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Sample records for stray fields emanating

  1. Correcting GOES-R Magnetometer Data for Stray Fields

    Science.gov (United States)

    Carter, Delano; Freesland, Douglas; Tadikonda, Sivakumara K.; Kronenwetter, Jeffrey; Todirita, Monica; Dahya, Melissa; Chu, Donald

    2016-05-01

    Time-varying spacecraft magnetic fields, i.e. stray fields, are a problem for magnetometer systems. While constant fields can be removed by calibration, stray fields are difficult to distinguish from ambient field variations. Putting two magnetometers on a long boom and solving for both the ambient and stray fields can help, but this gradiometer solution is more sensitive to noise than a single magnetometer. As shown here for the R-series Geostationary Operational Environmental Satellites (GOES-R), unless the stray fields are larger than the noise, simply averaging the two magnetometer readings gives a more accurate solution. If averaging is used, it may be worthwhile to estimate and remove stray fields explicitly. Models and estimation algorithms to do so are provided for solar array, arcjet and reaction wheel fields.

  2. Stray light field dependence for large astronomical space telescopes

    Science.gov (United States)

    Lightsey, Paul A.; Bowers, Charles W.

    2017-09-01

    aspect ratio of the tubular baffle length to PM diameter. Additional analysis has been done to examine the stray light implications for the fields near the image of a bright source. This near field stray light is shown to be dependent on the Bidirectional Reflectance Distribution Function (BRDF) characteristics of the mirrors in the optical train. The near field stray light contribution is dominated by those mirrors closer to the focal plane compared to the contributions from the PM and SM. Hence the near field stray light is independent of the exterior telescope baffle geometry. Contributions from self-emission from the telescope have been compared to natural background for telescopes operating at infrared wavelengths.

  3. Calculation and optimization of stray fields of septum dipole magnets

    CERN Document Server

    Holmes, Andrew J T

    1976-01-01

    A theoretical treatment is described of the external stray field of C- shaped septum magnets, such as those designed for the beam extraction systems of the 400 GeV CERN Super Proton Synchrotron. A special conformal transformation of the magnetic plane yields analytic expressions for the four components of the stray field: the septum- shape field (due to the form of the septum conductor), the edge-effect field (due to the mechanical clearance between septum and yoke), the cooling-duct field (due to the presence of these ducts in the septum), and the magnetomotance field (caused by the ampere-turn losses in the yoke). These expressions can be computed by numerical iteration. The septum-shape field turns out to be opposite in sign to the other three, making possible a criterion which creates a minimal stray field for a given magnetic induction. Plots of calculated and measured stray fields are presented for four prototype septum magnets whose total induction is between 0.38 and 1.41 T. (3 refs).

  4. Magnetic stray fields of periodically arranged Co-Crmicro strips

    NARCIS (Netherlands)

    te Lintelo, J.G.T.; te Lintelo, J.G.T.

    Research was carried out on magnetic stray fields of Co-Cr micro strips. This investigation was motivated by the search for increasing bit density and miniaturisation in magnetic data storage and magnetic sensor devices. In these devices the magnetisation is patterned, i.e. by writing bits or

  5. Magnetic stray fields of periodically arranged Co-Crmicro strips

    NARCIS (Netherlands)

    te Lintelo, J.G.T.; te Lintelo, J.G.T.

    1993-01-01

    Research was carried out on magnetic stray fields of Co-Cr micro strips. This investigation was motivated by the search for increasing bit density and miniaturisation in magnetic data storage and magnetic sensor devices. In these devices the magnetisation is patterned, i.e. by writing bits or

  6. Characterisation of MFM tip stray fields using Lorentz electron tomography

    CERN Document Server

    Scott, J

    2001-01-01

    considered, as is a possible improved design of DPC detector. distribution a tomographic method must be used. The collection and calibration of the tomographic data series is discussed, including the special sample mounting methods required. To understand the principles behind MFM, the theory behind atomic force microscopy (AFM) is discussed at length in Chapter 3. The extension of AFM to MFM is covered, and the simple point charge analysis of the MFM imaging process is reviewed. A more sophisticated analysis is then presented, based on the knowledge of the MFM point- response function. It is demonstrated that in some cases, the magnetic charge distribution of a samples can be extracted provided that the response function of the MFM tip (related directly to the stray field distribution from the tip) is known. Finally, some specialised MFM techniques are briefly reviewed. In Chapter 4, prototype tips (produced at Sheffield University) coated with a low-coercivity amorphous ferromagnetic alloy (METGLAS 2605SC) ...

  7. 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

  8. Effect of a Transverse Magnetic Field on Stray Grain Formation of Ni-Based Single Crystal Superalloy During Directional Solidification

    Science.gov (United States)

    Xuan, Weidong; Liu, Huan; Lan, Jian; Li, Chuanjun; Zhong, Yunbo; Li, Xi; Cao, Guanghui; Ren, Zhongming

    2016-12-01

    The effect of a transverse magnetic field on stray grain formation during directional solidification of superalloy was investigated. Experimental results indicated that the transverse magnetic field effectively suppressed the stray grain formation on the side the primary dendrite diverges from the mold wall. Moreover, the quenched experimental results indicated that the solid/liquid interface shape was obviously changed in a transverse magnetic field. The effect of a transverse magnetic field on stray grain formation was discussed.

  9. Numerical Methods for the Stray-Field Calculation: A Comparison of recently developed Algorithms

    CERN Document Server

    Abert, Claas; Selke, Gunnar; Drews, André; Schrefl, Thomas

    2012-01-01

    Different numerical approaches for the stray-field calculation in the context of micromagnetic simulations are investigated. We compare finite difference based fast Fourier transform methods, tensor grid methods and the finite-element method with shell transformation in terms of computational complexity, storage requirements and accuracy tested on several benchmark problems. These methods can be subdivided into integral methods (fast Fourier transform methods, tensor-grid method) which solve the stray field directly and in differential equation methods (finite-element method), which compute the stray field as the solution of a partial differential equation. It turns out that for cuboid structures the integral methods, which work on cuboid grids (fast Fourier transform methods and tensor grid methods) outperform the finite-element method in terms of the ratio of computational effort to accuracy. Among these three methods the tensor grid method is the fastest. However, the use of the tensor grid method in the c...

  10. Stray-field-induced Faraday contributions in wide-field Kerr microscopy and -magnetometry

    Energy Technology Data Exchange (ETDEWEB)

    Markó, D.; Soldatov, I. [Leibniz Institute for Solid State and Materials Research (IFW) Dresden, Institute for Metallic Materials, PO 270116, D-01171 Dresden (Germany); Dresden University of Technology, Institute for Materials Science, D-01062 Dresden (Germany); Tekielak, M. [Institute of Experimental Physics, University of Bialystok, Lipowa 41, Bialystok 15-424 Poland (Poland); Schäfer, R., E-mail: r.schaefer@ifw-dresden.de [Leibniz Institute for Solid State and Materials Research (IFW) Dresden, Institute for Metallic Materials, PO 270116, D-01171 Dresden (Germany); Dresden University of Technology, Institute for Materials Science, D-01062 Dresden (Germany)

    2015-12-15

    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.

  11. 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.

  12. Effect of stray electric fields on cooling of center of mass motion of levitated graphite flakes

    Science.gov (United States)

    Nagornykh, Pavel; Coppock, Joyce; Kane, Bruce

    2015-03-01

    Levitation of charged multilayer graphene flakes in a quadrupole ion trap provides a unique way to study graphene in isolated conditions. Cooling of a flake in such a setup is necessary for high vacuum measurements of the flake and is achieved by using a parametric feedback scheme. We present data showing the strong dependence of the cooling of the flake's center of mass motion on the stray electric fields. We achieve this by using auxiliary electrodes to shift the position of the trap center in space. Once the point of minimum interaction between the stray fields and the particle is found (leading to cooling of the flake motion to temperatures below 20K at pressure of 10-7 Torr), we can estimate charge and mass of the flake by observing quantized discharge of the particle and measure transient dynamics of the center of mass motion by turning the cooling off and on. As an additional benefit, the behavior of the flake away from the optimum trap position can be used to quantify stray fields' effect on the particle motion by measuring its spinning orientation and frequency dependence on offset from the optimum position.

  13. 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.

  14. 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.

  15. 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%.

  16. Effects of magnetic stray fields from a 7 Tesla MRI scanner on neurocognition: a double-blind randomised crossover study

    NARCIS (Netherlands)

    van Nierop, L.E.; Slottje, P.; van Zandvoort, M.J.; de Vocht, F.; Kromhout, H.

    2012-01-01

    OBJECTIVE This study characterises neurocognitive domains that are affected by movement-induced time-varying magnetic fields (TVMF) within a static magnetic stray field (SMF) of a 7 Tesla (T) MRI scanner. METHODS Using a double-blind randomised crossover design, 31 healthy volunteers were tested in

  17. Energy harvesting from stray power-frequency magnetic field employing a piezoelectric unimorph based heterostructure

    Science.gov (United States)

    He, Wei; Lu, Yueran; Zhang, Jitao; Qu, Chiwen; Che, Gaofeng; Peng, Jiancai

    2016-03-01

    An energy harvester using a piezoelectric unimorph based heterostructure is presented to convert stray power-frequency (50 Hz or 60 Hz) magnetic field energy into electrical energy. The harvester consists a piezoelectric unimorph and a U-shaped mass structure. The U-shaped mass structure with two parallel bar magnets leads to a large rotary inertia for the given proof mass. An enhanced exciting torque is induced on the unimorph and the response of the harvester to the external magnetic field is strengthened. Under the resonant frequency of 50 Hz, the harvester produces a power of 154.6 µW with a matching load resistance of 199 kΩ at a magnetic field of 0.5 Oe. Through an up-conversion management circuit, the energy harvester can successfully drive a wireless sensor node with high power consumption (90 mW at transmitting and 18 mW at receiving) at a duration of 205 ms. Note to the reader: The article number 30902 in PDF file was a mistake and has been corrected in 30903 on May 11, 2016.

  18. Energy Harvesting from the Stray Electromagnetic Field around the Electrical Power Cable for Smart Grid Applications

    Science.gov (United States)

    2016-01-01

    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. PMID:27579343

  19. The study of stray magnetic fields from digital recording heads for tape applications

    CERN Document Server

    Munro, T

    2000-01-01

    characteristics are presented. The results of the electron beam studies on the Emboss head and on the modified data head are discussed in Chapter 3. This chapter starts with a brief description of the samples. The preparations of the samples were carried out by Onstream to adapt them for electron microscopy and is discussed in this chapter. The study of stray magnetic fields from magnetic recording heads for tape applications was undertaken using the Differential Phase Contrast (DPC) mode of Lorentz microscopy and Magnetic Force Microscopy (MFM). Electron Beam Tomography (EBT), at Glasgow was derived from the DPC technique and this was carried out in a highly modified Philips CM20 (S)TEM; previous EBT work had been carried out using a modified JEOL 2000 FX. A Digital Instruments MFM 3100 equipped with an Extender Electronics Module was used to study a production data head and an experimental Emboss head supplied by Onstream. This thesis starts with a brief discussion of the basics of ferromagnetism and the ap...

  20. Energy Harvesting from the Stray Electromagnetic Field around the Electrical Power Cable for Smart Grid Applications

    Directory of Open Access Journals (Sweden)

    Farid Ullah Khan

    2016-01-01

    Full Text Available 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.

  1. 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.

  2. Exposure to static and time-varying magnetic fields from working in the static magnetic stray fields of MRI scanners : A comprehensive survey in the Netherlands

    NARCIS (Netherlands)

    Schaap, Kristel|info:eu-repo/dai/nl/323043216; Christopher-De Vries, Yvette; Crozier, Stuart; Vocht, Frank De; Kromhout, Hans|info:eu-repo/dai/nl/074385224

    2014-01-01

    Clinical and research staff who work around magnetic resonance imaging (MRI) scanners are exposed to the static magnetic stray fields of these scanners. Although the past decade has seen strong developments in the assessment of occupational exposure to electromagnetic fields from MRI scanners, there

  3. 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.

  4. Experimental Evidence of the Effect of a High Magnetic Field on the Stray Grains Formation in Cross-Section Change Region for Ni-Based Superalloy During Directional Solidification

    Science.gov (United States)

    Xuan, Weidong; Ren, Zhongming; Li, Chuanjun

    2015-04-01

    The effect of a high magnetic field on the stray grains in cross-section change region was investigated experimentally during directional solidification of superalloy. The microstructures showed that the high magnetic field significantly suppressed the stray grains formation in cross-section change region. Meanwhile, the temperature curves indicated that the nucleation undercooling was significantly increased in a high magnetic field. The effect of a high magnetic field on the stray grains was discussed based on the nucleation mechanism.

  5. Effects of near-source heterogeneity on wave fields emanating from crustal sources observed at regional and teleseismic distances

    Science.gov (United States)

    Avants, Megan S.

    Near-source path effects imprint the wave field emanating from a seismic source and, if not well resolved, can obscure the details of source characteristics determined from observations of the seismic waves at regional and teleseismic distances (≥200 km). These effects are particularly strong for crustal sources such as shallow earthquakes and underground nuclear explosions. First, I explore 2D effects of random seismic P-wave velocity heterogeneity resulting from volumetric heterogeneity in the upper mantle and variability of the Moho on the amplitude decay of the regional phase Pn. Results indicate that the pattern of amplitude decay due to geometric spreading for a simple Earth model is more complex than that for an Earth model containing strong heterogeneity in the mantle lid. Next, I implement the representation theorem in a method which collects displacement and strain components output from a 3D finite difference program capable of including realistic surface topography and geologic structure in a 3D velocity model, and calculates teleseismic 3D Green functions (3DGFs) to specified receiver locations. Green functions produced from a 3D source model match Green functions produced from a 1D source model for theoretical source-receiver geometries. This new method is then applied to the problem of constraining the source depth and location of the three nuclear tests conducted by North Korea, by using a realistic topography model for the mountainous test region to calculate 3DGFs for several possible locations of each event. Amplitude ratios of P and pP from 3DGFs are correlated to those in observed stacked traces. Results show a sensitivity of this method to source depth and location across the test site region with source depths slightly greater than published estimates, but relative locations consistent with other studies. Finally, I determine a rupture model of the 2008 Wenchuan earthquake using 3DGFs calculated in a velocity model containing the dramatic

  6. Sensitization of a stray-field NMR to vibrations: a potential for MR elastometry with a portable NMR sensor.

    Science.gov (United States)

    Mastikhin, Igor; Barnhill, Marie

    2014-11-01

    An NMR signal from a sample in a constant stray field of a portable NMR sensor is sensitized to vibrations. The CPMG sequence is synchronized to vibrations so that the constant gradient becomes an "effective" square-wave gradient, leading to the vibration-induced phase accumulation. The integrating nature of the spot measurement, combined with the phase distribution due to a non-uniform gradient and/or a wave field, leads to a destructive interference, the drop in the signal intensity and changes in the echo train shape. Vibrations with amplitudes as small as 140 nm were reliably detected with the permanent gradient of 12.4 T/m. The signal intensity depends on the phase offset between the vibrations and the pulse sequence. This approach opens the way for performing elastometry and micro-rheology measurements with portable NMR devices beyond the walls of a laboratory. Even without synchronization, if a vibration frequency is comparable to 1/2TE of the CPMG sequence, the signal can be severely affected, making it important for potential industrial applications of stray-field NMR. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Surface Casing Pressure As an Indicator of Well Integrity Loss and Stray Gas Migration in the Wattenberg Field, Colorado.

    Science.gov (United States)

    Lackey, Greg; Rajaram, Harihar; Sherwood, Owen A; Burke, Troy L; Ryan, Joseph N

    2017-03-21

    The risk of environmental contamination by oil and gas wells depends strongly on the frequency with which they lose integrity. Wells with compromised integrity typically exhibit pressure in their outermost annulus (surface casing pressure, SfCP) due to gas accumulation. SfCP is an easily measured but poorly documented gauge of well integrity. Here, we analyze SfCP data from the Colorado Oil and Gas Conservation Commission database to evaluate the frequency of well integrity loss in the Wattenberg Test Zone (WTZ), within the Wattenberg Field, Colorado. Deviated and horizontal wells were found to exhibit SfCP more frequently than vertical wells. We propose a physically meaningful well-specific critical SfCP criterion, which indicates the potential for a well to induce stray gas migration. We show that 270 of 3923 wells tested for SfCP in the WTZ exceeded critical SfCP. Critical SfCP is strongly controlled by the depth of the surface casing. Newer horizontal wells, drilled during the unconventional drilling boom, exhibited critical SfCP less frequently than other wells because they were predominantly constructed with deeper surface casings. Thus, they pose a lower risk for inducing stray gas migration than legacy vertical or deviated wells with surface casings shorter than modern standards.

  8. Competition between Superconductor - Ferromagnetic stray magnetic fields in YBa2Cu3O7-xfilms pierced with Co nano-rods.

    Science.gov (United States)

    Rouco, V; Córdoba, R; De Teresa, J M; Rodríguez, L A; Navau, C; Del-Valle, N; Via, G; Sánchez, A; Monton, C; Kronast, F; Obradors, X; Puig, T; Palau, A

    2017-07-18

    Superconductivity and ferromagnetism are two antagonistic phenomena that combined can lead to a rich phenomenology of interactions, resulting in novel physical properties and unique functionalities. Here we propose an original hybrid system formed by a high-temperature superconducting film, patterned with antidots, and with ferromagnetic nano-rods grown inside them. This particular structure exhibits the synergic influence of superconductor (SC) - ferromagnetic (FM) stray fields, in both the superconducting behaviour of the film and the three-dimensional (3D) magnetic structure of nano-rods. We show that FM stray fields directly influence the critical current density of the superconducting film. Additional functionalities appear due to the interaction of SC stray fields, associated to supercurrent loops, with the non-trivial 3D remanent magnetic structure of FM nano-rods. This work unravels the importance of addressing quantitatively the effect of stray magnetic fields from both, the superconductor and the ferromagnet in hybrid magnetic nano-devices based on high temperature superconductors.

  9. Occupational exposure of healthcare and research staff to static magnetic stray fields from 1.5-7 Tesla MRI scanners is associated with reporting of transient symptoms.

    NARCIS (Netherlands)

    Schaap, Kristel|info:eu-repo/dai/nl/323043216; Christopher-de Vries, Yvette; Mason, Catherine K; de Vocht, Frank; Portengen, Lützen|info:eu-repo/dai/nl/269224742; Kromhout, Hans|info:eu-repo/dai/nl/074385224

    2014-01-01

    OBJECTIVES: Limited data is available about incidence of acute transient symptoms associated with occupational exposure to static magnetic stray fields from MRI scanners. We aimed to assess the incidence of these symptoms among healthcare and research staff working with MRI scanners, and their

  10. Intercomparison of radiation protection devices in a high-energy stray neutron field. Part III: Instrument response

    Energy Technology Data Exchange (ETDEWEB)

    Silari, M., E-mail: marco.silari@cern.c [CERN, 1211 Geneva 23 (Switzerland); Agosteo, S. [Politecnico of Milano, Dipartimento di Energia, piazza Leonardo da Vinci 32, 20133 Milano (Italy); Beck, P. [ARC, Austrian Research Centers GmbH-ARC, 2444 Seibersdorf (Austria); Bedogni, R. [INFN-LNF, Via E. Fermi 40, 00044 Frascati (Italy); Cale, E. [Institut de Radioprotection et Surete Nucleaire, BP 17, 92262 Fontenay aux Roses (France); Caresana, M. [Politecnico of Milano, Dipartimento di Energia, piazza Leonardo da Vinci 32, 20133 Milano (Italy); Domingo, C. [Grup de Fisica de les Radiacions, Departament de Fisica, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Donadille, L.; Dubourg, N. [Institut de Radioprotection et Surete Nucleaire, BP 17, 92262 Fontenay aux Roses (France); Esposito, A. [INFN-LNF, Via E. Fermi 40, 00044 Frascati (Italy); Fehrenbacher, G. [GSI, Planckstrasse 1, 64291 Darmstadt (Germany); Fernandez, F. [Grup de Fisica de les Radiacions, Departament de Fisica, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Ferrarini, M. [Politecnico of Milano, Dipartimento di Energia, piazza Leonardo da Vinci 32, 20133 Milano (Italy); Fiechtner, A.; Fuchs, A. [Paul Scherrer Institut, 5232 Villigen (Switzerland); Garcia, M.J. [Grup de Fisica de les Radiacions, Departament de Fisica, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Golnik, N. [Institute of Atomic Energy, 05-400 Otwock-Swierk (Poland); Gutermuth, F. [GSI, Planckstrasse 1, 64291 Darmstadt (Germany); Khurana, S.; Klages, Th. [Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig (Germany)

    2009-08-15

    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.

  11. Work-related factors associated with occupational exposure to static magnetic stray fields from MRI scanners

    NARCIS (Netherlands)

    Schaap, Kristel|info:eu-repo/dai/nl/323043216; Christopher-De Vries, Yvette; Cambron-Goulet, Évelyne; Kromhout, Hans|info:eu-repo/dai/nl/074385224

    2016-01-01

    PURPOSE: This study aims to identify work-related and personal factors associated with workers' exposure to static magnetic fields (SMF) and motion-induced time-varying magnetic fields (TVMF) from MRI scanners. METHODS: Measurements of personal exposure to SMF and TVMF were performed among MRI staff

  12. 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.

  13. 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...... unit, and the dose equivalent between 0.4 and 9 μSv per monitor unit, depending on beam energy and measurement position. In the proton beam the stray absorbed dose ranged between 3 and 135 μGy per prescribed Gy, depending on detector position and primary proton energy....

  14. 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

  15. Monitoring of Cellular Changes in the Bone Marrow following PTH(1-34 Treatment of OVX Rats Using a Portable Stray-Field NMR Scanner

    Directory of Open Access Journals (Sweden)

    Inbar Hillel

    2017-01-01

    Full Text Available Osteoporosis is characterized by reduction in trabecular bone in conjunction with increased marrow cell adiposity. While these changes occur within weeks, monitoring of treatment efficacy as performed by DEXA is sensitive only to long-term changes. MRI is sensitive to bone marrow changes but is less affordable. In a recent study, we have shown that a stray-field NMR can monitor bone marrow cellular changes that are related to osteoporosis. Objectives. To demonstrate sensitivity of a low-field tabletop NMR scanner to bone marrow dynamics following hormonal treatment in rats. Methods. Two-month-old female rats (n=36 were ovariectomized (OVX and dosed for the ensuing 3 or 5 weeks with 20 mg/kg of PTH(1-34. Hind limbs femurs and tibiae were isolated and underwent ex vivo microradiography and histology and NMR relaxometry at 6 weeks (preventive experiment and 11 weeks (therapeutic treatment experiment after OVX. Results. OVX rats developed osteoporotic changes including adipogenic marrow compared to Sham and PTH treated rats. T2 and ADC NMR relaxation coefficients were found to correlate with marrow composition. Conclusions. This study suggests that stray-field NMR, an affordable method that is sensitive to the rapid cellular changes in bone marrow, may have a clinical value in monitoring hormonal treatment for osteoporosis.

  16. Monitoring of Cellular Changes in the Bone Marrow following PTH(1-34) Treatment of OVX Rats Using a Portable Stray-Field NMR Scanner.

    Science.gov (United States)

    Hillel, Inbar; Binderman, Itzhak; Sarda, Yifat; Nevo, Uri

    2017-01-01

    Osteoporosis is characterized by reduction in trabecular bone in conjunction with increased marrow cell adiposity. While these changes occur within weeks, monitoring of treatment efficacy as performed by DEXA is sensitive only to long-term changes. MRI is sensitive to bone marrow changes but is less affordable. In a recent study, we have shown that a stray-field NMR can monitor bone marrow cellular changes that are related to osteoporosis. Objectives. To demonstrate sensitivity of a low-field tabletop NMR scanner to bone marrow dynamics following hormonal treatment in rats. Methods. Two-month-old female rats (n = 36) were ovariectomized (OVX) and dosed for the ensuing 3 or 5 weeks with 20 mg/kg of PTH(1-34). Hind limbs femurs and tibiae were isolated and underwent ex vivo microradiography and histology and NMR relaxometry at 6 weeks (preventive experiment) and 11 weeks (therapeutic treatment experiment) after OVX. Results. OVX rats developed osteoporotic changes including adipogenic marrow compared to Sham and PTH treated rats. T2 and ADC NMR relaxation coefficients were found to correlate with marrow composition. Conclusions. This study suggests that stray-field NMR, an affordable method that is sensitive to the rapid cellular changes in bone marrow, may have a clinical value in monitoring hormonal treatment for osteoporosis.

  17. Exposure to static and time-varying magnetic fields from working in the static magnetic stray fields of MRI scanners: a comprehensive survey in the Netherlands.

    Science.gov (United States)

    Schaap, Kristel; Christopher-De Vries, Yvette; Crozier, Stuart; De Vocht, Frank; Kromhout, Hans

    2014-11-01

    Clinical and research staff who work around magnetic resonance imaging (MRI) scanners are exposed to the static magnetic stray fields of these scanners. Although the past decade has seen strong developments in the assessment of occupational exposure to electromagnetic fields from MRI scanners, there is insufficient insight into the exposure variability that characterizes routine MRI work practice. However, this is an essential component of risk assessment and epidemiological studies. This paper describes the results of a measurement survey of shift-based personal exposure to static magnetic fields (SMF) (B) and motion-induced time-varying magnetic fields (dB/dt) among workers at 15 MRI facilities in the Netherlands. With the use of portable magnetic field dosimeters, >400 full-shift and partial shift exposure measurements were collected among various jobs involved in clinical and research MRI. Various full-shift exposure metrics for B and motion-induced dB/dt exposure were calculated from the measurements, including instantaneous peak exposure and time-weighted average (TWA) exposures. We found strong correlations between levels of static (B) and time-varying (dB/dt) exposure (r = 0.88-0.92) and between different metrics (i.e. peak exposure, TWA exposure) to express full-shift exposure (r = 0.69-0.78). On average, participants were exposed to MRI-related SMFs during only 3.7% of their work shift. Average and peak B and dB/dt exposure levels during the work inside the MRI scanner room were highest among technical staff, research staff, and radiographers. Average and peak B exposure levels were lowest among cleaners, while dB/dt levels were lowest among anaesthesiology staff. Although modest exposure variability between workplaces and occupations was observed, variation between individuals of the same occupation was substantial, especially among research staff. This relatively large variability between workers with the same job suggests that exposure classification

  18. 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.

  19. 1H stray-field long spin-echo trains and MRI: novel studies on the photopolymerization of a commercial dental resin

    Science.gov (United States)

    Nunes, Teresa G.; Guillot, Geneviève; Pereira, Sónia G.; Pires, Ricardo

    2002-06-01

    Photopolymerization of a commercial dental resin has been investigated by 1H stray-field (STRAFI) magnetic resonance. The resin is a visible light-cured system, included in a new generation adhesive, which is used to bond the restorative material to enamel or dentin. Different methods were used to follow the curing reaction, which involve long and short spin-echo train acquisitions to obtain one-slice and one-dimensional data, respectively. The echo attenuation, in the limit of very short time delays, could be described as the sum of two exponentials. While the intensity of the early echoes in the train appeared mainly governed by spin-spin relaxation, the decay of the last echoes seemed to depend also on spin-lattice relaxation in the rotating frame. The relative amplitude of the long-time component was found to decrease from 84% to 10% with the photopolymerization progress, and a STRAFI degree of conversion of 74% could thus be suggested. The influence of the curing protocol was observed in STRAFI profiles.

  20. Occupational exposure of healthcare and research staff to static magnetic stray fields from 1.5–7 Tesla MRI scanners is associated with reporting of transient symptoms

    Science.gov (United States)

    Schaap, Kristel; Christopher-de Vries, Yvette; Mason, Catherine K; de Vocht, Frank; Portengen, Lützen; Kromhout, Hans

    2014-01-01

    Objectives Limited data is available about incidence of acute transient symptoms associated with occupational exposure to static magnetic stray fields from MRI scanners. We aimed to assess the incidence of these symptoms among healthcare and research staff working with MRI scanners, and their association with static magnetic field exposure. Methods We performed an observational study among 361 employees of 14 clinical and research MRI facilities in The Netherlands. Each participant completed a diary during one or more work shifts inside and/or outside the MRI facility, reporting work activities and symptoms (from a list of potentially MRI-related symptoms, complemented with unrelated symptoms) experienced during a working day. We analysed 633 diaries. Exposure categories were defined by strength and type of MRI scanner, using non-MRI shifts as the reference category for statistical analysis. Non-MRI shifts originated from MRI staff who also participated on MRI days, as well as CT radiographers who never worked with MRI. Results Varying per exposure category, symptoms were reported during 16–39% of the MRI work shifts. We observed a positive association between scanner strength and reported symptoms among healthcare and research staff working with closed-bore MRI scanners of 1.5 Tesla (T) and higher (1.5 T OR=1.88; 3.0 T OR=2.14; 7.0 T OR=4.17). This finding was mainly driven by reporting of vertigo and metallic taste. Conclusions The results suggest an exposure-response association between exposure to strong static magnetic fields (and associated motion-induced time-varying magnetic fields) and reporting of transient symptoms on the same day of exposure. Trial registration number 11-032/C PMID:24714654

  1. Visualizing stray light

    Science.gov (United States)

    Barron, Don R.

    1996-08-01

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

  2. Intercomparison of radiation protection devices in a high-energy stray neutron field. Part II: Bonner sphere spectrometry

    CERN Document Server

    Wiegel, B; Bedogni, R; Caresana, M; Esposito, A; Fehrenbacher, G; Ferrarini, M; Hohmann, E; Hranitzky, C; Kasper, A; Khurana, S; Mares, V; Reginatto, M; Rollet, S; Rühm, W; Schardt, D; Silari, M; Simmer, G; Weitzenegger, E

    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. A major task of the CONRAD Work Package “complex mixed radiation fields at workplaces” was to organise a benchmark exercise in a workplace field at a high-energy particle accelerator where neutrons are the dominant radiation component. The CONRAD benchmark exercise took place at the Gesellschaft für Schwerionenforschung mbH (GSI) in Darmstadt, Germany in July 2006. In this paper, the results of the spectrometry using four extended -range Bonner sphere spectrometers of four different institutes are reported. Outside Cave A the neutron spectra were measured with three spectrometers at six selected positions and ambient dose equivalent values were derived for use in the intercomparison with other area monitors and dosemeters. At a common position all three spectrometers were used to allow a direct comparison of their results which acts as an int...

  3. Intercomparison of radiation protection devices in a high-energy stray neutron field, Part II: Bonner sphere spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Wiegel, B., E-mail: burkhard.wiegel@ptb.d [Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig (Germany); Agosteo, S. [Politecnico of Milano, Dipartimento di Energia, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Bedogni, R. [INFN Laboratori Nazionali di Frascati, Via E. Fermi 40, 00044 Frascati (Italy); Caresana, M. [Politecnico of Milano, Dipartimento di Energia, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Esposito, A. [INFN Laboratori Nazionali di Frascati, Via E. Fermi 40, 00044 Frascati (Italy); Fehrenbacher, G. [Gesellschaft fuer Schwerionenforschung mbH, Planckstrasse 1, 64291 Darmstadt (Germany); Ferrarini, M. [Politecnico of Milano, Dipartimento di Energia, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Hohmann, E. [Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig (Germany); Hranitzky, C. [Austrian Research Centers GmbH-ARC, 2444 Seibersdorf (Austria); Kasper, A.; Khurana, S. [Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig (Germany); Mares, V. [Helmholtz Zentrum Muenchen, German Research Center for Environmental Health (GmbH), Ingolstaedter Landstrasse 1, 85764 Neuherberg (Germany); Reginatto, M. [Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig (Germany); Rollet, S. [Austrian Research Centers GmbH-ARC, 2444 Seibersdorf (Austria); Ruehm, W. [Helmholtz Zentrum Muenchen, German Research Center for Environmental Health (GmbH), Ingolstaedter Landstrasse 1, 85764 Neuherberg (Germany); Schardt, D. [Gesellschaft fuer Schwerionenforschung mbH, Planckstrasse 1, 64291 Darmstadt (Germany); Silari, M. [CERN, 1211 Geneva 23 (Switzerland); Simmer, G.; Weitzenegger, E. [Helmholtz Zentrum Muenchen, German Research Center for Environmental Health (GmbH), Ingolstaedter Landstrasse 1, 85764 Neuherberg (Germany)

    2009-08-15

    The European Commission has funded within its 6th Framework Programme a three-year project (2005-2007) called CONRAD, COordinated Network for RAdiation Dosimetry. A major task of the CONRAD Work Package 'complex mixed radiation fields at workplaces' was to organise a benchmark exercise in a workplace field at a high-energy particle accelerator where neutrons are the dominant radiation component. The CONRAD benchmark exercise took place at the Gesellschaft fuer Schwerionenforschung mbH (GSI) in Darmstadt, Germany in July 2006. In this paper, the results of the spectrometry using four extended -range Bonner sphere spectrometers of four different institutes are reported. Outside Cave A the neutron spectra were measured with three spectrometers at six selected positions and ambient dose equivalent values were derived for use in the intercomparison with other area monitors and dosemeters. At a common position all three spectrometers were used to allow a direct comparison of their results which acts as an internal quality assurance. The comparison of the neutron spectra measured by the different groups shows very good agreement. A detailed analysis presents some differences between the shapes of the spectra and possible sources of these differences are discussed. However, the ability of Bonner sphere spectrometers to provide reliable integral quantities like fluence and ambient dose equivalent is well demonstrated in this exercise. The fluence and dose results derived by the three groups agree very well within the given uncertainties, not only with respect to the total energy region present in this environment but also for selected energy regions which contribute in certain strength to the total values. In addition to the positions outside Cave A one spectrometer was used to measure the neutron spectrum at one position in the entry maze of Cave A. In this case a comparison was possible to earlier measurements.

  4. Detection of bone marrow changes related to estrogen withdrawal in rats with a tabletop stray-field NMR scanner.

    Science.gov (United States)

    Sarda, Yifat; Bergman, Elad; Hillel, Inbar; Binderman, Itzhak; Nevo, Uri

    2017-09-01

    Osteoporosis is characterized by a decrease in bone mineral density (BMD). A preliminary stage of the disease is progressive bone marrow adiposity, caused by imbalance between osteogenesis and adipogenesis in the marrow. Detection of osteoporosis relies on the quantification of BMD with techniques such as dual-energy X-ray absorptiometry. This work aimed to detect bone marrow changes in an experimental model of osteopenia using a low-field tabletop NMR scanner. An experiment was performed on 32 female rats, 3 months old, 16 of which were ovariectomized (OVX) and 16 were sham-operated (sham). The femur and tibia from both hind limbs were isolated and underwent ex vivo NMR scans at four time points after the OVX and sham operations. NMR scans were complemented by BMD measurements and histology. Significant changes in the bone marrow of ovariectomized rats, relative to sham operated rats, were observed after 3.5 and 4.5 months. Bone marrow adiposity was detected by significant changes in T1 and T2 relaxation times, and in the diffusion coefficient. This study suggests a potential detection of changes to the bone marrow using a tabletop NMR device. Clinical translation may facilitate screening, early detection of bone weakening as a result of estrogen withdrawal, and monitoring of treatment efficacy. Magn Reson Med 78:860-870, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  5. Radon sources emanation in granitic soil and saprolite

    Energy Technology Data Exchange (ETDEWEB)

    Wollenberg, H.; Flexser, S. [Lawrence Berkeley Lab., CA (United States); Brimhall, G.; Lewis, C. [California Univ., Berkeley, CA (United States). Dept. of Geology and Geophysics

    1993-08-01

    Petrological and geochemical examinations of soil, saprolite, and quartz diorite protolith have been made at the Small Structures field site, Ben Lomond Mountain, California. Variations in Ra in soil and saprolite are mainly controlled by heterogeneities inherited from the parent quartz diorite. Fission-track radiography shows that U is concentrated in the primary accessory minerals, zircon and sphene. However, most importantly for Rn emanation, U is also concentrated in secondary sites: weathered sphene, biotite and plagioclase, grain coatings, and Fe-rich fracture linings which also contain a rare-earth phosphate mineral. This occurrence of U along permeable fracture zones suggests that soil-gas Rn from depth (> 2 m) is a significant contributor to Rn availability near the surface. Zones highest in emanation occur where fine pedogenic phases: gibbsite, amorphous silica, and iron oxyhydroxide are most abundant. Mass balance analyses of this soil-saprolite profile are in progress and preliminary indicate that a high-emanation zone corresponds to the upper portion of a zone of accumulation of U and Ba.

  6. Stray light and tolerance analysis of an ultrathin waveguide display.

    Science.gov (United States)

    Wang, Qiwei; Cheng, Dewen; Hou, Qichao; Hu, Yuan; Wang, Yongtian

    2015-10-01

    Waveguides are becoming increasingly popular in the field of near-eye display because of their low thickness and light weight. However, ghost stray light generated in the waveguide and the double-image problem caused by low parallelism precision seriously degrade the display quality. In this study, the causes of stray light are investigated, an effective solution is proposed, and a coupling-in structure is designed to suppress stray light. The Monte Carlo tolerances on the parallelism errors based on the visual acuity for the two substrates and the partially reflective mirror array (PRMA) of the waveguide are implemented. Results show that the fabrication accuracy of the substrates and the PRMA should be controlled within 6'' and 9'', respectively. A 2.4 mm thick waveguide with stray light of less than 1% is designed. The field of view is 36° in the pupil-expanding direction, and the diameter of the exit pupil is 11.6 mm at an eye relief of 20 mm. Finally, a proof-of-concept prototype is fabricated and demonstrated.

  7. Rabies Vaccination Targets for Stray Dog Populations

    Science.gov (United States)

    Leung, Tiffany; Davis, Stephen A.

    2017-01-01

    The role of stray dogs in the persistence of domestic dog rabies, and whether removal of such dogs is beneficial, remains contentious issues for control programs seeking to eliminate rabies. While a community might reach the WHO vaccination target of 70% for dogs that can be handled, the stray or neighborhood dogs that are too wary of humans to be held are a more problematic population to vaccinate. Here, we present a method to estimate vaccination targets for stray dogs when the dog population is made up of stray, free-roaming, and confined dogs, where the latter two types are considered to have an identifiable owner. The control effort required for stray dogs is determined by the type-reproduction number, T1, the number of stray dogs infected by one rabid stray dog either directly or via any chain of infection involving owned dogs. Like the basic reproduction number R0 for single host populations, T1 determines the vaccination effort required to control the spread of disease when control is targeted at one host type, and there is a mix of host types. The application of T1 to rabies in mixed populations of stray and owned dogs is novel. We show that the outcome is sensitive to the vaccination coverage in the owned dog population, such that if vaccination rates of owned dogs were too low then no control effort targeting stray dogs is able to control or eliminate rabies. The required vaccination level also depends on the composition of the dog population, where a high proportion of either stray or free-roaming dogs implies unrealistically high vaccination levels are required to prevent rabies. We find that the required control effort is less sensitive to continuous culling that increases the death rate of stray dogs than to changes in the carrying capacity of the stray dog population. PMID:28451589

  8. 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.

  9. Telescope stray light: early experience with SOFIA

    Science.gov (United States)

    Waddell, Patrick; Becklin, Eric E.; Hamilton, Ryan T.; Vacca, William D.; Lachenmann, Michael

    2016-09-01

    Effective stray light control is a key requirement for wide dynamic range performance of scientific optical and infrared systems. SOFIA now has over 325 mission flights including extended southern hemisphere deployments; science campaigns using 7 different instrument configurations have been completed. The research observations accomplished on these missions indicate that the telescope and cavity designs are effective at suppressing stray light. Stray light performance impacts, such as optical surface contamination, from cavity environment conditions during mission flight cycles and while on-ground, have proved to be particularly benign. When compared with earlier estimates, far fewer large optics re-coatings are now anticipated, providing greater facility efficiency.

  10. Analysis and Reduction of Stray-Current Attack in Reciprocated Traveling Wire Electrochemical Machining

    Directory of Open Access Journals (Sweden)

    Yongbin Zeng

    2014-07-01

    Full Text Available Traveling wire electrochemical machining is a promising approach for the fabrication of various metal parts. However, the stray-current attack deteriorates the surface quality while it is employed to cut thick workpiece as a normal pulse or DC is used. In this paper, the characteristics of the stray-current attack in reciprocated traveling wire electrochemical machining are firstly identified, and special insulating methods are proposed to reduce the effect of the stray-current. The model of electric field is built. Both the simulation and the experimental results illustrate that the stray-current attack can be reduced significantly by the proposed insulating methods. Finally, structures with fine surface quality on stainless steel 304 with thickness of 20 mm were successfully produced.

  11. Stray light evaluation for the astrometric gravitation probe mission

    Science.gov (United States)

    Landini, Federico; Riva, Alberto; Gai, Mario; Baccani, Cristian; Focardi, Mauro; Pancrazzi, Maurizio

    2016-08-01

    The main goal of the Astrometric Gravitation Probe mission is the verification of General Relativity and competing gravitation theories by precise astrometric determination of light deflection, and of orbital parameters of selected Solar System objects. The key element is the coherent combination of a set of 92 circular entrance apertures, each feeding an elementary inverted occulter similar to the one developed for Solar Orbiter/METIS.1 This provides coronagraphic functions over a relevant field of view, in which all stars are observed for astrometric purposes with the full resolution of a 1 m diameter telescope. The telescope primary mirror acts as a beam combiner, feeding the 92 pupils, through the internal optics, toward a single focal plane. The primary mirror is characterized by 92 output apertures, sized according to the entrance pupil and telescope geometry, in order to dump the solar disk light beyond the instrument. The astronomical objects are much fainter than the solar disk, which is angularly close to the inner field of view of the telescope. The stray light as generated by the diffraction of the solar disk at the edges of the 92 apertures defines the limiting magnitude of observable stars. In particular, the stray light due to the diffraction from the pupil apertures is scattered by the telescope optics and follows the same optical path of the astronomical objects; it is a contribution that cannot be eliminated and must therefore be carefully evaluated. This paper describes the preliminary evaluation of this stray light contribution.

  12. Stray dog meat consumption and rebies

    African Journals Online (AJOL)

    Sir, the recent report on “stray dog trade, dog meat consumption and rabies” is very interesting [1]. Ekanem et al. noted that “: stray dog trade, fuelled by eating of dog meat, is a risk factor for human and animal rabies in Calabar, southern Nigeria [1].” In fact, eating of dog meat is not a usual way that rabies can be transmitted ...

  13. Radon emanation from backfilled mill tailings in underground uranium mine.

    Science.gov (United States)

    Sahu, Patitapaban; Mishra, Devi Prasad; Panigrahi, Durga Charan; Jha, Vivekananda; Patnaik, R Lokeswara; Sethy, Narendra Kumar

    2014-04-01

    Coarser mill tailings used as backfill to stabilize the stoped out areas in underground uranium mines is a potential source of radon contamination. This paper presents the quantitative assessment of radon emanation from the backfilled tailings in Jaduguda mine, India using a cylindrical accumulator. Some of the important parameters such as (226)Ra activity concentration, bulk density, bulk porosity, moisture content and radon emanation factor of the tailings affecting radon emanation were determined in the laboratory. The study revealed that the radon emanation rate of the tailings varied in the range of 0.12-7.03 Bq m(-2) s(-1) with geometric mean of 1.01 Bq m(-2) s(-1) and geometric standard deviation of 3.39. An increase in radon emanation rate was noticed up to a moisture saturation of 0.09 in the tailings, after which the emanation rate gradually started declining with saturation due to low diffusion coefficient of radon in the saturated tailings. Radon emanation factor of the tailings varied in the range of 0.08-0.23 with the mean value of 0.21. The emanation factor of the tailings with moisture saturation level over 0.09 was found to be about three times higher than that of the absolutely dry tailings. The empirical relationship obtained between (222)Rn emanation rate and (226)Ra activity concentration of the tailings indicated a significant positive linear correlation (r = 0.95, p < 0.001). This relationship may be useful for quick prediction of radon emanation rate from the backfill material of similar nature. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Stray light effects in above-water remote-sensing reflectance from hyperspectral radiometers.

    Science.gov (United States)

    Talone, Marco; Zibordi, Giuseppe; Ansko, Ilmar; Banks, Andrew Clive; Kuusk, Joel

    2016-05-20

    Stray light perturbations are unwanted distortions of the measured spectrum due to the nonideal performance of optical radiometers. Because of this, stray light characterization and correction is essential when accurate radiometric measurements are a necessity. In agreement with such a need, this study focused on stray light correction of hyperspectral radiometers widely applied for above-water measurements to determine the remote-sensing reflectance (RRS). Stray light of sample radiometers was experimentally characterized and a correction algorithm was developed and applied to field measurements performed in the Mediterranean Sea. Results indicate that mean stray light corrections are appreciable, with values generally varying from -1% to +1% in the 400-700 nm spectral region for downward irradiance and sky radiance, and from -1% to +4% for total radiance from the sea. Mean corrections for data products such as RRS exhibit values that depend on water type varying between -0.5% and +1% in the blue-green spectral region, with peaks up to 9% in the red in eutrophic waters. The possibility of using one common stray light correction matrix for the analyzed class of radiometers was also investigated. Results centered on RRS support such a feasibility at the expense of an increment of the uncertainty typically well below 0.5% in the blue-green and up to 1% in the red, assuming sensors are based on spectrographs from the same production batch.

  15. God's Unlikely Comeback: Evolution, Emanation, and Ecology

    Directory of Open Access Journals (Sweden)

    Seán O Nualláin

    2012-05-01

    Full Text Available This paper has three contrasting sections. The first starts with a description of the academic context that has led researchers like Stuart Kauffman to introduce “God” into respectable discourse. It then goes on to juxtapose his schema with similar others that his work does not reference. It is proposed that, since humanity is the cutting edge-for good and evil-of emanation/revolution, it is human development that we must focus on. This, in turn cannot properly be discussed without reference to first person descriptions and their contrast with third person descriptions. Likewise the role of those contrasting accounts within and outside the academy, which is currently under threat, must be referred to.Accordingly, the second section begins with the delineation of subjectivity suggested by current neuroscience. It is argued that the cluster sampling of EEG will yield significantly more meaningful results than other competing methods. This paper makes the admittedly radical contention that it may be intellectually responsible to engage in forms of thought and practice that engage the whole of life in a manner heretofore addressed by “religions”. Such forms of life cannot responsibly emerge from an insight into the nature of physical reality, which is the province of the academy. Rather, these forms emerge from consideration of the human psychophysical unity as it engages with a succession of different contexts and attempts to reflect on and refine its responses to them.The nature of the academy early in the 21st century is a confounding factor. The corporate pressure to attenuate academic freedom is real, as is the fact that academic freedom in liberal democracies would immediately migrate to other, initially unfunded structures in civil society with the internet offering myriad opportunities for dissemination and immediate critique of ideas. Orthogonal to this is the attempt to specify and refine one’s psychological life, the bane of

  16. Pyrotechnic Simulator/Stray-Voltage Detector

    Science.gov (United States)

    Greenfield, Terry

    2009-01-01

    The concept for a dual test item has been developed for use in simulating live initiators/detonators during ground testing to verify the proper operation of the safing and firing circuitry for ground and flight systems ordnance as well as continuous monitoring for any stray voltages. Previous ordnance simulators have consisted of fuses, flash bulbs, inert devices with bridge wires, and actual live ordnance items mounted in test chambers. Stray voltage detectors have included devices connected to the firing circuits for continuous monitoring and a final no-voltage test just prior to ordnance connection. The purpose of this combined ordnance simulation and stray-voltage detection is to provide an improved and comprehensive method to ensure the ordnance circuitry is verified safe and operational.

  17. Toxoplasma gondii Infection in Stray Cats

    Directory of Open Access Journals (Sweden)

    M Arbabi

    2007-04-01

    Full Text Available Background: Cat as definitive host of Toxoplasma gondii is important in the epidemiology of toxoplasmosis. The object of this study was to determine the seroprevalence of T. gondii as well as parasite isolation from faeces and brain tissues of stray cats in Kashan, central Iran. Methods: The prevalence of T. gondii was determined in serum, feces and brain tissue of 50 stray cats. IgG specific antibody to T. gondii was assessed by indirect fluorecent antibody test (IFAT. Results: Overall infection rate was 86% in 1:20 to1:640 titers. The highest percentage (22% was for 1:160 and the least (6% were for 1: 640. T. gondii tissue cyst isolated from 2(4% cats by bioassay in mice. No oocysts detected from cat stool by direct and concentration methods. Conclusion: This study showed that the prevalence of T. gondii in stray cats is high in Kashan region.

  18. Stray light of spectacle lenses compared with stray light in the eye.

    Science.gov (United States)

    De Wit, Gerard C; Coppens, Joris E

    2003-05-01

    Stray light in spectacle lenses may affect the overall vision. It may also affect the measurement of ocular stray light, contrast sensitivity, or glare sensitivity. This article describes common stray light characteristics for glass and plastic spectacle lenses and compares this to the stray light characteristics of the eye, which are well known from the literature. Stray light is described by the skirts of the point-spread function (PSF), which were measured for angles from 4 degrees to 30 degrees. The PSF of spectacle lenses appears to follow the equation PSF = a(10). (theta/10)b, with a(10) and b representing fitting parameters and theta representing the stray light angle. The slope b is on average -2, which similar to that of the eye. For clean spectacle lenses, the PSF is usually at least an order of magnitude lower than that of the eye, whereas "as worn" (uncleaned) spectacle lenses may approach the PSF of the eye. To reach the PSF of the eye, the spectacle lens needs to be contaminated by as much as one or two fingerprints. The article also shows that plastic spectacle lenses degrade much faster than glass spectacle lenses when looking at the amount of stray light.

  19. 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.

  20. Clipboard: Restraining the enhancers from straying

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Biosciences; Volume 39; Issue 5. Clipboard: Restraining the enhancers from straying. Rakesh K Mishra. Volume 39 Issue 5 December 2014 pp 739-740. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/jbsc/039/05/0739-0740. Keywords. Boundary ...

  1. Stray radiation dose and second cancer risk for a pediatric patient receiving craniospinal irradiation with proton beams

    Science.gov (United States)

    Taddei, Phillip J.; Mirkovic, Dragan; Fontenot, Jonas D.; Giebeler, Annelise; Zheng, Yuanshui; Kornguth, David; Mohan, Radhe; Newhauser, Wayne D.

    2009-04-01

    Proton beam radiotherapy unavoidably exposes healthy tissue to stray radiation emanating from the treatment unit and secondary radiation produced within the patient. These exposures provide no known benefit and may increase a patient's risk of developing a radiogenic cancer. The aims of this study were to calculate doses to major organs and tissues and to estimate second cancer risk from stray radiation following craniospinal irradiation (CSI) with proton therapy. This was accomplished using detailed Monte Carlo simulations of a passive-scattering proton treatment unit and a voxelized phantom to represent the patient. Equivalent doses, effective dose and corresponding risk for developing a fatal second cancer were calculated for a 10-year-old boy who received proton therapy. The proton treatment comprised CSI at 30.6 Gy plus a boost of 23.4 Gy to the clinical target volume. The predicted effective dose from stray radiation was 418 mSv, of which 344 mSv was from neutrons originating outside the patient; the remaining 74 mSv was caused by neutrons originating within the patient. This effective dose corresponds to an attributable lifetime risk of a fatal second cancer of 3.4%. The equivalent doses that predominated the effective dose from stray radiation were in the lungs, stomach and colon. These results establish a baseline estimate of the stray radiation dose and corresponding risk for a pediatric patient undergoing proton CSI and support the suitability of passively-scattered proton beams for the treatment of central nervous system tumors in pediatric patients.

  2. Effect of internal wall covers on radon emanation inside houses

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Jarad, F.; Fremlin, J.H.

    1983-03-01

    Most types of paint for the internal walls of houses will reduce radon emanation from building materials. At the same time, the effect of paint will increase the concentration of radon inside the material itself and will increase the radon emanation from unpainted areas. One type of wall paper contains 6 and 0.3 ppm of uranium in its decorated and undecorated surfaces, respectively, the colouring being the main source of uranium. Other wallpapers appear to be free from uranium. Wallpaper, gypsum and plaster may increase the radon activity inside houses depending on their radium contents.

  3. OCULAR SONOGRAM OF INDONESIAN STRAY CAT EYES

    Directory of Open Access Journals (Sweden)

    Mokhamad Fakhrul Ulum

    2017-08-01

    Full Text Available The purpose of this study was to investigate Indonesian stray cat (KLI eyes by transpalpebrae B-mode ultrasound imaging. Eight healthy adult stray cats with 3.0-4.0 kg body weight were underwent of eyes ultrasound scanning without anesthesia or sedation. Linear ultrasound transducer with 7.5-15 MHz of frequency and ultrasound-gel were adhered directly to palpebral on the closed eyes. The results showed that the internal architecture of eyes was visible in different echogenicity according to the constituent of eyes structure. The sonograms with hypoechoic to hyperechoic parts of eyes were cornea, iris, cilliary body, suspensor ligament, sclera, and lens capsule. Moreover, anechoic parts of sonograms that having aqueous constituent were anterior chamber, posterior chamber, and vitreous humor. Based on the result, it can be concluded that B-mode ultrasound was able to assess the eyes through transpalpebral scanning.

  4. Discharge of water containing waste emanating from land to the ...

    African Journals Online (AJOL)

    The National Water Act, 1998 (Act 36 of 1998) mandates the Department of Water Affairs and Forestry to manage all water containing waste (wastewater), which emanates from land-based sources and which directly impact on the marine environment. These sources include sea outfalls, storm water drains, canals, rivers ...

  5. A micromegas detector for {sup 222}Rn emanations measurements

    Energy Technology Data Exchange (ETDEWEB)

    García, J. A.; Garza, J. G.; Irastorza, I. G.; Mirallas, H. [Laboratorio de Física Nuclear y Altas Energías, Universidad de Zaragoza, Zaragoza (Spain)

    2013-08-08

    The {sup 222}Rn emanation has significant contribution in the overall background for rare event searches experiments. In order to measure this emanations a high sensitivity detector has been designed. The detection method is based on the electrostatic collection of the {sup 222}Rn daughters on a Micromegas detector. Using a chamber with a volume of 21.2 l for the collection of {sup 218}Po and {sup 214}Po progeny of {sup 222}Rn and a 12 × 12cm{sup 2} pixelized Micromegas for the α detection. The advantages of the Micromegas detectors are the low intrinsic radioactivity and the track reconstruction of the α’s, having excellent capabilities for event discrimination.

  6. Newton's Metaphysics of Space as God's Emanative Effect

    Science.gov (United States)

    Jacquette, Dale

    2014-09-01

    In several of his writings, Isaac Newton proposed that physical space is God's "emanative effect" or "sensorium," revealing something interesting about the metaphysics underlying his mathematical physics. Newton's conjectures depart from Plato and Aristotle's metaphysics of space and from classical and Cambridge Neoplatonism. Present-day philosophical concepts of supervenience clarify Newton's ideas about space and offer a portrait of Newton not only as a mathematical physicist but an independent-minded rationalist philosopher.

  7. Effect of Over Zone Feeding on Rail Potential and Stray Current in DC Mass Transit System

    Directory of Open Access Journals (Sweden)

    Guifu Du

    2016-01-01

    Full Text Available DC traction power system with running rails as reflux conductor has been adopted in Guangzhou Metro Line 8. During the operation of the Guangzhou Metro Line, a high rail potential has been observed, and the leakage of stray current increases significantly. Because of the electrical connectivity of the catenary, over zone feeding of traction current may exist when multiple trains run in multiple traction substations. Guangzhou Metro Line 8 suspects that over zone feeding of traction current is the major cause of the high rail potential. In this paper, a unified chain model of DC traction power system is proposed to simulate the distribution of rail potential and stray current. Field tests and simulations have been carried out to study whether over zone feeding has an impact on rail potential and stray current. Results show that over zone feeding widely exists in DC traction power system and that the rail potential and stray current can be reduced effectively by preventing the over zone feeding of traction current.

  8. The COSMO coronagraph optical design and stray light analysis

    Science.gov (United States)

    Gallagher, Dennis; Wu, Zhen; Larson, Brandon; Nelson, Peter G.; Oakley, Phil; Sewell, Scott; Tomczyk, Steven

    2016-07-01

    The Coronal Solar Magnetism Observatory Large Coronagraph (COSMO-LC) is a 1.5 meter Lyot coronagraph dedicated to measuring magnetic fields and plasma properties in the solar corona. The COSMO-LC will be able to observe coronal emissions lines from 530-1100 nm using a filtergraph instrument. COSMO-LC will have a 1 degree field of view to observe the full solar corona out to 1 solar radius beyond the limb of the sun. This presented challenges due to the large Etendue of the system. The COSMO-LC spatial resolution is 2 arc-seconds per pixel (4k X 4k). The most critical part of the coronagraph is the objective lens that is exposed to direct sunlight that is five orders of magnitude brighter than the corona. Therefore, it is key to the operation of a coronagraph that the objective lens (O1) scatter as little light as possible, on order a few parts per million. The selection of the material and the polish applied to the O1 are critical in reducing scattered light. In this paper we discuss the design of the COSMO-LC and the detailed design of the O1 and other key parts of the COSMO-LC that keep stray light to a minimum. The result is an instrument with stray light below 5 millionths the brightness of the sun 50 arc-seconds from the sun. The COSMO-LC has just had a Preliminary Design Review (PDR) and the PDR design is presented.

  9. Prevalence of intestinal protozoan parasites in stray and domicile ...

    African Journals Online (AJOL)

    admin

    We examined using standard method 108 stool specimens of stray and domicile dogs collected ... (P<0.001) while the stray dogs had more intestinal parasitic infection (68.3%) than ... low power magnification to detect the oocysts and the oil immersion objective to identify them. The complete surface of the smear was.

  10. Stray light correction of array spectroradiometers for solar UV measurements.

    Science.gov (United States)

    Nevas, Saulius; Gröbner, Julian; Egli, Luca; Blumthaler, Mario

    2014-07-01

    An approach is presented to characterize and correct stray light in spectra measured with array spectroradiometers and caused by out-of-spectral range radiation. A prerequisite for out-of-range stray light correction is knowledge of the spectral irradiance not measured by the instrument itself. A way of solving this problem for solar UV measurements is shown. The effect of out-of-range stray light is especially important for solar UV spectroradiometers typically having a spectral range narrower than that of the silicon detectors in use. Two different types of instruments used for solar UV measurements were characterized and corrected for out-of-range and in-range stray light. As a hardware solution to the out-of-range stray light problem, a bandpass filter was fitted in one array spectroradiometer. Results of test measurements using this modified instrument are also shown.

  11. Simulation of stray grain formation at the platform during Ni-base single crystal superalloy DD403 casting

    Directory of Open Access Journals (Sweden)

    Si-feng Gao

    2015-03-01

    Full Text Available The mechanism of stray grain formation at the platform of turbine blade simulator and the effect of withdrawal rate (V on the stray grain phenomenon have been investigated using a macro-scale ProCAST coupled with a 3D Cellular Automaton Finite Element (CAFE model. The results indicate that the stray grains nucleate at the edges of platform at V =150 μm·s-1 and 200 μm·s-1. Using ProCAST computer simulation software, it was proven that the stray grain formation is significantly dependent on the undercooling and the temperature field distribution in the platform. The macroscopic curvature of the liquidus isotherm becomes markedly concave with an increase in the withdrawal rate. The probability of stray grain formation at the edges of platform can be increased by increasing the withdrawal rate in the range of 70 μm·s-1 to 200 μm·s-1.

  12. Study of Liquid Sheet Emanating from a Simplex Fuel Nozzle*

    Science.gov (United States)

    Jog, M. A.; Jeng, S. M.; Dimicco, R.; Oplaski, A.; Holtzclaw, D.; Benjamin, M.

    1996-11-01

    We have computationally modeled the flow in a simplex nozzle and have predicted the characteristics of the liquid sheet emanating from it. Simplex nozzles are commonly used for fuel injection in gas turbine engines. The Arbitrary Lagrangian-Eulerian numerical method is used with a finite volume formulation to solve the governing equations. The free-surface positions are tracked Lagrangianly, thereby avoiding any numerical smearing at the interface. An adaptive grid generation technique is used to body-fit the interior grids to the free surface. The thickness and the angle of the liquid sheet emanating from the nozzle have been predicted. As the commonly used simplex fuel nozzles are small, it is difficult to make accurate measurements on the fluid flow properties within the body of the nozzle and near the nozzle exit. To overcome these difficulties, a large-scale transparent prototype nozzle is used to provide adequate spatial resolution for observation. An argon laser is used for measurements of the liquid sheet thickness. The liquid surface positions as a function of time are recorded using a high speed camera. Comparison of our computational results with the experimental measurements show excellent agreement. *Work supported by Ohio Aerospace Institute and Parker Hannifin Co.

  13. Augustin Emane, Docteur Schweitzer, une icône africaine

    OpenAIRE

    Ceriana Mayneri, Andrea

    2017-01-01

    Augustin Emane a écrit un livre important sur la manière dont la figure d’Albert Schweitzer continue d’être remémorée au Gabon un demi-siècle après sa mort. Pour l’exceptionnalité de son travail de médecin en Afrique, puis pour son engagement contre la course aux armes atomiques (en 1952 il fut lauréat du prix Nobel pour la paix), Schweitzer a été un personnage célèbre, une figure publique influente de la première moitié du XXe siècle en Europe et en Occident. Sa trajectoire professionnelle e...

  14. Stray light correction for solar measurements using array spectrometers.

    Science.gov (United States)

    Kreuter, Axel; Blumthaler, Mario

    2009-09-01

    A stray light matrix correction method for array spectrometers is presented that is specifically tailored for solar spectral measurements. A stray light distribution function based on a single laser line measurement is approximated by an analytical function using three parameters only. This function is the basis for the stray light correction matrix. One cutoff filter is then used to adjust an offset parameter such that stray light corrected data are spectrally flat and around zero below the cutoff wavelength. This parameter also accounts for the IR contribution and has to be adjusted individually for each type of spectrum. A solid validation is given by intercomparison of calibrated solar spectra with a double-monochromator spectroradiometer. An agreement of 5% for wavelengths down to 307 nm and solar zenith angle smaller than 70 degrees is achieved.

  15. Conformal Carbon Nanotubes for Stray Light Suppression Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Our objective is to apply CVD and non-CVD carbon nanotubes to complex shapes that numerous scientists have requested for stray light control.  Currently, CVD...

  16. Prevalence of parasitic infections of stray cats in Jammu, India

    African Journals Online (AJOL)

    ADEYEYE

    Stray cats are afflicted with various parasitic infestations and the infective stages of these parasites may spread infection to other .... Plate V: Photomicrograph of isospora isolated from faecal sample of .... of Intestinal parasites in dogs and cats.

  17. Stray voltage and robotic milking of dairy cows

    Energy Technology Data Exchange (ETDEWEB)

    Rodenburg, J.; Lang, B. [Ontario Ministry of Agriculture (Canada)

    2009-12-15

    Stray voltage in livestock agriculture is the difference in voltage potential measured between two surfaces that may be contacted simultaneously by an animal. The reactions of animals to mild electric shocks caused by stray voltage have been reported to include behavioural changes, changes in milking characteristics of dairy cows and changes in production performance. It can make cows more reluctant to enter the farm dairy and can induce more frequent dunging and urination in the holding yards or during milking. Milk production may be reduced if avoidance behaviours are severe. This factsheet outlines appropriate testing of a robot site for stray voltage. Correction and prevention options available to reduce or eliminate stray voltage in robotic milking systems, i.e. equipotential plane or slatted floors, are discussed along with advantages and disadvantages of each. The most appropriate solution may depend on the voltage level found, the utility's policies and whether it is new construction or renovation.

  18. Stray light and its reduction of focal plane arrays

    Science.gov (United States)

    Yu, Chen-hui; Zhou, Jian-kang; Shi, Rong-bao; Shen, Wei-ming

    2011-08-01

    Existing studies have paid much attention to stray light of lenses. However, the ghost reflection inside FPA (Focal Plane Array) detector is almost ignored which is, in fact, also an unnegligible source of stray light in digital imaging systems. Ghosting between window surfaces and CCD photosensitive area is often a major source of stray light in FPA detectors, it may lead to image blur, color distortion, and contrast reduction. Besides, diffraction pattern can be observed from front-illuminated CCD as the incident beam can be diffracted by its polysilicon electrode gates at the surface. In this paper, we study the generation mechanism and the reduction approaches to such stray light. Both front-illuminated and back-illuminated CCDs (Charge Coupled Device) are investigated in our study. We build models to identify stray light paths and predict window ghost image characteristics. Furthermore, three methods, i.e., anti-reflective coating method, fluid-filled method and deconvolution method are presented to decrease the stray light. The first anti-reflective coating method can be effectively used in back-thinned CCDs to reduce the reflection and to maximize quantum efficiency. The second fluid-filled method attempts to reduce the effects of unwanted light contamination by simulating some characteristics of the human eyes. The use of liquid can reduce the fresnel reflectance of interface. In addition, the acquired images contaminated by FPA's stray light are post-processed with the deconvolution method. Effectiveness of our proposed methods is verified with experiments. It is shown that stray light of FPA can be efficiently reduced.

  19. Simple spectral stray light correction method for array spectroradiometers

    Science.gov (United States)

    Zong, Yuqin; Brown, Steven W.; Johnson, B. Carol; Lykke, Keith R.; Ohno, Yoshi

    2006-02-01

    A simple, practical method has been developed to correct a spectroradiometer's response for measurement errors arising from the instrument's spectral stray light. By characterizing the instrument's response to a set of monochromatic laser sources that cover the instrument's spectral range, one obtains a spectral stray light signal distribution matrix that quantifies the magnitude of the spectral stray light signal within the instrument. By use of these data, a spectral stray light correction matrix is derived and the instrument's response can be corrected with a simple matrix multiplication. The method has been implemented and validated with a commercial CCD-array spectrograph. Spectral stray light errors after the correction was applied were reduced by 1-2 orders of magnitude to a level of approximately 10-5 for a broadband source measurement, equivalent to less than one count of the 15-bit-resolution instrument. This method is fast enough to be integrated into an instrument's software to perform real-time corrections with minimal effect on acquisition speed. Using instruments that have been corrected for spectral stray light, we expect significant reductions in overall measurement uncertainties in many applications in which spectrometers are commonly used, including radiometry, colorimetry, photometry, and biotechnology.

  20. Photoperiodic Effects on the Emanation of Volatiles from Alfalfa (Medicago sativa L.) Florets 1

    Science.gov (United States)

    Loper, G. M.; Lapioli, A. M.

    1972-01-01

    Alfalfa (Medicago sativa L.) plants acclimated to photoperiods of 18 hours light, 6 hour dark in plant growth chambers exhibited a daily cyclic pattern of floret volatile emanation with a maximum emanation of about 6.5 nanograms of hydrocarbons/floret·30 minutes. This maximum was reached about 6 to 8 hours into the light period. After 8 hours of light, emanation of volatiles decreased rapidly to less than 0.1 ng/floret·30 min even though light and temperature remained constant. Under continuous illumination, only a small increase of volatile emanation occurred during the following 24 hours. It appeared that a dark period was necessary to promote floret volatile emanation. Floret volatile emanation was drastically affected for at least 7 days following a photoperiod change. A photoperiod change caused 6-fold concentration oscillations every 2 hours. The results are interpreted on the basis of a very active floral metabolism controlled by photoperiodically induced rhythms. PMID:16658038

  1. Prevalence of external ear disorders in Belgian stray cats.

    Science.gov (United States)

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

    2017-04-01

    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.

  2. 48 CFR 239.7102-2 - Compromising emanations-TEMPEST or other standard.

    Science.gov (United States)

    2010-10-01

    ... INFORMATION TECHNOLOGY Security and Privacy for Computer Systems 239.7102-2 Compromising emanations—TEMPEST or other standard. For acquisitions requiring information assurance against compromising emanations, the...

  3. Measurement of stray neutron doses inside the treatment room from a proton pencil beam scanning system.

    Science.gov (United States)

    Mojżeszek, N; Farah, J; Kłodowska, M; Ploc, O; Stolarczyk, L; Waligórski, M P R; Olko, P

    2017-02-01

    To measure the environmental doses from stray neutrons in the vicinity of a solid slab phantom as a function of beam energy, field size and modulation width, using the proton pencil beam scanning (PBS) technique. Measurements were carried out using two extended range WENDI-II rem-counters and three tissue equivalent proportional counters. Detectors were suitably placed at different distances around the RW3 slab phantom. Beam irradiation parameters were varied to cover the clinical ranges of proton beam energies (100-220MeV), field sizes ((2×2)-(20×20)cm(2)) and modulation widths (0-15cm). For pristine proton peak irradiations, large variations of neutron H(∗)(10)/D were observed with changes in beam energy and field size, while these were less dependent on modulation widths. H(∗)(10)/D for pristine proton pencil beams varied between 0.04μSvGy(-1) at beam energy 100MeV and a (2×2)cm(2) field at 2.25m distance and 90° angle with respect to the beam axis, and 72.3μSvGy(-1) at beam energy 200MeV and a (20×20) cm(2) field at 1m distance along the beam axis. The obtained results will be useful in benchmarking Monte Carlo calculations of proton radiotherapy in PBS mode and in estimating the exposure to stray radiation of the patient. Such estimates may be facilitated by the obtained best-fitted simple analytical formulae relating the stray neutron doses at points of interest with beam irradiation parameters. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  4. Performance of the proposed stray light correction algorithm for the Thermal Infrared Sensor (TIRS) onboard Landsat 8

    Science.gov (United States)

    Montanaro, Matthew; Gerace, Aaron

    2016-09-01

    Imagery from the Landsat 8 Thermal Infrared Sensor (TIRS) have exhibited scene-dependent non-uniform banding and absolute calibration artifacts since the instrument began operation in 2013. These artifacts have been attributed to a stray light effect in which radiance from outside the nominal field-of-view of the instrument enters the optical system and adds a non-uniform signal to the focal plane detectors. A major effort was launched to characterize the stray light sources and derive an operational software correction that could easily be applied to the ground processing system. The proposed solution relies on a regression analysis in which TIRS scene imagery is used in combination with a detailed optical model to calculate the extra stray light signal on the detectors. The predicted signal is then subtracted from the scene data to remove the stray light artifacts. The resulting imagery from the correction algorithm displays a vast improvement in both banding and absolute error over the current TIRS product. The algorithm has the added benefit of being able to run in 'real time' with no additional data needed. Comparisons to MODIS thermal imagery have demonstrated high performance for scenes all over the world and over different material types and temperatures. A summary of these validation studies will be discussed here.

  5. 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...

  6. Stray dog meat consumption and rabies | Wiwanitkit | African Health ...

    African Journals Online (AJOL)

    Journal Home > Vol 14, No 3 (2014) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. 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 ...

  7. Prevalence of intestinal protozoan parasites in stray and domicile ...

    African Journals Online (AJOL)

    Uncontrolled population of stray and domicile dogs with intestinal protozoan in close proximity to increasing densities of human population in urban environments is a common fact in developing countries, in conjunction with the lack of veterinary attention and zoonotic awareness, increases the risks of disease transmission.

  8. Prevalence of parasitic infections of stray cats in Jammu, India

    African Journals Online (AJOL)

    ADEYEYE

    Abstract. Stray cats are afflicted with various parasitic infestations and the infective stages of these parasites may spread infection to other animals including human beings. The study was conducted for a period of one year from March. 2009 to February 2010 to determine the prevalence of parasitic infection in and around ...

  9. Prevalence of parasitic infections of stray cats in Jammu, India ...

    African Journals Online (AJOL)

    Stray cats are afflicted with various parasitic infestations and the infective stages of these parasites may spread infection to other animals including human beings. The study was conducted for a period of one year from March 2009 to February 2010 to determine the prevalence of parasitic infection in and around ...

  10. Hematology and serum chemistry reference values of stray dogs in ...

    African Journals Online (AJOL)

    Hematology and serum chemistry values were obtained from 28 male and 22 female stray dogs in Chittagong Metropolitan area, Bangladesh. The goal of the study was to establish reference value for hematology and serum chemistry for these semi wild animals in relation to age, sex, reproductive stage and body condition.

  11. 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.

  12. An evaluation of safety guidelines to restrict exposure to stray radiofrequency radiation from short-wave diathermy units

    Science.gov (United States)

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

    2004-07-01

    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.

  13. Stray voltage and milk quality: a review.

    Science.gov (United States)

    Reinemann, Douglas J

    2012-07-01

    46 research trials on groups of cows exposed to know levels of voltage and/or current. Many of these were part of the same experiment but exposed cows at different levels of voltage or current. None of these trials or experiments (some using aggressive exposure of cows to mastitis organisms) showed a significant effect of voltage/current exposure on SCC or the incidence of mastitis. Many of these studies showed behavioral modification and some showed minor changes in milk yield, milk composition, or stress hormones (especially cortisol). These studies have shown that increased concentrations of the stress hormone cortisol do not occur at levels below behavioral response levels and only become apparent in some, but not all, cows at substantially higher voltage/current exposures than the threshold required for behavioral modification. This body of research indicates that while exposure to stray voltage at levels of 2 V to 4 V may be a mild stressor to dairy cows, it does not contribute to increased SCC or incidence of mastitis or reduced milk yield.

  14. The human volatilome: volatile organic compounds (VOCs) in exhaled breath, skin emanations, urine, feces and saliva.

    Science.gov (United States)

    Amann, Anton; Costello, Ben de Lacy; Miekisch, Wolfram; Schubert, Jochen; Buszewski, Bogusław; Pleil, Joachim; Ratcliffe, Norman; Risby, Terence

    2014-09-01

    Breath analysis is a young field of research with its roots in antiquity. Antoine Lavoisier discovered carbon dioxide in exhaled breath during the period 1777-1783, Wilhelm (Vilém) Petters discovered acetone in breath in 1857 and Johannes Müller reported the first quantitative measurements of acetone in 1898. A recent review reported 1765 volatile compounds appearing in exhaled breath, skin emanations, urine, saliva, human breast milk, blood and feces. For a large number of compounds, real-time analysis of exhaled breath or skin emanations has been performed, e.g., during exertion of effort on a stationary bicycle or during sleep. Volatile compounds in exhaled breath, which record historical exposure, are called the 'exposome'. Changes in biogenic volatile organic compound concentrations can be used to mirror metabolic or (patho)physiological processes in the whole body or blood concentrations of drugs (e.g. propofol) in clinical settings-even during artificial ventilation or during surgery. Also compounds released by bacterial strains like Pseudomonas aeruginosa or Streptococcus pneumonia could be very interesting. Methyl methacrylate (CAS 80-62-6), for example, was observed in the headspace of Streptococcus pneumonia in concentrations up to 1420 ppb. Fecal volatiles have been implicated in differentiating certain infectious bowel diseases such as Clostridium difficile, Campylobacter, Salmonella and Cholera. They have also been used to differentiate other non-infectious conditions such as irritable bowel syndrome and inflammatory bowel disease. In addition, alterations in urine volatiles have been used to detect urinary tract infections, bladder, prostate and other cancers. Peroxidation of lipids and other biomolecules by reactive oxygen species produce volatile compounds like ethane and 1-pentane. Noninvasive detection and therapeutic monitoring of oxidative stress would be highly desirable in autoimmunological, neurological, inflammatory diseases and cancer

  15. EPA Method 903.1: Radium-226 in Drinking Water Radon Emanation Technique

    Science.gov (United States)

    SAM lists this method to provide for the analysis of drinking water samples that contain Radium-226, and is based on the emanation and scintillation counting of Radon-222, the immediate decay product of Radium-226.

  16. Radon Emanation from NORM-Contaminated Pipe Scale, Soil, and Sediment at Petroleum Industry Sites

    Energy Technology Data Exchange (ETDEWEB)

    Rood, A.S.; White, G.J.

    1999-10-07

    This report describes a study of radon (Rn) emanation from pipe scale and soil samples contaminated with naturally occurring radioactive material (NORM). Samples were collected at petroleum production sites in Oklahoma, Michigan, Kentucky, and Illinois. For comparison, data are also presented from preliminary studies conducted at sites in Texas and Wyoming. All samples collected were analyzed for their Rn emanation fraction, defined as the fraction of 222Rn produced that enters the interconnected pore space within a medium contaminated with 226Ra before the 222Rn undergoes radioactive decay. This measure represents one of the important parameters that determine the overall Rn activity flux from any solid medium. The goal of this project was to determine whether Rn emanation from pipe scale and soil is similar to emanation from uranium mill tailings.

  17. Development of an Insect Repellent Based on Human Skin Emanations. Phase 1

    Science.gov (United States)

    1996-10-01

    March 1963, pp 250-255. 22. Price, G.D., N. Smith and D.A. Carlson. The attraction of female mosquitoes ( Anopheles quadrimaculatus SAY) to stored human...emanations in a dual port olfactometer. Mosquitoes (female Anopheles quadrimaculatus SAY) were preferentially attracted to the "emanation" air, even though...female Aedes aegypti and Anopheles quadrimaculatus Say mosquitoes. This residue was characterized as volatile, and stable on refrigerated storage for up

  18. Beta Factors for Collinear Asymmetrical Cracks Emanating from an Offset Circular Hole in a Rectangular Plate

    Science.gov (United States)

    2016-05-01

    closed-form analytical two-dimensional Beta factor solution for the related case of symmetrical cracks emanating from a central hole in a finite-width...closed-form analytical two-dimensional Beta factor solution that is applicable to symmetrical cracks emanating from a central hole in a finite-width...import the tables into a spreadsheet , such as Microsoft Excel, when using spaces as the data delimiter. Table 1 to Table 36 present the Beta

  19. ASSESMENT OF INFORMARTION SECURITY METHOD FROM OUTFLOW THROUGH TRANSIENT ELECTROMAGNETIC PULSE EMANATION

    OpenAIRE

    Хлапонін, Ю.І.

    2016-01-01

    Recently, methods of information interception with transient electromagnetic pulse emanation of local network elements are getting developed. Separate computers security methods are worked out well and backed up with necessary regulatory documents. However, information security through TEMPEST is far more hard to do in local network then in separate devices. That’s why special institutional, algorithmic and methodological approaches should be used to detect electromagnetic pulse emanations. M...

  20. Fast space-varying convolution and its application in stray light reduction

    Science.gov (United States)

    Wei, Jianing; Cao, Guangzhi; Bouman, Charles A.; Allebach, Jan P.

    2009-02-01

    Space-varying convolution often arises in the modeling or restoration of images captured by optical imaging systems. For example, in applications such as microscopy or photography the distortions introduced by lenses typically vary across the field of view, so accurate restoration also requires the use of space-varying convolution. While space-invariant convolution can be efficiently implemented with the Fast Fourier Transform (FFT), space-varying convolution requires direct implementation of the convolution operation, which can be very computationally expensive when the convolution kernel is large. In this paper, we develop a general approach to the efficient implementation of space-varying convolution through the use of matrix source coding techniques. This method can dramatically reduce computation by approximately factoring the dense space-varying convolution operator into a product of sparse transforms. This approach leads to a tradeoff between the accuracy and speed of the operation that is closely related to the distortion-rate tradeoff that is commonly made in lossy source coding. We apply our method to the problem of stray light reduction for digital photographs, where convolution with a spatially varying stray light point spread function is required. The experimental results show that our algorithm can achieve a dramatic reduction in computation while achieving high accuracy.

  1. Seroprevalence of Ehrlichia canis infection in stray dogs from Serbia

    Directory of Open Access Journals (Sweden)

    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.

  2. Reliability of the compensation comparison stray-light measurement method.

    Science.gov (United States)

    Coppens, Joris E; Franssen, Luuk; van Rijn, L J; van den Berg, Thomas J T P

    2006-01-01

    The compensation comparison (CC) method is a psychophysical technique to measure retinal stray light. It uses a two alternative forced choice (2AFC) measurement paradigm. The 25 binary (0 and 1) responses resulting from the 2AFC test are analyzed using maximum likelihood estimates. The likelihood function is used to give two quantities: the most likely stray-light level of the eye under investigation, and the accuracy of this estimate [called expected standard deviation (ESD)]. The CC method is used in 2422 subjects of the GLARE study. Each eye is tested twice to allow analysis of measurement repeatability. Furthermore, the large amount of responses is used to evaluate the shape of the psychometric function, for which a mathematical model is used. The shape of the psychometric function found by averaging the 0 and 1 responses fit well to the model function. Data sorted according to ESD show differences in the shape of the psychometric function between good and bad observers. These different shapes for the psychometric function are used to reanalyze the data, but the stray-light results remain virtually identical. ESD proves to be an efficient tool to detect unreliable measurements. In clinical practice, ESD may be used to decide whether to repeat a measurement.

  3. Study of radon emanation from uranium mill tailings. Relations between radon emanating power and physicochemical properties of the material; Etude de l'emanation du radon a partir de residus de traitement de minerais d'uranium. Mise en evidence de relations entre le facteur d'emanation et les caracteristiques du materiau

    Energy Technology Data Exchange (ETDEWEB)

    Pellegrini, D

    1999-07-01

    The uranium extraction from ores leads to large amounts of mill tailings still containing radionuclides, such as thorium-230 and radium-226, which generate radon-222. Without protective action, radon exposition may be high enough to cause concern for health of populations living in the vicinity of an uranium mill tailings disposal. This exposition pathway has therefore to be taken into account in the radiological impact studies. The emanating power, i.e. the part of radon atoms which escape from the solid particles, is directly involved in the radon source term evaluation. It may be determined for a given material by laboratory measurements. Emanating powers from 0.08 to 0.33 have been obtained for mill tailings from Jouac (Limousin, France), at various moisture contents. In order to reduce the relations of dependence between some of the emanation parameters, more simple phases, kaolinite and polymeric resins, have been studied. Those experiments have led us to the selection of the mechanisms and the parameters to consider for the development of an emanation modelling. The whole of the results obtained point out the radon sorption, in various proportions depending on the materials. The moisture content influence on the emanation from materials containing fine particles have been confirmed: the emanation increases with this parameter until a continuous water film surrounding the particles have been formed, and then become constant. This 'water effect' occurs in a moisture content range, which depends on the material porosity. Elsewhere, the presence of amorphous phases may led to a high radon emanation. (author)

  4. Identification and mitigation of stray laser light in the Thomson scattering system on the Madison Symmetric Torus (MST).

    Science.gov (United States)

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

    2016-11-01

    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.

  5. 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.

  6. Identification and mitigation of stray laser light in the Thomson scattering system on the Madison Symmetric Torus (MST)

    Science.gov (United States)

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

    2016-11-01

    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.

  7. Green's function solution and applications for cracks emanating from a circular hole in an infinite sheet

    Science.gov (United States)

    Shivakumar, V.; Forman, R. G.; Rosencranz, R., Jr.

    1983-01-01

    Stress-intensity factors are obtained for point loaded equal length cracks emanating from a circular hole in an infinite plate. A series approach and the Muskhelishvili formulation in the two-dimensional theory of elasticity are used to derive the solution. The applicability of the solution is demonstrated by using it as a Green's function to obtain stress-intensity factors in the case of (1) biaxial tension and pure shear of an infinite plate and (2) tension and pin loading of a plate with cracks emanating from one hole in a row of holes.

  8. Long-term flow monitoring of submarine gas emanations

    Science.gov (United States)

    Spickenbom, K.; Faber, E.; Poggenburg, J.; Seeger, C.

    2009-04-01

    consists of gas collector, sensor head and pressure housing for electronics and power supply. The collector is a plastic funnel, enclosed in a stainless-steel frame to add weight and stability. The whole unit is fixed to the sediment by nails or sediment screws. The sensor head is equipped with an "inverted tipping-bucket" sensor, which basically works like a turned upside-down rain gauge. It fills with the collected gas until full, then empties completely and starts again, which allows the calculation of the flow rate by container volume and frequency of the cycle. This sensor type is very robust due to a design nearly without moving parts and suitable for very low to medium flow rates. For higher flow rates different sensor heads using turbine wheels or pressure differences can be used. The pressure housing for this prototype is made of aluminium and contains a Hobo Pendant data logger with integrated battery supply. Since this setup is inexpensive, it can be deployed in numbers to cover larger areas. By addition of multi-channel data loggers, data transmission by acoustic modem or cable, relay stations on the seafloor or buoys etc. the infrastructure can be adapted to the environmental setting and financial budget. Prototype tests under laboratory conditions as well as field tests on natural submarine gas vents as an analogue to leaking storage sites have demonstrated the capabilities and robustness of the systems.

  9. Vector-Borne Pathogens in Stray Dogs in Northeastern Turkey.

    Science.gov (United States)

    Guven, Esin; Avcioglu, Hamza; Cengiz, Seyda; Hayirli, Armagan

    2017-08-01

    This experiment was carried out to attain prevalence and molecular characterization of pathogens causing canine vector-borne diseases (CVBDs) including babesiosis, hepatozoonosis, leishmaniasis, filariosis (Dirofilaria immitis, Dirofilaria repens, and Acanthocheilonema reconditum), ehrlichiosis (Ehrlichia canis), and anaplasmosis (Anaplasma platys) in stray dogs. The study material consisted of 133 asymptomatic female (n = 96) and male (n = 37) stray dogs (≤1 year old, n = 16 and 1-6 years old, n = 117) housed in the Animal Care and Rehabilitation Center, Erzurum, Northeastern Turkey. Conventional and nested PCR were performed on blood samples to detect Babesia spp., Leishmania spp., Hepatozoon spp., D. immitis, D. repens, A. reconditum, E. canis, and A. platys. Sex and age association with the pathogen prevalence was determined using X 2 statistics. The positivity rate for at least one CVBD pathogen was 48.9% (65/133). DNA of B. canis, Hepatozoon spp., H. canis, D. immitis, and E. canis were detected in 5.3% (7/133), 27.1% (36/133), 5.3% (7/133), 1.5% (2/133), and 9.8% (13/133) of the dogs, respectively. Leishmania spp., D. repens, A. reconditum, and A. platys DNA were not detected. Mixed pathogens were determined in seven (10.8%) of the infected dogs, with predominant involvement of Hepatozoon spp. or H. canis. The pathogen prevalence did not vary by sex or age. Nucleotide blast analysis of Erzurum isolates showed 99.8-100% identities with the corresponding reference isolates. This study indicates presence of five CVB pathogens, including the first report of E. canis, in stray dogs in Erzurum, Turkey.

  10. Physical Parameters Affecting the Emanation of RADON-222 from Coal Ash.

    Science.gov (United States)

    Barton, Terence Patrick

    The Rn-222 emanation coefficients for coal ash and parameters which affected them were measured. Samples of ash from both stoker fired and pulverized coal fired boilers were obtained. The stoker ash samples were mechanically separated into size fractions. The pulverized samples were too fine for mechanical sizing and were categorized qualitatively according to origin. Bulk density of the stoker fractions was measured and ranged from .488 to .944 g-cm('-3), increasing as a function of decreasing particle size. Bulk density of the pulverized ash ranged from 1.254 to 1.520 g-cm('-3). Specific gravity of the stoker fractions ranged from 2.017 to 2.390 g-cm('-3), also increasing as a function of decreasing particle size. Specific gravity of the pulverized ash ranged from 2.357 to 2.588 g-cm(' -3). Ra-226 content of the samples was determined by gamma spectrometric analysis of the 352-KeV gamma of Pb -214 and the 609-KeV gamma of Bi-214 from sealed samples of ash. Ra-226 concentrations in the stoker fractions ranged from 11.82 to 16.77 dpm-g('-1), increasing as a function of decreasing particle size. Ra-226 concentrations in the pulverized ash ranged from 6.44 to 7.59 dpm-g(' -1). Scintillation cells were constructed out of commonly available materials and a commercial preparation of ZnS(Ag) scintillator. Emanation chambers which allowed for moderately large sample masses were constructed. The procedure used to measure emanation coefficients was shown to be insensitive to ingrowth time at greater than 3 days ingrowth and relatively insensitive to variations in sample porosity. Emanation coefficients of the stoker fractions were measured at moisture contents of 0, 1.0, 10, 20, and 40 percent by weight. Within each size fraction the emanation coefficient increased as a function of moisture content, ranging from 9.58 x 10('-4) to 4.13 x 10('-2) between 0 and 20 percent moisture, respectively. Emanation coefficients also increased as a function of decreasing particle size

  11. EVALUATION OF RADON EMANATION FROM SOIL WITH VARYING MOISTURE CONTENT IN A SOIL CHAMBER

    Science.gov (United States)

    The paper describes measurements to quantitatively identify the extent to which moisture affects radon emanation and diffusive transport components of a sandy soil radon concentration gradient obtained in the EPA test chamber. The chamber (2X2X4 m long) was constructed to study t...

  12. Electric Field Imaging Project

    Science.gov (United States)

    Wilcutt, Terrence; Hughitt, Brian; Burke, Eric; Generazio, Edward

    2016-01-01

    NDE historically has focused technology development in propagating wave phenomena with little attention to the field of electrostatics and emanating electric fields. This work is intended to bring electrostatic imaging to the forefront of new inspection technologies, and new technologies in general. The specific goals are to specify the electric potential and electric field including the electric field spatial components emanating from, to, and throughout volumes containing objects or in free space.

  13. 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.

  14. Hemotropic Mycoplasmas in Stray Cats in Kerman, Iran

    Directory of Open Access Journals (Sweden)

    Samira Hosseini Hooshyar

    2016-09-01

    Full Text Available Background:     Feline haemotropic mycoplasma are a group of pleomorphic bacteria causing hemolytic anemia along with anorexia, lethargy, dehydration, weight loss and in many cases sudden death in infected animal. However, there is a limited data on the prevalence of these organisms in Iranian cats. Methods:    We investigated the presence of feline haemotropic mycoplasma and probable risk factors for these infections among 60 ectoparasite-infested stray cats in southeast of Iran using PCR assay. Results:     The overall prevalence of haemotropic mycoplasma was estimated 18.3%. Pallor mucous membrane, anorexia, weight loss and splenomegaly were the most common signs and the infection rate was significantly higher in symptomatic cats in comparison with apparently healthy ones (P = 0.001. Age, gender and hematological alterations were not significantly associated with infection status while the level of BUN, creatinine, total protein and globulin were significantly higher among infected animals.Conclusion:    The prevalence of feline hemoplasma infection in stray cats seems to be considerable in our study. More investigations are needed to obtain further information on epidemiological aspects of hemoplasmas in cats in Iran.

  15. Hemotropic Mycoplasmas in Stray Cats in Kerman, Iran

    Directory of Open Access Journals (Sweden)

    Samira Hosseini Hooshyar

    2017-01-01

    Full Text Available Background:     Feline haemotropic mycoplasma are a group of pleomorphic bacteria causing hemolytic anemia along with anorexia, lethargy, dehydration, weight loss and in many cases sudden death in infected animal. However, there is a limited data on the prevalence of these organisms in Iranian cats. Methods:    We investigated the presence of feline haemotropic mycoplasma and probable risk factors for these infections among 60 ectoparasite-infested stray cats in southeast of Iran using PCR assay. Results:     The overall prevalence of haemotropic mycoplasma was estimated 18.3%. Pallor mucous membrane, anorexia, weight loss and splenomegaly were the most common signs and the infection rate was significantly higher in symptomatic cats in comparison with apparently healthy ones (P = 0.001. Age, gender and hematological alterations were not significantly associated with infection status while the level of BUN, creatinine, total protein and globulin were significantly higher among infected animals.Conclusion:    The prevalence of feline hemoplasma infection in stray cats seems to be considerable in our study. More investigations are needed to obtain further information on epidemiological aspects of hemoplasmas in cats in Iran.

  16. 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

  17. 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

  18. Electrolytic corrosion of water pipeline system in the remote distance from stray currents—Case study

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    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.

  19. Behavioural and electrophysiological responses of the malaria mosquito Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) to human emanations

    NARCIS (Netherlands)

    Qiu, Y.T.; Smallegange, R.C.; Hoppe, S.; Loon, van J.J.A.; Bakker, E.J.; Takken, W.

    2004-01-01

    Behavioural and electrophysiological responses of Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) to human skin emanations collected on glass beads were studied using a dual-port olfactometer and electroantannography. Glass beads to which skin emanations from human hands had been

  20. Assessment of (222)Rn emanation from ore body and backfill tailings in low-grade underground uranium mine.

    Science.gov (United States)

    Mishra, Devi Prasad; Sahu, Patitapaban; Panigrahi, Durga Charan; Jha, Vivekanand; Patnaik, R Lokeswara

    2014-02-01

    This paper presents a comparative study of (222)Rn emanation from the ore and backfill tailings in an underground uranium mine located at Jaduguda, India. The effects of surface area, porosity, (226)Ra and moisture contents on (222)Rn emanation rate were examined. The study revealed that the bulk porosity of backfill tailings is more than two orders of magnitude than that of the ore. The geometric mean radon emanation rates from the ore body and backfill tailings were found to be 10.01 × 10(-3) and 1.03 Bq m(-2) s(-1), respectively. Significant positive linear correlations between (222)Rn emanation rate and the (226)Ra content of ore and tailings were observed. For normalised (226)Ra content, the (222)Rn emanation rate from tailings was found to be 283 times higher than the ore due to higher bulk porosity and surface area. The relative radon emanation from the tailings with moisture fraction of 0.14 was found to be 2.4 times higher than the oven-dried tailings. The study suggested that the mill tailings used as a backfill material significantly contributes to radon emanation as compared to the ore body itself and the (226)Ra content and bulk porosity are the dominant factors for radon emanation into the mine atmosphere.

  1. High prevalence of hemotropic mycoplasmosis among stray cats in Iran

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    Maryam Rassouli

    2016-03-01

    Full Text Available Objective: To understand the prevalence of the hemotropic mycoplasmosis among stray cats. Methods: In this research, 52 cats (30 queens and 22 toms of different municipal regions of Tehran, the capital of Iran, were restrained and injected with tranquilizer. Peripheral blood samples were taken in order to detect blood parasites and taken blood smears were transferred to the parasitology laboratory, fixed by methanol and stained by Giemsa. Results: About 32.7% of samples were positive for Mycoplasma spp. and some abnormalities were observed in leukocyte numbers. Conclusions: There are some unclear aspects of hemotropic mycoplasmosis in Iran. This disease also has zoonotic importance. Therefore, some further researches are necessary to clarify the importance of the disease in different parts of Iran and its potential vectors.

  2. Prevalence of Toxoplasma gondii antibodies in stray and owned dogs of Grenada, West Indies

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    Ravindra N. Sharma

    2014-09-01

    Full Text Available Aim: This serological survey was undertaken to estimate the prevalence of Toxoplasma gondii in two populations of dogs (stray and owned dogs in Grenada. Dogs get infected with oocysts voided from cats, definitive hosts of T. gondii. In dogs, T. gondii causes subclinical to clinical disease. Earlier studies conducted in Grenada on a small population of owned dogs showed evidence of exposure to T. gondii. Materials and Methods: Antibodies to T. gondii were determined in serum samples from 625 dogs (368 stray and 257 owned dogs from around all six parishes in Grenada, West Indies, using an indirect enzyme linked immunosorbent assay. Results: Antibodies to T. gondii were found in 123 (33.4%; 95% confidence interval [CI]: 28.58-38.22% of stray dogs and in 64 (25%; 95% CI: 19.71-30.29% of the owned dogs. Seropositivity was higher in stray dogs than in pet dogs (p=0.026. Whereas, there was no sex predisposition to seropositivity in owned dogs (p=1.0, female stray dogs showed a higher prevalence than male stray dogs (p=0.04. Conclusion: These results support previous findings that T. gondii is prevalent in Grenada. In this study, overall seropositivity for T. gondii in dogs in Grenada is lower than noted in 2008, but is still higher in stray dogs than in owned dogs.

  3. Stray light analysis for the Thomson scattering diagnostic of the ETE Tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Berni, L. A. [Instituto Nacional de Pesquisas Espaciais (INPE), Laboratorio Associado de Sensores e Materiais (LAS), 12.227-010 Sao Jose dos Campos, SP (Brazil); Albuquerque, B. F. C. [Instituto Nacional de Pesquisas Espaciais (INPE), Engenharia e Tecnologia Espaciais, Divisao de Eletronica Aeroespacial, 12.227-010 Sao Jose dos Campos, SP (Brazil)

    2010-12-15

    Thomson scattering is a well-established diagnostic for measuring local electron temperature and density in fusion plasma, but this technique is particularly difficult to implement due to stray light that can easily mask the scattered signal from plasma. To mitigate this problem in the multipoint Thomson scattering system implemented at the ETE (Experimento Tokamak Esferico) a detailed stray light analysis was performed. The diagnostic system was simulated in ZEMAX software and scattering profiles of the mechanical parts were measured in the laboratory in order to have near realistic results. From simulation, it was possible to identify the main points that contribute to the stray signals and changes in the dump were implemented reducing the stray light signals up to 60 times.

  4. Stray dogs and cats as potential sources of soil contamination with zoonotic parasites

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    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.

  5. Characterization of Himawari-8 AHI 3.9-um channel stray light

    Science.gov (United States)

    Shao, Xi; Wu, Xiangqian; Yu, Fangfang

    2016-09-01

    The Advanced Himawari Imager (AHI) is the primary instrument aboard Himawari-8 and has 16 multispectral channels, including six visible and near infrared and 10 thermal emissive bands. The 3.9-μm channel imagery of AHI has spatial resolution of 2 km and performs routine full-disk imaging every 10 minutes. There have been stray light observed in the full disk imagery of the AHI 3.9-μm channel over a few weeks around February and October-November when the line of sight of the sun is at 10 to 20 degrees south of the nadir of the Himawari-8. In this paper, difference data between consecutive AHI 3.9-μm images have been processed to quantitatively characterize and monitor the AHI stray light. Stray light indices are also developed to trend the occurrence, position and magnitude of the stray light in the AHI 3.9- μm imageries. It is also found that the stray light is the greatest in the AHI 3.9-μm band but also is detectable in other Mid-Wavelength IR channels. Analysis of the ratio of stray light magnitude between AHI 3.9-μm and 6.2-μm band indicates that it is consistent with the ratio of solar radiance for these two bands. This suggests that the stray light is mainly due to direct illumination of the attenuated solar radiation on the AHI detector rather than from onboard thermal body emission due to heating. The upcoming Advanced Baseline Imager (ABI) onboard the GOES-R satellite has very similar spectral and spatial characteristics as AHI. Therefore, characterizing the stray light in the 3.9-μm channel of AHI helps support post-launch calibration activities of ABI.

  6. Genotypic Characterization of Bordetella bronchiseptica Strains Isolated from Stray and Pet Dogs

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    Zafer Sayin1*, Asli Sakmanoglu1, Osman Erganis1, Uckun Sait Ucan1, Hasan Huseyin Hadimli1, Zeki Aras2, Gokcenur Sanioglu2 and Alp Aslan Coskun3

    2016-11-01

    Full Text Available Bordetella bronchiseptica (B. bronchiseptica is the most important pathogen associated with kennel cough in dogs. The presence of B. bronchiseptica in pet dogs and shelter dogs with clinical respiratory disease was investigated in present study. The genetic relatedness among the strains was determined to evaluate the role of stray dogs in spread of B. bronchiseptica to pet dogs by detection of virulence genes such as filamentous hemagglutinin (fha, pertactin (prn and dermonecrotic toxin (dnt. We also performed the random amplified polymorphic DNA (RAPD assay. A total of 96 B. bronchiseptica were isolated from stray and pet dogs. The fha, prn and dnt virulence genes were detected in 86, 83.3 and 61.4% strains, respectively by polymerase chain reaction (PCR techniques. The most common genotype from stray and pet dogs was fha+prn+dnt+ as detected in 37.5% and 11.4% of all the strains, respectively. The RAPD assay showed that 3 different patterns were obtained from 96 B. bronchiseptica strains. Sixty one (63.5% of them were clustered in one main group and then further placed in another 2 sub-groups by RAPD assay. Genetic association was seen between the B. bronchiseptica strains from stray and pet dogs. In conclusion, this study revealed that B. bronchiseptica is present at a higher rate in stray dogs than pet dogs. Stray dogs might have a significant role in the transmission of B. bronchiseptica to pet dogs.

  7. Green's function for a crack emanating from a circular hole in an infinite sheet

    Science.gov (United States)

    Shivakumar, V.; Forman, R. G.

    1980-01-01

    Stress-intensity factors, K/I/ and K/II/, are obtained for a point loaded crack emanating from a circular hole in an infinite plate. A series approach and the Muskhelishvili formulation in the two-dimensional theory of elasticity are used to derive the solution. The applicability of the solution is demonstrated by using it as a Green's function to obtain K/I/ and K/II/ and the case of (1) biaxial tension of an infinite plate and (2) bending of a wide strip.

  8. Pinhole castration technique: an alternative to orchiectomy in stray dogs.

    Science.gov (United States)

    Baba, M A; Fazili, M R; Athar, H; Mir, M S; Moulvi, B A; Khan, I

    2013-02-01

    The study evaluates a pinhole castration technique in male stray dogs. Animals (n=18) were randomly allotted to 2 groups: group I (n=12, pinhole castration) and group II (n=6, sham control). Percutaneous (in situ) spermatic cord ligation was performed under xylazine-ketamine anesthesia in all animals of group I. Scrotal and the testicular dimensions and testicular volume were measured on day 28 followed by bilateral orchiectomy in both the groups. Significantly lower readings were obtained from animals of group I when compared with pre-ligation readings as well as the corresponding readings from group II animals. In ligated animals volume of testicles showed a reduction by 40.57%. Histopathological examination of testicles revealed degeneration and atrophy in Group I animals. On the whole pinhole castration was found effective, minimally invasive, cheap, simple and a quick technique for male dog sterilization with potential for adoption in large-scale animal birth control programs. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Population structure of Bartonella henselae in Algerian urban stray cats.

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    Naouelle Azzag

    Full Text Available Whole blood samples from 211 stray cats from Algiers, Algeria, were cultured to detect the presence of Bartonella species and to evaluate the genetic diversity of B. henselae strains by multiple locus VNTR analysis (MLVA. Bartonella henselae was the only species isolated from 36 (17% of 211 cats. B. henselae genotype I was the predominant genotype (64%. MLVA typing of 259 strains from 30 bacteremic cats revealed 52 different profiles as compared to only 3 profiles using MLST. Of these 52 profiles, 48 (92.3% were identified for the first time. One-third of the cats harbored one MLVA profile only. As there was a correlation between the age of cats and the number of MLVA profiles, we hypothesized that the single profile in these cats was the profile of the initial infecting strain. Two-third of the cats harbored 2 to 6 MLVA profiles simultaneously. The similarity of MLVA profiles obtained from the same cat, neighbor-joining clustering and structure-neighbor clustering indicate that such a diversity likely results from two different mechanisms occurring either independently or simultaneously: independent infections and genetic drift from a primary strain.

  10. Divine Emanation As Cosmic Origin: Ibn Sînâ and His Critics

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    Syamsuddin Arif

    2012-11-01

    Full Text Available The question of cosmic beginning has always attracted considerable attention from serious thinkers past and present. Among many contesting theories that have emerged, that of emanation was appropriated by Muslim philosophers like Ibn Sînâ in order to reconcile the Aristotelian doctrine of the eternity of matter with the teaching of al-Qur’ân on the One Creator-God. According to this theory, the universe, which comprises a multitude of  entities, is generated from a transcendent Being, the One, that is unitary, through the medium of  a hierarchy of  immaterial substances. While the ultimate source is undiminished, the beings which are emanated are progressively less perfect as they are further removed from the first principle. The process is conceived as being atemporal and often compared to the efflux of light from a luminous body, or to water flowing from a spring. This metaphysical theory has enabled Ibn Sînâ to solve the vexed problem: given an eternally existing world and one eternally existing God, how can the two necessarily co-exist without having the perfect, simple unity of God destroyed by contact with the multiplicity of material things? The following essay delineates and evaluates both Ibn Sînâ’s arguments as well as the counter-arguments of  his critics.

  11. Enhanced-Adhesion Multi-Walled Carbon Nanotubes on Titanium Substrates for Stray Light Control

    Science.gov (United States)

    Hagopian, John; Getty, Stephanie; Quijada, Manuel

    2012-01-01

    Carbon nanotubes previously grown on silicon have extremely low reflectance, making them a good candidate for stray light suppression. Silicon, however, is not a good structural material for stray light components such as tubes, stops, and baffles. Titanium is a good structural material and can tolerate the 700 C nanotube growth process. The ability to grow carbon nanotubes on a titanium substrate that are ten times blacker than the current NASA state-of-the-art paints in the visible to near infrared spectra has been achieved. This innovation will allow significant improvement of stray light performance in scientific instruments or any other optical system. This innovation is a refinement of the utilization of multiwalled carbon nano tubes for stray light suppression in spaceflight instruments. The innovation is a process to make the surface darker and improve the adhesion to the substrate, improving robustness for spaceflight use. Bright objects such as clouds or ice scatter light off of instrument structures and components and make it difficult to see dim objects in Earth observations. A darker material to suppress this stray light has multiple benefits to these observations, including enabling scientific observations not currently possible, increasing observational efficiencies in high-contrast scenes, and simplifying instruments and lowering their cost by utilizing fewer stray light components and achieving equivalent performance. The prior art was to use commercially available black paint, which resulted in approximately 4% of the light being reflected (hemispherical reflectance or total integrated scatter, or TIS). Use of multiwalled carbon nanotubes on titanium components such as baffles, entrance aperture, tubes, and stops, can decrease this scattered light by a factor of ten per bounce over the 200-nm to 2,500-nm wavelength range. This can improve system stray light performance by orders of magnitude. The purpose of the innovation is to provide an enhanced

  12. Calculation improvement of no-load stray losses in induction motors with experimental validation

    Directory of Open Access Journals (Sweden)

    Kostić Miloje M.

    2015-01-01

    Full Text Available On the basis of the known fact that all air gap main flux density variations are enclosed by permeance slot harmonics, only one component of stray losses in rotor (stator iron is considered in the new classification, instead of 2 components: rotor (stator pulsation iron losses, and rotor (stator surface iron losses. No-load rotor cage (high-frequency stray losses are usually calculated. No-load stray losses are caused by the existence of space harmonics: the air-gap slot permeance harmonics and the harmonics produced by no-load MMF harmonics. The second result is the proof that the corresponding components of stray losses can be calculated separately for the mentioned kind of harmonics. Determination of the depth of flux penetration and calculations of high frequency iron losses are improved. On the basis of experimental validation, it is proved that the new classification of no-load stray losses and the proposed method for the calculation of the total value is sufficiently accurate.

  13. An assessment on the recycling opportunities of wastes emanating from scrap metal processing in Mauritius.

    Science.gov (United States)

    Mauthoor, Sumayya; Mohee, Romeela; Kowlesser, Prakash

    2014-10-01

    This paper presents an assessment on the wastes namely slag, dust, mill scale and sludge resulting from scrap metal processing. The aim of this study is to demonstrate that there are various ways via which scrap metal processing wastes can be reused or recycled in other applications instead of simply diverting them to the landfill. These wastes are briefly described and an overview on the different areas of applications is presented. Based on the results obtained, the waste generation factor developed was 349.3 kg per ton of steel produced and it was reported that slag represents 72% of the total wastes emanating from the iron and steel industry in Mauritius. Finally the suitability of the different treatment and valorisation options in the context of Mauritius is examined. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Estimation of increased regional income that emanates from economically justified road construction projects

    Directory of Open Access Journals (Sweden)

    W. J. Pienaar

    2005-09-01

    Full Text Available This article identifies the possible development benefits than can emanate from economically justified road construction projects. It shows how the once-off increase in regional income resulting from investment in road construction projects, and the recurring additional regional income resulting from the use of new or improved roads can be estimated. The difference is shown that exists between a cost-benefit analysis (to determine how economically justified a project is and a regional economic income analysis (to estimate the general economic benefits that will be developed by investment in and usage of a road. Procedures are proposed through which the once-off and recurring increases in regional income can be estimated by using multiplier and accelerator analyses respectively. Finally guidelines are supplied on the appropriate usage of input variables in the calculation of the regional income multiplier.

  15. 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.

  16. 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

  17. Progress on the prevention of stray light and diffraction effects on the Thai National Telescope

    Science.gov (United States)

    Buisset, Christophe; Prasit, Apirat; Leckngam, Apichat; Lépine, Thierry; Poshyajinda, Saran; Soonthornthum, Boonrucksar; Irawati, Puji; Richichi, Andrea; Sawangwit, Utane; Dhillon, Vik; Hardy, Liam K.

    2015-09-01

    The 2.4-m Thai National Telescope (TNT) is the main facility of the Thai National Observatory located on the Doi Inthanon, Thailand's highest mountain. The first astronomical images obtained at the TNT suffered from diffraction and stray light problems: bright spikes spread from bright stellar images over few arcminutes in the focal plane, and the images taken during observations in bright moon conditions were contaminated by high levels of stray light. We performed targeted investigations to identify the origin of these problems. In a first time, these investigations consisted of analyzing the irradiance distribution of defocused stellar images and of identifying the contributors. We concluded that these bright spikes around the bright stellar images were due to the chamfer and the wavefront error at the mirror edge. We thus installed an annular mask along the edge of the primary mirror that fully suppressed these spikes and we quantified the improvement by observing the double star Sirius. In a second time, we identified the contributors to the stray light by placing a pinhole camera at the TNT focal plane. Then, we designed a new baffle to improve the stray light rejection. The final design of the baffle comprises 21 diaphragms, is painted with an ordinary black paint and was designed, developed and installed on the TNT in less than 8 months. We assessed the improvement on the performance by measuring the variation of the stray light signal before and after installing the baffle in the telescope structure. These steps significantly improved the image quality and enhanced the rejection of the stray light at the focal plane level. In this paper, we present our investigations, we describe the method used to design the TNT baffle, and we present the improvement in quantitative terms.

  18. 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......) 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...

  19. 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......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...

  20. Partial Stray Inductance Modeling and Measuring of Asymmetrical Parallel Branches on the Bus-Bar of Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Chengfei Geng

    2017-10-01

    Full Text Available In order to increase the power rating of electric vehicles, insulated gate bipolar translator (IGBT modules with multiple power terminals are usually adopted. The transient current sharing of the same polarity power terminals is related to the stray inductance in the branches of the bus-bar. Based on the laminated bus-bar of a three-phase inverter in the electric vehicles that consists of asymmetrical parallel branches, this paper investigates the transient current imbalance sharing caused by the asymmetrical stray inductance in the parallel branches of the bus-bar from the view of energy storing and releasing of stray inductance for the first time. Besides, the partial self-inductance and mutual-inductance model of the parallel branches is set up. Finally, a high-precision partial stray inductance measurement method is proposed, and the accuracy of the partial stray inductance model for asymmetrical parallel branches is verified by experimental tests.

  1. Prevalence of Zoonotic and Other Intestinal Protozoan Parasites in Stray Cats (Felis domesticus of Kerman, South-East of Iran

    Directory of Open Access Journals (Sweden)

    Sakineh BEIGI

    2017-01-01

    Full Text Available Intestinal protozoan parasites constitute a major source of diseases for stray cats and have been recognized as important public health problems in several parts of the world. Considering the potential risk of stray cats for public health, present cross-sectional study was carried out to determine the type and frequency of protozoan parasites by faecal examination. A total of 100 stray cats were examined in Kerman city, Iran, Overall 67 cats (67% were infected with at least one protozoan parasite. The following parasites, with their respective prevalence, were found; Isospora felis 38%, Isospora rivolta 25%, Toxoplasma gondii 16%, Sarcocystis spp. 8%, Cryptosporidium spp. 7%, and Giardia sp. 5%. Based on our data, the sex of stray cats was not significantly associated with the prevalence of gastrointestinal protozoan parasites. The high infection rate of zoonotic intestinal protozoan parasites in stray cats is considered to be critical from the viewpoint of public health importance.We

  2. Discharge of water containing waste emanating from land to the marine environment: a water quality management perspective

    CSIR Research Space (South Africa)

    Oelofse, Suzanna HH

    2004-01-01

    Full Text Available The National Water Act, 1998 (Act 36 of 1998) mandates the Department of Water Affairs and Forestry to manage all water containing waste (wastewater), which emanates from land-based sources and which directly impact on the marine environment...

  3. Comments on Neil Dorans's NCME Career Award Address: The Contestant Perspective on Taking Tests--Emanations from the Statue within

    Science.gov (United States)

    Mislevy, Robert J.

    2012-01-01

    This article presents the author's observations on Neil Dorans's NCME Career Award Address: "The Contestant Perspective on Taking Tests: Emanations from the Statue within." He calls attention to some points that Dr. Dorans made in his address, and offers his thoughts in response.

  4. Recycling of lime sludge emanating from tannery industry through vermicomposting using Eisenia foetida.

    Science.gov (United States)

    Subash, Anitha; Gomathi, M; Kanagavalli, M; Sindhiya, D

    2012-07-01

    The research was focused on the control of pollution, which is caused due to tannery waste disposal, through the process of vermicomposting. Earthworms have increasingly been used for waste management. Therefore, the main aim of this study was to recycle the lime sludge emanating from a selected tannery industry through vermicomposting. Tannery solid waste was allowed to compost for 60 days, and then the composts were harvested and analyzed for selected physio-chemical and biochemical parameters. A flowering plant namely Tagets erecta Linn was grown in soil mixed with the vermicomposts obtained, and was studied for its growth attributes and compared with the control plant growth on soil alone. The attributes studied were biometric parameters, like root length, shoot length, plant height, plant weight, number of leaves, flowers and buds. The alkaline nature of the lime sludge was reduced to neutral range on vermicomposting. The electrical conductivity of the lime sludge was also reduced on vermicomposting which might be due to the transformation of complex organic compounds into simpler forms. The biochemical parameters, such as nitrogen and carbon were also reduced on vermicomposting.

  5. Heat Transfer and Flow Structure Evaluation of a Synthetic Jet Emanating from a Planar Heat Sink

    Science.gov (United States)

    Manning, Paul; Persoons, Tim; Murray, Darina

    2014-07-01

    Direct impinging synthetic jets are a proven method for heat transfer enhancement, and have been subject to extensive research. However, despite the vast amount of research into direct synthetic jet impingement, there has been little research investigating the effects of a synthetic jet emanating from a heated surface, this forms the basis of the current research investigation. Both single and multiple orifices are integrated into a planar heat sink forming a synthetic jet, thus allowing the heat transfer enhancement and flow structures to be assessed. The heat transfer analysis highlighted that the multiple orifice synthetic jet resulted in the greatest heat transfer enhancements. The flow structures responsible for these enhancements were identified using a combination of flow visualisation, thermal imaging and thermal boundary layer analysis. The flow structure analysis identified that the synthetic jets decreased the thermal boundary layer thickness resulting in a more effective convective heat transfer process. Flow visualisation revealed entrainment of local air adjacent to the heated surface; this occurred from vortex roll-up at the surface of the heat sink and from the highly sheared jet flow. Furthermore, a secondary entrainment was identified which created a surface impingement effect. It is proposed that all three flow features enhance the heat transfer characteristics of the system.

  6. Fracture toughness of rough and frictional cracks emanating from a re-entrant corner

    Directory of Open Access Journals (Sweden)

    Andrea Carpinteri

    2017-07-01

    Full Text Available In mixed-mode conditions, the competing contribution of the different stress intensity factors predicts fracture initiation load as well as crack propagation direction. Commonly, mixed-mode fracture resistance is based on the assumption of smooth and frictionless cracks. However, the effect of friction and roughness cannot be neglected when mixed mode loading occurs, as in the case of a crack emanating from a re-entrant corner. In this paper, the effect of friction and roughness is evaluated through a simple saw-tooth model in a three-quarter-infinite plane (corresponding to a 90 degree re-entrant corner. The crack surfaces are assumed to be globally smooth, and roughness and friction are incorporated through a constitutive law between opposite crack surfaces. The solution is found using the distributed dislocation method, and an iterative algorithm is needed due to the non-linearity of the model. The effect of friction and roughness angle is discussed for a simple case.

  7. 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.

  8. Stray dog trade fuelled by dog meat consumption as a risk factor for ...

    African Journals Online (AJOL)

    Background: Rabies is a preventable zoonosis with the highest case fatality of any disease in the world. In the developing world, it is transmitted mainly by dog bites. In parts of southern Nigeria, dog meat is a delicacy. Objective: To highlight trade in stray dogs as a major risk factor for rabies in animals and humans in ...

  9. 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.

  10. 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

  11. 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.

  12. 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...

  13. An advanced finite element reliability tool for stray current corrosion assessment

    NARCIS (Netherlands)

    Peelen, W.H.A.; Courage, W.M.G.

    2007-01-01

    This paper describes a model which simulates stray cuffent interference of underground steel structures through a traction power system, which causes accelerated corrosion Also the coupling of this model to a inhome developed reliability software package, Prob2B, is described. This coupling allows

  14. Gastrointestinal parasites in stray and shelter cats in the municipality of Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    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.

  15. 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...

  16. 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.

  17. ASPIICS/PROBA-3 formation flying solar coronagraph: Stray light analysis and optimization of the occulter

    Science.gov (United States)

    Landini, F.; Mazzoli, A.; Venet, M.; Vivès, S.; Romoli, M.; Lamy, P.; Massone, G.

    2017-11-01

    The "Association de Satellites Pour l'Imagerie et l'Interferometrie de la Couronne Solaire", ASPIICS, selected by ESA for the PROBA-3 mission, heralds the next generation of coronagraph for solar research, exploiting formation flying to gain access to the inner corona under eclipse-like conditions for long periods of time. A detailed description of the ASPIICS instrument and of its scientific objectives can be found in [1]. ASPIICS is distributed on the two PROBA 3 spacecrafts (S/C) separated by 150 m. The coronagraph optical assembly is hosted by the "coronagraph S/C" protected from direct solar disk light by the occulting disk on the "occulter S/C". The most critical issue in the design of a solar coronagraph is the reduction of the stray light due to the diffraction and scattering of the solar disk light by the occulter, the aperture and the optics. In the present article, we deal with two of these issues: - The analysis of the stray light inside the telescope. - The optimization of the external occulter edge, in order to eliminate the Poisson spot behind the occulter and to lower the stray light level going through the entrance pupil of the telescope. This work was performed in the framework of the ESA STARTIGER program which took place at the Laboratoire d'Astrophysique de Marseille (LAM) during a 6-month period from September 2009 to March 2010. In general, it is a very complicated task to combine the above two stray light issues together in the simulation and design phase as it requires to consider the propagation inside the telescope of the light diffracted by the external occulter. Actually, the present literature only reports diffraction calculations performed for simple occulting systems (i.e., two disks and serrated disk). A more pragmatic approach, also driven by the tight schedule of the STARTIGER program, is to separate the two contributions, and perform two different stray light analyses. This paper is dedicated to the description of both analyses

  18. The experimental study on the emanation power of a flow-through thoron source made from incandescent gas mantles.

    Science.gov (United States)

    Wang, Yunxiang; Zhang, Lei; Guo, Qiuju

    2017-12-18

    To improve the quality of the calibration of thoron concentration activity measurement, an experimental study on the emanation power of a flow-through thoron source based on incandescent gas mantles was carried out in this paper. The thoron activity concentrations of the outflowed air from the flow-through source were measured using RAD7, and the quantitative relationship between thoron concentrations and flowrates was studied through theoretical analysis, and the thoron emanation powers were obtained from the fitting of the relationship above. Results show that the thoron concentration decreased with the increasing flowrate in the gas path, and the thoron emanation powers of three batches of gas mantles obtained by fitting were 1.33% ± 0.17%, 0.77% ± 0.10% and 0.57% ± 0.07% respectively in low humidity condition. Those results were checked using the gamma spectroscopy method, and were consistent within the error range.

  19. The Applicability of Traditional Protection Methods to Lines Emanating from VSC-HVDC Interconnectors and a Novel Protection Principle

    Directory of Open Access Journals (Sweden)

    Shimin Xue

    2016-05-01

    Full Text Available Voltage source converter (VSC-based high voltage direct current (VSC-HVDC interconnectors can realize accurate and fast control of power transmission among AC networks, and provide emergency power support for AC networks. VSC-HVDC interconnectors bring exclusive fault characteristics to AC networks, thus influencing the performance of traditional protections. Since fault characteristics are related to the control schemes of interconnectors, a fault ride-through (FRT strategy which is applicable to the interconnector operating characteristic of working in four quadrants and capable of eliminating negative-sequence currents under unbalanced fault conditions is proposed first. Then, the additional terms of measured impedances of distance relays caused by fault resistances are derived using a symmetrical component method. Theoretical analysis shows the output currents of interconnectors are controllable after faults, which may cause malfunctions in distance protections installed on lines emanating from interconnectors under the effect of fault resistances. Pilot protection is also inapplicable to lines emanating from interconnectors. Furthermore, a novel pilot protection principle based on the ratio between phase currents and the ratio between negative-sequence currents flowing through both sides is proposed for lines emanating from the interconnectors whose control scheme aims at eliminating negative-sequence currents. The validity of theoretical analysis and the protection principle is verified by PSCAD/EMTDC simulations.

  20. 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...

  1. 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...

  2. Stray light assessment and mitigation for the DESI front-end optical system

    Science.gov (United States)

    Miller, Timothy N.; Lampton, Michael; Besuner, Robert W.; Sholl, Michael J.; Liang, Ming; Ellis, Scott

    2016-08-01

    The Dark Energy Spectroscopic Instrument (DESI) is under construction to measure the expansion history of the Universe, using the Baryon Acoustic Oscillation technique and the growth of structure using redshift-space distortions (RSD). The spectra of 40 million galaxies over 14000 square degrees will be measured during the life of the experiment. A new prime focus corrector for the KPNO Mayall telescope will deliver light to 5000 fiber optic positioners. The fibers in turn feed ten broad-band spectrographs. We will describe modeling and mitigation of stray light within the front end of DESI, consisting of the Mayall telescope and the corrector assembly. This includes the creation of a stray light model, quantitative analysis of the unwanted light at the corrector focal surface, identification of the main scattering sources, and a description of mitigation strategies to remove the sources.

  3. 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.

  4. 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

  5. Seroprevalence of Trypanosoma cruzi in stray and pet dogs in Grenada, West Indies.

    Science.gov (United States)

    Chikweto, A; Kumthekar, S; Chawla, P; Tiwari, K P; Perea, L M; Paterson, T; Sharma, R N

    2014-06-01

    American trypanosomiasis (Chagas disease) caused by the protozoan parasite Trypanosoma cruzi is endemic to parts of South America and the Caribbean. Infected dogs are important in the epidemiology of the parasite as they can play a role in the transmission of the parasite to humans. A total of 399 dog sera (242 stray and 157 pet dogs) were examined for T. cruzi infection; using a qualitative immunochromatographic dipstick test, based on recombinant antigens specific for American trypanosomiasis (Trypanosoma detect rapid test; InBios international, Inc., Seattle, Washington). Overall seroprevalence for T. cruzi was estimated at 10.5% (95% confidence interval: 7.5% to 13.5%); with stray dogs being significantly more affected (pdogs in Grenada are moderately exposed to T. cruzi compared to other areas in the region.

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

    OpenAIRE

    Sara Ravicini; Josep Pastor; Jennifer Hawley; Melissa Brewer; Jorge Castro-López; Melissa Beall; Michael R Lappin

    2016-01-01

    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 antib...

  7. On the matter of building high-frequency amplifiers minimally influenced by interstage stray reactances

    Science.gov (United States)

    A, Volkov Y.

    2017-01-01

    The expedience of building wideband multistage amplifiers, the stages of which are connected with each other so, that the “modes of impedance mismatch” are realized, is justified. Those modes allow us to reduce considerably the sensitivity of amplifier transfer factors to the stray (constructional) capacitances and inductances of interstage circuits. The procedure of synthesizing the schematics of such amplifiers is proposed, the efficiency and clarity of which are provided by using the method of signal graphs.

  8. Gastrointestinal Helminths and Ectoparasites in the Stray Cats (Felidae: Felis catus of Ahar Municipality, Northwestern Iran

    Directory of Open Access Journals (Sweden)

    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.

  9. Genotypic Characterization of Bordetella bronchiseptica Strains Isolated from Stray and Pet Dogs

    OpenAIRE

    Zafer Sayin1*, Asli Sakmanoglu1, Osman Erganis1, Uckun Sait Ucan1, Hasan Huseyin Hadimli1, Zeki Aras2, Gokcenur Sanioglu2 and Alp Aslan Coskun3

    2016-01-01

    Bordetella bronchiseptica (B. bronchiseptica) is the most important pathogen associated with kennel cough in dogs. The presence of B. bronchiseptica in pet dogs and shelter dogs with clinical respiratory disease was investigated in present study. The genetic relatedness among the strains was determined to evaluate the role of stray dogs in spread of B. bronchiseptica to pet dogs by detection of virulence genes such as filamentous hemagglutinin (fha), pertactin (prn) and dermonecrotic toxin (d...

  10. 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

  11. Effect of stray light correction of extreme-ultraviolet solar images in tomography

    Science.gov (United States)

    Lloveras, D. G.; Vásquez, A. M.; Shearer, P.; Frazin, R. A.

    2017-10-01

    The Extreme UltraViolet Imager (EUVI) telescope on board the Solar TErrestrial RElations Observatory (STEREO) mission provides extreme-ultraviolet (EUV) coronal images of the full Sun. Using time series of EUV images, the differential emission measure tomography (DEMT) technique allows the determination of the three-dimensional (3D) distribution of the coronal electron density and temperature in the inner corona. EUV images are affected by stray light contamination which can be effectively removed if the point-spread function (PSF) of the instrument is well determined, as it is the case for EUVI. We show the results of a detailed analysis of the impact of EUVI stray light removal in DEMT results. To this end we analyze Carrington Rotation (CR)-2081 during the last solar minimum, characterized by a highly axisymmetric coronal structure. We find that stray light decontamination of EUVI images implies a systematic decrease of the derived electron density scale height and a systematic increase of the derived coronal base density, while its effect on the derived temperature is not systematic neither significant. We detail the results of the analysis in quantitative fashion.

  12. Problems Associated with the Microchip Data of Stray Dogs and Cats Entering RSPCA Queensland Shelters

    Directory of Open Access Journals (Sweden)

    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.

  13. Molecular identification of hookworms in stray and shelter dogs from Guangzhou city, China using ITS sequences.

    Science.gov (United States)

    Liu, Y J; Zheng, G C; Zhang, P; Alsarakibi, M; Zhang, X H; Li, Y W; Liu, T; Ren, S N; Chen, Z X; Liu, Y L; Li, S J; Li, G Q

    2015-03-01

    Canine hookworm infections are endemic worldwide, with zoonotic transmission representing a potentially significant public health concern. This study aimed to investigate hookworm infection and identify the prevalent species from stray and shelter dogs in Guangzhou city, southern China by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) based on internal transcribed spacer (ITS) sequences. From March 2011 to July 2012, fresh faecal samples from a total of 254 dogs were obtained from five locations, namely Conghua, Baiyun, Liwan, Haizhu and Panyu, in Guangzhou. These samples were screened for the presence of hookworm eggs using light microscopy, with an overall prevalence of 29.53% being recorded. The highest prevalence of 45.28% was found in suburban dogs from Conghua compared with lower values recorded in urban dogs in Haizhu (21.43%), Baiyun (18.97%), Panyu (18.18%) and Liwan (15%). The prevalence in stray dogs was significantly higher than that in shelter dogs. PCR-RFLP analysis showed that 57.33% were detected as single hookworm infections with Ancyclostoma caninum, and 22.67% as A. ceylanicum, while 20% were mixed infections. This suggests that high prevalences of both hookworm species in stray and shelter dogs in China pose a potential risk of transmission from pet dogs to humans.

  14. 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

    2015-05-13

    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.

  15. Stray animal populations and public health in the South Mediterranean and the Middle East regions

    Directory of Open Access Journals (Sweden)

    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.

  16. 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.

  17. Survey of Dermatophytes in Stray Cats with and without Skin Lesions in Northern Italy

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    Daniela Proverbio

    2014-01-01

    Full Text Available The aim of this study was to determine the prevalence of dermatophytes in stray cats with and without clinical lesions from different colonies in rural and urban areas of Milan and surroundings in northern Italy. Stray cats (273 were caught during a trap-neuter-release (TNR program conducted in different colonies of northern Italy in both rural and urban areas. Each cat was examined in dark environment with a Wood’s lamp prior to sample collection. Hair or scales exhibiting typical fluorescence were removed with a pair of sterile hemostats and cultured. The hair of all cats was then sampled by Mackenzie modified brush technique regardless of the presence or absence of skin lesions attributable to dermatophytosis. All the hair samples were subjected to fungal culture. 15 cats were positive (5.5%. Microsporum canis was the most common dermatophyte isolated (13/15. The only other isolated dermatophyte was Trichophyton mentagrophytes (2/15. Our estimated prevalence of dermatophytes in stray cats was much lower than other Italian studies on the same population.

  18. Frequency of Piroplasms Babesia microti and Cytauxzoon felis in Stray Cats from Northern Italy

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    Eva Spada

    2014-01-01

    Full Text Available Emerging diseases caused by piroplasms pose a health risk for man and other animals, and domestic cats have been proposed as potential reservoirs for some piroplasm infections. The aim of this study was to identify the frequency of the piroplasms Babesia microti and Cytauxzoon felis in stray cats from northern Italy and to identify possible risk factors associated with these infections. Blood samples from 260 stray cats enrolled in a trap-neuter-release (TNR program in northern Italy were examined with conventional PCR for the presence of Babesia microti and Cytauxzoon felis DNA. No sample (0.0% tested positive for C. felis, whilst B. microti DNA was detected in two samples (0.8%. Both infected cats were in good clinical condition and recovered well from the neutering surgery. One of these two cats had a triple coinfection with Babesia microti, Candidatus Mycoplasma haemominutum, and Anaplasma phagocytophilum. Evidence presented in this study indicates that the blood borne protozoans Babesia microti and Cytauxzoon felis are not widely distributed in stray cat populations in Milan, northern Italy, and that the significance of cats as a reservoir host for B. microti in this area is limited.

  19. 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.,

  20. Prevalence of Dirofilaria immitis infection in stray cats by nested PCR in Korea.

    Science.gov (United States)

    Park, Hyung-Jin; Lee, Sang-Eun; Lee, Won-Ja; Oh, Jung-Hyun; Maheswaran, Easwaran; Seo, Kyoung-Won; Song, Kun-Ho

    2014-12-01

    The purpose of this study was to conduct a survey of Dirofilaria immitis infection among stray cats in Korea using nested PCR. We included 235 stray cats (121 females and 114 males) and evaluated each for the presence of feline heartworm infection. Blood samples were collected from 135 cats in Daejeon, 50 cats in Seoul, and 50 cats from Gyeonggi-do (Province). Of the 235 DNA samples, 14 (6.0%) were positive for D. immitis. The prevalence of infection in male cats (8/114, 7.0%) tended to be higher than that in female cats (6/121, 5.0%), but the difference was not statistically significant. In each location, 8, 2, and 4 cats were positive for infection, respectively, based on DNA testing. No significant differences in the prevalence were observed among the geographic regions, although the rate of infection was higher in Gyeonggi-do (8.0%) than Daejeon (5.9%) and Seoul (4.0%). We submitted 7 of the 14 D. immitis DNA-positive samples for sequencing analysis. All samples corresponded to partial D. immitis cytochrome c oxidase subunit I gene sequences with 99% homology to the D. immitis sequence deposited in GenBank (accession no. FN391553). To the best of our knowledge, this is the first survey using nested PCR to analyze the prevalence of D. immitis in stray cats in Korea.

  1. First genetic characterization of Toxoplasma gondii in stray cats from Algeria.

    Science.gov (United States)

    Yekkour, Feriel; Aubert, Dominique; Mercier, Aurélien; Murat, Jean-Benjamin; Khames, Mammar; Nguewa, Paul; Ait-Oudhia, Khatima; Villena, Isabelle; Bouchene, Zahida

    2017-05-30

    Toxoplasmosis is a parasitic disease with worldwide distribution and a major public health problem. In Algeria, no data are currently available about genotypes of Toxoplasma gondii isolated from animals or humans. The present study assesses for the first time the seroprevalence of toxoplasmosis in stray cats, and provides molecular characterization of T. gondii strains circulating in this feline population in Algiers, the capital city of Algeria. Sera from 96 stray cats were tested for the presence of antibodies against T. gondii using the modified agglutination test. The seroprevalence was 50% (48/96) using 1:6 as the positivity cut-off. Different organs samples from stray cats, including heart samples, were tested for the presence of Toxoplasma DNA using real-time PCR. T. Gondii DNA was detected in 90.6% (87/96) of hearts. Of these parasitic DNAs, 22 were submitted to genotyping through the analysis of 15 microsatellite markers. The identified genotypes (12 of 22) mainly belonged to the type II lineage. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. 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.

  3. modelling of far modelling of far-field mixing o field mixing o ambient

    African Journals Online (AJOL)

    User

    concentration variations become below th continuous and concentrated thereby causing a stret. Keywords: Far-field Mixing, Sacrificial Stretch,. Concentration Parameters. 1. INTRODUCTION. INTRODUCTION. INTRODUCTION. The mathematical physics of dispersion of indus effluent plumes emanating from conduit outfalls.

  4. Experience with the assessment of stray currents according to prEN 50122-2:2008; Erfahrungen mit der Streustrombewertung gemaess prEN 50122-2

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Christian [Fischer und Ehms KG, Halle (Germany); Thiede, Jens [ELBAS GmbH, Dresden (Germany)

    2008-07-01

    Direct-current traction systems have an impact on buried reinforced-concrete or metal structures due to the action of stray currents. The draft standard prEN 50122-2:2008 recommends a new measuring technique for the assessment of hazards caused by stray currents. Measurements made on tramway tracks and a d.c. railway in South Africa supplied initial experience for determining the stray current activity. (orig.)

  5. sup 2 sup 2 sup 6 Ra measurement in Mo, Cd and Nd sub 2 O sub 3 samples with the emanation method

    CERN Document Server

    Barabash, A S; Kornoukhov, V N; Orekhov, I V

    2001-01-01

    Measurements of sup 2 sup 2 sup 6 Ra content in materials and chemical reagents used to construct the double beta decay sources in the NEMO-3 experiment have been done with the emanation method technique. Three different radon emanation technologies were used in these studies. The first was the 'traditional' method of dissolving the sample. The second was an extraction of Rn from a melted sample and finally a technique of heating fine-grained powder was used. It is shown that there is good agreement of the data received with the emanation method and low background high purity germanium detectors. The sensitivity of this method is 0.02 mBq/l of solution (for the 'standard' emanation method) or 0.02 mBq/kg (for methods in which radon is extracted from a powder or melt).

  6. Correlation between radon gas emanation and porosity in ornamental stones; Correlacao entre emanacao de gas radonio e porosidade de rochas ornamentais do Estado do Ceara, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Azevedo, Leiliane Rufina Pereira de; Artur, Antonio Carlos; Bonotto, Daniel Marcos, E-mail: leili_ane@hotmail.com, E-mail: acartur@rc.unesp.br, E-mail: dbonotto@rc.unesp.br [Universidade Estadual Paulista (UNESP), Rio Claro, SP (Brazil); Nogueira Neto, Jose de Araujo, E-mail: nogueira@ufc.br [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Geologia

    2014-01-15

    This article makes correlations between levels of gas {sup 222}Rn emanation and corresponding porosity for thirteen samples of granitic rocks ornamental state of Ceara. For both determinations of physical indexes (bulk density, apparent porosity and water absorption, the levels of U, monitoring emanation of radon gas are made for a period of 25 days in confinement conditions of the samples under vacuum and petrographic studies of the characteristics rocks, with emphasis on the microfissural state. The sampled rocks provided low values of radon gas emanation between U 0,2 ppm and 13.6 ppm. The correlations between the various results show that the microporous network of the rock is determinant in the rate of emanation of radon gas, overlapping, including the influence of own levels of U present in the rocks. The results also show that the amount of radon gas emanating from the rock is small enough compared to the decay caused by the amount of {sup 238}U. The proposition of gas emanating relative to the total generated by rocks ranging between 0.4% and a maximum of 4.2%. (author)

  7. It’s a Dog’s Life: International Tourists’ Perceptions of the Stray Dog Population of Bhutan.

    Directory of Open Access Journals (Sweden)

    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.

  8. 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.

  9. Seroprevalence of leptospirosis in stray dogs from Patos city, state of Paraíba, Brazil

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    Carolina de Sousa Américo Batista

    2004-04-01

    Full Text Available This work aimed to survey the prevalence of leptospirosis in stray dogs from Patos city, state of Paraíba, Brazil. This study was held during the period of February to April of 2003, when 130 serum samples were collected. The diagnostic method run for leptospirosis was the microscopic agglutination test, using a batch of 22 leptospiral serovars. The most prevalent serovars were found crossing the results of frequency and titer of agglutinins. The results obtained indicated a prevalence of 20% and most frequent reactant serovars were autumnalis (20%, pomona (17,5%, grippotyphosa (10% e patoc (10%.

  10. The dog louse Heterodoxus spiniger from stray cats in Penang, Malaysia.

    Science.gov (United States)

    Norhidayu, S; Mohd Zain, S N; Jeffery, J; Lewis, J W

    2012-06-01

    Stray cats collected from Georgetown, Penang from 2008 to 2010 were screened for ectoparasites via fine-tooth combing. Two cats from a total 102 examined were infested with the dog louse, Heterodoxus spiniger. Both cats, a juvenile male and female were found in close contact with each other prior to capture. The number of lice ranged from 5 and 14 in the male and female cat respectively. Other ectoparasites recovered included the common cat flea, Ctenocephalides felis, one louse species Felicola subrostratus, one tick species Haemaphysalis bispinosa and one mite species of Listrophoridae. The present study reports for the first time the finding of H. spiniger on cats from peninsular Malaysia.

  11. Prevalence of Toxoplasma gondii antibodies, circulating antigens and DNA in stray cats in Shanghai, China

    Directory of Open Access Journals (Sweden)

    Wang Quan

    2012-09-01

    Full Text Available Abstract Background Toxoplasma gondii is prevalent in most areas of the world and may cause abortions or neonatal complications in humans. As the only definitive host, cats play an important role in the epidemiology of the disease. Infection rates in cats, especially stray or free-living cats, are considered to be the best sentinels of the level of T. gondii in the environment. The T. gondii infection can be diagnosed in different ways with different methods depending on the target. However, little information on T. gondii infection in cats was available in Shanghai, China. Moreover reports on prevalence of circulating antigens, antibodies and DNA of T. gondii in the same study are rare. Methods In the present study, the presence of antibodies (Ab, circulating antigens (CA, and/or DNA of Toxoplasma gondii in samples from 145 stray or unwanted cats from 6 animal shelters in Shanghai (China was determined in order to estimate the prevalence of T. gondii infection, by Ab-ELISA, CA-ELISA, and nested-PCR, respectively. Results The positive rates for the antibodies, circulating antigen and DNA of T. gondii were 11.7% (17 of 145, 5.5% (8 of 145 and 5.71% (2 of 35, respectively. No cat tested was positive by both the Ab-ELISA and the CA-ELISA, but the results of the PCR were consistent with the CA-ELISA assay. Therefore, the overall estimated prevalence of toxoplasmosis was 17.2% (25 of 145. According to our results, the positive rates of specific antibodies and circulating antigen of T. gondii were significantly different between adult cats (>1 year old and juvenile cats (≤1 year old; the former was 13.5% versus 3.9% by Ab-ELISA, while the latter was 1.7% versus 23.1% by CA-ELISA. From the results obtained with all three detection methods used in this study, the rate of infection was not significantly different between male and female cats (P ≥0.05; and the overall rate was 17.9% for males versus 16.4% for females. Conclusions The results

  12. Pulmonary Mycobacterium tuberculosis (Beijing strain infection in a stray dog : clinical communication

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    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.

  13. 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.

  14. 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.

    2015-06-01

    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.

  15. 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)

    Wilson, Lydia J; Newhauser, Wayne D

    2015-01-01

    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 minutes. 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. PMID:26040833

  16. Kejadian Dermatosis yang Tinggi pada Anjing Jalanan di Bali (A HAIGH DERMATOSIS INCIDENCE AMONG STRAY DOGS IN BALI

    Directory of Open Access Journals (Sweden)

    I Kadek Saka Wiryana

    2014-08-01

    Full Text Available This study was designed to investigate the incidence of dermatosis among stray dogs in Bali. A totalof 401 stray dogs collected in the animal shelter of Bali Animal Welfare Association during 2011 wasinvestigated in this study. Dogs were examined by the clinical sign and continued by skin scraping, cytologyand wood lamp examination. In total, 37,9% sample were positive for dermatosis. Bacterial causeddermatosis found to be the most prevalent (23,6%, followed by tick and fleas (16.5%, scabies (12.7%,malassezia (8.2%, demodek (8% and ringworm (4.5% respectively. We also found that dermatosis weremore prevalent in male dogs (50.9% rather than female dogs (32.9%. Dogs 9-12 weeks old were moreheavily infected (45.8% than other group. In conclusion, the incidence of dermatosis among stray dogs inBali is relatively high. This may need serious awareness as some of this dermatosis were zoonotic tohuman.

  17. 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.

  18. Molecular detection of blood pathogens and their impacts on levels of packed cell volume in stray dogs from Thailand

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    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.

  19. Stray electrical currents in laparoscopic instruments used in da Vinci® robot-assisted surgery: an in vitro study.

    Science.gov (United States)

    Mendez-Probst, Carlos E; Vilos, George; Fuller, Andrew; Fernandez, Alfonso; Borg, Paul; Galloway, David; Pautler, Stephen E

    2011-09-01

    The da Vinci(®) surgical system requires the use of electrosurgical instruments. The re-use of such instruments creates the potential for stray electrical currents from capacitive coupling and/or insulation failure. We used objective measures to report the prevalence and magnitude of such stray currents. Thirty-seven robotic instruments were tested using an electrosurgical unit (ESU) at pure coagulation and cut waveforms at four different settings. Conductive gel-coated instruments were tested at 40W, 80W, and maximum ESU output (coagulation 120W, cut 300W). The magnitude of stray currents was measured by an electrosurgical analyzer. At coagulation waveform in open air, 86% of instruments leaked a mean of 0.4W. In the presence of gel-coated instruments, stray currents were detected in all instruments with means (and standard deviation) of 3.4W (± 2), 4.1W (± 2.3), and 4.1W (± 2.3) at 40W, 80W, and 120W, respectively. At cut waveform in open air, none of the instruments leaked current, while gel-coated instruments leaked a mean of 2.2W (± 1.3), 2.2W (± 1.9) and 3.2W (± 1.9) at 40W, 80W, and 300W, respectively. All tested instruments in our study demonstrated energy leakage. Stray currents were higher during coagulation (high voltage) waveforms, and the magnitude was not always proportionate to the ESU settings. Stray currents have the potential to cause electrical burns. We support the programmed end of life of da Vinci instruments on the basis of safety. Consideration should be given to alternate energy sources or the adoption of active electrode monitoring technology to all monopolar instruments.

  20. 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%).

  1. Prevalence of Leishmania infantum and co-infections in stray cats in northern Italy.

    Science.gov (United States)

    Spada, Eva; Canzi, Ilaria; Baggiani, Luciana; Perego, Roberta; Vitale, Fabrizio; Migliazzo, Antonella; Proverbio, Daniela

    2016-04-01

    Stray cats in the city of Milan, Italy, were tested for Leishmania infantum and other selected infections. Twenty-seven cats (30.0%) were seroreactive by indirect fluorescent antibody test (IFAT), with an antibody titer of 1:40 for 16 (17.7%) cats and 1:80 (cut-off for feline L. infantum infection) for 11 (12.2%) cats. One blood (1.1%) and one popliteal lymph node (1.1%) sample tested positive by real-time polymerase chain reaction; no oculoconjunctival swabs tested positive. Feline immunodeficiency virus, feline leukemia virus, and feline coronavirus (FCoV) seroprevalence determined by enzyme-linked immunosorbent assay was 6.1, 6.1, and 39.0%, respectively. Toxoplasma gondii, Bartonella henselae, and Chlamydophila felis prevalence determined by IFAT was 29.3, 17.1, and 17.1%, respectively. The frequency of seroreactivity to L. infantum was significantly higher in FCoV-seropositive cats (OR=4.4, P=0.04). L. infantum-infected stray cats in Milan have a high seropositivity rate, comparable to that of cats in areas endemic for leishmaniosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Risk factors and effect of selective removal on retroviral infections prevalence in Belgian stray cats.

    Science.gov (United States)

    Garigliany, M; Jolly, S; Dive, M; Bayrou, C; Berthemin, S; Robin, P; Godenir, R; Petry, J; Dahout, S; Cassart, D; Thiry, E; Desmecht, D; Saegerman, C

    2016-01-09

    The aim of this study was to evaluate the effect of several risk/protective factors and predictors on the prevalence of feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV) infections in 302 stray cats captured during a trap-neuter-release programme in a mixed urban-rural area from Belgium, from 2010 to 2012. The impact of selective removal of FIV-positive cats on the apparent prevalence in the remaining population over this three-year period was also assessed. The seroprevalences over three years were 18.8 per cent for FIV and 0.7 per cent for FeLV. For FIV, the seroprevalence decreased significantly from the first year of the programme (2010; 30.5 per cent) to the last (2012; 13.1 per cent). Sex (male) and age (adult and old cats) were risk factors, while the year of sampling (years 2011 and 2012) was a protective factor. Age, sex and location were the most relevant predictors of FIV status. The data presented in this study revealed a very high FIV seroprevalence in Belgian stray cats, while FeLV was almost absent. The selective removal of positive cats had a drastic effect on the FIV seroprevalence in the remaining cat population. British Veterinary Association.

  3. Ectoparasites of Stray Dogs in Mazandaran, Gilan and Qazvin Provinces, North and Center of Iran

    Directory of Open Access Journals (Sweden)

    Elahe Ebrahimzade

    2016-01-01

    Full Text Available Background: The aim of the present study was to determine the prevalence of ectoparasite infestations in stray dogs in Mazandaran, Gilan and Qazvin Provinces in fall and winter in 2013(December to March.Methods: Seventy dogs in 2013, from these Provinces were examined for ectoparasite infestation and diagnosis of them based on parasitological methods and identification keys was done.Results: The rate of infestation in these areas was 100%, 68.5% and 93.3% respectively. Fleas were the most com­mon ectoparasites on dogs in this study followed by lice, ticks, flies and mites respectively. The isolated arthropods were fleas in 77.5%, lice in 50%, ticks in 8.6%, flies in 6.8% and mites in 5.1% of infested dogs. The ectoparasite of the dogs included 4 flea species: Ctenocephalides canis (29.8%, C. felis (19.9%, Pulex iritans (2.9% and Xenopsi­ella cheopis (0.7%, 1 louse species: Trichodectes canis (41.3%, 1 tick species: Rhipicephalus sanguinus (0.7%, 1 fly species: Hippobosca sp. (1.1% and 1 mite species: Sarcoptes scabiei (3.6%.Conclusion: Fleas and lice were the most common ectoparasites in stray dogs of the studied area. Some ectopara­sites transmit important human disease, therefore regular monitoring of them is a major concern to control the ar­thropods and arthropods-borne diseases.

  4. Gastrointestinal Helminthic Parasites in Stray Cats (Felis catus from North of Iran

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    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.

  5. Helminth Infections of Stray Dogs from Garmsar, Semnan Province, Central Iran

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    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.

  6. 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.

  7. Zoonotic Parasites of Sheltered and Stray Dogs in the Era of the Global Economic and Political Crisis.

    Science.gov (United States)

    Otranto, Domenico; Dantas-Torres, Filipe; Mihalca, Andrei D; Traub, Rebecca J; Lappin, Michael; Baneth, Gad

    2017-10-01

    Sheltered and stray dogs, exposed to zoonotic parasites, including protozoa, helminths, and arthropods, may represent a major threat to public health. Resources for addressing health problems in these animals are not on the priority list of veterinary and public health authorities. Thus, dogs continue to represent an important reservoir for zoonotic parasites. In this article, we review the importance of sheltered and stray dogs as reservoirs of zoonotic parasites in different parts of the world, especially in the context of the current global political and economic crisis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. 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.

    Science.gov (United States)

    Jay-Russell, Michele T; Hake, Alexis F; Bengson, Yingjia; Thiptara, Anyarat; Nguyen, Tran

    2014-01-01

    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 produce

  9. 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

  10. Estimate of Gaseous 14Carbon Concentrations Emanating from the Intermediate-Level Vault Disposal Facility

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, D

    2005-08-31

    {sup 14}Carbon-bearing resin waste will be disposed in the Low-Activity Waste (LAW) Intermediate Level Vaults (ILV) located in E-Area on the Savannah River Site (SRS). This waste will be buried in a cementitious environment in the vadose zone, i.e., the subsurface zone above the aquifer. As the resin ages, and equilibrates with slowly infiltrating water, it is expected that the {sup 14}C will partition to the solid, liquid, and gaseous phases. The objective of this task was to estimate the concentration of gaseous {sup 14}C in the waste pore space that is in contact with the resin leachate. The approach used to estimate this value was built largely around data generated from lysimeter studies that were conducted for 9 years. These lysimeters contained the same type of used resins (mixed-bed deionizer resins used in the purification of the heavy water moderator of SRS reactors) as are being disposed in the ILV. During the 9 year period, pore water {sup 14}C leaching concentrations were monitored to provide an excellent estimate of the long-term behavior of {sup 14}C release rates from the resins. Thermodynamic calculations were conducted to calculate {sup 14}CO{sub 2(g)} concentrations. These calculations included the {sup 14}C pore water data from the lysimeter study, and data from a field study that was a natural analogue to a long-term cementitious environment (Khoury et al. 1992). The calculations predicted an extremely low {sup 14}CO{sub 2(g)} concentration of 1.9 x 10{sup -7} Ci/m{sup 3} {sup 14}CO{sub 2(g)} in the air spaces above the resin leachate. This low concentrations is not surprising in light of both laboratory and field observations that concrete acts as a strong sorbent of CO{sub 2(g)}. This calculated {sup 14}CO{sub 2(g)} concentration will now be included in future risk calculations.

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

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    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.

  12. PENERAPAN MODEL PEMBELAJARAN TWO STAY TWO STRAY BERBANTUAN KARTU SOAL UNTUIK MENINGKATKAN HASIL BELAJAR

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    Ratna Sinthia Dewi

    2014-06-01

    Full Text Available Penelitian ini bertujuan untuk membuktikan keefektifan model pembelajaran Two Stay Two Stray (TSTS berbantua Kartu soal dalam meningkatkan hasil belajar akuntansi kompetensi dasar penyusunan laporan keuangan oerusahaan jasa di SMA Negeri 1 Karanganom tahun ajaran 2013/2014. Penelitian ini merupakan penelitian quasi eksperimen yang dirancang menggunakan Nonequivalent Control Group Design. Sampel penelitian diambil dengan teknik pair matching, diperoleh kelas XI IPS 3 sebagai kelas eksperimen dan kelas XI IPS 1 sebagai kelas kontrol. Metode pengumpulan data yaitu metode tes dan observasi. Analisis data hasil belajar ((sebelum perlakuan (statistik deskriptif, normalitas, homogenitas, kesamaan dua rata-rata dan setelah perlakuan (statistik deskriptif, normalitas, homogenitas, uji hipotesis. Hasil penelitian menunjukkan bahwa penerapan model pembelajaran TSTS berbantuan media kartu soal dapat meningkatkan hasil belajar serta lebih efektif dalam meningkatkan hasil belajar akuntansi kompetensi dasar penyusunan laporan keuangan perusahaan jasa dibandingkan model pembelajaran konvensional. Saran dari penelitian ini adalah guru dapat menerapkan model pembelajaran TSTS berbantuan media kartu soal sebagai salah satu variasi model dan media pembelajaran akuntansi yang dapat meningkatkan hasil belajar siswa dalam pembelajaran. Tapi dalam penerapannya harus memperhatikan keterbatasannya agar dapat berfungsi secara maksimal. This study aims to prove the effectiveness of the learning model Two Stay Two Stray (TSTS assisted problem card media on learning outcomes of the preparation of the financial statement services company of accounting competence in Karanganom 1st State Senior High School academic year 2013/2014. This study is quasi experimental research that designed with nonequivalent control group design. Samples were taken with pair matching sampling Technique, obtained in class XI IPS 3 as the experimental class and class XI IPS 1 as the control class

  13. Multiwavelength study of 20 jets that emanate from the periphery of active regions

    Science.gov (United States)

    Mulay, Sargam M.; Tripathi, Durgesh; Del Zanna, Giulio; Mason, Helen

    2016-05-01

    Aims: We present a multiwavelength analysis of 20 EUV jets which occurred at the periphery of active regions close to sunspots. We discuss the physical parameters of the jets and their relation with other phenomena such as Hα surges, nonthermal type-III radio bursts and hard X-ray (HXR) emission. Methods: These jets were observed between August 2010 and June 2013 by the Atmospheric Imaging Assembly (AIA) instrument that is onboard the Solar Dynamic Observatory (SDO). We selected events that were observed on the solar disk within +/-60° latitude. Using AIA wavelength channels that are sensitive to coronal temperatures, we studied the temperature distribution in the jets using the line of sight (LOS) differential emission measure (DEM) technique. We also investigated the role of the photospheric magnetic field using the LOS magnetogram data from the Helioseismic and Magnetic Imager (HMI) onboard SDO. Results: It has been observed that most of the jets originated from the western periphery of active regions. Their lifetimes range from 5 to 39 min with an average of 18 min and their velocities range from 87 to 532 km s-1 with an average of 271 km s-1. All the jets are co-temporally associated with Hα surges. Most of the jets are co-temporal with nonthermal type-III radio bursts observed by the Wind/WAVES spacecraft in the frequency range from 20 kHz to 13 MHz. We confirm the source region of these bursts using the potential field source surface (PFSS) technique. Using Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) observations, we found that half of the jets produced HXR emission and they often shared the same source region as the HXR emission (6-12 keV). Ten out of 20 events showed that the jets originated in a region of flux cancellation and six jets in a region of flux emergence. Four events showed flux emergence and then cancellation during the jet evolution. DEM analyses showed that for most of the spires of the jets, the DEM peaked at around log

  14. PENGARUH PEMBELAJARAN KOOPERATIF TWO STAY TWO STRAY BERPENDEKAT AN SETS TERHADAP HASIL BELAJAR KIMIA SISWA SMA NEGERI 1 COMAL

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    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.

  15. 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

    2014-08-01

    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. The current study aimed to investigate the prevalence of parasites in stray cats in Ahvaz. 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. 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). 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.

  16. Study of the influence of porosity on the radon emanation coefficient in different building material samples by combining the SSNTD technique with Monte Carlo simulations

    CERN Document Server

    Misdaq, M A; Ktata, A

    1998-01-01

    Radon alpha-activities per unit volume have been measured inside and outside different building material samples by using CR-39 and LR-115 type II solid state nuclear track detectors (SSNTD). Radon emanation coefficients of the studied building materials have been evaluated. The porosities of the building material samples studied have been determined by using a Monte Carlo calculational method adapted to the experimental conditions and compared with data obtained by the Archimedes's method. The influence of the building material porosity on the radon emanation coefficient has been investigated.

  17. Suppression of stray interference peaks of optical joint in white light interferometer

    Science.gov (United States)

    Cheng, Yongqing; Yang, Jun; Yuan, Yonggui; Zhang, Haoliang; Yang, Zhe; Lv, Yan; Yuan, Libo

    2017-04-01

    The stray interference peaks (SIPs) are an important factor resulting in the misjudgment of measurement information in white light interferometer (WLI). SIPs are generated by the residual reflected light beams. We theoretically analyze the interference conditions of the SIP. The analysis shows that these SIPs are discrete main interference peak outside and have different orders. We present a stagger optical path (SOP) method for suppressing or eliminating these SIP which will appear in the interference pattern. The SOP means that there is an appropriate fiber length determined by the delay amount of delay line between each joint. Moreover, an experiment with two joints, for simplicity, is given as an example. Experimental results show that the high-order SIP from the joints can be suppressed by the SOP to obtain a clean interference pattern.

  18. J-Black: a stray light coating for optical and infrared systems

    Science.gov (United States)

    Waddell, Patrick; Black, David S.

    2016-07-01

    A new stray light coating, called J-Black, has been developed for NASA's Stratospheric Observatory for Infrared Astronomy (SOFIA). The coating is a layered composition of Nextel-Suede 3101 primers and top coats and silicon carbide grit. J-Black has been applied to large areas of the SOFIA airborne telescope and is currently operating within the open cavity environment of the Boeing 747. Over a series of discrete filter bands, from 0.4 to 21 microns, J-Black optical and infrared reflectivity performance is compared with other available coatings. Measured total reflectance values are less than 2% at the longest wavelengths, including at high incidence angles. Detailed surface structure characteristics are also compared via electron and ion microscopy. Environmental tests applicable for aerospace applications are presented, as well as the detailed steps required to apply the coating.

  19. 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.

  20. Identification of a Chicken Anemia Virus Variant-Related Gyrovirus in Stray Cats in China, 2012

    Directory of Open Access Journals (Sweden)

    Xinheng Zhang

    2014-01-01

    Full Text Available The chicken anemia virus (CAV, is a known member of the genus Gyrovirus and was first isolated from chickens in Japan in 1979. Some reports have also demonstrated that CAV can be identified in human stool specimens. In this study, a variant of CAV was detected using PCR with CAV-based primers in fecal samples of stray cats. The genome of CAV variant was sequenced and the results suggest that it could be a recombinant viral strain from parental CAV strains JQ690762 and AF311900. Recombination is an important evolutionary mechanism that contributes to genetic diversification. These findings indicate that CAV variant might have originated from CAV-infected chickens. The epidemiology and pathogenesis of this novel virus remains to be elucidated. This study underscores the importance of CAV surveillance and it presents the first evidence suggesting the possibility of CAV homologous recombination in cat.

  1. Frequency of antibodies to Toxoplasma gondii in stray dogs of Oaxaca, México.

    Science.gov (United States)

    Cedillo-Peláez, C; Díaz-Figueroa, I D; Jiménez-Seres, M I; Sánchez-Hernández, G; Correa, D

    2012-08-01

    We studied the frequency of antibodies against Toxoplasma gondii in stray dogs in the city of Oaxaca, Mexico through the evaluation of 154 sera by indirect ELISA. A frequency of 61.7% was found; it was higher in males (45 of 65, 69.2%) than in females (49 of 89, 55.0%), although this difference was not statistically significant. An increase in frequency was observed with age, the lowest being among animals younger than 1 yr (4 of 20, 20.0%) and the highest in dogs older than 7 yr (21 of 25, 84.0%). This is the first study in dogs of this region of Mexico and revealed high T. gondii transmission and evidence of early exposure in animals that are in close contact with contaminated water or raw meat, or both. Further studies are needed in order to understand the role of T. gondii infection in public health.

  2. 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.

  3. Size and spatial distribution of stray dog population in the University of São Paulo campus, Brazil.

    Science.gov (United States)

    Dias, Ricardo Augusto; Guilloux, Aline Gil Alves; Borba, Mauro Riegert; Guarnieri, Maria Cristina de Lourdes; Prist, Ricardo; Ferreira, Fernando; Amaku, Marcos; Neto, José Soares Ferreira; Stevenson, Mark

    2013-06-01

    A longitudinal study was carried out to describe the size and spatial distribution of the stray dog population in the University of São Paulo campus, Brazil from November 2010 to November 2011. The campus is located within the urban area of São Paulo, the largest city of Brazil, with a population over 11 million. The 4.2 km(2) that comprise the university grounds are walled, with 10 access gates, allowing stray dogs to move in and out freely. Over 100,000 people and 50,000 vehicles circulate in the campus daily. Five observations were made during the study period, using a mark-resight method. The same route was performed in all observations, being traveled twice on each observation day. Observed animals were photographed and the sight coordinates were obtained using a GPS device. The estimated size of the stray dog population varied from 32 (CI 95% 23-56) to 56 (CI 95% 45-77) individuals. Differences between in- and outward dog movements influenced dog population estimates. Overlapping home ranges of docile dogs were observed in areas where most people circulate. An elusive group was observed close to a protected rain forest area and the estimated home range for this group did not overlap with the home ranges for other dogs within the campus. A kernel density map showed that higher densities of stray dog sighting is associated with large organic matter generators, such as university restaurants. We conclude that the preferred source of food of the stray dogs on the University of São Paulo campus was leftover food deliberately offered by restaurant users. The population was stable during the study period and the constant source of food was the main reason to retain this population within the campus. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Genetic Characterization of Toxoplasma gondii Isolates and Toxoplasmosis Seroprevalence in Stray Cats of İzmir, Turkey

    Science.gov (United States)

    Can, Hüseyin; Döşkaya, Mert; Ajzenberg, Daniel; Özdemir, H. Gökhan; Caner, Ayşe; İz, Sultan Gülce; Döşkaya, Aysu Değirmenci; Atalay, Esra; Çetinkaya, Çağdaş; Ürgen, Saygun; Karaçalı, Sabire; Ün, Cemal; Dardé, Marie-Laure; Gürüz, Yüksel

    2014-01-01

    Currently, some Toxoplasma gondii genotypes are being associated with serious clinical presentations. A recent report showing the Africa 1 genotype in two local congenital toxoplasmosis cases acquired in Turkey formed the basis of this study because atypical Africa 1 genotype is most frequently detected in animals and patients from sub-Saharan Africa. Since stray cats are considered as the linkage between wild life and urban life in T. gondii transmission, the present study aimed to isolate and characterize T. gondii strains circulating in stray cats of İzmir (Western Turkey). A secondary objective was to determine toxoplasmosis seroprevalence in this cat population. Tissues obtained from 100 deceased stray cats were bioassayed and isolated strains were genotyped using 15 microsatellite markers. In addition, toxoplasmosis seroprevalence was analyzed in 1121 cat sera collected from several large veterinary clinics in İzmir. Among the 22 isolates, 19 were Type II (86.3%), two were Type III (9%) and one was Africa 1 genotype (4.5%). The overall seropositivity rates in cats were 42–48% and 33.4–34.4% according to IFA and ELISA, respectively. Seroprevalence in deceased cats was significantly higher than in healthy cats (P = 0.0033). Finding both the major clonal Type II lineage together with the Type III lineage also found in Middle East, and an atypical genotype, Africa 1 appears consistent with the specific geographic location of Turkey between three continents and raises the possibility of transportation of these strains between continents through trade routes or long distance migratory birds. In addition, the first large study of toxoplasma seroprevalence in a stray cat population was also reported. The relatively high seropositivity rates and the variety of T. gondii genotypes confirm the local stray cat population as a risk factor for human toxoplasmosis in İzmir. PMID:25127360

  5. Genetic characterization of Toxoplasma gondii isolates and toxoplasmosis seroprevalence in stray cats of İzmir, Turkey.

    Directory of Open Access Journals (Sweden)

    Hüseyin Can

    Full Text Available Currently, some Toxoplasma gondii genotypes are being associated with serious clinical presentations. A recent report showing the Africa 1 genotype in two local congenital toxoplasmosis cases acquired in Turkey formed the basis of this study because atypical Africa 1 genotype is most frequently detected in animals and patients from sub-Saharan Africa. Since stray cats are considered as the linkage between wild life and urban life in T. gondii transmission, the present study aimed to isolate and characterize T. gondii strains circulating in stray cats of İzmir (Western Turkey. A secondary objective was to determine toxoplasmosis seroprevalence in this cat population. Tissues obtained from 100 deceased stray cats were bioassayed and isolated strains were genotyped using 15 microsatellite markers. In addition, toxoplasmosis seroprevalence was analyzed in 1121 cat sera collected from several large veterinary clinics in İzmir. Among the 22 isolates, 19 were Type II (86.3%, two were Type III (9% and one was Africa 1 genotype (4.5%. The overall seropositivity rates in cats were 42-48% and 33.4-34.4% according to IFA and ELISA, respectively. Seroprevalence in deceased cats was significantly higher than in healthy cats (P = 0.0033. Finding both the major clonal Type II lineage together with the Type III lineage also found in Middle East, and an atypical genotype, Africa 1 appears consistent with the specific geographic location of Turkey between three continents and raises the possibility of transportation of these strains between continents through trade routes or long distance migratory birds. In addition, the first large study of toxoplasma seroprevalence in a stray cat population was also reported. The relatively high seropositivity rates and the variety of T. gondii genotypes confirm the local stray cat population as a risk factor for human toxoplasmosis in İzmir.

  6. 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.

  7. 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.

  8. Effect of Primary Dendrite Orientation on Stray Grain Formation in Cross-Section Change Region During the Directional Solidification of Ni-Based Superalloy

    Science.gov (United States)

    Xuan, Weidong; Li, Chuantao; Zhao, Dengke; Wang, Baojun; Li, Chuanjun; Ren, Zhongming; Zhong, Yunbo; Li, Xi; Cao, Guanghui

    2017-02-01

    The effect of primary dendrite orientation on stray grain formation in a cross-section change region during the directional solidification of Ni-based superalloy is investigated through both experimental observations and numerical simulation. The results clearly show that the orientation of primary dendrite affects the formation of stray grains in the cross-section change region. It is observed that, for the primary dendrite without misorientation, no stray grain is formed in the cross-section change region; for the primary dendrite with a moderate misorientation (15 deg), stray grains are formed only on the side converging from the mold wall in the cross-section change region. When the misorientation is 25 deg, stray grains are formed on both the side converging from the mold wall and the side diverging from the mold wall in the cross-section change region (the converging side and the diverging side for short). The simulation results are in accordance with experimental results. Furthermore, the correlation among factors such as stray grain formation, primary dendrite orientation, and withdrawal velocity has been analyzed. The mechanism of stray grain formation in various oriented primary dendrites is discussed.

  9. [Book review] Ecology, biogeography and management of Pinus halepensis and P. brutia forest ecosystems in the Mediterranean Basin, by G. Ne'eman and L. Trabaud

    Science.gov (United States)

    Keeley, J.E.

    2001-01-01

    Review of: Ne'eman, G. & Trabaud, L. Ecology, Biogeography and Management of Pinus halepensis and P. brutia Forest Ecosystems in the Mediterranean Basin. xii + 412 pp. Backhuys Publishers, Leiden. ISBN 90?5782-055-2 (hardcover). Price: USD 120.00.

  10. Genetic evidence of enzootic leishmaniasis in a stray canine and Texas mouse from sites in west and central Texas

    Directory of Open Access Journals (Sweden)

    Evan J Kipp

    Full Text Available We detected Leishmania mexicana in skin biopsies taken from a stray canine (Canis familiaris and Texas mouse (Peromyscus attwateri at two ecologically disparate sites in west and central Texas using polymerase chain reaction (PCR. A single PCR-positive dog was identified from a sample of 96 stray canines and was collected in a peri-urban area in El Paso County, Texas. The PCR-positive P. attwateri was trapped at a wildlife reserve in Mason County, Texas, from a convenience sample of 20 sylvatic mammals of different species. To our knowledge, this represents the first description of L. mexicana in west Texas and extends the known geographic range of the parasite to an area that includes the arid Chihuahuan Desert. Our finding of L. mexicana in P. attwateri represents a new host record and is the first description of the parasite in a wild peromyscid rodent in the United States.

  11. Genetic evidence of enzootic leishmaniasis in a stray canine and Texas mouse from sites in west and central Texas.

    Science.gov (United States)

    Kipp, Evan J; Mariscal, Jacqueline; Armijos, Rodrigo X; Weigel, Margaret; Waldrup, Kenneth

    2016-10-01

    We detected Leishmania mexicana in skin biopsies taken from a stray canine (Canis familiaris) and Texas mouse (Peromyscus attwateri) at two ecologically disparate sites in west and central Texas using polymerase chain reaction (PCR). A single PCR-positive dog was identified from a sample of 96 stray canines and was collected in a peri-urban area in El Paso County, Texas. The PCR-positive P. attwateri was trapped at a wildlife reserve in Mason County, Texas, from a convenience sample of 20 sylvatic mammals of different species. To our knowledge, this represents the first description of L. mexicana in west Texas and extends the known geographic range of the parasite to an area that includes the arid Chihuahuan Desert. Our finding of L. mexicana in P. attwateri represents a new host record and is the first description of the parasite in a wild peromyscid rodent in the United States.

  12. 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.

  13. Signals emanating from the membrane proximal region of the thrombopoietin receptor (mpl) support hematopoietic stem cell self-renewal.

    Science.gov (United States)

    Tong, Wei; Ibarra, Yessenia M; Lodish, Harvey F

    2007-09-01

    Studies using thrombopoietin -/- (TPO(-/-)) or TPO receptor, mpl(-/-) mice have established a critical role for TPO/mpl signaling in hematopoietic stem cell (HSC) development. In this study, we further dissected mpl signaling in both megakaryopoiesis and HSC function, using mice bearing a truncated mpl receptor lacking the distal 60 amino acids (Delta60). This deletion removes three major signaling tyrosines on the mpl cytoplasmic domain, but retains the membrane proximal Box1 and Box2 domains required for JAK2 activation. Competitive bone marrow transplantations (BMT) and serial BMTs were performed to study HSC function. Western blot analysis was used to study TPO-stimulated signaling pathways. BM cell cultures in the presence of TPO were used to study megakaryocyte development. In agreement with prior findings, we show that Delta60 BM cells cultured in TPO generated normal numbers of megakaryocytes, but with greatly reduced ploidy. As expected from the deletion of three signaling tyrosine residues, freshly isolated Delta60 megakaryocytes showed marked reduction in all known TPO-stimulated signaling pathways tested, including signal transducers and activators of transcription (Stat) 5, Stat3, Akt, and p42/44 mitogen-activated kinase. We found that Delta60 mice displayed normal short-term (ST-HSC) activities and marginally compromised long-term (LT-HSC) stem cell activities in primary transplantation. In addition, Delta60 mice supported HSC self-renewal for at least two serial BMTs. Our data reveal a pivotal role for an unknown signal emanating from the membrane proximal region of the mpl receptor or from JAK2 itself in maintaining stem cell activity and self-renewal, in addition to its role in megakaryocytopoiesis and thrombopoiesis.

  14. Prevalence, risk factors and genetic characterization of Toxoplasma gondii in sick pigs and stray cats in Jiangsu Province, eastern China.

    Science.gov (United States)

    Hou, Zhao-Feng; Su, Shi-Jie; Liu, Dan-Dan; Wang, Le-le; Jia, Chuan-Li; Zhao, Zhen-Xing; Ma, Yi-Fei; Li, Qiao-Qiao; Xu, Jin-Jun; Tao, Jian-Ping

    2018-02-13

    Toxoplasma gondii is an obligate intracellular parasitic protozoan with a worldwide distribution. The parasites in edible tissues of pigs and oocysts from cats are the major sources of T. gondii infection in humans. However, there are no data from sick pigs in veterinary clinics or from stray cats in Jiangsu Province, eastern China. In total, biological samples from 141 sick pigs and 64 stray cats were collected from this region. The rate of T. gondii infection in sick pigs was 46.81% using a polymerase chain reaction (PCR), and the overall prevalence of toxoplasmosis in stray cats was 34.38% by PCR and an enzyme-linked immunosorbent assay (ELISA). T. gondii was significantly more prevalent in lungs and heart than in liver and spleen (P < 0.05). Age and geographic region were considered to be the main risk factors associated with T. gondii infection in these pigs. The DNA samples from 17 sick pigs and seven stray cats, were successfully genotyped by multilocus PCR-restriction fragment length polymorphism (PCR-RFLP) with 10 genetic markers [SAG1, SAG2 (5'-3'SAG2, alt. SAG2), SAG3, GRA6, PK1, c22-8, c29-2, BTUB, L358 and Apico]. Six distinct genotypes were found, which were designated ToxoDB PCR-RFLP genotypes #9 (Chinese I), #10 (Type I), #213, and #89, and New 1 and New 2. Chinese I is the most prevalent T. gondii genotype in this region. The two new genotypes (designated New 1 and New 2) are reported and the ToxoDB PCR-RFLP genotype #89 is found for the first time in China. Such information will be useful for the prevention, diagnosis and treatment of porcine toxoplasmosis in Jiangsu Province, eastern China. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Seroprevalence and Risk Factors Associated with Seropositivity to Toxoplasma gondii among Stray and Domestic Cats (Felis silvestris catus

    Directory of Open Access Journals (Sweden)

    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.

  16. Protective immune response of oral rabies vaccine in stray dogs, corsacs and steppe wolves after a single immunization.

    Science.gov (United States)

    Zhugunissov, K; Bulatov, Ye; Taranov, D; Yershebulov, Z; Koshemetov, Zh; Abduraimov, Ye; Kondibayeva, Zh; Samoltyrova, A; Amanova, Zh; Khairullin, B; Sansyzbay, A

    2017-11-01

    In this study the safety and protective immunity of an oral rabies vaccine, based on the live, modified rabies virus strain VRC-RZ2, was examined in stray dogs (Canis Sp.), corsacs (Vulpes corsac) and steppe wolves (Canis lupus campestris). In the safety group (dogs, n=6; corsacs, n=3; wolves, n=3) which was vaccinated with a 10-times field dose/animal, no animals showed any signs of disease or changes in behavior or appetite during the period of clinical observation, similar to the animals in the negative control group. Saliva samples taken from animals prior and post (5 th and 10 th days) vaccination failed to demonstrate rabies virus antigen. Observations of immunogenicity in vaccinated carnivores (dogs, corsacs and wolves) during a 180 day period showed the titers of virus neutralizing antibodies (VNA) in the blood sera of vaccinated dogs to be within 0.59-1.37 IU/mL. On 14 days post vaccination (dpv), all the wild carnivores had detectable levels of neutralizing antibodies, with mean titers ranging from 0.50 ± 0.07 IU/mL (for wolves) to 0.59 ± 0.10 IU/mL (for corsacs). Weeks after vaccination, all the vaccinated wolves and corsacs had higher levels of neutralizing antibodies: 0.70 ± 0.10 - 0.71 ± 0.08 IU/mL at 30 dpv, 1.06 ± 0.08 - 1.28 ± 0.21 IU/mL at 60 dpv and 0.41 ± 0.09 - 047 ± 0.06 at 180 dpv. The highest level of VNA (˃1.0 IU/ml) was detected at 60 dpv, in all vaccinated animals. After challenge all vaccinated dogs remained healthy for 180 days. Control animals (unvaccinated dogs) developed symptoms of rabies on day 6 post administration of a virulent virus and died of rabies on days 11-13. Of note, the VNA titers in all the wild carnivores (corsacs and wolves) immunized with VRC-RZ2 were higher than 0.5 IU/ml (0.59 ± 0.11 IU/ml), even as early as 14 days post vaccination. These, presumably protective, titers of antibodies to rabies virus were present in the dogs and wild carnivores examined in this study for at

  17. 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.

  18. 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.

  19. Toxocara nematodes in stray cats from shiraz, southern iran: intensity of infection and molecular identification of the isolates.

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    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.

  20. Prevalence of swine viral and bacterial pathogens in rodents and stray cats captured around pig farms in Korea.

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    Truong, Quang Lam; Seo, Tae Won; Yoon, Byung-Il; Kim, Hyeon-Cheol; Han, Jeong Hee; Hahn, Tae-Wook

    2013-12-30

    In 2008, 102 rodents and 24 stray cats from the areas around 9 pig farms in northeast South Korea were used to determine the prevalence of the following selected swine pathogens: ten viral pathogens [porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), rotavirus, classical swine fever virus (CSFV), porcine circovirus type 2 (PCV2), encephalomyocarditis virus (EMCV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine parvovirus (PPV), pseudorabies virus (PRV) and Japanese encephalitis virus (JEV)] and four bacterial pathogens (Brucella, Leptospira, Salmonella and Lawsonia intracellularis). In total, 1,260 tissue samples from 102 rodents and 24 stray cats were examined by specific PCR and RT-PCR assays, including tissue samples of the brain, tonsils, lungs, heart, liver, kidneys, spleen, small intestine, large intestine and mesenteric lymph nodes. The percentages of PCR-positive rodents for the porcine pathogens were as follows: 63.7% for Leptospira, 39.2% for Brucella, 6.8% for Salmonella, 15.7% for L. intracellularis, 14.7% for PCV2 and 3.9% for EMCV. The percentages of PCR-positive stray cats for the swine pathogens were as follows: 62.5% for Leptospira, 25% for Brucella, 12.5% for Salmonella, 12.5% for L. intracellularis and 4.2% for PEDV. These results may be helpful for developing control measures to prevent the spread of infectious diseases of pigs.

  1. Hematology and serum chemistry reference values of stray dogs in Bangladesh

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    N. Haider

    2011-02-01

    Full Text Available Hematology and serum chemistry values were obtained from 28 male and 22 female stray dogs in Chittagong Metropolitan area, Bangladesh. The goal of the study was to establish reference value for hematology and serum chemistry for these semi wild animals in relation to age, sex, reproductive stage and body condition. No significant differences were found for mean values of hemoglobin, packed cell volume, mean corpuscular hemoglobin concentration, white blood cell, differential leukocyte count, total protein, albumin, glucose, cholesterol, phosphorus and potassium among or between sexes, ages, reproductive states or body conditions. Significant differences were noted for erythrocyte sedimentation rate (p<0.02 between sexes. Among different age groups significant differences were found for total red blood cell count (p<0.001. Different body conditions have significant differences in red blood cell count, mean corpuscular volume and mean corpuscular hemoglobin (p<0.001. Pregnant and non-pregnant females differed significantly in their red blood cell count, mean corpuscular volume and mean corpuscular hemoglobin (p<0.001.

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

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    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.

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

    Science.gov (United States)

    Ravicini, Sara; Pastor, Josep; Hawley, Jennifer; Brewer, Melissa; Castro-López, Jorge; Beall, Melissa; Lappin, Michael R

    2016-01-01

    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. 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. 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). 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.

  4. Canine neosporosis in Hungary: screening for seroconversion of household, herding and stray dogs.

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    Hornok, S; Edelhofer, R; Fok, E; Berta, K; Fejes, P; Répási, A; Farkas, R

    2006-04-30

    In order to assess the seroprevalence of canine neosporosis 651 blood samples were collected from 586 household, 41 herding and 24 stray dogs, at small animal clinics in four large cities and other places of Hungary. Nineteen (2.9%) showed positivity in the IFAT with titres between 1:80 and 1:10240. Two dogs with high titres of antibodies to Neospora caninum had neuromuscular signs (imbalance, tremor) and a further one developed papulomatous, ulcerative and necrotizing dermatitis. There was no correlation between titers and age, sex, breed or keeping place. Although more male dogs had antibodies to N. caninum than females in case of both household and herding dogs, this association was not significant. No breed predisposition was observed. However, dogs with seroconversion were significantly more prevalent among rural (6%) than among urban dogs (1%), indicating that dogs in the countryside may have contact with or access to potentially infected offal from cattle and other intermediate hosts more frequently than those in large cities. Furthermore, significantly more herding dogs (29.3%) had antibodies to N. caninum than household dogs (1.2%), confirming the association between the occurrence of neosporosis and dog keeping on farms. The 12 dogs found seropositive among herding ones lived on 6 farms, on 5 of which seropositive cattle were also identified. This is the first report on the prevalence of N. caninum infection in dogs in Hungary.

  5. Contemporary Proton Therapy Systems Adequately Protect Patients from Exposure to Stray Radiation

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    Newhauser, Wayne D.; Fontenot, Jonas D.; Taddei, Phillip J.; Mirkovic, Dragan; Giebeler, Annelise; Zhang, Rui; Mahajan, Anita; Kornguth, David; Stovall, Marilyn; Yepes, Pablo; Woo, Shiao; Mohan, Radhe

    2009-03-01

    Proton beam therapy has provided safe and effective treatments for a variety of adult cancers. In recent years, there has been increasing interest in utilizing proton therapy for pediatric cancers because it allows better sparing of healthy tissues. Minimizing exposures of normal tissues is especially important in children because they are highly susceptible to consequential late effects, including the development of a radiogenic second cancer, which may occur years or even decades after treatment of the first cancer. While the dosimetric advantage of therapeutic proton beams is well understood, relatively little attention has been paid to the whole-body exposure to stray neutron radiation that is inherent in proton therapy. In this report, we review the physical processes that lead to neutron exposures, discuss the potential for mitigating these exposures using advanced proton beam delivery systems, and present a comparative analysis of predicted second cancer incidence following various external beam therapies. In addition, we discuss uncertainties in the relative biological effectiveness of neutrons for carcinogenesis and the impact that these uncertainties have on second-cancer risk predictions for survivors of adult and childhood cancer who receive proton therapy.

  6. The Zoonotic Risk of Ancylostoma ceylanicum Isolated from Stray Dogs and Cats in Guangzhou, South China

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    Yuanjia Liu

    2014-01-01

    Full Text Available Canine and feline hookworm infection is endemic in many countries with zoonotic transmission representing a potentially significant public health concern. However, there is limited data available on the zoonotic transmission of canine and feline hookworms in China. This study was conducted to evaluate the zoonotic risk of Ancylostoma ceylanicum isolated from stray dogs and cats in Guangzhou, south China. Primer pairs CAF/CAR were designed to amplify complete ITS sequences of obtained A. ceylanicum. The results were compared with fourteen ITS reference sequences of human-derived A. ceylanicum registered in GenBank, and phylogenetic trees were established by using NJ and ML methods. The sequence similarity of three dog-derived and five cat-derived A. ceylanicum with fourteen human-derived A. ceylanicum were 96.8%~100% and 97.8%~100%, respectively. Phylogenetic analysis placed A. ceylanicum isolated from dogs and cats in the same group with A. ceylanicum human isolates. Due to the ability of A. ceylanicum to cause a patent infection in humans, the zoonotic risk arising from dog and cat reservoirs to communities in this region should be determined.

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

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    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

  8. Geographic distribution of canine heartworm (Dirofilaria immitis infection in stray dogs of eastern Romania

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    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.

  9. Spirocercosis in stray dogs of Chittagong metropolitan area of Bangladesh: an epidemiological and pathological investigation

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    Muraduzzaman

    Full Text Available A total of sixty adult stray dogs (32 male and 28 female randomly captured from different locality of Chittagong metropolitan area were euthanized during the period of May 2010 to January 2011. The dogs were necropsized to observe the presence of Spirocerca lupi in their oesophagus producing characteristic nodular lesions. The associated haematological changes were also determined. Twenty four (40% of the captured dogs were positive (40.62 % male and 39.28 % female for spirocercosis having oesophageal nodular lesions. One to three broad based nodular lesions with an average diameter of 2.104±0.139 cm were observed in the caudal oesophagus of spirocerca positive dogs. Minimum 1 and maximum 12 worms found harboring in each nodule with an average number of 3.75± 0.686. The association between the oesophageal nodular lesions and body condition of the dogs was inconclusive and locationwise prevalence was also not clear. Anaemia was observed in infected dogs with significant reduction in ESR values and MCHC%. Leukocytosis, particularly neutrophilia was common in infected dogs in comparison to the noninfected. Histopathology revealed extensive fibrous tissue proliferation around the adult worms in most of the nodular lesions with large numbers of newly formed blood vessels resembling granulation tissues. A considerable degree of fibroplasia was evident with predominant accumulation of fibroblasts and irregular layers collagen fibers in mature nodules. Accumulation of large numbers of neutrophil was common in nodular lesions, whereas, infiltration of lymphoplasmacytic cells also found in some cases. One lesion showed evidence of fibrosarcoma characterized by proliferation of undifferentiated atypical fibroblasts having abnormal mitotic figures. [Vet. World 2011; 4(11.000: 485-491

  10. Geographic distribution of canine heartworm (Dirofilaria immitis) infection in stray dogs of eastern Romania.

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    Ciucă, Lavinia; Musella, Vincenzo; Miron, Liviu D; Maurelli, Maria Paola; Cringoli, Giuseppe; Bosco, Antonio; Rinaldi, Laura

    2016-11-21

    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.

  11. Description of Events Where African Buffaloes (Syncerus caffer) Strayed from the Endemic Foot-and-Mouth Disease Zone in South Africa, 1998-2008.

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    van Schalkwyk, O L; Knobel, D L; De Clercq, E M; De Pus, C; Hendrickx, G; Van den Bossche, P

    2016-06-01

    African buffaloes (Syncerus caffer) are reservoir hosts of Southern African Territories (SAT) foot-and-mouth disease (FMD) virus strains. In South Africa, infected buffaloes are found in the FMD-infected zone comprising the Kruger National Park (KNP) and its adjoining reserves. When these buffaloes stray into livestock areas, they pose a risk of FMD transmission to livestock. We assessed 645 records of stray buffalo events (3124 animals) from the FMD infected zone during 1998-2008 for (i) their temporal distribution, (ii) group size, (iii) age and gender composition, (iv) distance from the infected zone fence and (v) outcome reported for each event. A maximum entropy model was developed to evaluate spatial predictors of stray buffalo events and assess current disease control zones. Out of all buffaloes recorded straying, 38.5% escaped from the FMD infected zone during 2000/2001, following floods that caused extensive damage to wildlife fences. Escape patterns were not apparently influenced by season. The median size of stray groups was a single animal (IQR [1-2]). Adult animals predominated, comprising 90.4% (620/686) of the animals for which age was recorded. Of the 315 events with accurate spatial information, 204 (64.8%) were recorded within 1 km from the FMD infected zone. During late winter/spring (June-October), stray buffaloes were found significantly closer to the FMD infected zone (median = 0.3 km, IQR [0.1-0.6]). Less than 13% (40/315) of stray groups reached the FMD protection zone without vaccination, posing a higher risk of spreading FMD to these more susceptible livestock. Model outputs suggest that distance from the FMD infected zone, urban areas and permanent water sources contributed almost 85% to the spatial probability of stray buffalo events. Areas with a high probability for stray buffalo events were well covered by current disease control zones, although FMD risk mitigation could be improved by expanding the vaccination zone in certain areas

  12. Molecular detection of Hepatozoon spp. and Cytauxzoon sp. in domestic and stray cats from Madrid, Spain.

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    Díaz-Regañón, David; Villaescusa, Alejandra; Ayllón, Tania; Rodríguez-Franco, Fernando; Baneth, Gad; Calleja-Bueno, Lydia; García-Sancho, Mercedes; Agulla, Beatriz; Sainz, Ángel

    2017-03-13

    Different species of apicomplexan protozoans of the genera Hepatozoon and Cytauxzoon can infect domestic cats, but their epidemiology and clinical relevance are not fully understood. The aim of this study was to assess the molecular prevalence of Hepatozoon spp. and Cytauxzoon spp. and to identify associated risk factors and clinical and laboratory abnormalities in a population of cats from Madrid, Spain. Six hundred and forty-four client-owned and stray cats from Madrid, Spain, were included in this study. DNA samples were analyzed by two polymerase chain reaction (PCR) tests to detect a partial sequence of the 18S rRNA gene of Hepatozoon spp. and Cytauxzoon spp. In order to evaluate possible associations between infection by these protozoans and epidemiological or clinical parameters, data were collected related to: the season of sample collection, age, gender, spayed/neutered status, breed, living area, lifestyle, outdoor access, contact with other animals, prey on wild animals, history of tick or flea infestation, travel history, ectoparasiticide treatment, previous blood transfusion, previous tetracycline administration in the last 60 days, Feline Leukemia virus (FeLV) and Feline Immunodeficiency virus (FIV) status, positivity to other vector-borne diseases, the presence or absence of clinical signs and hematological or biochemical alterations. DNA of Hepatozoon spp. and Cytauxzoon sp. was amplified from the blood of 10 (1.6%) and 8 (1.2%) cats, respectively. Previous treatment with tetracyclines in the last 60 days, previous administration of blood transfusion, a decrease in haematocrit and an increase in creatinine were associated with Hepatozoon spp. infection. Cytauxzoon sp. infection was more frequent in samples collected during the winter months and in cats living in rural areas. This infection was associated with a FIV-positive status. Some of the cats that were positive for Hepatozoon spp. or Cytauxzoon sp. had been exposed to other vector

  13. Factors affecting the prevalence of mange-mite infestations in stray dogs of Yucatán, Mexico.

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    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).

  14. 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.

  15. Message Collision Avoidance Protocols for Detecting Stray Nodes in a Scuba Diving Group Using Ultrasonic Multi-Hop Message Communication

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    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.

  16. A descriptive and broadly applicable model of therapeutic and stray absorbed dose from 6 to 25 MV photon beams.

    Science.gov (United States)

    Schneider, Christopher W; Newhauser, Wayne D; Wilson, Lydia J; Schneider, Uwe; Kaderka, Robert; Miljanić, Saveta; Knežević, Željka; Stolarcyzk, Liliana; Durante, Marco; Harrison, Roger M

    2017-07-01

    To develop a simple model of therapeutic and stray absorbed dose for a variety of treatment machines and techniques without relying on proprietary machine-specific parameters. Dosimetry measurements conducted in this study and from the literature were used to develop an analytical model of absorbed dose from a variety of treatment machines and techniques in the 6 to 25 MV interval. A modified one-dimensional gamma-index analysis was performed to evaluate dosimetric accuracy of the model on an independent dataset consisting of measured dose profiles from seven treatment units spanning four manufacturers. The average difference between the calculated and measured absorbed dose values was 9.9% for those datasets on which the model was trained. Additionally, these results indicate that the model can provide accurate calculations of both therapeutic and stray radiation dose from a wide variety of radiotherapy units and techniques. We have developed a simple analytical model of absorbed dose from external beam radiotherapy treatments in the 6 to 25 MV beam energy range. The model has been tested on measured data from multiple treatment machines and techniques, and is broadly applicable to contemporary external beam radiation therapy. © 2017 American Association of Physicists in Medicine.

  17. Magnetic domain structures and stray fields of individual elongated magnetite grains revealed by magnetic force microscopy (MFM)

    DEFF Research Database (Denmark)

    Frandsen, Cathrine; Stipp, S. L. S.; McEnroe, S. A.

    2004-01-01

    In order to clarify the relationship between microscopic and macroscopic magnetic features of a rock, we applied magnetic force microscopy (MFM) as a local probe on a sample with an intense natural remanent magnetisation, a norite from Heskestad, Norway. We studied in detail seven magnetite (Fe3O...

  18. 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

  19. Stray Current-Induced Development of Cement-Based Microstructure in Water-Submerged, Ca(OH)2-Submerged and Sealed Conditions

    NARCIS (Netherlands)

    Susanto, A.; Koleva, D.A.; van Breugel, K.; van Beek, C.

    2017-01-01

    This work reports on the development of microstructural and mechanical properties of mortar cubes under the synergetic action of stray current and various environmental/curing conditions. The study refers to specimens cured for 24h only, followed by a 112 days period of partial or full submersion in

  20. 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

    2017-01-01

    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...

  1. Investigations of smooth surfaces by measuring the BRDF with a stray light sensor in comparison with PSD curves evaluated from topography of large AFM scans

    Science.gov (United States)

    Rothe, Hendrik; Hueser, Dorothee; Kasper, Andre; Rinder, Thomas

    1999-03-01

    For quality inspection of polished surfaces as applied in semiconductor and optical industry, various methods are used for a fast detection of microroughness, defects, and contaminations. With the aid of stray light sensors the intensity distribution of the reflected and scattered light, i.e. the BRDF, is measured. The probability distribution of values of a BRDF is parametrized to obtain a measure for roughness and for classes of defects. There is still need for justifying the choice of statistical moments to characterize and finally to classify different surfaces. Of course, a basic quantitative, i.e. metrological understanding of stray light sensors is necessary. The power spectrum of surface topographies sufficiently smooth to obey Rayleigh-Rice approximation is proportional to the BRDF. Therefore a comparison was only carried out with sample surfaces obeying this approximation. Defects and contaminations with lateral sizes smaller than the wavelength of the illuminating light employed in the stray light sensor, however, could not be analyzed within this investigation. We have measured the topography of large areas up to 600 micrometer X 100 micrometer with an AFM by patching several scans (up to 8) with overlap. BRDFs evaluated from AFM measurements agree well with BRDFs measured with a stray light sensor.

  2. 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.

  3. Microspatial genetic heterogeneity and gene flow in stray cats (Felis catus L.): a comparison of coat colour and microsatellite loci.

    Science.gov (United States)

    Say, Ludovic; Bonhomme, François; Desmarais, Eric; Pontier, Dominique

    2003-06-01

    We analysed levels of genetic differentiation between nine local urban colonies of stray cats using eight coat colour and nine microsatellite loci. Both types of markers revealed a strong differentiation between colonies (FST = 0.15 and 0.09 for coat colour and microsatellite loci, respectively). Three coat colour loci showed extreme levels of genetic differentiation comparatively to other loci and are strongly suspected to be under divergent selective pressures. Microsatellite loci showed significant heterozygote deficiency within colonies (FIS = 0.14), suggesting that coat colour loci are not appropriate to investigate genetic structure at a fine scale because coat colour allele frequencies are based on Hardy-Weinberg equilibrium. The reported pattern conformed to that predicted from the social structuring of cat colonies: aggressive exclusion of immigrants, inbreeding and very low dispersal rate.

  4. The prevalence and distribution of gastrointestinal parasites of stray and refuge dogs in four locations in India.

    Science.gov (United States)

    Traub, Rebecca J; Pednekar, Riddhi P; Cuttell, Leigh; Porter, Ronald B; Abd Megat Rani, Puteri Azaziah; Gatne, Mukulesh L

    2014-09-15

    A gastrointestinal parasite survey of 411 stray and refuge dogs sampled from four geographical and climactically distinct locations in India revealed these animals to represent a significant source of environmental contamination for parasites that pose a zoonotic risk to the public. Hookworms were the most commonly identified parasite in dogs in Sikkim (71.3%), Mumbai (48.8%) and Delhi (39.1%). In Ladakh, which experiences harsh extremes in climate, a competitive advantage was observed for parasites such as Sarcocystis spp. (44.2%), Taenia hydatigena (30.3%) and Echinococcus granulosus (2.3%) that utilise intermediate hosts for the completion of their life cycle. PCR identified Ancylostoma ceylanicum and Ancylostoma caninum to occur sympatrically, either as single or mixed infections in Sikkim (Northeast) and Mumbai (West). In Delhi, A. caninum was the only species identified in dogs, probably owing to its ability to evade unfavourable climatic conditions by undergoing arrested development in host tissue. The expansion of the known distribution of A. ceylanicum to the west, as far as Mumbai, justifies the renewed interest in this emerging zoonosis and advocates for its surveillance in future human parasite surveys. Of interest was the absence of Trichuris vulpis in dogs, in support of previous canine surveys in India. This study advocates the continuation of birth control programmes in stray dogs that will undoubtedly have spill-over effects on reducing the levels of environmental contamination with parasite stages. In particular, owners of pet animals exposed to these environments must be extra vigilant in ensuring their animals are regularly dewormed and maintaining strict standards of household and personal hygiene. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. 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

  6. Surrendered and Stray Dogs in Australia-Estimation of Numbers Entering Municipal Pounds, Shelters and Rescue Groups and Their Outcomes.

    Science.gov (United States)

    Chua, Diana; Rand, Jacquie; Morton, John

    2017-07-12

    There is no national system for monitoring numbers of dogs entering municipal council pounds and shelters in Australia, or their outcomes. This limits understanding of the surrendered and stray dog issue, and prevents the evaluation of management strategies. We aimed to estimate these in 2012-2013. Dog intake and outcome data were collected for municipal councils and animal welfare organizations using annual reports, publications, primary peer-reviewed journal articles, websites and direct correspondence. More comprehensive data were obtained for New South Wales, Victoria, South Australia and Australian Capital Territory, whereas it was necessary to impute some or all data for Western Australia, Northern Territory, Queensland and Tasmania, as data were incomplete/unavailable. A refined methodology was developed to address the numerous limitations of the available data. An estimated national total of 211,655 dog admissions (9.3 admissions/1000 residents) occurred in 2012-2013. Of these admissions, the numbers where the dog was reclaimed, rehomed or euthanized were estimated as 4.4, 2.9 and 1.9/1000 residents, respectively. Differences in outcomes were evident between states, and between municipal councils, welfare organizations and rescue groups. This study emphasizes the need for an ongoing standardized monitoring system with appropriate data routinely collected from all municipal councils, animal welfare organizations and rescue groups in Australia. Such a system would only require data that are easily collected by all relevant organizations and could be implemented at relatively low cost. This could facilitate ongoing evaluation of the magnitude of the surrendered and stray dog problem, and allow assessment of strategies aiming to reduce numbers of admissions and euthanasia.

  7. Surrendered and Stray Dogs in Australia—Estimation of Numbers Entering Municipal Pounds, Shelters and Rescue Groups and Their Outcomes

    Directory of Open Access Journals (Sweden)

    Diana Chua

    2017-07-01

    Full Text Available There is no national system for monitoring numbers of dogs entering municipal council pounds and shelters in Australia, or their outcomes. This limits understanding of the surrendered and stray dog issue, and prevents the evaluation of management strategies. We aimed to estimate these in 2012–2013. Dog intake and outcome data were collected for municipal councils and animal welfare organizations using annual reports, publications, primary peer-reviewed journal articles, websites and direct correspondence. More comprehensive data were obtained for New South Wales, Victoria, South Australia and Australian Capital Territory, whereas it was necessary to impute some or all data for Western Australia, Northern Territory, Queensland and Tasmania, as data were incomplete/unavailable. A refined methodology was developed to address the numerous limitations of the available data. An estimated national total of 211,655 dog admissions (9.3 admissions/1000 residents occurred in 2012–2013. Of these admissions, the numbers where the dog was reclaimed, rehomed or euthanized were estimated as 4.4, 2.9 and 1.9/1000 residents, respectively. Differences in outcomes were evident between states, and between municipal councils, welfare organizations and rescue groups. This study emphasizes the need for an ongoing standardized monitoring system with appropriate data routinely collected from all municipal councils, animal welfare organizations and rescue groups in Australia. Such a system would only require data that are easily collected by all relevant organizations and could be implemented at relatively low cost. This could facilitate ongoing evaluation of the magnitude of the surrendered and stray dog problem, and allow assessment of strategies aiming to reduce numbers of admissions and euthanasia.

  8. A low technology emanator treated with the volatile pyrethroid transfluthrin confers long term protection against outdoor biting vectors of lymphatic filariasis, arboviruses and malaria.

    Science.gov (United States)

    Ogoma, Sheila B; Mmando, Arnold S; Swai, Johnson K; Horstmann, Sebastian; Malone, David; Killeen, Gerry F

    2017-04-01

    The vapor phase of the volatile pyrethroid transfluthrin incapacitates mosquitoes and prevents them from feeding. Although existing emanator products for delivering volatile pyrethroids protect against outdoor mosquito bites, they are too short-lived to be practical or affordable for routine use in low-income settings. New transfluthrin emanators, comprised simply of treated hessian fabric strips, have recently proven highly protective against outdoor-biting vectors of lymphatic filariasis, arboviruses and malaria, but their full protective lifespan, minimum dose requirements, and range of protection have not previously been assessed. The effects of transfluthrin-treated hessian strips upon mosquito biting exposure of users and nearby non-users, as well as dependence of protection upon treatment dose, were measured outdoors in rural Tanzania using human landing catches (HLC). Strips treated with 10ml of transfluthrin prevented at least three quarters (p 90% protection against bites on warmer nights with higher evaporation rates, for at least one year. Strips treated with this high dose also reduced biting exposure of non-users at a distance of up to 5m from the strips for An. arabiensis (p protection to non-users against Culex spp. No evidence of increased risk for non-users, caused by diversion of mosquitoes to unprotected individuals, was found at any distance within an 80m radius. A dose of only 1ml provided equivalent protection to the 10ml dose against An. arabiensis, Culex spp. and Mansonia spp. mosquitoes over 6 months (p protection against several different pathogen-transmitting mosquito taxa that attack humans outdoors, where they are usually active and cannot be protected by bed nets or residual sprays with conventional, solid-phase insecticides.

  9. A low technology emanator treated with the volatile pyrethroid transfluthrin confers long term protection against outdoor biting vectors of lymphatic filariasis, arboviruses and malaria

    Science.gov (United States)

    Mmando, Arnold S.; Swai, Johnson K.; Horstmann, Sebastian; Malone, David; Killeen, Gerry F.

    2017-01-01

    Background The vapor phase of the volatile pyrethroid transfluthrin incapacitates mosquitoes and prevents them from feeding. Although existing emanator products for delivering volatile pyrethroids protect against outdoor mosquito bites, they are too short-lived to be practical or affordable for routine use in low-income settings. New transfluthrin emanators, comprised simply of treated hessian fabric strips, have recently proven highly protective against outdoor-biting vectors of lymphatic filariasis, arboviruses and malaria, but their full protective lifespan, minimum dose requirements, and range of protection have not previously been assessed. Methodology The effects of transfluthrin-treated hessian strips upon mosquito biting exposure of users and nearby non-users, as well as dependence of protection upon treatment dose, were measured outdoors in rural Tanzania using human landing catches (HLC). Principal findings Strips treated with 10ml of transfluthrin prevented at least three quarters (p 90% protection against bites on warmer nights with higher evaporation rates, for at least one year. Strips treated with this high dose also reduced biting exposure of non-users at a distance of up to 5m from the strips for An. arabiensis (p protection to non-users against Culex spp. No evidence of increased risk for non-users, caused by diversion of mosquitoes to unprotected individuals, was found at any distance within an 80m radius. A dose of only 1ml provided equivalent protection to the 10ml dose against An. arabiensis, Culex spp. and Mansonia spp. mosquitoes over 6 months (p protection against several different pathogen-transmitting mosquito taxa that attack humans outdoors, where they are usually active and cannot be protected by bed nets or residual sprays with conventional, solid-phase insecticides. PMID:28388682

  10. The Magnetized Brain : Working mechanisms for the effects of MRI-related magnetic fields on cognition, postural stability, and oculomotor function

    NARCIS (Netherlands)

    van Nierop, L.E.|info:eu-repo/dai/nl/323065384

    2015-01-01

    The growing popularity of MRI in clinical settings and the innovative applications in e.g. MRI guided surgery has resulted in more frequent, longer and higher levels of exposure to the stray magnetic fields for employees. Especially the use of stronger field strengths in MRI has been associated with

  11. Influences of extremely low frequency magnetic fields on mineral ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-11-05

    Nov 5, 2008 ... Exposure to extremely low frequency magnetic fields (ELF-MF) emanating from the generation, distribution, and utilization of electricity is widespread. The major debate in recent years has focused on the possibility that exposure to ELF-MF may result in adverse health consequences. The present study was ...

  12. Surrendered and Stray Dogs in Australia—Estimation of Numbers Entering Municipal Pounds, Shelters and Rescue Groups and Their Outcomes

    Science.gov (United States)

    Chua, Diana; Rand, Jacquie; Morton, John

    2017-01-01

    Simple Summary Analyses of comprehensive and accurate dog intake and outcome data in municipal pounds and shelters across states in Australia would provide an in-depth understanding of the surrendered and stray dog issue as well as facilitate effective evaluation of existing management strategies. Currently, there is a lack of comprehensive and reliable data at the federal, state and local government levels across public and private agencies. In this study, we developed a methodology to estimate the annual numbers of dog admissions in Australia, and to describe their outcomes. In 2012–2013, there were an estimated 9.3 dog admissions per 1000 residents (211,655 dog admissions). Of these admissions, 4.4 per 1000 residents were reclaimed (101,037 reclaimed), 2.9 per 1000 residents were rehomed (66,443 rehomed) and 1.9 per 1000 residents were euthanized (43,900 euthanized). An ongoing standardized monitoring system would enable Australia to evaluate management strategies to reduce numbers of dogs admitted and euthanized, and to benchmark its unwanted dog management policies and performance against comparable countries. Abstract There is no national system for monitoring numbers of dogs entering municipal council pounds and shelters in Australia, or their outcomes. This limits understanding of the surrendered and stray dog issue, and prevents the evaluation of management strategies. We aimed to estimate these in 2012–2013. Dog intake and outcome data were collected for municipal councils and animal welfare organizations using annual reports, publications, primary peer-reviewed journal articles, websites and direct correspondence. More comprehensive data were obtained for New South Wales, Victoria, South Australia and Australian Capital Territory, whereas it was necessary to impute some or all data for Western Australia, Northern Territory, Queensland and Tasmania, as data were incomplete/unavailable. A refined methodology was developed to address the numerous

  13. 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

  14. 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.

  15. First Report of Toxoplasma gondii, Dirofilaria immitis, and Chlamydia felis Infection in Stray and Companion Cats in Northeastern and Eastern China.

    Science.gov (United States)

    Kang, Yuan-Huan; Cong, Wei; Qin, Si-Yuan; Shan, Xiao-Feng; Gao, Yun-Hang; Wang, Chun-Feng; Qian, Ai-Dong

    2016-10-01

    Feline vector-borne diseases have increasingly become a focus of interest in recent years. Toxoplasma gondii, Dirofilaria immitis, and Chlamydia felis are common pathogens of cats that can affect humans among different countries all over the world. However, information about prevalence of T. gondii and C. felis is available in China, but information about coinfection of T. gondii, D. immitis, and C. felis in cats is limited. Thus, this study was conducted to estimate the prevalence of these pathogens' infection among stray and companion cats in northeastern and eastern China and identify the influence of age, gender, types, and regions on seropositivity. The circulating antigens of D. immitis and specific antibodies to T. gondii and C. felis were examined using kits commercially available. The overall prevalence of T. gondii, D. immitis, and C. felis was 15.43%, 1.93%, and 9.90%, respectively. Coinfection was common, and infection with both T. gondii and C. felis was the most common coinfection (22.32%). Stray cats have significantly higher seroprevalences than companion cats (p immitis, and C. felis infection in cats in northeastern and eastern China. The findings of this study reveal that T. gondii, D. immitis, and C. felis are prevalent in stray and companion cats in northeastern China, which provided baseline data for the effective prevention and control of these parasites' prevalence in these regions and other parts of China.

  16. Raiders of the Lost Art: A review of published evaluations of inpatient mental health care experiences emanating from the United Kingdom, Portugal, Canada, Switzerland, Germany and Australia.

    Science.gov (United States)

    Cutcliffe, John R; Santos, Jose Carlos; Kozel, Bernd; Taylor, Petrea; Lees, David

    2015-10-01

    Forming interpersonal therapeutic relationships with mental health Service Users remains a key aspect of the practice of Psychiatric/Mental Health nurses. Given the omnipresence of the concept within the relevant literature the reader could be forgiven for asking: why would Psychiatric/Mental Health nurses opine about something so basic, so ubiquitous and so central to the theory and practice of our discipline? While the authors could locate no substantive argument that refutes the role or value of such relationships, a sizable, growing and reasonably consistent body of work has emerged, which appears to indicate that this centrality and value is not necessarily reflected in many clinical practice settings. Accordingly, we draw on the published evaluations of mental health care emanating from the United Kingdom, Portugal, Canada, Switzerland, Germany and Australia, compare these findings and highlight similarities or/and congruence and discuss a range of issues arising out of the findings. Alas, the findings seem to depict a mental health care inpatient experience that is often devoid of warm therapeutic relationships, respectful interactions, information or choice about treatment and any kind of formal/informal 'talk therapy'. Instead such care experiences are personified by: coercion, disinterest, inhumane practices, custodial and controlling practitioners and a gross over use of pharmacological 'treatments'. © 2015 Australian College of Mental Health Nurses Inc.

  17. 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.

  18. Simulation of stray grain formation in Ni-base single crystal turbine blades fabricated by HRS and LMC techniques

    Directory of Open Access Journals (Sweden)

    Ya-feng Li

    2017-03-01

    Full Text Available The simulation models of the thermal and macrostructural evolutions during directional solidification of Ni-base single crystal (SX turbine blades under high rate solidification (HRS and liquid metal cooling (LMC have been constructed using ProCAST software, coupled with a 3D Cellular Automaton Finite Element (CAFE model. The models were used to investigate the tendencies of stray grain (SG formation in the platform region of turbine blades fabricated by HRS and LMC techniques. The results reveal that the LMC technique can prohibit SG formation by smoothing the concaved isotherm and in turn alleviating the undercooling in the platform ends to let the dendrites fill up the undercooled zone before SG nucleation. The simulation results agreed well with the experimental results, indicating that these models could be used to analyze the macrostructural evolution or to optimize process parameters to suppress SG formation. Using these models, the critical withdrawal rate for casting SX turbine blades without SG formation were determined to be around 75 μm·s-1 and 100 μm·s-1 for HRS and LMC respectively, suggesting that LMC can be used as an efficient technique in fabricating SX turbine blades without any SG defect formation.

  19. 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.

  20. First detection and molecular identification of Borrelia garinii spirochete from Ixodes ovatus tick ectoparasitized on stray cat in Taiwan.

    Directory of Open Access Journals (Sweden)

    Li-Lian Chao

    Full Text Available Borrelia garinii spirochete was detected for the first time in Ixodes ovatus tick ectoparasitized on stray cat in Taiwan. The genetic identity of this detected spirochete was determined by analyzing the gene sequence amplified by genospecies-specific polymerase chain reaction assays based on the 5S-23S intergenic spacer amplicon (rrf-rrl and outer surface protein A (ospA genes of B. burgdorferi sensu lato. Phylogenetic relationships were analyzed by comparing the sequences of rrf-rrl and ospA genes obtained from 27 strains of Borrelia spirochetes representing six genospecies of Borrelia. Seven major clades can be easily distinguished by neighbour-joining analysis and were congruent by maximum-parsimony method. Phylogenetic analysis based on rrf-rrl gene revealed that this detected spirochete (strain IO-TP-TW was genetically affiliated to the same clade with a high homogeneous sequences (96.7 to 98.1% similarity within the genospecies of B. garinii and can be discriminated from other genospecies of Borrelia spirochetes. Interspecies analysis based on the genetic distance values indicates a lower level (0.113 to the strains identified in I. ovatus collected from Japan and China. Intraspecies analysis also reveals a higher homogeneity (GD<0.005 between tick (strain IO-TP-TW and human (strain Bg-PP-TW1 isolates of B. garinii in Taiwan. This study provides the first evidence of B. garinii isolated and identified in an I. ovatus tick in Asia, and the higher homogeneity of B. garinii between tick and human strain may imply the risk of human infection by I. ovatus bite.

  1. Intestinal parasites and vector-borne pathogens in stray and free-roaming cats living in continental and insular Greece.

    Directory of Open Access Journals (Sweden)

    Anastasia Diakou

    2017-01-01

    Full Text Available This survey investigated the distribution of various intestinal parasites and vector-borne pathogens in stray and free-roaming cats living in four regions of Greece. A total number of one hundred and fifty cats living in three Islands (Crete, Mykonos and Skopelos and in Athens municipality was established as a realistic aim to be accomplished in the study areas. All cats were examined with different microscopic, serological and molecular assays aiming at evaluating the occurrence of intestinal parasites, and exposure to or presence of vector-borne infections. A total of 135 cats (90% was positive for one or more parasites and/or pathogens transmitted by ectoparasites. Forty-four (29.3% cats were positive for one single infection, while 91 (60.7% for more than one pathogen. A high number of (n. 53 multiple infections caused by feline intestinal and vector-borne agents including at least one zoonotic pathogen was detected. Among them, the most frequently recorded helminths were roundworms (Toxocara cati, 24% and Dipylidium caninum (2%, while a high number of examined animals (58.8% had seroreaction for Bartonella spp., followed by Rickettsia spp. (43.2% and Leishmania infantum (6.1%. DNA-based assays revealed the zoonotic arthropod-borne organisms Bartonella henselae, Bartonella clarridgeiae, Rickettsia spp., and L. infantum. These results show that free-ranging cats living in areas of Greece under examination may be exposed to a plethora of internal parasites and vector-borne pathogens, some of them potentially able to infect humans. Therefore, epidemiological vigilance and appropriate control measures are crucial for the prevention and control of these infections and to minimize the risk of infection for people.

  2. Angler harvest, hatchery return, and tributary stray rates of recycled adult summer steelhead Oncorhynchus mykiss in the Cowlitz River, Washington

    Science.gov (United States)

    Kock, Tobias J.; Perry, Russell W.; Gleizes, Chris; Dammers, Wolf; Liedtke, Theresa L.

    2016-01-01

    Hatchery ‘recycling’ programs have been used to increase angling opportunities by re-releasing fish into a river after they returned to a hatchery or fish trap. Recycling is intended to increase opportunities for fishermen, but this strategy could affect wild fish populations if some recycled fish remain in the river and interact with wild fish populations. To quantify hatchery return and angler harvest rates of recycled steelhead, we conducted a 2-year study on the Cowlitz River, Washington. A total of 1051 steelhead were recycled, including 218 fish that were radio-tagged. Fates of recycled steelhead were similar between years: 48.4% returned to the hatchery, 19.2% were reported captured by anglers, and 32.4% remained in the river. A multistate model quantified the effects of covariates on hatchery return and angler harvest rates, which were positively affected by river discharge and negatively affected by time since release. However, hatchery return rates increased and angler harvest rates decreased during periods of increasing discharge. A total of 21.1% (46 fish) of the radio-tagged steelhead failed to return to the hatchery or be reported by anglers, but nearly half of those fish (20 fish) appeared to be harvested and not reported. The remaining tagged fish (11.9% of the radio-tagged population) were monitored into the spawning period, but only five fish (2.3% of the radio-tagged population) entered tributaries where wild steelhead spawning occurs. Future research focused on straying behaviour, and spawning success of recycled steelhead may further advance the understanding of the effects of recycling as a management strategy.

  3. Infection rate and genetic diversity of Giardia duodenalis in pet and stray dogs in Henan Province, China.

    Science.gov (United States)

    Qi, Meng; Dong, Haiju; Wang, Rongjun; Li, Junqiang; Zhao, Jinfeng; Zhang, Longxian; Luo, Jianxun

    2016-04-01

    Giardia duodenalis is an important protozoan parasite that is known to be zoonotic. To assess the potential zoonotic transmission of giardiasis from dogs and to identify genetic diversity of G. duodenalis in dog populations, we examined the infection rate and genotypes of G. duodenalis in both pet dogs (from pet dog farms, pet shops, pet hospitals, pet markets) and stray dogs of different ages in Henan Province, China. A total of 940 fresh fecal specimens were collected from 2007 to 2013 in Henan Province. The overall infection rate of G. duodenalis was 14.3% (134/940) as determined by microscopy, with the highest infection rate (17.3%) observed in dogs from shelters. Young dogs were more likely to be infected with G. duodenalis than adult dogs, and G. duodenalis cysts were found more frequently in diarrheic dogs. All G. duodenalis-positive isolates were characterized at the triose phosphate isomerase (tpi), glutamate dehydrogenase (gdh), and β-giardin (bg) loci, and 37, 51, and 48 sequences were obtained, respectively. The dog-specific assemblages C and D were identified using multi-locus sequence analysis. Six novel sequences of the tpi locus, one novel sequence of the gdh locus and two novel sequences of the bg locus were detected among the G. duodenalis assemblage C isolates, while two novel sequences of the gdh locus were found among the G. duodenalis assemblage D isolates. Our data indicate that G. duodenalis is a common parasite and cause of diarrheal disease in dogs in Henan Province. However, there was no evidence for zoonotic G. duodenalis assemblages in the study population. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  4. Sensitivity of Dobson and Brewer Umkehr ozone profile retrievals to ozone cross-sections and stray light effects

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    L. Flynn

    2011-09-01

    Full Text Available Remote sounding methods are used to derive ozone profile and column information from various ground-based and satellite measurements. Vertical ozone profiles measured in Dobson units (DU are currently retrieved based on laboratory measurements of the ozone absorption cross-section spectrum between 270 and 400 nm published in 1985 by Bass and Paur (BP. Recently, the US National Aeronautics and Space Administration (NASA and the European Space Agency (ESA proposed using the set of ozone cross-section measurements made at the Daumont laboratory in 1992 (BDM for revising the Aura Ozone Monitoring Instrument (OMI and Global Ozone Monitoring Experiment (GOME satellite ozone profiles and total ozone column retrievals. Dobson Umkehr zenith sky data have been collected by NOAA ground-based stations at Boulder, CO (BDR and Mauna Loa Observatory, HI (MLO since the 1980s. The UMK04 algorithm is based on the BP ozone cross-section data. It is currently used for all Dobson Umkehr data processing submitted to the World Ozone and Ultraviolet radiation Data Centre (WOUDC under the Global Atmosphere Watch (GAW program of the World Meteorological Organization (WMO. Ozone profiles are also retrieved from measurements by the Mark IV Brewers operated by the NOAA-EPA Brewer Spectrophotometer UV and Ozone Network (NEUBrew using a modified UMK04 algorithm (O3BUmkehr v.2.6, Martin Stanek. This paper describes the sensitivity of the Umkehr retrievals with respect to the proposed ozone cross-section changes. It is found that the ozone cross-section choice only minimally (within the retrieval accuracy affects the Dobson and the Brewer Umkehr retrievals. On the other hand, significantly larger errors were found in the MLO and Boulder Umkehr ozone data (−8 and +5% bias in stratosphere and troposphere respectively when the out-of-band (OOB stray light contribution to the Umkehr measurement is not taken into account (correction is currently not included in the UMK04. The

  5. Prevalence of haemoparasites in pet, working and stray dogs of Assam and North-East India: A hospital based study

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    K. Bhattacharjee

    2013-10-01

    Full Text Available Aim:This research work is aimed to find out the prevalence of haemoparasitic infections in different categories of dogs.Materials and Methods: Out of 2104 dogs registered in the Teaching Veterinary Clinical Complex of the College ofVeterinary Science, Khanapara, Guwahati during January 2009 to December 2010, blood of 424 cases suspected forhaemoparasites on the basis of clinical history were microscopically examined in wet blood film and giemsa stained bloodsmears.Results: The prevalence was 57.31% in the hospital population comprising pet (58.03% and working (54.54% dogs and63.64% in stray dog population. A total of 7 species viz. Babesia gibsoni (47.16%, Ehrlichia (Anaplasma platys (8.49%,Dirofilaria immitis (2.83%, Ehrlichia canis (2.12%, Babesia canis (1.41%, Hepatozoon canis (1.41% and Ehrlichiaewingii (0.47% in single or mixed infections were recorded. B. gibsoni was found to be most predominant haemoprotozoanspecies. However, B. canis, the large form of Babesia was detected in very few dogs. Similarly, inclusion of E. platys insideblood platelets, although rare in occurrence, was more easily detectable than that of E. canis inside the monocytes andlymphocytes. Infection with D. immitis in pet dogs (2.38% was comparatively lower than in working dogs (4.54% and foundin single and mixed infections with B. gibsoni, B. canis and E. platys. Hepatozoon canis was recorded in 6 hospital dogs eitherin single or mixed infection with B. gibsoni and E. platys. Six species of haemoparasites namely B. gibsoni (47.72%, D.immitis (27.27%, E. platys (4.54%, E. canis (2.27%, E. ewingii (2.27% and H. canis (2.27% were detected in blood ofstray dogs. Trypanosoma evansi as recorded in dogs from other parts of the country was not detected in this study.Conclusion: Present findings led to a significant conclusion that Assam and adjoining states of North East region of India arehighly enzootic for the vector borne haemoparasites of dog.

  6. PENGARUH MODEL PEMBELAJARAN KOOPERATIF TIPE TWO STAY TWO STRAY (TSTS TERHADAP HASIL BELAJAR SISWA PADA MATERI LISTRIK DINAMIS PADA SISWA SMA

    Directory of Open Access Journals (Sweden)

    Ida Wahyuni

    2014-06-01

    Full Text Available Penelitian ini bertujuan untuk mengetahui pengaruh penggunaan model pembelajaran Kooperatif Tipe Two Stay Two Stray terhadap hasil belajar siswa pada materi Listrik Dinamis di kelas X SMA. Jenis penelitian ini adalah quasi eksperimen dengan desain penelitian adalah Two Group Pretest postest Design. Populasi penelitian seluruh siswa kelas X SMA Negeri 3 Tebing Tinggi yang terdiri 9 kelas. Sampel penelitian diambil 2 kelas yang ditentukan dengan teknik cluster random sampling yaitu kelas X-9 sebagai kelas eksperimen dan kelas X-8 sebagai kelas kontrol. Untuk menguji hipotesis digunakan uji t setelah uji prasyarat dilakukan yaitu uji normalitas dan uji homogenitas. Dari hasil penelitian nilai rata-rata pretes kelas eksperimen adalah 36,30 dan kelas kontrol 27,90. Untuk data pretes, pada pengujian normalitas di kelas eksperimen dengan L hitung = 0,1378 dan L = 0,1730, kelas kontrol dengan L = 0,1368 dan Ltabel = 0,1730, diperoleh L hitung t tabel hitung yaitu 2,326 > 2,006 dengan  = 0,05 dan dk = 54, maka Ha diterima yang berarti ada perbedaan akibat pengaruh model pembelajaran Kooperatif Tipe Two Stay Two Stray dengan model pembelajaran konvensional terhadap hasil belajar siswa pada materi Listrik Dinamis di kelas X SMA Negeri 3 Tebing Tinggi T.P 2012/2013.

  7. Vector-Borne Diseases in Stray Dogs in Peninsular Malaysia and Molecular Detection of Anaplasma and Ehrlichia spp. from Rhipicephalus sanguineus (Acari: Ixodidae) Ticks.

    Science.gov (United States)

    Koh, Fui Xian; Panchadcharam, Chandrawathani; Tay, Sun Tee

    2016-01-01

    Little data are available on the prevalence and transmission of vector-borne diseases in stray dogs in Peninsular Malaysia. This study was designed to determine the occurrence of vector-borne pathogens in Malaysian stray dogs using serological and molecular approaches. In total, 48 dog blood samples were subjected to serological analysis using SNAP 4Dx kit (IDEXX Laboratories, Westbrook, ME). The presence of Ehrlichia and Anaplasma DNA in the dog blood samples and Rhipicephalus sanguineus (Latreille) ticks was detected using nested polymerase chain reaction assays. Positive serological findings against Ehrlichia canis and Anaplasma phagocytophilum were obtained in 17 (39.5%) and four (9.3%) of 43 dog samples, respectively. None of the dog blood samples were positive for Borrelia burgdorferi and Dirofilaria immitis. DNA of E. canis and A. phagocytophilum was detected in 12 (25.5%) and two (4.3%) of 47 dog blood samples, and 17 (51.5%) and one (3.0%) of 33 R. sanguineus ticks, respectively. Additionally, DNA of Ehrlichia spp. closely related to Ehrlichia chaffeensis was detected in two (6.1%) R. sanguineus ticks. This study highlights the prevalence of anaplasmosis and ehrlichiosis in dogs in Malaysia. Due to the zoonotic potential of Ehrlichia and Anaplasma spp., appropriate measures should be instituted for prevention and control of vector-borne diseases in dogs. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Electrosmog - effects of electrotechnical fields on the human organism; Elektrosmog - Wirkungen elektrotechnischer Felder auf den Menschen

    Energy Technology Data Exchange (ETDEWEB)

    David, E. [Forschungsstelle fuer Elektropathologie, Physiologischen Inst., Univ. Witten/Herdecke (Germany); Palic, M.

    1994-02-01

    The present article gives an overview of the currently known basic effects of fields emanating from electrical devices and plants on the human organisation and explains the defined limit values. (orig./MG) [Deutsch] Es wird ein Ueberblick ueber die wesentlichen Wirkungen der von elektrischen Anlagen und Geraeten ausgehenden Felder auf den menschlichen Organismus gegeben sowie die Grenzwerte erlaeutert. (orig./MG)

  9. Measurements and simulation of induced activity at the CERN-EU high- energy reference field facility

    CERN Document Server

    Brugger, M; Mitaroff, W A; Roesler, S

    2003-01-01

    Samples of aluminum, copper, stainless steel, iron, boron nitride, carbon composite and water were irradiated by the stray radiation field produced by interactions of high-energy hadrons in a copper target. The specific activity induced in the samples was measured by gamma spectrometry. In addition, the isotope production in the samples was calculated with detailed Monte-Carlo simulations using the FLUKA code. Results of the simulation are in reasonable agreement with the measured activities. 7 Refs.

  10. 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.

  11. 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.

  12. Tick-borne agents in domesticated and stray cats from the city of Campo Grande, state of Mato Grosso do Sul, midwestern Brazil.

    Science.gov (United States)

    André, Marcos Rogério; Herrera, Heitor Miraglia; Fernandes, Simone de Jesus; de Sousa, Keyla Cartens Marques; Gonçalves, Luiz Ricardo; Domingos, Iara Helena; de Macedo, Gabriel Carvalho; Machado, Rosangela Zacarias

    2015-09-01

    Anaplasmataceae agents, piroplasmids and Hepatozoon spp. have emerged as important pathogens among domestic and wild felines. The present work aimed to detect the presence of species belonging to the Anaplasmataceae family, piroplasmas and Hepatozoon spp. DNA in blood samples of domesticated and stray cats in the city of Campo Grande, state of Mato Grosso do Sul, midwestern Brazil. Between January and April 2013, whole blood samples were collected from 151 cats (54 males, 95 females and two without gender registration) in the city of Campo Grande, state of Mato Grosso do Sul, Brazil. DNA extracted from cat blood samples was submitted to conventional PCR assays for Theileria/Babesia/Cytauxzoon spp. (18S rRNA, ITS-1), Ehrlichia spp. (16S rRNA, dsb, groESL), Anaplasma spp. (16S rRNA, groESL) and Hepatozoon spp. (18S rRNA) followed by phylogenetic reconstructions. Out of 151 sampled cats, 13 (8.5%) were positive for Ehrlichia spp. closely related to Ehrlichia canis, 1 (0.66%) for Hepatozoon spp. closely related to Hepatozoon americanum and Hepatozoon spp. isolate from a wild felid, 1 (0.66%) for Cytauxzoon sp. closely related do Cytauxzoon felis, and 18 (11.9%) for Babesia/Theileria (one sequence was closely related to Babesia bigemina, eight for Babesia vogeli, five to Theileria spp. from ruminants [Theileria ovis, Theileria lestoquardi] and four to Theileria sp. recently detected in a cat). The present study showed that Ehrlichia spp., piroplasmids (B. vogeli, Theileria spp. and Cytauxzoon spp.) and, more rarely, Hepatozoon spp. circulate among stray and domesticated cats in the city of Campo Grande, state of Mato Grosso do Sul, midwestern Brazil. Copyright © 2015 Elsevier GmbH. All rights reserved.

  13. Calibration of a degassing-emanation line for 222Rn determination in seawater samples; Calibracao de uma linha de emanacao para determinacao de {sup 222}Rn em amostras de agua do mar

    Energy Technology Data Exchange (ETDEWEB)

    Farias, Luciana Aparecida

    2002-07-01

    The purpose of this study is to calibrate a degassing-emanation line and to determine {sup 222}Rn and {sup 226}Ra activity concentrations in seawater samples. This methodology, also called Lucas method, consists in the extraction of radon (originally dissolved in seawater), collection of the gas in a liquid nitrogen cold trap and transfer from the trap to an alpha scintillation cell. Total extraction efficiencies of the 4 degassing-emanation systems were determined by measuring {sup 226}Ra reference solutions. The efficiencies obtained for these 4 systems varied from 21 % to 62%. This work also presents preliminary results of a study carried out in a series of small embayements of Ubatuba, Sao Paulo State-Brazil: Flamengo Bay, Fortaleza Bay, Mar Virado Bay and Ubatuba Bay. Concentration of Rn in excess varied from 0,011 to 0,317 Bq/L for Flamengo Bay, from 0,009 to 0,130 Bq/L for Fortaleza Bay, from 0,018 to 0,050 Bq/L for Mar Virado Bay and from 0,004 to 0,120 Bq/L for Ubatuba Bay. The results obtained for the concentration of {sup 222}Rn in excess in a transect at Flamengo Bay varied from 0,002 to 0,036 Bq/L. Higher concentrations of {sup 222}Rn in excess were obtained in Flamengo Bay, Fortaleza Bay and Ubatuba bay. It was also observed that the concentration of {sup 222}Rn in excess increases with depth, as expected. (author)

  14. Hystological confirmation of Opisthorchis felineus in two stray cats on ‘Isola Maggiore’ (Trasimeno Lake, Perugia, Italy: the epidemiological chain of human opisthorchiasis is almost complete in this middle Italy lake

    Directory of Open Access Journals (Sweden)

    Daniele Crotti

    2010-09-01

    Full Text Available Over the past five years have been described, in Umbria, the first human cases of infestation with Opistorchis felineus, as well as detect the presence of this fluke eggs in the feces of Digenea stray seeds or stray cats on the island of Maggiore Lake Trasimeno (Umbria in central Italy. Previous research metacercariae in fish caught in this lake and the recovery of the shellfish B. leach into the lake area have been rather insignificant.This work confirms the presence of eggs of O. felineus in 33.3% of cat litter and, most importantly, it shows active infestation in two cats found dead on that island, anatomical lesions - histopathological opisthorchiasi and consistent with the observation of the presence of adult worm with eggs is in intrahepatic bile home that when pancreatic O. felineus.

  15. PENERAPAN METODE TSTS (TWO STAY TWO STRAY UNTUK MENINGKATKAN KEAKTIFAN DAN HASIL BELAJAR MELAKUKAN PERBAIKAN ENGINE BERIKUT KOMPONEN-KOMPONENNYA SISWA KELAS X JURUSAN TEKNIK SEPEDA MOTOR SMK TAMANSISWA NAGGULAN 2015/2016

    Directory of Open Access Journals (Sweden)

    Patrisius Meon Herin

    2017-06-01

    The purpose of this research is knowing the process of implementing the method TSTS (two stay two stray in an effort to enhance the liveliness and results of learning and determine whether the implementation of the method TSTS (two stay two stray can enhance the liveliness and results of learning especially on learning improvement of engine and its components. This research is Classroom Action Research. Subject in this research were students of class X Motorcycle Engineering SMK Tamansiswa Nanggulan Kulon Progo, which has 21 students. The object of this research is the implementation process of the liveliness and the results obtained from the method TSTS on lesson improvement of engine and its components. Data collection techniques in this research conducted by observation and testing techniques. Data analysis technique implementation is done by qualitative descriptive . The results showed that after the applied method TSTS, liveliness and results of learning in lesson improvements engine and its components are increased so that the results of learning of students also increased. Results liveliness pre-test is 42% and after the action the cycle I 47%, the cycle II 65%, and the cycle III 76%. The percentage of whose value increases the cycle I 71%, the cycle II 75%, and the cycle III 85%. The response of students to the method TSTS (two stay two stray was excellent. Looks percentage of every aspect with very high qualifications

  16. Campylobacter intestinal carriage among stray and pet dogs Disseminação de Campylobacter entre cães vadios e de estimação

    Directory of Open Access Journals (Sweden)

    Heriberto Fernández

    1991-12-01

    Full Text Available The natural distribution of thermotolerant Campylobacter sp. in dogs (150 stray animals and 64 pets was studied. Campylobacters were more frequently isolated (pFoi estudada a distribuição natural de espécies termotolerantes de Campylobacter em 159 cães vadios e em 64 cães de companhia em confinamento permanente. Espécies de Campylobacter foram isoladas mais freqüentemente (p<0,01 dos cães vadios (51,3% do que dos cães de companhia (21,9%. Todos os biotipos descritos por Lior para C. jejuni e C. coli foram encontrados entre as amostras isoladas dos cães vadios. Nas amostras isoladas dos cães mantidos em confmamento permanente somente foram encontrados os biotipos I e II de C. jejuni e o biotipo II do C. coli. Salienta-se a necessidade de realizar outros estudos para estabelecer a relação entre as condições de saneamento ambiental e a disseminação das espécies termotolerantes de Campylobacter.

  17. Seroprevalence of feline immunodeficiency virus, feline leukaemia virus and Toxoplasma gondii in stray cat colonies in northern Italy and correlation with clinical and laboratory data.

    Science.gov (United States)

    Spada, Eva; Proverbio, Daniela; della Pepa, Alessandra; Perego, Roberta; Baggiani, Luciana; DeGiorgi, Giada Bagnagatti; Domenichini, Giulia; Ferro, Elisabetta; Cremonesi, Fausto

    2012-06-01

    Stray cat colonies in urban and rural areas of Lombardy, northern Italy, were surveyed for seroprevalence of feline immunodeficiency virus (FIV) antibodies, feline leukaemia virus (FeLV) antigen and Toxoplasma gondii IgG. Of 316 cats tested, 6.6% were positive for FIV and 3.8% were positive for FeLV infection; 203 cats were tested for T gondii IgG antibodies and a prevalence of 30.5% was detected. Statistical analysis tested the influence of provenience, age, gender, health status and laboratory results on seroprevalence and found male gender and adult age were risk factors for FIV infection. FIV-infected cats were more likely to have a decreased red blood cell count than FIV seronegative cats. No predictors were significantly associated with FeLV and T gondii seropositivity. Colony cats in this study posed a limited risk for retrovirus infection to pet cats allowed outdoors, whereas toxoplasmosis exposure was comparable with the worldwide data.

  18. Feline immunodeficiency virus, feline leukemia virus and Toxoplasma gondii in stray and household cats in Kerman-Iran: seroprevalence and correlation with clinical and laboratory findings.

    Science.gov (United States)

    Akhtardanesh, Baharak; Ziaali, Naser; Sharifi, Hamid; Rezaei, Shirin

    2010-10-01

    This study was carried out to determine the seroprevalence of feline leukemia virus (FeLV), feline immunodeficiency virus (FIV) and Toxoplasma gondii (T. gondii) infection among stray and owned cats in southeastern Iran and to identify the influence of age, sex, lifestyle, health status, and laboratory findings on seropositivity. The overall infection rate for FIV, FeLV, and T. gondii was 19.2%, 14.2%, and 32.1% respectively. Results of the multivariate logistic regression analysis showed that old adults more likely to be seropositive than juveniles for FIV, FeLV, and T. gondii (adjusted odds ratios [ORs], 1.84, 1.56, and 2.57 respectively). Anemic and diseased cats ([ORs], 6.62 and 0.9) were at a greater risk of testing positive for FeLV. Male cats were 4.91 times as likely to have FIV as were female and hyperglobulinemia was significantly more prevalent in FIV-infected cats ([ORs], 3.4). In conclusion, FIV and FeLV seem to be endemic in Iran and retroviral-associated immunosuppression may be a risk factor for active toxoplasmosis in infected cats. 2010 Elsevier Ltd. All rights reserved.

  19. Prevalence of feline leukaemia virus and antibodies to feline immunodeficiency virus and feline coronavirus in stray cats sent to an RSPCA hospital.

    Science.gov (United States)

    Muirden, A

    2002-05-18

    A total of 517 stray cats at an RSPCA veterinary hospital were tested for feline leukaemia virus (FeLV), feline coronavirus (FCoV) and feline immunodeficiency virus (FIV). The prevalence of FeLV was 3.5 per cent in all the cats, 1.4 per cent in healthy cats and 6.9 per cent in sick cats. FeLV positivity was associated only with disease of non-traumatic origin. Antibodies to FCoV were present in 22.4 per cent of the cats, and their prevalence was significantly higher in cats over two years old and in feral/semiferal cats. The prevalence of antibodies to FIV was 10.4 per cent in all the cats, 4.9 per cent in healthy cats and 16.7 per cent in sick cats. The prevalence of FIV antibodies was significantly higher in entire males and neutered males than in females, in cats over two years old compared with younger cats, and in cats suffering disease of non-traumatic origin rather than in healthy cats or cats suffering only from trauma. Sex, age and health status were each independently highly associated with FIV antibodies.

  20. Measurement of Wave Electric Fields in Plasmas by Electro-Optic Probe

    CERN Document Server

    Nishiura, M; Mushiake, T; Kawazura, Y; Osawa, R; Fujinami, K; Yano, Y; Saitoh, H; Yamasaki, M; Kashyap, A; Takahashi, N; Nakatsuka, M; Fukuyama, A

    2016-01-01

    Electric field measurement in plasmas permits quantitative comparison between the experiment and the simulation in this study. An electro-optic (EO) sensor based on Pockels effect is demonstrated to measure wave electric fields in the laboratory magnetosphere of the RT-1 device with high frequency heating sources. This system gives the merits that electric field measurements can detect electrostatic waves separated clearly from wave magnetic fields, and that the sensor head is separated electrically from strong stray fields in circumference. The electromagnetic waves are excited at the double loop antenna for ion heating in electron cyclotron heated plasmas. In the air, the measured wave electric fields are in good absolute agreement with those predicted by the TASK/WF2 code. In inhomogeneous plasmas, the wave electric fields in the peripheral region are enhanced compared with the simulated electric fields. The potential oscillation of the antenna is one of the possible reason to explain the experimental resu...

  1. 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.

  2. Pulsed neutron fields measurements around a synchrotron storage ring

    Science.gov (United States)

    Caresana, Marco; Ballerini, Marcello; Ulfbeck, David Garf; Hertel, Niels; Manessi, Giacomo Paolo; Søgaard, Carsten

    2017-09-01

    A measurement campaign was performed for characterizing the neutron ambient dose equivalent, H*(10), in selected positions at ISA, Aarhus, Denmark, around the ASTRID and ASTRID2 storage rings. The neutron stray radiation field is characterized here by very intense radiation bursts with a low repetition rate, which result in a comparatively low average H*(10) rate. As a consequence, devices specifically conceived for operating in pulsed neutron fields must be employed for efficiently measuring in this radiation environment, in order to avoid severe underestimations of the H*(10) rate. The measurements were performed with the ELSE NUCLEAR LUPIN 5401 BF3-NP rem counter, a detector characterized by an innovative working principle that is not affected by dead time losses. This allowed characterizing both the H*(10) and the time structure of the radiation field in the pre-selected positions.

  3. Instrument intercomparison in the high-energy mixed field at the CERN-EU reference field (CERF) facility

    CERN Document Server

    Caresana, Marco; Manessi, Giacomo; Ott, Klaus; Scherpelz, Robert; Silari, Marco

    2014-01-01

    This paper discusses an intercomparison campaign performed in the mixed radiation field at the CERN-EU (CERF) reference field facility. Various instruments were employed: conventional and extended-range rem counters including a novel instrument called LUPIN, a bubble detector using an active counting system (ABC 1260) and two tissue-equivalent proportional counters (TEPCs). The results show that the extended range instruments agree well within their uncertainties and within 1σ with the H*(10) FLUKA value. The conventional rem counters are in good agreement within their uncertainties and underestimate H*(10) as measured by the extended range instruments and as predicted by FLUKA. The TEPCs slightly overestimate the FLUKA value but they are anyhow consistent with it when taking the comparatively large total uncertainties into account, and indicate that the non-neutron part of the stray field accounts for ∼30 % of the total H*(10).

  4. Serological and molecular prevalence of selected canine vector borne pathogens in blood donor candidates, clinically healthy volunteers, and stray dogs in North Carolina.

    Science.gov (United States)

    Balakrishnan, Nandhakumar; Musulin, Sarah; Varanat, Mrudula; Bradley, Julie M; Breitschwerdt, Edward B

    2014-03-24

    Canine vector borne diseases (CVBDs) comprise illnesses caused by a spectrum of pathogens that are transmitted by arthropod vectors. Some dogs have persistent infections without apparent clinical, hematological or biochemical abnormalities, whereas other dogs develop acute illnesses, persistent subclinical infections, or chronic debilitating diseases. The primary objective of this study was to screen healthy dogs for serological and molecular evidence of regionally important CVBDs. Clinically healthy dogs (n = 118), comprising three different groups: Gp I blood donor candidates (n = 47), Gp II healthy dog volunteers (n = 50), and Gp III stray dogs (n = 21) were included in the study. Serum and ethylenediamine tetraacetic acid (EDTA) anti-coagulated blood specimens collected from each dog were tested for CVBD pathogens. Of the 118 dogs tested, 97 (82%) dogs had been exposed to or were infected with one or more CVBD pathogens. By IFA testing, 9% of Gp I, 42% of Gp II and 19% of Gp III dogs were seroreactive to one or more CVBD pathogens. Using the SNAP 4DX assay, Gp I dogs were seronegative for Anaplasma spp., Ehrlichia spp., and B. burgdorferi (Lyme disease) antibodies and D. immitis antigen. In Gp II, 8 dogs were Ehrlichia spp. seroreactive, 2 were infected with D. immitis and 1 was B. burgdorferi (Lyme disease) seroreactive. In Gp III, 6 dogs were infected with D. immitis and 4 were Ehrlichia spp. seroreactive. Using the BAPGM diagnostic platform, Bartonella DNA was PCR amplified and sequenced from 19% of Gp I, 20% of Gp II and 10% of Gp III dogs. Using PCR and DNA sequencing, 6% of Gps I and II and 19% of Gp III dogs were infected with other CVBD pathogens. The development and validation of specific diagnostic testing modalities has facilitated more accurate detection of CVBDs. Once identified, exposure to vectors should be limited and flea and tick prevention enforced.

  5. Pathological conditions of the reproductive organs of male stray dogs in the tropics: prevalence, risk factors, morphological findings and testosterone concentrations.

    Science.gov (United States)

    Ortega-Pacheco, A; Rodríguez-Buenfil, J C; Segura-Correa, J C; Bolio-Gonzalez, M E; Jiménez-Coello, M; Linde Forsberg, C

    2006-10-01

    The objective of this study was to estimate the prevalence of and risk factors for pathological conditions of the reproductive organs in stray dogs under tropical conditions. Three hundred and eighteen dogs were examined post-mortem in the period from 1 July 2002 to 30 June 2003. Before killing, a blood sample (from the cephalic vein) for testosterone assay was taken. Pathological conditions of the reproductive organs were found in 135 of the dogs (42.5%) and in 175 of the testes (64.8%). The most frequent pathologies found were testicular degeneration, cryptorchidism, testicular hypoplasia and testicular tumours (in 15.1%, 6.6%, 6.6% and 5.4% of the dogs and 15.1, 4.6, 6.0 and 3.5 of the testes, respectively). Transmissible venereal tumour (TVT) was seen in 5.4% of the dogs. Testicular degeneration was more common in old dogs and underweight dogs (p dogs. Age was another important factor for the development of testicular tumours (p dogs with advanced testicular degeneration (0.7 +/- 0.8 nM), dogs with hypoplastic testicles (0.8 +/- 0.9 nM) and dogs with one degenerated and one retained testis or with bilateral cryptorchidism (1.2 +/- 0.9 nM) compared to dogs with one or two normal testes (7.0 +/- 5.5 nM). Testicular volume and weight were significantly lower in degenerated, hypoplastic and retained testes compared with the contralateral normal testis. Some spermatogenic activity was found in three of the retained testes, producing oligozoospermic smears with a high percentage of sperm abnormalities. No comparable epidemiological data about male pathological conditions of the reproductive organs in the dog is available. The prevalence found in this study, yet, appears high.

  6. An Evaluation of Deviation from the International Atomic Energy Agency-International Commission on Radiological Protection Proposed Equation for Calculation of Radiation Dose Rate Emanating from the Patients with Differentiated Thyroid Cancer Undergoing Radioiodine (I-131) Therapy.

    Science.gov (United States)

    Dehkordi, Forough Jafarian; Rasuli, Behrouz; Mahmoud-Pashazadeh, Ali

    2017-01-01

    The main purpose of this study was to investigate dose rate emanating from patients treated with (131)I to evaluate which of the theoretical formulas, inverse-square law (ISL) and International Atomic Energy Agency-International Commission on Radiological Protection (IAEA-ICRP) suggested equation, can provide a sufficiently close approximation of the measured dose rate. Measurements were performed based on the IAEA safety report No. 63 method at 0, 12, 24, and 48 h after administration of radioiodine at a distance of 1 m for 69 patients and for the rest of 67 patients, dose rate was measured at 2, 4, 24, and 48 h at a distance of 2 m. Results revealed that the ISL formula gained better approximation of measured dose rates than the IAEA-ICRP equation with the lesser error. The ISL formula is still more reliable than the novel method of dose calculation in the vicinity of patients. This finding reminded us the prime importance of distance as a radiation protection principle.

  7. Ground vibrations emanating from construction equipment.

    Science.gov (United States)

    2012-09-01

    The recent trend in highway construction within New Hampshire has been toward reconstruction and rehabilitation projects in congested urban areas. This has resulted in a greater concern for vibrations generated by non-blasting construction activities...

  8. Temporal relationships between the variations of diffuse gaseous emanations and the explosive activity of some active volcanoes of Costa-Rica, examples at the Arenal, Irazu and at the Rincon de la Vieja; Relations temporelles entre les variations des emanations gazeuses diffuses et l`activite explosive de quelques volcans actifs du Costa-Rica, exemples a l`Arenal, l`Irazu et au Rincon de la Vieja

    Energy Technology Data Exchange (ETDEWEB)

    Baubron, J.C. [BRGM, 45 - Orleans (France); Allard, P. [CEA Centre d`Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Direction des Sciences de la Matiere; Fernandez, E. [Obviscori, Heridia (Costa Rica); Hammouya, G. [Observatoire de la Soufriere, IPG-P, le Houelmont, 97 - Gourgeyre (France); Soto, G.J. [ICE, San Jose (Costa Rica)

    1996-12-31

    The surveillance of the temporal evolution of radon and helium concentrations in the carbon dioxide of crater fumaroles and gaseous emanations is performed since 1992 on the Irazu, Arenal, Poas and Rincon de la Vieja volcanoes in Costa-Rica. The {sup 3}He/{sup 4}He ratio is used as an indicator of the deep origin of the volcanic gas while radon is an indicator of the CO{sub 2} flux. Radon measurements performed on the Irazu show a continuous decay of radon concentration in the intra-crater fumaroles with an important increase of the gaseous flux since 1992. On the contrary, the external fumaroles on the NW flank were characterized by an important increase in radon concentration in 1994 with a stable flux. The radon surveillance performed in soils around the volcano has shown an intense increase of the diffuse gaseous flows probably linked to the micro-seismic activity of the volcano. Similar observations are reported for the Rincon de la Vieja volcano and correlated with its eruptive history and its phreatic and phreato-magmatic activity. Short paper. (J.S.).

  9. LUPIN, a new instrument for pulsed neutron fields

    Science.gov (United States)

    Caresana, M.; Ferrarini, M.; Manessi, G. P.; Silari, M.; Varoli, V.

    2013-06-01

    A number of studies focused in the last decades on the development of survey meters to be used in pulsed radiation fields. This is a topic attracting widespread interest for applications such as radiation protection and beam diagnostics in accelerators. This paper describes a new instrument specifically conceived for applications in pulsed neutron fields (PNF). The detector, called LUPIN, is a rem counter type instrument consisting of a 3He proportional counter placed inside a spherical moderator. It works in current mode with a front-end electronics consisting of a current-voltage logarithmic amplifier, whose output signal is acquired with an ADC and processed on a PC. This alternative signal processing allows the instrument to be used in PNF without being affected by saturation effects. Moreover, it has a measurement capability ranging over many orders of burst intensity. Despite the fact that it works in current mode, it can measure a single neutron interaction. The LUPIN was first calibrated in CERN's calibration laboratory with a PuBe source. Measurements were carried out under various experimental conditions at the Helmholtz-Zentrum in Berlin, in the stray field at various locations of the CERN Proton Synchrotron complex and around a radiotherapy linear accelerator at the S. Raffaele hospital in Milan. The detector can withstand single bursts with values of H*(10) up to 16 nSv/burst without showing any saturation effect. It efficiently works in pulsed stray fields, where a conventional rem-counter underestimates by a factor of 2. It is also able to reject the very intense and pulsed photon contribution that often accompanies the neutron field with good reliability.

  10. Bacterial and protozoal agents of canine vector-borne diseases in the blood of domestic and stray dogs from southern Portugal.

    Science.gov (United States)

    Maia, Carla; Almeida, Bruno; Coimbra, Mónica; Fernandes, Maria Catarina; Cristóvão, José Manuel; Ramos, Cláudia; Martins, Ângela; Martinho, Filipe; Silva, Pedro; Neves, Nuno; Nunes, Mónica; Vieira, Maria Luísa; Cardoso, Luís; Campino, Lenea

    2015-03-23

    The so-called canine vector-borne diseases (CVBD) are caused by a wide range of pathogens transmitted by arthropods. In addition to their veterinary importance, many of these canine vector-borne pathogens can also affect the human population due to their zoonotic potential, a situation that requires a One Health approach. As the prevalence of vector-borne pathogens in cats from southern Portugal has been recently evaluated, the aim of the present study was to assess if the same agents were present in dogs living in the same area, and to assess positivity-associated risk factors. One thousand and ten dogs (521 domestic and 489 stray) from veterinary medical centres and animal shelters in southern Portugal were enrolled. Anaplasma spp./Ehrlichia spp., Bartonella spp., Borrelia burgdorferi sensu lato, Babesia spp., Hepatozoon spp. and Leishmania infantum infections were evaluated by polymerase chain reaction (PCR) assays in blood samples. Sixty-eight (6.7%) dogs were PCR-positive to at least one of the tested CVBD agent species, genera or complex, including one dog found positive to two different genera. Nineteen (1.9%) dogs were positive to Anaplasma spp./Ehrlichia spp., eight (0.8%) to B. burgdorferi s.l., 31 (3.1%) to Hepatozoon spp. and 11 (1.1%) to L. infantum. Anaplasma platys, Ehrlichia canis, B. burgdorferis.l. and Hepatozoon canis were identified by DNA sequencing, including one animal confirmed with both A. platys and H. canis. Furthermore, Wolbachia spp. was amplified in blood from four dogs. None of the tested dogs was positive by PCR for Bartonella spp. or Babesia spp. The molecular identification of CVBD agents in southern Portugal, some of them with zoonotic concern, reinforces the importance to alert the veterinary community, owners and public health authorities to prevent the risk of transmission of vector-borne pathogens among dogs and to other vertebrate hosts including humans. The prevalence of the selected pathogens was lower than that previously

  11. Self-magnetic-leakage field detection using magneto-optical sensor technique

    Directory of Open Access Journals (Sweden)

    Stegemann Robert

    2014-06-01

    Full Text Available Measurement of spontaneous magnetic stray field signals has been reported to be a promising tool for capturing macro-scale information of deformation states, defects and stress concentration zones in a material structure. This paper offers a new method for self-magnetic leakage field detection using a magneto-optical (MO hand-held microscope. Its sensor has a dynamic field range between ±0.05 and ±2 kA/m and a lateral optical resolution of approx. 10 μm. We examined flat tensile test specimens of metastable austenitic steel AISI 304. Static tensile tests were repeatedly interrupted at various predetermined states of strain and the magnetic information was measured by the MO system. Comparative measurements using a high-precision magnetic field GMR-sensor, verify the outstanding capability of the MO microscope regarding spatial resolution of magnetic fields.

  12. Dose equivalent measurements in a strongly pulsed high-energy radiation field

    CERN Document Server

    Mayer, S; Kyllonen, J E; Menzel, Hans Gregor; Otto, Thomas

    2004-01-01

    The stray radiation field outside the shielding of high-energy accelerators comprises neutrons, photons and charged particles with a wide range of energies. Often, accelerators operate by accelerating and ejecting short pulses of particles, creating an analogue, pulsed radiation field. The pulses can be as short as 10 mu s with high instantaneous fluence rates and dose rates. Measurements of average dose equivalent (rate) for radiation protection purposes in these fields present a challenge for instrumentation. The performance of three instruments (i.e. a recombination chamber, the Sievert Instrument and a HANDITEPC) measuring total dose equivalent is compared in a high-energy reference radiation field (CERF) and a strongly pulsed, high-energy radiation field at the CERN proton synchrotron (PS).

  13. 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.

  14. An expansion of the field modulus suitable for the description of strong field gradients in axisymmetric magnetic fields: application to single-sided magnet design, field mapping and STRAFI.

    Science.gov (United States)

    Hugon, Cedric; Aubert, Guy; Sakellariou, Dimitris

    2012-01-01

    Mapping (or plotting) the magnetic field has a critical importance for the achievement of the homogeneous magnetic field necessary to standard MR experiments. A powerful tool for this purpose is the Spherical Harmonic Expansion (SHE), which provides a simple way to describe the spatial variations of a field in free space. Well-controlled non-zero spatial variations of the field are critical to MRI. The resolution of the image is directly related to the strength of the gradient used to encode space. As a result, it is desirable to have strong variations of the field. In that case, the SHE cannot be used as is, because the field modulus variations are affected by the variations of all components of the field. In this paper, we propose a method based on the SHE to characterize such variations, theoretically and experimentally, in the limit of an axisymmetric magnetic field. Practical applications of this method are proposed through the examples of single-sided magnet design and characterization, along with Stray-Field Imaging (STRAFI). Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Measurements of size distributions of radon progeny for improved quantification of the lung cancer risk emanating from exposure to radon decay products; Messungen der Groessenverteilungen von Radon-Folgeprodukten zur Verbesserung der Quantifizierung des durch Radonexposition verursachten Lungenkrebsrisikos

    Energy Technology Data Exchange (ETDEWEB)

    Haninger, T.

    1997-12-31

    A major issue in radiation protection is to protect the population from the harmful effects of exposure to radon and radon progeny. Quantification of the lung cancer risk emanating from exposure to radon decay products in residential and working environments poses problems, as epidemiologic studies yield information deviating from the results obtained by the indirect method of assessment based on dosimetric respiratory tract models. One important task of the publication here was to characterize the various exposure conditions and to quantify uncertainties that may result from application of the ``dose conversion convention``. A special aerosol spectrometer was therefore designed and built in order to measure the size distributions of the short-lived radon decay products in the range between 0.5 nm and 10 000 nm. The aerosol spectrometer consists of a three-step diffusion battery with wire nets, an 11-step BERNER impactor, and a detector system with twelve large-surface proportional detectors. From the measured size distributions, dose conversion coefficients, E/P{sup eq}, were calculated using the PC software RADEP; the RADEP program was developed by BIRCHALL and JAMES and is based on the respiratory tract model of the ICRP. The E/P{sup eq} coefficients indicate the effective dose E per unit exposure P{sup eq} to radon decay products. (orig./CB) [Deutsch] Eines der groessten Probleme des Strahlenschutzes ist der Schutz der Bevoelkerung vor einer Strahlenexposition durch Radon und seine Folgeprodukte. Die Quantifizierung des Lungenkrebsrisikos, das durch Radonexpositionen in Wohnungen und an Arbeitsplaetzen verursacht wird, ist ein grosses Problem, weil epidemiologische Studien ein anderes Ergebnis liefern, als die indirekte Methode der Abschaetzung mit dosimetrischen Atemtrakt-Modellen. Eine wichtige Aufgabe der vorliegenden Arbeit war es, unterschiedliche Expositionsbedingungen zu charakterisieren und die Unsicherheiten zu quantifizieren, die sich aus der

  16. Relationship between water chemistry and sediment mineralogy in the Cerro Prieto geothermal field: a preliminary report

    Energy Technology Data Exchange (ETDEWEB)

    Valette-Silver, J.N. (Univ. de Perpignan, France); Thompson, J.M.; Ball, J.W.

    1981-01-01

    The chemical compositions of waters collected from the Cerro Prieto geothermal production wells and hydrothermal emanations are different. Compared to the Cerro Prieto well waters, the surficial waters generally contain significantly less potassium, slightly less calcium and chloride, and significantly more magnesium and sulfate. In comparison to the unaltered sediments, the changes in the mineralogy of the altered sediments appear to be controlled by the type of emanation (well, spring, mud pot, geyser, fumarole, or cold pool). However, an increase in quartz and potassium feldspar percentages seems to be characteristic of the majority of the sediments in contact with geothermal fluids. Preliminary attempts to model the chemical processes occurring in the Cerro Prieto geothermal field using chemical equilibrium calculations are reported. For this purpose the chemical compositions of thermal waters (well and surficial emanation) were used as input data to make calculations with SOLMNEQ and WATEQ2 computer programs. Then the theoretical mineral composition of altered sediments was predicted and compared to the mineralogy actually observed in the solid samples.

  17. A facility for X-ray diffraction in magnetic fields up to 25 T and temperatures between 15 and 295 K

    Energy Technology Data Exchange (ETDEWEB)

    Wang, S.; Kovalev, A. E., E-mail: kovalev@magnet.fsu.edu; Suslov, A. V. [National High Magnetic Field Laboratory, Tallahassee, Florida 32310 (United States); Siegrist, T. [National High Magnetic Field Laboratory, Tallahassee, Florida 32310 (United States); Department of Chemical & Biomedical Engineering, FAMU-FSU College of Engineering, Tallahassee, Florida 32310 (United States)

    2015-12-15

    A facility for X-ray diffraction has been developed at the National High Magnetic Field Laboratory. It brings diffraction capability to the 25 T Florida split coil magnet and implements temperature control in a range of 15–295 K using a cold finger helium cryostat. This instrument represents an alternative to pulsed magnetic field systems, and it exceeds the static magnetic fields currently available at synchrotron facilities. Magnetic field compatibility of an X-ray source and detectors with the sizable magnetic fringe fields emanating from the magnet constrained the design of the diffractometer.

  18. Variations of atmospheric electric field and meteorological parameters in Kamchatka in 1997-2016

    Directory of Open Access Journals (Sweden)

    Smirnov Sergey

    2017-01-01

    Full Text Available Analysis of seasonal and annual variations of aero-electric field at a midlatitudinal observatory Paratunka in Kamchatka was carried out for 1997-2016. Stable seasonal intervals of the highest and the lowest values are observed. Changeability of the annual trend of aero-electric field in the near ground air layer at the observatory located in an active geodynamic region is shown. A large positive trend was changed by a smooth negative one. It is likely to be associated either with radon emanation intensity change in the observatory region or with volcanic activity change in Kamchatka.

  19. Noncyclic geometric phases and helicity transitions for neutrino oscillations in a magnetic field

    Science.gov (United States)

    Joshi, Sandeep; Jain, Sudhir R.

    2017-11-01

    We show that neutrino spin and spin-flavor transitions involve nonvanishing geometric phases. The geometric character of neutrino spin rotation is explored by studying the neutrino spin trajectory in the projective Hilbert space representation and its relation to the geometric phase. Analytical expressions are derived for noncyclic geometric phases. Several calculations are performed for different cases of rotating and nonrotating magnetic fields in the context of solar neutrinos and neutrinos produced inside neutron stars. Also the effects of adiabaticity, critical magnetic fields, and cross boundary effects in the case of neutrinos emanating out of neutron stars are examined.

  20. Dose equivalent measurements in mixed and time varying radiation fields around high-energy accelerators

    CERN Document Server

    Mayer, S

    2003-01-01

    Measurements of ambient dose equivalent in stray radiation fields behind the shielding of high-energy accelerators are a challenging task. Several radiation components (photons, neutrons, charged particles, muons, etc.), spanning a wide range of energies, contribute to the total dose equivalent. The radiation fields are produced by beam losses interacting with structural material during the acceleration or at the ejection to experimental areas or other accelerators. The particle beam is usually not continuous but separated in "bunches" or pulses, which further complicates dose measurements at high-energy accelerators. An ideal dosimeter for operational radiation protection should measure dose equivalent for any composition of radiation components in the entire energy range even when the field is strongly pulsed. The objective of this work was to find out if an ionisation chamber operated as a "recombination chamber" and a TEPC instrument using the variance-covariance method ("Sievert Instrument") are capable ...

  1. Nongyrotropic Electrons in Guide Field Reconnection

    Science.gov (United States)

    Wendel, D. E.; Hesse, M.; Bessho, N.; Adrian, M. L.; Kuznetsova, M.

    2016-01-01

    We apply a scalar measure of nongyrotropy to the electron pressure tensor in a 2D particle-in-cell simulation of guide field reconnection and assess the corresponding electron distributions and the forces that account for the nongyrotropy. The scalar measure reveals that the nongyrotropy lies in bands that straddle the electron diffusion region and the separatrices, in the same regions where there are parallel electric fields. Analysis of electron distributions and fields shows that the nongyrotropy along the inflow and outflow separatrices emerges as a result of multiple populations of electrons influenced differently by large and small-scale parallel electric fields and by gradients in the electric field. The relevant parallel electric fields include large-scale potential ramps emanating from the x-line and sub-ion inertial scale bipolar electron holes. Gradients in the perpendicular electric field modify electrons differently depending on their phase, thus producing nongyrotropy. Magnetic flux violation occurs along portions of the separatrices that coincide with the parallel electric fields. An inductive electric field in the electron EB drift frame thus develops, which has the effect of enhancing nongyrotropies already produced by other mechanisms and under certain conditions producing their own nongyrotropy. Particle tracing of electrons from nongyrotropic populations along the inflows and outflows shows that the striated structure of nongyrotropy corresponds to electrons arriving from different source regions. We also show that the relevant parallel electric fields receive important contributions not only from the nongyrotropic portion of the electron pressure tensor but from electron spatial and temporal inertial terms as well.

  2. Visual field

    Science.gov (United States)

    Perimetry; Tangent screen exam; Automated perimetry exam; Goldmann visual field exam; Humphrey visual field exam ... Confrontation visual field exam. This is a quick and basic check of the visual field. The health care provider ...

  3. Tumor treating fields therapy device for glioblastoma: physics and clinical practice considerations.

    Science.gov (United States)

    Lok, Edwin; Swanson, Kenneth D; Wong, Eric T

    2015-01-01

    Alternating electric fields therapy, as delivered by the tumor treating fields device, is a new modality of cancer treatment that has been approved by the US FDA for recurrent glioblastoma. At a frequency of 200 kHz, these fields emanate from transducer arrays on the surface of the patient's scalp into the brain and perturb processes necessary for cytokinesis during tumor cell mitosis. In the registration Phase III trial for recurrent glioblastoma patients, the efficacy of the tumor treating fields as monotherapy was equivalent to chemotherapy, while scalp irritation was its major adverse event compared with systemic toxicities that were associated with cytotoxic chemotherapies. Alternating electric fields therapy is, therefore, an essential option for the treatment of recurrent glioblastoma. Here, we summarize our current knowledge of the physics, cell biology and clinical data supporting the use of the tumor treating fields therapy.

  4. The Temperature - Magnetic Field Relation in Observed and Simulated Sunspots

    Science.gov (United States)

    Sobotka, Michal; Rezaei, Reza

    2017-12-01

    Observations of the relation between continuum intensity and magnetic field strength in sunspots have been made for nearly five decades. This work presents full-Stokes measurements of the full-split (g = 3) line Fe i 1564.85 nm with a spatial resolution of 0.5^'' obtained with the GREGOR Infrared Spectrograph in three large sunspots. The continuum intensity is corrected for instrumental scattered light, and the brightness temperature is calculated. Magnetic field strength and inclination are derived directly from the line split and the ratio of Stokes components. The continuum intensity (temperature) relations to the field strength are studied separately in the umbra, light bridges, and penumbra. The results are consistent with previous studies, and it was found that the scatter of values in the relations increases with increasing spatial resolution thanks to resolved fine structures. The observed relations show trends common for the umbra, light bridges, and the inner penumbra, while the outer penumbra has a weaker magnetic field than the inner penumbra at equal continuum intensities. This fact can be interpreted in terms of the interlocking comb magnetic structure of the penumbra. A comparison with data obtained from numerical simulations was made. The simulated data generally have a stronger magnetic field and a weaker continuum intensity than the observations, which may be explained by stray light and limited spatial resolution of the observations, and also by photometric inaccuracies of the simulations.

  5. LUPIN, a new instrument for pulsed neutron fields

    Energy Technology Data Exchange (ETDEWEB)

    Caresana, M. [Politecnico di Milano, Department of Energy, Via Ponzio 34/3, 20133 Milan (Italy); Ferrarini, M. [Politecnico di Milano, Department of Energy, Via Ponzio 34/3, 20133 Milan (Italy); CNAO, Via Privata Campeggi, 27100 Pavia (Italy); Manessi, G.P., E-mail: giacomo.paolo.manessi@cern.ch [CERN, 1211 Geneva 23 (Switzerland); University of Liverpool, Department of Physics, L69 7ZE Liverpool (United Kingdom); Silari, M. [CERN, 1211 Geneva 23 (Switzerland); Varoli, V. [Politecnico di Milano, Department of Energy, Via Ponzio 34/3, 20133 Milan (Italy)

    2013-06-01

    A number of studies focused in the last decades on the development of survey meters to be used in pulsed radiation fields. This is a topic attracting widespread interest for applications such as radiation protection and beam diagnostics in accelerators. This paper describes a new instrument specifically conceived for applications in pulsed neutron fields (PNF). The detector, called LUPIN, is a rem counter type instrument consisting of a {sup 3}He proportional counter placed inside a spherical moderator. It works in current mode with a front-end electronics consisting of a current–voltage logarithmic amplifier, whose output signal is acquired with an ADC and processed on a PC. This alternative signal processing allows the instrument to be used in PNF without being affected by saturation effects. Moreover, it has a measurement capability ranging over many orders of burst intensity. Despite the fact that it works in current mode, it can measure a single neutron interaction. The LUPIN was first calibrated in CERN's calibration laboratory with a PuBe source. Measurements were carried out under various experimental conditions at the Helmholtz-Zentrum in Berlin, in the stray field at various locations of the CERN Proton Synchrotron complex and around a radiotherapy linear accelerator at the S. Raffaele hospital in Milan. The detector can withstand single bursts with values of H⁎(10) up to 16 nSv/burst without showing any saturation effect. It efficiently works in pulsed stray fields, where a conventional rem-counter underestimates by a factor of 2. It is also able to reject the very intense and pulsed photon contribution that often accompanies the neutron field with good reliability. -- Highlights: ► LUPIN is a new detector specifically conceived to work in neutron pulsed fields. ► The detector is a rem counter type instrument working in current mode. ► The performances of the detectors were studied under various experimental conditions. ► The detector

  6. Study on the change of aspect ratios of small surface cracks emanated from a toe of corner boxing; Mawashi yosetsudome tanbu kara hassei denpasuru bishi bisho hyomen kiretsu no aspect hi henka ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Toyosada, M.; Yamaguchi, K.; Takeda, K.; Watanabe, Y. [Kyushu University, Fukuoka (Japan). Faculty of Engineering

    1997-10-01

    The fatigue test of specimens with a stiffener was carried out to examine the change in aspect ratio (crack depth/length) of fatigue cracks in a stress concentration field and residual stress field. The aspect ratio of surface cracks just after generation can be represented with the single virtual surface crack with the same value as K value at the deepest point considering an interference effect from near cracks. No discontinuous change in K value is found at the deepest point even during growth and combination of cracks on a surface. The change in K value at the deepest point is thus the criterion to represent growth and combination of surface cracks considering the interference effect. The change in aspect ratio of the typical single virtual surface crack linearly decreases with an increase in crack depth. The shape of surface cracks generating and growing in a residual stress field is more flat than that in no residual stress field. In addition, in a residual stress field, surface cracks are longer at the same crack depth, and fatigue lives are shorter. 7 refs., 12 figs.

  7. High-field penning-malmberg trap: confinement properties and use in positron accumulation

    Energy Technology Data Exchange (ETDEWEB)

    Hartley, J.H.

    1997-09-01

    This dissertation reports on the development of the 60 kG cryogenic positron trap at Lawrence Livermore National Laboratory, and compares the trap`s confinement properties with other nonneutral plasma devices. The device is designed for the accumulation of up to 2{times}10{sup 9} positrons from a linear-accelerator source. This positron plasma could then be used in Bhabha scattering experiments. Initial efforts at time-of-flight accumulation of positrons from the accelerator show rapid ({approximately}100 ms) deconfinement, inconsistent with the long electron lifetimes. Several possible deconfinement mechanisms have been explored, including annihilation on residual gas, injection heating, rf noise from the accelerator, magnet field curvature, and stray fields. Detailed studies of electron confinement demonstrate that the empirical scaling law used to design the trap cannot be extrapolated into the parameter regime of this device. Several possible methods for overcoming these limitations are presented.

  8. Field Guide to Challenges and Opportunities in Antibody-Drug Conjugates for Chemists

    Science.gov (United States)

    Gordon, Mallory R.; Canakci, Mine; Li, Longyu; Zhuang, Jiaming; Osborne, Barbara; Thayumanavan, S.

    2016-01-01

    Antibody-drug conjugates have attracted a great amount of attention as a therapeutic strategy for diseases where targeting specific tissues and cells are critical components, such as in cancer therapy. Although promising, the number of approved ADC drugs is relatively limited. This emanates from the challenges associated with generating the conjugates and the complexities associated with the stability requirements for these conjugates during circulation and after reaching the target. Here, we provide a comprehensive overview of the design challenges facing the ADC field. These challenges also provide several unique research and development opportunities, which are also highlighted throughout the review. PMID:26308881

  9. Creation and recovery of a W(111) single atom gas field ion source.

    Science.gov (United States)

    Pitters, Jason L; Urban, Radovan; Wolkow, Robert A

    2012-04-21

    Tungsten single atom tips have been prepared from a single crystal W(111) oriented wire using the chemical assisted field evaporation and etching method. Etching to a single atom tip occurs through a symmetric structure and leads to a predictable last atom unlike etching with polycrystalline tips. The single atom tip formation procedure is shown in an atom by atom removal process. Rebuilds of single atom tips occur on the same crystalline axis as the original tip such that ion emission emanates along a fixed direction for all tip rebuilds. This preparation method could be utilized and developed to prepare single atom tips for ion source development.

  10. Dosimetry in radiation fields around high-energy proton accelerators

    CERN Document Server

    Agosteo, S; Silari, M; Theis, C

    2008-01-01

    Radiation dosimetry at high-energy proton accelerators is a difficult task because of the complexity of the stray radiation field. A good knowledge of this mixed radiation field is very important to be able to select the type of detectors (active and/or passive) to be employed for routine area monitoring and to choose the personal dosimeter legally required for estimating the effective dose received by individuals. At the same time, the response function of the detectors to the mixed field must be thoroughly understood. A proper calibration of a device, which may involve a complex series of measurements in various reference fields, is needed. Monte Carlo simulations provide a complementary – and sometimes the principal – mean of determining the response function. The ambient dose equivalent rates during operation range from a few hundreds of μSv per year to a few mSv per year. To measure such rates one needs detectors of high sensitivity and/or capable of integrating over long periods. The main challenge...

  11. Phase Field

    Science.gov (United States)

    Koyama, Toshiyuki

    The term phase field has recently become known across many fields of materials science. The meaning of phase field is the spatial and temporal order parameter field defined in a continuum-diffused interface model. By using the phase field order parameters, many types of complex microstructure changes observed in materials science are described effectively. This methodology has been referred to as the phase field method, phase field simulation, phase field modeling, phase field approach, etc. In this chapter, the basic concept and theoretical background for the phase field approach is explained in Sects. 21.1 and 21.2. The overview of recent applications of the phase field method is demonstrated in Sects. 21.3 to 21.6.

  12. Estructura comunitaria de helmintos de perros vagabundos de San Juan de Lurigancho, Lima, Perú Community structure of helminths in stray dogs from San Juan de Lurigancho, Lima, Peru

    Directory of Open Access Journals (Sweden)

    José O. Iannacone

    2001-07-01

    Full Text Available Thirty stray dogs Canis familiaris Linnaeus, 1758 were collected in San Juan de Lurigancho, Lima, Peru, between January and March 1997 and necropsied for helminths. Three species were collected: the cestodes Dipylidium caninum (Linnaeus, 1758 Railliet, 1892 and Taenia pisiformis (Bloch, 1780 and the nematode Toxocara canis (Werner, 1782 Stiles, 1905. Fifty per cent of the examined dogs showed one or two parasites. A total of 303 (0-116 helminths were recovered and the intensity of infection was 30,3. The Simpson index (C for all parasite species was 0,414, indicating a dominance by one species in the parasite community. The mean diversity in the infracommunities of C. familiaris was H' = 0,038 and uniformity index of Pielou J = 0,207. Dipylidium caninum, T. pisiformis, and T. canis presented a prevalence of infection of 33,30%, 10% and 16,6% respectively. Dipylidium caninum presented the highest frequency and mean intensity of infection. Dipylidium caninum was the helminth with the highest dominance (94% whereas the lowest was due to T. pisiformis (4% and T. canis (2%. Helminths were not related to the age of the hosts, prevalence and mean intensity of infection. Out of the 10 equally divided segments of the intestinal gut, D. caninum was found from the 6th to the 9th segment. T canis preferred almost exclusively the 1st segment while T. pisiformis was randomly distributed.

  13. Reception and learning of electric fields in bees.

    Science.gov (United States)

    Greggers, Uwe; Koch, Gesche; Schmidt, Viola; Dürr, Aron; Floriou-Servou, Amalia; Piepenbrock, David; Göpfert, Martin C; Menzel, Randolf

    2013-05-22

    Honeybees, like other insects, accumulate electric charge in flight, and when their body parts are moved or rubbed together. We report that bees emit constant and modulated electric fields when flying, landing, walking and during the waggle dance. The electric fields emitted by dancing bees consist of low- and high-frequency components. Both components induce passive antennal movements in stationary bees according to Coulomb's law. Bees learn both the constant and the modulated electric field components in the context of appetitive proboscis extension response conditioning. Using this paradigm, we identify mechanoreceptors in both joints of the antennae as sensors. Other mechanoreceptors on the bee body are potentially involved but are less sensitive. Using laser vibrometry, we show that the electrically charged flagellum is moved by constant and modulated electric fields and more strongly so if sound and electric fields interact. Recordings from axons of the Johnston organ document its sensitivity to electric field stimuli. Our analyses identify electric fields emanating from the surface charge of bees as stimuli for mechanoreceptors, and as biologically relevant stimuli, which may play a role in social communication.

  14. Instrument intercomparison in the high-energy mixed field at the CERN-EU reference field (CERF) facility.

    Science.gov (United States)

    Caresana, Marco; Helmecke, Manuela; Kubancak, Jan; Manessi, Giacomo Paolo; Ott, Klaus; Scherpelz, Robert; Silari, Marco

    2014-10-01

    This paper discusses an intercomparison campaign performed in the mixed radiation field at the CERN-EU (CERF) reference field facility. Various instruments were employed: conventional and extended-range rem counters including a novel instrument called LUPIN, a bubble detector using an active counting system (ABC 1260) and two tissue-equivalent proportional counters (TEPCs). The results show that the extended range instruments agree well within their uncertainties and within 1σ with the H*(10) FLUKA value. The conventional rem counters are in good agreement within their uncertainties and underestimate H*(10) as measured by the extended range instruments and as predicted by FLUKA. The TEPCs slightly overestimate the FLUKA value but they are anyhow consistent with it when taking the comparatively large total uncertainties into account, and indicate that the non-neutron part of the stray field accounts for ∼30 % of the total H*(10). © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. High prevalence and variability of CTX-M-15-producing and fluoroquinolone-resistant Escherichia coli observed in stray dogs in rural Angola.

    Science.gov (United States)

    Albrechtova, Katerina; Kubelova, Michaela; Mazancova, Jana; Dolejska, Monika; Literak, Ivan; Cizek, Alois

    2014-08-01

    Antimicrobial resistance (AMR) represents a serious problem globally, but it is especially pronounced in the tropics, where pressure of infectious diseases is high. We examined resistance in Escherichia coli colonizing gastrointestinal tracts of 17 dogs which have never received antimicrobial treatment, living in central rural Angola. Emphasis was placed on extended-spectrum beta-lactamases (ESBL) and plasmid-mediated quinolone resistance (PMQR). Resistance-carrying plasmids were characterized in size, group of incompatibility and ability to conjugate. Isolates were compared by their pulsed-field gel electrophoresis (PFGE) profiles. Detailed description of 19 E. coli isolates with either ESBL or PMQR genes carried on multiresistant plasmids of different groups of incompatibility indicates that dogs, despite never being treated by antibiotics, are important reservoirs and transmitters of AMR in the study area.

  16. Optical design of FRIDA, the integral-field spectrograph and imager for the AO system of the Gran Telescopio Canarias

    Science.gov (United States)

    Cuevas, Salvador; Eikenberry, Stephen S.; Sánchez, Beatriz; Chapa, Oscar; Espejo, Carlos; Flores-Meza, Rubén; Lara, Gerardo; Álvarez, Luis C.; Keiman, Carolina

    2008-07-01

    FRIDA (inFRared Imager and Dissector for the Adaptive optics system of the Gran Telescopio Canarias) has been designed as a diffraction limited instrument that will offer broad and narrow band imaging and integral field spectroscopy (IFS) capabilities with low, intermediate and high spectral resolutions to operate in the wavelength range 0.9 - 2.5 μm. The integral field unit is based on a monolithic image slicer based on the University of Florida FISICA. Both, the imaging mode and IFS observing modes will use the same Rockwell 2K×2K detector. FRIDA will be based at a Nasmyth focus of GTC, behind the GTCAO system. The FRIDA optical design, stray light analysis, tolerance analysis and manufacturing feasibility are described in this contribution.

  17. Broadband measurements of high-frequency electric field levels and exposure ratios determination

    Directory of Open Access Journals (Sweden)

    Vulević Branislav

    2017-01-01

    Full Text Available The exposure of people to high-frequency electromagnetic fields (over 100 kHz that emanate from modern wireless information transmission systems is inevitable in modern times. Due to the rapid development of new technologies, measuring devices and their connection to measuring systems, the first fifteen years of the 21st century are characterized by the appearance of different approaches to measurements. This prompts the need for the assessment of the exposure of people to these fields. The main purpose of this paper is to show how to determine the exposure ratios based on the results of broadband measurements of the high-frequency electric field in the range of 3 MHz to 18 GHz in the environment.

  18. Magnetic Field

    DEFF Research Database (Denmark)

    Olsen, Nils

    2015-01-01

    of the fluid flow at the top of the core. However, what is measured at or near the surface of the Earth is the superposition of the core field and fields caused by magnetized rocks in the Earth’s crust, by electric currents flowing in the ionosphere, magnetosphere, and oceans, and by currents induced......he Earth has a large and complicated magnetic field, the major part of which is produced by a self-sustaining dynamo operating in the fluid outer core. Magnetic field observations provide one of the few tools for remote sensing the Earth’s deep interior, especially regarding the dynamics...... in the Earth by time-varying external fields. These sources have their specific characteristics in terms of spatial and temporal variations, and their proper separation, based on magnetic measurements, is a major challenge. Such a separation is a prerequisite for remote sensing by means of magnetic field...

  19. Health risks of electromagnetic fields. Part I: Evaluation and assessment of electric and magnetic fields.

    Science.gov (United States)

    Habash, Riadh W Y; Brodsky, Lynn M; Leiss, William; Krewski, Daniel; Repacholi, Michael

    2003-01-01

    Exposure to electric and magnetic fields (EMF) emanating from the generation, distribution, and utilization of electricity is widespread. The major debate in recent years has focused on the possibility that exposure to EMF may result in adverse health consequences, including the development of cancer. This article provides a review and evaluation of potential health risks associated with residential and occupational exposure to EMF. In addition to reviewing data from laboratory, epidemiology, and clinical studies, we examine exposure data from field measurement surveys and exposure guidelines that have been established for EMF. Currently, the evidence in support of an association between EMF and childhood cancer is limited, although this issue warrants further investigation. Evidence of an association between EMF exposure and adult cancers, derived largely from occupational settings, is inconsistent, precluding clear conclusions. There is little evidence of an association between EMF and noncancer health effects. Epidemiological studies of EMF and population health are limited by exposure measurement error and the lack of a clear dose/response relationship in studies suggesting possible health risks. Further research is needed to clarify the ambiguous findings from present studies and to determine if EMF exposure poses a health risk.

  20. Electric field driven torque in ATP synthase.

    Directory of Open Access Journals (Sweden)

    John H Miller

    Full Text Available FO-ATP synthase (FO is a rotary motor that converts potential energy from ions, usually protons, moving from high- to low-potential sides of a membrane into torque and rotary motion. Here we propose a mechanism whereby electric fields emanating from the proton entry and exit channels act on asymmetric charge distributions in the c-ring, due to protonated and deprotonated sites, and drive it to rotate. The model predicts a scaling between time-averaged torque and proton motive force, which can be hindered by mutations that adversely affect the channels. The torque created by the c-ring of FO drives the γ-subunit to rotate within the ATP-producing complex (F1 overcoming, with the aid of thermal fluctuations, an opposing torque that rises and falls with angular position. Using the analogy with thermal Brownian motion of a particle in a tilted washboard potential, we compute ATP production rates vs. proton motive force. The latter shows a minimum, needed to drive ATP production, which scales inversely with the number of proton binding sites on the c-ring.

  1. Gauge fields

    CERN Document Server

    Itzykson, C

    1978-01-01

    Some background on the theory of gauge fields, a subject of increasing popularity among particle physicists, is provided. The aim will be to stress those aspects which suggest that gauge fields may play some role in a future theory of strong interactions. (8 refs).

  2. Field Report

    DEFF Research Database (Denmark)

    Gorm Hansen, Louise Lyngfeldt

    2012-01-01

    This field report expresses perfectly the kind of confusion almost all of us experience when entering the field. How do we know whether what we’re doing is “right” or not? What in particular should we record when we don’t have time to write down everything among all the myriad impressions thrusting...

  3. Electron cyclotron resonance heating by magnetic filter field in a negative hydrogen ion source

    Energy Technology Data Exchange (ETDEWEB)

    Kim, June Young, E-mail: beacoolguy@snu.ac.kr; Cho, Won-Hwi; Dang, Jeong-Jeung; Chung, Kyoung-Jae, E-mail: jkjlsh1@snu.ac.kr; Hwang, Y. S. [Department of Nuclear Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of)

    2016-02-15

    The influence of magnetic filter field on plasma properties in the heating region has been investigated in a planar-type inductively coupled radio-frequency (RF) H{sup −} ion source. Besides filtering high energy electrons near the extraction region, the magnetic filter field is clearly observed to increase the electron temperature in the heating region at low pressure discharge. With increasing the operating pressure, enhancement of electron temperature in the heating region is reduced. The possibility of electron cyclotron resonance (ECR) heating in the heating region due to stray magnetic field generated by a filter magnet located at the extraction region is examined. It is found that ECR heating by RF wave field in the discharge region, where the strength of an axial magnetic field is approximately ∼4.8 G, can effectively heat low energy electrons. Depletion of low energy electrons in the electron energy distribution function measured at the heating region supports the occurrence of ECR heating. The present study suggests that addition of axial magnetic field as small as several G by an external electromagnet or permanent magnets can greatly increase the generation of highly ro-vibrationally excited hydrogen molecules in the heating region, thus improving the performance of H{sup −} ion generation in volume-produced negative hydrogen ion sources.

  4. Equações de predição para estimar os valores da EMAn de alimentos proteicos para aves utilizando a meta-análise Prediction equations to estimate the AMEn values of protein feedstuffs for poultry utilizing meta-analysis

    Directory of Open Access Journals (Sweden)

    Germano Augusto Jerônimo do Nascimento

    2011-10-01

    Full Text Available Este trabalho foi realizado para se obter uma equação de predição para estimar os valores de energia metabolizável aparente corrigida (EMAn dos alimentos proteicos usualmente utilizados em rações para frangos de corte utilizando-se o princípio da meta-análise. Realizou-se uma revisão bibliográfica de estudos no Brasil para catalogar informações sobre valores de EMAn e composição química dos alimentos: proteína bruta (PB, extrato etéreo (EE, matéria mineral (MM, fibra bruta (FB, fibra em detergente neutro (FDN e fibra em detergente ácido (FDA. Foram considerados os efeitos de: sexo, em três níveis (macho, fêmea e mistos; idade, em quatro níveis (1ª e 2ª semana de vida, 3ª e 4ª semana, 5ª e 6ª semana e acima ou indefinido e metodologia empregada no metabolismo em dois níveis: coleta total (CT e alimentação forçada + (CT. Os dados foram analisados em um esquema fatorial 3 × 4 × 2, podendo totalizar até 24 grupos, adotando-se o procedimento Stepwise para a seleção de variáveis e o Proc Reg do (SAS para ajustar o modelo de regressão linear múltipla. A equação obtida que melhor se ajustou foi EMAn = 2707,71 + 58,63EE - 16,06FDN (R² = 0,81, sendo o EE a variável mais importante, em se tratando de possíveis variações nos teores energéticos dos alimentos proteicos.This study was accomplished aiming to obtain prediction equations to estimate the values of corrected apparent metabolizable energy (AMEn of the protein feedstuffs usually used in broiler rations, through the meta-analysis principle. Literature review of the studies realized in Brazil was performed to catalog information about values of AMEn and chemical composition of the feedstuffs reported (CP = crude protein; EE = ether extract; CF = crude fiber; NDF = neutral detergent fiber; ADF = acid detergent fiber. Effects of sex at three levels (male; female and mixed; age at four levels (1st and 2nd weeks of life; 3rd and 4th weeks; 5th and 6th weeks

  5. Neutron resonance spin echo with longitudinal DC fields

    Science.gov (United States)

    Krautloher, Maximilian; Kindervater, Jonas; Keller, Thomas; Häußler, Wolfgang

    2016-12-01

    We report on the design, construction, and performance of a neutron resonance spin echo (NRSE) instrument employing radio frequency (RF) spin flippers combining RF fields with DC fields, the latter oriented parallel (longitudinal) to the neutron propagation direction (longitudinal NRSE (LNRSE)). The advantage of the longitudinal configuration is the inherent homogeneity of the effective magnetic path integrals. In the center of the RF coils, the sign of the spin precession phase is inverted by a π flip of the neutron spins, such that non-uniform spin precession at the boundaries of the RF flippers is canceled. The residual inhomogeneity can be reduced by Fresnel- or Pythagoras-coils as in the case of conventional spin echo instruments (neutron spin echo (NSE)). Due to the good intrinsic homogeneity of the B0 coils, the current densities required for the correction coils are at least a factor of three less than in conventional NSE. As the precision and the current density of the correction coils are the limiting factors for the resolution of both NSE and LNRSE, the latter has the intrinsic potential to surpass the energy resolution of present NSE instruments. Our prototype LNRSE spectrometer described here was implemented at the resonance spin echo for diverse applications (RESEDA) beamline at the MLZ in Garching, Germany. The DC fields are generated by B0 coils, based on resistive split-pair solenoids with an active shielding for low stray fields along the beam path. One pair of RF flippers at a distance of 2 m generates a field integral of ˜0.5 Tm. The LNRSE technique is a future alternative for high-resolution spectroscopy of quasi-elastic excitations. In addition, it also incorporates the MIEZE technique, which allows to achieve spin echo resolution for spin depolarizing samples and sample environments. Here we present the results of numerical optimization of the coil geometry and first data from the prototype instrument.

  6. Field Notes

    Data.gov (United States)

    US Agency for International Development — This is a mobile application for capturing images , data, and geolocation for USAID projects in the field. The data is then stored on a server in AllNet. The...

  7. Tachyonic field interacting with scalar (phantom) field

    OpenAIRE

    Chattopadhyay, Surajit; Debnath, Ujjal

    2009-01-01

    In this letter, we have considered the universe is filled with the mixture of tachyonic field and scalar or phantom field. If the tachyonic field interacts with scalar or phantom field, the interaction term decays with time and the energy for scalar field is transferred to tachyonic field or the energy for phantom field is transferred to tachyonic field. The tachyonic field and scalar field potentials always decrease, but phantom field potential always increases.

  8. Simulation of remanent dose rates and benchmark measurements at the CERN-EU high energy reference field facility

    CERN Document Server

    Roesler, S; Donjoux, Y; Mitaroff, Angela

    2003-01-01

    A new approach is presented for the calculation of remanent dose rates from induced radioactivity with the FLUKA Monte-Carlo code. It is based on an explicit calculation of isotope production followed by the transport of photons, positrons, and electrons from the radioactive decay to the point of interest. The approach is benchmarked with a measurement in which samples of different materials were irradiated by the stray radiation field produced by interactions of high-energy hadrons in a copper target. Remanent dose rates were measured at different cooling times with a NaI scintillator-based survey instrument. The results of the simulations are generally in good agreement with the measurements. The method is applied to the prediction of remanent dose rates around the beam cleaning insertions of the LHC. 10 Refs.

  9. Discharge of water containing waste emanating from land to the ...

    African Journals Online (AJOL)

    driniev

    Abstract. The National Water Act, 1998 (Act 36 of 1998) mandates the Department of Water Affairs and Forestry to manage all water ... ground rules and management framework that will be applied to the discharge of land-derived wastewater to the marine ..... inventory of waste discharges to the marine environment, both in.

  10. Emanation of Formalistic Criticism Components in Nima Yushigs' "Khabe Zemestani"

    Directory of Open Access Journals (Sweden)

    Khalilollahi Shala

    2017-02-01

    Full Text Available Formalism is an approach and critical theory in which, form and structure are its essential elements of aesthetic considerations. Coleridge believes that form is a function of considered thoughts in poetry. From his point of view, form is achieved from inside the poem and by its' subject necessity. Nima abstains to directly explain his thoughts and emotions in "Khabe Zemestani" poem and symbolically proceeds to state his status and social events. The purpose of this article is the formalistic analysis of "Khabe Zemestani" poem from Nima Yushige. The issue of this paper is to explain the meaning and content of the poem "Khabe Zemestani" in the form and structure way, which has been done in library and content analysis method. The result of this analysis indicates that the most important motif in this poem is based on contrasts between "life and death", "sleep and wakefulness" and "neglect and soberness". Therefore, the main act of poem is based on divergence. In fact, contradictions, paradoxes and symbols in the poetry of Nima, have portrayed the main characters' condition and the social palpitation of his era with the help of nature elements.

  11. [After ten years of AIDS, a vision emanating from feminism].

    Science.gov (United States)

    Liguori, A L

    1991-01-01

    AIDS and the economic crisis in Mexico are threatening the epidemiologic transition in which infectious diseases ceased to be the only major cause of death and chronic degenerative diseases began to account for a growing proportion of deaths. Many factors combined to produce the sexual, gay, and women's liberation movements beginning in the 1970s. At the beginning of the feminist movement, women proposed different kinds of interpersonal relations both between women and with men. Women together realized their rights to control their own bodies, to sexual enjoyment, to abortion, and to free themselves of feelings of shame and guilt. The weight of moral pressures was lessened and the personal desires of the woman assumed a greater role in selection of sexual partners. Conservative forces grew stronger in the 1980s, and the proliferation of sexually transmitted diseases began to imperil the sexual revolution. But these setbacks were minor compared to AIDS. Now, 10 years after its appearance, it is clear that AIDS is not limited to homosexual men. The number of cases in Mexico increased from none 10 years ago to some 10,000 estimated cases reported and unreported today. 1/6 of the cases are in women. Many women and heterosexuals felt immune from AIDS in the beginning, and some still do, but many more have become aware of the danger. Women now fear contracting AIDS, but they also fear confronting their partners to suggest that they use condoms. Denial may play a role, but deeply rooted cultural factors that women may recognize but fee powerless to change may also be at play. Many women over 30 have difficulty taking the initiative in sexual matters. They are embarrassed to buy condoms and even more embarrassed to propose their use. They imagine that men will consider them "loose" if they carry condoms. Mexican women are poorly prepared to tell their men explicitly what they want sexually, and Mexican men are also poorly equipped to ask what women want, accustomed as they are to exercising sexuality exclusively to satisfy their own needs. The entire problem of condom use is related to ethical-moral and ideological factors and to broader attitudes toward knowledge. Those with more rational orientations see AIDS as a disease rather than a divine punishment and can more easily accept condom use as a preventive.

  12. Reproductive health issues emanating from the Children's Act No ...

    African Journals Online (AJOL)

    The study took as its point of departure the Children's Act No, 38 of 2005 implemented in 2010, which aims to promote the preservation and strengthening of families and to give effect to the rights of children as enshrined in the Constitution of the Republic of South Africa. When the Act was introduced certain segments of ...

  13. Emanations of the informational state: Cyber operations and the difficulties

    OpenAIRE

    Braman, Sandra

    2017-01-01

    >The Tallinn Manual of 2013 and its second edition, the Tallinn Manual 2.0 of 2017, are NATO-funded analyses of how existing international laws of war apply to cybersecurity and cyberwarfare. The difficulties faced by the groups of legal experts who produced these works often involve fundamental aspects of what it is to be a state altogether, challenging the survival of the state as a dominant political form altogether. These developments, in turn, provide significant challenges to the surviv...

  14. Discharge of water containing waste emanating from land to the ...

    African Journals Online (AJOL)

    driniev

    international Conventions and treaties such as the London Convention, is committed to certain requirements pertaining to the ... ground rules and management framework that will be applied to the discharge of land-derived wastewater to the marine ..... the risks to the environment in the event of malfunctioning, both.

  15. Stray animals: their impact on a community.

    Science.gov (United States)

    Griffiths, A O; Silberberg, A

    1975-04-01

    The statistical import of the study not-withstanding, we found the most serious problem to be the lack of understanding of the pet population crisis and compassion toward animals on the part of pet owners, as evident in the pet columns of the classified ads. Our study leads us to believe that pet owners are allowing the reproduction of kittens and puppies in such numbers that they often have no cash value and, in fact, the owners will spend money, in the form of advertising, to facilitate their disposal. The street observations indicated that relatively few animals (lessthan 1%) actually are allowed to run free. Dog bites occur at a ratio of 1:20 for the dog population. In the area under study, free roaming dogs and cats present a mild to moderate problem, originating from a small percentage of pet owners. Only a small amount of pet animal suffering occurs by death from environmental hazards (ie, automobiles), and there is just a moderate amount of intentional killing of nondersirable pet animals. We fell the method used in this study and the results obtained from it have importance elsewhere. It should be coupled with a broader based survey questionnaire to better establish the ratio of pet ownership to the general population and the reasons and benefits of pet ownership. We could then have the "facts" about the pet overpopulation problem, as well as better understand the community values toward pet animals. A complete report with additional accompanying tables is available from the senior author at Rural Route One, Urbana, Illinois 61801.

  16. Stray notes on Acarida (Arachnida) I

    NARCIS (Netherlands)

    Hammen, van der L.

    1968-01-01

    Since 1964 I have been publishing a series of extensive descriptions and morphological studies of various groups of mites. Although this type of work is rather time-devouring, it enlarges our knowledge considerably as to structures hitherto generally neglected. At the same time, however, we must not

  17. Topological fields

    CERN Document Server

    Warner, S

    1989-01-01

    Aimed at those acquainted with basic point-set topology and algebra, this text goes up to the frontiers of current research in topological fields (more precisely, topological rings that algebraically are fields).The reader is given enough background to tackle the current literature without undue additional preparation. Many results not in the text (and many illustrations by example of theorems in the text) are included among the exercises. Sufficient hints for the solution of the exercises are offered so that solving them does not become a major research effort for the reader. A comprehensive bibliography completes the volume.

  18. Field theory

    CERN Document Server

    Roman, Steven

    2006-01-01

    Intended for graduate courses or for independent study, this book presents the basic theory of fields. The first part begins with a discussion of polynomials over a ring, the division algorithm, irreducibility, field extensions, and embeddings. The second part is devoted to Galois theory. The third part of the book treats the theory of binomials. The book concludes with a chapter on families of binomials - the Kummer theory. This new edition has been completely rewritten in order to improve the pedagogy and to make the text more accessible to graduate students.  The exercises have also been im

  19. Inquérito sorológico sobre leishmaniose tegumentar americana em cães errantes no Estado de São Paulo, Brasil Serological survey for American cutaneous leishmaniasis in stray dogs in the S. Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    Elisa San Martin M Savani

    1999-12-01

    Full Text Available Inquérito sorológico para leishmaniose tegumentar americana em 973 cães errantes, capturados próximos a áreas verdes do Município de São Paulo, por meio da reação de imunofluorescência indireta, não demonstrou soros reagentes. No entanto, casos humanos autóctones dessa zoonose ocorridos no município indicam a circulação do parasita no ambiente. A existência de vetores e a aparente ausência de cães infectados nas áreas pesquisadas sugerem que o cão errante desempenhe papel irrelevante na disseminação do protozoário.A serological survey was made in 973 stray dogs caught near green areas in S. Paulo county by the indirect immunofluorescence test. No positive serum was found, however autochthonous human cases of ACL that occurred in the county show the circulation of the parasite in the environment. This fact, associated with the existence of the vectors and the apparent absence of infected dogs in the areas studied, suggest that stray dog plays an insignificant role in the spread of the parasite. The cycle of the parasite in São Paulo county has been maintained by wild animals, hence the dog would be an accidental host just as humans.

  20. Field Note

    African Journals Online (AJOL)

    Field Note. First Observation of the Slow Dragonet Callionymus aagilis Fricke,. 1999 in Its Natural Environment. M. Pinault1,2, A. Daydé3, R. Fricke4. 1USR 3278 CNRS-EPHE, CRIOBE & CBETM, University of Perpignan. 66860 Perpignan, France; 2Laboratory of Marine Ecology (ECOMAR), University of Reunion Island, ...

  1. Field Notes

    Science.gov (United States)

    Parrone, Edward G.; Montalto, Michael P.

    2008-01-01

    The importance of athletic fields has increased in today's society because of the popularity of sporting events. As a result, education administrators face challenges when dealing with their athletic facilities. Decisionmakers constantly are being second-guessed in regard to outdated, overused facilities and lack of budget. In this article, the…

  2. Field theory

    CERN Multimedia

    1999-11-08

    In these lectures I will build up the concept of field theory using the language of Feynman diagrams. As a starting point, field theory in zero spacetime dimensions is used as a vehicle to develop all the necessary techniques: path integral, Feynman diagrams, Schwinger-Dyson equations, asymptotic series, effective action, renormalization etc. The theory is then extended to more dimensions, with emphasis on the combinatorial aspects of the diagrams rather than their particular mathematical structure. The concept of unitarity is used to, finally, arrive at the various Feynman rules in an actual, four-dimensional theory. The concept of gauge-invariance is developed, and the structure of a non-abelian gauge theory is discussed, again on the level of Feynman diagrams and Feynman rules.

  3. Field Centipedes

    OpenAIRE

    Ignacio Palacios-Huerta; Oscar Volij

    2009-01-01

    In the centipede game, all standard equilibrium concepts dictate that the player who decides first must stop the game immediately. There is vast experimental evidence, however, that this rarely occurs. We first conduct a field experiment in which highly ranked chess players play this game. Contrary to previous evidence, our results show that69 percent of chess players stop immediately. When we restrict attention to Grandmasters, this percentage escalates to 100 percent. We then conduct a labo...

  4. Far Field Extrapolation from Near Field Interactions and Shielding Influence Investigations Based on a FE-PEEC Coupling Method

    Directory of Open Access Journals (Sweden)

    Gérard Meunier

    2013-03-01

    Full Text Available Regarding standards, it is well established that common mode currents are the main source of far field emitted by variable frequency drive (VFD-cable-motor associations. These currents are generated by the combination of floating potentials with stray capacitances between these floating potential tracks and the mechanical parts connected to the earth (the heatsink or cables are usual examples. Nowadays, due to frequency and power increases, the systematic compliance to EMC (ElectroMagnetic Compatibility becomes increasingly difficult and costly for industrials. As a consequence, there is a well-identified need to investigate practical and low cost solutions to reduce the radiated fields of VFD-cable-motor associations. A well-adapted solution is the shielding of wound components well known as the major source of near magnetic field. However, this solution is not convenient, it is expensive and may not be efficient regarding far field reduction. Optimizing the components placement could be a better and cheaper solution. As a consequence, dedicated tools have to be developed to efficiently investigate not easy comprehendible phenomena and finally to control EMC disturbances using component placement, layout geometry, shielding design if needed. However, none of the modeling methods usually used in industry complies with large frequency range and far field models including magnetic materials, multilayer PCBs, and shielding. The contribution of this paper is to show that alternatives regarding modeling solutions exist and can be used to get in-deep analysis of such complex structures. It is shown in this paper that near field investigations can give information on far field behavior. It is illustrated by an investigation of near field interactions and shielding influence using a FE-PEEC hybrid method. The test case combining a common mode filter with the floating potentials tracks of an inverter is based on an industrial and commercialized VFD. The

  5. MULTI-WAVELENGTH STUDY OF A DELTA-SPOT. I. A REGION OF VERY STRONG, HORIZONTAL MAGNETIC FIELD

    Energy Technology Data Exchange (ETDEWEB)

    Jaeggli, S. A., E-mail: sarah.jaeggli@nasa.gov [NASA Goddard Space Flight Center, Solar Physics Laboratory, Code 671, Greenbelt, MD 20771 (United States)

    2016-02-10

    Active region NOAA 11035 appeared in 2009 December, early in the new solar activity cycle. This region achieved a delta sunspot (δ spot) configuration when parasitic flux emerged near the rotationally leading magnetic polarity and traveled through the penumbra of the largest sunspot in the group. Both visible and infrared imaging spectropolarimetry of the magnetically sensitive Fe i line pairs at 6302 and 15650 Å show large Zeeman splitting in the penumbra between the parasitic umbra and the main sunspot umbra. The polarized Stokes spectra in the strongest field region display anomalous profiles, and strong blueshifts are seen in an adjacent region. Analysis of the profiles is carried out using a Milne–Eddington inversion code capable of fitting either a single magnetic component with stray light or two independent magnetic components to verify the field strength. The inversion results show that the anomalous profiles cannot be produced by the combination of two profiles with moderate magnetic fields. The largest field strengths are 3500–3800 G in close proximity to blueshifts as strong as 3.8 km s{sup −1}. The strong, nearly horizontal magnetic field seen near the polarity inversion line in this region is difficult to understand in the context of a standard model of sunspot magnetohydrostatic equilibrium.

  6. Nucleation and interactions of 360∘ domain walls on planar ferromagnetic nanowires using circular magnetic fields

    Directory of Open Access Journals (Sweden)

    F. I. Kaya

    2016-05-01

    Full Text Available We propose a mechanism for nucleation of 360∘ domain walls (DWs on planar ferromagnetic nanowires, of 100 nm width, by using circular magnetic fields, and find the minimal spacing possible between 360∘ DWs. The extent of the stray field from a 360∘ DW is limited in comparison to 180∘ DWs, allowing 360∘ DWs to be spaced more closely without interactions than 180∘ DWs, which is potentially useful for data storage devices. We use micromagnetic simulations to demonstrate the positioning of 360∘ DWs, using a series of rectangular 16 × 16 nm2 notches to act as local pinning sites on the nanowires. For these notches, the minimum spacing between the DWs is 240 nm, corresponding to a 360∘ DW packing density of 4 DWs per micron. Understanding the topological properties of the 360∘ DWs allows us to understand their formation and annihilation in the proposed geometry. Adjacent 360∘ DWs have opposite circulation, and closer spacing results in the adjacent walls breaking into 180∘ DWs and annihilating.

  7. Electric field-triggered metal-insulator transition resistive switching of bilayered multiphasic VOx

    Science.gov (United States)

    Won, Seokjae; Lee, Sang Yeon; Hwang, Jungyeon; Park, Jucheol; Seo, Hyungtak

    2017-10-01

    Electric field-triggered Mott transition of VO2 for next-generation memory devices with sharp and fast resistance-switching response is considered to be ideal but the formation of single-phase VO2 by common deposition techniques is very challenging. Here, VOx films with a VO2-dominant phase for a Mott transition-based metal-insulator transition (MIT) switching device were successfully fabricated by the combined process of RF magnetron sputtering of V metal and subsequent O2 annealing to form. By performing various material characterizations, including scanning transmission electron microscopyelectron energy loss spectroscopy, the film is determined to have a bilayer structure consisting of a VO2-rich bottom layer acting as the Mott transition switching layer and a V2O5/V2O3 mixed top layer acting as a control layer that suppresses any stray leakage current and improves cyclic performance. This bilayer structure enables excellent electric field-triggered Mott transition-based resistive switching of Pt- VOx-Pt metal-insulator-metal devices with a set/reset current ratio reaching 200, set/reset voltage of less than 2.5 V, and very stable DC cyclic switching upto 120 cycles with a great set/reset current and voltage distribution less than 5% of standard deviation at room temperature, which are specifications applicable for neuromorphic or memory device applications.[Figure not available: see fulltext.

  8. Electric field-triggered metal-insulator transition resistive switching of bilayered multiphasic VOx

    Science.gov (United States)

    Won, Seokjae; Lee, Sang Yeon; Hwang, Jungyeon; Park, Jucheol; Seo, Hyungtak

    2018-01-01

    Electric field-triggered Mott transition of VO2 for next-generation memory devices with sharp and fast resistance-switching response is considered to be ideal but the formation of single-phase VO2 by common deposition techniques is very challenging. Here, VOx films with a VO2-dominant phase for a Mott transition-based metal-insulator transition (MIT) switching device were successfully fabricated by the combined process of RF magnetron sputtering of V metal and subsequent O2 annealing to form. By performing various material characterizations, including scanning transmission electron microscopy-electron energy loss spectroscopy, the film is determined to have a bilayer structure consisting of a VO2-rich bottom layer acting as the Mott transition switching layer and a V2O5/V2O3 mixed top layer acting as a control layer that suppresses any stray leakage current and improves cyclic performance. This bilayer structure enables excellent electric field-triggered Mott transition-based resistive switching of Pt-VOx-Pt metal-insulator-metal devices with a set/reset current ratio reaching 200, set/reset voltage of less than 2.5 V, and very stable DC cyclic switching upto 120 cycles with a great set/reset current and voltage distribution less than 5% of standard deviation at room temperature, which are specifications applicable for neuromorphic or memory device applications. [Figure not available: see fulltext.

  9. Aperture and Field Constraints for the Vacuum System in the LHC Injection Septa

    CERN Document Server

    Gyr, Marcel; Jiménez, J M; Lacroix, Jean Michel; Sgobba, Stefano

    2005-01-01

    Each beam arriving from the SPS has to pass through five injection septum magnets before being kicked onto the LHC orbit. The injection layout implies that the vacuum chambers for the two circulating beams pass through the septum magnet yokes at a flange distance from the chamber of the beam to be injected. Specially designed vacuum chambers and interconnections provide the required straightness and alignment precision, thus optimising the aperture for both the circulating and injected beams, without affecting the quality of the magnetic dipole field seen by the injected beam. The circulating beams are shielded against the magnetic stray field by using µ-metal chambers with a thickness of 0.9 mm to avoid saturation of the µ-metal (0.8 T), coated with copper (0.4 mm) for impedance reasons and NEG for pumping and electron cloud purposes. A 2 mm gap between the iron yoke and the µ-metal chamber allows an in-situ bake-out at 200°C, based on a polyimide/stainless steel/polyimide sandwich structure with an over...

  10. Measurements of periodically electric field from the interior of the earth

    Directory of Open Access Journals (Sweden)

    J. M. Tsatsaragos

    2008-01-01

    Full Text Available This paper presents electric field measurements in the underground water horizon that have been processed by a specialised model installation which receives and records electric signals. From the description and the technical characteristics of the installation, it results that the origin of changes of the recorded electric field is owed to a natural process that concerns the interior of our planet. External factors such as the Ionosphere and human activity do not interfere with the measurements of this particular installation.The presentation of the measurements is dominated by a permanent periodic variation of the electric field with a constant period of about 24 hours. The basic periodic variation of the electric component, which is recorded and examined here, is modulated by pulses of variable amplitude and duration, accidentally distributed in time. The possible generating mechanism of pulses is also under examination in this paper. The result of spectrum analysis of the initial recordings shows a high peak which is identified with the equivalent maximum of the two main mechanical tidal components that are described in the bibliography. It is under examination whether the measured changes are related or emanating from the tidal deformity of the ground.Other available measurements of the components of the Earth’s magnetic field (included in the measurements carried out by special scientific projects in Greece and around the world show the existence of a permanent periodic variation with a constant period of about 24 hours. The time comparison between the variations of the vertical component of the Earth’s magnetic field and the measured variations of the electric field reveals a phase shift of 90 degrees.Taking into consideration the above statement, we may infer that the periodic variation of the measured electric signal is the electric component of an electromagnetic wave. It appears that this electromagnetic wave is caused by the

  11. Physics-based modeling of power system components for the evaluation of low-frequency radiated electromagnetic fields

    Science.gov (United States)

    Barzegaranbaboli, Mohammadreza

    verified experimentally. Finally, the identification of the types of power components were implemented. The results show that it is possible to identify the type of components, as well as the faulty components, by comparing the amplitudes of their stray field harmonics. The identification using the stray fields is nondestructive and can be used for the setups that cannot go offline and be dismantled.

  12. Flow dynamics at a river confluence on Mississippi River: field measurement and large eddy simulation

    Science.gov (United States)

    Le, Trung; Khosronejad, Ali; Bartelt, Nicole; Woldeamlak, Solomon; Peterson, Bonnie; Dewall, Petronella; Sotiropoulos, Fotis; Saint Anthony Falls Laboratory, University of Minnesota Team; Minnesota Department of Transportation Team

    2015-11-01

    We study the dynamics of a river confluence on Mississippi River branch in the city of Minneapolis, Minnesota, United States. Field measurements by Acoustic Doppler Current Profiler using on-board GPS tracking were carried out for five campaigns in the summer of 2014 and 2015 to collect both river bed elevation data and flow fields. Large Eddy Simulation is carried out to simulate the flow field with the total of 100 million grid points for the domain length of 3.2 km. The simulation results agree well with field measurements at measured cross-sections. The results show the existence of wake mode on the mixing interface of two branches near the upstream junction corner. The mutual interaction between the shear layers emanating from the river banks leading to the formation of large scale energetic structures that leads to ``switching'' side of the flow coherent structures. Our result here is a feasibility study for the use of eddy-resolving simulations in predicting complex flow dynamics in medium-size natural rivers. This work is funded by Minnesota Dept. Transportation and Minnesota Institute of Supercomputing.

  13. Visualization of the funis of Giardia lamblia by high-resolution field emission scanning electron microscopy--new insights.

    Science.gov (United States)

    Benchimol, Marlene; Piva, Bruno; Campanati, Loraine; de Souza, Wanderley

    2004-08-01

    Giardia lamblia is a multiflagellar parasite and one of the earliest diverging eukaryotic cells. It possesses a cytoskeleton made of several microtubular structures-an adhesive disc, four pairs of flagella, median body, and funis. This protozoan displays different types of movements, including a lateral and dorso-ventral dislocation of its posterior region, which has not been completely elucidated. In the present study, high-resolution field emission scanning electron microscopy was used to analyze the funis structure of G. lamblia trophozoites. It was shown that the funis is made of short arrays of microtubules emanating from the axonemes of the caudal flagella, which are anchored to dense rods that run parallel to the posterior-lateral flagella. After emergence of the posterior-lateral flagella, funis microtubules are anchored to the epiplasm, a fibrous layer that underlies the portion of membrane that presents tail contractility. Based on these observations a model for the tail flexion of G. lamblia is proposed.

  14. Field-free deterministic ultrafast creation of magnetic skyrmions by spin-orbit torques.

    Science.gov (United States)

    Büttner, Felix; Lemesh, Ivan; Schneider, Michael; Pfau, Bastian; Günther, Christian M; Hessing, Piet; Geilhufe, Jan; Caretta, Lucas; Engel, Dieter; Krüger, Benjamin; Viefhaus, Jens; Eisebitt, Stefan; Beach, Geoffrey S D

    2017-11-01

    Magnetic skyrmions are stabilized by a combination of external magnetic fields, stray field energies, higher-order exchange interactions and the Dzyaloshinskii-Moriya interaction (DMI). The last favours homochiral skyrmions, whose motion is driven by spin-orbit torques and is deterministic, which makes systems with a large DMI relevant for applications. Asymmetric multilayers of non-magnetic heavy metals with strong spin-orbit interactions and transition-metal ferromagnetic layers provide a large and tunable DMI. Also, the non-magnetic heavy metal layer can inject a vertical spin current with transverse spin polarization into the ferromagnetic layer via the spin Hall effect. This leads to torques that can be used to switch the magnetization completely in out-of-plane magnetized ferromagnetic elements, but the switching is deterministic only in the presence of a symmetry-breaking in-plane field. Although spin-orbit torques led to domain nucleation in continuous films and to stochastic nucleation of skyrmions in magnetic tracks, no practical means to create individual skyrmions controllably in an integrated device design at a selected position has been reported yet. Here we demonstrate that sub-nanosecond spin-orbit torque pulses can generate single skyrmions at custom-defined positions in a magnetic racetrack deterministically using the same current path as used for the shifting operation. The effect of the DMI implies that no external in-plane magnetic fields are needed for this aim. This implementation exploits a defect, such as a constriction in the magnetic track, that can serve as a skyrmion generator. The concept is applicable to any track geometry, including three-dimensional designs.

  15. Field-free deterministic ultrafast creation of magnetic skyrmions by spin-orbit torques

    Science.gov (United States)

    Büttner, Felix; Lemesh, Ivan; Schneider, Michael; Pfau, Bastian; Günther, Christian M.; Hessing, Piet; Geilhufe, Jan; Caretta, Lucas; Engel, Dieter; Krüger, Benjamin; Viefhaus, Jens; Eisebitt, Stefan; Beach, Geoffrey S. D.

    2017-11-01

    Magnetic skyrmions are stabilized by a combination of external magnetic fields, stray field energies, higher-order exchange interactions and the Dzyaloshinskii-Moriya interaction (DMI). The last favours homochiral skyrmions, whose motion is driven by spin-orbit torques and is deterministic, which makes systems with a large DMI relevant for applications. Asymmetric multilayers of non-magnetic heavy metals with strong spin-orbit interactions and transition-metal ferromagnetic layers provide a large and tunable DMI. Also, the non-magnetic heavy metal layer can inject a vertical spin current with transverse spin polarization into the ferromagnetic layer via the spin Hall effect. This leads to torques that can be used to switch the magnetization completely in out-of-plane magnetized ferromagnetic elements, but the switching is deterministic only in the presence of a symmetry-breaking in-plane field. Although spin-orbit torques led to domain nucleation in continuous films and to stochastic nucleation of skyrmions in magnetic tracks, no practical means to create individual skyrmions controllably in an integrated device design at a selected position has been reported yet. Here we demonstrate that sub-nanosecond spin-orbit torque pulses can generate single skyrmions at custom-defined positions in a magnetic racetrack deterministically using the same current path as used for the shifting operation. The effect of the DMI implies that no external in-plane magnetic fields are needed for this aim. This implementation exploits a defect, such as a constriction in the magnetic track, that can serve as a skyrmion generator. The concept is applicable to any track geometry, including three-dimensional designs.

  16. The wide field imager instrument for Athena

    Science.gov (United States)

    Meidinger, Norbert; Eder, Josef; Eraerds, Tanja; Nandra, Kirpal; Pietschner, Daniel; Plattner, Markus; Rau, Arne; Strecker, Rafael

    2016-07-01

    The WFI (Wide Field Imager) instrument is planned to be one of two complementary focal plane cameras on ESA's next X-ray observatory Athena. It combines unprecedented survey power through its large field of view of 40 amin x 40 amin together with excellent count rate capability (>= 1 Crab). The energy resolution of the silicon sensor is state-of-the-art in the energy band of interest from 0.2 keV to 15 keV, e.g. the full width at half maximum of a line at 7 keV will be MOSFET integrated onto a fully depleted 450 μm thick silicon bulk. Two detectors are planned for the WFI instrument: A large-area detector comprising four sensors with a total of 1024 x 1024 pixels and a fast detector optimized for high count rate observations. This high count rate capable detector permits for bright point sources with an intensity of 1 Crab a throughput of more than 80% and a pile-up of less than 1%. The fast readout of the DEPFET pixel matrices is facilitated by an ASIC development, called VERITAS-2. Together with the Switcher-A, a control ASIC that allows for operation of the DEPFET in rolling shutter mode, these elements form the key components of the WFI detectors. The detectors are surrounded by a graded-Z shield, which has in particular the purpose to avoid fluorescence lines that would contribute to the instrument background. Together with ultra-thin coating of the sensor and particle identification by the detector itself, the particle induced background shall be minimized in order to achieve the scientific requirement of a total instrumental background value smaller than 5 x 10-3 cts/cm2/s/keV. Each detector has its dedicated detector electronics (DE) for supply and data acquisition. Due to the high frame rate in combination with the large pixel array, signal correction and event filtering have to be done on-board and in real-time as the raw data rate would by far exceed the feasible telemetry rate. The data streams are merged and compressed in the Instrument Control and

  17. Electromagnetic fields from two potential fields

    Science.gov (United States)

    Chauca, J.; Doria, R.; Soares, W.

    2012-10-01

    Maxwell electromagnetism is generalized through a model that includes N-potential fields in a same group. Anew rule for the photon field is defined from a fourth interpretation to the light invariance. It becomes a directive particle while others potential fields appears as circumstance particles. Its most primitive coupling is not more with electric charge but with the Noether systemic charge. Studying the case with two potential fields, one derives the corresponding granular and collective electromagnetic fields with antisymmetric and symmetric nature. As a first feature, differently from Maxwell equation such systemic photon field does not follow the expression inversely proportional to the distance. This work calculates the subsequent branch of elecromagnetic fields {→EI-→BI,→e-→b;ɛI,→ɛI,βIij,s,→s,sij}.

  18. Low-temperature high magnetic field powder x-ray diffraction setup for field-induced structural phase transition studies from 2 to 300 K and at 0 to 8-T field

    Science.gov (United States)

    Shahee, Aga; Sharma, Shivani; Kumar, Dhirendra; Yadav, Poonam; Bhardwaj, Preeti; Ghodke, Nandkishor; Singh, Kiran; Lalla, N. P.; Chaddah, P.

    2016-10-01

    A low-temperature and high magnetic field powder x-ray diffractometer (XRD) has been developed at UGC-DAE CSR (UGC: University Grant Commission, DAE: Department of Atomic Energy, and CSR: Consortium for scientific research), Indore, India. The setup has been developed around an 18 kW rotating anode x-ray source delivering Cu-Kα x-rays coming from a vertical line source. It works in a symmetric θ-2θ parallel beam geometry. It consists of a liquid helium cryostat with an 8 T split-pair Nb-Ti superconducting magnet comprising two x-ray windows each covering an angular range of 65°. This is mounted on a non-magnetic type heavy duty goniometer equipped with all necessary motions along with data collection accessories. The incident x-ray beam has been made parallel using a parabolic multilayer mirror. The scattered x-ray is detected using a NaI detector through a 0.1° acceptance solar collimator. To control the motions of the goniometer, a computer programme has been developed. The wide-angle scattering data can be collected in a range of 2°-115° of 2θ with a resolution of ˜0.1°. The whole setup is tightly shielded for the scattered x-rays using a lead hutch. The functioning of the goniometer and the artifacts arising possibly due to the effect of stray magnetic field on the goniometer motions, on the x-ray source, and on the detector have been characterized by collecting powder XRD data of a National Institute of Standards and Technology certified standard reference material LaB6 (SRM-660b) and Si powder in zero-field and in-field conditions. Occurrence of field induced structural-phase transitions has been demonstrated on various samples like Pr0.5Sr0.5MnO3, Nd0.49Sr0.51MnO3-δ and La0.175Pr0.45Ca0.375MnO3 by collecting data in zero field cool and field cool conditions.

  19. Low-temperature high magnetic field powder x-ray diffraction setup for field-induced structural phase transition studies from 2 to 300 K and at 0 to 8-T field.

    Science.gov (United States)

    Shahee, Aga; Sharma, Shivani; Kumar, Dhirendra; Yadav, Poonam; Bhardwaj, Preeti; Ghodke, Nandkishor; Singh, Kiran; Lalla, N P; Chaddah, P

    2016-10-01

    A low-temperature and high magnetic field powder x-ray diffractometer (XRD) has been developed at UGC-DAE CSR (UGC: University Grant Commission, DAE: Department of Atomic Energy, and CSR: Consortium for scientific research), Indore, India. The setup has been developed around an 18 kW rotating anode x-ray source delivering Cu-Kα x-rays coming from a vertical line source. It works in a symmetric θ-2θ parallel beam geometry. It consists of a liquid helium cryostat with an 8 T split-pair Nb-Ti superconducting magnet comprising two x-ray windows each covering an angular range of 65°. This is mounted on a non-magnetic type heavy duty goniometer equipped with all necessary motions along with data collection accessories. The incident x-ray beam has been made parallel using a parabolic multilayer mirror. The scattered x-ray is detected using a NaI detector through a 0.1° acceptance solar collimator. To control the motions of the goniometer, a computer programme has been developed. The wide-angle scattering data can be collected in a range of 2°-115° of 2θ with a resolution of ∼0.1°. The whole setup is tightly shielded for the scattered x-rays using a lead hutch. The functioning of the goniometer and the artifacts arising possibly due to the effect of stray magnetic field on the goniometer motions, on the x-ray source, and on the detector have been characterized by collecting powder XRD data of a National Institute of Standards and Technology certified standard reference material LaB6 (SRM-660b) and Si powder in zero-field and in-field conditions. Occurrence of field induced structural-phase transitions has been demonstrated on various samples like Pr0.5Sr0.5MnO3, Nd0.49Sr0.51MnO3-δ and La0.175Pr0.45Ca0.375MnO3 by collecting data in zero field cool and field cool conditions.

  20. Measurements of intermediate-frequency electric and magnetic fields in households.

    Science.gov (United States)

    Aerts, Sam; Calderon, Carolina; Valič, Blaž; Maslanyj, Myron; Addison, Darren; Mee, Terry; Goiceanu, Cristian; Verloock, Leen; Van den Bossche, Matthias; Gajšek, Peter; Vermeulen, Roel; Röösli, Martin; Cardis, Elisabeth; Martens, Luc; Joseph, Wout

    2017-04-01

    Historically, assessment of human exposure to electric and magnetic fields has focused on the extremely-low-frequency (ELF) and radiofrequency (RF) ranges. However, research on the typically emitted fields in the intermediate-frequency (IF) range (300Hz to 1MHz) as well as potential effects of IF fields on the human body remains limited, although the range of household appliances with electrical components working in the IF range has grown significantly (e.g., induction cookers and compact fluorescent lighting). In this study, an extensive measurement survey was performed on the levels of electric and magnetic fields in the IF range typically present in residences as well as emitted by a wide range of household appliances under real-life circumstances. Using spot measurements, residential IF field levels were found to be generally low, while the use of certain appliances at close distance (20cm) may result in a relatively high exposure. Overall, appliance emissions contained either harmonic signals, with fundamental frequencies between 6kHz and 300kHz, which were sometimes accompanied by regions in the IF spectrum of rather noisy, elevated field strengths, or much more capricious spectra, dominated by 50Hz harmonics emanating far in the IF domain. The maximum peak field strengths recorded at 20cm were 41.5V/m and 2.7A/m, both from induction cookers. Finally, none of the appliance emissions in the IF range exceeded the exposure summation rules recommended by the International Commission on Non-Ionizing Radiation Protection guidelines and the International Electrotechnical Commission (IEC 62233) standard at 20cm and beyond (maximum exposure quotients EQE 1.0 and EQH 0.13). Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Magnetic Field Calculator

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Magnetic Field Calculator will calculate the total magnetic field, including components (declination, inclination, horizontal intensity, northerly intensity,...

  2. How fields vary.

    Science.gov (United States)

    Krause, Monika

    2017-04-06

    Field theorists have long insisted that research needs to pay attention to the particular properties of each field studied. But while much field-theoretical research is comparative, either explicitly or implicitly, scholars have only begun to develop the language for describing the dimensions along which fields can be similar to and different from each other. In this context, this paper articulates an agenda for the analysis of variable properties of fields. It discusses variation in the degree but also in the kind of field autonomy. It discusses different dimensions of variation in field structure: fields can be more or less contested, and more or less hierarchical. The structure of symbolic oppositions in a field may take different forms. Lastly, it analyses the dimensions of variation highlighted by research on fields on the sub- and transnational scale. Post-national analysis allows us to ask how fields relate to fields of the same kind on different scales, and how fields relate to fields on the same scale in other national contexts. It allows us to ask about the role resources from other scales play in structuring symbolic oppositions within fields. A more fine-tuned vocabulary for field variation can help us better describe particular fields and it is a precondition for generating hypotheses about the conditions under which we can expect to observe fields with specified characteristics. © London School of Economics and Political Science 2017.

  3. The Effect of Magnetic Field on HTS Leads What Happens when thePower Fails at RAL?

    Energy Technology Data Exchange (ETDEWEB)

    Green, Michael A.

    2007-02-14

    The key to being able to operate the MICE superconducting solenoids on small coolers is the use of high temperature superconducting (HTS) leads between the first stage of the cooler and the magnet, which operates at around 4.2 K. Because MICE magnets are not shielded, all of the MICE magnets have a stray magnetic field in the region where the coolers and the HTS leads are located. The behavior of the HTS leads in a magnetic field depends strongly on the HTS material used for the leads and the temperature of the cooler first stage temperature. The HTS leads can be specified to operate at the maximum current for the magnet. This report shows how the HTS leads can be specified for use the MICE magnets. MICE magnets take from 1.3 hours (the tracker solenoids) to 3.7 hours (the coupling magnet) to charge to the highest projected operating currents. If the power fails, the cooler and the upper ends of the HTS leads warm up. The question is how one can discharge the magnet to protect the HTS leads without quenching the MICE magnets. This report describes a method that one can use to protect the HTS leads in the event of a power failure at the Rutherford Appleton Laboratory (RAL).

  4. Phase Field Approach

    Science.gov (United States)

    Koyama, Toshiyuki

    The term phase field has recently become known across many fields of materials science. The meaning of phase field is the spatial and temporal order parameter field defined in a continuum-diffused interface model. By using the phase field order parameters, many types of complex microstructure changes observed in materials science are described effectively. This methodology has been referred to as the phase field method, phase field simulation, phase field modeling, phase field approach, etc. In this chapter, the basic concept and theoretical background for the phase field approach is explained in Sects. 21.1 and 21.2. The overview of recent applications of the phase field method is demonstrated in Sects. 21.3 to 21.6.

  5. Analysis on optical heterodyne frequency error of full-field heterodyne interferometer

    Science.gov (United States)

    Li, Yang; Zhang, Wenxi; Wu, Zhou; Lv, Xiaoyu; Kong, Xinxin; Guo, Xiaoli

    2017-06-01

    The full-field heterodyne interferometric measurement technology is beginning better applied by employing low frequency heterodyne acousto-optical modulators instead of complex electro-mechanical scanning devices. The optical element surface could be directly acquired by synchronously detecting the received signal phases of each pixel, because standard matrix detector as CCD and CMOS cameras could be used in heterodyne interferometer. Instead of the traditional four-step phase shifting phase calculating, Fourier spectral analysis method is used for phase extracting which brings lower sensitivity to sources of uncertainty and higher measurement accuracy. In this paper, two types of full-field heterodyne interferometer are described whose advantages and disadvantages are also specified. Heterodyne interferometer has to combine two different frequency beams to produce interference, which brings a variety of optical heterodyne frequency errors. Frequency mixing error and beat frequency error are two different kinds of inescapable heterodyne frequency errors. In this paper, the effects of frequency mixing error to surface measurement are derived. The relationship between the phase extraction accuracy and the errors are calculated. :: The tolerance of the extinction ratio of polarization splitting prism and the signal-to-noise ratio of stray light is given. The error of phase extraction by Fourier analysis that caused by beat frequency shifting is derived and calculated. We also propose an improved phase extraction method based on spectrum correction. An amplitude ratio spectrum correction algorithm with using Hanning window is used to correct the heterodyne signal phase extraction. The simulation results show that this method can effectively suppress the degradation of phase extracting caused by beat frequency error and reduce the measurement uncertainty of full-field heterodyne interferometer.

  6. Experimental and theoretical investigation of the magnetization dynamics of an artificial square spin ice cluster

    Energy Technology Data Exchange (ETDEWEB)

    Pohlit, Merlin, E-mail: pohlit@physik.uni-frankfurt.de; Porrati, Fabrizio; Huth, Michael; Müller, Jens [Institute of Physics, Goethe-University Frankfurt, Frankfurt/Main (Germany); Stockem, Irina; Schröder, Christian [Bielefeld Institute for Applied Materials Research, FH Bielefeld-University of Applied Sciences, Bielefeld (Germany)

    2016-10-14

    We study the magnetization dynamics of a spin ice cluster which is a building block of an artificial square spin ice fabricated by focused electron-beam-induced deposition both experimentally and theoretically. The spin ice cluster is composed of twelve interacting Co nanoislands grown directly on top of a high-resolution micro-Hall sensor. By employing micromagnetic simulations and a macrospin model, we calculate the magnetization and the experimentally investigated stray field emanating from a single nanoisland. The parameters determined from a comparison with the experimental hysteresis loop are used to derive an effective single-dipole macrospin model that allows us to investigate the dynamics of the spin ice cluster. Our model reproduces the experimentally observed non-deterministic sequences in the magnetization curves as well as the distinct temperature dependence of the hysteresis loop.

  7. Field Campaign Guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Voyles, J. W. [DOE ARM Climate Research Facility, Washington, DC (United States); Chapman, L. A. [DOE ARM Climate Research Facility, Washington, DC (United States)

    2015-12-01

    This document establishes a common set of guidelines for the Atmospheric Radiation Measurement (ARM) Climate Research Facility for planning, executing, and closing out field campaigns. The steps that guide individual field campaigns are described in the Field Campaign Tracking System and are specifically tailored to meet the scope of each field campaign.

  8. Cell-cycle kinetics of Friend erythroleukemia cells in a magnetically shielded room and in a low-frequency/low-intensity magnetic field.

    Science.gov (United States)

    Eremenko, T; Esposito, C; Pasquarelli, A; Pasquali, E; Volpe, P

    1997-01-01

    This work was undertaken to compare the behavior of Friend erythroleukemia cells in a solenoid, where the magnetic field was 70 microT at 50 Hz (plus 45 microT DC of Earth) with that of the same cells in a magnetically shielded room, where the magnetic field was attenuated to 20 nT DC and 2.5 pT AC. The control laboratory magnetic field corresponded to 45 microT DC and a stray 50 Hz field below 0.2 microT. The culture growth cycle of cells maintained inside the solenoid was slightly accelerated compared with that of cells maintained outside the solenoid (P magnetic field, because, inside the solenoid, the percentage of G1 cells slightly increased during the culture growth cycle, whereas that of S cells slightly decreased. Acceleration of growth was detected soon after exposure of the cultures to the solenoid field, and growth did not change further if the action of this field continued for a long time, accounting for adaptation. The solenoid field also caused a small increase of cell survival without influencing cell volume. By contrast, the culture growth cycle of cells maintained inside the magnetically shielded room was slightly decelerated compared with that of cells maintained outside the room (P field inside the magnetically shielded room also caused a small increase of cell volume, whereas, during the culture growth cycle, the percentage of G1 cells decreased, and that of S cells increased. The majority of these events did not change in cells induced to differentiate hemoglobin through dimethylsulfoxide.

  9. An analysis of the radiation from apertures in curved surfaces by the geometrical theory of diffraction. [ray technique for electromagnetic fields

    Science.gov (United States)

    Pathak, P. H.; Kouyoumjian, R. G.

    1974-01-01

    In this paper the geometrical theory of diffraction is extended to treat the radiation from apertures of slots in convex perfectly conducting surfaces. It is assumed that the tangential electric field in the aperture is known so that an equivalent infinitesimal source can be defined at each point in the aperture. Surface rays emanate from this source which is a caustic of the ray system. A launching coefficient is introduced to describe the excitation of the surface ray modes. If the field radiated from the surface is desired, the ordinary diffraction coefficients are used to determine the field of the rays shed tangentially from the surface rays. The field of the surface ray modes is not the field on the surface; hence if the mutual coupling between slots is of interest, a second coefficient related to the launching coefficient must be employed. In the region adjacent to the shadow boundary, the component of the field directly radiated from the source is represented by Fock-type functions. In the illuminated region the incident radiation from the source (this does not include the diffracted field components) is treated by geometrical optics. This extension of the geometrical theory of diffraction is applied to calculate the radiation from slots on elliptic cylinders, spheres, and spheroids.

  10. Irregular magnetohydrodynamic shock refraction in the presence of a normal magnetic field

    Science.gov (United States)

    Wheatley, Vincent; Bilgi, Pavaman; Samtaney, Ravi; Pullin, Dale

    2015-11-01

    Shock refraction occurs when an incident shock encounters a density interface, which is important in a number of applications. When all waves resulting from the interaction meet at a point, this is termed regular shock refraction. In magnetohydrodynamics, analytical solutions for regular refraction cases show that magnetohydrodynamic waves transport vorticity from the shocked density interface so that it is not a shear layer. This is the mechanism that underpins the suppression of shock driven instabilities in the presence of a magnetic field. Here, we examine the case of irregular shock refraction where the initial magnetic field is normal to the incident shock. Regular analytical solutions are used to map the boundary of the irregular refraction region in parameter space. Beyond this boundary, the structure of irregular solutions is investigated via numerical simulations. Particular attention is given to whether all fluid interface emanating from wave intersection points are free of vorticity. This work was partially supported by the KAUST Office of Sponsored Research under Award URF/1/2162-01.

  11. Measurement and Modeling of Personal Exposure to the Electric and Magnetic Fields in the Vicinity of High Voltage Power Lines.

    Science.gov (United States)

    Tourab, Wafa; Babouri, Abdesselam

    2016-06-01

    This work presents an experimental and modeling study of the electromagnetic environment in the vicinity of a high voltage substation located in eastern Algeria (Annaba city) specified with a very high population density. The effects of electromagnetic fields emanating from the coupled multi-lines high voltage power systems (MLHV) on the health of the workers and people living in proximity of substations has been analyzed. Experimental Measurements for the Multi-lines power system proposed have been conducted in the free space under the high voltage lines. Field's intensities were measured using a referenced and calibrated electromagnetic field meter PMM8053B for the levels 0 m, 1 m, 1.5 m and 1.8 m witch present the sensitive's parts as organs and major functions (head, heart, pelvis and feet) of the human body. The measurement results were validated by numerical simulation using the finite element method and these results are compared with the limit values of the international standards. We project to set own national standards for exposure to electromagnetic fields, in order to achieve a regional database that will be at the disposal of partners concerned to ensure safety of people and mainly workers inside high voltage electrical substations.

  12. Engineering field theory

    CERN Document Server

    Baden Fuller, A J

    2014-01-01

    Engineering Field Theory focuses on the applications of field theory in gravitation, electrostatics, magnetism, electric current flow, conductive heat transfer, fluid flow, and seepage.The manuscript first ponders on electric flux, electrical materials, and flux function. Discussions focus on field intensity at the surface of a conductor, force on a charged surface, atomic properties, doublet and uniform field, flux tube and flux line, line charge and line sink, field of a surface charge, field intensity, flux density, permittivity, and Coulomb's law. The text then takes a look at gravitation

  13. Cosmological magnetic fields

    Science.gov (United States)

    Kunze, Kerstin E.

    2013-12-01

    Magnetic fields are observed on nearly all scales in the Universe, from stars and galaxies up to galaxy clusters and even beyond. The origin of cosmic magnetic fields is still an open question, however a large class of models puts its origin in the very early Universe. A magnetic dynamo amplifying an initial seed magnetic field could explain the present day strength of the galactic magnetic field. However, it is still an open problem how and when this initial magnetic field was created. Observations of the cosmic microwave background (CMB) provide a window to the early Universe and might therefore be able to tell us whether cosmic magnetic fields are of a primordial cosmological origin and at the same time constrain its parameters. We will give an overview of the observational evidence of large-scale magnetic fields, describe generation mechanisms of primordial magnetic fields and possible imprints in the CMB.

  14. Terahertz field induced electromigration

    DEFF Research Database (Denmark)

    Strikwerda, Andrew; Zalkovskij, Maksim; Iwaszczuk, Krzysztof

    We report the first observation of THz-field-induced electromigration in sub-wavelength metallic gap structures after exposure to intense single-cycle, sub-picosecond electric field transients of amplitude up to 400 kV/cm....

  15. Magnetic Field Grid Calculator

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Magnetic Field Properties Calculator will computes the estimated values of Earth's magnetic field(declination, inclination, vertical component, northerly...

  16. Beyond the field

    DEFF Research Database (Denmark)

    Lilleør, Helene Bie; Larsen, Anna Folke

    In this paper, we estimate the impact of a farmer field school intervention among small scale farmers in Northers Tanzania. Unlike previous farmer field school evaluations, we go beyond the immediate agricultural impact and estimate the impact of farmer field school participation in the pre-speci...

  17. Dialogue, Field, and Power

    Science.gov (United States)

    Apple, Michael W.

    2017-01-01

    "The Journal of Educational Administration and History" has played an important role as a site for analyses that seek to expand both the academic and the ethical/political concerns of the field. A key word here is field. What counts as the field? What are its boundaries? Who is inside and who is outside? How has that changed over time?…

  18. Politics of aviation fields

    Science.gov (United States)

    Vivent, Jacques

    1922-01-01

    In short, the "politics of aviation" lies in a few propositions: the need of having as large a number of fields as possible and of sufficient area; the utilization of the larger part of the existing military fields; the selection of uncultivated or unproductive fields, whenever technical conditions permit; ability to disregard (save in exceptional cases) objections of an agricultural nature.

  19. Field emission electronics

    CERN Document Server

    Egorov, Nikolay

    2017-01-01

    This book is dedicated to field emission electronics, a promising field at the interface between “classic” vacuum electronics and nanotechnology. In addition to theoretical models, it includes detailed descriptions of experimental and research techniques and production technologies for different types of field emitters based on various construction principles. It particularly focuses on research into and production of field cathodes and electron guns using recently developed nanomaterials and carbon nanotubes. Further, it discusses the applications of field emission cathodes in new technologies such as light sources, flat screens, microwave and X-ray devices.

  20. Classical field theory

    CERN Document Server

    Franklin, Joel

    2017-01-01

    Classical field theory, which concerns the generation and interaction of fields, is a logical precursor to quantum field theory, and can be used to describe phenomena such as gravity and electromagnetism. Written for advanced undergraduates, and appropriate for graduate level classes, this book provides a comprehensive introduction to field theories, with a focus on their relativistic structural elements. Such structural notions enable a deeper understanding of Maxwell's equations, which lie at the heart of electromagnetism, and can also be applied to modern variants such as Chern–Simons and Born–Infeld. The structure of field theories and their physical predictions are illustrated with compelling examples, making this book perfect as a text in a dedicated field theory course, for self-study, or as a reference for those interested in classical field theory, advanced electromagnetism, or general relativity. Demonstrating a modern approach to model building, this text is also ideal for students of theoretic...

  1. Forces in electromagnetic field and gravitational field

    OpenAIRE

    Weng, Zihua

    2008-01-01

    The force can be defined from the linear momentum in the gravitational field and electromagnetic field. But this definition can not cover the gradient of energy. In the paper, the force will be defined from the energy and torque in a new way, which involves the gravitational force, electromagnetic force, inertial force, gradient of energy, and some other new force terms etc. One of these new force terms can be used to explain why the solar wind varies velocity along the magnetic force line in...

  2. Nonlocal continuum field theories

    CERN Document Server

    2002-01-01

    Nonlocal continuum field theories are concerned with material bodies whose behavior at any interior point depends on the state of all other points in the body -- rather than only on an effective field resulting from these points -- in addition to its own state and the state of some calculable external field. Nonlocal field theory extends classical field theory by describing the responses of points within the medium by functionals rather than functions (the "constitutive relations" of classical field theory). Such considerations are already well known in solid-state physics, where the nonlocal interactions between the atoms are prevalent in determining the properties of the material. The tools developed for crystalline materials, however, do not lend themselves to analyzing amorphous materials, or materials in which imperfections are a major part of the structure. Nonlocal continuum theories, by contrast, can describe these materials faithfully at scales down to the lattice parameter. This book presents a unif...

  3. Switchable field-tuned control of magnetic domain wall pinning along Co microwires by 3D e-beam lithographed structures

    Energy Technology Data Exchange (ETDEWEB)

    Blanco-Roldán, C., E-mail: c.blanco@cinn.es [Departamento de Física, Universidad de Oviedo, Avenida Calvo Sotelo s/n, 33007 Oviedo (Spain); Centro de Investigación en Nanomateriales y Nanotecnología CINN (CSIC, Universidad de Oviedo), Avenida de la Vega 4-6, 33940 El Entrego (Spain); Quirós, C.; Rodriguez-Rodriguez, G.; Vélez, M.; Martín, J.I.; Alameda, J.M. [Departamento de Física, Universidad de Oviedo, Avenida Calvo Sotelo s/n, 33007 Oviedo (Spain); Centro de Investigación en Nanomateriales y Nanotecnología CINN (CSIC, Universidad de Oviedo), Avenida de la Vega 4-6, 33940 El Entrego (Spain)

    2016-02-15

    Three-dimensional magnetic circuits composed of Co microwires crossed by elevated Co bridges have been patterned on Si substrate by e-beam lithography and lift-off process. The lithographic procedure includes a double resist procedure that optimizes the shape of the bridge, so that 200 nm air gaps can be routinely achieved in between the wire and bridge elements. Microwire magnetization reversal processes have been analyzed by magneto-optical Kerr effect microscopy with different remanent bridge configurations. When the Co bridge is magnetized along the in-plane direction parallel to the wire axis, its stray field induces a marked pinning effect on domain wall propagation along the wire below it, even without being in contact. Changing the sign of the remanent state of the bridge, domain wall pinning can be selected to occur in either the ascending or descending branches of the wire hysteresis loop. Thus, these wire-bridge 3D circuits provide a simple system for tunable domain wall pinning controllable through the pre-recorded bridge remanent state. - Highlights: • Electron beam lithography is used to fabricate a tridimensional magnetic circuit. • Proposed circuit is made of a Co bridge overcrossing a non-contacted Co microwire. • Domain wall propagation can be controlled by previous magnetization of the system. • Domain wall pinning in the wire depends on the applied magnetic field sign.

  4. Facility Measures Magnetic Fields

    Science.gov (United States)

    Honess, Shawn B.; Narvaez, Pablo; Mcauley, James M.

    1991-01-01

    Partly automated facility measures and computes steady near magnetic field produced by object. Designed to determine magnetic fields of equipment to be installed on spacecraft including sensitive magnetometers, with view toward application of compensating fields to reduce interfernece with spacecraft-magnetometer readings. Because of its convenient operating features and sensitivity of its measurements, facility serves as prototype for similar facilities devoted to magnetic characterization of medical equipment, magnets for high-energy particle accelerators, and magnetic materials.

  5. Organic magnetic field sensor

    Science.gov (United States)

    McCamey, Dane; Boehme, Christoph

    2017-01-24

    An organic, spin-dependent magnetic field sensor (10) includes an active stack (12) having an organic material with a spin-dependence. The sensor (10) also includes a back electrical contact (14) electrically coupled to a back of the active stack (12) and a front electrical contact (16) electrically coupled to a front of the active stack (12). A magnetic field generator (18) is oriented so as to provide an oscillating magnetic field which penetrates the active stack (12).

  6. Algebraic extensions of fields

    CERN Document Server

    McCarthy, Paul J

    1991-01-01

    ""...clear, unsophisticated and direct..."" - MathThis textbook is intended to prepare graduate students for the further study of fields, especially algebraic number theory and class field theory. It presumes some familiarity with topology and a solid background in abstract algebra. Chapter 1 contains the basic results concerning algebraic extensions. In addition to separable and inseparable extensions and normal extensions, there are sections on finite fields, algebraically closed fields, primitive elements, and norms and traces. Chapter 2 is devoted to Galois theory. Besides the fundamenta

  7. Dielectrics in electric fields

    CERN Document Server

    Raju, Gorur G

    2003-01-01

    Discover nontraditional applications of dielectric studies in this exceptionally crafted field reference or text for seniors and graduate students in power engineering tracks. This text contains more than 800 display equations and discusses polarization phenomena in dielectrics, the complex dielectric constant in an alternating electric field, dielectric relaxation and interfacial polarization, the measurement of absorption and desorption currents in time domains, and high field conduction phenomena. Dielectrics in Electric Fields is an interdisciplinary reference and text for professionals and students in electrical and electronics, chemical, biochemical, and environmental engineering; physical, surface, and colloid chemistry; materials science; and chemical physics.

  8. Abandoned Texas oil fields

    Energy Technology Data Exchange (ETDEWEB)

    1980-12-01

    Data for Texas abandoned oil fields were primarily derived from two sources: (1) Texas Railroad Commission (TRRC), and (2) Dwight's ENERGYDATA. For purposes of this report, abandoned oil fields are defined as those fields that had no production during 1977. The TRRC OILMASTER computer tapes were used to identify these abandoned oil fields. The tapes also provided data on formation depth, gravity of oil production, location (both district and county), discovery date, and the cumulative production of the field since its discovery. In all, the computer tapes identified 9211 abandoned fields, most of which had less than 250,000 barrel cumulative production. This report focuses on the 676 abandoned onshore Texas oil fields that had cumulative production of over 250,000 barrels. The Dwight's ENERGYDATA computer tapes provided production histories for approximately two-thirds of the larger fields abandoned in 1966 and thereafter. Fields which ceased production prior to 1966 will show no production history nor abandonment date in this report. The Department of Energy hopes the general availability of these data will catalyze the private sector recovery of this unproduced resource.

  9. Efficient modeling of flat and homogeneous acoustic treatments for vibroacoustic finite element analysis. Direct field formulations

    Science.gov (United States)

    Alimonti, L.; Atalla, N.

    2016-04-01

    This paper is concerned with the development of a simplified model for noise control treatments to speed up finite element analysis in vibroacoustic applications. The methodology relies on the assumption that the acoustic treatment is flat and homogeneous. Moreover, its finite lateral extent is neglected. This hypothesis is justified by short wavelength and large dissipation, which suggest that the reflected field emanating from the acoustic treatment lateral boundaries does not substantially affect its dynamic response. Under these circumstances, the response of the noise control treatment can be formally obtained by means of convolution integrals involving simple analytical kernels (i.e. Green functions). Such fundamental solutions can be computed efficiently by the transfer matrix method. However, some arbitrariness arises in the formulation of the mathematical model, resulting in different baffling conditions at the two ends of the treatment to be considered. Thus, the paper investigates the possibility of different formulations (i.e. baffling conditions) within the same hybrid finite element-transfer matrix framework, seeking for the best strategy in terms of tradeoff between efficiency and accuracy. Numerical examples are provided to show strengths and limitations of the proposed methodology.

  10. Validity of the mean-field approximation for diffusion on a random comb

    Science.gov (United States)

    Revathi, S.; Balakrishnan, V.; Lakshmibala, S.; Murthy, K. P. N.

    1996-09-01

    We consider unbiased diffusion on a random comb structure (an infinitely long backbone with loopless branches of arbitrary length emanating from it). If w=T0 is the mean time (averaged over all random walks) for first passage from an arbitrary origin 0 on the backbone to either of the sites +j or -j on it in a given realization of the structure, the exact diffusion constant for the problem is defined as K=limj-->∞j2c, where c stands for the configuration average over the realizations of the random comb. The diffusion constant in the mean-field approximation is given by KMF=limj-->∞j2/c. We compute T0 exactly for an arbitrary realization of the comb and then show rigorously that, owing to the suppression of the relative fluctuations in T0 in the ``thermodynamic limit'' j-->∞, we have KMF=K whenever the moments of certain random variables Γ(L,α,β) are finite; here the site-dependent random variables L, α, and β are, respectively, the branch length, stay probability at the tip of a branch, and the backbone-to-branch jump probability. Finally, we discuss different situations in which K will not be equal to KMF, although the transport remains diffusive, as opposed to those in which anomalous diffusion occurs.

  11. Local Interstellar Magnetic Field Determined from the Interstellar Boundary Explorer Ribbon

    Science.gov (United States)

    Zirnstein, E. J.; Heerikhuisen, J.; Funsten, H. O.; Livadiotis, G.; McComas, D. J.; Pogorelov, N. V.

    2016-02-01

    The solar wind emanating from the Sun interacts with the local interstellar medium (LISM), forming the heliosphere. Hydrogen energetic neutral atoms (ENAs) produced by the solar-interstellar interaction carry important information about plasma properties from the boundaries of the heliosphere, and are currently being measured by NASA's Interstellar Boundary Explorer (IBEX). IBEX observations show the existence of a “ribbon” of intense ENA emission projecting a circle on the celestial sphere that is centered near the local interstellar magnetic field (ISMF) vector. Here we show that the source of the IBEX ribbon as a function of ENA energy outside the heliosphere, uniquely coupled to the draping of the ISMF around the heliopause, can be used to precisely determine the magnitude (2.93 ± 0.08 μG) and direction (227.°28 ± 0.°69, 34.°62 ± 0.°45 in ecliptic longitude and latitude) of the pristine ISMF far (∼1000 AU) from the Sun. We find that the ISMF vector is offset from the ribbon center by ∼8.°3 toward the direction of motion of the heliosphere through the LISM, and their vectors form a plane that is consistent with the direction of deflected interstellar neutral hydrogen, thought to be controlled by the ISMF. Our results yield draped ISMF properties close to that observed by Voyager 1, the only spacecraft to directly measure the ISMF close to the heliosphere, and give predictions of the pristine ISMF that Voyager 1 has yet to sample.

  12. Atomic-scale sensing of the magnetic dipolar field from single atoms

    Science.gov (United States)

    Choi, Taeyoung; Paul, William; Rolf-Pissarczyk, Steffen; MacDonald, Andrew J.; Natterer, Fabian D.; Yang, Kai; Willke, Philip; Lutz, Christopher P.; Heinrich, Andreas J.

    2017-05-01

    Spin resonance provides the high-energy resolution needed to determine biological and material structures by sensing weak magnetic interactions. In recent years, there have been notable achievements in detecting and coherently controlling individual atomic-scale spin centres for sensitive local magnetometry. However, positioning the spin sensor and characterizing spin-spin interactions with sub-nanometre precision have remained outstanding challenges. Here, we use individual Fe atoms as an electron spin resonance (ESR) sensor in a scanning tunnelling microscope to measure the magnetic field emanating from nearby spins with atomic-scale precision. On artificially built assemblies of magnetic atoms (Fe and Co) on a magnesium oxide surface, we measure that the interaction energy between the ESR sensor and an adatom shows an inverse-cube distance dependence (r-3.01±0.04). This demonstrates that the atoms are predominantly coupled by the magnetic dipole-dipole interaction, which, according to our observations, dominates for atom separations greater than 1 nm. This dipolar sensor can determine the magnetic moments of individual adatoms with high accuracy. The achieved atomic-scale spatial resolution in remote sensing of spins may ultimately allow the structural imaging of individual magnetic molecules, nanostructures and spin-labelled biomolecules.

  13. Fielding a current idea: exploring the public health impact of electromagnetic radiation.

    Science.gov (United States)

    Genuis, Stephen J

    2008-02-01

    Several publications in the scientific literature have raised concern about the individual and public health impact of adverse non-ionizing radiation (a-NIR) from electromagnetic field (EMF) exposure emanating from certain power, electrical and wireless devices commonly found in the home, workplace, school and community. Despite the many challenges in establishing irrefutable scientific proof of harm and the various gaps in elucidating the precise mechanisms of harm, epidemiological analyses continue to suggest considerable potential for injury and affliction as a result of a-NIR exposure. As environmental health has not been emphasized in medical education, some clinicians are not fully aware of possible EMF-related health problems and, as a result, manifestations of a-NIR may remain misdiagnosed and ineffectually managed. It is important for physicians and public health officials to be aware of the fundamental science and clinical implications of EMF exposure. A review of the scientific literature relating to the link between electromagnetic radiation and human health, several public health recommendations, and four case histories are presented for consideration.

  14. Small field dose delivery evaluations using cone beam optical computed tomography-based polymer gel dosimetry

    Directory of Open Access Journals (Sweden)

    Timothy Olding

    2011-01-01

    Full Text Available This paper explores the combination of cone beam optical computed tomography with an N-isopropylacrylamide (NIPAM-based polymer gel dosimeter for three-dimensional dose imaging of small field deliveries. Initial investigations indicate that cone beam optical imaging of polymer gels is complicated by scattered stray light perturbation. This can lead to significant dosimetry failures in comparison to dose readout by magnetic resonance imaging (MRI. For example, only 60% of the voxels from an optical CT dose readout of a 1 l dosimeter passed a two-dimensional Low′s gamma test (at a 3%, 3 mm criteria, relative to a treatment plan for a well-characterized pencil beam delivery. When the same dosimeter was probed by MRI, a 93% pass rate was observed. The optical dose measurement was improved after modifications to the dosimeter preparation, matching its performance with the imaging capabilities of the scanner. With the new dosimeter preparation, 99.7% of the optical CT voxels passed a Low′s gamma test at the 3%, 3 mm criteria and 92.7% at a 2%, 2 mm criteria. The fitted interjar dose responses of a small sample set of modified dosimeters prepared (a from the same gel batch and (b from different gel batches prepared on the same day were found to be in agreement to within 3.6% and 3.8%, respectively, over the full dose range. Without drawing any statistical conclusions, this experiment gives a preliminary indication that intrabatch or interbatch NIPAM dosimeters prepared on the same day should be suitable for dose sensitivity calibration.

  15. Electromagnetic fields in biological systems

    National Research Council Canada - National Science Library

    Lin, James C

    2012-01-01

    "Focusing on exposure, induced fields, and absorbed energy, this volume covers the interaction of electromagnetic fields and waves with biological systems, spanning static fields to terahertz waves...

  16. Covariant lattice glueball fields

    Science.gov (United States)

    Mandula, Jeffrey E.; Zweig, George; Govaerts, Jan

    1983-11-01

    Fields for the creation and annihilation of gluons and glueballs, which transform irreducibly under the four-dimensional lattice rotation reflection and charge conjugation symmetry groups, are defined and discussed. The fields reduce in the zero lattice spacing limit to conventional continuum operators of definite spin, parity, and charge comjugation.

  17. Covariant lattice glueball fields

    Energy Technology Data Exchange (ETDEWEB)

    Mandula, J.E.; Zweig, G.; Govaerts, J.

    1983-11-15

    Fields for the creation and annihilation of gluons and glueballs, which transform irreducibly under the four-dimensional lattice rotation reflection and charge conjugation symmetry groups, are defined and discussed. The fields reduce in the zero lattice spacing limit to conventional continuum operators of definite spin, parity, and charge conjugation.

  18. Cosmological magnetic fields - V

    Indian Academy of Sciences (India)

    The field tensor is observer-independent, while the electric and magnetic ... Thus the electric field in the particle frame vanishes: Щ = 0. In the observer's frame, with four velocity. Щ = Щ + Ъ , where Ъ is the relative velocity (Ъ Щ = 0) and we neglect ... The key equation is (8), which is the induction equation in covariant form.

  19. Progress in field spectroscopy

    NARCIS (Netherlands)

    Milton, E.J.; Schaepman, M.E.; Anderson, K.; Kneubühler, M.; Fox, N.

    2009-01-01

    This paper reviews developments in the science of field spectroscopy, focusing on the last twenty years in particular. During this period field spectroscopy has become established as an important technique for characterising the reflectance of natural surfaces in situ, for supporting the vicarious

  20. Voices from the Field

    Science.gov (United States)

    Keilty, Bonnie

    2013-01-01

    Early intervention takes its form from a variety of fields. It has its obvious roots in the fields that primarily provide early intervention services--special education, allied health, and early childhood education. Early intervention also draws from public health as a coordinated approach to addressing the biological, psychological, and social…

  1. Mean field games

    KAUST Repository

    Gomes, Diogo A.

    2014-01-06

    In this talk we will report on new results concerning the existence of smooth solutions for time dependent mean-field games. This new result is established through a combination of various tools including several a-priori estimates for time-dependent mean-field games combined with new techniques for the regularity of Hamilton-Jacobi equations.

  2. twistors and gauge fields

    Directory of Open Access Journals (Sweden)

    A. G. Sergeev

    1986-01-01

    Full Text Available We describe briefly the basic ideas and results of the twistor theory. The main points: twistor representation of Minkowsky space, Penrose correspondence and its geometrical properties, twistor interpretation of linear massless fields, Yang-Mills fields (including instantons and monopoles and Einstein-Hilbert equations.

  3. Pulsed electric fields

    Science.gov (United States)

    The concept of pulsed electric fields (PEF) was first proposed in 1967 to change the behavior or microorganisms. The electric field phenomenon was identified as membrane rupture theory in the 1980s. Increasing the membrane permeability led to the application of PEF assisted extraction of cellular co...

  4. Electric field analysis

    CERN Document Server

    Chakravorti, Sivaji

    2015-01-01

    This book prepares newcomers to dive into the realm of electric field analysis. The book details why one should perform electric field analysis and what are its practical implications. It emphasizes both the fundamentals and modern computational methods of electric machines. The book covers practical applications of the numerical methods in high voltage equipment, including transmission lines, power transformers, cables, and gas insulated systems.

  5. Diagnostics and field experiments

    NARCIS (Netherlands)

    Voors, Maarten

    2018-01-01

    Field experiments have been embraced in development economics and political science as a core method to learn what development interventions work and why. Scientists across the globe actively engage with development practitioners to evaluate projects and programmes. However, even though field

  6. Quantum Field Theory

    OpenAIRE

    Wilczek, Frank

    1998-01-01

    I discuss the general principles underlying quantum field theory, and attempt to identify its most profound consequences. The deepest of these consequences result from the infinite number of degrees of freedom invoked to implement locality. I mention a few of its most striking successes, both achieved and prospective. Possible limitations of quantum field theory are viewed in the light of its history.

  7. Ridge and Furrow Fields

    DEFF Research Database (Denmark)

    Møller, Per Grau

    2016-01-01

    Ridge and furrow is a specific way of ploughing which makes fields of systematic ridges and furrows like a rubbing washboard. They are part of an overall openfield system, but the focus in this paper is on the functionality of the fields. There are many indications that agro-technological reasons...

  8. Electromagnetic Fields and Cancer

    Science.gov (United States)

    ... to magnetic fields and acute lymphoblastic leukemia in children. New England Journal of Medicine 1997; 337(1):1-7. [PubMed ... Magnetic field exposure and long-term survival among children with leukaemia. British Journal of Cancer 2006; 94(1):161-164. [PubMed ...

  9. Moving Field Guides

    Science.gov (United States)

    Cassie Meador; Mark Twery; Meagan. Leatherbury

    2011-01-01

    The Moving Field Guides (MFG) project is a creative take on site interpretation. Moving Field Guides provide an example of how scientific and artistic endeavors work in parallel. Both begin with keen observations that produce information that must be analyzed, understood, and interpreted. That interpretation then needs to be communicated to others to complete the...

  10. Prevalência de Echinococcus granulosus (Batsch, 1786 em cães urbanos errantes do município de Dom Pedrito (RS, Brasil Prevalence of Echinococcus granulosus (Batsch, 1786 in urban stray dogs from Dom Pedrito in the State of Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Adriane Nunes Hoffmann

    2001-10-01

    Full Text Available Echinococcus granulosus é um dos parasitas mais importantes envolvidos em zoonoses de municípios próximos a fronteira do Rio grande do Sul com a Argentina e Uruguai. Amostras de 65 cães urbanos errantes do município de Dom Pedrito foram analisadas por meio de três técnicas: purgação pelo bromidrato de arecolina para visualização da presença do parasito; ensaio de imunoadsorção enzimática (ELISA, para detecção de coproantígenos, imunofluorescência indireta (IFI, para detecção de anticorpos séricos contra E. granulosus. Destes cães, 7,7% (5/65 apresentaram o parasita nas fezes, 10,8 (7/65 coproantígenos e 13,8% (9/65 anticorpos séricos contra o cestódeo. Conclui-se que a equinococose canina, no meio urbano, pode representar um sério problema à saúde pública, devido ao risco de hidatidose humana.Echinococcus granulosus is the one of the most important parasites involved in zoonosis in the State of Rio Grande do Sul, in cities near the Argentinian and Uruguayian border. Sixty-five samples of urban stray dogs from Dom Pedrito county were analyzed by three techniques: purgation by arecoline hydrobromide, to verify the presence of the parasite; enzyme-linked immunosorbent assay test (ELISA, to detect the coproantigen and indirect immunofluorescence antibody test (IFA to identify serum antibodies against E. granulosus. From the analyzed dogs 7.7% (5/65 have presented the parasite in feces, 10.8% (7/65 had coproantigens and 13.8% (9/65 serum antibodies against this cestode. It was concluded that canine echinococcosis in the urban zone may represent a serious problem to public health, due to hidatidosis risk for humans.

  11. Compressive light field displays.

    Science.gov (United States)

    Wetzstein, Gordon; Lanman, Douglas; Hirsch, Matthew; Heidrich, Wolfgang; Raskar, Ramesh

    2012-01-01

    Light fields are the multiview extension of stereo image pairs: a collection of images showing a 3D scene from slightly different perspectives. Depicting high-resolution light fields usually requires an excessively large display bandwidth; compressive light field displays are enabled by the codesign of optical elements and computational-processing algorithms. Rather than pursuing a direct "optical" solution (for example, adding one more pixel to support the emission of one additional light ray), compressive displays aim to create flexible optical systems that can synthesize a compressed target light field. In effect, each pixel emits a superposition of light rays. Through compression and tailored optical designs, fewer display pixels are necessary to emit a given light field than a direct optical solution would require.

  12. Dual double field theory

    Energy Technology Data Exchange (ETDEWEB)

    Bergshoeff, Eric A. [Centre for Theoretical Physics, University of Groningen,Nijenborgh 4, 9747 AG Groningen (Netherlands); Hohm, Olaf [Simons Center for Geometry and Physics, Stony Brook University,Stony Brook, NY 11794-3636 (United States); Penas, Victor A. [Centre for Theoretical Physics, University of Groningen,Nijenborgh 4, 9747 AG Groningen (Netherlands); Riccioni, Fabio [INFN - Sezione di Roma, Dipartimento di Fisica, Università di Roma “La Sapienza”,Piazzale Aldo Moro 2, 00185 Roma (Italy)

    2016-06-06

    We present the dual formulation of double field theory at the linearized level. This is a classically equivalent theory describing the duals of the dilaton, the Kalb-Ramond field and the graviton in a T-duality or O(D,D) covariant way. In agreement with previous proposals, the resulting theory encodes fields in mixed Young-tableau representations, combining them into an antisymmetric 4-tensor under O(D,D). In contrast to previous proposals, the theory also requires an antisymmetric 2-tensor and a singlet, which are not all pure gauge. The need for these additional fields is analogous to a similar phenomenon for “exotic' dualizations, and we clarify this by comparing with the dualizations of the component fields. We close with some speculative remarks on the significance of these observations for the full non-linear theory yet to be constructed.

  13. The Coriolis field

    CERN Document Server

    Costa, L Filipe

    2015-01-01

    We present a pedagogical discussion of the Coriolis field, emphasizing its not-so-well-understood aspects. We show that this field satisfies the field equations of the so-called Newton-Cartan theory, a generalization of Newtonian gravity that is covariant under changes of arbitrarily rotating and accelerated frames. Examples of solutions of this theory are given, including the Newtonian analogue of the G\\"odel universe. We discuss how to detect the Coriolis field by its effect on gyroscopes, of which the gyrocompass is an example. Finally, using a similar framework, we discuss the Coriolis field generated by mass currents in general relativity, and its measurement by the Gravity Probe B and LAGEOS/LARES experiments.

  14. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    Dias, Kealey

    The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...... or meromorphic (allowing poles as singularities) functions. There already exists a well-developed theory for iterative holomorphic dynamical systems, and successful relations found between iteration theory and flows of vector fields have been one of the main motivations for the recent interest in holomorphic...... vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...

  15. Quantum theory of fields

    CERN Document Server

    Wentzel, Gregor

    2003-01-01

    A prominent figure in twentieth-century physics, Gregor Wentzel made major contributions to the development of quantum field theory, first in Europe and later at the University of Chicago. His Quantum Theory of Fields offers a knowledgeable view of the original literature of elementary quantum mechanics and helps make these works accessible to interested readers.An introductory volume rather than an all-inclusive account, the text opens with an examination of general principles, without specification of the field equations of the Lagrange function. The following chapters deal with particular

  16. Industasis, a promotion of tumor formation by nontumorigenic stray cells

    Czech Academy of Sciences Publication Activity Database

    Pajer, Petr; Karafiát, Vít; Pečenka, Vladimír; Průková, Dana; Dudlová, J.; Plachý, Jiří; Kašparová, P.; Dvořák, Michal

    2009-01-01

    Roč. 69, č. 11 (2009), s. 4605-4612 ISSN 0008-5472 R&D Projects: GA ČR GA204/06/1728; GA MŠk(CZ) LC06061; GA AV ČR IAA500520608 Institutional research plan: CEZ:AV0Z50520514 Keywords : tumor promotion * lung tumors * Fyn-related kinase Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 7.543, year: 2009

  17. Cell reintegration: Stray epithelial cells make their way home.

    Science.gov (United States)

    Wilson, Tyler J; Bergstralh, Dan T

    2017-06-01

    Ongoing work shows that misplaced epithelial cells have the capacity to reintegrate back into tissue layers. This movement appears to underlie tissue stability and may also control aspects of tissue structure. A recent study reveals that cell reintegration in at least one tissue, the Drosophila follicular epithelium, is based on adhesion molecules that line lateral cell surfaces. In this article we will review these observations, discuss their implications for epithelial tissue development and maintenance, and identify future directions for study. © 2017 WILEY Periodicals, Inc.

  18. Stray dog meat consumption and rabies | Wiwanitkit | African Health ...

    African Journals Online (AJOL)

    African Health Sciences. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 14, No 3 (2014) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your Web ...

  19. Field Geology/Processes

    Science.gov (United States)

    Allen, Carlton; Jakes, Petr; Jaumann, Ralf; Marshall, John; Moses, Stewart; Ryder, Graham; Saunders, Stephen; Singer, Robert

    1996-01-01

    The field geology/process group examined the basic operations of a terrestrial field geologist and the manner in which these operations could be transferred to a planetary lander. Four basic requirements for robotic field geology were determined: geologic content; surface vision; mobility; and manipulation. Geologic content requires a combination of orbital and descent imaging. Surface vision requirements include range, resolution, stereo, and multispectral imaging. The minimum mobility for useful field geology depends on the scale of orbital imagery. Manipulation requirements include exposing unweathered surfaces, screening samples, and bringing samples in contact with analytical instruments. To support these requirements, several advanced capabilities for future development are recommended. Capabilities include near-infrared reflectance spectroscopy, hyper-spectral imaging, multispectral microscopy, artificial intelligence in support of imaging, x ray diffraction, x ray fluorescence, and rock chipping.

  20. Crystal Field Handbook

    Science.gov (United States)

    Newman, D. J.; Ng, Betty

    2007-09-01

    List of contributors; Preface; Introduction; 1. Crystal field splitting mechanisms D. J. Newman and Betty Ng; 2. Empirical crystal fields D. J. Newman and Betty Ng; 3. Fitting crystal field parameters D. J. Newman and Betty Ng; 4. Lanthanide and actinide optical spectra G. K. Liu; 5. Superposition model D. J. Newman and Betty Ng; 6. Effects of electron correlation on crystal field splitting M. F. Reid and D. J. Newman; 7. Ground state splittings in S-state ions D. J. Newman and Betty Ng; 8. Invariants and moments Y. Y. Yeung; 9. Semiclassical model K. S. Chan; 10. Transition intensities M. F. Reid; Appendix 1. Point symmetry D. J. Newman and Betty Ng; Appendix 2. QBASIC programs D. J. Newman and Betty Ng; Appendix 3. Accessible program packages Y. Y. Yeung, M. F. Reid and D. J. Newman; Appendix 4. Computer package CST Cz. Rudowicz; Bibliography; Index.

  1. Electric & Magnetic Fields

    Science.gov (United States)

    ... Reading Introduction Electric and magnetic fields (EMFs) are invisible areas of energy, often referred to as radiation , ... Abstract ] Staff Directory Freedom of Information Act OIG Web Policies Request Translation Services Employment Verification Contact Us ...

  2. Field Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Field Research Facility (FRF) located in Duck, N.C. was established in 1977 to support the U.S. Army Corps of Engineers' coastal engineering mission. The FRF is...

  3. Maine Field Station

    Data.gov (United States)

    Federal Laboratory Consortium — In 2000 NOAA's National Marine Fisheries Service established the Maine Field Station in Orono, ME to have more direct involvement in the conservation of the living...

  4. Gauge fields in graphene

    National Research Council Canada - National Science Library

    Vozmediano, M.A.H; Katsnelson, M.I; Guinea, F

    2010-01-01

    The physics of graphene is acting as a bridge between quantum field theory and condensed matter physics due to the special quality of the graphene quasiparticles behaving as massless two dimensional Dirac fermions...

  5. Microreactors with electrical fields

    NARCIS (Netherlands)

    Agiral, A.; Gardeniers, Johannes G.E.

    2010-01-01

    The use of electric fields in chemistry is considered an important concept of process intensification. The combination of electricity with chemistry becomes particularly valuable at smaller scales, as they are exploited in microreaction technology. Microreactor systems with integrated electrodes

  6. Cosmic magnetic fields

    CERN Document Server

    Sánchez Almeida, Jorge

    2018-01-01

    Magnetic fields pervade the universe and play an important role in many astrophysical processes. However, they require specialised observational tools, and are challenging to model and understand. This volume provides a unified view of magnetic fields across astrophysical and cosmological contexts, drawing together disparate topics that are rarely covered together. Written by the lecturers of the XXV Canary Islands Winter School, it offers a self-contained introduction to cosmic magnetic fields on a range of scales. The connections between the behaviours of magnetic fields in these varying contexts are particularly emphasised, from the relatively small and close ranges of the Sun, planets and stars, to galaxies and clusters of galaxies, as well as on cosmological scales. Aimed at young researchers and graduate students, this up-to-date review uniquely brings together a subject often tackled by disconnected communities, conveying the latest advances as well as highlighting the limits of our current understandi...

  7. Introduction to Geomagnetic Fields

    Science.gov (United States)

    Hinze, William J.

    Coincidentally, as I sat down in late October 2003 to read and review the second edition of Wallace H. Campbell's text, Introduction to Geomagnetic Fields, we received warnings from the news media of a massive solar flare and its possible effect on power supply systems and satellite communications. News programs briefly explained the source of Sun-Earth interactions. If you are interested in learning more about the physics of the connection between sun spots and power supply systems and their impact on orbiting satellites, I urge you to become acquainted with Campbell's book. It presents an interesting and informative explanation of the geomagnetic field and its applications to a wide variety of topics, including oil exploration, climate change, and fraudulent claims of the utility of magnetic fields for alleviating human pain. Geomagnetism, the study of the nature and processes of the Earth's magnetic fields and its application to the investigation of the Earth, its processes, and history, is a mature science with a well-developed theoretical foundation and a vast array of observations. It is discussed in varied detail in Earth physics books and most entry-level geoscience texts. The latter treatments largely are driven by the need to discuss paleomagnetism as an essential tool in studying plate tectonics. A more thorough explanation of geomagnetism is needed by many interested scientists in related fields and by laypersons. This is the objective of Campbell's book. It is particularly germane in view of a broad range of geomagnetic topics that are at the forefront of today's science, including environmental magnetism, so-called ``jerks'' observed in the Earth's magnetic field, the perplexing magnetic field of Mars, improved satellite magnetic field observations, and the increasing availability of high-quality continental magnetic anomaly maps, to name only a few.

  8. DSM-5 field survey

    DEFF Research Database (Denmark)

    Lochner, Christine; Grant, Jon E; Odlaug, Brian Lawrence

    2012-01-01

    The aim of this multisite field survey was to examine the DSM-IV-TR criteria, proposed DSM-5 diagnostic criteria, as well as a number of possible additional diagnostic criteria, in patients with hair-pulling disorder (HPD, or trichotillomania).......The aim of this multisite field survey was to examine the DSM-IV-TR criteria, proposed DSM-5 diagnostic criteria, as well as a number of possible additional diagnostic criteria, in patients with hair-pulling disorder (HPD, or trichotillomania)....

  9. Ordered Rings and Fields

    Directory of Open Access Journals (Sweden)

    Schwarzweller Christoph

    2017-03-01

    Full Text Available We introduce ordered rings and fields following Artin-Schreier’s approach using positive cones. We show that such orderings coincide with total order relations and give examples of ordered (and non ordered rings and fields. In particular we show that polynomial rings can be ordered in (at least two different ways [8, 5, 4, 9]. This is the continuation of the development of algebraic hierarchy in Mizar [2, 3].

  10. a field study

    OpenAIRE

    Köster, Gudrun

    2010-01-01

    Factors influencing udder health and prevalence of mastitis pathogens and their resistance to antimicrobials in large dairy herds in Brandenburg, Germany- a field study The objective of the field study was to 1) investigate factors influencing udder health in dairy herds in Brandenburg, Germany and 2) to describe prevalence and spreading of mastitis pathogens and their resistance patterns to antimicrobials. Eighty dairy farms were visited between July 2001 and October 2002. Data were evalu...

  11. Condensed Matter Field Theory

    Science.gov (United States)

    Altland, Alexander; Simons, Ben

    2006-06-01

    Over the past few decades, in concert with ground-breaking experimental advances, condensed matter theory has drawn increasingly from the language of low-energy quantum field theory. This primer is aimed at elevating graduate students of condensed matter theory to a level where they can engage in independent research. It emphasizes the development of modern methods of classical and quantum field theory with applications oriented around condensed matter physics. Topics covered include second quantization, path and functional field integration, mean-field theory and collective phenomena, the renormalization group, and topology. Conceptual aspects and formal methodology are emphasized, but the discussion is rooted firmly in practical experimental application. As well as routine exercises, the text includes extended and challenging problems, with fully worked solutions, designed to provide a bridge between formal manipulations and research-oriented thinking. This book will complement graduate level courses on theoretical quantum condensed matter physics. Spans the field of modern condensed matter theory focusing on field theory techniques Written to facilitate learning, with numerous challenging exercises, with fully worked solutions, aimed at physicists starting graduate-level courses The theoretical methods are firmly set in concrete experimental applications

  12. Application of an Optimal Search Strategy for the DNAPL Source Identification to a Field Site in Nanjing, China

    Science.gov (United States)

    Longting, M.; Ye, S.; Wu, J.

    2014-12-01

    Identification and removing the DNAPL source in aquifer system is vital in rendering remediation successful and lowering the remediation time and cost. Our work is to apply an optimal search strategy introduced by Zoi and Pinder[1], with some modifications, to a field site in Nanjing City, China to define the strength, and location of DNAPL sources using the least samples. The overall strategy uses Monte Carlo stochastic groundwater flow and transport modeling, incorporates existing sampling data into the search strategy, and determines optimal sampling locations that are selected according to the reduction in overall uncertainty of the field and the proximity to the source locations. After a sample is taken, the plume is updated using a Kalman filter. The updated plume is then compared to the concentration fields that emanate from each individual potential source using fuzzy set technique. The comparison followed provides weights that reflect the degree of truth regarding the location of the source. The above steps are repeated until the optimal source characteristics are determined. Considering our site case, some specific modifications and work have been done as follows. K random fields are generated after fitting the measurement K data to the variogram model. The locations of potential sources that are given initial weights are targeted based on the field survey, with multiple potential source locations around the workshops and wastewater basin. Considering the short history (1999-2010) of manufacturing optical brightener PF at the site, and the existing sampling data, a preliminary source strength is then estimated, which will be optimized by simplex method or GA later. The whole algorithm then will guide us for optimal sampling and update as the investigation proceeds, until the weights finally stabilized. Reference [1] Dokou Zoi, and George F. Pinder. "Optimal search strategy for the definition of a DNAPL source." Journal of Hydrology 376.3 (2009): 542

  13. A epistemologia transdisciplinar nos pressupostos da Teoria da Complexidade e no contexto da organização do trabalho. (The transdisciplinary epistemology in the theory of complexity of complexity and in the contexto of work organization Doi: 10.5212/Eman

    Directory of Open Access Journals (Sweden)

    Osmar Ponchirolli

    2015-03-01

    interlacing, therefore, what is interlaced together, it consists of a closely woven together fabric, although the wires that constitute are extremely diverse. From the work of Edgar Morin’s “The Method”, this study focuses primarily on the development of the defining features of transdisciplinarity, then the assumptions of complexity theory to organizations can engage with the work then only check how complexity theory and the area of education, which characterizes itself as a company, because the training is grounded theoretically in the educational environment. Complex thinking aims to overcome the closed entities or the disciplines, as a necessary means to conceive the fundamental. Either directly in the area of education, in the construction of complex thinking or in organizations as a field of knowledge, the complexity is available to communicate with all other theories of knowledge, considering the transdisciplinary method as a guide for this approach. The thread of the observation of the assumptions of epistemology proposed by the complexity considers that the one who researches is, before of anything, a researcher of himself, so the life of Edgar Morin, founder of the theory of complexity, is the main constituent of the final considerations of this study. Keywords: Transdisciplinarity. Complexity. Education. Organization. Method.

  14. Nonlinear field space cosmology

    Science.gov (United States)

    Mielczarek, Jakub; Trześniewski, Tomasz

    2017-08-01

    We consider the FRW cosmological model in which the matter content of the Universe (playing the role of an inflaton or quintessence) is given by a novel generalization of the massive scalar field. The latter is a scalar version of the recently introduced nonlinear field space theory, where the physical phase space of a given field is assumed to be compactified at large energies. For our analysis, we choose the simple case of a field with the spherical phase space and endow it with the generalized Hamiltonian analogous to the XXZ Heisenberg model, normally describing a system of spins in condensed matter physics. Subsequently, we study both the homogenous cosmological sector and linear perturbations of such a test field. In the homogenous sector, we find that nonlinearity of the field phase space is becoming relevant for large volumes of the Universe and can lead to a recollapse, and possibly also at very high energies, leading to the phase of a bounce. Quantization of the field is performed in the limit where the nontrivial nature of its phase space can be neglected, while there is a nonvanishing contribution from the Lorentz symmetry breaking term of the Hamiltonian. As a result, in the leading order of the XXZ anisotropy parameter, we find that the inflationary spectral index remains unmodified with respect to the standard case but the total amplitude of perturbations is subject to a correction. The Bunch-Davies vacuum state also becomes appropriately corrected. The proposed new approach is bringing cosmology and condensed matter physics closer together, which may turn out to be beneficial for both disciplines.

  15. Coronal Magnetic Field Models

    Science.gov (United States)

    Wiegelmann, Thomas; Petrie, Gordon J. D.; Riley, Pete

    2017-09-01

    Coronal magnetic field models use photospheric field measurements as boundary condition to model the solar corona. We review in this paper the most common model assumptions, starting from MHD-models, magnetohydrostatics, force-free and finally potential field models. Each model in this list is somewhat less complex than the previous one and makes more restrictive assumptions by neglecting physical effects. The magnetohydrostatic approach neglects time-dependent phenomena and plasma flows, the force-free approach neglects additionally the gradient of the plasma pressure and the gravity force. This leads to the assumption of a vanishing Lorentz force and electric currents are parallel (or anti-parallel) to the magnetic field lines. Finally, the potential field approach neglects also these currents. We outline the main assumptions, benefits and limitations of these models both from a theoretical (how realistic are the models?) and a practical viewpoint (which computer resources to we need?). Finally we address the important problem of noisy and inconsistent photospheric boundary conditions and the possibility of using chromospheric and coronal observations to improve the models.

  16. Multi-valued fields

    CERN Document Server

    Ershov, Yuri L

    2001-01-01

    For more than 30 years, the author has studied the model-theoretic aspects of the theory of valued fields and multi-valued fields. Many of the key results included in this book were obtained by the author whilst preparing the manuscript. Thus the unique overview of the theory, as developed in the book, has been previously unavailable. The book deals with the theory of valued fields and mutli-valued fields. The theory of Prüfer rings is discussed from the `geometric' point of view. The author shows that by introducing the Zariski topology on families of valuation rings, it is possible to distinguish two important subfamilies of Prüfer rings that correspond to Boolean and near Boolean families of valuation rings. Also, algebraic and model-theoretic properties of multi-valued fields with near Boolean families of valuation rings satisfying the local-global principle are studied. It is important that this principle is elementary, i.e., it can be expressed in the language of predicate calculus. The most important...

  17. Field error lottery

    Science.gov (United States)

    James Elliott, C.; McVey, Brian D.; Quimby, David C.

    1991-07-01

    The level of field errors in a free electron laser (FEL) is an important determinant of its performance. We have computed 3D performance of a large laser subsystem subjected to field errors of various types. These calculations have been guided by simple models such as SWOOP. The technique of choice is use of the FELEX free electron laser code that now possesses extensive engineering capabilities. Modeling includes the ability to establish tolerances of various types: fast and slow scale field bowing, field error level, beam position monitor error level, gap errors, defocusing errors, energy slew, displacement and pointing errors. Many effects of these errors on relative gain and relative power extraction are displayed and are the essential elements of determining an error budget. The random errors also depend on the particular random number seed used in the calculation. The simultaneous display of the performance versus error level of cases with multiple seeds illustrates the variations attributable to stochasticity of this model. All these errors are evaluated numerically for comprehensive engineering of the system. In particular, gap errors are found to place requirements beyond convenient mechanical tolerances of ± 25 μm, and amelioration of these may occur by a procedure using direct measurement of the magnetic fields at assembly time.

  18. Switchable field-tuned control of magnetic domain wall pinning along Co microwires by 3D e-beam lithographed structures

    Science.gov (United States)

    Blanco-Roldán, C.; Quirós, C.; Rodriguez-Rodriguez, G.; Vélez, M.; Martín, J. I.; Alameda, J. M.

    2016-02-01

    Three-dimensional magnetic circuits composed of Co microwires crossed by elevated Co bridges have been patterned on Si substrate by e-beam lithography and lift-off process. The lithographic procedure includes a double resist procedure that optimizes the shape of the bridge, so that 200 nm air gaps can be routinely achieved in between the wire and bridge elements. Microwire magnetization reversal processes have been analyzed by magneto-optical Kerr effect microscopy with different remanent bridge configurations. When the Co bridge is magnetized along the in-plane direction parallel to the wire axis, its stray field induces a marked pinning effect on domain wall propagation along the wire below it, even without being in contact. Changing the sign of the remanent state of the bridge, domain wall pinning can be selected to occur in either the ascending or descending branches of the wire hysteresis loop. Thus, these wire-bridge 3D circuits provide a simple system for tunable domain wall pinning controllable through the pre-recorded bridge remanent state.

  19. Electromagnetic fields and life

    CERN Document Server

    Presman, A S

    1970-01-01

    A broad region of the electromagnetic spectrum long assumed to have no influence on living systems under natural conditions has been critically re-examined over the past decade. This spectral region extends from the superhigh radio frequencies, through de­ creasing frequencies, to and including essentially static electric and magnetic fields. The author of this monograph, A. S. Presman, has reviewed not only the extensive Russian literatur!;"l, but also al­l most equally comprehensively the non-Russian literature, dealing with biological influences of these fields. Treated also is literature shedding some light on possible theoretical foundations for these phenomena. A substantial, rapidly increasing number of studies in many laboratories and countries has now clearly established bio­ logical influences which are independent of the theoretically predictable, simple thermal effects. Indeed many of the effects are produced by field strengths very close to those within the natural environment. The author has,...

  20. Cosmic magnetic fields

    CERN Document Server

    Kronberg, Philipp P

    2016-01-01

    Magnetic fields are important in the Universe and their effects contain the key to many astrophysical phenomena that are otherwise impossible to understand. This book presents an up-to-date overview of this fast-growing topic and its interconnections to plasma processes, astroparticle physics, high energy astrophysics, and cosmic evolution. The phenomenology and impact of magnetic fields are described in diverse astrophysical contexts within the Universe, from galaxies to the filaments and voids of the intergalactic medium, and out to the largest redshifts. The presentation of mathematical formulae is accessible and is designed to add insight into the broad range of topics discussed. Written for graduate students and researchers in astrophysics and related disciplines, this volume will inspire readers to devise new ways of thinking about magnetic fields in space on galaxy scales and beyond.

  1. Field Independent Cosmic Evolution

    Directory of Open Access Journals (Sweden)

    Nayem Sk

    2013-01-01

    Full Text Available It has been shown earlier that Noether symmetry does not admit a form of corresponding to an action in which is coupled to scalar-tensor theory of gravity or even for pure theory of gravity taking anisotropic model into account. Here, we prove that theory of gravity does not admit Noether symmetry even if it is coupled to tachyonic field and considering a gauge in addition. To handle such a theory, a general conserved current has been constructed under a condition which decouples higher-order curvature part from the field part. This condition, in principle, solves for the scale-factor independently. Thus, cosmological evolution remains independent of the form of the chosen field, whether it is a scalar or a tachyon.

  2. Narrowing the field

    DEFF Research Database (Denmark)

    Knudsen, Bo Nissen

    The printed place-name series Danmarks Stednavne (Place-names of Denmark) has been published since 1922, and in 2013 volume 26 was released. Still only about 2/3 of the area of Denmark is covered by the series. Since 2009 a parallel effort has been made to digitalise the series through scanning...... and human-assisted character recognition – and place-name data from the rest of the country, derived from cadastral databases and a database of medieval settlement names, has been added while doing it. The resulting database, currently holding about 200,000 entries, is published at www....... As of now, no less than 45 different database fields have been found necessary to structure the information found in a single place-name entry – some fields mandatory, some nonmandatory. And using a relational database structure, some fields have multiple occurrences within one entry (i.e. multiple source...

  3. Strong Field Spherical Dynamos

    CERN Document Server

    Dormy, Emmanuel

    2014-01-01

    Numerical models of the geodynamo are usually classified in two categories: those denominated dipolar modes, observed when the inertial term is small enough, and multipolar fluctuating dynamos, for stronger forcing. I show that a third dynamo branch corresponding to a dominant force balance between the Coriolis force and the Lorentz force can be produced numerically. This force balance is usually referred to as the strong field limit. This solution co-exists with the often described viscous branch. Direct numerical simulations exhibit a transition from a weak-field dynamo branch, in which viscous effects set the dominant length scale, and the strong field branch in which viscous and inertial effects are largely negligible. These results indicate that a distinguished limit needs to be sought to produce numerical models relevant to the geodynamo and that the usual approach of minimizing the magnetic Prandtl number (ratio of the fluid kinematic viscosity to its magnetic diffusivity) at a given Ekman number is mi...

  4. Electromagnetic fields and waves

    CERN Document Server

    Iskander, Magdy F

    2013-01-01

    The latest edition of Electromagnetic Fields and Waves retains an authoritative, balanced approach, in-depth coverage, extensive analysis, and use of computational techniques to provide a complete understanding of electromagnetic—important to all electrical engineering students. An essential feature of this innovative text is the early introduction of Maxwell's equations, together with the quantifying experimental observations made by the pioneers who discovered electromagnetics. This approach directly links the mathematical relations in Maxwell's equations to real experiments and facilitates a fundamental understanding of wave propagation and use in modern practical applications, especially in today's wireless world. New and expanded topics include the conceptual relationship between Coulomb's law and Gauss's law for calculating electric fields, the relationship between Biot-Savart's and Ampere's laws and their use in calculating magnetic fields from current sources, the development of Faraday's law from e...

  5. Microbial field pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Coates, J.D.; Chisholm, J.L.

    1993-05-01

    A multi-well microbially enhanced oil recovery field pilot has been performed in the Southeast Vassar Vertz Sand Unit in Payne County, Oklahoma. The primary emphasis of the experiment was preferential plugging of high permeability zones for the purpose of improving waterflood sweep efficiency. Studies were performed to determine reservoir chemistry, ecology, and indigenous bacteria populations. Growth experiments were used to select a nutrient system compatible with the reservoir that encouraged growth of a group of indigenous nitrate-using bacteria and inhibit growth of sulfate-reducing bacteria. A specific field pilot area behind an active line drive waterflood was selected. Surface facilities were designed and installed. Injection protocols of bulk nutrient materials were prepared to facilitate uniform distribution of nutrients within the pilot area. By the end of December, 1991, 82.5 tons (75.0 tonnes) of nutrients had been injected in the field. A tracer test identified significant heterogeneity in the SEVVSU and made it necessary to monitor additional production wells in the field. The tracer tests and changes in production behavior indicate the additional production wells monitored during the field trial were also affected. Eighty two and one half barrels (13.1 m[sup 3]) of tertiary oil have been recovered. Microbial activity has increased CO[sub 2] content as indicated by increased alkalinity. A temporary rise in sulfide concentration was experienced. These indicate an active microbial community was generated in the field by the nutrient injection. Pilot area interwell pressure interference test results showed that significant permeability reduction occurred. The interwell permeabilities in the pilot area between the injector and the three pilot production wells were made more uniform which indicates a successful preferential plugging enhanced oil recovery project.

  6. Electromagnetic fields and their impacts

    Science.gov (United States)

    Prša, M. A.; Kasaš-Lažetić, K. K.

    2018-01-01

    The main goal of this paper is to briefly recall some different electromagnetic field definitions, some macroscopic sources of electromagnetic fields, electromagnetic fields classification regarding time dependences, and the ways of field determination in concrete cases. After that, all the mechanisms of interaction between electromagnetic field and substance, on atomic level, are described in details. Interaction between substance and electric field is investigated separately from the substance and magnetic field interaction. It is demonstrated that, in all cases of the unique electromagnetic field, total interaction can be treated as a superposition of two separated interactions. Finally, the main electromagnetic fields surrounding us is cited and discussed.

  7. Electromagnetic fields and interactions

    CERN Document Server

    Becker, Richard L

    1964-01-01

    For more than a century, ""Becker"" and its forerunner, ""Abraham-Becker,"" have served as the bible of electromagnetic theory for countless students. This definitive translation of the physics classic features both volumes of the original text.Volume I, on electromagnetic theory, includes an introduction to vector and tensor calculus, the electrostatic field, electric current and the field, and the theory of relativity. The second volume comprises a self-contained introduction to quantum theory that covers the classical principles of electron theory and quantum mechanics, problems involving

  8. Mapping the Field

    DEFF Research Database (Denmark)

    Goerres, Achim; Vanhuysse, Pieter

    2012-01-01

    Whereas the call for a political science based study of older people and ageing is not new (Cutler 1977; Heclo 1988), relatively little unified progress has been made so far. This chapter maps the field of generational politics and introduces our edited volume "Ageing Populations in Post-Industri......Whereas the call for a political science based study of older people and ageing is not new (Cutler 1977; Heclo 1988), relatively little unified progress has been made so far. This chapter maps the field of generational politics and introduces our edited volume "Ageing Populations in Post...

  9. Mean Field ICA

    DEFF Research Database (Denmark)

    Petersen, Kaare Brandt

    2006-01-01

    This thesis describes investigations and improvements of a technique for Independent Component Analysis (ICA), called "Mean Field ICA". The main focus of the thesis is the optimization part of the algorithm, the so-called "EM algorithm". Using different approaches it is demonstrated that the EM...... Gradient Recipe is applicable to a wide selection of models. Furthermore, the Mean Field ICA model is extended to incorporate ltering over time in a so-called "convolutive ICA" model. Finally, by using mixture of Gaussians as source priors, the generative and ltering approach to ICA is compared...

  10. DSM-5 field survey

    DEFF Research Database (Denmark)

    Lochner, Christine; Grant, Jon E; Odlaug, Brian Lawrence

    2012-01-01

    Pathologic skin picking (skin picking disorder [SPD]) is a prevalent and disabling condition, which has received increasing study. It is timely to consider including SPD in DSM-5. The aim of this field survey was to investigate possible diagnostic criteria for SPD.......Pathologic skin picking (skin picking disorder [SPD]) is a prevalent and disabling condition, which has received increasing study. It is timely to consider including SPD in DSM-5. The aim of this field survey was to investigate possible diagnostic criteria for SPD....

  11. Quantum field theory

    CERN Document Server

    Mandl, Franz

    2010-01-01

    Following on from the successful first (1984) and revised (1993) editions, this extended and revised text is designed as a short and simple introduction to quantum field theory for final year physics students and for postgraduate students beginning research in theoretical and experimental particle physics. The three main objectives of the book are to: Explain the basic physics and formalism of quantum field theory To make the reader proficient in theory calculations using Feynman diagrams To introduce the reader to gauge theories, which play a central role in elementary particle physic

  12. Excitation of transient lobe cell convection and auroral arc at the cusp poleward boundary during a transition of the interplanetary magnetic field from south to north

    Directory of Open Access Journals (Sweden)

    P. E. Sandholt

    2001-05-01

    Full Text Available We document the activation of transient polar arcs emanating from the cusp within a 15 min long intermediate phase during the transition from a standard two-cell convection pattern, representative of a strongly southward interplanetary magnetic field (IMF, to a "reverse" two-cell pattern, representative of strongly northward IMF conditions. During the 2–3 min lifetime of the arc, its base in the cusp, appearing as a bright spot, moved eastward toward noon by ~ 300 km. As the arc moved, it left in its "wake" enhanced cusp precipitation. The polar arc is a tracer of the activation of a lobe convection cell with clockwise vorticity, intruding into the previously established large-scale distorted two-cell pattern, due to an episode of localized lobe reconnection. The lobe cell gives rise to strong flow shear (converging electric field and an associated sheet of outflowing field-aligned current, which is manifested by the polar arc. The enhanced cusp precipitation represents, in our view, the ionospheric footprint of the lobe reconnection process.Key words. Magnetospheric physics (auroral phenomena; magnetopause, cusp, and boundary layers; plasma convection

  13. Field of Vision - Vehicles

    Science.gov (United States)

    2017-05-11

    observer to the ground for a 95th percentile male and a 5th percentile female . The dimensions of the vehicle should also be taken. 4. TEST...field of vision Gd ground distance MIL-STD Military Standard SAE Society of Automotive Engineers Sd stadia rod distance from the center of the...

  14. Superspace conformal field theory

    Energy Technology Data Exchange (ETDEWEB)

    Quella, Thomas [Koeln Univ. (Germany). Inst. fuer Theoretische Physik; Schomerus, Volker [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2013-07-15

    Conformal sigma models and WZW models on coset superspaces provide important examples of logarithmic conformal field theories. They possess many applications to problems in string and condensed matter theory. We review recent results and developments, including the general construction of WZW models on type I supergroups, the classification of conformal sigma models and their embedding into string theory.

  15. What Are Electromagnetic Fields?

    Science.gov (United States)

    ... them to quickly heat food. At radio frequencies, electric and magnetic fields are closely interrelated and we typically measure their levels as power densities in watts per square metre (W/m 2 ). Key points: The electromagnetic spectrum encompasses both natural and ...

  16. Tachyon field in cosmology

    Indian Academy of Sciences (India)

    requirements. For a viable model we require fine tuning of parameters comparable to that in ACDM or in quintessence models. For the exponential potential, the accelerated phase is followed by a phase with a(t) o t2/3 thus eliminating a future horizon. Keywords. Cosmology; tachyon field; dark energy; structure formation.

  17. [Field Learning Activities].

    Science.gov (United States)

    Nolde Forest Environmental Education Center, Reading, PA.

    Seventy field activities, pertinent to outdoor, environmental studies, are described in this compilation. Designed for elementary and junior high school students, the activities cover many discipline areas--science, social studies, language arts, health, history, mathematics, and art--and many are multidisciplinary in use. Topics range from soil…

  18. Fields of Fuel

    Science.gov (United States)

    Russ, Rosemary S.; Wangen, Steve; Nye, D. Leith; Shapiro, R. Benjamin; Strinz, Will; Ferris, Michael

    2015-01-01

    To help teachers engage students in discussions about sustainability, the authors designed Fields of Fuel, a multiplayer, web-based simulation game that allows players to explore the environmental and economic trade-offs of a realistic sustainable system. Computer-based simulations of real-world phenomena engage students and have been shown to…

  19. Field Guide to Radiometry

    CERN Document Server

    Grant, Barbara

    2011-01-01

    Written from a systems engineering perspective, this SPIE Field Guide covers topics in optical radiation propagation, material properties, sources, detectors, system components, measurement, calibration, and photometry. The book's organization and extensive collection of diagrams, tables, and graphs will enable the reader to efficiently identify and apply relevant information to radiometric problems arising amid the demands of today's fast-paced technical environment.

  20. Warp Field Mechanics 101

    Science.gov (United States)

    White, Harold

    2011-01-01

    This paper will begin with a short review of the Alcubierre warp drive metric and describes how the phenomenon might work based on the original paper. The canonical form of the metric was developed and published in [6] which provided key insight into the field potential and boost for the field which remedied a critical paradox in the original Alcubierre concept of operations. A modified concept of operations based on the canonical form of the metric that remedies the paradox is presented and discussed. The idea of a warp drive in higher dimensional space-time (manifold) will then be briefly considered by comparing the null-like geodesics of the Alcubierre metric to the Chung-Freese metric to illustrate the mathematical role of hyperspace coordinates. The net effect of using a warp drive technology coupled with conventional propulsion systems on an exploration mission will be discussed using the nomenclature of early mission planning. Finally, an overview of the warp field interferometer test bed being implemented in the Advanced Propulsion Physics Laboratory: Eagleworks (APPL:E) at the Johnson Space Center will be detailed. While warp field mechanics has not had a Chicago Pile moment, the tools necessary to detect a modest instance of the phenomenon are near at hand.

  1. Device for measuring electric fields

    Science.gov (United States)

    Levine, S. H.; Harrison, S. R.

    1972-01-01

    Measurement of low-intensity electric fields in space and in presence of weak magnetic fields is accomplished by utilizing a device which permits determination of the extent a beam of cesium ions is deflected by an electric field.

  2. Application of polarization ellipse technique for analysis of ULF magnetic fields from two distant stations in Koyna-Warna seismoactive region, West India

    Directory of Open Access Journals (Sweden)

    F. Dudkin

    2010-07-01

    Full Text Available A new approach is developed to find the source azimuth of the ultra low frequency (ULF electromagnetic (EM signals believed to be emanating from well defined seismic zone. The method is test applied on magnetic data procured from the seismoactive region of Koyna-Warna, known for prolonged reservoir triggered seismicity. Extremely low-noise, high-sensitivity LEMI-30 search coil magnetometers were used to measure simultaneously the vector magnetic field in the frequency range 0.001–32 Hz at two stations, the one located within and another ~100 km away from the seismic active zone. During the observation campaign extending from 15 March to 30 June 2006 two earthquakes (EQs of magnitude (ML>4 occurred, which are searched for the presence of precursory EM signals.

    Comparison of polarization ellipses (PE parameters formed by the magnetic field components at the measurement stations, in select frequency bands, allows discrimination of seismo-EM signals from the natural background ULF signals of magnetospheric/ionospheric origin. The magnetic field components corresponding to spectral bands dominated by seismo-EM fields define the PE plane which at any instant contains the source of the EM fields. Intersection lines of such defined PE planes for distant observation stations clutter in to the source region. Approximating the magnetic-dipole configuration for the source, the magnetic field components along the intersection lines suggest that azimuth of the EM source align in the NNW-SSE direction. This direction well coincides with the orientation of nodal plane of normal fault plane mechanism for the two largest EQs recorded during the campaign. More significantly the correspondence of this direction with the tectonic controlled trend in local seismicity, it has been surmised that high pressure fluid flow along the fault that facilitate EQs in the region may also be the source mechanism for EM fields by electrokinetic effect.

  3. Gravitational Field Shielding by Scalar Field and Type II Superconductors

    Directory of Open Access Journals (Sweden)

    Zhang B. J.

    2013-01-01

    Full Text Available The gravitational field shielding by scalar field and type II superconductors are theoret- ically investigated. In accord with the well-developed five-dimensional fully covariant Kaluza-Klein theory with a scalar field, which unifies the Einsteinian general relativity and Maxwellian electromagnetic theory, the scalar field cannot only polarize the space as shown previously, but also flatten the space as indicated recently. The polariza- tion of space decreases the electromagnetic field by increasing the equivalent vacuum permittivity constant, while the flattening of space decreases the gravitational field by decreasing the equivalent gravitational constant. In other words, the scalar field can be also employed to shield the gravitational field. A strong scalar field significantly shield the gravitational field by largely decreasing the equivalent gravitational constant. According to the theory of gravitational field shielding by scalar field, the weight loss experimentally detected for a sample near a rotating ceramic disk at very low tempera- ture can be explained as the shielding of the Earth gravitational field by the Ginzburg- Landau scalar field, which is produced by the type II superconductors. The significant shielding of gravitational field by scalar field produced by superconductors may lead to a new spaceflight technology in future.

  4. On Scale and Fields

    DEFF Research Database (Denmark)

    Kadish, David

    2017-01-01

    is being undertaken with the adoption of interventionist strategies in urban agricultural practices like seed bombing and guerrilla gardening. At the same time, there is a proliferation of media-connected and miniature autonomous drones and robotics. Might this combination be the foundation for a novel......This paper explores thematic parallels between artistic and agricultural practices in the postwar period to establish a link to media art and cultural practices that are currently emerging in urban agriculture. Industrial agriculture has roots in the post-WWII abundance of mechanical and chemical......-scale agricultural systems that range from spreading pests and diseases to poor global distribution of concentrated regional food wealth. That the conversion of vegetatively diverse farmland into monochromatic fields was popularized at the same time as the arrival of colour field paintings like Barnett Newman...

  5. Particles and quantum fields

    CERN Document Server

    Kleinert, Hagen

    2016-01-01

    This is an introductory book on elementary particles and their interactions. It starts out with many-body Schrödinger theory and second quantization and leads, via its generalization, to relativistic fields of various spins and to gravity. The text begins with the best known quantum field theory so far, the quantum electrodynamics of photon and electrons (QED). It continues by developing the theory of strong interactions between the elementary constituents of matter (quarks). This is possible due to the property called asymptotic freedom. On the way one has to tackle the problem of removing various infinities by renormalization. The divergent sums of infinitely many diagrams are performed with the renormalization group or by variational perturbation theory (VPT). The latter is an outcome of the Feynman-Kleinert variational approach to path integrals discussed in two earlier books of the author, one representing a comprehensive treatise on path integrals, the other dealing with critial phenomena. Unlike ordin...

  6. Microcontinuum field theories

    CERN Document Server

    Eringen, A Cemal

    1999-01-01

    Microcontinuum field theories constitute an extension of classical field theories -- of elastic bodies, deformations, electromagnetism, and the like -- to microscopic spaces and short time scales. Material bodies are here viewed as collections of large numbers of deformable particles, much as each volume element of a fluid in statistical mechanics is viewed as consisting of a large number of small particles for which statistical laws are valid. Classical continuum theories are valid when the characteristic length associated with external forces or stimuli is much larger than any internal scale of the body under consideration. When the characteristic lengths are comparable, however, the response of the individual constituents becomes important, for example, in considering the fluid or elastic properties of blood, porous media, polymers, liquid crystals, slurries, and composite materials. This volume is concerned with the kinematics of microcontinua. It begins with a discussion of strain, stress tensors, balanc...

  7. Quantum Field Theory

    CERN Document Server

    Zeidler, Eberhard

    This is the first volume of a modern introduction to quantum field theory which addresses both mathematicians and physicists ranging from advanced undergraduate students to professional scientists. The book tries to bridge the existing gap between the different languages used by mathematicians and physicists. For students of mathematics it is shown that detailed knowledge of the physical background helps to motivate the mathematical subjects and to discover interesting interrelationships between quite different mathematical topics. For students of physics, fairly advanced mathematics is presented, which is beyond the usual curriculum in physics. It is the author's goal to present the state of the art of realizing Einstein's dream of a unified theory for the four fundamental forces in the universe (gravitational, electromagnetic, strong, and weak interaction). From the reviews: "… Quantum field theory is one of the great intellectual edifices in the history of human thought. … This volume differs from othe...

  8. ISR Radial Field Magnet

    CERN Multimedia

    1983-01-01

    There were 37 (normal) + 3 (special) Radial Field magnets in the ISR to adjust vertically the closed orbit. Gap heights and strengths were 200 mm and .12 Tm in the normal magnets, 220 mm and .18 Tm in the special ones. The core length was 430 mm in both types. Due to their small length as compared to the gap heights the end fringe field errors were very important and had to be compensated by suitably shaping the poles. In order to save on cables, as these magnets were located very far from their power supplies, the coils of the normal type magnets were formed by many turns of solid cpper conductor with some interleaved layers of hollow conductor directly cooled by circulating water

  9. Towards a unified theory for immunogenetic systems. I. Probing the serologic field--a meta-serologic approach.

    Science.gov (United States)

    Hirschfeld, J

    1977-01-01

    A serologic field (SEF) is produced by the in vitro studies of antibody-antigen interactions and usually includes serologic information processing (SIF). SIF can be regarded as the process whereby essentially "meaningless" raw data or experimental observables emanating from an input reality are structuralized and hence falsified into a "meaningful" pattern, Gestalt or output image. According to this "black box model", different "fact categories" (FC) can be identified in SEF. Traditional serology generally confounds its FC whereby fact category mistakes (FCM) are produced. Some FCM are structurally similar to the description of "mice" as four-letter animals or as a four-legged word--i.e. facts about "thing-properties" (animals, legs) are confounded with facts about "language-properties" (letters, words). In SEF, antibody and antigen molecules (thing-properties) are similarly endowed with "empty symbols" (language-properties). Due to such FCM, radically new meanings are assigned to experimental observables if the serologic language and/or theory is changed. The present meta-serologic approach consists of the design of a meta-serologic symbol language (SL-2) which includes the contemporary (simple-complex) conceptual framework (language and theory) as a limiting case. Consequently, some truly radical and revolutionary Gestalt switches will be generated when a specified SEF is mapped onto SL-2.

  10. AWARE Wide Field View

    Science.gov (United States)

    2016-04-29

    RGB colors to the standard sRGB to allow spectrally consistent colors on monitors for viewing . Finally, the images from each sensor are corrected based ...on the exposure time used and the calibrated sensitivity of each image sensor, again based on the flat field calibration, to allow viewing of imagery...prediction is scaled based on available bandwidth and the computational resources of the cluster. In addition to the interface described in the

  11. Phase Field Fracture Mechanics.

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Brett Anthony [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-11-01

    For this assignment, a newer technique of fracture mechanics using a phase field approach, will be examined and compared with experimental data for a bend test and a tension test. The software being used is Sierra Solid Mechanics, an implicit/explicit finite element code developed at Sandia National Labs in Albuquerque, New Mexico. The bend test experimental data was also obtained at Sandia Labs while the tension test data was found in a report online from Purdue University.

  12. Microbial field pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Chisholm, J.L.

    1992-03-01

    The objective of this project is to perform a microbial enhanced oil recovery field pilot in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate reducing bacteria will be stimulated to selectively plug flow paths which have been referentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. This report covers progress made during the second year, January 1, 1990 to December 31, 1990, of the Microbial Field Pilot Study project. Information on reservoir ecology, surface facilities design, operation of the unit, core experiments, modeling of microbial processes, and reservoir characterization and simulation are presented in the report. To better understand the ecology of the target reservoir, additional analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. The results of the produced and injected water analysis show increasing sulfide concentrations with respect to time. In March of 1990 Mesa Limited Partnership sold their interest in the SEVVSU to Sullivan and Company. In April, Sullivan and Company assumed operation of the field. The facilities for the field operation of the pilot were refined and implementation was begun. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. The experiments were performed at SEVVSU temperature using fluids and inoculum from the unit. The model described in last year's report was further validated using results from a core flood experiment. The model was able to simulate the results of one of the core flood experiments with good quality.

  13. Microbial field pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Chisholm, J.L.

    1992-03-01

    The objective of this project is to perform a microbial enhanced oil recovery field pilot in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate reducing bacteria will be stimulated to selectively plug flow paths which have been referentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. This report covers progress made during the second year, January 1, 1990 to December 31, 1990, of the Microbial Field Pilot Study project. Information on reservoir ecology, surface facilities design, operation of the unit, core experiments, modeling of microbial processes, and reservoir characterization and simulation are presented in the report. To better understand the ecology of the target reservoir, additional analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. The results of the produced and injected water analysis show increasing sulfide concentrations with respect to time. In March of 1990 Mesa Limited Partnership sold their interest in the SEVVSU to Sullivan and Company. In April, Sullivan and Company assumed operation of the field. The facilities for the field operation of the pilot were refined and implementation was begun. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. The experiments were performed at SEVVSU temperature using fluids and inoculum from the unit. The model described in last year`s report was further validated using results from a core flood experiment. The model was able to simulate the results of one of the core flood experiments with good quality.

  14. Securing Near Field Communication

    OpenAIRE

    Kortvedt, Henning Siitonen

    2009-01-01

    Near Field Communication (NFC) specifies a standard for a wireless communication protocol enabling data transfer by keeping two devices close together, about 10 cm maximum. NFC is designed for integration with mobile phones, which can communicate with other NFC phones (peer-to-peer) or read information on tags and cards (reader). An NFC device can also be put in card emulation mode, to offer compatibility with other contactless smart card standards. This enables NFC devices to replace traditi...

  15. Visualisation of data fields

    OpenAIRE

    David, Jiří; Heger, Milan; Vrožina, Milan; Válek, Ladislav

    2010-01-01

    Visualization of production data and information based on on-line data acquisition from production process represents at present an integral part of visualization management in many industrial lines. In this paper we described principles and possibilities of software application for visualization of data fields created on department of automation and computer technology in metallurgy, VˇSB-TU Ostrava. The application is demonstrated on a visualization of abrasion of crystallizer o...

  16. Determining Radium-226 concentration from Radon-222 emanation in building materials: a theoretical model

    Energy Technology Data Exchange (ETDEWEB)

    Barreto, Rafael C.; Perna, Allan F.N.; Narloch, Danielle C.; Del Claro, Flavia; Correa, Janine N.; Paschuk, Sergei A., E-mail: baarreth@gmail.com, E-mail: allan_perna@hotmail.com, E-mail: daninarloch@hotmail.com, E-mail: aviadelclaro@gmail.com, E-mail: janine_nicolosi@hotmail.com, E-mail: spaschuk@gmail.com [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil). Departamento Academico de Fisica e Departamento Academico de Construcao Civil

    2017-07-01

    It was developed an improved theoretical model capable to estimate the radium concentration in building materials solely measuring the radon-222 concentration in a con ned atmosphere. This non-destructive technique is not limited by the size of the samples, and it intrinsically includes back diffusion. The resulting equation provides the exact solution for the concentration of radon-222 as a function of time and distance in one dimension. The effective concentration of radium-226 is a fit parameter of this equation. In order to reduce its complexity, this equation was simplified considering two cases: low diffusion in the building material compared to the air, and a building material initially saturated with radon-222. These simplified versions of the exact one dimension solution were used to t experimental data. Radon-222 concentration was continuously measured for twelve days with an AlphaGUARD{sup TM} detector, located at the Laboratory of Applied Nuclear Physics at Universidade Tecnologica Federal do Parana (UTFPR). This model was applied to two different materials: cement mortar and concrete, which results were respectively (15:7 ±8:3) Bq=kg and (10:5±2:4) Bq=kg for the radium-226 effective concentration. This estimation was confronted with the direct measurements of radium in the same materials (same sources) using gamma-ray spectrometry, fulfilled at Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), which results were respectively (13:81±0:23) Bq=kg and (12:61±0:22) Bq=kg. (author)

  17. Real estate ads in Emei music frog vocalizations: female preference for calls emanating from burrows.

    Science.gov (United States)

    Cui, Jianguo; Tang, Yezhong; Narins, Peter M

    2012-06-23

    During female mate choice, both the male's phenotype and resources (e.g. his nest) contribute to the chooser's fitness. Animals other than humans are not known to advertise resource characteristics to potential mates through vocal communication; although in some species of anurans and birds, females do evaluate male qualities through vocal communication. Here, we demonstrate that calls of the male Emei music frog (Babina dauchina), vocalizing from male-built nests, reflect nest structure information that can be recognized by females. Inside-nest calls consisted of notes with energy concentrated at lower frequency ranges and longer note durations when compared with outside-nest calls. Centre frequencies and note durations of the inside calls positively correlate with the area of the burrow entrance and the depth of the burrow, respectively. When given a choice between outside and inside calls played back alternately, more than 70 per cent of the females (33/47) chose inside calls. These results demonstrate that males of this species faithfully advertise whether or not they possess a nest to potential mates by vocal communication, which probably facilitates optimal mate selection by females. These results revealed a novel function of advertisement calls, which is consistent with the wide variation in both call complexity and social behaviour within amphibians.

  18. Human skin emanations in the host-seeking behaviour of the malaria mosquito Anopheles gambiae

    NARCIS (Netherlands)

    Braks, M.

    1999-01-01

    Malaria is an infectious disease caused by a parasite ( Plasmodium spp.) that is transmitted between human individuals by mosquitoes, belonging to the order of insects, Diptera, family of Culicidae (mosquitoes) and genus of Anopheles (malaria

  19. Emanation thermal analysis study of synthetic gibbsite - Evaluation of experimental ETA results by mathematical modelling

    Czech Academy of Sciences Publication Activity Database

    Balek, Vladimír; Šubrt, Jan; Rouquerol, J.; Llewellyn, P.; Zeléňák, V.; Bountsewa, I. M.; Beckman, I. N.; Györyová, K.

    2003-01-01

    Roč. 71, č. 3 (2003), s. 773-782 2003 ISSN 1388-6150 R&D Projects: GA MŠk LN00A028; GA MŠk ME 344 Institutional research plan: CEZ:AV0Z4032918 Keywords : ETA * gibbsite * mathematical modelling Subject RIV: CA - Inorganic Chemistry Impact factor: 1.094, year: 2003

  20. A Review of Radon Emanation and Mobilization in Minerals and Rocks.

    Science.gov (United States)

    1987-09-01

    the breakdown of rock matrix and mineral degrada- tion during weathering. f. Although some common accessory minerals (Table 3) have high uranium...damage. For example, zircon inclusions in feldspars fail to I show the pleochroic haloes so common when zircon is hosted in biotite ; suggesting an... Accessory Zircons and the Petro- graphic Significant of their Uranium Decay Age. Schweiz. Mineral . und Petrol. Mitt., No. 43, p 235-257. Grunenfelder, M. H