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Sample records for ps beam diameter

  1. LS1 Report: PS beams are back!

    CERN Multimedia

    Katarina Anthony & Anaïs Schaeffer

    2014-01-01

    For the first time in over 15 months, there are beams back in the PS. Making their first tour of the accelerator today, 20 June, their injection marks the end of weeks of cold checkouts and hardware commissioning in the PS.   The CERN Control Centre (CCC) is back in business: people gather to restart the LHC injectors, today the PS. Since hardware commissioning was wrapped up on 23 May, the Operations Group (BE-OP) has been conducting cold checkouts on the PS. This involves switching on all of the machine's systems, verifying that they respond to commands by OP and ensuring they are calibrated to beam timings. "These verifications were done, in part, during the hardware commissioning dry runs," says Rende Steerenberg, PS section leader. "But the cold checkouts are on a much larger scale, as we act as if there is beam in the whole machine. We placed a full load on the controls system, cooling, networks, etc. in order to setup the accelerator in the most realis...

  2. Definition of Beam Diameter for Electron Beam Welding

    Energy Technology Data Exchange (ETDEWEB)

    Burgardt, Paul [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pierce, Stanley W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dvornak, Matthew John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-03-11

    It is useful to characterize the dimensions of the electron beam during process development for electron beam welding applications. Analysis of the behavior of electron beam welds is simplest when a single number can be assigned to the beam properties that describes the size of the beam spot; this value we generically call the “beam diameter”. This approach has worked well for most applications and electron beam welding machines with the weld dimensions (width and depth) correlating well with the beam diameter. However, in recent weld development for a refractory alloy, Ta-10W, welded with a low voltage electron beam machine (LVEB), it was found that the weld dimensions (weld penetration and weld width) did not correlate well with the beam diameter and especially with the experimentally determined sharp focus point. These data suggest that the presently used definition of beam diameter may not be optimal for all applications. The possible reasons for this discrepancy and a suggested possible alternative diameter definition is the subject of this paper.

  3. Specification of the Beam Position Measurement in the PS Machine

    CERN Document Server

    Bravin, Enrico; Chanel, M; Ludwig, M; Métral, Elias; Métral, G; Potier, J P; Raich, U; Scrivens, R; Steerenberg, R; CERN. Geneva. AB Department

    2003-01-01

    This specification, drawn up by the instrumentation specification board 2, describes the requirements concerning orbit and trajectory measurements in the PS machine. The orbit measurement and the trajectory measurement are both indispensable in order to be able to guarantee the correct beam quality for beams like LHC, the future Grand Sasso beam, the nTOF beam and surely the combined operation of the nTOF beam and the East Area beam.

  4. Interleaving of beam lines inside the PS tunnel

    CERN Multimedia

    1983-01-01

    View against the direction of the proton beams. The PS ring (section 26) is on the left. The injection tunnel for LEAR leaving from here has increased the trafic in this already busy area where the two Linacs and the transfer tunnel leading to the SPS, ISR and AA join the PS ring (cf. photo 7802260, 7802261, Annual Report 1981, p. 89, fig. 12).

  5. The PS complex produces the nominal LHC beam

    CERN Document Server

    Benedikt, Michael; Borburgh, J; Cappi, R; Chanel, M; Chohan, V; Cyvoct, G; Garoby, R; Grier, D G; Gruber, J; Hancock, S; Hill, C E; Jensen, E; Krusche, A; Lindroos, M; Métral, Elias; Métral, G; Metzmacher, K D; Olsfors, J; Pedersen, F; Raich, U; Riunaud, J P; Royer, J P; Sassowsky, M; Schindl, Karlheinz; Schönauer, Horst Otto; Thivent, M; Ullrich, H M; Völker, F V; Vretenar, Maurizio; Barnes, M; Blackmore, E W; Cifarelli, F; Clark, G; Jones, F; Koscielniak, Shane Rupert; Mammarella, F; Mitra, A; Poirier, R; Reiniger, K W; Ries, T C

    2000-01-01

    The LHC [1] will be supplied, via the SPS, with protons from the pre-injector chain comprising Linac2, PS Booster (PSB) and PS. These accelerators have under-gone a major upgrading programme [2] during the last five years so as to meet the stringent requirements of the LHC. These imply that many high-intensity bunches of small emittance and tight spacing (25 ns) be available at the PS extraction energy (25 GeV). The upgrading project involved an increase of Linac2 current, new RF systems in the PSB and the PS, raising the PSB energy from 1 to 1.4 GeV, two-batch filling of the PS and the installation of high-resolution beam profile measurement devices. With the project entering its final phase and most of the newly installed hardware now being operational, the emphasis switches to producing the nominal LHC beam and tackling the associated beam physics problems. While a beam with transverse characteristics better than nominal has been obtained, the longitudinal density still needs to be increased. An alternativ...

  6. Beam Quality Preservation in the CERN PS-SPS Complex

    CERN Multimedia

    Arduini, Gianluigi

    2004-01-01

    The LHC will require beams of unprecedented transverse and longitudinal brightness. Their production imposes tight constraints on the emittance growth in each element of the LHC injector chain, namely the PS-SPS Accelerator Complex. The problems encountered at the different stages of the acceleration in the complex span a wide range of topics, such as injection matching, RF gymnastics, space charge, transverse and longitudinal single- and coupled-bunch instabilities, and electron cloud effects. The measurement techniques developed and applied to identify and study the various sources of emittance dilution to the high precision required for the LHC beams and the solutions found to control such phenomena are illustrated.

  7. Search for Decays of Heavy Neutrinos with the PS Beam

    CERN Multimedia

    2002-01-01

    The experiment searches for neutrino decay, primarily into the e|+e|-@n^e and @g@g@n^e modes. Neutrino masses in the region between 1 and 400~MeV will be explored. The beam used is the neutrino PS beam used for the oscillation experiments. The apparatus consists of a decay volume @=30~m long and a calorimeter @=8~radiation lengths thick and @=20~m|2 in surface. The detectors are flash-tube modules of the type developed at Saclay for the proton-stability experiment. Scintillator hodoscopes give the timing information necessary for the trigger logic and background rejection.

  8. LS1 Report: PS Booster prepares for beam

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    With Linac2 already up and running, the countdown to beam in the LHC has begun! The next in line is the PS Booster, which will close up shop to engineers early next week. The injector will be handed over to the Operations Group who are tasked with getting it ready for active duty.   Taken as we approach the end of LS1 activities, this image shows where protons will soon be injected from Linac2 into the four PS Booster rings. Over the coming two months, the Operations Group will be putting the Booster's new elements through their paces. "Because of the wide range of upgrades and repairs carried out in the Booster, we have a very full schedule of tests planned for the machine," says Bettina Mikulec, PS Booster Engineer in Charge. "We will begin with cold checks; these are a wide range of tests carried out without beam, including system tests with power on/off and with varying settings, as well as verification of the controls system and timings." Amon...

  9. Beam lines from Linac 1 to PS and Booster

    CERN Multimedia

    CERN PhotoLab

    1978-01-01

    View against the direction of the proton beams. The 50 MeV Linac 1 is behind the concrete wall. Its beam emerges from the hole near the centre of the picture. A switching magnet directs the beam either to the PS (to the right in the sense of the beam; original injection line), or lets it go straight on to the Booster (originally 800 MeV, now 1.4 GeV). The huge drum in the line to the Booster is a "debuncher", driven by the 200 MHz RF of the linac. It reduces the beam's momentum spread. This was the last year of Linac 1 as provider of protons to the Booster. Linac 2, nearly completed at the time of this picture, took up trial delivery at the end of 1978, and routine delivery in 1979. The beam line from Linac 2, barely visible here, can be clearly seen on 7802260. Linac 1 had a second life as an ion accelerator.

  10. Recent improvements of the RF Beam control for LHC-type beams in the CERN PS

    CERN Document Server

    Damerau, H; Schokker, M

    2010-01-01

    To cope with the large variety of different beams for the LHC, the RF beam control in the CERN PS has evolved continuously to improve its flexibility and reliability. Single-bunch beams, several different multi-bunch beams with 25, 50 or 75 ns bunch spacing at ejection for LHC filling, as well as two lead-ion beam variants are now regularly produced in pulse-to-pulse operation. The multibunch beam control for protons can be easily re-adjusted from 0.25 · 1011 to 1.3 · 1011 particles per ejected bunch. Depending on the number of bunches injected from the PS Booster, the length of the ejected bunch train may vary from 8 to 72 bunches. This paper summarizes recent improvements in the low-level RF systems and gives an outlook on the future consolidation.

  11. Preparation of the beam for PS-MTE at the PSB

    CERN Document Server

    Chanel, M; CERN. Geneva. BE Department

    2009-01-01

    The Multi-Turn Extraction(MTE)1 at the PS requires, from the PSB, a beam(up to 6.5 1012 protons/ring) with a large horizontal emittance to better produce the five beamlets and a vertical emittance as small as possible. The ways to produce this beam and adjust the parameters are described in this note.

  12. Emittance control of the PS e ± beams using a robinson wiggler

    Science.gov (United States)

    Baconnier, Y.; Cappi, R.; Riunaud, J. P.; Umstätter, H. H.; Level, M. P.; Sommer, M.; Zyngier, H.

    1985-02-01

    In 1958 Robinson of the Cambridge electron accelerator (Massachusetts) proposed that a gradient wiggler magnet be used to stabilise naturally unstable electron and positron beams in combined function machines. In 1986 such a method is to be applied in the PS so that, besides its many other tasks, it may serve as an accelerator in the LEP injector chain. This paper describes a prototype of a gradient wiggler magnet designed and constructed at CERN. It reports the results of measurements obtained with proton beams in the PS to check the influence of the wiggler on beam optics and of measurements made with positron beams in DCI (LAL, Orsay, France) to check the damping variations produced by this wiggler. As predictions were confirmed by these measurements, three magnets of this type will be installed in the PS when it is part of the LEP injector chain.

  13. PS BOOSTER BEAM TESTS OF THE NEW DIGITAL BEAM CONTROL SYSTEM FOR LEIR

    CERN Document Server

    Angoletta, Maria Elena; Bento, J; De Long, J H; Findlay, A; Matuszkiewicz, P; Pedersen, F; Salom-Sarasqueta, A; CERN. Geneva. AB Department

    2005-01-01

    We have been developing a scaled-down prototype of the new digital beam control and cavity servoing system for CERN’s Low Energy Ion Ring (LEIR) slated for commissioning in 2005. The system’s hardware and software, developed as part of a CERN-BNL collaboration, are based on new all-digital technology already deployed at BNL's AGS Booster. The system relies on VME modules, carrying Digital Signal Processors (DSPs) as well as Field Programmable Gate Arrays (FPGAs), and daughter cards. New concepts deployed include software implementation, through DSPs & FPGAs, of functions traditionally executed by analogue hardware, such as reference-functions and timings generation. Additionally, a user-selectable digital data acquisition functionality provides diagnostic and troubleshoot access points, a new feature which is very useful in a digital system. The scaled-down prototype implements frequency program, radial steering, phase and radial loops capabilities and it has been tested in CERN's PS Booster (PSB) dur...

  14. Beam Break-up Instability in the CERN PS near Transition

    CERN Document Server

    Cappi, R; Métral, G

    2000-01-01

    Fast beam losses, due to a vertical coherent instability of high frequency, have been observed in the PS near transition energy, with the high-intensity single-bunch beam for the neutron Time-of-Flight facility (n-ToF). By increasing the longitudinal emittance, the beam could be stabilised. These phenomena can be described by the beam breakup theory, since near transition the longitudinal positions of particles are almost frozen, as in the linac case. Comparison between observations and theory, using Brandt and Gareyte's formula for single-bunch beam breakup in circular accelerators, shows good agreement.

  15. Injection Matching Studies using Turn by Turn Beam Profile Measurements in the CERN PS

    CERN Document Server

    Benedikt, Michael; Dutriat, C; Jansson, A; Giovannozzi, Massimo; Martini, M; Raich, U

    2001-01-01

    The very small emittance beam needed for the LHC requires that the emittance blow-up in its injector machines must be kept to a minimum. Mismatch upon the beam transfer from one machine to the next is a potential source of such blow-up. The CERN PS ring is equipped with 3 Secondary Emission Grids (SEM-Grids) which are used for emittance measurement at injection. One of these has been converted to a multi-turn mode, in which several tens of consecutive beam passages can be observed. This allows the study of mismatch between the PS-Booster and the PS. This paper describes the instrument and experimental results obtained during the last year.

  16. The beam-handling magnet system of the KEK-PS new experimental hall

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, K.H.; Yamanoi, Y.; Minakawa, M.; Noumi, H.; Ieiri, M.; Kato, Y.; Ishii, H.; Suzuki, Y.; Takasaki, M. (Physics Dept., National Lab. for High Energy Physics, 1-1 Oho, Tsukuba-shi, Ibaraki-ken 305 (JP)); Kato, K.; Yokoi, T. (Electromagnet Div., Tokin Corp., 6-7-1 Koriyama, Taihaku-ku, Sendai 982 (JP))

    1992-01-01

    Construction work of the new counter experimental hall of the KEK 12-GeV Proton Synchrotron (KEK-PS) was completed in December, 1990. The new hall was planned to be a mini kaon factory from the start. The beam-handling magnet system of the new hall was, thus, equipped with newly developed radiation resistant magnets in order to handle a high-intensity proton beam, as reported in MT11. another important point regarding high-intensity beam handling is to realize easy maintenance of the beam line. For this purpose, all magnets of the primary proton beam line were mounted on special base plates on which quick-disconnect devices for electric power, cooling water, and interlock signals were assembled. The vacuum connections of the beam ducts located at both ends of the magnet are also operated remotely. any magnet experiencing trouble can, thus, be easily removed from the beam line and repaired remotely. In this paper the authors summarize the new ideas and new technologies employed in the beam-handling magnet system in the new experimental hall of the KEK-PS, as well as the first beam commissioning results concerning the beam line.

  17. Study of transverse beam splitting for multi-turn extraction for the CERN PS2 ring

    CERN Document Server

    Giovannozzi, Massimo; CERN. Geneva. ATS Department

    2011-01-01

    In this paper a layout for the elements needed to split transversely the beam for a multi-turn extraction system in the PS2 ring is proposed and discussed. Additional sextupoles and octupoles are installed in one of the straight sections to generate the stable islands in the horizontal phase space. Scans over various beam dynamics quantities were performed to provide hints for an optimisation of the scheme. The results are presented and discussed in details.

  18. Linac4 Beam Characterization before Injection into the CERN PS Booster

    CERN Document Server

    Mikulec, B; Eshraqi, M; Hanke, K; Hermanns, T; Lombardi, A M; Raich, U

    2010-01-01

    Construction work for the new CERN linear accelerator, Linac4, started in October 2008. Linac4 will replace the existing Linac2 and provide an H− beam at 160 MeV (as opposed to the present 50 MeV proton beam) for injection into the CERN PS Booster (PSB). The charge-exchange H− injection combined with the higher beam energy will allow for an increase in beam brightness required for reaching the ultimate LHC luminosity. Commissioning of Linac4 and of the transfer line to the PSB is planned for the last quarter of 2012. Appropriate beam instrumentation is foreseen to provide transverse and longitudinal beam characterization at the exit of Linac4 and in two dedicated measurement lines located before injection into the PSB. A detailed description of the diagnostics set, especially of spectrometer and emittance meter, and the upgrade of the measurement lines for Linac4 commissioning and operation is presented.

  19. Emittance Measurements For Future LHC Beams Using The PS Booster Measurement Line

    CERN Document Server

    Abelleira, Jose; Mikulec, Bettina; Di Giovanni, Gian Piero; CERN. Geneva. ATS Department

    2017-01-01

    The CERN PS Booster measurement line contains three pairs of SEM grids separated by drift space that measures the beam size in both planes. The combined analysis of these grids allows calculating a value for the transverse beam emittances. The precision of such a measurement depends on the ratio of RMS beam size and wire spacing. Within the LIU-PSB upgrade the extraction kinetic energy of the PSB will be increased from the current 1.4 GeV to 2.0 GeV. This will result in smaller transverse beam sizes for some of the future beams. The present layout of the transverse emittance measurement line is reviewed to verify if it will satisfy future requirements.

  20. Polarimetry diagnostic on OMEGA EP using a 10-ps, 263-nm probe beam.

    Science.gov (United States)

    Davies, A; Haberberger, D; Boni, R; Ivancic, S; Brown, R; Froula, D H

    2014-11-01

    A polarimetry diagnostic was built and characterized for magnetic-field measurements in laser-plasma experiments on the OMEGA EP laser. This diagnostic was built into the existing 4ω (263-nm) probe system that employs a 10-ps laser pulse collected with an f/4 imaging system. The diagnostic measures the rotation of the probe beam's polarization. The polarimeter uses a Wollaston prism to split the probe beam into orthogonal polarization components. Spatially localized intensity variations between images indicate polarization rotation. Magnetic fields can be calculated by combining the polarimetry data with the measured plasma density profile obtained from angular filter refractometry.

  1. Simulation and observation of driven beam oscillations with space charge in the CERN PS Booster

    CERN Document Server

    McAteer, M; Benedetto, E; Carli, C; Findlay, A; Mikulec, B; Tomás, R

    2014-01-01

    As part of the LHC Injector Upgrade project, the CERN PS Booster will be required to operate at nearly doubled intensity with little allowable increase in emittance growth or beam loss. A campaign of nonlinear optics measurements from turn-by-turn trajectory measurements, with the goal of characterizing and then compensating for higher-order resonances, is planned for after Long Shutdown 1. The trajectory measurement system is expected initially to require high intensity beam in order to have good position measurement resolution, so understanding space charge effects will be important for optics analysis. We present the results of simulations of driven beam oscillations with space charge effects, and comparison with trial beam trajectory measurements.

  2. Electrical properties comparison of TiO2/PS/Si devices fabricated by spin coating and electron beam gun

    Science.gov (United States)

    Dariani, R. S.; Faraji, F.

    2016-04-01

    Three porous silicon (PS) samples with different porosities by electrochemical anodization are fabricated. Then, TiO2 nanoparticles are deposited on PS by two methods, spin coating and electron beam gun. I- V characteristics of all samples show diode behavior. Our result showed that transient current decreases with increasing porosity for PS/Si samples while increases for TiO2/PS/Si samples in both deposition methods. The reason could be due to filling pores by TiO2 nanoparticles and reduction of resistivity on PS surface. Also, our result showed that transient current increases highly for samples which were deposited by electron beam gun with respect to spin coating. The reason could be that in spin coating method TiO2 sol with high viscosity was used and causes that TiO2 nanoparticles cannot easily penetrate into PS pores. But in electron beam gun method TiO2 nanoparticles reaches to PS surface as a few atoms and can easily penetrate into PS pores. Ideality factor of our samples reduces after TiO2 deposition. Also, ideality factor of samples which were deposited by electron beam gun decreases with respect to spin coating, since transient current and I- V curve slop increase in electron beam gun.

  3. A 3.4-mm beam diameter system for retinal imaging with OCT and adaptive optics

    Science.gov (United States)

    Reddikumar, Maddipatla; Cense, Barry

    2017-04-01

    We present an adaptive-optics optical coherence tomography (AO-OCT) system with 3.4-mm beam diameter. A deformable mirror is used for the correction of two radial Zernike orders (defocus, vertical and oblique astigmatism). The aberrations are corrected sequentially with a Shack-Hartmann wave-front sensor and the deformable mirror. This system fills a gap between a standard clinical 1.2-mm beam diameter OCT system and a 6-mm beam diameter AO-OCT system. We also present 8° by 8° en face OCT images from a patient with macular degeneration. This system has a 25 cm by 50 cm footprint, which makes it considerably smaller to conventional 6-mm beam diameter AO-OCT system. Because of its larger field of view and smaller size, it is likely to be useful in the ophthalmic clinics for high-resolution imaging of the human eye retina.

  4. Beam test results of a 16 ps timing system based on ultra-fast silicon detectors

    Science.gov (United States)

    Cartiglia, N.; Staiano, A.; Sola, V.; Arcidiacono, R.; Cirio, R.; Cenna, F.; Ferrero, M.; Monaco, V.; Mulargia, R.; Obertino, M.; Ravera, F.; Sacchi, R.; Bellora, A.; Durando, S.; Mandurrino, M.; Minafra, N.; Fadeyev, V.; Freeman, P.; Galloway, Z.; Gkougkousis, E.; Grabas, H.; Gruey, B.; Labitan, C. A.; Losakul, R.; Luce, Z.; McKinney-Martinez, F.; Sadrozinski, H. F.-W.; Seiden, A.; Spencer, E.; Wilder, M.; Woods, N.; Zatserklyaniy, A.; Pellegrini, G.; Hidalgo, S.; Carulla, M.; Flores, D.; Merlos, A.; Quirion, D.; Cindro, V.; Kramberger, G.; Mandić, I.; Mikuž, M.; Zavrtanik, M.

    2017-04-01

    In this paper we report on the timing resolution obtained in a beam test with pions of 180 GeV/c momentum at CERN for the first production of 45 μm thick Ultra-Fast Silicon Detectors (UFSD). UFSD are based on the Low-Gain Avalanche Detector (LGAD) design, employing n-on-p silicon sensors with internal charge multiplication due to the presence of a thin, low-resistivity diffusion layer below the junction. The UFSD used in this test had a pad area of 1.7 mm2. The gain was measured to vary between 5 and 70 depending on the sensor bias voltage. The experimental setup included three UFSD and a fast trigger consisting of a quartz bar readout by a SiPM. The timing resolution was determined by doing Gaussian fits to the time-of-flight of the particles between one or more UFSD and the trigger counter. For a single UFSD the resolution was measured to be 34 ps for a bias voltage of 200 V, and 27 ps for a bias voltage of 230 V. For the combination of 3 UFSD the timing resolution was 20 ps for a bias voltage of 200 V, and 16 ps for a bias voltage of 230 V.

  5. Beam test results of a 16 ps timing system based on ultra-fast silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Cartiglia, N., E-mail: cartiglia@to.infn.it [INFN, Torino (Italy); Staiano, A.; Sola, V. [INFN, Torino (Italy); Arcidiacono, R. [INFN, Torino (Italy); Università del Piemonte Orientale (Italy); Cirio, R.; Cenna, F.; Ferrero, M.; Monaco, V.; Mulargia, R.; Obertino, M.; Ravera, F.; Sacchi, R. [INFN, Torino (Italy); Università di Torino, Torino (Italy); Bellora, A.; Durando, S. [Università di Torino, Torino (Italy); Mandurrino, M. [Politecnico di Torino, Torino (Italy); Minafra, N. [University of Kansas, KS (United States); Fadeyev, V.; Freeman, P.; Galloway, Z.; Gkougkousis, E. [SCIPP, University of California Santa Cruz, CA 95064 (United States); and others

    2017-04-01

    In this paper we report on the timing resolution obtained in a beam test with pions of 180 GeV/c momentum at CERN for the first production of 45 µm thick Ultra-Fast Silicon Detectors (UFSD). UFSD are based on the Low-Gain Avalanche Detector (LGAD) design, employing n-on-p silicon sensors with internal charge multiplication due to the presence of a thin, low-resistivity diffusion layer below the junction. The UFSD used in this test had a pad area of 1.7 mm{sup 2}. The gain was measured to vary between 5 and 70 depending on the sensor bias voltage. The experimental setup included three UFSD and a fast trigger consisting of a quartz bar readout by a SiPM. The timing resolution was determined by doing Gaussian fits to the time-of-flight of the particles between one or more UFSD and the trigger counter. For a single UFSD the resolution was measured to be 34 ps for a bias voltage of 200 V, and 27 ps for a bias voltage of 230 V. For the combination of 3 UFSD the timing resolution was 20 ps for a bias voltage of 200 V, and 16 ps for a bias voltage of 230 V.

  6. Measurement of the mean radial position of a lead ion beam in the CERN PS

    CERN Document Server

    Belleman, J; González, J; Johnston, S; Schulte, E C; Thivent, E

    1996-01-01

    The intensity of the lead ion beam in the PS, nominally 4×108 charges of Pb53+ per bunch, is too low for the closed orbit measurement system. However, for successful acceleration it is sufficient to know the mean radial position (MRP). A system was thus designed for simultaneous acquisition of revolution frequency and magnetic field. The frequency measurement uses a direct digital synthesiser (DDS), phase-locked to the beam signal from a special high-sensitivity pick-up. The magnetic field is obtained from the so-called B-train. From these two values, the MRP is calculated. The precision depends on the frequency measurement and on the accuracy of the value for the magnetic field. Furthermore, exact knowledge of the transition energy is essential. This paper describes the hardware and software developed for the MRP system, and discusses the issue of calibration, with a proton beam, of the B measurement.

  7. Economic feasibility of producing inside-out beams from small-diameter logs

    Science.gov (United States)

    David W. Patterson; Richard A. Kluender; James E. Granskog

    2002-01-01

    Previous work has shown that it is technically feasible to produce inside-out (ISO) beams by taking small-diameter (5 to 7 in.) logs, slabbing four sides, quartering the cant, and turning the quarters inside out and gluing them together. After drying, the beams were found to be straight, with no cracks, and of equal or better mechanical properties than solid sawn...

  8. Vertical septum magnets for distributing the beam to the 4 PS Booster rings

    CERN Multimedia

    Ordan, Julien Marius

    2017-01-01

    To facilitate H- injection from Linac4 to the PS Booster via the transfer line the BI.SMV10 (Booster Injection Septum Magnet Vertical) provides the vertical deflection of the 160 MeV H- beam to rings 1, 2 and 4 of the Booster. Currently this system is capable of deflecting 50 MeV protons and comprises an assembly of ferrite type magnets in an “omega” section vacuum tank (see fig. 1). The current system shall be replaced with a UHV compatible vacuum chamber incorporating 3 sets of double septum magnets, pulsed from 3 individual power supplies via transformers with 12:1 ratio.

  9. The Beam Profile Monitoring System for the IRRAD Proton Facility at the CERN PS East Area

    CERN Document Server

    Gkotse, Blerina; Matli, Emanuele; Ravotti, Federico; Gan, Kock Kiam; Kagan, Harris; Smith, Shane; Warner, Joseph

    2016-01-01

    In High Energy Physics (HEP) experiments, devices are frequently required to withstand a certain radiation level. As a result, detectors and electronics must be irradiated to determine their level of radiation tolerance. To perform these irradiations, CERN built a new irradiation facility in the East Area at the Proton Synchrotron (PS) accelerator. At this facility, named IRRAD, a high-intensity 24 GeV/c proton beam is used. During irradiation, it is necessary to monitor the intensity and the transverse profile of the proton beam. The Beam Profile Monitor (BPM) for IRRAD uses 39-channel pixel detectors to monitor the beam position. These pixel detectors are constructed using thin foil copper pads positioned on a flex circuit. When protons pass through the copper pads, they induce a measurable current. To measure this current and determine the total flux of protons passing through the thin foil copper detectors, a new data acquisition system was designed as well as a new database and on-line display system. In...

  10. Beam tests of MedAustron RF-jump at CERN’s PS Booster

    CERN Document Server

    Angoletta, M E; Hancock, S; Dorda, U

    2013-01-01

    MedAustron is a centre for ion beam cancer therapy (protons and carbon ions) and non-clinical research currently under construction in Wiener-Neustadt (Austria). MedAustron’s synchrotron Low-Level RF (LLRF) system is being developed in collaboration with CERN’s RF group. As part of the preparation of the beam for the betatron-core driven, horizontal third order slow resonant extraction, an RF-jump to the unstable phase must be executed which creates a uniform momentum spread of fixed width. A conceptual feasibility study of this RF-gymnastic was carried out during the 2012 run at CERN’s PS Booster (PSB). This consisted of several machine development sessions where the beam in PSB ring 4 was accelerated via a prototype Digital LLRF (DLLRF) system and a jump to the unstable phase and back was carried out in a controlled way. The aim of the study was to define the beam control features required to carry out this RF gymnastic and if possible to validate their implementation. This note describes the MedAu...

  11. Machine development studies for PSB extraction at 160 MeV and PSB to PS beam transfer

    CERN Document Server

    Forte, V; Bartmann, W; Borburgh, J; Ferrero Colomo, A; Damerau, H; Di Giovanni, G P; Coralejo Feliciano, L M; Fraser, M A; Gamba, D; Mikulec, B; Guerrero Ollacarizqueta, A; Serluca, M; Sermeus, L; Sterbini, G

    2017-01-01

    This paper collects the machine development (MD) activities for the beam transfer studies in 2016 concerning the PSB extraction and the PSB-to-PS transfer. Many topics are covered: from the 160 MeV extraction from the PSB, useful for the future commissioning activities after the connection with Linac4, to new methodologies for measuring the magnetic waveforms of kickers and dispersion reduction schemes at PS injection, which are of great interest for the LHC Injectors Upgrade (LIU) [1] project.

  12. A rule-based consultant for accelerator beam scheduling used in the CERN PS complex

    CERN Document Server

    Lewis, J; Varga, L Z

    1995-01-01

    The CERN PS accelerator complex consists of nine interacting accelerators which work together to produce particle beams for different end users, varying in particle type, energy, time structure, and geometry. The beam production schedule is time sliced, and depends on the current operational requirements, and dynamically on the accelerator status, so that production schedule changes occur in real time. Many potential schedules are not valid due to various system constraints and these constraints vary over time as new operational modes are introduced. In order to ensure that only valid schedules are given to the complex, an automated tool has been developed to indicate whether a potential schedule is valid or not. This presentation describes the method by which the validity of a beam schedule is determined and how this method was implemented using a rule-based approach based on SQL, avoiding the use of an expert system shell. Both the data to instantiate the rules and the rules themselves are kept in an Oracle...

  13. A single axis electrostatic beam deflection system for a 5-cm diameter ion thruster

    Science.gov (United States)

    Lathem, W. C.

    1972-01-01

    A single-axis electrostatic beam deflection system has been tested on a 5-cm diameter mercury ion thruster at a thrust level of about 0.43 mlb (25 mA beam current at 1400 volts). The accelerator voltage was 500 volts. Beam deflection capability of plus or minus 10 deg was demonstrated. A life test of 1367 hours was run at the above conditions. Results of the test indicated that the system could possibly perform for upwards of 10,000 hours.

  14. MD at the PS: Beam Break-Up Instability Near Transition

    CERN Document Server

    Kornilov, V; Gilardoni, S; Freyermuth, P

    2013-01-01

    Machine study experiments have been performed at the CERN PS during the week of June 18th, 2012, with the objective to continue the investigations of the fast (below ms) transverse high-frequency (0.7GHz) instability near transition, without $γ_t$ jump. Special attention is paid to the instability time- and space structure. The role of Landau damping is confirmed on the instability appearance time in the cycle, and on the intensity thresholds for different rf voltage. Other damping mechanisms, as the synchrotron motion, and the ratio between the bunch length and the perturbation wave length, are studied. The bunch parameter measurements demonstrate that the bunches are in the regime of strong space-charge regarding bunch dynamics, but the transverse emittance variations indicate that the space-charge effect does not affect the instability thresholds. Stability enhancement due to octupole magnets is measured for different beam parameters.

  15. A Large Diameter Entrance Window for the LHC Beam Dump Line

    CERN Document Server

    Presland, Andrew; Jiménez, J M; Ramos, D; Veness, Raymond

    2005-01-01

    The graphite LHC beam dump block TDE has to absorb the full LHC beam intensity at 7 TeV. The TDE vessel will be filled with inert gas at atmospheric pressure, and requires a large diameter entrance window for vacuum separation from the beam dumping transfer line. The swept LHC beam must traverse this window without damage for regular operation of the beam dump dilution system. For dilution failures, the entrance window must survive most of the accident cases, and must not fail catastrophically in the event of damage. The conceptual design of the entrance window is presented, together with the load conditions and performance criteria. The FLUKA energy deposition simulations and ANSYS stress calculations are described, and the results discussed.

  16. Measurement of therapeutic photon beams-induced Cerenkov radiation generated in PMMA- and PS-based plastic optical fibers

    Science.gov (United States)

    Lee, Bongsoo; Shin, Sang Hun; Yoo, Wook Jae; Jang, Kyoung Won

    2016-10-01

    In this study, we characterized Cerenkov radiation generated in polystyrene (PS)- and polymethyl methacrylate (PMMA)-based plastic optical fibers (POFs) to select an adequate optical fiber for producing Cerenkov radiation. To determine the relationship between the absorbed dose and the intensity of Cerenkov radiation, we calculated the energy depositions of photon beams and fluxes of electrons inducing Cerenkov radiation using the Monte Carlo N-Particle eXtended code. Also, intensities of Cerenkov radiation generated in PS- and PMMA-based POFs were measured as functions of dose rate and monitor unit. At last, therapeutic photon beams-induced Cerenkov radiation in PS- and PMMA-based POFs was measured according to depths of solid water phantom.

  17. Study of the beam-cavity interaction in the CERN PS 10 MHz cavities and investigation of hardware solutions to reduce beam loading

    CERN Document Server

    AUTHOR|(CDS)2086984; Palumbo, Luigi

    In the Proton Synchrotron (PS), where the LHC protons longitudinal structure (bunch spacing) is determined as the result of a sophisticated series of Radio Frequency (RF) gymnastics, collective effects were identified as a major limitation to the achievable beam current delivered to the LHC. Dedicated machine development studies pointed out the RF cavities to be one of the major source of instability in the PS. In particular, the 10 MHz RF system, responsible for beam acceleration, was identified as the most probable impedance source in the machine. The cavity impedance limits the circulating intensity in the accelerator since the beam-induced voltage could trigger longitudinal instabilities causing beam losses. For this reason the cavity impedance seen by the beam must be kept as low as possible. In the framework of the LHC Injector Upgrade (LIU) project, the present PS 10 MHz RF system requires an upgrade, in order to reach higher beam intensities and to reduce beam loading. This thesis focuses on the impro...

  18. Grid-translation beam deflection systems for 5-cm and 30-cm diameter Kaufman thrusters

    Science.gov (United States)

    Lathem, W. C.

    1972-01-01

    A 5-cm grid translation mechanism has been developed capable of 10 deg beam deflection. A 2026-hour endurance test was run at a preset 10 deg deflection angle and an extrapolated lifetime of better than 10,000 hours obtained. Response time data for grid translation are presented. Preliminary results for a 30-cm diameter system are given and results of a theoretical analysis of a dished grid system are discussed.

  19. Beam spot diameter of the near-field scanning electron microscopy.

    Science.gov (United States)

    Kyritsakis, A; Xanthakis, J P

    2013-02-01

    We have examined the beam spot diameter at the anode of the scanning electron microscopy (SEM) in the near-field mode as a function of the anode-tip distance d. The detector lateral resolution of this type of microscopy is approximately equal to this spot diameter. For our calculations we have simulated the apex region of the tip with an ellipsoid of revolution of radii R₁ and R₂ with R₁>R₂ as suggested by TEM images of the realistic tips. We have then solved the Laplace equation to obtain the electrostatic potential and to this we have added a spherical image potential. The calculated electrostatic field is highly asymmetric, being strong along the tip-axis and weakening quickly towards the sides. When a 3-dimensional WKB approximation is used to calculate the electron paths corresponding to such a potential, the latter are shown to bend significantly towards the vertical (tip-axis) direction producing a beam narrowing effect very similar to the beam narrowing effect we discovered for the traditional SEM case. When the values of R₁, R₂ are chosen from fittings to the TEM images of the tips used in the experiments, the beam spot diameter W at the anode (d=25 nm) varies from 12.5 nm to 9 nm depending on the fitted R₁, R₂. These values of W are considerably smaller than previously predicted by calculating solid angles of emission from spherical surfaces (41 nm) but also much closer to the detector lateral resolution (6-7 nm) obtained from differentiating the experimental current step. This trend continued at all other d examined. Furthermore the beam width W was found to decrease quickly with increasing sharpness S=R₁/R₂ of the tip and then saturate. W is also decreasing with decreasing R₁, R₂ with S kept constant. We deduce that the sharpness of the tip is important not only for creating high extraction fields but also for guaranteeing a very small beam spot diameter. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. New Shaving Scheme for Low-Intensity Beams in the CERN PS Booster and Feasibility at 160 MeV

    OpenAIRE

    Kowalska, Magdalena; Benedetto, Elena; Forte, Vincenzo; Mikulec, Bettina; Rumolo, Giovanni

    2015-01-01

    The PS Booster is the first synchrotron in the CERN proton accelerator chain, serving all downstream machines. As part of the LHC Injector Upgrade Project, the PSB injection energy will increase from 50 MeV to 160 MeV and a new H⁻ charge-exchange injection scheme will be implemented. Beam losses are a concern due to the increased injection energy, and mitigation scenarios are under investigation. On the other hand it is desirable for low-intensity beams to have the possibility to precisely ta...

  1. Large diameter dual-axis MEMS-based mirror for laser beam steering

    Science.gov (United States)

    Ilias, S.; Picard, F.; Le Foulgoc, K.; Osouf, J.; Larouche, C.; Caron, J.-S.; Topart, P.; Garcia Blanco, S.; Vincent, D.; Lepage, J. F.; Gilbert, B.

    2011-03-01

    The main goals of this work is the development of a large dual-axis MEMS mirror, ~3mm in diameter, capable of steering a laser beam within an angular cone of 60°. The targeted application involves the control of a laser beam with a particular interest for the resulting far field beam direction and profile. Finite element simulations using ANSYS modeling program were conducted to optimize the mirror design and determine the main characteristics of the mirror. The voltage required to tilt the mirror by 15° around each of the two axes was evaluated to be in the range of 700 V. The construction of this device is based on high precision structural dies assembly which relies on innovative developments in the fields of selective electroplating, deep reactive ion etching (DRIE) and thermocompression flip-chip bonding. The fabrication process involved the microassembly of 4 mirror parts, i.e. address electrodes, thick pedestal, gimbals structure and mirror plate. Single crystal silicon was used as material for the fabrication of the thick pedestal and mirror plate which provided the required large mirror-electrode gap and a high quality mirror with high flatness and low roughness. Soldering based on SnAu was considered for the microassembly of the thick pedestal to the address electrodes die, while Au-Au thermocompression bonding was considered to achieve the assembly of gimbals and mirror. The gimbals were supported by a polyimide sacrificial film to avoid damaging the hinges during mirror plate assembly.

  2. Numerical simulation of the processes of small-diameter high-current electron beam shaping and injection

    CERN Document Server

    Gordeev, V S; Myskov, G A

    2001-01-01

    With the aid of BEAM 25 program there was carried out the numerical simulation of the non-stationary process of shaping a small-diameter (<= 20mm) high-current hollow electron beam in a diode with magnetic insulation,as well as of the process of beam injection into the accelerating LIA track. The diode configuration for the purpose of eliminating the leakage of electron flux to the anode surface was update. Presented are the results of calculation of the injected beam characteristics (amplitude-time parameters of a current pulse, space-angle distributions of electrons etc.) depending on diode geometric parameters.

  3. Evolution of High Intensity Beams in the CERN PS Booster after H⁻ Injection and Phase Space Painting

    CERN Document Server

    Cieslak-Kowalska, Magdalena; Benedetto, Elena; Bracco, Chiara

    2016-01-01

    With the LHC Injector Upgrade (LIU) project, the injection energy of PS Booster (PSB) ' first circular accelerator in the LHC injector chain ' will be raised from 50 MeV to 160 MeV and the present multiturn injection will be upgraded to H⁻ injection with transverse and longitudinal painting. In the scope of this project, it is planned to double the beam intensities, profiting from the fact that the βγ2 factor will be two times larger (0.35 at 50 MeV and 0.71 at 160 MeV), so the resulting tune spread driven by a direct space charge should remain similar. This paper describes the feasibility to double the intensity of high intensity and large emittance beams, looking into the evolution under space charge and taking into account losses constrains in the ring and in the extraction lines.

  4. PS internal target area : three secondary beams heading towards the South Hall

    CERN Multimedia

    CERN PhotoLab

    1962-01-01

    The start of some of the secondary particle beams produced by the 28 GeV proton synchrotron. On the left, shielding bricks form a collimator; to their right are vacuum pipes, passing through guiding lenses and magnets, for beams of charged particles. (See also photo No 4878).

  5. Design of Air-Cooled Beam Dump for Extraction Line of PS Booster

    CERN Document Server

    Perillo-Marcone, A; Venturi, V; Antonakakis, T; Vlachoudis, V; Nowak, E; Mason, G; Battistin, M; Czapski, M; Sgobba, S

    2013-01-01

    A new beam dump has been designed, which withstands the future proton beam extracted from the Proton Syncrotron Booster (PSB) at CERN, consisting of up to 1E14 protons per pulse at 2 GeV after its upgrade in 2018/2019. In order to be able to efficiently release the deposited heat, the new dump will be made out of a single cylindrical block of a copper alloy and cooled by forced ventilation. In order to determine the energy density distribution deposited by the beam in the dump, Monte Carlo simulations were performed using FLUKA, and thermomechanical analyses carried out by importing the energy density into Ansys. In addition, CFD simulations of the airflow were carried out in order to accurately estimate the heat transfer convection coefficient on the surface of the dump. This paper describes the design process and highlights the constraints of integrating a new dump for increased beam power into the existing facility.

  6. A 5000-hour test of a grid-translation beam-deflection system for a 5-cm diameter Kaufman thruster

    Science.gov (United States)

    Lathem, W. C.

    1973-01-01

    A grid-translation type beam deflection system was tested on a 5-cm diameter mercury ion thruster for 5000 hours at a thrust level of about 0.36 mlb. During the first 2000 hours the beam was vectored 10 degrees in one direction. No erosion damage attributable to beam deflection was detected. Results indicate a possible lifetime of 15,000 to 20,000 hours. An optimized neutralizer position was used which eliminated the sputter erosion groove observed on the SERT 2 thrusters.

  7. Optical diagnostic suite (schlieren, interferometry, and grid image refractometry) on OMEGA EP using a 10-ps, 263-nm probe beam.

    Science.gov (United States)

    Froula, D H; Boni, R; Bedzyk, M; Craxton, R S; Ehrne, F; Ivancic, S; Jungquist, R; Shoup, M J; Theobald, W; Weiner, D; Kugland, N L; Rushford, M C

    2012-10-01

    A 10-ps, 263-nm (4ω) laser is being built to probe plasmas produced on the OMEGA EP [J. H. Kelly, L. J. Waxer, V. Bagnoud, I. A. Begishev, J. Bromage, B. E. Kruschwitz, T. E. Kessler, S. J. Loucks, D. N. Maywar, R. L. McCrory et al., J. Phys. IV France 133, 75-80 (2006)]. A suite of optical diagnostics (schlieren, interferometry, and grid image refractometry) has been designed to diagnose and characterize a wide variety of plasmas. Light scattered by the probe beam is collected by an f/4 catadioptric telescope and a transport system is designed to image with a near-diffraction-limited resolution (~1 - μm full width at half maximum) over a 5-mm field of view to a diagnostic table. The transport system provides a contrast greater than 1 : 10(4) with respect to all wavelengths outside of the 263 ± 2 nm measurement range.

  8. Laser beam measurement of abdominal sagittal diameter in obese children: a validation study.

    Science.gov (United States)

    Flodmark, C E; Shen, W; Punyanitya, M; Leander, P; Lanke, J; Pietrobelli, A

    2013-04-01

    Sagittal diameter (SAD) has been reported to correlate to visceral fat and cardiovascular risk factors. SAD is measured with the individual lying down, halfway between the lower rib margin and the iliac crest; it represents the mid-height of the abdomen. The aim of this study was to validate SAD measured using a recently-developed laser beam device (SAD(LDB) ) against SAD measured using MRI (SAD(MRI)). Of 48 obese children (25 boys, 23 girls) aged 9-11 years on the waiting list for obesity treatment, 34 agreed to a baseline measurement, which was followed by repeated measurements 6 and 12 months later in 31 and 22 children respectively. MRI was used to examine SAD(MRI) at 5 cm above (SAD(MRI,cra) ) and below (SAD(MRI,cau)) the mid plane of the L4-5 intervertebral disc. Each of the differences SAD(LBD) - SAD(MRI, cau) and SAD(LBD) - SAD(MRI,cra) was subjected to a repeated-measurements ANOVA; the visit did not have a statistically significant effect in either case (p = 0.19 and p = 0.72, respectively). The difference SAD(LBD) - SAD(MRI, cau) was 1.50 on average (p SAD(LBD) -SAD(MRI, cra) was 1.26 (p SAD(MRI) from SAD(LDB) can be performed in different ways: by means of linear regression or by means of an additive correction. Thus, this laser device can be used instead of MRI to estimate SAD by using a simple correction. © 2012 The Authors. Pediatric Obesity © 2012 International Association for the Study of Obesity.

  9. Beam diameter thresholds as applying light depolarization for effective submicron and micron root mean square roughness evaluation.

    Science.gov (United States)

    Liu, Linsheng; Nonaka, Kazuhiro

    2017-09-01

    To further study the microscopic mechanism and beam diameter effect during light depolarization (LDP), we developed a compact laser instrument (λ=632.8  nm) with an adjustable beam diameter of ≥18  μm (approximately 28λ). Six nickel plate samples with rms roughness, Rq, of 42 nm to 2.3 μm (i.e., 0.067-3.7λ) fabricated by the fine-honing method are examined. To analyze the beam diameter effect as applying LDP for submicron and micron Rq evaluation, the cross-sectional beam-spot size (BSS) is adjusted from 20 μm to 650 μm during off-specular inspections. The results of BSS ≤40  μm (i.e., 60λ) have a 10-nm-level Rq sensitivity, while those of BSS ≥140  μm (220λ) have about a 100 times weaker sensitivity. It means that BSS of 60λ and 220λ should have instructional significance as applying LDP for precision levels of 10 nm and 1 μm surface roughness analyses, respectively. In addition, since the instrument is simple, portable, stable, and low-cost, it has great potential for both LDP analyses and practical online roughness testing.

  10. Feasibility Study of the PS Injection for 2 GeV LIU Beams with an Upgraded KFA-45 Injection Kicker System Operating in Short Circuit Mode

    CERN Document Server

    Kramer, Thomas; Borburgh, Jan; Ducimetière, Laurent; Feliciano, Luis; Ferrero Colomo, Alvaro; Goddard, Brennan; Sermeus, Luc

    2016-01-01

    Under the scope of the LIU project the CERN PS Booster to PS beam transfer will be modified to match the requirements for the future 2 GeV beams. This paper describes the evaluation of the proposed upgrade of the PS injection kicker. Different schemes of an injection for LIU beams into the PS have been outlined in the past already under the aspect of individual transfer kicker rise and fall time performances. Homogeneous rise and fall time requirements in the whole PSB to PS transfer chain have been established which allowed to consider an upgrade option of the present injection kicker system operated in short circuit mode. The challenging pulse quality constraints require an improvement of the flat top and post pulse ripples. Both operation modes, terminated and short circuit mode are analysed and analogue circuit simulations for the present and upgraded system are outlined. Recent measurements on the installed kickers are presented and analysed together with the simulation data. First measurements verifying...

  11. The Proton Beams for the New Time-of-Flight Neutron Facility at the CERN-PS

    CERN Document Server

    Cappi, R; Métral, G

    2000-01-01

    The experimental determination of neutron cross sections in fission and capture reactions as a function of the neutron energy is of primary importance in nuclear physics. Recent developments at CERN and elsewhere have shown that many fields of research and development, such as the design of Accelerator-Driven Systems (ADS) for nuclear waste incineration, nuclear astrophysics, fundamental nuclear physics, dosimetry for radiological protection and therapy, would benefit from a better knowledge of neutron cross sections. A neutron facility at the CERN-PS has been proposed with the aim of carrying out a systematic and high resolution study of neutron cross sections through Time-Of-Flight (n-TOF) measurement. The facility requires a high intensity proton beam (about 0.7x1013 particles/bunch) distributed in a short bunch (about 25 ns total length) to produce the neutrons by means of a spallation process in a lead target. To achieve these characteristics, a number of complex beam gymnastics have to be performed. All...

  12. Production of slow positron beam with small diameter using electron linac in Osaka University

    Energy Technology Data Exchange (ETDEWEB)

    Honda, Yoshihide; Sawada, Junichi; Yamada, Masaki; Maekawa, Masaki; Okuda, Shuichi; Yoshida, Yoichi; Isoyama, Goro; Tagawa, Seiichi [Osaka Univ., Ibaraki (Japan). Inst. of Scientific and Industrial Research; Yamamoto, Takayoshi

    1997-03-01

    A slow positron facility using an electron linac was designed and constructed. The specifications were mainly decided by numerical calculations. The slow positrons are transported along magnetic field line. The cross sectional size of slow positron beam is 1-2cm and the maximum conversion rate from electron to positron is about 1.5 x 10{sup -6}. This value is about 1/4 of ideal case in our system. Extraction of slow positron beam from magnetic field region was made and preliminary brightness enhancement experiment was also performed. (author)

  13. Physical aspects of dynamic stereotactic radiosurgery with very small photon beams (1.5 and 3 mm in diameter).

    Science.gov (United States)

    Paskalev, Kamen A; Seuntjens, Jan P; Patrocinio, Horacio J; Podgorsak, Ervin B

    2003-02-01

    Stereotactic radiosurgery is often used for treating functional disorders. For some of these disorders, the size of the target can be on the order of a millimeter and the radiation dose required for treatment on the order of 80 Gy. The very small radiation field and high prescribed dose present a difficult challenge in beam calibration, dose distribution calculation, and dose delivery. In this work the dose distribution for dynamic stereotactic radiosurgery, carried out with 1.5 and 3 mm circular fields, was studied. A 10 MV beam from a Clinac-18 linac (Varian, Palo Alto, CA) was used as the radiation source. The BEAM/EGS4 Monte Carlo code was used to model the treatment head of the machine along with the small-field collimators. The models were validated with the EGSnrc code, first through a calculation of percent depth doses (PDD) and dose profiles in a water phantom for the two small stationary circular beams and then through a comparison of the calculated with measured PDD and profile data. The three-dimensional (3-D) dose distributions for the dynamic rotation with the two small radiosurgical fields were calculated in a spherical water phantom using a modified version of the fast XVMC Monte Carlo code and the validated models of the machine. The dose distributions in a horizontal plane at the isocenter of the linac were measured with low-speed radiographic film. The maximum sizes of the Monte Carlo-calculated 50% isodose surfaces in this horizontal plane were 2.3 mm for the 1.5 mm diameter beam and 3.8 mm for the 3 mm diameter beam. The maximum discrepancies between the 50% isodose surface on the film and the 50% Monte Carlo-calculated isodose surfaces were 0.3 mm for both the 1.5 and 3 mm beams. In addition, the displacement of the delivered dose distributions with respect to the laser-defined isocenter of the machine was studied. The results showed that dynamic radiosurgery with very small beams has a potential for clinical use.

  14. CERN News: Slow ejection efficiency at the PS; Vacuum tests on the ISR; Fire in the neutrino beam-line; Prototype r.f . cavity for the Booster; Crane-bridge in ISR experimental hall; Modifications to the r.f . system at the PS

    CERN Multimedia

    1969-01-01

    CERN News: Slow ejection efficiency at the PS; Vacuum tests on the ISR; Fire in the neutrino beam-line; Prototype r.f . cavity for the Booster; Crane-bridge in ISR experimental hall; Modifications to the r.f . system at the PS

  15. Accessory mental foramina: prevalence, position and diameter assessed by cone-beam computed tomography and digital panoramic radiographs.

    Science.gov (United States)

    Imada, Thaís Sumie Nozu; Fernandes, Luciana Maria Paes da Silva Ramos; Centurion, Bruna Stuchi; de Oliveira-Santos, Christiano; Honório, Heitor Marques; Rubira-Bullen, Izabel Regina Fischer

    2014-02-01

    To investigate the presentation of accessory mental foramina (AMF) on cone-beam computed tomography (CBCT) and digital panoramic examinations (PAN). Imaging examinations (i.e., CBCT and PAN) of 100 patients (200 hemi-mandibles) were assessed. AMF prevalence, diameter, and location related to adjacent teeth and to the mental foramen (MF) were analyzed. On CBCT images, the AMF was observed in 3% of the patients: two unilateral cases and one bilateral case, with mean diameter of 0.93 mm (±0.3); no AMF was identified on PAN. Most AMF were located between the premolars, either superiorly (two cases) or mesially (two cases) to the MF. The mean horizontal distance to the corresponding MF was 2.3 mm (±1.0) and the mean vertical distance was 4.0 mm (±0.7). The results of this study suggest that CBCT is an effective tool for presurgical tridimensional assessment of the neurovascular structures, such as MF and its variations; On the other hand, PAN examinations were not able to show the AMF cases assessed on CBCT. © 2012 John Wiley & Sons A/S.

  16. Detailed magnetic model simulations of the H- injection chicane magnets for the CERN PS Booster Upgrade, including eddy currents and influence on beam dynamics

    CERN Document Server

    Benedetto, E; Borburgh, J; Carli, C; Martini, M; Forte, V

    2014-01-01

    The CERN PS Booster will be upgraded with an H- injection system. The chicanemagnets for the injection bump ramp-down in 5 ms and generate eddy currents in the inconel vacuum chamber which perturb the homogeneity of the magnetic field. The multipolar field components are extracted from 3D OPERA simulations and are included in the lattice model. The -beating correction is computed all along the ramp and complete tracking simulations including space-charge are performed to evaluate the impact of these perturbations and correction on beam dynamics.

  17. PS injection area

    CERN Multimedia

    1974-01-01

    Looking against the direction of protons in the main ring (left): the beam coming from the linac 1 either goes to the booster (on the right) or is deflected towards the PS to be directly injected into section 26 (facing the camera). Also shown the start of the TT2 line, ejected from straight section 16 to go towards the ISR passing over the beam line from the linac. (see Photo Archive 7409009)

  18. Inside the PS tunnel

    CERN Multimedia

    1974-01-01

    Pre-start work is going on at the end of the PS long shut-down. The photo shows secondary beams drawn from an internal target (bottom) towards South Hall, behind the shielding wall (top) (see also photo 7409012X).

  19. PS auxiliary magnet

    CERN Multimedia

    CERN PhotoLab

    1974-01-01

    Units of the PS auxiliary magnet system. The picture shows how the new dipoles, used for vertical and horizontal high-energy beam manipulation, are split for installation and removal so that it is not necessary to break the accelerator vacuum. On the right, adjacent to the sector valve and the windings of the main magnet, is an octupole of the set.

  20. Determination of the Neutron Fluence, the Beam Characteristics and the Backgrounds at the CERN-PS TOF Facility

    CERN Multimedia

    Leal, L C; Kitis, G; Guber, K H; Quaranta, A; Koehler, P E

    2002-01-01

    In the scope of our programme we propose to start in July 2000 with measurements on elements of well known cross sections, in order to check the reliability of the whole experimental installation at the CERN-TOF facility. These initial exploratory measurements will provide the key-parameters required for the further experimentation at the CERN-TOF neutron beam. The neutron fluence and energy resolution will be determined as a function of the neutron kinetic energy by reproducing standard capture and fission cross sections. The measurements of capture cross sections on elements with specific cross section features will allow to us to disentangle the different components of backgrounds and estimate their level in the experimental area. The time-energy calibration will be determined and monitored with a set of monoenergetic filters as well as by the measurements of elements with resonance-dominated cross sections. Finally, in this initial phase the behaviour of several detectors scheduled in successive measureme...

  1. Design of a low-temperature plasma (LTP) probe with adjustable output temperature and variable beam diameter for the direct detection of organic molecules.

    Science.gov (United States)

    Martínez-Jarquín, Sandra; Winkler, Robert

    2013-03-15

    The direct detection of organic molecules by mass spectrometry requires ionization methods which are compatible with ambient conditions. A relatively new strategy is the use of a free low-temperature plasma beam for ionization. The objective is to design a safe and adjustable plasma beam to enable optimal ionization and desorption parameters for specific molecules. A plasma probe based on a dielectric barrier discharge was designed, where the plasma is guided through an internal second tube. This setup permits different beam diameter settings and the control of the plasma temperature. The ionization and desorption of pure organic compounds, as well as their direct detection from roasted coffee beans, were tested. The presented plasma probe provides improved safety with respect to arcing, ozone generation and electric shock, compared with conventional designs. The functionality of previously reported devices is expanded. A defined plasma diameter can be set by choosing the appropriate insert, while the input voltage controls the plasma temperature. The variation of measurement parameters enables the optimized direct detection of target compounds from roasted coffee beans, such as caffeine, guaiacol and vanillin. The presented low-temperature plasma probe allows the fine-tuning of ionization and desorption parameters, according to the target molecules. Possible applications include: (1) The ambient ionization and desorption of organic compounds with different volatility and (2) The direct analysis of food products such as roasted coffee beans. Copyright © 2013 John Wiley & Sons, Ltd.

  2. Porcine skin damage thresholds for 0.6 to 9.5 cm beam diameters from 1070-nm continuous-wave infrared laser radiation.

    Science.gov (United States)

    Vincelette, Rebecca; Noojin, Gary D; Harbert, Corey A; Schuster, Kurt J; Shingledecker, Aurora D; Stolarski, Dave; Kumru, Semih S; Oliver, Jeffrey W

    2014-03-01

    There is an increasing use of high-power fiber lasers in manufacturing and telecommunications industries operating in the infrared spectrum between 1000 and 2000 nm, which are advertised to provide as much as 10 kW continuous output power at 1070 nm. Safety standards have traditionally been based on experimental and modeling investigations with scant data available for these wavelengths. A series of studies using 1070-nm infrared lasers to determine the minimum visible lesion damage thresholds in skin using the Yucatan miniature pig (Sus scrofa domestica) for a range of beam diameters (0.6, 1.1, 1.9, 2.4, 4.7, and 9.5 cm) and a range of exposure durations (10 ms to 10 s) is presented. Experimental peak temperatures associated with each damage threshold were measured using thermal imaging. Peak temperatures at damage threshold for the 10-s exposures were ∼10°C lower than those at shorter exposures. The lowest and highest experimental minimum visible lesion damage thresholds were found to have peak radiant exposures of 19 and 432  J/cm2 for the beam diameter-exposure duration pairs of 2.4 cm, 25 ms and 0.6 cm, 10 s, respectively. Thresholds for beam diameters >2.5  cm had a weak to no effect on threshold radiant exposure levels for exposure times ≤0.25  s, but may have a larger effect on thresholds for exposures ≥10  s.

  3. Ordering of self-assembled 5-nm-diameter poly(dimethylsiloxane) nanodots with sub-10 nm pitch using ultra-narrow electron-beam-drawn guide lines and three-dimensional control

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hui, E-mail: t10802275@gunma-u.ac.jp [Human Resources Cultivation Center, Gunma University, 1-5-1 Tenjin, Kiryu, Gunma 376-8515 (Japan); Hosaka, Sumio; Yin, You [Division of Electronics and Informatics, Faculty of Science and Technology, Gunma University, 1-5-1 Tenjin, Kiryu, Gunma 376-8515 (Japan)

    2014-03-03

    We demonstrate the possibility of forming long-range ordered self-assembled arrays of 5-nm-diameter nanodots with pitch of 10 × 7.5 nm{sup 2} using guide line templates and low molecular weight (MW) (4700–1200 g/mol) poly(styrene)-poly(dimethylsiloxane) (PS-PDMS) for application in ultrahigh density patterned magnetic recording media. We propose a three-dimensional control which involves control of the height of the guide lines, the thickness of the PS-PDMS films, and the gap between the guide lines in order to produce 5-nm-diameter, sub-10 nm pitched nanodots with long-range order along the guide lines. Adopting a 13-nm-thick PS-PDMS film and 14-nm-high resist guide lines, the 5-nm-diameter and 10 × 7.5 nm{sup 2}-pitched self-assembled nanodots were ordered in 4–7 dot arrays with long-range order. The experimental results demonstrate that the method is suitable for the production of patterned media with magnetic recording densities of 8.6 Tbit/in.{sup 2} using low MW PS-PDMS and slim guide lines.

  4. The PS Booster hits 40

    CERN Multimedia

    Joannah Caborn Wengler

    2012-01-01

    Many accelerators’ "round" birthdays are being celebrated at CERN these days – the PS turned 50 in 2009, the SPS was 35 in 2011, and this year it's the turn of the PS Booster to mark its 40th anniversary. Originally designed to accelerate 1013 protons to 800 MeV, it has far exceeded its initial design performance over the years.   The PS Booster in the 1970s. Imagine the scene: a group of accelerator physicists staring expectantly at a monitor, when suddenly a shout of joy goes up as a signal flickers across the screen. Does that sound familiar? Well, turn the clock back 40 years (longer hair, wider trouser legs) and you have the situation at the PS Booster on 26 May 1972. On that day, beam was injected into the Booster for the first time. “It was a real buzz,” says Heribert Koziol, then Chairman of the Running-in Committee. “We were very happy – and also a little relieved – when the beam finally...

  5. Replacing the Beam Dump at the Booster

    CERN Multimedia

    2013-01-01

    The PS Booster Dump, designed in the 1960’s to cope with beam energies in the order of 800 MeV, has been dismantled and replaced with a new one, capable of withstanding the 2 GeV beam provided by the upcoming LINAC4 at CERN. This video shows the installation of that new dump core inside a one-metre diameter cavity, surrounded by five shielding rings made of concrete and steel. It is the culmination of months of preparation, an interdisciplinary work involving several teams from the Engineering, Beams and Technology Departments, as well as the collaboration and supervision of radio-protection experts.

  6. PAN/PS elctrospun fibers for oil spill cleanup

    Science.gov (United States)

    Ying, Qiao; Lili, Zhao; Haixiang, Sun; Peng, Li

    2014-08-01

    A high-capacity oil sorbent was fabricated by electrospinning using PS/PAN blend. Morphology, contact angle and oil adsorption of PAN/PS fiber and PP nonwoven fabric were studied. It was found that the PAN/PS fiber had a smaller diameter than PP, and the maximum sorption capacities of the PAN/PS sorbent for pump oil, peanut oil, diesel, and gasoline were 194.85, 131.7, 66.75, and 43.38 g/g, which were far higher than those of PP. The sorbent PS/PAN fiber showed a contact angle of water144.32° and diesel oil 0°. The sorption kinetics of PAN/PS and PP sorbent were also investigated. Compared with the commercial PP fabric, the PAN/PS fiber seems to have the ability to be used in oil-spill cleanup application.

  7. PS buildings : reinforced concrete structure for shielding "bridge" pillar

    CERN Multimedia

    CERN PhotoLab

    1956-01-01

    The PS ring traverses the region between the experimental halls South and North (buildings Nos 150 and 151) under massive bridge-shaped concrete beams. This pillar stands at the S-W end of the structure.

  8. Last PS magnet refurbished

    CERN Document Server

    2009-01-01

    PS Magnet Refurbishment Programme Completed. The 51st and final refurbished magnet was transported to the PS on Tuesday 3 February. The repair and consolidation work on the PS started back in 2003 when two magnets and a busbar connection were found to be faulty during routine high-voltage tests. The cause of the fault was a combination of age and radiation on electrical insulation. After further investigation the decision was taken to overhaul half of the PS’s 100 magnets to reduce the risk of a similar fault. As from 20 February the PS ring will start a five-week test programme to be ready for operation at the end of March.

  9. Physics at the AD/PS/SPS (1/4)

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    Lecture 1: The CERN injector complex and beams for non-LHC physics. The various machines and beam lines in the CERN injector complex are presented, from the linacs to the SPS. Special emphasis is given to the beam lines at the PS and SPS machines: AD, North and East Areas, nTOF and CNGS and HiRadMad as well as the ion beams. A short outlook is given to possible future upgrades and projects.

  10. A&T Sector Note on the PS transverse feedback

    CERN Document Server

    Coly, Marcel; Blas, Alfred; Sterbini, Guido; CERN. Geneva. ATS Department

    2017-01-01

    In a particle accelerator, several contributions can degrade the beam quality and particularly the beam transverse emittance. In this document we will describe a system used in the CERN Proton Synchrotron (PS) to cope with the injection steering errors and the transverse instabilities: the PS transverse feedback (PS TFB). As time progresses, this system is also being used for other purpose, to increase in a controlled way the beam transverse emittance and to excite the beam for the Multi-Turn-Extraction (MTE). In 2016, it has been successfully used on some operational beams to damp injection oscillations. This allowed to test the reliability of the system for its operational deployment. A piquet service is available in case of problem.

  11. PS Control Room

    CERN Multimedia

    CERN PhotoLab

    1963-01-01

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

  12. Measuring target for the PS Booster

    CERN Multimedia

    1971-01-01

    The measuring target for the PS Booster (originally 800 MeV, now 1.4 GeV). It measures the size of the beam by destroying all particles with amplitudes greater than the size of the fork, the position and width of which are adjustable. The plunging time is only 20 ms and the acceleration at the tip of the fork reaches 90 g. The servo-controlled linear motor is shown detached from the mechanism. See also 7602008.

  13. PS injection area

    CERN Multimedia

    1974-01-01

    To the right is the PS ring viewed along the direction of the protons. At the left the injection line coming from the 50 MeV Linac 1 (bottom) and going towards the 800 MeV booster, or deflected to the right to be injected directly into straight section 16. The drumlike element behind the (blue) dipole magnet is a 'debuncher' (a 200 MHz cavity). See photos 7409014X and 7409009.

  14. Delay-line cables for the fast bumpers in the PS.

    CERN Multimedia

    CERN PhotoLab

    1976-01-01

    For 'continuous transfer' to the SPS, the beam accelerated in the PS is shaved off over several turns, so as to form a continuous sequence of bunches several times the length of the PS circumference. Fast bumpers, powered in a 'staircase' way, displace the PS beam stepwise towards the ejection septum. Each step lasts 2.1 microsec and the cable drums in this picture contain some of the bumper delay-lines of altogether 10 km.

  15. Hybrid fs/ps CARS for Sooting and Particle-laden Flames [PowerPoint

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmeister, Kathryn N. Gabet; Guildenbecher, Daniel Robert; Kearney, Sean P.

    2016-01-01

    We report the application of ultrafast rotational coherent anti-Stokes Raman scattering (CARS) for temperature and relative oxygen concentration measurements in the plume emanating from a burning aluminized ammonium perchlorate propellant strand. Combustion of these metal-based propellants is a particularly hostile environment for laserbased diagnostics, with intense background luminosity, scattering and beam obstruction from hot metal particles that can be as large as several hundred microns in diameter. CARS spectra that were previously obtained using nanosecond pulsed lasers in an aluminumparticle- seeded flame are examined and are determined to be severely impacted by nonresonant background, presumably as a result of the plasma formed by particulateenhanced laser-induced breakdown. Introduction of fs/ps laser pulses enables CARS detection at reduced pulse energies, decreasing the likelihood of breakdown, while simultaneously providing time-gated elimination of any nonresonant background interference. Temperature probability densities and temperature/oxygen correlations were constructed from ensembles of several thousand single-laser-shot measurements from the fs/ps rotational CARS measurement volume positioned within 3 mm or less of the burning propellant surface. Preliminary results in canonical flames are presented using a hybrid fs/ps vibrational CARS system to demonstrate our progress towards acquiring vibrational CARS measurements for more accurate temperatures in the very high temperature propellant burns.

  16. Hybrid fs/ps CARS for Sooting and Particle-laden Flames

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmeister, Kathryn N. Gabet; Guildenbecher, Daniel Robert; Kearney, Sean P.

    2015-12-01

    We report the application of ultrafast rotational coherent anti-Stokes Raman scattering (CARS) for temperature and relative oxygen concentration measurements in the plume emanating from a burning aluminized ammonium perchlorate propellant strand. Combustion of these metal-based propellants is a particularly hostile environment for laserbased diagnostics, with intense background luminosity, scattering and beam obstruction from hot metal particles that can be as large as several hundred microns in diameter. CARS spectra that were previously obtained using nanosecond pulsed lasers in an aluminumparticle- seeded flame are examined and are determined to be severely impacted by nonresonant background, presumably as a result of the plasma formed by particulateenhanced laser-induced breakdown. Introduction of fs/ps laser pulses enables CARS detection at reduced pulse energies, decreasing the likelihood of breakdown, while simultaneously providing time-gated elimination of any nonresonant background interference. Temperature probability densities and temperature/oxygen correlations were constructed from ensembles of several thousand single-laser-shot measurements from the fs/ps rotational CARS measurement volume positioned within 3 mm or less of the burning propellant surface. Preliminary results in canonical flames are presented using a hybrid fs/ps vibrational CARS system to demonstrate our progress towards acquiring vibrational CARS measurements for more accurate temperatures in the very high temperature propellant burns.

  17. At PS170 (APPLE)

    CERN Multimedia

    CERN PhotoLab

    1983-01-01

    APPLE stands for Antiproton-Proton to Pair of LEptons (an acronym of the ancestor experiment PAPLEP), the PS170 experiment setup at LEAR to study e+e-pair production in antiproton-proton annihilation by Padova-(CEN) Saclay- Torino Collaboration. It consisted of a liquid hydrogen target surrounded by several layers of proportional chambers in the vertical field of a C-magnet (this photo), a gas Cerenkov counter, wire chambers, hodoscopes, and an electromagnetic calorimeter (see photo 8302539X, 8302540X). See also photo 8301539X for the setup assembly at an early stage.

  18. Beyond iPS!

    Directory of Open Access Journals (Sweden)

    Editorial

    2012-01-01

    Full Text Available It’s undoubtedly a jubilant moment for scientists and clinicians working in the stem cell arena as Prof. Gurdon and Prof. Shinya Yamanaka have been chosen for the Nobel Prize in Physiology & Medicine this year. The mystery of cell biology is something unfathomable and probably the work of this duo as well as the other scientists, who have put their hands on in- vitro de-differentiation have opened our eyes to a new window or a new paradigm in cell biology. The iPS invention has brought a lot of hope in terms of potential direct benefits to treat several diseases, which have no definite options at the moment. But, we envisage that several spin-offs could come out of this invention and one very significant spin-off finding recently witnessed is the finding by Prof. Masaharu Seno and his team of researchers at the Okayama University, Japan (Chen L, et al. 2012, PLoS ONE 7(4:e33544.doi:10.1371/journal.pone.0033544. According to Prof. Seno, mouse iPS cells (miPS when cultured in the conditioned medium derived from cancer cell lines, differentiate into cancer stem cells (CSCs. While differentiating into CSCs, they do retain the potential to develop endothelial progenitor cells. Several questions arise here: 1.Are these miPS derived CSCs really pluripotent, even if the terminal differentiation destined to specific phenotypes? 2.Shouldn’t the Cancer Stem Cells be termed as cancer progenitor cells, as till date they are considered to be producing only cancer cells but not pluripotent to yield other types of normal tissues? The spin-offs could be infinite as the process of differentiation and de-differentiation happening due to trillions of signals and pathways, most still remaining not-so-well understood. A special mention should be made to Prof. Shinya Yamanaka as he has several sterling qualities to be a role-model for budding scientists. Apart from his passion for science, which made him shift his career from orthopedics to a cell biologist, his

  19. The PS Booster Fast Wire Scanner

    CERN Document Server

    Burger, S; Priestnall, K; Raich, U

    2003-01-01

    The very tight emittance budget for LHC type beams makes precise emittance measurements in the injector complex a necessity. The PS machine uses 2 fast wire scanners per transverse plane for emittance measurement of the circulating beams. In order to ease comparison the same type of wire scanners have been newly installed in the upstream machine, the PS Booster, where each of the 4 rings is equipped with 2 wire scanners measuring the horizontal and vertical profiles. Those wire scanners use new and more modern control and readout electronics featuring dedicated intelligent motor movement controllers, which relieves the very stringent real time constraints due to the very high speed of 20m/s. In order to be able to measure primary beams at the very low injection energy of the Booster (50MeV) secondary emission currents from the wire can be measured as well as secondary particle flows at higher primary particle energies during and after acceleration. The solution adopted for the control of the devices is descri...

  20. Position pickup of the PS Booster

    CERN Multimedia

    CERN PhotoLab

    1975-01-01

    The beam position around the 4 rings of the PS Booster (originally 800 MeV, now 1.4 GeV), is measured with electrostatic pickups (PU). They consist of a ceramic cylinder forming part of the vacuum chamber, and, in order to save space, they are located inside the multipole lenses. The inside of the ceramic is coated with a metallic layer, into which the form of the electrodes was cut by computer-controlled micro-sandblasting. Each PU has a pair of horizontal and a pair of vertical electrodes, as well as a separate intensity-sensing circular electrode.

  1. Space charge studies in the PS

    CERN Document Server

    Asvesta, F; Damerau, H; Huschauer, A; Papaphilippou, Y; Serluca, M; Sterbini, G; Zisopoulos, P

    2017-01-01

    In this paper the results of Machine Development (MD)studies conducted at the CERN Proton Sychrotron (PS) arepresented. The main focus was the investigation of newworking points in an effort to characterize and potentiallyimprove the brightness for LHC-type beams in view of theLHC Injectors Upgrade (LIU). Various working points werecompared in terms of losses and emittance evolution. Sincespace charge and the resonances it excites are the main causefor emittance blow-up and losses, tunes close to excitedresonances were carefully studied. Mitigation techniques,such as bunch flattening using a double harmonic RF system,were also tested.

  2. Failure Diameter Resolution Study

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-12-19

    Previously the SURFplus reactive burn model was calibrated for the TATB based explosive PBX 9502. The calibration was based on fitting Pop plot data, the failure diameter and the limiting detonation speed, and curvature effect data for small curvature. The model failure diameter is determined utilizing 2-D simulations of an unconfined rate stick to find the minimum diameter for which a detonation wave propagates. Here we examine the effect of mesh resolution on an unconfined rate stick with a diameter (10mm) slightly greater than the measured failure diameter (8 to 9 mm).

  3. The new heart of the PS is beating strongly

    CERN Document Server

    Corinne Pralavorio

    2011-01-01

    The PS has resumed operation with a brand new electrical power system called POPS; this enormous system comprising power electronics and capacitors is crucial because if it broke down practically no particles would be able to circulate at CERN. As soon as it started, POPS passed all the tests with flying colours and is now pulsing at full power.   The new PS power system is made up of 6 containers, each with 60 tonnes of capacitors and 8 power converters. The date 11/02/11 will always be remembered with affection by the engineers in the Electrical Power Converters Group. At 11:11 in the morning (no joke), the first beams powered by the new system began to circulate in the PS. The cutely-named POPS (POwer for PS) took over from the old rotating machine that had been working since 1968. From now on it will be POPS that supplies the PS main magnets with the electrical pulses needed to accelerate the beams for the LHC and all CERN's other facilities. The system is crucial as the PS is one of the lyn...

  4. Longitudinal coupled-bunch instability studies in the PS

    CERN Document Server

    Damerau, H

    2017-01-01

    The main longitudinal limitation for LHC-type beams inthe PS are coupled-bunch instabilities. A dedicated proto-typefeedbacksystemusingaFinemetcavityasalongitudinalkicker has been installed. Extensive tests with beam havebeen performed to explore the intensity reach with this feed-back. The maximum intensity with nominal longitudinalemittance at PS extraction has been measured, as well as theemittance required to keep the beam longitudinally stableat the design intensity for the High-Luminosity LHC (HL-LHC). A higher-harmonic cavity is a complementary op-tion to extend the intensity reach beyond the capabilities ofthe coupled-bunch feedback. Preliminary machine develop-ment (MD) studies operating one20MHzor one40MHzRF system as a higher harmonic at the flat-top indicate thebeneficial effect on longitudinal beam stability

  5. Enhanced personal protection system for the PS

    CERN Multimedia

    Caroline Duc

    2013-01-01

    During the first long shutdown (LS1) a new safety system will be installed in the primary beam areas of the PS complex in order to bring the standard of personnel radiation protection at the PS into line with that of the LHC.   Pierre Ninin, deputy group leader of GS-ASE and responsible for the installation of the new PS complex safety system, in front of a new access control system. The LHC access control systems are state-of-the-art, whereas those of the injection chain accelerators were running the risk of becoming obsolete. For the past two years a project to upgrade the access and safety systems of the first links in the LHC accelerator chain has been underway to bring them into compliance with nuclear safety standards. These systems provide the personnel with automatic protection by limiting access to hazardous areas and by ensuring that nobody is present in the areas when the accelerator is in operation. By the end of 2013, the project teams will ha...

  6. SPS and PS Experiments Committee

    CERN Multimedia

    CERN. Geneva

    2004-01-01

    OPEN SESSION: 09:00 Status report of NA58 / COMPASS: A. Magnon 09:40 Status report of PS212 / DIRAC: L. Tausher 10:10 PS212 / DIRAC Addendum: L. Nemenov CLOSED SESSION on Tuesday, 27 April 2004 after the open session, Main Building, 6th floor conference room

  7. Multipole stack for the 4 rings of the PS Booster

    CERN Multimedia

    CERN PhotoLab

    1976-01-01

    The PS Booster (originally 800 MeV, now 1.4 GeV) saw first beam in 1972, routine operation began in 1973. The strive for ever higher intensities required the addition of multipoles. Manufacture of 8 stacks of multipoles was launched in 1974, for installation in 1976. For details, see 7511120X.

  8. Electrostatic septum for "Continuous Transfer" from PS to SPS

    CERN Multimedia

    CERN PhotoLab

    1982-01-01

    For "Continuous Transfer" to the SPS, the PS beam, after acceleration, is peeled off in 5 turns. To minimize losses, the magnetic septa are preceded by an electrostatic septum in straight section 31. We see the inner part of it, on a lab-bench. The first part consists of W-wires, the second part is a Mo-foil. The circulating beam passes through the opening, the ejected beam at the outside (above the wires, in this picture). This assembly is the anode-part, the cathode is not shown.

  9. Injection and transfer lines of the PS Booster

    CERN Multimedia

    Photographic Service

    1972-01-01

    In the foreground is the vacuum chamber for the 50 MeV proton beam coming from the Linac. The tank held by white frames houses the "Vertical Distributor", which deflects the Linac beam to the levels of the Booster's 4 superposed rings. After acceleration in the Booster, originally to 800 MeV, today to 1.4 GeV, the beams from the 4 rings are combined in the vertical plane and transfered to the 26 GeV PS. The "Recombination Line", intersecting the injection line, crosses the picture from left to right.

  10. Transfer line from the PSB to the PS (recombination)

    CERN Multimedia

    CERN PhotoLab

    1976-01-01

    After sequential ejection of 5 bunches from each of the 4 rings of the Booster (originally 800 MeV, now 1.4 GeV), the 4 batches are brought to the same vertical level, so as to form a string of 20 bunches, filling the circumference of the PS. This vertical "recombination" is performed in the transfer line, using vertical bending magnets, septa and kickers. Here we see the section where the beam from ring 4 (the top one) is brought down to the level of ring 3, and the beam from ring 1 up to the level of ring 2. Further downstream (to the right, outside this picture), level 2 is brought up to level 3, identical to that of the PS. After this original recombination scheme, other ways of combining the 4 beams, vertically and/or longitudinally, were developed and used in operation.

  11. 29 mm Diameter Test Target Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Olivas, Eric Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Naranjo, Angela Carol [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Romero, Frank Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-15

    The Northstar target for Mo99 production is made up of Mo100 disks in a stack separated by coolant gaps for helium flow. A number of targets have been tested at ANL for both production of Mo99 and for thermal-hydraulic performance. These have all been with a 12 mm diameter target, even while the production goals have increased the diameter to now 29 mm. A 29 mm diameter target has been designed that is consistent with the ANL beam capabilities and the capabilities of the helium circulation system currently in use at ANL. This target is designed for 500 μA at 35 MeV electrons. While the plant design calls for 42 MeV, the chosen design point is more favorable and higher power given the limits of the ANL accelerator. The intended beam spot size is 12 mm FWHM, but the thermal analysis presented herein conservatively assumed a 10 mm FWHM beam, which results in a 44% higher beam current density at beam center.

  12. Beam commission of the high intensity proton source developed at INFN-LNS for the European Spallation Source

    Science.gov (United States)

    Neri, L.; Celona, L.; Gammino, S.; Miraglia, A.; Leonardi, O.; Castro, G.; Torrisi, G.; Mascali, D.; Mazzaglia, M.; Allegra, L.; Amato, A.; Calabrese, G.; Caruso, A.; Chines, F.; Gallo, G.; Longhitano, A.; Manno, G.; Marletta, S.; Maugeri, A.; Passarello, S.; Pastore, G.; Seminara, A.; Spartà, A.; Vinciguerra, S.

    2017-07-01

    At the Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali del Sud (INFN-LNS) the beam commissioning of the high intensity Proton Source for the European Spallation Source (PS-ESS) started in November 2016. Beam stability at high current intensity is one of the most important parameter for the first steps of the ongoing commissioning. Promising results were obtained since the first source start with a 6 mm diameter extraction hole. The increase of the extraction hole to 8 mm allowed improving PS-ESS performances and obtaining the values required by the ESS accelerator. In this work, extracted beam current characteristics together with Doppler shift and emittance measurements are presented, as well as the description of the next phases before the installation at ESS in Lund.

  13. Diameter Perfect Lee Codes

    CERN Document Server

    Horak, Peter

    2011-01-01

    Lee codes have been intensively studied for more than 40 years. Interest in these codes has been triggered by the Golomb-Welch conjecture on the existence of perfect error-correcting Lee codes. In this paper we deal with the existence and enumeration of diameter perfect Lee codes. As main results we determine all q for which there exists a linear diameter-4 perfect Lee code of word length n over Z_{q}, and prove that for each n\\geq3 there are unaccountably many diameter-4 perfect Lee codes of word length n over Z. This is in a strict contrast with perfect error-correcting Lee codes of word length n over Z as there is a unique such code for n=3, and its is conjectured that this is always the case when 2n+1 is a prime. Diameter perfect Lee codes will be constructed by an algebraic construction that is based on a group homomorphism. This will allow us to design an efficient algorithm for their decoding.

  14. Characterization of crosslinked polystyrene(PS) beads in SBR matrix

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Yoon-Jong; Choe, Soonja [Inha Univ. (Korea, Republic of)

    1995-12-01

    Monodisperse sized crosslinked polystyrene(PS) beads were prepared by a reaction of semibatch emulsion polymerization with styrene monomer, divinylbenzene(DVB) crosslinking agent and potassium persulfate(K{sub 2}S{sub 2}O{sub 9}) initiator in the absence of emulsifier. The glass transition temperature(T{sub g}) and the mean diameter of the beads were increased from 100{degrees}C to 135{degrees}C and from 402 nm to 532 nm, respectively, for an incorporation of 2 to 10 mol% DVB. Crosslinking density was also linearly increased with DVB content. SEM microphotographs of SBR composite filled with various contents of PS beads revealed that PS beads are relatively well dispersed without changing the spherical shape of the beads in all range of compositions. In stress-strain analysis, elongation at break and tensile strength of SBR composite were increased with the bead content. Applicability of the PS beads as a filler in SBR matrix is tested by plotting Mooney-Rivlin or Guth-Smallwood equations. However, mechanical properties of the composite with the beads were not so excellent as those of the composite with carbon black. Crosslinked PS beads are still tentative as a white color reinforcing filler on SBR matrix.

  15. The PS locomotive runs again

    CERN Multimedia

    2001-01-01

    Over forty years ago, the PS train entered service to steer the magnets of the accelerator into place... ... a service that was resumed last Tuesday. Left to right: Raymond Brown (CERN), Claude Tholomier (D.B.S.), Marcel Genolin (CERN), Gérard Saumade (D.B.S.), Ingo Ruehl (CERN), Olivier Carlier (D.B.S.), Patrick Poisot (D.B.S.), Christian Recour (D.B.S.). It is more than ten years since people at CERN heard the rumbling of the old PS train's steel wheels. Last Tuesday, the locomotive came back into service to be tested. It is nothing like the monstrous steel engines still running on conventional railways -just a small electric battery-driven vehicle employed on installing the magnets for the PS accelerator more than 40 years ago. To do so, it used the tracks that run round the accelerator. In fact, it is the grandfather of the LEP monorail. After PS was commissioned in 1959, the little train was used more and more rarely. This is because magnets never break down, or hardly ever! In fact, the loc...

  16. NEOWISE DIAMETERS AND ALBEDOS V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This PDS data set represents a compilation of published diameters, optical albedos, near-infrared albedos, and beaming parameters for minor planets detected by...

  17. The HARP detector at the CERN PS

    CERN Document Server

    Catanesi, M G; Radicioni, E; Simone, S; Edgecock, R; Ellis, M; Robbins, S; Soler, F J P; Gößling, C; Mass, M; Bunyatov, S; Chukanov, A; Klimov, O; Krasin, I; Krasnoperov, A; Kustov, D; Popov, B; Serdiouk, V; Tereshchenko, V; Carassiti, V; Di Capua, E; Evangelisti, F; Vidal-Sitjes, G; Artamonov, A; Arce, P; Brocard, R; Decreuse, G; Friend, B; Giani, S; Gilardoni, S; Gorbunov, p; Grant, A; Grossheim, A; Gruber, P; Ivanchenko, V; Legrand, J C; Kayis-Topaksu,A; Panman, P; Papadopoulos, I; Pasternak, J; Chernyaev, E; Tsukerman, I; van der Vlugt, R; Veenhof, R; Wiebusch, C; Zucchelli, P; Blondel, A; Borghi, S; Campanelli, M; Cervera-Villanueva, A; Morone, M C; Prior, G; Schroeter, R; Kato, I; Gastaldi, Ugo; Mills, G B; Graulich, J S; Grégoire, G; Bonesini, M; Chignoli, F; Ferri, F; Paleari, F; Kirsanov, M; Postoev, V; Bagulya A; Grichine, V; Polukhina, N; Palladino, V; Coney, L; Schmitz, D; Barr, G; De Santo, A; Pattison, C; Zuber, K; Barichello, G; Bobisut, F; Gibin, D; Guglielmi, A; Laveder, M; Menegolli, A; Mezzetto M; Pepato, Adriano; Dumarchez, J; Troquereau, S; Vannucci, F; Dore, U; Iaciofano, A; Lobello, M; Marinilli, F; Orestano, D; Panayotov, D; Pasquali, M; Pastore, F; Tonazzo, A; Tortora, L; Booth, C; Buttar, C; Hodgson, P; Howlett, L; Nicholson, R; Bogomilovw, M; Burin, K; Chizhov, M; Kolev, D; Petev, P; Rusinov, I; Tsenov, R; Piperov, S; Temnikov, P; Apollonio, M; Chimenti, P; Giannini, G; Santin, G; Burguet-Castell, J; Gómez-Cadenas, J J; Novella, P; Sorel, M; Tornero, A

    2007-01-01

    HARP is a high-statistics, large solid angle experiment to measure hadron production using proton and pion beams with momenta between 1.5 and 15 GeV/c impinging on many different solid and liquid targets from low to high Z. The experiment, located in the T9 beam of the CERN PS, took data in 2001 and 2002. For the measurement of momenta of produced particles and for the identification of particle types, the experiment includes a large-angle spectrometer, based on a Time Projection Chamber and a system of Resistive Plate Chambers, and a forward spectrometer equipped with a set of large drift chambers, a threshold Cherenkov detector, a time-of-flight wall and an electromagnetic calorimeter. The large angle system uses a solenoidal magnet, while the forward spectrometer is based on a dipole magnet. Redundancy in particle identification has been sought, to enable the cross-calibration of efficiencies and to obtain a few percent overall accuracy in the cross-section measurements. Detector construction, operation an...

  18. Preparations for Upgrading the RF Systems of the PS Booster

    CERN Document Server

    Albright, Simon; Shaposhnikova, Elena

    2016-01-01

    The accelerators of the LHC injector chain need to be upgraded to provide the HL-LHC beams. The PS Booster, the first synchrotron in the LHC injection chain, uses three different RF systems (first, second and up to tenth harmonic) in each of its four rings. As part of the LHC Injector Upgrade the current ferrite RF systems will be replaced with broadband Finemet cavities, increasing the flexibility of the RF system. A Finemet test cavity has been installed in Ring 4 to investigate its effect on machine performance, especially beam stability, during extensive experimental studies. Due to large space charge impedance Landau damping is lost through most of the cycle in single harmonic operation, but is recovered when using the second harmonic and controlled longitudinal emittance blow-up. This paper compares beam parameters during acceleration with and without the Finemet test cavity. Comparisons were made using beam measurements and simulations with the BLonD code based on a full PS Booster impedance model. Thi...

  19. Formation of positron-atom bound states in collisions between Rydberg Ps and neutral atoms

    CERN Document Server

    Swann, A R; Deller, A; Gribakin, G F

    2016-01-01

    Predicted twenty years ago, positron binding to neutral atoms has not yet been observed experimentally. A new scheme is proposed to detect positron-atom bound states by colliding Rydberg positronium (Ps) with neutral atoms. Estimates of the charge-transfer-reaction cross section are obtained using the first Born approximation for a selection of neutral atom targets and a wide range of incident Ps energies and principal quantum numbers. We also estimate the corresponding Ps ionization cross section. The accuracy of the calculations is tested by comparison with earlier predictions for Ps charge transfer in collisions with hydrogen and antihydrogen. We describe an existing Rydberg Ps beam suitable for producing positron-atom bound states and estimate signal rates based on the calculated cross sections and realistic experimental parameters. We conclude that the proposed methodology is capable of producing such states and of testing theoretical predictions of their binding energies.

  20. Determination of Beam Intensity and Position in a Particle Accelerator

    CERN Document Server

    Kasprowicz, Grzegorz; Raich, Uli

    2011-10-04

    A subject of the thesis is conception, design, implementation, tests and deployment of new position measurement system of particle bunch in the CERN PS circular accelerator. The system is based on novel algorithms of particle position determination. The Proton Synchrotron accelerator (PS), installed at CERN†, although commissioned in 1959, still plays a central role in the production of beams for the Antiproton Decelerator, Super Proton Synchrotron, various experimental areas and for the Large Hadron Collider (LHC)‡. The PS produces beams of different types of particles, mainly protons, but also various species of ions. Almost all these particle beams pass through the PS. The quality of the beams delivered to the LHC has a direct impact on the effective luminosity, and therefore the performance of the instrumentation of the PS is of great importance. The old trajectory and orbit measurement system of the PS is dated back to 1988 and no longer fulfilled present day requirements. It used 40 beam posi...

  1. Determination of beam intensity and position in a particle accelerator

    CERN Document Server

    Kasprowicz, G

    2011-01-01

    A subject of the thesis is conception, design, implementation, tests and deployment of new position measurement system of particle bunch in the CERN PS circular accelerator. The system is based on novel algorithms of particle position determination. The Proton Synchrotron accelerator (PS), installed at CERN, although commissioned in 1959, still plays a central role in the production of beams for the Antiproton Decelerator, Super Proton Synchrotron, various experimental areas and for the Large Hadron Collider (LHC). The PS produces beams of different types of particles, mainly protons, but also various species of ions. Almost all these particle beams pass through the PS. The quality of the beams delivered to the LHC has a direct impact on the effective luminosity, and therefore the performance of the instrumentation of the PS is of great importance. The old trajectory and orbit measurement system of the PS is dated back to 1988 and no longer fulfilled present day requirements. It used 40 beam position monitors...

  2. Laser Beam Focus Analyser

    DEFF Research Database (Denmark)

    Nielsen, Peter Carøe; Hansen, Hans Nørgaard; Olsen, Flemming Ove

    2007-01-01

    The quantitative and qualitative description of laser beam characteristics is important for process implementation and optimisation. In particular, a need for quantitative characterisation of beam diameter was identified when using fibre lasers for micro manufacturing. Here the beam diameter limits...... the obtainable features in direct laser machining as well as heat affected zones in welding processes. This paper describes the development of a measuring unit capable of analysing beam shape and diameter of lasers to be used in manufacturing processes. The analyser is based on the principle of a rotating...... mechanical wire being swept through the laser beam at varying Z-heights. The reflected signal is analysed and the resulting beam profile determined. The development comprised the design of a flexible fixture capable of providing both rotation and Z-axis movement, control software including data capture...

  3. Multipole Stack for the 800 MeV PS Booster

    CERN Multimedia

    1975-01-01

    The 800 MeV PS Booster had seen first beam in its 4 superposed rings in 1972, routine operation began in 1973. In the strive for ever higher beam intensities, the need for additional multipole lenses became evident. After detailed studies, the manufacture of 8 stacks of multipoles was launched in 1974. Each stack consists of 4 superposed multipoles and each multipole has 4 concentric shells. From the innermost to the outermost shell, Type A contains octupole, skew-octupole, sextupole, skew-sextupole. Type B contains skew-octupole, skew-sextupole, vertical dipole, horizontal dipole. Completion of installation in 1976 opened the way to higher beam intensities. M. Battiaz is seen here with a multipole stack and its many electrical connections.

  4. EDH 'Millionaire' in PS Division

    CERN Document Server

    2001-01-01

    Christmas cheer! Left to right: Gerard Lobeau receives a bottle of Champagne from Derek Mathieson and Jurgen De Jonghe in recognition of EDH's millionth document. At 14:33 on Monday 3 December a technician in PS division, Gerard Lobeau, unwittingly became part of an important event in the life of CERN's Electronic Document Handling system (EDH). While ordering some pieces of aluminum for one of the PS's 10Mhz RF cavities, he created EDH document number 1,000,000. To celebrate the event Derek Mathieson (EDH Project Leader) and Jurgen De Jonghe (Original EDH Project Leader) presented Mr Lobeau with a bottle of champagne. As with 93% of material requests, Mr Lobeau's order was delivered within 24 hours. 'I usually never win anything' said Mr Lobeau as he accepted his prize, 'I initially though there may have been a problem with EDH when the document number had so many zeros in it, and was then surprised to get a phone call from you a few minutes later.' The EDH team had been monitoring the EDH document number ...

  5. Thermal stability of gold-PS nanocomposites thin films

    Indian Academy of Sciences (India)

    Administrator

    subsequently spin-coated on a carbon-coated copper grid for TEM measurements. TEM measurements were performed at liquid nitrogen temperatures to reduce the electron–beam-induced radiation damage. The results showed a marginal increase in Au nanoparticle diameter (2⋅3 nm–3⋅6 nm) and more importantly,.

  6. Phase morphological study on SEBS compatibilized PS/LDPE blends

    Directory of Open Access Journals (Sweden)

    Chatchai Kunyawut

    2014-09-01

    Full Text Available The co-continuous phase morphology of polystyrene (PS/low density polyethylene (LDPE blends compatibilized with poly(styrene-block-ethylene/butylene-block-styrene triblock copolymers (SEBS with varying molecular weights has been investigated. The blend samples were prepared in a mini-twin screw extruder. The barrel length and diameter are 224 and 16 mm, respectively. The diameter of the capillary die is 1 mm. The concentration of the blends was 70/30 wt% of PS/LDPE while that of the SEBS used was 5 wt% of the blend. The mixing temperatures used were 180, 250, and 280o C, and a screw speed of 60 rpm. The morphology of the blends was investigated using an AFM technique. Average droplet diameters of the blend samples were determined using an OM technique. The co-continuous morphology has not been obtained in all the blends, although the mixing temperature used is as high as 280o C. The experimental results indicated that the model prediction of the co-continuous morphology proposed by Willemse and co-worker was not applicable to the blend systems studied. Only droplet-type dispersion was observed. This is considered to arise from the processing conditions and the mixing device used. The blend compatibilized with the high molecular weight SEBS had higher dispersed phase size than that of the blend compatibilized with the medium and low molecular weight SEBSs. This behaviour is likely to arise from coalescence during melt processing.

  7. A fast wire scanner, used to measure the transverse density distribution of beams circulating in an accelerator or storage ring.

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    Fast wire scanners are used to measure the transverse density distribution of beams circulating in an accelerator or storage ring. In order to minimize blow-up of the beam through multiple Coulomb scattering, the wires are very thin (in the version shown here it is actually a twisted strand of carbon fibres with a total diameter of about 25 microns) and are swept through the beam at high speed (a linear motor, not mounted here, accelerates the wires to up to 20 m/s). One measures either the secondary emission current from the wire, or the signal from a scintillator/photomultiplier combination downstream from the wire scanner receiving the shower from nuclear reactions of beam particles with the wire nuclei. There are four such fast wire scanners in the 26 GeV PS and eight in the 1.4 GeV Booster.

  8. The DIAMET campaign

    Science.gov (United States)

    Vaughan, G.

    2012-04-01

    DIAMET (DIAbatic influences on Mesoscale structures in ExTratropical storms) is a joint project between the UK academic community and the Met Office. Its focus is on understanding and predicting mesoscale structures in synoptic-scale storms, and in particular on the role of diabatic processes in generating and maintaining them. Such structures include fronts, rain bands, secondary cyclones, sting jets etc, and are important because much of the extreme weather we experience (e.g. strong winds, heavy rain) comes from such regions. The project conducted two field campaigns in the autumn of 2011, from September 14 - 30 and November 24 - December 14, based around the FAAM BAe146 aircraft with support from ground-based radar and radiosonde measurements. Detailed modelling, mainly using the Met Office Unified model, supported the planning and interpretation of these campaigns. This presentation will give a brief overview of the campaigns. Both in September and November-December the weather regime was westerly, with a strong jet stream directed across the Atlantic. Three IOPs were conducted in September, to observe a convective band ahead of an upper-level trough, waves on a long trailing cold front, and a warm conveyor belt associated with a secondary cyclone. In November-December six IOPs were conducted, to observe frontal passages and high winds. This period was notable for a number of very strong windstorms passing across the north of the UK, and gave us an opportunity to examine bent-back warm fronts in the southern quadrant of these storms where the strongest winds are found. The case studies fell into two basic patterns. In the majority of cases, dropsonde legs at high level were used to obtain a cross-section of winds and thermodynamic structure (e.g. across a front), followed by in situ legs at lower levels (generally where the temperature was between 0 and -10°) to examine microphysical processes, especially ice multiplication and the extent of supercooled water

  9. Investigation of microstructure and morphology for the Ge on porous silicon/Si substrate hetero-structure obtained by molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Gouder, S. [IM2NP Aix-Marseille Universités, UMR CNRS n°7334, Faculté des Sciences St-Jérôme - Case 142, 13397 Marseille Cedex 20 France (France); Electronics Department, University Hadj Lakhdar, Batna 05000 (Algeria); Mahamdi, R. [Electronics Department, University Hadj Lakhdar, Batna 05000 (Algeria); Aouassa, M.; Escoubas, S.; Favre, L.; Ronda, A.; Berbezier, I. [IM2NP Aix-Marseille Universités, UMR CNRS n°7334, Faculté des Sciences St-Jérôme - Case 142, 13397 Marseille Cedex 20 France (France)

    2014-01-01

    Thick porous silicon (PS) buffer layers are used as sacrificial layers to epitaxially grow planar and fully relaxed Ge membranes. The single crystal Ge layers have been deposited by molecular beam epitaxy (MBE) on PS substrate. During deposition, the pore network of PS layers has been filled with Ge. We investigate the structure and morphology of PS as fabricated and after annealing at various temperatures. We show that the PS crystalline lattice is distorted and expanded in the direction perpendicular to the substrate plane due to the presence of chemisorbed –OH. An annealing at high temperature (> 500 °C), greatly changes the PS morphology and structure. This change is marked by an increase of the pore diameter while the lattice parameter becomes tensily strained in the plane (compressed in the direction perpendicular). The morphology and structure of Ge layers are investigated by transmission electron microscopy, high resolution X-ray diffraction and atomic force microscopy as a function of the deposition temperature and deposited thickness. The results show that the surface roughness, level of relaxation and Si-Ge intermixing (Ge content) depend on the growth temperature and deposited thickness. Two sub-layers are distinguished: the layer incorporated inside the PS pores (high level of intermixing) and the layer on top of the PS surface (low level of intermixing). When deposited at temperature > 500 °C, the Ge layers are fully relaxed with a top Si{sub 1−x}Ge{sub x} layer x = 0.74 and a very flat surface. Such layer can serve as fully relaxed ultra-thin SiGe pseudo-substrate with high Ge content. The epitaxy of Ge on sacrificial soft PS pseudo-substrate in the experimental conditions described here provides an easy way to fabricate fully relaxed SiGe pseudo-substrates. Moreover, Ge thin films epitaxially deposited by MBE on PS could be used as relaxed pseudo-substrate in conventional microelectronic technology. - Highlights: • We have developed a rapid

  10. 29 mm Diameter Target Test Report

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Olivas, Eric Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Naranjo, Angela Carol [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Romero, Frank Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chemerisov, Sergey [Argonne National Lab. (ANL), Argonne, IL (United States); Gromov, Roman [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-10-23

    After numerous delays, the test of the 29 mm diameter target was conducted on 8/18/2017. The complete target design report, dated 8/15/2016, is reproduced below for completeness. This describes in detail the 10 disk target with varying thickness disks. The report presents and discusses the test results. In brief summary, there appears to have been multiple instrumentation errors. Measured temperatures, pressures and IR camera window temperature measurement are all suspect. All tests were done at 35 MeV, with 171 μA current, or 6 kW of beam power.

  11. PS potential performance with a higher injection energy

    CERN Document Server

    Gilardoni, S; Borburgh, J; Bodart, D; Chiggiato, P; Damerau, H; Hancock, S; Metral, G; Pittet, S; Rossi, C; Rumolo, G; Steerenberg, R; Widorski, M

    2011-01-01

    In the context of the LHC Injectors upgrade project, the PS has to be brought up to − and to operate reliably at − the level of performance required by the HL-LHC until the end of the LHC lifetime. The study has started on the potential benefits of increasing the injection energy. An overview of the impact of this upgrade will be presented, with a preliminary estimate of the beam characteristics at the SPS entrance and the remaining performance limitations. The necessary hardware modifications will be described, highlighting the critical systems and the risks. The program for the 2011 machine studies and hardware interventions for refining these plans will be presented.

  12. Reliability and maintenance analysis of the CERN PS booster

    CERN Document Server

    Staff, P S B

    1977-01-01

    The PS Booster Synchrotron being a complex accelerator with four superposed rings and substantial additional equipment for beam splitting and recombination, doubts were expressed at the time of project authorization as to its likely operational reliability. For 1975 and 1976, the average down time was 3.2% (at least one ring off) or 1.5% (all four rings off). The items analysed are: operational record, design features, maintenance, spare parts policy, operating temperature, effects of thunderstorms, fault diagnostics, role of operations staff and action by experts. (15 refs).

  13. A multiturn measurement system for the CERN PS

    CERN Document Server

    Angoletta, Maria Elena

    2002-01-01

    Multiturn beam position measurements on one or more pickups provide very important information needed to derive machine optics parameters. A variety of analyses is possible, such as determination of phase advance, detuning with amplitude, and most important, the exploration of phase space. In this paper we present a new multiturn acquisition system for the CERN proton synchrotron (CERN PS) based on a compact PCI fast digitiser and a new general object-oriented visualisation and analysis tool for the acquired multiturn data. (11 refs).

  14. Fast timing with plastic scintillators for in-beam heavy-ion spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hoischen, R., E-mail: robert.hoischen@nuclear.lu.se [Department of Physics, Lund University, SE-22100 Lund (Sweden); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); Pietri, S. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); Rudolph, D. [Department of Physics, Lund University, SE-22100 Lund (Sweden); Prokopowicz, W.; Schaffner, H. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); Emde, S. [Lehrstuhl fuer Operations Management, Friedrich-Schiller-Universitaet Jena, D-07743 Jena (Germany); Golubev, P. [Department of Physics, Lund University, SE-22100 Lund (Sweden); Wendt, A. [Institut fuer Kernphysik, Universitaet zu Koeln, D-50937 Koeln (Germany); Kurz, N.; Wollersheim, H.J.; Gerl, J. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany)

    2011-10-21

    The design, R and D, and testing of a new plastic-scintillator detector for Time-of-Flight measurements with relativistic heavy-ion beams are presented. A design approach using 32 independent precise timing measurements of the same physical event is followed. This is different from the conventional scheme, which aims at two or four high-precision measurements. A circular, 27 cm in diameter, BC-420 plastic-scintillator sheet is read-out by 32 photomultiplier tubes in order to achieve an intrinsic detector resolution on the order of 10 ps root mean square.

  15. Space Charge effects and mitigation in the CERN PS Booster, in view of the Upgrade

    CERN Document Server

    AUTHOR|(CDS)2068441; Cieslak-Kowalska, Magdalena Anna; Forte, Vincenzo; Schmidt, Frank

    2016-01-01

    The CERN PS Booster (PSB) is presently running with a space charge tune spread larger than 0.5 at injection. Since the High Luminosity LHC (HL-LHC) will require beams with twice the intensity and brightness of today, the LHC Injector Upgrade (LIU) Project is putting in place an upgrade program for all the injector chain and, in particular, it relies on the important assumption that the PS Booster can successfully produce these beams after the implementation of the 160 MeV H- injection from Linac4. This contribution describes the studies (measure-ments and simulations) that have been carried out to con- firm that the PSB can indeed perform as needed in terms of beam brightness for the future HL-LHC runs. The importance of the mitigation measures already in place, such as the correction of the half-integer line, and the effects of non-linear resonances on the beam are also discussed.

  16. Academic Training Lecture Regular Programme: Physics at the AD/PS/SPS

    CERN Multimedia

    2012-01-01

    Physics at the AD/PS/SPS (1/4), by Lau Gatignon (CERN).   Monday, June 18, 2012 from 11:00 to 12:00 (Europe/Zurich) at CERN ( 222-R-001 - Filtration Plant )   Lecture 1: The CERN injector complex and beams for non-LHC physics. The various machines and beam lines in the CERN injector complex are presented, from the linacs to the SPS. Special emphasis is given to the beam lines at the PS and SPS machines: AD, North and East Areas, nTOF and CNGS and HiRadMad as well as the ion beams. A short outlook is given to possible future upgrades and projects.   More information here.  

  17. Evaluation of enamel surface modification using PS-OCT after laser treatment to increase resistance to demineralization

    Science.gov (United States)

    Kim, Jin Wan; Chan, Kenneth H.; Fried, Daniel

    2016-02-01

    At laser intensities below ablation, carbonated hydroxyapatite in enamel is converted into a purer phase hydroxyapatite with increased acid resistance. Previous studies suggested the possibility of achieving the conversion without surface modification. This study attempts to evaluate the thresholds for the modification without additional changes in physical and optical properties of the enamel. Bovine specimens were irradiated using an RF-excited CO2 laser operating at 9.4-μm with a pulse duration of 26- μs, pulse repetition rates of 100-1000 Hz, with a Gaussian spatial beam profile - 1.4 mm in diameter. After laser treatment, the samples were subjected to acid demineralization for 48 hours to simulate acidic intraoral conditions of a caries attack. The resulting demineralization and erosion were assessed using polarization sensitive OCT (PS-OCT) and 3D digital microscopy. The images from digital microscopy demonstrated a clear delineation between laser protected zones without visual changes and zones with higher levels of demineralization and erosion. Distinct changes in the surface morphology were found within the laser treated area in accordance with the Gaussian spatial beam profile. There was significant protection from the laser in areas that were not visually altered.

  18. Gaussian Beam Intensity Flattener

    Science.gov (United States)

    Griffin, DeVon W.

    1998-01-01

    The goal of this investigation was to use commercial elements and extend the correction to a 1/e(sup 2) diameter of 3 mm over long propagation distances. Shafer discussed the use of spherical elements to generate a uniform beam to the 1/e diameter.

  19. Beam-beam instability

    Energy Technology Data Exchange (ETDEWEB)

    Chao, A.W.

    1983-08-01

    The subject of beam-beam instability has been studied since the invention of the colliding beam storage rings. Today, with several colliding beam storage rings in operation, it is not yet fully understood and remains an outstanding problem for the storage ring designers. No doubt that good progress has been made over the years, but what we have at present is still rather primitive. It is perhaps possible to divide the beam-beam subject into two areas: one on luminosity optimization and another on the dynamics of the beam-beam interaction. The former area concerns mostly the design and operational features of a colliding beam storage ring, while the later concentrates on the experimental and theoretical aspects of the beam-beam interaction. Although both areas are of interest, our emphasis is on the second area only. In particular, we are most interested in the various possible mechanisms that cause the beam-beam instability.

  20. beam-beam interaction

    CERN Multimedia

    2017-01-01

    The Beam 1 (represented in blue) and the Beam 2 (represented in red) are colliding with an angle at the Interaction Point (IP). The angle is needed to avoid unwanted multiple collisions along the interaction region. Despite of the separation introduced by the angle, the two beams interact via their electromagnetic field, the so called "beam-beam" interaction.

  1. Projection imaging with directional electron and proton beams emitted from an ultrashort intense laser-driven thin foil target

    Science.gov (United States)

    Nishiuchi, M.; Choi, I. W.; Daido, H.; Nakamura, T.; Pirozhkov, A. S.; Yogo, A.; Ogura, K.; Sagisaka, A.; Orimo, S.; Daito, I.; Bulanov, S. V.; Sung, J. H.; Lee, S. K.; Yu, T. J.; Jeong, T. M.; Kim, I. J.; Kim, C. M.; Kang, S. W.; Pae, K. H.; Oishi, Y.; Lee, J.

    2015-02-01

    Projection images of a metal mesh produced by directional MeV electron beam together with directional proton beam, emitted simultaneously from a thin foil target irradiated by an ultrashort intense laser, are recorded on an imaging plate for the electron imaging and on a CR-39 nuclear track detector for the proton imaging. The directional electron beam means the portion of the electron beam which is emitted along the same direction (i.e., target normal direction) as the proton beam. The mesh patterns are projected to each detector by the electron beam and the proton beam originated from tiny virtual sources of ~20 µm and ~10 µm diameters, respectively. Based on the observed quality and magnification of the projection images, we estimate sizes and locations of the virtual sources for both beams and characterize their directionalities. To carry out physical interpretation of the directional electron beam qualitatively, we perform 2D particle-in-cell simulation which reproduces a directional escaping electron component, together with a non-directional dragged-back electron component, the latter mainly contributes to building a sheath electric field for proton acceleration. The experimental and simulation results reveal various possible applications of the simultaneous, synchronized electron and proton sources to radiography and pump-probe measurements with temporal resolution of ~ps and spatial resolution of a few tens of µm.

  2. New Electron Cloud Detectors for the PS Main Magnets

    CERN Document Server

    Yin Vallgren, Ch; Gilardoni, S; Taborelli, M; Neupert, H; Ferreira Somoza, J

    2014-01-01

    Electron cloud (EC) has already been observed during normal operation of the PS, therefore it is necessary to study its in fluence on any beam instability for the future LHC Injector Upgrade (LIU). Two new electron cloud detectors have been discussed, developed and installed during the Long Shutdown (LS1) in one of the PS main magnets. The first measurement method is based on current measurement by using a shielded button-type pick-up. Due to the geometry and space limitation in the PS magnet, the button-type pick-up made of a 96%Al2O3 block coated with a thin layer of solvent-based Ag painting, placed 30 degrees to the bottom part of the vacuum chamber was installed in the horizontal direction where the only opening of the magnet coil is. The other newly developed measurement method is based on detection of photons emitted by the electrons from the electron cloud impinging on the vacuum chamber walls. The emitted photons are reected to a quartz window. A MCP-PMT (Micro-Channel Plate Photomultiplier Tube) wit...

  3. Ps-atom scattering at low energies

    CERN Document Server

    Fabrikant, I I

    2015-01-01

    A pseudopotential for positronium-atom interaction, based on electron-atom and positron-atom phase shifts, is constructed, and the phase shifts for Ps-Kr and Ps-Ar scattering are calculated. This approach allows us to extend the Ps-atom cross sections, obtained previously in the impulse approximation [Phys. Rev. Lett. 112, 243201 (2014)], to energies below the Ps ionization threshold. Although experimental data are not available in this low-energy region, our results describe well the tendency of the measured cross sections to drop with decreasing velocity at $v<1$ a.u. Our results show that the effect of the Ps-atom van der Waals interaction is weak compared to the polarization interaction in electron-atom and positron-atom scattering. As a result, the Ps scattering length for both Ar and Kr is positive, and the Ramsauer-Townsend minimum is not observed for Ps scattering from these targets. This makes Ps scattering quite different from electron scattering in the low-energy region, in contrast to the inter...

  4. Enhanced personal protection at the PS

    CERN Multimedia

    Samuel Morier Genoud

    2013-01-01

    Pictures 03, 06, 07 08 : Pierre Ninin, deputy group leader of GS-ASE and responsible for the installation of the new PS complex safety system, in front of a new access control system.Pictures 10, 12 ,13 : View of Building 271, the future control centre of the new PS complex safety system.

  5. PS, SL and LHC Auditoria change names

    CERN Document Server

    2003-01-01

    Following the replacement of the PS, SL and LHC Divisions by the AB and AT Divisions, the Auditoria are also changing their names. PS Auditorium is renamed AB Meyrin SL Auditorium is renamed AB Prévessin LHC Auditorium is renamed AT

  6. Space Charge measurements in the PS at 2GeV.

    CERN Document Server

    Benedetto, E

    2012-01-01

    This note summarizes the 2011 Space-Charge studies in the PS on the $2$~GeV plateau and in particular it reports the results of the systematic measurements made on 9-10th November'11 with a low-emittance (LHC-type) beam.

  7. Orbit, optics and chromaticity correction for PS2 negative momentum compaction lattices

    Energy Technology Data Exchange (ETDEWEB)

    Papaphilippou,Y.; Barranco, J.; Bartmann, W.; Benedikt, M.; Carli, C.; de Maria, R.; Peggs, S.; Trbojevic, D.

    2009-05-04

    The effect of magnet misalignments in the beam orbit and linear optics functions are reviewed and correction schemes are applied to the negative momentum compaction lattice of PS2. Chromaticity correction schemes are also proposed and tested with respect to off-momentum optics properties. The impact of the correction schemes in the dynamic aperture of the lattice is finally evaluated.

  8. Wheel Diameter and Speedometer Reading

    Science.gov (United States)

    Murray, Clifton

    2010-01-01

    Most introductory physics students have seen vehicles with nonstandard wheel diameters; some may themselves drive "low-rider" cars or "big-wheel" pickup trucks. But how does changing wheel diameter affect speedometer readout for a given speed? Deriving the answer can be followed readily by students who have been introduced to rotation, and it…

  9. On the crystallization behavior of syndiotactic-b-atactic polystyrene stereodiblock copolymers, atactic/syndiotactic polystyrene blends, and aPS/sPS blends modified with sPS-b-aPS

    Energy Technology Data Exchange (ETDEWEB)

    Annunziata, Liana, E-mail: liana.annunziatta@univ-rennes1.fr [Organométalliques et Catalyse, UMR 6226 Sciences Chimiques CNRS, Université de Rennes 1, Campus de Beaulieu, F-35042 Rennes Cedex (France); Monasse, Bernard, E-mail: bernard.monasse@mines-paristech.fr [Mines-ParisTech, CEMEF, Centre de Mise en Forme des Matériaux, UMR CNRS 7635, Sophia Antipolis (France); Rizzo, Paola; Guerra, Gaetano [Dipartimento di Chimica e Biologia, Università degli studi di Salerno, Via Ponte don Melillo, I-84084 Fisciano, SA (Italy); Duc, Michel [Total Petrochemicals Research Feluy, Zone Industrielle Feluy C, B-7181 Seneffe (Belgium); Carpentier, Jean-François, E-mail: jean-francois.carpentier@univ-rennes1.fr [Organométalliques et Catalyse, UMR 6226 Sciences Chimiques CNRS, Université de Rennes 1, Campus de Beaulieu, F-35042 Rennes Cedex (France)

    2013-09-16

    Crystallization and morphological features of syndiotactic-b-atactic polystyrene stereodiblock copolymers (sPS-b-aPS), atactic/syndiotactic polystyrene blends (aPS/sPS), and aPS/sPS blends modified with sPS-b-aPS, with different compositions in aPS and sPS, have been investigated using differential scanning calorimetry (DSC), polarized light optical microscopy (POM) and wide angle X-ray diffraction (WAXRD) techniques. For comparative purposes, the properties of parent pristine sPS samples were also studied. WAXRD analyses revealed for all the samples, independently from their composition (aPS/sPS ratio) and structure (blends, block copolymers, blends modified with block copolymers), the same polymorphic β form of sPS. The molecular weight of aPS and sPS showed opposite effects on the crystallization of 50:50 aPS/sPS blends: the lower the molecular weight of aPS, the slower the crystallization while the lower the molecular weight of sPS, the faster the crystallization. DSC studies performed under both isothermal and non-isothermal conditions, independently confirmed by POM studies, led to a clear trend for the crystallization rate at a given sPS/aPS ratio (ca. 50:50 and 20:80): sPS homopolymers > sPS-b-aPS block copolymers ∼sPS/aPS blends modified with sPS-b-aPS copolymers > sPS/aPS blends. Interestingly, sPS-b-aPS block copolymers not only crystallized faster than blends, but also affected positively the crystallization behavior of blends. At 50:50 sPS/aPS ratio, blends (Blend-2), block copolymers (Cop-1) and blends modified with block copolymers (Blend-2-mod) crystallized via spherulitic crystalline growth controlled by an interfacial process. In all cases, an instantaneous nucleation was observed. The density of nuclei in block copolymers (160,000−190,000 nuclei mm{sup −3}) was always higher than that in blends and modified blends (30,000−60,000 nuclei mm{sup −3}), even for quite different sPS/aPS ratio. At 20:80 sPS/aPS ratio, the block copolymers

  10. The 1.4 GeV PS Booster in its tunnel.

    CERN Multimedia

    Patrice Loïez

    2002-01-01

    The PS Improvement Programme, launched as early as 1964, had a "Booster" as the key element in the quest for higher beam intensity and density. These were limited in the PS at injection of the 50 MeV proton beam from the linac by the incoherent (Laslett-) Q-shift. Boosting the linac beam to 800 MeV would raise the PS intensity limit by an order of magnitude, from 1E12 protons per pulse to 1E13. The main motivation was the supply of intense beams to the ISR. Soon, the Booster proved to be crucial for the neutral current experiment. A unique feature of the Booster are its 4 superposed rings. Its lattice is also unusual: between its 32 bending magnets, every second straight section contains a quadrupole triplet (F,D,F), while the alternate ones are drift spaces (mostly filled with essential components like septa, kickers, RF-cavities, etc.). In each picture we see one of the 16 periods. Following the direction of the beam from right to left: a bending magnet (green); an empty straight section; a bending magnet; ...

  11. Measurement and Compensation of Second and Third Order Resonances at the CERN PS Booster

    CERN Document Server

    Urschütz, Peter

    2004-01-01

    Space charge effects at injection are the most limiting factor for the production of high brightness beams in the CERN PS Booster. The beams for LHC, CNGS and ISOLDE feature incoherent tune spreads exceeding 0.5 at injection energy and thus cover a large area in the tune diagram. Consequently these beams experience the effects of transverse betatron resonances and efficient compensation is required. Several measurements have been performed at the PS Booster in 2003, aiming at a detailed analysis of all relevant second and third order resonances and an optimisation of the compensation schemes. Special attention was paid to the systematic 3Qv=16 resonance. To avoid this particularly dangerous resonance an alternative working point was tested. A comparison of resonance driving terms and compensation settings for both working points was made and important differences in the strengths of the resonances were found. The peculiarities when measuring third order coupling resonance driving terms are also mentioned.

  12. Ps 22 in Gospels’ interpretation of Passion

    Directory of Open Access Journals (Sweden)

    Sylwester Jędrzejewski

    2012-09-01

    Full Text Available Ps 22 is a piece of artistically high poetry, clear images and metaphors, historical and prophetic references. The conviction of biblical scholars that the New Testament writers has recognized in Ps 22 prophetic witness of passion, accompanies the Church from its beginnings. The words of Jesus on the cross, taken from Ps 22: 2, have a character of lamentable re-symbolization of the prayer of Israel. These words establish a theological answer in the form of suitable credo as well. Dramatic question “why?” is connected with a proclamation and identification “My God”. The personal experience of oppression and death is included by Jesus in the history of his nation and in the experience of God. Ps 22 in the Gospels’ passion context becomes a proclamation form of prayer and a very personal, expressed in such dramatic circumstances confession of the faith.

  13. Yasp for LEIR to PS injection

    CERN Document Server

    Kain, V; Bartosik, H; Huschauer, A; Jacquet, D; Nicosia, D; Pasinelli, S; Wenninger, J

    2017-01-01

    The steering program YASP was introduced in the LEIRinjection as well as the extraction lines in 2016 to correctthe trajectories with well-known model based correctionalgorithms such as MICADO or SVD. In addition a YASPconfiguration was prepared to correct the extraction linetogether with the first turn of the PS. In this way the injectionoscillations can be corrected while keeping the trajectoryreasonable in the PS injection line.

  14. PS overcomes two serious magnet failures

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    Two magnets and a bus bar connection in the PS were found to be faulty during high-voltage tests at the end of the accelerator shutdown. A five-week repair schedule was quickly devised. A team of mechanics, technicians and engineers worked at full speed to replace the faulty magnets, succeeding in limiting the delay of the accelerators' spring start-up to two weeks. Here we see the PS magnet string awaiting the replacement no. 6 magnet.

  15. Simulation of Instability at Transition Energy with a New Impedance Model for CERN PS

    CERN Document Server

    Wang, Na; Biancacci, Nicolo; Migliorati, Mauro; Persichelli, Serena; Sterbini, Guido

    2016-01-01

    Instabilities driven by the transverse impedance are proven to be one of the limitations for the high intensity reach of the CERN PS. Since several years, fast single bunch vertical instability at transition energy has been observed with the high intensity bunch serving the neu-tron Time-of-Flight facility (n-ToF). In order to better understand the instability mechanism, a dedicated meas-urement campaign took place. The results were compared with macro-particle simulations with PyHEADTAIL based on the new impedance model developed for the PS. Instability threshold and growth rate for different longitu-dinal emittances and beam intensities were studied.

  16. Low energy o-Ps-o-Ps elastic scattering using a simple model

    Energy Technology Data Exchange (ETDEWEB)

    Himanshu, Sharma [Veer Kunwar Singh Univ., Dept. of Physics, Bihar (India); Kiran, Kumari [R N College, P. G. Dept. of Physics, Bihar (India); Sumana, Chakraborty [Indian Association for the Cultivation of Science, Dept. of Theoretical Physics (India)

    2009-06-15

    A simple model is employed to investigate o-Ps-o-Ps (positronium-positronium) scattering at low energies. This model contains the effect of exchange explicitly and a model long range potential in the framework of static-exchange model. These two physical features are of key importance in Ps-Ps (atom-atom) scattering system. S-wave triplet-triplet and singlet-singlet scattering lengths and corresponding phase shifts up to the incident momentum k = 0.5 a.u. are in excellent agreement with those yielded by most elaborate and theoretically sound predictions. (authors)

  17. Sunsets and Solar Diameter Measurement

    Science.gov (United States)

    Sigismondi, Costantino

    2012-03-01

    A sunset over the sea surface offers the possibility to chronometrate a solar transit across the horizon. The vertical solar diameter is proportional to the duration of the sunset, the cosine of the azimuth and the cosine of the latitude of the observing site. The same formula applies to every circle of equal height, called in arabic almucantarat, and it is exploited in the measurements of the solar diameter made with the Danjon's solar astrolabes. The analogies between sunsets and astrolabes observations are presented, showing advantages and sources of errors of these methods of solar astrometry.

  18. The Merit(nTOF-11) High Intensity Liquid Mercury Target Experiment at the CERN PS

    CERN Document Server

    Efthymiopoulos, I; Caretta, O; Carroll, A J; Fabich, A; Graves, V B; Grudiev, A; Haug, F; Kirk, H G; Lettry, Jacques; Loveridge, P; McDonald, K T; Mokhov, N; Palm, M; Park, H; Pernegger, H; Spampinato, P T; Steerenberg, R; Striganov, S; Tsang, T

    2008-01-01

    The MERIT(nTOF-11) experiment is a proof-ofprinciple test of a target system for a high power proton beam to be used as front-end for a neutrino factory or a muon collider. The experiment took data in autumn 2007 with the fast-extracted beam from the CERN Proton Synchrotron (PS) to a maximum intensity of $30 × 10^{12}$ per pulse. The target system, based on a free mercury jet, is capable of intercepting a 4-MW proton beam inside a 15-T magnetic field required to capture the low energy secondary pions as the source for intense muon beams. Partice detectors installed around the target setup measure the secondary particle flux out of the target and can probe cavitation effects in the mercury jet when excited by an intense proton beam.Preliminary results of the data analysis will be presented here.

  19. Diameter Measurement in Bald Cypress

    Science.gov (United States)

    Bernard R. Parresol; James E. Hotvedt

    1990-01-01

    The usual practice of measuring diameter at 4.5 feet ( 1.3 m) or Dbh is meaningless in wetland tree species such as bald cypress (Taxodium distichum (L.) Rich.), due to the presence of fluted basal swells. Since buttress dimensions usually have no consistent relation to volume or form in the tree, the current practice among...

  20. PMMA/PS coaxial electrospinning: core-shell fiber morphology as a function of material parameters

    Science.gov (United States)

    Rahmani, Shahrzad; Arefazar, Ahmad; Latifi, Masoud

    2017-03-01

    Core-shell fibers of polymethyl methacrylate (PMMA) and polystyrene (PS) have been successfully electrospun by coaxial electrospinning. To evaluate the influence of the solvent on the final fiber morphology, four types of organic solvents were used in the shell solution while the core solvent was preserved. Morphological observations with scanning electron microscopy, transmission electron microscopy and optical microscopy revealed that both core and shell solvent properties were involved in the final fiber morphology. To explain this involvement, alongside a discussion of the Bagley solubility graph of PS and PMMA, a novel criterion based on solvent physical properties was introduced. A theoretical model based on the momentum conservation principle was developed and applied for describing the dependence of the core and shell diameters to their solvent combinations. Different concentrations of core and shell were also investigated in the coaxial electrospinning of PMMA/PS. The core-shell fiber morphologies with different core and shell concentrations were compared with their single electrospun fibers.

  1. An Antiproton Decelerator in the CERN PS Complex

    CERN Document Server

    Riunaud, J P; Baird, S A; Boillot, J; Bosser, Jacques; Brouet, M; Caspers, Friedhelm; Chanel, M; Chohan, V; Eriksson, T; Garoby, R; Giannini, R; Giovannozzi, Massimo; Gruber, J; Hémery, J Y; Koziol, Heribert; MacCaferri, R; Maury, S; Metzmacher, K D; Möhl, D; Mulder, H; Pedersen, F; Perriollat, F; Poncet, Alain; Riunaud, J P; Serre, C; Simon, Daniel Jean; Tranquille, G; Tuyn, Jan Willem Nicolaas; Williams, B; Williams, D J

    1996-01-01

    The present CERN PS low-energy antiproton complex involves 4 machines to collect, cool, decelerate and supply experiments with up to 1010 antiprotons per pulse and per hour of momenta ranging from 0.1 to 2 GeV/c. In view of a possible future physics programme requiring low energy antiprotons, mainly to carry out studies on antihydrogen, a simplified scheme providing at low cost antiprotons at 100 MeV/c has been studied. It requires only one machine, the present Antiproton Collector (AC) converted into a cooler and decelerator (Antiproton Decelerator, AD) and delivering beam to experiments in the hall of the present Antiproton Accumulator Complex (AAC) [1]. This paper describes the feasibility study of such a scheme [2].

  2. Generation of a high-brightness pulsed positron beam for the Munich scanning positron microscope

    Energy Technology Data Exchange (ETDEWEB)

    Piochacz, Christian

    2009-11-20

    Within the present work the prerequisites for the operation of the Munich scanning positron microscope (SPM) at the high intense neutron induced positron source Munich (NEPOMUC) were established. This was accomplished in two steps: Firstly, a re-moderation device was installed at the positron beam facility NEPOMUC, which enhances the brightness of the positron beam for all connected experiments. The second step was the design, set up and initial operation of the SPM interface for the high efficient conversion of the continuous beam into a bunched beam. The in-pile positron source NEPOMUC creates a positron beam with a diameter of typically 7 mm, a kinetic energy of 1 keV and an energy spread of 50 eV. The NEPOMUC re-moderator generates from this beam a low energy positron beam (20 - 200 eV) with a diameter of less than 2 mm and an energy spread well below 2.5 eV. This was achieved with an excellent total efficiency of 6.55{+-}0.25 %. The re-moderator was not only the rst step to implement the SPM at NEPOMUc, it enables also the operation of the pulsed low energy positron beam system (PLEPS). Within the present work, at this spectrometer rst positron lifetime measurements were performed, which revealed the defect types of an ion irradiated uranium molybdenum alloy. Moreover, the instruments which were already connected to the positron beam facility bene ts considerably of the high brightness enhancement. In the new SPM interface an additional re-moderation stage enhances the brightness of the beam even more and will enable positron lifetime measurements at the SPM with a lateral resolution below 1 {mu}m. The efficiency of the re-moderation process in this second stage was 24.5{+-}4.5 %. In order to convert high efficiently the continuous positron beam into a pulsed beam with a repetition rate of 50 MHz and a pulse duration of less than 50 ps, a sub-harmonic pre-bucher was combined with two sine wave bunchers. Furthermore, the additional re-moderation stage of the

  3. Studies of Space Charge Effects in the Proposed CERN PS2

    Energy Technology Data Exchange (ETDEWEB)

    Qiang, Ji; /LBL, Berkeley; Ryne, Robert; /LBL, Berkeley; De Maria, Riccardo; /Brookhaven; Macridin, Alexandru; /Fermilab; Spentzouris, Panagiotis; /Fermilab; Papaphilippou, Yannis; /CERN; Wienands, Ulrich; /SLAC

    2012-06-22

    A new proton synchrotron, the PS2, is under design study to replace the current proton synchrotron at CERN for the LHC upgrade. Nonlinear space charge effects could cause significant beam emittance growth and particle losses and limit the performance of the PS2. In this paper, we report on studies of the potential space-charge effects at the PS2 using three-dimensional self-consistent macroparticle tracking codes, IMPACT, MaryLie/IMPACT, and Synergia. We will present initial benchmark results among these codes. Effects of space-charge on the emittance growth, especially due to synchrotron coupling, aperture sizes, initial painted distribution, and RF ramping scheme will also be discussed.

  4. Emerging ps-TW CO{sub 2} laser technology for high energy physics applications

    Energy Technology Data Exchange (ETDEWEB)

    Pogorelsky, I.V.

    1998-02-01

    A brief overview of laser acceleration techniques and a comparative analysis of the picosecond terawatt (ps-TW) CO{sub 2} laser technology versus T{sup 3} solid state lasers for prospective HEP applications. Special attention is given to two laser accelerator schemes. The first one is the far-field staged laser accelerator, STELLA, which is under exploration at the ATF using a CO{sub 2} laser. The second is a laser wakefield accelerator where ps-TW CO{sub 2} lasers have a great potential. Inverse to the laser accelerator, a prospective monochromatic x-ray source feasible at the ATF will also utilize a 50 MeV subpicosecond electron beam and the first ps-TW CO{sub 2} laser, PITER I.

  5. Role of insulin receptor and insulin signaling on αPS2CβPS integrins' lateral diffusion.

    Science.gov (United States)

    Mainali, Dipak; Syed, Aleem; Arora, Neha; Smith, Emily A

    2014-12-01

    Integrins are ubiquitous transmembrane receptors with adhesion and signaling properties. The influence of insulin receptor and insulin signaling on αPS2CβPS integrins' lateral diffusion was studied using single particle tracking in S2 cells before and after reducing the insulin receptor expression or insulin stimulation. Insulin signaling was monitored by Western blotting for phospho-Akt expression. The expression of the insulin receptor was reduced using RNA interference (RNAi). After insulin receptor RNAi, four significant changes were measured in integrin diffusion properties: (1) there was a 24% increase in the mobile integrin population, (2) 14% of the increase was represented by integrins with Brownian diffusion, (3) for integrins that reside in confined zones of diffusion, there was a 45% increase in the diameter of the confined zone, and (4) there was a 29% increase in the duration integrins spend in confined zones of diffusion. In contrast to reduced expression of the insulin receptor, which alters integrin diffusion properties, insulin stimulation alone or insulin stimulation under conditions of reduced insulin receptor expression have minimal effects on altering the measured integrin diffusion properties. The differences in integrin diffusion measured after insulin receptor RNAi in the presence or absence of insulin stimulation may be the result of other insulin signaling pathways that are activated at reduced insulin receptor conditions. No change in the average integrin diffusion coefficient was measured for any conditions included in this study.

  6. PS overcomes two serious magnet failures

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    Two magnets and a bus bar connection in the PS were found to be faulty during high-voltage tests at the end of the accelerator shutdown. A five-week repair schedule was quickly devised. A team of mechanics, technicians and engineers worked at full speed to replace the faulty magnets, succeeding in limiting the delay of the accelerators' spring start-up to two weeks. These pictures show one of the magnets (no. 19) on the PS locomotive brought back into service for the removal and replacement operations.

  7. High voltage variable diameter insulator

    Science.gov (United States)

    Vanecek, David L.; Pike, Chester D.

    1984-01-01

    A high voltage feedthrough assembly (10) having a tubular insulator (15) extending between the ground plane ring (16) and the high voltage ring (30). The insulator (15) is made of Pyrex and decreases in diameter from the ground plane ring (16) to the high voltage ring (30), producing equipotential lines almost perpendicular to the wall (27) of the insulator (15) to optimize the voltage-holding capability of the feedthrough assembly (10).

  8. Positron Annihilation in the Bipositronium Ps2

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, David H.; Frolov, Alexei M.

    2005-07-01

    The electron-positron-pair annihilation in the bipositronium PS2 is considered. In particular, the two-, three-, one- and zero-photon annihilation rates are determined to high accuracy. The corresponding analytical expressions are also presented. Also, a large number of bound state properties have been determined for this system.

  9. The 4 Ps as a Guiding Perspective

    Science.gov (United States)

    Kalsbeek, David H.

    2013-01-01

    A 4 Ps perspective addresses immediate needs: to help institutions gain traction in their retention strategies by framing and reframing the challenges and the possible responses, by challenging some of the traditional mental models about retention that can distract or dilute those strategies, and by offering focus and coherence to institutional…

  10. 10th Anniversary P.S.

    CERN Multimedia

    Adams,J

    1969-01-01

    John Adams parle de la préhistoire du P.S. avec présentation des dias. Le DG B.Gregory prend la parole. Les organisateurs présentent sous la direction du "Prof.Ocktette"(?) un sketch très humoristique (p.e.existence de Quark etc.....)

  11. Back to work for the PS

    CERN Multimedia

    2006-01-01

    On 22 June, the PS's rotating machine started turning again for the first time since its enforced shutdown one month ago (see Bulletin No. 23-24/2006) - and the PS was back in operation the very next day! A team from Siemens worked their socks off, 6 days a week for one month (including public holidays), to repair the electrical power supply in collaboration with the AB/PO Group's Main Power Converters (MPC) Section. The generator's faulty rotor was dismantled and replaced by the renovated spare rotor. The multitude of electrical and mechanical connections together with the sheer weight of the rotor (80 tonnes) made this an extremely complex job. The AB/PO Group used the shutdown to test a back-up solution for the PS power supply. The accelerator was directly wired up to the 18 kV electrical network via a 13 MVA transformer, installed at the end of the 1970s but never used. This solution succeeded in bringing the PS back into operation but at limited energy and frequency. Just 14 GeV could be achieved, whic...

  12. Improved utilization of small-diameter ponderosa pine in glulam timber

    Science.gov (United States)

    Roland Hernandez; David W. Green; David E. Kretschmann; Steven P. Verrill

    2005-01-01

    This study involved the evaluation of ponderosa pine glulam made from lumber that was sawn from a small-diameter timber resource. Two different glulam beam depths were evaluated: 8 and 13 laminations. A comprehensive glulam test program was conducted to evaluate edgewise and flat-wise bending, shear, and tensile strength. Beam deflection was measured and a variety of...

  13. PS overcomes two serious magnet failures

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    Two magnets (no.'s 6 and 19)and a bus bar connection in the PS were found to be faulty during high-voltage tests at the end of the accelerator shutdown. A five-week repair schedule was quickly devised. A team of mechanics, technicians and engineers worked at full speed to replace the faulty magnets, succeeding in limiting the delay of the accelerators' spring start-up to two weeks. Pictured here are members of the PS team with the replacement no. 6 magnet. From left to right: In the back row, Frédéric Roussel (Transport DBS), Yves Bernard (Transport DBS), Luc Moreno (Cegelec), Thierry Battimanza (Transport DBS), Raymond Brown (AB/ABP), Thomas Zickler (AT/MEL); at the front, Steven Southern (AT/VAC), Thierry Gaidon (Brun & Sorensen), Philippe Vidales (Cegelec), Daniel Aubert (Cegelec), Jerome Cachet (Transport DBS), Jose Manual Gomes de Faria (AT/MEL), Eric Page (AT/VAC).

  14. PS overcomes two serious magnet failures

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    Two magnets and a bus bar connection in the PS were found to be faulty during high-voltage tests at the end of the accelerator shutdown. A five-week repair schedule was quickly devised. A team of mechanics, technicians and engineers worked at full speed to replace the faulty magnets, succeeding in limiting the delay of the accelerators´ spring start-up to two weeks. Here we see one of the replacement magnets (no. 19) being prepared.

  15. The PS overcomes two serious magnet failures

    CERN Multimedia

    2003-01-01

    Two magnets and a bus bar connection in the PS were found to be faulty during high-voltage tests at the end of the accelerator shutdown. A five-week repair schedule was quickly devised. A team of mechanics, technicians and engineers worked at full speed to replace the faulty magnets, succeeding in limiting the delay of the accelerators' spring start-up to two weeks.

  16. Motor-Generator Set, PS Main Supply

    CERN Multimedia

    CERN PhotoLab

    1983-01-01

    This is the "new" motor-generator set. It replaced the previous, original, one which had served from the PS start-up in 1959. Ordered in 1965, installed in 1967, it was brought into operation at the beginning of 1968. Regularly serviced and fitted with modern regulation and controls, it still serves at the time of writing (2006) and promises to serve for several more years, as a very much alive museum-piece. See also 6803016 and 0201010.

  17. Memories of the PS and of LEP

    CERN Document Server

    Steinberger, Jack

    2012-01-01

    The CERN PS, which started in 1959, and the Brookhaven AGS in 1960, represented an advance by a factor of more than five in the energy of proton accelerators, from the 5 GeV of the Berkeley Bevatron to about 30 GeV. These accelerators made possible the large progress in our understanding of particles and their interactions over the next two decades, culminating in the electroweak and QCD gauge theories.

  18. PS overcomes two serious magnet failures

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    Two magnets and a bus bar connection in the PS were found to be faulty during high-voltage tests at the end of the accelerator shutdown. A five-week repair schedule was quickly devised. A team of mechanics, technicians and engineers worked at full speed to replace the faulty magnets, succeeding in limiting the delay of the accelerators' spring start-up to two weeks. Here we see one of the replacement magnets (no. 6) being prepared.

  19. Transverse Mode Coupling Instability Measurements at Transition Crossing in the CERN PS

    CERN Document Server

    Aumon, S; Freyermuth, P; Gilardoni, S; Metral, E; Rumolo, G; Salvant, B; Steerenberg, R

    2010-01-01

    Transition crossing in the CERN PS is critical for the stability of high intensity beams, even with the use of a second order gamma jump scheme. The intense single bunch beam used for the neutron Time-of-Flight facility (n-ToF) needs a controlled longitudinal emittance blowup at flat bottom to prevent a fast single-bunch vertical instability from developing near transition. This instability is believed to be of Transverse Mode Coupling (TMCI) type. A series of measurements taken throughout 2009 and 2010 aim at using this TMCI observed on the ToF beam at transition, as a tool for estimating the transverse global impedance of the PS. For this purpose, we compare the measurement results with the predictions of the HEADTAIL code and find the matching parameters. This procedure also allows a better understanding of the differentmechanisms involved and can suggest how to improve the gamma jump scheme for a possible intensity upgrade of the n-ToF beam.

  20. Design of Injection and Extraction Systems with Optimisation of Lattice and Layout for the CERN PS2 Synchrotron

    CERN Document Server

    Bartmann, W

    2009-01-01

    The CERN Proton Synchrotron PS2 is one of the foreseen accelerators for the LHC injector upgrade. This upgrade aims first at increasing the instantaneous luminosity of LHC and second at providing a reliable beam for the CERN accelerator complex. From this aspect, the main characteristics of the PS2 are high reliability for high intensity beams. The goal of this thesis was the design of the machine’s lattice and injection/extraction systems meeting the constraints coming mainly from the LHC beam type but also from beam requirements of experiments at PS2 and the SPS. In the design, the given energy range together with filling schemes for different beam types and RF cogging were first used to define the circumference of the machine. Estimates on the space requirements of injection/extraction systems were made in order to divide the total machine length between arc and long straight section. Existing tunnels for transfer lines together with the minimisation of the total transfer line length favoured a race trac...

  1. Psühhodramaatikud annavad Pärnus eksami

    Index Scriptorium Estoniae

    2008-01-01

    29. maist kuni 1. juunini kestab Pärnus psühhodraama konverents "Geeniuste kohtumine", kus rahvusvahelise koolituse läbinud annavad eksami. Ruuda Palmquist on psühhodraama kui teadusharu rajajaid Eestis. Pärnus on kohal Rootsi Moreno Instituudi juhataja, psühhodraama lavastaja Marc Treadwell

  2. Observation of emittance growth at KEK PS

    CERN Document Server

    Igarashi, S; Nakamura, E; Shimosaki, Y; Shirakata, M; Takayama, K; Toyama, T

    2003-01-01

    Emittance growth has been observed in the transverse direction at the injection period of the 12 GeV main ring of the KEK proton synchrotron. Measurement of the beam profiles using flying wires has revealed a characteristic temporal change of the beam profile within a few milliseconds after injection. Horizontal emittance growth was observed when the horizontal tune was close to the integer. The effect was more enhanced for higher beam intensity and could not be explained with the injection mismatch. Resonance created by the space charge field was the cause of the emittance growth. A multiparticle tracking simulation program, ACCSIM, taking account of space charge effects has qualitatively reproduced the beam profiles.

  3. Psychometric properties of the French translation of the reduced KOOS and HOOS (KOOS-PS and HOOS-PS)

    DEFF Research Database (Denmark)

    Ornetti, P; Perruccio, A V; Roos, E M

    2009-01-01

    OBJECTIVE: To evaluate the psychometric properties of the French KOOS physical function (KOOS-PS) and HOOS physical function (HOOS-PS), specifically its feasibility, reliability, construct validity, and responsiveness. METHODS: Consecutive outpatients consulting for primary knee or hip osteoarthr......OBJECTIVE: To evaluate the psychometric properties of the French KOOS physical function (KOOS-PS) and HOOS physical function (HOOS-PS), specifically its feasibility, reliability, construct validity, and responsiveness. METHODS: Consecutive outpatients consulting for primary knee or hip...

  4. Sub-10 nm Silicon Nanopillar Fabrication Using Fast and Brushless Thermal Assembly of PS-b-PDMS Diblock Copolymer.

    Science.gov (United States)

    Garnier, Jérôme; Arias-Zapata, Javier; Marconot, Olivier; Arnaud, Sandrine; Böhme, Sophie; Girardot, Cécile; Buttard, Denis; Zelsmann, Marc

    2016-04-20

    A new approach to obtaining spherical nanodomains using polystyrene-block-polydimethylsiloxane (PS-b-PDMS) is proposed. To reduce drastically the process time, we blended a copolymer with cylindrical morphology with a PS homopolymer. Adding PS homopolymer into a low-molar-mass cylindrical morphology PS-b-PDMS system drives it toward a spherical morphology. Besides, by controlling the as-spun state, spherical PDMS nanodomains could be kept and thermally arranged. This PS-homopolymer addition allows not only an efficient, purely thermal arrangement process of spheres but also the ability to work directly on nontreated silicon substrates. Indeed, as shown by STEM measurements, no PS brush surface treatment was necessary in our study to avoid a PDMS wetting layer at the interface with the Si substrate. Our approach was compared to a sphere-forming diblock copolymer, which needs a longer thermal annealing. Furthermore, GISAXS measurements provided complete information on PDMS sphere features. Excellent long-range order spherical microdomains were therefore produced on flat surfaces and inside graphoepitaxy trenches with a period of 21 nm, as were in-plane spheres with a diameter of 8 nm with a 15 min thermal annealing. Finally, direct plasma-etching transfer into the silicon substrate was demonstrated, and 20 nm high silicon nanopillars were obtained, which are very promising results for various nanopatterning applications.

  5. Evolving science enhanced with iPS

    Directory of Open Access Journals (Sweden)

    Editor

    2007-11-01

    Full Text Available Dear friends, Greetings from all in the team. With the stage set for online submissions and the review-response-revision-resubmission process standardized, we have come with the first regular issue and from now there will be quarterly issues of the journal. Since the starting of the JSRM in a short span there have been a lot of developments, which we would rather say as "evolutions" keeping in mind, the recent iPS! This evolution we would like you to see from a background of the various developments in the art and science of medicine throughout in the past three centuries. We have come across the era of investigative tools such as bamboo made laryngoscopes to era of vaccines and antibiotics followed by the era of revolutionary non-invasive procedures and recently the nano technology based drugs and now the iPS! Macro to Micro, but still more to go. All through the influence of the society, religions, philosophies have been playing a very important role in every step the science of biology moves ahead. Starting with the contraception, assisted reproduction then the gene modified plants....and now the embryonic stem cells! With the advent of the iPS, though the issues of oncogenes, teratoma yet to be ruled out, we have found there is a way which can bypass the ES cells! Hats off to those scientists who have burnt their midnight oil to have found this way out! The lesson we learn is to explore things with an open mind and continue to proceed further without spending much time fingers crossed. Yours sincerely,The Editorial team.

  6. 7 CFR 51.2656 - Diameter.

    Science.gov (United States)

    2010-01-01

    ... Standards for Grades for Sweet Cherries 1 Definitions § 51.2656 Diameter. Diameter means the greatest dimension measured at right angles to a line from the stem to the blossom end of the cherry. ...

  7. The new low frequency accelerating systems for the CERN PS booster

    CERN Document Server

    Krusche, A

    1998-01-01

    A set of four, ferrite-loaded, low-frequency RF cavities equipped with local RF feedback has been built and installed in the CERN PS Booster rings. Together with the modified existing RF systems they now serve for acceleration as well as RF gymnastics of protons and heavy ions up to the highest beam intensities. The systems specifications with a frequency range of about 0.6 to 1.8 MHz and a nomina l RF peak voltage of 8 kV satisfy specifically the requirements of acceleration on harmonic 1 of the future proton beam for the LHC. The system design has been guided by the request for safety margins for high beam intensity operation and ease of maintenance and repair. Some design aspects are presented as well as the performance achieved.

  8. Chemotherapy and quality of life in NSCLC PS 2 patients

    DEFF Research Database (Denmark)

    Helbekkmo, Nina; Strøm, Hans H; Sundstrøm, Stein H

    2009-01-01

    INTRODUCTION: Nearly 40% of patients with advanced NSCLC are in performance status (PS) 2. These patients have a shorter life expectancy than PS 0/1 patients and they are underrepresented in clinical trials. Data on how platinum-based combination chemotherapy affects Health Related Quality of Life...... (HRQOL) of patients with PS 2 are scarce and the treatment of this important group of patients is controversial. METHODS: A national multicenter phase III study on platinum based chemotherapy to 432 advanced NSCLC patients included 123 patients with PS 2. To explore the treatment impact on HRQOL......: Whereas the demographic data at baseline were well balanced between the groups, the PS 2 patients had significantly worse function and more severe symptoms than the PS 0/1 patients. In response to combination chemotherapy, the PS 2 patients had a more profound improvement of global QOL, cognitive function...

  9. Height - Diameter predictive equations for Rubber (Hevea ...

    African Journals Online (AJOL)

    BUKOLA

    ABSTRACT. The importance of calibrating models on height-diameter relationship can never be over emphasized in predicting mean total height for trees when only diameter at breast height is measured traditionally. This study has evaluated a set of height-diameter models from twenty plots of Hevea brasilliensis plantation ...

  10. Sofrimento psíquico e trabalho

    Directory of Open Access Journals (Sweden)

    Sarah Rosa Salles Vieira

    2014-03-01

    Full Text Available O presente artigo aprofunda questões clínico-téoricas relacionadas especificamente ao trabalho docente e ao sofrimento psíquico a ele relacionado a partir da observação clínica e vivência grupal nos atendimentos terapêuticos ocupacionais realizados no Hospital do Servidor Público Estadual de São Paulo "Francisco Morato de Oliveira" (HSPE-FMO. Partindo dos estudos acerca da Psicopatologia do Trabalho de Christophe Dejours, do trabalho docente e do relato de um caso clínico, caracteriza a problemática do sofrimento no trabalho, os sistemas de defesa contra este sofrimento, a ameaça à subjetividade do próprio trabalhador, as representações e conflitos vivenciados no trabalho docente, bem como a relação aditiva estabelecida como uma estratégia inconsciente de sobrevivência psíquica.

  11. The (7,7) optics at CERN PS

    CERN Document Server

    Serluca, M; Efthymiopoulos, I; Sperati, F; Sterbini, G; Tecker, F; Zisopoulos, P

    2017-01-01

    The PS lattice is composed by one hundred combinedfunction magnets, which set the bare tune of the machineto (Qh,Qv) = (6.25, 6.28). Low energy quadrupoles areused at injection to move the tune in a limited working pointarea. In particular the vertical tune is moved below 6.25 toavoid the structural resonance 8Qv= 50 coupled with spacecharge, which leads to strong losses. In view of the highdemands in terms of beam brightness for LIU and HL-LHCprojects, the interest of exploring different integer tune work-ing area started during last years. During 2016, for the firsttime, it has been possible to explore the (7,7) tune workingarea at injection using the auxiliary circuits of the combinedfunction magnets. A finite-element magnetic model, underdevelopment, has been used to predict the required currentsin order to get the desired optical parameters. In this pa-per we present the results and issues encountered duringthe Machine Development (MD) studies about the injectionin the (7,7) area along with optics and be...

  12. KAJIAN INDUCED PLURIPOTENT STEMCELL (iPS (HARAPAN DAN TANTANGAN

    Directory of Open Access Journals (Sweden)

    Masagus Zainuri

    2014-05-01

    Full Text Available AbstractInduced Pluripotent Stemcell (iPS are adult cells which the genetic information in the nucleus of those cells being reprogrammed (reprogram by inserting exogenous pluripotential genes. The exogenous gene transduction is using vectors, such as lentivirus, retrovirus, or adenovirus, which suppressed the gene expression of the original cells, so they will express the transduced exogenous gene. Viral vectors are then used to reprogramming and producing iPS clones that are pluripotent. iPS derived from adult cells of patient with certain diseases will be used as a tool to study the mechanisms of those specific diseases and the effects of selected drugs against the diseases. Several previous studies have shown that iPS clones developed from specific genetic disease have its original genotype and retain the character of the response to the drug that similar as the original adult cells. Opportunities for the utilization of autologous iPS cell therapy in the future is wide open as expected iPS transplant will not be rejected when transplanted back to the patient. Behind all its potential, iPS production is still facing some problems to be applicable clinically. The use of viruses as vectors may cause problems due to virus gene sequences may be integrated into the genome of the DNA donor cell, thereby causing mutations of the iPS clones. Several subsequent studies have succeeded in replacing the use of viruses as vectors, but the level of efficiency obtained is still very low. Another problem that arises is that epigenetic changes may occur in iPS cultures. Many advanced research related to iPS may be developed in Indonesia and is necessary to improve the production efficiency of iPS and solve iPS clones epigenetic changes problems in the future.Keywords: iPS, pluripotency, transduction, transfection.AbstrakInduced Pluripotent Stemcell (iPS adalah sel somatic dewasa yang informasi genetika dalam inti selnyadiprogram ulang (reprogram dengan cara

  13. Comparison of molecular species of various transphosphatidylated phosphatidylserine (PS) with bovine cortex PS by mass spectrometry

    NARCIS (Netherlands)

    Chen, S.; Li, K.W.

    2008-01-01

    The exogenous introduction of a molecular species mixture of bovine cortex phosphatidylserine (BC-PS) has been claimed to improve memory function in subjects suffering from age-associated memory impairment and dementia. However, it has been also reported that oral administration of another molecular

  14. A Comparative Study of Fast Wire Scanners, Beamscope and SEM-Grids for Emittance Measurements in the PS Booster

    CERN Document Server

    Arruat, M; Jansson, A; Lindroos, M; Martini, M; Olsfors, J; Raich, U; Schönauer, Horst Otto

    1997-01-01

    The tight emittance budget, imposed on the production of the high-brilliance beams in the LHC preinjectors, demands the elimination of all possible sources of beam blow-up. A prerequisite for this is reliable instrumentation and evaluation methods for comparison of their data. We have made a study of three methods for emittance measurement in the PS Booster: fast wire-scanners, BeamScope, and SEM-grids in a measurement line. For the fast wire-scanners, a full Monte-Carlo simulation was made of the beam-wire interaction, for an energy range from 100 MeV to 1 GeV, and compared to measured values. Data from a scraping method (BeamScope) are compared to profile measurements, using Abel-type integral transformations. Results will be presented.

  15. Design and Tests of a Low-Loss Multi-Turn Ejector for the CERN PS

    CERN Document Server

    Giovannozzi, Massimo

    2006-01-01

    Following the positive results of a three-year measurement campaign at the CERN Proton Synchrotron, a study of a possible implementation of the proposed Multi-Turn Extraction (MTE) based on beam splitting with stable islands in the transverse phase space was undertaken. A substantial reduction of beam losses, with respect to the present extraction scheme, could be achieved with the proposed technique when delivering the high-intensity proton beams required for the planned CERN Neutrino to Gran Sasso Project. Major modifications to the ring layout are needed, such as a new design of the extraction bumps including also the installation of three additional kickers to create a closed-bump over the five turns used to extract the split beam. The ring aperture was reviewed and improvements are proposed to reduce possible beam losses between beam splitting and extraction. The goal is to implement the proposed changes by beginning of 2008 and to commission the novel extraction during the 2008 PS physics run.

  16. LS1 Report: first beams in the Booster

    CERN Multimedia

    Anaïs Schaeffer

    2014-01-01

    On Monday, 2 June, the Operations Group injected the first beams into the PS Booster (PSB). The PSB, the second machine in the LHC injector chain to be recommissioned (Linac2 was the first), also provides beams for non-LHC experiments, some of which will need beams for physics as early as this summer.   The PS Booster. The Operations Group has been back in control of the PS Booster for a month now, having taken over where the engineers and experts of the EN Department, who were responsible for the maintenance work, left off. The group first ran tests with no beam (known as “cold check-out”) to check and requalify all the machine instrumentation, from the control room to the ring itself. Now in beam mode, the Booster is being prepared both to begin supplying the PS at the end of June and, above all, for physics to restart in the ISOLDE experimental area. The PS Booster console in the CERN Control Centre. “We have around 15 types of beams to ‘prepa...

  17. Hybrid beams in the LHC

    CERN Multimedia

    CERN Bulletin

    2011-01-01

    The first proton-ion beams were successfully circulated in the LHC a couple of weeks ago. Everything went so smoothly that the LHC teams had planned the first p-Pb collisions for Wednesday, 16 November. Unfortunately, a last-minute problem with a component of the PS required for proton acceleration prevented the LHC teams from making these new collisions. However, the way is open for a possible physics run with proton-lead collisions in 2012.   Members of the LHC team photographed when the first hybrid beams got to full energy. The proton and lead beams are visible on the leftmost screen up on the wall (click to enlarge the photo). The technical challenge of making different beams circulate in the LHC is by no means trivial. Even if the machine is the same, there are a number of differences when it is operated with beams of protons, beams of lead or beams of proton and lead. Provided that the beams are equal, irrespective of whether they consist of protons or lead nuclei, they revolve at the...

  18. Studies of a Target System for a 4-MW, 24-GeV Proton Beam

    CERN Multimedia

    2002-01-01

    We propose to perform a proof-of-principle test of a target station suitable for a Neutrino Factory or Muon Collider source using a 24-GeV proton beam incident on a target consisting of a free mercury jet that is inside a 15- T capture solenoid magnet. This test could be performed in the TT2A tunnel of the nTOF proton line (upstream of the spallation target). The tests would require only $\\approx$ 100 fast-extracted pulses of full PS intensity, delivered in a pulse-on-demand mode of operation over about 2 weeks. The main piece of apparatus is the LN2-precooled, 15- T copper magnet of total volume slightly over 1 m$^{3}$ with a 15-cm-diameter warm bore. The principle diagnostic is a high-speed optical camera. The mercury jet is part of a closed mercury loop that includes an insert into the bore of the magnet.

  19. Beam line from straight-section 16

    CERN Multimedia

    CERN PhotoLab

    1971-01-01

    The start of a long trail. The beam line from straight-section 16, where protons are fast ejected, is seen at the point where it crosses the Linac shielding wall as it leaves the PS en route to the ISR.

  20. Comparison between electron cloud build-up measurements and simulations at the CERN PS

    CERN Document Server

    Caspers, F; Mahner, E; Rumolo, G; Yin Vallgren, C; Iadarola, G

    2012-01-01

    The build up of an Electron Cloud (EC) has been observed at the CERN Proton Synchrotron (PS) during the last stages of the LHC high intensity beam preparation, especially after the bunch shortening before extraction. Two dedicated EC experiments, both equipped with two button pick-ups, a pressure gauge, a clearing electrode and a small dipole magnet, are available in two straight sections of the machine. A measurement campaign has been carried out, in order to scan the EC build-up of LHC-type beams with different bunch spacing, bunch intensity and bunch length. Such information, combined with the results from build up simulations, is of relevance for the characterization in terms of Secondary Emission Yield (SEY) of the chamber inner surface. The interest is twofold: this will enable us to predict the EC build up distribution in the PS for higher intensity beams in the frame of the upgrade program, and it will provide validation of the EC simulation models and codes.

  1. Silicon microfabricated beam expander

    Energy Technology Data Exchange (ETDEWEB)

    Othman, A., E-mail: aliman@ppinang.uitm.edu.my; Ibrahim, M. N.; Hamzah, I. H.; Sulaiman, A. A. [Faculty of Electrical Engineering, Universiti Teknologi MARA Malaysia, 40450, Shah Alam, Selangor (Malaysia); Ain, M. F. [School of Electrical and Electronic Engineering, Engineering Campus, Universiti Sains Malaysia, Seri Ampangan, 14300,Nibong Tebal, Pulau Pinang (Malaysia)

    2015-03-30

    The feasibility design and development methods of silicon microfabricated beam expander are described. Silicon bulk micromachining fabrication technology is used in producing features of the structure. A high-precision complex 3-D shape of the expander can be formed by exploiting the predictable anisotropic wet etching characteristics of single-crystal silicon in aqueous Potassium-Hydroxide (KOH) solution. The beam-expander consist of two elements, a micromachined silicon reflector chamber and micro-Fresnel zone plate. The micro-Fresnel element is patterned using lithographic methods. The reflector chamber element has a depth of 40 µm, a diameter of 15 mm and gold-coated surfaces. The impact on the depth, diameter of the chamber and absorption for improved performance are discussed.

  2. Electron beam machining using rotating and shaped beam power distribution

    Science.gov (United States)

    Elmer, J.W.; O`Brien, D.W.

    1996-07-09

    An apparatus and method are disclosed for electron beam (EB) machining (drilling, cutting and welding) that uses conventional EB guns, power supplies, and welding machine technology without the need for fast bias pulsing technology. The invention involves a magnetic lensing (EB optics) system and electronic controls to: (1) concurrently bend, focus, shape, scan, and rotate the beam to protect the EB gun and to create a desired effective power-density distribution, and (2) rotate or scan this shaped beam in a controlled way. The shaped beam power-density distribution can be measured using a tomographic imaging system. For example, the EB apparatus of this invention has the ability to drill holes in metal having a diameter up to 1,000 {micro}m (1 mm or larger), compared to the 250 {micro}m diameter of laser drilling. 5 figs.

  3. Electron beam machining using rotating and shaped beam power distribution

    Science.gov (United States)

    Elmer, John W.; O'Brien, Dennis W.

    1996-01-01

    An apparatus and method for electron beam (EB) machining (drilling, cutting and welding) that uses conventional EB guns, power supplies, and welding machine technology without the need for fast bias pulsing technology. The invention involves a magnetic lensing (EB optics) system and electronic controls to: 1) concurrently bend, focus, shape, scan, and rotate the beam to protect the EB gun and to create a desired effective power-density distribution, and 2) rotate or scan this shaped beam in a controlled way. The shaped beam power-density distribution can be measured using a tomographic imaging system. For example, the EB apparatus of this invention has the ability to drill holes in metal having a diameter up to 1000 .mu.m (1 mm or larger), compared to the 250 .mu.m diameter of laser drilling.

  4. PS main supply: motor-generator set.

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    In picture 04 the motor is on the right in the background and the main view is of the generator. The peak power in each PS cycle drawn from the generator, up to 96 MW, is taken from the rotational kinetic energy of the rotor (a heavy-weight of 80 tons), which makes the rotational speed drop by only a few percent. The motor replenishes the average power of 2 to 4 MW. Photo 05: The motor-generator set is serviced every year and, in particular, bearings and slip-rings are carefully checked. To the left is the motor with its slip-rings visible. It has been detached from the axle and moved to the side, so that the rotor can be removed from the huge generator, looming at the right.

  5. Feasibility Study of a Neutron Time Of Flight Facility at the CERN-PS

    CERN Document Server

    Andriamonje, Samuel A; Zanolli, M; Buono, S; Buttkus, J; Cennini, E; Cennini, P; Daems, G; Delaprison, J; Dobers, T; Dupont, M; Durieu, L; Ferrari, A; Giovannozzi, Massimo; Jacot, C; Magnin, R; Mahner, E; Métral, G; Pavlopoulos, P; Raich, U; Silari, Marco; Vlachoudis, V; Wilhelmsson, M

    1998-01-01

    This report summarises the feasibility study of a neutron time-of-flight facility at the CERN-PS as described in Refs. [1] and [2]. The idea is to extract at 24 GeV/cproton bunches (r.m.s. length ~7 ns) on to a target. The neutrons produced by spallation are directed to an experimental area located 230 m downstream throughout a vacuum pipe (diameter ~80 cm) making use of the existing TT2A tunnel about 7 m below the ISR tunnel

  6. GAUSSIAN BEAM LASER RESONATOR PROGRAM

    Science.gov (United States)

    Cross, P. L.

    1994-01-01

    In designing a laser cavity, the laser engineer is frequently concerned with more than the stability of the resonator. Other considerations include the size of the beam at various optical surfaces within the resonator or the performance of intracavity line-narrowing or other optical elements. Laser resonators obey the laws of Gaussian beam propagation, not geometric optics. The Gaussian Beam Laser Resonator Program models laser resonators using Gaussian ray trace techniques. It can be used to determine the propagation of radiation through laser resonators. The algorithm used in the Gaussian Beam Resonator program has three major components. First, the ray transfer matrix for the laser resonator must be calculated. Next calculations of the initial beam parameters, specifically, the beam stability, the beam waist size and location for the resonator input element, and the wavefront curvature and beam radius at the input surface to the first resonator element are performed. Finally the propagation of the beam through the optical elements is computed. The optical elements can be modeled as parallel plates, lenses, mirrors, dummy surfaces, or Gradient Index (GRIN) lenses. A Gradient Index lens is a good approximation of a laser rod operating under a thermal load. The optical system may contain up to 50 elements. In addition to the internal beam elements the optical system may contain elements external to the resonator. The Gaussian Beam Resonator program was written in Microsoft FORTRAN (Version 4.01). It was developed for the IBM PS/2 80-071 microcomputer and has been implemented on an IBM PC compatible under MS DOS 3.21. The program was developed in 1988 and requires approximately 95K bytes to operate.

  7. Method of automatic measurement and focus of an electron beam and apparatus therefor

    Science.gov (United States)

    Giedt, Warren H.; Campiotti, Richard

    1996-01-01

    An electron beam focusing system, including a plural slit-type Faraday beam trap, for measuring the diameter of an electron beam and automatically focusing the beam for welding. Beam size is determined from profiles of the current measured as the beam is swept over at least two narrow slits of the beam trap. An automated procedure changes the focus coil current until the focal point location is just below a workpiece surface. A parabolic equation is fitted to the calculated beam sizes from which optimal focus coil current and optimal beam diameter are determined.

  8. Method of automatic measurement and focus of an electron beam and apparatus therefore

    Science.gov (United States)

    Giedt, W.H.; Campiotti, R.

    1996-01-09

    An electron beam focusing system, including a plural slit-type Faraday beam trap, for measuring the diameter of an electron beam and automatically focusing the beam for welding is disclosed. Beam size is determined from profiles of the current measured as the beam is swept over at least two narrow slits of the beam trap. An automated procedure changes the focus coil current until the focal point location is just below a workpiece surface. A parabolic equation is fitted to the calculated beam sizes from which optimal focus coil current and optimal beam diameter are determined. 12 figs.

  9. PS: A nonprocedural language with data types and modules

    Science.gov (United States)

    Gokhale, M. B.

    1986-01-01

    The Problem Specification (PS) nonprocedural language is a very high level language for algorithm specification. PS is suitable for nonprogrammers, who can specify a problem using mathematically-oriented equations; for expert programmers, who can prototype different versions of a software system for evaluation; and for those who wish to use specifications for portions (if not all) of a program. PS has data types and modules similar to Modula-2. The compiler generates C code. PS is first shown by example, and then efficiency issues in scheduling and code generation are discussed.

  10. Distinct iPS Cells Show Different Cardiac Differentiation Efficiency.

    Science.gov (United States)

    Ohno, Yohei; Yuasa, Shinsuke; Egashira, Toru; Seki, Tomohisa; Hashimoto, Hisayuki; Tohyama, Shugo; Saito, Yuki; Kunitomi, Akira; Shimoji, Kenichiro; Onizuka, Takeshi; Kageyama, Toshimi; Yae, Kojiro; Tanaka, Tomofumi; Kaneda, Ruri; Hattori, Fumiyuki; Murata, Mitsushige; Kimura, Kensuke; Fukuda, Keiichi

    2013-01-01

    Patient-specific induced pluripotent stem (iPS) cells can be generated by introducing transcription factors that are highly expressed in embryonic stem (ES) cells into somatic cells. This opens up new possibilities for cell transplantation-based regenerative medicine by overcoming the ethical issues and immunological problems associated with ES cells. Despite the development of various methods for the generation of iPS cells that have resulted in increased efficiency, safety, and general versatility, it remains unknown which types of iPS cells are suitable for clinical use. Therefore, the aims of the present study were to assess (1) the differentiation potential, time course, and efficiency of different types of iPS cell lines to differentiate into cardiomyocytes in vitro and (2) the properties of the iPS cell-derived cardiomyocytes. We found that high-quality iPS cells exhibited better cardiomyocyte differentiation in terms of the time course and efficiency of differentiation than low-quality iPS cells, which hardly ever differentiated into cardiomyocytes. Because of the different properties of the various iPS cell lines such as cardiac differentiation efficiency and potential safety hazards, newly established iPS cell lines must be characterized prior to their use in cardiac regenerative medicine.

  11. T8 Beam Parameters and π+π- pairs production on Pt foil

    CERN Document Server

    Afanasyiev, L; Drijard, D; Gortchakov, O; Nemenov, L; Pentia, M; Vrba, T; Yazkov, V

    2013-01-01

    The PS proton beam position and beam size in the T8 channel, incident on the DIRAC target and Pt foil, have been evaluated. The obtained parameters were used to evaluate the ratio between π+π- pairs produced by the beam halo and the π+π- pairs produced by A2π break-up in the Pt foil.

  12. AA, entrance of proton beam to antiproton production target

    CERN Multimedia

    CERN PhotoLab

    1980-01-01

    Please look up 8010295 first. The intense proton beam from the 26 GeV PS arrives from the right, through the vacuum chamber. The big flange contains a thin window, after which the proton beam continues through free air. A beam transformer, affixed to the shielding block, measures its intensity, before it enters the hole in the concrete to hit the target behind it.

  13. MERIT - The high intensity liquid mercury target experiment at the CERN PS

    CERN Document Server

    Efthymiopoulos, I

    2009-01-01

    The MERIT experiment is a proof-of-principle test of a target system for high power proton beams to be used as front-end for a Neutrino Factory complex or a Muon Collider. The experiment took data in autumn 2007 with the fast extracted beam from the CERN Proton Synchrotron (PS) to a maximum intensity of about 30 × 1012 protons per pulse. The target system, based on a free mercury jet, allowed investigation of the interseption of a 4-MW proton beam inside a 15-T magnetic field required to capture the low-energy secondary pions as the source of the required intense muon beams. Particle detectors have been installed around the target setup to measure the secondary particle flux out of the target and probe cavitation effects in the mercury jet when exited with a beam of variable intensity. With the analysis of the data ongoing, results will be presented here that demonstrate the validity of the liquid target concept.

  14. Determination of Beam Intensity and Position in a Particle Accelerator

    CERN Document Server

    Kasprowicz, Grzegorz

    2010-01-01

    The Proton Synchrotron accelerator (PS), installed at CERN, although commissioned in 1959, still plays a central role in the production of beams for the Antiproton Decelerator, Super Proton Synchrotron, various experimental areas and for the Large Hadron Collider (LHC). The PS produces beams of different types of particles, mainly protons, but also various species of ions. Almost all these particle beams pass through the PS. The quality of the beams delivered to the LHC has a direct impact on the effective luminosity, and therefore the performance of the instrumentation of the PS is of great importance. The old trajec- tory and orbit measurement system of the PS dated back to 1988 and no longer fulfilled present day requirements. It used 40 beam position monitors (BPMs) and an analogue signal processing chain to acquire the trajectory of one single particle bunch out of many, over two consecutive turns at a maximum rate of once every 5ms. The BPMs were in good condition, however the electronics was aging and ...

  15. LEADIR-PS: providing unprecedented SMR safety and economics

    Energy Technology Data Exchange (ETDEWEB)

    Hart, R.S., E-mail: N2i2@xplornet.ca [Northern Nuclear Industries Incorporated, Cambridge, ON (Canada)

    2015-07-01

    Northern Nuclear Industries Incorporated (N{sup 2} I{sup 2}) is developing Small Modular Reactors (SMRs) called LEADIR-PS, an acronym for LEAD-cooled Integral Reactor-Passively Safe. LEADIR-PS integrates proven technologies including TRISO fuel, Pebble Bed core and graphite moderator, with molten lead coolant in an integral pool type reactor configuration to achieve unprecedented safety and economics. Plants under development are LEADIR-PS30, producing 30 MWth, LEADIR-PS100 producing 100 MWth and LEADIR-PS300 producing 300 MWth that are focused on serving the energy demands of areas with a small electrical grid and/or process heat applications. A plant consisting of six LEADIR-PS300 reactor modules serving a common turbine-generator, called the LEADIR-PS Six-Pack, is focused on serving areas with higher energy demands and a robust electricity grid. The Gen{sup +} I LEADIR-PS plants are inherently/passively safe. There is no potential for a Loss Of Coolant Accident, a reactivity transient without shutdown, a loss of heat sink, or hydrogen generation. No active systems or operator actions are required to assure safety. The unprecedented safety of LEADIR-PS reactors avoids large exclusion radius and demanding evacuation plan requirements. LEADIR-PS, with steam conditions of 370 {sup o}C and 12 MPa can serve over 85% of the world's non-transportation process heat demands. In Canada, the electricity and process heat demands, ranging from those of remote communities and the oil sands to densely populated areas can be served by LEADIR-PS. (author)

  16. Gaussian-Beam/Physical-Optics Design Of Beam Waveguide

    Science.gov (United States)

    Veruttipong, Watt; Chen, Jacqueline C.; Bathker, Dan A.

    1993-01-01

    In iterative method of designing wideband beam-waveguide feed for paraboloidal-reflector antenna, Gaussian-beam approximation alternated with more nearly exact physical-optics analysis of diffraction. Includes curved and straight reflectors guiding radiation from feed horn to subreflector. For iterative design calculations, curved mirrors mathematically modeled as thin lenses. Each distance Li is combined length of two straight-line segments intersecting at one of flat mirrors. Method useful for designing beam-waveguide reflectors or mirrors required to have diameters approximately less than 30 wavelengths at one or more intended operating frequencies.

  17. 7 CFR 51.320 - Diameter.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... Standards for Grades of Apples Definitions § 51.320 Diameter. When measuring for minimum size, “diameter...

  18. Height - Diameter predictive equations for Rubber (Hevea ...

    African Journals Online (AJOL)

    BUKOLA

    Keywords: height-diameter equations, allometric models, predictive equations, sigmoidal curve. INTRODUCTION. Among pertinent tree characteristics for quantitative tree measurements and reasonable prediction are diameter at breast (dbh) and height. They proffer logistic data for modeling and futuristic prediction for ...

  19. Diameter preserving linear maps and isometries, II

    Indian Academy of Sciences (India)

    In this paper we study diameter preserving mappings on spaces of affine functions. Precisely, let S be a compact convex set in a locally convex Hausdorff space and let eЕSЖ be the space of all (real or complex) continuous affine functions on S. We are interested in linear bijections on eЕSЖ which preserve the diameter of ...

  20. Modulation of enzymatic PS synthesis by liposome membrane composition.

    Science.gov (United States)

    Pinsolle, Alexandre; Roy, Philippe; Cansell, Maud

    2014-03-01

    Phosphatidylserine (PS) is a phospholipid known to exert important physiological roles in humans. However, this phospholipid (PL) is poorly available as a natural source and hardly produced by the chemical route. In this work, PS was obtained by transphosphatidylation using phospholipase D (PLD) and PL self-assembled into liposomes as the substrates. The aim was to better understand how the liposome membrane composition could modulate PS yield. Three lecithins were used as PL substrates, one originated from a marine source providing a high amount of n-3 polyunsaturated fatty acids, and two issued from soya differing in their phosphatidylcholine (PC) content. Different parameters such as Ca(2+) content, enzyme and L-serine concentrations modulated PS synthesis. The presence of Ca(2+) increased PS conversion yield. The alcohol acceptor (L-serine) concentration positively acted on PL conversion, by governing the equilibrium between transphosphatidylation and hydrolysis. Beside these specific reaction conditions, it was demonstrated that the membrane composition of the liposomes modulated PS synthesis. A direct correlation between PS accumulation and the amount of cholesterol or α-tocopherol incorporated into the soya lecithins was observed. This result was interpreted in terms of "head" spacers promoting PLD transphosphatidylation. On the whole, this work provided key parameters for the formulation of liposomes using enzymatic PLD technology, to produce lecithins enriched in different proportions of PS and esterified with various types of fatty acids depending on the initial lecithin source. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Spectroscopic Classification of PS16chs with SOAR/Goodman

    Science.gov (United States)

    Miller, J. A.; Hounsell, R. A.; Pan, Y.-C.; Foley, R. J.; Jha, S. W.; Rest, A.; Scolnic, D.

    2016-05-01

    We report the classification of PS16chs from spectroscopic observation with the Goodman spectrograph on the SOAR telescope. The observation was made on 2016 May 08 UT. We classify PS16chs as a SN Ia near maximum light at z = 0.19.

  2. Motor-Generator powering the PS (Proton Synchrotron) main magnets

    CERN Multimedia

    1983-01-01

    This motor-generator,30 MW peak, 1500 r.p.m.,pulsed power supply for the PS main magnet replaced in 1968 the initial 3000 r.p.m. motor-generator-flywheel set which had served from the PS start-up in 1959 until end 1967. See also photo 8302337 and its abstract.

  3. Transfer line TT70 (electrons from PS to SPS)

    CERN Multimedia

    CERN PhotoLab

    1981-01-01

    As injectors for LEP, PS and SPS had to be converted to the acceleration of electrons and positrons. So far, only positively charged particles had been transferred from the PS to the SPS, for the negatively charged electrons a new transfer line, TT70, had to be built. Due to the difference in level of the two machines, the transfer line slopes and tilts.

  4. Psühhodraama - spontaansuse kool / Taimi Elenurm

    Index Scriptorium Estoniae

    Elenurm, Taimi

    2010-01-01

    Viinis ja New Yorgis tegutsenud psühhiaatri Jakob Levy Moreno loodud psühhodraamast, mis võimaldab rollimängu kaudu näha ennast läbi teiste silmade, aga ka vabaneda pingetest andes võimaluse käituda teisiti kui tavaelus

  5. Optical coating uniformity of 200mm (8") diameter precut wafers

    Science.gov (United States)

    Burt, Travis C.; Fisher, Mark; Brown, Dean; Troiani, David

    2017-02-01

    Automated spectroscopic profiling (mapping) of a 200 mm diameter near infrared high reflector (centered at 1064 nm) are presented. Spatial resolution at 5 mm or less was achieved using a 5 mm × 1.5 mm monochromatic beam. Reflection changes of 1.0% across the wafer diameter were observed under s-polarized and p- polarized conditions. Redundancy was established for each chord by re-measuring the center of the wafer and reproducibility of approximately used to measure the reflectance and transmittance of a sample across a range of angles (θi) at near normal angles of incidence (AOI). A recent development by Agilent Technologies, the Cary 7000 Universal Measurement Spectrophotometer (UMS) combines both reflection and transmission measurements from the same patch of a sample's surface in a single automated platform for angles of incidence in the range 5°use of MPS on the Cary 7000 UMS with rotational (Φ) and vertical (z) sample positioning control. MPS(θi,Φ,z) provides for automated unattended multi-angle R/T analysis of at 200 mm diameter samples with the goal to provide better spectroscopic measurement feedback into large wafer manufacturing to ensure yields are maximized, product quality is better controlled and waste is reduced before further down-stream processing.

  6. Beam Diagnostics

    CERN Document Server

    Raich, U

    2013-01-01

    As soon as the first particles emerge from an ion source, the source characteristics need to be determined. The total beam intensity, the transverse particle distributions, the beam divergence and emittance as well as the longitudinal parameters of the beam must be measured. This chapter provides an overview of typical measurement methods and the instruments used, and shows the results obtained.

  7. Successful online learning – the five Ps

    Directory of Open Access Journals (Sweden)

    Jim FLOOD

    2004-04-01

    Full Text Available Successful online learning – the five Ps Jim FLOOD E-learning Consultant-UK jimflood@btinternet.com Key learning points • An important aspect of design for online learning is visual ergonomics. • Learning theories offer poor predictive power in terms of how learners work and learn. • Success at learning is closely related to emotional engagement–and learning designers tend to ignore this aspect. • Online learning poses a challenging experience for learners–and they need support to cope with it. • A key goal to achieve Praxis – being able to put learning into practice. Many of you will be familiar with the three (or more Ps of marketing and even if not, as trainers or teachers you are likely to have used mnemonics as an aid to retention and recall. Mnemonics are especially useful when you need to get the key points to ‘stick’ in the minds of your audience. With this in mind I offer you the 5 Ps of online learning: Presentation, Pedagogy, Promotion, Preparation and Props. What I offer is not new; in fact much of it results from the eleven years of online teaching and learning at The Open University, the £22 million it has spent on research and evaluation 1, and the worldwide community that have been sharing experience in recent years. You can therefore consider these 5 Ps to be a convenient re-packing of the information and experience that can be found in abundance on the Internet. Presentation Good graphic design appeals to the subtle process by which the brain processes information and, as a result, we decide if we like the ‘look and feel’ of a visual environment. Part of liking this ‘look and feel’ is the way the text and pictorial layout can appear inviting and encouraging–a vital aspect of any online learning environment. Another aspect of presentation is how the text reads in terms of engaging the learner and introducing the story to be told–as well as being written in clear and concise English When browsing through books

  8. Femoral head diameter in the Malaysian population.

    Science.gov (United States)

    Lee, Chee Kean; Kwan, Mun Keong; Merican, Azhar Mahmood; Ng, Wuey Min; Saw, Lim Beng; Teh, Kok Kheng; Krishnan, Manoharan; Ramiah, Ramanathan

    2014-08-01

    Hip arthroplasty is commonly performed worldwide. The objective of this study was to determine the diameter of the femoral head in the Malaysian population in relation to gender and race (i.e. among Malay, Chinese and Indian patients). This was a retrospective cross-sectional study performed between January 1995 and December 2006, evaluating the femoral head diameters of all patients aged 50 years and above who underwent hemiarthroplasty at two major hospitals in Malaysia. A total of 945 femoral heads (663 women, 282 men) were evaluated. The mean age of the patients in our cohort was 75.2 ± 9.4 (range 50-101) years. The mean femoral head diameter (with intact articular cartilage) was 44.9 ± 3.2 (range 38-54) mm. In our study, men had a significantly larger mean femoral head diameter than women (47.7 ± 2.8 mm vs. 43.7 ± 2.4 mm; p Chinese ethnicity were also found to have significantly larger femoral head diameters, when compared among the three races studied (p Malaysians have a mean femoral head diameter of 44.9 ± 3.2 mm. Among our patients, Chinese patients had a significantly larger femoral head size than Malay and Indian patients. We also found that, in our cohort, men had significantly larger femoral head diameters than women.

  9. Telomere reprogramming and maintenance in porcine iPS cells.

    Directory of Open Access Journals (Sweden)

    Guangzhen Ji

    Full Text Available Telomere reprogramming and silencing of exogenous genes have been demonstrated in mouse and human induced pluripotent stem cells (iPS cells. Pigs have the potential to provide xenotransplant for humans, and to model and test human diseases. We investigated the telomere length and maintenance in porcine iPS cells generated and cultured under various conditions. Telomere lengths vary among different porcine iPS cell lines, some with telomere elongation and maintenance, and others telomere shortening. Porcine iPS cells with sufficient telomere length maintenance show the ability to differentiate in vivo by teratoma formation test. IPS cells with short or dysfunctional telomeres exhibit reduced ability to form teratomas. Moreover, insufficient telomerase and incomplete telomere reprogramming and/or maintenance link to sustained activation of exogenous genes in porcine iPS cells. In contrast, porcine iPS cells with reduced expression of exogenous genes or partial exogene silencing exhibit insufficient activation of endogenous pluripotent genes and telomerase genes, accompanied by telomere shortening with increasing passages. Moreover, telomere doublets, telomere sister chromatid exchanges and t-circles that presumably are involved in telomere lengthening by recombination also are found in porcine iPS cells. These data suggest that both telomerase-dependent and telomerase-independent mechanisms are involved in telomere reprogramming during induction and passages of porcine iPS cells, but these are insufficient, resulting in increased telomere damage and shortening, and chromosomal instability. Active exogenes might compensate for insufficient activation of endogenous genes and incomplete telomere reprogramming and maintenance of porcine iPS cells. Further understanding of telomere reprogramming and maintenance may help improve the quality of porcine iPS cells.

  10. Telomere reprogramming and maintenance in porcine iPS cells.

    Science.gov (United States)

    Ji, Guangzhen; Ruan, Weimin; Liu, Kai; Wang, Fang; Sakellariou, Despoina; Chen, Jijun; Yang, Yang; Okuka, Maja; Han, Jianyong; Liu, Zhonghua; Lai, Liangxue; Gagos, Sarantis; Xiao, Lei; Deng, Hongkui; Li, Ning; Liu, Lin

    2013-01-01

    Telomere reprogramming and silencing of exogenous genes have been demonstrated in mouse and human induced pluripotent stem cells (iPS cells). Pigs have the potential to provide xenotransplant for humans, and to model and test human diseases. We investigated the telomere length and maintenance in porcine iPS cells generated and cultured under various conditions. Telomere lengths vary among different porcine iPS cell lines, some with telomere elongation and maintenance, and others telomere shortening. Porcine iPS cells with sufficient telomere length maintenance show the ability to differentiate in vivo by teratoma formation test. IPS cells with short or dysfunctional telomeres exhibit reduced ability to form teratomas. Moreover, insufficient telomerase and incomplete telomere reprogramming and/or maintenance link to sustained activation of exogenous genes in porcine iPS cells. In contrast, porcine iPS cells with reduced expression of exogenous genes or partial exogene silencing exhibit insufficient activation of endogenous pluripotent genes and telomerase genes, accompanied by telomere shortening with increasing passages. Moreover, telomere doublets, telomere sister chromatid exchanges and t-circles that presumably are involved in telomere lengthening by recombination also are found in porcine iPS cells. These data suggest that both telomerase-dependent and telomerase-independent mechanisms are involved in telomere reprogramming during induction and passages of porcine iPS cells, but these are insufficient, resulting in increased telomere damage and shortening, and chromosomal instability. Active exogenes might compensate for insufficient activation of endogenous genes and incomplete telomere reprogramming and maintenance of porcine iPS cells. Further understanding of telomere reprogramming and maintenance may help improve the quality of porcine iPS cells.

  11. Beam line to S155

    CERN Multimedia

    1977-01-01

    The experiment S155 was designed by the Orsay (CSNM-CNRS) Collaboration to observe the properties of exotic light nuclei. It was installed in the PS neutrino tunnel. The photo shows a mass spectrometer (in the background) on line with the PS proton beam which arrives (bottom, right) from the fast extraction FE74. Roger Fergeau stands on the left. The alkaline isotopes produced in the carbon-uranium target heated at 2000°C were swiftly extracted, mass separated, and brought to a detector behind the shielding. Sodium 34 (11 protons and 23 neutrons) was observed and its half-life of only 5 ms was measured. The excited levels 2+ of Magnesium 30 and Magnesium 32 (Sodium descendants) were localised, and the magic number 20 was found to vanish. Thus, the discovery made earlier for Sodium 30 and Sodium 32, with the same apparatus, was confirmed. (See also photo 7706511.)

  12. Basic performance of a position-sensitive tissue-equivalent proportional chamber (PS-TEPC)

    Energy Technology Data Exchange (ETDEWEB)

    Kishimoto, Yuji, E-mail: yuji.kishimoto@kek.jp [High Energy Accelerator Research Organization (KEK) (Japan); Sasaki, Shinichi; Saito, Kiwamu; Takahashi, Kazutoshi [High Energy Accelerator Research Organization (KEK) (Japan); Doke, Tadayoshi [Waseda University (Japan); Miuchi, Kentaro [Kobe University (Japan); Fuse, Tetsuhito; Nagamatsu, Aiko [Japan Aerospace Exploration Agency (JAXA) (Japan); Uchihori, Yukio; Kitamura, Hisashi [National Institute of Radiological Sciences (Japan); Terasawa, Kazuhiro [Keio University (Japan); Japan Aerospace Exploration Agency (JAXA) (Japan)

    2013-12-21

    The characteristics and performance of the prototype of a Position-Sensitive Tissue-Equivalent Proportional Chamber (PS-TEPC), consisting of a miniaturized micro-pixel chamber (μ-PIC), were investigated. The gas–gain curve of the μ-PIC and an approximate function with which to convert measured collected charge into the primary charge ionized by incident heavy-ion particles were obtained. The measured Linear Energy Transfer (LET) indicated good agreement with that of the injected beam calculated using SRIM2008 code in the LET range from 0.4 to 180keV/μm, which roughly covers the whole LET range required for space dosimeters. As expected, the measured energy resolution improved with increasing LET of the injected beam. It was estimated to be 27% for 0.4keV/μm, which is just about the LET of minimum-ionizing particles. Consequently, it was confirmed that the PS-TEPC exhibits no significant undesirable feature but is well suited for space dosimetry.

  13. Appendiceal diameter: CT versus sonographic measurements

    Energy Technology Data Exchange (ETDEWEB)

    Orscheln, Emily S. [University of Cincinnati Medical Center, Department of Radiology, Cincinnati, OH (United States); Trout, Andrew T. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)

    2016-03-15

    Ultrasound and CT are the dominant imaging modalities for assessment of suspected pediatric appendicitis, and the most commonly applied diagnostic criterion for both modalities is appendiceal diameter. The classically described cut-off diameter for the diagnosis of appendicitis is 6 mm when using either imaging modality. To demonstrate the fallacy of using the same cut-off diameter for both CT and US in the diagnosis of appendicitis. We conducted a retrospective review of patients younger than 18 years who underwent both US and CT of the appendix within 24 h. The shortest transverse dimension of the appendix was measured at the level of the proximal, mid and distal appendix on US and CT images. We compared mean absolute difference in appendiceal diameter between US and CT, using the paired t-test. We reviewed exams of 155 children (58.7% female) with a mean age of 11.3 ± 4.2 years; 38 of the children (24.5%) were diagnosed with appendicitis. The average time interval between US and CT was 7.0 ± 5.4 h. Mean appendiceal diameter measured by CT was significantly larger than that measured by US in cases without appendicitis (5.3 ± 1.0 mm vs. 4.7 ± 1.1 mm, P < 0.0001) and in cases with appendicitis (8.3 ± 2.2 mm vs. 7.0 ± 2.0 mm, P < 0.0001). Mean absolute diameter difference at any location along the appendix was 1.3-1.4 mm in normal appendices and 2 mm in cases of appendicitis. Measured appendiceal diameter differs between US and CT by 1-2 mm, calling into question use of the same diameter cut-off (6 mm) for both modalities for the diagnosis of appendicitis. (orig.)

  14. Results from the 2009 beam commissioning of the CERN multi-turn extraction

    CERN Document Server

    Benedetto, E; Bohl, T; Cettour Cave, S; Cornelis, K; Cotte, D; Damerau, H; Delrieux, M; Fleuret, J; Fowler, T; Follin, F; Franchi, A; Freyermuth, P; Genoud, H; Gilardoni, S; Giovannozzi, M; Hancock, S; Hans, O; Le Borgne, Y; Manglunki, D; Matli, E; Métral, E; Métral, G; Newman, M; Pereira, L; Peters, F; Riva, Y; Roncarolo, F; Sermeus, L; Steerenberg, R; Vandorpe, B; Wenninger, J

    2010-01-01

    Following the analysis of the results obtained during the first year of beam commissioning of the CERN multiturn extraction, a number of changes have been introduced in the beam manipulations performed in the CERN Proton Synchrotron. This includes a different control of the linear chromaticity, the setting of the nonlinear magnets used to split the beam, and the longitudinal structure in the PS. The results obtained during the 2009 run are presented and discussed in detail, including the beam performance in both the PS and the SPS.

  15. Effect of Catalytic Layer Thickness on Diameter of Vertically Aligned Individual Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Hyun Kyung Jung

    2014-01-01

    Full Text Available The effect of catalytic thin film thickness on the diameter control of individual carbon nanotubes grown by plasma enhanced chemical vapor deposition was investigated. Individual carbon nanotubes were grown on catalytic nanodot arrays, which were fabricated by e-beam lithography and e-beam evaporation. During e-beam evaporation of the nanodot pattern, more catalytic metal was deposited at the edge of the nanodots than the desired catalyst thickness. Because of this phenomenon, carbon atoms diffused faster near the center of the dots than at the edge of the dots. The carbon atoms, which were gathered at the interface between the catalytic nanodot and the diffusion barrier, accumulated near the center of the dot and lifted the catalyst off. From the experiments, an individual carbon nanotube with the same diameter as that of the catalytic nanodot was obtained from a 5 nm thick catalytic nanodot; however, an individual carbon nanotube with a smaller diameter (~40% reduction was obtained from a 50 nm thick nanodot. We found that the thicker the catalytic layer, the greater the reduction in diameter of the carbon nanotubes. The diameter-controlled carbon nanotubes could have applications in bio- and nanomaterial scanning and as a contrast medium for magnetic resonance imaging.

  16. Nuclear multifragmentation experiment at the KEK 12 GeV PS. The first results of the KEK-PS E337 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, K.H.; Yamanoi, Y. [National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan); Haseno, M. [and others

    1997-05-01

    A KEK-PS experiment E337 `Angular correlation of intermediate mass fragments emitted from the target multifragmentation reactions with 12 GeV protons` is an extension of the E288 performed a few years ago. The E288 revealed that the proton-induced target multifragmentation reactions at 12 GeV showed quite interesting phenomena such as 70 degree peaking angular distributions for intermediate mass fragments. In December, 1955, the test experiment with 12 GeV protons was started at KEK using this newly constructed counter array of 37 Bragg Curve Counters. The main production experiment was performed in April and May in 1996 after debugging the new counter system and DAQ system, as well as EP1-B beam line. Data with Au, Tm, Sm and Ag targets were successfully accumulated. The data are in the analysis stage, and several interesting features of high energy nuclear reactions have already been seen. (G.K.)

  17. Age and Aortic Diameters in Pilots.

    Science.gov (United States)

    Akın, Ahmet; Ozturk, Cengiz; Aparci, Mustafa; Cakmak, Tolga; Metin, Suleyman; Balta, Sevket; Sen, Ahmet

    2015-12-01

    Pilots are exposed to various physical and hemodynamic stresses during flight. Aortic dilatation may be one of the important consequences of flight-related stress. In this study, we evaluated whether or not variation in aortic diameter was associated with the type of aircraft and the age of pilots. Medical records of 87 jet aircraft pilots (JP) (mean age = 30.0 ± 7.0 years) and 65 non-jet aircraft pilots (NJP) (mean age = 32.63 ± 5.7) were reviewed. Echocardiographic diameters of the aortic sinus (AoS) and ascending aorta (AoAsc) were measured using standard echo probe positions. Aortic diameters were not statistically different between JP and NJP. Regression analysis revealed that the diameters of the AoS (R = 0.484, R(2) = 0.234, p age in the JP group. Whereas, there was not any relationship found between age and the diameters of the AoS and AoAsc in the NJP group. Jet pilots had aortic enlargement as they became older in contrast to the NJP group. Although the aortic diameters were not within the critical ranges in the JP group, these results could suggest that flight-related stresses might result in acute aortic syndromes in the long term. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

  18. Shallow PS-logging by high frequency wave; Koshuha wo mochiita senbu PS kenso

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, A.; Miyazawa, M.; Azuma, H. [OYO Corp., Tokyo (Japan)

    1996-05-01

    This paper describes the following matters on down-hole PS logging in shallow subsurface. Determining an elastic wave velocity structure in shallow subsurface with high accuracy by using down-hole PS logging requires reduction of errors in reading travel time. Therefore, a high-frequency vibration source was fabricated with an objective to raise frequencies of waves used for the measurement. Measurements were made on two holes, A and B, at a measurement interval of 0.5 m, whereas at the hole A a measurement was performed simultaneously by using a normal type (low-frequency) vibration source. A spectral analysis on the waveform record revealed that the frequencies with each vibration source were 127 Hz and 27 Hz for the hole A, 115 Hz for the hole B, and the S/N ratio was all the same for both holes. When the high-frequency vibration source was used, the velocity was determined at accuracy of 5% over the whole length of the shallow section. When the low-frequency vibration source was used, sections with the velocity determining error greater than 5% were found, and it was not possible to derive the velocity structure in the shallow subsurface in fine segments. 3 refs., 8 figs., 2 tabs.

  19. Overview of the Moral Status of iPS Cells.

    Science.gov (United States)

    Martinho, Andreia Martins

    2016-07-01

    The production of induced pluripotent stem (iPS) cells in 2006 by Takahashi and Yamanaka was a major breakthrough in stem cell research. IPS cells technology holds great promise for cell therapy, disease modelling, and drug testing, but it poses ethical questions concerning the moral status of somatic cells, which can re-gain pluripotency (iPS cells). This article provides an overview of the arguments that substantiate the debate on the moral assessment of iPS cells: potentiality argument; relational properties/standard view; and genetic basis for moral status.

  20. PSB LLRF renovation: Initial beam tests of the new digital beam control system

    CERN Document Server

    Angoletta, ME; Butterworth, A; Findlay, A; Pedersen, F; CERN. Geneva. BE Department

    2009-01-01

    The beam control renovation project for CERN’s PS Booster (PSB) was started in autumn 2008. Its aim is to equip all four PSB rings with modern digital beam control systems, characterised by fully-PPM parameters and complete remote control. Additionally, all intermediate and input/output signals are to be remotely acquired in a digital way and in full PPM fashion, and displayed via the Oasis application program. The same digital technology concepts have already been successfully applied to the LEIR beam control system, which has acted as a pilot project for the whole PS Complex renovation project. This new technology allows a very flexible performance and can improve the system maintainability by becoming the standard for the PS Complex beam controls. This note details the first step in the PSB consolidation project, namely the beam control prototype tests carried out on PSB ring 4 in October and November 2008. Both C02 and C04 RF system have been successfully controlled; bunch splitting and extraction synch...

  1. Water data analysis: data reduction from beam and ITC info

    CERN Document Server

    Chelkov, G; Dydak, F; Gostkin, M; Guskov, A; Nefedov, Y; Wotschack, J; Zhemchugov, A

    2004-01-01

    After recalling the motivation for the analysis of water data, the first stage of data reduction is discussed. This data reduction is based on the selection of protons using beam detector data and ITC information. The resolution of the interaction time in the target which serves as reference for time-of-flight measurement of secondaries, is determined with stable beam optics to be 77 ps, otherwise 106 ps. Cuts, their selection efficiency, event numbers, purity of the data sample after cuts, and some ITC characteristics are presented.

  2. Beam Dynamics

    CERN Document Server

    Wilson, E

    2013-01-01

    This document is part of Subvolume C 'Accelerators and Colliders' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the Chapter '2 Beam Dynamics' with the content: 2 Beam Dynamics 2.1 Linear Transverse Beam Dynamics 2.2 Coupling 2.3 Liouville's Theorem 2.4 Momentum Dependent Transverse Motion 2.5 Longitudinal Motion

  3. DiameterJ: A validated open source nanofiber diameter measurement tool.

    Science.gov (United States)

    Hotaling, Nathan A; Bharti, Kapil; Kriel, Haydn; Simon, Carl G

    2015-08-01

    Despite the growing use of nanofiber scaffolds for tissue engineering applications, there is not a validated, readily available, free solution for rapid, automated analysis of nanofiber diameter from scanning electron microscope (SEM) micrographs. Thus, the goal of this study was to create a user friendly ImageJ/FIJI plugin that would analyze SEM micrographs of nanofibers to determine nanofiber diameter on a desktop computer within 60 s. Additional design goals included 1) compatibility with a variety of existing segmentation algorithms, and 2) an open source code to enable further improvement of the plugin. Using existing algorithms for centerline determination, Euclidean distance transforms and a novel pixel transformation technique, a plugin called "DiameterJ" was created for ImageJ/FIJI. The plugin was validated using 1) digital synthetic images of white lines on a black background and 2) SEM images of nominally monodispersed steel wires of known diameters. DiameterJ analyzed SEM micrographs in 20 s, produced diameters not statistically different from known values, was over 10-times closer to known diameter values than other open source software, provided hundreds of times the sampling of manual measurement, and was hundreds of times faster than manual assessment of nanofiber diameter. DiameterJ enables users to rapidly and thoroughly determine the structural features of nanofiber scaffolds and could potentially allow new insights to be formed into fiber diameter distribution and cell response. Published by Elsevier Ltd.

  4. Directed growth of diameter-tunable nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Ozturk, Birol; Talukdar, Ishan; Flanders, Bret N [Department of Physics, Oklahoma State University, 145 Physical Sciences II, Stillwater, OK 74078 (United States)

    2007-09-12

    This study characterizes a method for controlling the nanowire diameter in the directed electrochemical nanowire assembly technique, where alternating voltages applied to electrodes in simple salt solutions induce the crystallization of metallic wires. Dendritic solidification is identified as an important component of this technique. A characteristic of dendritic solidification is that the growth velocity and tip radius are anti-correlated. This relationship is exploited here to realize diameter-tunable nanowire growth. The experimental parameter that provides this control is {omega}, the frequency of the alternating voltage. Increasing {omega} effectively steepens the metal cation concentration gradient at the wire-solution interface, thereby increasing the growth velocity of the wire. For indium wires, increasing {omega} from 0.5 to 3.5 MHz increases their growth velocity from 11 to 78 {mu}m s{sup -1} and reduces their diameter from 770 to 114 nm. Gold wires exhibit diameter-tunability that ranges from 150 nm to 45 nm. Thus, it is possible to tune the wire diameter from the microscale down to the nanoscale. Moreover, this control is a consequence of non-stationary dendritic growth, which distinguishes this process from most previously studied examples of dendritic solidification.

  5. Collagen fibril diameter and leather strength.

    Science.gov (United States)

    Wells, Hannah C; Edmonds, Richard L; Kirby, Nigel; Hawley, Adrian; Mudie, Stephen T; Haverkamp, Richard G

    2013-11-27

    The main structural component of leather and skin is type I collagen in the form of strong fibrils. Strength is an important property of leather, and the way in which collagen contributes to the strength is not fully understood. Synchrotron-based small angle X-ray scattering (SAXS) is used to measure the collagen fibril diameter of leather from a range of animals, including sheep and cattle, that had a range of tear strengths. SAXS data were fit to a cylinder model. The collagen fibril diameter and tear strength were found to be correlated in bovine leather (r(2) = 0.59; P = 0.009), with stronger leather having thicker fibrils. There was no correlation between orientation index, i.e., fibril alignment, and fibril diameter for this data set. Ovine leather showed no correlation between tear strength and fibril diameter, nor was there a correlation across a selection of other animal leathers. The findings presented here suggest that there may be a different structural motif in skin compared with tendon, particularly ovine skin or leather, in which the diameter of the individual fibrils contributes less to strength than fibril alignment does.

  6. Diameter effect on critical heat flux

    Energy Technology Data Exchange (ETDEWEB)

    Tanase, A. [University of Ottawa, Department of Mechanical Engineering, Ottawa, ON (Canada)], E-mail: atana052@uottawa.ca; Cheng, S.C. [University of Ottawa, Department of Mechanical Engineering, Ottawa, ON (Canada); Groeneveld, D.C. [University of Ottawa, Department of Mechanical Engineering, Ottawa, ON (Canada); Chalk River Laboratories, Atomic Energy of Canada Ltd., Chalk River, ON (Canada); Shan, J.Q. [Department of Nuclear Engineering, Xi' an Jiaotong University (China)

    2009-02-15

    The critical heat flux look-up table (CHF LUT) is widely used to predict CHF for various applications, including design and safety analysis of nuclear reactors. Using the CHF LUT for round tubes having inside diameters different from the reference 8 mm involves conversion of CHF to 8 mm. Different authors [Becker, K.M., 1965. An Analytical and Experimental Study of Burnout Conditions in Vertical Round Ducts, Aktiebolaget Atomenergie Report AE 177, Sweden; Boltenko, E.A., et al., 1989. Effect of tube diameter on CHF at various two phase flow regimes, Report IPE-1989; Biasi, L., Clerici, G.C., Garriba, S., Sala, R., Tozzi, A., 1967. Studies on Burnout, Part 3, Energia Nucleare, vol. 14, pp. 530-536; Groeneveld, D.C., Cheng, S.C., Doan, T., 1986. AECL-UO critical heat flux look-up table. Heat Transfer Eng., 7, 46-62; Groeneveld et al., 1996; Hall, D.D., Mudawar, I., 2000. Critical heat flux for water flow in tubes - II subcooled CHF correlations. Int. J. Heat Mass Transfer, 43, 2605-2640; Wong, W.C., 1996. Effect of tube diameter on critical heat flux, MaSC dissertation, Ottawa Carleton Institute for Mechanical and Aeronautical Engineering, University of Ottawa] have proposed several types of correlations or factors to describe the diameter effect on CHF. The present work describes the derivation of new diameter correction factor and compares it with several existing prediction methods.

  7. New safety training for access to the PS complex areas

    CERN Multimedia

    2012-01-01

    Since 10/08/2012, a new course dedicated to the specific radiological risks in the accelerators of the PS complex has been available on SIR (https://sir.cern.ch/). This course complements the general classroom-based Radiation Safety training. Successful completion of the course will be obligatory and verified by the access system as from 01/11/2012 for access to the following accelerator areas: LINAC2, BOOSTER, PS and TT2. Information and reminder e-mails will be sent to all persons currently authorized to access the accelerators of the PS complex. For questions please contact the HSE unit and in particular, the Radiation Protection Group (+41227672504 or safety-rp-ps-complex@cern.ch).

  8. Study of Value Co-Creation in CoPS

    OpenAIRE

    Mingli Zhang; Jianhua Ye

    2013-01-01

    Value co-creation is associated with specific investment in the context of CoPS. The feature of CoPS decides that the study of co-creation cannot execute without regarding asset specificity. This study considers that value co-creation will be associated with specific value, which is outcome of relationship value and asset specificity. Supplier and customer have a close relation, which conducts to specific investment and then it turns to obstacle for competitors. Trust, commitment and satisfac...

  9. Motor-generator set of the PS main supply

    CERN Multimedia

    Photographic Service; CERN PhotoLab

    1968-01-01

    Already in 1964, the PS improvement programme included a new main magnet supply with more power for the longer cycles needed for slow extraction at the full energy of 26 GeV. This motor-generator set was installed in 1967 and took up service at the beginning of 1968. Regularly serviced and fitted with modern electronic regulation, it pulses the PS to this day.

  10. The Libera as a PS orbit measurement system building block

    CERN Document Server

    Belleman, J M; CERN. Geneva. AB Department

    2005-01-01

    During the year 2004, extensive tests using a Libera data processor have been made in order to study its suitability as a building block for a complete PS trajectory and orbit measurement system. The Libera consists of four fast 12-bits ADCs, a Virtex II Pro FPGA and a large memory. This note presents some of the results of the analysis of acquisitions made on a position pick-up in the CERN PS.

  11. DiPS: A Unifying Approach for developing System Software

    OpenAIRE

    Michiels, Sam; Matthijs, Frank; Walravens, Dirk; Verbaeten, Pierre

    2002-01-01

    In this paper we unify three essential features for flexible system software: a component oriented approach, self-adaptation and separation of concerns.We propose DiPS (Distrinet Protocol Stack), a component framework, which offers components, an anonymous interaction model and connectors to handle non-functional aspects such as concurrency. DiPS has effectively been used in industrial protocol stacks and device drivers.

  12. Total domination in graphs with diameter 2

    DEFF Research Database (Denmark)

    Desormeaux, Wyatt J.; Haynes, Teresa W.; Henning, Michael A.

    2014-01-01

    The total domination number γt(G) of a graph G is the minimum cardinality of a set S of vertices, so that every vertex of G is adjacent to a vertex in S. In this article, we determine an optimal upper bound on the total domination number of a graph with diameter 2. We show that for every graph G ...... on n vertices with diameter 2, γt(G)≤1+nln(n). This bound is optimal in the sense that given any ε>0, there exist graphs G with diameter 2 of all sufficiently large even orders n such that γt(G)>(14+ε)nln(n)....

  13. Uniform Fe{sub 3}O{sub 4}-PANi/PS composite spheres with conductive and magnetic properties and their hollow spheres

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xiaocong, E-mail: wangxc@tust.edu.c [Tianjin University of Science and Technology, College of Science (China); Tang Saide [Tianjin University, College of Materials Science and Engineering (China); Liu Jing [Tianjin University of Science and Technology, College of Science (China); He Ziqiong [Tianjin Medical College (China); An Lijuan; Zhang Chenxi; Hao Jingmei [Tianjin University of Science and Technology, College of Science (China); Feng Wei [Tianjin University, College of Materials Science and Engineering (China)

    2009-05-15

    Core-shell multifunctional composite spheres consisting of Fe{sub 3}O{sub 4}-polyaniline (PANi) shell and polystyrene (PS) core were fabricated using core-shell-structured sulfonated PS spheres (with uniform diameter of 250 nm) as templates. PANi was doped in situ by sulfonic acid resulting the composite spheres are well conductive. Dissolved with solvent, PS cores were removed from the core-shell composite spheres and hollow Fe{sub 3}O{sub 4}-PANi spheres were obtained. Removing the PANi and PS components by calcinations produced hollow Fe{sub 3}O{sub 4} spheres. The cavity size of the hollow spheres was uniformly approximate to 190 nm and the shell thickness was 30 nm. The cavity size and the shell thickness can be synchronously controlled by varying the sulfonation time of the PS templates. The shell thickness in size range was of 20-86 nm when the sulfonation time was changed from 1 to 4 h. These resulting spheres could be arranged in order by self-assembly of the templates. Both the Fe{sub 3}O{sub 4}-PANi/PS composite spheres and the hollow Fe{sub 3}O{sub 4} spheres exhibit a super-paramagnetic behavior. Scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray powder scattering were used to characterize these as-prepared spheres.

  14. The PS will soon be back in operation

    CERN Multimedia

    2006-01-01

    The PS's power supply system is undergoing repairs for the accelerator to restart on 26 June. The AB Department's Power Converter Group is working flat out with Siemens to return the PS's power supply system to working order. A problem appeared on the insulation of the power cables of the rotor of the rotating machine (photo) which supplies power to the PS magnets. To prevent more significant damage to the rotating machine, the AB Department, with the approval of the CERN Management, decided to shut down the PS which had started running on 15 May. Everything is being done to restart the accelerator on 26 June. The PS's rotating machine comprises a motor coupled to a generator. The generator's rotor acts like a flywheel, supplying high-power pulses of 40 to 50 megawatts to the PS magnets. The 6 megawatt motor drives the installation at 1000 revolutions per minute and compensates only for variations in speed. It is an essential interface since it would be hard to imagine connecting such an electrical charge, p...

  15. Scaling to Ultra-High Intensities by High-Energy Petawatt Beam Combining

    Energy Technology Data Exchange (ETDEWEB)

    Siders, C W; Jovanovic, I; Crane, J; Rushford, M; Lucianetti, A; Barty, C J

    2006-06-23

    The output pulse energy from a single-aperture high-energy laser amplifier (e.g. fusion lasers such as NIF and LMJ) are critically limited by a number of factors including optical damage, which places an upper bound on the operating fluence; parasitic gain, which limits together with manufacturing costs the maximum aperture size to {approx} 40-cm; and non-linear phase effects which limits the peak intensity. For 20-ns narrow band pulses down to transform-limited sub-picosecond pulses, these limiters combine to yield 10-kJ to 1-kJ maximum pulse energies with up to petawatt peak power. For example, the Advanced Radiographic Capability (ARC) project at NIF is designed to provide kilo-Joule pulses from 0.75-ps to 50-ps, with peak focused intensity above 10{sup 19} W/cm{sup 2}. Using such a high-energy petawatt (HEPW) beamline as a modular unit, they discuss large-scale architectures for coherently combining multiple HEPW pulses from independent apertures, called CAPE (Coherent Addition of Pulses for Energy), to significantly increase the peak achievable focused intensity. Importantly, the maximum intensity achievable with CAPE increases non-linearly. Clearly, the total integrated energy grows linearly with the number of apertures N used. However, as CAPE combines beams in the focal plane by increasing the angular convergence to focus (i.e. the f-number decreases), the foal spot diameter scales inversely with N. Hence the peak intensity scales as N{sup 2}. Using design estimates for the focal spot size and output pulse energy (limited by damage fluence on the final compressor gratings) versus compressed pulse duration in the ARC system, Figure 2 shows the scaled focal spot intensity and total energy for various CAPE configurations from 1,2,4, ..., up to 192 total beams. They see from the fixture that the peak intensity for event modest 8 to 16 beam combinations reaches the 10{sup 21} to 10{sup 22} W/cm{sup 2} regime. With greater number of apertures, or with

  16. iPS-Cinderella Story in Cell Biology

    Directory of Open Access Journals (Sweden)

    Editorial

    2010-01-01

    Full Text Available As we step through the frontiers of modern Science, we are all witnesses to the Cinderella story repeating itself in the form of the iPS. The process of re-programming adult somatic cells to derive Induced Pluripotent stem cells (iPS with the wand of transcription factors and then differentiating them back to adult somatic cells resembles the transformation of Cinderella from a Cinder girl to princess and back to a Cinder girl after the ball; but the iPS-Cinderella is the most fascinating thing ever in cell biology!From the day iPS first made its headlines when it was first produced by Shinya Yamanaka at Kyoto University in Japan, Stem Cell scientists all over the world are re- doing their experiments so far done using other sources like embryonic and adult Stem cells with the iPS cells exploring their potential to the fullest. A Stem Cell science news page without this magic word of iPS is difficult to imagine these days and Scientists have been successful in growing most of the adult Cell types from iPS cells.iPS cells was the key to solve the problems of Immune rejection and Immunosupression required when using other allogeneic Stem cell types which had baffled scientists previously. But the issues raised by scientists about the use of viruses and Oncogenes in producing iPS cells were made groundless when scientists in February 2008 published the discovery of a technique that could remove oncogenes after the induction of pluripotency and now it is possible to induce pluripotency using plasmid transfection, piggyback transposon system and piggyback transposon system combined with a non viral vector system. The word of the day is pIPS which are protein-induced Pluripotent stem cells which are iPS cells that were generated without any genetic alteration of the adult cell. This research by the group of Sheng Ding in La Jolla, California made public in April 2009 showed that the generation of poly-arginine anchors was sufficient to induce

  17. Simulation of a wide area survey for NEOs with Pan-STARRS PS1 & PS2 Telescopes

    Science.gov (United States)

    Chambers, Kenneth C.; Lilly (Schunova), Eva; Dukes, Martin Todd; Wainscoat, Richard J.

    2017-10-01

    We have performed a new survey simulation for a wide area survey with PS1 & PS2 as part of our quest to optimize the discovery rate of Near Earth Objects with the full Pan-STARRS system. The survey is intended to be as unbiased and as complete as possible given the available sky visibility and the anticipated performance of the PS1 and PS2 telescopes working together. The simulation includes a complete model of both telescopes, camera and slew overhead, sky visibility, moon phase, galactic plane exclusion, and weather. The performance of the resulting survey strategy is then evaluated using the method of Lilly et. al. 2017. This uses the Greenstreet et al. 2012 model with 50 million NEOs with absolute magnitudes 13 < H < 29 and the Moving Object Processing System (MOPS, Denneau et al. 2013) for linkages. The results are compared with other possible strategies.

  18. Small diameter nozzle plasma arc as a processing tool

    Science.gov (United States)

    Kimura, T.; Komatsu, A.; Yoshioka, S.; Miyazaki, T.

    1992-06-01

    High-power-density plasma arc equipment with a small diameter nozzle of 0.1-0.3 mm has been developed, which produces power density of about 104 W/mm2 at the exit of the nozzle. The density is comparable to those produced by electron and laser beams. In the present article, development procedure, power density on the target surface, and processing capability in comparison to the conventional electron and laser beams are described. The power density as the processing heat source depends on the kind of processing. The apparent power density in cutting is of the order of 104 W/mm2; on the other hand, that in surface hardening is of the order of 102 W/mm2. The processing capability for causing melting such as cutting and welding does not depend on the working distance, which is defined as the distance between the torch and target material; furthermore, the deviation of the torch from the correct position does not affect the processing capability. The equipment developed is suitable for an automated production system because high precision position control of the torch is not required.

  19. Beam diagnostics

    CERN Document Server

    Raich, U

    2006-01-01

    The instrumentation measuring beam parameters constitutes an important part of any particle accelerator. These lectures aim at giving an overview of detection and measurement techniques without going too much into details of implementation. Instruments for linear accelerators, transfer lines, and small synchrotrons are described with an emphasis on opportunities and problems specific to low-energy particle beams.

  20. Profiling the microRNA Expression in Human iPS and iPS-derived Retinal Pigment Epithelium.

    Science.gov (United States)

    Wang, Heuy-Ching; Greene, Whitney A; Kaini, Ramesh R; Shen-Gunther, Jane; Chen, Hung-I H; Cai, Hong; Wang, Yufeng

    2014-01-01

    The purpose of this study is to characterize the microRNA (miRNA) expression profiles of induced pluripotent stem (iPS) cells and retinal pigment epithelium (RPE) derived from induced pluripotent stem cells (iPS-RPE). MiRNAs have been demonstrated to play critical roles in both maintaining pluripotency and facilitating differentiation. Gene expression networks accountable for maintenance and induction of pluripotency are linked and share components with those networks implicated in oncogenesis. Therefore, we hypothesize that miRNA expression profiling will distinguish iPS cells from their iPS-RPE progeny. To identify and analyze differentially expressed miRNAs, RPE was derived from iPS using a spontaneous differentiation method. MiRNA microarray analysis identified 155 probes that were statistically differentially expressed between iPS and iPS-RPE cells. Up-regulated miRNAs including miR-181c and miR-129-5p may play a role in promoting differentiation, while down-regulated miRNAs such as miR-367, miR-18b, and miR-20b are implicated in cell proliferation. Subsequent miRNA-target and network analysis revealed that these miRNAs are involved in cellular development, cell cycle progression, cell death, and survival. A systematic interrogation of temporal and spatial expression of iPS-RPE miRNAs and their associated target mRNAs will provide new insights into the molecular mechanisms of carcinogenesis, eye differentiation and development.

  1. Beam diagnostics

    CERN Document Server

    Raich, U

    2008-01-01

    Most beam measurements are based on the electro-magnetic interaction of fields induced by the beam with their environment. Beam current transformers as well as beam position monitors are based on this principle. The signals induced in the sensors must be amplified and shaped before they are converted into numerical values. These values are further treated numerically in order to extract meaningful machine parameter measurements. The lecture introduces the architecture of an instrument and shows where in the treatment chain digital signal analysis can be introduced. Then the use of digital signal processing is presented using tune measurements, orbit and trajectory measurements as well as beam loss detection and longitudinal phase space tomography as examples. The hardware as well as the treatment algorithms and their implementation on Digital Signal Processors (DSPs) or in Field Programmable Gate Arrays (FPGAs) are presented.

  2. Diameter preserving linear maps and isometries, II

    Indian Academy of Sciences (India)

    We study linear bijections of simplex spaces A ( S ) which preserve the diameter of the range, that is, the seminorm ϱ ( f ) = sup { | f ( x ) − f ( y ) | : x , y ∈ S } . Author Affiliations. Félix Cabello Sánchez1. Departamento de Matemáticas, Universidad de Extremadura, Avenida de Elvas 06071- Badajoz, Spain. Dates. Manuscript ...

  3. Numerical Analysis of Large Diameter Butterfly Valve

    Science.gov (United States)

    Youngchul, Park; Xueguan, Song

    In this paper, a butterfly valve with the diameter of 1,800 mm was studied. Three-dimensional numerical technique by using commercial code CFX were conducted to observe the flow patterns and to measure flow coefficient, hydrodynamic torque coefficient and so on, when the large butterfly valve operated with various angles and uniform incoming velocity.

  4. Ultrasonic measurement of biparietal diameter and

    African Journals Online (AJOL)

    Summary. Our objective was to verify ultrasonic measurement of biparietal diameter and femur in foetal age determination in the second and third trimester of pregnancy. The prospec- tive cross sectional study was carried out at the ultrasound department of Aberdeen Maternity Hospital Scotland. The study population ...

  5. Beam-time for biology

    CERN Multimedia

    Jordan Juras

    2010-01-01

    There's no question that playing with mercury or handling radioactive cadmium with your bare hands is a risky business. But understanding how these and other toxic metals interact with biomolecules within the body is a challenging feat; one for which the ISOLDE IS488 collaboration hopes to provide valuable insight.   General view of the ISOLDE experimental area. Unlike most of the facilities at CERN's accelerator complex, ISOLDE is not targeted mainly at particle physics. Rather, it produces radioactive nuclei during proton bombardment to study, among other things, physical and biological chemistry. At ISOLDE, the 1.4 GeV proton beam of the PS Booster (an early stage in CERN's accelerator complex) produces nuclear reactions in a thick target, creating a large variety of radioactive nuclei, which are mass-separated for use in experiments. In the case of the IS488 collaboration, the ion beam is directed into ice. "We implant radioactive metal ions into ice", explains Monika Stac...

  6. Shaping micron-sized cold neutron beams

    Energy Technology Data Exchange (ETDEWEB)

    Ott, Frédéric, E-mail: Frederic.Ott@cea.fr [CEA, IRAMIS, Laboratoire Léon Brillouin, Gif-sur-Yvette F-91191 (France); CNRS, IRAMIS, Laboratoire Léon Brillouin, Gif-sur-Yvette F-91191 (France); Kozhevnikov, Sergey [Joint Institute for Nuclear Research, ul. Joliot-Curie 6, Dubna, Moscow oblast 141980 (Russian Federation); Thiaville, André [Laboratoire de Physique des Solides, Univ. Paris—Sud, CNRS UMR 8502, 91405 Orsay (France); Torrejón, Jacob [Unité Mixte de Physique, CNRS/Thales, Campus de l’Ecole Polytechnique, 91767 Palaiseau (France); Vázquez, Manuel [Instituto de Ciencia de Materiales, CSIC, 28049 Madrid (Spain)

    2015-07-11

    In the field of neutron scattering, the need for micro-sized (1–50 µm) thermal or cold neutron beams has recently appeared, typically in the field of neutron imaging to probe samples with a high spatial resolution. We discuss various possibilities of producing such micro-sized neutron beams. The advantages and drawbacks of the different techniques are discussed. We show that reflective optics offers the most flexible way of producing tiny neutron beams together with an enhanced signal to background ratio. The use of such micro beams is illustrated by the study of micrometric diameter magnetic wires.

  7. Fractional laser photothermolysis using Bessel beams.

    Science.gov (United States)

    Mignon, Charles; Rodriguez, Aura Higuera; Palero, Jonathan A; Varghese, Babu; Jurna, Martin

    2016-12-01

    Fractional photothermolysis uses lasers to generate a pattern of microscopic columnar thermal lesions within the skin stimulating collagen remodeling. In this paper we investigate the use of Bessel beams as an alternative to conventional Gaussian beams in creating laser photothermal lesions of different aspect ratios in skin. We show for the first time the improved photothermal lesion depth-to-diameter aspect ratio using Bessel beams in ex vivo human skin as well as in numerical simulations using electric field Monte Carlo photon transport, finite difference methods and Arrhenius model. Bessel beams allow the creation of deep and narrow thermal lesions necessary for improved efficacy in fractional photothermolysis.

  8. Overview of the CERN Linac4 beam instrumentation

    CERN Document Server

    Roncarolo, F; Bravin, E; Dehning, B; Duraffourg, M; Gerard, D; Holzer, E B; Lenardon, F; Focker, G; Raich, U; Soby, L; Sordet, M; Tan, J; Tranquille, G; Vuitton, C; Zamantzas, C; Cheymol, B

    2010-01-01

    The CERN LINAC4 will represent the first upgrade of the LHC injection chain, by accelerating H- ions from 45 KeV to 160 MeV for charge-exchange injection into the PS Booster. In order to provide its safe and efficient commissioning and operation, a wide variety of beam diagnostics devices has been designed for installation at convenient locations all over the accelerator length and in the transfer line to the PS Booster. This paper gives an overview of all instrumentation devices, including those to measure beam position, transverse and longitudinal profile, beam current and beam loss. The well advanced status of the system design and the main instrument features are discussed

  9. High Intensity Beam Issues in the CERN Proton Synchrotron

    CERN Document Server

    Aumon, Sandra; Rivkin, Leonid

    This PhD work is about limitations of high intensity proton beams observed in the CERN Proton Synchrotron (PS) and, in particular, about issues at injection and transition energies. With its 53 years, the CERN PS would have to operate beyond the limit of its performance to match the future requirements. Beam instabilities driven by transverse impedance and aperture restrictions are important issues for the operation and for the High-Luminosity LHC upgrade which foresees an intensity increase delivered by the injectors. The main subject of the thesis concerns the study of a fast transverse instability occurring at transition energy. The proton beams crossing this energy range are particularly sensitive to wake forces because of the slow synchrotron motion. This instability can cause a strong vertical emittance blow-up and severe losses in less than a synchrotron period. Experimental observations show that the particles at the peak density of the beam longitudinal distribution oscillate in the vertical plane du...

  10. Test Beam Measurements on Picosec Gaseous Detector.

    CERN Document Server

    Sohl, Lukas

    2017-01-01

    In the Picosec project micro pattern gaseous detectors with a time resolution of some ten picoseconds are developed. The detectors are based on Micromegas detectors. With a cherenkov window and a photocathode the time jitter from different position of the primary ionization clusters can be substituted. This reports describes the beam setup and measurements of different Picosec prototypes. A time resolution of under 30 ps has been measured during the test beam. This report gives an overview of my work as a Summer Student. I set up and operated a triple-GEM tracker and a trigger system for the beam. During the beam I measured different prototypes of Picosec detectors and analysed the data.

  11. Spot-to-Beam Procedure

    CERN Document Server

    Seidov, Zakir F; Yahalom, Asher

    2004-01-01

    We describe the interactive "STB" (spot_to_beam) MATHEMATICA procedure for a) approximating the spot image at the screen as ellipse, b) getting five parameters of the elliptic beam (two diameters, center coordinates, and orientation angle). The basic idea is to "map" the reference holes at screen onto the X-Y plane normal to the beam direction (Z-axis). All distortions of the image, e.g., due to camera-screen disposition can be, in principle, taken into account,assuming that the hole positions at screen and the orientation of the screen are known. With the non-linear LMS fitting, the "curved-coordinate-system" of the holes at image is transferred to the Cartesian coordinate system at XY-plane. Then the fitting ellipse is found in this latter system, by solving the system of N linear equations for 5 unknown parameters of beam ellipse, where N>5 is a number of reference points on edge of spot image. The examples of the real measurements at various screens will be demonstrated. The accuracy of beam diameters is ...

  12. Construction of a pulsed MeV positron beam line

    Energy Technology Data Exchange (ETDEWEB)

    Masuno, Shin-ichi; Okada, Sohei; Kawasuso, Atsuo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    To develop a fast (1 MeV) and short pulsed (100 ps) positron beam which enables defect behavior analysis of bulk states of materials even at high temperatures where a usual positron source would melt, we have been performing design study and construction of the beam line in a three-year program since 1994. This report describes the components, design study results and experimental results of the completed parts until now. (author)

  13. Pressure Monitoring Using Hybrid fs/ps Rotational CARS

    Science.gov (United States)

    Kearney, Sean P.; Danehy, Paul M.

    2015-01-01

    We investigate the feasibility of gas-phase pressure measurements at kHz-rates using fs/ps rotational CARS. Femtosecond pump and Stokes pulses impulsively prepare a rotational Raman coherence, which is then probed by a high-energy 6-ps pulse introduced at a time delay from the Raman preparation. Rotational CARS spectra were recorded in N2 contained in a room-temperature gas cell for pressures from 0.1 to 3 atm and probe delays ranging from 10-330 ps. Using published self-broadened collisional linewidth data for N2, both the spectrally integrated coherence decay rate and the spectrally resolved decay were investigated as means for detecting pressure. Shot-averaged and single-laser-shot spectra were interrogated for pressure and the accuracy and precision as a function of probe delay and cell pressure are discussed. Single-shot measurement accuracies were within 0.1 to 6.5% when compared to a transducer values, while the precision was generally between 1% and 6% of measured pressure for probe delays of 200 ps or more, and better than 2% as the delay approached 300 ps. A byproduct of the pressure measurement is an independent but simultaneous measurement of the gas temperature.

  14. Synthesis of ZnO thin films by 40 ps rate at 532 nm laser pulses

    Energy Technology Data Exchange (ETDEWEB)

    Ristoscu, C.; Socol, G.; Mihailescu, I.N. [National Institute for Lasers, Plasma and Radiations Physics, Lasers Department, 409 Atomistilor, P.O. Box MG-54, Magurele, Ilfov (Romania); Socol, M. [National Institute for Materials Physics, P.O. Box MG-7, Magurele, Ilfov (Romania); Jafer, R.; Al-Hadeethi, Y.; Batani, D. [Universita degli Studi di Milano-Bicocca, Dipartimento di Fisica ' ' G. Occhialini' ' , Milano (Italy)

    2011-09-15

    The synthesis by pulsed laser deposition of ZnO thin films with a Nd:YAG laser system delivering pulses of 40 ps rate at 532 nm is reported. The laser beam irradiated the target placed inside a vacuum chamber evacuated down to 1.33 x 10{sup -1} Pa. The incident laser fluence was of 28 J/cm{sup 2} in a spot of 0.1 mm{sup 2}. The ablated material was collected onto double face polished (111) Si or quartz wafers placed parallel at a separation distance of 7 mm. The AFM, SEM, UV-Vis, FT-IR and absorption ellipsometry results indicated that we obtained pure ZnO films with a rather uniform surface, having an average roughness of 37 nm. We observed by SEM that particulates are present on ZnO film surface or embedded into bulk. Their density and dimension were intermediary between particulates observed on similar structures deposited with fs or ns laser pulses. We noticed that the density of the particulates is increasing while their average size is decreasing when passing from ns to ps and fs laser pulses. The average transmission in the UV-Vis spectral region was found to be higher than 85%. (orig.)

  15. New Control Structure of the 10 MHz RF System in the CERN PS

    CERN Document Server

    Damerau, H

    2013-01-01

    The 10MHz cavities comprise the main RF system in the CERN PS and the only one that allows acceleration. In total 11 tunable cavities (10 operational and a hot spare, grouped into 3+1 tuning groups and up to presently 6 voltage program groups) are distributed all around the circumference of the PS ring. Next to the RF drive signal each of the cavities is controlled by a voltage program and timing pulses to open and close the relays to short-circuit the cavity gaps. These control signals are presently generated by a dedicated hardware matrix. It translates voltage functions and relay timing pulses per cavity group into functions and timings per cavity. However, due to its central position in the RF beam control system, the dedicated hardware matrix can cause significant downtime in case of a major hardware failure. Instead of upgrading the existing obsolete hardware, this note suggests a replacement by standard controls hardware and dedicated application software. Thanks to advanced software concepts like “M...

  16. On finding minimum-diameter clique trees

    Energy Technology Data Exchange (ETDEWEB)

    Blair, J.R.S. (Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science); Peyton, B.W. (Oak Ridge National Lab., TN (United States))

    1991-08-01

    It is well-known that any chordal graph can be represented as a clique tree (acyclic hypergraph, join tree). Since some chordal graphs have many distinct clique tree representations, it is interesting to consider which one is most desirable under various circumstances. A clique tree of minimum diameter (or height) is sometimes a natural candidate when choosing clique trees to be processed in a parallel computing environment. This paper introduces a linear time algorithm for computing a minimum-diameter clique tree. The new algorithm is an analogue of the natural greedy algorithm for rooting an ordinary tree in order to minimize its height. It has potential application in the development of parallel algorithms for both knowledge-based systems and the solution of sparse linear systems of equations. 31 refs., 7 figs.

  17. Prospect for Charge Current Neutrino Interactions Measurements at the CERN-PS

    CERN Document Server

    Stanco, Luca (INFN-Padova)

    2011-01-01

    Tensions in several phenomenological models grew with experimental results on neu- trino/antineutrino oscillations at Short-Baseline (SBL) and with the recent, carefully recomputed, antineutrino fluxes from nuclear reactors. At a refurbished SBL CERN- PS facility an experiment aimed to address the open issues has been proposed [1], based on the technology of imaging in ultra-pure cryogenic Liquid Argon (LAr). Motivated by this scenario a detailed study of the physics case was performed. We tackled specific physics models and we optimized the neutrino beam through a full simulation. Experimental aspects not fully covered by the LAr detection, i.e. the measurements of the lepton charge on event-by-event basis and their energy over a wide range, were also investigated. Indeed the muon leptons from Charged Current (CC) (anti-)neutrino interactions play an important role in disentangling different phenomenological scenarios provided their charge state is determined. Also, the study of muon appearance/disappearance...

  18. Prospect for Charge Current Neutrino Interactions Measurements at the CERN-PS

    CERN Document Server

    Bernardini, P; Bozza, C; Brugnera, R; Cecchetti, A; Cecchini, S; Collazuol, G; Corso, F Dal; De Mitri, I; De Serio, M; Di Ferdinando, D; Dore, U; Dusini, S; Fabbricatore, P; Fanin, C; Fini, R A; Garfagnini, A; Grella, G; Kose, U; Laveder, M; Loverre, P; Longhin, A; Marsella, G; Mancarella, G; Mandrioli, G; Mauri, N; Medinaceli, E; Mezzetto, M; Muciaccia, M T; Orecchini, D; Paoloni, A; Pastore, A; Patrizii, L; Pozzato, M; Rescigno, R; Rosa, G; Simone, S; Sioli, M; Sirri, G; Spurio, M; Stanco, L; Stellacci, S; Surdo, A; Tenti, M; Togo, V

    2011-01-01

    Tensions in several phenomenological models grew with experimental results on neutrino/antineutrino oscillations at Short-Baseline (SBL) and with the recent, carefully recomputed, antineutrino fluxes from nuclear reactors. At a refurbished SBL CERN-PS facility an experiment aimed to address the open issues has been proposed [1], based on the technology of imaging in ultra-pure cryogenic Liquid Argon (LAr). Motivated by this scenario a detailed study of the physics case was performed. We tackled specific physics models and we optimized the neutrino beam through a full simulation. Experimental aspects not fully covered by the LAr detection, i.e. the measurements of the lepton charge on event-by-event basis and their energy over a wide range, were also investigated. Indeed the muon leptons from Charged Current (CC) (anti-)neutrino interactions play an important role in disentangling different phenomenological scenarios provided their charge state is determined. Also, the study of muon appearance/disappearance ca...

  19. Model based, detailed fault analysis in the CERN PS complex equipment

    CERN Document Server

    Beharrell, M; Bouché, J M; Cupérus, J; Lelaizant, M; Mérard, L

    1995-01-01

    In the CERN PS Complex of accelerators, about a thousand of equipment of various type (power converters, RF cavities, beam measurement devices, vacuum systems etc...) are controlled using the so-called Control Protocol, already described in previous Conferences. This Protocol, a model based equipment access standard, provides, amongst other facilities, a uniform and structured fault description and report feature. The faults are organized in categories, following their gravity, and are presented at two levels: the first level is global and identical for all devices, the second level is very detailed and adapted to the peculiarities of each single device. All the relevant information is provided by the equipment specialists and is appropriately stored in static and real time data bases; in this way a unique set of data driven application programs can always cope with existing and newly added equipment. Two classes of applications have been implemented, the first one is intended for control room alarm purposes,...

  20. Beam intensity measurement system for proton synchrotron booster

    Science.gov (United States)

    Belohrad, David; Kasprowicz, Grzegorz

    2006-10-01

    The PS Booster delivers particles for most of the CERN experiments. The PS complex will become particle source for LHC in 2007. For this reason PS complex electronics is continuously upgraded to meet new requirements in performance and remote management. A new acquisition system has been developed to allow the measurement of the individual intensity of each bunch in a 1Hz bunch train. Such a system will be used for the measurement of beams at the injection, ejection and acceleration lines . The method is based on integrating of the analogue signal supplied by a Beam Current Transformer. The signal is sampled by two 12 bits ADCs with 20x oversampling. The output of ADC is then processed in FPGA, where the rest of the signal processing is performed. The measurement system was build as a standard VME module. Apart from that, on same board there were implemented current and charge calibrators.

  1. Beam collimator

    CERN Multimedia

    1977-01-01

    A four-block collimator installed on a control table for positioning the alignment reference marks. Designed for use with SPS secondary beams, the collimator operates under vacuum conditions. See Annual Report 1976 p. 121 and photo 7701014.

  2. Final Results on the CERN PS Electrostatic Septa Consolidation Program

    CERN Document Server

    Borburgh, Jan; Bobbio, Piero; Carlier, Etienne; Hourican, Michael; Masson, Thierry; Müller, Tania; Prost, Antoine; Crescenti, Massimo

    2003-01-01

    The CERN PS electrostatic septum consolidation program is coming to completion after almost 4 years of development. The program was started to fulfil the increased requirements on vacuum performance and the need to reduce the time necessary for maintenance interventions. The new design of septum 31, used for the so-called 'continuous transfer' 5-turn extraction, and the related construction issues will be presented together with the operational experience gained during the PS 2002 run. In addition, the experience of two years of operation with the new generation septum 23, used for a resonant slow extraction, will be briefly discussed. The continued development undertaken since its installation in the PS ring in 2001 will also be described.

  3. SAFETY: STRICTER CONTROLS IN CONTROLLED AREAS IN THE PS

    CERN Document Server

    G. Daems

    2001-01-01

    The PS accelerators will soon stop for several months. Work will take place in controlled areas in the PS and will involve many people who are not always aware of the risks associated with the work sites. To guarentee the safety of these workers, the following two measures will be applied: everyone working in a controlled zone - Linacs, PSB, and PS machines tunnels, and transfer lines - must wear, visibly, his CERN access card and his film badge. the CERN access card and the film badge will only be issued after following a basic safety course. Regular checks will be carried out during the shutdown. Anyone without these two items on their person will be obliged to leave the area immediately.

  4. Electrophysical properties of PMN-PT-PS-PFN:Li ceramics

    Directory of Open Access Journals (Sweden)

    R. Skulski

    2013-01-01

    Full Text Available We present the technology of obtaining and the electrophysical properties of a multicomponent material 0.61PMN-0.20PT-0.09PS-0.1PFN:Li (PMN-PT-PS-PFN:Li. The addition of PFN into PMN-PT decreases the temperature of final sintering which is very important during technological process (addition of Li decreases electric conductivity of PFN. Addition of PS i.e., PbSnO3 (which is unstable in ceramic form permits to shift the temperature of the maximum of dielectric permittivity. One-step method of obtaining ceramic samples from oxides and carbonates has been used. XRD, microstructure, scanning calorimetry measurements and the main dielectric, ferroelectric and electromechanical properties have been investigated for the obtained samples.

  5. Effect of interfaces on the melting of PEO confined in triblock PS-b-PEO-b-PS copolymers.

    Science.gov (United States)

    Beaudoin, E; Phan, T N T; Robinet, M; Denoyel, R; Davidson, P; Bertin, D; Bouchet, R

    2013-08-27

    Block copolymers form nanostructures that have interesting physical properties because they combine, for a single compound, the complementary features brought by each block. However, in order to fully exploit these properties, the physical state of each kind of domain must be precisely controlled. In this work, triblock PS-b-PEO-b-PS copolymers consisting of a central poly(ethylene oxide) (PEO) block covalently bonded to polystyrene (PS) blocks were synthesized by Atom Transfer Radical Polymerization. Their morphology was investigated by X-ray scattering and TEM experiments whereas their thermodynamic behavior was characterized by DSC. A strong decrease of both the melting temperature and the degree of crystallinity of PEO, due to its confinement between the PS domains, was observed and analyzed with a modified Gibbs-Thomson equation, following the approaches used for fluids confined in porous media. The existence of an amorphous bound layer, a few nanometers thick, at the PEO/PS interface, that does not undergo any phase transition in the temperature range investigated, accounts for both the melting temperature depression and the decrease of crystallinity upon confinement. This interfacial layer may significantly affect the mechanical and transport properties of these block copolymers that find applications as solid polymer electrolytes in batteries for example. Moreover, the value obtained for the solid PEO/liquid PEO surface tension is lower than those previously published but is thermodynamically consistent with the surface tensions of polymers at the solid/vapor and liquid/vapor interfaces.

  6. Inauguration of POPS: the new power system of the PS

    CERN Multimedia

    Maximilien Brice

    2010-01-01

    Pictures 03 and 04 : The team from the Electrical Power Converters Group (TE/EPC) is joined by the Director of Accelerators, the heads of the BE, TE and FI departments, CERN managers and Converteam representatives in a group portrait in front of three of the containers that house the capacitor banks of the PS's new power supply system, POPS. Pictures 01, 06 and 07 : Magid-Michel Saikaly, energy and infrastructure director at Converteam, receives a prize from Steve Myers, Director of Accelerators at CERN, for the development and fabrication of the new electrical power system for the PS, called POPS.

  7. The Septa for LEIR Extraction and PS Injection

    CERN Document Server

    Borburgh, J; Masson, T; Prost, A

    2006-01-01

    The Low Energy Ion Ring (LEIR) is part of the CERN LHC injector chain for ions. The LEIR extraction uses a pulsed magnetic septum, clamped around a metallic vacuum chamber. Apart from separating the ultra high vacuum in the LEIR ring from the less good vacuum in the transfer line to the PS this chamber also serves as magnetic screen and retains the septum conductor in place. The PS ion injection septum consists of a pulsed laminated magnet under vacuum, featuring a single-turn water cooled coil and a remote positioning system. The design, the construction and the commissioning of both septa are described.

  8. To Test a Prototype of a Proton Lifetime Detector in a Neutrino Beam at the PS

    CERN Multimedia

    2002-01-01

    In order to test the performances of the calorimeter method in a nucleon lifetime experiment, a 3 ton prototype calorimeter made of iron and polystyrene scintillator sandwiches and of fine-grain counters has been designed by our collaboration. The energy and angular resolution will be tested by exposing this prototype to charged particles ($e, \\mu , \\pi$) in the 0.5 GeV/c range at Orsay and at CERN in Summer 1980. Since an unavoidable background to any experiment on nucleon decay consists of atmospheric neutrino events, which could in some cases simulate a nucleon decay, the knowledge of the configuration of such events in our detector is essential. It has been shown that the energy distribution of the $\

  9. Beam Tests and Plans for the CERN PS Transverse Damper System

    CERN Document Server

    Blas, A; Sterbini, G

    2013-01-01

    The CERN Proton Synchrotron (CPS) has been running without any transverse damping equipment since 1998, thanks to the stabilizing effect of the linear coupling applied between horizontal and vertical planes. \

  10. The OMERACT psoriatic arthritis magnetic resonance imaging scoring system (PsAMRIS): definitions of key pathologies, suggested MRI sequences, and preliminary scoring system for PsA Hands

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; McQueen, Fiona; Wiell, Charlotte

    2009-01-01

    This article describes a preliminary OMERACT psoriatic arthritis magnetic resonance image scoring system (PsAMRIS) for evaluation of inflammatory and destructive changes in PsA hands, which was developed by the international OMERACT MRI in inflammatory arthritis group. MRI definitions of important...... pathologies in peripheral PsA and suggestions concerning appropriate MRI sequences for use in PsA hands are also provided....

  11. Cyclotron for Beam Therapy Application

    CERN Document Server

    Alenitsky, Yu G; Karamysheva, G A; Kostromin, S A; Mitsyn, G V; Molokanov, A G; Onishchenko, L M; Samsonov, E V; Vorozhtsov, S B; Zaplatin, N L

    2005-01-01

    The basic parameters of the proton isochronous cyclotron on the fixed energy are considered. The energy of protons is $E_{p}\\sim $ 220~MeV, intensity of the extracted beam is $I_{p}\\sim $ 0.1~$\\mu$A. The cyclotron is projected on the basis of compact magnet with four sectors and the diameter of poles 300 cm. Two dees of the accelerating system are located in valleys.

  12. Injection septa position and angle optimisation in view of the 2 GeV liu upgrade of the CERN PS

    CERN Document Server

    Serluca, HM; Forte, V; Fraser, M; Sterbini, G

    2017-01-01

    In the framework of the LHC Injector Upgrade (LIU)project the CERN PS injection kinetic energy will be up-graded from 1.4 to 2 GeV. The injection equipment, whichis already operating close to its limit, is being redesigned tocope with 30% increase in the beam rigidity. In this paper wepresent the experimental results from Machine Development(MD) studies on the present septum to explore its operationalhardware limits with respect to aperture restrictions, beamlosses and kick strengths in view of the LIU upgrade

  13. Low Noise Signal Processing Technique for Monopulse Pointing of DSN 34-meter Diameter Antennas

    Science.gov (United States)

    Gudim, M.; Gawronski, W.

    2000-01-01

    This paper describes a 31.8 - 32.3 GHz (Ka-band) monopulse antenna pointing system designed to meet a pointing precision requirement of a mean-radial-error (MRE) less than 1.5 milli-degrees for a 34-meter diameter antenna with a 17 milli-degree 3-dB beam-width, under windy conditions up to 15mph.

  14. Variable diameter wind turbine rotor blades

    Science.gov (United States)

    Jamieson, Peter McKeich; Hornzee-Jones, Chris; Moroz, Emilian M.; Blakemore, Ralph W.

    2005-12-06

    A system and method for changing wind turbine rotor diameters to meet changing wind speeds and control system loads is disclosed. The rotor blades on the wind turbine are able to adjust length by extensions nested within or containing the base blade. The blades can have more than one extension in a variety of configurations. A cable winching system, a hydraulic system, a pneumatic system, inflatable or elastic extensions, and a spring-loaded jack knife deployment are some of the methods of adjustment. The extension is also protected from lightning by a grounding system.

  15. Optimization of protease production by an actinomycete Strain, PS ...

    African Journals Online (AJOL)

    Actinomycetes were isolated from the sediment samples of an estuarine shrimp pond located along the south east coast of India. During the investigation, a total of 28 strains of actinomycetes were isolated and examined for their protease activity. Among them, one strain PS-18A which was tentatively identified as ...

  16. Seismic receiver function interpretation: Ps splitting or anisotropic underplating?

    Science.gov (United States)

    Liu, Zhen; Park, Jeffrey

    2017-03-01

    Crustal anisotropy is crucial to understanding the evolutionary history of Earth's lithosphere. Shear wave splitting of Moho P-to-S converted phases in receiver functions (RFs) have been often used to study crustal anisotropy. Harmonic variation of Moho Ps phases in delay times are used to infer splitting parameters of averaged anisotropy in the crust. However, crustal anisotropy may distribute at various levels within the crust due to complex deformational processes. Layered anisotropy requires careful investigation of the distribution of anisotropy before interpreting Moho Ps splitting. In this study, we show results from stations ARU in Russia, KIP in the Hawaiian Islands and LSA in Tibetan Plateau, where layered anisotropy is constrained well by intracrust Ps conversions at high frequencies using a harmonic-decomposition technique. Anisotropic velocity models are inferred by forward-modeling decomposed RF waveforms. We suggest that the harmonic variation of Moho Ps phases should always be investigated to check for anisotropic layering using RFs with frequency content above 1 Hz, rather than simply reporting averaged anisotropy of the whole crust.

  17. Optimization of protease production by an actinomycete Strain, PS ...

    African Journals Online (AJOL)

    STORAGESEVER

    Isolation Agar Medium in duplicate Petri plates. To minimize ... on the Petri plates were counted from 5th day onwards, up to 28th .... After the dialysis, the volume was measured and analyzed for proteins and stored in deep freezer. Taxonomic investigation. The genus level identification was made for the strain PS-18A using ...

  18. Framing Retention for Institutional Improvement: A 4 Ps Framework

    Science.gov (United States)

    Kalsbeek, David H.

    2013-01-01

    A 4 Ps framework for student retention strategy is a construct for reframing the retention discussion in a way that enables institutional improvement by challenging some conventional wisdom and prevailing perspectives that have characterized retention strategy for years. It opens new possibilities for action and improvement by suggesting that…

  19. The Swelling Behaviour of Polystyrene (PS)/ Polyvinylacetate (Pvac ...

    African Journals Online (AJOL)

    The effect of the variation of the type of solvent responsible for the differences in the swelling kinetics of Polystyrene (PS) and Polyvinyl acetate (PVAc) blends was studied. The results showed that the nature of solvent control or affects the degree of swelling. Also, 1-V characteristics at temperature range of 323-363K shows ...

  20. Boiling treatment of ABS and PS plastics for flotation separation.

    Science.gov (United States)

    Wang, Chong-qing; Wang, Hui; Wu, Bao-xin; Liu, Qun

    2014-07-01

    A new physical method, namely boiling treatment, was developed to aid flotation separation of acrylonitrile-butadiene-styrene (ABS) and polystyrene (PS) plastics. Boiling treatment was shown to be effective in producing a hydrophilic surface on ABS plastic. Fourier Transform Infrared analysis was conducted to investigate the mechanism of boiling treatment of ABS. Surface rearrangement of polymer may be responsible for surface change of boiling treated ABS, and the selective influence of boiling treatment on the floatability of boiling treated plastics may be attributed to the difference in the molecular mobility of polymer chains. The effects of flotation time, frother concentration and particle size on flotation behavior of simple plastic were investigated. Based on flotation behavior of simple plastic, flotation separation of boiling treatment ABS and PS with different particle sizes was achieved efficiently. The purity of ABS and PS was up to 99.78% and 95.80%, respectively; the recovery of ABS and PS was up to 95.81% and 99.82%, respectively. Boiling treatment promotes the industrial application of plastics flotation and facilitates plastic recycling. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Factors affecting common bile duct diameter.

    Science.gov (United States)

    Daradkeh, Salam; Tarawneh, Emad; Al-Hadidy, Azmy

    2005-01-01

    The purpose of the study was to see the effect of age, sex, body mass index, previous cholecystectomy, hepatomegaly and fasting status on the common bile duct diameter. A series of 463 patients, 283 females and 180 males, with no hepatobiliary or pancreatic pathology were included in this study, the mean age was 45 +/- 16 years. Their age, sex, weight, height, fasting status and previous cholecystectomy was assessed and recorded by a physician prior to ultrasound examination. All patients were examined by real-time ultrasound to see if there was any pathology in the hepatobiliary and pancreatic area. Those with history of common bile duct exploration, endoscopic sphincterotomy or with previous history of cholecystectomy of less than 6 months and patients with common bile duct pathology were excluded from the study. The midportion of the common bile duct was taken as a fixed measurement for all patients and the size of the liver was also recorded. Analysis of variance as part of SPSS statistical package was used where common bile duct was considered a dependent variable, while sex, fasting status, hepatomegaly and previous cholecystectomy were considered to be independent variables, age and sex were considered as co-variants. The factors found to be significantly affecting the diameter of the common bile duct (P<0.05) were age, previous cholecystectomy and body mass index. If the CBD dilatation can not be explained by age, previous cholecystectomy and BMI, a pathology causing obstruction should be ruled out.

  2. Sagittal Abdominal Diameter: Application in Clinical Practice

    Directory of Open Access Journals (Sweden)

    Thaís Da Silva-Ferreira

    2014-05-01

    Full Text Available Excess visceral fat is associated with cardiovascular risk factors. Sagittal abdominal diameter (SAD has recently been highlighted as an indicator of abdominal obesity, and also may be useful in predicting cardiovascular risk. The purpose of the present study was to review the scientific literature on the use of SAD in adult nutritional assessment. A search was conducted for scientific articles in the following electronic databases: SciELO , MEDLINE (PubMed and Virtual Health Library. SAD is more associated with abdominal fat (especially visceral, and with different cardiovascular risk factors, such as, insulin resistance, blood pressure, and serum lipoproteins than the traditional methods of estimating adiposity, such as body mass index and waist-to-hip ratio. SAD can also be used in association with other anthropometric measures. There are still no cut-off limits established to classify SAD as yet. SAD can be an alternative measure to estimate visceral adiposity. However, the few studies on this diameter, and the lack of consensus on the anatomical site to measure SAD, are obstacles to establish cut-off limits to classify it.

  3. Recent results on the solar diameter

    Science.gov (United States)

    Wittmann, A. D.; Alge, E.; Bianda, M.

    1991-10-01

    Using optically identical telescopes at different sites, the solar diameter is measured with a drift-scan technique. In order to investigate the cause of the observed fluctuations, observations made simultaneously by different observers at the same telescope are compared as are observations made simultaneously at two different sites. It is found that the mean error of a single drift time measurement is +/-0.08 s (or +/- 1.1 arcsec) at Izana and +/-0.11 s (or +/- 1.7 arcsec) at Locarno; this closely corresponds to the angular resolution at those two sites under normal seeing conditions. No correlation is found between observations at different sites; a significant correlation exists, however, between observations made simultaneously by different observers at the same site. This indicates that most of the observed fluctuations are due to atmospheric effects rather than personality effects. The mean solar semidiameter derived from a total of 1122 observations made in 1990 is R = (960.56 +/-0.03) arcsec; this may be compared with R = (960.32 +/-0.02) arcsec which is obtained from a reanalysis of 1773 observations made in 1981. Although a small residual increase of the solar diameter during the last 10 years seems to be indicated, most - if not all - of the observed varitions are due to variable seeing conditions, and there is still no conclusive evidence for a genuine solar variation with amplitudes in excess of about +/-0.3 arcsec.

  4. Several view of the TRD Beam machine.

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    Photo 1: Oliver Busch, a member of ALICE TRD team, in fron of the TRD prototypes at the T10 beamline. Photo 3: A close-up view of the four identical layers of ALICE TRD prototypes under tests in pion/electron beams at CERN PS. Photo 5: Four layers of Transition Radiation Detector (left side) together with auxiliary detectors (silicon microstrip, scintillators and Cherenkov) at PS T10 beam line. Photo 6: Full view of the setup used to test Transition Radiation Detector (TRD) prototypes for ALICE experiment. Four identical layers of TRD are on the left of the picture, preceded by scintillation detectors used to define the beam and by Cherenkov detectors (the two long cylinders) used to identify electrons. Photo 8: Full view of ALICE TRD prototype test setup with two Cherenkov detectors in the foreground. The Cherenkov detectors are essential to identify the electrons in the mixed pion/electron beam at the CERN Proton Synchrotron. Photo 9: Full view of TRD prototype tests setup. Two Cherenkov detectors are...

  5. psRNATarget: a plant small RNA target analysis server.

    Science.gov (United States)

    Dai, Xinbin; Zhao, Patrick Xuechun

    2011-07-01

    Plant endogenous non-coding short small RNAs (20-24 nt), including microRNAs (miRNAs) and a subset of small interfering RNAs (ta-siRNAs), play important role in gene expression regulatory networks (GRNs). For example, many transcription factors and development-related genes have been reported as targets of these regulatory small RNAs. Although a number of miRNA target prediction algorithms and programs have been developed, most of them were designed for animal miRNAs which are significantly different from plant miRNAs in the target recognition process. These differences demand the development of separate plant miRNA (and ta-siRNA) target analysis tool(s). We present psRNATarget, a plant small RNA target analysis server, which features two important analysis functions: (i) reverse complementary matching between small RNA and target transcript using a proven scoring schema, and (ii) target-site accessibility evaluation by calculating unpaired energy (UPE) required to 'open' secondary structure around small RNA's target site on mRNA. The psRNATarget incorporates recent discoveries in plant miRNA target recognition, e.g. it distinguishes translational and post-transcriptional inhibition, and it reports the number of small RNA/target site pairs that may affect small RNA binding activity to target transcript. The psRNATarget server is designed for high-throughput analysis of next-generation data with an efficient distributed computing back-end pipeline that runs on a Linux cluster. The server front-end integrates three simplified user-friendly interfaces to accept user-submitted or preloaded small RNAs and transcript sequences; and outputs a comprehensive list of small RNA/target pairs along with the online tools for batch downloading, key word searching and results sorting. The psRNATarget server is freely available at http://plantgrn.noble.org/psRNATarget/.

  6. Status of Beam Diagnostic Systems for the PEFP

    CERN Document Server

    Park Jang Ho; Choi Byung Ho; Ha Hwang Woon; Han, Sang-Hyo; Park, Sung-Ju; Woon Parc, Yong; Yun Huang Jung

    2005-01-01

    A proton linear accelerator is currently the construction at the KAERI (Korea Atomic Research Institute) to the PEFP (Proton Engineering Frontier Project) in Korea. We are accomplished the technique development of beam diagnostic system to be currently the construction. We treat beam diagnostics for the high power proton linear accelerator. Prototype beam position & phase monitor (BPPM) electronics was made and tested successfully in one of the beam diagnostic systems. The beam position monitor pickup electrode is a capacitive type (electrostatic type) which has a button form. Button form electrode, in common use around electron synchrotrons and storage rings, are a variant of the electrode with small button form (e.g., sub mm diameter). However, we are designed button form electrode to measure beam position of proton beam. The BCM (Beam Current Monitor) is developed Tuned CT (Current Transformer) for collaborate with Bergoz Instruments. This paper describes the status of beam diagnostic systems for the P...

  7. Superresolution beams

    CSIR Research Space (South Africa)

    Ngcobo, S

    2012-07-01

    Full Text Available stream_source_info Ngcobo2_2012.pdf.txt stream_content_type text/plain stream_size 3697 Content-Encoding ISO-8859-1 stream_name Ngcobo2_2012.pdf.txt Content-Type text/plain; charset=ISO-8859-1 SUPERRESOLUTION BEAMS S... University of Johannesburg, PO Box 524, Auckland Park, 2006, South Africa Slide 2 ? CSIR 2011 www.csir.co.za Outline ? Introduction ? Concept of superresolution beams ? Transformation of TEM00 to TEM10 ? Resonator...

  8. Superresolution beams

    CSIR Research Space (South Africa)

    Ngcobo, S

    2011-11-01

    Full Text Available stream_source_info Ngcobo3_2012.pdf.txt stream_content_type text/plain stream_size 4467 Content-Encoding ISO-8859-1 stream_name Ngcobo3_2012.pdf.txt Content-Type text/plain; charset=ISO-8859-1 SUPERRESOLUTION BEAMS S... 2011 www.csir.co.za Outline ? Introduction ? Concept of superresolution beams ? Transformation of TEM00 to TEM10 ? Resonator design and experimental setup ? Results ? Conclusions ? Future work Slide 3 ? CSIR 2011...

  9. The TDCpix readout ASIC: A 75ps resolution timing front-end for the NA62 Gigatracker hybrid pixel detector

    CERN Document Server

    Kluge, A; Bonacini, S; Jarron, P; Kaplon, J; Morel, M; Noy, M; Perktold, L; Poltorak, K

    2013-01-01

    The TDCpix is a novel pixel readout ASIC for the NA62 Gigatracker detector. NA62 is a new experiment being installed at the CERN Super Proton Synchrotron. Its Gigatracker detector shall provide on-beam tracking and time stamping of individual particles with a time resolution of 150 ps rms. It will consist of three tracking stations, each with one hybrid pixel sensor. The peak fl ow of particles crossing the detector modules reaches 1.27 MHz/mm 2 for a total rate of about 0.75 GHz. Ten TDCpix chips will be bump-bonded to every silicon pixel sensor. Each chip shall perform time stamping of 100 M particle hits per second with a detection ef fi ciency above 99% and a timing accuracy better than 200 ps rms for an overall three-station-setup time resolution of better than 150 ps. The TDCpix chip has been designed in a 130 nm CMOS technology. It will feature 45 40 square pixels of 300 300 μ m 2 and a complex End of Column peripheral region including an array of TDCs based on DLLs, four high speed serializers, a low...

  10. High-power vertical-cavity surface-emitting laser with an optimized p-contact diameter.

    Science.gov (United States)

    Zhang, Yan; Ning, Yongqiang; Qin, Li; Wang, Ye; Cui, Jinjiang; Liu, Guangyu; Zhang, Xing; Wang, Zhenfu; Sun, Yanfang; Liu, Yun; Wang, Lijun

    2010-07-01

    A 980 nm bottom-emitting vertical-cavity surface-emitting laser (VCSEL) with a p-contact diameter is reported to achieve high power and good beam quality. A numerical simulation is conducted on the current spreading in a VCSEL with oxidation between the active region and the p-type distributed Bragg reflector. It is found that, for a particular oxide aperture diameter, somewhat homogeneous current distribution can be achieved for a VCSEL with an optimized p-contact diameter. The far-field divergence angle from a 600 microm diameter VCSEL is suppressed from 30 degrees to 15 degrees, and no strong sidelobe is observed in the far-field pattern by using the optimized p-contact diameter. There is a slight rise in threshold and optical output power that is due to the p-contact optimization. By improving the device packaging method, the maximum optical output power of the device is 2.01 W.

  11. The role of a conserved membrane proximal cysteine in altering αPS2CβPS integrin diffusion

    Science.gov (United States)

    Syed, Aleem; Arora, Neha; Bunch, Thomas A.; Smith, Emily A.

    2016-12-01

    Cysteine residues (Cys) in the membrane proximal region are common post-translational modification (PTM) sites in transmembrane proteins. Herein, the effects of a highly conserved membrane proximal α-subunit Cys1368 on the diffusion properties of αPS2CβPS integrins are reported. Sequence alignment shows that this cysteine is palmitoylated in human α3 and α6 integrin subunits. Replacing Cys1368 in wild-type integrins with valine (Val1368) putatively blocks a PTM site and alters integrins’ ligand binding and diffusion characteristics. Both fluorescence recovery after photobleaching (FRAP) and single particle tracking (SPT) diffusion measurements show Val1368 integrins are more mobile compared to wild-type integrins. Approximately 33% and 8% more Val1368 integrins are mobile as measured by FRAP and SPT, respectively. The mobile Val1368 integrins also exhibit less time-dependent diffusion, as measured by FRAP. Tandem mass spectrometry data suggest that Cys1368 contains a redox or palmitoylation PTM in αPS2CβPS integrins. This membrane proximal Cys may play an important role in the diffusion of other alpha subunits that contain this conserved residue.

  12. Design of the New Wideband RF System for the CERN PS Booster

    CERN Document Server

    Paoluzzi, Mauro; Angoletta, Maria Elena; Arnaudon, Luca; Energico, Salvatore; Findlay, Alan; Haase, Matthias; Jaussi, Michael; Jones, Anthony; Landré, David; Molendijk, John; Quartullo, Danilo; Shaposhnikova, Elena

    2016-01-01

    For the renovation and upgrade of the CERN PS Booster (PSB) RF systems a development project was launched in 2012. The design, based on a new approach, aimed at replacing the existing tuned, narrowband RF systems with wideband, modular, solid-state driven units. A wide range of issues had to be addressed spanning from RF power production, radiation hardness of solid-state devices, active cancellation of beam-induced voltages, dedicated low-level electronics allowing multi-harmonic operation and beam stability. Following a three-year prototyping and testing campaign and two international reviews, the project endorsement came at the end of year 2015. It foresees the complete removal of present h1, h2 and h10 systems and the deployment of a new one covering all the frequency ranges from 1 MHz to 18 MHz. The four PSB rings will be equipped with 144 identical acceleration cells providing 24 kV total RF voltage per ring. This paper describes the design concepts, the retained solutions, the expected performances and...

  13. Completion systems for large diameter casing

    Energy Technology Data Exchange (ETDEWEB)

    Weinch, J.B.; Lorenz, M. (Baker Sand Control (US)); (Leggett, D. (Baker Sand Control Services Pta. Ltd. (SG)))

    1988-01-01

    Completion operations, for oil and gas wells, are usually performed in casing sizes not exceeding 13-3/8 in. (34.0 cm) with the majority of completions being performed in 9-5/8 in. (24.5 cm) and smaller. As such, the availability of completion equipment, for large diameter casings, becomes extremely limited or nonexistent. Occasionally, conditions may exist which require the completion to be designed in a casing size larger than 13-3/8 in. (34.0 cm). In order to complete in these casing sizes, special equipment must be designed. This paper discusses the design criteria, development, and subsequent use of perforating and gravel pack equipment generated for use in 20 in. (50.8 cm) casing.

  14. Fire protection covering for small diameter missiles

    Science.gov (United States)

    Riccitiello, S. R.; Sawko, P. M. (Inventor)

    1979-01-01

    Flexible intumescent protection sheeting of unusually uniform thickness were prepared from epoxy-polysulfide compositions, containing microfibers and the ammonium salt of 1,4-nitroaniline-2-sulfonic acid, as disclosed in U.S. Pat. No. 3,663,464, except that an ammonium salt particle size in the order of 5 to 8 microns and a fiber size of about 1/128th inch in length and 3 to 5 microns in diameter were found critical to obtain the required density of 1.46 to 1.50 g/cc. The insulation sheeting was prepared by a continuous process involving vacuum mixing, calendering, and curing under very strict conditions which depend to some extent upon the thickness of the sheet produced.

  15. Five meter diameter conical furlable antenna

    Science.gov (United States)

    Fortenberry, J. W.; Freeland, R. E.; Moore, D. M.

    1976-01-01

    An investigation was made to demonstrate that a 5-meter-diameter, furlable, conical reflector antenna utilizing a line source feed can be fabricated utilizing composite materials and to prove that the antenna can function mechanically and electrically as prototype flight hardware. The design, analysis, and testing of the antenna are described. An RF efficiency of 55% at 8.5 GHz and a surface error of 0.64 mm rms were chosen as basic design requirements. Actual test measurements yielded an efficiency of 53% (49.77 dB gain) and a surface error of 0.61 mm rms. Atmospherically induced corrosion of the reflector mesh resulted in the RF performance degradation. An assessment of the antenna as compared to the current state of the art technology was made. This assessment included cost, surface accuracy and RF performance, structural and mechanical characteristics, and possible applications.

  16. Laser synchrotron radiation and beam cooling

    Energy Technology Data Exchange (ETDEWEB)

    Esarey, E.; Sprangle, P.; Ting, A. [Naval Research Lab., Washington, DC (United States)] [and others

    1995-12-31

    The interaction of intense {approx_gt} 10{sup 18} W/cm{sup 2}, short pulse ({approx_lt} 1 ps) lasers with electron beams and plasmas can lead to the generation of harmonic radiation by several mechanisms. Laser synchrotron radiation may provide a practical method for generating tunable, near monochromatic, well collimated, short pulse x-rays in compact, relatively inexpensive source. The mechanism for the generation of laser synchrotron radiation is nonlinear Thomson scattering. Short wavelengths can be generated via Thomson scattering by two methods, (i) backscattering from relativistic electron beams, in which the radiation frequency is upshifted by the relativistic factor 4{gamma}{sup 2}, and (ii) harmonic scattering, in which a multitude of harmonics are generated with harmonic numbers extending out to the critical harmonic number nc{approx_equal}a{sub 0}{sup 3} {much_gt} 1, where a{sub 0} {approx_equal}10{sup -9}{lambda}I{sup 1/2}, {lambda} is the laser wavelength in {mu}m and I is the laser intensity in W/cm{sup 2}. Laser synchrotron sources are capable of generating short ({approx_lt} ps) x-ray pulses with high peak flux ({approx_gt} 10{sup 21} photons/s) and brightness ({approx_gt}{sup 19} photons/s-mm{sup 2}-mrad{sup 2} 0.1%BW. As the electron beam radiates via Thomson scattering, it can subsequently be cooled, i.e., the beam emittance and energy spread can be reduced. This cooling can occur on rapid ({approximately} ps) time scales. In addition, electron distributions with sufficiently small axial energy spreads can be used to generate coherent XUV radiation via a laser-pumped FEL mechanism.

  17. [Retinal Cell Therapy Using iPS Cells].

    Science.gov (United States)

    Takahashi, Masayo

    2016-03-01

    Progress in basic research, starting with the work on neural stem cells in the middle 1990's to embryonic stem (ES) cells and induced pluripotent stem (iPS) cells at present, will lead the cell therapy (regenerative medicine) of various organs, including the central nervous system to a big medical field in the future. The author's group transplanted iPS cell-derived retinal pigment epithelial (RPE) cell sheets to the eye of a patient with exudative age-related macular degeneration (AMD) in 2014 as a clinical research. Replacement of the RPE with the patient's own iPS cell-derived young healthy cell sheet will be one new radical treatment of AMD that is caused by cellular senescence of RPE cells. Since it was the first clinical study using iPS cell-derived cells, the primary endpoint was safety judged by the outcome one year after surgery. The safety of the cell sheet has been confirmed by repeated tumorigenisity tests using immunodeficient mice, as well as purity of the cells, karyotype and genetic analysis. It is, however, also necessary to prove the safety by clinical studies. Following this start, a good strategy considering cost and benefit is needed to make regenerative medicine a standard treatment in the future. Scientifically, the best choice is the autologous RPE cell sheet, but autologous cell are expensive and sheet transplantation involves a risky part of surgical procedure. We should consider human leukocyte antigen (HLA) matched allogeneic transplantation using the HLA 6 loci homozyous iPS cell stock that Prof. Yamanaka of Kyoto University is working on. As the required forms of donor cells will be different depending on types and stages of the target diseases, regenerative medicine will be accomplished in a totally different manner from the present small molecule drugs. Proof of concept (POC) of photoreceptor transplantation in mouse is close to being accomplished using iPS cell-derived photoreceptor cells. The shortest possible course for treatment

  18. A transmissão psíquica geracional

    Directory of Open Access Journals (Sweden)

    Vinícius Oliveira dos Santos

    Full Text Available O artigo seguinte refere-se a um estudo sobre como ocorre a transmissão psíquica entre as gerações e qual sua importância na constituição psíquica do sujeito. É também objetivo deste artigo explicar o que são as transmissões intergeracional e transgeracional. Para buscar respostas para essas questões, fez-se uma pesquisa bibliográfica sobre a transmissão psíquica, pelo viés psicanalítico, principalmente a partir da teoria lacaniana e com conceitos oriundos da linguística saussuriana. Será a partir de uma determinada ordem simbólica, constituída pela linguagem que precede o sujeito, nomeado por Lacan como o Outro, que a transmissão psíquica entre gerações ganhará o seu caráter unívoco, sempre se tendo em mente a importância fundamental do recalcamento e de seus efeitos, bem como do retorno do recalcado nas diferentes gerações. A transmissão psíquica é necessária e concomitante à constituição do sujeito, e ocorre através da linguagem, dos significantes que irão determinar uma ordem simbólica para o ser que nasce através dos diferentes discursos que perpassam as gerações nas figuras dos pais desse novo ser. Essa ordem simbólica continuará a se fazer presente nesse novo sujeito pelo restante de sua existência. Este artigo busca dar nova luz ao aspecto da transmissão psíquica transgeracional, diferenciando-se da recalque s abordagens psicanalíticas contemporâneas por ser uma leitura lacaniana. Serão usados dois exemplos: um de como a transmissão aparece na cultura, outro, na subjetividade do sujeito através da arte.

  19. Pink-beam serial crystallography

    Energy Technology Data Exchange (ETDEWEB)

    Meents, A; Wiedorn, M. O.; Srajer, V.; Henning, R.; Sarrou, I.; Bergtholdt, J.; Barthelmess, M.; Reinke, P.Y.A.; Dirksmeyer, D.; Tolstikova, A.; Schaible, S.; Messerschmidt, M.; Ogata, C. M.; Kissick, D. J.; Taft, M.H.; Manstein, D.J.; Lieske, J.; Oberthuer, D.; Fischetti, R. F.; Chapman, H. N.

    2017-11-03

    Serial X-ray crystallography allows macromolecular structure determination at 31 both X-ray Free Electron Lasers (XFELs) and, more recently, synchrotron 32 sources. The time resolution for serial synchrotron crystallography experiments 33 has been limited to millisecond time scales with monochromatic beams. The 34 polychromatic, “pink”, beam provides a more than two orders of magnitude 35 increased photon flux and hence allows accessing much shorter time scales in 36 diffraction experiments at synchrotron sources. Here we report the structure 37 determination of two different protein samples by merging pink beam diffraction 38 patterns from many crystals, each collected with a single 100 ps X-ray pulse 39 exposure per crystal using a setup optimized for very low scattering background. 40 In contrast to experiments with monochromatic radiation, data from only 50 41 crystals were required to obtain complete data sets. The high quality of the 42 diffraction data highlights the potential of this method for studying irreversible 43 reactions at sub-microsecond timescales using high-brightness X-ray facilities. 44

  20. Timing shifts due to NIF beam repointing

    Energy Technology Data Exchange (ETDEWEB)

    Koch, J

    2007-08-15

    Repointing a NIF beam to hit a target position off target chamber center (TCC) will introduce a timing shift due to changes in the light pathlength. This shift could be important for target experiment requirements even for targets placed at TCC, since beam timing test shots will place beams up to 15 mm off TCC in order to spatially separate them on foil targets. In particular, timing errors due to beam repointing need to be considered against the 30 ps RMS timing requirement. Since the repointing process will keep the beam passing through a fixed point in the final optics assembly (the conversion crystal) by tip/tilt adjustments of two turning mirrors (LM5 and LM7), the problem naturally divides into two parts: Timing offsets past the conversion crystal due to target positioning changes, and timing offsets behind the fixed point on the conversion crystal due to turning mirror adjustments. Timing offsets past the conversion crystal can be significant, but are trivial to calculate exactly; however, an exact calculation of timing offsets behind the fixed point on the conversion crystal would require a three-dimensional optomechanical raytrace model to be developed for every beamline, and this would be difficult and expensive. In this memo, I estimate the magnitude of timing offsets due to pathlength changes behind the conversion crystal by analysis of a worst-case model. I conclude that these timing offsets are insignificant compared with the current allocation in the 30 ps RMS timing requirement, and that more detailed raytrace modeling of individual beams is not necessary.

  1. O Trabalho Psíquico da Intersubjetividade

    Directory of Open Access Journals (Sweden)

    Maria Inês Assumpção Fernandes

    2003-01-01

    Full Text Available O presente trabalho procura refletir sobre o trabalho psíquico da intersubjetividade nos grupos. Trata-se de pensá-lo na relação com a ruptura de investimentos durante o processo de Transformação x Criação, em primeiro lugar. A partir desse ponto, discutiremos a relação entre Transformação, Trabalho e Dispositivo. Neste caso pensamos nas possibilidades de intervenção, refletindo sobre a intervenção inpidual e a intervenção grupal. A questão da Transmissão Psíquica entre gerações será focalizada, fundamentalmente, no que se refere aos tempos lógicos do recalque.

  2. Images of Christ's Saving Work in Ps.-Epiphanius' Homilies

    Directory of Open Access Journals (Sweden)

    H. F. Stander

    1997-12-01

    Full Text Available Images of Christ's Saving Work in Ps.-Epiphanius' Homilies. One cannot really speak of a systematic theology on the subject of atone-ment in the patristic writers. Frances Young once said that 'it is in fact impossible to categorize neatly the thought of the major patristic writers on the subject of atonement'. She adds that one cannot do justice to the range of motifs and images that are found in describing the saving and atoning work of Christ if we merely dismember 'systematic theologies' to illustrate common soteriological themes. One can only appreciate patristic views of atonement if one begins by recognizing the multifaceted unity of imagery that pervades the literature. This then is the goal of this article: to discuss the rich images which Ps: -Epiphanius uses to describe the atoning work of Christ.

  3. Magnetoelectric MnPS3 as a candidate for ferrotoroidicity

    Science.gov (United States)

    Ressouche, E.; Loire, M.; Simonet, V.; Ballou, R.; Stunault, A.; Wildes, A.

    2010-09-01

    We have revisited the magnetic structure of manganese phosphorus trisulfide MnPS3 using neutron diffraction and polarimetry. MnPS3 undergoes a transition toward a collinear antiferromagnetic order at 78 K. The resulting magnetic point-group breaks both the time reversal and the space inversion thus allowing a linear magnetoelectric coupling. Neutron polarimetry was subsequently used to prove that this coupling provides a way to manipulate the antiferromagnetic domains simply by cooling the sample under crossed magnetic and electrical fields, in agreement with the nondiagonal form of the magnetoelectric tensor. In addition, this tensor has, in principle, an antisymmetric part that results in a toroidic moment and provides with a pure ferrotoroidic compound.

  4. PS Dreyer: Bakens op die pad van die wetenskap

    Directory of Open Access Journals (Sweden)

    A. J. Antonites

    1986-01-01

    Full Text Available PS Dreyer: Beacons on the path of science Professor PS Dreyer is an academic who has shown insight and vision into several problems of the human sciences since 1951. He has identified problems, but also contributed solutions to them. In this respect his philosophy on causality and freedom is of utmost importance. The same applies to his investigations into the relationship history-Christianity as well as the unity of sciences and how the concepts scientific, unscientic and nonscientific are related to one another. His contribution to the understanding of Greek philosophy should be of significance for time to come. Two milestones could be distinguished: Dreyer's particular solution to the problem of the criterion on truth, viz meaningfulness and his notion of the knowledge of values in ethics by valuation in contradistinction to knowledge through feeling, reason and will.

  5. Images of Christ's Saving Work in Ps.-Epiphanius' Homilies

    Directory of Open Access Journals (Sweden)

    H. F. Stander

    1997-01-01

    Full Text Available Images of Christ's Saving Work in Ps.-Epiphanius' Homilies. One cannot really speak of a systematic theology on the subject of atone-ment in the patristic writers. Frances Young once said that 'it is in fact impossible to categorize neatly the thought of the major patristic writers on the subject of atonement'. She adds that one cannot do justice to the range of motifs and images that are found in describing the saving and atoning work of Christ if we merely dismember 'systematic theologies' to illustrate common soteriological themes. One can only appreciate patristic views of atonement if one begins by recognizing the multifaceted unity of imagery that pervades the literature. This then is the goal of this article: to discuss the rich images which Ps: -Epiphanius uses to describe the atoning work of Christ.

  6. Monte Carlo simulations of nanoscale focused neon ion beam sputtering.

    Science.gov (United States)

    Timilsina, Rajendra; Rack, Philip D

    2013-12-13

    A Monte Carlo simulation is developed to model the physical sputtering of aluminum and tungsten emulating nanoscale focused helium and neon ion beam etching from the gas field ion microscope. Neon beams with different beam energies (0.5-30 keV) and a constant beam diameter (Gaussian with full-width-at-half-maximum of 1 nm) were simulated to elucidate the nanostructure evolution during the physical sputtering of nanoscale high aspect ratio features. The aspect ratio and sputter yield vary with the ion species and beam energy for a constant beam diameter and are related to the distribution of the nuclear energy loss. Neon ions have a larger sputter yield than the helium ions due to their larger mass and consequently larger nuclear energy loss relative to helium. Quantitative information such as the sputtering yields, the energy-dependent aspect ratios and resolution-limiting effects are discussed.

  7. High energy density plasma science with an ultrarelativistic electron beam

    Science.gov (United States)

    Joshi, C.; Blue, B.; Clayton, C. E.; Dodd, E.; Huang, C.; Marsh, K. A.; Mori, W. B.; Wang, S.; Hogan, M. J.; O'Connell, C.; Siemann, R.; Watz, D.; Muggli, P.; Katsouleas, T.; Lee, S.

    2002-05-01

    An intense, high-energy electron or positron beam can have focused intensities rivaling those of today's most powerful laser beams. For example, the 5 ps (full-width, half-maximum), 50 GeV beam at the Stanford Linear Accelerator Center (SLAC) at 1 kA and focused to a 3 micron rms spot size gives intensities of >1020 W/cm-2 at a repetition rate of >10 Hz. Unlike a ps or fs laser pulse which interacts with the surface of a solid target, the particle beam can readily tunnel through tens of cm of steel. However, the same particle beam can be manipulated quite effectively by a plasma that is a million times less dense than air! This is because of the incredibly strong collective fields induced in the plasma by the Coulomb force of the beam. The collective fields in turn react back onto the beam leading to many clearly observable phenomena. The beam paraticles can be: (1) Deflected leading to focusing, defocusing, or even steering of the beam; (2) undulated causing the emission of spontaneous betatron x-ray radiation and; (3) accelerated or decelerated by the plasma fields. Using the 28.5 GeV electron beam from the SLAC linac a series of experiments have been carried out that demonstrate clearly many of the above mentioned effects. The results can be compared with theoretical predictions and with two-dimensional and three-dimensional, one-to-one, particle-in-cell code simulations. These phenomena may have practical applications in future technologies including optical elements in particle beam lines, synchrotron light sources, and ultrahigh gradient accelerators.

  8. Design study of the large hadron electron collider and a rapid cycling synchrotron as alternative to the PS booster upgrade at CERN

    Energy Technology Data Exchange (ETDEWEB)

    Fitterer, Miriam

    2013-02-22

    With the Large Hadron Collider (LHC) the exploration of particle physics at center of mass energies at the TeV scale has begun. To extend the discovery potential of the LHC, a major upgrade is foreseen around 2020 of the LHC itself and the LHC injectors - the chain of accelerators preparing the beam for the LHC. One of the injectors - the second one in the chain - is the Proton Synchrotron (PS) Booster. Its performance is currently limited by the space-charge effect, which is the effect of the electromagnetic field of the particle beam on itself. This effect becomes weaker with higher energy, and therefore an energy upgrade of the PS Booster to 2 GeV maximum beam energy is foreseen. As the PS Booster is with its 40 years already an old machine, the construction of a new accelerator, a Rapid Cycling Synchrotron (RCS), to replace the PS Booster has been proposed. In this thesis different options for the beam guidance in the RCS - referred to as lattice and optics - are studied, followed by a more general comparison of different lattices and optics and their performance under consideration of the space-charge effect. To further complement the LHC physics program, also the possibility of deep inelastic lepton-nucleon scattering at the LHC has been suggested, referred to as Large Hadron Electron Collider (LHeC). In this case the proton beam of the LHC collides with the electron beam, which is accelerated in a separate newly built machine. Two options are considered as electron accelerator: a new energy recovery linac - the Linac-Ring option - and the installation of an electron ring in the existing LHC tunnel - the Ring-Ring option. One of the main challenges of the Ring-Ring option is the integration of the electron ring in the current LHC tunnel. A layout, lattice and optics of the electron accelerator is developed in this thesis, which meets the requirements with regard to integration and reaches the beam parameters demanded by the particle physics experiments.

  9. Functional characterization of calcineurin homologs PsCNA1/PsCNB1 in Puccinia striiformis f. sp. tritici using a host-induced RNAi system.

    Directory of Open Access Journals (Sweden)

    Hong Zhang

    Full Text Available Calcineurin plays a key role in morphogenesis, pathogenesis and drug resistance in most fungi. However, the function of calcineurin genes in Puccinia striiformis f. sp. tritici (Pst is unclear. We identified and characterized the calcineurin genes PsCNA1 and PsCNB1 in Pst. Phylogenetic analyses indicate that PsCNA1 and PsCNB1 form a calcium/calmodulin regulated protein phosphatase belonging to the calcineurin heterodimers composed of subunits A and B. Quantitative RT-PCR analyses revealed that both PsCNA1 and PsCNB1 expression reached their maximum in the stage of haustorium formation, which is one day after inoculation. Using barely stripe mosaic virus (BSMV as a transient expression vector in wheat, the expression of PsCNA1 and PsCNB1 in Pst was suppressed, leading to slower extension of fungal hyphae and reduced production of urediospores. The immune-suppressive drugs cyclosporin A and FK506 markedly reduced the germination rates of urediospores, and when germination did occur, more than two germtubes were produced. These results suggest that the calcineurin signaling pathway participates in stripe rust morphogenetic differentiation, especially the formation of haustoria during the early stage of infection and during the production of urediospores. Therefore PsCNA1 and PsCNB1 can be considered important pathogenicity genes involved in the wheat-Pst interaction.

  10. Consolidation of the 45-Year Old PS Main Magnet System

    CERN Document Server

    Zickler, Thomas; Kalbreier, Wilhelm; Mess, Karl Hubert; Newborough, Antony

    2006-01-01

    After a major coil insulation breakdown on two of the 47-year-old CERN PS main magnets in 2003, an extensive magnet consolidation program has been launched. This article reviews the analysis of the magnet state be-fore the repair and the applied major improvements. An overview is given of the production of the new compo-nents, the actual refurbishment and the commissioning of the main magnet system after 18 months shutdown.

  11. Science spin: iPS cell research in the news.

    Science.gov (United States)

    Caulfield, T; Rachul, C

    2011-05-01

    Big scientific developments have always been spun to meet particular social agendas. We have seen it in the context of global warming, nuclear power, and genetically modified organisms. But few stories illustrate the phenomenon of spin as well as the reaction, and concomitant media coverage, that surrounded the November 2007 announcement regarding the reprogramming of skin cells to produce cells with qualities comparable to those of human embryonic stem cells (hESCs) known as induced pluripotent stem (iPS) cells.

  12. Ps18.pdf | sep2002 | jess | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; jess; sep2002; Ps18.pdf. 404! error. The page your are looking for can not be found! Please check the link or use the navigation bar at the top. YouTube; Twitter; Facebook; Blog. Academy News. IAS Logo. Associates – 2017. Posted on 17 July 2017. Click here to see the list · 28th Mid Year Meeting. Posted on 26 May ...

  13. Specialty flat-top beam delivery fibers with controlled beam parameter product

    Science.gov (United States)

    Jollivet, C.; Farley, K.; Conroy, M.; Abramczyk, J.; Belke, S.; Becker, F.; Tankala, K.

    2016-03-01

    Beam delivery fibers have been used widely for transporting the optical beams from the laser to the subject of irradiation in a variety of markets including industrial, medical and defense applications. Standard beam delivery fibers range from 50 to 1500 μm core diameter and are used to guide CW or pulsed laser light, generated by solid state, fiber or diode lasers. Here, we introduce a novel fiber technology capable of simultaneously controlling the beam profile and the angular divergence of single-mode (SM) and multi-mode (MM) beams using a single-optical fiber. Results of beam transformation from a SM to a MM beam with flat-top intensity profile are presented in the case of a controlled BPP at 3.8 mm*mrad. The scaling capabilities of this flat-top fiber design to achieve a range of BPP values while ensuring a flat-top beam profile are discussed. In addition, we demonstrate, for the first time to the best of our knowledge, the homogenizer capabilities of this novel technology, able to transform random MM beams into uniform flat-top beam profiles with very limited impact on the beam brightness. This study is concluded with a discussion on the scalability of this fiber technology to fit from 50 up to 1500 μm core fibers and its potential for a broader range of applications.

  14. Development of large diameter carbon monofilament

    Science.gov (United States)

    Jacob, B.; Neltri, R. D.

    1973-01-01

    A process for preparing large diameter carbon-boron monofilament was developed. The process involves chemical vapor depositing a carbon-boron alloy monofilament from a BCl3, CH4, and H2 gas mixture onto a carbon substrate. Amorphous alloys were formed when gaseous mixtures containing greater than 20 percent methane (80 percent BCl3) were used. The longest uninterrupted lengths of carbon-boron monofilament were produced using a CH4/BCl3 gas ratio of 2.34. It was found that the properties of the carbon-boron alloy monofilament improved when the carbon substrate was precleaned in chlorine. The highest strength monofilament was attained when a CH4/BCl3 gas volume ratio of 0.44 was 28 million N/sq cm (40 million psi). While the highest strengths were attained in this run, the 0.44 gas ratio and other CH4/BCl3 ratios less than 2.34 would not yield long runs. Runs using these ratios were usually terminated because of a break in the monofilament within the reactor. It is felt better process control could probably be achieved by varying the amount of hydrogen; the BCl3/H2 ratio was kept constant in these studies.

  15. Study and design of beam expander with wide aperture

    Science.gov (United States)

    Guo, Ming; Jin, Guangyong; Cai, Jixing; Zhang, Wei; Wei, Zhi

    2014-12-01

    In order to improve the capacity of beam collimation for laser beam expander, it is necessary to design a more reasonable and feasible structure of beam expander system. Laser beam expander is used to compress the laser divergence angle, in order to reduce the energy losing in long distance scanning acquisition system. This paper introduces the working principle and design idea of the laser beam expander, the collimating multiplying power focal length and the collimated magnification formula of expander main, secondary mirror. According to the third-order aberration theory, Considering the spherical aberration, sine difference and divergence angle, the reasonable analysis of optical path, ZEMAX optical design software was used to design large-diameter laser beam expander and analysis and optimize, And given the actual design data and results. Display the maximum optical path difference is +/-0.01λ of the main light ray and each light ray. To combination the rear- group objective lens of Galileo and Kepler beam expander, a large-diameter(1.475m) laser beam expander was designed with 0.2m in the diameter, 1/2m in the relative caliber. In the objective lens System, a high-order aspherical was used to the aberration of extra-axial point. we can see that the image quality is close to the diffraction limit from the curves of wavefront. In addition to improve image quality effectively, the system has the characteristics of simple structure, less costly and less design difficulty to compare with the other beam expanding system. And make the output beam's divergence angle smaller, energy density higher, and the beam quality has been greatly improved. The results show that the beam expander is fully meet the design requirements, the use effect is good. Design and research of laser beam expanding system not only improves the quality of the laser beam in the laser system, but also enlarge the application field of laser technology in photoelectric system.

  16. Digital Beam Trajectory and Orbit System, for the CERN Proton Synchrotron

    CERN Document Server

    Kasprowicz, G; Raich, U

    2008-01-01

    A new trajectory and orbit measurement system using fast signal sampling and digital signal processing in an FPGA is proposed for the CERN PS. The system uses a constant sampling frequency while the beam revolution frequency changes during acceleration. Synchronization with the beam is accomplished through a numerical PLL algorithm. This algorithm is also capable of treating RF gymnastics like bunch splitting or batch compression with the help of external timing signals. Baseline and position calculation are provided in the FPGA code as well. After having implemented the algorithms in C and MatLab and tested them with data from a test run at the PS, they have now been implemented in the FPGA for online use. Results of measurements on a single beam position monitor in the CERN PS and the SIS-18 at GSI will be presented.

  17. Metallic beryllium-7 target of small diameter

    CERN Document Server

    Zyuzin, A Yu; Vincent, J S; Buckley, K R; Bateman, N P; Snover, K A; Csandjan, J M; Steiger, T D; Adelberger, E G; Swanson, H E

    1999-01-01

    The stellar sup 7 Be(p, gamma) sup 8 B reaction rate has the largest uncertainty among all nuclear reaction rates in the standard solar model. However, the solar neutrino flux predicted for the majority of proposed and existing solar neutrino detectors is directly dependent on the rate of sup 7 Be(p, gamma) sup 8 B reaction. The existing solar neutrino detectors measure rate of sup 8 B decay neutrinos that is too low. This constitutes largely the solar neutrino problem. Existing measurements of the sup 7 Be(p, gamma) sup 8 B reaction rate disagree with one another, indicating the need for more precise experiments. To provide the required targets a new procedure for sup 7 Be production, separation and target manufacturing has been developed. First, a lithium target has been designed for sup 7 Be production at TRIUMF's 13 MeV cyclotron. The lithium target has been extensively tested at 50 mu A proton beam current yielding 8.1 MBq/mu A h of sup 7 Be. An adsorption filtration technique has been developed for sup ...

  18. Toroidal runaway beams.

    Science.gov (United States)

    Fussmann, G

    2013-01-01

    We investigate the dynamics of a special group of runaway electrons which possibly play an important role in toroidal fusion devices. Starting from the torus center they are accelerated by a toroidal electric field and are hence forced to move across the toroidal magnetic field into regions with rising poloidal field in order to compensate for the centrifugal forces. Can such particles finally form a tight beam of relativistic runaways in the outboard region or is this prevented due to the perpendicular momentum they gain by passing the toroidal field? Since neither the energy nor the magnetic momentum of the particles is conserved this question has been treated by invoking the relativistic equations of motion. It turns out, however, that the problem can be essentially simplified since, apart from the centrifugal forces associated with the toroidal motion, the inertia forces are negligible. The resulting first order equation can be solved analytically. From the solution it is concluded that the formation of narrow runaway beams with diameters in the range of micrometers and very small pitch angles (v(perpendicular)/v(||)<10(-6)) appears feasible. Such electrons would perform low-frequency oscillations about three to four orders of magnitude lower than the gyrofrequency in the toroidal field. When passing the maximum poloidal magnetic field strength they are suddenly lost from the plasma region.

  19. Fiber optic picosecond laser pulse transmission line for hydrogen ion beam longitudinal profile measurement.

    Science.gov (United States)

    Huang, Chunning; Liu, Yun; Aleksandrov, Alexander

    2013-07-01

    We present a fiber optic laser pulse transmission line for nonintrusive longitudinal profile measurement of the hydrogen ion (H(-)) beam at the front-end of the Spallation Neutron Source accelerator. The 80.5 MHz, 2.5 ps, multikilowatt optical pulses are delivered to the accelerator beam line through a large-mode-area polarization-maintaining optical fiber to ensure high measurement stability. The transmission efficiency, output laser beam quality, pulse jitter, and pulse width broadening over a 30 m long fiber line are experimentally investigated. A successful measurement of the H(-) beam microbunch (~130 ps) profile is obtained. The experiment is the first demonstration to our knowledge of particle beam profile diagnostics using a fiber optic laser pulse transmission line.

  20. Modified M20 Beam Position Monitor Testing

    Science.gov (United States)

    Koros, Jessica; Musson, John

    2017-09-01

    Beam position monitors (BPMs) are used to measure lateral beam position. Two pairs of modified wire BPMs are being evaluated for installation into the injector at Jefferson Lab (JLab). The BPMs were coated with a Non-Evaporable Getter (NEG) to aid in pumping at the electron gun, as an ultra-high vacuum is required to protect the gun and to avoid scattering the beam. Beam in the injector has a large diameter, allowing extraction of second moments to give information about beam profile and emittance. The purpose of this project is to determine the effects of NEG coating on the BPMs and to calculate second moments from beam models on the Goubau Line (G-Line). Using the G-Line, scans of the BPMs were taken before and after NEG coating. Each scan produced an electrical field map, which characterizes properties of the BPM, including scale factors and coupling. Second moments were calculated using superposition of previous scan data, and verification of this method was attempted using several beam models. Results show the BPMs responded well to NEG and that measurement of second moments is possible. Once the BPMs are installed, they will enhance gun vacuum and enable monitoring of shape and trajectory of the beam as it exits the electron gun to ensure quality beam for experiments. This work is made possible through support from NSF award 1659177 to Old Dominion University.

  1. Kultuur isiksuse psühholoogiat ei mõjuta / Tiit Kändler

    Index Scriptorium Estoniae

    Kändler, Tiit, 1948-

    2010-01-01

    Psühholoogia uuemate andmete kohaselt ei sõltu indiviidi seadumus kultuurist, soost, vanusest, haridusest. Eesti psühholoogide Jüri Alliku ja Ann Realo osalusel ajakirjas "Journal Personality and Social Psychology" ilmunud artiklist

  2. Kultuur isiksuse psühholoogiat ei mõjuta / Tiit Kändler

    Index Scriptorium Estoniae

    Kändler, Tiit, 1948-

    2005-01-01

    Psühholoogia uuemate andmete kohaselt ei sõltu indiviidi seadumus kultuurist, soost, vanusest, haridusest. Eesti psühholoogide Jüri Alliku ja Anu Realo osalusel ajakirjas "Journal Personality and Social Psychology" ilmunud artiklist

  3. Comparative, validity and responsiveness of the HOOS-PS and KOOS-PS to the WOMAC physical function subscale in total joint replacement for osteoarthritis

    DEFF Research Database (Denmark)

    Davis, A M; Perruccio, A V; Canizares, M

    2009-01-01

    OBJECTIVE: To evaluate the internal consistency of the Hip disability and Osteoarthritis Outcome Score-Physical Function Short-form (HOOS-PS) and the Knee injury and Osteoarthritis Outcome Score-Physical Function Short-form (KOOS-PS) in total hip replacement (THR) and total knee (TKR) replacement....... Construct validity and responsiveness were compared to the Western Ontario McMaster Universities' Osteoarthritis Index (WOMAC) Likert 3.0 physical function (PF) subscale and the PF excluding the items in the short measures (PF-exclusions). METHODS: Participants completed the full HOOS or KOOS, measures...... of fatigue, anxiety, depression and the Chronic Pain Grade (CPG) pre-surgery and the HOOS or KOOS 6 months post-surgery. Internal consistency for the HOOS-PS and KOOS-PS was calculated using Cronbach's alpha. For construct validity, it was hypothesized that correlations between the HOOS-PS or KOOS-PS and PF...

  4. Analüütilised voolud psühholoogias ja nende rakendamine pedagoogikas / Aleksander Elango

    Index Scriptorium Estoniae

    Elango, Aleksander, 1902-2004

    2001-01-01

    Analüütise psühholoogia kolm koolkonda - S.Freudì koolkond e. päris-psühhoanalüüs, A.Adlerì koolkond e. individuaalpsühholoogia ja C.G.Jungì psühhoanalüüsi ja individuaalpsühholoogia sünteesi luua püüdev koolkond. Analüütise psühholoogia koolkondade ja pedagoogika suhetest

  5. Changes in optical properties of polystyrene thin films by proton beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Sung Hyun; Jung, Jin Mook; Choi, Jae Hak [Dept. of of Polymer Science and Engineering, Chungnam National University, Daejeon (Korea, Republic of); Jung, Chan Hee; Hwang, In Tae; Shin, Jun Hwa [Research Division for Industry and Environment, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup(Korea, Republic of)

    2017-06-15

    In this study, changes in optical properties of polystyrene (PS) thin films by proton irradiation were investigated. PS thin films were irradiated with 150 keV proton ions at fluences ranging from 1 × 10{sup 15} to 1 × 10{sup 16} ions cm{sup -2}. The chemical structures and optical properties of proton beam-irradiated PS thin films were investigated by using a FT-IR spectrometer, an UVvis spectrophotometer, a photoluminescence (PL) and a fluorescence microscope. The results of the chemical structure analysis revealed that chemical functional groups, such as OH, C=O, and C=C, were formed in the PS films due to the oxidation and formation of carbon clusters by proton beam irradiation. The PL emission was generated and gradually red-shifted with an increasing fluence due to the higher formation of sp2 carbon clusters by proton beam irradiation. The highest PL intensity was obtained at a fluence of 5×10{sup 15} ions cm{sup -2}. The optical band gap of PS calculated by using a Tauc’s plot decreased with increasing the fluence due to the formation of sp2 carbon clusters by proton beam irradiation.

  6. Physics at the AD/PS/SPS (3/4)

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    Lecture 3: Flavour and Neutrinos The CERN SPS provides kaon and neutrino beams which are unique in the world. The lecture will describe the flavour and neutrino research conducted with these beams. The flavour programme is centered around the study of kaons. It includes a broad spectrum of topics such as CP-Violation, the precise determination of quark-mixing parameters, lepton universality and very rare decays. The CNGS neutrino beam enables to perform long baseline neutrino oscillation experiments with unique features such as the tau lepton appearance.

  7. Shiitake mushroom production on small diameter oak logs in Ohio

    Science.gov (United States)

    S.M. Bratkovich

    1991-01-01

    Yields of different strains of shiitake mushrooms (Lentinus edodes) were evaluated when produced on small diameter oak logs in Ohio. Logs averaging between 3-4 inches in diameter were inoculated with four spawn strains in 1985.

  8. Body diameters in 3 - 6 years old children from Plovdiv

    Directory of Open Access Journals (Sweden)

    Tineshev Slavi

    2013-01-01

    Full Text Available The purpose of the research is to analyze the body diameters in 3-6 year old children. The biacromial diameters were taken as well as the two chest diameters, the bicristal and bitrohanterial diameters in 316 children (157 boys and 159 girls 3, 4, 5 and 6 years of age attending kindergarten in Plovdiv. The analysis shows that all diameters, with the exception of the bitrohanterial have higher values in boys. The absolute year's increment of the diameters is greater in girls. The growth velocity of the researched features is greatest at the age of 3-4 and 4-5, decreasing at different rates for the different features at the age of 5-6. The only exception is the sagittal chest diameter in both sexes and the bitrohanterial diameters in girls.

  9. File list: His.PSC.05.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.05.AllAg.iPS_cells hg19 Histone Pluripotent stem cell iPS cells SRX317576,S...077,SRX317607 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.PSC.05.AllAg.iPS_cells.bed ...

  10. File list: His.PSC.50.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.50.AllAg.iPS_cells mm9 Histone Pluripotent stem cell iPS cells SRX977417,SR...RX127376,SRX146530,SRX146522,SRX146547,SRX333561,SRX035985,SRX1090869 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.PSC.50.AllAg.iPS_cells.bed ...

  11. File list: ALL.PSC.50.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.50.AllAg.iPS_cells hg19 All antigens Pluripotent stem cell iPS cells SRX088...16,SRX189400,SRX189399 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/ALL.PSC.50.AllAg.iPS_cells.bed ...

  12. File list: His.PSC.10.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.10.AllAg.iPS_cells hg19 Histone Pluripotent stem cell iPS cells SRX110016,S...315,SRX381309 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.PSC.10.AllAg.iPS_cells.bed ...

  13. File list: ALL.PSC.20.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.20.AllAg.iPS_cells hg19 All antigens Pluripotent stem cell iPS cells SRX088...27,SRX189400,SRX189399 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/ALL.PSC.20.AllAg.iPS_cells.bed ...

  14. File list: His.PSC.50.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.50.AllAg.iPS_cells hg19 Histone Pluripotent stem cell iPS cells SRX110015,S...079,SRX317585 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.PSC.50.AllAg.iPS_cells.bed ...

  15. File list: Pol.PSC.20.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.PSC.20.AllAg.iPS_cells mm9 RNA polymerase Pluripotent stem cell iPS cells SRX97...7435,SRX977434,SRX027462 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.PSC.20.AllAg.iPS_cells.bed ...

  16. File list: ALL.PSC.05.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.05.AllAg.iPS_cells hg19 All antigens Pluripotent stem cell iPS cells SRX753...00,SRX189399,SRX317607 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/ALL.PSC.05.AllAg.iPS_cells.bed ...

  17. File list: Pol.PSC.10.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.PSC.10.AllAg.iPS_cells mm9 RNA polymerase Pluripotent stem cell iPS cells SRX97...7435,SRX977434,SRX027462 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.PSC.10.AllAg.iPS_cells.bed ...

  18. File list: ALL.PSC.05.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.05.AllAg.iPS_cells mm9 All antigens Pluripotent stem cell iPS cells SRX9774...30,SRX146524,SRX146522,SRX146547 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.PSC.05.AllAg.iPS_cells.bed ...

  19. File list: Oth.PSC.50.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.PSC.50.AllAg.iPS_cells mm9 TFs and others Pluripotent stem cell iPS cells SRX97...RX146524 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.PSC.50.AllAg.iPS_cells.bed ...

  20. File list: Pol.PSC.50.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.PSC.50.AllAg.iPS_cells mm9 RNA polymerase Pluripotent stem cell iPS cells SRX97...7435,SRX977434,SRX027462 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.PSC.50.AllAg.iPS_cells.bed ...

  1. File list: DNS.PSC.20.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.PSC.20.AllAg.iPS_cells hg19 DNase-seq Pluripotent stem cell iPS cells SRX040379...,SRX040378,SRX135563,SRX040377,SRX040376,SRX189427,SRX189400,SRX189399 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.PSC.20.AllAg.iPS_cells.bed ...

  2. File list: DNS.PSC.10.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.PSC.10.AllAg.iPS_cells hg19 DNase-seq Pluripotent stem cell iPS cells SRX040379...,SRX040378,SRX040377,SRX040376,SRX135563,SRX189427,SRX189400,SRX189399 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.PSC.10.AllAg.iPS_cells.bed ...

  3. File list: Pol.PSC.05.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.PSC.05.AllAg.iPS_cells mm9 RNA polymerase Pluripotent stem cell iPS cells SRX97...7435,SRX027462,SRX977434 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.PSC.05.AllAg.iPS_cells.bed ...

  4. File list: ALL.PSC.10.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.10.AllAg.iPS_cells hg19 All antigens Pluripotent stem cell iPS cells SRX753...09,SRX189400,SRX189399 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/ALL.PSC.10.AllAg.iPS_cells.bed ...

  5. File list: His.PSC.10.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.10.AllAg.iPS_cells mm9 Histone Pluripotent stem cell iPS cells SRX977417,SR...RX127372,SRX1090869,SRX127376,SRX035977,SRX146530,SRX146547,SRX146522 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.PSC.10.AllAg.iPS_cells.bed ...

  6. File list: Oth.PSC.20.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.PSC.20.AllAg.iPS_cells mm9 TFs and others Pluripotent stem cell iPS cells SRX97...RX146524 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.PSC.20.AllAg.iPS_cells.bed ...

  7. File list: DNS.PSC.05.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.PSC.05.AllAg.iPS_cells hg19 DNase-seq Pluripotent stem cell iPS cells SRX040379...,SRX040378,SRX040377,SRX040376,SRX135563,SRX189427,SRX189400,SRX189399 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.PSC.05.AllAg.iPS_cells.bed ...

  8. File list: His.PSC.20.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.20.AllAg.iPS_cells mm9 Histone Pluripotent stem cell iPS cells SRX127389,SR...RX127372,SRX127373,SRX1090869,SRX127376,SRX146530,SRX146522,SRX146547 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.PSC.20.AllAg.iPS_cells.bed ...

  9. Genomic imprinting is variably lost during reprogramming of mouse iPS cells.

    Science.gov (United States)

    Takikawa, Sachiko; Ray, Chelsea; Wang, Xin; Shamis, Yulia; Wu, Tien-Yuan; Li, Xiajun

    2013-09-01

    Derivation of induced pluripotent stem (iPS) cells is mainly an epigenetic reprogramming process. It is still quite controversial how genomic imprinting is reprogrammed in iPS cells. Thus, we derived multiple iPS clones from genetically identical mouse somatic cells. We found that parentally inherited imprint was variably lost among these iPS clones. Concurrent with the loss of DNA methylation imprint at the corresponding Snrpn and Peg3 imprinted regions, parental origin-specific expression of the Snrpn and Zim1 imprinted genes was also lost in these iPS clones. This loss of parental genomic imprinting in iPS cells was likely caused by the reprogramming process during iPS cell derivation because extended culture of iPS cells did not lead to significant increase in the loss of genomic imprinting. Intriguingly, one to several paternal chromosomes appeared to have acquired de novo methylation at the Snrpn and Zac1 imprinted regions in a high percentage of iPS clones. These results might have some implications for future therapeutic applications of iPS cells. Since DNA methylation imprint can be completely erased in some iPS clones at multiple imprinted regions, iPS cell reprogramming may also be employed to dissect the underlying mechanisms of erasure, reacquisition and maintenance of genomic imprinting in mammals. Copyright © 2013. Published by Elsevier B.V.

  10. File list: Oth.PSC.10.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.PSC.10.AllAg.iPS_cells mm9 TFs and others Pluripotent stem cell iPS cells SRX65...RX146524 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.PSC.10.AllAg.iPS_cells.bed ...

  11. File list: His.PSC.05.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.05.AllAg.iPS_cells mm9 Histone Pluripotent stem cell iPS cells SRX977417,SR...RX127374,SRX127373,SRX1090869,SRX333561,SRX146530,SRX146522,SRX146547 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.PSC.05.AllAg.iPS_cells.bed ...

  12. File list: ALL.PSC.10.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.10.AllAg.iPS_cells mm9 All antigens Pluripotent stem cell iPS cells SRX9774...30,SRX146524,SRX146547,SRX146522 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.PSC.10.AllAg.iPS_cells.bed ...

  13. File list: ALL.PSC.50.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.50.AllAg.iPS_cells mm9 All antigens Pluripotent stem cell iPS cells SRX9773...1,SRX035985,SRX1090869 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.PSC.50.AllAg.iPS_cells.bed ...

  14. File list: ALL.PSC.20.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.PSC.20.AllAg.iPS_cells mm9 All antigens Pluripotent stem cell iPS cells SRX9773...30,SRX146522,SRX146547 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.PSC.20.AllAg.iPS_cells.bed ...

  15. File list: His.PSC.20.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.PSC.20.AllAg.iPS_cells hg19 Histone Pluripotent stem cell iPS cells SRX110015,S...315,SRX381309 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.PSC.20.AllAg.iPS_cells.bed ...

  16. File list: Oth.PSC.05.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.PSC.05.AllAg.iPS_cells mm9 TFs and others Pluripotent stem cell iPS cells SRX65...RX146524 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.PSC.05.AllAg.iPS_cells.bed ...

  17. File list: DNS.PSC.50.AllAg.iPS_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.PSC.50.AllAg.iPS_cells hg19 DNase-seq Pluripotent stem cell iPS cells SRX040379...,SRX040378,SRX135563,SRX040376,SRX040377,SRX189427,SRX189400,SRX189399 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.PSC.50.AllAg.iPS_cells.bed ...

  18. A new SPM at Fudan university. System construction and calculation of beam optics

    CERN Document Server

    Liu Bo; Sun Min De; Shi Xian Feng; Sun Chuan Chen; Shen Hao; Mi Yong

    2002-01-01

    High Energy ion beams accelerated by the tandem (9SDH-2) can be focused to a beam diameter about 1 mu m by quadrupole triplet magnetic lens. The detection system consists of several detectors. Several ion beam analytical techniques, such as PIXE, RBS, STIM, etc. are available with the new SPM system. The facility can promote interdisciplinary researches of different fields including material science, environment science, geology and biology. In order to minimize the diameter of the ion beam, a simulation calculation of beam optics is carried out for the new SPM system. The calculation results are helpful to the installation of the whole microbeam system

  19. Ser-261 phospho-regulation is involved in pS256 and pS269-mediated aquaporin-2 apical translocation.

    Science.gov (United States)

    Yui, Naofumi; Ando, Fumiaki; Sasaki, Sei; Uchida, Shinichi

    2017-08-26

    Vasopressin catalyzes aquaporin-2 phosphorylation at several serine sites in the C-terminal region. Compared with Ser-256 and Ser-269 phosphorylation, the role of Ser-261 phospho-regulation on vasopressin-regulated AQP2 apical translocation is largely unknown. In addition, recent discovery of transcytotic apical delivery of AQP2 made the concept of its intracellular trafficking even more complicated. In this study, we evaluated how intact phospho-AQP2 signals fit with the transcytosis trafficking model in Madin-Darby canine kidney cells. PS256 and pS269 signals were intracellularly detectable in wild-type AQP2 at the beginning of forskolin stimulation (1 min). These phospho-signals were detectable in basolateral membranes even after 10 min of stimulation. AQP2 stably inserted in the apical membrane increased pS269 and decreased pS261 signals. In an NDI-causing mutant P262L-AQP2, in which Ser-261 phospho-regulation is impaired, the pS256 and pS269 signals were detectable in the basolateral membranes with increased pS261 signals after forskolin stimulation. These results suggest that Ser-261 phospho-regulation is involved in pS256- and pS269-mediated AQP2 apical translocation. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Predicting fir trees stem diameters using Artificial Neural Network ...

    African Journals Online (AJOL)

    The system proposed in this paper can be applied in forest inventory making an accurate estimate of the volume of a sample tree based on only two diameter measurements (stump diameter, d0.3 and diameter at breast height, d1.3) and an estimate of the total tree height (h). Training of the ANNs was achieved through the ...

  1. Sonographic assessment of the portal vein diameter in apparently ...

    African Journals Online (AJOL)

    Conclusion: This study found the mean values of PV diameter in apparently healthy adults in our environment to be 9.60 ±. 1.41mm and that PV diameter ... Keywords: Portal vein diameter, sonography, Nigerian population, healthy adults. ... architecture that leads to enlargement of extrahepatic and intrahepatic portal ...

  2. Height-diameter equations for thirteen midwestern bottomland hardwood species

    Science.gov (United States)

    Kenneth C. Colbert; David R. Larsen; James R. Lootens

    2002-01-01

    Height-diameter equations are often used to predict the mean total tree height for trees when only diameter at breast height (dbh) is measured. Measuring dbh is much easier and is subject to less measurement error than total tree height. However, predicted heights only reflect the average height for trees of a particular diameter. In this study, we present a set of...

  3. Brain-Derived Neurotrophic Factor Loaded PS80 PBCA Nanocarrier for In Vitro Neural Differentiation of Mouse Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Chung, Chiu-Yen; Lin, Martin Hsiu-Chu; Lee, I-Neng; Lee, Tsong-Hai; Lee, Ming-Hsueh; Yang, Jen-Tsung

    2017-03-19

    Brain derived neurotrophic factor (BDNF) can induce neural differentiation in stem cells and has the potential for repair of the nervous system. In this study, a polysorbate 80-coated polybutylcyanoacrylate nanocarrier (PS80 PBCA NC) was constructed to deliver plasmid DNAs (pDNAs) containing BDNF gene attached to a hypoxia-responsive element (HRE-cmvBDNF). The hypoxia-sensing mechanism of BDNF expression and inductiveness of the nano-formulation on mouse induced pluripotent stem cells (iPSCs) to differentiate into neurons following hypoxia was tested in vitro with immunofluorescent staining and Western blotting. The HRE-cmvBDNF appeared to adsorb onto the surface of PS80 PBCA NC, with a resultant mean diameter of 92.6 ± 1.0 nm and zeta potential of -14.1 ± 1.1 mV. HIF-1α level in iPSCs was significantly higher in hypoxia, which resulted in a 51% greater BDNF expression when transfected with PS80 PBCA NC/HRE-cmvBDNF than those without hypoxia. TrkB and phospho-Akt were also elevated which correlated with neural differentiation. The findings suggest that PS80 PBCA NC too can be endocytosed to serve as an efficient vector for genes coupled to the HRE in hypoxia-sensitive cells, and activation of the PI3/Akt pathway in iPSCs by BDNF is capable of neural lineage specification.

  4. Brain-Derived Neurotrophic Factor Loaded PS80 PBCA Nanocarrier for In Vitro Neural Differentiation of Mouse Induced Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Chiu-Yen Chung

    2017-03-01

    Full Text Available Brain derived neurotrophic factor (BDNF can induce neural differentiation in stem cells and has the potential for repair of the nervous system. In this study, a polysorbate 80-coated polybutylcyanoacrylate nanocarrier (PS80 PBCA NC was constructed to deliver plasmid DNAs (pDNAs containing BDNF gene attached to a hypoxia-responsive element (HRE-cmvBDNF. The hypoxia-sensing mechanism of BDNF expression and inductiveness of the nano-formulation on mouse induced pluripotent stem cells (iPSCs to differentiate into neurons following hypoxia was tested in vitro with immunofluorescent staining and Western blotting. The HRE-cmvBDNF appeared to adsorb onto the surface of PS80 PBCA NC, with a resultant mean diameter of 92.6 ± 1.0 nm and zeta potential of −14.1 ± 1.1 mV. HIF-1α level in iPSCs was significantly higher in hypoxia, which resulted in a 51% greater BDNF expression when transfected with PS80 PBCA NC/HRE-cmvBDNF than those without hypoxia. TrkB and phospho-Akt were also elevated which correlated with neural differentiation. The findings suggest that PS80 PBCA NC too can be endocytosed to serve as an efficient vector for genes coupled to the HRE in hypoxia-sensitive cells, and activation of the PI3/Akt pathway in iPSCs by BDNF is capable of neural lineage specification.

  5. Backsplash studies for the Scintillator Pad Detector of LHCb in a tagged-photon test beam

    CERN Document Server

    Garrido, L; Miquel, R; Peralta, D

    2002-01-01

    The Scintillator Pad Detector (SPD) of the LHCb experiment is part of the calorimeter system, positioned just before the preshower (PS), and is meant to separate photons and electrons at level 0 of the trigger. A tagged-photon test beam allowed to test in photon signals the SPD. These signals are mainly due to pair production inside the scintillator and to particles generated in the electromagnetic shower in the PS and in the electromagnetic calorimeter (backsplash). The observed results in a test beam experiment stress the low inefficiencies in e/gamma separation arising from backsplash.

  6. Stable beams

    CERN Multimedia

    2015-01-01

    Stable beams: two simple words that carry so much meaning at CERN. When LHC page one switched from "squeeze" to "stable beams" at 10.40 a.m. on Wednesday, 3 June, it triggered scenes of jubilation in control rooms around the CERN sites, as the LHC experiments started to record physics data for the first time in 27 months. This is what CERN is here for, and it’s great to be back in business after such a long period of preparation for the next stage in the LHC adventure.   I’ve said it before, but I’ll say it again. This was a great achievement, and testimony to the hard and dedicated work of so many people in the global CERN community. I could start to list the teams that have contributed, but that would be a mistake. Instead, I’d simply like to say that an achievement as impressive as running the LHC – a machine of superlatives in every respect – takes the combined effort and enthusiasm of everyone ...

  7. Create and Publish a Hierarchical Progressive Survey (HiPS)

    Science.gov (United States)

    Fernique, P.; Boch, T.; Pineau, F.; Oberto, A.

    2014-05-01

    Since 2009, the CDS promotes a method for visualizing based on the HEALPix sky tessellation. This method, called “Hierarchical Progressive Survey" or HiPS, allows one to display a survey progressively. It is particularly suited for all-sky surveys or deep fields. This visualization method is now integrated in several applications, notably Aladin, the SiTools/MIZAR CNES framework, and the recent HTML5 “Aladin Lite". Also, more than one hundred surveys are already available in this view mode. In this article, we will present the progress concerning this method and its recent adaptation to the astronomical catalogs such as the GAIA simulation.

  8. Lo irreductible social y lo irreductible psíquico

    Directory of Open Access Journals (Sweden)

    Vincent Gaulejac, de

    2017-06-01

    Full Text Available Con base en la reconstrucción de las polaridades explicativas -lo irreductible social y lo irreductible psíquico-que atraviesan a las ciencias sociales, este texto propone trascender los modelos antagónicos y excluyentes. El objetivo es instaurar en el centro de la reflexión la idea de la dialktica existencial que restituye al sujeto tanto el contexto socio-histórico en el cual está localizado como el deseo y la singularidad que lo constituyen en productor de la afirmación de su individualidad y su historicidad.

  9. Viscometric characterization of PS/POSS hybrid nanocomposites

    OpenAIRE

    Bianchi, Otávio; Repenning, Gustavo B.; Mauler, Raquel S.; Oliveira, Ricardo V. B.; Canto, Leonardo B.

    2012-01-01

    Nanocompósitos híbridos de poliestireno (PS) e poliedros oligoméricos silsesquioxanos (POSS) com diferentes composições e graus de hibridização foram obtidos por processamento reativo no estado fundido utilizando-se peróxido de dicumila (DCP) como iniciador, na presença ou não de estireno como agente de transferência de radical. Os materiais foram caracterizados viscosimetricamente por cromatografia de permeação em gel (GPC) usando detecção tripla por espalhamento de luz, viscosimetria e índi...

  10. Laser beam welding by high-speed beam deflection; Laserstrahlschweissen durch High-Speed-Strahlbewegung

    Energy Technology Data Exchange (ETDEWEB)

    Klotzbach, A.; Morgenthal, L.; Beyer, E. [Fraunhofer-Institut fuer Werkstoff- und Strahltechnik, Dresden (Germany)

    1999-04-01

    The beam deflection system developed at Fraunhofer IWS can be used for rapid moving of a high power laser beam over the workpiece surface. Therefore it is possible to scan even rather small paths with high speed. The system contents two galvanometer scanner with specially designed lightweight mirrors in combination with a beam focusing unit. (Fig. 1). The high-speed welding of contours with small diameter is favorably done with both focusing optics and workpiece fixed (Fig. 2,3). Thus all notorius problems of conventional handling systems, as limited velocity and accuracy resulting from the inertia of the moved focusing head or workpiece, vanish. (orig.)

  11. Monte Carlo evaluation of magnetically focused proton beams for radiosurgery.

    Science.gov (United States)

    McAuley, Grant A; Heczko, Sarah; Nyguen, Theodore; Slater, James M; Slater, Jerry D; Wroe, Andrew J

    2018-01-25

    The purpose of this project is to investigate the advantages in dose distribution and delivery of proton beams focused by a triplet of quadrupole magnets in the context of potential radiosurgery treatments. Monte Carlo simulations were performed using various configurations of three quadrupole magnets located immediately upstream of a water phantom. Magnet parameters were selected to match what can be commercially manufactured as assemblies of rare-earth permanent magnetic materials. Focused unmodulated proton beams with a range of ~10 cm in water were target matched with passive collimated beams (the current beam delivery method for proton radiosurgery) and properties of transverse dose, depth dose and volumetric dose distributions were compared. Magnetically focused beams delivered beam spots of low eccentricity to Bragg peak depth with full widths at the 90% reference dose contour from ~ 2.5 to 5 mm. When focused initial beam diameters were larger than matching unfocused beams (10 of 11 cases) the focused beams showed 16% to 83% larger peak-to-entrance dose ratios and 1.3 to 3.4-fold increases in dose delivery efficiency. Peak-to-entrance and efficiency benefits tended to increase with larger magnet gradients and larger initial diameter focused beams. Finally, it was observed that focusing tended to shift dose in the water phantom volume from the 80%-20% dose range to below 20% of reference dose, compared to unfocused beams. We conclude that focusing proton beams immediately upstream from tissue entry using permanent magnet assemblies can produce beams with larger peak-to-entrance dose ratios and increased dose delivery efficiencies. Such beams could potentially be used in the clinic to irradiate small-field radiosurgical targets with fewer beams, lower entrance dose and shorter treatment times. © 2018 Institute of Physics and Engineering in Medicine.

  12. TRPV-1-mediated elimination of residual iPS cells in bioengineered cardiac cell sheet tissues

    Science.gov (United States)

    Matsuura, Katsuhisa; Seta, Hiroyoshi; Haraguchi, Yuji; Alsayegh, Khaled; Sekine, Hidekazu; Shimizu, Tatsuya; Hagiwara, Nobuhisa; Yamazaki, Kenji; Okano, Teruo

    2016-01-01

    The development of a suitable strategy for eliminating remaining undifferentiated cells is indispensable for the use of human-induced pluripotent stem (iPS) cell-derived cells in regenerative medicine. Here, we show for the first time that TRPV-1 activation through transient culture at 42 °C in combination with agonists is a simple and useful strategy to eliminate iPS cells from bioengineered cardiac cell sheet tissues. When human iPS cells were cultured at 42 °C, almost all cells disappeared by 48 hours through apoptosis. However, iPS cell-derived cardiomyocytes and fibroblasts maintained transcriptional and protein expression levels, and cardiac cell sheets were fabricated after reducing the temperature. TRPV-1 expression in iPS cells was upregulated at 42 °C, and iPS cell death at 42 °C was TRPV-1-dependent. Furthermore, TRPV-1 activation through thermal or agonist treatment eliminated iPS cells in cardiac tissues for a final concentration of 0.4% iPS cell contamination. These findings suggest that the difference in tolerance to TRPV-1 activation between iPS cells and iPS cell-derived cardiac cells could be exploited to eliminate remaining iPS cells in bioengineered cell sheet tissues, which will further reduce the risk of tumour formation. PMID:26888607

  13. TRPV-1-mediated elimination of residual iPS cells in bioengineered cardiac cell sheet tissues.

    Science.gov (United States)

    Matsuura, Katsuhisa; Seta, Hiroyoshi; Haraguchi, Yuji; Alsayegh, Khaled; Sekine, Hidekazu; Shimizu, Tatsuya; Hagiwara, Nobuhisa; Yamazaki, Kenji; Okano, Teruo

    2016-02-18

    The development of a suitable strategy for eliminating remaining undifferentiated cells is indispensable for the use of human-induced pluripotent stem (iPS) cell-derived cells in regenerative medicine. Here, we show for the first time that TRPV-1 activation through transient culture at 42 °C in combination with agonists is a simple and useful strategy to eliminate iPS cells from bioengineered cardiac cell sheet tissues. When human iPS cells were cultured at 42 °C, almost all cells disappeared by 48 hours through apoptosis. However, iPS cell-derived cardiomyocytes and fibroblasts maintained transcriptional and protein expression levels, and cardiac cell sheets were fabricated after reducing the temperature. TRPV-1 expression in iPS cells was upregulated at 42 °C, and iPS cell death at 42 °C was TRPV-1-dependent. Furthermore, TRPV-1 activation through thermal or agonist treatment eliminated iPS cells in cardiac tissues for a final concentration of 0.4% iPS cell contamination. These findings suggest that the difference in tolerance to TRPV-1 activation between iPS cells and iPS cell-derived cardiac cells could be exploited to eliminate remaining iPS cells in bioengineered cell sheet tissues, which will further reduce the risk of tumour formation.

  14. [Induced pluripotent stem (iPS) cell - issues for clinical application - ].

    Science.gov (United States)

    Aoi, Takashi

    2013-01-01

    Induced pluripotent stem (iPS) cells are generated from somatic cells by introducing small sets of transcription factors. iPS cells demonstrate pluripotency and the ability to self-renew. In addition, iPS cells can be generated from donor individuals with particular characteristics. Based on these features, iPS cells are expected to be applicable in drug discovery, the study of disease mechanisms and cell therapy. From a technical point of view, "diversity" is the key word. At present, iPS cells can be derived using various techniques, resulting in diversity in the quality of iPS cells generated. Therefore, optimization of the derivation technology is one of the most important issues. Another "diversity" is in the propensities amongst iPS cell lines derived using similar techniques. Thus, strategies for selecting good quality lines remain to be established. Considering such technical hurdles, establishment of an iPS cell bank consisting of high quality and versatile iPS lines is a promising idea because of the merits of cost and quality control. Now, we are exploring relevant parameters for the quality control of banked cells. The challenges facing clinical application of iPS cells are new but not unprecedented. To realize clinical applications of iPS cells, we need to make these challenges clear and overcome them through partnership not only with industry, governments and universities, but also patients and society at large.

  15. Methods for iPS cell generation for basic research and clinical applications.

    Science.gov (United States)

    Mochiduki, Yuji; Okita, Keisuke

    2012-06-01

    The induction of pluripotency can be achieved by forced expression of defined factors in somatic cells. The established cells, termed induced pluripotent stem (iPS) cells, have pluripotency and an infinite capacity for self-renewal in common with embryonic stem (ES) cells. Patient-specific iPS cells could be a useful source for drug discovery and cell transplantation therapies; however, the original method for iPS cell generation had several issues that were obstacles to their clinical application. Recent studies have brought about various improvements for iPS cell generation and uncovered several characteristics of iPS cells. Here we summarize the current status of iPS cell studies, with a focus on the improved methods that can be used to generate iPS cells, and also refer to the future challenges. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Beam forming system modernization at the MMF linac proton injector

    CERN Document Server

    Derbilov, V I; Nikulin, E S; Frolov, O T

    2001-01-01

    The isolation improvements of the beam forming system (BFS) of the MMF linac proton injector ion source are reported. The mean beam current and,accordingly, BFS electrode heating were increased when the MMF linac has began to operate regularly in long beam sessions with 50 Hz pulse repetition rate. That is why the BFS electrode high-voltage isolation that was made previously as two consequently and rigidly glued solid cylinder insulators has lost mechanical and electric durability. The substitution of large (160 mm) diameter cylinder insulator for four small diameter (20 mm) tubular rods has improved vacuum conditions in the space of beam forming and has allowed to operate without failures when beam currents being up to 250 mA and extraction and focusing voltage being up to 25 and 40 kV respectively. Moreover,the construction provides the opportunity of electrode axial move. The insulators are free from electrode thermal expansion mechanical efforts in a transverse direction.

  17. Synthesis and Characterization of Core-shell ZrO2/PAAEM/PS Nanoparticles

    Directory of Open Access Journals (Sweden)

    Jiang XC

    2008-01-01

    Full Text Available Abstract This work demonstrates the synthesis of core-shell ZrO2/PAAEM/PS nanoparticles through a combination of sol–gel method and emulsifier-free emulsion polymerizaiton. By this method, the modified nanometer ZrO2cores were prepared by chemical modification at a molecular level of zirconium propoxide with monomer of acetoacetoxyethylmethacrylate (AAEM, and then copolymerized with vinyl monomer to form uniform-size hybrid nanoparticles with diameter of around 250 nm. The morphology, composition, and thermal stability of the core-shell particles were characterized by various techniques including transmission electron microscopy (TEM, X-ray diffractometer (XRD, Fourier transform infrared spectroscopy (FTIR, X-ray photoelectron spectroscopy (XPS, and thermal-gravimetry analyzer (TGA. The results indicate that the inorganic–organic nanocomposites exhibit good thermal stability with the maximum decomposition temperature of ~447 °C. This approach would be useful for the synthesis of other inorganic–organic nanocomposites with desired functionalities.

  18. High field superconducting beam transport in a BNL primary proton beam

    Energy Technology Data Exchange (ETDEWEB)

    Allinger, J.; Brown, H.N.; Carroll, A.S.; Danby, G.; DeVito, B.; Glenn, J.W.; Jackson, J.; Keith, W.; Lowenstein, D.; Prodell, A.G.

    1979-01-01

    Construction of a slow external beam switchyard at the BNL AGS requires a rapid 20.4/sup 0/ bend in the upstream end of the beam line. Two curved superconducting window dipole magnets, operating at 6.0 T and about 80% of short sample magnetic field, will be utilized with two small superconducting sextupoles to provide the necessary deflection for a 28.5 GeV/c primary proton beam. Because the magnets will operate in a primary proton beam environment, they are designed to absorb large amounts of radiation heating from the beam without quenching. The field quality of the superconducting magnets is extremely good. Computer field calculations indicate a field error, ..delta..B/B/sub 0/, equivalent to approx. = 1 x 10/sup -4/ up to 75% of the 8.26 cm full aperture diameter in the magnet.

  19. Properties of Extruded PS-212 Type Self-Lubricating Materials

    Science.gov (United States)

    Waters, W. J.; Sliney, H. E.; Soltis, R. F.

    1993-01-01

    Research has been underway at the NASA Lewis Research Center since the 1960's to develop high temperature, self-lubricating materials. The bulk of the research has been done in-house by a team of researchers from the Materials Division. A series of self-lubricating solid material systems has been developed over the years. One of the most promising is the composite material system referred to as PS-212 or PM-212. This material is a powder metallurgy product composed of metal bonded chromium carbide and two solid lubricating materials known to be self-lubricating over a wide temperature range. NASA feels this material has a wide potential in industrial applications. Simplified processing of this material would enhance its commercial potential. Processing changes have the potential to reduce processing costs, but tribological and physical properties must not be adversely affected. Extrusion processing has been employed in this investigation as a consolidation process for PM-212/PS-212. It has been successful in that high density bars of EX-212 (extruded PM-212) can readily be fabricated. Friction and strength data indicate these properties have been maintained or improved over the P.M. version. A range of extrusion temperatures have been investigated and tensile, friction, wear, and microstructural data have been obtained. Results indicate extrusion temperatures are not critical from a densification standpoint, but other properties are temperature dependent.

  20. KSR-based medium improves the generation of high-quality mouse iPS cells.

    Science.gov (United States)

    Liu, Kai; Wang, Fang; Ye, Xiaoying; Wang, Lingling; Yang, Jiao; Zhang, Jingzhuo; Liu, Lin

    2014-01-01

    Induced pluripotent stem (iPS) cells from somatic cells have great potential for regenerative medicine. The efficiency in generation of iPS cells has been significantly improved in recent years. However, the generation of high-quality iPS cells remains of high interest. Consistently, we demonstrate that knockout serum replacement (KSR)-based medium accelerates iPS cell induction and improves the quality of iPS cells, as confirmed by generation of chimeras and all iPS cell-derived offspring with germline transmission competency. Both alkaline phosphatase (AP) activity assay and expression of Nanog have been used to evaluate the efficiency of iPS cell induction and formation of ES/iPS cell colonies; however, appropriate expression of Nanog frequently indicates the quality of ES/iPS cells. Interestingly, whereas foetal bovine serum (FBS)-based media increase iPS cell colony formation, as revealed by AP activity, KSR-based media increase the frequency of iPS cell colony formation with Nanog expression. Furthermore, inhibition of MAPK/ERK by a specific inhibitor, PD0325901, in KSR- but not in FBS-based media significantly increases Nanog-GFP+ iPS cells. In contrast, addition of bFGF in KSR-based media decreases proportion of Nanog-GFP+ iPS cells. Remarkably, PD can rescue Nanog-GFP+ deficiency caused by bFGF. These data suggest that MAPK/ERK pathway influences high quality mouse iPS cells and that KSR- and PD-based media could enrich homogeneous authentic pluripotent stem cells.

  1. Dosimetric characteristics of the small diameter BrainLab™ cones used for stereotactic radiosurgery.

    Science.gov (United States)

    Khelashvili, Gocha; Chu, James; Diaz, Aidnag; Turian, Julius

    2012-01-05

    The purpose was to study the dosimetric characteristics of the small diameter (≤ 10.0 mm) BrainLAB cones used for stereotactic radiosurgery (SRS) treatments in conjunction with a Varian Trilogy accelerator. Required accuracy and precision in dose delivery during SRS can be achieved only when the geometric and dosimetric characteristics of the small radiation fields is completely understood. Although a number of investigators have published the dosimetric characteristics of SRS cones, to our knowledge, there is no generally accepted value for the relative output factor (ROF) for the 5.0 mm diameter cone. Therefore, we have investigated the dosimetric properties of the small (≤ 10.0 mm) diameter BrainLAB SRS cones used in conjunction with the iPlan TPS and a Trilogy linear accelerator with a SRS beam mode. Percentage depth dose (PDD), off-axis ratios (OAR), and ROF were measured using a SRS diode and verified with Monte Carlo (MC) simulations. The dependence of ROF on detector material response was studied. The dependence of PDD, OAR, and ROF on the alignment of the beam CAX with the detector motion line was also investigated using MC simulations. An agreement of 1% and 1 mm was observed between measurements and MC for PDD and OAR. The calculated ROF for the 5.0 mm diameter cone was 0.692 ± 0.008--in good agreement with the measured value of 0.683 ± 0.007 after the diode response was corrected. Simulations of the misalignment between the beam axis and detector motion axis for angles between 0.5°-1.0° have shown a deviation > 2% in PDD beyond a certain depth. We have also provided a full set of dosimetric data for BrainLAB SRS cones. Monte Carlo calculated ROF values for cones with diameters less than 10.0 mm agrees with measured values to within 1.8%. Care should be exercised when measuring PDD and OAR for small cones. We recommend the use of MC to confirm the measurement under these conditions.

  2. A new search for anomalous neutrino oscillations at the CERN-PS

    CERN Document Server

    Baibussinov, B.; Centro, S.; Gibin, D.; Guglielmi, A.; Pietropaolo, F.; Rubbia, C.; Sala, P.

    2009-01-01

    The LSND experiment has observed a 3.8 sigma excess of anti-nu_e events from an anti-nu_mu beam coming from pions at rest. If confirmed, the LSND anomaly would imply new physics beyond the standard model, presumably in the form of some additional sterile neutrinos. The MiniBooNE experiment at FNAL-Booster has further searched for the LSND anomaly. Above 475 MeV, the nu_e result is excluding the LSND anomaly to about 1.6 sigma but it introduces an unexplained, new 3.0 sigma anomaly at lower energies, down to 200 MeV. The nu_e data have so far an insufficient statistics to be conclusive with LSND's anti-nu_e. The present proposal at the CERN-PS is based on two strictly identical LAr-TPC detectors in the near and far positions, respectively at 127 and 850 m from the neutrino (or antineutrino) target and focussing horn, observing the electron-neutrino signal. This project will benefit from the already developed technology of ICARUS T600, well tested on surface in Pavia, without the need of any major R&D activ...

  3. MicroRNA expression profiles of human iPS cells, retinal pigment epithelium derived from iPS, and fetal retinal pigment epithelium.

    Science.gov (United States)

    Greene, Whitney A; Muñiz, Alberto; Plamper, Mark L; Kaini, Ramesh R; Wang, Heuy-Ching

    2014-06-24

    The objective of this report is to describe the protocols for comparing the microRNA (miRNA) profiles of human induced-pluripotent stem (iPS) cells, retinal pigment epithelium (RPE) derived from human iPS cells (iPS-RPE), and fetal RPE. The protocols include collection of RNA for analysis by microarray, and the analysis of microarray data to identify miRNAs that are differentially expressed among three cell types. The methods for culture of iPS cells and fetal RPE are explained. The protocol used for differentiation of RPE from human iPS is also described. The RNA extraction technique we describe was selected to allow maximal recovery of very small RNA for use in a miRNA microarray. Finally, cellular pathway and network analysis of microarray data is explained. These techniques will facilitate the comparison of the miRNA profiles of three different cell types.

  4. Forward production of charged pions with incident $\\pi^{\\pm}$ on nuclear targets measured at the CERN PS

    CERN Document Server

    Apollonio, M.; Bagulya, A.; Barr, G.; Blondel, A.; Bobisut, F.; Bogomilov, M.; Bonesini, M.; Booth, C.; Borghi, S.; Bunyatov, S.; Burguet-Castell, J.; Catanesi, M.G.; Cervera-Villanueva, A.; Chimenti, P.; Coney, L.; Di Capua, E.; Dore, U.; Dumarchez, J.; Edgecock, R.; Ellis, M.; Ferri, F.; Gastaldi, U.; Giani, S.; Giannini, G.; Gibin, D.; Gilardoni, S.; Gorbunov, P.; Gossling, C.; Gomez-Cadenas, J.J.; Grant, A.; Graulich, J.S.; Gregoire, G.; Grichine, V.; Grossheim, A.; Guglielmi, A.; Howlett, L.; Ivanchenko, A.; Ivanchenko, V.; Kayis-Topaksu, A.; Kirsanov, M.; Kolev, D.; Krasnoperov, A.; Martin-Albo, J.; Meurer, C.; Mezzetto, M.; Mills, G.B.; Morone, M.C.; Novella, P.; Orestano, D.; Palladino, V.; Panman, J.; Papadopoulos, I.; Pastore, F.; Piperov, Stefan; Polukhina, N.; Popov, B.; Prior, G.; Radicioni, E.; Schmitz, D.; Schroeter, R.; Skoro, G; Sorel, M.; Tcherniaev, E.; Temnikov, P.; Tereschenko, V.; Tonazzo, A.; Tortora, L.; Tsenov, R.; Tsukerman, I.; Vidal-Sitjes, G.; Wiebusch, C.; Zucchelli, P.

    2009-01-01

    Measurements of the double-differential $\\pi^{\\pm}$ production cross-section in the range of momentum 0.5 GeV/c < p < 8.0 GeV/c and angle 0.025 rad < theta < 0.25 rad in interactions of charged pions on beryllium, carbon, aluminium, copper, tin, tantalum and lead are presented. These data represent the first experimental campaign to systematically measure forward pion hadroproduction. The data were taken with the large acceptance HARP detector in the T9 beam line of Incident particles, impinging on a 5% nuclear interaction length target, were identified by an elaborate system of beam detectors. The tracking and identification of the produced particles was performed using the forward spectrometer of the HARP detector. Results are obtained for the double-differential cross-sections mainly at four incident pion beam momenta (3 GeV/c, 5 GeV/c, 8 GeV/c and 12 GeV/c). The measurements are compared with the GEANT4 and MARS Monte Carlo simulation. the CERN PS.

  5. Simulation and optimization of beam losses during continuous transfer extraction at the CERN Proton Synchrotron

    CERN Document Server

    Garcia, J B

    2011-01-01

    The proton beams used for the fixed target physics at the Super Proton Synchrotron (SPS) are extracted from the Proton Synchrotron ( PS) by a multiturn technique called continuous transfer (CT). During the CT extraction, large losses are observed in locations where the machine aperture should be large enough to accommodate the circulating beam. This limits the maximum intensity deliverable due to the induced stray radiation outside the PS tunnel. Scattered particles from the interaction with the electrostatic septum are identified as the possible source of these losses. This article presents a detailed study aiming to understand the origin of losses and propose possible cures. The simulations could reproduce accurately the beam loss pattern measured in real machine operation and determine the beam shaving, intrinsic to the extraction process, as the cause for the unexpected losses. Since these losses are unavoidable, the proposed solution implies a new optics scheme displacing the losses to a region with bett...

  6. Comparison of implosion core metrics: A 10 ps dilation X-ray imager vs a 100 ps gated microchannel plate

    Science.gov (United States)

    Nagel, S. R.; Benedetti, L. R.; Bradley, D. K.; Hilsabeck, T. J.; Izumi, N.; Khan, S.; Kyrala, G. A.; Ma, T.; Pak, A.

    2016-11-01

    The dilation x-ray imager (DIXI) [T. J. Hilsabeck et al., Rev. Sci. Instrum. 81, 10E317 (2010); S. R. Nagel et al., ibid. 83, 10E116 (2012); S. R. Nagel et al., ibid. 85, 11E504 (2014)] is a high-speed x-ray framing camera that uses the pulse-dilation technique to achieve a temporal resolution of less than 10 ps. This is a 10 × improvement over conventional framing cameras currently employed on the National Ignition Facility (NIF) (100 ps resolution), and otherwise only achievable with 1D streaked imaging. A side effect of the dramatically reduced gate width is the comparatively lower detected signal level. Therefore we implement a Poisson noise reduction with non-local principal component analysis method [J. Salmon et al., J. Math. Imaging Vision 48, 279294 (2014)] to improve the robustness of the DIXI data analysis. Here we present results on ignition-relevant experiments at the NIF using DIXI. In particular we focus on establishing that/when DIXI gives reliable shape metrics (P0, P2, and P4 Legendre modes, and their temporal evolution/swings).

  7. Generation of subnanosecond electron beams in air at atmospheric pressure

    Science.gov (United States)

    Kostyrya, I. D.; Tarasenko, V. F.; Baksht, E. Kh.; Burachenko, A. G.; Lomaev, M. I.; Rybka, D. V.

    2009-11-01

    Optimum conditions for the generation of runaway electron beams with maximum current amplitudes and densities in nanosecond pulsed discharges in air at atmospheric pressure are determined. A supershort avalanche electron beam (SAEB) with a current amplitude of ˜30 A, a current density of ˜20 A/cm2, and a pulse full width at half maximum (FWHM) of ˜100 ps has been observed behind the output foil of an air-filled diode. It is shown that the position of the SAEB current maximum relative to the voltage pulse front exhibits a time shift that varies when the small-size collector is moved over the foil surface.

  8. Hydrogen sulfide down-regulates BACE1 and PS1 via activating PI3K/Akt pathway in the brain of APP/PS1 transgenic mouse.

    Science.gov (United States)

    He, Xuan-Li; Yan, Ning; Chen, Xiao-Shan; Qi, Yun-Wen; Yan, Yong; Cai, Zhiyou

    2016-10-01

    Endogenous hydrogen sulfide (H2S) may have multiple physiological functions in brain. Our previous study showed that H2S improved spatial memory impairment and decreased the production of Aβ in APP/PS1 transgenic mice. However, many of the underlying mechanisms are not still being elucidated. The aim of the present study is to investigate the neuroprotective mechanisms of H2S involving in the activity of β-secretase (BACE1), γ-secretase (PS1) and α-secretase (ADAM17). Morris water maze was used to measure the behavior change. The levels of Aβ40 and Aβ42 were quantified using colorimetric ELISA kits and immunohistochemical analysis. The levels of BACE1, PS1, ADAM17, pAkt, pp38MAPK, pERK and pJNK were tested by Western blot analysis in normal mice, APP/PS1 transgenic mice and 50μmol/kg-NaHS-treated transgenic mice. On the basis of exogenous H2S treatment, LY294002 (inhibitors of PI3K/Akt) or PD98059 (inhibitors of MAPK/ERK) was injected into lateral cerebral ventricle. The levels of BACE1, PS1 and pp38MAPK were increased and ADAM17 were decreased in the APP/PS1 transgenic mice. After intraperitoneal administration of an H2S donor (NaHS) into APP/PS1 mice, the levels of BACE1, PS1 and pp38MAPK were reduced and ADAM17 increased. The level of pp38 MAPKs, pAkt and pERK1/2 was increased in APP/PS1 transgenic mice compared with normal mice (ptransgenic mice and normal mice (p>0.05). These results demonstrated that LY294002 inhibited the effect of H2S on decreasing the BACE1 and PS1, reducing the level of Aβ and improving memory impairment in APP/PS1 transgenic mice. PD98059 had no influence on the expression of BACE1 and PS1. H2S inhibits the expression of BACE1 and PS1 by activating PI3K/Akt pathway in AD. Copyright © 2016 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  9. Parametric Probability Distribution Functions for Axon Diameters of Corpus Callosum

    OpenAIRE

    Sepehrband, Farshid; Alexander, Daniel C; Clark, Kristi A.; Kurniawan, Nyoman D; Yang, Zhengyi; Reutens, David C.

    2016-01-01

    Axon diameter is an important neuroanatomical characteristic of the nervous system that alters in the course of neurological disorders such as multiple sclerosis. Axon diameters vary, even within a fiber bundle, and are not normally distributed. An accurate distribution function is therefore beneficial, either to describe axon diameters that are obtained from a direct measurement technique (e.g., microscopy), or to infer them indirectly (e.g., using diffusion-weighted MRI). The gamma distribu...

  10. Propagation-invariant beams with quantum pendulum spectra: from Bessel beams to Gaussian beam-beams.

    Science.gov (United States)

    Dennis, Mark R; Ring, James D

    2013-09-01

    We describe a new class of propagation-invariant light beams with Fourier transform given by an eigenfunction of the quantum mechanical pendulum. These beams, whose spectra (restricted to a circle) are doubly periodic Mathieu functions in azimuth, depend on a field strength parameter. When the parameter is zero, pendulum beams are Bessel beams, and as the parameter approaches infinity, they resemble transversely propagating one-dimensional Gaussian wave packets (Gaussian beam-beams). Pendulum beams are the eigenfunctions of an operator that interpolates between the squared angular momentum operator and the linear momentum operator. The analysis reveals connections with Mathieu beams, and insight into the paraxial approximation.

  11. Numerical simulation of crystalline ion beams in storage ring

    CERN Document Server

    Meshkov, I N; Katayama, T; Sidorin, A; Smirnov, A Yu; Syresin, E M; Trubnikov, G; Tsutsui, H

    2004-01-01

    The use of crystalline ion beams can increase luminosity in the collider and in experiments with targets for investigation of rare radioactive isotopes. The ordered state of circulating ion beams was observed at several storage rings: NAP-M (Proceedings of the Fourth All Union Conference on Charged Particle Accelerators, Vol. 2, Nauka, Moscow, 1975 (in Russian); Part. Accel. 7 (1976) 197; At. Energy 40 (1976) 49; Preprint CERN/PS/AA 79-41, Geneva, 1979) (Novosibirsk), ESR (Phys. Rev. Lett. 77 (1996) 3803) and SIS (Proceedings of EPAC'2000, 2000) (Darmstadt), CRYRING (Proceedings of PAC'2001, 2001) (Stockholm) and PALLAS (Proceedings of the Conference on Applications of Accelerators in Research and Industry, AIP Conference Proceedings, p. 576, in preparation) (Munchen). New criteria of the beam orderliness are derived and verified with a new program code. Molecular dynamics technique is inserted in BETACOOL program (Proceedings of Beam Cooling and Related Topics, Bad Honnef, Germany, 2001) and used for numeric...

  12. Atom-bond connectivity index and diameter of graphs

    Directory of Open Access Journals (Sweden)

    Lin WU

    2016-12-01

    Full Text Available For further study of the numerous nice properties of topological indices in physical and chemical fields, it is worth considering the relation between a degree-based index and a distance-based index. With the fact that diameter is an invariant based on distance, the relations between atom-bond connectivity index, diameter in trees and unicyclic graphs are studied. Based on relative lemma, the relation between atom-bond connectivity index and diameter in tree and unicyclic graphs is investigated, then the sharp lower bounds of the difference of index and diameter are given.

  13. Beam Characterization at the Neutron Radiography Facility

    Energy Technology Data Exchange (ETDEWEB)

    Sarah Morgan; Jeffrey King

    2013-01-01

    The quality of a neutron imaging beam directly impacts the quality of radiographic images produced using that beam. Fully characterizing a neutron beam, including determination of the beam’s effective length-to-diameter ratio, neutron flux profile, energy spectrum, image quality, and beam divergence, is vital for producing quality radiographic images. This project characterized the east neutron imaging beamline at the Idaho National Laboratory Neutron Radiography Reactor (NRAD). The experiments which measured the beam’s effective length-to-diameter ratio and image quality are based on American Society for Testing and Materials (ASTM) standards. An analysis of the image produced by a calibrated phantom measured the beam divergence. The energy spectrum measurements consist of a series of foil irradiations using a selection of activation foils, compared to the results produced by a Monte Carlo n-Particle (MCNP) model of the beamline. Improvement of the existing NRAD MCNP beamline model includes validation of the model’s energy spectrum and the development of enhanced image simulation methods. The image simulation methods predict the radiographic image of an object based on the foil reaction rate data obtained by placing a model of the object in front of the image plane in an MCNP beamline model.

  14. Beam-loss-induced electrical stress test on CMS Silicon Strip Modules

    CERN Document Server

    Fahrer, M; Hartmann, F; Heier, S; MacPherson, A; Muller, T H; Weiler, T h

    2004-01-01

    Based on simulated LHC beam loss scenarios, fully depleted CMS silicon tracker modules and sensors were exposed to 42 ns-long beam spills of approximately 10**1**1 protons per spill at the PS at CERN. The ionisation dose was sufficient to short circuit the silicon sensors. The dynamic behaviour of bias voltage, leakage currents and voltages over coupling capacitors were monitored during the impact. Results of pre- and post-qualification as well as the dynamic behaviour are shown.

  15. Thermal stability of gold-PS nanocomposites thin films

    Indian Academy of Sciences (India)

    The composite thin films were prepared by wet chemical approach and the samples were then subsequently spin-coated on a carbon-coated copper grid for TEM measurements. TEM measurements were performed at liquid nitrogen temperatures to reduce the electron–beam-induced radiation damage. The results showed ...

  16. Innards of a New Injection Septum for the PS Booster

    CERN Multimedia

    CERN PhotoLab

    1974-01-01

    The original injection septum was replaced by this new one, of improved design. It is really 4 septum magnets, for the 4 levels of the Booster rings, mounted on a common structure and housed in a single tank. The 50 MeV proton beam from the linac enters the visible septum aperture and moves from right to left.

  17. Development and characterization of sub-100 ps photomultiplier tubes.

    Science.gov (United States)

    Horsfield, C J; Rubery, M S; Mack, J M; Young, C S; Herrmann, H W; Caldwell, S E; Evans, S C; Sedilleo, T J; Kim, Y H; McEvoy, A; Milnes, J S; Howorth, J; Davis, B; O'Gara, P M; Garza, I; Miller, E K; Stoeffl, W; Ali, Z

    2010-10-01

    We describe the evaluation of a microchannel plate (MCP) photomultiplier tube (PMT), incorporating a 3 μm pore MCP and constant voltage anode and cathode gaps. The use of the small pore size results in PMTs with response functions of the order of 85 ps full-width-half-maximum, while the constant electric field across the anode and cathode gaps produces a uniform response function over the entire operating range of the device. The PMT was characterized on a number of facilities and employed on gas Cherenkov detectors fielded on various deuterium tritium fuel (DT) implosions on the Omega Laser Facility at the University of Rochester. The Cherenkov detectors are part of diagnostic development to measure Gamma ray reaction history for DT implosions on the National Ignition Facility.

  18. MD on Head-Tail Instability in the PS Booster

    CERN Document Server

    Kornilov, V; Mikulec, B; Aumon, S; Rumolo, G

    2013-01-01

    Machine study experiments on the coherent instabilities appearing along the magnetic ramp have been performed at the CERN PS Booster synchrotron in the week of June 11-15, 2012. The space- and time structure of the head-tail instabilities was recorded by the triggered pick-up signals due to reproducibility of the occurrence time in the shot-by-shot sense. The intensity thresholds, the absolute growth rates and the mode structure have been compared for the bunches in the single-rf and in three types of the double-rf operation. The growth rates are compared to the instantaneous synchrotron frequencies, in the cases of the large corresponding ratio the head-tail mode structure is deformed by the driving impedance. Bunch parameters measurements indicate that the PSB bunches are in the regime of very strong transverse space-charge all along the magnetic ramp.

  19. Migrating the CERN PS control system to IBM workstations

    CERN Document Server

    De Metz-Noblat, N

    1995-01-01

    The workstations used within the control system of the CERN PS accelerator complex are not produced any more. We had therefore to review the software primary used as user interface and we achieved a port to IBM workstations. We are also preparing the maintenance of this code for the next ten years with minimal staff. This implies a clear separation between general computing facilities, control system developments, and operation. In order to share our experience, we will try to summarize various aspects of this migration: - system installation principles used to speed-up error recovery time and long-term maintenance costs, - problems correlated with the coexistence of two different platforms during migration, - software problems due to the platform and operating system changes, - hidden dependencies from a specific manufacturer.

  20. First PS magnet unit, with members of the Magnet Group.

    CERN Multimedia

    CERN PhotoLab

    1956-01-01

    Members of the Magnet Group, sitting atop the first unit of the PS combined-function magnet. The picture was taken at the Institute of Physics of Geneva University, as CERN was still a muddy construction site at that time. All these people have now retired, but all of the magnets are still pulsing away. Front row (left to right): R.Tinguely, C.Germain, G.Plass, D.Neet, B.de Raad, M.Cavallaro, K.H.Reich, G.Kuhn, J.Nilsson, C.A.Ramm, Paillard. Second row: L.Resegotti, M.Niklaus, C.J.Zilverschoon, R.Bertolotto, Marcellin, G.Brianti, P.Collet. Standing behind: B.Kuiper.

  1. Surface morphology of PS-PDMS diblock copolymer films

    DEFF Research Database (Denmark)

    Andersen, T.H.; Tougaard, S.; Larsen, N.B.

    2001-01-01

    Spin coated thin films (∼400 Å) of poly(styrene)–poly(dimethylsiloxane) (PS–PDMS) diblock copolymers have been investigated using X-ray Photoelectron Spectroscopy and Atomic Force Microscopy. Surface segregation of the poly(dimethylsiloxane) blocks was studied for five diblock copolymers which...... by use of peak shape analysis of the X-ray Photoelectron Spectra via the Tougaard Method. The amount of dimethylsiloxane in the uppermost part of the films was quantified as a function of annealing time and temperature. For annealing above the PS glass transition temperature, surface segregation...... of the dimethylsiloxane chain-ends occurs for all the studied PS–PDMS diblock copolymers. At room temperature, surface segregation takes place only when the amount of dimethylsiloxane in the diblock copolymers is small....

  2. Sub-10ps monolithic and low-power photodetector readout

    Energy Technology Data Exchange (ETDEWEB)

    Varner, Gary S.; Ruckman, Larry L.

    2009-02-20

    Recent advances in photon detectors have resulted in high-density imaging arrays that offer many performance and cost advantages. In particular, the excellent transit time spread of certain devices show promise to provide tangible benefits in applications such as Positron Emission Tomography (PET). Meanwhile, high-density, high-performance readout techniques have not kept on pace for exploiting these developments. Photodetector readout for next generation high event rate particle identification and time-resolved PET requires a highly-integrated, low-power, and cost-effective readout technique. We propose fast waveform sampling as a method that meets these criteria and demonstrate that sub-10ps resolution can be obtained for an existing device.

  3. Small-size meshless 50 ps streak tube

    Science.gov (United States)

    Ageeva, N. V.; Andreev, S. V.; Belolipetski, V. S.; Bryukhnevich, G. I.; Greenfield, D. E.; Ivanova, S. R.; Kaverin, A. M.; Khohlova, A. N.; Kuz'menko, E. A.; Levina, G. P.; Makushina, V. A.; Monastyrskiy, M. A.; Schelev, M. Ya.; Semichastnova, Z. M.; Serdyuchenko, Yu. N.; Skaballanovich, T. A.; Sokolov, V. E.

    2008-11-01

    In contrast to the conventional image intensifier with large work area, a streak image tube should possess additional important feature - the comparatively small temporal distortion at the entire work area of the photocathode. With this additional engineering restriction taken into account, a novel small-size meshless streak image tube has been developed by means of numerical optimization. The tube with 25-mm wide work area contains a pair of deflection plates to sweep the electron image along the 25 mm output phosphor screen that is separated by 100 mm from the photocathode. The electron image can be shuttered with a 300 V blanking electric pulse. Electron-optical magnification of the tube is unit; spatial resolution reaches 30 lp/mm over the entire photocathode work area; temporal resolution lies in the 20 - 50 ps range, depending on the accelerating voltage (6 - 15 kV).

  4. Psödohipoparatiroidi Tip 1A: Olgu Sunumu

    Directory of Open Access Journals (Sweden)

    Mehmet Güven

    2017-06-01

    Full Text Available Psödohipoparatiroidizm (PHPT; hedef organın parathormona (PTH yanıt vermediği kalıtımsal bir bozukluktur. Biyokimyasal olarak; hipokalsemi, hiperfosfatemi ve PTH yüksekliği ile karakterizedir. PTH uygulamasına verilen yanıt belirgin derecede düşüktür. Tip 1A, biyokimyasal özelliklere ek olarak Albright herediter osteodistrofisi (AHO olarak bilinen karakteristik somatik bir fenotipe de sahiptir. Bu fenotipin, kısa boy, yuvarlak yüz, frontal bombelik, brakidaktili, obezite özelikleri bulunmaktadır. Burada biz, hipokalsemi ve Albright herediter osteodistrofisi tanısı koyduğumuz; kalsiyum, aktif D vitamini ile tedavi ettiğimiz olgumuzu sunduk.

  5. Updating the Psoriatic Arthritis (PsA) Core Domain Set: A Report from the PsA Workshop at OMERACT 2016.

    Science.gov (United States)

    Orbai, Ana-Maria; de Wit, Maarten; Mease, Philip J; Callis Duffin, Kristina; Elmamoun, Musaab; Tillett, William; Campbell, Willemina; FitzGerald, Oliver; Gladman, Dafna D; Goel, Niti; Gossec, Laure; Hoejgaard, Pil; Leung, Ying Ying; Lindsay, Chris; Strand, Vibeke; van der Heijde, Désirée M; Shea, Bev; Christensen, Robin; Coates, Laura; Eder, Lihi; McHugh, Neil; Kalyoncu, Umut; Steinkoenig, Ingrid; Ogdie, Alexis

    2017-10-01

    To include the patient perspective in accordance with the Outcome Measures in Rheumatology (OMERACT) Filter 2.0 in the updated Psoriatic Arthritis (PsA) Core Domain Set for randomized controlled trials (RCT) and longitudinal observational studies (LOS). At OMERACT 2016, research conducted to update the PsA Core Domain Set was presented and discussed in breakout groups. The updated PsA Core Domain Set was voted on and endorsed by OMERACT participants. We conducted a systematic literature review of domains measured in PsA RCT and LOS, and identified 24 domains. We conducted 24 focus groups with 130 patients from 7 countries representing 5 continents to identify patient domains. We achieved consensus through 2 rounds of separate surveys with 50 patients and 75 physicians, and a nominal group technique meeting with 12 patients and 12 physicians. We conducted a workshop and breakout groups at OMERACT 2016 in which findings were presented and discussed. The updated PsA Core Domain Set endorsed with 90% agreement by OMERACT 2016 participants included musculoskeletal disease activity, skin disease activity, fatigue, pain, patient's global assessment, physical function, health-related quality of life, and systemic inflammation, which were recommended for all RCT and LOS. These were important, but not required in all RCT and LOS: economic cost, emotional well-being, participation, and structural damage. Independence, sleep, stiffness, and treatment burden were on the research agenda. The updated PsA Core Domain Set was endorsed at OMERACT 2016. Next steps for the PsA working group include evaluation of PsA outcome measures and development of a PsA Core Outcome Measurement Set.

  6. Test beam studies of the light yield, time and coordinate resolutions of scintillator strips with WLS fibers and SiPM readout

    Energy Technology Data Exchange (ETDEWEB)

    Denisov, Dmitri [Fermilab, Batavia IL (United States); Evdokimov, Valery [Institute for High Energy Physics, Protvino (Russian Federation); Lukić, Strahinja; Ujić, Predrag [Vinča Institute, University of Belgrade (Serbia)

    2017-03-11

    Prototype scintilator+WLS strips with SiPM readout for large muon detection systems were tested in the muon beam of the Fermilab Test Beam Facility. Light yield of up to 137 photoelectrons per muon per strip has been observed , as well as time resolution of 330 ps and position resolution along the strip of 5.4 cm.

  7. Signal acquisition and scale calibration for beam power density distribution of electron beam welding

    Science.gov (United States)

    Peng, Yong; Li, Hongqiang; Shen, Chunlong; Guo, Shun; Zhou, Qi; Wang, Kehong

    2017-06-01

    The power density distribution of electron beam welding (EBW) is a key factor to reflect the beam quality. The beam quality test system was designed for the actual beam power density distribution of high-voltage EBW. After the analysis of characteristics and phase relationship between the deflection control signal and the acquisition signal, the Post-Trigger mode was proposed for the signal acquisition meanwhile the same external clock source was shared by the control signal and the sampling clock. The power density distribution of beam cross-section was reconstructed using one-dimensional signal that was processed by median filtering, twice signal segmentation and spatial scale calibration. The diameter of beam cross-section was defined by amplitude method and integral method respectively. The measured diameter of integral definition is bigger than that of amplitude definition, but for the ideal distribution the former is smaller than the latter. The measured distribution without symmetrical shape is not concentrated compared to Gaussian distribution.

  8. Literature in Focus Beta Beams: Neutrino Beams

    CERN Multimedia

    2009-01-01

    By Mats Lindroos (CERN) and Mauro Mezzetto (INFN Padova, Italy) Imperial Press, 2009 The beta-beam concept for the generation of electron neutrino beams was first proposed by Piero Zucchelli in 2002. The idea created quite a stir, challenging the idea that intense neutrino beams only could be produced from the decay of pions or muons in classical neutrino beams facilities or in future neutrino factories. The concept initially struggled to make an impact but the hard work by many machine physicists, phenomenologists and theoreticians over the last five years has won the beta-beam a well-earned position as one of the frontrunners for a possible future world laboratory for high intensity neutrino oscillation physics. This is the first complete monograph on the beta-beam concept. The book describes both technical aspects and experimental aspects of the beta-beam, providing students and scientists with an insight into the possibilities o...

  9. Beam Techniques - Beam Control and Manipulation

    Energy Technology Data Exchange (ETDEWEB)

    Minty, Michiko G

    2003-04-24

    We describe commonly used strategies for the control of charged particle beams and the manipulation of their properties. Emphasis is placed on relativistic beams in linear accelerators and storage rings. After a brief review of linear optics, we discuss basic and advanced beam control techniques, such as transverse and longitudinal lattice diagnostics, matching, orbit correction and steering, beam-based alignment, and linac emittance preservation. A variety of methods for the manipulation of particle beam properties are also presented, for instance, bunch length and energy compression, bunch rotation, changes to the damping partition number, and beam collimation. The different procedures are illustrated by examples from various accelerators. Special topics include injection and extraction methods, beam cooling, spin transport and polarization.

  10. Electron beam control for barely separated beams

    Science.gov (United States)

    Douglas, David R.; Ament, Lucas J. P.

    2017-04-18

    A method for achieving independent control of multiple beams in close proximity to one another, such as in a multi-pass accelerator where coaxial beams are at different energies, but moving on a common axis, and need to be split into spatially separated beams for efficient recirculation transport. The method for independent control includes placing a magnet arrangement in the path of the barely separated beams with the magnet arrangement including at least two multipole magnets spaced closely together and having a multipole distribution including at least one odd multipole and one even multipole. The magnetic fields are then tuned to cancel out for a first of the barely separated beams to allow independent control of the second beam with common magnets. The magnetic fields may be tuned to cancel out either the dipole component or tuned to cancel out the quadrupole component in order to independently control the separate beams.

  11. First observation of o-Ps to p-Ps transition and first direct measurement of positronium hyperfine splitting with sub-THz light

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, Takayuki, E-mail: yamazaki@icepp.s.u-tokyo.ac.jp; Miyazaki, Akira; Suehara, Taikan; Namba, Toshio; Asai, Shoji; Kobayashi, Tomio [University of Tokyo, Department of Physics, Graduate School of Science, and International Center for Elementary Particle Physics (Japan); Saito, Haruo [University of Tokyo, Graduate School of Arts and Sciences (Japan); Urushizaki, Yuichi; Ogawa, Isamu; Idehara, Toshitaka [University of Fukui, Research Center for Development of Far-Infrared Region (Japan); Sabchevski, Svilen [Bulgarian Academy of Sciences (Bulgaria)

    2012-12-15

    Positronium is an ideal system for the research of the bound state QED. The hyperfine splitting of positronium (Ps-HFS, about 203 GHz) is an important observable but all previous measurements of Ps-HFS had been measured indirectly using Zeeman splitting. There might be the unknown systematic errors on the uniformity of magnetic field. We are trying to measure Ps-HFS directly using sub-THz radiation. We developed an optical system to accumulate high power (about 10 kW) radiation in a Fabry-Perot resonant cavity and observed the positronium hyperfine transition for the first time.

  12. Dataset for the validation and use of DiameterJ an open source nanofiber diameter measurement tool

    Directory of Open Access Journals (Sweden)

    Nathan A. Hotaling

    2015-12-01

    Full Text Available DiameterJ is an open source image analysis plugin for ImageJ. DiameterJ produces ten files for every image that it analyzes. These files include the images that were analyzed, the data to create histograms of fiber radius, pore size, fiber orientation, and summary statistics, as well as images to check the output of DiameterJ. DiameterJ was validated with 130 in silico-derived, digital, synthetic images and 24 scanning electron microscope (SEM images of steel wire samples with a known diameter distribution. Once validated, DiameterJ was used to analyze SEM images of electrospun polymeric nanofibers, including a comparison of different segmentation algorithms. In this article, all digital synthetic images, SEM images, and their segmentations are included. Additionally, DiameterJ’s raw output files, and processed data is included for the reader. The data provided herein was used to generate the figures in DiameterJ: A Validated Open Source Nanofiber Diameter Measurement Tool [1], where more discussion can be found.

  13. Multiple reflected beam synthesis of fields excited by a high-frequency oblique beam input in an elastic plate.

    Science.gov (United States)

    Zeroug, S; Felsen, L B

    1992-04-01

    Transducer-excited beams provide important diagnostic tools for ultrasonic nondestructive evaluation (NDE) of elastic materials. For bonded multilayer elastic plates, an obliquely injected high-frequency compressional (P) beam creates interior dynamic fields that are sensitive to weak debonding between the layers. In an effort to clarify the wave phenomena that are operative under these conditions of excitation, a highly idealized model has been chosen wherein a lossless plate in vacuum is insonified by an internal oblique P-beam source. This problem was analyzed in a previous investigation [Lu, Felsen, and Klosner, J. Acoust. Soc. Am. 87, 42-53 (1990)] by expressing the total field in terms of a sum of P-S (vertically polarized or in-plane) coupled normal modes. While the resulting field assumed oscillatory modal patterns at interior cross sections far from the source region, the modally synthesized field near the source clearly outlined profiles interpretable as incident and singly or multiply reflected P-S coupled beams. The problem is therefore studied here directly by Gaussian beam tracing as implemented via our previously employed complex ray field algorithm. The results clarify the observed phenomena by revealing the successive buildup from initially well-resolved beams into oscillatory mode patterns synthesized by overlapping multiples. For the same idealized model, the beam algorithm has been applied elsewhere to the detection and identification of weak debonding in a layered plate [Felsen and Zeroug, J. Acoust. Soc. Am. 90, 1527-1538 (1991)]. With an understanding of the physical mechanisms that arise in the beam-to-mode conversion, one may now explore how their utility is affected under realistic NDE conditions.

  14. A DiPS+ case study: a self-healing RADIUS server

    OpenAIRE

    Michiels, Sam; Desmet, Lieven; Verbaeten, Pierre

    2004-01-01

    This report shows performance results of a RADIUS implementation using the DiPS+ software architecture. In addition it compares this implementation with a commercially available RADIUS implementation, and shows that the DiPS+ architecture differentiates between user types and request types. In fact, the DiPS+ prototype prioritizes incoming traffic based on application-specifc preferences, and allocates the available processing resources to the highest priority requests.

  15. The Cherenkov correlated timing detector beam test results from quartz and acrylic bars

    CERN Document Server

    Sugaya, Y; Yoshimura, Y; Kanda, S; Olsen, S; Ueno, K; Varner, G S; Bergfeld, T; Bialek, J J; Lorenc, J; Palmer, M; Rudnick, G; Selen, M; Auran, T; Boyer, V; Honscheid, K; Tamura, N; Yoshimura, K; Lü, C; Marlow, D R; Mindas, C R; Prebys, E J; Asai, M; Kimura, A; Hayashi, S

    1995-01-01

    Several prototypes of a Cherenkov Correlated Timing (CCT) Detector have been tested at the KEK-PS test beam line. We describe the results for Cherenkov light yields and timing characteristics from quartz and acrylic bar prototypes. A Cherenkov angle resolution is found to be 15 mrad at a propagation distance of 100 cm with a 2 cm thick quartz bar prototype.

  16. Results from the October 2014 CERN test beam of LumiCal

    CERN Document Server

    Borysov, O; Levy, A; Levy, I; Lukic, S; Moron, J; Neagu, A T; Preda, T; Rosenblat, O

    2016-01-01

    A prototype of a luminometer, designed for a future e+e- collider detector, was tested in the CERN PS accelerator T9 testbeam. The objective of this test beam was to demonstrate a multi-plane operation, to study the development of the electromagnetic shower and to compare it with MC simulations.

  17. Laser-frequency locking using light-pressure-induced spectroscopy in a calcium beam

    NARCIS (Netherlands)

    Mollema, A. K.; Wansbeek, L. W.; Willmann, L.; Jungmann, K.; Timmermans, R. G. E.; Hoekstra, R.

    We demonstrate a spectroscopy method that can be applied in an atomic beam, light-pressure-induced spectroscopy (LiPS). A simple pump and probe experiment yields a dispersivelike spectroscopy signal that can be utilized for laser frequency stabilization. The underlying principles are discussed and

  18. Ion beam profiling from the interaction with a freestanding 2D layer

    Directory of Open Access Journals (Sweden)

    Ivan Shorubalko

    2017-03-01

    Full Text Available Recent years have seen a great potential of the focused ion beam (FIB technology for the nanometer-scale patterning of a freestanding two-dimensional (2D layer. Experimentally determined sputtering yields of the perforation process can be quantitatively explained using the binary collision theory. The main peculiarity of the interaction between the ion beams and the suspended 2D material lies in the absence of collision cascades, featured by no interaction volume. Thus, the patterning resolution is directly set by the beam diameters. Here, we demonstrate pattern resolution beyond the beam size and precise profiling of the focused ion beams. We find out that FIB exposure time of individual pixels can influence the resultant pore diameter. In return, the pore dimension as a function of the exposure dose brings out the ion beam profiles. Using this method of determining an ion-beam point spread function, we verify a Gaussian profile of focused gallium ion beams. Graphene sputtering yield is extracted from the normalization of the measured Gaussian profiles, given a total beam current. Interestingly, profiling of unbeknown helium ion beams in this way results in asymmetry of the profile. Even triangular beam shapes are observed at certain helium FIB conditions, possibly attributable to the trimer nature of the beam source. Our method of profiling ion beams with 2D-layer perforation provides more information on ion beam profiles than the conventional sharp-edge scan method does.

  19. Growth process and diameter structure of Pinus tabulaeformis forest ...

    African Journals Online (AJOL)

    Using stem analysis method, the biomass, growing process and diameter structure of 21-year shady and sunny slope Pinus tabulaeformis forest were investigated in hilly loess-gully region. Results showed that there were distinct difference in the indexes, tree height, diameter at breast height (DBH) and timber volume ...

  20. Equipment for testing beds in small-diameter deep wells

    Energy Technology Data Exchange (ETDEWEB)

    Varlamov, P.S.; Lopatkin, O.P.; Snezhko, M.P.

    1978-03-01

    A description is given of the technical specifications of specially designed drill stem testor 80 mm in diameter which was developed for testing horizons in deep boreholes of small diameter. Also described is the operational efficiency of this equipment and the economic advantages derived from it.

  1. Relationships between stem diameter at breast height (DBH), tree ...

    African Journals Online (AJOL)

    Trees show considerable variation and flexibility in their size of crowns, height and stem diameter at breast height (dbh). Dbh has been used as predictor variables in diameter and height growth equations. Relationships between dbh, tree height, crown length, crown height and crown ratio of Vitellaria paradoxa were ...

  2. Parsimonious Crown Diameter Prediction Models for Tectona Grandis

    African Journals Online (AJOL)

    Parsimonious Crown Diameter Prediction Models for Tectona Grandis (Linn f Verbenaceae). FS Popo-ola, BA Oyebade,. Abstract. Tree crown is one complement of net primary production and its dimensions reflect general tree health. Crown diameter is often used as an important predictor variable for tree growth equation.

  3. Generalized height-diameter models for Populus tremula L. stands ...

    African Journals Online (AJOL)

    Using permanent sample plot data, selected tree height and diameter functions were evaluated for their predictive abilities for Populus tremula stands in Turkey. Two sets of models were evaluated. The first set included five models for estimating height as a function of individual tree diameter; the second set also included six ...

  4. Diameter Growth, Survival, and Volume Estimates for Missouri Trees

    Science.gov (United States)

    Stephen R. Shifley; W. Brad Smith

    1982-01-01

    Measurements of more than 20,000 Missouri trees were summarized by species and diameter class into tables of mean annual diameter growth, annual probability of survival, net cubic foot volume, and net board foot volume. In the absence of better forecasting techniques, this information can be utilized to project short-term changes for Missouri trees, inventory plots,...

  5. Sex differences in diameter of the coronary sinus ostium: Correlation ...

    African Journals Online (AJOL)

    Diameter of the coronary sinus ostium is important in the designing of cannulation devices used in cardiac resynchronization therapy and percutaneous mitral valve annuloplasty. Population variation of the diameter may account for the failure rate of these procedures. Studies of the coronary sinus ostium from African ...

  6. Sex Dimorphism of the Heart Diameters and Cardiothoracic Ratios ...

    African Journals Online (AJOL)

    Objective: To determine gender associated differences in the cardiothoracic ratio (CTR) and heart diameters in a normal Nigerian population. Subject and Method: The normal heart diameters and cardiothoracic ratios were measured from posteroanterior (PA) chest radiographs of healthy 510 male and 508 female ...

  7. Growth process and diameter structure of Pinus tabulaeformis forest ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... Using stem analysis method, the biomass, growing process and diameter structure of 21-year shady and sunny slope Pinus tabulaeformis forest were investigated in hilly loess-gully region. Results showed that there were distinct difference in the indexes, tree height, diameter at breast height (DBH).

  8. Influence of high intensity ultrasound with different probe diameter ...

    African Journals Online (AJOL)

    The main goal of this research is to analyze the influence of ultrasonic probe diameters (7 and 10 mm) of high-intensity ultrasound with constant frequency (30 kHz) on the degree of homogenization (variance) of cow milk. Influence of different probe diameters on the physical properties of cow milk was also tested. Changes ...

  9. Lumbar Vertebral Canal Diameters in Adult Ugandan Skeletons ...

    African Journals Online (AJOL)

    Background: Normal values of lumbar vertebral canal diameters are useful in facilitating diagnosis of lumbar vertebral canal stenosis. Various studies have established variation on values between different populations, gender, age, and ethnic groups. Objectives: To determine the lumbar vertebral canal diameters in adult ...

  10. Electron beam damage in high temperature polymers

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, S. (Dayton Univ., OH (USA). Research Inst.); Adams, W.W. (Air Force Materials Lab., Wright-Patterson AFB, OH (USA))

    1990-01-01

    Electron microscopic studies of polymers are limited due to beam damage. Two concerns are the damage mechanism in a particular material, and the maximum dose for a material before damage effects are observed. From the knowledge of the dose required for damage to the polymer structure, optimum parameters for electron microscopy imaging can be determined. In the present study, electron beam damage of polymers has been quantified by monitoring changes in the diffraction intensity as a function of electron dose. The beam damage characteristics of the following polymers were studied: poly(p-phenylene benzobisthiazole) (PBZT); poly(p-phenylene benzobisoxazole) (PBO); poly(benzoxazole) (ABPBO); poly(benzimidazole) (ABPBI); poly(p-phenylene terephthalamide) (PPTA); and poly(aryl ether ether ketone) (PEEK). Previously published literature results on polyethylene (PE), polyoxymethylene (POM), nylon-6, poly(ethylene oxide) (PEO), PBZT, PPTA, PPX, iPS, poly(butylene terephthalate) (PBT), and poly(phenylene sulphide) (PPS) were reviewed. This study demonstrates the strong dependence of the electron beam resistivity of a polymer on its thermal stability/melt temperature. (author).

  11. Design of a Phase /Doppler Light-Scattering System for Measurement of Small-Diameter Glass Fibers During Fiberglass Manufacturing

    Science.gov (United States)

    Schaub, Scott A.; Naqwi, Amir A.; Harding, Foster L.

    1998-01-01

    We present fundamental studies examining the design of a phase /Doppler laser light-scattering system applicable to on-line measurements of small-diameter ( fiberglass manufacturing. We first discuss off-line diameter measurement techniques currently used in the fiberglass industry and outline the limitations and problems associated with these methods. For the phase /Doppler design study we have developed a theoretical computer model for the response of the measurement system to cylindrical fibers, which is based on electromagnetic scattering theory. The model, valid for arbitrary fiber diameters and hardware configurations, generates simulated detector output as a function of time for a finite absorbing, cylindrical fiber oriented perpendicular to the two incident laser beams. Results of experimental measurements are presented, confirming predictions of the theoretical model. Parametric studies have also been conducted using the computer model to identify experimental arrangements that provide linear phase -diameter relationships for small-diameter fibers, within the measurement constraints imposed by the fiberglass production environment. The effect of variations in optical properties of the glass as well as fiber orientation effects are discussed. Through this research we have identified phase /Doppler arrangements that we expect to have future applications in the fiberglass industry for on-line diameter monitoring and process control.

  12. Use of sequential infiltration synthesis to improve the pattern transfer of PS-b-PLA DSA (Conference Presentation)

    Science.gov (United States)

    Evangelio Araujo, Laura; Fernández-Regúlez, Marta; Chevalier, Xavier; Nicolet, Célia; Cayrefourcq, Ian; Navarro, Christophe; Fleury, Guillaume; Pérez-Murano, Francesc

    2017-03-01

    locally modified by the combination of e-beam lithography and soft oxygen plasma. Afterwards, the PS-b-PLA block copolymer is spin-coated and thermally annealed on the chemically pre-patterned substrate. A chemical contrast is observed between the modified and unmodified stripes. While, the lamellar domains are oriented perpendicular to the substrate on unmodified areas, PLA domains are strongly attracted to the O2 modified surfaces inducing a parallel orientation to the substrate. Additionally, the wetting behavior of the polymer domains is also studied through the difference of surface free energy between the substrate and each polymer block. The energy estimated by the Younǵs equation [Δγ =γSA -γSB= γAB·cos(ØAB)], where γSA and γSB are the interface tensions between homo-polymers A and B with the substrate, and ØAB is the contact angle between A and B homo-polymers which is obtained in de-wetting experiments. Finally, sequential infiltration synthesis is used to selectively infiltrate alumina (Al3O2) on PLA domains (figure 2). A selective infiltration is achieved because the precursor molecules react with the carbonyl (C=O) groups that are only present in the PLA block. After five cycles of SIS, the SIS modified PLA domains become more resistant to O2 plasma etching than PS enabling the PS etching without using other kind of hard-masks. The research leading to these results received funding from the European Union's Seventh Framework Program FP7/2007-2013, under the project CoLiSA and the European Nanoelectronics Initiative Advisory Council under the project PLACYD (ENIAC-2013-2). L. Evangelio acknowledges MECD for the PhD contract FPU13/03746 [1] R. Ruiz, H. Kang, F. A. Detcheverry, E. Dobisz, D. S. Kercher, T. R. Albrecht, J. J. de Pablo, P. F. Nealey, Science 321 (2008) 936-939. [2] M. Fernández-Regúlez, L, Evangelio, M. Lorenzoni, J. Fraxedas, F. Perez-Murano, ACS Appl. Mater. Interfaces 6 (2014) 21596-21602. [3] L. Wan, R. Ruiz, H. Gao, K. C. Patel, T

  13. Telecommunication using muon beams

    Science.gov (United States)

    Arnold, Richard C.

    1976-01-01

    Telecommunication is effected by generating a beam of mu mesons or muons, varying a property of the beam at a modulating rate to generate a modulated beam of muons, and detecting the information in the modulated beam at a remote location.

  14. Nonparaxial abruptly autofocusing beams

    Science.gov (United States)

    Penciu, Raluca-Sorina; Makris, Konstantinos G.; Efremidis, Nikolaos K.

    2016-03-01

    We study nonparaxial autofocusing beams with pre-engineered trajectories. We consider the case of linearly polarized electric optical beams and examine their focusing properties such as contrast, beam width, and numerical aperture. Such beams are associated with larger intensity contrasts, can focus at smaller distances, and have smaller spot sizes as compared to the paraxial regime.

  15. ISR beam scrapers

    CERN Multimedia

    CERN PhotoLab

    1972-01-01

    Beam scrapers seen in the direction of the beam. The two horizontal scraper foils are near the centre of the beam pipe andthe two scrapers for protection of the vacuum chamber are further outside. In the lower part of the beam pipe is the vertical halo scraping blade.

  16. Microfabricated device for co-culture of sympathetic neuron and iPS-derived cardiomyocytes.

    Science.gov (United States)

    Takeuchi, Akimasa; Shimba, Kenta; Takayama, Yuzo; Kotani, Kiyoshi; Lee, Jong-Kook; Noshiro, Makoto; Jimbo, Yasuhiko

    2013-01-01

    Induced pluripotent stem (iPS) cell-derived cardiomyocytes (iPS-CMs) has been expected as a cell source for therapy of serious heart failure. However, it is unclear whether the function of iPS-CMs is modulated by the host sympathetic nervous system. Here we developed a device for co-culture of sympathetic neurons and iPS-CMs using microfabrication technique. The device consisted of a culture chamber and a microelectrode-array (MEA) substrate. The superior cervical ganglion (SCG) neurons were co-cultured with iPS-CMs in a microfabricated device, which had multiple compartments. Several days after seeding, synapses were formed between SCG neurons and iPS-CMs, as confirmed by immunostaining. Spontaneous electrical activities of the SCG neurons and the iPS-CMs were observed from the electrode of the MEA substrate. The beat rate of iPS-CMs increased after electrical stimulation of the co-cultured SCG neurons. Such changes in the beat rate were prevented in the presence of propranolol, a β-adrenoreceptor antagonist. These results suggest that the microfabricated device will be utilized for studying the functional modulation of iPS-CMs by connected sympathetic neurons.

  17. Facile Synthesis of Mono-Dispersed Polystyrene (PS/Ag Composite Microspheres via Modified Chemical Reduction

    Directory of Open Access Journals (Sweden)

    Wen Zhu

    2013-12-01

    Full Text Available A modified method based on in situ chemical reduction was developed to prepare mono-dispersed polystyrene/silver (PS/Ag composite microspheres. In this approach; mono-dispersed PS microspheres were synthesized through dispersion polymerization using poly-vinylpyrrolidone (PVP as a dispersant at first. Then, poly-dopamine (PDA was fabricated to functionally modify the surfaces of PS microspheres. With the addition of [Ag(NH32]+ to the PS dispersion, [Ag(NH32]+ complex ions were absorbed and reduced to silver nanoparticles on the surfaces of PS-PDA microspheres to form PS/Ag composite microspheres. PVP acted both as a solvent of the metallic precursor and as a reducing agent. PDA also acted both as a chemical protocol to immobilize the silver nanoparticles at the PS surface and as a reducing agent. Therefore, no additional reducing agents were needed. The resulting composite microspheres were characterized by TEM, field emission scanning electron microscopy (FESEM, energy-dispersive X-ray spectroscopy (EDS, XRD, UV-Vis and surface-enhanced Raman spectroscopy (SERS. The results showed that Ag nanoparticles (NPs were homogeneously immobilized onto the PS microspheres’ surface in the presence of PDA and PVP. PS/Ag composite microspheres were well formed with a uniform and compact shell layer and were adjustable in terms of their optical property.

  18. Lehtmets : psühhiaatria ei ole piisavalt atraktiivne / Andres Lehtmets ; interv. Marika Kusnets

    Index Scriptorium Estoniae

    Lehtmets, Andres

    2004-01-01

    Vestlus Eesti Psühhiaatrite Seltsi aseesimehega rahva vaimsest tervisest. Samas ka sotsiaalministeeriumi rahvatervise osakonna peaspetsialisti Helja Eomoisi kommentaar: Mida teeb ministeerium rahva vaimse tervise parandamiseks?

  19. Beam propagation model for the hazard evaluation of Gaussian laser beams

    Energy Technology Data Exchange (ETDEWEB)

    Schulmeister, K.; Althaus, S.; Grabner, U.; Vees, G. [ARC Seibersdorf Research (Austria)

    2004-07-01

    A beam propagation model was developed to calculate the most hazardous position, the angular subtense of the apparent source, and the power that passes through a 7 mm at that position for a Gaussian laser beam. The results for the thermal retinal hazard are discussed and it is shown that for most cases, at the most hazardous position, the beam waist can be treated as the apparent source. A number of distinctive regions of beam waist diameter and divergence values could be identified and the background of the results of the model could be explained and approximated well by simple formulas. Since the angular subtense of the beam waist (and therefore of the apparent source) decreases with increasing distance to the beam waist, the most hazardous position may not be at 10 cm from the beam waist but some distance away. Consequently, when the results of the model are compared with the accessible emission level and the emission limit that would be determined at 10 cm from the beam waist, as is currently implied in the international laser safety standard IEC 60825-1, then the latter would underestimate the hazard by up to a factor of 3.5. (orig.)

  20. BTF measurements with beam-beam interactions

    CERN Document Server

    Gorgen, P.; Fischer, W.

    2014-07-17

    We present considerations about the transverse beam transfer function (BTF) of beams under the influence of two effects: The strong-strong beam-beam effect and the influence of a Gaussian electron lens. The BTF are investigated using two methods: BTF excitation is simulated in a particle-in-cell (PIC) code. The BTF model is verified using a known analytic expectation. Analytic expectations for BTF of beams under a stationary electron lens are derived by extending BTF from the formalism of Berg and Ruggiero. Finally we compare the analytic BTF results for a stationary Gaussian lens to both the PIC simulation for split tune conditions and to PIC simulations for a beam influenced by an electron lens. We conclude that the formalism represents the electron lens well and can be applied to a limited extend to the beam-beam effect under split tune conditions. The analytic formalism allows us to recover the strength of an electron lens by means of fitting and can give clues regarding the strength of the beam-beam effe...

  1. Frequency domain synthetic aperture focusing technique for variable-diameter cylindrical components.

    Science.gov (United States)

    Jin, Haoran; Wu, Eryong; Han, Ye; Yang, Keji; Chen, Jian

    2017-09-01

    Ultrasonic non-destructive testing (UNDT) plays an important role in ensuring the quality of cylindrical components of equipment such as pipes and axles. As the acoustic beam width widens along propagation depths, the diffraction of acoustic wave becomes serious and the images of defects will be interfered with. To precisely evaluate the dimensions of defects and flaws concealed in components, the synthetic aperture focusing technique (SAFT) is introduced to enhance the image resolutions. Conventional SAFTs have been successfully implemented for the ultrasonic imaging of normal cylinders, while solutions for complex ones, such as variable-diameter cylinders, are still lacking. To overcome this problem, a frequency-domain SAFT for variable-diameter cylindrical components is proposed. This algorithm is mainly based on acoustic field extrapolation, which is modified from cylindrical phase shift migration with the aid of split-step Fourier. After a series of extrapolations, a high-resolution ultrasound image can be reconstructed using a particular imaging condition. According to the experimental results, the proposed method yields low side lobes and high resolutions for flat transducers. Its attainable angular resolution relies on the transducer diameter D and scanning radius R and approximates D/(2R).

  2. Molecular characterization of plasmids pS7a and pS7b from Lactococcus lactis subsp. lactis bv. diacetylactis S50 as a base for the construction of mobilizable cloning vectors.

    Science.gov (United States)

    Strahinic, I; Kojic, M; Tolinacki, M; Fira, D; Topisirovic, L

    2009-01-01

    Strain Lactococcus lactis subsp. lactis bv. diacetylactis S50 harbours five theta-replicating plasmids (pS6, pS7a, pS7b, pS80 and pS140). The aim of this study was to characterize domains involved in the replication and conjugative mobilization of the small plasmids pS7a and pS7b, which are structurally very similar. Complete nucleotide sequences of pS7a and pS7b were determined by cloning DNA fragments of different sizes into Escherichia coli vectors. Linearized plasmids and four EcoRI fragments of the pS7a and pS7b were cloned into an origin probe vector. Constructed plasmids (pSEV10, pSK10, pISE1a and pISE1b) were able to replicate in the strain L. lactis subsp. cremoris MG1363. In addition, experiments showed that plasmids pS7a and pS7b contained oriT sequences and their conjugative transfer directly depended on the presence of pS80 in donor cells. Plasmids pS7a and pS7b contained typical lactococcal theta replication origin and repB gene that enable them to replicate in the strain L. lactis subsp. cremoris MG1363. Plasmid pS80 plays a key role in the conjugative transfer of small plasmids. Plasmids pS7a and pS7b-based derivatives could be valuable tools for genetic manipulation, studying processes of plasmid maintenance and horizontal gene transfer in lactococci.

  3. The beam dump tunnels

    CERN Multimedia

    Patrice Loïez

    2002-01-01

    In these images workers are digging the tunnels that will be used to dump the counter-circulating beams. Travelling just a fraction under the speed of light, the beams at the LHC will each carry the energy of an aircraft carrier travelling at 12 knots. In order to dispose of these beams safely, a beam dump is used to extract the beam and diffuse it before it collides with a radiation shielded graphite target.

  4. Phase space generation for proton and carbon ion beams for external users’ applications at the Heidelberg Ion Therapy Center

    Directory of Open Access Journals (Sweden)

    Thomas eTessonnier

    2016-01-01

    Full Text Available In the field of radiation therapy, accurate and robust dose calculation is required. For this purpose, precise modeling of the irradiation system and reliable computational platforms are needed. At the Heidelberg Ion Therapy Center (HIT, the beamline has been already modeled in the FLUKA Monte Carlo code. However, this model was kept confidential for disclosure reasons and was not available for any external team. The main goal of this study was to create efficiently phase space (PS files for proton and carbon ion beams, for all energies and foci available at HIT. PS are representing the characteristics of each particle recorded (charge, mass, energy, coordinates, direction cosines, generation at a certain position along the beam path. In order to achieve this goal, keeping a reasonable data size but maintaining the requested accuracy for the calculation, we developed a new approach of beam PS generation with the Monte-Carlo code FLUKA. The generated PS were obtained using an infinitely narrow beam and recording the desired quantities after the last element of the beamline, with a discrimination of primaries or secondaries. In this way, a unique PS can be used for each energy to accommodate the different foci by combining the narrow-beam scenario with a random sampling of its theoretical Gaussian beam in vacuum. PS can also reproduce the different patterns from the delivery system, when properly combined with the beam scanning information. MC simulations using PS have been compared to simulations including the full beamline geometry and have been found in very good agreement for several cases (depth dose distributions, lateral dose profiles, with relative dose differences below 0.5%. This approach has also been compared with measured data of ion beams with different energies and foci, resulting in a very satisfactory agreement. Hence, the proposed approach was able to fulfill the different requirements and has demonstrated its capability for

  5. Dental Implant Length and Diameter: A Proposed Classification Scheme.

    Science.gov (United States)

    Al-Johany, Sulieman S; Al Amri, Mohammad D; Alsaeed, Suliman; Alalola, Bassam

    2017-04-01

    To propose a length-and-diameter-based classification scheme for dental implants to standardize terminology in the dental literature and communication between interested parties. This study was mainly based on searching two major resources: published scientific research papers and 14 of the most popular dental implant manufacturers. Indexed databases were searched from January 2004 up to and including February 2016 using the keywords "dental implant length" and "dental implant diameter." Retrieved titles and abstracts were screened, and related full-text articles were reviewed. Full-text articles that clearly stated the terms and measurements of implants used were included and considered for proposing this classification scheme. The initial search for implant diameter and length yielded 1007 and 936 articles, respectively. A total of 85 studies (41 about diameter, 44 about length) were selected and reviewed. The remaining studies (966 about diameter, 892 about length) that did not abide by the eligibility criteria were excluded. The terms "long," "short," "standard," "wide," and "narrow" were the most commonly used terms in the literature. A classification scheme for implants by diameter and length was proposed. Indexed publications contain a variety of terms used by authors to describe diameter and length of dental implants without conformity and standardization. The classification scheme proposed in this article could serve as a reference for interested parties. © 2016 by the American College of Prosthodontists.

  6. Ultra thin coherent atom beam by Stern-Gerlach interferometry

    Science.gov (United States)

    Perales, F.; Robert, J.; Baudon, J.; Ducloy, M.

    2007-06-01

    It is demonstrated that a Stern-Gerlach interferometer including a special transverse phase shifter can generate an atomic beam of a small diameter (few tens of nm). Calculations carried out in a coherent regime confirm this point. They also show that the device is almost insensitive to velocity dispersion and that the required mechanical accuracy is quite accessible. Due to the peculiar transverse amplitude distribution (of the Lorentz type), the spreading of the generated beam profile is very small compared to that given by a circular diaphragm or a Gaussian profile of comparable initial diameter. This is a key property as regards applications, e.g. in atom lithography and surface probing.

  7. Neural stem cells differentiated from iPS cells spontaneously regain pluripotency.

    Science.gov (United States)

    Choi, Hyun Woo; Kim, Jong Soo; Choi, Sol; Hong, Yean Ju; Kim, Min Jung; Seo, Han Geuk; Do, Jeong Tae

    2014-10-01

    Differentiated somatic cells can be reprogrammed into pluripotent stem cells by transduction of exogenous reprogramming factors. After induced pluripotent stem (iPS) cells are established, exogenous genes are silenced. In the pluripotent state, retroviral genes integrated in the host genome are kept inactive through epigenetic transcriptional regulation. In this study, we tried to determine whether exogenous genes remain silenced or are reactivated upon loss of pluripotency or on differentiation using an in vitro system. We induced differentiation of iPS cells into neural stem cells (NSCs) in vitro; the NSCs appeared morphologically indistinguishable from brain-derived NSCs and stained positive for the NSC markers Nestin and Sox2. These iPS cell-derived NSCs (iPS-NSCs) were also capable of differentiating into all three neural subtypes. Interestingly, iPS-NSCs spontaneously formed aggregates on long-term culture and showed reactivation of the Oct4-GFP marker, which was followed by the formation of embryonic stem cell-like colonies. The spontaneously reverted green fluorescent protein (GFP)-positive (iPS-NSC-GFP(+) ) cells expressed high levels of pluripotency markers (Oct4 and Nanog) and formed germline chimeras, indicating that iPS-NSC-GFP(+) cells had the same pluripotency as the original iPS cells. The reactivation of silenced exogenous genes was tightly correlated with the downregulation of DNA methyltransferases (Dnmts) during differentiation of iPS cells. This phenomenon was not observed in doxycycline-inducible iPS cells, where the reactivation of exogenous genes could be induced only by doxycycline treatment. These results indicate that pluripotency can be regained through reactivation of exogenous genes, which is associated with dynamic change of Dnmt levels during differentiation of iPS cells. © 2014 AlphaMed Press.

  8. Phosphorene-directed self-assembly of asymmetric PS-b-PMMA block copolymer for perpendicularly-oriented sub-10 nm PS nanopore arrays

    Science.gov (United States)

    Zhang, Ziming; Zheng, Lu; Khurram, Muhammad; Yan, Qingfeng

    2017-10-01

    Few-layer black phosphorus, also known as phosphorene, is a new two-dimensional material which is of enormous interest for applications, mainly in electronics and optoelectronics. Herein, we for the first time employ phosphorene for directing the self-assembly of asymmetric polystyrene-block-polymethylmethacrylate (PS-b-PMMA) block copolymer (BCP) thin film to form the perpendicular orientation of sub-10 nm PS nanopore arrays in a hexagonal fashion normal to the interface. We experimentally demonstrate that none of the PS and PMMA blocks exhibit preferential affinity to the phosphorene-modified surface. Furthermore, the perpendicularly-oriented PS nanostructures almost stay unchanged with the variation of number of layers of few-layer phosphorene nanoflakes between 15-30 layers. Differing from the neutral polymer brushes which are widely used for chemical modification of the silicon substrate, phosphorene provides a novel physical way to control the interfacial interactions between the asymmetric PS-b-PMMA BCP thin film and the silicon substrate. Based on our results, it is possible to build a new scheme for producing sub-10 nm PS nanopore arrays oriented perpendicularly to the few-layer phosphorene nanoflakes. Furthermore, the nanostructural microdomains could serve as a promising nanolithography template for surface patterning of phosphorene nanoflakes.

  9. Systematic review on success of narrow-diameter dental implants.

    Science.gov (United States)

    Klein, Marc O; Schiegnitz, Eik; Al-Nawas, Bilal

    2014-01-01

    The aim of this systematic review was to determine the survival and success rates of narrow-diameter implants (NDI) in different clinical indications compared to standard diameter implants. Implant diameters were categorized into categories 1 (implant diameters implant diameters 3 to 3.25 mm (Category 2), and 16 articles reporting on implant diameters 3.3 to 3.5 mm (Category 3). The quality of the studies was mostly low with a high risk of bias. Dental implants implants) were one-piece in the edentulous arch and non-loaded frontal region with survival rates between 90.9% and 100%. For dental implants with a diameter between 3.0 and 3.25 mm, most were two-piece implants inserted into narrow tooth gaps without loading and in the frontal region. Survival rates for these implants ranged between 93.8% and 100%. Implants of 3.3 to 3.5 mm were two-piece and were also used in the load-bearing posterior region. Survival rates were between 88.9% and 100%, and success rates ranged between 91.4% and 97.6%. A meta-analysis was conducted for NDI (3.3 to 3.5 mm), which showed no statistically significant difference in implant survival compared to conventional implants with an odds ratio of 1.16 (0.7 to 1.69). Narrow-diameter implants of 3.3 to 3.5 mm are well documented in all indications including load-bearing posterior regions. Smaller implants of 3.0 to 3.25 mm in diameter are well documented only for single-tooth non-load-bearing regions. Mini-implants 1 year and information on patient specific risk factors (bruxism, restoration type) are also missing.

  10. Beam Tests of a New Digital Beam Control System for the CERN LEIR Accelerator

    CERN Document Server

    Angoletta, Maria Elena; Blas, Alfred; De Long, Joseph; Findlay, Alan; Matuszkiewicz, Pawel; Pedersen, Flemming; Salom-Sarasqueta, Angela

    2005-01-01

    The Low Energy Ion Ring (LEIR) is a major component in the Large Hadron Collider ion injector chain. We have been developing an all-digital beam control and cavity servo system for the RF acceleration in LEIR. The system is housed by VME motherboards that may hold various daughter boards. Fast tasks are executed in Field Programmable Gate Arrays (FPGAs), slower tasks and communication with the software layer above are achieved in Digital Signal Processors (DSPs). We describe a simplified system prototype, which we tested with low intensity beams on the CERN PS Booster (PSB). The aim was to verify the combined DSP+FPGA architecture and the feedback loop dynamics. An additional goal was to deploy and validate novel software concepts, such as reference-functions and timings generation, and user-selectable digital data acquisition.

  11. Laser direct writing using submicron-diameter fibers.

    Science.gov (United States)

    Tian, Feng; Yang, Guoguang; Bai, Jian; Xu, Jianfeng; Hou, Changlun; Liang, Yiyong; Wang, Kaiwei

    2009-10-26

    In this paper, a novel direct writing technique using submicron-diameter fibers is presented. The submicron-diameter fiber probe serves as a tightly confined point source and it adopts micro touch mode in the process of writing. The energy distribution of direct writing model is analyzed by Three-Dimension Finite-Difference Time-Domain method. Experiments demonstrate that submicron-diameter fiber direct writing has some advantages: simple process, 350-nm-resolution (lower than 442-nm-wavelength), large writing area, and controllable width of lines. In addition, by altering writing direction of lines, complex submicron patterns can be fabricated.

  12. Heritability of retinal vessel diameters and blood pressure

    DEFF Research Database (Denmark)

    Taarnhøj, Nina C B B; Larsen, Michael; Sander, Birgit

    2006-01-01

    for CRVE, and 0.67 +/- 0.05 microm for AVR. No significant influence on artery or vein diameters was found for gender, smoking, body mass index (BMI), total cholesterol, fasting blood glucose, or 2-hour oral glucose tolerance test values. CONCLUSIONS: In healthy young adults with normal blood pressure...... and blood glucose, variations in retinal blood vessel diameters and blood pressure were predominantly attributable to genetic effects. A genetic influence may have a role in individual susceptibility to hypertension and other vascular diseases. The results suggest that retinal vessel diameters...

  13. Computing Graph Distances Parameterized by Treewidth and Diameter

    OpenAIRE

    Husfeldt, Thore

    2017-01-01

    We show that the eccentricity of every vertex in an undirected graph on n vertices can be computed in time n exp O(k*log(d)), where k is the treewidth of the graph and d is the diameter. This means that the diameter and the radius of the graph can be computed in the same time. In particular, if the diameter is constant, it can be determined in time n*exp(O(k)). This result matches a recent hardness result by Abboud, Vassilevska Williams, and Wang [SODA 2016] that shows that under the Strong E...

  14. Ball lightning diameter-lifetime statistical analysis of SKB databank

    Science.gov (United States)

    Amirov, Anvar Kh; Bychkov, Vladimir L.

    1995-03-01

    Revelation of the significance of diameter as a factor for the lifetime as a parameter for different ways of Ball Lightning (BL) disappearance has been made. Methods for non-parametric regression analysis have been applied for pairs diameter - radiation losses in correspondence to BL disappearance. BL diameter as a factor turned out to be significant for BL life-time in the case of explosion and decay and insignificant in the case of extinction. Dependence logarithm of radiation losses - logarithm of BL volume obtained with the help of nonparametric regression treatment turned out to be different according to BL ways of disappearance.

  15. Beam-smoothing investigation on Heaven I

    Science.gov (United States)

    Xiang, Yi-huai; Gao, Zhi-xing; Tong, Xiao-hui; Dai, Hui; Tang, Xiu-zhang; Shan, Yu-sheng

    2007-01-01

    Directly driven targets for inertial confinement fusion (ICF) require laser beams with extremely smooth irradiance profiles to prevent hydrodynamic instabilities that destroy the spherical symmetry of the target during implosion. Such instabilities can break up and mix together the target's wall and fuel material, preventing it from reaching the density and temperature required for fusion ignition. 1,2 Measurements in the equation of state (EOS) experiments require laser beams with flat-roofed profiles to generate uniform shockwave 3. Some method for beam smooth, is thus needed. A technique called echelon-free induced spatial incoherence (EFISI) is proposed for producing smooth target beam profiles with large KrF lasers. The idea is basically an image projection technique that projects the desired time-averaged spatial profile onto the target via the laser system, using partially coherent broadband lighe. Utilize the technique, we developing beam- smoothing investigation on "Heaven I". At China Institute of Atomic Energy , a new angular multiplexing providing with beam-smoothing function has been developed, the total energy is 158J, the stability of energy is 4%, the pulse duration is 25ns, the effective diameter of focusing spot is 400um, and the ununiformity is about 1.6%, the power density on the target is about 3.7×10 12W/cm2. At present, the system have provided steady and smooth laser irradiation for EOS experiments.

  16. Injection Bump Synchronization Study for the CERN PS

    CERN Document Server

    Serluca, Maurizio; Gilardoni, Simone; CERN. Geneva. ATS Department

    2016-01-01

    In the framework of the LHC Injector Upgrade (LIU) project the CERN PS injection kinetic energy will be upgraded from 1.4 to 2 GeV. The present injection bump is made by four bumpers in Straight Section (SS) 40, 42, 43, 44 and it will be converted in a five bumpers system to allow additional flexibility in the bump shape with a reduction of the proton losses during the bump closure. The injection section SS42 has being redesigned to accommodate a new eddy current septum which will host a new bumper magnet in the same vacuum vessel due to reduced longitudinal space availability. The synchronization and amplitude variation of the power converter of the in-vacuum bumper 42 with respect to the remaining outside vacuum bumpers 40, 41, 43, 44 can lead to orbit distortion and consequent losses during injection. In this note we present the experimental results from Machine Development (MD) studies along with simulations for the present system at 1.4 GeV to quantify the acceptable orbit distortion and the performance ...

  17. Scanning SQUID sampler with 40-ps time resolution

    Science.gov (United States)

    Cui, Zheng; Kirtley, John R.; Wang, Yihua; Kratz, Philip A.; Rosenberg, Aaron J.; Watson, Christopher A.; Gibson, Gerald W.; Ketchen, Mark B.; Moler, Kathryn. A.

    2017-08-01

    Scanning Superconducting QUantum Interference Device (SQUID) microscopy provides valuable information about magnetic properties of materials and devices. The magnetic flux response of the SQUID is often linearized with a flux-locked feedback loop, which limits the response time to microseconds or longer. In this work, we present the design, fabrication, and characterization of a novel scanning SQUID sampler with a 40-ps time resolution and linearized response to periodically triggered signals. Other design features include a micron-scale pickup loop for the detection of local magnetic flux, a field coil to apply a local magnetic field to the sample, and a modulation coil to operate the SQUID sampler in a flux-locked loop to linearize the flux response. The entire sampler device is fabricated on a 2 mm × 2 mm chip and can be scanned over macroscopic planar samples. The flux noise at 4.2 K with 100 kHz repetition rate and 1 s of averaging is of order 1 mΦ0. This SQUID sampler will be useful for imaging dynamics in magnetic and superconducting materials and devices.

  18. Beam diagnostics for low energy beams

    Directory of Open Access Journals (Sweden)

    J. Harasimowicz

    2012-12-01

    Full Text Available Low-energetic ion and antimatter beams are very attractive for a number of fundamental studies. The diagnostics of such beams, however, is a challenge due to low currents down to only a few thousands of particles per second and significant fraction of energy loss in matter at keV beam energies. A modular set of particle detectors has been developed to suit the particular beam diagnostic needs of the ultralow-energy storage ring (USR at the future facility for low-energy antiproton and ion research, accommodating very low beam intensities at energies down to 20 keV. The detectors include beam-profile monitors based on scintillating screens and secondary electron emission, sensitive Faraday cups for absolute intensity measurements, and capacitive pickups for beam position monitoring. In this paper, the design of all detectors is presented in detail and results from beam measurements are shown. The resolution limits of all detectors are described and options for further improvement summarized. Whilst initially developed for the USR, the instrumentation described in this paper is also well suited for use in other low-intensity, low-energy accelerators, storage rings, and beam lines.

  19. Performance assesment of pre-series beam wire scanner prototypes for the LHC injectors upgrade

    CERN Document Server

    AUTHOR|(CDS)2243534

    The BEAM department (BE), is in charge of the development and operation of the accelerator components. Inside this department, the Beam Instrumentation group (BE-BI) works on the instruments that allows the operators and scientists to observe the accelerated beam and its characteristics. Finally, the Profile Measurement section (BE-BI-PM) deals with all the instruments capable of measuring the particles transverse distribution (often called transverse beam profile). Among the different systems developed and maintained by the section, the Beam Wire Scanners (BWS) are particularly relevant, because ensures the accurate beam profile measurements in all the circular accelerators and serves as calibration for other instruments. A total of 31 BWS are installed in the PS, PSB, SPS and LHC (see Fig. 1 to recognize the different accelerators). All of these instruments present a different design, depending on their location, and are not satisfying the HL-LHC needs. In order to harmonize the CERN’s BWS with a single d...

  20. Electron-cloud simulation studies for the CERN-PS in the framework of the LHC Injectors Upgrade project

    CERN Document Server

    Rioja Fuentelsaz, Sergio

    The present study aims to provide a consistent picture of the electron cloud effect in the CERN Proton Synchrotron (PS) and to investigate possible future limitations due to the requirements foreseen by the LHC Injectors Upgrade (LIU) project. It consists of a complete simulation survey of the electron cloud build-up in the different beam pipe sections of the ring depending on several controllable beam parameters and vacuum chamber surface properties, covering present and future operation parameters. As the combined function magnets of the accelerator constitute almost the $80\\%$ in length of the ring, the implementation of a new feature for the simulation of any external magnetic field on the PyECLOUD code, made it possible to perform this study. All the results of the simulations are given as a function of the vacuum chamber surface properties in order to deduce them, both locally and globally, when compared with experimental data. In a first step, we characterize locally the maximum possible number of ...

  1. Electron Beam Source for Technological Applications

    Science.gov (United States)

    Polyakov, V. A.; Shchedrin, I. S.

    1997-05-01

    Electron beam source with thermionic cathode and its application for technological purposes are described.Three electrode electron gun has a lanthanum hexaboride disc emitter with indirect heating. Accelerating voltage can be varied from 20 to 100 kV.Maximum d.c. current is 1-2 A for emitter diameter 4-5 mm.Magnetic focusing lens of solenoidal type ensures high beam power density on the object processed - up to 10 MW per sq.sm.This electron source was used for welding and thermoprocessing - surface hardening of ball-bearings. To ensure required complex power distribution on their surface special electronic unit for electron beam position control was designed.At the surface of ball-bearings the layer with hardness of 62-64 HRC and thickness about 1-1.5 mm was formed after electron processing that considerably increased their working period.

  2. The directed differentiation of human iPS cells into kidney podocytes.

    Directory of Open Access Journals (Sweden)

    Bi Song

    Full Text Available The loss of glomerular podocytes is a key event in the progression of chronic kidney disease resulting in proteinuria and declining function. Podocytes are slow cycling cells that are considered terminally differentiated. Here we provide the first report of the directed differentiation of induced pluripotent stem (iPS cells to generate kidney cells with podocyte features. The iPS-derived podocytes share a morphological phenotype analogous with cultured human podocytes. Following 10 days of directed differentiation, iPS podocytes had an up-regulated expression of mRNA and protein localization for podocyte markers including synaptopodin, nephrin and Wilm's tumour protein (WT1, combined with a down-regulation of the stem cell marker OCT3/4. In contrast to human podocytes that become quiescent in culture, iPS-derived cells maintain a proliferative capacity suggestive of a more immature phenotype. The transduction of iPS podocytes with fluorescent labeled-talin that were immunostained with podocin showed a cytoplasmic contractile response to angiotensin II (AII. A permeability assay provided functional evidence of albumin uptake in the cytoplasm of iPS podocytes comparable to human podocytes. Moreover, labeled iPS-derived podocytes were found to integrate into reaggregated metanephric kidney explants where they incorporated into developing glomeruli and co-expressed WT1. This study establishes the differentiation of iPS cells to kidney podocytes that will be useful for screening new treatments, understanding podocyte pathogenesis, and offering possibilities for regenerative medicine.

  3. Emission properties of porphyrin compounds in new polymeric PS:CBP host

    Science.gov (United States)

    Jafari, Mohammad Reza; Bahrami, Bahram

    2015-06-01

    In this study, a device with fundamental structure of ITO/PEDOT:PSS (60 nm)/PS:CBP (70 nm)/Al (150 nm) was fabricated. The electroluminescence spectrum of device designated a red shift rather than PS:CBP photoluminescence spectra. It can be suggested that the electroplex emission occurs at PS:CBP interface. By following this step, red light-emitting devices using porphyrin compounds as a red dopant in a new host material PS:CBP with a configuration of ITO/PEDOT:PSS (60 nm)/PS:CBP:porphyrin compounds(70 nm)/Al (150 nm) have been fabricated and investigated. The electroluminescent spectra of the porphyrin compounds were red-shifted as compared with the PS:CBP blend. OLED devices based on doping 3,4PtTPP and TPPNO2 in PS:CBP showed purer red emission compared with ZnTPP and CoTPP doped devices. We believe that the electroluminescence performance of OLED devices based on porphyrin compounds depends on overlaps between the absorption of the porphyrin compounds and the emission of PS:CBP.

  4. Composite Si/PS membrane pressure sensors with micro and macro ...

    Indian Academy of Sciences (India)

    Porous Silicon (PS) is a versatile material with many unique features making it viable in the field of Microelectromechanical Systems (MEMS). In this paper, we discuss the optimization of formation parameters of micro and macro PS with different porosity and thickness for use in pressure sensors. The optimized material is ...

  5. Sonication-assisted synthesis of polystyrene (PS)/organoclay nanocomposites: influence of clay content

    Science.gov (United States)

    Suresh, Kelothu; Kumar, R. Vinoth; Kumar, Manish; Jeyapriya, M.; Anbarasan, R.; Pugazhenthi, G.

    2017-06-01

    This article presents the synthesis of a series of polystyrene (PS)/organoclay nanocomposite films consisting of different contents of clay (1-7 wt%) by sonication-coupled solvent-blending technique. The prepared PS nanocomposite films were characterized using various techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and thermal gravimetric analysis (TGA). The XRD and TEM results revealed the formation of exfoliated nanocomposites at lower loading of organoclay (<5 wt%). The presence of various functional groups in the organoclay and PS/organoclay nanocomposite was verified by FTIR spectra. The thermal stability of PS nanocomposites was significantly improved as compared to pristine PS, which is evident from TGA analysis. When 10% mass loss was chosen as a point of reference, the thermal degradation temperature of PS nanocomposite holding 7 wt% of organoclay was found to be 30 °C more over pristine PS. The thermal kinetic parameters such as activation energy ( E a), pre-exponential factor ( A), and the order of reaction ( n) were determined by employing the Coats-Redfern model. Thermal degradation reaction mechanism of PS nanocomposites was also investigated.

  6. [Methionine metabolism regulates maintenance and differentiation of human ES/iPS cells].

    Science.gov (United States)

    Shiraki, Nobuaki; Kume, Shoen

    2015-05-01

    Embryonic stem (ES) and induced pluripotent stem (iPS) cells are pluripotent and can give rise to all cell types. ES/iPS cells have a unique transcriptional circuit that sustains the pluripotent state. These cells also possess a characteristically high rate of proliferation as well as an abbreviated G1 phase. These unique molecular properties distinguish ES and iPS cells from somatic cells. Mouse ES/iPS cells are in a high-flux metabolic state, with a high dependence on threonine catabolism. However, little is known about amino acid metabolism in human ES/iPS cells. Recently, we reported that human ES/iPS cells require high amounts of methionine (Met) and express high levels of Met metabolism enzymes (Shriaki N, et al: Cell Metabolism, 2014). Met deprivation results in a rapid decrease in intracellular S-adenosyl-methionine (SAM), triggering the activation of p53 signaling, reducing pluripotent marker gene NANOG expression, and poising human ES/iPS cells for differentiation, follow by potentiated differentiation into all three germ layers. However, when exposed to prolonged Met deprivation, the cells went to apoptosis. In this review, we explain the importance of SAM in Met metabolism and its relationship with pluripotency, cell survival, and differentiation of human ES/iPS cells.

  7. Effects of hypoxia on pluripotency in murine iPS cells.

    Science.gov (United States)

    Sugimoto, Kouji; Yoshizawa, Yuu; Yamada, Shizuka; Igawa, Kazunari; Hayashi, Yoshihiko; Ishizaki, Hidetaka

    2013-10-01

    Retroviral transduction of four transcription factors (Oct4, Sox2, Klf4 and c-Myc) or three factors, excluding c-Myc, has been shown to initiate a reprogramming process that results in the transformation of murine fibroblasts to induced pluripotent stem (iPS) cells, and there has been a rapid increase in the number of iPS cell-based preclinical trials. In this study, the effects of these transcription factors were evaluated regarding the growth and differentiation of murine iPS cells under hypoxia. Based on the results of RT-PCR and alizarin red S staining, there were no statistical differences in the growth and differentiation of iPS cells or the induction of iPS cells to osteoblasts under hypoxia between the transcription factor groups. Furthermore, the function of hypoxia inducible factors (HIFs) in murine iPS cells under hypoxia was investigated in relation to the morphology and expression of transcription factors using RT-PCR and Western blotting. The HIF-2α knockdown group exhibited a decrease in the colony size of the iPS cells. The HIF-2α or -3α knockdown group demonstrated a statistically significant decrease in the transcription factor expression compared to that observed in the control group. These results demonstrate that HIF-2α among HIFs is the most influential candidate for the maintenance of the pluripotency of murine iPS cells. Copyright © 2013 Wiley Periodicals, Inc.

  8. 7 CFR 1753.37 - Plans and specifications (P&S).

    Science.gov (United States)

    2010-01-01

    ....37 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE... Installation of Central Office Equipment § 1753.37 Plans and specifications (P&S). (a) General. (1) Prior to... central office equipment. (2) The P&S shall specify the delivery and completion time required for each...

  9. Rahuoperatsioonide Keskuses alustab sotsiaalse ja psühholoogilise toetuse sektsioon / Merle Tihaste, Marge Sillaste

    Index Scriptorium Estoniae

    Parmak, Merle, 1968-

    2008-01-01

    Missioonidel osalevatele või pikaajalises lähetuses viibivatele kaitseväelastele ja nende peredele suunatud sotsiaalse ja psühholoogilise toetuse tagamiseks loodud sektsioonist Rahuoperatsioonide Keskuse koosseisus. Sektsiooni töömudelist, ülesannetest ja koostöövõrgustikust. Skeem: Sotsiaalse ja psühholoogilise toetuse sektsiooni töömudel ja partnerid

  10. PS Dreyer: Bakens op die pad van die wetenskap | Antonites | HTS ...

    African Journals Online (AJOL)

    PS Dreyer: Beacons on the path of science. Professor PS Dreyer is an academic who has shovsm insight and vision into several problems of the human sciences since 1951. He has identified problems, but also contributed solutions to them. In this respect his philosophy on causality and freedom is of utmost importance.

  11. M2 quality factor as a key to mastering laser beam propagation

    Science.gov (United States)

    Bouafia, Mohamed; Bencheikh, Halim; Bouamama, Larbi; Weber, Horst

    2004-09-01

    One of the most important properties of a laser resonator is the highly collimated or spatially coherent nature of the laser output beam. The spatial beam quality of the output beam, namely beam diameter and propagation factor M2 are critical parameters in a wide range of practical laser applications. This is because the spatial beam quality determines how tightly the beam can be focused or how well the beam propagates over long distances without significant spreading. It was investigated by many authors in previous years how to define and on how to measure the laser beam quality. An ISO working Draft Committee has also been organized to set-up a standard for definitions and test methods of the laser beam quality. In this work, the quality factor is studied with different methods.

  12. Preliminary Evaluation of PS300: A New Self-Lubricating High Temperature Composite Coating for Use to 800 C

    Science.gov (United States)

    Dellacorte, C.; Edmonds, B. J.

    1995-01-01

    This paper introduces PS300, a plasma sprayed, self-lubricating composite coating for use in sliding contacts at temperatures to 800 C. PS300 is a metal bonded chrome oxide coating with silver and BaF2/CaF2 eutectic solid lubricant additives. PS300 is similar to PS200, a chromium carbide based coating, which is currently being investigated for a variety of tribological applications. In pin-on-disk testing up to 650 C, PS300 exhibited comparable friction and wear properties to PS200. The PS300 matrix, which is predominantly chromium oxide rather than chromium carbide, does not require diamond grinding and polishes readily with silicon carbide abrasives greatly reducing manufacturing costs compared to PS200. It is anticipated that PS300 has potential for sliding bearing and seal applications in both aerospace and general industry.

  13. Porosity Assessment for Different Diameters of Coir Lignocellulosic Fibers

    Science.gov (United States)

    da Luz, Fernanda Santos; Paciornik, Sidnei; Monteiro, Sergio Neves; da Silva, Luiz Carlos; Tommasini, Flávio James; Candido, Verônica Scarpini

    2017-10-01

    The application of natural lignocellulosic fibers (LCFs) in engineering composites has increased interest in their properties and structural characteristics. In particular, the inherent porosity of an LCF markedly affects its density and the adhesion to polymer matrices. For the first time, both open and closed porosities of a natural LCF, for different diameter ranges, were assessed. Fibers extracted from the mesocarp of the coconut fruit were investigated by nondestructive methods of density measurements and x-ray microtomography (microCT). It was found that, for all diameter ranges, the closed porosity is significantly higher than the open porosity. The total porosity increases with diameter to around 60% for coir fibers with more than 503 μm in diameter. The amount and characteristics of these open and closed porosities were revealed by t test and Weibull statistics as well as by microCT.

  14. Eddy sensors for small diameter stainless steel tubes.

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, Jack L.; Morales, Alfredo Martin; Grant, J. Brian; Korellis, Henry James; LaFord, Marianne Elizabeth; Van Blarigan, Benjamin; Andersen, Lisa E.

    2011-08-01

    The goal of this project was to develop non-destructive, minimally disruptive eddy sensors to inspect small diameter stainless steel metal tubes. Modifications to Sandia's Emphasis/EIGER code allowed for the modeling of eddy current bobbin sensors near or around 1/8-inch outer diameter stainless steel tubing. Modeling results indicated that an eddy sensor based on a single axial coil could effectively detect changes in the inner diameter of a stainless steel tubing. Based on the modeling results, sensor coils capable of detecting small changes in the inner diameter of a stainless steel tube were designed, built and tested. The observed sensor response agreed with the results of the modeling and with eddy sensor theory. A separate limited distribution SAND report is being issued demonstrating the application of this sensor.

  15. Axon diameter mapping in crossing fibers with diffusion MRI

    DEFF Research Database (Denmark)

    Zhang, Hui; Dyrby, Tim B; Alexander, Daniel C

    2011-01-01

    This paper proposes a technique for a previously unaddressed problem, namely, mapping axon diameter in crossing fiber regions, using diffusion MRI. Direct measurement of tissue microstructure of this kind using diffusion MRI offers a new class of biomarkers that give more specific information about...... model to enable axon diameter mapping in voxels with crossing fibers. We show in simulation that the technique can provide robust axon diameter estimates in a two-fiber crossing with the crossing angle as small as 45 degrees. Using ex vivo imaging data, we further demonstrate the feasibility...... tissue than measures derived from diffusion tensor imaging. Most existing techniques for axon diameter mapping assume a single axon orientation in the tissue model, which limits their application to only the most coherently oriented brain white matter, such as the corpus callosum, where the single...

  16. Study of Linearly Polarized Light Measuring Fiber Diameter

    Energy Technology Data Exchange (ETDEWEB)

    Liang Hong, E-mail: lianghong@cuc.edu.cn [School of science, Communication University of China 100024 (China)

    2011-02-01

    The letter discusses a new way to measure fiber diameters, studies the theory of measuring fiber radius using this way, carries out numerical simulation based on this and provides experiment method as well.

  17. Synthesis of very small diameter silica nanofibers using sound waves.

    Science.gov (United States)

    Datskos, Panos; Chen, Jihua; Sharma, Jaswinder

    2014-07-14

    Silica nanofibers of an average diameter ≈30 nm and length ≈100 μm have been synthesized using an unprecedented strategy: sound waves. A new phenomenon, spinning off the nanofibers at silica rod tips, is also observed.

  18. Observations on placentome diameters in gestating West African ...

    African Journals Online (AJOL)

    ADEYEYE

    2015-09-09

    com. Abstract. This study investigated the effect of experimental Trypanosoma brucei infection on the placentome diameter (PD) of twenty four gestating West African dwarf does. The does were randomized into 4 equal groups ...

  19. Diameter constrained reliability of ladders and Spanish fans

    Directory of Open Access Journals (Sweden)

    Cancela Héctor

    2016-01-01

    Full Text Available We are given a graph G = (V, E, terminal set K  V and diameter d > 0. Links fail stochastically and independently with known probabilities. The diameter-constrained reliability (DCR for short, is the probability that the K-diameter is not greater than d in the subgraph induced by non-failed links. The contributions of this paper are two-fold. First, the computational complexity of DCR-subproblems is discussed in terms of the number of terminals k = jKj and diameter d. Here, we prove that when d > 2 the problem is NP-Hard when K = V. Second, we compute the DCR efficiently for Ladders and Spanish Fans. Open problems and trends for future work are discussed in the conclusions.

  20. Improved Design Basis for Laterally Loaded Large Diameter Pile

    DEFF Research Database (Denmark)

    Leth, Caspar Thrane

    with a capacity of 3.6 MW and placed at water depths beyond 25 m. Different foundation solutions have over the years been applied for offshore turbines, but monopiles are currently the most applied foundation type and are typically with a pile diameter of 4-6 m and applied up to a water depth of 25 m...... on the structure and the productivity of the turbine. Current design practice for monopiles are based on p-y curves developed for slender piles with a diameter of 0.6 m. The focus on the structure stiffness has entailed a significant research on the soil-structure interaction for large diameter monopiles....... Comparison of the different approaches shows some discrepancy and conflicting statements, but the main findings can be summarized as: • The standard p-y curves are inadequate to describe the behaviour of lateral loaded large diameter rigid piles. • Initial stiffness of the p-y curves is depended...

  1. Retinoid Uptake, Processing, and Secretion in Human iPS-RPE Support the Visual Cycle

    Science.gov (United States)

    Muñiz, Alberto; Greene, Whitney A.; Plamper, Mark L.; Choi, Jae Hyek; Johnson, Anthony J.; Tsin, Andrew T.; Wang, Heuy-Ching

    2014-01-01

    Purpose. Retinal pigmented epithelium derived from human induced pluripotent stem (iPS) cells (iPS-RPE) may be a source of cells for transplantation. For this reason, it is essential to determine the functional competence of iPS-RPE. One key role of the RPE is uptake and processing of retinoids via the visual cycle. The purpose of this study is to investigate the expression of visual cycle proteins and the functional ability of the visual cycle in iPS-RPE. Methods. iPS-RPE was derived from human iPS cells. Immunocytochemistry, RT-PCR, and Western blot analysis were used to detect expression of RPE genes lecithin-retinol acyl transferase (LRAT), RPE65, cellular retinaldehyde-binding protein (CRALBP), and pigment epithelium–derived factor (PEDF). All-trans retinol was delivered to cultured cells or whole cell homogenate to assess the ability of the iPS-RPE to process retinoids. Results. Cultured iPS-RPE expresses visual cycle genes LRAT, CRALBP, and RPE65. After incubation with all-trans retinol, iPS-RPE synthesized up to 2942 ± 551 pmol/mg protein all-trans retinyl esters. Inhibition of LRAT with N-ethylmaleimide (NEM) prevented retinyl ester synthesis. Significantly, after incubation with all-trans retinol, iPS-RPE released 188 ± 88 pmol/mg protein 11-cis retinaldehyde into the culture media. Conclusions. iPS-RPE develops classic RPE characteristics and maintains expression of visual cycle proteins. The results of this study confirm that iPS-RPE possesses the machinery to process retinoids for support of visual pigment regeneration. Inhibition of all-trans retinyl ester accumulation by NEM confirms LRAT is active in iPS-RPE. Finally, the detection of 11-cis retinaldehyde in the culture medium demonstrates the cells' ability to process retinoids through the visual cycle. This study demonstrates expression of key visual cycle machinery and complete visual cycle activity in iPS-RPE. PMID:24255038

  2. Retinoid uptake, processing, and secretion in human iPS-RPE support the visual cycle.

    Science.gov (United States)

    Muñiz, Alberto; Greene, Whitney A; Plamper, Mark L; Choi, Jae Hyek; Johnson, Anthony J; Tsin, Andrew T; Wang, Heuy-Ching

    2014-01-09

    Retinal pigmented epithelium derived from human induced pluripotent stem (iPS) cells (iPS-RPE) may be a source of cells for transplantation. For this reason, it is essential to determine the functional competence of iPS-RPE. One key role of the RPE is uptake and processing of retinoids via the visual cycle. The purpose of this study is to investigate the expression of visual cycle proteins and the functional ability of the visual cycle in iPS-RPE. iPS-RPE was derived from human iPS cells. Immunocytochemistry, RT-PCR, and Western blot analysis were used to detect expression of RPE genes lecithin-retinol acyl transferase (LRAT), RPE65, cellular retinaldehyde-binding protein (CRALBP), and pigment epithelium-derived factor (PEDF). All-trans retinol was delivered to cultured cells or whole cell homogenate to assess the ability of the iPS-RPE to process retinoids. Cultured iPS-RPE expresses visual cycle genes LRAT, CRALBP, and RPE65. After incubation with all-trans retinol, iPS-RPE synthesized up to 2942 ± 551 pmol/mg protein all-trans retinyl esters. Inhibition of LRAT with N-ethylmaleimide (NEM) prevented retinyl ester synthesis. Significantly, after incubation with all-trans retinol, iPS-RPE released 188 ± 88 pmol/mg protein 11-cis retinaldehyde into the culture media. iPS-RPE develops classic RPE characteristics and maintains expression of visual cycle proteins. The results of this study confirm that iPS-RPE possesses the machinery to process retinoids for support of visual pigment regeneration. Inhibition of all-trans retinyl ester accumulation by NEM confirms LRAT is active in iPS-RPE. Finally, the detection of 11-cis retinaldehyde in the culture medium demonstrates the cells' ability to process retinoids through the visual cycle. This study demonstrates expression of key visual cycle machinery and complete visual cycle activity in iPS-RPE.

  3. X-Ray and electron beam source characterization from Self-Modulated Laser Wakefield Acceleration experiments at Titan

    Science.gov (United States)

    King, Paul; Lemos, Nuno; Albert, Felicie; Shaw, Jessica; Milder, Avi; Marsh, Ken; Pak, Art; Hegelich, Bjorn; Joshi, Chan

    2017-10-01

    The development of a directional, low-divergence, and short-duration (ps and sub-ps) x-ray probes with energies of tens of keV is desirable for the fields of astrophysics, High Energy Density Science and Inertial Confinement Fusion. In this work we focused the Titan laser beam (1 ps and 150 Joules) into a 4mm helium gas jet to produce an electron beam that in turn generates an x-ray beam. The measured Raman Forward Scattering satellites present in the laser spectrum after the interaction, indicate the generation of a Self-modulated laser wakefield accelerator. This accelerator produced an electron beam with energies up to 250 MeV, a divergence of 16 x 40 mrad and a total charge of 6 nC. Using this high-charge relativistic electron beam we explored the combination of three mechanisms to produce an x-ray beam: Betatron, Compton scattering and Bremsstrahlung. We show the generation of a low divergence (mrad), small source size (um) broadband (keV to MeV) x-ray beam that can be used as a backlighter for time-resolved spectroscopy, imaging, and Compton radiography. Work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344. [LLNL-ABS-734746].

  4. A Multi-Turn Measurement System for the CERN PS

    CERN Document Server

    Angoletta, Maria Elena

    2002-01-01

    Multi-turn beam position measurements on one or more pickups provide very important information needed to derive machine optics parameters. A variety of analyses is possible, such as determination of phase advance, detuning with amplitude, and most important, the exploration of phase space. In this paper we present a new multi-turn acquisition system for the CERN Proton Synchrotron based on a CompactPCI fast digitiser and a new general object-oriented visualisation and analysis tool for the acquired multi-turn data.

  5. Low current beam techniques

    Energy Technology Data Exchange (ETDEWEB)

    Saint, A.; Laird, J.S.; Bardos, R.A.; Legge, G.J.F. [Melbourne Univ., Parkville, VIC (Australia). School of Physics; Nishijima, T.; Sekiguchi, H. [Electrotechnical Laboratory, Tsukuba (Japan).

    1993-12-31

    Since the development of Scanning Transmission Microscopy (STIM) imaging in 1983 many low current beam techniques have been developed for the scanning (ion) microprobe. These include STIM tomography, Ion Beam Induced Current, Ion Beam Micromachining and Microlithography and Ionoluminense. Most of these techniques utilise beam currents of 10{sup -15} A down to single ions controlled by beam switching techniques This paper will discuss some of the low beam current techniques mentioned above, and indicate, some of their recent applications at MARC. A new STIM technique will be introduced that can be used to obtain Z-contrast with STIM resolution. 4 refs., 3 figs.

  6. Predicting fir trees stem diameters using Artificial Neural Network ...

    African Journals Online (AJOL)

    The aim of this paper is to examine the applicability of Artificial Neural Network models (ANNs), in the prediction of fir trees stem over bark diameters at 5.3, 9.3, 13.3, 17.3, 21.3, 25.3, 29.3 and 33.3 meters above ground. The values of these diameters are necessary for an efficient estimation of a single tree volume using the ...

  7. Inhibition of Ps Formation in Benzene and Cyclohexane by CH3CI and CH3Br

    DEFF Research Database (Denmark)

    Wikander, G.; Mogensen, O. E.; Pedersen, Niels Jørgen

    1983-01-01

    Positron-annihilation lifetime spectra have been measured for mixtures of CH3Cl and CH3Br in cyclohexane and of CH3Cl in benzene. The ortho-positronium (Ps) yield decreased monotonically from 38% and 43% in cyclohexane and benzene respectively to 11% in pure CH3Cl and 6% in pure CH3Br. The strength......− anions to form Ps. while it forms a bound state with the halides. X−. CH3Cl was a roughly three times weaker Ps inhibitor in benzene than in cyclohexane, which shows that CH3Cl− does not dechlorinate in times comparable to or shorter than 400–500 ps in benzene. An improved model for the explanation of Ps...

  8. Chemical resistance of core-shell particles (PS/PMMA polymerized by seeded suspension

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Belchior Ribeiro

    2017-09-01

    Full Text Available Abstract Core-shell particles were produced on seeded suspension polymerization by using polystyrene (PS as polymer core, or seed, and methyl methacrylate (MMA as the shell forming monomer. Two synthesis routes were evaluated by varying the PS seed conversion before MMA addition. The main purpose of this work was to investigate the influence of synthesis routes on the morphology and chemical resistance of the resulting particles. 1H NMR spectroscopy showed that the use of PS seeds with lower conversion led to the formation of higher amount of poly(styrene-co-MMA. The copolymer acted as a compatibilizer, decreasing the interfacial energy between both homopolymers. As a consequence, a larger amount of reduced PMMA cluster were formed, as was revealed by TEM measurements. Samples in this system showed enhanced resistance to cyclohexane attack compared with pure PS, with a PS extraction of only 37% after 54 hours test.

  9. iPS cell technologies: significance and applications to CNS regeneration and disease

    Science.gov (United States)

    2014-01-01

    In 2006, we demonstrated that mature somatic cells can be reprogrammed to a pluripotent state by gene transfer, generating induced pluripotent stem (iPS) cells. Since that time, there has been an enormous increase in interest regarding the application of iPS cell technologies to medical science, in particular for regenerative medicine and human disease modeling. In this review article, we outline the current status of applications of iPS technology to cell therapies (particularly for spinal cord injury), as well as neurological disease-specific iPS cell research (particularly for Parkinson’s disease and Alzheimer’s disease). Finally, future directions of iPS cell research are discussed including a) development of an accurate assay system for disease-associated phenotypes, b) demonstration of causative relationships between genotypes and phenotypes by genome editing, c) application to sporadic and common diseases, and d) application to preemptive medicine. PMID:24685317

  10. Tribology and Microstructure of PS212 with a Cr2O3 Seal Coat

    Science.gov (United States)

    Sliney, Harold E.; Benoy, Patricia A.; Korenyi-Both, Andras; Dellacorte, Christopher

    1994-01-01

    PS212 is a plasma sprayed metal bonding chrome carbide coating with solid lubricant additives which has lubricating properties at temperatures up to about 900 deg C. The coating is diamond ground to achieve an acceptable tribological surface. But, as with many plasma spray coatings, PS212 is not fully-dense. In this study, a chromium oxide base seal coating is used in an attempt to seal any porosity that is open to the surface of the PS212 coating, and to study the effect of the sealant on the tribological properties of PS212. The results indicate that the seal coating reduces friction and wear when it is applied and then diamond ground leaving a thin layer of seal coating which fills in the surface pits of the PS212 coating.

  11. Perbandingan Unjuk Kerja Kompor Methanol dengan Variasi Diameter Burner

    Directory of Open Access Journals (Sweden)

    Subroto Subroto

    2016-08-01

    Full Text Available Sampai saat ini sebagian masyarakat masih anyak menggunakan minyak tanah sebagai bahan bakar untuk keperluan rumah tangga maupun industri, walaupun harga minyak tanah naik cukup tinggi karena subsidi dari pemerintah dicabut. Untuk mengurangi ketergantungan minyak tanah perlu penggunaan bahan bakar alternatif yaitu methanol. Methanol mempunyai kelebihan mudah didapatkan di lapangan dan dengan harga yang lebih murah dari minyak tanah. Kompor methanol sudah dikenal masyarakat akan tetapi penggunaannya masih sangat terbatas karena unjuk kerjanya masih kurang baik dibandingkan kompor minyak tanah. Penelitian ini bertujuan untuk mengetahui unjuk kerja kompor methanol melalui pengaruh variasi diameter burner.               Penelitian dimulai dengan rancang bangun burner terbuat dari bahan kuningan dengan tiga macam model dengan variasi diameter burner dan tinggi burner maupun jumlah lubang tetap. Pengujian unjuk kerja berdasarkan karakteristik pembakaran dilakukan melalui water boiling test. Parameter yang diukur meliputi temperatur api pembakaran, temperatur air, konsumsi bahan bakar, dan waktu pendidihan.               Hasil penelitian menunjukkan bahwa variasi diameter burner berpengaruh terhadap karakteristik pembakaran yang dihasilkan. Temperatur pembakaran yang tinggi dicapai oleh burner dengan diameter 12,8mm dan 10mm, konsumsi bahan bakar yang kecil burner diameter 12,8mm dan waktu pendidihan yang pendek dicapai burner 12,8mm. Jadi kompor methanol dengan unjuk kerja terbaik adalah kompor methanol dengan diameter burner 12,8mm.

  12. Catalytic growth of carbon nanotubes with large inner diameters

    Directory of Open Access Journals (Sweden)

    WEI REN ZHONG

    2005-02-01

    Full Text Available Carbon nanotubes (2.4 g/g catalyst, with large inner diameters were successfully synthesized through pyrolysis of methane on a Ni–Cu–Al catalyst by adding sodium carbonate into the carbon nanotubes growth system. The inner diameter of the carbon nanotubes prepared by this method is about 20–60 nm, while their outer diameter is about 40–80 nm. Transmission electron microscopy and X-ray diffraction were employed to investigate the morphology and microstructures of the carbon nanotubes. The analyses showed that these carbon nanotubes have large inner diameters and good graphitization. The addition of sodium carbonate into the reaction system brings about a slight decrease in the methane conversion and the yield of carbon. The experimental results showed that sodium carbonate is a mildly toxic material which influenced the catalytic activity of the Ni–Cu–Al catalyst and resulted in the formation of carbon nanotubes with large inner diameters. The growth mechanism of the carbon nanotubes with large inner diameters is discussed in this paper.

  13. Beam lines from Linac 1 and Linac 2 to the Booster

    CERN Multimedia

    CERN PhotoLab

    1978-01-01

    View against the direction of the beams. Both Linacs are behind the concrete wall at the back of the picture. The 50 MeV proton beam from Linac 1 enters the PS tunnel through the hole at left. The line from Linac 2, in the process of being installed, comes from the hole at right. The lines converge at a switching magnet (prominently in the foreground), which selects which of the 2 beams to send on to the Booster. See also 7802261 and further explanations there.

  14. Atomic scattering from an adsorbed monolayer solid with a helium beam that penetrates to the substrate

    DEFF Research Database (Denmark)

    Hansen, Flemming Yssing; Bruch, L.W.; Dammann, Bernd

    2013-01-01

    Diffraction and one-phonon inelastic scattering of a thermal energy helium atomic beam are evaluated in the situation that the target monolayer lattice is so dilated that the atomic beam penetrates to the interlayer region between the monolayer and the substrate. The scattering is simulated......(1 × 1) commensurate monolayer solid of H2/KCl(001). For the latter, there are cases where part of the incident beam is trapped in the interlayer region for times exceeding 50 ps, depending on the spacing between the monolayer and the substrate and on the angle of incidence. The feedback effect...

  15. Beam Instabilities studies at transition crossing in the CERN Proton Synchrotron

    CERN Document Server

    Aumon, S; Bartmann, W; Gilardoni, S; Métral, E; Rumolo, G; Steerenberg, R

    2010-01-01

    The CERN PS crosses transition energy at about 6 GeV by using a second order gamma jump performed with special quadrupoles. However, for high-intensity beams, and in particular the single bunch beam for the neutron Time-of-Flight facility, a controlled longitudinal emittance blowup is still needed to prevent a fast single-bunch vertical instability from developing near transition. A series of studies have been done in the PS in 2008 to measure the beam behaviour near transition energy for different settings of the gamma transition jump. The purpose of this paper is to compare those measurements with simulations results from the HEADTAIL code, which should allow to understand better the different mechanisms involved and maybe improve the transition crossing.

  16. Intron-exon organization of the active human protein S gene PS. alpha. and its pseudogene PS. beta. : Duplication and silencing during primate evolution

    Energy Technology Data Exchange (ETDEWEB)

    Ploos van Amstel, H.; Reitsma, P.H.; van der Logt, C.P.; Bertina, R.M. (University Hospital, Leiden (Netherlands))

    1990-08-28

    The human protein S locus on chromosome 3 consists of two protein S genes, PS{alpha} and PS{beta}. Here the authors report the cloning and characterization of both genes. Fifteen exons of the PS{alpha} gene were identified that together code for protein S mRNA as derived from the reported protein S cDNAs. Analysis by primer extension of liver protein S mRNA, however, reveals the presence of two mRNA forms that differ in the length of their 5{prime}-noncoding region. Both transcripts contain a 5{prime}-noncoding region longer than found in the protein S cDNAs. The two products may arise from alternative splicing of an additional intron in this region or from the usage of two start sites for transcription. The intron-exon organization of the PS{alpha} gene fully supports the hypothesis that the protein S gene is the product of an evolutional assembling process in which gene modules coding for structural/functional protein units also found in other coagulation proteins have been put upstream of the ancestral gene of a steroid hormone binding protein. The PS{beta} gene is identified as a pseudogene. It contains a large variety of detrimental aberrations, viz., the absence of exon I, a splice site mutation, three stop codons, and a frame shift mutation. Overall the two genes PS{alpha} and PS{beta} show between their exonic sequences 96.5% homology. Southern analysis of primate DNA showed that the duplication of the ancestral protein S gene has occurred after the branching of the orangutan from the African apes. A nonsense mutation that is present in the pseudogene of man also could be identified in one of the two protein S genes of both chimpanzee and gorilla. This implicates that silencing of one of the two protein S genes must have taken place before the divergence of the three African apes.

  17. Effect of Exfoliated Graphene Nanoplatelets on Rheological, Morphological, Mechanical and Thermal Properties of Immiscible Polypropylene/Polystyrene (PP/PS Blends

    Directory of Open Access Journals (Sweden)

    Fatemeh Abbasi

    2016-11-01

    Full Text Available Polyolefin/polystyrene blends, prepared by mechanical mixing, were immiscible blends having two-phase structure with weak interface. An improvement in compatibility of PP and PS led to their enhanced blend properties and applications. The aim of this study was to investigate the effect of exfoliated graphene nanoplatelets (xGnP on the compatibility of PP/PS (80:20 blend by their rheological and mechanical behaviors. Samples of the blends were prepared using an internal mixer through simultaneous feeding of the components into the mixing chamber. The properties of blends were evaluated by rheometry, scanning electron microscopy (SEM, thermal gravimetric analysis (TGA, differential scanning calorimetry (DSC and mechanical tests. Rheological results showed that addition of xGnP, led to an increase in storage modulus and complex viscosity, especially at low frequencies, probably due to the confinement of polymer chain motions. SEM observations on the morphology of blends revealed that increasing the xGnP content obviously reduced the domain diameter of the dispersed PS phase, indicating a good compatibilizing effect for xGnP. The addition of xGnP into the PP/PS blend increased the tensile modulus and decreased the elongation-at-break, resulting from the rigidity and intrinsic mechanical characteristics of the grapheme nanoplatelets. Crystallinity of the samples also increased with higher xGnP content, which could be assigned to the nucleating effect of graphene platelets. Moreover, thermal stability of the blends were improved by increasing the xGnP level because xGnP as an efficient compatibilizing agent with high thermal conductivity provided a more uniform heat distribution profile.

  18. The synthesis of large-diameter ZnTe crystal for THz emitting and detection

    Science.gov (United States)

    Liu, Hang; Bai, Wei; Feng, Jiatai; Jie, Wanqi

    2017-10-01

    A high-quality, large-size ZnTe ingot with the diameter of 60 mm and the length of 80 mm were prepared by the modified temperature gradient solvent method, where the Te rich solution acted as both solubility promoter and reactant. Using this method, the crystallization temperature was reduced from 1568 K to 1333 K, plus, the crystal defects could be reduced in some extent due to the lower zinc partial pressure. Few Te inclusions are found in the as-grown ZnTe crystal with the bulk factor less than 0.1%. X-ray diffraction (XRD), infrared transmission microscope, fourier transform infrared (FT-IR) spectrometer, ultraviolet-visible (UV-Vis) spectrophotometer were used to analyze the qualities and properties of the ZnTe crystals. The infrared transmittance over the wavenumber range from 500 to 4000 cm-1 is about 60% and the band gap is about 2.23 eV at the room temperature. The FWHM of the detection pulse with the THz time-domain spectroscopy (THz-TDS) is about 0.34 ps. Besides, both the radiation and detection pulse have a wide frequency distribution about 3 THz at the room temperature. These results strongly indicate that the high-quality ZnTe crystal synthesized by the temperature gradient solvent method is superior for THz device applications.

  19. Electron beam welding and beam positioning

    OpenAIRE

    MOROZOV M.Y.; BRAVERMAN V.Y.; MEDNIKOV D.M.

    2015-01-01

    Programs for control of mutual movements of the welded parts and EB gun are written in the unified language ISO-7bit. Beam settings control uses electronic charts or optional languages, sometimes self-designed. Operator coordinates movements and beam settings manually.

  20. T10 Beam Studies & Beam Simulation

    CERN Document Server

    Bergmann, Michael Georges; Van Dijk, Maarten; CERN. Geneva. EN Department

    2017-01-01

    In order to test detector components before their installation in actual experiments, one uses test beams in which one can control particle typ, momentum and size to high degree. For this project the focus of a secondary beam at T10 in the East Area at CERN was analysed using an AZALEA telescope from DESY.