2018-05-13

There is a need for effective and humane management tools to manage urban stray cats and minimise negative impacts associated with stray cats. One such tool is targeted trap-neuter-return (TTNR), but no concerted implementation of this technique or formal assessments have been reported. To address this deficit, a TTNR programme was implemented and assessed in one Auckland suburb from May 2015 to June 2016; the programme sterilised and returned 348 cats (4.2 cats/1000 residents). Assessment was based on the number of incoming felines; stray, unsocialised cats euthanased; unsocialised, unowned cats sterilised and returned (independently of the TTNR programme); and neonatal/underage euthanasias. Incoming stray felines, underage euthanasias, and unsocialised stray cat euthanasias were all reduced for the targeted suburb when compared for the years before and after the programme (the percentage reduction in these parameters was −39, −17, −34, −7, and −47, respectively). These outcome measures had a greater reduction in the targeted suburb compared to the Auckland suburbs not targeted by the TTNR programme ( p < 0.01), although causation cannot be inferred, as a variety of reasons could have contributed to the changes. This pilot programme suggests that TTNR could be a valuable, humane cat management tool in urban New Zealand, and further assessment is warranted.
Office lighting systems: Optimization

Energy Technology Data Exchange (ETDEWEB)

Dagnino, U. (ENEL, Milan (Italy))

1990-09-01

Relative to office lighting systems, in particular, those making use of tubular fluorescent lamps, currently available on the international market, this paper tries to develop lighting system, design optimization criteria. The comparative assessment of the various design possibilities considers operating cost, energy consumption, and occupational comfort/safety aspects such as lighting level uniformity and equilibrium, reduction of glare and reflection, natural/artificial lighting balance, programmed switching, computerized control systems for multi-use requirements in large areas, programmed maintenance for greater efficiency and reliability.
Photophysics of BODIPY Dyes as Readily-Designable Photosensitisers in Light-Driven Proton Reduction

Directory of Open Access Journals (Sweden)

Laura Dura

2017-04-01

Full Text Available A series of boron dipyrromethene (BODIPY dyes was tested as photosensitisers for light-driven hydrogen evolution in combination with the complex [Pd(PPh3Cl2]2 as a source for catalytically-active Pd nanoparticles and triethylamine as a sacrificial electron donor. In line with earlier reports, halogenated dyes showed significantly higher hydrogen production activity. All BODIPYs were fully characterised using stationary absorption and emission spectroscopy. Time-resolved spectroscopic investigations on meso-mesityl substituted compounds revealed that reduction of the photo-excited BODIPY by the sacrificial agent occurs from an excited singlet state, while, in halogenated species, long-lived triplet states are present, determining electron transfer processes from the sacrificial agent. Quantum chemical calculations performed at the time-dependent density functional level of theory indicate that the differences in the photocatalytic performance of the present series of dyes can be correlated to the varying efficiency of intersystem crossing in non-halogenated and halogenated species and not to alterations in the energy levels introduced upon substitution.
Intercomparison of radiation protection devices in a high-energy stray neutron field. Part III: Instrument response

CERN Document Server

Silari, M; Beck, P; Bedogni, R; Cale, E; Caresana, M; Domingo, C; Donadille, L; Dubourg, N; Esposito, A; Fehrenbacher, G; Fernández, F; Ferrarini, M; Fiechtner, A; Fuchs, A; García, M J; Golnik, N; Gutermuth, F; Khurana, S; Klages, Th; Latocha, M; Mares, V; Mayer, S; Radon, T; Reithmeier, H; Rollet, S; Roos, H; Rühm, W; Sandri, S; Schardt, D; Simmer, G; Spurný, F; Trompier, F; Villa-Grasa, C; Weitzenegger, E; Wiegel, B; Wielunski, M; Wissmann, F; Zechner, A; Zielczyński, M

2009-01-01

The European Commission has funded within its 6th Framework Programme a three-year project (2005–2007) called CONRAD, COordinated Network for RAdiation Dosimetry. The organizational framework for this project was provided by the European radiation Dosimetry Group EURADOS. Work Package 6 of CONRAD dealt with “complex mixed radiation fields at workplaces” and in this context it organised a benchmark exercise, which included both measurements and calculations, in a stray radiation field at a high-energy particle accelerator at GSI, Germany. The aim was to intercompare the response of several types of active detectors and passive dosemeters in a well-characterised workplace field. The Monte Carlo simulations of the radiation field and the experimental determination of the neutron spectra with various Bonner Sphere Spectrometers are discussed in Rollet et al. (2008) and in Wiegel et al. (2008). This paper focuses on the intercomparison of the response of the dosemeters in terms of ambient dose equivalent. Th...
Energy Efficient Task Light

DEFF Research Database (Denmark)

Logadottir, Asta; Ardkapan, Siamak Rahimi; Johnsen, Kjeld

2014-01-01

The objectives of this work is to develop a task light for office lighting that fulfils the minimum requirements of the European standard EN12464 - 1 : Light and lighting – Lighting of work places, Part 1: Indoor workplaces and the Danish standard DS 700 : Lys og belysning I arbejdsrum , or more...... specifically the requirements that apply to the work area and the immediate surrounding area. By providing a task light that fulfils the requirements for task lighting and the immediate surrounding area, the general lighting only needs to provide the illuminance levels required for background lighting...... and thereby a reduction in installed power for general lighting of about 40 % compared to the way illuminance levels are designed in an office environment in Denmark today. This lighting strategy is useful when the placement of the task area is not defined in the space before the lighting is design ed...
Light Up the Word update 2001-2002 : solid state lighting for human development

Energy Technology Data Exchange (ETDEWEB)

Robertson, K.; Irvine-Halliday, D. [Calgary Univ., AB (Canada). Dept. of Electrical and Computer Engineering, Light Up the World Foundation; Craine, S. [Curtin Univ. of Technology (Australia)]|[Calgary Univ., AB (Canada). Dept. of Electrical and Computer Engineering, Light Up the World Foundation; Stone, R. [Fernbank Electronic Systems Ltd., Stittsville, ON (Canada)

2002-07-01

Light Up the World Foundation (LUTW) is a humanitarian organization founded in 1997 to bring safe, healthy, reliable, environmentally sound and affordable home lighting to developing countries. LUTW is a world leader in using solid state lighting (SSL) technologies to improve the quality of life for underprivileged people living in villages with little realistic prospect for affordable electrification. SSL technology uses white light-emitting diodes (LEDs) to provide lighting at low power consumption, often from batteries that get recharged by solar panels or other renewable energy sources. LUTW is active in more than 12 countries and has set the standards to raising the quality of SSL as a community development tool around the world. This report described how LUTW developed its market for SSL and the basic component for forging a relationship between industrial and social entrepreneurship. The international efforts to reduce greenhouse gas (GHG) emissions under climate change mitigation mechanisms such as carbon reduction emission credits, allows LUTW to obtain additional revenues to help sustain its projects. This is because the amount of fossil fuel and GHG reductions from SSL systems can be readily quantified. 4 refs., 1 tab., 1 fig.
Reduction of particle emissions from light duty vehicles and from taxies; Reduktion af partikelelemissioner fra varebiler og taxier

Energy Technology Data Exchange (ETDEWEB)

Nielsen, Johan; Henriques, M.; Weibel, T.G. [TetraPlan A/S (Denmark)

2006-11-03

This project, 'Reduction of particle emissions from light duty vehicles and from taxies', analyses different strategies to reduce the particle emission, their effect for particle emissions, and the resulting cost for the society and for the companies. The project describes the EU regulation of emissions, the possibilities of reducing the emissions via special requirements in environmental zones and the Danish taxation of light duty vehicles. Further, the project includes interviews with owners of light duty vehicles and taxies and also with Danish producers of particle filters. The strategies analysed in the scenarios include: 1) Promotion of particle filters; 2) Shift from diesel to gasoline and; 3) Downsizing. The effects for particle emissions and for mortality are described. Further, the costs and benefits for the society and the cost for the companies are evaluated. The effects of the scenarios are analysed, both for initiatives implemented at a national level and for implementation in an environmental zone in the municipality of Copenhagen. The main results are that the socioeconomic benefits in the year 2012 are greater than the costs, if taxis and light duty vehicles have filters installed and if they are driving in the Copenhagen area. For light duty vehicles it is only profitable, if the prices of the filters fall to the price level that is expected in the future in the study. Further, the analysis shows that for light duty vehicles and taxies driving all over the country, the socioeconomic benefits achieved by installing particle filters are too small to cover the costs. The analysis shows that it is also profitable socio-economically to change from diesel to petrol for light duty vehicles and for taxies (except taxies driving nationally). The analysis is based on the producer prices including the general net tax level, while the specific taxes are not included. From the point of view of the companies it is not profitable to change to petrol
Prevalence and characterization of Escherichia coli and Salmonella strains isolated from stray dog and coyote feces in a major leafy greens production region at the United States-Mexico border.

Directory of Open Access Journals (Sweden)

Michele T Jay-Russell

Full Text Available In 2010, Romaine lettuce grown in southern Arizona was implicated in a multi-state outbreak of Escherichia coli O145:H28 infections. This was the first known Shiga toxin-producing E. coli (STEC outbreak traced to the southwest desert leafy green vegetable production region along the United States-Mexico border. Limited information exists on sources of STEC and other enteric zoonotic pathogens in domestic and wild animals in this region. According to local vegetable growers, unleashed or stray domestic dogs and free-roaming coyotes are a significant problem due to intrusions into their crop fields. During the 2010-2011 leafy greens growing season, we conducted a prevalence survey of STEC and Salmonella presence in stray dog and coyote feces. Fresh fecal samples from impounded dogs and coyotes from lands near produce fields were collected and cultured using extended enrichment and serogroup-specific immunomagnetic separation (IMS followed by serotyping, pulsed-field gel electrophoresis (PFGE, and antimicrobial susceptibility testing. A total of 461 fecal samples were analyzed including 358 domestic dog and 103 coyote fecals. STEC was not detected, but atypical enteropathogenic E. coli (aEPEC strains comprising 14 different serotypes were isolated from 13 (3.6% dog and 5 (4.9% coyote samples. Salmonella was cultured from 33 (9.2% dog and 33 (32% coyote samples comprising 29 serovars with 58% from dogs belonging to Senftenberg or Typhimurium. PFGE analysis revealed 17 aEPEC and 27 Salmonella distinct pulsotypes. Four (22.2% of 18 aEPEC and 4 (6.1% of 66 Salmonella isolates were resistant to two or more antibiotic classes. Our findings suggest that stray dogs and coyotes in the desert southwest may not be significant sources of STEC, but are potential reservoirs of other pathogenic E. coli and Salmonella. These results underscore the importance of good agriculture practices relating to mitigation of microbial risks from animal fecal deposits in the
Measurement of stray radiation within a scanning proton therapy facility: EURADOS WG9 intercomparison exercise of active dosimetry systems

Energy Technology Data Exchange (ETDEWEB)

Farah, J., E-mail: jad.farah@irsn.fr; Trompier, F. [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Pôle Radioprotection de l’Homme, BP17, Fontenay-aux-Roses 92260 (France); Mares, V.; Schinner, K.; Wielunski, M. [Helmholtz Zentrum München, Institute of Radiation Protection, Ingolstädter Landstraße 1, Neuherberg 85764 (Germany); Romero-Expósito, M.; Domingo, C. [Departament de Física, Universitat Autònoma de Barcelona, Bellaterra E-08193 (Spain); Trinkl, S. [Helmholtz Zentrum München, Institute of Radiation Protection, Ingolstädter Landstraße 1, Neuherberg 85764, Germany and Physik-Department, Technische Universität München, Garching 85748 (Germany); Dufek, V. [Czech Technical University in Prague, FNSPE, Břehová 7, Prague 115 19, Czech Republic and National Radiation Protection Institute, Bartoškova 28, Prague 140 00 (Czech Republic); Klodowska, M.; Liszka, M.; Stolarczyk, L.; Olko, P. [Institute of Nuclear Physics PAN, Radzikowskiego 152, Krakow 31-342 (Poland); Kubancak, J. [Czech Technical University in Prague, FNSPE, Břehová 7, Prague 115 19, Czech Republic and Department of Radiation Dosimetry, Nuclear Physics Institute, Řež CZ-250 68 (Czech Republic); and others

2015-05-15

Purpose: To characterize stray radiation around the target volume in scanning proton therapy and study the performance of active neutron monitors. Methods: Working Group 9 of the European Radiation Dosimetry Group (EURADOS WG9—Radiation protection in medicine) carried out a large measurement campaign at the Trento Centro di Protonterapia (Trento, Italy) in order to determine the neutron spectra near the patient using two extended-range Bonner sphere spectrometry (BSS) systems. In addition, the work focused on acknowledging the performance of different commercial active dosimetry systems when measuring neutron ambient dose equivalents, H{sup ∗}(10), at several positions inside (8 positions) and outside (3 positions) the treatment room. Detectors included three TEPCs—tissue equivalent proportional counters (Hawk type from Far West Technology, Inc.) and six rem-counters (WENDI-II, LB 6411, RadEye™ NL, a regular and an extended-range NM2B). Meanwhile, the photon component of stray radiation was deduced from the low-lineal energy transfer part of TEPC spectra or measured using a Thermo Scientific™ FH-40G survey meter. Experiments involved a water tank phantom (60 × 30 × 30 cm{sup 3}) representing the patient that was uniformly irradiated using a 3 mm spot diameter proton pencil beam with 10 cm modulation width, 19.95 cm distal beam range, and 10 × 10 cm{sup 2} field size. Results: Neutron spectrometry around the target volume showed two main components at the thermal and fast energy ranges. The study also revealed the large dependence of the energy distribution of neutrons, and consequently of out-of-field doses, on the primary beam direction (directional emission of intranuclear cascade neutrons) and energy (spectral composition of secondary neutrons). In addition, neutron mapping within the facility was conducted and showed the highest H{sup ∗}(10) value of ∼51 μSv Gy{sup −1}; this was measured at 1.15 m along the beam axis. H{sup ∗}(10) values
Indoor Lighting Facilities

Science.gov (United States)

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

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

Directory of Open Access Journals (Sweden)

Tutsch Rainer

2015-01-01

Full Text Available Automated optical inspection is an important test procedure in electronic circuits assembly. Frequently 3d information is required and laser light sectioning sensors are often applied. However, some effects complicate the reliable automatic detection of the shape of such assemblies and their components. The packages of electronic components often are made of black plastics or ceramics so that the intensity available for the optical detection is quite low, especially in comparison to the surface of the PCBs where the components are mounted on. In addition due to rough surfaces of the components and the coherence length of the laser light speckle structures arise. In the work presented here a piezo actuator is used to oscillate the illuminating laser lines along the direction of the lines. The aim is to reduce the visibility of the speckle structures by averaging while maintaining the geometrical shape of the lines. In addition, image processing methods like segmentation and skeletonization are used to allow the detection of the shape of components and assemblies also if materials with distinct differences in the reflectivity are involved. Investigations include the influence of the parameters amplitude and frequency of the piezo actuator.
The estimated effect of mass or footprint reduction in recent light-duty vehicles on U.S. societal fatality risk per vehicle mile traveled.

Science.gov (United States)

Wenzel, Tom

2013-10-01

The National Highway Traffic Safety Administration (NHTSA) recently updated its 2003 and 2010 logistic regression analyses of the effect of a reduction in light-duty vehicle mass on US societal fatality risk per vehicle mile traveled (VMT; Kahane, 2012). Societal fatality risk includes the risk to both the occupants of the case vehicle as well as any crash partner or pedestrians. The current analysis is the most thorough investigation of this issue to date. This paper replicates the Kahane analysis and extends it by testing the sensitivity of his results to changes in the definition of risk, and the data and control variables used in the regression models. An assessment by Lawrence Berkeley National Laboratory (LBNL) indicates that the estimated effect of mass reduction on risk is smaller than in Kahane's previous studies, and is statistically non-significant for all but the lightest cars (Wenzel, 2012a). The estimated effects of a reduction in mass or footprint (i.e. wheelbase times track width) are small relative to other vehicle, driver, and crash variables used in the regression models. The recent historical correlation between mass and footprint is not so large to prohibit including both variables in the same regression model; excluding footprint from the model, i.e. allowing footprint to decrease with mass, increases the estimated detrimental effect of mass reduction on risk in cars and crossover utility vehicles (CUVs)/minivans, but has virtually no effect on light trucks. Analysis by footprint deciles indicates that risk does not consistently increase with reduced mass for vehicles of similar footprint. Finally, the estimated effects of mass and footprint reduction are sensitive to the measure of exposure used (fatalities per induced exposure crash, rather than per VMT), as well as other changes in the data or control variables used. It appears that the safety penalty from lower mass can be mitigated with careful vehicle design, and that manufacturers can

Prevalence of selected infectious disease agents in stray cats in Catalonia, Spain

Directory of Open Access Journals (Sweden)

Sara Ravicini

2016-02-01

Full Text Available Objectives The objective of the current study was to investigate the prevalence rates of the following infectious agents in 116 stray cats in the Barcelona area of Spain: Anaplasma phagocytophilum, Bartonella species, Borrelia burgdorferi, Chlamydia felis, Dirofilaria immitis, Ehrlichia species, feline calicivirus (FCV, feline herpesvirus-1 (FHV-1, feline leukaemia virus (FeLV, feline immunodeficiency virus (FIV, haemoplasmas, Mycoplasma species and Rickettsia species. Methods Serum antibodies were used to estimate the prevalence of exposure to A phagocytophilum, Bartonella species, B burgdorferi, Ehrlichia species and FIV; serum antigens were used to assess for infection by D immitis and FeLV; and molecular assays were used to amplify nucleic acids of Anaplasma species, Bartonella species, C felis, D immitis, Ehrlichia species, FCV, FHV-1, haemoplasmas, Mycoplasma species and Rickettsia species from blood and nasal or oral swabs. Results Of the 116 cats, 63 (54.3% had evidence of infection by Bartonella species, FeLV, FIV or a haemoplasma. Anaplasma species, Ehrlichia species or Rickettsia species DNA was not amplified from these cats. A total of 18/116 cats (15.5% were positive for FCV RNA (six cats, Mycoplasma species DNA (six cats, FHV-1 DNA (three cats or C felis DNA (three cats. Conclusions and relevance This study documents that shelter cats in Catalonia are exposed to many infectious agents with clinical and zoonotic significance, and that flea control is indicated for cats in the region.
Visualization of gas dissolution following upward gas migration in porous media: Technique and implications for stray gas

Science.gov (United States)

Van De Ven, C. J. C.; Mumford, Kevin G.

2018-05-01

The study of gas-water mass transfer in porous media is important in many applications, including unconventional resource extraction, carbon storage, deep geological waste storage, and remediation of contaminated groundwater, all of which rely on an understanding of the fate and transport of free and dissolved gas. The novel visual technique developed in this study provided both quantitative and qualitative observations of gas-water mass transfer. Findings included interaction between free gas architecture and dissolved plume migration, plume geometry and longevity. The technique was applied to the injection of CO2 in source patterns expected for stray gas originating from oil and gas operations to measure dissolved phase concentrations of CO2 at high spatial and temporal resolutions. The data set is the first of its kind to provide high resolution quantification of gas-water dissolution, and will facilitate an improved understanding of the fundamental processes of gas movement and fate in these complex systems.
Synergistic photocatalysis of Cr(VI) reduction and 4-Chlorophenol degradation over hydroxylated α-Fe{sub 2}O{sub 3} under visible light irradiation

Energy Technology Data Exchange (ETDEWEB)

Wang, Ji-Chao; Ren, Juan [College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450002 (China); Yao, Hong-Chang, E-mail: yaohongchang@zzu.edu.cn [College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450002 (China); Zhang, Lin; Wang, Jian-She; Zang, Shuang-Quan [College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450002 (China); Han, Li-Feng [Henan Provincial Key Laboratory of Surface & Interface Science, Zhengzhou University of Light Industry, Zhengzhou 450002 (China); Li, Zhong-Jun, E-mail: lizhongjun@zzu.edu.cn [College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450002 (China)

2016-07-05

Highlights: • The surface hydroxyl of Fe{sub 2}O{sub 3} influences on the Cr(VI) reduction activity. • The synergistic photocatalysis enhances degradation activity of Cr(VI) and 4-CP. • The Fe{sub 2}O{sub 3} catalyst exhibits good stability and degradation activity after 9 runs. - Abstract: A series of Fe{sub 2}O{sub 3} materials with hydroxyl are synthesized in different monohydric alcohol (C{sub 2} – C{sub 5}) solvents by solvothermal method and characterized by XRD, BET, XPS, TG and EA. The amount of hydroxyl is demonstrated to be emerged on the surface of the as-synthesized Fe{sub 2}O{sub 3} particles and their contents are determined to be from 7.99 to 3.74 wt%. The Cr(VI) reduction experiments show that the hydroxyl content of Fe{sub 2}O{sub 3} samples exacts great influence on the photocatalytic activity under visible light irradiation (λ > 400 nm) and that the Fe{sub 2}O{sub 3} sample synthesized in n-butyl alcohol exhibits the optimal photocatalytic activity. The synergistic photocatalysis for 4-Chlorophenol (4-CP) degradation and Cr(VI) reduction over above Fe{sub 2}O{sub 3} sample is further investigated. The photocatalytic ratio of Cr(VI) reduction are enhanced from 24.8% to 70.2% while that of 4-CP oxidation are increased from 13.5% to 47.8% after 1 h visible light irradiation. The Fe{sub 2}O{sub 3} sample keeps good degradation rates of mixed pollutants after 9 runs. The active oxygen intermediates O{sub 2}{sup −}·, ·OH and H{sub 2}O{sub 2} formed in the photoreaction process are discovered by ESR measurement and UV–vis test. The photocatalytic degradation mechanism is proposed accordingly.
Estimation of snow albedo reduction by light absorbing impurities using Monte Carlo radiative transfer model

Science.gov (United States)

Sengupta, D.; Gao, L.; Wilcox, E. M.; Beres, N. D.; Moosmüller, H.; Khlystov, A.

2017-12-01

Radiative forcing and climate change greatly depends on earth's surface albedo and its temporal and spatial variation. The surface albedo varies greatly depending on the surface characteristics ranging from 5-10% for calm ocean waters to 80% for some snow-covered areas. Clean and fresh snow surfaces have the highest albedo and are most sensitive to contamination with light absorbing impurities that can greatly reduce surface albedo and change overall radiative forcing estimates. Accurate estimation of snow albedo as well as understanding of feedbacks on climate from changes in snow-covered areas is important for radiative forcing, snow energy balance, predicting seasonal snowmelt, and run off rates. Such information is essential to inform timely decision making of stakeholders and policy makers. Light absorbing particles deposited onto the snow surface can greatly alter snow albedo and have been identified as a major contributor to regional climate forcing if seasonal snow cover is involved. However, uncertainty associated with quantification of albedo reduction by these light absorbing particles is high. Here, we use Mie theory (under the assumption of spherical snow grains) to reconstruct the single scattering parameters of snow (i.e., single scattering albedo ῶ and asymmetry parameter g) from observation-based size distribution information and retrieved refractive index values. The single scattering parameters of impurities are extracted with the same approach from datasets obtained during laboratory combustion of biomass samples. Instead of using plane-parallel approximation methods to account for multiple scattering, we have used the simple "Monte Carlo ray/photon tracing approach" to calculate the snow albedo. This simple approach considers multiple scattering to be the "collection" of single scattering events. Using this approach, we vary the effective snow grain size and impurity concentrations to explore the evolution of snow albedo over a wide
Solid-state lighting-a benevolent technology

International Nuclear Information System (INIS)

Schubert, E Fred; Kim, Jong Kyu; Luo Hong; Xi, J-Q

2006-01-01

Solid-state light sources are in the process of profoundly changing the way humans generate light for general lighting applications. Solid-state light sources possess two highly desirable features, which set them apart from most other light sources: (i) they have the potential to create light with essentially unit power efficiency and (ii) the properties of light, such as spectral composition and temporal modulation, can be controlled to a degree that is not possible with conventional light sources such as incandescent and fluorescent lamps. The implications are enormous and, as a consequence, many positive developments are to be expected including a reduction in global energy consumption, reduction of global-warming-gas and pollutant emissions and a multitude of new functionalities benefiting numerous applications. This review will assess the impact of solid-state lighting technology on energy consumption, the environment and on emerging application fields that make use of the controllability afforded by solid-state sources. The review will also discuss technical areas that fuel continued progress in solid-state lighting. Specifically, we will review the use of novel phosphor distributions in white light-emitting diodes (LEDs) and show the strong influence of phosphor distribution on efficiency. We will also review the use of reflectors in LEDs with emphasis on 'perfect' reflectors, i.e. reflectors with highly reflective omni-directional characteristics. Finally, we will discuss a new class of thin-film materials with an unprecedented low refractive index. Such low-n materials may strongly contribute to the continuous progress in solid-state lighting
K-correlation power spectral density and surface scatter model

Science.gov (United States)

Dittman, Michael G.

2006-08-01

The K-Correlation or ABC model for surface power spectral density (PSD) and BRDF has been around for years. Eugene Church and John Stover, in particular, have published descriptions of its use in describing smooth surfaces. The model has, however, remained underused in the optical analysis community partially due to the lack of a clear summary tailored toward that application. This paper provides the K-Correlation PSD normalized to σ(λ) and BRDF normalized to TIS(σ,λ) in a format intended to be used by stray light analysts. It is hoped that this paper will promote use of the model by analysts and its incorporation as a standard tool into stray light modeling software.
Global auroral imaging instrumentation for the dynamics explorer mission

International Nuclear Information System (INIS)

Frank, L.A.; Craven, J.D.; Ackerson, K.L.; English, M.R.; Eather, R.H.; Carovillano, R.L.

1981-01-01

The instrumentation for gaining global images of the auroral oval from the high-altitude spacecraft of the Dynamics Explorer Mission is described. Three spin-scan auroral imaging (SAI) photometers are expected to be able to effectively view the dim emissions from earth in the presence of strong stray light sources near their fields-of-view along the sunlit portion of the spacecraft orbit. A special optical design which includes an off-axis parabolic mirror as the focusing element and super-reflecting mirror surfaces is used to minimize the effects of stray light. The rotation of the spacecraft and an instrument scanning mirror provide the two-dimensional array of pixels comprising an image frame. (orig.)
Morning reduction of photosynthetic capacity before midday depression.

Science.gov (United States)

Koyama, Kohei; Takemoto, Shuhei

2014-03-17

Midday depression of photosynthesis has important consequences for ecosystem carbon exchange. Recent studies of forest trees have demonstrated that latent reduction of photosynthetic capacity can begin in the early morning, preceding the midday depression. We investigated whether such early morning reduction also occurs in an herbaceous species, Oenothera biennis. Diurnal changes of the photosynthetic light response curve (measured using a light-emitting diode) and incident sunlight intensity were measured under field conditions. The following results were obtained: (1) the light-saturated photosynthetic rate decreased beginning at sunrise; (2) the incident sunlight intensity on the leaves increased from sunrise; and (3) combining (1) and (2), the net photosynthetic rate under natural sunlight intensity increased from sunrise, reached a maximum at mid-morning, and then showed midday depression. Our results demonstrate that the latent morning reduction of photosynthetic capacity begins at sunrise, preceding the apparent midday depression, in agreement with previous studies of forest trees.
Equipment of Thomson scattering measurement on DIVA plasma

International Nuclear Information System (INIS)

Yamauchi, Toshihiko; Kumagai, Katsuaki; Funahashi, Akimasa; Matoba, Thoru; Sengoku, Seio

1980-02-01

Equipment of Thomson scattering measurement using ruby-laser light is explained. DIVA device was shut down in September 1979; it gave numerous fruitful experimental results during its five years operation. We measured the profiles of electron temperature and density with the Thomson scattering equipment, which played an important role in research of the energy confinement and heating characteristics. In Thomson scattering measurements on DIVA, studies and improvements were made for reduction of stray light, increase of measuring points and data processing. The profile of electron temperature and density were thus measured successful. In this report is given an over-all view of the Thomson scattering equipment together with the above improvements. As two representative examples, the measured results of electron temperature profiles on DIVA plasma under divertor operation and low-q discharge respectively are described. (author)
Separation and Recovery of Uranium Metal from Spent Light Water Reactor Fuel via Electrolytic Reduction and Electrorefining

International Nuclear Information System (INIS)

Herrmann, S.D.; Li, S.X.

2010-01-01

A series of bench-scale experiments was performed in a hot cell at Idaho National Laboratory to demonstrate the separation and recovery of uranium metal from spent light water reactor (LWR) oxide fuel. The experiments involved crushing spent LWR fuel to particulate and separating it from its cladding. Oxide fuel particulate was then converted to metal in a series of six electrolytic reduction runs that were performed in succession with a single salt loading of molten LiCl - 1 wt% Li2O at 650 C. Analysis of salt samples following the series of electrolytic reduction runs identified the diffusion of select fission products from the spent fuel to the molten salt electrolyte. The extents of metal oxide conversion in the post-test fuel were also quantified, including a nominal 99.7% conversion of uranium oxide to metal. Uranium metal was then separated from the reduced LWR fuel in a series of six electrorefining runs that were performed in succession with a single salt loading of molten LiCl-KCl-UCl3 at 500 C. Analysis of salt samples following the series of electrorefining runs identified additional partitioning of fission products into the molten salt electrolyte. Analyses of the separated uranium metal were performed, and its decontamination factors were determined.
Metallic coating deposited by Cold Gas Spray onto Light alhoys

OpenAIRE

Villa Vidaller, Maria

2013-01-01

This thesis focuses on the use of Cold Gas Spray technology (CGS) to spray different nature powders onto light alloys with the aim of increasing their wear resistance. The growing industrial interest for costs reduction (fuel consumption, machinery lifetime, or personal security) has emphasized the necessity to investigate the potential applications that light alloys can offer. Weight reduction is a reason why light metals and its alloys have been associated with strong industries a...
The efficiency challenge of nitride light-emitting diodes for lighting

KAUST Repository

Weisbuch, Claude

2015-03-13

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. We discuss the challenges of light-emitting diodes in view of their application to solid-state lighting. The requirement is to at least displace the quite efficient fluorescent, sodium, and high intensity discharge lamps used today in the main energy consuming lighting sectors, industrial, commercial and outdoors, with more efficient and better light quality lamps. We show that both from the point of view of cost of ownership and carbon emissions reduction, the relevant metric is efficiency, more than the cost of lumens. Then, progress from present performance requires identification of the loss mechanisms in light emission from LEDs, and solutions competing with mainstream c-plane LEDS grown on sapphire need to be on par with these. Special attention is devoted to a discussion of the efficiency droop mechanisms, and of a recent direct measurement of Auger generated electrons which appear to be responsible for droop.
Preparation of perovskite type titanium-bearing blast furnace slag photocatalyst doped with sulphate and investigation on reduction Cr(VI) using UV-vis light

International Nuclear Information System (INIS)

Lei, X.F.; Xue, X.X.

2008-01-01

Perovskite type titanium-bearing blast furnace slag (TBBFS) and sulphate-modified titanium-bearing blast furnace slag (SO 4 2- /TBBFS) photocatalysts were prepared by the high-energy ball milling method at different calcination temperature. The photocatalysts were characterized by XRD, FTIR, UV-vis diffuse reflectance spectra and SEM measurements. The photocatalytic activities of the different catalysts were evaluated by the photocatalytic reduction of Cr(VI) under UV-vis light irradiation. For the photocatalytic reduction of Cr(VI), the photocatalytic activities of TBBFS catalysts were found to be strongly dependent of the calcination temperature and TBBFS calcined at 700 deg. C showed a higher photocatalytic activity compared to other TBBFS catalysts. In contrast, sulphation of TBBFS improved the photocatalytic activities of SO 4 2- /TBBFS catalysts. At low calcination temperature, the photocatalytic activities of SO 4 2- /TBBFS catalysts were markedly higher than TBBFS prepared under high calcination temperature, suggesting that the presence of surface SO 4 2- favored the photocatalytic reduction of Cr(VI)
Improvements to the MST Thomson Scattering Diagnostic

Science.gov (United States)

Adams, D. T.; Borchardt, M. T.; den Hartog, D. J.; Holly, D. J.; Kile, T.; Kubala, S. Z.; Jacobson, C. M.; Thomas, M. A.; Wallace, J. P.; Young, W. C.; MST Thomson Scattering Team

2017-10-01

Multiple upgrades to the MST Thomson Scattering diagnostic have been implemented to expand capabilities of the system. In the past, stray laser light prevented electron density measurements everywhere and temperature measurements for -z/a >0.75. To mitigate stray light, a new laser beamline is being commissioned that includes a longer entrance flight tube, close-fitting apertures, and baffles. A polarizer has been added to the collection optics to further reduce stray light. An absolute density calibration using Rayleigh scattering in argon will be performed. An insertable integrating sphere will provide a full-system spectral calibration as well as maps optical fibers to machine coordinates. Reduced transmission of the collection optics due to coatings from plasma-surface interactions is regularly monitored to inform timely replacements of the first lens. Long-wavelength filters have been installed to better characterize non-Maxwellian electron distribution features. Previous work has identified residual photons not described by a Maxwellian distribution during m =0 magnetic bursts. Further effort to characterize the distribution function will be described. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Fusion Energy Sciences program under Award No. DE-FC02-05ER54814.
The European Commission's light bulb decree: Another costly regulation?

International Nuclear Information System (INIS)

Frondel, Manuel; Lohmann, Steffen

2011-01-01

Since September 2009, Regulation 244/2009 of the European Commission enforces the gradual phase-out of incandescent light bulbs. As of September 2012, only energy-efficient lighting sources will be allowed for sale. Among these are halogen light bulbs, light-emitting diodes (LED), or compact fluorescent light bulbs-often referred to as energy-saving light bulbs. The Commission's justification for the phase-out of conventional light bulbs maintains that a reduction in the electricity consumed will not only lead to lower energy cost for private households and industrial consumers, but at the same time lead to a decrease in greenhouse gas emissions. This article discusses possible reasons for the slow market diffusion of energy-saving light bulbs and shows that the investment in energy-efficient light bulbs does not necessarily lead to significant cost reductions. Drawing on some illustrative examples, we demonstrate that the use of cheaper incandescent bulbs instead of energy-saving light bulbs can be economically rational in cases of rather low usage times, in which the higher initial purchasing price might only pay off after very long time spans. Furthermore, due to the coexistence with the European Emissions Trading Scheme (ETS), this regulation attains no additional emission reductions beyond those achieved by the ETS alone. We thus conclude that the general ban of incandescent light bulbs is inappropriate and should be abolished by the Commission. - Research highlights: → This article discusses reasons for the slow market diffusion of energy-saving light bulbs. → We show that using incandescent bulbs can be rational in cases of rather low usage times. → We conclude that the general ban of incandescent light bulbs should be abolished by the Commission.
A cocatalyst-free Eosin Y-sensitized p-type of Co₃O₄ quantum dot for highly efficient and stable visible-light-driven water reduction and hydrogen production.

Science.gov (United States)

Zhang, Ning; Shi, Jinwen; Niu, Fujun; Wang, Jian; Guo, Liejin

2015-09-07

Owing to the effect of energy band bending, p-type Co3O4 quantum dots sensitized by Eosin Y showed a high and stable photocatalytic activity (∼13,440 μmol h(-1) g(-1)(cat)) for water reduction and hydrogen production under visible-light irradiation without any cocatalyst.
Nerium oleander indirect leaf photosynthesis and light harvesting reductions after clipping injury or Spodoptera eridania herbivory: high sensitivity to injury.

Science.gov (United States)

Delaney, Kevin J

2012-04-01

Variable indirect photosynthetic rate (P(n)) responses occur on injured leaves after insect herbivory. It is important to understand factors that influence indirect P(n) reductions after injury. The current study examines the relationship between gas exchange and chlorophyll a fluorescence parameters with injury intensity (% single leaf tissue removal) from clipping or Spodoptera eridania Stoll (Noctuidae) herbivory on Nerium oleander L. (Apocynaceae). Two experiments showed intercellular [CO(2)] increases but P(n) and stomatal conductance reductions with increasing injury intensity, suggesting non-stomatal P(n) limitation. Also, P(n) recovery was incomplete at 3d post-injury. This is the first report of a negative exponential P(n) impairment function with leaf injury intensity to suggest high N. oleander leaf sensitivity to indirect P(n) impairment. Negative linear functions occurred between most other gas exchange and chlorophyll a fluorescence parameters with injury intensity. The degree of light harvesting impairment increased with injury intensity via lower (1) photochemical efficiency indicated lower energy transfer efficiency from reaction centers to PSII, (2) photochemical quenching indicated reaction center closure, and (3) electron transport rates indicated less energy traveling through PSII. Future studies can examine additional mechanisms (mesophyll conductance, carbon fixation, and cardenolide induction) to cause N. oleander indirect leaf P(n) reductions after injury. Published by Elsevier Ireland Ltd.
Rotational Raman scattering using molecular nitrogen gas for calibration of Thomson-scattering apparatus

International Nuclear Information System (INIS)

Yamauchi, Toshihiko; Nakazawa, Ichiro

1987-01-01

Anti-Stokes rotational Raman lines in molecular nitrogen gas were used for the calibration of Thomson-scattering apparatus. It was found that molecular nitrogen gas is suitable for a vessel having strong stray light. The polarization ratio was 0.16 using linear-polarized laser light. (author)
Photocatalytic Reduction of Hexavalent Chromium Induced by Photolysis of Ferric/tartrate Complex

Energy Technology Data Exchange (ETDEWEB)

Feng, Xianghua; Ding, Shimin; Zhang, Lixian [Yangtze Normal Univ., Fuling (China)

2012-11-15

Photocatalytic reduction of hexavalent chromium (Cr(VI)) in ferric-tartrate system under irradiation of visible light was investigated. Effects of light resources, initial pH value and initial concentration of various reactants on Cr(VI) photocatalytic reduction were studied. Photoreaction kinetics was discussed and a possible photochemical pathway was proposed. The results indicate that Fe(III)-tartrate system is able to rapidly and effectively photocatalytically reduce Cr(VI) utilizing visible light. Initial pH variations results in the concentration changes of Fe(III)-tartrate complex in this system, and pH at 3.0 is optimal for Cr(VI) photocatalytic reduction. Efficiency of Cr(VI) photocatalytic reduction increases with increasing initial concentrations of Cr(VI), Fe(III) and tartrate. Kinetics analysis indicates that initial Fe(III) concentration affects Cr(VI) photoreduction most significantly.
Photocatalytic Reduction of Hexavalent Chromium Induced by Photolysis of Ferric/tartrate Complex

International Nuclear Information System (INIS)

Feng, Xianghua; Ding, Shimin; Zhang, Lixian

2012-01-01

Photocatalytic reduction of hexavalent chromium (Cr(VI)) in ferric-tartrate system under irradiation of visible light was investigated. Effects of light resources, initial pH value and initial concentration of various reactants on Cr(VI) photocatalytic reduction were studied. Photoreaction kinetics was discussed and a possible photochemical pathway was proposed. The results indicate that Fe(III)-tartrate system is able to rapidly and effectively photocatalytically reduce Cr(VI) utilizing visible light. Initial pH variations results in the concentration changes of Fe(III)-tartrate complex in this system, and pH at 3.0 is optimal for Cr(VI) photocatalytic reduction. Efficiency of Cr(VI) photocatalytic reduction increases with increasing initial concentrations of Cr(VI), Fe(III) and tartrate. Kinetics analysis indicates that initial Fe(III) concentration affects Cr(VI) photoreduction most significantly

Colloidal silver nanoparticles prepared by UV-light induced citrate reduction technique for the quantitative detection of uric acid

Science.gov (United States)

Maity, Anupam; Panda, Sovan Kumar

2018-04-01

Reddish-yellow color colloid consisting of silver nanoparticles (Ag NPs) has been synthesized by reducing aqueous AgNO3 solution by photo-induced citrate reduction technique under UV light. As prepared colloid exhibits single and intense plasmonic absorption peak in the violet region of the visible spectra with the peak centered at 405 nm. The NPs are fine and spherical with diameter ranging from 5 to 10 nm. These colloidal NPs have been used for the quantitative detection of uric acid by UV-VIS spectroscopy. A linear red shifting of the characteristics Plasmonic absorption peak of Ag NPs is observed with uric acid concentration. Uric acid can be detected by UV-VIS spectroscopy down to 5 nM limit using the prepared colloid.
Pathogen reduction of blood components.

Science.gov (United States)

Solheim, Bjarte G

2008-08-01

Thanks to many blood safety interventions introduced in developed countries the risk of transfusion transmitted infections has become exceedingly small in these countries. However, emerging pathogens still represent a serious challenge, as demonstrated by West Nile virus in the US and more recently by Chikungunya virus in the Indian Ocean. In addition bacterial contamination, particularly in platelets, and protozoa transmitted by blood components still represent sizeable risks in developed countries. In developing countries the risk of all transfusion transmitted infections is still high due to insufficient funding and organisation of the health service. Pathogen reduction of pooled plasma products has virtually eliminated the risk of transfusion transmitted infections, without compromising the quality of the products significantly. Pathogen reduction of blood components has been much more challenging. Solvent detergent treatment which has been so successfully applied for plasma products dissolves cell membranes, and can, therefore, only be applied for plasma and not for cellular blood components. Targeting of nucleic acids has been another method for pathogen inactivation of plasma and the only approach possible for cellular blood products. As documented in more than 15 year's track record, solvent detergent treatment of pooled plasma can yield high quality plasma. The increased risk for contamination by unknown viruses due to pooling is out weighed by elimination of TRALI, significant reduction in allergic reactions and standardisation of the product. Recently, a promising method for solvent detergent treatment of single donor plasma units has been published. Methylene blue light treatment of single donor plasma units has a similar long track record as pooled solvent detergent treated plasma; but the method is less well documented and affects coagulation factor activity more. Psoralen light treated plasma has only recently been introduced (CE marked in Europe
Sensitivity Analysis and Stray Capacitance of Helical Flux Compression Generator with Multi Layer Filamentary Conductor in Rectangular Cross-Section

Directory of Open Access Journals (Sweden)

M. E. Mosleh

2012-03-01

Full Text Available This paper presents an approach to calculate the equivalent stray capacitance (SC of n-turn of the helical flux compression generator (HFCG coil with multi layer conductor wire filaments (MLCWF in the form of rectangular cross-section. This approach is based on vespiary regular hexagonal (VRH model. In this method, wire filaments of the generator coil are separated into many very small similar elementary cells. By the expanded explosion in the liner and move explosion to the end of the liner, the coil turns number will be reduced. So, the equivalent SC of the HFCG will increase. The results show that by progress of explosion and decrease of the turns’ number in the generator coil total capacitance of the generator increases until the explosion reaches to the second turn. When only one turn remains in the circuit, a decrease occurs in the total capacitance of the generator.
A capital cost reduction study on the fast breeder reactor plant

International Nuclear Information System (INIS)

Taniyama, H.; Kamei, M.; Moriyama, M.

1991-01-01

A capital cost reduction study has been performed for large fast breeder reactor designs. The primary objective of this study is to show a trend of capital cost reduction between FBR plants at the prototype stage, the demonstration stage, and the future commercialization stage. For the FBR plant at the demonstration stage a construction cost comparison with a light water reactor has also been performed, and the target cost of FBR of below 1.5 times that of the light water reactor cost was achieved. To extend the capital cost reduction study, a feasibility study was made to achieve a capital cost of an FBR less than that of a light water reactor. The recommended design is shown as a future commercialization FBR design concept. (author)
Effect of 670-nm Light-Emitting Diode Light On Neuronal Cultures

Science.gov (United States)

Wong-Riley, Margaret T. T.; Whelan, Harry T.

2002-01-01

Light close to and within the near infrared range has documented benefits for promoting wound healing in human and animal studies. Our preliminary results using light-emitting diodes (LEDs) in this range have also demonstrated two-to five-fold increases in growth-phase-specific DNA synthesis in normal fibroblasts, muscle cells, osteoblasts, and mucosal epithelial cells in tissue cultures. However, the mechanisms of action of such light on cells are poorly understood. We hypothesized that the therapeutic effects of such light result from the stimulation of cellular events associated with increases in cytochrome oxidase activity. As a first step in testing our hypothesis, we subjected primary neuronal cultures to impulse blockade by tetrodotoxin (TTX), a voltage-dependent sodium channel blocker, and applied LED light at 670 nm to determine if it could partially or fully reverse the reduction of cytochrome oxidase activity by TTX. The wavelength and parameters were previously tested to be beneficial for wound healing.
Consensus and new improvements of disability glare

Directory of Open Access Journals (Sweden)

Yu-Wei Zheng

2014-12-01

Full Text Available Patients with early cataract may have normal visual acuity(VAbut complain that they have problems in driving at night, like seeing things through a veil. This phenomenon is defined as disability glare which maybe caused by growing stray light. Patients with intraocular lens following cataract surgery may complain about glare, halos and shadows in visual field, which are also resulted from dysphotopia. Disability glare is the VA loss due to disturbing luminance in visual field. In other words, it's the retinal contrast sensitivity reduction because of the straylight. This article contains the consensus and new progress of disability glare. It provides solutions according to its effect factors and offers clues for further study.
Non-Destructive Monitoring of Charge-Discharge Cycles on Lithium Ion Batteries using 7Li Stray-Field Imaging

Science.gov (United States)

Tang, Joel A.; Dugar, Sneha; Zhong, Guiming; Dalal, Naresh S.; Zheng, Jim P.; Yang, Yong; Fu, Riqiang

2013-01-01

Magnetic resonance imaging provides a noninvasive method for in situ monitoring of electrochemical processes involved in charge/discharge cycling of batteries. Determining how the electrochemical processes become irreversible, ultimately resulting in degraded battery performance, will aid in developing new battery materials and designing better batteries. Here we introduce the use of an alternative in situ diagnostic tool to monitor the electrochemical processes. Utilizing a very large field-gradient in the fringe field of a magnet, stray-field-imaging (STRAFI) technique significantly improves the image resolution. These STRAFI images enable the real time monitoring of the electrodes at a micron level. It is demonstrated by two prototype half-cells, graphite∥Li and LiFePO4∥Li, that the high-resolution 7Li STRAFI profiles allow one to visualize in situ Li-ions transfer between the electrodes during charge/discharge cyclings as well as the formation and changes of irreversible microstructures of the Li components, and particularly reveal a non-uniform Li-ion distribution in the graphite. PMID:24005580
Comparison of the performance of different instruments in the stray neutron field around the CERN Proton Synchrotron.

Science.gov (United States)

Aza, Eleni; Caresana, Marco; Cassell, Christopher; Colombo, Valeria; Damjanovic, Sanja; Gilardoni, Simone; Manessi, Giacomo Paolo; Pangallo, Michel; Perrin, Daniel; Silari, Marco

2014-10-01

This paper discusses an intercomparison campaign carried out in several locations around the CERN Proton Synchrotron. The locations were selected in order to perform the measurements in different stray field conditions. Various neutron detectors were employed: ionisation chambers, conventional and extended range rem counters, both commercial and prototype ones, including a novel instrument called LUPIN, specifically conceived to work in pulsed fields. The attention was focused on the potential differences in the instrument readings due to dead-time losses that are expected to affect most commercial units. The results show that the ionisation chambers and LUPIN agree well with the expected H*(10) values, as derived from FLUKA simulations, showing no relevant underestimations even in strongly pulsed fields. On the contrary, the dead-time losses of the other rem counters induced an underestimation in pulsed fields that was more important for instruments characterised by a higher dead time. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
METIS: the visible and UV coronagraph for solar orbiter

Science.gov (United States)

Romoli, M.; Landini, F.; Antonucci, E.; Andretta, V.; Berlicki, A.; Fineschi, S.; Moses, J. D.; Naletto, G.; Nicolosi, P.; Nicolini, G.; Spadaro, D.; Teriaca, L.; Baccani, C.; Focardi, M.; Pancrazzi, M.; Pucci, S.; Abbo, L.; Bemporad, A.; Capobianco, G.; Massone, G.; Telloni, D.; Magli, E.; Da Deppo, V.; Frassetto, F.; Pelizzo, M. G.; Poletto, L.; Uslenghi, M.; Vives, S.; Malvezzi, M.

2017-11-01

METIS coronagraph is designed to observe the solar corona with an annular field of view from 1.5 to 2.9 degrees in the visible broadband (580-640 nm) and in the UV HI Lyman-alpha, during the Sun close approaching and high latitude tilting orbit of Solar Orbiter. The big challenge for a coronagraph is the stray light rejection. In this paper after a description of the present METIS optical design, the stray light rejection design is presented in detail together with METIS off-pointing strategies throughout the mission. Data shown in this paper derive from the optimization of the optical design performed with Zemax ray tracing and from laboratory breadboards of the occultation system and of the polarimeter.
Intercomparison of radiation protection devices in a high-energy stray neutron field. Part III: Instrument response

International Nuclear Information System (INIS)

Silari, M.; Agosteo, S.; Beck, P.; Bedogni, R.; Cale, E.; Caresana, M.; Domingo, C.; Donadille, L.; Dubourg, N.; Esposito, A.; Fehrenbacher, G.; Fernandez, F.; Ferrarini, M.; Fiechtner, A.; Fuchs, A.; Garcia, M.J.; Golnik, N.; Gutermuth, F.; Khurana, S.; Klages, Th.

2009-01-01

The European Commission has funded within its 6th Framework Programme a three-year project (2005-2007) called CONRAD, COordinated Network for RAdiation Dosimetry. The organizational framework for this project was provided by the European radiation Dosimetry Group EURADOS. Work Package 6 of CONRAD dealt with 'complex mixed radiation fields at workplaces' and in this context it organised a benchmark exercise, which included both measurements and calculations, in a stray radiation field at a high-energy particle accelerator at GSI, Germany. The aim was to intercompare the response of several types of active detectors and passive dosemeters in a well-characterised workplace field. The Monte Carlo simulations of the radiation field and the experimental determination of the neutron spectra with various Bonner Sphere Spectrometers are discussed in Rollet et al. (2008) and in Wiegel et al. (2008). This paper focuses on the intercomparison of the response of the dosemeters in terms of ambient dose equivalent. The paper describes in detail the detectors employed in the experiment, followed by a discussion of the results. A comparison is also made with the H*(10) values predicted by the Monte Carlo simulations and those measured by the BSS systems.
Calculated Hanle transmission and absorption spectra of the 87Rb D1 line with residual magnetic field for arbitrarily polarized light

International Nuclear Information System (INIS)

Noh, Heung-Ryoul; Moon, Han Seb

2010-01-01

This paper reports a theoretical study on the transmission spectra of an arbitrarily polarized laser beam through a rubidium cell with or without a buffer gas in Hanle-type coherent population trapping (CPT). This study examined how laser polarization, transverse magnetic field, and collisions with buffer gas affects the spectrum. The transmission spectrum due to CPT and the absorption spectrum due to the level crossing absorption (LCA) were calculated according to the laser polarization. The results show that the LCA is strongly dependent on the transverse magnetic field and interaction time of the atoms with a laser light via collisions with the buffer gas. In addition, the spectral shape of the calculated Hanle spectrum is closely related to the direction between the (stray) transverse magnetic field and polarization of the laser.
Preparation of Cu2O modified TiO2 nanopowder and its application to the visible light photoelectrocatalytic reduction of CO2 to CH3OH

Science.gov (United States)

Li, Bin; Niu, Wenchao; Cheng, Yongwei; Gu, Junjie; Ning, Ping; Guan, Qingqing

2018-05-01

Cu2O/TiO2 nanopowders were prepared and used as thin film electrode raw materials for CO2 photoelectroreduction. Characterization results from XRD, TEM, UV-Vis and BET show that Cu2O/TiO2 composites have regular morphology, narrow band gap, excellent textural properties, and exhibits marked response of visible light. The photoelectrocatalytic results show that CO2 can be reduced to formaldehyde (i.e., intermediate) and finally methanol (i.e., end product). In addition, the CO2 photoelectroreduction pathway and the mechanism of photoelectrocatalysis are discussed. In summary, the work reports a potential method of CO2 reduction by visible-light photocatalysis without an external bias.
Highly efficient visible light photocatalytic reduction of CO2 to hydrocarbon fuels by Cu-nanoparticle decorated graphene oxide.

Science.gov (United States)

Shown, Indrajit; Hsu, Hsin-Cheng; Chang, Yu-Chung; Lin, Chang-Hui; Roy, Pradip Kumar; Ganguly, Abhijit; Wang, Chen-Hao; Chang, Jan-Kai; Wu, Chih-I; Chen, Li-Chyong; Chen, Kuei-Hsien

2014-11-12

The production of renewable solar fuel through CO2 photoreduction, namely artificial photosynthesis, has gained tremendous attention in recent times due to the limited availability of fossil-fuel resources and global climate change caused by rising anthropogenic CO2 in the atmosphere. In this study, graphene oxide (GO) decorated with copper nanoparticles (Cu-NPs), hereafter referred to as Cu/GO, has been used to enhance photocatalytic CO2 reduction under visible-light. A rapid one-pot microwave process was used to prepare the Cu/GO hybrids with various Cu contents. The attributes of metallic copper nanoparticles (∼4-5 nm in size) in the GO hybrid are shown to significantly enhance the photocatalytic activity of GO, primarily through the suppression of electron-hole pair recombination, further reduction of GO's bandgap, and modification of its work function. X-ray photoemission spectroscopy studies indicate a charge transfer from GO to Cu. A strong interaction is observed between the metal content of the Cu/GO hybrids and the rates of formation and selectivity of the products. A factor of greater than 60 times enhancement in CO2 to fuel catalytic efficiency has been demonstrated using Cu/GO-2 (10 wt % Cu) compared with that using pristine GO.
Effects of shielding coatings on the anode shaping process during counter-rotating electrochemical machining

Science.gov (United States)

Wang, Dengyong; Zhu, Zengwei; Wang, Ningfeng; Zhu, Di

2016-09-01

Electrochemical machining (ECM) has been widely used in the aerospace, automotive, defense and medical industries for its many advantages over traditional machining methods. However, the machining accuracy in ECM is to a great extent limited by the stray corrosion of the unwanted material removal. Many attempts have been made to improve the ECM accuracy, such as the use of a pulse power, passivating electrolytes and auxiliary electrodes. However, they are sometimes insufficient for the reduction of the stray removal and have their limitations in many cases. To solve the stray corrosion problem in CRECM, insulating and conductive coatings are respectively used. The different implement processes of the two kinds of coatings are introduced. The effects of the two kinds of shielding coatings on the anode shaping process are investigated. Numerical simulations and experiments are conducted for the comparison of the two coatings. The simulation and experimental results show that both the two kinds of coatings are valid for the reduction of stray corrosion on the top surface of the convex structure. However, for insulating coating, the convex sidewall becomes concave when the height of the convex structure is over 1.26 mm. In addition, it is easy to peel off by the high-speed electrolyte. In contrast, the conductive coating has a strong adhesion, and can be well reserved during the whole machining process. The convex structure fabricated by using a conductive iron coating layer presents a favorable sidewall profile. It is concluded that the conductive coating is more effective for the improvement of the machining quality in CRECM. The proposed shielding coatings can also be employed to reduce the stray corrosion in other schemes of ECM.
Reduction of Bacterial Pathogens and Potential Surrogates on the Surface of Almonds Using High-Intensity 405-Nanometer Light.

Science.gov (United States)

Lacombe, Alison; Niemira, Brendan A; Sites, Joseph; Boyd, Glenn; Gurtler, Joshua B; Tyrell, Breanna; Fleck, Melissa

2016-11-01

The disinfecting properties of high-intensity monochromatic blue light (MBL) were investigated against Escherichia coli O157:H7, Salmonella , and nonpathogenic bacteria inoculated onto the surface of almonds. MBL was generated from an array of narrow-band 405-nm light-emitting diodes. Almonds were inoculated with higher or lower levels (8 or 5 CFU/g) of pathogenic E. coli O157:H7 and Salmonella , as well as nonpathogenic E. coli K-12 and an avirulent strain of Salmonella Typhimurium, for evaluation as potential surrogates for their respective pathogens. Inoculated almonds were treated with MBL for 0, 1, 2, 4, 6, 8, and 10 min at a working distance of 7 cm. Simultaneous to treatment, cooling air was directed onto the almonds at a rate of 4 ft 3 /min (1.89 ×10 -3 m 3 /s), sourced through a container of dry ice. An infrared camera was used to monitor the temperature readings after each run. For E. coli K-12, reductions of up to 1.85 or 1.63 log CFU/g were seen for higher and lower inoculum levels, respectively; reductions up to 2.44 and 1.44 log CFU/g were seen for E. coli O157:H7 (higher and lower inoculation levels, respectively). Attenuated Salmonella was reduced by up to 0.54 and 0.97 log CFU/g, whereas pathogenic Salmonella was reduced by up to 0.70 and 0.55 log CFU/g (higher and lower inoculation levels, respectively). Inoculation level did not significantly impact minimum effective treatment times, which ranged from 1 to 4 min. Temperatures remained below ambient throughout treatment, indicating that MBL is a nonthermal antimicrobial process. The nonpathogenic strains of E. coli and Salmonella each responded to MBL in a comparable manner to their pathogenic counterparts. These results suggest that these nonpathogenic strains may be useful in experiments with MBL in which a surrogate is required, and that MBL warrants further investigation as a potential antimicrobial treatment for low-moisture foods.
Nanostructure Secondary-Mirror Apodizing Mask for Transmitter Signal Suppression in a Duplex Telescope

Science.gov (United States)

Hagopian, John; Livas, Jeffrey; Shiri, Shahram; Getty, Stephanie; Tveekrem, June; Butler, James

2012-01-01

A document discusses a nanostructure apodizing mask, made of multi-walled carbon nanotubes, that is applied to the centers (or in and around the holes) of the secondary mirrors of telescopes that are used to interferometrically measure the strain of space-time in response to gravitational waves. The shape of this ultra-black mask can be adjusted to provide a smooth transition to the clear aperture of the secondary mirror to minimize diffracted light. Carbon nanotubes grown on silicon are a viable telescope mirror substrate, and can absorb significantly more light than other black treatments. The hemispherical reflectance of multi-walled carbon nanotubes grown at GSFC is approximately 3 to 10 times better than a standard aerospace paint used for stray light control. At the LISA (Laser Interferometer Space Antenna) wavelength of 1 micron, the advantage over paint is a factor of 10. Primarily, in the center of the secondary mirror (in the region of central obscuration, where no received light is lost) a black mask is applied to absorb transmitted light that could be reflected back into the receiver. In the LISA telescope, this is in the center couple of millimeters. The shape of this absorber is critical to suppress diffraction at the edge. By using the correct shape, the stray light can be reduced by approximately 10 to the 9 orders of magnitude versus no center mask. The effect of the nanotubes has been simulated in a stray-light model. The effect of the apodizing mask has been simulated in a near-field diffraction model. Specifications are geometry-dependent, but the baseline design for the LISA telescope has been modeled as well. The coatings are somewhat fragile, but work is continuing to enhance adhesion.
Light-regulation of enzyme activity in anacystis nidulans (Richt.).

Science.gov (United States)

Duggan, J X; Anderson, L E

1975-01-01

The effect of light on the levels of activity of six enzymes which are light-modulated in higher plants was examined in the photosynthetic procaryot Anacystis nidulans. Ribulose-5-phosphate kinase (EC 2.7.1.19) was found to be light-activated in vivo and dithiothreitol-activated in vitro while glucose-6-phosphate dehydrogenase (EC 1.1.1.49) was light-inactivated and dithiothreitol-inactivated. The enzymes fructose-1,6-diphosphate phosphatase (EC 3.1.3.11), sedoheptulose-1,7-diphosphate phosphatase, NAD- and NADP-linked glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.12; EC 1.2.1.13) were not affected by light treatment of the intact algae, but sedoheptulose-diphosphate phosphatase and the glyceraldehyde-3-phosphate dehydrogenases were dithiothreitol-activated in crude extracts. Light apparently controls the activity of the reductive and oxidative pentose phosphate pathway in this photosynthetic procaryot as in higher plants, through a process which probably involves reductive modulation of enzyme activity.
PAPR Reduction in OFDM-based Visible Light Communication Systems Using a Combination of Novel Peak-value Feedback Algorithm and Genetic Algorithm

Science.gov (United States)

Deng, Honggui; Liu, Yan; Ren, Shuang; He, Hailang; Tang, Chengying

2017-10-01

We propose an enhanced partial transmit sequence technique based on novel peak-value feedback algorithm and genetic algorithm (GAPFA-PTS) to reduce peak-to-average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) signals in visible light communication (VLC) systems(VLC-OFDM). To demonstrate the advantages of our proposed algorithm, we analyze the flow of proposed technique and compare the performances with other techniques through MATLAB simulation. The results show that GAPFA-PTS technique achieves a significant improvement in PAPR reduction while maintaining low bit error rate (BER) and low complexity in VLC-OFDM systems.
Optical Design of the Camera for Transiting Exoplanet Survey Satellite (TESS)

Science.gov (United States)

Chrisp, Michael; Clark, Kristin; Primeau, Brian; Dalpiaz, Michael; Lennon, Joseph

2015-01-01

The optical design of the wide field of view refractive camera, 34 degrees diagonal field, for the TESS payload is described. This fast f/1.4 cryogenic camera, operating at -75 C, has no vignetting for maximum light gathering within the size and weight constraints. Four of these cameras capture full frames of star images for photometric searches of planet crossings. The optical design evolution, from the initial Petzval design, took advantage of Forbes aspheres to develop a hybrid design form. This maximized the correction from the two aspherics resulting in a reduction of average spot size by sixty percent in the final design. An external long wavelength pass filter was replaced by an internal filter coating on a lens to save weight, and has been fabricated to meet the specifications. The stray light requirements were met by an extended lens hood baffle design, giving the necessary off-axis attenuation.
New Carrollton Federal Building Lighting Retrofit Captures Cool Savings

Energy Technology Data Exchange (ETDEWEB)

None

2017-01-01

Case study describes how the U.S. General Services Administration cut a $291,000 annual lighting electric bill to an estimated $53,500 by upgrading their fluorescent lighting to a new LED troffer lighting and controls system in the New Carrollton Federal Building in Lanham, Maryland. The lighting project yielded an 82% reduction in energy use and earned GSA two awards for exemplary performance from the Interior Lighting Campaign in 2016.

Detection of stably bright squeezed light with the quantum noise reduction of 12.6 dB by mutually compensating the phase fluctuations.

Science.gov (United States)

Yang, Wenhai; Shi, Shaoping; Wang, Yajun; Ma, Weiguang; Zheng, Yaohui; Peng, Kunchi

2017-11-01

We present a mutual compensation scheme of three phase fluctuations, originating from the residual amplitude modulation (RAM) in the phase modulation process, in the bright squeezed light generation system. The influence of the RAM on each locking loop is harmonized by using one electro-optic modulator (EOM), and the direction of the phase fluctuation is manipulated by positioning the photodetector (PD) that extracts the error signal before or after the optical parametric amplifier (OPA). Therefore a bright squeezed light with non-classical noise reduction of π is obtained. By fitting the squeezing and antisqueezing measurement results, we confirm that the total phase fluctuation of the system is around 3.1 mrad. The fluctuation of the noise suppression is 0.2 dB for 3 h.
Precollimator Manufacturing for X-ray Telescopes, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Space-based x-ray telescopes currently involve the use of a precollimator (PC) to shield the optics from stray light. Each PC consists of cylindrical aluminum ribs...
Throwing new light on the reduction of CO2.

Science.gov (United States)

Ozin, Geoffrey A

2015-03-18

While the chemical energy in fossil fuels has enabled the rapid rise of modern civilization, their utilization and accompanying anthropogenic CO2 emissions is occurring at a rate that is outpacing nature's carbon cycle. Its effect is now considered to be irreversible and this could lead to the demise of human society. This is a complex issue without a single solution, yet from the burgeoning global research activity and development in the field of CO2 capture and utilization, there is light at the end of the tunnel. In this article a couple of recent advances are illuminated. Attention is focused on the discovery of gas-phase, light-assisted heterogeneous catalytic materials and processes for CO2 photoreduction that operate at sufficiently high rates and conversion efficiencies, and under mild conditions, to open a new pathway for an energy transition from today's "fossil fuel economy" to a new and sustainable "CO2 economy". Whichever of the competing CO2 capture and utilization approaches proves to be the best way forward for the development of a future CO2-based solar fuels economy, hopefully this can occur in a period short enough to circumvent the predicted adverse consequences of greenhouse gas climate change. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Large-area OLED lightings and their applications

International Nuclear Information System (INIS)

Park, J W; Shin, D C; Park, S H

2011-01-01

In this paper, we review the key issues related to the fabrication of large-area organic light-emitting devices (OLEDs) for lighting applications. We discuss the origin of a short-circuit problem, luminance non-uniformity, hot spot, efficiency reduction (power loss), and heat generation and present the way of suppressing them. We also introduce three different application areas of large-area OLED lighting panels. They can be integrated with a solar cell for power recycling or inorganic LEDs for emotional lightings. The feasibility of using OLEDs for the application of visible-light communications is also reviewed
Sound transit climate risk reduction project.

Science.gov (United States)

2013-09-01

The Climate Risk Reduction Project assessed how climate change may affect Sound Transit commuter rail, light rail, and express bus : services. The project identified potential climate change impacts on agency operations, assets, and long-term plannin...
Detection of small number of Giardia in biological materials prepared from stray dogs.

Science.gov (United States)

Esmailikia, Leila; Ebrahimzade, Elahe; Shayan, Parviz; Amininia, Narges

2017-12-20

Giardia lamblia is an intestinal protozoa with intermittent and low shedding especially in dogs, and the detection of Giardia is accompanied with problems such as sampling and diagnostic method. The objective of this study was to detection of Giardia in biological materials with low number of parasite using parasitological and molecular methods, and also to determine whether the examined stray dogs harbor known zoonotic genotype of Giardia. For this aim 85 fecal and duodenal samples were studied from which 1 was positive by Trichrome staining of stool, 4 were positive by staining of duodenal samples. The nested PCR analysis with primers derived from 18 SrRNA showed that the specific PCR product could be amplified in 4 stool and 4 duodenal samples. All positive samples in staining analysis were also positive in nested PCR. No amplification could be observed by nested PCR with primers derived from β giardin gene due to the single copy of gene. Interestingly, the extracted DNA from old fixed stained Giardia positive smears could be also amplified with primers derived from 18SrRNA gene. The sequence analysis of nested PCR products showed that they belong to the genotype D. In conclusion, it is to denote that the Trichrome or Giemsa methods were not suitable for the detection of small number of this parasite in stool and the nested PCR with primers derived from 18S rRNA gene can replace the traditional methods successfully. For detection of Giardia in stool, primers derived from β giardin will not be recommended.
Facile synthesis of AgI/BiOI-Bi{sub 2}O{sub 3} multi-heterojunctions with high visible light activity for Cr(VI) reduction

Energy Technology Data Exchange (ETDEWEB)

Wang, Qi [School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310018 (China); The Brook Byer Institute for Sustainable Systems and School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta 30332 (United States); Shi, Xiaodong; Liu, Enqin [School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310018 (China); Crittenden, John C. [The Brook Byer Institute for Sustainable Systems and School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta 30332 (United States); Ma, Xiangjuan; Zhang, Yi [School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310018 (China); Cong, Yanqing, E-mail: yqcong@hotmail.com [School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310018 (China)

2016-11-05

Graphical abstract: Highly visible-light-active AgI/BiOI-Bi{sub 2}O{sub 3} with multi-heterojunctions was developed. - Highlights: • Visible-light-active AgI/BiOI-Bi{sub 2}O{sub 3} with multi-heterojunctions was prepared. • Highly enhanced photocatalytic reduction of Cr(VI) was observed. • k{sub Cr(VI)} on AgI/BiOI-Bi{sub 2}O{sub 3} increased by ca.16 times relative to Bi{sub 2}O{sub 3}. • Decreased E{sub g}, shifted E{sub fb} and reduced charge transfer resistance were observed. • Simultaneous reduction of Cr(VI) and degradation of organics were achieved. - Abstract: AgI sensitized BiOI-Bi{sub 2}O{sub 3} composite (AgI/BiOI-Bi{sub 2}O{sub 3}) with multi-heterojunctions was prepared using simple etching-deposition process. Different characterization techniques were performed to investigate the structural, optical and electrical properties of the as-prepared photocatalysts. It was found that the ternary AgI/BiOI-Bi{sub 2}O{sub 3} composite exhibited: (1) improved photocurrent response, (2) smaller band gap, (3) greatly reduced charge transfer resistance and (4) negative shift of flat band potential, which finally led to easier generation and more efficient separation of photo-generated electron-hole pairs at the hetero-interfaces. Thus, for the reduction of Cr(VI), AgI/BiOI-Bi{sub 2}O{sub 3} exhibited excellent photocatalytic activity under visible light irradiation at near neutral pH. AgI/BiOI-Bi{sub 2}O{sub 3} was optimized when the initial molar ratio of KI to Bi{sub 2}O{sub 3} and AgNO{sub 3} to Bi{sub 2}O{sub 3} was 1:1 and 10%, respectively. The estimated k{sub Cr(VI)} on optimized AgI/BiOI-Bi{sub 2}O{sub 3} was about 16 times that on pure Bi{sub 2}O{sub 3}. Good stability was also observed in cyclic runs, indicating that the current multi-heterostructured photocatalyst is highly desirable for the remediation of Cr(VI)-containing wastewater.
Light-induced cation exchange for copper sulfide based CO2 reduction.

Science.gov (United States)

Manzi, Aurora; Simon, Thomas; Sonnleitner, Clemens; Döblinger, Markus; Wyrwich, Regina; Stern, Omar; Stolarczyk, Jacek K; Feldmann, Jochen

2015-11-11

Copper(I)-based catalysts, such as Cu2S, are considered to be very promising materials for photocatalytic CO2 reduction. A common synthesis route for Cu2S via cation exchange from CdS nanocrystals requires Cu(I) precursors, organic solvents, and neutral atmosphere, but these conditions are not compatible with in situ applications in photocatalysis. Here we propose a novel cation exchange reaction that takes advantage of the reducing potential of photoexcited electrons in the conduction band of CdS and proceeds with Cu(II) precursors in an aqueous environment and under aerobic conditions. We show that the synthesized Cu2S photocatalyst can be efficiently used for the reduction of CO2 to carbon monoxide and methane, achieving formation rates of 3.02 and 0.13 μmol h(-1) g(-1), respectively, and suppressing competing water reduction. The process opens new pathways for the preparation of new efficient photocatalysts from readily available nanostructured templates.
The European Commission's light bulb decree: Another costly regulation?

Energy Technology Data Exchange (ETDEWEB)

Frondel, Manuel, E-mail: frondel@rwi-essen.de [Ruhr-University Bochum (RUB), Ruhr-Graduate School in Economics (RGS Econ) (Germany); Rheinisch-Westfaelisches Institut fuer Wirtschaftsforschung (RWI), Hohenzollernstr. 1-3, 45128 Essen (Germany); Lohmann, Steffen [Rheinisch-Westfaelisches Institut fuer Wirtschaftsforschung (RWI), Hohenzollernstr. 1-3, 45128 Essen (Germany); Tinbergen Institute (Netherlands)

2011-06-15

Since September 2009, Regulation 244/2009 of the European Commission enforces the gradual phase-out of incandescent light bulbs. As of September 2012, only energy-efficient lighting sources will be allowed for sale. Among these are halogen light bulbs, light-emitting diodes (LED), or compact fluorescent light bulbs-often referred to as energy-saving light bulbs. The Commission's justification for the phase-out of conventional light bulbs maintains that a reduction in the electricity consumed will not only lead to lower energy cost for private households and industrial consumers, but at the same time lead to a decrease in greenhouse gas emissions. This article discusses possible reasons for the slow market diffusion of energy-saving light bulbs and shows that the investment in energy-efficient light bulbs does not necessarily lead to significant cost reductions. Drawing on some illustrative examples, we demonstrate that the use of cheaper incandescent bulbs instead of energy-saving light bulbs can be economically rational in cases of rather low usage times, in which the higher initial purchasing price might only pay off after very long time spans. Furthermore, due to the coexistence with the European Emissions Trading Scheme (ETS), this regulation attains no additional emission reductions beyond those achieved by the ETS alone. We thus conclude that the general ban of incandescent light bulbs is inappropriate and should be abolished by the Commission. - Research Highlights: > This article discusses reasons for the slow market diffusion of energy-saving light bulbs. > We show that using incandescent bulbs can be rational in cases of rather low usage times. > We conclude that the general ban of incandescent light bulbs should be abolished by the Commission.
Photocatalytic Reduction Activity of 001 TiO2 Codoped with F and Fe under Visible Light for Bromate Removal

Directory of Open Access Journals (Sweden)

Yan Zhang

2016-01-01

Full Text Available The presence of bromate in water is a well-known problem because of its toxic effects on human health, particularly its carcinogenic potential. Photocatalytic reduction is an attractive process for bromate removal. F- and Fe-codoped TiO2 (F-Fe-TiO2 with a {001} facet was successfully prepared, and its bromate-removal activity under visible light was examined. The microstructure, morphology, and chemical state of the doping elements and the optical property of the photocatalysts were examined using transmission electron microscopy (TEM, X-ray photoelectron spectroscopy (XPS, electron paramagnetic resonance (EPR, photoluminescence spectroscopy (PLS, and UV-Vis diffuse reflectance spectra (DRS. The results indicate that the optical properties of F-Fe-TiO2 with the {001} facet and cuboid morphology were obviously improved and its photocatalytic activity was significantly enhanced. The bromate solution of 100 μg/L was thoroughly removed with 0.5 g/L dosage of 1.0% F- and 0.08% Fe-codoped TiO2 composite within 1 hour under visible light.
Analysis of active and passive magnetic field reduction systems (MFRS) of the ITER NBI

International Nuclear Information System (INIS)

Roccella, M.; Lucca, F.; Roccella, R.; Pizzuto, A.; Ramogida, G.; Portone, A.; Tanga, A.; Formisano, A.; Martone, R.

2007-01-01

In ITER two heating (HNBI) and one diagnostic neutral beam injectors (DNBI) are foreseen. Inside these components there are very stringent limits on the magnetic field (the flux density must be below some G along the ion path and below 20 G in the neutralizing regions). To achieve these performances in an environment with high stray field due to the plasma and the poloidal field coils (PFC), both passive and active shielding systems have been foreseen. The present design of the magnetic field reduction systems (MFRS) is made of seven active coils and of a box surrounding the NBI region, consisting of ferromagnetic plates. The electromagnetic analyses of the effectiveness of these shields have been performed by a 3D FEM model using ANSYS code for the HNBI. The ANSYS models of the ferromagnetic box and of the active coils are fully parametric, thus any size change of the ferromagnetic box and coils (linear dimension or thickness) preserving the overall box shape could be easily reproduced by simply changing some parameter in the model
Analysis of active and passive magnetic field reduction systems (MFRS) of the ITER NBI

Energy Technology Data Exchange (ETDEWEB)

Roccella, M. [L.T. Calcoli S.a.S., Piazza Prinetti 26/B, Merate (Lecco) (Italy)], E-mail: roccella@ltcalcoli.it; Lucca, F.; Roccella, R. [L.T. Calcoli S.a.S., Piazza Prinetti 26/B, Merate (Lecco) (Italy); Pizzuto, A.; Ramogida, G. [Associazione EURATOM sulla Fusione - ENEA Frascati (Italy); Portone, A.; Tanga, A. [ITER EFDA (Italy); Formisano, A.; Martone, R. [CREATE Napoli (Italy)

2007-10-15

In ITER two heating (HNBI) and one diagnostic neutral beam injectors (DNBI) are foreseen. Inside these components there are very stringent limits on the magnetic field (the flux density must be below some G along the ion path and below 20 G in the neutralizing regions). To achieve these performances in an environment with high stray field due to the plasma and the poloidal field coils (PFC), both passive and active shielding systems have been foreseen. The present design of the magnetic field reduction systems (MFRS) is made of seven active coils and of a box surrounding the NBI region, consisting of ferromagnetic plates. The electromagnetic analyses of the effectiveness of these shields have been performed by a 3D FEM model using ANSYS code for the HNBI. The ANSYS models of the ferromagnetic box and of the active coils are fully parametric, thus any size change of the ferromagnetic box and coils (linear dimension or thickness) preserving the overall box shape could be easily reproduced by simply changing some parameter in the model.
Typical effects of laser dazzling CCD camera

Science.gov (United States)

Zhang, Zhen; Zhang, Jianmin; Shao, Bibo; Cheng, Deyan; Ye, Xisheng; Feng, Guobin

2015-05-01

In this article, an overview of laser dazzling effect to buried channel CCD camera is given. The CCDs are sorted into staring and scanning types. The former includes the frame transfer and interline transfer types. The latter includes linear and time delay integration types. All CCDs must perform four primary tasks in generating an image, which are called charge generation, charge collection, charge transfer and charge measurement. In camera, the lenses are needed to input the optical signal to the CCD sensors, in which the techniques for erasing stray light are used. And the electron circuits are needed to process the output signal of CCD, in which many electronic techniques are used. The dazzling effects are the conjunct result of light distribution distortion and charge distribution distortion, which respectively derive from the lens and the sensor. Strictly speaking, in lens, the light distribution is not distorted. In general, the lens are so well designed and fabricated that its stray light can be neglected. But the laser is of much enough intensity to make its stray light obvious. In CCD image sensors, laser can induce a so large electrons generation. Charges transfer inefficiency and charges blooming will cause the distortion of the charge distribution. Commonly, the largest signal outputted from CCD sensor is restricted by capability of the collection well of CCD, and can't go beyond the dynamic range for the subsequent electron circuits maintaining normal work. So the signal is not distorted in the post-processing circuits. But some techniques in the circuit can make some dazzling effects present different phenomenon in final image.
Evaluation of the participation of ferredoxin in oxygen reduction in the photosynthetic electron transport chain of isolated pea thylakoids.

Science.gov (United States)

Kozuleva, Marina A; Ivanov, Boris N

2010-07-01

The contribution to reduction of oxygen by ferredoxin (Fd) to the overall reduction of oxygen in isolated pea thylakoids was studied in the presence of Fd versus Fd + NADP(+). The overall rate of electron transport was measured using a determination of Photosystem II quantum yield from chlorophyll fluorescence parameters, and the rate of oxidation of Fd was measured from the light-induced redox changes of Fd. At low light intensity, increasing Fd concentration from 5 to 30 microM in the absence of NADP(+) increased the proportion of oxygen reduction by Fd from 25-35 to 40-60% in different experiments. This proportion decreased with increasing light intensity. When NADP(+) was added in the presence of 15 microM Fd, which was optimal for the NADP(+) reduction rate, the participation of Fd in the reduction of oxygen was low, no more than 10%, and it also decreased with increasing light intensity. At high light intensity, the overall oxygen reduction rates in the presence of Fd + NADP(+) and in the presence of Fd alone were comparable. The significance of reduction of dioxygen either by water-soluble Fd or by the membrane-bound carriers of the photosynthetic electron transport chain for redox signaling under different light intensities is discussed.
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.
Selection of full-sib families of Panicum maximum Jacq under low light conditions

Directory of Open Access Journals (Sweden)

Douglas Mochi Victor

2015-04-01

Full Text Available The silvopastoral system is a viable technological alternative to extensive cattle grazing, however, for it to be successful, forage grass genotypes adapted to reduced light need to be identified. The objective of this study was to select progenies of Panicum maximum tolerant to low light conditions for use in breeding programs and to study the genetic control and performance of some traits associated with shade tolerance. Six full-sib progenies were evaluated in full sun, 50% and 70% of light reduction in pots and subjected to cuttings. Progeny genotypic values (GV increased with light reduction in relation to plant height (H and specific leaf area (SLA. The traits total dry mass accumulation (DM and leaf dry mass accumulation (LDM had GV higher in 50% shade and intermediate in 70% shade. The GV of tiller number (TIL and root dry mass accumulation (RDM decreased with light reduction. The highest positive correlations were obtained for the traits H and RDM with SLA and DM; the highest negative correlations were between TIL and SLA and RDM, and H and LDM. The progenies showed higher tolerance to 50% light reduction and, among them, two stood out and will be used in breeding programs. It was also found that it is not necessary to evaluate some traits under all light conditions. All traits had high broad sense heritability and high genotypic correlation between progenies in all light intensities. There is genetic difference among the progenies regarding the response to different light intensities, which will allow selection for shade tolerance
Treatment of blood with a pathogen reduction technology using UV light and riboflavin inactivates Ebola virus in vitro

Science.gov (United States)

Cap, Andrew P.; Pidcoke, Heather F.; Keil, Shawn D.; Staples, Hilary M.; Anantpadma, Manu; Carrion, Ricardo; Davey, Robert A.; Frazer-Abel, Ashley; Taylor, Audra L.; Gonzales, Richard; Patterson, Jean L.; Goodrich, Raymond P.

2018-01-01

BACKGROUND Transfusion of plasma from recovered patients after Ebolavirus (EBOV) infection, typically called ‘convalescent plasma,’ is an effective treatment for active disease available in endemic areas, but carries the risk of introducing other pathogens, including other strains of EBOV. A pathogen reduction technology using ultraviolet light and riboflavin (UV + RB) is effective against multiple enveloped, negative-sense, single-stranded RNA viruses that are similar in structure to EBOV. We hypothesized that UV + RB is effective against EBOV in blood products without activating complement or reducing protective immunoglobulin titers that are important for the treatment of ebolavirus disease (EVD). STUDY DESIGN AND METHODS Four in vitro experiments were conducted to evaluate effects of UV + RB on green fluorescent protein EBOV (EBOV-GFP), wild-type EBOV in serum and whole blood, respectively, and on immunoglobulins and complement in plasma. Initial titers for Experiments 1–3 were: 4.21 log10 GFP units/mL, 4.96 log10 infectious units per mL, and 4.23 log10 plaque forming units per mL (PFU/mL). Conditions tested in the first three experiments included: 1. EBOV-GFP + UV + RB; 2. EBOV-GFP + RB only; 3 EBOV-GFP + UV only; 4. EBOV-GFP without RB or UV; 5. Virus-free control + UV only; and 6. Virus-free control without RB or UV. RESULTS UV + RB reduced EBOV titers to non-detectable levels in both non-human primate serum (≥ 2.8 to 3.2 log reduction) and human whole blood (≥ 3.0 log reduction) without decreasing protective antibody titers in human plasma. CONCLUSION Our in vitro results demonstrate that the UV + RB treatment efficiently reduces EBOV titers to below limits of detection in both serum and whole blood. In vivo testing to determine whether UV + RB can improve convalescent blood product safety is indicated. PMID:27001363
Treatment of blood with a pathogen reduction technology using ultraviolet light and riboflavin inactivates Ebola virus in vitro.

Science.gov (United States)

Cap, Andrew P; Pidcoke, Heather F; Keil, Shawn D; Staples, Hilary M; Anantpadma, Manu; Carrion, Ricardo; Davey, Robert A; Frazer-Abel, Ashley; Taylor, Audra L; Gonzales, Richard; Patterson, Jean L; Goodrich, Raymond P

2016-03-01

Transfusion of plasma from recovered patients after Ebolavirus (EBOV) infection, typically called "convalescent plasma," is an effective treatment for active disease available in endemic areas, but carries the risk of introducing other pathogens, including other strains of EBOV. A pathogen reduction technology using ultraviolet light and riboflavin (UV+RB) is effective against multiple enveloped, negative-sense, single-stranded RNA viruses that are similar in structure to EBOV. We hypothesized that UV+RB is effective against EBOV in blood products without activating complement or reducing protective immunoglobulin titers that are important for the treatment of Ebola virus disease (EVD). Four in vitro experiments were conducted to evaluate effects of UV+RB on green fluorescent protein EBOV (EBOV-GFP), wild-type EBOV in serum, and whole blood, respectively, and on immunoglobulins and complement in plasma. Initial titers for Experiments 1 to 3 were 4.21 log GFP units/mL, 4.96 log infectious units/mL, and 4.23 log plaque-forming units/mL. Conditions tested in the first three experiments included the following: 1-EBOV-GFP plus UV+RB; 2-EBOV-GFP plus RB only; 3-EBOV-GFP plus UV only; 4-EBOV-GFP without RB or UV; 5-virus-free control plus UV only; and 6-virus-free control without RB or UV. UV+RB reduced EBOV titers to nondetectable levels in both nonhuman primate serum (≥2.8- to 3.2-log reduction) and human whole blood (≥3.0-log reduction) without decreasing protective antibody titers in human plasma. Our in vitro results demonstrate that the UV+RB treatment efficiently reduces EBOV titers to below limits of detection in both serum and whole blood. In vivo testing to determine whether UV+RB can improve convalescent blood product safety is indicated. © 2016 AABB.
Modeling transitions in the California light-duty vehicles sector to achieve deep reductions in transportation greenhouse gas emissions

International Nuclear Information System (INIS)

Leighty, Wayne; Ogden, Joan M.; Yang, Christopher

2012-01-01

California’s target for reducing economy-wide greenhouse gas (GHG) emissions is 80% below 1990 levels by 2050. We develop transition scenarios for meeting this goal in California’s transportation sector, with focus on light-duty vehicles (LDVs). We explore four questions: (1) what options are available to reduce transportation sector GHG emissions 80% below 1990 levels by 2050; (2) how rapidly would transitions in LDV markets, fuels, and travel behaviors need to occur over the next 40 years; (3) how do intermediate policy goals relate to different transition pathways; (4) how would rates of technological change and market adoption between 2010 and 2050 impact cumulative GHG emissions? We develop four LDV transition scenarios to meet the 80in50 target through a combination of travel demand reduction, fuel economy improvements, and low-carbon fuel supply, subject to restrictions on trajectories of technological change, potential market adoption of new vehicles and fuels, and resource availability. These scenarios exhibit several common themes: electrification of LDVs, rapid improvements in vehicle efficiency, and future fuels with less than half the carbon intensity of current gasoline and diesel. Availability of low-carbon biofuels and the level of travel demand reduction are “swing factors” that influence the degree of LDV electrification required. - Highlights: ► We model change in California LDVs for deep reduction in transportation GHG emissions. ► Reduced travel demand, improved fuel economy, and low-carbon fuels are all needed. ► Transitions must begin soon and occur quickly in order to achieve the 80in50 goal. ► Low-C biofuel supply and travel demand influence the need for rapid LDV electrification. ► Cumulative GHG emissions from LDVs can differ between strategies by up to 40%.
Battery Charge Affects the Stability of Light Intensity from Light-emitting Diode Light-curing Units.

Science.gov (United States)

Tongtaksin, A; Leevailoj, C

discharged, with a coincident reduction in the units' ability to polymerize resin composite. Therefore, the intensity of an LED light-curing unit should be evaluated during the life of its battery charge to ensure that sufficient light intensity is being generated.

Visible light reduces C. elegans longevity.

Science.gov (United States)

De Magalhaes Filho, C Daniel; Henriquez, Brian; Seah, Nicole E; Evans, Ronald M; Lapierre, Louis R; Dillin, Andrew

2018-03-02

The transparent nematode Caenorhabditis elegans can sense UV and blue-violet light to alter behavior. Because high-dose UV and blue-violet light are not a common feature outside of the laboratory setting, we asked what role, if any, could low-intensity visible light play in C. elegans physiology and longevity. Here, we show that C. elegans lifespan is inversely correlated to the time worms were exposed to visible light. While circadian control, lite-1 and tax-2 do not contribute to the lifespan reduction, we demonstrate that visible light creates photooxidative stress along with a general unfolded-protein response that decreases the lifespan. Finally, we find that long-lived mutants are more resistant to light stress, as well as wild-type worms supplemented pharmacologically with antioxidants. This study reveals that transparent nematodes are sensitive to visible light radiation and highlights the need to standardize methods for controlling the unrecognized biased effect of light during lifespan studies in laboratory conditions.
Toxoplasma gondii, Dirofilaria immitis, feline immunodeficiency virus (FIV), and feline leukemia virus (FeLV) infections in stray and pet cats (Felis catus) in northwest China: co-infections and risk factors.

Science.gov (United States)

Cong, Wei; Meng, Qing-Feng; Blaga, Radu; Villena, Isabelle; Zhu, Xing-Quan; Qian, Ai-Dong

2016-01-01

This study was conducted to estimate the prevalence of Toxoplasma gondii, Dirofilaria immitis, feline immunodeficiency virus (FIV), and feline leukemia virus (FeLV) infections among stray and pet cats in Lanzhou, northwest China, and to identify the influence of age, gender, and regions on seropositivity. T. gondii antibodies were examined in cat sera by the modified agglutination test (MAT). The circulating antigens of D. immitis and FeLV and specific antibodies to FIV were examined using kits commercially available. The overall prevalence of T. gondii, FIV, FeLV, and D. immitis was 19.34, 9.12, 11.33, and 3.04 %, respectively. For the genetic characterization of T. gondii genotypes in cats, genomic DNA was extracted from the seropositive cats and the T. gondii B1 gene was amplified using a semi-nested PCR. DNA samples giving positive B1 amplification were then genotyped using multilocus PCR-RFLP. Two T. gondii genotypes (ToxoDB#9 and ToxoDB#1) were identified. Results of the multivariate logistic regression analysis showed that older cats are more likely to be seropositive than juveniles for T. gondii, FIV, FeLV, and D. immitis. This is the first report of T. gondii genotypes in cats in northwest China. Moreover, the present study is the first study of retrovirus and D. immitis seroprevalence in cats in China. The results revealed that T. gondii, FIV, and FeLV infections are common in stray and pet cats in northwest China.
Free-space laser communication technologies II; Proceedings of the Meeting, Los Angeles, CA, Jan. 15-17, 1990

Science.gov (United States)

Begley, David L. (Editor); Seery, Bernard D. (Editor)

1990-01-01

Various papers on free-space laser communication technologies are presented. Individual topics addressed include: optical intersatellite link experiment between the earth station and ETS-VI, the Goddard optical communications program, technologies and techniques for lasercom terminal size, weight, and cost reduction, laser beam acquisition and tracking system for ETS-VI laser communication equipment, analog dividers for acquisition and tracking signal normalization, fine pointing mechanism using multilayered piezoelectric actuator for optical ISL system, analysis of SILEX tracking sensor performance, new telescope concept for space communication, telescope considered as a very high gain antenna, design of compact transceiver optical systems for optical intersatellite links, ultralightweight optics for laser communications, highly sensitive measurement method for stray light and retroreflected light, depolarization effects on free space laser transceiver communication systems, in-orbit measurements of microaccelerations of ESA's communication satellite Olympus, high-performance laser diode transmitter for optical free space communication, diode-pumped Nd:host laser transmitter for intersatellite optical communications, single-frequency diode-pumped laser for free-space communication.
Diagnosis of canine echinococcosis: comparison of coproantigen detection with necropsy in stray dogs and red foxes from northern Jordan

Directory of Open Access Journals (Sweden)

El-Shehabi F.S.

2000-06-01

Full Text Available The sandwich enzyme linked immunosorbent assay (ELISA was used as a diagnostic test for Echinococcus granulosus infection by detecting coproantigens in 94 stray dogs Canis familiaris and eight red foxes (Vulpes vulpes from northern Jordan. The results were analyzed in relation to actual helminth infection as revealed by necropsy. The infection rate of dogs with E. granulosus was 13.8 % with a worm load ranging between 3 - > 10,000 per infected dog. In contrast, eight of 13 E. granulosus infected dogs were coproantigen positive (overall sensitivity 61.5 %. The sensitivity increased to 87.5 % and 100 % in dogs harboring > 20 and > 100 worms/dog, respectively. The specificity of coproantigen-ELISA was 91 %. The greatest cross-reactivity was found in dogs infected with Dipylidium caninum. The positive and negative predictive values for the coproantigen-ELISA test were 50 % and 94.2 %, respectively. Thus, a coproantigen negative dog is most probably truly negative for E. granulosus. In contrast, a coproantigen positive dog may not be truly positive for E. granulosus, except if it has a high worm burden of > 100 worms/animal.
Passive technologies for future large-scale photonic integrated circuits on silicon: polarization handling, light non-reciprocity and loss reduction

Directory of Open Access Journals (Sweden)

Daoxin Dai

2012-03-01

Full Text Available Silicon-based large-scale photonic integrated circuits are becoming important, due to the need for higher complexity and lower cost for optical transmitters, receivers and optical buffers. In this paper, passive technologies for large-scale photonic integrated circuits are described, including polarization handling, light non-reciprocity and loss reduction. The design rule for polarization beam splitters based on asymmetrical directional couplers is summarized and several novel designs for ultra-short polarization beam splitters are reviewed. A novel concept for realizing a polarization splitter–rotator is presented with a very simple fabrication process. Realization of silicon-based light non-reciprocity devices (e.g., optical isolator, which is very important for transmitters to avoid sensitivity to reflections, is also demonstrated with the help of magneto-optical material by the bonding technology. Low-loss waveguides are another important technology for large-scale photonic integrated circuits. Ultra-low loss optical waveguides are achieved by designing a Si3N4 core with a very high aspect ratio. The loss is reduced further to <0.1 dB m−1 with an improved fabrication process incorporating a high-quality thermal oxide upper cladding by means of wafer bonding. With the developed ultra-low loss Si3N4 optical waveguides, some devices are also demonstrated, including ultra-high-Q ring resonators, low-loss arrayed-waveguide grating (demultiplexers, and high-extinction-ratio polarizers.
Speckle reduction methods in laser-based picture projectors

Science.gov (United States)

Akram, M. Nadeem; Chen, Xuyuan

2016-02-01

Laser sources have been promised for many years to be better light sources as compared to traditional lamps or light-emitting diodes (LEDs) for projectors, which enable projectors having wide colour gamut for vivid image, super brightness and high contrast for the best picture quality, long lifetime for maintain free operation, mercury free, and low power consumption for green environment. A major technology obstacle in using lasers for projection has been the speckle noise caused by to the coherent nature of the lasers. For speckle reduction, current state of the art solutions apply moving parts with large physical space demand. Solutions beyond the state of the art need to be developed such as integrated optical components, hybrid MOEMS devices, and active phase modulators for compact speckle reduction. In this article, major methods reported in the literature for the speckle reduction in laser projectors are presented and explained. With the advancement in semiconductor lasers with largely reduced cost for the red, green and the blue primary colours, and the developed methods for their speckle reduction, it is hoped that the lasers will be widely utilized in different projector applications in the near future.
Development of Key Technologies for White Lighting Based on Light-Emitting Diodes (LEDs)

Energy Technology Data Exchange (ETDEWEB)

Werner Goetz; Bill Imler; James Kim; Junko Kobayashi; Andrew Kim; Mike Krames; Rick Mann; Gerd Mueller-Mach; Anneli Munkholm; Jonathan Wierer

2004-03-31

This program was organized to focus on materials development issues critical to the acceleration of solid-state lighting, and was split into three major thrust areas: (1) study of dislocation density reduction for GaN grown on sapphire using 'cantilever epitaxy', and the impact of dislocation density on the performance of state-of-the-art high-power LEDs; (2) the evaluation of in situ techniques for monitoring gas phase chemistry and the properties of GaN-based layers during metal-organic vapor phase epitaxy (MOCVD), and (3) feasibility for using semiconductor nanoparticles ('quantum dots') for the down-conversion of blue or ultraviolet light to generate white light. The program included a partnership between Lumileds Lighting (epitaxy and device fabrication for high power LEDs) and Sandia National Laboratories (cantilever epitaxy, gas phase chemistry, and quantum dot synthesis). Key findings included: (1) cantilever epitaxy can provide dislocation density reduction comparable to that of more complicated approaches, but all in one epitaxial growth step; however, further improvements are required to realize significant gains in LED performance at high drive currents, (2) in situ tools can provide detailed knowledge about gas phase chemistry, and can be used to monitor and control epitaxial layer composition and temperature to provide improved yields (e.g., a fivefold increase in color targeting is demonstrated for 540nm LEDs), and (3) quantum efficiency for quantum dots is improved and maintained up to 70% in epoxy thin films, but further work is necessary to increase densification (absorption) and robustness before practical application to LEDs.
Response of conifer species from three latitudinal populations to light spectra generated by light-emitting diodes and high-pressure sodium lamps

Science.gov (United States)

Kent G. Apostol; Kas Dumroese; Jeremy Pinto; Anthony S. Davis

2015-01-01

Light-emitting diode (LED) technology shows promise for supplementing photosynthetically active radiation (PAR) in forest nurseries because of the potential reduction in energy consumption and an ability to supply discrete wavelengths to optimize seedling growth. Our objective was to examine the effects of light spectra supplied by LED and traditional high-pressure...
FIR laser scattering and heterodyne receiver measurements on Alcator C

International Nuclear Information System (INIS)

Woskoboinikow, P.; Praddaude, H.C.; Mulligan, W.J.; Cohn, D.R.; Lax, B.

1982-01-01

The MIT program to develop high power collective Thomson scattering diagnostics is presented. The D 2 O laser Thomson scattering system is operational on Alcator C tokamak. The major components include a 0.5 MW, 150 ns D 2 O laser, a heterodyne receiver mixer, a 25 MW, 381 μ DCOOD laser local oscillator and X-band I.F. electronics including a 32 channel multiplexer filter centered at 9.4 GHz with 80 MHz wide channels. Initial scattering measurement showed high level of stray D 2 O laser power. The spectrum was obtained by operating the Thomson scattering diagnostics with no plasma in the tokamak. An X-band notch filter was placed after the Schottky diode mixer to reject a 240 MHz band centered at 9.4 GHz. The stray light level was reduced by 16 to 20 db. Other sources of background noise such as strong non-thermal scattering and ECE did not appear to be a problem. A gas filled cell was placed on the Alcator C scattering system to reduce the level of stray light. Work is underway to improve the transverse mode quality of the laser and receiver to improve matching to the beam and viewing dumps. (Kato, T.)
Improved availability through reduction in rework

International Nuclear Information System (INIS)

Grosswald, M.; Lowman, J.

1985-01-01

The Florida Power and Light Company Quality Improvement Rework Identification Program is discussed. Establishment of the Quality Improvement Rework Identification Task Team, goals, and methods of the program are noted. Resulting from the program are reductions in failure frequency and positive incentives from a teamwork approach
Emissions from light and medium goods vehicles in Denmark

DEFF Research Database (Denmark)

Jørgensen, Kaj

1996-01-01

The article analyses atmospheric pollution of light goods vehicles (i.e. freight vehicles lighter than 6 tonnes) and medium goods vehicles (i.e. 6-24 t delivery trucks) in Denmark, and evaluated the scope for emission reductions. Light goods vehicles are very inefficient vehicles, and moreover have...
Reductive and oxidative degradation of iopamidol, iodinated X-ray contrast media, by Fe(III)-oxalate under UV and visible light treatment.

Science.gov (United States)

Zhao, Cen; Arroyo-Mora, Luis E; DeCaprio, Anthony P; Sharma, Virender K; Dionysiou, Dionysios D; O'Shea, Kevin E

2014-12-15

Iopamidol, widely employed as iodinated X-ray contrast media (ICM), is readily degraded in a Fe(III)-oxalate photochemical system under UV (350 nm) and visible light (450 nm) irradiation. The degradation is nicely modeled by pseudo first order kinetics. The rates of hydroxyl radical (OH) production for Fe(III)-oxalate/H2O2/UV (350 nm) and Fe(III)-oxalate/H2O2/visible (450 nm) systems were 1.19 ± 0.12 and 0.30 ± 0.01 μM/min, respectively. The steady-state concentration of hydroxyl radical (OH) for the Fe(III)-oxalate/H2O2/UV (350 nm) conditions was 10.88 ± 1.13 × 10(-14) M and 2.7 ± 0.1 × 10(-14) M for the Fe(III)-oxalate/H2O2/visible (450 nm). The rate of superoxide anion radical (O2(-)) production under Fe(III)-oxalate/H2O2/UV (350 nm) was 0.19 ± 0.02 μM/min with a steady-state concentration of 5.43 ± 0.473 × 10(-10) M. Detailed product studies using liquid chromatography coupled to Q-TOF/MS demonstrate both reduction (multiple dehalogenations) and oxidation (aromatic ring and side chains) contribute to the degradation pathways. The reduction processes appear to be initiated by the carbon dioxide anion radical (CO2(-)) while oxidation processes are consistent with OH initiated reaction pathways. Unlike most advanced oxidation processes the Fe(III)-oxalate/H2O2/photochemical system can initiate to both reductive and oxidative degradation processes. The observed reductive dehalogenation is an attractive remediation strategy for halogenated organic compounds as the process can dramatically reduce the formation of the problematic disinfection by-products often associated with oxidative treatment processes. Copyright © 2014 Elsevier Ltd. All rights reserved.
Visible light CrO{sub 4}{sup 2-} reduction using the new CuAlO{sub 2}/CdS hetero-system

Energy Technology Data Exchange (ETDEWEB)

Brahimi, R. [Centre of Research in Physical and Chemical Analysis (CRAPC), BP 248, RP 16004 Algiers (Algeria); Laboratory of Storage and Valorization of Renewable Energies, Faculty of Chemistry (USTHB), BP 32 16111 Algiers (Algeria); Bessekhouad, Y. [Laboratory of Storage and Valorization of Renewable Energies, Faculty of Chemistry (USTHB), BP 32 16111 Algiers (Algeria); National Veterinary High School, BP 16111 Algiers (Algeria); Nasrallah, N. [Laboratory of Storage and Valorization of Renewable Energies, Faculty of Chemistry (USTHB), BP 32 16111 Algiers (Algeria); Trari, M., E-mail: solarchemistry@gmail.com [Laboratory of Storage and Valorization of Renewable Energies, Faculty of Chemistry (USTHB), BP 32 16111 Algiers (Algeria)

2012-06-15

Graphical abstract: Pseudo-first order kinetic for CrO{sub 4}{sup 2-} photoreduction for various concentrations. Highlights: Black-Right-Pointing-Pointer The work deals with the chromium reduction over CuAlO{sub 2}/CdS hetero-system. Black-Right-Pointing-Pointer The conduction band of CdS (-1.08 V) is more negative than the CrO{sub 4}{sup 2-}/Cr{sup 3+} level. Black-Right-Pointing-Pointer The sensitizer CuAlO{sub 2} has been synthesized by sol-gel. Black-Right-Pointing-Pointer The Cr(VI) reduction follows a pseudo first order kinetic with of salicylic acid. - Abstract: In this study, 64% of hexavalent chromium Cr(VI) reduction from the initial concentration (10{sup -4} M) is reported under visible light using the (CuAlO{sub 2}/CdS) hetero-system. In this new hetero-system, low doped CuAlO{sub 2} delafossite, synthesized by sol-gel works as an electrons reservoir with a wide space charge region (440 nm). In this case, the electron transfer to chromate is mediated via the hexagonal CdS variety, whose conduction band level is at -1.08 V with respect to the saturated calomel electrode which is more negative than the CrO{sub 4}{sup 2-}/Cr{sup 3+} level. This high reduction rate is achieved under optimized pH and CuAlO{sub 2} percentage. Moreover, salicylic acid gives the best performance among hole scavengers and CuAlO{sub 2} approaches 100% photostability at pH 7.5. The photo-catalytic process follows a pseudo first order kinetic with a half life of 2 h. The reaction products are identified by UV-visible spectrophotometry and linear voltametry at a platinum rotating electrode. The results reveal the presence of Cr{sup 3+} after irradiation.
Reduced Graphene Oxide-Immobilized Tris(bipyridine)ruthenium(II) Complex for Efficient Visible-Light-Driven Reductive Dehalogenation Reaction.

Science.gov (United States)

Li, Xiaoyan; Hao, Zhongkai; Zhang, Fang; Li, Hexing

2016-05-18

A sodium benzenesulfonate (PhSO3Na)-functionalized reduced graphene oxide was synthesized via a two-step aryl diazonium coupling and subsequent NaCl ion-exchange procedure, which was used as a support to immobilize tris(bipyridine)ruthenium(II) complex (Ru(bpy)3Cl2) by coordination reaction. This elaborated Ru(bpy)3-rGO catalyst exhibited excellent catalytic efficiency in visible-light-driven reductive dehalogenation reactions under mild conditions, even for ary chloride. Meanwhile, it showed the comparable reactivity with the corresponding homogeneous Ru(bpy)3Cl2 catalyst. This high catalytic performance could be attributed to the unique two-dimensional sheet-like structure of Ru(bpy)3-rGO, which efficiently diminished diffusion resistance of the reactants. Meanwhile, the nonconjugated PhSO3Na-linkage between Ru(II) complex and the support and the very low electrical conductivity of the catalyst inhibited energy/electron transfer from Ru(II) complex to rGO support, resulting in the decreased support-induced quenching effect. Furthermore, it could be easily recycled at least five times without significant loss of catalytic reactivity.
Enhanced selective photocatalytic reduction of CO2 to CH4 over plasmonic Au modified g-C3N4 photocatalyst under UV-vis light irradiation

Science.gov (United States)

Li, Hailong; Gao, Yan; Xiong, Zhuo; Liao, Chen; Shih, Kaimin

2018-05-01

A series of Au-g-C3N4 (Au-CN) catalysts were prepared through a NaBH4-reduction method using g-C3N4 (CN) from pyrolysis of urea as precursor. The catalysts' surface area, crystal structure, surface morphology, chemical state, functional group composition and optical properties were characterized by X-ray diffraction, transmission electron microscope, X-ray photoelectron spectroscopy, ultraviolet visible (UV-vis) diffuse reflectance spectra, fourier transform infrared, photoluminescence and transient photocurrent analysis. The carbon dioxide (CO2) photoreduction activities under ultraviolet visible (UV-vis) light irradiation were significantly enhanced when gold (Au) was loaded on the surface of CN. 2Au-CN catalyst with Au to CN mole ratio of 2% showed the best catalytic activity. After 2 h UV-vis light irradiation, the methane (CH4) yield over the 2Au-CN catalyst was 9.1 times higher than that over the pure CN. The CH4 selectivity also greatly improved for the 2Au-CN compared to the CN. The deposited Au nanoparticles facilitated the separation of electron-hole pairs on the CN surface. Moreover, the surface plasmon resonance effect of Au further promoted the generation of hot electrons and visible light absorption. Therefore, Au loading significantly improved CO2 photoreduction performance of CN under UV-vis light irradiation.
Reduced flight-to-light behaviour of moth populations exposed to long-term urban light pollution.

Science.gov (United States)

Altermatt, Florian; Ebert, Dieter

2016-04-01

The globally increasing light pollution is a well-recognized threat to ecosystems, with negative effects on human, animal and plant wellbeing. The most well-known and widely documented consequence of light pollution is the generally fatal attraction of nocturnal insects to artificial light sources. However, the evolutionary consequences are unknown. Here we report that moth populations from urban areas with high, globally relevant levels of light pollution over several decades show a significantly reduced flight-to-light behaviour compared with populations of the same species from pristine dark-sky habitats. Using a common garden setting, we reared moths from 10 different populations from early-instar larvae and experimentally compared their flight-to-light behaviour under standardized conditions. Moths from urban populations had a significant reduction in the flight-to-light behaviour compared with pristine populations. The reduced attraction to light sources of 'city moths' may directly increase these individuals' survival and reproduction. We anticipate that it comes with a reduced mobility, which negatively affects foraging as well as colonization ability. As nocturnal insects are of eminent significance as pollinators and the primary food source of many vertebrates, an evolutionary change of the flight-to-light behaviour thereby potentially cascades across species interaction networks. © 2016 The Author(s).
Increased stray gas abundance in a subset of drinking water wells near Marcellus shale gas extraction.

Science.gov (United States)

Jackson, Robert B; Vengosh, Avner; Darrah, Thomas H; Warner, Nathaniel R; Down, Adrian; Poreda, Robert J; Osborn, Stephen G; Zhao, Kaiguang; Karr, Jonathan D

2013-07-09

Horizontal drilling and hydraulic fracturing are transforming energy production, but their potential environmental effects remain controversial. We analyzed 141 drinking water wells across the Appalachian Plateaus physiographic province of northeastern Pennsylvania, examining natural gas concentrations and isotopic signatures with proximity to shale gas wells. Methane was detected in 82% of drinking water samples, with average concentrations six times higher for homes gas wells (P = 0.0006). Ethane was 23 times higher in homes gas wells (P = 0.0013); propane was detected in 10 water wells, all within approximately 1 km distance (P = 0.01). Of three factors previously proposed to influence gas concentrations in shallow groundwater (distances to gas wells, valley bottoms, and the Appalachian Structural Front, a proxy for tectonic deformation), distance to gas wells was highly significant for methane concentrations (P = 0.007; multiple regression), whereas distances to valley bottoms and the Appalachian Structural Front were not significant (P = 0.27 and P = 0.11, respectively). Distance to gas wells was also the most significant factor for Pearson and Spearman correlation analyses (P gas wells was the only statistically significant factor (P gas (4)He to CH4 in groundwater were characteristic of a thermally postmature Marcellus-like source in some cases. Overall, our data suggest that some homeowners living gas wells have drinking water contaminated with stray gases.
Energy Harvesting from the Stray Electromagnetic Field around the Electrical Power Cable for Smart Grid Applications.

Science.gov (United States)

Khan, Farid Ullah

For wireless sensor node (WSN) applications, this paper presents the harvesting of energy from the stray electromagnetic field around an electrical power line. Inductive and capacitive types of electrodynamic energy harvesters are developed and reported. For the produced energy harvesters, solid core and split-core designs are adopted. The inductive energy harvester comprises a copper wound coil which is produced on a mild steel core. However, the capacitive prototypes comprise parallel, annular discs separated by Teflon spacers. Moreover, for the inductive energy harvesters' wound coil and core, the parametric analysis is also performed. A Teflon housing is incorporated to protect the energy harvester prototypes from the harsh environmental conditions. Among the inductive energy harvesters, prototype-5 has performed better than the other harvesters and produces a maximum rms voltage of 908 mV at the current level of 155 A in the power line. However, at the same current flow, the capacitive energy harvesters produce a maximum rms voltage of 180 mV. The alternating output of the prototype-5 is rectified, and a super capacitor (1 F, 5.5 V) and rechargeable battery (Nickel-Cadmium, 3.8 V) are charged with it. Moreover, with the utilization of a prototype-5, a self-powered wireless temperature sensing and monitoring system for an electrical transformer is also developed and successfully implemented.
Determination of the Performance Parameters of a Spectrophotometer: An Advanced Experiment.

Science.gov (United States)

Cope, Virgil W.

1978-01-01

Describes an advanced analytical chemistry laboratory experiment developed for the determination of the performance parameters of a spectrophotometer. Among the parameters are the baseline linearity with wavelength, wavelength accuracy and respectability, stray light, noise level and pen response time. (HM)
Rapid thermal reduced graphene oxide/Pt–TiO2 nanotube arrays for enhanced visible-light-driven photocatalytic reduction of CO2

International Nuclear Information System (INIS)

Sim, Lan Ching; Leong, Kah Hon; Saravanan, Pichiah; Ibrahim, Shaliza

2015-01-01

Graphical abstract: - Highlights: • Enhanced visible light character of TNTs was imparted by RGO/Pt via facile route. • Pt NPs contribute exemplary visible light harvesting nature through plasmon effect. • Engulfed RGO promoted enhanced charge-carriers separation. • Synergistic effect of RGO, Pt photoreduced CO 2 to CH 4 with max. of 10.96 μmol m −2 . - Abstract: In this study, a complicate natural photosynthesis process was prototyped through a photocatalysis process by reducing CO 2 to light hydrocarbon, CH 4 . The composite photocatalyst employed for this study utilized Pt nanoparticles (Pt NPs) and rapid thermal reduced graphene oxide (RGO) deposited over the surface of the TiO 2 nanotube arrays (TNTs). The existence and contribution of both Pt NPs and RGO in the composite was confirmed through various analytical techniques including XRD, HRTEM, FESEM, Raman, FTIR, XPS, UV-DRS and photoluminescence (PL) analysis. The TNTs in the composite exhibited pure anatase phase. The absorption bands at around 450 nm obtained from UV-DRS spectrum supported the existence of LSPR phenomenon of Pt NPs. The promising lower work function of RGO promoted the electrons transfer from TNTs to RGO efficiently. The successful depositions of Pt and RGO onto the surface of TNTs contributed for the improved photocatalytic activity (total CH 4 yield of 10.96 μmol m −2 ) in the reduction of CO 2 over TNTs and Pt–TNTs. Both of RGO and Pt NPs are equally important to exert a significant impact on the improvement of CH 4 production rates.

Spot fat reduction by red and near infrared LED phototherapy

Science.gov (United States)

Lim, Sungkyoo; Park, Eal-Whan

2018-02-01

Low level light therapy (LLLT) using light from red and near infrared LEDs or Lasers have been reported effective as noninvasive methods for reducing spot fat. A total of 55 subjects were randomly divided into test groups and control groups for abdominal fat reduction clinical trial using red and near infrared LED phototherapy devices. Red and near infrared light with irradiance of 10 mW/cm2 were irradiated over the abdominal area to the test group for 30 minutes followed by 30 minutes of aerobic exercise, 3 times a week for 4 weeks. Control group used sham devices for 30 minutes and followed by 30 minutes of aerobic exercise. It is expected that red and near infrared LED phototherapy combined with aerobic exercise would be effective and safe for abdominal fat reduction without any side effects.
OVPD-processed OLED for general lighting

OpenAIRE

Bösing, Manuel

2012-01-01

Due to continuous advancements of materials for organic light emitting diodes (OLED) a new field of application currently opens up for OLED technology: General lighting. A significant reduction of OLED production cost might be achieved by employing organic vapor phase deposition (OVPD). OVPD is a novel process for depositing organic thin films from the gas phase. In contrast to the well established process of vacuum thermal evaporation (VTE), OVPD allows to achieve much higher deposition rate...
Light and lightened mirrors for astronomy

Science.gov (United States)

Fappani, Denis

2008-07-01

For ground-based astronomy, more and more large telescopes are emerging all around the world. Similarly to space borne telescopes, for which the use of lightened optics has always been a baseline for purpose of mass reduction of payloads, same kinds of lightened/light mirrors are then now more and more intensively used also for ground-based instrumentation for astronomy, requiring larger and larger components. Through several examples of typical past realizations (class 0.5m-1m) for different astronomical projects requiring light or lightened mirrors for different reasons (optimisation of mass and stiffness, reduction of thermal inertia, increasing of dynamic performance for fast scanning purpose,....), the presentation will point out issues for lightening design, manufacturing and control of such parts, as well as brief overview of the corresponding existing "state of the art" for these technologies in SESO.
Large Scale Reduction of Graphite Oxide Project

Science.gov (United States)

Calle, Carlos; Mackey, Paul; Falker, John; Zeitlin, Nancy

2015-01-01

This project seeks to develop an optical method to reduce graphite oxide into graphene efficiently and in larger formats than currently available. Current reduction methods are expensive, time-consuming or restricted to small, limited formats. Graphene has potential uses in ultracapacitors, energy storage, solar cells, flexible and light-weight circuits, touch screens, and chemical sensors. In addition, graphite oxide is a sustainable material that can be produced from any form of carbon, making this method environmentally friendly and adaptable for in-situ reduction.
Retinal protein synthesis in relationship to environmental lighting

International Nuclear Information System (INIS)

Hollyfield, J.G.; Anderson, R.E.

1982-01-01

A series of in vivo and in vitro experiments using Xenopus laevis juvenile toads was conducted to probe the relationship between environmental lighting and protein synthesis in the retina. Autoradiographic and biochemical analyses indicated that measurable changes in protein synthesis did not occur during a normal diurnal cycle when animals were conditioned to 12 hr light followed by 12 hr darkness each day (LD). However, when retinas from animals maintained in continuous darkness (DD) for 3 days were incubated with 3 H-leucine, there was a 40% reduction in the specific radioactivity of total retinal proteins compared with retinas from animals maintained in continuous light (LL) for 3 days or on the LD cycle. Retinas from DD animals injected with 3 H-leucine showed a 48% reduction in protein synthesis compared with retinas of LL animals. In autoradiographs of retinas from in vivo or in vitro experiments, grain counts were 40% lower in the total retinas of the DD animals compared with retinas of LL animals. This reduction occurred throughout the entire retina and was not restricted to any specific cell type. There was also a 35% reduction in the rate of radioactive band displacement in the rod outer segments of DD animals, although the percent of 3 H-leucine incorporated into opsin relative to total retinal protein was the same for both groups. We conclude from these studies that fluctuations in the rate of protein synthesis during the normal light-dark cycle are not detectable. However, major differences in protein synthesis are evident when animals are stressed with continuous darkness for several days. This effect is not restricted to any particular retinal layer but occurs throughout the entire retina. Moreover, prolonged darkness affects protein synthesis in extraocular tissues as well
Intercomparison of the LASCO-C2, SECCHI-COR1, SECCHI-COR2, and Mk4 Coronagraphs

Science.gov (United States)

Frazin, Richard A.; Vasquez, Alberto M.; Thompson, William T.; Hewett, Russell J.; Lamy, Philippe; Llebaria, Antoine; Vourlidas, Angelos; Burkepile, Joan

2012-01-01

In order to assess the reliability and consistency of white-light coronagraph measurements, we report on quantitative comparisons between polarized brightness [pB] and total brightness [B] images taken by the following white-light coronagraphs: LASCO-C2 on SOHO, SECCHI-COR1 and -COR2 on STEREO, and the ground-based MLSO-Mk4. The data for this comparison were taken on 16 April 2007, when both STEREO spacecraft were within 3.1 deg. of Earth’s heliographic longitude, affording essentially the same view of the Sun for all of the instruments. Due to the difficulties of estimating stray-light backgrounds in COR1 and COR2, only Mk4 and C2 produce reliable coronal-hole values (but not at overlapping heights), and these cannot be validated without rocket flights or ground-based eclipse measurements. Generally, the agreement between all of the instruments’ pB values is within the uncertainties in bright streamer structures, implying that measurements of bright CMEs also should be trustworthy. Dominant sources of uncertainty and stray light are discussed, as is the design of future coronagraphs from the perspective of the experiences with these instruments.
A triple spectrograph system for low stray light Thomson scattering measurements

NARCIS (Netherlands)

Sande, van de M.J.; Mullen, van der J.J.A.M.

2001-01-01

Thomson scattering is scattering of photons by the electrons in a plasma. From the scattering spectrum, the electron temperature and density (Te, ne) of the plasma can be deduced. In the past decade, the development of high power lasers and sensitive detection devices has made Thomson scattering a
VIBRATIONAL SPECTRA OF t-BUTYL ALCOHOL, t-BUTYLAMINE ...

African Journals Online (AJOL)

a

good stray light rejection. A Spectra-Physics ... the spectrometer. The vial was then spun to enhance the Raman signal and reduce the risk of .... *Abbreviations used: m, medium; s, strong; v, very; w, weak; sh, shoulder; -, not detected due to the ...
Induced Radioactivity in Lead Shielding at the National Synchrotron Light Source.

Science.gov (United States)

Ghosh, Vinita J; Schaefer, Charles; Kahnhauser, Henry

2017-06-01

The National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory was shut down in September 2014. Lead bricks used as radiological shadow shielding within the accelerator were exposed to stray radiation fields during normal operations. The FLUKA code, a fully integrated Monte Carlo simulation package for the interaction and transport of particles and nuclei in matter, was used to estimate induced radioactivity in this shielding and stainless steel beam pipe from known beam losses. The FLUKA output was processed using MICROSHIELD® to estimate on-contact exposure rates with individually exposed bricks to help design and optimize the radiological survey process. This entire process can be modeled using FLUKA, but use of MICROSHIELD® as a secondary method was chosen because of the project's resource constraints. Due to the compressed schedule and lack of shielding configuration data, simple FLUKA models were developed. FLUKA activity estimates for stainless steel were compared with sampling data to validate results, which show that simple FLUKA models and irradiation geometries can be used to predict radioactivity inventories accurately in exposed materials. During decommissioning 0.1% of the lead bricks were found to have measurable levels of induced radioactivity. Post-processing with MICROSHIELD® provides an acceptable secondary method of estimating residual exposure rates.
Geographic distribution of canine heartworm (Dirofilaria immitis infection in stray dogs of eastern Romania

Directory of Open Access Journals (Sweden)

Lavinia Ciucă

2016-11-01

Full Text Available A survey was conducted in the eastern part of Romania to assess the prevalence and geographical distribution of Dirofilaria immitis in dogs. Plasma samples were collected from 458 stray dogs hosted in shelters in 8 counties and tested serologically for the presence of heartworm. In addition, 45 blood samples from dogs of a shelter in Galati city were examined by the modified Knott and multiplex polymerase chain reaction (PCR techniques. The immmunological assay showed a heartworm infection prevalence of 8.9% in the dogs. Optical density results for positive samples ranged between 0.217 and 2.683. Geographical information systems (GIS were used to produce overlays of distribution maps of D. immitis prevalence and predictive maps based on temperature suitability. High prevalence of D. immitis was found in the central East up to the northern border of the country, i.e. Galati county (60%, followed by the counties of Vaslui (12.0% and Iasi (7.7%. Out of 45 samples examined using the Knott test, 23 were positive for circulating microfilariae (51.1%, while 19 dogs were positive for D. immitis and 4 for both D. immitis and D. repens with the multiplex PCR test. The high prevalence for D. immitis shown in dogs in the Southeast (Galati, 42.2% also by multiplex PCR gave strong support to the results achieved by the serological tests. The present study confirms the ability of GIS to predict the distribution and epidemiology of dirofilariosis in different geographical territories as has been already demonstrated by the empirical epidemiological data obtained at the continental, national and intraregional levels.
Bright light exposure reduces TH-positive dopamine neurons: implications of light pollution in Parkinson's disease epidemiology.

Science.gov (United States)

Romeo, Stefania; Viaggi, Cristina; Di Camillo, Daniela; Willis, Allison W; Lozzi, Luca; Rocchi, Cristina; Capannolo, Marta; Aloisi, Gabriella; Vaglini, Francesca; Maccarone, Rita; Caleo, Matteo; Missale, Cristina; Racette, Brad A; Corsini, Giovanni U; Maggio, Roberto

2013-01-01

This study explores the effect of continuous exposure to bright light on neuromelanin formation and dopamine neuron survival in the substantia nigra. Twenty-one days after birth, Sprague-Dawley albino rats were divided into groups and raised under different conditions of light exposure. At the end of the irradiation period, rats were sacrificed and assayed for neuromelanin formation and number of tyrosine hydroxylase (TH)-positive neurons in the substantia nigra. The rats exposed to bright light for 20 days or 90 days showed a relatively greater number of neuromelanin-positive neurons. Surprisingly, TH-positive neurons decreased progressively in the substantia nigra reaching a significant 29% reduction after 90 days of continuous bright light exposure. This decrease was paralleled by a diminution of dopamine and its metabolite in the striatum. Remarkably, in preliminary analysis that accounted for population density, the age and race adjusted Parkinson's disease prevalence significantly correlated with average satellite-observed sky light pollution.
DUV light source availability improvement via further enhancement of gas management technologies

Science.gov (United States)

Riggs, Daniel J.; O'Brien, Kevin; Brown, Daniel J. W.

2011-04-01

The continuous evolution of the semiconductor market necessitates ever-increasing improvements in DUV light source uptime as defined in the SEMI E10 standard. Cymer is developing technologies to exceed current and projected light source availability requirements via significant reduction in light source downtime. As an example, consider discharge chamber gas management functions which comprise a sizable portion of DUV light source downtime. Cymer's recent introduction of Gas Lifetime Extension (GLXTM) as a productivity improvement technology for its DUV lithography light sources has demonstrated noteworthy reduction in downtime. This has been achieved by reducing the frequency of full gas replenishment events from once per 100 million pulses to as low as once per 2 billion pulses. Cymer has continued to develop relevant technologies that target further reduction in downtime associated with light source gas management functions. Cymer's current subject is the development of technologies to reduce downtime associated with gas state optimization (e.g. total chamber gas pressure) and gas life duration. Current gas state optimization involves execution of a manual procedure at regular intervals throughout the lifetime of light source core components. Cymer aims to introduce a product enhancement - iGLXTM - that eliminates the need for the manual procedure and, further, achieves 4 billion pulse gas lives. Projections of uptime on DUV light sources indicate that downtime associated with gas management will be reduced by 70% when compared with GLX2. In addition to reducing downtime, iGLX reduces DUV light source cost of operation by constraining gas usage. Usage of fluorine rich Halogen gas mix has been reduced by 20% over GLX2.
Indications for chlororespiration in relation to light regime in the marine diatom Thalassiosira weissflogii.

Science.gov (United States)

Dijkman, Nicole A; Kroon, Bernd M A

2002-04-01

The marine diatom Thalassiosira weissflogii was cultured under a light regime simulating the daily rise and fall of the sun. The light regime caused a daily cycle in non-photochemical quenching. Remarkable were the changes in fluorescence directly after a light-to-dark transition that occurred in addition to the changes induced by non-photochemical quenching. A transient non-photochemical reduction of PQ and of Q(A) was indicated by a transient increase in apparent F(o) and by changes in the shape of the fluorescence induction curve. The observed changes developed approximately the first 100-120 s after a light-to-dark transition and could be reversed by the application of far-red illumination. Chlororespiration is thought to cause the reduction of PQ and, as the PQ-pool is in equilibrium with Q(A), also a reduction of Q(A). The function and ecological relevance of chlororespiration are discussed.
Lighting levels for isolated intersections : leading to safety improvements : final report.

Science.gov (United States)

2015-01-01

A number of studies have linked the benefits of roadway lighting to a reduction in crash rates at night for a variety : of roadway types including rural intersections. Assessing the effectiveness of intersection lighting has primarily : relied upon c...
Termination of light-water reactor core-melt accidents with a chemical core catcher: the core-melt source reduction system (COMSORS)

International Nuclear Information System (INIS)

Forsberg, C.W.; Parker, G.W.; Rudolph, J.C.; Osborne-Lee, I.W.; Kenton, M.A.

1996-09-01

The Core-Melt Source Reduction System (COMSORS) is a new approach to terminate light-water reactor core melt accidents and ensure containment integrity. A special dissolution glass is placed under the reactor vessel. If core debris is released onto the glass, the glass melts and the debris dissolves into the molten glass, thus creating a homogeneous molten glass. The molten glass, with dissolved core debris, spreads into a wide pool, distributing the heat for removal by radiation to the reactor cavity above or by transfer to water on top of the molten glass. Expected equilibrium glass temperatures are approximately 600 degrees C. The creation of a low-temperature, homogeneous molten glass with known geometry permits cooling of the glass without threatening containment integrity. This report describes the technology, initial experiments to measure key glass properties, and modeling of COMSORS operations
Effect of green light spectra on the reduction of retinal damage and stress in goldfish, Carassius auratus

International Nuclear Information System (INIS)

Song, Jin Ah; Kim, Na Na; Choi, Young Jae; Choi, Cheol Young

2016-01-01

We investigated the effect of light spectra on retinal damage and stress in goldfish using green (530 nm) and red (620 nm) light emitting diodes (LEDs) at three intensities each (0.5, 1.0, and 1.5 W/m"2). We measured the change in the levels of plasma cortisol and H_2O_2 and expression and levels of caspase-3. The apoptotic response of green and red LED spectra was assessed using the terminal transferase dUTP nick end labeling (TUNEL) assay. Stress indicator (cortisol and H_2O_2) and apoptosis-related genes (caspase-3) decreased in green light, but increased in red light with higher light intensities over time. The TUNEL assay revealed that more apoptotic cells were detected in outer nuclear layers after exposure to red LED over time with the increase in light intensity, than the other spectra. These results indicate that green light efficiently reduces retinal damage and stress, whereas red light induces it. Therefore, red light-induced retina damage may induce apoptosis in goldfish retina. -- Highlights: •Green light efficiently reduces retinal damage and stress. •Green spectra reduce caspase production and apoptosis. •Red light-induced retina damage may induce apoptosis in goldfish retina. •The retina of goldfish recognizes green spectra as a stable environment.
Effect of green light spectra on the reduction of retinal damage and stress in goldfish, Carassius auratus

Energy Technology Data Exchange (ETDEWEB)

Song, Jin Ah; Kim, Na Na; Choi, Young Jae; Choi, Cheol Young, E-mail: choic@kmou.ac.kr

2016-07-22

We investigated the effect of light spectra on retinal damage and stress in goldfish using green (530 nm) and red (620 nm) light emitting diodes (LEDs) at three intensities each (0.5, 1.0, and 1.5 W/m{sup 2}). We measured the change in the levels of plasma cortisol and H{sub 2}O{sub 2} and expression and levels of caspase-3. The apoptotic response of green and red LED spectra was assessed using the terminal transferase dUTP nick end labeling (TUNEL) assay. Stress indicator (cortisol and H{sub 2}O{sub 2}) and apoptosis-related genes (caspase-3) decreased in green light, but increased in red light with higher light intensities over time. The TUNEL assay revealed that more apoptotic cells were detected in outer nuclear layers after exposure to red LED over time with the increase in light intensity, than the other spectra. These results indicate that green light efficiently reduces retinal damage and stress, whereas red light induces it. Therefore, red light-induced retina damage may induce apoptosis in goldfish retina. -- Highlights: •Green light efficiently reduces retinal damage and stress. •Green spectra reduce caspase production and apoptosis. •Red light-induced retina damage may induce apoptosis in goldfish retina. •The retina of goldfish recognizes green spectra as a stable environment.
Prevalence of gastrointestinal parasites of stray dogs impounded by the Society for the Prevention of Cruelty to Animals (SPCA), Durban and Coast, South Africa.

Science.gov (United States)

Mukaratirwa, S; Singh, V P

2010-06-01

Coprological examination was used to determine the prevalence and intensity of gastrointestinal parasites of stray dogs impounded by the Society for the Prevention of Cruelty to Animals (SPCA), Durban and Coast, South Africa. Helminth and protozoan parasites were found in faeces of 240 dogs with an overall prevalence of 82.5% (helminth parasites 93.1% and protozoan parasites 6.9%). The following parasites and their prevalences were detected; Ancylostoma sp. (53.8%), Trichuris vulpis (7.9%), Spirocerca lupi (5.4%), Toxocara canis (7.9%), Toxascaris leonina (0.4%) Giardia intestinalis (5.6%) and Isospora sp. (1.3%). Dogs harbouring a single parasite species were more common (41.7%) than those harbouring 2 (15%) or multiple (2.1%) species. Ancylostoma sp., Toxocara canis and Giardia intestinalis have zoonotic potential and were detected in 66.7% of the samples.
Light pollution and solid-state lighting: reducing the carbon dioxide footprint is not enough

Science.gov (United States)

Bará, Salvador

2013-11-01

Public and private lighting account for a relevant share of the overall electric power consumption worldwide. The pressing need of reducing the carbon dioxide emissions as well as of lowering the lumen•hour price tag has fostered the search for alternative lighting technologies to substitute for the incandescent and gas-discharge based lamps. The most successful approach to date, solid-state lighting, is already finding its way into the public lighting market, very often helped by substantial public investments and support. LED-based sources have distinct advantages: under controlled coditions their efficacy equals or surpasses that of conventional solutions, their small source size allows for an efficient collimation of the lightbeam (delivering the photons where they are actually needed and reducing lightspill on the surrounding areas), and they can be switched and/or dimmed on demand at very high rates, thus allowing for a taylored schedule of lighting. However, energy savings and carbon dioxide reduction are not the only crucial issues faced by present day lighting. A growing body of research has shown the significance of the spectral composition of light when it comes to assess the detrimental effects of artificial light-at-night (ALAN). The potential ALAN blueshift associated to the deployment of LED-based lighting systems has raised sensible concerns about its scientific, cultural, ecological and public health consequences, which can be further amplified if an increased light consumption is produced due to the rebound effect. This contribution addresses some of the challenges that these issues pose to the Optics and Photonics community.
Ectoparasites in urban stray cats in Jerusalem, Israel: differences in infestation patterns of fleas, ticks and permanent ectoparasites.

Science.gov (United States)

Salant, H; Mumcuoglu, K Y; Baneth, G

2014-09-01

In a period cross-sectional study performed to examine ectoparasites on 340 stray cats in Jerusalem, Israel, 186 (54.7%) were infested with the cat flea, Ctenocephalides felis (Siphonaptera: Pulicidae), 49 (14.4%) with the cat louse, Felicola subrostratus (Phthiraptera: Trichodectidae), 41 (12.0%) with the ear mite, Otodectes cynotis (Astigmata: Psoroptidae), three (0.9%) with the fur mite, Cheyletiella blakei (Trobidiformes: Cheyletidae), two (0.6%) with the itch mite Notoedres cati (Astigmata: Sarcoptidae), and 25 (7.3%) with ticks of the species Rhipicephalus sanguineus sensu lato (Ixodida: Ixodidae), Rhipicephalus turanicus or Haemaphysalis adleri (Ixodida: Ixodidae). A higher number of flea infestations was observed in apparently sick cats (P < 0.05) and in cats aged < 6 months (P < 0.05). The proportion of flea-infested cats (P < 0.01), as well as the number of fleas per infested cat (P < 0.01), was higher in autumn than in other seasons. By contrast with findings in cats with flea infestations, rates of infestation with ticks were higher amongst cats with clinical signs (P < 0.01) and cats aged ≥ 6 months (P < 0.05). The high rates of ectoparasite infestation in the cats studied constitute a risk for the spread of vector-borne infections of zoonotic and veterinary importance. © 2013 The Royal Entomological Society.

Thomson scattering on non-equilibrium low density plasmas : principles, practice and challenges

NARCIS (Netherlands)

Carbone, E.A.D.; Nijdam, S.

2015-01-01

In this paper, we review the main challenges related to laser Thomson scattering on low temperature plasmas. The main features of the triple grating spectrometer used to discriminate Thomson and Raman scattering signals from Rayleigh scattering and stray light are presented. The main parameters
Towards the retrieval of tropospheric ozone with the ozone monitoring instrument (OMI)

NARCIS (Netherlands)

Mielonen, T.; De Haan, J.F.; Van Peet, J.C.A.; Eremenko, M.; Veefkind, J.P.

2015-01-01

We have assessed the sensitivity of the operational Ozone Monitoring Instrument (OMI) ozone profile retrieval algorithm to a number of a priori and radiative transfer assumptions. We studied the effect of stray light correction, surface albedo assumptions and a priori ozone profiles on the retrieved
Upgrade of the automatic analysis system in the TJ-II Thomson Scattering diagnostic: New image recognition classifier and fault condition detection

NARCIS (Netherlands)

Makili, L.; Vega, J.; Dormido-Canto, S.; Pastor, I.; Pereira, A.; Farias, G.; Portas, A.; Perez-Risco, D.; Rodriguez-Fernandez, M. C.; Busch, P.

2010-01-01

An automatic image classification system based on support vector machines (SVM) has been in operation for years in the TJ-II Thomson Scattering diagnostic. It recognizes five different types of images: CCD camera background, measurement of stray light without plasma or in a collapsed discharge,
Adjunctive dental therapy via tooth plaque reduction and gingivitis treatment by blue light-emitting diodes tooth brushing

Science.gov (United States)

Genina, Elina A.; Titorenko, Vladimir A.; Belikov, Andrey V.; Bashkatov, Alexey N.; Tuchin, Valery V.

2015-12-01

The efficacy of blue light-emitting toothbrushes (B-LETBs) (405 to 420 nm, power density 2 mW/cm2) for reduction of dental plaques and gingival inflammation has been evaluated. Microbiological study has shown the multifactor therapeutic action of the B-LETBs on oral pathological microflora: in addition to partial mechanical removal of bacteria, photodynamic action suppresses them up to 97.5%. In the pilot clinical studies, subjects with mild to moderate gingivitis have been randomly divided into two groups: a treatment group that used the B-LETBs and a control group that used standard toothbrushes. Indices of plaque, gingival bleeding, and inflammation have been evaluated. A significant improvement of all dental indices in comparison with the baseline (by 59%, 66%, and 82% for plaque, gingival bleeding, and inflammation, respectively) has been found. The treatment group has demonstrated up to 50% improvement relative to the control group. We have proposed the B-LETBs to serve for prevention of gingivitis or as an alternative to conventional antibiotic treatment of this disease due to their effectiveness and the absence of drug side effects and bacterial resistance.
Primary structure of the light-dependent regulatory site of corn NADP-malate dehydrogenase

Energy Technology Data Exchange (ETDEWEB)

Decottignies, P.; Schmitter, J.M.; Miginiac-Maslow, M.; Le Marechal, P.; Jacquot, J.P.; Gadal, P.

1988-08-25

The light-activated NADP-malate dehydrogenase (NADP-MDH) catalyzes the reduction of oxaloacetate to malate in higher plant chloroplasts. This enzyme is regulated in vivo by the ferredoxin-thioredoxin system through redox reactions. NADP-MDH has been photoactivated in vitro in a chloroplast system reconstituted from the pure protein components and thylakoid membranes. Photoactivation was accompanied by the appearance of new thiol groups (followed by (14C)iodoacetate incorporation). 14C-Carboxymethylated NADP-MDH has been purified from the incubation mixture and its amino-terminal sequence analyzed. Two (14C)carboxymethylcysteines were identified at positions 10 and 15 after light activation, while they were not detected in the dark-treated protein. In addition, the analysis of the tryptic digest of light-activated (14C)carboxymethylated NADP-MDH revealed that the radioactive label was mostly incorporated in Cys10 and Cys15, indicating that these 2 residues play a major role in the light activation mechanism. Moreover, an activation model, in which photoreduced thio-redoxin was replaced by the dithiol reductant dithio-threitol, has been developed. When NADP-MDH was activated in this way, the same sulfhydryls were found to be labeled, and alternatively, they did not incorporate any radioactivity when dithiothreitol reduction was performed after carboxymethylation in denaturating conditions. These results indicate that activation (by light or by dithiothreitol) proceeds on each subunit by reduction of a disulfide bridge located at the amino terminus of the enzyme between Cys10 and Cys15.
Primary structure of the light-dependent regulatory site of corn NADP-malate dehydrogenase

International Nuclear Information System (INIS)

Decottignies, P.; Schmitter, J.M.; Miginiac-Maslow, M.; Le Marechal, P.; Jacquot, J.P.; Gadal, P.

1988-01-01

The light-activated NADP-malate dehydrogenase (NADP-MDH) catalyzes the reduction of oxaloacetate to malate in higher plant chloroplasts. This enzyme is regulated in vivo by the ferredoxin-thioredoxin system through redox reactions. NADP-MDH has been photoactivated in vitro in a chloroplast system reconstituted from the pure protein components and thylakoid membranes. Photoactivation was accompanied by the appearance of new thiol groups (followed by [14C]iodoacetate incorporation). 14C-Carboxymethylated NADP-MDH has been purified from the incubation mixture and its amino-terminal sequence analyzed. Two [14C]carboxymethylcysteines were identified at positions 10 and 15 after light activation, while they were not detected in the dark-treated protein. In addition, the analysis of the tryptic digest of light-activated [14C]carboxymethylated NADP-MDH revealed that the radioactive label was mostly incorporated in Cys10 and Cys15, indicating that these 2 residues play a major role in the light activation mechanism. Moreover, an activation model, in which photoreduced thio-redoxin was replaced by the dithiol reductant dithio-threitol, has been developed. When NADP-MDH was activated in this way, the same sulfhydryls were found to be labeled, and alternatively, they did not incorporate any radioactivity when dithiothreitol reduction was performed after carboxymethylation in denaturating conditions. These results indicate that activation (by light or by dithiothreitol) proceeds on each subunit by reduction of a disulfide bridge located at the amino terminus of the enzyme between Cys10 and Cys15
Effect of disposable infection control barriers on light output from dental curing lights.

Science.gov (United States)

Scott, Barbara A; Felix, Corey A; Price, Richard B T

2004-02-01

To prevent contamination of the light guide on a dental curing light, barriers such as disposable plastic wrap or covers may be used. This study compared the effect of 3 disposable barriers on the spectral output and power density from a curing light. The hypothesis was that none of the barriers would have a significant clinical effect on the spectral output or the power density from the curing light. Three disposable barriers were tested against a control (no barrier). The spectra and power from the curing light were measured with a spectrometer attached to an integrating sphere. The measurements were repeated on 10 separate occasions in a random sequence for each barrier. Analysis of variance (ANOVA) followed by Fisher's protected least significant difference test showed that the power density was significantly less than control (by 2.4% to 6.1%) when 2 commercially available disposable barriers were used (p 0.05). The effect of each of the barriers on the power output was small and probably clinically insignificant. ANOVA comparisons of mean peak wavelength values indicated that none of the barriers produced a significant shift in the spectral output relative to the control ( p > 0.05). Two of the 3 disposable barriers produced a significant reduction in power density from the curing light. This drop in power was small and would probably not adversely affect the curing of composite resin. None of the barriers acted as light filters.
Blue light inhibits the growth of B16 melanoma cells

International Nuclear Information System (INIS)

Ohara, Masayuki; Katoh, Osamu; Watanabe, Hiromitsu

2002-01-01

Although a number of studies have been carried out to examine the biological effects of radiation and ultraviolet radiation (UV), little is known concerning the effects of visible light. In the present study, exposure of B16 melanoma cells to blue light (wavelength 470 nm, irradiance 5.7 mW/cm 2 ) from a light-emitting diode (LED) inhibited cell growth in proportion to the period of exposure, with no increase observed in the number of dead cells. The number of B16 melanoma colonies that formed after exposure to blue light for 20 min was only slightly less than that in non-exposed controls, but the colony size as assessed by the area covered by colonies and cell counts per colony were markedly decreased. The percentages of G0/G1 and G2/M phase cells were markedly increased, with a reduction in S phase cells as determined by flow cytometry after exposure to blue light. Furthermore, analysis of the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into DNA also showed a reduction in the percentage of S phase cells after exposure. These results indicate that blue light exerts cytostatic effects, but not a cytocidal action, on B16 melanoma cells. (author)
Blue light inhibits the growth of B16 melanoma cells

Energy Technology Data Exchange (ETDEWEB)

Ohara, Masayuki; Katoh, Osamu; Watanabe, Hiromitsu [Hiroshima Univ. (Japan). Research Inst. for Radiation Biology and Medicine; Kawashima, Yuzo [Otsuka Pharmaceutical Factory, Inc., Naruto, Tokushima (Japan)

2002-05-01

Although a number of studies have been carried out to examine the biological effects of radiation and ultraviolet radiation (UV), little is known concerning the effects of visible light. In the present study, exposure of B16 melanoma cells to blue light (wavelength 470 nm, irradiance 5.7 mW/cm{sup 2}) from a light-emitting diode (LED) inhibited cell growth in proportion to the period of exposure, with no increase observed in the number of dead cells. The number of B16 melanoma colonies that formed after exposure to blue light for 20 min was only slightly less than that in non-exposed controls, but the colony size as assessed by the area covered by colonies and cell counts per colony were markedly decreased. The percentages of G0/G1 and G2/M phase cells were markedly increased, with a reduction in S phase cells as determined by flow cytometry after exposure to blue light. Furthermore, analysis of the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into DNA also showed a reduction in the percentage of S phase cells after exposure. These results indicate that blue light exerts cytostatic effects, but not a cytocidal action, on B16 melanoma cells. (author)
Cost-Benefit Analysis and Emission Reduction of Energy Efficient Lighting at the Universiti Tenaga Nasional

Science.gov (United States)

Ganandran, G. S. B.; Mahlia, T. M. I.; Ong, Hwai Chyuan; Rismanchi, B.; Chong, W. T.

2014-01-01

This paper reports the result of an investigation on the potential energy saving of the lighting systems at selected buildings of the Universiti Tenaga Nasional. The scope of this project includes evaluation of the lighting system in the Library, Admin Building, College of Engineering, College of Information Technology, Apartments, and COE Food court of the university. The main objectives of this project are to design the proper retrofit scenario and to calculate the potential electricity saving, the payback period, and the potential environmental benefits. In this survey the policy for retrofitting the old lighting system with the new energy saving LEDs starts with 10% for the first year and continues constantly for 10 years until all the lighting systems have been replaced. The result of the life cycle analysis reveals that after four years, the selected buildings will bring profit for the investment. PMID:25133258
Cost-Benefit Analysis and Emission Reduction of Energy Efficient Lighting at the Universiti Tenaga Nasional

Directory of Open Access Journals (Sweden)

G. S. B. Ganandran

2014-01-01

Full Text Available This paper reports the result of an investigation on the potential energy saving of the lighting systems at selected buildings of the Universiti Tenaga Nasional. The scope of this project includes evaluation of the lighting system in the Library, Admin Building, College of Engineering, College of Information Technology, Apartments, and COE Food court of the university. The main objectives of this project are to design the proper retrofit scenario and to calculate the potential electricity saving, the payback period, and the potential environmental benefits. In this survey the policy for retrofitting the old lighting system with the new energy saving LEDs starts with 10% for the first year and continues constantly for 10 years until all the lighting systems have been replaced. The result of the life cycle analysis reveals that after four years, the selected buildings will bring profit for the investment.
Energy savings due to daylight and artificial lighting integration in office buildings in hot climate

Energy Technology Data Exchange (ETDEWEB)

Al-Ashwal, Nagib T. [Sana' a University, Sana' a (Yemen); Budaiwi, Ismail M. [King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia)

2011-07-01

Reducing energy consumption while maintaining acceptable environmental quality in buildings has been a challenging task for building professionals. In office buildings, artificial lighting systems are a major consumer of energy and can significantly contribute to building cooling load. Furthermore, although reliable, artificial lighting does not necessarily provide the required quality of lighting. Significant improvement in lighting quality and energy consumption can be achieved by proper integration of daylight and artificial lighting. The objective of this study is to investigate the energy performance of office buildings resulting from daylight and artificial lighting integration in hot climates. A parametric analysis is conducted to find the impact of different window design parameters, including window area, height and glazing type, on building energy performance. Results have shown that as much as 35% reduction in lighting energy consumption and 13% reduction in total energy consumption can be obtained when proper daylighting and artificial lighting integration is achieved.
Total site integration of light hydrocarbons separation process

OpenAIRE

Ulyev, L.; Vasilyev, M.; Maatouk, A.; Duic, Neven; Khusanovc, Alisher

2016-01-01

Ukraine is the largest consumer of hydrocarbons per unit of production in Europe (Ukraine policy review, 2006). The most important point is a reduction of energy consumption in chemical and metallurgical industries as a biggest consumer. This paper deals with energy savings potential of light hydrocarbons separation process. Energy consumption of light hydrocarbons separation process processes typical of Eastern European countries were analysed. Process Integration (PI) was used to perform a ...
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.
The roles of specific xanthophylls in light utilization.

Science.gov (United States)

Kalituho, Ljudmila; Rech, Jennifer; Jahns, Peter

2007-01-01

To evaluate the role of specific xanthophylls in light utilization, wild-type and xanthophyll mutant plants (npq1, npq2, lut2, lut2npq1 and lut2npq2) from Arabidopsis thaliana were grown under three different light regimes: 30 (low light, LL), 150 (medium light, ML) and 450 (high light, HL) mumol photons m(-2) s(-1). We studied the pigment content, growth rate, xanthophyll cycle activity, chlorophyll fluorescence parameters and the response to photoinhibition. All genotypes differed strongly in the growth rates and the resistance against photoinhibition. In particular, replacement of lutein (Lut) by violaxanthin (Vx) in the lut2npq1 mutant did not affect the growth at non-saturating light intensities (LL and ML), but led to a pronounced reduction of growth under HL conditions, indicating an important photoprotective role of Lut. This was further supported by a much higher sensitivity of all Lut-deficient plants to photoinhibition in comparison with the wild type. In contrast, replacement of Lut by zeaxanthin (Zx) in lut2npq2 led to a pronounced reduction of growth under all light regimes, most likely related to the permanent non-photochemical dissipation of excitation energy by Zx at Vx-binding sites and the destabilization of antenna proteins by binding of Zx to Lut-binding sites. The high susceptibility of lut2npq2 to photoinhibition in comparison with npq2 further indicated that the photoprotective function of Zx is abolished in the absence of Lut. Thus, it can be concluded from our work that neither Vx nor Zx is able to fulfil the essential photoprotective function at Lut-binding sites under in vivo conditions.
Reduction of chromium (VI) on the hetero-system CuBi2O4/TiO2 under solar light

Science.gov (United States)

Lahmar, H.; Benamira, M.; Akika, F. Z.; Trari, M.

2017-11-01

The CuBi2O4/TiO2 heterojunction was tested with success for the photo-catalytic reduction of chromate ions under sunlight. CuBi2O4, prepared by nitrate process, was characterised photo-electrochemically. The oxide is stable against photo corrosion by consumption of holes in presence of oxalic acid. The light absorption promotes electrons in the conduction band of the sensitizer (CuBi2O4) with a very negative potential (-1.74 VSCE) to participate in the exchange of the electron with HCrO4-. The enhanced activity is due to electron injection of activated CuBi2O4 into TiO2-CB (-0.97 VSCE). The band gap of the semiconductor CuBi2O4 is 1.50 eV with a direct optical transition. This compound is a p-type semiconductor with a flat band potential of -0.39 VSCE and activation energy of 0.18 eV. The electrochemical impedance spectroscopy was undertaken to study the semiconductor/electrolyte interfacial phenomena. The photoactivity on the heterojunction is strongly enhanced. A remarkable performance is obtained in less than 4 h for a concentration of 30 mg in (Cr (VI)) at pH ∼ 4 and a dose of 1 mg/mL; a 98% reduction has been obtained. The kinetic of chromate photoreduction is well described by the Langmuir-Hinshelwood model. The chromate elimination obeys to a pseudo-first order kinetic with an apparent rate constant of 0.014 min-1.
Pole masses of quarks in dimensional reduction

International Nuclear Information System (INIS)

Avdeev, L.V.; Kalmykov, M.Yu.

1997-01-01

Pole masses of quarks in quantum chromodynamics are calculated to the two-loop order in the framework of the regularization by dimensional reduction. For the diagram with a light quark loop, the non-Euclidean asymptotic expansion is constructed with the external momentum on the mass shell of a heavy quark
Dynamic Camouflage in Benthic and Pelagic Cephalopods: An Interdisciplinary Approach to Crypsis Based on Color, Reflection, and Bioluminescence

Science.gov (United States)

2012-09-30

cruise. 4 Figure 1: Hatchling cuttlefish on a dynamic background of varying intensities and spatial frequencies. The background changed in...captured as a reflectance map . A pinhole aperture is used to block light from off-axis sample points and stray light. The available range for both...image processing techniques (figure 8) to determine the variability and the areas of change in individual animal responses a) over an hour period on
Vertically aligned carbon nanotubes black coatings from roll-to-roll deposition process

Science.gov (United States)

Goislard de Monsabert, Thomas; Papciak, L.; Sangar, A.; Descarpentries, J.; Vignal, T.; de Longiviere, Xavier; Porterat, D.; Mestre, Q.; Hauf, H.

2017-09-01

Vertically aligned carbon nanotubes (VACNTs) have recently attracted growing interest as a very efficient light absorbing material over a broad spectral range making them a superior coating in space optics applications such as radiometry, optical calibration, and stray light elimination. However, VACNT coatings available to-date most often result from batch-to-batch deposition processes thus potentially limiting the manufacturing repeatability, substrate size and cost efficiency of this material.
Proton radiation effects on the optical properties of vertically aligned carbon nanotubes

Science.gov (United States)

Kuhnhenn, J.; Khavrus, V.; Leonhardt, A.; Eversheim, D.; Noll, C.; Hinderlich, S.; Dahl, A.

2017-11-01

This paper discusses proton-induced radiation effects in vertically aligned carbon nanotubes (VA-CNT). VACNTs exhibit extremely low optical reflectivity which makes them interesting candidates for use in spacecraft stray light suppression. Investigating their behavior in space environment is a precondition for the implementation on a satellite.

Thomson scattering using an atomic notch filter

NARCIS (Netherlands)

Bakker, L.P.; Freriks, J.M.; Hoog, de F.J.; Kroesen, G.M.W.

2000-01-01

One of the biggest problems in performing Thomson scattering experiments in low-density plasmas is the very high stray light intensity in comparison with the Thomson scattering intensity. This problem is especially present in fluorescent lamps because of the proximity of the glass tube. We propose
Dose reduction at nuclear power plants

International Nuclear Information System (INIS)

Baum, J.W.; Dionne, B.J.

1983-01-01

The collective dose equivalent at nuclear power plants increased from 1250 rem in 1969 to nearly 54,000 rem in 1980. This rise is attributable primarily to an increase in nuclear generated power from 1289 MW-y to 29,155 MW-y; and secondly, to increased average plant age. However, considerable variation in exposure occurs from plant to plant depending on plant type, refueling, maintenance, etc. In order to understand the factors influencing these differences, an investigation was initiated to study dose-reduction techniques and effectiveness of as low as reasonably achievable (ALARA) planning at light water plants. Objectives are to: identify high-dose maintenance tasks and related dose-reduction techniques; investigate utilization of high-reliability, low-maintenance equipment; recommend improved radioactive waste handling equipment and procedures; examine incentives for dose reduction; and compile an ALARA handbook
Evaluating the Impacts of Red Light Camera Deployment on Intersection Traffic Safety

Science.gov (United States)

2018-06-01

Red-light cameras (RLC) are a popular countermeasure to reduce red-light running and improve intersection safety. Studies show that the reduction in side impact crashes at RLC intersections are often accompanied by no-change or an increase in the num...
Iterative noise removal from temperature and density profiles in the TJ-II Thomson scattering

International Nuclear Information System (INIS)

Farias, G.; Dormido-Canto, S.; Vega, J.; Santos, M.; Pastor, I.; Fingerhuth, S.; Ascencio, J.

2014-01-01

TJ-II Thomson Scattering diagnostic provides temperature and density profiles of plasma. The CCD camera acquires images that are corrupted with some kind of noise called stray-light. This noise degrades both image contrast and measurement accuracy, which could produce unreliable profiles of the diagnostic. So far, several approaches have been applied in order to decrease the noise in the TJ-II Thomson scattering images. Since the presence of the noise is not global but located in some particular regions of the image, advanced processing techniques are needed. However such methods require of manual fine-tuning of parameters to reach a good performance. In this contribution, an iterative image processing approach is applied in order to reduce the stray light effects in the images of the TJ-II Thomson scattering diagnostic. The proposed solution describes how the noise can be iteratively reduced in the images when a key parameter is automatically adjusted during the iterative process
Iterative noise removal from temperature and density profiles in the TJ-II Thomson scattering

Energy Technology Data Exchange (ETDEWEB)

Farias, G., E-mail: gonzalo.farias@ucv.cl [Pontificia Universidad Católica de Valparaíso, Av. Brasil 2147, Valparaíso (Chile); Dormido-Canto, S., E-mail: sebas@dia.uned.es [Departamento de Informática y Automática, UNED, 28040 Madrid (Spain); Vega, J., E-mail: jesus.vega@ciemat.es [Asociación EURATOM/CIEMAT para Fusión, Avd. Complutense 22, 28040 Madrid (Spain); Santos, M., E-mail: msantos@ucm.es [Departamento de Arquitectura de Computadores y Automática, Universidad Complutense de Madrid, 28040 Madrid (Spain); Pastor, I., E-mail: ignacio.pastor@ciemat.es [Asociación EURATOM/CIEMAT para Fusión, Avd. Complutense 22, 28040 Madrid (Spain); Fingerhuth, S., E-mail: sebastian.fingerhuth@ucv.cl [Pontificia Universidad Católica de Valparaíso, Av. Brasil 2147, Valparaíso (Chile); Ascencio, J., E-mail: j_ascencio21@hotmail.com [Pontificia Universidad Católica de Valparaíso, Av. Brasil 2147, Valparaíso (Chile)

2014-05-15

TJ-II Thomson Scattering diagnostic provides temperature and density profiles of plasma. The CCD camera acquires images that are corrupted with some kind of noise called stray-light. This noise degrades both image contrast and measurement accuracy, which could produce unreliable profiles of the diagnostic. So far, several approaches have been applied in order to decrease the noise in the TJ-II Thomson scattering images. Since the presence of the noise is not global but located in some particular regions of the image, advanced processing techniques are needed. However such methods require of manual fine-tuning of parameters to reach a good performance. In this contribution, an iterative image processing approach is applied in order to reduce the stray light effects in the images of the TJ-II Thomson scattering diagnostic. The proposed solution describes how the noise can be iteratively reduced in the images when a key parameter is automatically adjusted during the iterative process.
Low-temperature fabrication and characterization of a symmetric hybrid organic–inorganic slab waveguide for evanescent light microscopy

Science.gov (United States)

Agnarsson, Björn; Mapar, Mokhtar; Sjöberg, Mattias; Alizadehheidari, Mohammadreza; Höök, Fredrik

2018-06-01

Organic and inorganic solid materials form the building blocks for most of today’s high-technological instruments and devices. However, challenges related to dissimilar material properties have hampered the synthesis of thin-film devices comprised of both organic and inorganic films. We here give a detailed description of a carefully optimized processing protocol used for the construction of a three-layered hybrid organic–inorganic waveguide-chip intended for combined scattering and fluorescence evanescent-wave microscopy in aqueous environments using conventional upright microscopes. An inorganic core layer (SiO2 or Si3N4), embedded symmetrically in an organic cladding layer (CYTOP), aids simple, yet efficient in-coupling of light, and since the organic cladding layer is refractive index matched to water, low stray-light (background) scattering of the propagating light is ensured. Another major advantage is that the inorganic core layer makes the chip compatible with multiple well-established surface functionalization schemes that allows for a broad range of applications, including detection of single lipid vesicles, metallic nanoparticles or cells in complex environments, either label-free—by direct detection of scattered light—or by use of fluorescence excitation and emission. Herein, focus is put on a detailed description of the fabrication of the waveguide-chip, together with a fundamental characterization of its optical properties and performance, particularly in comparison with conventional epi illumination. Quantitative analysis of images obtained from both fluorescence and scattering intensities from surface-immobilized polystyrene nanoparticles in suspensions of different concentrations, revealed enhanced signal-to-noise and signal-to-background ratios for the waveguide illumination compared to the epi-illumination.
Reduction of minor actinides for recycling in a light water reactor

International Nuclear Information System (INIS)

Martinez C, E.; Ramirez S, J. R.; Alonso V, G.

2015-09-01

The aim of actinide transmutation from spent nuclear fuel is the reduction in mass of high-level waste which must be stored in geological repositories and the lifetime of high-level waste; these two achievements will reduce the number of repositories needed, as well as the duration of storage. The present work is directed towards the evaluation of an advanced nuclear fuel cycle in which the minor actinides (Np, Am and Cm) could be recycled to remove most of the radioactive material; a reference of actinides production in standard nuclear fuel of uranium at the end of its burning in a BWR is first established, after a design of fuel rod containing 6% of minor actinides in a matrix of uranium from the enrichment lines is proposed, then 4 fuel rods of standard uranium are replaced by 4 actinides bars to evaluate the production and transmutation of them and finally the minor actinides reduction in the fuel is evaluated. In the development of this work the calculation tool are the codes: Intrepin-3, Casmo-4 and Simulate-3. (Author)
Energy efficient solid state lighting

Energy Technology Data Exchange (ETDEWEB)

Dam-Hansen, C.; Petersen, Poul Michael

2012-11-15

Even though vast improvements have been made on efficiency and light quality, SSL is still in its infancy. One of the barriers for a market introduction is the price, which still is around 5 times higher than traditional lighting technologies. In order to fulfil the potential of SSL, further research and development needs to increase the light extraction from semiconductor materials, provide better and cheaper production and packaging, and advanced optical systems for optimized light distribution and new thermal solutions for SSL lamps and luminaires. Nanotechnology and applied research at DTU Fotonik in close collaboration with industry are essential parts in the development of new enhanced LED optical systems and LEDs with higher light extraction efficiency. Photonic crystals can help to efficiently extract light from LEDs and to form a desired emission profile. Future directions are devoted to the next generation of LEDs, in which the spontaneous emission is photon enhanced. One realization of this idea is using LEDs with a layer of nanocrystals, which are coupled to the quantum well of the LED. Such R and D work is ongoing all over the world and DOE roadmaps foresee luminous efficiencies by 2020 that are close to 250 lm/W for both cold and warm white light from LEDs, and prices in the order of one dollar per kilolumen. Such figures will drastically reduce the energy consumption worldwide for lighting, and hence a marked reduction in carbon emissions. (Author)
Structural slow light can enhance Beer-Lambert absorption

OpenAIRE

Dicaire Isabelle; Chin Sanghoon; Thévenaz Luc

2011-01-01

We experimentally demonstrate that structural slow light can enhance Beer-Lambert absorption. A 4-fold reduction of the group velocity induced by mere cavity effects has caused an increase of molecular absorption by 130%.
Light Sources and Lighting Circuits

Science.gov (United States)

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

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

Science.gov (United States)

Bergman, Keren

Optical fibers offer considerable advantages over bulk nonlinear media for the generation of squeezed states. This thesis reports on experimental investigations of reducing quantum noise by means of squeezing in nonlinear fiber optic interferometers. Fibers have low insertion loss which allows for long interaction lengths. High field intensities are easily achieved in the small cores of single mode fibers. Additionally, the nonlinear process employed is self phase modulation or the Kerr effect, whose broad band nature requires no phase matching and can be exploited with ultra-short pulses of high peak intensity. All these advantageous features of fibers result in easily obtained large nonlinear phase shifts and subsequently large squeezing parameters. By the self phase modulation process a correlation is produced between the phase and amplitude fluctuations of the optical field. The attenuated or squeezed quadrature has a lower noise level than the initial level associated with the coherent state field before propagation. The resulting reduced quantum noise quadrature can be utilized to improve the sensitivity of a phase measuring instrument such as an interferometer. Because the Kerr nonlinearity is a degenerate self pumping process, the squeezed noise is at the same frequency as the pump field. Classical pump noise can therefore interfere with the desired measurement of the quantum noise reduction. The most severe noise process is the phase noise caused by thermally induced index modulation of the fiber. This noise termed Guided Acoustic Wave Brillouin Scattering, or GAWBS, by previous researchers is studied and analyzed. Experiments performed to overcome GAWBS successfully with several schemes are described. An experimental demonstration of an interferometric measurement with better sensitivity than the standard quantum limit is described. The results lead to new understandings into the limitations of quantum noise reduction that can be achieved in the
Session IV. Problem Solving. Vehicle lighting system. Four steps in glare reduction.

NARCIS (Netherlands)

Schreuder, D.A.

1972-01-01

A number of proposals are described that may help to reduce glare. The systems are either only a partial improvement, or they are expensive, or their introduction raises severe problems. One solution, already widely in use, is applica- tion of overhead lighting. In order to really improve the
Solar glint suppression in compact planetary ultraviolet spectrographs

Science.gov (United States)

Davis, Michael W.; Cook, Jason C.; Grava, Cesare; Greathouse, Thomas K.; Gladstone, G. Randall; Retherford, Kurt D.

2015-08-01

Solar glint suppression is an important consideration in the design of compact photon-counting ultraviolet spectrographs. Southwest Research Institute developed the Lyman Alpha Mapping Project for the Lunar Reconnaissance Orbiter (launch in 2009), and the Ultraviolet Spectrograph on Juno (Juno-UVS, launch in 2011). Both of these compact spectrographs revealed minor solar glints in flight that did not appear in pre-launch analyses. These glints only appeared when their respective spacecraft were operating outside primary science mission parameters. Post-facto scattered light analysis verifies the geometries at which these glints occurred and why they were not caught during ground testing or nominal mission operations. The limitations of standard baffle design at near-grazing angles are discussed, as well as the importance of including surface scatter properties in standard stray light analyses when determining solar keep-out efficiency. In particular, the scattered light analysis of these two instruments shows that standard "one bounce" assumptions in baffle design are not always enough to prevent scattered sunlight from reaching the instrument focal plane. Future builds, such as JUICE-UVS, will implement improved scattered and stray light modeling early in the design phase to enhance capabilities in extended mission science phases, as well as optimize solar keep out volume.
Low Light Availability Alters Root Exudation and Reduces Putative Beneficial Microorganisms in Seagrass Roots

Directory of Open Access Journals (Sweden)

Belinda C. Martin

2018-01-01

Full Text Available Seagrass roots host a diverse microbiome that is critical for plant growth and health. Composition of microbial communities can be regulated in part by root exudates, but the specifics of these interactions in seagrass rhizospheres are still largely unknown. As light availability controls primary productivity, reduced light may impact root exudation and consequently the composition of the root microbiome. Hence, we analyzed the influence of light availability on root exudation and community structure of the root microbiome of three co-occurring seagrass species, Halophila ovalis, Halodule uninervis and Cymodocea serrulata. Plants were grown under four light treatments in mesocosms for 2 weeks; control (100% surface irradiance (SI, medium (40% SI, low (20% SI and fluctuating light (10 days 20% and 4 days 100%. 16S rDNA amplicon sequencing revealed that microbial diversity, composition and predicted function were strongly influenced by the presence of seagrass roots, such that root microbiomes were unique to each seagrass species. Reduced light availability altered seagrass root exudation, as characterized using fluorescence spectroscopy, and altered the composition of seagrass root microbiomes with a reduction in abundance of potentially beneficial microorganisms. Overall, this study highlights the potential for above-ground light reduction to invoke a cascade of changes from alterations in root exudation to a reduction in putative beneficial microorganisms and, ultimately, confirms the importance of the seagrass root environment – a critical, but often overlooked space.
Facile Synthesis of g-C3N4 Nanosheets/ZnO Nanocomposites with Enhanced Photocatalytic Activity in Reduction of Aqueous Chromium(VI under Visible Light

Directory of Open Access Journals (Sweden)

Xiaoya Yuan

2016-09-01

Full Text Available Graphitic-C3N4 nanosheets (CN/ZnO photocatalysts (CN/ZnO with different CN loadings were successfully prepared via a simple precipitation-calcination in the presence of exfoliated C3N4 nanosheets. Their morphology and structure were thoroughly characterized by powder X-ray diffraction (XRD, scanning electron microscopy (SEM, high-resolution transmission electron microscopy (HRTEM, X-ray photoelectron spectroscopy (XPS, UV-Vis diffuse reflectance spectroscopy (DRS and photoluminescence spectra (PL. The results showed that hexagonal wurzite-phase ZnO nanoparticles were randomly distributed onto the CN nanosheets with a well-bonded interface between the two components in the CN/ZnO composites. The performance of the photocatalytic Cr(VI reduction indicated that CN/ZnO exhibited better photocatalytic activity than pure ZnO under visible-light irradiation and the photocatalyst composite with a lower loading of CN sheets eventually displayed higher activity. The enhanced performance of CN/ZnO photocatalysts could be ascribed to the increased absorption of the visible light and the effective transfer and separation of the photogenerated charge carriers.
Procedure for calibrating the Technicon Colorimeter I.

Science.gov (United States)

Black, J C; Furman, W B

1975-05-01

We describe a rapid method for calibrating the Technicon AutoAnalyzer colorimeter I. Test solutions of bromphenol blue are recommended for the calibration, in preference to solutions of potassium dichromate, based on considerations of the instrument's working range and of the stray light characteristics of the associated filters.
Highly efficient blazed grating with multilayer coating for tender X-ray energies

NARCIS (Netherlands)

Senf, F.; Bijkerk, Frederik; Eggenstein, F.; Gwalt, G.; Huang, Qiushi; van de Kruijs, Robbert Wilhelmus Elisabeth; Kutz, O.; Lemke, S.; Louis, Eric; Mertin, M.; Packe, I.; Rudolph, I.; Schafers, F.; Siewert, F.; Sokolov, A.; Sturm, Jacobus Marinus; Waberski, C.; Wang, Z.; Wolf, J.; Zeschke, T.; Erko, A.

2016-01-01

For photon energies of 1 – 5 keV, blazed gratings with multilayer coating are ideally suited for the suppression of stray and higher orders light in grating monochromators. We developed and characterized a blazed 2000 lines/mm grating coated with a 20 period Cr/C- multilayer. The multilayer
Sensitivity of the OMI ozone profile retrieval (OMO3PR) to a priori assumptions

NARCIS (Netherlands)

Mielonen, T.; De Haan, J.F.; Veefkind, J.P.

2014-01-01

We have assessed the sensitivity of the operational OMI ozone profile retrieval (OMO3PR) algorithm to a number of a priori assumptions. We studied the effect of stray light correction, surface albedo assumptions and a priori ozone profiles on the retrieved ozone profile. Then, we studied how to
Paths to light trapping in thin film GaAs solar cells.

Science.gov (United States)

Xiao, Jianling; Fang, Hanlin; Su, Rongbin; Li, Kezheng; Song, Jindong; Krauss, Thomas F; Li, Juntao; Martins, Emiliano R

2018-03-19

It is now well established that light trapping is an essential element of thin film solar cell design. Numerous light trapping geometries have already been applied to thin film cells, especially to silicon-based devices. Less attention has been paid to light trapping in GaAs thin film cells, mainly because light trapping is considered less attractive due to the material's direct bandgap and the fact that GaAs suffers from strong surface recombination, which particularly affects etched nanostructures. Here, we study light trapping structures that are implemented in a high-bandgap material on the back of the GaAs active layer, thereby not perturbing the integrity of the GaAs active layer. We study photonic crystal and quasi-random nanostructures both by simulation and by experiment and find that the photonic crystal structures are superior because they exhibit fewer but stronger resonances that are better matched to the narrow wavelength range where GaAs benefits from light trapping. In fact, we show that a 1500 nm thick cell with photonic crystals achieves the same short circuit current as an unpatterned 4000 nm thick cell. These findings are significant because they afford a sizeable reduction in active layer thickness, and therefore a reduction in expensive epitaxial growth time and cost, yet without compromising performance.
The At-Wavelength Metrology Facility at BESSY-II

Directory of Open Access Journals (Sweden)

Franz Schäfers

2016-02-01

Full Text Available The At-Wavelength Metrology Facility at BESSY-II is dedicated to short-term characterization of novel UV, EUV and XUV optical elements, such as diffraction gratings, mirrors, multilayers and nano-optical devices like reflection zone plates. It consists of an Optics Beamline PM-1 and a Reflectometer in a clean-room hutch as a fixed end station. The bending magnet Beamline is a Plane Grating Monochromator beamline (c-PGM equipped with an SX700 monochromator. The beamline is specially tailored for efficient high-order suppression and stray light reduction. The versatile 11-axes UHV-Reflectometer can house life-sized optical elements, which are fully adjustable and of which the reflection properties can be measured in the full incidence angular range as well as in the full azimuthal angular range to determine polarization properties.

Light history modulates antioxidant and photosynthetic responses of biofilms to both natural (light) and chemical (herbicides) stressors.

Science.gov (United States)

Bonnineau, Chloé; Sague, Irene Gallardo; Urrea, Gemma; Guasch, Helena

2012-05-01

In multiple stress situations, the co-occurrence of environmental and chemical factors can influence organisms' ability to cope with toxicity. In this context, the influence of light adaptation on the response of freshwater biofilms to sudden light changes or to herbicides exposure was investigated by determining various parameters: diatom community composition, photosynthetic parameters, chlorophyll a content, antioxidant enzyme activities. Biofilms were grown in microcosms under sub-optimal, saturating, and high light intensities and showed already described characteristics of shade/light adaptation (community structure, photosynthetic adaptation, etc.). Light history modulated antioxidant and photosynthetic responses of biofilms to the stress caused by short-term exposure to sudden light changes or to herbicides. First biofilms adapted to sub-optimal light intensity (shade-adapted) were found to be more sensitive to an increase in light intensity than high-light adapted ones to a reduction in light intensity. Second, while light history influenced biofilms' response to glyphosate, it had little influence on biofilms' response to copper and none on its response to oxyfluorfen. Indeed glyphosate exposure led to a stronger decrease in photosynthetic efficiency of shade-adapted biofilms (EC(50) = 11.7 mg L(-1)) than of high-light adapted communities (EC(50) = 35.6 mg L(-1)). Copper exposure led to an activation of ascorbate peroxidase (APX) in biofilms adapted to sub-optimal and saturating light intensity while the protein content decreased in all biofilms exposed to copper. Oxyfluorfen toxicity was independent of light history provoking an increase in APX activity. In conclusion this study showed that both previous exposure to contaminants and physical habitat characteristics might influence community tolerance to disturbances strongly.
Analysis of stray radiation produced by the advanced light source (1.9 GeV synchrotron radiation source) at Lawrence Berkeley Laboratory

Energy Technology Data Exchange (ETDEWEB)

Ajemian, Robert C. [Univ. of North Carolina, Chapel Hill, NC (United States). Dept. of Environmental Sciences and Engineering

1995-01-01

The yearly environmental dose equivalent likely to result at the closest site boundary from the Advanced Light Source was determined by generating multiple linear regressions. The independent variables comprised quantified accelerator operating parameters and measurements from synchronized, in-close (outside shielding prior to significant atmospheric scattering), state-of-the-art neutron remmeters and photon G-M tubes. Neutron regression models were more successful than photon models due to lower relative background radiation and redundant detectors at the site boundary. As expected, Storage Ring Beam Fill and Beam Crashes produced radiation at a higher rate than gradual Beam Decay; however, only the latter did not include zero in its 95% confidence interval. By summing for all three accelerator operating modes, a combined yearly DE of 4.3 mRem/yr with a 90% CI of (0.04-8.63) was obtained. These results fall below the DOE reporting level of 10 mRem/yr and suggest repeating the study with improved experimental conditions.
Analysis of stray radiation produced by the advanced light source (1.9 GeV synchrotron radiation source) at Lawrence Berkeley Laboratory

International Nuclear Information System (INIS)

Ajemian, R.C.

1995-01-01

The yearly environmental dose equivalent likely to result at the closest site boundary from the Advanced Light Source was determined by generating multiple linear regressions. The independent variables comprised quantified accelerator operating parameters and measurements from synchronized, in-close (outside shielding prior to significant atmospheric scattering), state-of-the-art neutron remmeters and photon G-M tubes. Neutron regression models were more successful than photon models due to lower relative background radiation and redundant detectors at the site boundary. As expected, Storage Ring Beam Fill and Beam Crashes produced radiation at a higher rate than gradual Beam Decay; however, only the latter did not include zero in its 95% confidence interval. By summing for all three accelerator operating modes, a combined yearly DE of 4.3 mRem/yr with a 90% CI of (0.04-8.63) was obtained. These results fall below the DOE reporting level of 10 mRem/yr and suggest repeating the study with improved experimental conditions
Speckle noise reduction on a laser projection display via a broadband green light source.

Science.gov (United States)

Yu, Nan Ei; Choi, Ju Won; Kang, Heejong; Ko, Do-Kyeong; Fu, Shih-Hao; Liou, Jiun-Wei; Kung, Andy H; Choi, Hee Joo; Kim, Byoung Joo; Cha, Myoungsik; Peng, Lung-Han

2014-02-10

A broadband green light source was demonstrated using a tandem-poled lithium niobate (TPLN) crystal. The measured wavelength and temperature bandwidth were 6.5 nm and 100 °C, respectively, spectral bandwidth was 36 times broader than the periodically poled case. Although the conversion efficiency was smaller than in the periodic case, the TPLN device had a good figure of merit owing to the extremely large bandwidth for wavelength and temperature. The developed broadband green light source exhibited speckle noise approximately one-seventh of that in the conventional approach for a laser projection display.
Robust binding between carbon nitride nanosheets and a binuclear ruthenium(II) complex enabling durable, selective CO{sub 2} reduction under visible light in aqueous solution

Energy Technology Data Exchange (ETDEWEB)

Kuriki, Ryo; Ishitani, Osamu; Maeda, Kazuhiko [Department of Chemistry, School of Science, Tokyo Institute of Technology (Japan); Yamamoto, Muneaki; Yoshida, Tomoko [Advanced Research Institute for Natural Science and Technology, Osaka City University (Japan); Higuchi, Kimitaka; Yamamoto, Yuta; Akatsuka, Masato; Yagi, Shinya [Institute of Materials and Systems for Sustainability, Nagoya University (Japan); Lu, Daling [Suzukakedai Materials Analysis Division, Technical Department, Tokyo Institute of Technology, Yokohama (Japan)

2017-04-18

Carbon nitride nanosheets (NS-C{sub 3}N{sub 4}) were found to undergo robust binding with a binuclear ruthenium(II) complex (RuRu') even in basic aqueous solution. A hybrid material consisting of NS-C{sub 3}N{sub 4} (further modified with nanoparticulate Ag) and RuRu' promoted the photocatalytic reduction of CO{sub 2} to formate in aqueous media, in conjunction with high selectivity (approximately 98 %) and a good turnover number (>2000 with respect to the loaded Ru complex). These represent the highest values yet reported for a powder-based photocatalytic system during CO{sub 2} reduction under visible light in an aqueous environment. We also assessed the desorption of RuRu' from the Ag/C{sub 3}N{sub 4} surface, a factor that can contribute to a loss of activity. It was determined that desorption is not induced by salt additives, pH changes, or photoirradiation, which partly explains the high photocatalytic performance of this material. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)
Prevalence of gastrointestinal parasites of stray dogs impounded by the Society for the Prevention of Cruelty to Animals (SPCA, Durban and Coast, South Africa : short communication

Directory of Open Access Journals (Sweden)

S. Mukaratirwa

2010-05-01

Full Text Available Coprological examination was used to determine the prevalence and intensity of gastrointestinal parasites of stray dogs impounded by the Society for the Prevention of Cruelty to Animals (SPCA, Durban and Coast, South Africa. Helminth and protozoan parasites were found in faeces of 240 dogs with an overall prevalence of 82.5% (helminth parasites 93.1% and protozoan parasites 6.9 %. The following parasites and their prevalences were detected; Ancylostoma sp. (53.8 %, Trichuris vulpis (7.9 %, Spirocerca lupi (5.4 %, Toxocara canis (7.9 %, Toxascaris leonina (0.4 % Giardia intestinalis (5.6 % and Isospora sp. (1.3 %. Dogs harbouring a single parasite species were more common (41.7 % than those harbouring 2 (15 % or multiple (2.1 % species. Ancylostoma sp., Toxocara canis and Giardia intestinalis have zoonotic potential and were detected in 66.7 % of the samples.
The Progression of Circadian Phase during Light Exposure in Animals and Humans

NARCIS (Netherlands)

Beersma, Domien G. M.; Comas, Marian; Hut, Roelof A.; Gordijn, Marijke C. M.; Rueger, Melanie; Daan, Serge

Studies in humans and mice revealed that circadian phase shifting effects of light are larger at the beginning of a light exposure interval than during subsequent exposure. Little is known about the dynamics of this response reduction phenomenon. Here the authors propose a method to obtain
Thomson scattering measurements on an atmospheric Ar dc discharge lamp

NARCIS (Netherlands)

Zhu, Xiao-Yan; Redwitz, M.; Kieft, E.R.; Sande, van de M.J.; Mullen, van der J.J.A.M.

2004-01-01

Thomson scattering (TS) experiments have been performed in the region near the electrodes of a dc powered model lamp filled with 1-2 bar argon gas. In order to suppress the false stray light and Rayleigh scattered photons, a triple grating spectrograph was used. In this way the electron density and
Preparation of CdS@CeO{sub 2} core/shell composite for photocatalytic reduction of CO{sub 2} under visible-light irradiation

Energy Technology Data Exchange (ETDEWEB)

Ijaz, Sana [CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190 (China); Institute of Chemical Sciences, Bahauddin Zakaryia University, Multan 60800 (Pakistan); Ehsan, Muhammad Fahad [CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190 (China); Ashiq, Muhammad Naeem, E-mail: naeemashiqqau@yahoo.com [Institute of Chemical Sciences, Bahauddin Zakaryia University, Multan 60800 (Pakistan); Karamat, Nazia [Institute of Chemical Sciences, Bahauddin Zakaryia University, Multan 60800 (Pakistan); He, Tao, E-mail: het@nanoctr.cn [CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190 (China); University of Chinese Academy of Sciences, Beijing 100049 (China)

2016-12-30

Highlights: • CdS@CeO{sub 2}core(*)/shell composite is fabricated using a two-step method. • CdS@CeO{sub 2} can photoreduce CO{sub 2} into CH{sub 4} and CH{sub 3}OH under visible-light irradiation. • CdS@CeO{sub 2} can enhance photocatalytic activity due to increased charge separation. • Core shell strategy for photocatalyst preparation can improve photostability. - Abstract: Present work demonstrates fabrication of CdS@CeO{sub 2} core/shell composite and its application in the photocatalytic reduction of CO{sub 2} under visible-light irradiation (λ ≥ 420 nm). CdS@CeO{sub 2} composite has been successfully prepared by two-step chemical method, while CeO{sub 2} and CdS have been synthesized by one-step hydrothermal method. X-ray diffraction analysis confirms the formation of fluorite cubic structure of CeO{sub 2} and cubic phase of CdS. High resolution transmission electron microscopy and scanning electron microscopy reveal the microsphere morphology of CdS, while CeO{sub 2} (shell) is in the form of spherical particles that surround the CdS (core) in case of the composite. X-ray photoelectron spectroscopy has been used to confirm the composition, oxidation state of the elements and valance band of the obtained materials. The CdS@CeO{sub 2} core/shell composite and CdS can convert CO{sub 2} into methane and methanol under visible-light irradiation. The CdS@CeO{sub 2} composite shows higher yield for both methane and methanol than CdS due to low recombination rate of photogenerated electron/hole pairs, as well as a larger BET specific surface area. Moreover, the CdS@CeO{sub 2} core/shell composite also shows improved stability upon photocatalysis.
Stray current induced corrosion in lightning rod cables of 525 kV power lines towers: a case study

Directory of Open Access Journals (Sweden)

Wojcicki, F. R.

2003-12-01

Full Text Available With the growth of several areas in modem society, the necessity to generate and carry electrical energy to big cities has greatly increased. Cables supported by power towers with galvanized steel foundation usually carry energy. As the foundations are underground they may cause high rates of corrosion. These are usually detected by a conventional potential measurement using a Cu/CuSO₄ reference electrode. It is believed that corrosion results from stray currents that flow through the ground to close the loop between neighboring towers. Stray currents originate in the lightning rod cables of the power line towers, induced by the strong electromagnetic and electric fields of the energized power lines. The intensity and direction of those currents were measured, indicating substantial values of both their AC and DC components. The potential of the tower ground system, measured in the perpendicular direction of the main axis of the power line, was plotted as a function of the distance to the tower base. The results clearly indicated the tendency to corrosive attack in the anodic towers as reflected by the slope of the plot, whereas no signs of corrosion could be found in the reverse slope, confirming the visual inspection of the foundation. The profile of the potential plots could be changed providing the electric insulation of the lightning rod cable.

Con el crecimiento de varias áreas en la sociedad moderna, la necesidad de generar y conducir la energía eléctrica a las grandes ciudades ha aumentado enormemente. La energía, normalmente, se transporta por cables sostenidos por torres de energía con base de acero galvanizado. Cuando las bases son subterráneas, pueden ocasionar altas tasas de corrosión. Estas, normalmente, se detectan por la medida convencional del potencial empleando un electrodo de referencia de Cu/CuSO₄. Se cree que la corrosión es el resultado de corrientes perdidas que fluyen a través de la
Metal organic framework g-C3N4/MIL-53(Fe) heterojunctions with enhanced photocatalytic activity for Cr(VI) reduction under visible light

Science.gov (United States)

Huang, Wenyuan; Liu, Ning; Zhang, Xiaodong; Wu, Minghong; Tang, Liang

2017-12-01

In this study, hybrid nanocomposites based on Fe-based MOF and graphitic carbon nitride (g-C3N4) were developed by a facile solvothermal method. The as-prepared materials were characterized by XRD, FESEM, TEM, XPS and PL analysis. It was showed that the introduction of a certain amount of g-C3N4 on the surface of MIL-53(Fe) would improve the separation and migration rate of photo-induced charges, consequently resulting in the boost of photocatalytic efficiency. Compared with g-C3N4 and MIL-53(Fe), the CMFe composites displayed more excellent visible light-resposive photocatalytic activity for the reduction of Cr(VI). The optimal doping content of g-C3N4 in g-C3N4/MIL-53(Fe) composite was determined to be 3.0 wt%, and it showed about 2.1 and 2.0 times as high photocatalytic efficiency for the reduction of Cr(VI) as that of pure g-C3N4 and MIL-53(Fe), respectively. Meanwhile, the composite exhibited good reusability and stability in the process of cyclic experiments. A possible photocatalytic reaction mechanism was also investigated in detail by the related electrochemical analysis.
Rapid thermal reduced graphene oxide/Pt–TiO{sub 2} nanotube arrays for enhanced visible-light-driven photocatalytic reduction of CO{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Sim, Lan Ching [Environmental Engineering Laboratory, Department of Civil Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Faculty of Engineering and Green Technology, Universiti Tunku Abdul Rahman, Jalan Universiti, Bandar Barat, 31900 Kampar, Perak (Malaysia); Leong, Kah Hon [Environmental Engineering Laboratory, Department of Civil Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Saravanan, Pichiah, E-mail: saravananpichiah@um.edu.my [Environmental Engineering Laboratory, Department of Civil Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Nanotechnology & Catalysis Research Center (NANOCAT), University of Malaya, 50603 Kuala Lumpur (Malaysia); Ibrahim, Shaliza [Environmental Engineering Laboratory, Department of Civil Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia)

2015-12-15

Graphical abstract: - Highlights: • Enhanced visible light character of TNTs was imparted by RGO/Pt via facile route. • Pt NPs contribute exemplary visible light harvesting nature through plasmon effect. • Engulfed RGO promoted enhanced charge-carriers separation. • Synergistic effect of RGO, Pt photoreduced CO{sub 2} to CH{sub 4} with max. of 10.96 μmol m{sup −2}. - Abstract: In this study, a complicate natural photosynthesis process was prototyped through a photocatalysis process by reducing CO{sub 2} to light hydrocarbon, CH{sub 4}. The composite photocatalyst employed for this study utilized Pt nanoparticles (Pt NPs) and rapid thermal reduced graphene oxide (RGO) deposited over the surface of the TiO{sub 2} nanotube arrays (TNTs). The existence and contribution of both Pt NPs and RGO in the composite was confirmed through various analytical techniques including XRD, HRTEM, FESEM, Raman, FTIR, XPS, UV-DRS and photoluminescence (PL) analysis. The TNTs in the composite exhibited pure anatase phase. The absorption bands at around 450 nm obtained from UV-DRS spectrum supported the existence of LSPR phenomenon of Pt NPs. The promising lower work function of RGO promoted the electrons transfer from TNTs to RGO efficiently. The successful depositions of Pt and RGO onto the surface of TNTs contributed for the improved photocatalytic activity (total CH{sub 4} yield of 10.96 μmol m{sup −2}) in the reduction of CO{sub 2} over TNTs and Pt–TNTs. Both of RGO and Pt NPs are equally important to exert a significant impact on the improvement of CH{sub 4} production rates.
Facilitation of decommissioning light water reactors

International Nuclear Information System (INIS)

Moore, E.B. Jr.

1979-12-01

Information on design features, special equipment, and construction methods useful in the facilitation of decommissioning light water reactors is presented. A wide range of facilitation methods - from improved documentation to special decommissioning tools and techniques - is discussed. In addition, estimates of capital costs, cost savings, and radiation dose reduction associated with these facilitation methods are given
Reduction of chromatic aberration influences in vertical scanning white-light interferometry

International Nuclear Information System (INIS)

Lehmann, Peter; Kühnhold, Peter; Xie, Weichang

2014-01-01

Vertical scanning white-light interferometry (SWLI) is a well-established method that is widely used in high precision surface topography measurement. However, SWLI results show characteristic slope-dependent errors due to dispersion effects and lateral chromatic aberrations of the optical imaging system. In this paper, we present methods to characterize these systematic errors related to dispersion and lateral colour. Lateral colour leads to field-dependent systematic discrepancies of the topography data obtained from the envelope position of a low-coherence interference signal and the data resulting from its interference phase. Hence, an erroneous fringe order obtained from the envelope position leads to a 2π phase jump and thus to a so-called ghost step in the measured topography. Our first approach to solve this problem is based on the measurement of a surface standard of well-known geometry. By comparison of measurement results related to the envelope position and the phase of SWLI signals, the systematic error is estimated and a numerical error compensation method is proposed. Both experimental and simulation results confirm the validity of this numerical method. In addition, using an improved design of a white-light Michelson interferometer we demonstrate experimentally that lateral chromatic aberrations and dispersion influences can be reduced also in a physical way. In this context, a conventional long working distance microscope objective is used which was not originally designed for a Michelson interference microscope. (paper)
Observational artifacts of Nuclear Spectroscopic Telescope Array: Ghost rays and stray light

DEFF Research Database (Denmark)

Madsen, Kristin K.; Christensen, Finn Erland; Craig, William W.

2017-01-01

photons that do not undergo the focused double reflections in the optics, and we term these ghost rays. We present detailed analysis and characterization of these two components and discuss how they impact observations. Finally, we discuss how they could have been prevented and should be in future...
Manipulating light with strongly modulated photonic crystals

International Nuclear Information System (INIS)

Notomi, Masaya

2010-01-01

Recently, strongly modulated photonic crystals, fabricated by the state-of-the-art semiconductor nanofabrication process, have realized various novel optical properties. This paper describes the way in which they differ from other optical media, and clarifies what they can do. In particular, three important issues are considered: light confinement, frequency dispersion and spatial dispersion. First, I describe the latest status and impact of ultra-strong light confinement in a wavelength-cubic volume achieved in photonic crystals. Second, the extreme reduction in the speed of light is reported, which was achieved as a result of frequency dispersion management. Third, strange negative refraction in photonic crystals is introduced, which results from their unique spatial dispersion, and it is clarified how this leads to perfect imaging. The last two sections are devoted to applications of these novel properties. First, I report the fact that strong light confinement and huge light-matter interaction enhancement make strongly modulated photonic crystals promising for on-chip all-optical processing, and present several examples including all-optical switches/memories and optical logics. As a second application, it is shown that the strong light confinement and slow light in strongly modulated photonic crystals enable the adiabatic tuning of light, which leads to various novel ways of controlling light, such as adiabatic frequency conversion, efficient optomechanics systems, photon memories and photons pinning.
Image processing and data reduction of Apollo low light level photographs

Science.gov (United States)

Alvord, G. C.

1975-01-01

The removal of the lens induced vignetting from a selected sample of the Apollo low light level photographs is discussed. The methods used were developed earlier. A study of the effect of noise on vignetting removal and the comparability of the Apollo 35mm Nikon lens vignetting was also undertaken. The vignetting removal was successful to about 10% photometry, and noise has a severe effect on the useful photometric output data. Separate vignetting functions must be used for different flights since the vignetting function varies from camera to camera in size and shape.
Electrical Parasitics and Thermal Modeling for Optimized Layout Design of High Power SiC Modules

DEFF Research Database (Denmark)

Bahman, Amir Sajjad; Blaabjerg, Frede; Dutta, Atanu

2016-01-01

, the presented models are verified by a conventional and an optimized power module layout. The optimized layout is designed based on the reduction of stray inductance and temperature in a P-cell and N-cell half-bridge module. The presented models are verified by FEM simulations and also experiment....
Testing and Characterization of a Prototype Telescope for the Evolved Laser Interferometer Space Antenna (eLISA)

Science.gov (United States)

Sankar, S.; Livas, J.

2016-01-01

We describe our efforts to fabricate, test and characterize a prototype telescope for the eLISA mission. Much of our work has centered on the modeling and measurement of scattered light performance. This work also builds on a previous demonstration of a high dimensional stability metering structure using particular choices of materials and interfaces. We will discuss ongoing plans to merge these two separate demonstrations into a single telescope design demonstrating both stray light and dimensional stability requirements simultaneously.
Measuring the Contribution of Atmospheric Scatter to Laser Eye Dazzle

Science.gov (United States)

2015-09-01

lasers; (140.3360) Laser safety and eye protection; (290.5820) Scattering measurements; (330.4060) Vision modeling; (330.4595) Optical effects on... vision . http://dx.doi.org/10.1364/A0.54.007567 1. INTRODUCTION Laser eye dazzle is the temporary visual obscurat ion caused by visible wavelength laser...2003). 6. P. Padmos, “Glare and tunnel entrance lighting: effects of stray light from eye, atmosphere and windscreen,” CIE J. 3, 1–24 (1984). 7. W. C

Visible-Light-Responsive Catalyst Development for Volatile Organic Carbon Remediation

Data.gov (United States)

National Aeronautics and Space Administration — Photocatalysis is a process in which light energy is used to ‘activate’ oxidation/reduction reactions. Unmodified titanium dioxide (TiO2), a common photocatalyst,...
Quantum mechanics and faster-than-light communication: methodological considerations

International Nuclear Information System (INIS)

Ghirardi, G.C.; Weber, T.

1983-06-01

A detailed quantum mechanical analysis of a recent proposal of faster than light communication through wave packet reduction is performed. The discussion allows us to focus on some methodological problems about critical investigations in physical theories. (author)
Photo-induced reduction of flavin mononucleotide in aqueous solutions

International Nuclear Information System (INIS)

Song, S.-H.; Dick, B.; Penzkofer, A.

2007-01-01

The photo-induced reduction of flavin mononucleotide (FMN) in aqueous solutions is studied by absorption spectra measurement under aerobic and anaerobic conditions. Samples without exogenous reducing agent and with the exogenous reducing agents ethylene-diamine-tetraacetic acid (EDTA) and dithiothreitol (DTT) are investigated. Under anaerobic conditions the photo-induced reduction with and without reducing agents is irreversible. Under aerobic conditions the photo-reduction without added reducing agent is small compared to the photo-degradation, and the photo-reduction of FMN by the reducing agents is reversible (re-oxidation in the dark). During photo-excitation of FMN the dissolved oxygen is consumed by singlet oxygen formation and subsequent chemical reaction. After light switch-off slow re-oxidation (slow absorption recovery) occurs due to air in-diffusion from surface. EDTA degradation by FMN excitation leads to oxygen scavenging. The quantum efficiencies of photo-reduction under aerobic and anaerobic conditions are determined. The re-oxidation of reduced FMN under aerobic conditions and due to air injection is investigated
Images of Light - Is phasing out the solution?

DEFF Research Database (Denmark)

Jensen, Charlotte Louise; Remmen, Arne

2012-01-01

approximately 20% of the world’s total energy consumption was consumed by lighting (Brown, 2010) which calls for attention to how energy consumption from lighting may be reduced. A strategy for phasing out the worst-performing light bulbs for domestic use is included in the European Ecodesign directive (2005......Due to a combination of reasons such as climate change, peak oil, security, etc., especially EU and several national governments have an increased focus on a transformation of the current energy systems through reduction of energy consumption and increased use of renewable energy sources.In 2005....../32/EC), constantly raising the performance standards. Various lighting technologies are now on the market, however with fluctuating quality, which, among other things, affect the rate households adopting new technologies (Krantz and Bladh, 2008) (Wall and Crosbie, 2009). However, aspects such as culture...
Selective disulfide reduction for labeling and enhancement of Fab antibody fragments.

Science.gov (United States)

Kirley, Terence L; Greis, Kenneth D; Norman, Andrew B

2016-11-25

Many methods have been developed for chemical labeling and enhancement of the properties of antibodies and their common fragments, including the Fab and F(ab') 2 fragments. Somewhat selective reduction of some antibody disulfide bonds has been previously achieved, yielding antibodies and antibody fragments that can be labeled at defined sites, enhancing their utility and properties. Selective reduction of the two hinge disulfide bonds present in F(ab') 2 fragments using mild reduction has been useful. However, such reduction is often not quantitative and results in the reduction of multiple disulfide bonds, and therefore subsequent multiple labeling or conjugation sites are neither homogenous nor stoichiometric. Here, a simple and efficient selective reduction of the single disulfide bond linking the partial heavy chain and the intact light chain which compose the Fab fragment is accomplished utilizing tris(2-carboxyethyl)phosphine (TCEP) immobilized on agarose beads. The resultant reduced cysteine residues were labeled with several cysteine-selective fluorescent reagents, as well as by cysteine-directed PEGylation. These two cysteine residues can also be re-ligated by means of a bifunctional cysteine cross-linking agent, dibromobimane, thereby both restoring a covalent linkage between the heavy and light chains at this site, far removed from the antigen binding site, and also introducing a fluorescent probe. There are many other research and clinical uses for these selectively partially reduced Fab fragments, including biotinylation, toxin and drug conjugation, and incorporation of radioisotopes, and this technique enables simple generation of very useful Fab fragment derivatives with many potential applications. Copyright © 2016 Elsevier Inc. All rights reserved.
Lighting in the shackling area: conciliating broiler welfare with labor comfort

Directory of Open Access Journals (Sweden)

GO Adamczuk

2014-06-01

Full Text Available The objective of this study was to investigate if blue lighting could reduce broiler stress and comply with legal labor comfort requirements in a new shackling area of a middle-size processing plant. In this study, the old shackling area was compared with the new area, where a blue lighting system was designed and implemented according to the regulations. The old and new areas were video- and audio-recorded during the shackling of 33,850 broilers in each area. Data were statistically analyzed using the non-parametric test of Wilcoxon-Mann-Whitney (w test.The results indicated 56% reduction in wing-flapping and 3.2% noise reduction in the new area. These results were obtained by increasing 119% lighting at the work stations in the shackling area, allowing workers to handle the birds more carefully, which may improve processing plant productivity. The study demonstrated that it is possible to conciliate better animal welfare with visual comfort for workers in the shackling area.
Upgrade of the Automatic Analysis System in the TJ-II Thomson Scattering Diagnostic: New Image Recognition Classifier and Fault Condition Detection

Energy Technology Data Exchange (ETDEWEB)

Makili, L.; Dormido-Canto, S. [UNED, Madrid (Spain); Vega, J.; Pastor, I.; Pereira, A.; Portas, A.; Perez-Risco, D.; Rodriguez-Fernandez, M. [Association EuratomCIEMAT para Fusion, Madrid (Spain); Busch, P. [FOM Instituut voor PlasmaFysica Rijnhuizen, Nieuwegein (Netherlands)

2009-07-01

Full text of publication follows: An automatic image classification system has been in operation for years in the TJ-II Thomson diagnostic. It recognizes five different types of images: CCD camera background, measurement of stray light without plasma or in a collapsed discharge, image during ECH phase, image during NBI phase and image after reaching the cut o density during ECH heating. Each kind of image implies the execution of different application software. Therefore, the classification system was developed to launch the corresponding software in an automatic way. The method to recognize the several classes was based on a learning system, in particular Support Vector Machines (SVM). Since the first implementation of the classifier, a relevant improvement has been accomplished in the diagnostic: a new notch filter is in operation, having a larger stray-light rejection at the ruby wavelength than the previous filter. On the other hand, its location in the optical system has been modified. As a consequence, the stray light pattern in the CCD image is located in a different position. In addition to these transformations, the power of neutral beams injected in the TJ-II plasma has been increased about a factor of 2. Due to the fact that the recognition system is based on a learning system and major modifications have been carried out in both the diagnostic (optics) and TJ-II plasmas (injected power), the classifier model is no longer valid. The creation of a new model (also based on SVM) under the present conditions has been necessary. Finally, specific error conditions in the data acquisition process can automatically be detected now. The recovering process can be automated, thereby avoiding the loss of data in ensuing discharges. (authors)
A Consistent EPIC Visible Channel Calibration Using VIIRS and MODIS as a Reference.

Science.gov (United States)

Haney, C.; Doelling, D. R.; Minnis, P.; Bhatt, R.; Scarino, B. R.; Gopalan, A.

2017-12-01

The Earth Polychromatic Imaging Camera (EPIC) aboard the Deep Space Climate Observatory (DSCOVR) satellite constantly images the sunlit disk of Earth from the Lagrange-1 (L1) point in 10 spectral channels spanning the UV, VIS, and NIR spectrums. Recently, the DSCOVR EPIC team has publicly released version 2 dataset, which has implemented improved navigation, stray-light correction, and flat-fielding of the CCD array. The EPIC 2-year data record must be well-calibrated for consistent cloud, aerosol, trace gas, land use and other retrievals. Because EPIC lacks onboard calibrators, the observations made by EPIC channels must be calibrated vicariously using the coincident measurements from radiometrically stable instruments that have onboard calibration systems. MODIS and VIIRS are best-suited instruments for this task as they contain similar spectral bands that are well-calibrated onboard using solar diffusers and lunar tracking. We have previously calibrated the EPIC version 1 dataset by using EPIC and VIIRS angularly matched radiance pairs over both all-sky ocean and deep convective clouds (DCC). We noted that the EPIC image required navigations adjustments, and that the EPIC stray-light correction provided an offset term closer to zero based on the linear regression of the EPIC and VIIRS ray-matched radiance pairs. We will evaluate the EPIC version 2 navigation and stray-light improvements using the same techniques. In addition, we will monitor the EPIC channel calibration over the two years for any temporal degradation or anomalous behavior. These two calibration methods will be further validated using desert and DCC invariant Earth targets. The radiometric characterization of the selected invariant targets is performed using multiple years of MODIS and VIIRS measurements. Results of these studies will be shown at the conference.
Current status and future potential for advanced volume reduction technologies

International Nuclear Information System (INIS)

Rutland, L.; Naughton, M.D.; Papaiya, N.C.

1984-01-01

With escalating costs for disposal of low-level radioactive waste (LLW) from nuclear power plants, and the possibility of unavailability of disposal space, some nuclear power utilities responded by commiting to implementing advanced volume reduction (VR) systems. This paper presents recent experience to implement advanced volume reduction technologies; their performance and typical operating and capital costs. This experience in the light of current economic conditions may enable us to predict the direction that future advanced VR technology commitments is taking
Bactericidal performance of visible-light responsive titania photocatalyst with silver nanostructures.

Directory of Open Access Journals (Sweden)

Ming-Show Wong

Full Text Available BACKGROUND: Titania dioxide (TiO(2 photocatalyst is primarily induced by ultraviolet light irradiation. Visible-light responsive anion-doped TiO(2 photocatalysts contain higher quantum efficiency under sunlight and can be used safely in indoor settings without exposing to biohazardous ultraviolet light. The antibacterial efficiency, however, remains to be further improved. METHODOLOGY/PRINCIPAL FINDINGS: Using thermal reduction method, here we synthesized silver-nanostructures coated TiO(2 thin films that contain a high visible-light responsive antibacterial property. Among our tested titania substrates including TiO(2, carbon-doped TiO(2 [TiO(2 (C] and nitrogen-doped TiO(2 [TiO(2 (N], TiO(2 (N showed the best performance after silver coating. The synergistic antibacterial effect results approximately 5 log reductions of surviving bacteria of Escherichia coli, Streptococcus pyogenes, Staphylococcus aureus and Acinetobacter baumannii. Scanning electron microscope analysis indicated that crystalline silver formed unique wire-like nanostructures on TiO(2 (N substrates, while formed relatively straight and thicker rod-shaped precipitates on the other two titania materials. CONCLUSION/SIGNIFICANCE: Our results suggested that proper forms of silver on various titania materials could further influence the bactericidal property.
Techniques For Measuring Absorption Coefficients In Crystalline Materials

Science.gov (United States)

Klein, Philipp H.

1981-10-01

Absorption coefficients smaller than 0.001 cm-1 can, with more or less difficulty, be measured by several techniques. With diligence, all methods can be refined to permit measurement of absorption coefficients as small as 0.00001 cm-1. Spectral data are most readily obtained by transmission (spectrophotometric) methods, using multiple internal reflection to increase effective sample length. Emissivity measurements, requiring extreme care in the elimination of detector noise and stray light, nevertheless afford the most accessible spectral data in the 0.0001 to 0.00001 cm-1 range. Single-wavelength informa-tion is most readily obtained with modifications of laser calorimetry. Thermo-couple detection of energy absorbed from a laser beam is convenient, but involves dc amplification techniques and is susceptible to stray-light problems. Photoacoustic detection, using ac methods, tends to diminish errors of these types, but at some expense in experimental complexity. Laser calorimetry has been used for measurements of absorption coefficients as small as 0.000003 cm-1. Both transmission and calorimetric data, taken as functions of intensity, have been used for measurement of nonlinear absorption coefficients.
Data preprocessing methods for robust Fourier ptychographic microscopy

Science.gov (United States)

Zhang, Yan; Pan, An; Lei, Ming; Yao, Baoli

2017-12-01

Fourier ptychographic microscopy (FPM) is a recently developed computational imaging technique that achieves gigapixel images with both high resolution and large field-of-view. In the current FPM experimental setup, the dark-field images with high-angle illuminations are easily overwhelmed by stray lights and background noises due to the low signal-to-noise ratio, thus significantly degrading the achievable resolution of the FPM approach. We provide an overall and systematic data preprocessing scheme to enhance the FPM's performance, which involves sampling analysis, underexposed/overexposed treatments, background noises suppression, and stray lights elimination. It is demonstrated experimentally with both US Air Force (USAF) 1951 resolution target and biological samples that the benefit of the noise removal by these methods far outweighs the defect of the accompanying signal loss, as part of the lost signals can be compensated by the improved consistencies among the captured raw images. In addition, the reported nonparametric scheme could be further cooperated with the existing state-of-the-art algorithms with a great flexibility, facilitating a stronger noise-robust capability of the FPM approach in various applications.
Raman lidar characterization using a reference lamp

Science.gov (United States)

Landulfo, Eduardo; da Costa, Renata F.; Rodrigues, Patricia F.; da Silva Lopes, Fábio J.

2014-10-01

The determination of the amount of water vapor in the atmosphere using lidar is a calibration dependent technique. Different collocated instruments are used for this purpose, like radiossoundings and microwave radiometers. When there are no collocated instruments available, an independente lamp mapping calibration technique can be used. Aiming to stabilish an independ technique for the calibration of the six channels Nd-YAG Raman lidar system located at the Center for Lasers and Applications (CLA), S˜ao Paulo, Brazil, an optical characterization of the system was first performed using a reference tungsten lamp. This characterization is useful to identify any possible distortions in the interference filters, telescope mirror and stray light contamination. In this paper we show three lamp mapping caracterizations (01/16/2014, 01/22/2014, 04/09/2014). The first day is used to demostrate how the tecnique is useful to detect stray light, the second one how it is sensible to the position of the filters and the third one demostrates a well optimized optical system.
Catalytic effect of light illumination on bioleaching of chalcopyrite.

Science.gov (United States)

Zhou, Shuang; Gan, Min; Zhu, Jianyu; Li, Qian; Jie, Shiqi; Yang, Baojun; Liu, Xueduan

2015-04-01

The influence of visible light exposure on chalcopyrite bioleaching was investigated using Acidithiobacillus ferrooxidans. The results indicated, in both shake-flasks and aerated reactors with 8500-lux light, the dissolved Cu was 91.80% and 23.71% higher, respectively, than that in the controls without light. The catalytic effect was found to increase bioleaching to a certain limit, then plateaued as the initial chalcopyrite concentration increased from 2% to 4.5%. Thus a balanced mineral concentration is highly amenable to bioleaching via offering increased available active sites for light adsorption while eschewing mineral aggregation and screening effects. Using semiconducting chalcopyrite, the light facilitated the reduction of Fe(3+) to Fe(2+) as metabolic substrates for A.ferrooxidans, leading to better biomass, lower pH and redox potential, which are conducive to chalcopyrite leaching. The light exposure on iron redox cycling was further confirmed by chemical leaching tests using Fe(3+), which exhibited higher Fe(2+) levels in the light-induced system. Copyright © 2015 Elsevier Ltd. All rights reserved.
A novel bio-degradable polymer stabilized Ag/TiO2 nanocomposites and their catalytic activity on reduction of methylene blue under natural sun light.

Science.gov (United States)

Geetha, D; Kavitha, S; Ramesh, P S

2015-11-01

In the present work we defined a novel method of TiO2 doped silver nanocomposite synthesis and stabilization using bio-degradable polymers viz., chitosan (Cts) and polyethylene glycol (PEG). These polymers are used as reducing agents. The instant formation of AgNPs was analyzed by visual observation and UV-visible spectrophotometer. TiO2 nanoparticles doped at different concentrations viz., 0.03, 0.06 and 0.09mM on PEG/Cts stabilized silver (0.04wt%) were successfully synthesized. This study presents a simple route for the in situ synthesis of both metal and polymer confined within the nanomaterial, producing ternary hybrid inorganic-organic nanomaterials. The results reveal that they have higher photocatalytic efficiencies under natural sun light. The synthesized TiO2 doped Ag nanocomposites (NCs) were characterized by SEM/EDS, TEM, XRD, FTIR and DLS with zeta potential. The stability of Ag/TiO2 nanocomposite is due to the high negative values of zeta potential and capping of constituents present in the biodegradable polymer which is evident from zeta potential and FT-IR studies. The XRD and EDS pattern of synthesized Ag/TiO2 NCs showed their crystalline structure, with face centered cubic geometry oriented in (111) plane. AFM and DLS studies revealed that the diameter of stable Ag/TiO2 NCs was approximately 35nm. Moreover the catalytic activity of synthesize Ag/TiO2 NCs in the reduction of methylene blue was studied by UV-visible spectrophotometer. The synthesized Ag/TiO2 NCs are observed to have a good catalytic activity on the reduction of methylene blue by bio-degradable which is confirmed by the decrease in absorbance maximum value of methylene blue with respect to time using UV-vis spectrophotometer. The significant enhancement in the photocatalytic activity of Ag/TiO2 nanocomposites under sun light irradiation can be ascribed to the effect of noble metal Ag by acting as electron traps in TiO2 band gap. Copyright © 2015. Published by Elsevier Inc.
Hybrid artificial photosynthetic systems comprising semiconductors as light harvesters and biomimetic complexes as molecular cocatalysts.

Science.gov (United States)

Wen, Fuyu; Li, Can

2013-11-19

Solar fuel production through artificial photosynthesis may be a key to generating abundant and clean energy, thus addressing the high energy needs of the world's expanding population. As the crucial components of photosynthesis, the artificial photosynthetic system should be composed of a light harvester (e.g., semiconductor or molecular dye), a reduction cocatalyst (e.g., hydrogenase mimic, noble metal), and an oxidation cocatalyst (e.g., photosystem II mimic for oxygen evolution from water oxidation). Solar fuel production catalyzed by an artificial photosynthetic system starts from the absorption of sunlight by the light harvester, where charge separation takes place, followed by a charge transfer to the reduction and oxidation cocatalysts, where redox reaction processes occur. One of the most challenging problems is to develop an artificial photosynthetic solar fuel production system that is both highly efficient and stable. The assembly of cocatalysts on the semiconductor (light harvester) not only can facilitate the charge separation, but also can lower the activation energy or overpotential for the reactions. An efficient light harvester loaded with suitable reduction and oxidation cocatalysts is the key for high efficiency of artificial photosynthetic systems. In this Account, we describe our strategy of hybrid photocatalysts using semiconductors as light harvesters with biomimetic complexes as molecular cocatalysts to construct efficient and stable artificial photosynthetic systems. We chose semiconductor nanoparticles as light harvesters because of their broad spectral absorption and relatively robust properties compared with a natural photosynthesis system. Using biomimetic complexes as cocatalysts can significantly facilitate charge separation via fast charge transfer from the semiconductor to the molecular cocatalysts and also catalyze the chemical reactions of solar fuel production. The hybrid photocatalysts supply us with a platform to study the
Characterization of Nighttime Light Variability Over the Southeastern United States

Science.gov (United States)

Cole, Tony A.; Molthan, Andrew L.; Schultz, Lori A.

2016-01-01

City lights provide indications of human activity at night. Nighttime satellite imagery offers daily snapshots of this activity. With calibrated, science-quality imagery, long-term monitoring can also be achieved. The degree to which city lights fluctuate, however, is not well known. For the application of detecting power outages, this degree of variability is crucial for assessing reductions to city lights based on historical trends. Eight southeastern U.S. cities are analyzed to understand the relationship between emission variability and several population centers. A preliminary, example case power outage study is also discussed as a transition into future work.
Correlation of light transmittance with asthma attack: fine water particles as a possible inducing factor of asthma.

Science.gov (United States)

Kanaya, Kazuo; Okamoto, Koji; Shimbo, Shinichiro; Ikeda, Masayuki

2011-01-01

It has been postulated that air-borne fine water particles (or mist) can induce asthma attacks in asthmatic children. To date, no attempt has been made to quantify the density of air-borne fine water particles with the aim of relating particle density to the etiology of asthma among children. The aim of this study was to investigate the relation of asthma attack frequency and the particle density evaluated in terms of light transmittance. The density of fine water particles was quantified by measuring reductions in light transmittance at 250, 365 and 580 nm at an outdoor location when the surroundings were in darkness. The measurements were made at distances varying from 1 to 3 m from the light sources and performed every morning and evening for 1 year. Each day was separated into two half-day units [i.e., morning (from midnight to noon) and afternoon (from noon to midnight)]. The number of asthma attacks among 121 enrolled asthmatic children was counted for each unit. A possible correlation between the transmittance reduction and frequency of asthma attacks was assessed. A significant difference was observed in the extent of reduction in light transmittance at 365 nm between the units with asthma attacks and those without attacks. Furthermore, the reduction in the transmittance was more evident when more asthma attacks were recorded among the patients. No difference was detected in the reduction in light transmittance at 250 or 580 nm. These results support the hypothesis that air-borne fine water particles are among the etiological factors that induce asthma attacks in asthmatic children.
Impacts of turbidity on corals: The relative importance of light limitation and suspended sediments

International Nuclear Information System (INIS)

Bessell-Browne, Pia; Negri, Andrew P.; Fisher, Rebecca; Clode, Peta L.; Duckworth, Alan; Jones, Ross

2017-01-01

As part of an investigation of the effects of water quality from dredging/natural resuspension on reefs, the effects of suspended sediment concentrations (SSCs) (0, 30, 100 mg L −1 ) and light (~ 0, 1.1, 8.6 mol photons m −2 d −1 ) were examined alone and in combination, on the corals Acropora millepora, Montipora capricornis and Porites spp. over an extended (28 d) period. No effects were observed at any sediment concentrations when applied alone. All corals in the lowest light treatments lost chlorophyll a and discoloured (bleached) after a week. Coral mortality only occurred in the two lowest light treatments and was higher when simultaneously exposed to elevated SSCs. Compared to water quality data collected during large dredging programs and natural resuspension events (and in the absence of sediment deposition as a cause-effect pathway) these data suggest the light reduction associated with turbidity poses a proportionally greater risk than effects of elevated SSCs alone. - Highlights: • Exposure of corals to low light conditions results in reduced quantum yields followed by bleaching of tissue. • Suspended sediment concentrations, without a reduction in light, have no impact on coral health. • An interaction between elevated suspended sediment concentrations and reduced light result in partial mortality of corals. • Management of dredging should minimise exposure of corals to low light to avoid unnecessary stress and impacts upon health.
High-Voltage LED Light Engine with Integrated Driver

Energy Technology Data Exchange (ETDEWEB)

Soer, Wouter [Lumileds LLC, San Jose, CA (United States)

2016-02-29

LED luminaires have seen dramatic changes in cost breakdown over the past few years. The LED component cost, which until recently was the dominant portion of luminaire cost, has fallen to a level of the same order as the other luminaire components, such as the driver, housing, optics etc. With the current state of the technology, further luminaire performance improvement and cost reduction is realized most effectively by optimization of the whole system, rather than a single component. This project focuses on improving the integration between LEDs and drivers. Lumileds has developed a light engine platform based on low-cost high-power LEDs and driver topologies optimized for integration with these LEDs on a single substrate. The integration of driver and LEDs enables an estimated luminaire cost reduction of about 25% for targeted applications, mostly due to significant reductions in driver and housing cost. The high-power LEDs are based on Lumileds’ patterned sapphire substrate flip-chip (PSS-FC) technology, affording reduced die fabrication and packaging cost compared to existing technology. Two general versions of PSS-FC die were developed in order to create the desired voltage and flux increments for driver integration: (i) small single-junction die (0.5 mm²), optimal for distributed lighting applications, and (ii) larger multi-junction die (2 mm² and 4 mm²) for high-power directional applications. Two driver topologies were developed: a tapped linear driver topology and a single-stage switch-mode topology, taking advantage of the flexible voltage configurations of the new PSS-FC die and the simplification opportunities enabled by integration of LEDs and driver on the same board. A prototype light engine was developed for an outdoor “core module” application based on the multi-junction PSS-FC die and the single-stage switch-mode driver. The light engine meets the project efficacy target of 128 lm/W at a luminous flux

Mechanistic insights into the photocatalytic properties of metal nanocluster/graphene ensembles. Examining the role of visible light in the reduction of 4-nitrophenol.

Science.gov (United States)

Koklioti, Malamatenia A; Skaltsas, Theodosis; Sato, Yuta; Suenaga, Kazu; Stergiou, Anastasios; Tagmatarchis, Nikos

2017-07-13

Metal nanoclusters (M NCs ) based on silver and gold, abbreviated as Ag NCs and Au NCs , respectively, were synthesized and combined with functionalized graphene, abbreviated as f-G, forming novel M NC /f-G ensembles. The preparation of M NCs /f-G was achieved by employing attractive electrostatic interactions developed between negatively charged M NCs , attributed to the presence of carboxylates due to α-lipoic acid employed as a stabilizer, and positively charged f-G, attributed to the presence of ammonium units as addends. The realization of M NC /f-G ensembles was established via titration assays as evidenced by electronic absorption and photoluminescence spectroscopy as well as scanning transmission electron microscopy (STEM) and energy-dispersive X-ray (EDX) spectroscopy analyses. Photoinduced charge-transfer phenomena were inferred within M NCs /f-G, attributed to the suppression of M NC photoluminescence by the presence of f-G. Next, the M NC /f-G ensembles were successfully employed as proficient catalysts for the model reduction of 4-nitrophenol to the corresponding 4-aminophenol as proof for the photoinduced hydrogen production. Particularly, the reduction kinetics decelerated by half when bare M NCs were employed vs. the M NC /f-G ensembles, highlighting the beneficial role of M NCs /f-G in catalysing the process. Furthermore, Au NCs /f-G displayed exceptionally higher catalytic activity both in the dark and under visible light illumination conditions, which is ascribed to three synergistic mechanisms, namely, (a) hydride transfer from Au-H, (b) hydride transfer from photogenerated Au-H species, and (c) hydrogen produced by the photoreduction of water. Finally, recycling and re-employing M NCs /f-G in successive catalytic cycles without loss of activity toward the reduction of 4-nitrophenol was achieved, thereby highlighting their wider applicability.
Light Modulates Leptin and Ghrelin in Sleep-Restricted Adults

Directory of Open Access Journals (Sweden)

Mariana G. Figueiro

2012-01-01

Full Text Available Acute and chronic sleep restrictions cause a reduction in leptin and an increase in ghrelin, both of which are associated with hunger. Given that light/dark patterns are closely tied to sleep/wake patterns, we compared, in a within-subjects study, the impact of morning light exposures (60 lux of 633-nm [red], 532-nm [green], or 475-nm [blue] lights to dim light exposures on leptin and ghrelin concentrations after subjects experienced 5 consecutive days of both an 8-hour (baseline and a 5-hour sleep-restricted schedule. In morning dim light, 5-hour sleep restriction significantly reduced leptin concentrations compared to the baseline, 8-hour sleep/dim-light condition (1,32 = 2.9; =0.007. Compared to the 5-hour sleep/dim-light condition, the red, green, and blue morning light exposures significantly increased leptin concentrations (1,32 = 5.7; <0.0001, 1,32 = 3.6; =0.001, and 1,32 = 3.0; =0.005, resp.. Morning red light and green light exposures significantly decreased ghrelin concentrations (1,32 = 3.3; <0.003 and 1,32 = 2.2; =0.04, resp., but morning blue light exposures did not. This study is the first to demonstrate that morning light can modulate leptin and ghrelin concentrations, which could have an impact on reducing hunger that accompanies sleep deprivation.
Morphological composition of cultivar of Urochloa brizantha under light intensities

Directory of Open Access Journals (Sweden)

Erikelly Aline Ribeiro de Santana

2013-12-01

Full Text Available The implementation of silvopastoral systems (SSP is a management option that gives good results for animal production, but the shading of the trees can alter production, growth behavior and morphological composition of the forage. The aim of the study was to evaluate the morphological composition of Urochloa brizantha cultivars Marandu and Piatã under natural light and artificial shading of 30 and 60%. The experiment was conducted at FMVZ - UNESP, Botucatu. The experimental design was a randomized block in factorial arrangement 3 x 2 (three shading levels: 0, 30 and 60% and two cultivars: Marandu and Piatã with three replications and repeated measures in time (3 cuts. Sample collection occurred when the cultivars reached in 35 cm of height. Significant effects (P<0.05 of cultivar x shade x cut interaction were observed on the dry matter production of leaves and stems (Table 1. The higher production of leaves and stems (P<0.05 occurred for Piatã under natural light in the third cut (3731 and 1920 kg/ha, respectively. The absence of shade favored greater leaf production, 35 and 27% higher than the reductions of 30 and 60% respectively. The increment of stems for Piatã under natural light is related to the increase of inflorescences. The leaf:stem ratio was higher (P< 0.05 for Marandu under natural light (Table 2, with effect from the interaction cultivar x brightness level. A significant effect (P<0.05 cultivar x level of light reduction for light interception parameter was detected (Table 2. For Marandu, light levels were not influenced (P<0.05 light traps (Table 2, being close to the 95% criterion used for pasture management, justified by the collection at the point of balance between forage productivity and nutritional content, and strong relationship with high input grazing. The results indicate that the morphological composition of the cultivars is modified by reducing the light intensity.
Effect of light dispersion of LED curing lights on resin composite polymerization.

Science.gov (United States)

Vandewalle, Kraig S; Roberts, Howard W; Andrus, Jeffrey L; Dunn, William J

2005-01-01

higher DC ratios with the hybrid resin composite. No differences were found among lights with the microfill at 1 mm. At 5 mm, SmartLite iQ, FLASHlite 1001, LEDemetron 1, and UltraLume LED 5 produced significantly higher DC ratios with the hybrid resin composite, whereas LEDemetron 1 and SmartLite iQ produced significantly higher DC ratios with the microfill resin composite. The UltraLume LED 5, Allegro, and Optilux 501 had significant reductions in mean DC ratios at curing distances of 1 and 5 mm with both resin composite types. For dispersion of light, significant differences were found in Top Hat factor and divergence angle (p < .001). SmartLite iQ had overall the highest Top Hat factor and lowest divergence angle of tested lights. A linear regression analysis relating pooled DC with pooled Top Hat factors and divergence angles found a very good correlation (r2 = .86) between dispersion of light over distance and the ability to polymerize resin composite. The latest generation of LED curing lights provides DC ratios similar to or better than the halogen curing light at a curing distance of 5 mm. Dispersion of light plays a significant role in the DC of resin composite. To maximize curing effectiveness, light guides should be maintained in close proximity to the surface of the light-activated restorative material.
Development of a Novel Spectrophotometer for Biochemical Analyzer Based on Volume Holography Transmissive Grating and Linear CCD

International Nuclear Information System (INIS)

Ren Zhong; Liu Guodong; Huang Zhen; Zeng Lvming; Dai Longmin

2011-01-01

The classical surface-embossed plane and concave grating are usually used as the diffraction grating in some spectrophotometers. But the minute cracks are produced on the surface of the gratings' grooves, which leads to generate the stray-light and decrease the efficiency of instrument. Therefore, a novel custom-built spectrophotometer for BCA is developed in this paper. Meanwhile, the volume holography transmissive (VHT) grating is used as the diffraction grating in this spectrophotometer. Additionally, a high resolution CCD and data acquisition (DAQ) card with combined the virtual software platform based on LabVIEW are used to design the spectral acquisition and analysis system. Experimental results show that the spectral range and the diffraction efficiency of the spectrophotometer for BCA are greatly increased. The spectral range of the spectrophotometer for BCA can reach 300-1000 nm, its wavelength resolution can reach 1nm. And, it uses the back-splitting-light technology and multi-channel parallel analysis. Compared with other same types, this spectrophotometer has many advantages, such as, higher efficiency, simpler algorithm, higher accuracy, cheaper cost and fewer stray-light and higher imaging quality, etc. Therefore, this spectrophotometer for BCA based on VHT grating will has the greatly potential values in the fields of the biochemical or medical research.
Prejudice Reduction and Collective Action: A Conflict or Confluence of Interests?

Directory of Open Access Journals (Sweden)

Lucas B. Mazur

2015-12-01

Full Text Available There is a growing body of research findings suggesting that prejudice reduction strategies can have unintended negative consequences, particularly by helping to stabilize systems of inequality. In light of these findings, a handful of scholars have suggested that the field be guided less by the prejudice reduction tradition, so as to focus more on collective action. While agreeing with the recent critiques of prejudice reduction, I argue that in more robustly embracing a collective action approach we should be careful not to abandon the notion of perceptualism that colored original thinking on prejudice reduction, lest we artificially narrow the scope of social psychological research and unintentionally ignore communities that do not fit well within current thinking in the collective action tradition.
Light energy conversion by photocatalytic reaction

Energy Technology Data Exchange (ETDEWEB)

Fujishima, Akira; Yamagata, Sadamu [Univ. of Tokyo (Japan)

1989-01-01

The photocatalytic reaction, to be made to a suspended semiconductor powder system, was explained in summary. By using semiconductor as an electrode for the electrolyzation, etc. and projecting light on it to generate photoelectromotive force, a photocell can be composed. eg., by composing titanium oxide electrode, n-type semiconductor and platinum electrode, and irradiating light on the former electrode to generate electric current, oxygen and hydrogen are produced from the titanium oxide electrode and platinum electrode, respectively, which means the possibility of obtainment of clean energy from water as raw material. Such a wet type photocell, easy to produce, is active also in research. With white titanium oxide powder being suspended in water solution, hydrogen is produced by projecting light into it. Such a semiconductor is called photocatalyst, in which the research has been widely developed, mainly by taking notice of the hydrogen production on reduction side, since 1972. The photocatalysis using colloid and, differently, that doing heteropolyacid are also taken notice of. 24 refs., 6 figs.
Light-Induced Reduction of Cuprous Oxide in an Environmental Transmission Electron Microscope

DEFF Research Database (Denmark)

Cavalca, Filippo Carlo; Laursen, Anders Bo; Wagner, Jakob Birkedal

2013-01-01

Photocatalysts for solar fuel production are subject to intensive investigation as they constitute one viable route for solar energy harvesting. Cuprous oxide (Cu2O) is a working photocatalyst for hydrogen evolution but it photocorrodes upon light illumination in an aqueous environment....... Environmental transmission electron microscopy (ETEM) makes it possible to obtain insight into the local structure, composition and reactivity of catalysts in their working environment, which is of fundamental interest for sustainable energy research and is essential for further material optimization. Herein...
Summary report of the consultants' meeting on improvement of the standard cross sections for light elements

International Nuclear Information System (INIS)

Carlson, A.D.; Muir, D.W.; Pronyaev, V.G.

2001-06-01

This report summarizes the results of the Consultants' Meeting on Improvement of the Standard Cross Sections for Light Elements. The approaches and computer programs used for evaluation of neutron standard cross sections and their uncertainties were presented by the participants. Special attention was paid to the reasons for strong uncertainty reduction observed in the model fits. The meeting participants discussed the plan of the INDC recommended Co-ordinated Research Project (CRP) on 'Improvement of the Standard Cross Sections for Light Elements'. This CRP will address the problem of uncertainty reduction along with other methodological improvements needed in order to produce a new, and internationally accepted, evaluation of neutron standard cross sections for light elements. (author)
Light emitting fabric for photodynamic treatment of actinic keratosis

Science.gov (United States)

Thecua, E.; Vicentini, C.; Vignion, A.-S.; Lecomte, F.; Deleporte, P.; Mortier, L.; Szeimies, R.-M.; Mordon, S.

2017-02-01

The integration of optical fibers into flexible textile structures, by using knitting or weaving processes can allow the development of flexible light sources. The paper aims to present a new technology: Light Emitting Fabrics (LEF), which can be used for example for PDT of Actinic Keratosis in Dermatology. The predetermined macro-bending of optical fibers, led to a homogeneous side emission of light over the entire surface of the fabric. Tests showed that additional curvatures when applying the LEF on non-planar surfaces had no impact on light delivery and proved that LEF can adapt to the human morphology. The ability of the LEF, coupled with a 635nm LASER source, to deliver a homogeneous light to lesions is currently assessed in a clinical trial for the treatment of AK of the scalp by PDT. The low irradiance and progressive activation of the photosensitizer ensure a pain reduction, compared to discomfort levels experienced by patients during a conventional PDT session.
Visibility aspects of road lighting. Contribution to TRB/CIE Symposium on Providing Visibility and Guidance to the Road User, Washington, D.C., July 30 - August 1, 1984.

NARCIS (Netherlands)

Schreuder, D.A.

1984-01-01

The function of road lighting is to enable traffic to function more or less as during the day. The effectiveness of road lighting is expressed in the reduction of nighttime accidents. For important urban roads, the installation of good road lighting will result in a reduction by 30% of nighttime
In the field of energy cost reduction, what is the potential?; En matiere de reduction des depenses d`energie: quel est le gisement?

Energy Technology Data Exchange (ETDEWEB)

Millet, B. [Departement Industrie, CEREN (France)

1996-12-31

Through a segmentation of the fuel and electric power consumptions in the various industrial sectors and energy consumption process types in France in 1990, the energy conservation potential in the French metalworking and mechanical industry is analyzed and its evolution up to 2005 is assessed. It is shown that the reduction potential amounts to 450 kTep or 20 percent of the metalworking and metallic construction industry energy consumption, with an important part for the out-of-process sector (space heating, compressed air production, lighting). In the process sector, important reductions could be realized in thermal treatments and metal heating prior forming
Tocopherols in Sunflower Seedlings under Light and Dark Conditions.

Science.gov (United States)

del Moral, Lidia; Pérez-Vich, Begoña; Velasco, Leonardo

2015-01-01

The objective of this study was to evaluate the dynamics of tocopherols in cotyledons and radicles from sunflower seeds with high and low total tocopherol content, mainly in the α-tocopherol form, and from seeds with increased proportions of β-, γ-, and δ-tocopherol, both under dark and light conditions. Tocopherol content was measured every 24 h from 1 to 12 days after sowing. In all cases, the content of individual tocopherol forms in the cotyledons and radicles was reduced along the sampling period, which was more pronounced under light conditions. The presence of light had a slightly greater effect on α- and γ-tocopherol than on β- and δ-tocopherol. A marked light effect was also observed on total tocopherol content, with light promoting the reduction of tocopherol content in cotyledons and radicles. The study revealed only slight differences in the patterns of tocopherol losses in lines with different tocopherol profiles, both under dark and light conditions, which suggested that the partial replacement of α-tocopherol by other tocopherol forms had no great impact on the protection against oxidative damage in seedlings.
Direct Energy Centre underground parking integrated light control system

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-10-15

LightSavers is a project undertaken by the Toronto Atmospheric Fund to accelerate the use of lighting technologies. As part of the project a pilot test has been carried out in the Direct Energy Center in Toronto. The aim of this report is to present the study and its results. The Direct Energy Center is a large event facility with an large underground parking facility. A lighting energy management system, the energy control system (ECS), capable of adjusting lighting levels based on occupancy was implemented in the centre and data was collected during over one year. Results showed that the ECS permitted a reduction in energy consumption and thus greenhouse gas emissions by 47% and the payback will take less than 6 years. This project demonstrated that the energy control system provides better energy, environmental and economic performance than a traditional automation system.
Reduction of light oil usage as power fluid for jet pumping in deep heavy oil reservoirs

Energy Technology Data Exchange (ETDEWEB)

Chen, S.; Li, H.; Yang, D. [Society of Petroleum Engineers, Canadian Section, Calgary, AB (Canada)]|[Regina Univ., SK (Canada); Zhang, Q. [China Univ. of Petroleum, Dongying, Shandong (China); He, J. [China National Petroleum Corp., Haidan District, Beijing (China). PetroChina Tarim Oilfield Co.

2008-10-15

In deep heavy oil reservoirs, reservoir fluid can flow more easily in the formation as well as around the bottomhole. However, during its path along the production string, viscosity of the reservoir fluid increases dramatically due to heat loss and release of the dissolved gas, resulting in significant pressure drop along the wellbore. Artificial lifting methods need to be adopted to pump the reservoir fluids to the surface. This paper discussed the development of a new technique for reducing the amount of light oil used for jet pumping in deep heavy oil wells. Two approaches were discussed. Approach A uses the light oil as a power fluid first to obtain produced fluid with lower viscosity, and then the produced fluid is reinjected into the well as a power fluid. The process continues until the viscosity of the produced fluid is too high to be utilized. Approach B combines a portion of the produced fluid with the light oil at a reasonable ratio and then the produced fluid-light oil mixture is used as the power fluid for deep heavy oil well production. The viscosity of the blended power fluid continue to increase and eventually reach equilibrium. The paper presented the detailed processes of both approaches in order to indicate how to apply them in field applications. Theoretic models were also developed and presented to determine the key parameters in the field operations. A field case was also presented and a comparison and analysis between the two approaches were discussed. It was concluded from the field applications that, with a certain amount of light oil, the amount of reservoir fluid produced by using the new technique could be 3 times higher than that of the conventional jet pumping method. 17 refs., 3 tabs., 6 figs.
Photochemical eradication of methicillin-resistant Staphylococcus aureus by blue light activation of riboflavin.

Science.gov (United States)

Makdoumi, Karim; Goodrich, Ray; Bäckman, Anders

2017-08-01

To compare elimination of methicillin-resistant Staphylococcus aureus (MRSA) by exposure of blue light alone and with riboflavin. A reference strain of MRSA was cultured and diluted in PBS with and without riboflavin (0.01%). Fifteen microlitre was added on a microscope slide, creating a fluid layer with a thickness of around 400 microns. Both of the bacterial suspensions were exposed to blue light, and the effect between exposure with and without riboflavin was compared. Evaluation involved two different wavelengths (412 and 450 nm) of blue light with a lower (5.4 J/cm 2 ) and higher dose (approximately 28.5 J/cm 2 ). The effect of 412 nm light was also evaluated for a thicker fluid layer (1.17 mm). After exposure, colony-forming units (CFUs) were determined for each solution. All measurements were repeated eight times. The reductions in bacteria were similar for both wavelengths. With riboflavin, a statistically significant elimination was observed for both 412 and 450 nm (p riboflavin than without it. Using the higher dose, CFU reduction was 99% and 98%, respectively, for 412 and 450 nm light. The bactericidal efficacy was high also in the deeper fluid layer (93%, higher dose). Riboflavin enhanced the antibacterial effect on the exposed MRSA strain of blue light for both 412 and 450 nm blue light. This indicates that blue light could be considered for possible implementation in deep corneal infections. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.
Plasma Catalysis for NOx Reduction from Light-Duty Diesel Vehicles

Energy Technology Data Exchange (ETDEWEB)

None

2005-12-15

On behalf of the Department of Energy's Office of FreedomCAR and Vehicle Technologies, we are pleased to introduce the Fiscal Year (FY) 2004 Annual Progress Report for the Advanced Combustion Engine R&D Sub-Program. The mission of the FreedomCAR and Vehicle Technologies Program is to develop more energy efficient and environmentally friendly highway transportation technologies that enable Americans to use less petroleum for their vehicles. The Advanced Combustion Engine R&D Sub-Program supports this mission by removing the critical technical barriers to commercialization of advanced internal combustion engines for light-, medium-, and heavy-duty highway vehicles that meet future Federal and state emissions regulations. The primary objective of the Advanced Combustion Engine R&D Sub-Program is to improve the brake thermal efficiency of internal combustion engines from 30 to 45 percent for light-duty applications by 2010; and 40 to 55 percent for heavy-duty applications by 2012; while meeting cost, durability, and emissions constraints. R&D activities include work on combustion technologies that increase efficiency and minimize in-cylinder formation of emissions, as well as aftertreatment technologies that further reduce exhaust emissions. Work is also being conducted on ways to reduce parasitic and heat transfer losses through the development and application of thermoelectrics and turbochargers that include electricity generating capability, and conversion of mechanically driven engine components to be driven via electric motors. This introduction serves to outline the nature, current progress, and future directions of the Advanced Combustion Engine R&D Sub-Program. The research activities of this Sub-Program are planned in conjunction with the FreedomCAR Partnership and the 21st Century Truck Partnership and are carried out in collaboration with industry, national laboratories, and universities. Because of the importance of clean fuels in achieving low
Smoking reduction and biomarkers in two longitudinal studies

DEFF Research Database (Denmark)

Godtfredsen, Nina; Prescott, Eva; Vestbo, Jørgen

2006-01-01

AIMS: To measure reduction in exposure to smoke in two population-based studies of self-reported smoking reduction not using nicotine replacement. DESIGN: Cross-sectional analyses of biomarkers and smoking. SETTING: Data from two time-points in the Copenhagen City Heart Study (CCHS), 1981....../83 and 1991/94, and the Copenhagen Male Study (CMS) in 1976 and 1985/86, respectively. PARTICIPANTS: There were 3026 adults who were smokers at both time-points in the CCHS and 1319 men smoking at both time-points in the CMS. MEASUREMENTS: Smoking status and tobacco consumption were assessed by self...... a reduction in cigarettes per day of 50% or more without quitting were compared with continuing medium, heavy and light smokers (1-14 g/day) using linear regression. Sex (CCHS only), age, self-reported inhalation of smoke, duration of smoking, type of tobacco and amount smoked were included as covariates...
Development and Performance Evaluation of Light Shelves Using Width-Adjustable Reflectors

Directory of Open Access Journals (Sweden)

Heangwoo Lee

2018-01-01

Full Text Available In recent years, there has been an increase in the consumption of energy for lighting purposes, which has led to an increase in the number of studies being conducted on this subject. Most studies have focused on light shelves, which are daylighting systems used for reducing the lighting energy required for the interiors of buildings. However, the existing light shelves cannot actively deal with external environmental factors, which often lead to an infringement of the right to light during the night when the performance of the light shelf deteriorates. Therefore, in this study, we propose a light shelf with a width-adjustable reflector and verify its validity using a testbed. The reflector of the proposed light shelf system is modularized so that the length can be adjusted in stages. The optimum width of the light shelf is calculated in terms of the energy reduction and uniformity ratio improvement, and the obtained optimum width is varied depending on the season. We find that the width-adjustable reflector can save 20% and 21.6% more lighting energy than light shelves with fixed reflector widths of 0.3 m and 0.6 m, respectively.
Controllable one-pot synthesis of various one-dimensional Bi2S3 nanostructures and their enhanced visible-light-driven photocatalytic reduction of Cr(VI)

International Nuclear Information System (INIS)

Hu, Enlai; Gao, Xuehui; Etogo, Atangana; Xie, Yunlong; Zhong, Yijun; Hu, Yong

2014-01-01

Highlights: • 1D Bi 2 S 3 nanostructures were prepared by a facile ethanol-assisted one-pot reaction. • The size and morphology of the products can be conveniently varied. • The sulfur source plays a crucial role in determining the morphologies of products. • 1D Bi 2 S 3 nanostructures exhibit enhanced photocatalytic reduction of Cr(VI). • Bi 2 S 3 nanowires exhibit the highest photoreduction activity among three samples. - Abstract: One-dimensional (1D) Bi 2 S 3 nanostructures with various morphologies, including nanowires, nanorods, and nanotubes, have been successfully synthesized through a facile ethanol-assisted one-pot reaction. It is found that the size, morphology and structure of the products can be conveniently varied or controlled by simply adjusting the volume ratio of ethanol and water in the reaction system. Further experimental results indicate that sulfur source also plays the other crucial role in determining the product morphology. The synthetic strategy developed in this work is highly efficient in producing 1D Bi 2 S 3 nanostructures with high quality and large quantity. Photocatalysis experiments show the as-prepared 1D Bi 2 S 3 nanostructures possess significantly enhanced photocatalytic reduction of Cr(VI) when exposed to visible light irradiation. Especially, Bi 2 S 3 nanowires exhibit the highest photocatalytic activity and can be used repeatedly after washed with dilute HCl

LED and Halogen Light Transmission through a CAD/CAM Lithium Disilicate Glass-Ceramic.

Science.gov (United States)

Pereira, Carolina Nemesio de Barros; De Magalhães, Cláudia Silami; Daleprane, Bruno; Peixoto, Rogéli Tibúrcio Ribeiro da Cunha; Ferreira, Raquel da Conceição; Cury, Luiz Alberto; Moreira, Allyson Nogueira

2015-01-01

The effect of thickness, shade and translucency of CAD/CAM lithium disilicate glass-ceramic on light transmission of light-emitting diode (LED) and quartz-tungsten-halogen units (QTH) were evaluated. Ceramic IPS e.max CAD shades A1, A2, A3, A3.5, high (HT) and low (LT) translucency were cut (1, 2, 3, 4 and 5 mm). Light sources emission spectra were determined. Light intensity incident and transmitted through each ceramic sample was measured to determine light transmission percentage (TP). Statistical analysis used a linear regression model. There was significant interaction between light source and ceramic translucency (p=0.008) and strong negative correlation (R=-0.845, pceramic thickness and TP. Increasing one unit in thickness led to 3.17 reduction in TP. There was no significant difference in TP (p=0.124) between shades A1 (ß1=0) and A2 (ß1=-0.45) but significant reduction occurred for A3 (ß1=-0.83) and A3.5 (ß1=-2.18). The interaction QTH/HT provided higher TP (ß1=0) than LED/HT (ß1=-2.92), QTH/LT (ß1=-3.75) and LED/LT (ß1=-5.58). Light transmission was more effective using halogen source and high-translucency ceramics, decreased as the ceramic thickness increased and was higher for the lighter shades, A1 and A2. From the regression model (R2=0.85), an equation was obtained to estimate TP value using each variable ß1 found. A maximum TP of 25% for QTH and 20% for LED was found, suggesting that ceramic light attenuation could compromise light cured and dual cure resin cements polymerization.
Implementation of light extraction improvements of GaN-based light-emitting diodes with specific textured sidewalls

Science.gov (United States)

Chen, Chun-Yen; Chen, Wei-Cheng; Chang, Ching-Hong; Lee, Yu-Lin; Liu, Wen-Chau

2018-05-01

Textured-sidewall GaN-based light-emitting diodes (LEDs) with various sidewall angles (15-90°) and convex or concave sidewalls prepared using an inductively-coupled-plasma approach are comprehensively fabricated and studied. The device with 45° sidewalls (Device F) and that with convex sidewalls (Device B) show significant improvements in optical properties. Experiments show that, at an injection current of 350 mA, the light output power, external quantum efficiency, wall-plug efficiency, and luminous flux of Device F (Device B) are greatly improved by 18.3% (18.2%), 18.2% (18.2%), 17.3% (19.8%), and 16.6% (18.4%), respectively, compared to those of a conventional LED with flat sidewalls. In addition, negligible degradation in electrical properties is found. The enhanced optical performance is mainly attributed to increased light extraction in the horizontal direction due to a significant reduction in total internal reflection at the textured sidewalls. Therefore, the reported specific textured-sidewall structures (Devices B and F) are promising for high-power GaN-based LED applications.
Effect of Violet-Blue Light on Streptococcus mutans-Induced Enamel Demineralization

Directory of Open Access Journals (Sweden)

Grace Gomez Felix Gomez

2018-03-01

Full Text Available Background: This in vitro study determined the effectiveness of violet-blue light (405 nm on inhibiting Streptococcus mutans-induced enamel demineralization. Materials and Methods: S. mutans UA159 biofilm was grown on human enamel specimens for 13 h in 5% CO2 at 37 °C with/without 1% sucrose. Wet biofilm was treated twice daily with violet-blue light for five minutes over five days. A six-hour reincubation was included daily between treatments excluding the final day. Biofilms were harvested and colony forming units (CFU were quantitated. Lesion depth (L and mineral loss (∆Z were quantified using transverse microradiography (TMR. Quantitative light-induced fluorescence Biluminator (QLF-D was used to determine mean fluorescence loss. Data were analyzed using one-way analysis of variance (ANOVA to compare differences in means. Results: The results demonstrated a significant reduction in CFUs between treated and non-treated groups grown with/without 1% sucrose. ∆Z was significantly reduced for specimens exposed to biofilms grown without sucrose with violet-blue light. There was only a trend on reduction of ∆Z with sucrose and with L on both groups. There were no differences in fluorescence-derived parameters between the groups. Conclusions: Within the limitations of the study, the results indicate that violet-blue light can serve as an adjunct prophylactic treatment for reducing S. mutans biofilm formation and enamel mineral loss.
Light extraction improvement of InGaN light-emitting diodes with large-area highly ordered ITO nanobowls photonic crystal via self-assembled nanosphere lithography

Directory of Open Access Journals (Sweden)

Kui Wu

2013-09-01

Full Text Available The InGaN multiple quantum well light-emitting diodes (LEDs with different sizes of indium-tin-oxide (ITO nanobowl photonic crystal (PhC structure has been fabricated using self-assembled monolayer nanosphere lithography. The light output power (LOP of PhC LEDs (at 350 mA has been enhanced by 63.5% and the emission divergence exhibits a 28.8° reduction compared to conventional LEDs without PhC structure. Current-Voltage curves have shown that these PhC structures on ITO layer will not degrade the LED electrical properties. The finite-difference time-domain simulation (FDTD has also been performed for light extraction and emission characteristics, which is consistent with the experimental results.
WOW: light print, light propel, light point

DEFF Research Database (Denmark)

Glückstad, Jesper; Bañas, Andrew Rafael; Aabo, Thomas

2012-01-01

anywhere in a sample at any orientation using real-time 3D optical micromanipulation with six degrees of freedom. One of the key aspects of our demonstrated WOWs is the change in direction of in-coupled light and the marked increase in numerical aperture of the out-coupled light. Hence, each light...... propelled WOW can tap from a relatively broad incident beam and generate a much more tightly confined light at its tip. The presentation contains both numerical simulations related to the propagation of light through a WOW and preliminary experimental demonstrations on our BioPhotonics Workstation...
Searching for transits in the Wide Field Camera Transit Survey with difference-imaging light curves

NARCIS (Netherlands)

Zendejas, Dominguez J.; Koppenhoefer, J.; Saglia, R.; Birkby, J.L.; Hodgkin, S.; Kovács, G.; Pinfield, D.; Sipocz, B.; Barrado, D.; Bender, R.; Burgo, del C.; Cappetta, M.; Martín, E.; Nefs, B.; Riffeser, A.; Steele, P.

2013-01-01

The Wide Field Camera Transit Survey is a pioneer program aiming at for searching extra-solar planets in the near-infrared. The images from the survey are processed by a data reduction pipeline, which uses aperture photometry to construct the light curves. We produce an alternative set of light
Riboflavin-ultraviolet light pathogen reduction treatment does not impact the immunogenicity of murine red blood cells.

Science.gov (United States)

Tormey, Christopher A; Santhanakrishnan, Manjula; Smith, Nicole H; Liu, Jingchun; Marschner, Susanne; Goodrich, Raymond P; Hendrickson, Jeanne E

2016-04-01

Ultraviolet (UV) illumination/pathogen reduction effectively inactivates white blood cells (WBCs) in whole blood. Given that cotransfused WBCs may impact recipient immune responses, we hypothesized that pathogen reduction of whole blood may alter responses to RBC antigens. Transgenic mice expressing a model (HOD) antigen, authentic human (hGPA or KEL) antigens, or natural fluorescence (uGFP) on their RBCs were utilized as blood donors. Recipients were transfused with fresh whole blood to which riboflavin had been added or fresh whole blood treated by UV illumination/pathogen reduction treatment after the addition of riboflavin. Posttransfusion RBC recovery, survival, and alloimmunization were measured by flow cytometry. UV illumination/pathogen reduction treatment did not alter RBC antigen expression, and recipients of treated syngeneic RBCs had persistently negative direct antiglobulin tests. Greater than 75% of treated and untreated syngeneic RBCs were recovered 24 hours posttransfusion in all experiments, although alterations in the long-term posttransfusion survival of treated RBCs were observed. Treated and untreated KEL RBCs induced similar recipient alloimmune responses, with all recipients making anti-KEL glycoprotein immunoglobulins (p > 0.05). Alloimmune responses to treated HOD or hGPA RBCs were no different from untreated RBCs (p > 0.05). Pathogen inactivation treatment of fresh whole murine blood with riboflavin and UV illumination does not impact the rate or magnitude of RBC alloimmunization to three distinct RBC antigens. Further, UV illumination/pathogen reduction appears safe from an immunohematologic standpoint, with no immunogenic neoantigens detected on treated murine RBCs. Future studies with fresh and stored human RBCs are warranted to confirm these findings. © 2015 AABB.
Bright Light for Weight Loss: Results of a Controlled Crossover Trial

Directory of Open Access Journals (Sweden)

Konstantin V. Danilenko

2013-02-01

Full Text Available Objective: To investigate whether bright light treatment can reduce body mass in overweight subjects irrespective of their seasonal (= light dependence. Methods: A crossover, placebo-controlled, randomized clinical trial was performed between November and April in Novosibirsk, Russia (55° N. The trial comprised a 3-week in-home session of morning bright light treatment using a device of light-emitting diodes and a 3-week placebo session by means of a deactivated ion generator, separated by an off-protocol period of at least 23 days. The number of placebo and light sessions was matched with respect to season. Data were obtained from 34 overweight women, aged 20-54 years, 10 were seasonal-dependent according to the Seasonal Pattern Assessment Questionnaire. Weekly measures included body weight, percentage body fat by bioimpedancemetry, and subjective scores (appetite, mood, energy levels. Results: Motivation and expectation towards weight loss were similar for the two intervention sessions. With light, compared to the placebo session, weight did not reduce significantly, but percentage fat, fat mass, and appetite were significantly lower (average fat reduction 0.35 kg. The latter two results remained significant after excluding seasonal-dependent subjects from the analysis. Irrespective of the type of intervention, seasonal-dependent subjects had greater weight and fat mass changes during treatment (decline p 0.036 or between sessions (regain p 0.003. Photoperiod (p = 0.0041, air temperature to a lesser extent (p = 0.012, but not sunshine (p = 0.29 was associated with the weight change (greater weight reduction if the second session was in spring. Conclusion: Morning bright light treatment reduces body fat and appetite in overweight women and may be included in weight control programs.
Counter of Energy Conservation and Emission Reduction for the Public in China

Energy Technology Data Exchange (ETDEWEB)

Wujun Wen; Xiaowen Liu; Geng Xu (Research Center for Sustainable Development of Shandong Province, Shandong Normal Univ., Jinan Shandong 250014 (China)). e-mail: wenwj@sdnu.edu.cn

2009-05-15

The Ministry of Science and Technology of China organized experts to develop the Internet-based software Counter of Energy Conservation and Emission Reduction to directly measure energy conservation and emission reduction potentials in people's daily lives. Research and testing of the software have been completed, and the software is available to the public on the Internet. The Counter of Energy Conservation and Emission Reduction software is being promoted with the aim of stimulating the public's enthusiasm for energy conservation and emission reduction. The software is of great significance in energy conservation and emission reduction education oriented to elementary and middle school students and community residents, thus changing the lagged public participation of Chinese citizens in energy conservation and emission reduction. The counter can calculate people's energy conservation and emission reduction potential in six aspects of daily life. The user can know his or her value of energy conservation and emission reduction in each aspect by clicking the options in keeping with his or her true daily routines. The user can also know the amounts of energy conservation and emission reduction as well as the potential energy conservation and emission reduction of the whole nation by clicking the Effect Calculation Button. Family life areas mainly include the methods and habits of water use, the use of energy conservation cookers, methods of saving paper, the use of environmental protection products, the habit of home appliance use, and the methods of washing clothing, especially the use of the washing machine with the function of energy conservation. Housing includes the building materials, the heating and cooling systems, the temperature control measures, and the lighting, etc. Heating and cooling times for the house by air conditioner should be reduced. Architects can do a great deal by using energy-efficient building materials and designing houses
Light energy dissipation under water stress conditions

International Nuclear Information System (INIS)

Stuhlfauth, T.; Scheuermann, R.; Fock, H.P.

1990-01-01

Using 14 CO 2 gas exchange and metabolite analyses, stomatal as well as total internal CO 2 uptake and evolution were estimated. Pulse modulated fluorescence was measured during induction and steady state of photosynthesis. Leaf water potential of Digitalis lanata EHRH. plants decreased to -2.5 megapascals after withholding irrigation. By osmotic adjustment, leaves remained turgid and fully exposed to irradiance even at severe water stress. Due to the stress-induced reduction of stomatal conductance, the stomatal CO 2 exchange was drastically reduced, whereas the total CO 2 uptake and evolution were less affected. Stomatal closure induced an increase in the reassimilation of internally evolved CO 2 . This CO 2 -recycling consumes a significant amount of light energy in the form of ATP and reducing equivalents. As a consequence, the metabolic demand for light energy is only reduced by about 40%, whereas net photosynthesis is diminished by about 70% under severe stress conditions. By CO 2 recycling, carbon flux, enzymatic substrate turnover and consumption of light energy were maintained at high levels, which enabled the plant to recover rapidly after rewatering. In stressed D. lanata plants a variable fluorescence quenching mechanism, termed coefficient of actinic light quenching, was observed. Besides water conservation, light energy dissipation is essential and involves regulated metabolic variations
Low scatter edge blackening compounds for refractive optical elements

International Nuclear Information System (INIS)

Lewis, I.T.; Telkamp, A.R.; Ledebuhr, A.G.

1989-01-01

This paper reports on low scatter edge blackening compounds for refractive optical elements. Perkin-Elmer's Applied Optics Operation recently delivered several prototype wide-field-of-view (WFOV), F/2.8, 250 mm efl, near diffraction limited, concentric lenses toLawrence Livermore National Laboratory (LLNL). In these lenses, special attention was paid to reducing stray light to allow viewing of very dim objects. Because of the very large FOV, the use of a long baffle to eliminate direct illumination of lens edges was not practical. With the existing relatively short baffle design, one-bounce stray light paths off the element edges are possible. The scattering off the inside edges thus had to be kept to an absolute minimum. While common means for blackening the edges of optical elements are easy to apply and quite cost effective for normal lens assemblies, their blackening effect is limited by the Fresnel reflection due to the index of refraction mismatch at the glass boundary. At high angles of incidence, total internal reflection (TIR) might occur ruining the effect of the blackening process. An index-match absorbing medium applied to the edges of such elements is the most effective approach for reducing the amount of undesired light reflection or scattered off these edges. The presence of such a medium provides an extended path outside the glass boundary in which an absorptive non-scattering dye can be used to eliminate light that might otherwise have propagated to the focal plane
Role of quantum correlations in light-matter quantum heat engines

Science.gov (United States)

Barrios, G. Alvarado; Albarrán-Arriagada, F.; Cárdenas-López, F. A.; Romero, G.; Retamal, J. C.

2017-11-01

We study a quantum Otto engine embedding a working substance composed of a two-level system interacting with a harmonic mode. The physical properties of the substance are described by a generalized quantum Rabi model arising in superconducting circuit realizations. We show that light-matter quantum correlation reduction during the hot bath stage and adiabatic stages act as an indicator for enhanced work extraction and efficiency, respectively. Also, we demonstrate that the anharmonic spectrum of the working substance has a direct impact on the transition from heat engine into refrigerator as the light-matter coupling is increased. These results shed light on the search for optimal conditions in the performance of quantum heat engines.
Real-time evaluation of two light delivery systems for photodynamic disinfection of Candida albicans biofilm in curved root canals.

Science.gov (United States)

Sabino, C P; Garcez, A S; Núñez, S C; Ribeiro, M S; Hamblin, M R

2015-08-01

Antimicrobial photodynamic therapy (APDT) combined with endodontic treatment has been recognized as an alternative approach to complement conventional root canal disinfection methods on bacterial biofilms. We developed an in vitro model of bioluminescent Candida albicans biofilm inside curved dental root canals and investigated the microbial reduction produced when different light delivery methods are employed. Each light delivery method was evaluated in respect to the light distribution provided inside curved root canals. After conventional endodontic preparation, teeth were sterilized before canals were contaminated by a bioluminescent strain of C. albicans (CEC789). Methylene blue (90 μM) was introduced into the canals and then irradiated (λ = 660 nm, P = 100 mW, beam diameter = 2 mm) with laser tip either in contact with pulp chamber or within the canal using an optical diffuser fiber. Light distribution was evaluated by CCD camera, and microbial reduction was monitored through bioluminescence imaging. Our findings demonstrated that the bioluminescent C. albicans biofilm model had good reproducibility and uniformity. Light distribution in dental tissue was markedly dependent on the light delivery system, and this strategy was directly related to microbial destruction. Both light delivery systems performed significant fungal inactivation. However, when irradiation was performed with optical diffuser fiber, microbial burden reduction was nearly 100 times more effective. Bioluminescence is an interesting real-time analysis to endodontic C. albicans biofilm inactivation. APDT showed to be an effective way to inactivate C. albicans biofilms. Diffuser fibers provided optimized light distribution inside curved root canals and significantly increased APDT efficiency.
[Light pollution increases morbidity and mortality rate from different causes in male rats].

Science.gov (United States)

Bukalev, A V; Vinogradova, I A; Zabezhinskiĭ, M A; Semenchenko, A V; Anisimov, V N

2012-01-01

The influence of different light regimes (constant light--LL; constant darkness--DD; standard light regime--LD, 12 hours light 12 hours darkness; natural lightening of the North-West of Russia--NL) on the dynamics of life's morbidity rate, spontaneous tumorigenesis and frequency of some kinds of non-tumor pathology revealed at the post-mortem examination of male rats was studied. It was found out that the maintenance of animals at LL and NL conditions led to the increase of the number of infectious diseases, substantially faster development of spontaneous tumors and the increase of non-tumor diseases in comparison with the animals kept at LD (standard light) regime. Light deprivation (DD) led to substantial reduction of development of new growth, of non-tumor and infectious diseases in comparison with the similar parameters in standard light regime.
Low light intensity and nitrogen starvation modulate the chlorophyll content of Scenedesmus dimorphus.

Science.gov (United States)

Ferreira, V S; Pinto, R F; Sant'Anna, C

2016-03-01

Chlorophyll is a photosynthetic pigment found in plants and algal organisms and is a bioproduct with human health benefits and a great potential for use in the food industry. The chlorophyll content in microalgae strains varies in response to environmental factors. In this work, we assessed the effect of nitrogen depletion and low light intensity on the chlorophyll content of the Scenedesmus dimorphus microalga. The growth of S. dimorphus under low light intensity led to a reduction in cell growth and volume as well as increased cellular chlorophyll content. Nitrogen starvation led to a reduction in cell growth and the chlorophyll content, changes in the yield and productivity of chlorophylls a and b. Transmission electron microscopy was used to investigate the ultrastructural changes in the S. dimorphus exposed to nitrogen and light deficiency. In contrast to nitrogen depletion, low light availability was an effective mean for increasing the total chlorophyll content of green microalga S. dimorphus. The findings acquired in this work are of great biotechnological importance to extend knowledge of choosing the right culture condition to stimulate the effectiveness of microalgae strains for chlorophyll production purposes. © 2015 The Society for Applied Microbiology.
Bacterial and protozoal agents of feline vector-borne diseases in domestic and stray cats from southern Portugal

Science.gov (United States)

2014-01-01

Background Feline vector-borne diseases (FVBD) have emerged in recent years, showing a wider geographic distribution and increased global prevalence. In addition to their veterinary importance, domestic cats play a central role in the transmission cycles of some FVBD agents by acting as reservoirs and sentinels, a circumstance that requires a One Health approach. The aim of the present work was to molecularly detect feline vector-borne bacteria and protozoa with veterinary and zoonotic importance, and to assess associated risk factors in cats from southern Portugal. Methods Six hundred and forty-nine cats (320 domestic and 329 stray), from veterinary medical centres and animal shelters in southern Portugal, were studied. Anaplasma spp./Ehrlichia spp., Babesia spp., Bartonella spp., Borrelia burgdorferi sensu lato, Hepatozoon spp. and Leishmania spp. infections were evaluated by polymerase chain reaction (PCR) in blood samples. Results One hundred and ninety-four (29.9%) cats were PCR-positive to at least one of the tested genera or complex of FVBD agents. Sixty-four (9.9%) cats were positive to Leishmania spp., 56 (8.6%) to Hepatozoon spp., 43 (6.6%) to Babesia spp., 35 (5.4%) to Anaplasma spp./Ehrlichia spp., 19 (2.9%) to Bartonella spp. and 14 (2.2%) to B. burgdorferi s.l. Thirty-three (5.1%) cats were positive to two (n = 29) or three (n = 4) genera/complex. Babesia vogeli, Bartonella clarridgeiae, Bartonella henselae, Ehrlichia canis, Hepatozoon felis and Leishmania infantum were identified by DNA sequencing. Conclusions The occurrence of FVBD agents in southern Portugal, some of them with zoonotic character, emphasizes the need to alert the veterinary community, owners and public health authorities for the risk of infection. Control measures should be implemented to prevent the infection of cats, other vertebrate hosts and people. PMID:24655431
Cognitive effects of head-movements in stray fields generated by a 7 Tesla whole-body MRI magnet.

Science.gov (United States)

de Vocht, F; Stevens, T; Glover, P; Sunderland, A; Gowland, P; Kromhout, H

2007-05-01

The study investigates the impact of exposure to the stray magnetic field of a whole-body 7 T MRI scanner on neurobehavioral performance and cognition. Twenty seven volunteers completed four sessions, which exposed them to approximately 1600 mT (twice), 800 mT and negligible static field exposure. The order of exposure was assigned at random and was masked by placing volunteers in a tent to hide their position relative to the magnet bore. Volunteers completed a test battery assessing auditory working memory, eye-hand co-ordination, and visual perception. During three sessions the volunteers were instructed to complete a series of standardized head movements to generate additional time-varying fields ( approximately 300 and approximately 150 mT.s(-1) r.m.s.). In one session, volunteers were instructed to keep their heads as stable as possible. Performance on a visual tracking task was negatively influenced (P<.01) by 1.3% per 100 mT exposure. Furthermore, there was a trend for performance on two cognitive-motor tests to be decreased (P<.10). No effects were observed on working memory. Taken together with results of earlier studies, these results suggest that there are effects on visual perception and hand-eye co-ordination, but these are weak and variable between studies. The magnitude of these effects may depend on the magnitude of time-varying fields and not so much on the static field. While this study did not include exposure above 1.6 T, it suggests that use of strong magnetic fields is not a significant confounder in fMRI studies of cognitive function. Future work should further assess whether ultra-high field may impair performance of employees working in the vicinity of these magnets. (c) 2007 Wiley-Liss, Inc.
Selective disulfide reduction for labeling and enhancement of Fab antibody fragments

International Nuclear Information System (INIS)

Kirley, Terence L.; Greis, Kenneth D.; Norman, Andrew B.

2016-01-01

Many methods have been developed for chemical labeling and enhancement of the properties of antibodies and their common fragments, including the Fab and F(ab’) 2 fragments. Somewhat selective reduction of some antibody disulfide bonds has been previously achieved, yielding antibodies and antibody fragments that can be labeled at defined sites, enhancing their utility and properties. Selective reduction of the two hinge disulfide bonds present in F(ab’) 2 fragments using mild reduction has been useful. However, such reduction is often not quantitative and results in the reduction of multiple disulfide bonds, and therefore subsequent multiple labeling or conjugation sites are neither homogenous nor stoichiometric. Here, a simple and efficient selective reduction of the single disulfide bond linking the partial heavy chain and the intact light chain which compose the Fab fragment is accomplished utilizing tris(2-carboxyethyl)phosphine (TCEP) immobilized on agarose beads. The resultant reduced cysteine residues were labeled with several cysteine-selective fluorescent reagents, as well as by cysteine-directed PEGylation. These two cysteine residues can also be re-ligated by means of a bifunctional cysteine cross-linking agent, dibromobimane, thereby both restoring a covalent linkage between the heavy and light chains at this site, far removed from the antigen binding site, and also introducing a fluorescent probe. There are many other research and clinical uses for these selectively partially reduced Fab fragments, including biotinylation, toxin and drug conjugation, and incorporation of radioisotopes, and this technique enables simple generation of very useful Fab fragment derivatives with many potential applications. - Highlights: • TCEP agarose is effective for selective reduction of a single Fab disulfide bond. • This disulfide is solvent accessible and distant from the antigen binding site. • A variety of buffers of varying pHs can be used, simplifying
Carbon-doped SnS2 nanostructure as a high-efficiency solar fuel catalyst under visible light.

Science.gov (United States)

Shown, Indrajit; Samireddi, Satyanarayana; Chang, Yu-Chung; Putikam, Raghunath; Chang, Po-Han; Sabbah, Amr; Fu, Fang-Yu; Chen, Wei-Fu; Wu, Chih-I; Yu, Tsyr-Yan; Chung, Po-Wen; Lin, M C; Chen, Li-Chyong; Chen, Kuei-Hsien

2018-01-12

Photocatalytic formation of hydrocarbons using solar energy via artificial photosynthesis is a highly desirable renewable-energy source for replacing conventional fossil fuels. Using an L-cysteine-based hydrothermal process, here we synthesize a carbon-doped SnS 2 (SnS 2 -C) metal dichalcogenide nanostructure, which exhibits a highly active and selective photocatalytic conversion of CO 2 to hydrocarbons under visible-light. The interstitial carbon doping induced microstrain in the SnS 2 lattice, resulting in different photophysical properties as compared with undoped SnS 2 . This SnS 2 -C photocatalyst significantly enhances the CO 2 reduction activity under visible light, attaining a photochemical quantum efficiency of above 0.7%. The SnS 2 -C photocatalyst represents an important contribution towards high quantum efficiency artificial photosynthesis based on gas phase photocatalytic CO 2 reduction under visible light, where the in situ carbon-doped SnS 2 nanostructure improves the stability and the light harvesting and charge separation efficiency, and significantly enhances the photocatalytic activity.
Visible light photoreduction of CO.sub.2 using heterostructured catalysts

Science.gov (United States)

Matranga, Christopher; Thompson, Robert L; Wang, Congjun

2015-03-24

The method provides for use of sensitized photocatalyst for the photocatalytic reduction of CO.sub.2 under visible light illumination. The photosensitized catalyst is comprised of a wide band gap semiconductor material, a transition metal co-catalyst, and a semiconductor sensitizer. The semiconductor sensitizer is photoexcited by visible light and forms a Type II band alignment with the wide band gap semiconductor material. The wide band gap semiconductor material and the semiconductor sensitizer may be a plurality of particles, and the particle diameters may be selected to accomplish desired band widths and optimize charge injection under visible light illumination by utilizing quantum size effects. In a particular embodiment, CO.sub.2 is reduced under visible light illumination using a CdSe/Pt/TiO2 sensitized photocatalyst with H.sub.2O as a hydrogen source.

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