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Sample records for mcp electron multiplier

  1. Ceramic Electron Multiplier

    International Nuclear Information System (INIS)

    Comby, G.

    1996-01-01

    The Ceramic Electron Multipliers (CEM) is a compact, robust, linear and fast multi-channel electron multiplier. The Multi Layer Ceramic Technique (MLCT) allows to build metallic dynodes inside a compact ceramic block. The activation of the metallic dynodes enhances their secondary electron emission (SEE). The CEM can be used in multi-channel photomultipliers, multi-channel light intensifiers, ion detection, spectroscopy, analysis of time of flight events, particle detection or Cherenkov imaging detectors. (auth)

  2. Channel electron multipliers

    International Nuclear Information System (INIS)

    Seidman, A.; Avrahami, Z.; Sheinfux, B.; Grinberg, J.

    1976-01-01

    A channel electron multiplier is described having a tubular wall coated with a secondary-electron emitting material and including an electric field for accelerating the electrons, the electric field comprising a plurality of low-resistive conductive rings each alternating with a high-resistive insulating ring. The thickness of the low-resistive rings is many times larger than that of the high-resistive rings, being in the order of tens of microns for the low-resistive rings and at least one order of magnitude lower for the high-resistive rings; and the diameter of the channel tubular walls is also many times larger than the thickness of the high-resistive rings. Both single-channel and multiple-channel electron multipliers are described. A very important advantage, particularly in making multiple-channel multipliers, is the simplicity of the procedure that may be used in constructing such multipliers. Other operational advantages are described

  3. Microchannel electron multiplier

    International Nuclear Information System (INIS)

    Beranek, I.; Janousek, L.; Vitovsky, O.

    1981-01-01

    A microchannel electron multiplier is described for detecting low levels of alpha, beta, soft X-ray and UV radiations. It consists of a glass tube or a system of tubes of various shapes made of common technological glass. The inner tube surface is provided with an active coat with photoemitter and secondary emitter properties. (B.S.)

  4. Single electron counting using a dual MCP assembly

    International Nuclear Information System (INIS)

    Yang, Yuzhen; Liu, Shulin; Zhao, Tianchi; Yan, Baojun; Wang, Peiliang; Yu, Yang; Lei, Xiangcui; Yang, Luping; Wen, Kaile; Qi, Ming

    2016-01-01

    The gain, pulse height resolution and peak-to-valley ratio of single electrons detected by using a Chevron configured Microchannel Plate (MCP) assembly are studied. The two MCPs are separated by a 280 µm gap and are biased by four electrodes. The purpose of the study is to determine the optimum bias voltage arrangements for single electron counting. By comparing the results of various bias voltage combinations, we conclude that good performance for the electron counting can be achieved by operating the MCP assembly in saturation mode. In addition, by applying a small reverse bias voltage across the gap while adjusting the bias voltages of the MCPs, optimum performance of electron counting can be obtained. - Highlights: • Dual MCPs assembly with four electrodes using different voltage combinations has been investigated for single electron counting. • Both the MCP voltages and the gap voltage can affect the gain, pulse height resolution and P/V ratio. • A high gain of the first stage MCP, a saturation mode of the second stage MCP and an appropriately reverse gap voltage can improve the resolution greatly. • The optimum voltage arrangements is significant for the design of MCP detectors in single electron counting applications.

  5. GEM the gas electron multiplier

    CERN Document Server

    Sauli, Fabio

    1997-01-01

    We describe the basic structure and operation of a new device, the Gas Electron Multiplier. Consisting in a polymer foil, metal-clad on both sides and perforated by a high density of holes, the GEM mesh allows to pre-amplify charges released in the gas with good uniformity and energy. Coupled to a micro-strip plate, the pre-amplification element allows to preserve high rate capability and resolution at considerably lower operating voltages, thus completely eliminating discharges and instabilities. Several GEM grids can be operated in cascade; charge gains are large enough to allow detection of signals in the ionization mode on the last element, permitting the use of a simple printed circuit as read-out electrode. Two-dimensional read-out can then be easily implemented. A new generation of simple, reliable and cheap fast position sensitive detectors seems at hand.

  6. Spin sensitivity of a channel electron multiplier

    International Nuclear Information System (INIS)

    Scholten, R.E.; McClelland, J.J.; Kelley, M.H.; Celotta, R.J.

    1988-01-01

    We report direct measurements of the sensitivity of a channel electron multiplier to electrons with different spin orientations. Four regions of the multiplier cone were examined using polarized electrons at 100-eV incident energy. Pulse counting and analog modes of operation were both investigated and in each case the observed spin effects were less than 0.5%

  7. The gas electron multiplier (GEM)

    CERN Document Server

    Bouclier, Roger; Dominik, Wojciech; Hoch, M; Labbé, J C; Million, Gilbert; Ropelewski, Leszek; Sauli, Fabio; Sharma, A

    1996-01-01

    We describe operating priciples and results obtained with a new detector component: the Gas Electrons Multiplier (GEM). Consisting of a thin composite sheet with two metal layers separated by a thin insulator, and pierced by a regular matrix of open channels, the GEM electrode, inserted on the path of electrons in a gas detector, allows to transfer the charge with an amplification factor approaching ten. Uniform response and high rate capability are demonstrated. Coupled to another device, multiwire or micro-strip chamber, the GEM electrode permit to obtain higher gains or less critical operation; separation of the sensitive (conversion) volume and the detection volume has other advantages, as a built-in delay (useful for triggering purposes) and the possibility of applying high fields on the photo-cathode of ring imaging detectors to improve efficiency. Multiple GEM grids in the same gas volume allow to obtain large amplification factors in a succession of steps, leading to the realization of an effective ga...

  8. Gaseous Electron Multiplier (GEM) Detectors

    Science.gov (United States)

    Gnanvo, Kondo

    2017-09-01

    Gaseous detectors have played a pivotal role as tracking devices in the field of particle physics experiments for the last fifty years. Recent advances in photolithography and micro processing techniques have enabled the transition from Multi Wire Proportional Chambers (MWPCs) and Drift Chambers to a new family of gaseous detectors refer to as Micro Pattern Gaseous Detectors (MPGDs). MPGDs combine the basic gas amplification principle with micro-structure printed circuits to provide detectors with excellent spatial and time resolution, high rate capability, low material budget and high radiation tolerance. Gas Electron Multiplier (GEMs) is a well-established MPGD technology invented by F. Sauli at CERN in 1997 and deployed various high energy physics (HEP) and nuclear NP experiment for tracking systems of current and future NP experiments. GEM detector combines an exceptional high rate capability (1 MHz / mm2) and robustness against harsh radiation environment with excellent position and timing resolution performances. Recent breakthroughs over the past decade have allowed the possibility for large area GEMs, making them cost effective and high-performance detector candidates to play pivotal role in current and future particle physics experiments. After a brief introduction of the basic principle of GEM technology, I will give a brief overview of the GEM detectors used in particle physics experiments over the past decades and especially in the NP community at Thomas Jefferson National Laboratory (JLab) and Brookhaven National Laboratory (BNL). I will follow by a review of state of the art of the new GEM development for the next generation of colliders such as Electron Ion Collider (EIC) or High Luminosity LHC and future Nuclear Physics experiments. I will conclude with a presentation of the CERN-based RD51 collaboration established in 2008 and its major achievements regarding technological developments and applications of MPGDs.

  9. Electron cyclotron resonance multiply charged ion sources

    International Nuclear Information System (INIS)

    Geller, R.

    1975-01-01

    Three ion sources, that deliver multiply charged ion beams are described. All of them are E.C.R. ion sources and are characterized by the fact that the electrons are emitted by the plasma itself and are accelerated to the adequate energy through electron cyclotron resonance (E.C.R.). They can work without interruption during several months in a quasi-continuous regime. (Duty cycle: [fr

  10. Evaporator line for special electron tubes, in particular electron multipliers

    International Nuclear Information System (INIS)

    Richter, M.

    1984-01-01

    The invention has been aimed at reducing the effort for preventing short circuits in achieving certain material-dependent effects e.g. secondary emission, by deposition through evaporation in the production of electron tubes, in particular electron multipliers

  11. Electronic de-multipliers; Demultiplicateurs electroniques

    Energy Technology Data Exchange (ETDEWEB)

    Ailloud, J

    1948-07-01

    The counting of a huge number of events, randomly or periodically distributed, requires the use of electronic counters which can work with a flow of up to 500000 events per second, while mechanical systems have a much lower resolution which leads to an important percentage of losses (non-counted events). Thus, hybrid systems are generally used which comprise an electronic part with fast counting capabilities but low recording capacities, and a mechanical part for the recording of the successive resets of the electronic part. This report describes the basic elementary circuits of these electronic counters (de-multipliers): dividers by 2 and 5 and flip-flop circuits using triode and pentode valves for the counting of events in the decimal system. (J.S.)

  12. Effects of tritium on electron multiplier performance

    International Nuclear Information System (INIS)

    Kerst, R.A.; Malinowski, M.E.

    1980-01-01

    In developing diagnostic instruments for fusion reactors, it is necessary to measure the effects of tritium contamination on channel electron multipliers (CEM). A CEM was exposed to T 2 pressures of up to 1.5 x 10 -1 Pa, with exposure quantities ranging up to 8800 Pa-s. The counting rate of the CEM is shown to consist of a prompt (Type I) signal caused by gas-phase tritium and a residual (Type II) signal, probably caused by near-surface tritium. The potential for using CEMs for observing the dynamics of tritium adsorption and absorption is discussed

  13. Single electron based binary multipliers with overflow detection ...

    African Journals Online (AJOL)

    electron based device. Multipliers with overflow detection based on serial and parallel prefix computation algorithm are elaborately discussed analytically and designed. The overflow detection circuits works in parallel with a simplified multiplier to ...

  14. Performance of gas electron multiplier (GEM) detector

    International Nuclear Information System (INIS)

    Han, S. H.; Moon, B. S.; Kim, Y. K.; Chung, C. E.; Kang, H. D.; Cho, H. S.

    2002-01-01

    We have investigated in detail the operating properties of Gas Electron Multiplier (GEM) detectors with a double conical and a cylindrical structure in a wide range of external fields and GEM voltages. With the double conical GEM, the gain gradually increased with time by 10%; whereas this surface charging was eliminated with the cylindrical GEM. Effective gains above 1000 were easily observed over a wide range of collection field strengths in a gas mixture of Ar/CO 2 (70/30). The transparency and electron collection efficiency were found to depend on the ratio of external field and the applied GEM voltage; the mutual influence of both drift and collection fields was found to be trivial

  15. Charge transfer in gas electron multipliers

    Energy Technology Data Exchange (ETDEWEB)

    Ottnad, Jonathan; Ball, Markus; Ketzer, Bernhard; Ratza, Viktor; Razzaghi, Cina [HISKP, Bonn University, Nussallee 14-16, D-53115 Bonn (Germany)

    2015-07-01

    In order to efficiently employ a Time Projection Chamber (TPC) at interaction rates higher than ∝1 kHz, as foreseen e.g. in the ALICE experiment (CERN) and at CB-ELSA (Bonn), a continuous operation and readout mode is required. A necessary prerequisite is to minimize the space charge coming from the amplification system and to maintain an excellent spatial and energy resolution. Unfortunately these two goals can be in conflict to each other. Gas Electron Multipliers (GEM) are one candidate to fulfill these requirements. It is necessary to understand the processes within the amplification structure to find optimal operation conditions. To do so, we measure the charge transfer processes in and between GEM foils with different geometries and field configurations, and use an analytical model to describe the results. This model can then be used to predict and optimize the performance. The talk gives the present status of the measurements and describes the model.

  16. Fabrication and measurement of gas electron multiplier

    International Nuclear Information System (INIS)

    Zhang Minglong; Xia Yiben; Wang Linjun; Gu Beibei; Wang Lin; Yang Ying

    2005-01-01

    Gas electron multiplier (GEM) with special performance has been widely used in the field of radiation detectors. In this work, GEM film was fabricated using a 50 μm -thick kapton film by the therma evaporation and laser masking drilling technique. GEM film has many uniformly arrayed holes with a diameter of 100 μm and a gap of 223 μm. It was then set up to a gas-flowing detector with an effective area of 3 x 3 cm 2 , 5.9 keV X-ray generated from a 55 Fe source was used to measure the pulse height distribution of GEM operating at various high voltage and gas proportion. The effect of high potential and gas proportion on the count rate and the energy resolution was discussed in detail. The results indicate that GEM has a very high ratio of signal to noise and better energy resolution of 18.2%. (authors)

  17. Electron optics design of an 8-in. spherical MCP-PMT

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ping, E-mail: chenping@opt.cn [Key Laboratory of Ultra-fast photoelectric Diagnostics Technology, Xi’an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences, Xi’an 710119 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, Shanxi (China); Tian, Jinshou [Key Laboratory of Ultra-fast photoelectric Diagnostics Technology, Xi’an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences, Xi’an 710119 (China); Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, Shanxi (China); Qian, Sen; Zhao, Tianchi [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Liu, Hulin; Wei, Yonglin; Sai, Xiaofeng; He, Jianping; Wang, Xing; Lu, Yu [Key Laboratory of Ultra-fast photoelectric Diagnostics Technology, Xi’an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences, Xi’an 710119 (China); Chen, Lin; Guo, Lehui; Pei, Chengquan; Hui, Dandan [Key Laboratory of Ultra-fast photoelectric Diagnostics Technology, Xi’an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences, Xi’an 710119 (China); University of Chinese Academy of Sciences, Beijing 100049 (China)

    2017-03-11

    This paper discusses the electron optical system of an 8-in. spherical MCP-PMT. The MCP assembly, the supporting pole and the supply voltages are carefully designed to optimize the photoelectron collection efficiency and the transit time spread. Coating the MCP nickel-chromium electrode with an additional high secondary emission material is employed to make a breakthrough on the collection efficiency. With the simulation software CST, the Finite Integration method and the Monte Carlo method are combined to evaluate the collection efficiency, the time properties and the Earth's magnetic field effects. Simulation results show that the photocathode active solid angle is over 3.5 πsr, the average collection efficiency can exceed 95% with the coated MCP and the mean transit time spread is 2.2 ns for a typical electric potential of 500 V applied between the photocathode and the MCP input facet. The prototype and the measured single photoelectron spectrum are also presented.

  18. Tritium-caused background currents in electron multipliers

    International Nuclear Information System (INIS)

    Malinowski, M.E.

    1979-05-01

    One channel electron multiplier (Galileo No. 4501) and one 14 stage Be/Cu multiplier (Dumont No. SPM3) were exposed to tritium pressures between approx. 10 -7 Torr to 10 -3 Torr in amounts from approx. 10 -5 Torr-s to 60 Torr-s and the β-decay caused currents in the multipliers measured. The background currents in both multipliers consisted of two components: (1) a high, reversible current which was proportional to the tritium exposure pressure; and (2) a lower, irreversible background current which increased with increasing cumulative tritium exposure. The β-decay caused currents in each multiplier increased the same way with exposure, suggesting the detected electrons arose from decaying tritium adsorbed on surfaced external to the multipliers

  19. Simulation of the electron collection efficiency of a PMT based on the MCP coated with high secondary yield material

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Lin, E-mail: chenlin@opt.cn [State Key Laboratory of Transient Optics and Photonics, Xi' an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi' an 710119 (China); Graduate School of Chinese Academy of Sciences (CAS), Beijing 100049 (China); Xi' an Jiaotong University, Xi' an 710049 (China); Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006 (China); Tian, Jinshou [State Key Laboratory of Transient Optics and Photonics, Xi' an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi' an 710119 (China); Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006 (China); Zhao, Tianchi [Institute of High Energy Physics (IHEP) of CAS, Beijing 100049 (China); Liu, Chunliang [Xi' an Jiaotong University, Xi' an 710049 (China); Liu, Hulin; Wei, Yonglin; Sai, Xiaofeng [State Key Laboratory of Transient Optics and Photonics, Xi' an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi' an 710119 (China); Chen, Ping [State Key Laboratory of Transient Optics and Photonics, Xi' an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi' an 710119 (China); Graduate School of Chinese Academy of Sciences (CAS), Beijing 100049 (China); Wang, Xing; Lu, Yu [State Key Laboratory of Transient Optics and Photonics, Xi' an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi' an 710119 (China); Hui, Dandan [State Key Laboratory of Transient Optics and Photonics, Xi' an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi' an 710119 (China); Graduate School of Chinese Academy of Sciences (CAS), Beijing 100049 (China)

    2016-11-01

    Owning to the serious loss of photoelectrons striking at the input electrode of traditional microchannel plate (MCP), photoelectron collection efficiency (CE) of photomultiplier tubes based on MCP (MCP-PMTs) fluctuates around the MCP open area fraction and cannot make a breakthrough. Depositing a thin film of high secondary electron yield material on the MCP is proposed as an effective approach to improve the CE. The available simulation and experimental data to validate it, however, is sparse. In our work, a three-dimensional small area MCP model is developed in CST Studio Suite to evaluate the collection efficiencies of PMTs based on the traditional MCP and the coated one, respectively. Results predict that CE of the PMT based on the coated MCP has a significant increase and a better uniformity, which is expected to reach 100%.

  20. Production processes of multiply charged ions by electron impact

    International Nuclear Information System (INIS)

    Oda, Nobuo

    1980-02-01

    First, are compared the foil or gas stripper and the ion sources utilizing electron-atom ionizing collisions, which are practically used or are under development to produce multiply charged ions. A review is made of the fundamental physical parameters such as successive ionization potentials and various ionization cross sections by electron impact, as well as the primary processes in multiply charged ion production. Multiply charged ion production processes are described for the different existing ion sources such as high temperature plasma type, ion-trapping type and discharge type. (author)

  1. Electronic de-multipliers II (ring-shape systems)

    International Nuclear Information System (INIS)

    Raievski, V.

    1948-09-01

    This report describes a new type of ring-shape fast electronic counter (de-multiplier) with a resolution capacity equivalent to the one made by Regener (Rev. of Scientific Instruments USA 1946, 17, 180-89) but requiring two-times less electronic valves. This report follows the general description of electronic de-multipliers made by J. Ailloud (CEA--001). The ring comprises 5 flip-flop circuits with two valves each. The different elements of the ring are calculated with enough details to allow the transfer of this calculation to different valve types. (J.S.)

  2. The Tynode: A new vacuum electron multiplier

    Energy Technology Data Exchange (ETDEWEB)

    Graaf, Harry van der, E-mail: vdgraaf@nikhef.nl [Delft University of Technology, Delft (Netherlands); Nikhef, Science Park 105, 1098 XG Amsterdam (Netherlands); Akhtar, Hassan; Budko, Neil; Chan, Hong Wah; Hagen, Cornelis W. [Delft University of Technology, Delft (Netherlands); Hansson, Conny C.T. [Delft University of Technology, Delft (Netherlands); Nikhef, Science Park 105, 1098 XG Amsterdam (Netherlands); Nützel, Gert; Pinto, Serge D. [Photonis, Roden (Netherlands); Prodanović, Violeta; Raftari, Behrouz; Sarro, Pasqualina M. [Delft University of Technology, Delft (Netherlands); Sinsheimer, John; Smedley, John [Brookhaven National Laboratory, Upton, NY 11973 (United States); Tao, Shuxia [Eindhoven University of Technology/DIFFER (Netherlands); Theulings, Anne M.M.G. [Delft University of Technology, Delft (Netherlands); Nikhef, Science Park 105, 1098 XG Amsterdam (Netherlands); Vuik, Kees [Delft University of Technology, Delft (Netherlands)

    2017-03-01

    By placing, in vacuum, a stack of transmission dynodes (tynodes) on top of a CMOS pixel chip, a single free electron detector could be made with outstanding performance in terms of spatial and time resolution. The essential object is the tynode: an ultra thin membrane, which emits, at the impact of an energetic electron on one side, a multiple of electrons at the other side. The electron yields of tynodes have been calculated by means of GEANT-4 Monte Carlo simulations, applying special low-energy extensions. The results are in line with another simulation based on a continuous charge-diffusion model. By means of Micro Electro Mechanical System (MEMS) technology, tynodes and test samples have been realized. The secondary electron yield of several samples has been measured in three different setups. Finally, several possibilities to improve the yield are presented.

  3. Multiply excited molecules produced by photon and electron interactions

    International Nuclear Information System (INIS)

    Odagiri, T.; Kouchi, N.

    2006-01-01

    The photon and electron interactions with molecules resulting in the formation of multiply excited molecules and the subsequent decay are subjects of great interest because the independent electron model and Born-Oppenheimer approximation are much less reliable for the multiply excited states of molecules than for the ground and lower excited electronic states. We have three methods to observe and investigate multiply excited molecules: 1) Measurements of the cross sections for the emission of fluorescence emitted by neutral fragments in the photoexcitation of molecules as a function of incident photon energy [1-3], 2) Measurements of the electron energy-loss spectra tagged with the fluorescence photons emitted by neutral fragments [4], 3) Measurements of the cross sections for generating a pair of photons in absorption of a single photon by a molecule as a function of incident photon energy [5-7]. Multiply excited states degenerate with ionization continua, which make a large contribution in the cross section curve involving ionization processes. The key point of our methods is hence that we measure cross sections free from ionization. The feature of multiply excited states is noticeable in such a cross section curve. Recently we have measured: i) the cross sections for the emission of the Lyman- fluorescence in the photoexcitation of CH 4 as a function of incident photon energy in the range 18-51 eV, ii) the electron energy-loss spectrum of CH 4 tagged with the Lyman-photons at 80 eV incident electron energy and 10 electron scattering angle in the range of the energy loss 20-45 eV, in order to understand the formation and decay of the doubly excited methane in photon and electron interactions. [8] The results are summarized in this paper and the simultaneous excitation of two electrons by electron interaction is compared with that by photon interaction in terms of the oscillator strength. (authors)

  4. Optimization of the electron collection efficiency of a large area MCP-PMT for the JUNO experiment

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Lin, E-mail: chenlin@opt.cn [State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi’an 710119 (China); Graduate School of Chinese Academy of Sciences (CAS), Beijing 100049 (China); Xi’an Jiaotong University, Xi’an 710049 (China); Tian, Jinshou [Graduate School of Chinese Academy of Sciences (CAS), Beijing 100049 (China); Liu, Chunliang [Xi’an Jiaotong University, Xi’an 710049 (China); Wang, Yifang; Zhao, Tianchi [Institute of High Energy Physics (IHEP) of CAS, Beijing 100049 (China); Liu, Hulin; Wei, Yonglin; Sai, Xiaofeng [Graduate School of Chinese Academy of Sciences (CAS), Beijing 100049 (China); Chen, Ping [State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi’an 710119 (China); Graduate School of Chinese Academy of Sciences (CAS), Beijing 100049 (China); Wang, Xing; Lu, Yu [Graduate School of Chinese Academy of Sciences (CAS), Beijing 100049 (China); Hui, Dandan; Guo, Lehui [State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi’an 710119 (China); Graduate School of Chinese Academy of Sciences (CAS), Beijing 100049 (China); Liu, Shulin; Qian, Sen; Xia, Jingkai; Yan, Baojun; Zhu, Na [Institute of High Energy Physics (IHEP) of CAS, Beijing 100049 (China); Sun, Jianning; Si, Shuguang [North Night Vision Technology (NNVT) CO., LTD, Nanjing 210110 (China); and others

    2016-08-11

    A novel large-area (20-inch) photomultiplier tube based on microchannel plate (MCP-PMTs) is proposed for the Jiangmen Underground Neutrino Observatory (JUNO) experiment. Its photoelectron collection efficiency C{sub e} is limited by the MCP open area fraction (A{sub open}). This efficiency is studied as a function of the angular (θ), energy (E) distributions of electrons in the input charge cloud and the potential difference (U) between the PMT photocathode and the MCP input surface, considering secondary electron emission from the MCP input electrode. In CST Studio Suite, Finite Integral Technique and Monte Carlo method are combined to investigate the dependence of C{sub e} on θ, E and U. Results predict that C{sub e} can exceed A{sub open}, and are applied to optimize the structure and operational parameters of the 20-inch MCP-PMT prototype. C{sub e} of the optimized MCP-PMT is expected to reach 81.2%. Finally, the reduction of the penetration depth of the MCP input electrode layer and the deposition of a high secondary electron yield material on the MCP are proposed to further optimize C{sub e}.

  5. Optimization of the electron collection efficiency of a large area MCP-PMT for the JUNO experiment

    International Nuclear Information System (INIS)

    Chen, Lin; Tian, Jinshou; Liu, Chunliang; Wang, Yifang; Zhao, Tianchi; Liu, Hulin; Wei, Yonglin; Sai, Xiaofeng; Chen, Ping; Wang, Xing; Lu, Yu; Hui, Dandan; Guo, Lehui; Liu, Shulin; Qian, Sen; Xia, Jingkai; Yan, Baojun; Zhu, Na; Sun, Jianning; Si, Shuguang

    2016-01-01

    A novel large-area (20-inch) photomultiplier tube based on microchannel plate (MCP-PMTs) is proposed for the Jiangmen Underground Neutrino Observatory (JUNO) experiment. Its photoelectron collection efficiency C e is limited by the MCP open area fraction (A open ). This efficiency is studied as a function of the angular (θ), energy (E) distributions of electrons in the input charge cloud and the potential difference (U) between the PMT photocathode and the MCP input surface, considering secondary electron emission from the MCP input electrode. In CST Studio Suite, Finite Integral Technique and Monte Carlo method are combined to investigate the dependence of C e on θ, E and U. Results predict that C e can exceed A open , and are applied to optimize the structure and operational parameters of the 20-inch MCP-PMT prototype. C e of the optimized MCP-PMT is expected to reach 81.2%. Finally, the reduction of the penetration depth of the MCP input electrode layer and the deposition of a high secondary electron yield material on the MCP are proposed to further optimize C e .

  6. The Gas Electron Multiplier Chamber Exhibition LEPFest 2000

    CERN Multimedia

    2000-01-01

    The Gas Electron Multiplier (GEM) is a novel device introduced in 1996.Large area detectors based on this technology are in construction for high energy physics detectors.This technology can also be used for high-rate X-ray imaging in medical diagnostics and for monitoring irradiation during cancer treatment

  7. Statistics of electron multiplication in multiplier phototube: iterative method

    International Nuclear Information System (INIS)

    Grau Malonda, A.; Ortiz Sanchez, J.F.

    1985-01-01

    An iterative method is applied to study the variation of dynode response in the multiplier phototube. Three different situations are considered that correspond to the following ways of electronic incidence on the first dynode: incidence of exactly one electron, incidence of exactly r electrons and incidence of an average anti-r electrons. The responses are given for a number of steps between 1 and 5, and for values of the multiplication factor of 2.1, 2.5, 3 and 5. We study also the variance, the skewness and the excess of jurtosis for different multiplication factors. (author)

  8. Statistics of electron multiplication in a multiplier phototube; Iterative method

    International Nuclear Information System (INIS)

    Ortiz, J. F.; Grau, A.

    1985-01-01

    In the present paper an iterative method is applied to study the variation of dynode response in the multiplier phototube. Three different situation are considered that correspond to the following ways of electronic incidence on the first dynode: incidence of exactly one electron, incidence of exactly r electrons and incidence of an average r electrons. The responses are given for a number of steps between 1 and 5, and for values of the multiplication factor of 2.1, 2.5, 3 and 5. We study also the variance, the skewness and the excess of jurtosis for different multiplication factors. (Author) 11 refs

  9. Charge amplification and transfer processes in the gas electron multiplier

    International Nuclear Information System (INIS)

    Bachmann, S.; Bressan, A.; Ropelewski, L.; Sauli, F.; Sharma, A.; Moermann, D.

    1999-01-01

    We report the results of systematic investigations on the operating properties of detectors based on the gas electron multiplier (GEM). The dependence of gain and charge collection efficiency on the external fields has been studied in a range of values for the hole diameter and pitch. The collection efficiency of ionization electrons into the multiplier, after an initial increase, reaches a plateau extending to higher values of drift field the larger the GEM voltage and its optical transparency. The effective gain, fraction of electrons collected by an electrode following the multiplier, increases almost linearly with the collection field, until entering a steeper parallel plate multiplication regime. The maximum effective gain attainable increases with the reduction in the hole diameter, stabilizing to a constant value at a diameter approximately corresponding to the foil thickness. Charge transfer properties appear to depend only on ratios of fields outside and within the channels, with no interaction between the external fields. With proper design, GEM detectors can be optimized to satisfy a wide range of experimental requirements: tracking of minimum ionizing particles, good electron collection with small distortions in high magnetic fields, improved multi-track resolution and strong ion feedback suppression in large volume and time-projection chambers

  10. Charge-transfer properties in the gas electron multiplier

    International Nuclear Information System (INIS)

    Han, Sanghyo; Kim, Yongkyun; Cho, Hyosung

    2004-01-01

    The charge transfer properties of a gas electron multiplier (GEM) were systematically investigated over a broad range of electric field configurations. The electron collection efficiency and the charge sharing were found to depend on the external fields, as well as on the GEM voltage. The electron collection efficiency increased with the collection field up to 90%, but was essentially independent of the drift field strength. A double conical GEM has a 10% gain increase with time due to surface charging by avalanche ions whereas this effect was eliminated with the cylindrical GEM. The positive-ion feedback is also estimated. (author)

  11. Fast front-end L0 trigger electronics for ALICE FMD-MCP tests and performance

    CERN Document Server

    Efimov, L G; Kasatkan, V; Klempt, W; Kuts, V; Lenti, V; Platanov, V; Rudge, A; Stolyarov, O I; Tsimbal, F A; Valiev, F F; Villalobos Baillie, O; Vinogradov, L I; Zhigunov, O

    1997-01-01

    We present design details and new measurements of the performance of fast electronics for the Forward Multiplicity Detector for ALICE. These detectors based on sector type Microchannel Plates (MCP) forming several disks gave the very first trigger decision in the experiment (L0). Fast passive summators integrated with the detectors are used for linear summation of up to eight isochronous signal channels from MCP pads belonging to one sector. Two types of microelectronics design thin film summators were produced. We present test results for these summators, working in the frequency range up to 1 Ghz. New low noise preamplifiers have been built to work with these summators. The new design shows a good performance with the usable frequency range extended up to 1 Ghz. An upgrade of the functional scheme for the L0 ALICE pre-trigger design is also presented.Abstract:List of figures Figure 1: ALICE L0 Trigger Front-End Electronics Functional Scheme. Figure 2: UHF design for a fast passive summator based on direct...

  12. Development of a thick gas electron multiplier for microdosimetry

    International Nuclear Information System (INIS)

    Orchard, G.M.; Chin, K.; Prestwich, W.V.; Waker, A.J.; Byun, S.H.

    2011-01-01

    A new tissue-equivalent proportional counter based on a thick gas electron multiplier (THGEM) was developed and tested for microdosimetry. A systematic test was conducted at the McMaster Accelerator Laboratory to investigate the overall performance of the prototype detector. A mixed neutron-gamma-ray radiation field was generated using the 7 Li(p,n) reaction. The detector was operated at low voltage initially to test the stability and then the relative multiplication gain was measured as a function of the operating high voltage. A drift potential of 100 V and a THGEM bias of 727 V generated a multiplication gain sufficient for the detection of both neutron and gamma-ray radiation. A consistent microdosimetric pattern was observed between the THGEM detector and standard TEPC for microdosimetry.

  13. Research on nonlinearity effect of secondary electron multiplier

    International Nuclear Information System (INIS)

    Wei Xingjian; Liao Junsheng; Deng Dachao; Yu Chunrong; Yuan Li

    2007-01-01

    The nonlinearity of secondary electron multiplier (SEM) of a thermal ionization mass spectrometer has been researched by using UTB-500 uranium isotope reference material and multi-collecting technique. The results show that the nonlinearity effect of SEM exists in the whole ion counting range, and there is an extreme point of the nonlinearity when the ion counting rate is about 20000 cps. The deviation between measured value of the extreme point and the reference value of the reference sample can be up to 3%, and the nonlinearity obeys logarithm linearity law on both sides of extreme point. A kind of mathematics model of nonlinearity calibration has been put forward. Using this model, the nonlinearity of SEM of TIMS can be calibrated. (authors)

  14. Microchannel electron multiplier: improvement in gain performances and detection dynamics

    International Nuclear Information System (INIS)

    Audier, M.; Delmotte, J.C.; Boutot, J.P.

    1978-01-01

    The performances of an MCP are a function of its geometrical characteristics (diameter d and ratio 1/d of a channel, useful area) and of the applied voltage. Gain and mean output current are limited by saturation phenomena. By using a particular cascaded MCP's configuration, it is possible to simultaneously improve the gain, its associated fluctuations and the detection dynamics (detected level, counting rate). For gains 10 6 7 , the fluctuations, can be kept as low as 20% and an improvement by a factor > 10 can be obtained on the detection dynamics [fr

  15. Investigation of image distortion due to MCP electronic readout misalignment and correction via customized GUI application

    Science.gov (United States)

    Vitucci, G.; Minniti, T.; Tremsin, A. S.; Kockelmann, W.; Gorini, G.

    2018-04-01

    The MCP-based neutron counting detector is a novel device that allows high spatial resolution and time-resolved neutron radiography and tomography with epithermal, thermal and cold neutrons. Time resolution is possible by the high readout speeds of ~ 1200 frames/sec, allowing high resolution event counting with relatively high rates without spatial resolution degradation due to event overlaps. The electronic readout is based on a Timepix sensor, a CMOS pixel readout chip developed at CERN. Currently, a geometry of a quad Timepix detector is used with an active format of 28 × 28 mm2 limited by the size of the Timepix quad (2 × 2 chips) readout. Measurements of a set of high-precision micrometers test samples have been performed at the Imaging and Materials Science & Engineering (IMAT) beamline operating at the ISIS spallation neutron source (U.K.). The aim of these experiments was the full characterization of the chip misalignment and of the gaps between each pad in the quad Timepix sensor. Such misalignment causes distortions of the recorded shape of the sample analyzed. We present in this work a post-processing image procedure that considers and corrects these effects. Results of the correction will be discussed and the efficacy of this method evaluated.

  16. Exponential decay and exponential recovery of modal gains in high count rate channel electron multipliers

    International Nuclear Information System (INIS)

    Hahn, S.F.; Burch, J.L.

    1980-01-01

    A series of data on high count rate channel electron multipliers revealed an initial drop and subsequent recovery of gains in exponential fashion. The FWHM of the pulse height distribution at the initial stage of testing can be used as a good criterion for the selection of operating bias voltage of the channel electron multiplier

  17. Investigation of the Decelerating Field of an Electron Multiplier under Negative Ion Impact

    DEFF Research Database (Denmark)

    Larsen, Elfinn; Kjeldgaard, K.

    1973-01-01

    The effect of the decelerating field of an electron multiplier towards negative ions was investigated under standard mass spectrometric conditions. Diminishing of this decelerating field by changing of the potential of the electron multiplier increased the overall sensitivity to negative ions...

  18. Ionizing device comprising a microchannel electron multiplier with secondary electron emission

    International Nuclear Information System (INIS)

    Chalmeton, Vincent.

    1974-01-01

    The present invention relates to a ionizing device comprising a microchannel electron multiplier involving secondary electron emission as a means of ionization. A system of electrodes is used to accelerate said electrons, ionize the gas and extract the ions from thus created plasma. Said ionizer is suitable for bombarding the target in neutron sources (target of the type of nickel molybdenum coated with tritiated titanium or with a tritium deuterium mixture) [fr

  19. Effect of the channel electron multiplier connection diagram on its parameters

    International Nuclear Information System (INIS)

    Ajnbund, M.R.

    1976-01-01

    Basic alternatives of connection of a channel electron multiplier are described. A dependence of a gain factor and amplitude resolution of the channel electron multiplier upon its connection diagram is studied. The studies have shown that the maximum gain factor is typical of an open-output circuit where the signal is recorded from the anode of the channel electron multiplier at a potential with respect to the channel outlet. The highest amplitude resolution is inherent in a separate-anode circuit where the loading resistance is connected directly to the channel outlet

  20. Sheath formation of a plasma containing multiply charged ions, cold and hot electrons, and emitted electrons

    International Nuclear Information System (INIS)

    You, H.J.

    2012-01-01

    It is quite well known that ion confinement is an important factor in an electron cyclotron resonance ion source (ECRIS) as it is closely related to the plasma potential. A model of sheath formation was extended to a plasma containing multiply charged ions (MCIs), cold and hot electrons, and secondary electrons emitted either by MCIs or hot electrons. In the model, a modification of the 'Bohm criterion' was given, the sheath potential drop and the critical emission condition were also analyzed. It appears that the presence of hot electrons and emitted electrons strongly affects the sheath formation so that smaller hot electrons and larger emission current result in reduced sheath potential (or floating potential). However the sheath potential was found to become independent of the emission current J when J > J c , (where J c is the critical emission current. The paper is followed by the associated poster

  1. Utilization of a channel electron multiplier for counting-measurement on condensed molecular jet

    International Nuclear Information System (INIS)

    Le Bihan, A.M.; Bottiglioni, F.; Coutant, J.; Fois, M.; CEA Centre d'Etudes Nucleaires de Fontenay-aux-Roses, 92

    1974-01-01

    A channel electron multiplier has been used for counting ionized clusters containing up to a few thousands molecules; clusters are accelerated towards a negative (approximately-220V) copper target; a larger negative bias (approximately-3000V) is applied to the multiplier entrance so as to collect positive secondary ions and/or reflected cluster fragments; in the present application this gives better signal to noise ratio than detecting clusters directly or by secondary electron emission on the target [fr

  2. Electronic de-multipliers II (ring-shape systems); Demultiplieurs electroniques II (systeme en anneau)

    Energy Technology Data Exchange (ETDEWEB)

    Raievski, V

    1948-09-01

    This report describes a new type of ring-shape fast electronic counter (de-multiplier) with a resolution capacity equivalent to the one made by Regener (Rev. of Scientific Instruments USA 1946, 17, 180-89) but requiring two-times less electronic valves. This report follows the general description of electronic de-multipliers made by J. Ailloud (CEA--001). The ring comprises 5 flip-flop circuits with two valves each. The different elements of the ring are calculated with enough details to allow the transfer of this calculation to different valve types. (J.S.)

  3. High dynamic range isotope ratio measurements using an analog electron multiplier

    Czech Academy of Sciences Publication Activity Database

    Williams, P.; Lorinčík, Jan; Franzreb, K.; Herwig, R.

    2013-01-01

    Roč. 45, č. 1 (2013), s. 549-552 ISSN 0142-2421 R&D Projects: GA MŠk ME 894 Institutional support: RVO:67985882 Keywords : Isotope ratios * electron multiplier * dynamic range Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.393, year: 2013

  4. Colliding beam studies of electron detachement from H- by multiply-charged ions

    International Nuclear Information System (INIS)

    Melchert, F.; Benner, M.; Kruedener, S.; Schulze, R.; Meuser, S.; Pfaff, S.; Petri, S.; Huber, K.; Salzborn, E.; Presnyakov, L.P.; Uskov, D.B.

    1993-01-01

    Employing the crossed-beams technique, we have investigated electron-detachment processes from H - in collisions with multiply-charged noble gas ions A q+ . Absolute cross sections for single- and double-electron removal have been measured at center-of-mass energies from 50 keV to 200 keV and charge states q up to 8

  5. Modulated electron-multiplied fluorescence lifetime imaging microscope: all-solid-state camera for fluorescence lifetime imaging.

    Science.gov (United States)

    Zhao, Qiaole; Schelen, Ben; Schouten, Raymond; van den Oever, Rein; Leenen, René; van Kuijk, Harry; Peters, Inge; Polderdijk, Frank; Bosiers, Jan; Raspe, Marcel; Jalink, Kees; Geert Sander de Jong, Jan; van Geest, Bert; Stoop, Karel; Young, Ian Ted

    2012-12-01

    We have built an all-solid-state camera that is directly modulated at the pixel level for frequency-domain fluorescence lifetime imaging microscopy (FLIM) measurements. This novel camera eliminates the need for an image intensifier through the use of an application-specific charge coupled device design in a frequency-domain FLIM system. The first stage of evaluation for the camera has been carried out. Camera characteristics such as noise distribution, dark current influence, camera gain, sampling density, sensitivity, linearity of photometric response, and optical transfer function have been studied through experiments. We are able to do lifetime measurement using our modulated, electron-multiplied fluorescence lifetime imaging microscope (MEM-FLIM) camera for various objects, e.g., fluorescein solution, fixed green fluorescent protein (GFP) cells, and GFP-actin stained live cells. A detailed comparison of a conventional microchannel plate (MCP)-based FLIM system and the MEM-FLIM system is presented. The MEM-FLIM camera shows higher resolution and a better image quality. The MEM-FLIM camera provides a new opportunity for performing frequency-domain FLIM.

  6. Electron capture to autoionizing states of multiply charged ions

    International Nuclear Information System (INIS)

    Mack, E.M.

    1987-01-01

    The present thesis investigates electron capture reactions resulting from slow collisions (V q+ ) and neutral gas targets (B). The energy spectra of the emitted electrons are measured; detection angle is 50 0 . Mainly, autoionizing double capture resulting from collisions with two-electron targets (He, H 2 ) is studied; then, the emitted electrons stem from doubly excited projectile states. The projectiles used are bare C 6+ , the H-like and He-like ions of C, N and O, He-like Ne 8+ and Ne-like Ar 8+ . Excited metastable projectiles used are C 5+ (2s), He-like projectiles A q+ (1s2s 3 S) and Ar 8+ (...2p 5 3s). Comparison is made with the predictions of a recently proposed extended classical barrier model, that was developed in connection with the work. This model assumes sequential capture of the electrons ('two-step' process); it predicts the realized binding enegies of the captured electrons - which may be directly determined from the autoionization spectra using only the projectile charge, the ionization potentials of the target and the collision velocity as parameters. No adjustable parameter enters into the calculations. The term energies and decay modes of the highly excited product ions themselves are studied. Generally, the autoionizing decay of these states is found to proceed preferentially to the directly adjacent lower singly excited state. Experimental evidence is presented, that triply excited states decay by successive emission of two electrons, whenever this is energetically possible. Finally, the L-MM decay in few-electron systems is considered. 314 refs.; 96 figs.; 29 tabs

  7. Electronic shell structure in multiply charged silver clusters

    International Nuclear Information System (INIS)

    Kandler, O.; Athanassenas, K.; Echt, O.; Kreisle, D.; Leisner, T.; Recknagel, E.

    1991-01-01

    Silver clusters are generated by standard laser vaporization technique and ionized via multiphoton ionization. Time-of-flight mass spectrometry reveals singly, doubly and triply charged clusters, Ag n z+ (z=1, 2, 3). The spectra show, for all charge states, intensity variations, indicating enhanced stabilities for cluster sizes with closed electronic configurations in accord with the spherical jellium model. (orig.)

  8. Studies of collision mechanisms in electron capture by slow multiply charged ions

    International Nuclear Information System (INIS)

    Gilbody, H B; McCullough, R W

    2004-01-01

    We review measurements based on translational energy spectroscopy which are being used to identify and assess the relative importance of the various collision mechanisms involved in one-electron capture by slow multiply charged ions in collisions with simple atoms and molecules

  9. Database for inelastic collisions of lithium atoms with electrons, protons, and multiply charged ions

    NARCIS (Netherlands)

    Schweinzer, J; Brandenburg, R; Bray, [No Value; Hoekstra, R; Aumayr, F; Janev, RK; Winter, HP

    New experimental and theoretical cross-section data for inelastic collision processes of Li atoms in the ground state and excited states (up to n = 4) with electrons, protons, and multiply charged ions have been reported since the database assembled by Wutte et al. [ATOMIC DATA AND NUCLEAR DATA

  10. Electron and X-ray emission in collisions of multiply charged ions and atoms

    International Nuclear Information System (INIS)

    Woerlee, P.H.

    1979-01-01

    The author presents experimental results of electron and X-ray emission following slow collisions of multiply charged ions and atoms. The aim of the investigation was to study the mechanisms which are responsible for the emission. (G.T.H.)

  11. Electron loss from multiply protonated lysozyme ions in high energy collisions with molecular oxygen

    DEFF Research Database (Denmark)

    Hvelplund, P; Nielsen, SB; Sørensen, M

    2001-01-01

    We report on the electron loss from multiply protonated lysozyme ions Lys-Hn(n)+ (n = 7 - 17) and the concomitant formation of Lys-Hn(n+1)+. in high-energy collisions with molecular oxygen (laboratory kinetic energy = 50 x n keV). The cross section for electron loss increases with the charge state...... of the precursor from n = 7 to n = 11 and then remains constant when n increases further. The absolute size of the cross section ranges from 100 to 200 A2. The electron loss is modeled as an electron transfer process between lysozyme cations and molecular oxygen....

  12. Timing characteristics of the VEhU-6 microchannel electron multipliers

    International Nuclear Information System (INIS)

    Bakhtizin, R.Z.; Yumaguzin, Yu.M.

    1982-01-01

    The VEhU-6 charnel electron multiplier timing characteristics are experimentally studied. Dependence of monoelectron pulse duration at the VEhU-6 output at different values of channel supply voltage is investigated. The VEhU-6 delay time is measured. Delay time increased from 10 to 30 ns with the increase of channel supply voltage from 2.8 to 3.2 kV (at approximately 10 5 pulse/s loading). Delay time increases with loading decrease

  13. On the fast response of charnel electron multipliers in coUnting mode operation

    International Nuclear Information System (INIS)

    Belyaevskij, O.A.; Gladyshev, I.L.; Korobochko, Yu.S.; Mineev, V.I.

    1983-01-01

    Dependences of amplitude distribution of pulses at the outlet of channel electron multipliers (CEM) and effectiveness of monitoring on counting rate at different supply voltages are determined. It is shown that the maximUm counting rate of CEM runs into 6x10 5 s -1 at short-term and 10 5 s -1 at long-term operation using monitoring eqUipment with operation threshold of 2.5 mV

  14. Indirect mechanisms in electron-impact ionization of multiply charged ions

    International Nuclear Information System (INIS)

    Phaneuf, R.A.; Gregory, D.C.

    1986-09-01

    The important role of indirect-ionization mechanisms in electron-impact ionization of multiply charged ions has been emphasized by some recent experiments conducted with the ORNL-ECR multicharged ion source. Illustrative examples of investigations of the Mg-isoelectronic and Fe-isonuclear sequences are presented and compared with the results of detailed theoretical calculations. New experimental data is also presented concerning the role of resonance effects in the ionization of Li-like O 5+ and Na-like Fe 15+ ions

  15. Development of a time projection chamber using gas electron multipliers (GEM-TPC)

    International Nuclear Information System (INIS)

    Oda, S.X.; Hamagaki, H.; Ozawa, K.; Inuzuka, M.; Sakaguchi, T.; Isobe, T.; Gunji, T.; Morino, Y.; Saito, S.; Yamaguchi, Y.L.; Sawada, S.; Yokkaichi, S.

    2006-01-01

    We developed a prototype time projection chamber using gas electron multipliers (GEM-TPC) for high energy heavy ion collision experiments. To investigate its performance, we conducted a beam test with three kinds of gases (Ar(90%)-CH 4 (10%), Ar(70%)-C 2 H 6 (30%) and CF 4 ). Detection efficiency of 99%, and spatial resolution of 79μm in the pad-row direction and 313μm in the drift direction were achieved. The test results show that the GEM-TPC meets the requirements for high energy heavy ion collision experiments. The configuration and performance of the GEM-TPC are described

  16. A zerotime detector for nuclear fragments using channel electron multiplier plates

    International Nuclear Information System (INIS)

    Sundqvist, B.

    1975-01-01

    The literature on zerotime detectors which use the emission of secondary electrons from a thin foil is reviewed. The construction of a zerotime detector using multiplication of the secondary electrons with two Mullard channel electron multiplier plates (CEMP) in tandem is described. Results of tests of such a detector with α particles from a natural α source are given. Total time resolutions of about 200 ps (FWHM) with a Si(Sb) detector as the stop detector has been achieved. The contribution from the zerotime detector is estimated to be less than 150 ps (FWHM). The application of this detector technique to the construction of a heavy-ion spectrometer and a 8 Be detector is described. (Auth)

  17. Coupled-Multiplier Accelerator Produces High-Power Electron Beams for Industrial Applications

    International Nuclear Information System (INIS)

    Hatridge, M.; McIntyre, P.; Roberson, S.; Sattarov, A.; Thomas, E.; Meitzler, Charles

    2003-01-01

    The coupled multiplier is a new approach to efficient generation of MeV d.c. power for accelerator applications. High voltage is produced by a series of modules, each of which consists of a high-power alternator, step-up transformer, and 3-phase multiplier circuit. The alternators are connected mechanically along a rotating shaft, and connected by insulating flexible couplers. This approach differs from all previous d.c. technologies in that power is delivered to the various stages of the system mechanically, rather than through capacitive or inductive electrical coupling. For this reason the capital cost depends linearly on required voltage and power, rather than quadratically as with conventional technologies. The CM technology enables multiple electron beams to be driven within a common supply and insulating housing. MeV electron beam is extremely effective in decomposing organic contaminants in water. A 1 MeV, 100 kW industrial accelerator using the CM technology has been built and is being installed for treatment of wastewater at a petrochemical plant

  18. Analysis of microwave amplifier and frequency multiplier tube with a multipactor electron gun

    International Nuclear Information System (INIS)

    Yokoo, Kuniyoshi; Ono, Shoichi; Tai, Dong-Zhe.

    1983-01-01

    The performance analysis was made for a multipactor microwave tube with the aim of realizing a microwave amplifier or a frequency multiplier tube with a multipactor cathode with high efficiency and high power. The possibility for producing the multipactor tube with high efficiency and high power was shown by using effectively the characteristics of the multipactor cathode which emits pulsed electron current with narrow band, synchronizing with high frequency period. As the operating conditions for the multipactor cathode, it was shown that the wide spacing of the cathode was needed for the operation in high operating power, and the narrow spacing was needed for the operation in high efficiency and for reducing power consumption. It was also shown that there were the best values of the high-frequency voltage for the cathode operation. The study by the simulation for the multipactor cathode and for the acceleration zone of electron current was also performed to examine the possible performance for a microwave amplifier and a frequency multiplier tube. For the use of the multipactor cathode with a spacing of 1 mm, the conversion efficiency for d. c. input power was 86, 56 and 31 % for the primary, the secondary and the tertiary harmonic wave amplifications, respectively. (Asami, T.)

  19. Detection of X-ray fluorescence of light elements by electron counting in a low-pressure gaseous electron multiplier

    International Nuclear Information System (INIS)

    Pansky, A.; Breskin, A.; Chechik, R.; Malamud, G.

    1992-12-01

    Ionization electrons deposited by soft X-rays in a low pressure (10 Torr) gas medium are efficiently counted by a multistage electron multiplier, providing an accurate measurement of the X-ray photon energy. Energy resolution of 56-28% FWHM were measured for X-rays of 110-676 eV, recording electrical induced charges or visible photons emitted during the avalanche process. It is demonstrated that a combined analysis of the number of electron trail length of an event, provides a powerful and competitive way of resolving ultra soft X-rays. We present the experimental technique, discuss the advantages and limitations of the Primary Electron Counter, and suggest ways to improve its performances. (authors)

  20. Removal of contaminating tritium and tritium pressure measurement by a secondary electron multiplier

    International Nuclear Information System (INIS)

    Ichimura, K.; Watanabe, K.; Nishizawa, K.; Fujita, J.

    1984-01-01

    A ceramic secondary electron multiplier (SEM), Ceratron, was used to study impairment of the SEM performance due to adsorbed tritium, its decontamination, and the applicability of the SEM to measure tritium pressure. The background level of the SEM increased significantly, up to its counting limit, due to tritium adsorption. Heating it to 300 0 C in vacuo and/or in the presence of reactive gases such as D 2 and CO at 1 x 10 -4 Pa was not effective to decontaminate the SEM, whereas photon irradiation was extremely powerful for the decontamination. The tritium (HT) pressure in a range of 1 x 10 -6 - 1 x 10 -3 Pa could be measured with no significant impairment of the SEM performance with the aid of photon irradiation. It is revealed that a particle flux as low as 1 particle/s will be able to measure in the presence of tritium if suitable photon sources are installed in the systems. (orig.)

  1. Gas electron multiplier (GEM) foil test, repair and effective gain calculation

    Science.gov (United States)

    Tahir, Muhammad; Zubair, Muhammad; Khan, Tufail A.; Khan, Ashfaq; Malook, Asad

    2018-06-01

    The focus of my research is based on the gas electron multiplier (GEM) foil test, repairing and effective gain calculation of GEM detector. During my research work define procedure of GEM foil testing short-circuit, detection short-circuits in the foil. Study different ways to remove the short circuits in the foils. Set and define the GEM foil testing procedures in the open air, and with nitrogen gas. Measure the leakage current of the foil and applying different voltages with specified step size. Define the Quality Control (QC) tests and different components of GEM detectors before assembly. Calculate the effective gain of GEM detectors using 109Cd and 55Fe radioactive source.

  2. High- and low-pressure operation of the gas electron multiplier

    International Nuclear Information System (INIS)

    Bondar, A.; Buzulutskov, A.; Shekhtman, L.; Sauli, F.

    1998-01-01

    We have studied the operation of the gas electron multiplier (GEM) in gas mixtures Xe-CO 2 , Ar-CO 2 and CH 4 at different pressures varying from 0.1 to 5 atm. In Ar- and Xe-based mixtures, the maximum GEM gain considerably decreases with pressure, from a few hundreds at 1 atm to below 10 at 5 atm. Combined gain of GEM and the micro-strip gas chamber (MSGC) can exceed values of 10000 at 1 atm and 100 at 5 atm. High GEM gains, of above 1000, were obtained in CH 4 at low pressures. We have observed the effect of the avalanche confinement in GEM micro-holes, resulting in violation of the pressure scaling and in the possibility of GEM operation in pure noble gases. (author)

  3. Performance test of a micro-pattern stereo detector with two gas electron multipliers

    International Nuclear Information System (INIS)

    Barvich, T.; Bluem, P.; Erdmann, M.; Fahrer, M.; Kaercher, K.; Kuehn, F.; Moermann, D.; Mueller, Th.; Neuberger, D.; Roederer, F.; Simonis, H.J.; Skiba, A.; Thuemmel, W.H.; Weiler, Th.; Weseler, S.

    2002-01-01

    We report on the performance of a large micro-pattern detector with two gas electron multiplier foils and a two-layer readout structure at ground potential. The two readout layers each have a 406 μm pitch and cross at an effective angle of 6.7 deg. . This structure allows for two orthogonal coordinates to be determined. Using a muon beam at CERN together with a silicon tracking system, the position resolutions of the two coordinates are measured to be 50 μm and 1 mm respectively (1 standard deviation). The muon detection efficiency for the two-dimensional space points reaches 96%. The detector was found to be well operational over a wide range in the settings of the different electrical fields

  4. Gas electron multiplier (GEM) operation with tissue-equivalent gases at various pressures

    International Nuclear Information System (INIS)

    Farahmand, M.; Bos, A.J.J.; Eijk, C.W.E. van

    2003-01-01

    We have studied the operation of two different Gas Electron Multiplier (GEM) structures in both methane and propane based Tissue-Equivalent (TE) gases at different pressures varying from 0.1 to 1 atm. This work was motivated to explore the possibility of using a GEM for a new type of Tissue Equivalent Proportional Counter. In methane based TE gas, a maximum safe GEM gain of 1.5x10 3 has been reached while in propane based TE gas this is 6x10 3 . These maxima have been reached at different gas pressures depending on GEM structure and TE gas. Furthermore, we observed a decrease of the GEM gain in time before it becomes stable. Charge up/polarisation effects can explain this

  5. Electron cyclotron resonance (E.C.R.) multiply charged ion sources

    International Nuclear Information System (INIS)

    Geller, R.

    1978-01-01

    High charge state ions can be produced by electron bombardment inside targets when the target electron density n (cm -3 ) multiplied by the ion transit time through the target tau (sec) is: n tau > 5.10 9 cm -3 sec. The relative velocity between electrons and ions determines the balance between stripping and capture i.e. the final ion charge state. (In a stripper foil fast ions interact with slow electrons involving typically n approximately 10 24 cm -3 , tau approximately 10 -14 sec). In the E.C.R. source a cold ion plasma created in a first stage diffuses slowly through a second stage containing a hot E.C.R. plasma with n > 3.10 11 cm -3 and tau > 10 -2 sec. Continuous beams of several μA of C 6+ N 7+ Ne 9+ A 11+ are extracted from the second stage with normalized emittances of approximately 0.5 π mm mrad. The absence of cathodes and plasma arcs makes the source very robust, reliable and well-fitted for cyclotron injection. A super conducting source is under development

  6. Multicascade X-Ray Free-Electron Laser with Harmonic Multiplier and Two-Frequency Undulator

    Science.gov (United States)

    Zhukovsky, K. V.

    2018-06-01

    The feasibility of generation of powerful x-ray radiation by a cascade free-electron laser (FEL) with amplification of higher harmonics using a two-frequency undulator is studied. To analyze the FEL operation, a complex phenomenological single-pass FEL model is developed and used. It describes linear and nonlinear generation of harmonics in the FEL with seed laser that takes into account initial electron beam noise and describes all main losses of each harmonic in each FEL cascade. The model is also calibrated against and approved by the experimental FEL data and available results of three-dimensional numerical simulation. The electron beam in the undulator is assumed to be matched and focused, and the dynamics of power in the singlepass FEL with cascade harmonic multipliers is investigated to obtain x-ray laser radiation in the FEL having the shortest length, beam energy, and frequency of the seed laser as low as possible. In this context, the advantages of the two-frequency undulator used for generation of harmonics are demonstrated. The evolution of harmonics in a multicascade FEL with multiplication of harmonics is investigated. The operation of the cascade FEL at the wavelength λ = 1.14 nm, generating 30 MW already on 38 m with the seed laser operating at a wavelength of 11.43 nm corresponding to the maximal reflectivity of the multilayered mirror MoRu/Be coating is investigated. In addition, the operation of the multicascade FEL with accessible seed UVlaser operating at a wavelength of 157 nm (F2 excimer UV-laser) and electron beam with energy of 0.5 GeV is investigated. X-ray radiation simulated in it at the wavelength λ 3.9 nm reaches power of 50 MW already at 27 m, which is by two orders of magnitude shorter than 3.4 km of the x-ray FEL recently put into operation in Europe.

  7. Secondary scintillation yield from GEM and THGEM gaseous electron multipliers for direct dark matter search

    Science.gov (United States)

    Monteiro, C. M. B.; Fernandes, L. M. P.; Veloso, J. F. C. A.; Oliveira, C. A. B.; dos Santos, J. M. F.

    2012-07-01

    The search for alternatives to PMTs as photosensors in optical TPCs for rare event detection has significantly increased in the last few years. In particular, in view of the next generation large volume detectors, the use of photosensors with lower natural radioactivity, such as large area APDs or GM-APDs, with the additional possibility of sparse surface coverage, triggered the intense study of secondary scintillation production in micropattern electron multipliers, such as GEMs and THGEMs, as alternatives to the commonly used uniform electric field region between two parallel meshes. The much higher scintillation output obtained from the electron avalanches in such microstructures presents an advantage in those situations. The accurate knowledge of the amount of such scintillation is important for correct detector simulation and optimization. It will also serve as a benchmark for software tools developed and/or under development for the calculation of the amount of such scintillation.The secondary scintillation yield, or electroluminescence yield, in the electron avalanches of GEMs and THGEMs operating in gaseous xenon and argon has been determined for different gas pressures. At 1 bar, THGEMs deliver electroluminescence yields that are more than one order of magnitude higher when compared to those achieved in GEMs and two orders of magnitude when compared to those achieved in a uniform field gap. The THGEM electroluminescence yield presents a faster decrease with pressure when comparing to the GEM electroluminescence yield, reaching similar values to what is achieved in GEMs for xenon pressures of 2.5 bar, but still one order of magnitude higher than that produced in a uniform field gap. Another exception is the GEM operating in argon, which presents an electroluminescence yield similar to that produced in a uniform electric field gap, while the THGEM achieves yields that are more than one order of magnitude higher.

  8. A Monte Carlo simulation of the microdosimetric response for thick gas electron multiplier

    International Nuclear Information System (INIS)

    Hanu, A.; Byun, S.H.; Prestwich, W.V.

    2010-01-01

    The neutron microdosimetric responses of the thick gas electron multiplier (THGEM) detector were simulated. The THGEM is a promising device for microdosimetry, particularly for measuring the dose spectra of intense radiation fields and for collecting two-dimensional microdosimetric distributions. To investigate the response of the prototype THGEM microdosimetric detector, a simulation was developed using the Geant4 Monte Carlo code. The simulation calculates the deposited energy in the detector sensitive volume for an incident neutron beam. Both neutron energy and angular responses were computed for various neutron beam conditions. The energy response was compared with the reported experimental microdosimetric spectra as well as the evaluated fluence-to-kerma conversion coefficients. The effects of using non-tissue equivalent materials were also investigated by comparing the THGEM detector response with the response of an ideal detector in identical neutron field conditions. The result of the angular response simulations revealed severe angular dependencies for neutron energies above 100 keV. The simulation of a modified detector design gave an angular response pattern close to the ideal case, showing a fluctuation of less than 10% over the entire angular range.

  9. Gas Electron Multipliers: Development of large area GEMs and spherical GEMs

    CERN Document Server

    Duarte Pinto, Serge; Brock, Ian

    2011-01-01

    Gaseous radiation detectors have been a crucial part of high-energy physics instrumentation since the 1960s, when the first multiwire proportional counters were built. In the 1990s the first micropattern gas detectors (MPGDs) saw the light; with sub-millimeter feature sizes these novel detectors were faster and more accurate than their predecessors. The gas electron multiplier (GEM) is one of the most successful of these technologies. It is a charge multiplication structure made from a copper clad polymer foil, pierced with a regular and dense pattern of holes. I will describe the properties and the application of GEMs and GEM detectors, and the research and development I have done on this technology. Two of the main objectives were the development of large area GEMs (~m^2) for particle physics experiments and GEMs with a spherical shape for x-ray or neutron diffraction detectors. Both have been realized, and the new techniques involved are finding their way to applications in research and industry.

  10. Gas electron multipliers. Development of large area GEMS and spherical GEMS

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, Serge Duarte

    2011-08-15

    Gaseous radiation detectors have been a crucial part of high-energy physics instrumentation since the 1960s, when the first multiwire proportional counters were built. In the 1990s the first micropattern gas detectors (MPGDS) saw the light; with sub-millimeter feature sizes these novel detectors were faster and more accurate than their predecessors. The gas electron multiplier (GEM) is one of the most successful of these technologies. It is a charge multiplication structure made from a copper clad polymer foil, pierced with a regular and dense pattern of holes. I describe the properties and the application of GEMs and GEM. detectors, and the research and development I have done on this technology. Two of the main objectives were the development of large area GEMs ({proportional_to}m{sup 2}) for particle physics experiments and GEMs with a spherical shape for X-ray or neutron diffraction detectors. Both have been realized, and the new techniques involved are finding their way to applications in research and industry. (orig.)

  11. The current status of the Gas Electron Multiplier (GEM) research at Kasetsart University, Thailand

    Science.gov (United States)

    Kumpiranon, P.; Kulasri, K.; Rittirong, A.; Saenboonruang, K.

    2017-06-01

    During the past decade, Gas Electron Multiplier (GEM) detectors have been greatly developed and utilized in numbers of applications including advanced nuclear and particle researches, medical imaging, astrophysics, and neutron detection for national security. Our GEM research group at the Department of Applied Radiation and Isotopes, Faculty of Science, Kasetsart University, Thailand, realized in its excellent properties/potentials and started extensive researches on GEM detectors. To build a strong foundation on our research group, two 10 cm × 10 cm triple GEM detectors were characterized on their important properties including absolute gains and detection uniformity. Moreover, to widen applications of the GEM detector, our group had modified the GEM detector by introducing either solid or gaseous neutron converters to the detector so that the detector could effectively detect neutrons. These modifications included coating a thin film of 10B and natB to the GEM drift cathode for thermal neutron detection and flowing a gas mixture of He/CO2 (80:20 and 70:30) and C4H10/He/CO2 (7:70:23) for fast neutron detection. Results showed that the modified GEM-based neutron detector could detect both types of neutrons with different relative efficiencies and gains depending on thicknesses and types of neutron converters. This article discusses basic knowledge of the GEM detector, construction and testing procedures, results, and discussion.

  12. Gas electron multipliers: Development of large area GEMS and spherical GEMS

    International Nuclear Information System (INIS)

    Pinto, Serge Duarte

    2011-08-01

    Gaseous radiation detectors have been a crucial part of high-energy physics instrumentation since the 1960s, when the first multiwire proportional counters were built. In the 1990s the first micropattern gas detectors (MPGDS) saw the light; with sub-millimeter feature sizes these novel detectors were faster and more accurate than their predecessors. The gas electron multiplier (GEM) is one of the most successful of these technologies. It is a charge multiplication structure made from a copper clad polymer foil, pierced with a regular and dense pattern of holes. I describe the properties and the application of GEMs and GEM. detectors, and the research and development I have done on this technology. Two of the main objectives were the development of large area GEMs (∝m 2 ) for particle physics experiments and GEMs with a spherical shape for X-ray or neutron diffraction detectors. Both have been realized, and the new techniques involved are finding their way to applications in research and industry. (orig.)

  13. TOF-SIMA analysis of coating on MCP

    International Nuclear Information System (INIS)

    Luo Chunping; Liang Handong; Sun Dongxu

    2007-01-01

    Microchannel plate (MCP) is a sophisticated electronic optical device. It has advantages of high gain, small size, and low using voltage as a detector. The electronic transmission film on the MCP input plane could effectively avoid the positive ion feedback, and protect the photocathode, eliminate flicker noise, and prolong the lifespan of the device. In conclusion, the different films of the input plane can affect the performance of the MCP. Therefore, there is practical value to study surface coating composition of MCP for understanding the relationship between composition and performance and developing high-powered MCP. In the experiment, TOF-SIMS is used to study the surface coating composition of MCP. The results show that there are some main metal elements such as Si, K, Cr, Ni, Rh, Cs and Pb in the surface of the MCP. (authors)

  14. User's manual for EXALPHA (a code for calculating electronic properties of molecules). [Muscatel code, multiply scattered electron approximation

    Energy Technology Data Exchange (ETDEWEB)

    Jones, H.D.

    1976-06-01

    The EXALPHA procedures provide a simplified method for running the MUSCATEL computer code, which in turn is used for calculating electronic properties of simple molecules and atomic clusters, based on the multiply scattered electron approximation for the wave equations. The use of the EXALPHA procedures to set up a run of MUSCATEL is described.

  15. Studies of MCP properties

    International Nuclear Information System (INIS)

    Lehmann, A; Britting, A; Eyrich, W; Uhlig, F

    2009-01-01

    Cherenkov detectors of the DIRC type will be used for the particle identification of the PANDA experiment at FAIR. Because of their advantageous properties inside a magnetic field micro-channel plate (MCP) photomultipliers (PMT) are very attractive photon sensors for the two PANDA DIRCs. Various types of MCP-PMTs were investigated. Their gains and their time resolutions were measured as a function of the magnitude and the direction of a magnetic field. It was found that with a pore size of ≤ 10 μm efficient single photon detection is possible even at 2 Tesla if the field direction is close to parallel to the PMT axis. The gain of most of the studied MCP-PMTs remains stable up to a photon density of roughly 1 MHz/cm 2 , while the new Hamamatsu R10754-00-L4 can stand rates of about 10 MHz/cm 2 before the gain starts decreasing. The time resolution of all investigated MCP-PMTs was better than 50 ps (σ). The response of the multi-anode MCP-PMTs was scanned as a function of the position of the photo cathode plane in particular to measure the crosstalk among adjacent pixels. Most of the sensors show a satisfactory behavior.

  16. Ion Feedback Suppression Using Inclined MCP Holes in a Single-MCP+Micromegas+Pads Detector

    International Nuclear Information System (INIS)

    Va'vra, J.; Sumiyoshi, T.

    2005-01-01

    We show that the ion backflow to photocathode can be completely suppressed if one uses inclined MCP holes in a presence of magnetic field. The inclined hole angles are chosen to be aligned with the Lorentz electron angle allowing the electron transmission and amplification, while positive ions, traveling along a different angle, are caught on the MCP hole walls. The detector under investigation is a new gaseous detector structure based on a tandem of two parts, a single MCP (Microchannel) plate, a Micromegas with pad readout. We are aiming to develop a gaseous photon detector with the Bialkali photocathode, however, one could use some ideas in the paper for other types of detectors

  17. A how-to approach for a 3D simulation of charge transfer characteristics in a gas electron multiplier (GEM)

    CERN Document Server

    Sharma, A

    1999-01-01

    In this paper a detailed description of how to simulate charge transfer processes in a gaseous device is presented, taking the gas electron multiplier (GEM) as an example. A 3-dimensional simulation of the electric field and avalanche is performed. Results on charge transport are compared to experiment and agree within experimental errors; the avalanche mechanism and positive ion feedback are studied. The procedures used in the simulation are described in detail, and program scripts are appended. (15 refs).

  18. Photoionisation detection of single 87Rb-atoms using channel electron multipliers

    International Nuclear Information System (INIS)

    Henkel, Florian Alexander

    2011-01-01

    Fast and efficient detection of single atoms is a universal requirement concerning modern experiments in atom physics, quantum optics, and precision spectroscopy. In particular for future quantum information and quantum communication technologies, the efficient readout of qubit states encoded in single atoms or ions is an elementary prerequisite. The rapid development in the field of quantum optics and atom optics in the recent years has enabled to prepare individual atoms as quantum memories or arrays of single atoms as qubit registers. With such systems, the implementation of quantum computation or quantum communication protocols seems feasible. This thesis describes a novel detection scheme which enables fast and efficient state analysis of single neutral atoms. The detection scheme is based on photoionisation and consists of two parts: the hyperfine-state selective photoionisation of single atoms and the registration of the generated photoion-electron pairs via two channel electron multipliers (CEMs). In this work, both parts were investigated in two separate experiments. For the first step, a photoionisation probability of p ion =0.991 within an ionisation time of t ion =386 ns is achieved for a single 87 Rb-atom in an optical dipole trap. For the second part, a compact detection system for the ionisation fragments was developed consisting of two opposing CEM detectors. Measurements show that single neutral atoms can be detected via their ionisation fragments with a detection efficiency of η atom =0.991 within a detection time of t det =415.5 ns. In a future combined setup, this will allow the state-selective readout of optically trapped, single neutral 87 Rb-atoms via photoionisation detection with an estimated detection efficiency η=0.982 and a detection time of t tot = 802 ns. Although initially developed for single 87 Rb-atoms, the concept of photoionisation detection is in principle generally applicable to any atomic or molecular species. As efficient

  19. Photoionisation detection of single {sup 87}Rb-atoms using channel electron multipliers

    Energy Technology Data Exchange (ETDEWEB)

    Henkel, Florian Alexander

    2011-09-02

    Fast and efficient detection of single atoms is a universal requirement concerning modern experiments in atom physics, quantum optics, and precision spectroscopy. In particular for future quantum information and quantum communication technologies, the efficient readout of qubit states encoded in single atoms or ions is an elementary prerequisite. The rapid development in the field of quantum optics and atom optics in the recent years has enabled to prepare individual atoms as quantum memories or arrays of single atoms as qubit registers. With such systems, the implementation of quantum computation or quantum communication protocols seems feasible. This thesis describes a novel detection scheme which enables fast and efficient state analysis of single neutral atoms. The detection scheme is based on photoionisation and consists of two parts: the hyperfine-state selective photoionisation of single atoms and the registration of the generated photoion-electron pairs via two channel electron multipliers (CEMs). In this work, both parts were investigated in two separate experiments. For the first step, a photoionisation probability of p{sub ion}=0.991 within an ionisation time of t{sub ion}=386 ns is achieved for a single {sup 87}Rb-atom in an optical dipole trap. For the second part, a compact detection system for the ionisation fragments was developed consisting of two opposing CEM detectors. Measurements show that single neutral atoms can be detected via their ionisation fragments with a detection efficiency of {eta}{sub atom}=0.991 within a detection time of t{sub det}=415.5 ns. In a future combined setup, this will allow the state-selective readout of optically trapped, single neutral {sup 87}Rb-atoms via photoionisation detection with an estimated detection efficiency {eta}=0.982 and a detection time of t{sub tot} = 802 ns. Although initially developed for single {sup 87}Rb-atoms, the concept of photoionisation detection is in principle generally applicable to any

  20. Cross-Calibration of Secondary Electron Multiplier in Noble Gas Analysis

    Science.gov (United States)

    Santato, Alessandro; Hamilton, Doug; Deerberg, Michael; Wijbrans, Jan; Kuiper, Klaudia; Bouman, Claudia

    2015-04-01

    The latest generation of multi-collector noble gas mass spectrometers has decisively improved the precision in isotopic ratio analysis [1, 2] and helped the scientific community to address new questions [3]. Measuring numerous isotopes simultaneously has two significant advantages: firstly, any fluctuations in signal intensity have no effect on the isotope ratio and secondly, the analysis time is reduced. This particular point becomes very important in static vacuum mass spectrometry where during the analysis, the signal intensity decays and at the same time the background increases. However, when multi-collector analysis is utilized, it is necessary to pay special attention to the cross calibration of the detectors. This is a key point in order to have accurate and reproducible isotopic ratios. In isotope ratio mass spectrometry, with regard to the type of detector (i.e. Faraday or Secondary Electron Multiplier, SEM), analytical technique (TIMS, MC-ICP-MS or IRMS) and isotope system of interest, several techniques are currently applied to cross-calibrate the detectors. Specifically, the gain of the Faraday cups is generally stable and only the associated amplifier must be calibrated. For example, on the Thermo Scientific instrument control systems, the 1011 and 1012 ohm amplifiers can easily be calibrated through a fully software controlled procedure by inputting a constant electric signal to each amplifier sequentially [4]. On the other hand, the yield of the SEMs can drift up to 0.2% / hour and other techniques such as peak hopping, standard-sample bracketing and multi-dynamic measurement must be used. Peak hopping allows the detectors to be calibrated by measuring an ion beam of constant intensity across the detectors whereas standard-sample bracketing corrects the drift of the detectors through the analysis of a reference standard of a known isotopic ratio. If at least one isotopic pair of the sample is known, multi-dynamic measurement can be used; in this

  1. Study of the electric field inside microchannel plate multipliers

    International Nuclear Information System (INIS)

    Gatti, E.; Oba, K.; Rehak, P.

    1982-01-01

    Electric field inside high gain microchannel plate multipliers was studied. The calculations were based directly on the solution of the Maxwell equations applied to the microchannel plate (MCP) rather than on the conventional lumped RC model. The results are important to explain the performance of MCP's, (1) under a pulsed bias tension and, (2) at high rate conditions. The results were tested experimentally and a new method of MCP operation free from the positive ion feedback was demonstrated

  2. Statistics of electron multiplication in a multiplier phototube; Iterative method; Estadistica de la multiplicacion de electrones en un fotomultiplicador: Metodos iterativos

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz, J F; Grau, A

    1985-07-01

    In the present paper an iterative method is applied to study the variation of dynode response in the multiplier phototube. Three different situation are considered that correspond to the following ways of electronic incidence on the first dynode: incidence of exactly one electron, incidence of exactly r electrons and incidence of an average r electrons. The responses are given for a number of steps between 1 and 5, and for values of the multiplication factor of 2.1, 2.5, 3 and 5. We study also the variance, the skewness and the excess of jurtosis for different multiplication factors. (Author) 11 refs.

  3. Self-sputtering runaway in high power impulse magnetron sputtering: The role of secondary electrons and multiply charged metal ions

    International Nuclear Information System (INIS)

    Anders, Andre

    2008-01-01

    Self-sputtering runaway in high power impulse magnetron sputtering is closely related to the appearance of multiply charged ions. This conclusion is based on the properties of potential emission of secondary electrons and energy balance considerations. The effect is especially strong for materials whose sputtering yield is marginally greater than unity. The absolute deposition rate increases ∼Q 1/2 , whereas the rate normalized to the average power decreases ∼Q -1/2 , with Q being the mean ion charge state number

  4. Multiply ionization of diethyl ether clusters by 532 nm nanosecond laser: The influence of laser intensity and the electron energy distribution

    International Nuclear Information System (INIS)

    Zhang Nazhen; Wang Weiguo; Zhao Wuduo; Han Fenglei; Li Haiyang

    2010-01-01

    Graphical abstract: The formation mechanism for multiply charged ions (C q+ and O q+ (q = 2-4)) were investigated experimentally and theoretically using a dual polarity time-of-flight mass spectrometer when diethyl ether clusters interacted with nanosecond laser pulse. - Abstract: The formation mechanism for multiply charged ions (C q+ and O q+ (q = 2-4)) were investigated using a dual polarity time-of-flight mass spectrometer when diethyl ether clusters interacted with nanosecond laser pulse. The signal intensity of multiply charged ions and electron energy was measured experimentally. It was shown that the intensity of multiply charged ions increased about 50 times when laser intensity increased from 7.6 x 10 9 to 7.0 x 10 10 W/cm 2 , then saturated as laser intensity increased further. It is interesting that the evolution of the mean value of electron energy was same to that of multiply charged ions. The theoretical calculation showed the ionization potential of atomic ions could be significantly decreased due to the effect of Coulomb screening especially at low laser intensity. It indicated that the electron ionization combined with Coulomb screening effect could explain the production of multiply charged ions in nanosecond laser field.

  5. Development of a dual MCP framing camera for high energy x-rays

    Energy Technology Data Exchange (ETDEWEB)

    Izumi, N., E-mail: izumi2@llnl.gov; Hall, G. N.; Carpenter, A. C.; Allen, F. V.; Cruz, J. G.; Felker, B.; Hargrove, D.; Holder, J.; Lumbard, A.; Montesanti, R.; Palmer, N. E.; Piston, K.; Stone, G.; Thao, M.; Vern, R.; Zacharias, R.; Landen, O. L.; Tommasini, R.; Bradley, D. K.; Bell, P. M. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); and others

    2014-11-15

    Recently developed diagnostic techniques at LLNL require recording backlit images of extremely dense imploded plasmas using hard x-rays, and demand the detector to be sensitive to photons with energies higher than 50 keV [R. Tommasini et al., Phys. Phys. Plasmas 18, 056309 (2011); G. N. Hall et al., “AXIS: An instrument for imaging Compton radiographs using ARC on the NIF,” Rev. Sci. Instrum. (these proceedings)]. To increase the sensitivity in the high energy region, we propose to use a combination of two MCPs. The first MCP is operated in a low gain regime and works as a thick photocathode, and the second MCP works as a high gain electron multiplier. We tested the concept of this dual MCP configuration and succeeded in obtaining a detective quantum efficiency of 4.5% for 59 keV x-rays, 3 times larger than with a single plate of the thickness typically used in NIF framing cameras.

  6. Multi-anode photon-multiplier readout electronics for the LHCb ring imaging Cherenkov detectors

    CERN Document Server

    Smale, N J

    2004-01-01

    A readout system for the Ring Imaging CHerenkov (RICH) detectors of the LHCb experiment has been developed. Two detector technologies for the measurement of Cherenkov photons are considered, the Multi-Anode Photo-Multiplier Tube (MAPMT) and the Hybrid Photon Detector (HPD), both of which meet the RICH requirements. The properties of the MAPMT are evaluated using a controlled single-photon source; a pixel-to-pixel gain variation of ~3 and a typical signal to noise of ~20 is measured. The relative tube efficiency is found to be reduced by ~26 % due to the detailed focusing structure of the MAPMT device. A radiation hard application-specific integrated circuit (ASIC) chip, the Beetle1.2MA0, has been developed to capture and store signals from a pair of MAPMTs. The Beetle1.2MA0 is built on the architecture of the Beetle family that was designed for silicon strip detectors, the difference being a modified front-end amplifier. The 128 input-channels of the Beetle1.2MA0 have a charge-sensitive pre-amplifier followed...

  7. Ion feedback suppression using inclined MCP holes in a 'single-MCP+micromegas+pads' detector

    International Nuclear Information System (INIS)

    Va'vra, J.; Sumiyoshi, T.

    2005-01-01

    We show that the ion backflow to photocathode can be completely suppressed if one uses inclined MCP holes in the presence of a magnetic field. The inclined hole angles are chosen to be aligned with the Lorentz electron angle allowing the electron transmission and amplification, while positive ions, traveling along a different angle, are caught on the MCP hole walls. The detector under investigation is a new gaseous detector structure based on a tandem of two parts, a single MCP (microchannel plate), a micromegas with pad readout. We are aiming to develop a gaseous photon detector with the Bialkali photocathode, however, one could use some ideas in the paper for other types of detectors

  8. Electron loss process and cross section of multiply charged ions by neutral atoms

    International Nuclear Information System (INIS)

    Karashima, S.; Watanabe, T.

    1985-01-01

    The significance of experimental and theoretical results on the electron loss and capture of ions in matter plays an important role in the charge equilibrium problems of fusion plasma physics and of accelerator physics. In the report, we calculate electron stripping cross section by using the binary encounter approximation (BEA). Our treatment of the electron loss process is based on BEA, in which the nucleus of B screened by the surrounding electrons collides with electrons in the ion A sup(q+). The basic approximation in EBA is that the ion interacts with only one electron or nucleus of the target atom at a time. In the calculation for Li sup(2+) + H, we have found that EBA will give approximately reliable results. (Mori, K.)

  9. The detection of hard x-rays (10-140 KeV) by channel plate electron multipliers

    International Nuclear Information System (INIS)

    Bateman, J.E.

    1976-12-01

    Results are presented indicating that hard X-rays in the energy range 10 to 50 keV can be detected with good efficiency (5 to 10%) in channel plate electron multipliers (CPEM). From 50 keV to 140 keV the detection efficiency lies in the range 1 to 2%. A simple physical model is developed which indicates that not only can good detection efficiency be obtained but that very good X-ray imaging is possible. The model predicts that with further development, a wideband, hard X-ray detector can be realised with a detection efficiency in the range 5 to 20% and spatial response better than 10 lp/mm in the energy range 10 to 140 keV. (author)

  10. Gaseous electron multiplier-based soft x-ray plasma diagnostics development: Preliminary tests at ASDEX Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Chernyshova, M., E-mail: maryna.chernyshova@ipplm.pl; Malinowski, K.; Czarski, T.; Kowalska-Strzęciwilk, E. [Institute of Plasma Physics and Laser Microfusion, Hery 23, 01-497 Warsaw (Poland); Wojeński, A.; Poźniak, K. T.; Kasprowicz, G.; Krawczyk, R.; Kolasiński, P.; Zabołotny, W.; Zienkiewicz, P. [Institute of Electronic Systems, Warsaw University of Technology, Nowowiejska 15/19, 00-665 Warsaw (Poland); Vezinet, D.; Herrmann, A. [Max Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Mazon, D.; Jardin, A. [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France)

    2016-11-15

    A Gaseous Electron Multiplier (GEM)-based detector is being developed for soft X-ray diagnostics on tokamaks. Its main goal is to facilitate transport studies of impurities like tungsten. Such studies are very relevant to ITER, where the excessive accumulation of impurities in the plasma core should be avoided. This contribution provides details of the preliminary tests at ASDEX Upgrade (AUG) with a focus on the most important aspects for detector operation in harsh radiation environment. It was shown that both spatially and spectrally resolved data could be collected, in a reasonable agreement with other AUG diagnostics. Contributions to the GEM signal include also hard X-rays, gammas, and neutrons. First simulations of the effect of high-energy photons have helped understanding these contributions.

  11. Electron beam effects on the spectroscopy of multiply charged ions in plasma focus experiments

    International Nuclear Information System (INIS)

    Abdallah, J.; Clark, R.E.H.; Faenov, A.Y.; Karpinski, L.; Pikuz, S.A.; Romanova, V.M.; Sadowski, M.; Scholz, M.; Szydlowski, A.

    1999-01-01

    Argon-hydrogen mixture plasma focus experiments performed at the Warsaw Institute of Plasma Physics and Laser Microfusion show detailed space resolved spectra for Ar K-shell satellite lines up to F-like Ar and K-alpha of Ar. These transitions originating from autoionizing levels are caused by collisions of ions with the energetic electron beams which are created by the constrictions of the plasma column due to the development of magnetohydrodynamic instabilities. A collisional-radiative model was constructed using a non-Maxwellian electron energy distribution consisting of a thermal Maxwellian part plus a Gaussian part to represent the high-energy electron beam. The shapes of the observed satellite structures are consistent with the calculated spectrum for electron temperatures between 20 and 230 eV, and beam densities of about 10 -3 times the plasma electron density. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  12. Electron beam effects on the spectroscopy of multiply charged ions in plasma focus experiments

    Energy Technology Data Exchange (ETDEWEB)

    Abdallah, J. [UCLA Plasma Physics Laboratory, Los Angeles, CA (United States); Clark, R.E.H. [Los Alamos National Laboratory, Los Alamos, NM (United States); Faenov, A.Y. [MISDC, NPO ' VNIIFTRI' , Mendeleevo, Moscow region, 141570 (Russian Federation); Karpinski, L. [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Pikuz, S.A.; Romanova, V.M. [P. N. Lebedev Physical Institute, Moscow (Russian Federation); Sadowski, M. [Soltan Institute for Nuclear Studies, Swierk (Poland); Scholz, M.; Szydlowski, A. [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland)

    1999-05-01

    Argon-hydrogen mixture plasma focus experiments performed at the Warsaw Institute of Plasma Physics and Laser Microfusion show detailed space resolved spectra for Ar K-shell satellite lines up to F-like Ar and K-alpha of Ar. These transitions originating from autoionizing levels are caused by collisions of ions with the energetic electron beams which are created by the constrictions of the plasma column due to the development of magnetohydrodynamic instabilities. A collisional-radiative model wasconstructed using a non-Maxwellian electron energy distribution consisting of a thermal Maxwellian part plus a Gaussian part to represent the high-energy electron beam. The shapes of the observed satellite structures are consistent with the calculated spectrum for electron temperatures between 20 and 230 eV, and beam densities of about 10{sup -3} times the plasma electron density. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  13. Improving the resolution in soft X-ray emission spectrometers through photon-counting using an Electron Multiplying CCD

    International Nuclear Information System (INIS)

    Hall, D J; Soman, M; Tutt, J; Murray, N; Holland, A; Schmitt, T; Raabe, J; Strocov, V N; Schmitt, B

    2012-01-01

    In 2007, a study of back-illuminated Charge-Coupled Devices (CCDs) for soft X-ray photon detection demonstrated the improvements that could be brought over more traditional micro-channel plate detectors for X-ray spectrometers based on diffraction gratings and position sensitive detectors. Whilst the spatial resolution was reported to be improved dramatically, an intrinsic limit of approximately 25 micrometers was found due to the spreading of the charge cloud generated in the CCD across several pixels. To overcome this resolution limit, it is necessary to move away from the current integrated imaging methods and consider a photon-counting approach, recording the photon interaction locations to the sub-pixel level. To make use of photon-counting techniques it is important that the individual events are separable. To maintain the throughput of the spectrometer for high intensity lines, higher frame rates and therefore higher readout speeds are required. With CCD based systems, the increased noise at high readout speeds can limit the photon-counting performance. The Electron-Multiplying CCD shares a similar architecture with the standard CCD but incorporates a g ain register . This novel addition allows controllable gain to be applied to the signal before the read noise is introduced, therefore allowing individual events to be resolved above the noise even at much higher readout rates. In the past, the EM-CCD has only been available with imaging areas too small to be practical in soft X-ray emission spectrometers. The current drive for large area Electron-Multiplying CCDs is opening this technology to new photon-counting applications, requiring in-depth analysis of the processes and techniques involved. Early results indicate that through the introduction of photon-counting techniques the resolution in such systems can be dramatically improved.

  14. Detector system for particle or quantum radiation with a multitude of channel secondary electron multipliers arranged in the form of a laminar matrix

    Energy Technology Data Exchange (ETDEWEB)

    Manley, B W; Burgess, H

    1979-01-11

    The detector system may be used in diagnostic X-ray or gamma radiography. It essentially consists of a great number of channel secondary electron multipliers assigned to which are two electrodes consisting of parallel electrode strips each. The strips in one electrode are some distance away from those of the other electrode and are shifted by 90/sup 0/ with respect to them. Each electrode strip has got a connection joined to a charge detection circuit. This charge detection circuit contains a logic circuit by which a reliable assessment of the surface distribution of the particles resp. quanta hitting the channel secondary electron multipliers is made possible.

  15. Study of spatial resolution of coordinate detectors based on Gas Electron Multipliers

    Science.gov (United States)

    Kudryavtsev, V. N.; Maltsev, T. V.; Shekhtman, L. I.

    2017-02-01

    Spatial resolution of GEM-based tracking detectors is determined in the simulation and measured in the experiments. The simulation includes GEANT4 implemented transport of high energy electrons with careful accounting of atomic relaxation processes including emission of fluorescent photons and Auger electrons and custom post-processing with accounting of diffusion, gas amplification fluctuations, distribution of signals on readout electrodes, electronics noise and particular algorithm of final coordinate calculation (center of gravity). The simulation demonstrates that the minimum of spatial resolution of about 10 μm can be achieved with a gas mixture of Ar -CO2 (75-25 %) at a strips pitch from 250 μm to 300 μm. At a larger pitch the resolution quickly degrades reaching 80-100 μm at a pitch of 460-500 μm. Spatial resolution of low-material triple-GEM detectors for the DEUTERON facility at the VEPP-3 storage ring is measured at the extracted beam facility of the VEPP-4 M collider. One-coordinate resolution of the DEUTERON detector is measured with electron beam of 500 MeV, 1 GeV and 3.5 GeV energies. The determined value of spatial resolution varies in the range from approximately 35 μm to 50 μm for orthogonal tracks in the experiments.

  16. Electron capture and ionization in collisions of multiply charged ions with H(2s)

    International Nuclear Information System (INIS)

    Errea, L F; Guzman, F; Illescas, Clara; Mendez, L; Pons, B; Riera, A; Suarez, J

    2007-01-01

    We present total cross sections for electron capture and ionization in collisions of B 5+ and Ne 10+ with H(2s), calculated using two methods: the semiclassical close-coupling molecular formalism and the eikonal-CTMC method. We have evaluated partial cross sections for capture into excited n-levels, required in plasma diagnostics

  17. Simulation and Digitization of a Gas Electron Multiplier Detector Using Geant4 and an Object-Oriented Digitization Program

    Science.gov (United States)

    McMullen, Timothy; Liyanage, Nilanga; Xiong, Weizhi; Zhao, Zhiwen

    2017-01-01

    Our research has focused on simulating the response of a Gas Electron Multiplier (GEM) detector using computational methods. GEM detectors provide a cost effective solution for radiation detection in high rate environments. A detailed simulation of GEM detector response to radiation is essential for the successful adaption of these detectors to different applications. Using Geant4 Monte Carlo (GEMC), a wrapper around Geant4 which has been successfully used to simulate the Solenoidal Large Intensity Device (SoLID) at Jefferson Lab, we are developing a simulation of a GEM chamber similar to the detectors currently used in our lab. We are also refining an object-oriented digitization program, which translates energy deposition information from GEMC into electronic readout which resembles the readout from our physical detectors. We have run the simulation with beta particles produced by the simulated decay of a 90Sr source, as well as with a simulated bremsstrahlung spectrum. Comparing the simulation data with real GEM data taken under similar conditions is used to refine the simulation parameters. Comparisons between results from the simulations and results from detector tests will be presented.

  18. Effect of an electron beam generated in an X-pinch plasma on the structure of the K spectra of multiply charged ions

    International Nuclear Information System (INIS)

    Pikuz, S.A.; Shelkovenko, T.A.; Ramanova, V.M.; Abdallah, J. Jr.; Csanak, G.; Clark, R.E.H.; Faenov, A.Ya.; Skobelev, I.Yu.; Hammer, D.A.

    1997-01-01

    The first experimental studies of an electron beam generated in an X pinch on the XP machine (Cornell University, USA) and the BIN machine (P. N. Lebedev Physical Institute, Russian Academy of Sciences) are reported. It is shown that it is possible in an X pinch to isolate the effect of a plasma-generated electron beam on the multiply charged ion radiation. The intensities of the satellite lines corresponding to Li-, Be-, B-, and C-like ions are calculated for the Al spectrum on the basis of a collisional-radiative model with a non-Maxwellian electron distribution in the plasma. The effect of an electron beam on the multiply charged light ion radiation in an X-pinch plasma is demonstrated. Comparing our calculations with the experimental spectra, we conclude that the present model can be used to estimate the electron beam intensity

  19. Efficiency enhancements for MCP-based beta autoradiography imaging

    CERN Document Server

    Lees, J E

    2002-01-01

    We describe three approaches to increase the beta detection efficiency of microchannel plate detectors for biological beta autoradiography:(a)reversing the microchannel plate (MCP) bias polarity, changing the conventional high negative voltage on the input MCP to a grounded input, (b) a reduction in MCP pore size from 12.5 to 6 mu m, (c) using a CsI coating as an efficient secondary electron emitter. We also present our first measurements of double-tracer ( sup 3 H and sup 1 sup 4 C) imaging using pulse height analysis to distinguish between isotopes.

  20. Development of Gas Electron Multiplier(GEM) for digital radiographic system

    International Nuclear Information System (INIS)

    Moon, B. S.; Chung, C. E.; Lee, J. W.

    2000-04-01

    Two computer programs SHOWFIELD and IMAGEQUAL have been developed. SHOWFIELD is used to draw electric field lines for GEM detectors and IMAGEQUAL is used to study the spatial resolution of x-ray images. Various simulation runs have been carried out using EGS4 to study the characteristics of electrons generated by micro-channel plates and Ar, Xe gases. A prototype GEM detector was developed through this project. The GEM detector is composed of a pair of GEM plates, a micro-channel plate, readout circuit in a gas filled chamber. GEM plate were made in CERN to meet KAERI's design specification and the micro-channel plates were purchased from Proxitronic company

  1. Optimizing low-light microscopy with back-illuminated electron multiplying charge-coupled device: enhanced sensitivity, speed, and resolution.

    Science.gov (United States)

    Coates, Colin G; Denvir, Donal J; McHale, Noel G; Thornbury, Keith D; Hollywood, Mark A

    2004-01-01

    The back-illuminated electron multiplying charge-coupled device (EMCCD) camera is having a profound influence on the field of low-light dynamic cellular microscopy, combining highest possible photon collection efficiency with the ability to virtually eliminate the readout noise detection limit. We report here the use of this camera, in 512 x 512 frame-transfer chip format at 10-MHz pixel readout speed, in optimizing a demanding ultra-low-light intracellular calcium flux microscopy setup. The arrangement employed includes a spinning confocal Nipkow disk, which, while facilitating the need to both generate images at very rapid frame rates and minimize background photons, yields very weak signals. The challenge for the camera lies not just in detecting as many of these scarce photons as possible, but also in operating at a frame rate that meets the temporal resolution requirements of many low-light microscopy approaches, a particular demand of smooth muscle calcium flux microscopy. Results presented illustrate both the significant sensitivity improvement offered by this technology over the previous standard in ultra-low-light CCD detection, the GenIII+intensified charge-coupled device (ICCD), and also portray the advanced temporal and spatial resolution capabilities of the EMCCD. Copyright 2004 Society of Photo-Optical Instrumentation Engineers.

  2. Preliminary results of the Gas Electron Multiplier (GEM) as real-time beam monitor in hadron therapy

    Energy Technology Data Exchange (ETDEWEB)

    Aza, E., E-mail: eleni.aza@cern.ch [CERN, Geneva 23, 1211 Geneva (Switzerland); AUTH, Department of Physics, 54124 Thessaloniki (Greece); Ciocca, M. [Fondazione CNAO, Strada Campeggi 53, 27100 Pavia (Italy); Murtas, F. [CERN, Geneva 23, 1211 Geneva (Switzerland); LNF-INFN, Via Fermi 40, 00044 Frascati (Italy); Puddu, S. [CERN, Geneva 23, 1211 Geneva (Switzerland); AEC-LHEP, University of Bern, Sidlerstrasse 5, 3012 Bern (Switzerland); Pullia, M. [Fondazione CNAO, Strada Campeggi 53, 27100 Pavia (Italy); Silari, M. [CERN, Geneva 23, 1211 Geneva (Switzerland)

    2017-01-01

    The use of proton and carbon ion beams in cancer therapy (also known as hadron therapy) is progressively growing worldwide due to their improved dose distributions, sparing of healthy tissues and (for carbon ions) increased radiobiological effectiveness especially for radio-resistant tumours. Strict Quality Assurance (QA) protocols need to be followed for guaranteeing the clinical beam specifications. The aim of this study was to assess the performance of a gaseous detector based on the Gas Electron Multiplier (GEM) technology for measuring the beam spot dimensions and the homogeneity of the scanned irradiation field, which are daily QA tasks commonly performed using radiochromic films. Measurements performed at the National Centre for Oncological Hadron Therapy (CNAO) in Pavia (Italy) showed that the detector is able to monitor the 2D beam image on-line with a pad granularity of 2 mm and a response proportional to the number of delivered particles. The dose homogeneity was measured with low deviation from the results obtained with radiochromic films.

  3. Channel electron multiplier operated on a sounding rocket without a cryogenic vacuum pump from 120 to 80 km altitude

    Science.gov (United States)

    Dickson, Shannon; Gausa, Michael; Robertson, Scott; Sternovsky, Zoltan

    2013-04-01

    We demonstrate that a channel electron multiplier (CEM) can be operated on a sounding rocket in the pulse-counting mode from 120 km to 80 km altitude without the cryogenic evacuation used in the past. Evacuation of the CEM is provided only by aerodynamic flow around the rocket. This demonstration is motivated by the need for additional flights of mass spectrometers to clarify the fate of metallic compounds and ions ablated from micrometeorites and their possible role in the nucleation of noctilucent clouds. The CEMs were flown as guest instruments on two sounding rockets to the mesosphere. Modeling of the aerodynamic flow around the payload with Direct Simulation Monte-Carlo (DSMC) code showed that the pressure is reduced below ambient in the void behind (relative to the direction of motion) an aft-facing surface. An enclosure containing the CEM was placed forward of an aft-facing deck and a valve was opened during flight to expose the CEM to the aerodynamically evacuated region behind it. The CEM operated successfully from apogee down to ∼80 km. A Pirani gauge confirmed pressures reduced to as low as 20% of ambient with the extent of reduction dependent upon altitude and velocity. Additional DSMC simulations indicate that there are alternate payload designs with improved aerodynamic pumping for forward mounted instruments such as mass spectrometers.

  4. Mass spectrometric determination of magnesium isotopic ratios and its corrections for electron multiplier discrimination and mass fractionation

    International Nuclear Information System (INIS)

    Deng Zhongguo

    1989-01-01

    The mass spectrometric determination of magnesium isotopic ratios by the use of uranyl nitrate added to magnesium samples to act as a binding agent is reported. Prebaking empty filaments and preheating filaments with deposited magnesium samples on its surface in a vacuum are employed to reduce the Na signal from the thenium-ribbon. Methods for correcting magnesium isotopic ratios for electron multiplier discrimination and mass fractionation are described in detail. The results of the determination of natural magnesium isotopic ratios are 25 Mg/ 24 Mg = 0.12660 (1±0.01%) and 26 Mg/ 24 Mg = 0.13938 (1±0.10%). The magnesium isotopic ratios of rich - 26 Mg-2 sample and rich- 25 Mg-1 sample are 24 Mg/ 26 Mg = 0.003463 (1±0.2%), 25 Mg/ 26 Mg = 0.001656 (±0.2%) and 24 Mg/ 25 Mg = 0.006716 (1±0.2%), 26 Mg/ 25 Mg = 0.007264 (1±0.2%) respectively

  5. Test beam studies of Gas Electron Multiplier (GEM) detectors for the upgrade of CMS endcap muon system

    CERN Document Server

    Sharma, Ram Krishna

    2017-01-01

    The High Luminosity LHC (HL-LHC) will provide exceptional high instantaneous and integrated luminosity. The forward region $\\mid \\eta \\mid \\geq 1.5$ of the CMS detector will face extremely high particle rates in tens of $KHz/cm^{2}$ and hence it will affect the momentum resolution and longevity of the muon detectors. To overcome these issues the CMS collaboration has decided to install new large size rate capable Triple Gas Electron Multiplier (GEM) detectors in the forward region of CMS muon system. The first set of Triple GEM detectors will be installed in the GE1/1 region $(1.5 \\leq \\eta \\leq 2.2)$ of muon endcap during the LS2 of the LHC and the next one will be installed in the GE2/1 region $(1.6 \\leq \\eta \\leq 2.5)$, during the LS3. Towards this goal, full-size CMS Triple GEM prototype chambers have been fabricated and put under the test beam at the CERN SPS test beam facility. The GEM detectors were operated with two gas mixtures $Ar/CO_{2}$ (70/30) and $Ar/CO_{2}/CF_{4}$ (40/15/45). In 2014 and 2016, ...

  6. Muon Chamber Endcap Upgrade of the CMS Experiment with Gas Electron Multiplier (GEM) Detectors and their Performance

    CERN Document Server

    Gola, Mohit

    2017-01-01

    As the CERN LHC is heading towards a high luminosity phase a very high flux is expected in the endcaps of the CMS Detector. The presence of muons in collision events can be due to rare or new physics so it is important to maintain the high trigger efficiency of the CMS muon system. The CMS Collaboration has proposed to instrument the high-eta region (1.6 lt IetaI lt 2.2) of the muon endcaps with Gas Electron Multiplier (GEM) detectors, referred to as GE1/1 chambers, during the LS2. This technology will help in maintaining optimum trigger performance with maximum selection efficiency of muons even in a high flux environment. We describe plans for a Slice Test to installa few GE1/1 chambers covering 50 degrees in azimuthal angle within the CMS detector in 2017, with subsequent operation during the current Run 2 of the LHC. We show the performance of the GE1/1 chambers to be installed during the slice test, specifically GEM foil leakage currents, chamber gas volume integrity, high voltage circuit performanc...

  7. Multiplying Money

    Directory of Open Access Journals (Sweden)

    Garry Jacobs

    2013-05-01

    Full Text Available This article is not a comprehensive factual history of money as an economic instrument. It aims rather to present an essential psychological history of the power of money as a social organization or social technology. It explores the catalytic role of money in the development of society and its ever-increasing capacity for accomplishment in both economic and non-economic fields. This perspective focuses attention on the unutilized potential for harnessing the social power of money for promoting full employment, global development and human welfare. The title ‘multiplying money’ is intended to convey the idea that this untapped potential is exponential in nature. In order to recognize it, some fundamental misconceptions about the nature of money, how it is created and on what it is based need to be examined. This is the second article in a series.

  8. Limitation of secondary electron multiplier non-linearity on accurate U-Th isotopic determination by MC-ICP-MS

    Science.gov (United States)

    Shen, C.; Wu, C.; Gallet, S.; Cheng, H.; Edwards, R.; Hsieh, Y.; Lin, K.

    2008-12-01

    Contemporary multicollector-inductively coupled plasma mass spectrometry (MC-ICP-MS) with discrete dynode secondary electron multipliers (SEMs) can offer U-Th isotopic determinations with subpermil-permil- level precision in femtogram quantities. However, accurate isotopic measurement requires fully understanding SEM mass and intensity biases. In additional to dead-time effect, Richter et al (2001, Int. J. Mass Spectrom., 206, 105-127) reported a nonlinearity on SEMs produced by ETP and MasCom for count rates > 20 thousand counts per second (cps). We evaluated the possible biases for ion beams of 500- 1,600,000 cps on a latest MasCom SEM, SEV TE-Z/17, with more effective ion optical acceptance area (>50%) and better peak shape than previous models, used in a MC-ICP-MS, Thermo Fisher NEPTUNE. With the retarding potential quadruple lens (RPQ) turned off, ion beam intensity can be biased by only dead- time effect, which can be precisely corrected online or offline. With the RPQ on, two additional biases, an exponential-like increase of ion beam intensity from 100-100,000 s cps and an apparent dead-time effect (-2 to 2 ns) at high count rates, are observed. They are likely caused by the slightly defocused ions with a wide kinetic energy spread of ~5 eV, 10 times worse than that with thermal source, passing through the RPQ lens to the SEM, which is installed behind the focal plane. Fortunately, the two biases, which are stable during the daily measurements with the same settings of inlet system, source lenses, zoom optics, and RPQ, can be corrected effectively offline to earn accurate U-Th isotopic measurement.

  9. Lifetime of MCP-PMTs and other performance features

    Science.gov (United States)

    Lehmann, A.; Böhm, M.; Eyrich, W.; Miehling, D.; Pfaffinger, M.; Stelter, S.; Uhlig, F.; Ali, A.; Belias, A.; Dzhygadlo, R.; Gerhardt, A.; Götzen, K.; Kalicy, G.; Krebs, M.; Lehmann, D.; Nerling, F.; Patsyuk, M.; Peters, K.; Schepers, G.; Schmitt, L.; Schwarz, C.; Schwiening, J.; Traxler, M.; Düren, M.; Etzelmüller, E.; Föhl, K.; Hayrapetyan, A.; Kreutzfeld, K.; Merle, O.; Rieke, J.; Schmidt, M.; Wasem, T.; Achenbach, P.; Cardinali, M.; Hoek, M.; Lauth, W.; Schlimme, S.; Sfienti, C.; Thiel, M.

    2018-02-01

    The bar PANDA experiment at FAIR will use DIRC detectors for the separation of hadrons. The compactness of the bar PANDA detector requires the image planes of these detectors to be placed inside the magnetic field of the solenoid. Due to this and other boundary conditions MCP-PMTs were identified as the only suitable photon sensors. Until recently the major obstacle for an application of MCP-PMTs in high rate experiments like bar PANDA were serious aging problems which led to damage at the photo-cathode and a fast declining quantum efficiency as the integrated anode charge (IAC) increased. With new countermeasures against the aging, in particular due to the application of an atomic layer deposition (ALD) technique to coat the MCP pores, the lifetime of MCP-PMTs has meanwhile increased by a factor >50 which is fully sufficient for bar PANDA. The recent results of our long-term lifetime measurements are discussed. New 2-inch MCP-PMT prototypes from Hamamatsu show an encouraging behavior. However, the currently best performing MCP-PMT is a 2-inch PHOTONIS tube with two ALD-layers which reaches an IAC of >16 C/cm2 without any visible sign of aging. In the second part of these proceedings a new data acquisition system of the PADIWA/TRB type is presented which allows a quasi-parallel measurement of many MCP-PMT performance parameters. Especially unwanted effects like dark-count rate, crosstalk, ion after-pulsing, and recoil electrons can be studied in more detail than ever before. Exemplary results for these parameters are shown. The discussed DAQ system will be used for the comprehensive data quality checks of the MCP-PMTs being built into the DIRCs.

  10. Multiplying dimensions

    CERN Multimedia

    2013-01-01

    A few weeks ago, I had a vague notion of what TED was, and how it worked, but now I’m a confirmed fan. It was my privilege to host CERN’s first TEDx event last Friday, and I can honestly say that I can’t remember a time when I was exposed to so much brilliance in such a short time.   TEDxCERN was designed to give a platform to science. That’s why we called it Multiplying Dimensions – a nod towards the work we do here, while pointing to the broader importance of science in society. We had talks ranging from the most subtle pondering on the nature of consciousness to an eighteen year old researcher urging us to be patient, and to learn from our mistakes. We had musical interludes that included encounters between the choirs of local schools and will.i.am, between an Israeli pianist and an Iranian percussionist, and between Grand Opera and high humour. And although I opened the event by announcing it as a day off from physics, we had a quite brill...

  11. High signal-to-noise ratio sensing with Shack–Hartmann wavefront sensor based on auto gain control of electron multiplying CCD

    International Nuclear Information System (INIS)

    Zhu Zhao-Yi; Li Da-Yu; Hu Li-Fa; Mu Quan-Quan; Yang Cheng-Liang; Cao Zhao-Liang; Xuan Li

    2016-01-01

    High signal-to-noise ratio can be achieved with the electron multiplying charge-coupled-device (EMCCD) applied in the Shack–Hartmann wavefront sensor (S–H WFS) in adaptive optics (AO). However, when the brightness of the target changes in a large scale, the fixed electron multiplying (EM) gain will not be suited to the sensing limitation. Therefore an auto-gain-control method based on the brightness of light-spots array in S–H WFS is proposed in this paper. The control value is the average of the maximum signals of every light spot in an array, which has been demonstrated to be kept stable even under the influence of some noise and turbulence, and sensitive enough to the change of target brightness. A goal value is needed in the control process and it is predetermined based on the characters of EMCCD. Simulations and experiments have demonstrated that this auto-gain-control method is valid and robust, the sensing SNR reaches the maximum for the corresponding signal level, and especially is greatly improved for those dim targets from 6 to 4 magnitude in the visual band. (special topic)

  12. COINCIDENCES BETWEEN ELECTRONS AND TARGET IONS TO IDENTIFY CAPTURE CHANNELS IN COLLISIONS OF MULTIPLY CHARGED IONS ON GAS TARGETS

    NARCIS (Netherlands)

    POSTHUMUS, JH; MORGENSTERN, R

    1992-01-01

    We have investigated multielectron capture processes in collisions of Ar9+ on Ar by measuring the resulting Auger electrons in coincidence with charge-state-analyzed target ions. In this way it was possible to reconstruct partial electron energy spectra, each corresponding to a particular number of

  13. Charging of insulators by multiply-charged-ion impact probed by slowing down of fast binary-encounter electrons

    Science.gov (United States)

    de Filippo, E.; Lanzanó, G.; Amorini, F.; Cardella, G.; Geraci, E.; Grassi, L.; La Guidara, E.; Lombardo, I.; Politi, G.; Rizzo, F.; Russotto, P.; Volant, C.; Hagmann, S.; Rothard, H.

    2010-12-01

    The interaction of ion beams with insulators leads to charging-up phenomena, which at present are under investigation in connection with guiding phenomena in nanocapillaries with possible application in nanofocused beams. We studied the charging dynamics of insulating foil targets [Mylar, polypropylene (PP)] irradiated with swift ion beams (C, O, Ag, and Xe at 40, 23, 40, and 30 MeV/u, respectively) via the measurement of the slowing down of fast binary-encounter electrons. Also, sandwich targets (Mylar covered with a thin Au layer on both surfaces) and Mylar with Au on only one surface were used. Fast-electron spectra were measured by the time-of-flight method at the superconducting cyclotron of Laboratori Nazionali del Sud (LNS) Catania. The charge buildup leads to target-material-dependent potentials of the order of 6.0 kV for Mylar and 2.8 kV for PP. The sandwich targets, surprisingly, show the same behavior as the insulating targets, whereas a single Au layer on the electron and ion exit side strongly suppresses the charging phenomenon. The accumulated number of projectiles needed for charging up is inversely proportional to electronic energy loss. Thus, the charging up is directly related to emission of secondary electrons.

  14. Charging of insulators by multiply-charged-ion impact probed by slowing down of fast binary-encounter electrons

    International Nuclear Information System (INIS)

    De Filippo, E.; Lanzano, G.; Cardella, G.; Amorini, F.; Geraci, E.; Grassi, L.; Politi, G.; La Guidara, E.; Lombardo, I.; Rizzo, F.; Russotto, P.; Volant, C.; Hagmann, S.; Rothard, H.

    2010-01-01

    The interaction of ion beams with insulators leads to charging-up phenomena, which at present are under investigation in connection with guiding phenomena in nanocapillaries with possible application in nanofocused beams. We studied the charging dynamics of insulating foil targets [Mylar, polypropylene (PP)] irradiated with swift ion beams (C, O, Ag, and Xe at 40, 23, 40, and 30 MeV/u, respectively) via the measurement of the slowing down of fast binary-encounter electrons. Also, sandwich targets (Mylar covered with a thin Au layer on both surfaces) and Mylar with Au on only one surface were used. Fast-electron spectra were measured by the time-of-flight method at the superconducting cyclotron of Laboratori Nazionali del Sud (LNS) Catania. The charge buildup leads to target-material-dependent potentials of the order of 6.0 kV for Mylar and 2.8 kV for PP. The sandwich targets, surprisingly, show the same behavior as the insulating targets, whereas a single Au layer on the electron and ion exit side strongly suppresses the charging phenomenon. The accumulated number of projectiles needed for charging up is inversely proportional to electronic energy loss. Thus, the charging up is directly related to emission of secondary electrons.

  15. New gas electron-multiplier detectors for the endcap muon system of the CMS experiment at the high-luminosity LHC design and prototype performance

    CERN Document Server

    Gruchala, Marek Michal

    2016-01-01

    The high luminosity LHC will require new detectors in the CMS endcap muon system to suppress the trigger rate of background events, to maintain high trigger efficiency for low transverse momentum muons, to enhance the robustness of muon detection in the high-flux environment of the endcap, and to extend the geometrical acceptance. We report on the design and recent progress towards implementing a new system of large-area, triple-foil gas electron-multiplier (GEM) detectors that will be installed in the first three of five muon detector stations in each endcap, the first station being closest to the interaction point. The first station will extend the geometric acceptance in pseudo-rapidity to eta lt 3.0 from the current limit of eta lt 2.4. The second and third stations will enhance the performance in the range 1.6 lt eta lt 2.4. We describe the design of the chambers and readout electronics and report on the performance of prototype systems in tests with cosmic ray muons, high-energy particlebeams, a...

  16. Electron transfer from H2 and Ar to stored multiply charged argon ions produced by synchrotron radiation

    International Nuclear Information System (INIS)

    Kravis, S.D.; Church, D.A.; Johnson, B.M.; Meron, M.; Jones, K.W.; Levin, J.C.; Sellin, I.A.; Azuma, Y.; Berrah-Mansour, N.; Berry, H.G.; Druetta, M.

    1992-01-01

    The rate coefficients for electron transfer from Ar and H 2 to Ar q+ ions (3≤q≤6) have been measured using an ion-storage technique in a Penning ion trap. The ions were produced in the trap by K-shell photoionization of Ar atoms, using broadband synchrotron x-ray radiation. K-electron removal resulted in vacancy cascading, yielding a distribution of argon-ion charge states peaked near Ar 4+ . The stored ion gas had an initial temperature near 480 K. The basic data determining the rate coefficients k(Ar q+ ) are the storage time constants of each charge state in the trap, in the presence of a measured pressure of target gas. The results of the measurements (in units of 10 -9 cm 3 s -1 ) are k(Ar 3+ ,H 2 )=4.3(0.7), k(Ar 3+ ,Ar)=1.6(0.2), k(Ar 4+ ,H 2 )=5.2(0.6), k(Ar 4+ ,Ar)=2.5(0.3), k(Ar 5+ ,H 2 )=5.9(0.7), k(Ar 5+ ,Ar)=2.9(0.3), k(Ar 6+ ,H 2 )=8.5(1.2), and k(Ar 6+ ,Ar)=2.5(0.3)

  17. Data acquisition and online control system for new gas-electron multiplier detectors in the endcap muon system of the CMS experiment

    CERN Document Server

    Ruiz Alvarez, Jose David

    2016-01-01

    A new data acquisition and on-line control system is being developed for gas-electron multiplier (GEM) detectors which will be installed in the forward region (1.6 \\( < \\eta < \\) 2.2) of the CMS muon spectrometer during the 2nd long shutdown of the LHC, planned for the period 2018-2019. A prototype system employs the TOTEM VFAT2 ASIC that will eventually be replaced with the VFAT3 ASIC, under development. The front-end ASIC communicates over printed circuit lines with an intermediate on-detector board called the opto-hybrid. Data, trigger, and control information is transmitted via optical fiber between the opto-hybrid and an off-detector readout system using micro-TCA technology. On-line software, implemented in the CMS XDAQ framework, includes applications for latency and HV scans, and system management. We report on the operational status of the prototype system that has been tested using cosmic ray muons and extracted high-energy particle beams. This work is preparatory for the operation of a prot...

  18. A comparison using Faraday cups with 1013 Ω amplifiers and a secondary electron multiplier to measure Os isotopes by negative thermal ionization mass spectrometry.

    Science.gov (United States)

    Wang, Guiqin; Sun, Tiantian; Xu, Jifeng

    2017-10-15

    According to the Johnson-Nyquist noise equation, the value of electron noise is proportional to the square root of the resistor value. This relationship gives a theoretical improvement of 100 in the signal/noise ratio by going from 10 11 Ω to 10 13 Ω amplifiers for Faraday detection in thermal ionization mass spectrometry (TIMS). We measured Os isotopes using static Faraday cups with 10 13 Ω amplifiers in negative thermal ionization mass spectrometry (NTIMS) and compared the results with those obtained with 10 11 Ω amplifiers and by peak-hopping on a single secondary electron multiplier (SEM). We analysed large loads of Os (1 μg) at a range of intensities of 187 OsO 3 (0.02-10 mV) in addition to small loads of Os (5-500 pg) to compare the results of the three methods. Using 10 13 Ω amplifiers, the long-term reproducibility determined from Merck Os was 187 Os/ 188 Os = 0.1211 ± 0.0086 and 0.120229 ± 0.000034 at 0.02 mV and 10 mV of 187 OsO 3 intensities. Meanwhile, the analysed JMC Os loadings of 5 and 500 pg showed 187 Os/ 188 Os = 0.10669 ± 0.00036 and 0.106807 ± 0.000023. In comparison, the values measured by the SEM were 187 Os/ 188 Os = 0.10704 ± 0.00056 and 0.10690 ± 0.00013. All errors are in 2 standard deviation (SD). Both the accuracy and the precision determined using the 10 13 Ω amplifiers and the SEM are identical when the Os amounts are within 10-50 pg. However, the former analysis time can be shortened by approximately two-thirds. The SEM measurement is still the most precise method for Os amounts 50 pg. Copyright © 2017 John Wiley & Sons, Ltd.

  19. Calculated characteristics of multichannel photoelectron multipliers

    International Nuclear Information System (INIS)

    Vasil'chenko, V.G.; Dajkovskij, A.G.; Milova, N.V.; Rakhmatov, V.E.; Rykalin, V.I.

    1990-01-01

    Structural features and main calculated characteristics of some modifications of position-sensitive two-coordinate multichannel photoelectron multipliers (PEM) with plate-type multiplying systems are described. The presented PEM structures are free from direct optical and ion feedbacks, provide coordinate resolution ≅ 1 mm with efficiency of photoelectron detection ≅ 90%. Capabilities for using silicon field-effect photocathodes, providing electron extraction into vacuum, as well as prospects of using multichannel multiplying systems for readout of the data from solid detectors are considered

  20. Electron multiplier for the measurement of an ion current on a mass spectrometer; Multiplicateur d'electrons pour la mesure de courant d'ions sur un spectrometre de masse

    Energy Technology Data Exchange (ETDEWEB)

    Lohez, P; Nief, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1957-07-01

    The apparatus described is designed to measure weak ion currents received at the collector of a mass spectrometer. The report describes successively the study of electron paths in the multiplier by the method of analogy, using rubber membranes, and the practical details of construction of the apparatus. The variation with surface treatment of the secondary emission coefficient of the alloy CuBe containing 2 per cent Be, which makes up the dynodes, and the influence of the voltage on the gain per stage, are discussed. Results of tests regarding: the influence of the ion mass on the gain, the background of the instrument and the energy distribution of the impulses coming out on a high gain multiplier (q.q. 10{sup 7}) are given. Finally the performances of the multiplier are reported. 1- For a low gain (10{sup 4}), precision and reproducibility comparable to the electrometer valve, sensitivity 100 times greater, currents capable of detection 10{sup -17} Ampere. 2- For a high gain (10{sup 7}) and measurement by impulse counting, currents capable of detection 10{sup -19} Ampere. Mounting difficult to use on a mass spectrometer. (author) [French] L'appareil decrit est destine a la mesure des faibles courants d'ions re s au collecteur d'un spectrometre de masse. Le rapport decrit successivement l'etude des trajectoires des electrons dans le multiplicateur, par la methode analogique de la menbrane en caoutchouc, et la realisation pratique de l'appareil. La variation du coefficient d'emission secondaire de l'alliage CuBe a 2 pour cent de Be, constituant les dynodes suivant le traitement des surfaces, et l'influence de la tension sur le gain par etage sont discutees. Des resultats d'essais concernant: l'influence de la masse des ions sur le gain, le bruit de fond de l'appareil et la repartition en energie des impulsions de sortie sur un multiplicateur a gain eleve (q.q. 10{sup 7}) sont donnes. Enfin, sont rapportees les performances du multiplicateur. 1- pour un gain faible

  1. Combined effects of 1-methyl cyclopropene (1-MCP) and modified ...

    African Journals Online (AJOL)

    1-MCP-treated fruits delayed two different harvest maturity, persimmon fruits flesh firmness, and combination of 1-MCP with MAPA and MAPB reduced the ethylene production rate during storage. Treatment of 1-MCP improved storability of persimmon fruits more effectively than MAP storage. However, the results indicated ...

  2. The Multiply Handicapped Child.

    Science.gov (United States)

    Wolf, James M., Ed.; Anderson, Robert M., Ed.

    Articles presented in the area of the medical and educational challenge of the multiply handicapped child are an overview of the problem, the increasing challenge, congenital malformations, children whose mothers had rubella, prematurity and deafness, the epidemiology of reproductive casualty, and new education for old problems. Discussions of…

  3. The Multiplier Effect.

    Science.gov (United States)

    Flowers, William L., Jr.; Harris, John B.

    1981-01-01

    The multiplier effect is discussed as it applies to the field of continuing education. The authors' main point is that one grant or contract can, and should, be used as the basis for building organizational competencies and capabilities that will secure other funds. (Author/CT)

  4. Microwave Frequency Multiplier

    Science.gov (United States)

    Velazco, J. E.

    2017-02-01

    High-power microwave radiation is used in the Deep Space Network (DSN) and Goldstone Solar System Radar (GSSR) for uplink communications with spacecraft and for monitoring asteroids and space debris, respectively. Intense X-band (7.1 to 8.6 GHz) microwave signals are produced for these applications via klystron and traveling-wave microwave vacuum tubes. In order to achieve higher data rate communications with spacecraft, the DSN is planning to gradually furnish several of its deep space stations with uplink systems that employ Ka-band (34-GHz) radiation. Also, the next generation of planetary radar, such as Ka-Band Objects Observation and Monitoring (KaBOOM), is considering frequencies in the Ka-band range (34 to 36 GHz) in order to achieve higher target resolution. Current commercial Ka-band sources are limited to power levels that range from hundreds of watts up to a kilowatt and, at the high-power end, tend to suffer from poor reliability. In either case, there is a clear need for stable Ka-band sources that can produce kilowatts of power with high reliability. In this article, we present a new concept for high-power, high-frequency generation (including Ka-band) that we refer to as the microwave frequency multiplier (MFM). The MFM is a two-cavity vacuum tube concept where low-frequency (2 to 8 GHz) power is fed into the input cavity to modulate and accelerate an electron beam. In the second cavity, the modulated electron beam excites and amplifies high-power microwaves at a frequency that is a multiple integer of the input cavity's frequency. Frequency multiplication factors in the 4 to 10 range are being considered for the current application, although higher multiplication factors are feasible. This novel beam-wave interaction allows the MFM to produce high-power, high-frequency radiation with high efficiency. A key feature of the MFM is that it uses significantly larger cavities than its klystron counterparts, thus greatly reducing power density and arcing

  5. Fiscal Multipliers in Ukraine

    OpenAIRE

    Pritha Mitra; Tigran Poghosyan

    2015-01-01

    Amid renewed crisis, falling tax revenues, and rising debt, Ukraine faces serious fiscal consolidation needs. Durable fiscal adjustment can support economic confidence and rebuild buffers but what is its overall impact on growth? How effective are revenue versus spending instruments? Does current or capital spending have a larger impact? Applying a structural vector autoregressive model, this paper finds that Ukraine’s near-term revenue and spending multipliers are well below one. In the medi...

  6. Why Multiply by "g"?

    Science.gov (United States)

    Nelson, Jane Bray

    2012-01-01

    As a new physics teacher, I was explaining how to find the weight of an object sitting on a table near the surface of the Earth. It bothered me when a student asked, "The object is not accelerating so why do you multiply the mass of the object by the acceleration due to gravity?" I answered something like, "That's true, but if the table were not…

  7. Coincident detection of electrons ejected at large angles and target recoil ions produced in multiply ionizing collisions for the 1-MeV/u Oq++Ar collision system

    International Nuclear Information System (INIS)

    Gaither III, C.C.; Breinig, M.; Berryman, J.W.; Hasson, B.F.; Richards, J.D.; Price, K.

    1993-01-01

    The angular distributions of energetic electrons ejected at angles between 45 degree and 135 degree with respect to the incident-beam direction have been measured in coincidence with the charge states of the target recoil ions produced in multiply ionizing collisions for the 1-MeV/u O q+ (q=4,7)+Ar collision systems. These measurements have been made for ∼179-, ∼345-, and ∼505-eV electrons. Additionally, the energy distributions of electrons ejected into specific angular regions have been measured. Ar LMM satellite Auger electrons appear as a peak in the energy spectrum of electrons ejected at all large angles. The center of this peak is found at an electron energy of ∼179 eV. Electrons with ∼179 eV energy, ejected at large angles, are preferentially produced in coincidence with recoil ions of charge state 4+. Electrons with ∼345 eV energy and ∼505 eV energy ejected at large angles are preferentially produced in coincidence with recoil ions of charge state 3+. The angular distributions for these electrons are strongly peaked in the forward direction; essentially no electrons are observed at angles larger than 90 degree. These results are consistent with the dominant production mechanism for energetic electrons ejected at large angles being a binary-encounter process. Differential cross sections have been calculated from these angular distributions. They are on the order of 10 -21 cm 2 /(eV sr)

  8. Optical studies of multiply excited states

    International Nuclear Information System (INIS)

    Mannervik, S.

    1989-01-01

    Optical studies of multiply-excited states are reviewed with emphasis on emission spectroscopy. From optical measurements, properties such as excitation energies, lifetimes and autoionization widths can be determined with high accuracy, which constitutes a challenge for modern computational methods. This article mainly covers work on two-, three- and four-electron systems, but also sodium-like quartet systems. Furthermore, some comments are given on bound multiply-excited states in negative ions. Fine structure effects on transition wavelengths and lifetimes (autoionization) are discussed. In particular, the most recent experimental and theoretical studies of multiply-excited states are covered. Some remaining problems, which require further attention, are discussed in more detail. (orig.) With 228 refs

  9. Single ion counting with a MCP (microchannel plate) detector

    Energy Technology Data Exchange (ETDEWEB)

    Tawara, Hiroko; Sasaki, Shinichi; Miyajima, Mitsuhiro [National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan); Shibamura, Eido

    1996-07-01

    In this study, a single-ion-counting method using alpha-particle-impact ionization of Ar atoms is demonstrated and the preliminary {epsilon}{sub mcp} for Ar ions with incident energies of 3 to 4.7 keV is determined. The single-ion counting by the MCP is aimed to be performed under experimental conditions as follows: (1) A signal from the MCP is reasonably identified as incidence of single Ar-ion. (2) The counting rate of Ar ions is less than 1 s{sup -1}. (3) The incident Ar ions are not focused on a small part of an active area of the MCP, namely, {epsilon}{sub mcp} is determined with respect to the whole active area of the MCP. So far, any absolute detection efficiency has not been reported under these conditions. (J.P.N.)

  10. Characterizations of MCP performance in the hard x-ray range (6–25 keV)

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Ming, E-mail: minwu@sandia.gov; Rochau, Greg [Sandia National Laboratory, Albuquerque, New Mexico 87185 (United States); Moy, Ken [Special Technology Laboratories, NSTec, Santa Barbara, California 93111-2335 (United States); Kruschwitz, Craig [National Security Technologies, LLC, Los Alamos Operations, Los Alamos, New Mexico 87544 (United States)

    2014-11-15

    MCP detector performance at hard x-ray energies from 6 to 25 keV was recently investigated using NSLS beamline X15A at BNL. Measurements were made with an NSTec Gen-II (H-CA-65) framing camera, based on a Photonis MCP with ∼10 μm in diameter pores, ∼12 μm center-center spacing, an L/D ratio of 46, and a bias angle of 8°. The MCP characterizations were focused on (1) energy and angle dependent sensitivity, (2) energy and angle dependent spatial resolution, (3) energy dependent gain performance, and (4) energy dependent dynamic range. These measurement corroborated simulation results using a Monte Carlo model that included hard x-ray interactions and the subsequent electron cascade in the MCP.

  11. Electron-impact excitation of multiply-charged ions using energy loss in merged beams: e + Si3+(3s2S1/2) → e + Si3+(3p2P1/2,3/2)

    International Nuclear Information System (INIS)

    Wahlin, E.K.; Thompson, J.S.; Dunn, G.H.; Phaneuf, R.A.; Gregory, D.C.; Smith, A.C.H.

    1990-01-01

    For the first time absolute total cross sections for electron-impact excitation of a multiply-charged ion have been measured using an electron-energy-loss technique. Measurements were made near threshold for the process e + Si 3+ (3s 2 S 1/2 ) → e + Si 3+ (3p 2 P 1/2 , 3/2 ) -- 8.88 eV. The 10 -15 cm 2 measured cross section agrees with results of 7-state close coupling calculations to better than the ±20% (90% CL) total uncertainty of the measurements. Convoluting the theoretical curve with a Gaussian energy distribution indicates an energy width of 0.15 approx-lt ΔE approx-lt 0.20 eV. 12 refs., 2 figs

  12. MCP characterization at the Cu and Mo Kα x-ray energies

    International Nuclear Information System (INIS)

    Walsh, P.J.; Evans, S.; Schappert, G.T.; Kyrala, G.A.

    1998-03-01

    The authors are investigating the usefulness of microchannel plate (MCP) intensifiers for imaging x-rays at high photon energies, specifically by using filtered X-rays from an electron bombardment source to generate the K α lines of Cu at 8.04 KeV and Mo at 17.5 KeV. These high energy lines are used to measure the resolution of an MCP based intensifier produced at Los Alamos National Laboratory. They have investigated the spot size of a fielded MCP intensifier by observing, on film, the result of single photon excitation of microchannels. Measurement of the spot size was done with visible light microscopy. They report initial results of the spot size distribution in the stripline direction. They have also begun a measurement of the azimuthal anisotropy in the spatial resolution, accentuated at these energies by the inclination of the axis of the MCP channels. They concentrate on an actual ''fielded instrument'' resolution, rather than ideal, for the purpose of analyzing image data captured at the NOVA Laser Facility

  13. Systemic MCP1/CCR2 blockade and leukocyte specific MCP1/CCR2 inhibition affect aortic aneurysm formation differently

    NARCIS (Netherlands)

    de Waard, Vivian; Bot, Ilze; de Jager, Saskia C. A.; Talib, Sara; Egashira, Kensuke; de Vries, Margreet R.; Quax, Paul H. A.; Biessen, Erik A. L.; van Berkel, Theo J. C.

    2010-01-01

    Objective: CCR2, the receptor for monocyte chemoattractant protein 1 (MCP1), is involved in atherosclerosis and abdominal aortic aneurysms (AAAs). Here, we explored the potential beneficial blockade of the MCP1/CCR2 pathway. Methods: We applied an AAA model in aging apolipoprotein E deficient mice

  14. UWB delay and multiply receiver

    Energy Technology Data Exchange (ETDEWEB)

    Dallum, Gregory E.; Pratt, Garth C.; Haugen, Peter C.; Romero, Carlos E.

    2013-09-10

    An ultra-wideband (UWB) delay and multiply receiver is formed of a receive antenna; a variable gain attenuator connected to the receive antenna; a signal splitter connected to the variable gain attenuator; a multiplier having one input connected to an undelayed signal from the signal splitter and another input connected to a delayed signal from the signal splitter, the delay between the splitter signals being equal to the spacing between pulses from a transmitter whose pulses are being received by the receive antenna; a peak detection circuit connected to the output of the multiplier and connected to the variable gain attenuator to control the variable gain attenuator to maintain a constant amplitude output from the multiplier; and a digital output circuit connected to the output of the multiplier.

  15. Optimization design of a 20-in. elliptical MCP-PMT

    International Nuclear Information System (INIS)

    Chen, Ping; Tian, Jinshou; Wei, Yonglin; Liu, Hulin; Sai, Xiaofeng; He, Jianping; Chen, Lin; Wang, Xing; Lu, Yu

    2017-01-01

    This paper describes the simulation work for optimizing the newly developed 20-in. elliptical MCP-PMT by enlarging the outside diameters of the two focusing electrodes and the open area of the glass bulb. Effects of biasing voltages applied to the two focusing electrodes and the MCP input facet are studied. With the new design of the 20 in. MCP-PMT, the transit time spread of the prototype can be less than 3 ns and the collection efficiency is as much as the present prototype.

  16. Development and tests of MCP based timing and multiplicity detector for MIPs

    Science.gov (United States)

    Feofilov, G.; Kondratev, V.; Stolyarov, O.; Tulina, T.; Valiev, F.; Vinogradov, L.

    2017-01-01

    We present summary of technological developments and tests of the MCP based large area detector aimed at precise timing and charged particles multiplicity measurements. Results obtained in course of these developments of isochronous (simultaneity) precise signal readout, passive summation of 1 ns signals, fast (1 GHz) front-end electronics, miniature vacuum systems, etc. could be potentially interesting for a number of future applications in different fields.

  17. Transmission-Line Readout with Good Time and Space Resolutions for Planacon MCP-PMTs

    CERN Document Server

    Tang, F; Byrum, K; Drake, G; Ertley, C; Frisch, H; Genat, J-F; May, E

    2008-01-01

    With commercially-available multi-anode microchannel plate photomultiplier tubes (MCP-PMT) and electronics, resolutions significantly better than 10 psec have been achieved in small systems with a few readout channels[1,2]. For large-scale time-of-flight systems used in particle physics, which may cover tens of square meters, a solution must be found with a manageable number of electronics channels and low total power consumption on the readout electronics without degrading the system timing resolution. We present here the design of a transmission-line readout for a Photonis Planacon MCP-PMT that has these characteristics. The tube, which is 5 cm square, is characterized by signal pulse rise times in the order of 200 psec and transit time spreads (TTS) in the order of 25 psec[1, 2]. The model 85011-011 MCP has 1024 anode pads laid out in an array of 32 by 32 on the back of the tube. The proposed readout is implemented on a Rogers 4350B printed circuit board with 32 parallel 50-ohm transmission lines on 1.6 mm...

  18. The CLIC Test Facility (CTF3) which allowed the first electron beam recombination in order to multiply the RF frequency from 3 GHz up to 15 GHz.

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    Photo 0210005_11: The CTF3 linac accelerates an electron beam up to 350 MeV. Photo 0210005_1: At the front, the yellow dipole is used for the spectrometer line. At the back, a doublet of blue quadrupole for the matching. Photo 0210005_03: The CTF3 transfer line between the electron linac and the isochronous ring. Photo 0210005_04: One arc of the EPA isochronous ring. Photo 0210005_06: The CTF3 bunching system. The first RF wave guide feeds the Pre-Buncher while the second RF wave guide feeds the Buncher. They provide a bunched electron beam at 4 MeV. The blue magnet is a solenoid around the Buncher. Photo 0210005_07: A LIL accelerating structure used for CTF3. It is 4.5 meters long and provides an energy gain of 45 MeV. One can see 3 quadrupoles around the RF structure.

  19. Effect of 1-methylcyclopropene (1- MCP) treatment on antioxidant ...

    African Journals Online (AJOL)

    ajl2

    2013-02-13

    Feb 13, 2013 ... of active oxygen-related metabolism of post-harvest Japanese apricot. The results ... a high content of vitamin C (ascorbic acid) and retarding the decrease ..... components analysis of the nfluence of 1-MCP and salicylic acid.

  20. Effects of Triptergium Glycosides on Expressions of MCP- 1 and ...

    African Journals Online (AJOL)

    the pathogenesis of diabetic nephropathy (DN), which is one of the chronic ..... the release of lysosomal enzymes and TGF, increase the ... important roles in the pathogenesis of this disease. Thus, MCP-1 and CTGF are potential targets for ...

  1. Effective switching frequency multiplier inverter

    Science.gov (United States)

    Su, Gui-Jia [Oak Ridge, TN; Peng, Fang Z [Okemos, MI

    2007-08-07

    A switching frequency multiplier inverter for low inductance machines that uses parallel connection of switches and each switch is independently controlled according to a pulse width modulation scheme. The effective switching frequency is multiplied by the number of switches connected in parallel while each individual switch operates within its limit of switching frequency. This technique can also be used for other power converters such as DC/DC, AC/DC converters.

  2. CCL2/MCP-1 modulation of microglial activation and proliferation

    Directory of Open Access Journals (Sweden)

    Garcia-Bueno Borja

    2011-07-01

    Full Text Available Abstract Background Monocyte chemoattractant protein (CCL2/MCP-1 is a chemokine that attracts cells involved in the immune/inflammatory response. As microglia are one of the main cell types sustaining inflammation in brain, we proposed here to analyze the direct effects of MCP-1 on cultured primary microglia. Methods Primary microglia and neuronal cultures were obtained from neonatal and embryonic Wistar rats, respectively. Microglia were incubated with different concentrations of recombinant MCP-1 and LPS. Cell proliferation was quantified by measuring incorporation of bromodeoxyuridine (BrdU. Nitrite accumulation was measured using the Griess assay. The expression and synthesis of different proteins was measured by RT-PCR and ELISA. Cell death was quantified by measuring release of LDH into the culture medium. Results MCP-1 treatment (50 ng/ml, 24 h did not induce morphological changes in microglial cultures. Protein and mRNA levels of different cytokines were measured, showing that MCP-1 was not able to induce proinflammatory cytokines (IL-1β, IL6, MIP-1α, either by itself or in combination with LPS. A similar lack of effect was observed when measuring inducible nitric oxide synthase (NOS2 expression or accumulation of nitrites in the culture media as a different indicator of microglial activation. MCP-1 was also unable to alter the expression of different trophic factors that were reduced by LPS treatment. In order to explore the possible release of other products by microglia and their potential neurotoxicity, neurons were co-cultured with microglia: no death of neurons could be detected when treated with MCP-1. However, the presence of MCP-1 induced proliferation of microglia, an effect opposite to that observed with LPS. Conclusion These data indicate that, while causing migration and proliferation of microglia, MCP-1 does not appear to directly activate an inflammatory response in this cell type, and therefore, other factors may be

  3. Study on MCP-1 related to inflammation induced by biomaterials

    International Nuclear Information System (INIS)

    Ding Tingting; Sun Jiao; Zhang Ping

    2009-01-01

    The study of inflammation is important for understanding the reaction between biomaterials and the human body, in particular, the interaction between biomaterials and immune system. In the current study, rat macrophages were induced by multiple biomaterials with different biocompatibilities, including polyvinyl chloride (PVC) containing 8% of organic tin, a positive control material with cellular toxicity. Human umbilical vein endothelial cells (ECV-304), cultured with PRMI-1640, were detached from cells cultured with the supernatant of macrophages containing TNF-α and IL-1β because of stimulation by biomaterials. The cells were then treated with different biomaterials. Then both TNF-α and IL-1β in macrophages were detected by ELISA. Levels of monocyte chemoattractant protein-1 (MCP-1) were measured by RT-PCR. The results suggested that the expression of TNF-α and IL-1β was elevated by polytetrafluoroethylene (PTFE), polylactic-co-glycolic acid (PLGA) and American NPG alloy (p < 0.001). The level of MCP-1 cultured in supernatant of macrophages was higher than in PRMI-1640 with the same biomaterials. And the exposure to PTFE, PLGA and NPG resulted in the high expression of MCP-1 (p < 0.001) following cytokine stimulation. MCP-1 was also significantly expressed in β-tricalcium phosphate (β-TCP) and calcium phosphate cement samples (CPC) (p < 0.01). Thus, TNF-α, IL-1β and MCP-1 had played an important role in the immune reaction induced by biomaterials and there was a close relationship between the expression of cytokines and biomcompatibility of biomaterials. Furthermore, these data suggested that MCP-1 was regulated by TNF-α and IL-1β, and activated by both cytokines and biomaterials. The data further suggested that the expression of MCP-1 could be used as a marker to indicate the degree of immune reaction induced by biomaterials.

  4. A Synthesis of Star Calibration Techniques for Ground-Based Narrowband Electron-Multiplying Charge-Coupled Device Imagers Used in Auroral Photometry

    Science.gov (United States)

    Grubbs, Guy II; Michell, Robert; Samara, Marilia; Hampton, Don; Jahn, Jorg-Micha

    2016-01-01

    A technique is presented for the periodic and systematic calibration of ground-based optical imagers. It is important to have a common system of units (Rayleighs or photon flux) for cross comparison as well as self-comparison over time. With the advancement in technology, the sensitivity of these imagers has improved so that stars can be used for more precise calibration. Background subtraction, flat fielding, star mapping, and other common techniques are combined in deriving a calibration technique appropriate for a variety of ground-based imager installations. Spectral (4278, 5577, and 8446 A ) ground-based imager data with multiple fields of view (19, 47, and 180 deg) are processed and calibrated using the techniques developed. The calibration techniques applied result in intensity measurements in agreement between different imagers using identical spectral filtering, and the intensity at each wavelength observed is within the expected range of auroral measurements. The application of these star calibration techniques, which convert raw imager counts into units of photon flux, makes it possible to do quantitative photometry. The computed photon fluxes, in units of Rayleighs, can be used for the absolute photometry between instruments or as input parameters for auroral electron transport models.

  5. Lagrange multipliers and gravitational theory

    International Nuclear Information System (INIS)

    Elston, F.D.

    1977-01-01

    The Lagrange multiplier variational method is extended to nonlinear Lagrangians in a Riemann space, where it is shown explicitly for the quadratic Lagrangians that, as expected, this approach is equivalent to the Hilbert variational method. It is not, in general, equivalent to the Palatini variational method. The nonvanishing Lagrange multipliers for the quadratic Lagrangians are explicitly obtained in covariant form. A similiar analysis is then carried out in a Riemann--Cartan torsional metric space for the specific Lagrangians g/sup 1/2/R tilde and g/sup 1/2/R/sub uv/tilde R/sup uv/tilde. The possible relevance of the R/sub uv/R/sup u anti v/ invariant to an action-principle formulation of the Rainich--Misner--Wheeler (RMW) already-unified theory is also discussed. It is then pointed out how a different use of the Lagrange multiplier technique in the language of the 3 + 1 canonical formalism developed by Arnowitt, Deser, and Misner (ADM) permits the recasting of the equations of motion for quadratic and general higher-order invariants into the ADM canonical formalism. In general, without this Lagrange multiplier approach, the higher-order ADM problem could not be solved. This is done explicitly for the simplest quadratic Langrangian g/sup 1/2/R 2 as an example

  6. Multiplied Environmental Literacy. Final Report.

    Science.gov (United States)

    Buethe, Chris

    This booklet presents a pupil-oriented program designed to increase the environmental literacy of teachers and students in Indiana schools through a programmed multiplier effect. Junior and senior high school science teachers were prepared to teach students the meanings of 44 selected environmental terms and related concepts. Those teachers then…

  7. MCP1 haplotypes associated with protection from pulmonary tuberculosis

    Directory of Open Access Journals (Sweden)

    Owusu-Dabo Ellis

    2011-04-01

    Full Text Available Abstract Background The monocyte chemoattractant protein 1 (MCP-1 is involved in the recruitment of lymphocytes and monocytes and their migration to sites of injury and cellular immune reactions. In a Ghanaian tuberculosis (TB case-control study group, associations of the MCP1 -362C and the MCP1 -2581G alleles with resistance to TB were recently described. The latter association was in contrast to genetic effects previously described in study groups originating from Mexico, Korea, Peru and Zambia. This inconsistency prompted us to further investigate the MCP1 gene in order to determine causal variants or haplotypes genetically and functionally. Results A 14 base-pair deletion in the first MCP1 intron, int1del554-567, was strongly associated with protection against pulmonary TB (OR = 0.84, CI 0.77-0.92, Pcorrected = 0.00098. Compared to the wildtype combination, a haplotype comprising the -2581G and -362C promoter variants and the intronic deletion conferred an even stronger protection than did the -362C variant alone (OR = 0.78, CI 0.69-0.87, Pnominal = 0.00002; adjusted Pglobal = 0.0028. In a luciferase reporter gene assay, a significant reduction of luciferase gene expression was observed in the two constructs carrying the MCP1 mutations -2581 A or G plus the combination -362C and int1del554-567 compared to the wildtype haplotype (P = 0.02 and P = 0.006. The associated variants, in particular the haplotypes composed of these latter variants, result in decreased MCP-1 expression and a decreased risk of pulmonary TB. Conclusions In addition to the results of the previous study of the Ghanaian TB case-control sample, we have now identified the haplotype combination -2581G/-362C/int1del554-567 that mediates considerably stronger protection than does the MCP1 -362C allele alone (OR = 0.78, CI 0.69-0.87 vs OR = 0.83, CI 0.76-0.91. Our findings in both the genetic analysis and the reporter gene study further indicate a largely negligible role of the

  8. Principal parameters of classical multiply charged ion sources

    International Nuclear Information System (INIS)

    Winter, H.; Wolf, B.H.

    1974-01-01

    A review is given of the operational principles of classical multiply charged ion sources (operating sources for intense beams of multiply charged ions using discharge plasmas; MCIS). The fractional rates of creation of multiply charged ions in MCIS plasmas cannot be deduced from the discharge parameters in a simple manner; they depend essentially on three principal parameters, the density and energy distribution of the ionizing electrons, and the confinement time of ions in the ionization space. Simple discharge models were used to find relations between principal parameters, and results of model calculations are compared to actually measured charge state density distributions of extracted ions. Details of processes which determine the energy distribution of ionizing electrons (heating effects), confinement times of ions (instabilities), and some technical aspects of classical MCIS (cathodes, surface processes, conditioning, life time) are discussed

  9. Quality management of cut carnation 'Tempo' with 1- MCP

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... carnation 'Tempo' which is an ethylene-sensitive flower, were evaluated. The effects of 1-MCP .... rolling of the petals. Water uptake rate (ml g-1 .... The studies of Chamani (2006) on Rosa 'First red' cut flowers revealed that ...

  10. Quality management of cut carnation 'Tempo' with 1- MCP | Abadi ...

    African Journals Online (AJOL)

    Quality management of cut carnation 'Tempo' with 1- MCP. ... African Journal of Biotechnology ... time durations (3, 6 and 9 h) on the vaselife, water uptake, loss of fresh weight and chlorophyll index of cut carnation 'Tempo' which is an ...

  11. VIDA COMERCIAL DE PITAHAYA AMARILLA TRATADA CON 1-MCP

    Directory of Open Access Journals (Sweden)

    LILIANA SERNA-COCK

    Full Text Available 1-metilciclopropeno (1-MCP, un inhibidor del etileno, ha sido utilizado para extender la vida comercial de diferentes frutas. El objetivo de este trabajo fue evaluar el efecto de la aplicación de soluciones acuosas de 10, 100 y 200 gL-1 de 1-MCP, con tiempos de exposición de 1, 5 y 10 minutos, sobre la vida comercial de pitahaya amarilla en estado de madurez 4. Durante 15 días de almacenamiento (25 ± 2°C y 75% de humedad relativa, se evaluaron cambios físicos como la pérdida de peso y la aparición de pardeamiento; y se midieron cambios químicos como sólidos solubles, pH, acidez e índice de madurez. Se presentaron diferencias significativas entre los tratamientos. Los resultados demostraron que aplicaciones de 200 gL-1 de 1-MCP durante 10 minutos prolongó por tres días, la vida comercial de la pitahaya amarilla, y redujo cambios en los sólidos solubles y la acidez

  12. The MCP-4/MCP-1 ratio in plasma is a candidate circadian biomarker for chronic post-traumatic stress disorder

    Science.gov (United States)

    Dalgard, C; Eidelman, O; Jozwik, C; Olsen, C H; Srivastava, M; Biswas, R; Eudy, Y; Rothwell, S W; Mueller, G P; Yuan, P; Drevets, W C; Manji, H K; Vythlingam, M; Charney, D S; Neumeister, A; Ursano, R J; Jacobowitz, D M; Pollard, H B; Bonne, O

    2017-01-01

    Post-traumatic stress disorder (PTSD) is psychiatric disease, which can occur following exposure to traumatic events. PTSD may be acute or chronic, and can have a waxing and waning course of symptoms. It has been hypothesized that proinflammatory cytokines and chemokines in the cerebrospinal fluid (CSF) or plasma might be mediators of the psychophysiological mechanisms relating a history of trauma exposure to changes in behavior and mental health disorders, and medical morbidity. Here we test the cytokine/chemokine hypothesis for PTSD by examining levels of 17 classical cytokines and chemokines in CSF, sampled at 0900 hours, and in plasma sampled hourly for 24 h. The PTSD and healthy control patients are from the NIMH Chronic PTSD and healthy control cohort, initially described by Bonne et al. (2011), in which the PTSD patients have relatively low comorbidity for major depressive disorder (MDD), drug or alcohol use. We find that in plasma, but not CSF, the bivariate MCP4 (CCL13)/ MCP1(CCL2) ratio is ca. twofold elevated in PTSD patients compared with healthy controls. The MCP-4/MCP-1 ratio is invariant over circadian time, and is independent of gender, body mass index or the age at which the trauma was suffered. By contrast, MIP-1β is a candidate biomarker for PTSD only in females, whereas TARC is a candidate biomarker for PTSD only in males. It remains to be discovered whether these disease-specific differences in circadian expression for these specific immune signaling molecules are biomarkers, surrogates, or drivers for PTSD, or whether any of these analytes could contribute to therapy. PMID:28170001

  13. Development of MCP transient operation strategy for the SMART-P

    International Nuclear Information System (INIS)

    Yoo, S. E.; Choi, B. S.; Kang, H. O.; Yoon, J. H.; Ji, S. K.

    2003-01-01

    SMART-P MCP(Main Coolant Pump) transient operation strategies are developed. A Modular Modeling System (MMS) computer code is used for the evaluation of the developed operation strategies. In the SMART-P, normal operating modes are classified into MCP high speed(3600 rpm) mode and MCP low speed mode. Also, natural circulation mode is defined as a performance test case. MCP operation transients occur when changing modes from one to another, and system parameters(core power, system pressure, temperature) are having transients. These transients affect on system performance and, in some cases, limit system operation. In this study, MCP operation strategies are developed and obtained acceptable results

  14. Synthesis algorithm of VLSI multipliers for ASIC

    Science.gov (United States)

    Chua, O. H.; Eldin, A. G.

    1993-01-01

    Multipliers are critical sub-blocks in ASIC design, especially for digital signal processing and communications applications. A flexible multiplier synthesis tool is developed which is capable of generating multiplier blocks for word size in the range of 4 to 256 bits. A comparison of existing multiplier algorithms is made in terms of speed, silicon area, and suitability for automated synthesis and verification of its VLSI implementation. The algorithm divides the range of supported word sizes into sub-ranges and provides each sub-range with a specific multiplier architecture for optimal speed and area. The algorithm of the synthesis tool and the multiplier architectures are presented. Circuit implementation and the automated synthesis methodology are discussed.

  15. MCP-1, ICAM-1 and VCAM-1 are present in early aneurysmal dilatation in experimental rats

    International Nuclear Information System (INIS)

    Jun Fan; Hao-Tong; Jing Di; Fang Liu; Hai-Hua Zhao; Shu-Ling Bai; Xiang Li; Linlin Zhong

    2010-01-01

    Recent studies have suggested that inflammation actively participates in ascending aortic aneurysm formation. The aim of the present study was to evaluate the expression changes of adhesion molecules and MMPs in an experimental model of ascending aortic aneurysm induced by ascending aorta banding in Wistar rats. Twelve rats developed aortic dilation after ascending aorta banding treatment, while nine normal animals underwent surgery without banding were used as controls. Light microscope and scanning electron microscope showed that the wall of the ascending aorta became disorganized as well as infiltration by inflammatory cells in aneurysmal rats. By using immunohistochemical techniques, a significant increase in the immunostaining of MCP-1 was observed in the aneurysmal wall as compared to the normal aortic wall. Under similar experimental conditions, we also found that the immunostaining of ICAM-1 and VCAM-1 was markedly increased in the aneurysmal wall. In addition, gelatin zymo graphic analysis showed that the expression and activities of MMP-2 and MMP-9 were remarkably enhanced in the ascending aorta of ascending aortic aneurysmal rats as compared to normal rats. These results demonstrate that MCP-1, ICAM-1 and VCAM-1 are involved in the pathogenesis of ascending aortic aneurysm and an increase in the immunostaining and activity of MMP-2 and MMP-9 may promote the progression of ascending aortic aneurysm. (authors)

  16. MCP-1 expressed by osteoclasts stimulates osteoclastogenesis in an autocrine/paracrine manner

    International Nuclear Information System (INIS)

    Miyamoto, Kana; Ninomiya, Ken; Sonoda, Koh-Hei; Miyauchi, Yoshiteru; Hoshi, Hiroko; Iwasaki, Ryotaro; Miyamoto, Hiroya

    2009-01-01

    Monocyte chemoattractant protein-1 (MCP-1) is a chemokine that plays a critical role in the recruitment and activation of leukocytes. Here, we describe that multinuclear osteoclast formation was significantly inhibited in cells derived from MCP-1-deficient mice. MCP-1 has been implicated in the regulation of osteoclast cell-cell fusion; however defects of multinuclear osteoclast formation in the cells from mice deficient in DC-STAMP, a seven transmembrane receptor essential for osteoclast cell-cell fusion, was not rescued by recombinant MCP-1. The lack of MCP-1 in osteoclasts resulted in a down-regulation of DC-STAMP, NFATc1, and cathepsin K, all of which were highly expressed in normal osteoclasts, suggesting that osteoclast differentiation was inhibited in MCP-1-deficient cells. MCP-1 alone did not induce osteoclastogenesis, however, the inhibition of osteoclastogenesis in MCP-1-deficient cells was restored by addition of recombinant MCP-1, indicating that osteoclastogenesis was regulated in an autocrine/paracrine manner by MCP-1 under the stimulation of RANKL in osteoclasts.

  17. Otanps synapse linear relation multiplier circuit

    International Nuclear Information System (INIS)

    Chible, H.

    2008-01-01

    In this paper, a four quadrant VLSI analog multiplier will be proposed, in order to be used in the implementation of the neurons and synapses modules of the artificial neural networks. The main characteristics of this multiplier are the small silicon area and the low power consumption and the high value of the weight input voltage. (author)

  18. On compact multipliers of topological algebras

    International Nuclear Information System (INIS)

    Mohammad, N.

    1994-08-01

    It is shown that if the maximal ideal space Δ(A) of a semisimple commutative complete metrizable locally convex algebra contains no isolated points, then every compact multiplier is trivial. Particularly, compact multipliers on semisimple commutative Frechet algebras whose maximal ideal space has no isolated points are identically zero. (author). 5 refs

  19. Faster and Energy-Efficient Signed Multipliers

    Directory of Open Access Journals (Sweden)

    B. Ramkumar

    2013-01-01

    Full Text Available We demonstrate faster and energy-efficient column compression multiplication with very small area overheads by using a combination of two techniques: partition of the partial products into two parts for independent parallel column compression and acceleration of the final addition using new hybrid adder structures proposed here. Based on the proposed techniques, 8-b, 16-b, 32-b, and 64-b Wallace (W, Dadda (D, and HPM (H reduction tree based Baugh-Wooley multipliers are developed and compared with the regular W, D, H based Baugh-Wooley multipliers. The performances of the proposed multipliers are analyzed by evaluating the delay, area, and power, with 65 nm process technologies on interconnect and layout using industry standard design and layout tools. The result analysis shows that the 64-bit proposed multipliers are as much as 29%, 27%, and 21% faster than the regular W, D, H based Baugh-Wooley multipliers, respectively, with a maximum of only 2.4% power overhead. Also, the power-delay products (energy consumption of the proposed 16-b, 32-b, and 64-b multipliers are significantly lower than those of the regular Baugh-Wooley multiplier. Applicability of the proposed techniques to the Booth-Encoded multipliers is also discussed.

  20. Temperature Insensitive Current-Mode Four Quadrant Multiplier Using Single CFCTA

    Directory of Open Access Journals (Sweden)

    Tuntrakool Sunti

    2017-01-01

    Full Text Available A four quadrant multiplier of two current input signals using active building block, namely current follower cascaded transconductance amplifier (CFCTA is presented in this paper. The proposed multiplier consists of only single CFCTA without the use of any passive element. The presented circuit has low impedance at current input node and high impedance at current output node which is convenient for cascading in current mode circuit without the need of current buffer circuits. The output current can multiply two input currents with temperature insensitivity. Moreover, the magnitude of output current can be controlled electronically via DC bias current. With only single active building block, the presented multiplier is suitable for integrated circuit implementation for analog signal processing. Simulation results from a PSpice program are presented in order to demonstrate the multiplier proposed here.

  1. Modular Engine Noise Component Prediction System (MCP) Program Users' Guide

    Science.gov (United States)

    Golub, Robert A. (Technical Monitor); Herkes, William H.; Reed, David H.

    2004-01-01

    This is a user's manual for Modular Engine Noise Component Prediction System (MCP). This computer code allows the user to predict turbofan engine noise estimates. The program is based on an empirical procedure that has evolved over many years at The Boeing Company. The data used to develop the procedure include both full-scale engine data and small-scale model data, and include testing done by Boeing, by the engine manufacturers, and by NASA. In order to generate a noise estimate, the user specifies the appropriate engine properties (including both geometry and performance parameters), the microphone locations, the atmospheric conditions, and certain data processing options. The version of the program described here allows the user to predict three components: inlet-radiated fan noise, aft-radiated fan noise, and jet noise. MCP predicts one-third octave band noise levels over the frequency range of 50 to 10,000 Hertz. It also calculates overall sound pressure levels and certain subjective noise metrics (e.g., perceived noise levels).

  2. Multiply-negatively charged aluminium clusters and fullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Noelle

    2008-07-15

    Multiply negatively charged aluminium clusters and fullerenes were generated in a Penning trap using the 'electron-bath' technique. Aluminium monoanions were generated using a laser vaporisation source. After this, two-, three- and four-times negatively charged aluminium clusters were generated for the first time. This research marks the first observation of tetra-anionic metal clusters in the gas phase. Additionally, doubly-negatively charged fullerenes were generated. The smallest fullerene dianion observed contained 70 atoms. (orig.)

  3. Associations between Deceased-Donor Urine MCP-1 and Kidney Transplant Outcomes.

    Science.gov (United States)

    Mansour, S G; Puthumana, J; Reese, P P; Hall, I E; Doshi, M D; Weng, F L; Schröppel, B; Thiessen-Philbrook, H; Bimali, M; Parikh, C R

    2017-07-01

    Existing methods to predict recipient allograft function during deceased-donor kidney procurement are imprecise. Understanding the potential renal reparative role for monocyte chemoattractant protein-1 (MCP-1), a cytokine involved in macrophage recruitment after injury, might help predict allograft outcomes. We conducted a sub-study of the multicenter prospective Deceased Donor Study cohort, which evaluated deceased kidney donors from five organ procurement organizations from May 2010 to December 2013. We measured urine MCP-1 (uMCP-1) concentrations from donor samples collected at nephrectomy to determine associations with donor acute kidney injury (AKI), recipient delayed graft function (DGF), 6-month estimated GFR (eGFR), and graft failure. We also assessed perfusate MCP-1 concentrations from pumped kidneys for associations with DGF and 6-month eGFR. AKI occurred in 111 (9%) donors. Median (interquartile range) uMCP-1 concentration was higher in donors with AKI compared to donors without AKI (1.35 [0.41-3.93] ng/ml vs. 0.32 [0.11-0.80] ng/ml, p<0.001). DGF occurred in 756 (31%) recipients, but uMCP-1 was not independently associated with DGF. Higher donor uMCP-1 concentrations were independently associated with higher 6-month eGFR in those without DGF [0.77 (0.10, 1.45) ml/min/1.73m 2 per doubling of uMCP1]. However, there were no independent associations between uMCP-1 and graft failure over a median follow-up of about 2 years. Lastly, perfusate MCP-1 concentrations significantly increased during pump perfusion but were not associated with DGF or 6-month eGFR. Donor uMCP-1 concentrations were modestly associated with higher recipient 6-month eGFR in those without DGF. However, the results suggest that donor uMCP-1 has minimal clinical utility given no associations with graft failure.

  4. Keynesian multiplier versus velocity of money

    Science.gov (United States)

    Wang, Yougui; Xu, Yan; Liu, Li

    2010-08-01

    In this paper we present the relation between Keynesian multiplier and the velocity of money circulation in a money exchange model. For this purpose we modify the original exchange model by constructing the interrelation between income and expenditure. The random exchange yields an agent's income, which along with the amount of money he processed determines his expenditure. In this interactive process, both the circulation of money and Keynesian multiplier effect can be formulated. The equilibrium values of Keynesian multiplier are demonstrated to be closely related to the velocity of money. Thus the impacts of macroeconomic policies on aggregate income can be understood by concentrating solely on the variations of money circulation.

  5. Two micron pore size MCP-based image intensifiers

    Science.gov (United States)

    Glesener, John; Estrera, Joseph

    2010-02-01

    Image intensifiers (I2) have many advantages as detectors. They offer single photon sensitivity in an imaging format, they're light in weight and analog I2 systems can operate for hours on a single AA battery. Their light output is such as to exploit the peak in color sensitivity of the human eye. Until recent developments in CMOS sensors, they also were one of the highest resolution sensors available. The closest all solid state solution, the Texas Instruments Impactron chip, comes in a 1 megapixel format. Depending on the level of integration, an Impactron based system can consume 20 to 40 watts in a system configuration. In further investing in I2 technology, L-3 EOS determined that increasing I2 resolution merited a high priority. Increased I2 resolution offers the system user two desirable options: 1) increased detection and identification ranges while maintaining field-of-view (FOV) or 2) increasing FOV while maintaining the original system resolution. One of the areas where an investment in resolution is being made is in the microchannel plate (MCP). Incorporation of a 2 micron MCP into an image tube has the potential of increasing the system resolution of currently fielded systems. Both inverting and non-inverting configurations are being evaluated. Inverting tubes are being characterized in night vision goggle (NVG) and sights. The non-inverting 2 micron tube is being characterized for high resolution I2CMOS camera applications. Preliminary measurements show an increase in the MTF over a standard 5 micron pore size, 6 micron pitch plate. Current results will be presented.

  6. Multipliers for continuous frames in Hilbert spaces

    International Nuclear Information System (INIS)

    Balazs, P; Bayer, D; Rahimi, A

    2012-01-01

    In this paper, we examine the general theory of continuous frame multipliers in Hilbert space. These operators are a generalization of the widely used notion of (discrete) frame multipliers. Well-known examples include anti-Wick operators, STFT multipliers or Calderón–Toeplitz operators. Due to the possible peculiarities of the underlying measure spaces, continuous frames do not behave quite as their discrete counterparts. Nonetheless, many results similar to the discrete case are proven for continuous frame multipliers as well, for instance compactness and Schatten-class properties. Furthermore, the concepts of controlled and weighted frames are transferred to the continuous setting. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Coherent states: mathematical and physical aspects’. (paper)

  7. Economic Multipliers and Mega-Event Analysis

    OpenAIRE

    Victor Matheson

    2004-01-01

    Critics of economic impact studies that purport to show that mega-events such as the Olympics bring large benefits to the communities “lucky” enough to host them frequently cite the use of inappropriate multipliers as a primary reason why these impact studies overstate the true economic gains to the hosts of these events. This brief paper shows in a numerical example how mega-events may lead to inflated multipliers and exaggerated claims of economic benefits.

  8. Charge-exchange collisions of multiply charged ions with atoms

    International Nuclear Information System (INIS)

    Grozdanov, T.P.; Janev, R.K.

    1978-01-01

    The problem of electron transfer between neutral atoms and multiply charged ions is considered at low and medium energies. It is assumed that a large number of final states are available for the electron transition so that the electron-capture process is treated as a tunnel effect caused by the strong attractive Coulomb field of the multicharged ions. The electron transition probability is obtained in a closed form using the modified-comparison-equation method to solve the Schroedinger equation. An approximately linear dependence of the one-electron transfer cross section on the charge of multicharged ion is found. Cross-section calculations of a number of charge-exchange reactions are performed

  9. The chemokine MCP-1 (CCL2) in the host interaction with cancer: a foe or ally?

    Science.gov (United States)

    Yoshimura, Teizo

    2018-01-29

    Macrophages are one of the most abundant leukocyte populations infiltrating tumor tissues and can exhibit both tumoricidal and tumor-promoting activities. In 1989, we reported the purification of monocyte chemoattractant protein-1 (MCP-1) from culture supernatants of mitogen-activated peripheral blood mononuclear cells and tumor cells. MCP-1 is a potent monocyte-attracting chemokine, identical to the previously described lymphocyte-derived chemotactic factor or tumor-derived chemotactic factor, and greatly contributes to the recruitment of blood monocytes into sites of inflammatory responses and tumors. Because in vitro-cultured tumor cells often produce significant amounts of MCP-1, tumor cells are considered to be the main source of MCP-1. However, various non-tumor cells in the tumor stroma also produce MCP-1 in response to stimuli. Studies performed in vitro and in vivo have provided evidence that MCP-1 production in tumors is a consequence of complex interactions between tumor cells and non-tumor cells and that both tumor cells and non-tumor cells contribute to the production of MCP-1. Although MCP-1 production was once considered to be a part of host defense against tumors, it is now believed to regulate the vicious cycle between tumor cells and macrophages that promotes the progression of tumors.Cellular and Molecular Immunology advance online publication, 29 January 2018; doi:10.1038/cmi.2017.135.

  10. Associations Between Deceased-Donor Urine MCP-1 and Kidney Transplant Outcomes

    Directory of Open Access Journals (Sweden)

    S.G. Mansour

    2017-07-01

    Discussion: Donor uMCP-1 concentrations were modestly associated with higher recipient 6-month eGFR in those without DGF. However, the results suggest that donor uMCP-1 has minimal clinical utility given no associations with graft failure.

  11. Circulating MCP-1 level and вˆј2518 gene polymorphism as a ...

    African Journals Online (AJOL)

    Azza M. Hassan

    that plays an important role in the recruitment of monocytes/macrophages into renal tubulointer- stitium. A biallelic A/G polymorphism at position 2518 in the MCP-1 gene was found ..... minurea, but also with UAE in their type 2 diabetic patients. This is explained by the pivotal role played by increased MCP-. 1 production due ...

  12. Monocyte chemoattractant protein 1 (MCP-1) in temporal arteritis and polymyalgia rheumatica

    DEFF Research Database (Denmark)

    Ellingsen, T; Elling, P; Olson, A

    2000-01-01

    was localised to the vessel wall in patients with TA. In TA, PMR, and healthy controls MCP-1 was quantified by enzyme linked immunosorbent assay (ELISA) in plasma. RESULTS: MCP-1 was localised to the majority of mononuclear cells, some smooth muscle cells, and giant cells in the arterial biopsy specimens from...

  13. Study of the effects of 1-MCP to blueberry under cold storage

    Science.gov (United States)

    Tao, Shenchen; Chu, Huailiang; Chen, Xiaomin; Yuan, Huwei; Qiu, Lingling; Zhao, Liang; Yan, Daoliang; Zheng, Bingsong

    2017-04-01

    Blueberry is one of the thinnest exocarp fruits in the world, which is difficult to keep fresh due to the special structure of its skin. 1-Methlcyclopropene (1-MCP) is able to combine with ethylene(ETH) receptor. In this study we investigated the effect of 1-MCP on rotting rate, weight loss ratio, soluble sugar content, titratable acid content, antioxidant enzyme activities and malondialdehyde (MDA) content in blueberry (Vaccinium corymbosun ‘O Neal’ and ‘North Road’) under cold storage. 1-MCP reduced the rotting rate, weight loss ratio and MDA content, while keeping high-leveled stability in antioxidant enzyme activities, soluble sugar content and titratable acid content. These results showed the role of 1-MCP in alleviating the negative effects of blueberry and suggested that 1-MCP could be used as a preservative for keeping thin exocarp fruit in fresh.

  14. Batch production of microchannel plate photo-multipliers

    Energy Technology Data Exchange (ETDEWEB)

    Frisch, Henry J.; Wetstein, Matthew; Elagin, Andrey

    2018-03-06

    In-situ methods for the batch fabrication of flat-panel micro-channel plate (MCP) photomultiplier tube (PMT) detectors (MCP-PMTs), without transporting either the window or the detector assembly inside a vacuum vessel are provided. The method allows for the synthesis of a reflection-mode photocathode on the entrance to the pores of a first MCP or the synthesis of a transmission-mode photocathode on the vacuum side of a photodetector entrance window.

  15. Increased MCP-1 gene expression in monocytes of severe OSA patients and under intermittent hypoxia.

    Science.gov (United States)

    Chuang, Li-Pang; Chen, Ning-Hung; Lin, Yuling; Ko, Wen-Shan; Pang, Jong-Hwei S

    2016-03-01

    Obstructive sleep apnea (OSA) is known to be a risk factor of coronary artery disease. Monocyte chemoattractant protein-1 (MCP-1), as a critical factor for monocyte infiltration, is known to play a role in the development of atherosclerosis. This study aimed to investigate the effect of intermittent hypoxia, the hallmark of OSA, on the MCP-1 expression of monocytes. Peripheral blood was sampled from 61 adults enrolled for suspected OSA. RNA was prepared from the isolated monocytes for the analysis of MCP-1. The effect of in vitro intermittent hypoxia on the regulation and function of MCP-1 was investigated on THP-1 monocytic cells and human monocytes. The mRNA and secreted protein levels were investigated by RT/real-time PCR and enzyme-linked immunosorbent assay, respectively. Monocytic MCP-1 gene expression was found to be increased significantly in severe OSA patients. In vitro intermittent hypoxia was demonstrated to increase the mRNA and protein expression levels of MCP-1 dose- and time-dependently in THP-1 monocytic cells. The MCP-1 mRNA expression in monocytes isolated from OSA patient was induced to a much higher level compared to that from normal control. Pre-treatment with inhibitor for p42/44 MAPK or p38 MAPK suppressed the activation of MCP-1 expression by intermittent hypoxia. This is the first study to demonstrate the increase of MCP-1 gene expression in monocytes of severe OSA patients. In addition, monocytic MCP-1 gene expression can be induced under intermittent hypoxia.

  16. Bio/Nano Electronic Devices and Sensors

    National Research Council Canada - National Science Library

    Jones, W. K

    2008-01-01

    ...) Cold cathode microwave generator and ceramic electron multiplier-ceramic multiplier using a novel secondary electron yield materials of MgO and CNT was demonstrated as well as cooling structures...

  17. How to prevent ripening blockage in 1-MCP-treated 'Conference' pears.

    Science.gov (United States)

    Chiriboga, Maria-Angeles; Schotsmans, Wendy C; Larrigaudière, Christian; Dupille, Eve; Recasens, Inmaculada

    2011-08-15

    Some European pear varieties treated with 1-methylcyclopropene (1-MCP) often remain 'evergreen', meaning that their ripening process is blocked and does not resume after removal from cold storage. In this work this was confirmed also to be the case in 'Conference' pears. To reverse the blockage of ripening 1-MCP treatments combined with external exogenous ethylene were tested. 1-MCP treatment of 'Conference' pears is very effective in delaying ripening and, more specifically, softening. The same 1-MCP concentration in different experimental years caused a different response. The higher dose of 1-MCP (600 nL L⁻¹) always resulted in irreversible blockage of ripening, whereas the behaviour of fruit receiving a lower dose (300 nL L⁻¹) depended on the year, and this did not depend on maturity at harvest or on storage conditions. Simultaneous exposure to 1-MCP and exogenous ethylene significantly affected fruit ripening, allowing significant softening to occur but at a lower rate compared with control fruit. The application of exogenous ethylene and 1-MCP simultaneously after harvest permitted restoration of the ripening process after storage in 'Conference' pears, extending the possibility of marketing and consumption. Copyright © 2011 Society of Chemical Industry.

  18. Development of a secondary electron energy analyzer for a transmission electron microscope.

    Science.gov (United States)

    Magara, Hideyuki; Tomita, Takeshi; Kondo, Yukihito; Sato, Takafumi; Akase, Zentaro; Shindo, Daisuke

    2018-04-01

    A secondary electron (SE) energy analyzer was developed for a transmission electron microscope. The analyzer comprises a microchannel plate (MCP) for detecting electrons, a coil for collecting SEs emitted from the specimen, a tube for reducing the number of backscattered electrons incident on the MCP, and a retarding mesh for selecting the energy of SEs incident on the MCP. The detection of the SEs associated with charging phenomena around a charged specimen was attempted by performing electron holography and SE spectroscopy using the energy analyzer. The results suggest that it is possible to obtain the energy spectra of SEs using the analyzer and the charging states of a specimen by electron holography simultaneously.

  19. IP-10, MCP-1, MCP-2, MCP-3, and IL-1RA hold promise as biomarkers for infection with M. tuberculosis in a whole blood based T-cell assay

    DEFF Research Database (Denmark)

    Ruhwald, Morten; Bjerregaard-Andersen, Morten; Rabna, Paulo

    2009-01-01

    and mitogen in the Quantiferon In Tube test tubes. Levels of biomarkers were measured using Luminex and ELISA (IFN-gamma). RESULTS: We found all five new biomarkers were expressed in significantly higher concentrations compared to IFN-gamma. IP-10 and MCP-3 levels in the un-stimulated samples were higher...

  20. Semigroups of Herz-Schur multipliers

    DEFF Research Database (Denmark)

    Knudby, Søren

    2014-01-01

    function (see Theorem 1.2). It is then shown that a (not necessarily proper) generator of a semigroup of Herz–Schur multipliers splits into a positive definite kernel and a conditionally negative definite kernel. We also show that the generator has a particularly pleasant form if and only if the group...

  1. A quantum architecture for multiplying signed integers

    International Nuclear Information System (INIS)

    Alvarez-Sanchez, J J; Alvarez-Bravo, J V; Nieto, L M

    2008-01-01

    A new quantum architecture for multiplying signed integers is presented based on Booth's algorithm, which is well known in classical computation. It is shown how a quantum binary chain might be encoded by its flank changes, giving the final product in 2's-complement representation.

  2. Relationships between serum MCP-1 and subclinical kidney disease: African American-Diabetes Heart Study

    Directory of Open Access Journals (Sweden)

    Murea Mariana

    2012-11-01

    Full Text Available Abstract Background Monocyte chemoattractant protein-1 (MCP-1 plays important roles in kidney disease susceptibility and atherogenesis in experimental models. Relationships between serum MCP-1 concentration and early nephropathy and subclinical cardiovascular disease (CVD were assessed in African Americans (AAs with type 2 diabetes (T2D. Methods Serum MCP-1 concentration, urine albumin:creatinine ratio (ACR, estimated glomerular filtration rate (eGFR, and atherosclerotic calcified plaque (CP in the coronary and carotid arteries and infrarenal aorta were measured in 479 unrelated AAs with T2D. Generalized linear models were fitted to test for associations between MCP-1 and urine ACR, eGFR, and CP. Results Participants were 57% female, with mean ± SD (median age 55.6±9.5 (55.0 years, diabetes duration 10.3±8.2 (8.0 years, urine ACR 149.7±566.7 (14.0 mg/g, CKD-EPI eGFR 92.4±23.3 (92.0 ml/min/1.73m2, MCP-1 262.9±239.1 (224.4 pg/ml, coronary artery CP 280.1±633.8 (13.5, carotid artery CP 47.1±132.9 (0, and aorta CP 1616.0±2864.0 (319.0. Adjusting for age, sex, smoking, HbA1c, BMI, and LDL, serum MCP-1 was positively associated with albuminuria (parameter estimate 0.0021, P=0.04 and negatively associated with eGFR (parameter estimate −0.0003, P=0.001. MCP-1 remained associated with eGFR after adjustment for urine ACR. MCP-1 levels did not correlate with the extent of CP in any vascular bed, HbA1c or diabetes duration, but were positively associated with BMI. No interaction between BMI and MCP-1 was detected on nephropathy outcomes. Conclusions Serum MCP-1 levels are associated with eGFR and albuminuria in AAs with T2D. MCP-1 was not associated with subclinical CVD in this population. Inflammation appears to play important roles in development and/or progression of kidney disease in AAs.

  3. MCP-1 in urine as biomarker of disease activity in Systemic Lupus Erythematosus.

    Science.gov (United States)

    Barbado, Julia; Martin, Debora; Vega, Luisa; Almansa, Raquel; Gonçalves, Lisbeth; Nocito, Mercedes; Jimeno, Antonio; Ortiz de Lejarazu, Raúl; Bermejo-Martin, Jesus F

    2012-11-01

    Conventional clinical parameters are not sensitive or specific enough for detecting ongoing disease activity in the Systemic Lupus Erythematosus (SLE). Measurement of cytokines in urine is an encouraging approach to detection of early flares in this disease. Here we have profiled 27 different cytokines, chemokines and celular growth factors in the urine of 48 patients previously diagnosed of SLE as potential biomarkers of disease activity. Correlation analysis with Bonferroni correction showed that MCP-1 was the only immune mediator which levels in urine correlated directly with the SLE Disease Activity Index 2000 (SLEDAI-2K) score (correlation coefficient, p): MCP-1 (0.45,0.003). MCP-1 correlated inversely with levels of C3 complement protein in serum (-0.50,0.001). MCP-1 showed significant higher levels in patients with severe disease activity in comparison with those exhibiting mild activity. Levels of this chemokine were also higher in patients with severe disease activity in comparison with patients with inactive disease and healthy controls. Areas under receiver operating characteristic curves (AUROC) for detection of severe disease (SLEDAI⩾8) was as follows for MCP-1: [AUROC, (IC95%), p]: [0.81 (0.65-0.96) 0.003]. In addition, MCP-1 showed a good result in the AUROC analysis for detecting renal involvement [0.70 (0.52-0.87) 0.050]. When correlation analysis were repeated excluding those patients with active renal disease (n=14), levels of MCP-1 in urine kept on showing a significant positive association with SLEDAI-2K score. In conclusion, multiplex-based cytokine profiling in urine demonstrated the superiority of MCP-1 over a wide range of cytokines as biomarker of disease activity in SLE. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. 1-MCP pretreatment prevents bud and flower abscission in Dendrobium orchids

    NARCIS (Netherlands)

    Uthaichay, N.; Ketsa, S.; Doorn, van W.G.

    2007-01-01

    Dendrobium orchid inflorescences were treated for 4 h at 25 °C with or without 100¿500 nl/l 1-MCP and were then placed in water at 25 °C to follow abscission. In controls, depending on the experiment, 20¿80% of the floral buds and 0¿20% of the open flowers abscised within 1 week. The 1-MCP

  5. MicroCameras and Photometers (MCP) on board the TARANIS satellite

    Science.gov (United States)

    Farges, T.; Hébert, P.; Le Mer-Dachard, F.; Ravel, K.; Gaillac, S.

    2017-12-01

    TARANIS (Tool for the Analysis of Radiations from lightNing and Sprites) is a CNES micro satellite. Its main objective is to study impulsive transfers of energy between the Earth atmosphere and the space environment. It will be sun-synchronous at an altitude of 700 km. It will be launched in 2019 for at least 2 years. Its payload is composed of several electromagnetic instruments in different wavelengths (from gamma-rays to radio waves including optical). TARANIS instruments are currently in calibration and qualification phase. The purpose is to present the MicroCameras and Photometers (MCP) design, to show its performances after its recent characterization and at last to discuss the scientific objectives and how we want to answer it with the MCP observations. The MicroCameras, developed by Sodern, are dedicated to the spatial description of TLEs and their parent lightning. They are able to differentiate sprite and lightning thanks to two narrow bands ([757-767 nm] and [772-782 nm]) that provide simultaneous pairs of images of an Event. Simulation results of the differentiation method will be shown. After calibration and tests, the MicroCameras are now delivered to the CNES for integration on the payload. The Photometers, developed by Bertin Technologies, will provide temporal measurements and spectral characteristics of TLEs and lightning. There are key instrument because of their capability to detect on-board TLEs and then switch all the instruments of the scientific payload in their high resolution acquisition mode. Photometers use four spectral bands in the [170-260 nm], [332-342 nm], [757-767 nm] and [600-900 nm] and have the same field of view as cameras. The on-board TLE detection algorithm remote-controlled parameters have been tuned before launch using the electronic board and simulated or real events waveforms. After calibration, the Photometers are now going through the environmental tests. They will be delivered to the CNES for integration on the

  6. Auger transitions in singly and multiply ionized atoms

    International Nuclear Information System (INIS)

    Mehlhorn, W.

    1978-01-01

    Some recent progress in Auger and autoionizing electron spectrometry of free metal atoms and of multiply ionized atoms is reviewed. The differences which arise between the spectra of atoms in the gaseous and the solid state are due to solid state effects. This will be shown for Cd as an example. The super Coster-Kronig transitions 3p-3d 2 (hole notation) and Coster-Kronig transitions 3p-3d 4s have been measured and compared with free-atom calculations for free Zn atoms. The experimental width GAMMA(3p)=(2.1+-0.2)eV found for the free atom agrees with the value obtained for solid Zn but is considerably smaller than the theoretical value for the free atom. Autoionizing spectra of Na following an L-shell excitation or ionization by different particles are compared and discussed. The nonisotropic angular distribution of electrons from the transition 2p 5 3s 2 2 Psub(3/2)→2p 6 +e - is compared with theoretical calculations. Two examples for Auger spectrometry of multiply ionized atoms are given: (1) excitation of neon target atoms by light and heavy ions, and (2) excitation of projectile ions Be + and B + in single gas collisions with CH 4 . A strong alignment of the excited atoms has also been found here

  7. Anti-inflammatory effect of resveratrol on TNF-α-induced MCP-1 expression in adipocytes

    International Nuclear Information System (INIS)

    Zhu Jian; Yong Wei; Wu Xiaohong; Yu Ying; Lv Jinghuan; Liu Cuiping; Mao Xiaodong; Zhu Yunxia; Xu Kuanfeng; Han Xiao; Liu Chao

    2008-01-01

    Chronic low-grade inflammation characterized by adipose tissue macrophage accumulation and abnormal cytokine production is a key feature of obesity and type 2 diabetes. Adipose-tissue-derived monocyte chemoattractant protein (MCP)-1, induced by cytokines, has been shown to play an essential role in the early events during macrophage infiltration into adipose tissue. In this study we investigated the effects of resveratrol upon both tumor necrosis factor (TNF)-α-induced MCP-1 gene expression and its underlying signaling pathways in 3T3-L1 adipoctyes. Resveratrol was found to inhibit TNF-α-induced MCP-1 secretion and gene transcription, as well as promoter activity, which based on down-regulation of TNF-α-induced MCP-1 transcription. Nuclear factor (NF)-κB was determined to play a major role in the TNF-α-induced MCP-1 expression. Further analysis showed that resveratrol inhibited DNA binding activity of the NF-κB complex and subsequently suppressed NF-κB transcriptional activity in TNF-α-stimulated cells. Finally, the inhibition of MCP-1 may represent a novel mechanism of resveratrol in preventing obesity-related pathologies

  8. Melanocyte pigmentation inversely correlates with MCP-1 production and angiogenesis-inducing potential.

    Science.gov (United States)

    Adini, Irit; Adini, Avner; Bazinet, Lauren; Watnick, Randolph S; Bielenberg, Diane R; D'Amato, Robert J

    2015-02-01

    The incidence of certain angiogenesis-dependent diseases is higher in Caucasians than in African Americans. Angiogenesis is amplified in wound healing and cornea models in albino C57 mice compared with black C57 mice. Moreover, mouse and human melanocytes with low pigmentation stimulate endothelial cell (EC) proliferation and migration in vitro more than melanocytes with high pigmentation. This effect is due, in part, to the secretion of an angiogenic protein called fibromodulin (FMOD) from lowly pigmented melanocytes. Herein, we expand upon the mechanism contributing to increased angiogenesis in lighter skin and report that monocyte chemotactic protein-1 (MCP-1) is secreted by nonpigmented mouse melanocytes by 5- to 10-fold more than pigmented melanocytes. MCP-1 protein stimulates EC proliferation and migration in vitro and angiogenesis in vivo. Mechanistic studies determine that FMOD is upstream of MCP-1 and promotes its secretion from both melanocytes and activated ECs via stimulation of NF-κB activity. Mice injected with FMOD-neutralizing antibodies show 2.3-fold decreased levels of circulating MCP-1. Human studies confirmed that, on average, Caucasians have 2-fold higher serum levels of MCP-1 than African Americans. Taken together, this study implicates the FMOD/MCP-1 pathway in the regulation of angiogenesis by local melanocytes and suggests that melanogenic activity may protect against aberrant angiogenic diseases. © FASEB.

  9. 2Kx2K resolution element photon counting MCP sensor with >200 kHz event rate capability

    CERN Document Server

    Vallerga, J V

    2000-01-01

    Siegmund Scientific undertook a NASA Small Business Innovative Research (SBIR) contract to develop a versatile, high-performance photon (or particle) counting detector combining recent technical advances in all aspects of Microchannel Plate (MCP) detector development in a low cost, commercially viable package that can support a variety of applications. The detector concept consists of a set of MCPs whose output electron pulses are read out with a crossed delay line (XDL) anode and associated high-speed event encoding electronics. The delay line anode allows high-resolution photon event centroiding at very high event rates and can be scaled to large formats (>40 mm) while maintaining good linearity and high temporal stability. The optimal sensitivity wavelength range is determined by the choice of opaque photocathodes. Specific achievements included: spatial resolution of 200 000 events s sup - sup 1; local rates of >100 events s sup - sup 1 per resolution element; event timing of <1 ns; and low background ...

  10. Hydrogen retention behavior of beryllides as advanced neutron multipliers

    Directory of Open Access Journals (Sweden)

    Y. Fujii

    2016-12-01

    Full Text Available Beryllium intermetallic compounds (beryllides are the most promising candidate materials for use as advanced neutron multipliers in future fusion reactors because of their low swelling and high stability at high temperatures. Recently, beryllium–titanium beryllide pebbles such as Be12Ti have been successfully fabricated using a novel granulation process. In this study, the fundamental aspects of the behavior of hydrogen isotopes in Be12Ti pebbles were investigated via thermal desorption spectroscopy and transmission electron microscopy. In addition, atomistic calculations using first principles electronic-structure methods were applied to determine the solution energy of hydrogen in Be12Ti. The results showed simpler and weaker hydrogen-trapping efficiency for Be12Ti than for pure Be.

  11. Outer-shell transitions in collisions between multiply charged ions and atoms

    International Nuclear Information System (INIS)

    Bloemen, E.W.P.

    1980-01-01

    The study of collisions between multiply charged ions and atoms (molecules) is of importance in different areas of research. Usually, the most important process is capture of an electron from the target atom into the projectile ion. In most cases the electron goes to an excited state of the projectile ion. These electron capture processes are studied. The author also studied direct excitation of the target atom and of the projectile ion. (Auth.)

  12. Equations for the stochastic cumulative multiplying chain

    Energy Technology Data Exchange (ETDEWEB)

    Lewins, J D [Cambridge Univ. (UK). Dept. of Engineering

    1980-01-01

    The forward and backward equations for the conditional probability of the neutron multiplying chain are derived in a new generalization accounting for the chain length and admitting time dependent properties. These Kolmogorov equations form the basis of a variational and hence complete description of the 'lumped' multiplying system. The equations reduce to the marginal distribution, summed over all chain lengths, and to the simpler equations previously derived for that problem. The method of derivation, direct and in the probability space with the minimum of mathematical manipulations, is perhaps the chief attraction: the equations are also displayed in conventional generating function form. As such, they appear to apply to number of problems in areas of social anthropology, polymer chemistry, genetics and cell biology as well as neutron reactor theory and radiation damage.

  13. Equations for the stochastic cumulative multiplying chain

    International Nuclear Information System (INIS)

    Lewins, J.D.

    1980-01-01

    The forward and backward equations for the conditional probability of the neutron multiplying chain are derived in a new generalization accounting for the chain length and admitting time dependent properties. These Kolmogorov equations form the basis of a variational and hence complete description of the 'lumped' multiplying system. The equations reduce to the marginal distribution, summed over all chain lengths, and to the simpler equations previously derived for that problem. The method of derivation, direct and in the probability space with the minimum of mathematical manipulations, is perhaps the chief attraction: the equations are also displayed in conventional generating function form. As such, they appear to apply to number of problems in areas of social anthropology, polymer chemistry, genetics and cell biology as well as neutron reactor theory and radiation damage. (author)

  14. Tourism multipliers in the Mexican economy

    Directory of Open Access Journals (Sweden)

    Antonio Kido-Cruz

    2016-12-01

    Full Text Available This paper presents an analysis of the multiplier impact generated by the tourism sector in Mexico in the year 2013. The importance of studying this sector, in particular, lies in its contribution to the National GDP of over 8% and in its promising development based on services’ quality and the preferred destination of the developed countries. In addition, it is proposed to simulate the multiplier impact that will generate two current events, as they are, the construction of the new International Airport of Mexico and the increase of the investment in Fibers. The results were very punctual, a better distribution of the investment is generated, it is invested in the tourism sector, mainly in variables such as value added and remuneration.

  15. Integrated optic vector-matrix multiplier

    Science.gov (United States)

    Watts, Michael R [Albuquerque, NM

    2011-09-27

    A vector-matrix multiplier is disclosed which uses N different wavelengths of light that are modulated with amplitudes representing elements of an N.times.1 vector and combined to form an input wavelength-division multiplexed (WDM) light stream. The input WDM light stream is split into N streamlets from which each wavelength of the light is individually coupled out and modulated for a second time using an input signal representing elements of an M.times.N matrix, and is then coupled into an output waveguide for each streamlet to form an output WDM light stream which is detected to generate a product of the vector and matrix. The vector-matrix multiplier can be formed as an integrated optical circuit using either waveguide amplitude modulators or ring resonator amplitude modulators.

  16. Tax Multipliers: Pitfalls in Measurement and Identification

    OpenAIRE

    Daniel Riera-Crichton; Carlos A. Vegh; Guillermo Vuletin

    2012-01-01

    We contribute to the literature on tax multipliers by analyzing the pitfalls in identification and measurement of tax shocks. Our main focus is on disentangling the discussion regarding the identification of exogenous tax policy shocks (i.e., changes in tax policy that are not the result of policymakers responding to output fluctuations) from the discussion related to the measurement of tax policy (i.e., finding a tax policy variable under the direct control of the policymaker). For this purp...

  17. Multiplier-free filters for wideband SAR

    DEFF Research Database (Denmark)

    Dall, Jørgen; Christensen, Erik Lintz

    2001-01-01

    This paper derives a set of parameters to be optimized when designing filters for digital demodulation and range prefiltering in SAR systems. Aiming at an implementation in field programmable gate arrays (FPGAs), an approach for the design of multiplier-free filters is outlined. Design results...... are presented in terms of filter complexity and performance. One filter has been coded in VHDL and preliminary results indicate that the filter can meet a 2 GHz input sample rate....

  18. Mining, regional Australia and the economic multiplier

    Directory of Open Access Journals (Sweden)

    Paul Cleary

    2012-12-01

    Full Text Available Mining in Australia has traditionally delivered a strong development multiplier for regional communities where most mines are based. This relationship has weakened in recent decades as a result of the introduction of mobile workforces - typically known as fly in, fly out. Political parties have responded with policies known as ‘royalties for regions’, though in designing them they overlooked long established Indigenous arrangements for sharing benefits with areas affected directly by mining.

  19. The Uncertainty Multiplier and Business Cycles

    OpenAIRE

    Saijo, Hikaru

    2013-01-01

    I study a business cycle model where agents learn about the state of the economy by accumulating capital. During recessions, agents invest less, and this generates noisier estimates of macroeconomic conditions and an increase in uncertainty. The endogenous increase in aggregate uncertainty further reduces economic activity, which in turn leads to more uncertainty, and so on. Thus, through changes in uncertainty, learning gives rise to a multiplier effect that amplifies business cycles. I use ...

  20. A mechanistic modelling approach to understand 1-MCP inhibition of ethylene action and quality changes during ripening of apples.

    Science.gov (United States)

    Gwanpua, Sunny George; Verlinden, Bert E; Hertog, Maarten Latm; Nicolai, Bart M; Geeraerd, Annemie H

    2017-08-01

    1-Methylcyclopropene (1-MCP) inhibits ripening in climacteric fruit by blocking ethylene receptors, preventing ethylene from binding and eliciting its action. The objective of the current study was to use mathematical models to describe 1-MCP inhibition of apple fruit ripening, and to provide a tool for predicting ethylene production, and two important quality indicators of apple fruit, firmness and background colour. A model consisting of coupled differential equations describing 1-MCP inhibition of apple ripening was developed. Data on ethylene production, expression of ethylene receptors, firmness, and background colour during ripening of untreated and 1-MCP treated apples were used to calibrate the model. An overall adjusted R 2 of 95% was obtained. The impact of time from harvest to treatment, and harvest maturity on 1-MCP efficacy was modelled. Different hypotheses on the partial response of 'Jonagold' apple to 1-MCP treatment were tested using the model. The model was validated using an independent dataset. Low 1-MCP blocking efficacy was shown to be the most likely cause of partial response for delayed 1-MCP treatment, and 1-MCP treatment of late-picked apples. Time from harvest to treatment was a more important factor than maturity for 1-MCP efficacy in 'Jonagold' apples. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  1. Monocyte chemoattractant protein-1 (MCP-1 regulates macrophage cytotoxicity in abdominal aortic aneurysm.

    Directory of Open Access Journals (Sweden)

    Qiwei Wang

    Full Text Available AIMS: In abdominal aortic aneurysm (AAA, macrophages are detected in the proximity of aortic smooth muscle cells (SMCs. We have previously demonstrated in a murine model of AAA that apoptotic SMCs attract monocytes and other leukocytes by producing MCP-1. Here we tested whether infiltrating macrophages also directly contribute to SMC apoptosis. METHODS AND RESULTS: Using a SMC/RAW264.7 macrophage co-culture system, we demonstrated that MCP-1-primed RAWs caused a significantly higher level of apoptosis in SMCs as compared to control macrophages. Next, we detected an enhanced Fas ligand (FasL mRNA level and membrane FasL protein expression in MCP-1-primed RAWs. Neutralizing FasL blocked SMC apoptosis in the co-culture. In situ proximity ligation assay showed that SMCs exposed to primed macrophages contained higher levels of receptor interacting protein-1 (RIP1/Caspase 8 containing cell death complexes. Silencing RIP1 conferred apoptosis resistance to SMCs. In the mouse elastase injury model of aneurysm, aneurysm induction increased the level of RIP1/Caspase 8 containing complexes in medial SMCs. Moreover, TUNEL-positive SMCs in aneurysmal tissues were frequently surrounded by CD68(+/FasL(+ macrophages. Conversely, elastase-treated arteries from MCP-1 knockout mice display a reduction of both macrophage infiltration and FasL expression, which was accompanied by diminished apoptosis of SMCs. CONCLUSION: Our data suggest that MCP-1-primed macrophages are more cytotoxic. MCP-1 appears to modulate macrophage cytotoxicity by increasing the level of membrane bound FasL. Thus, we showed that MCP-1-primed macrophages kill SMCs through a FasL/Fas-Caspase8-RIP1 mediated mechanism.

  2. Isometric multipliers of a vector valued Beurling algebra on a ...

    Indian Academy of Sciences (India)

    Home; Journals; Proceedings – Mathematical Sciences; Volume 127; Issue 1. Isometric multipliers of a vector valued Beurling algebra on a discrete semigroup. Research Article Volume 127 Issue 1 February 2017 pp 109- ... Keywords. Weighted semigroup; multipliers of a semigroup; Beurling algebra; isometric multipliers.

  3. Thioredoxin reductase 1 upregulates MCP-1 release in human endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhen-Bo [Institute of Biophysics, Chinese Academy of Sciences, and Graduate School of the Chinese Academy of Sciences, Beijing (China); Shen, Xun, E-mail: shenxun@sun5.ibp.ac.cn [Institute of Biophysics, Chinese Academy of Sciences, and Graduate School of the Chinese Academy of Sciences, Beijing (China)

    2009-09-04

    To know if thioredoxin reductase 1 (TrxR1) plays a role in antioxidant defense mechanisms against atherosclerosis, effect of TrxR1 on expression/release of monocyte chemoattractant protein (MCP-1) was investigated in activated human endothelial-like EAhy926 cells. The MCP-1 release and expression, cellular generation of reactive oxygen species (ROS), nuclear translocation and DNA-binding activity of NF-{kappa}B subunit p65 were assayed in cells either overexpressing recombinant TrxR1 or having their endogenous TrxR1 knocked down. It was found that overexpression of TrxR1 enhanced, while knockdown of TrxR1 reduced MCP-1 release and expression. Upregulation of MCP-1 by TrxR1 was associated with increasing generation of intracellular ROS generation, enhanced nuclear translocation and DNA-binding activity of NF-{kappa}B. Assay using NF-{kappa}B reporter revealed that TrxR1 upregulated transcriptional activity of NF-{kappa}B. This study suggests that TrxR1 enhances ROS generation, NF-{kappa}B activity and subsequent MCP-1 expression in endothelial cells, and may promote rather than prevent vascular endothelium from forming atherosclerotic plaque.

  4. IL-8 and MCP Gene Expression and Production by LPS-Stimulated Human Corneal Stromal Cells

    Directory of Open Access Journals (Sweden)

    Roni M. Shtein

    2012-01-01

    Full Text Available Purpose. To determine time course of effect of lipopolysaccharide (LPS on production of interleukin-8 (IL-8 and monocyte chemotactic protein (MCP by cultured human corneal stromal cells. Methods. Human corneal stromal cells were harvested from donor corneal specimens, and fourth to sixth passaged cells were used. Cell cultures were stimulated with LPS for 2, 4, 8, and 24 hours. Northern blot analysis of IL-8 and MCP gene expression and ELISA for IL-8 and MCP secretion were performed. ELISA results were analyzed for statistical significance using two-tailed Student's t-test. Results. Northern blot analysis demonstrated significantly increased IL-8 and MCP gene expression after 4 and 8 hours of exposure to LPS. ELISA for secreted IL-8 and MCP demonstrated statistically significant increases (P<0.05 after corneal stromal cell stimulation with LPS. Conclusions. This paper suggests that human corneal stromal cells may participate in corneal inflammation by secreting potent leukocyte chemotactic and activating proteins in a time-dependent manner when exposed to LPS.

  5. Study of heterogeneous multiplying and non-multiplying media by the neutron pulsed source technique

    International Nuclear Information System (INIS)

    Deniz, V.

    1969-01-01

    The pulsed neutron technique consists essentially in sending in the medium to be studied a short neutron pulse and in determining the asymptotic decay constant of the generated population. The variation of the decay constant as a function of the size of the medium allows the medium characteristics to be defined. This technique has been largely developed these last years and has been applied as well to moderator as to multiplying media, in most cases homogeneous ones. We considered of interest of apply this technique to lattices, to see if useful informations could be collected for lattice calculations. We present here a general theoretical study of the problem, and results and interpretation of a series of experiments made on graphite lattices. There is a good agreement for non-multiplying media. In the case of multiplying media, it is shown that the age value used until now in graphite lattices calculations is over-estimated by about 10 per cent [fr

  6. JNK-induced MCP-1 production in spinal cord astrocytes contributes to central sensitization and neuropathic pain.

    Science.gov (United States)

    Gao, Yong-Jing; Zhang, Ling; Samad, Omar Abdel; Suter, Marc R; Yasuhiko, Kawasaki; Xu, Zhen-Zhong; Park, Jong-Yeon; Lind, Anne-Li; Ma, Qiufu; Ji, Ru-Rong

    2009-04-01

    Our previous study showed that activation of c-jun-N-terminal kinase (JNK) in spinal astrocytes plays an important role in neuropathic pain sensitization. We further investigated how JNK regulates neuropathic pain. In cultured astrocytes, tumor necrosis factor alpha (TNF-alpha) transiently activated JNK via TNF receptor-1. Cytokine array indicated that the chemokine CCL2/MCP-1 (monocyte chemoattractant protein-1) was strongly induced by the TNF-alpha/JNK pathway. MCP-1 upregulation by TNF-alpha was dose dependently inhibited by the JNK inhibitors SP600125 (anthra[1,9-cd]pyrazol-6(2H)-one) and D-JNKI-1. Spinal injection of TNF-alpha produced JNK-dependent pain hypersensitivity and MCP-1 upregulation in the spinal cord. Furthermore, spinal nerve ligation (SNL) induced persistent neuropathic pain and MCP-1 upregulation in the spinal cord, and both were suppressed by D-JNKI-1. Remarkably, MCP-1 was primarily induced in spinal cord astrocytes after SNL. Spinal administration of MCP-1 neutralizing antibody attenuated neuropathic pain. Conversely, spinal application of MCP-1 induced heat hyperalgesia and phosphorylation of extracellular signal-regulated kinase in superficial spinal cord dorsal horn neurons, indicative of central sensitization (hyperactivity of dorsal horn neurons). Patch-clamp recordings in lamina II neurons of isolated spinal cord slices showed that MCP-1 not only enhanced spontaneous EPSCs but also potentiated NMDA- and AMPA-induced currents. Finally, the MCP-1 receptor CCR2 was expressed in neurons and some non-neuronal cells in the spinal cord. Together, we have revealed a previously unknown mechanism of MCP-1 induction and action. MCP-1 induction in astrocytes after JNK activation contributes to central sensitization and neuropathic pain facilitation by enhancing excitatory synaptic transmission. Inhibition of the JNK/MCP-1 pathway may provide a new therapy for neuropathic pain management.

  7. A high reliability automatic multiplier for a mass spectrometer ion detector circuit

    International Nuclear Information System (INIS)

    Hoshino, Kiichi; Satooka, Sakae

    1978-01-01

    An automatic multiplier of an ion detector circuit for measurement of isotopic abundance ratio of heavy hydrogen to be used with a single collector has been constructed. This multiplier works at 1/1, 1/5, 1/20, 1/100, 1/500, 1/2000 and infinity, and the input voltage which is required to change the range from 1/1 to 1/5 is 10 mV and that from 1/2000 to infinity is 20 V. As the amplifier preceding the automatic multiplier, a vibrating reed electrometer which generates maximum output of 30 V is used. On measurement, marks which indicate the magnifications are recorded on the chart of electronic recorder. It is possible to set the minimum magnification at 1/1, 1/5, or 1/20 by a switch for setting the minimum magnification. (author)

  8. CHANGES IN MECHANICAL PROPERTIES OF MINIMALLY-PROCESSED YELLOW PITAHAYA TREATED WITH 1-MCP

    Directory of Open Access Journals (Sweden)

    LILIANA SERNA COCK

    2012-01-01

    Full Text Available Se evaluaron las propiedades mecánicas de esfuerzo del límite de fluencia (sL, modulo de deformación (Ed, esfuerzo de ruptura (sF, y deformación de Hencky en la ruptura (eHF de muestras de pitahaya amarilla mínimamente procesada y tratadas con 200 μgL-1 de 1-MCP durante el almacenamiento a 10±1 °C y 85% de humedad relativa. Las muestras fueron sometidas a pruebas de compresión uniaxial hasta la ruptura. Los resultados mostraron que las muestras tratadas con 1-MCP presentaron los mayores valores del esfuerzo del límite de fluencia, modulo de elasticidad y esfuerzo de ruptura. Esto indica que la aplicación del 1-MCP proporciona mayor firmeza a la fruta y puede representar una alternativa para disminuir cambios indeseables de textura durante el almacenamiento.

  9. Transient phenomena in bounded fast multiplying assemblies

    International Nuclear Information System (INIS)

    Kraft, T.E.

    1976-01-01

    A generalized dispersion formalism is developed in the context of time-, space-, and energy-dependent transport theory. The evolution of the neutron population in a fast multiplying system following an initial burst of neutrons is examined. The generalized dispersion law obtained is an integral equation, in one variable, for the Laplace and Fourier transformed time- and space-dependent sources of fission neutrons. An approximation technique is shown to generate solutions which converge in L 2 norm to the exact solution for exact elastic, exact inelastic, Goertzel-Grueling or Wigner scattering kernels, and any reasonable fission spectrum

  10. Quasiparticle trapping and the quasiparticle multiplier

    International Nuclear Information System (INIS)

    Booth, N.E.

    1987-01-01

    Superconductors and in particular superconducting tunnel junctions can be used to detect phonons, electromagnetic radiation, x rays, and nuclear particles by the mechanism of Cooper-pair breaking to produce excess quasiparticles and phonons. We show that the sensitivity can be increased by a factor of 100 or more by trapping the quasiparticles in another superconductor of lower gap in the region of the tunnel junction. Moreover, if the ratio of the gap energies is >3 a multiplication process can occur due to the interaction of the relaxation phonons. This leads to the concept of the quasiparticle multiplier, a device which could have wider applications than the Gray effect transistor or the quiteron

  11. Multipliers on Generalized Mixed Norm Sequence Spaces

    Directory of Open Access Journals (Sweden)

    Oscar Blasco

    2014-01-01

    Full Text Available Given 1≤p,q≤∞ and sequences of integers (nkk and (nk′k such that nk≤nk′≤nk+1, the generalized mixed norm space ℓℐ(p,q is defined as those sequences (ajj such that ((∑j∈Ik‍|aj|p1/pk∈ℓq where Ik={j∈ℕ0 s.t. nk≤jmultipliers (ℓℐ(r,s,ℓ(u,v, for different sequences ℐ and of intervals in ℕ0, are determined.

  12. Impact of MCP-1 and CCR-2 gene polymorphisms on coronary artery disease susceptibility.

    Science.gov (United States)

    Lin, Hsiu-Ling; Ueng, Kwo-Chang; Hsieh, Yih-Shou; Chiang, Whei-Ling; Yang, Shun-Fa; Chu, Shu-Chen

    2012-09-01

    Coronary artery disease (CAD) was the second leading cause of death during the last 3 years in Taiwan. Smooth muscle cells, monocytes/macrophages, and endothelial cells produce monocyte chemoattractant protein-1 (MCP-1) within atherosclerotic plaques following binding to the chemokine receptor-2 (CCR-2). Previous studies have well-documented the association between MCP-1 expression and susceptibility to, or clinicopathological features, of CAD. This study investigated the relationships between MCP-1-2518A/G and CCR-2-V64I genetic polymorphisms and CAD in the Taiwanese population. A total of 608 subjects, including 392 non-CAD controls and 216 patients with CAD, were recruited and subjected to polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to evaluate the effects of these two polymorphic variants on CAD. Results indicated a significant association between MCP-1 -2548 gene polymorphism and susceptibility to CAD. GG genotypes (OR = 1.629; 95 % CI = 1.003-2.644), or individuals with at least one G allele (OR = 1.511; 95 % CI = 1.006-2.270), had a higher risk of CAD as compared with AA genotypes. Results also revealed that subjects with at least one A allele of the V64I CCR2 gene polymorphism had significantly increased risk of CAD. G allele in MCP-1-2518 might contribute to higher prevalence of atrial fibrillation in CAD patients (OR = 4.254; p CCR-2 64I gene polymorphisms represent important factors in determining susceptibility to CAD, and the contribution of MCP-1-2518G could be through effects on atrial fibrillation in CAD patients.

  13. Capacitively coupled pickup in MCP-based photodetectors using a conductive metallic anode

    Energy Technology Data Exchange (ETDEWEB)

    Angelico, E.; Seiss, T. [Enrico Fermi Institute, University of Chicago, 5640 S Ellis Ave, Chicago, IL 60637 (United States); Adams, B. [Incom, Inc., 294 SouthBridge Rd, Charlton, Massachusetts 01507 (United States); Elagin, A.; Frisch, H.; Spieglan, E. [Enrico Fermi Institute, University of Chicago, 5640 S Ellis Ave, Chicago, IL 60637 (United States)

    2017-02-21

    We have designed and tested a robust 20×20 cm{sup 2} thin metal film internal anode capacitively coupled to an external array of signal pads or micro-strips for use in fast microchannel plate photodetectors. The internal anode, in this case a 10 nm-thick NiCr film deposited on a 96% pure Al{sub 2}O{sub 3} 3 mm-thick ceramic plate and connected to HV ground, provides the return path for the electron cascade charge. The multi-channel pickup array consists of a printed-circuit card or glass plate with metal signal pickups on one side and the signal ground plane on the other. The pickup can be put in close proximity to the bottom outer surface of the sealed photodetector, with no electrical connections through the photodetector hermetic vacuum package other than a single ground connection to the internal anode. Two pickup patterns were tested using a small commercial MCP-PMT as the signal source: 1) parallel 50 Ω 25-cm-long micro-strips with an analog bandwidth of 1.5 GHz, and 2) a 20×20 cm{sup 2} array of 2-dimensional square ‘pads’ with sides of 1.27 cm or 2.54 cm. The rise-time of the fast input pulse is maintained for both pickup patterns. For the pad pattern, we observe 80% of the directly coupled amplitude. For the strip pattern we measure 34% of the directly coupled amplitude on the central strip of a broadened signal. The physical decoupling of the photodetector from the pickup pattern allows easy customization for different applications while maintaining high analog bandwidth.

  14. Synthesis of highly faceted multiply twinned gold nanocrystals stabilized by polyoxometalates

    International Nuclear Information System (INIS)

    Yuan Junhua; Chen Yuanxian; Han Dongxue; Zhang Yuanjian; Shen Yanfei; Wang Zhijuan; Niu Li

    2006-01-01

    A novel and facile chemical synthesis of highly faceted multiply twinned gold nanocrystals is reported. The gold nanocrystals are hexagonal in transmission electron microscopy and icosahedral in scanning electron microscopy. Phosphotungstic acid (PTA), which was previously reduced, serves as a reductant and stabilizer for the synthesis of gold nanocrystals. The PTA-gold nanocomposites are quite stable in aqueous solutions, and electrochemically active towards the hydrogen evolution reaction

  15. Development of 10×10 Matrix-anode MCP-PMT

    Science.gov (United States)

    Yang, Jie; Li, Yongbin; Xu, Pengxiao; Zhao, Wenjin

    2018-02-01

    10×10 matrix-anode is developed by high-temperature co-fired ceramics (HTCC) technology. Based on the new matrix-anode, a new kind of photon counting imaging detector - 10×10 matrix-anode MCP-PMT is developed, and its performance parameters are tested. HTCC technology is suitable for the MCP-PMT's air impermeability and its baking process. Its response uniformity is better than the metal-ceramic or metal-glass sealing anode, and it is also a promising method to realize a higher density matrix-anode.

  16. A 30 ps Timing Resolution for Single Photons with Multi-pixel Burle MCP-PMT

    Energy Technology Data Exchange (ETDEWEB)

    Va' vra, J.; Benitez, J.; Coleman, J.; Leith, D.W.G.S.; Mazaheri, G.; Ratcliff, B.; Schwiening, J.; /SLAC

    2006-07-05

    We have achieved {approx}30 psec single-photoelectron and {approx}12ps for multi-photoelectron timing resolution with a new 64 pixel Burle MCP-PMT with 10 micron microchannel holes. We have also demonstrated that this detector works in a magnetic field of 15kG, and achieved a single-photoelectron timing resolution of better than 60 psec. The study is relevant for a new focusing DIRC RICH detector for particle identification at future Colliders such as the super B-factory or ILC, and for future TOF techniques. This study shows that a highly pixilated MCP-PMT can deliver excellent timing resolution.

  17. MCP-1 Levels are Associated with Cardiac Remodeling but not with Resistant Hypertension.

    Science.gov (United States)

    Ritter, Alessandra Mileni Versuti; Faria, Ana Paula Cabral de; Sabbatini, Andrea; Corrêa, Nathalia Batista; Brunelli, Veridiana; Modolo, Rodrigo; Moreno, Heitor

    2017-04-01

    Hypertension is a chronic, low-grade inflammation process associated with the release of cytokines and development of target organ damage. Deregulated monocyte chemoattractant protein-1 (MCP-1) levels have been associated with high blood pressure and cardiovascular complications; however, the mechanisms involved are complex and not fully understood. This study aimed to compare the levels of MCP-1 in patients with resistant (RH) versus mild-to-moderate (HTN) hypertension and their association with the presence or absence of left ventricular hypertrophy (LVH) in all hypertensive subjects. We enrolled 256 hypertensive subjects: 120 RH and 136 HTN, investigating the relationship between circulating MCP-1 levels and blood pressure, biochemical data, hematologic profile, and cardiac damage within the RH and HTN groups. Plasma MCP-1 levels were measured by ELISA and LVH was assessed by echocardiography. We found no difference in MCP-1 levels between RH and HTN subjects. On the other hand, we encountered lower MCP-1 levels in patients with LVH (105 pg/mL [100 - 260 pg/mL] versus 136 pg/mL (100 - 200 pg/mL), p = 0.005, respectively] compared with those without LVH. A logistic regression model adjusted for body mass index (BMI), age, race, aldosterone levels, and presence of diabetes and RH demonstrated that median levels of MCP-1 (2.55 pg/mL [1.22 - 5.2 pg/mL], p = 0.01) were independently associated with LVH in the entire hypertensive population. Since MCP-1 levels were similar in both RH and HTN subjects and decreased in hypertensive patients with existing LVH, our study suggests a possible downregulation in MCP-1 levels in hypertensive individuals with LVH, regardless of hypertension strata. A hipertensão arterial é um processo crônico de baixo grau inflamatório, associado com liberação de citocinas e desenvolvimento de lesão em órgãos-alvo. A desregulação dos níveis de proteína quimiotática de monócitos-1 (MCP-1) tem sido associada com elevação da press

  18. Rhinoplasty for the multiply revised nose.

    Science.gov (United States)

    Foda, Hossam M T

    2005-01-01

    To evaluate the problems encountered on revising a multiply operated nose and the methods used in correcting such problems. The study included 50 cases presenting for revision rhinoplasty after having had 2 or more previous rhinoplasties. An external rhinoplasty approach was used in all cases. Simultaneous septal surgery was done whenever indicated. All cases were followed for a mean period of 32 months (range, 1.5-8 years). Evaluation of the surgical result depended on clinical examination, comparison of pre- and postoperative photographs, and degree of patients' satisfaction with their aesthetic and functional outcome. Functionally, 68% suffered nasal obstruction that was mainly caused by septal deviations and nasal valve problems. Aesthetically, the most common deformities of the upper two thirds of the nose included pollybeak (64%), dorsal irregularities (54%), dorsal saddle (44%), and open roof deformity (42%), whereas the deformities of lower third included depressed tip (68%), tip contour irregularities (60%), and overrotated tip (42%). Nasal grafting was necessary in all cases; usually more than 1 type of graft was used in each case. Postoperatively, 79% of the patients, with preoperative nasal obstruction, reported improved breathing; 84% were satisfied with their aesthetic result; and only 8 cases (16%) requested further revision to correct minor deformities. Revision of a multiply operated nose is a complex and technically demanding task, yet, in a good percentage of cases, aesthetic as well as functional improvement are still possible.

  19. Quantum mechanics in a multiply connected region

    International Nuclear Information System (INIS)

    Miyazawa, H.

    1986-01-01

    It is usually assumed that wave fields or wave functions are single valued functions of space-time. However, the phase of a complex field is an unobservable quantity and there is no obvious reason that it must be single valued. On this point quantum mechanics in a multiply connected regions is not well formulated. This ambiguity appears e.g., in the case of the Bohm-Aharonov effect concerning the observability of the vector potential around a magnetic flux. The author discusses the single or multiple valuedness of wave functions and attempts to see if such an effect really exists or not. The wave function of a charged particle in a multiply connected region is not necessarily single valued. The condition that the ground state energy be a minimum fixes the character of the multiple valuedness. For a charged particle around a magnetic flux a multiple valued wave function is preferable and no Bohm-Aharonov effect is observed. The minimum energy principle is proved if one also considers the interaction of a charged particle with external objects. Then theoretically the Bohm-Aharonov effect should not be observed. Experiments are not yet conclusive on this point

  20. MCP/CCR2 signaling is essential for recruitment of mesenchymal progenitor cells during the early phase of fracture healing.

    Directory of Open Access Journals (Sweden)

    Masahiro Ishikawa

    Full Text Available OBJECTIVE: The purpose of this study was to investigate chemokine profiles and their functional roles in the early phase of fracture healing in mouse models. METHODS: The expression profiles of chemokines were examined during fracture healing in wild-type (WT mice using a polymerase chain reaction array and histological staining. The functional effect of monocyte chemotactic protein-1 (MCP-1 on primary mouse bone marrow stromal cells (mBMSCs was evaluated using an in vitro migration assay. MCP-1-/- and C-C chemokine receptor 2 (CCR2-/- mice were fractured and evaluated by histological staining and micro-computed tomography (micro-CT. RS102895, an antagonist of CCR2, was continuously administered in WT mice before or after rib fracture and evaluated by histological staining and micro-CT. Bone graft exchange models were created in WT and MCP-1-/- mice and were evaluated by histological staining and micro-CT. RESULTS: MCP-1 and MCP-3 expression in the early phase of fracture healing were up-regulated, and high levels of MCP-1 and MCP-3 protein expression observed in the periosteum and endosteum in the same period. MCP-1, but not MCP-3, increased migration of mBMSCs in a dose-dependent manner. Fracture healing in MCP-1-/- and CCR2-/- mice was delayed compared with WT mice on day 21. Administration of RS102895 in the early, but not in the late phase, caused delayed fracture healing. Transplantation of WT-derived graft into host MCP-1-/- mice significantly increased new bone formation in the bone graft exchange models. Furthermore, marked induction of MCP-1 expression in the periosteum and endosteum was observed around the WT-derived graft in the host MCP-1-/- mouse. Conversely, transplantation of MCP-1-/- mouse-derived grafts into host WT mice markedly decreased new bone formation. CONCLUSIONS: MCP-1/CCR2 signaling in the periosteum and endosteum is essential for the recruitment of mesenchymal progenitor cells in the early phase of fracture healing.

  1. Use of equimolar cysteine/ascorbic acids to recover MCP synthesized Ti(Mg) alloy

    CSIR Research Space (South Africa)

    Mushove, T

    2010-10-01

    Full Text Available Dissolution of waste by-products of mechanochemical processing (MCP) synthesis of Ti(Mg) alloy, from TiO2 and 15 wt.% excess Mg, was conducted in equimolar cysteine/ascorbic acids. The synthesized alloy is inherently mixed with MgO and other oxides...

  2. 'Diffuse skin browning' in 1-MCP-treated apples: etiology and systems of control.

    Science.gov (United States)

    Larrigaudière, Christian; Vilaplana, Rosa; Recasens, Inmaculada; Soria, Yolanda; Dupille, Eve

    2010-11-01

    'Diffuse skin browning' (DSB) is a physiological disorder that affects Golden Delicious apples treated with 1-methylcyclopropene (1-MCP). Although a very high incidence is found, very little is known about the etiology of this disorder. This study aims to provide an understanding of the causes of this disorder and prevent it. A very high incidence of DSB was found in 1-MCP-treated apples independent of the location of the orchard. Similar to superficial scald, harvest maturity determines the DSB incidence, with the more mature fruit being less sensitive. The 1-MCP dose (156 nL L(-1) or 625 nL L(-1)) and the temperature at which the 1-MCP treatment was applied (0.5 or 20 °C) did not affect the incidence of DSB. Diphenylamine (DPA) treatment did not prevent DSB, contrary to superficial scald. Additionally, controlled atmosphere storage only partially reduced the incidence of DSB, whereas progressive cooling strategies completely inhibited DSB occurrence. A direct correlation was found between the sensitivity of the Golden Delicious clone to russeting and its sensitivity to develop DSB during storage. Our results indicated that DSB and superficial scald are two different disorders involving different oxidative processes. DSB can be prevented by progressive cooling and selection of russeting-resistant clones. 2010 Society of Chemical Industry

  3. Influence of 1-MCP treatments on eating quality and consumer preferences of ‘Qinmei’ kiwifruit during shelf life

    Science.gov (United States)

    Consumers and growers in China sometime complain that Kiwifruits treated with an ethylene action inhibitor 1-MCP are difficult to ripen and show poor eating quality. This study addresses the quality parameters affecting consumer preferences and reevaluates the necessity of 1-MCP application for stor...

  4. Hadamard Multipliers and Abel Dual of Hardy Spaces

    Directory of Open Access Journals (Sweden)

    Paweł Mleczko

    2016-01-01

    Full Text Available The paper is devoted to the study of Hadamard multipliers of functions from the abstract Hardy classes generated by rearrangement invariant spaces. In particular the relation between the existence of such multiplier and the boundedness of the appropriate convolution operator on spaces of measurable functions is presented. As an application, the description of Hadamard multipliers into H∞ is given and the Abel type theorem for mentioned Hardy spaces is proved.

  5. φ-Multipliers on Banach Algebras and Topological Modules

    OpenAIRE

    Adib, Marjan

    2015-01-01

    We prove some results concerning Arens regularity and amenability of the Banach algebra ${M}_{\\phi }(A)$ of all $\\phi $ -multipliers on a given Banach algebra $A$ . We also consider $\\phi $ -multipliers in the general topological module setting and investigate some of their properties. We discuss the $\\phi $ -strict and $\\phi $ -uniform topologies on ${M}_{\\phi }(A)$ . A characterization of $\\phi $ -multipliers on ${L}_{1}(G)$ -module ${L}_{p}(G)$ , where $G$ is a compact group, is given.

  6. Neutron multiplier alternative for fusion reactor blankets

    International Nuclear Information System (INIS)

    Taczanowski, S.

    1980-01-01

    A proposal is given to replace neutron multiplier needed to enable low lithium and tritium inventories simultaneously assuring sufficient production of tritium, by an efficient moderator ( 7 LiH or 7 LiD). The advantageous effect of the intensified neutron energy degradation is due to the 1/v character of the main tritium producing reaction. The slowing-down medium is designed to be the source of moderated neutrons for the surrounding Li ( 6 Li enriched) region where the most of tritium is to be produced. The surplus tritium production remains stored in the moderator zone. Some preliminary calculations illustrating the above concept were carried out and the neutron flux and tritium production distributions are presented. The indications regarding further studies are also suggested. (author)

  7. Four-gate transistor analog multiplier circuit

    Science.gov (United States)

    Mojarradi, Mohammad M. (Inventor); Blalock, Benjamin (Inventor); Cristoloveanu, Sorin (Inventor); Chen, Suheng (Inventor); Akarvardar, Kerem (Inventor)

    2011-01-01

    A differential output analog multiplier circuit utilizing four G.sup.4-FETs, each source connected to a current source. The four G.sup.4-FETs may be grouped into two pairs of two G.sup.4-FETs each, where one pair has its drains connected to a load, and the other par has its drains connected to another load. The differential output voltage is taken at the two loads. In one embodiment, for each G.sup.4-FET, the first and second junction gates are each connected together, where a first input voltage is applied to the front gates of each pair, and a second input voltage is applied to the first junction gates of each pair. Other embodiments are described and claimed.

  8. Faster Double-Size Bipartite Multiplication out of Montgomery Multipliers

    Science.gov (United States)

    Yoshino, Masayuki; Okeya, Katsuyuki; Vuillaume, Camille

    This paper proposes novel algorithms for computing double-size modular multiplications with few modulus-dependent precomputations. Low-end devices such as smartcards are usually equipped with hardware Montgomery multipliers. However, due to progresses of mathematical attacks, security institutions such as NIST have steadily demanded longer bit-lengths for public-key cryptography, making the multipliers quickly obsolete. In an attempt to extend the lifespan of such multipliers, double-size techniques compute modular multiplications with twice the bit-length of the multipliers. Techniques are known for extending the bit-length of classical Euclidean multipliers, of Montgomery multipliers and the combination thereof, namely bipartite multipliers. However, unlike classical and bipartite multiplications, Montgomery multiplications involve modulus-dependent precomputations, which amount to a large part of an RSA encryption or signature verification. The proposed double-size technique simulates double-size multiplications based on single-size Montgomery multipliers, and yet precomputations are essentially free: in an 2048-bit RSA encryption or signature verification with public exponent e=216+1, the proposal with a 1024-bit Montgomery multiplier is at least 1.5 times faster than previous double-size Montgomery multiplications.

  9. Efek Multiplier Zakat terhadap Pendapatan di Provinsi DKI Jakarta

    OpenAIRE

    Al Arif, M. Nur Rianto

    2012-01-01

    The aim of this research is to analyse the multiplier effect of zakâh revenue in DKI Jakarta. A study case at Badan Amil Zakat, Infak, and Sadaqah (BAZIS) DKI Jakarta. Least square method is used to analyze the data. The coefficients will be used to calculate the multiplier effect of zakâh-revenue and it will be compared with the economy without zakah revenue. The results showed 2,522 multiplier effects of zakâh-revenue and 3.561 multiplier effect ofeconomic income without zakâh-revenue. Thi...

  10. Toward a noncytotoxic glioblastoma therapy: blocking MCP-1 with the MTZ Regimen

    Directory of Open Access Journals (Sweden)

    Salacz ME

    2016-04-01

    Full Text Available Michael E Salacz,1,2 Richard E Kast,3 Najmaldin Saki,4 Ansgar Brüning,5 Georg Karpel-Massler,6 Marc-Eric Halatsch6 1Department of Internal Medicine, 2Department of Neurosurgery, University of Kansas, Kansas City, KS, USA; 3IIAIGC Study Center, Burlington, VT, USA; 4Health Research Institute, Research Center of Thalassemia and Hemoglobinopathy, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; 5Molecular Biology Laboratory, University Hospital Munich, Munich, Germany; 6Department of Neurosurgery, University of Ulm, Ulm, Germany Abstract: To improve the prognosis of glioblastoma, we developed an adjuvant treatment directed to a neglected aspect of glioblastoma growth, the contribution of nonmalignant monocyte lineage cells (MLCs (monocyte, macrophage, microglia, dendritic cells that infiltrated a main tumor mass. These nonmalignant cells contribute to glioblastoma growth and tumor homeostasis. MLCs comprise of approximately 10%–30% of glioblastoma by volume. After integration into the tumor mass, these become polarized toward an M2 immunosuppressive, pro-angiogenic phenotype that promotes continued tumor growth. Glioblastoma cells initiate and promote this process by synthesizing 13 kDa MCP-1 that attracts circulating monocytes to the tumor. Infiltrating monocytes, after polarizing toward an M2 phenotype, synthesize more MCP-1, forming an amplification loop. Three noncytotoxic drugs, an antibiotic – minocycline, an antihypertensive drug – telmisartan, and a bisphosphonate – zoledronic acid, have ancillary attributes of MCP-1 synthesis inhibition and could be re-purposed, singly or in combination, to inhibit or reverse MLC-mediated immunosuppression, angiogenesis, and other growth-enhancing aspects. Minocycline, telmisartan, and zoledronic acid – the MTZ Regimen – have low-toxicity profiles and could be added to standard radiotherapy and temozolomide. Re-purposing older drugs has advantages of established safety and low

  11. Encoding Schemes For A Digital Optical Multiplier Using The Modified Signed-Digit Number Representation

    Science.gov (United States)

    Lasher, Mark E.; Henderson, Thomas B.; Drake, Barry L.; Bocker, Richard P.

    1986-09-01

    The modified signed-digit (MSD) number representation offers full parallel, carry-free addition. A MSD adder has been described by the authors. This paper describes how the adder can be used in a tree structure to implement an optical multiply algorithm. Three different optical schemes, involving position, polarization, and intensity encoding, are proposed for realizing the trinary logic system. When configured in the generic multiplier architecture, these schemes yield the combinatorial logic necessary to carry out the multiplication algorithm. The optical systems are essentially three dimensional arrangements composed of modular units. Of course, this modularity is important for design considerations, while the parallelism and noninterfering communication channels of optical systems are important from the standpoint of reduced complexity. The authors have also designed electronic hardware to demonstrate and model the combinatorial logic required to carry out the algorithm. The electronic and proposed optical systems will be compared in terms of complexity and speed.

  12. Multiplier method may be unreliable to predict the timing of temporary hemiepiphysiodesis for coronal angular deformity.

    Science.gov (United States)

    Wu, Zhenkai; Ding, Jing; Zhao, Dahang; Zhao, Li; Li, Hai; Liu, Jianlin

    2017-07-10

    The multiplier method was introduced by Paley to calculate the timing for temporary hemiepiphysiodesis. However, this method has not been verified in terms of clinical outcome measure. We aimed to (1) predict the rate of angular correction per year (ACPY) at the various corresponding ages by means of multiplier method and verify the reliability based on the data from the published studies and (2) screen out risk factors for deviation of prediction. A comprehensive search was performed in the following electronic databases: Cochrane, PubMed, and EMBASE™. A total of 22 studies met the inclusion criteria. If the actual value of ACPY from the collected date was located out of the range of the predicted value based on the multiplier method, it was considered as the deviation of prediction (DOP). The associations of patient characteristics with DOP were assessed with the use of univariate logistic regression. Only one article was evaluated as moderate evidence; the remaining articles were evaluated as poor quality. The rate of DOP was 31.82%. In the detailed individual data of included studies, the rate of DOP was 55.44%. The multiplier method is not reliable in predicting the timing for temporary hemiepiphysiodesis, even though it is prone to be more reliable for the younger patients with idiopathic genu coronal deformity.

  13. Multipliers for the Absolute Euler Summability of Fourier Series

    Indian Academy of Sciences (India)

    In this paper, the author has investigated necessary and sufficient conditions for the absolute Euler summability of the Fourier series with multipliers. These conditions are weaker than those obtained earlier by some workers. It is further shown that the multipliers are best possible in certain sense.

  14. Multiplier convergent series and uniform convergence of mapping ...

    Indian Academy of Sciences (India)

    MS received 14 April 2011; revised 17 November 2012. Abstract. In this paper, we introduce the frame property of complex sequence sets and study the uniform convergence of nonlinear mapping series in β-dual of spaces consisting of multiplier convergent series. Keywords. Multiplier convergent series; mapping series. 1.

  15. Dimension of the c-nilpotent multiplier of Lie algebras

    Indian Academy of Sciences (India)

    Abstract. The purpose of this paper is to derive some inequalities for dimension of the c-nilpotent multiplier of finite dimensional Lie algebras and their factor Lie algebras. We further obtain an inequality between dimensions of c-nilpotent multiplier of Lie algebra L and tensor product of a central ideal by its abelianized factor ...

  16. Influência do 1-MCP na conservação pós-colheita de rosas cv. Vega Influence of 1-MCP on postharvest conservation of roses cv. Vega

    Directory of Open Access Journals (Sweden)

    Júlia De Pietro

    2010-10-01

    Full Text Available Objetivou-se, neste trabalho, estudar aspectos da fisiologia pós-colheita de rosas cortadas cv. Vega, tratadas com diferentes concentrações de 1-metilcicloropropeno (1-MCP. O experimento foi conduzido em delineamento inteiramente casualizado, em esquema fatorial composto por dois fatores: quatro tratamentos pós-colheita e quatro datas de avaliação (0; 4; 8; 12 dias. As flores foram submetidas aos seguintes tratamentos: 1 Água destilada (controle; 2 1-MCP (100 ppb; 3 1-MCP (250 ppb; 4 1-MCP (500 ppb. Foram realizadas as seguintes avaliações: massa fresca, cor, turgescência, curvatura, taxa respiratória, conteúdo relativo de água, conteúdo de carboidratos solúveis, de redutores e de antocianina. Ao contrário do tratamento controle, todas as concentrações de 1-MCP foram eficientes para retardar a senescência das flores, porém, a concentração de 1-MCP a 500 ppb destacou-se pela melhor manutenção da qualidade, além de prolongar a vida decorativa das hastes até 19 dias.The objective of this work was to study aspects of postharvest physiology of cut roses cv. Vega, treated with different concentrations of 1-metilcloropropene (1-MCP. The experiment was conducted in a complete randomized design composed of two factors: four postharvest treatments and four dates of evaluation (0; 4; 8; 12 days. The following treatments were used: 1 distilled water; 2 1-metilciclopropeno (1-MCP 100 ppb; 3 1-MCP 250 ppb; 4 1-MCP 500 ppb. The following evaluations were made: fresh weight, color, turgor, curvature, respiration rate, relative water content, content of soluble carbohydrates, reducing and anthocyanin. Unlike treatment with distilled water, all concentrations of 1-MCP were effective in delaying the senescence of flowers; however, the concentration of 1-MCP at 500 ppb was highlighted by better maintenance of quality and extended decorate life stem up to 19 days.

  17. The role of MCP-1-CCR2 ligand-receptor axis in chondrocyte degradation and disease progress in knee osteoarthritis

    Directory of Open Access Journals (Sweden)

    Yuan-kun Xu

    Full Text Available BACKGROUND: Osteoarthritis (OA is a common arthritic disease and multifactorial whole-joint disease. Interactions of chemokines and OA is inadequately documented RESULTS: In vivo and in vitro studies were conducted to investigate monocyte chemoattractant protein 1 (MCP-1 and receptor chemokine (C-C motif receptor 2 (CCR2 in chondrocyte degradation and cartilage degeneration. Chondrocytes from 16 OA patients and 6 normal controls were involved in this study. After stimulation of MCP-1, the expression of MCP-1 and CCR2 increased significantly (P < 0.001 and the expression of MMP-13 also increased (P < 0.05. MCP-1 stimulation also induced (or enhanced the apoptosis of OA chondrocytes (P < 0.05. Additionally, the degradation of cartilage matrix markers (metalloproteinase 3 and 13, MMP3 and MMP13 in the culture medium of normal chondrocytes was also assessed. Furthermore, intra-articular injection of MCP-1 in mouse knees induced cartilage degradation and the CCR2 antagonist did not impede cartilage destroy in rats knees of monosodium iodoacetate (MIA model CONCLUSIONS: The results of this study demonstrate that the MCP-1-CCR2 ligand-receptor axis plays a special role in the initiation and progression of OA pathology. Patients with ambiguous etiology can gain some insight from the MCP-1-CCR2 ligand-receptor axis

  18. Silicon Photo-Multiplier Radiation Hardness Tests with a White Neutron Beam

    International Nuclear Information System (INIS)

    Montanari, A.; Tosi, N.; Pietropaolo, A.; Andreotti, M.; Baldini, W.; Calabrese, R.; Cibinetto, G.; Luppi, E.; Cotta Ramusino, A.; Malaguti, R.; Santoro, V.; Tellarini, G.; Tomassetti, L.; De Donato, C.; Reali, E.

    2013-06-01

    We report radiation hardness tests performed, with a white neutron beam, at the Geel Electron Linear Accelerator in Belgium on silicon Photo-Multipliers. These are semiconductor photon detectors made of a square matrix of Geiger-Mode Avalanche photo-diodes on a silicon substrate. Several samples from different manufacturers have been irradiated integrating up to about 6.2 x 10 9 1-MeV-equivalent neutrons per cm 2 . (authors)

  19. Charge exchange and ionization in atom-multiply-charged ion collisions

    International Nuclear Information System (INIS)

    Presnyakov, L.P.; Uskov, D.B.

    1988-01-01

    This study investigates one-electron transitions to the continuous and discrete spectra induced by a collision of atom A and multiply-charged ion B +Z with nuclear charge Z > 3. An analytical method is developed the charge-exchange reaction; this method is a generalization of the decay model and the approximation of nonadiabatic coupling of two states that are used as limiting cases in the proposed approach

  20. Influence of capture to excited states of multiply charged ion beams colliding with small molecules

    International Nuclear Information System (INIS)

    Montenegro, P; Monti, J M; Fojón, O A; Hanssen, J; Rivarola, R D

    2015-01-01

    Electron capture by multiply charged ions impacting on small molecules is theoretically investigated. Particular attention is paid to the case of biological targets. The interest is focused on the importance of the transition to excited final states which can play a dominant role on the total capture cross sections. Projectiles at intermediate and high collision energies are considered. Comparison with existing experimental data is shown. (paper)

  1. Optimizing strassen matrix multiply on GPUs

    KAUST Repository

    ul Hasan Khan, Ayaz; Al-Mouhamed, Mayez; Fatayer, Allam

    2015-01-01

    © 2015 IEEE. Many core systems are basically designed for applications having large data parallelism. Strassen Matrix Multiply (MM) can be formulated as a depth first (DFS) traversal of a recursion tree where all cores work in parallel on computing each of the NxN sub-matrices that reduces storage at the detriment of large data motion to gather and aggregate the results. We propose Strassen and Winograd algorithms (S-MM and W-MM) based on three optimizations: a set of basic algebra functions to reduce overhead, invoking efficient library (CUBLAS 5.5), and parameter-tuning of parametric kernel to improve resource occupancy. On GPUs, W-MM and S-MM with one recursion level outperform CUBLAS 5.5 Library with up to twice as faster for large arrays satisfying N>=2048 and N>=3072, respectively. Compared to NVIDIA SDK library, S-MM and W-MM achieved a speedup between 20x to 80x for the above arrays. The proposed approach can be used to enhance the performance of CUBLAS and MKL libraries.

  2. Optimizing strassen matrix multiply on GPUs

    KAUST Repository

    ul Hasan Khan, Ayaz

    2015-06-01

    © 2015 IEEE. Many core systems are basically designed for applications having large data parallelism. Strassen Matrix Multiply (MM) can be formulated as a depth first (DFS) traversal of a recursion tree where all cores work in parallel on computing each of the NxN sub-matrices that reduces storage at the detriment of large data motion to gather and aggregate the results. We propose Strassen and Winograd algorithms (S-MM and W-MM) based on three optimizations: a set of basic algebra functions to reduce overhead, invoking efficient library (CUBLAS 5.5), and parameter-tuning of parametric kernel to improve resource occupancy. On GPUs, W-MM and S-MM with one recursion level outperform CUBLAS 5.5 Library with up to twice as faster for large arrays satisfying N>=2048 and N>=3072, respectively. Compared to NVIDIA SDK library, S-MM and W-MM achieved a speedup between 20x to 80x for the above arrays. The proposed approach can be used to enhance the performance of CUBLAS and MKL libraries.

  3. Localization of monocyte chemotactic and activating factor (MCAF/MCP-1) in psoriasis

    DEFF Research Database (Denmark)

    Deleuran, M; Buhl, L; Ellingsen, T

    1996-01-01

    in the epidermal pustules in pustular psoriasis. In normals positive staining was observed in all the layers of the epidermis and in a few perivascular cells and blood vessels in the dermis. Where present in normal and diseased skin, eccrine ducts of sweat glands and sebaceous glands stained positive for MCAF......The monocyte chemotactic protein-1 (MCAF) also termed MCP-1, a strong chemotactic factor towards monocytes, is produced by several cell types present in the skin. The in situ presence of MCAF/MCP-1 protein in the skin has, however, not yet been established. Using immunohistochemical techniques we...... have investigated the distribution of MCAF in skin from patients with different types of psoriasis and normal healthy volunteers. We report the novel finding that psoriasis has strong positive immunostaining for MCAF located to all the layers of the epidermis, except the stratum granulosum, in pustular...

  4. Conservação da qualidade de caqui 'Fuyu' em ambiente refrigerado pela combinação de 1-MCP e atmosfera modificada Quality maintenance of 'Fuyu' persimmon in cold storage by combining 1-MCP and modified atmosphere

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Argenta

    2009-06-01

    Full Text Available O presente estudo analisou os efeitos do inibidor da ação do etileno 1-MCP (1-metilciclopropeno, da AM (atmosfera modificada e do oxidante de etileno KMnO4 (permanganato de potássio sobre a qualidade de caqui 'Fuyu' após a armazenagem refrigerada. Os fatores 1-MCP, AM e KMnO4 foram combinados de quatro maneiras, correspondendo aos seguintes tratamentos: T1 Controle + AM + KMnO4;T2 1-MCP + AM + KMnO4; T3 1-MCP + AM, e T4 1-MCP + AA (AA=atmosfera do ar. Frutos maduro-firmes com coloração da casca predominantemente amarela foram colhidos em sete pomares comerciais no nordeste do Estado do Rio Grande do Sul. Parte dos frutos foi exposta a 0.3 µL L-1 de 1-MCP por 12 h em 24 h após a colheita. A seguir, os frutos foram armazenados sob AA ou sob AM induzida por bolsas de polietileno (0,04 mm de espessura, por 20; 40; 60 ou 80 dias a -0,1±0,8ºC. Dois sachês contendo 8,5 g de Alumina-KMnO4foram adicionados em cada uma das bolsas de polietileno dos tratamentos um e dois, antes de elas serem vedadas. Os frutos de cada período de armazenagem refrigerada foram analisados após 0; 3; 6 ou 9 dias de prateleira sob AA a 22±1ºC. O tratamento 1-MCP retardou o amolecimento da polpa, mas não afetou consistentemente o desenvolvimento de 'estrias' e manchas pretas na superfície dos frutos armazenados sob AM contendo KMnO4. A incidência de 'estrias' e manchas pretas em frutos tratados com 1-MCP e armazenados sob AM foi significativamente menor que a de frutos tratados com 1-MCP e armazenados sob AA. Houve efeitos aditivos do 1-MCP e AM na conservação da firmeza e na redução de danos por frio manifestados pela formação de textura gel-firme e manchas translúcidas na casca. O uso de KMnO4 não aumentou a conservação da qualidade dos frutos quando tratados com 1-MCP e armazenados sob AM. O desenvolvimento dos distúrbios da epiderme dependeu do pomar e de períodos de armazenagem e prateleira. No entanto, os benefícios da combinação de 1-MCP e

  5. Role of human pulmonary fibroblast-derived MCP-1 in cell activation and migration in experimental silicosis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xueting [Department of Physiology, Medical School of Southeast University, Nanjing, Jiangsu 210009 (China); Fang, Shencun [Nine Department of Respiratory Medicine, Nanjing Chest Hospital, Nanjing, Jiangsu 210029 (China); Liu, Haijun [Neurobiology Laboratory, New Drug Screening Centre, China Pharmaceutical University, Nanjing, Jiangsu 210009 (China); Wang, Xingang; Dai, Xiaoniu; Yin, Qing; Yun, Tianwei [Department of Physiology, Medical School of Southeast University, Nanjing, Jiangsu 210009 (China); Wang, Wei; Zhang, Yingming [Nine Department of Respiratory Medicine, Nanjing Chest Hospital, Nanjing, Jiangsu 210029 (China); Liao, Hong [Neurobiology Laboratory, New Drug Screening Centre, China Pharmaceutical University, Nanjing, Jiangsu 210009 (China); Zhang, Wei [Department of Physiology, Medical School of Southeast University, Nanjing, Jiangsu 210009 (China); Yao, Honghong [Department of Pharmacology, Medical School of Southeast University, Nanjing, Jiangsu 210009 (China); Chao, Jie, E-mail: chaojie@seu.edu.cn [Department of Physiology, Medical School of Southeast University, Nanjing, Jiangsu 210009 (China)

    2015-10-15

    Background: Silicosis is a systemic disease caused by inhaling silicon dioxide (SiO{sub 2}). Phagocytosis of SiO{sub 2} in the lung initiates an inflammatory cascade that results in fibroblast proliferation and migration and subsequent fibrosis. Clinical evidence indicates that the activation of alveolar macrophages by SiO{sub 2} produces rapid and sustained inflammation that is characterized by the generation of monocyte chemotactic protein 1 (MCP-1), which induces fibrosis. Pulmonary fibroblast-derived MCP-1 may play a critical role in fibroblast proliferation and migration. Methods and results: Experiments using primary cultured adult human pulmonary fibroblasts (HPF-a) demonstrated the following results: 1) SiO{sub 2} treatment resulted in the rapid and sustained induction of MCP-1 as well as the elevation of the CC chemokine receptor type 2 (CCR2) protein levels; 2) pretreatment of HPF-a with RS-102895, a specific CCR2 inhibitor, abolished the SiO{sub 2}-induced increase in cell activation and migration in both 2D and 3D culture systems; and 3) RNA interference targeting CCR2 prevented the SiO{sub 2}-induced increase in cell migration. Conclusion: These data demonstrated that the up-regulation of pulmonary fibroblast-derived MCP-1 is involved in pulmonary fibroblast migration induced by SiO{sub 2}. CCR2 was also up-regulated in response to SiO{sub 2}, and this up-regulation facilitated the effect of MCP-1 on fibroblasts. Our study deciphered the link between fibroblast-derived MCP-1 and SiO{sub 2}-induced cell migration. This finding provides novel insight into the potential of MCP-1 in the development of novel therapeutic strategies for silicosis. - Highlights: • Role of pulmonary fibroblast-derived MCP-1 in experimental silicosis was studied. • SiO{sub 2} induced MCP-1 release from cultured human pulmonary fibroblast (HPF-a). • SiO{sub 2} directly activated HPF-a via the MCP-1/CCR2 pathway. • SiO{sub 2} increased HPF-a migration in both 2D and 3D

  6. Role of human pulmonary fibroblast-derived MCP-1 in cell activation and migration in experimental silicosis

    International Nuclear Information System (INIS)

    Liu, Xueting; Fang, Shencun; Liu, Haijun; Wang, Xingang; Dai, Xiaoniu; Yin, Qing; Yun, Tianwei; Wang, Wei; Zhang, Yingming; Liao, Hong; Zhang, Wei; Yao, Honghong; Chao, Jie

    2015-01-01

    Background: Silicosis is a systemic disease caused by inhaling silicon dioxide (SiO 2 ). Phagocytosis of SiO 2 in the lung initiates an inflammatory cascade that results in fibroblast proliferation and migration and subsequent fibrosis. Clinical evidence indicates that the activation of alveolar macrophages by SiO 2 produces rapid and sustained inflammation that is characterized by the generation of monocyte chemotactic protein 1 (MCP-1), which induces fibrosis. Pulmonary fibroblast-derived MCP-1 may play a critical role in fibroblast proliferation and migration. Methods and results: Experiments using primary cultured adult human pulmonary fibroblasts (HPF-a) demonstrated the following results: 1) SiO 2 treatment resulted in the rapid and sustained induction of MCP-1 as well as the elevation of the CC chemokine receptor type 2 (CCR2) protein levels; 2) pretreatment of HPF-a with RS-102895, a specific CCR2 inhibitor, abolished the SiO 2 -induced increase in cell activation and migration in both 2D and 3D culture systems; and 3) RNA interference targeting CCR2 prevented the SiO 2 -induced increase in cell migration. Conclusion: These data demonstrated that the up-regulation of pulmonary fibroblast-derived MCP-1 is involved in pulmonary fibroblast migration induced by SiO 2 . CCR2 was also up-regulated in response to SiO 2 , and this up-regulation facilitated the effect of MCP-1 on fibroblasts. Our study deciphered the link between fibroblast-derived MCP-1 and SiO 2 -induced cell migration. This finding provides novel insight into the potential of MCP-1 in the development of novel therapeutic strategies for silicosis. - Highlights: • Role of pulmonary fibroblast-derived MCP-1 in experimental silicosis was studied. • SiO 2 induced MCP-1 release from cultured human pulmonary fibroblast (HPF-a). • SiO 2 directly activated HPF-a via the MCP-1/CCR2 pathway. • SiO 2 increased HPF-a migration in both 2D and 3D model via the MCP-1/CCR2 pathway. • RNA-i of MCP-1/CCR2

  7. Role of MCP-1 in pleural effusion development in a carrageenan-induced murine model of pleurisy.

    Science.gov (United States)

    Lansley, Sally M; Cheah, Hui Min; Lee, Y C Gary

    2017-05-01

    Exudative pleural effusions affect over 1500 patients per million population each year. The pathobiology of pleural exudate formation remains unclear. Our recent study revealed monocyte chemotactic protein-1 (MCP-1) as a key driver of fibrinolytic-induced exudate effusion while another study found a role for MCP-1 in malignant effusion formation. In the present study, we further evaluated the role of MCP-1 in the development of pleural effusion in a mouse model of acute pleural inflammation. λ-Carrageenan (CAR) was injected into the pleural cavity of CD1 mice and pleural effusion volume measured up to 16 h post-injection. Pleural effusion and serum protein and MCP-1 concentrations were measured and differential cell counts performed in fluids. Mice were also treated with either intraperitoneal (i) anti-MCP-1 antibody or isotype control or (ii) an MCP-1 receptor (CCR2) antagonist or vehicle control 12 h prior to and at the time of CAR injection. Intrapleural CAR induced significant pleural fluid accumulation (300.0 ± 49.9 μL) in mice after 4 h. Pleural fluid MCP-1 concentrations were significantly higher than corresponding serum MCP-1 (144 603 ± 23 204 pg/mL vs 3703 ± 801 pg/mL, P pleural fluid formation was seen both with anti-MCP-1 antibody (median (interquartile range, IQR): 36 (0-168) μL vs controls 290 (70-436) μL; P = 0.02) or CCR2 antagonist (153 (30-222) μL vs controls 240 (151-331) μL, P = 0.0049). Blockade of MCP-1 activity significantly reduced inflammatory pleural effusion formation in a CAR model. Together with recent successes in MCP-1 blockade in other effusion formation models, our data strongly support clinical evaluation of MCP-1 antagonists as a novel approach to pleural fluid management. © 2016 Asian Pacific Society of Respirology.

  8. EFECTO DEL 1-METIL-CICLOPROPENO (1-MCP EN LA MADURACIÓN DE BANANO

    Directory of Open Access Journals (Sweden)

    Kattia Chang-Yuen

    2005-01-01

    Full Text Available Se evaluó la eficacia del 1-metil-ciclopropeno (1-MCP en la maduración del banano (Musa sp Cavendish, aplicado después del empaque en fruta para el mercado de EE.UU. y Europa. Se utilizó fruta de 3 diferentes compañías bananeras; la fruta fue expuesta a 0, 20 y 30 nl l-1 de 1-MCP, por 24 h. Posteriormente, fue sometida a simulación de transporte, según el mercado de destino (7 días EE.UU. y 15 días Europa. Finalizada la simulación se indujo el proceso de maduración con etileno. Las evaluaciones se realizaron cada 2 días, e incluyeron análisis de calidad externa (enfermedades poscosecha y desarrollo de color externo de la cáscara y de calidad interna (oBrix, firmeza, porcentaje de acidez titulable y tasa de produc ción de CO2. Una aplicación de 30 nl l-1 de 1-MCP, generó una ganancia de más de 4 días de vida de anaquel por encima de la fruta control.La apariencia externa y la calidad interna de la fruta no se vio afectada de forma negativa por la exposición al 1-MCP, aunque se recomienda realizar pruebas sensoriales con consumidores en los mercados de destino.

  9. State of art report for high temperature wear test of SMART MCP and CEDM bearing material

    International Nuclear Information System (INIS)

    Cho, Yong Hu; Lee, Jae Seon; Park, Jin Seok; Kim, Ji Ho; Kim, Jong In

    2000-03-01

    Wear resistance properties of machine elements has been more critical in view of its significant effect on life extension, economics and material saving because it has been recognized that nearly 80 percent of damages of mechanical elements in the friction pairs are due to the material loss by wear. And wear properties have direct influence on the life of a machine in a great extend under extremely severe operating condition. Therefore highly improved wear properties of machine elements operating in such circumstances is heavily required. The purpose of this report is to survey current technology for high temperature wear test in order to establish the test plan for the life evaluation of SMART MCP and CEDM bearing materials. Friction and wear test will be done under high pressure (170 MPa) and high temperature (350 degree C) with water as lubricant to simulate the operating condition of the nuclear power reactor. Because pump type for MCP is selected as the caned motor pump which needs no mechanical sealing, the rotating shaft on which bearing is fully submerged by main coolant with high temperature. So MCP bearing operates without additional lubricant. CEDM is adopted as the ball-screw type with fine controllability. So the driving part is designed as the immersed-in type by main coolant. Therefore the anti-wear and reliability of driving parts are much consequent to guarantee the lifetime and the safety of the whole system. Tribometer adapted to high temperature and pressure circumstance is needed to execute bearing material testing. Test parameters are material, sliding speed, sliding distance and applied load. In order to identify the wear mechanism, optical microscope and surface roughness testers are required. The result of this report will provide an elementary data to develop bearing materials and to estimate bearing lifetime for the bearings of MCP and CEDM in SMART. (author)

  10. Ethylene and 1-MCP regulate major volatile biosynthetic pathways in apple fruit.

    Science.gov (United States)

    Yang, Xiaotang; Song, Jun; Du, Lina; Forney, Charles; Campbell-Palmer, Leslie; Fillmore, Sherry; Wismer, Paul; Zhang, Zhaoqi

    2016-03-01

    The effects of ethylene and 1-methylcyclopropene (1-MCP) on apple fruit volatile biosynthesis and gene expression were investigated. Statistical analysis identified 17 genes that changed significantly in response to ethylene and 1-MCP treatments. Genes encoding branched-chain amino acid aminotransferase (BCAT), aromatic amino acid aminotransferase (ArAT) and amino acid decarboxylases (AADC) were up-regulated during ripening and further enhanced by ethylene treatment. Genes related to fatty acid synthesis and metabolism, including acyl-carrier-proteins (ACPs), malonyl-CoA:ACP transacylase (MCAT), acyl-ACP-desaturase (ACPD), lipoxygenase (LOX), hydroperoxide lyase (HPL), alcohol dehydrogenase (ADH), pyruvate decarboxylase (PDC2), β-oxidation, acyl-CoA synthetase (ACS), enoyl-CoA hydratase (ECHD), acyl-CoA dehydrogenase (ACAD), and alcohol acyltransferases (AATs) also increased during ripening and in response to ethylene treatment. Allene oxide synthase (AOS), alcohol dehydrogenase 1 (ADH1), 3-ketoacyl-CoA thiolase and branched-chain amino acid aminotransferase 2 (BCAT2) decreased in ethylene-treated fruit. Treatment with 1-MCP and ethylene generally produced opposite effects on related genes, which provides evidence that regulation of these genes is ethylene dependent. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  11. The cross-validated AUC for MCP-logistic regression with high-dimensional data.

    Science.gov (United States)

    Jiang, Dingfeng; Huang, Jian; Zhang, Ying

    2013-10-01

    We propose a cross-validated area under the receiving operator characteristic (ROC) curve (CV-AUC) criterion for tuning parameter selection for penalized methods in sparse, high-dimensional logistic regression models. We use this criterion in combination with the minimax concave penalty (MCP) method for variable selection. The CV-AUC criterion is specifically designed for optimizing the classification performance for binary outcome data. To implement the proposed approach, we derive an efficient coordinate descent algorithm to compute the MCP-logistic regression solution surface. Simulation studies are conducted to evaluate the finite sample performance of the proposed method and its comparison with the existing methods including the Akaike information criterion (AIC), Bayesian information criterion (BIC) or Extended BIC (EBIC). The model selected based on the CV-AUC criterion tends to have a larger predictive AUC and smaller classification error than those with tuning parameters selected using the AIC, BIC or EBIC. We illustrate the application of the MCP-logistic regression with the CV-AUC criterion on three microarray datasets from the studies that attempt to identify genes related to cancers. Our simulation studies and data examples demonstrate that the CV-AUC is an attractive method for tuning parameter selection for penalized methods in high-dimensional logistic regression models.

  12. Ethylene and 1-MCP affect the postharvest behavior of yellow pitahaya fruits (Selenicereus megalanthus Haw.

    Directory of Open Access Journals (Sweden)

    Yuli Alexandra Deaquiz

    2014-04-01

    Full Text Available The pitahaya or dragon fruit is one of the most representative exotic fruits that Colombia has, with an important, growing international market, but the cultivation and postharvest of this fruit lack sufficient technological support to be more competitive. Therefore, alternatives that provide good-quality products that meet market requirements are very important. Therefore, the objective of this research was to determine the effect of a ripening retardant and ethylene application on the conservation and quality of pitahaya fruits and the possible changes during ripening associated with ethylene, for which a completely randomized design with three treatments was used, corresponding to the application of ethylene (ethephon, 3 mL L-1, 1-methylcyclopropene (1-MCP, 600 mg L-1 and a control, with four replications, for a total of 12 experimental units. The fruits were stored at 18°C with 75% relative humidity. The 1-MCP application significantly decreased the loss of firmness, total soluble solids, loss of fresh mass and respiratory rate. Fruits from the control and ethylene treatment tended toward a climateric respiratory behavior. The total carotenoid content of the fruits was significantly higher in the ethylene application and the control treatment, which was consistent with the color change of the fruits. It can be concluded that the 1-MCP application reduced the ethylene action, slowing the ripening of the dragon fruits.

  13. Electronic structure of elements and compounds and electronic phases of solids

    International Nuclear Information System (INIS)

    Nadykto, B.A.

    2000-01-01

    The paper reviews technique and computed energies for various electronic states of many-electron multiply charged ions, molecular ions, and electronic phases of solids. The model used allows computation of the state energy for free many-electron multiply charged ions with relative accuracy ∼10 -4 suitable for analysis of spectroscopy data

  14. Design of two easily-testable VLSI array multipliers

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, J.; Shen, J.P.

    1983-01-01

    Array multipliers are well-suited to VLSI implementation because of the regularity in their iterative structure. However, most VLSI circuits are very difficult to test. This paper shows that, with appropriate cell design, array multipliers can be designed to be very easily testable. An array multiplier is called c-testable if all its adder cells can be exhaustively tested while requiring only a constant number of test patterns. The testability of two well-known array multiplier structures are studied. The conventional design of the carry-save array multipler is shown to be not c-testable. However, a modified design, using a modified adder cell, is generated and shown to be c-testable and requires only 16 test patterns. Similar results are obtained for the baugh-wooley two's complement array multiplier. A modified design of the baugh-wooley array multiplier is shown to be c-testable and requires 55 test patterns. The implementation of a practical c-testable 16*16 array multiplier is also presented. 10 references.

  15. Analytical theory of frequency-multiplying gyro-traveling-wave-tubes

    International Nuclear Information System (INIS)

    Nusinovich, G.S.; Chen, W.; Granatstein, V.L.

    2001-01-01

    The theory is developed which describes analytically the gain and bandwidth in frequency-multiplying gyro-traveling-wave-tubes. In this theory the input waveguide is considered in the small-signal approximation. Then, in the drift region separating the input and output waveguides, the electron ballistic bunching evolves which causes the appearance in the electron current density of the harmonics of the signal frequency. The excitation of the output waveguide by one of these harmonics is considered in a specified current approximation. This makes the analytical study of a large-signal operation possible. The theory is illustrated by using it to analyze the performance of an existing experimental tube

  16. Confinement of multiply charged ions in an ECRH mirror plasma

    International Nuclear Information System (INIS)

    Petty, C.C.

    1989-06-01

    This thesis is an experimental study of multiply charged ions in the Constance B mirror experiment. By measuring the ion densities, end loss fluxes and ion temperatures, the parallel confinement times for the first five charge states of oxygen and neon plasmas are determined. The parallel ion confinement times increase with charge state and peak on axis, both indications of an ion-confining potential dip created by the hot electrons. The radial profile of ion end loss is usually hollow due to large ion radial transport (τ paralleli ∼ τ perpendiculari ), with the peak fluxes occurring at the edge of the electron cyclotron resonance zone. Several attempts are made to increase the end loss of selected ion species. Using minority ICRH, the end loss flux of resonant ions increases by 20% in cases when radial transport induced by ICRH is not too severe. A large antenna voltage can also extinguish the plasma. By adding helium to an oxygen plasma, the end loss of O 6+ increases by 80% due to decreased ion radial transport. An ion model is developed to predict the ion densities, end loss fluxes and confinement times in the plasma center using the ion particle balance equations, the quasineutrality condition and theoretical confinement time formulas. The model generally agrees with the experimental data for oxygen and neon plasmas to within experimental error. Under certain conditions spatial diffusion appears to determine the parallel ion confinement time of the highest charge states. For oxygen plasmas during ICRH, the measured parallel confinement time of the resonant ions is much shorter than their theoretical value, probably due to rf diffusion of the ions into the loss cone. 58 refs., 101 figs., 16 tabs

  17. An overview of current developments in position-sensitive hybrid photon detectors and photo-multiplier tubes

    CERN Document Server

    Gys, Thierry

    1999-01-01

    Current developments in position-sensitive hybrid photon detectors and photo-multiplier tubes have stimulated increased interest from a variety of fields such as astronomy, biomedical imaging and high- energy physics. These devices are sensitive to single photons over a photon energy spectrum defined by the transmission of the optical entrance window and the photo-cathode type. Their spatial resolution ranges from a few millimeters for pad hybrid photon detectors and multi-anode photo-multiplier tubes down to a few tens of microns for pixel hybrid photon detectors and electron-bombarded charge-coupled devices. Basic technological and design aspects are assessed in this paper. (21 refs).

  18. Photoionization of multiply charged ions at the advanced light source

    International Nuclear Information System (INIS)

    Schlachter, A.S.; Kilcoyne, A.L.D.; Aguilar, A.; Gharaibeh, M.F.; Emmons, E.D.; Scully, S.W.J.; Phaneuf, R.A.; Muller, A.; Schippers, S.; Alvarez, I.; Cisneros, C.; Hinojosa, G.; McLaughlin, B.M.

    2004-01-01

    Photoionization of multiply charged ions is studied using the merged-beams technique at the Advanced Light Source. Absolute photoionization cross sections have been measured for a variety of ions along both isoelectronic and isonuclear sequences

  19. Cavallo's multiplier for in situ generation of high voltage

    Science.gov (United States)

    Clayton, S. M.; Ito, T. M.; Ramsey, J. C.; Wei, W.; Blatnik, M. A.; Filippone, B. W.; Seidel, G. M.

    2018-05-01

    A classic electrostatic induction machine, Cavallo's multiplier, is suggested for in situ production of very high voltage in cryogenic environments. The device is suitable for generating a large electrostatic field under conditions of very small load current. Operation of the Cavallo multiplier is analyzed, with quantitative description in terms of mutual capacitances between electrodes in the system. A demonstration apparatus was constructed, and measured voltages are compared to predictions based on measured capacitances in the system. The simplicity of the Cavallo multiplier makes it amenable to electrostatic analysis using finite element software, and electrode shapes can be optimized to take advantage of a high dielectric strength medium such as liquid helium. A design study is presented for a Cavallo multiplier in a large-scale, cryogenic experiment to measure the neutron electric dipole moment.

  20. Sociophysics of sexism: normal and anomalous petrie multipliers

    Science.gov (United States)

    Eliazar, Iddo

    2015-07-01

    A recent mathematical model by Karen Petrie explains how sexism towards women can arise in organizations where male and female are equally sexist. Indeed, the Petrie model predicts that such sexism will emerge whenever there is a male majority, and quantifies this majority bias by the ‘Petrie multiplier’: the square of the male/female ratio. In this paper—emulating the shift from ‘normal’ to ‘anomalous’ diffusion—we generalize the Petrie model to a stochastic Poisson model that accommodates heterogeneously sexist men and woman, and that extends the ‘normal’ quadratic Petrie multiplier to ‘anomalous’ non-quadratic multipliers. The Petrie multipliers span a full spectrum of behaviors which we classify into four universal types. A variation of the stochastic Poisson model and its Petrie multipliers is further applied to the context of cyber warfare.

  1. Atomic collisions in fusion plasmas involving multiply charged ions

    International Nuclear Information System (INIS)

    Salzborn, E.

    1980-01-01

    A short survey is given on atomic collisions involving multiply charged ions. The basic features of charge transfer processes in ion-ion and ion-atom collisions relevant to fusion plasmas are discussed. (author)

  2. Efek Multiplier Zakat Terhadap Pendapatan di Propinsi DKI Jakarta

    Directory of Open Access Journals (Sweden)

    M. Nur Rianto Al Arif

    2015-10-01

    Full Text Available The aim of this research is to analyze the multiplier effect of zakah revenue in DKI Jakarta, a study case at Badan Amil Zakat, Infak, and Shadaqah (BAZIS DKI Jakarta. Least square methods is used to analyze the data. The coefficient will be used to calculate the multiplier effect of zakah revenue and it will be compared with the economy without zakah revenue. The result showed 2,522 multiplier effects of zakah revenue and 3,561 multiplier effect of economic income without zakah revenue. This suggest that the management of zakah in BAZIS DKI Jakarta still can have a significant influence on the economyDOI: 10.15408/aiq.v4i1.2079

  3. Multiplier less high-speed squaring circuit for binary numbers

    Science.gov (United States)

    Sethi, Kabiraj; Panda, Rutuparna

    2015-03-01

    The squaring operation is important in many applications in signal processing, cryptography etc. In general, squaring circuits reported in the literature use fast multipliers. A novel idea of a squaring circuit without using multipliers is proposed in this paper. Ancient Indian method used for squaring decimal numbers is extended here for binary numbers. The key to our success is that no multiplier is used. Instead, one squaring circuit is used. The hardware architecture of the proposed squaring circuit is presented. The design is coded in VHDL and synthesised and simulated in Xilinx ISE Design Suite 10.1 (Xilinx Inc., San Jose, CA, USA). It is implemented in Xilinx Vertex 4vls15sf363-12 device (Xilinx Inc.). The results in terms of time delay and area is compared with both modified Booth's algorithm and squaring circuit using Vedic multipliers. Our proposed squaring circuit seems to have better performance in terms of both speed and area.

  4. Instructional Computing Project Uses "Multiplier Effect" to Train Florida Teachers.

    Science.gov (United States)

    Roblyer, M. D.; Castine, W. H.

    1987-01-01

    Reviews the efforts undertaken in the Florida Model Microcomputer Trainer Project (FMMTP) and its statewide impact. Outlines its procedural strategies, trainer curriculum, networking system, and the results of its multiplier effect. (ML)

  5. EFEK MULTIPLIER ZAKAT TERHADAP PENDAPATAN DI PROVINSI DKI JAKARTA

    Directory of Open Access Journals (Sweden)

    M. Nur Rianto Al Arif

    2016-02-01

    Full Text Available The aim of this research is to analyse the multiplier effect of zakâh revenue in DKI Jakarta. A study case at Badan Amil Zakat, Infak, and Sadaqah (BAZIS DKI Jakarta. Least square method is used to analyze the data. The coefficients will be used to calculate the multiplier effect of zakâh-revenue and it will  be compared with the economy without zakah revenue. The results showed 2,522 multiplier effects of zakâh-revenue and 3.561 multiplier effect ofeconomic income without zakâh-revenue. This suggests that the management of zakat in BAZIS Jakarta still can have a significant influence on the economy.DOI: 10.15408/aiq.v4i1.2533

  6. The generalization of the Schur multipliers of Bieberbach groups

    Science.gov (United States)

    Masri, Rohaidah; Hassim, Hazzirah Izzati Mat; Sarmin, Nor Haniza; Ali, Nor Muhainiah Mohd; Idrus, Nor'ashiqin Mohd

    2014-12-01

    The Schur multiplier is the second homology group of a group. It has been found to be isomorphic to the kernel of a homomorphism which maps the elements in the exterior square of the group to the elements in its derived subgroup. Meanwhile, a Bieberbach group is a space group which is a discrete cocompact group of isometries of oriented Euclidean space. In this research, the Schur multipliers of Bieberbach groups with cyclic point group of order two of finite dimension are computed.

  7. Physics of subcritical multiplying regions and experimental validation

    International Nuclear Information System (INIS)

    Salvatores, M.

    1996-01-01

    The coupling of a particle accelerator with a spallation target and with a subcritical multiplying region has been proposed in the fifties and is called here a hybrid system. This article gives some ideas about the energetic balance of such a system. The possibilities of experimental validation of some properties of a subcritical multiplying region by using MASURCA facility at CEA-Cadarache are examined. The results of a preliminary experiment called MUSE are presented. (A.C.)

  8. Isometric multipliers of a vector valued Beurling algebra on a ...

    Indian Academy of Sciences (India)

    Throughout, let S be a nonunital faith- ful abelian semigroup, and let A be a commutative Banach algebra. A map σ : S → S is a multiplier [1, 4] if σ(xy) = xσ(y) = σ(x)y, x,y ∈ S. Let M(S) be the set of all multipliers of S. Then M(S) is a unital abelian semigroup under composition. Since S is faithful, S can be imbedded as an ...

  9. Mean secondary electron yield of avalanche electrons in the channels of a microchannel plate detector

    International Nuclear Information System (INIS)

    Funsten, H.O.; Suszcynsky, D.M.; Harper, R.W.

    1996-01-01

    By modeling the statistical evolution of an avalanche created by 20 keV protons impacting the input surface of a z-stack microchannel plate (MCP) detector, the mean secondary electron yield γ C of avalanche electrons propagating through a MCP channel is measured to equal 1.37 for 760 V per MCP in the z stack. This value agrees with other studies that used MCP gain measurements to infer γ C . The technique described here to measure γ C is independent of gain saturation effects and simplifying assumptions used in the segmented dynode model, both of which can introduce errors when inferring γ C through gain measurements. copyright 1996 American Institute of Physics

  10. Cluster-assistant generation of multiply charged atomic ions in nanosecond laser ionization of seeded methyl iodide beam

    International Nuclear Information System (INIS)

    Luo Xiaolin; Niu Dongmei; Kong Xianglei; Wen Lihua; Liang Feng; Pei Kemei; Wang Bin; Li Haiyang

    2005-01-01

    The photoionization of methyl iodide beam seeded in argon and helium is studied by time-of-flight mass spectrometry using a 25 ns, 532 nm Nd-YAG laser with intensities in the range of 2 x 10 10 -2 x 10 11 W/cm 2 . Multiply charged ions of I q+ (q = 2-3) and C 2+ with tens of eV kinetic energies have been observed when laser interacts with the middle part of the pulsed molecular beam, whose peak profiles are independent on the laser polarization directions. Strong evidences show that these ions are coming from the Coulomb explosion of multiply charged CH 3 I clusters, and laser induced inverse bremsstrahlung absorption of caged electrons plays a key role in the formation of multiply charged ions

  11. Experiment study on the thick GEM-like multiplier for X-ray photoelectrons energy deposition gaining

    International Nuclear Information System (INIS)

    Zhu Pengfei; Ye Yan; Long Yan; Cao Ningxiang; Jia Xing; Li Jianfeng

    2009-01-01

    The GEM is a novel detector with high gain,high time and location resolution. Imitating the structure of the GEM, a thick GEM-like multiplier which has the similar function with that of the GEM is designed and manufactured. The characteristics of the thick GEM-like multiplier increasing electron energy deposition in absorbing medium has been experimentally studied. The results indicate that the energy deposition gain of x-ray photoelectron in medium is apparent, and the maximum energy deposition can increase by more than 40%. Some suggestions of further increasing the energy deposition are given, and the future application of the way of increasing the x-ray photoelectron energy deposition by the thick GEM-like multiplier in hard x-ray imaging is prospected. (authors)

  12. Phenolic excipients of insulin formulations induce cell death, pro-inflammatory signaling and MCP-1 release

    Directory of Open Access Journals (Sweden)

    Claudia Weber

    2015-01-01

    Insulin solutions displayed cytotoxic and pro-inflammatory potential caused by phenol or m-cresol. We speculate that during insulin pump therapy phenol and m-cresol might induce cell death and inflammatory reactions at the infusion site in vivo. Inflammation is perpetuated by release of MCP-1 by activated monocytic cells leading to enhanced recruitment of inflammatory cells. To minimize acute skin complications caused by phenol/m-cresol accumulation, a frequent change of infusion sets and rotation of the infusion site is recommended.

  13. Physical, chemical and sensory changes of refrigerated yellow pitahaya treated preharvest with 1-MCP

    OpenAIRE

    Liliana Serna Cock; Laura Sofía Torres Valenzuela; Alfredo Ayala Aponte

    2013-01-01

    El efecto de la aplicación de soluciones acuosas de 0, 200 y 400 mg L de 1-metilciclopropeno (1-MCP) en pitahaya amarilla en precosecha (Selenicereus megalanthus Haw) fue evaluado. Se midieron los cambios en pérdida de peso, cambio total de la coloración, azucares totales, acidez titulable, ácido ascórbico y análisis sensorial. La pitahaya fue almacenada bajo refrigeración (10°C y 85% de humedad relativa por 29 días). Dos tipos de empaque (Cajas para exportación y canastillas plá...

  14. Features of destruction of solids by laser radiation in process of formation of multiply charged ions

    International Nuclear Information System (INIS)

    Bedilov, R.M.; Bedilov, M.R.; Sabitov, M.M.; Matnazarov, A.; Niyozov, B.

    2004-01-01

    Full text: It is known, under interaction of laser radiation with solid surface a power density q > 0.01 W/cm 2 are observed destruction of a solid and issue of electrons, ions, neutrals, neutrons, plasmas, and also radiation in a wide ranges of a spectra. Despite of a plenty of works, devoted to study of processes of interaction, the studies of feature of destruction of solids by laser beam in process of formation multiply charged ions are insufficiently investigated. The results of study feature of destruction of solids by laser radiation in process of formation multiply charged ions are given in this work. In our experiments, we used the mass spectrometer with single-channel laser radiation. The laser installation had the following parameters: a power density of laser radiation q=(0.1-50) GW/cm 2 ; the angle of incidence a=18 deg. to the target surface Al, (W). It was obtained experimentally dynamics of morphology of destruction and also mass - charge and energy spectra of multiply charged ions formed under interaction of laser radiation with Al (W) in the intensity range q=(0.1-50) GW/cm 2 . These studies showed features of destruction Al(W) by laser radiation, i.e. invariable of value evaporation mass from a surface of a solid increase as the laser intensity q. But thus temperature a pair increases in accordance with increase of flow density of a laser radiation. Increase of temperature the pair gives in formation of multiply charged plasma. It is typical that, as q of the laser increases the maximum charge number of ions in laser plasma considerably increase and their energy spectra extend toward higher energies. For example, under q=0.1 GW/cm 2 and 50 GW/cm 2 the maximum charge number of ions Al (W) are equal to Z max = 1 and 7, respectively. From the experimental data obtained, we can conclude that, the formed multiply charged plasma practically completely absorption laser radiation and 'shielding' a target surface for various metals at power densities

  15. Temporal cascade of inflammatory cytokines and cell-type populations in monocyte chemotactic protein-1 (MCP-1)-mediated aneurysm healing.

    Science.gov (United States)

    Hoh, Brian L; Fazal, Hanain Z; Hourani, Siham; Li, Mengchen; Lin, Li; Hosaka, Koji

    2018-03-01

    We have previously shown that monocyte chemotactic protein-1 (MCP-1) promotes aneurysm healing. To determine the temporal cascade and durability of aneurysm healing. Murine carotid aneurysms were treated with MCP-1-releasing or poly(lactic-co-glycolic) acid (PLGA)-only coils. Aneurysm healing was assessed by quantitative measurements of intraluminal tissue ingrowth on 5 μm sections by blinded observers. Aneurysm healing occurred in stages characteristic of normal wound healing. The 1st stage (day 3) was characterized by a spike in neutrophils and T cells. The 2nd stage (week 1) was characterized by an influx of macrophages and CD45+ cells significantly greater with MCP-1 than with PLGA (p<0.05). The third stage (week 2-3) was characterized by proliferation of smooth muscle cells and fibroblasts (greater with MCP-1 than with PLGA, p<0.05). The fourth stage (3-6 months) was characterized by leveling off of smooth muscle cells and fibroblasts. M1 macrophages were greater at week 1, whereas M2 macrophages were greater at weeks 2 and 3 with MCP-1 than with PLGA. Interleukin 6 was present early and increased through week 2 (p<0.05 compared with PLGA) then decreased and leveled off through 6 months. Tumour necrosis factor α was present early and remained constant through 6 months. MCP-1 and PLGA treatment had similar rates of tissue ingrowth at early time points, but MCP-1 had a significantly greater tissue ingrowth at week 3 (p<0.05), which persisted for 6 months. The sequential cascade is consistent with an inflammatory model of injury, repair, and remodeling. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  16. The roles of MCP-1 and protein kinase C delta activation in human eosinophilic leukemia EoL-1 cells.

    Science.gov (United States)

    Lee, Ji-Sook; Yang, Eun Ju; Kim, In Sik

    2009-12-01

    Idiopathic hypereosinophilc syndrome is a disorder associated with clonally eosinophilic proliferation. The importance of FIP1-like-1-platelet-derived growth factor receptor-alpha (FIP1L1-PDGFRA) in the pathogenesis and classification of HES has been recently reported. In this study, we investigated the contribution of monocyte chemoattractant protein-1 (MCP-1)/CCL2 to chemotactic activity and protein kinase C delta (PKC delta in the human eosinophilic leukemia cell line EoL-1. These cells express CCR2 protein among the CC chemokine receptors (CCR1-5). MCP-1 induces strong migration of EoL-1 cells and the chemotaxis signal in response to MCP-1 involves a G(i)/G(o) protein, phospholipase C (PLC), PKC delta, p38 MAPK and NF-kappaB. MCP-1 activates p38 MAPK via G(i)/G(o) protein, PLC and PKC delta cascade. MCP-1 also induces NF-kappaB translocation and the activation is inhibited by PKC delta activation. The increase in the basal expression and activity of PKC delta in EoL-1 cells, compared to normal eosinophils, inhibits apoptosis in EoL-1 cells. Anti-apoptotic mechanism of PKC delta is related to inhibition of caspase 3 and caspase 9, but not to FIP1L1-PDGFRA. PKC delta functions as an anti-apoptotic molecule, and is involved in EoL-1 cell movement stimulated by MCP-1. This study contributes to an understanding of MCP-1 in eosinophil biology and pathogenic mechanism of eosinophilic disorders.

  17. Myocardial production and release of MCP-1 and SDF-1 following myocardial infarction: differences between mice and man

    Directory of Open Access Journals (Sweden)

    Palasubramaniam Dharshan

    2011-09-01

    Full Text Available Abstract Background Stem cell homing to the heart is mediated by the release of chemo-attractant cytokines. Stromal derived factor -1 alpha (SDF-1a and monocyte chemotactic factor 1(MCP-1 are detectable in peripheral blood after myocardial infarction (MI. It remains unknown if they are produced by, and released from, the heart in order to attract stem cells to repair the damaged myocardium. Methods Murine hearts were studied for expression of MCP-1 and SDF-1a at day 3 and day 28 following myocardial infarction to determine whether production is increased following MI. In addition, we studied the coronary artery and coronary sinus (venous blood from patients with normal coronary arteries, stable coronary artery disease (CAD, unstable angina and MI to determine whether these cytokines are released from the heart into the systemic circulation following MI. Results Both MCP-1 and SDF-1a are constitutively produced and released by the heart. MCP-1 mRNA is upregulated following murine experimental MI, but SDF-1a is suppressed. There is less release of SDF-1a into the systemic circulation in patients with all stages of CAD including MI, mimicking the animal model. However MCP-1 release from the human heart following MI is also suppressed, which is the exact opposite of the animal model. Conclusions SDF-1a and MCP-1 release from the human heart are suppressed following MI. In the case of SDF-1a, the animal model appropriately reflects the human situation. However, for MCP-1 the animal model is the exact opposite of the human condition. Human observational studies like this one are paramount in guiding translation from experimental studies to clinical trials.

  18. Atraso do amadurecimento de banana 'Maçã' pelo 1-MCP, aplicado previamente à refrigeração Ripening delay of 'Apple' banana submitted to 1-MCP, prevoiously applied to refrigeration

    Directory of Open Access Journals (Sweden)

    Gustavo Costa Almeida

    2006-08-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de diferentes períodos de exposição da banana 'Maçã' a 50 ppb de 1-MCP (0; 3; 6; 9; 12 e 24 horas sobre sua vida pós-colheita e qualidade. Após exposição ao 1-MCP, os frutos verde-maturos foram armazenados por 30 dias em câmaras com temperatura de 13ºC ± 0,5 e umidade relativa de 95%. Em seguida, as bananas foram armazenadas à temperatura de 20ºC ± 1, até amarelecimento completo da casca. A exposição de banana 'Maçã' a 50 ppb de 1-MCP, por 9 horas, retardou em 7 dias o seu amadurecimento, em comparação a frutos não expostos ao 1-MCP, após 30 dias de armazenamento refrigerado (13ºC, sem prejuízos à sua aparência e composição química. A exposição de banana 'Maçã' a 50 ppb de 1-MCP, por 3 e 6 horas, não estendeu sua vida pós-colheita, tampouco alterou sua composição química. Embora a exposição de banana 'Maçã' a 50 ppb de 1-MCP, por 12 e 24 horas, tenha retardado o seu amadurecimento, promoveu alterações indesejáveis na casca do fruto. Logo, a aplicação de 50 ppb de 1-MCP, por 9 horas, antes da refrigeração, constitui-se numa alternativa viável para prolongar o período de comercialização da banana.The aim of this work was to evaluate 'Apple' banana different periods exposure effect to 50 ppb of 1-MCP (0, 3, 6, 9 and 24 hours on its postharvest life and quality. Mature-green fruits were stored for 30 days in chambers at 13ºC + 0,5 and relative humidity 95%, after exposure to 1-MCP. Then, the bananas were stored at 20ºC + 1 until peel complete yellowing. 'Apple' banana to 50 ppb of 1-MCP exposure during 9 hours delayed in seven days the fruit ripening, comparing to fruit control, after 30 days of cool storage (13ºC, without changing its appearance and chemical composition. The exposure of 'Apple' banana to 50 ppb of 1-MCP for 3 and 6 hours did not extend its postharvest life; neither changed its chemical composition. Although the exposure of

  19. RETARDAMENTO DA MATURAÇÃO DE MAÇÃS 'FUJI' PELO TRATAMENTO COM 1-MCP E MANEJO DA TEMPERATURA DELAYING 'FUJI' APPLE RIPENING BY 1-MCP TREATMENT AND MANAGEMENT OF STORAGE TEMPERATURE

    Directory of Open Access Journals (Sweden)

    LUIZ CARLOS ARGENTA

    2001-08-01

    Full Text Available Maçãs cv. Fuji foram tratadas com 42 mimol·m-3 de 1-metilciclopropeno (1-MCP por 24 h a 20°C, um dia após a colheita, e então armazenadas a 0; 10 ou 20ºC por 70 dias. Tratamento com 1-MCP efetivamente retardou a maturação de maçãs 'Fuji'. 1-MCP reduziu a taxa respiratória dos frutos mantidos a 10 e 20ºC e inibiu a produção de etileno dos frutos mantidos nas três temperaturas de armazenagem. Frutos tratados com 1-MCP e armazenados a 20ºC exibiram taxas respiratórias similares ou inferiores àquelas de frutos-controle armazenados a 10ºC. Quando armazenados a 10 ou 20ºC, frutos tratados com 1-MCP preservaram mais a firmeza da polpa e a acidez titulável e exibiram menor amarelecimento da epiderme que frutos-controle. Entretanto, não houve benefícios significativos do tratamento 1-MCP sobre a conservação da qualidade dos frutos armazenados a 0ºC no período de 70 dias após a colheita. Os resultados indicam que o tratamento com 1-MCP pode ser uma estratégia para o aumento da conservação de maçãs cv. Fuji durante o transporte e a distribuição sob 10 ou 20ºC. O prolongamento da armazenagem a 20ºC por período superior a 40 dias pode ser limitado pelo murchamento dos frutos e desenvolvimento de podridões.'Fuji' apples were treated with 42 mumol·m-3 of 1-methylcyclopropene (1-MCP for 24 h at 20°C then stored at 0, 10 or 20 ºC for 70 days. MCP treatment reduced respiration on fruit held at 10 and 20 ºC and inhibited ethylene production regardless of storage temperature. Treated fruits held at 20ºC presented respiration rate similar to those of untreated fruits held at 10ºC. For fruit held at 10 or 20ºC, MCP treatment inhibited softening, loss of acidity and color changes on fruit surface. However, there was no considerable benefit of 1-MCP treatment on maintenance of fruit quality during short-term (70 days and storage at 0ºC. Results indicated that 1-MCP is an effective mean to delay ripening and to retain

  20. The human MCP-2 gene (SCYA8): Cloning, sequence analysis, tissue expression, and assignment to the CC chemokine gene contig on chromosome 17q11.2

    Energy Technology Data Exchange (ETDEWEB)

    Van Coillie, E.; Fiten, P.; Van Damme, J.; Opdenakker, G. [Univ. of Leuven (Belgium)] [and others

    1997-03-01

    Monocyte chemotactic proteins (MCPs) form a subfamily of chemokines that recruit leukocytes to sites of inflammation and that may contribute to tumor-associated leukocyte infiltration and to the antiviral state against HIV infection. With the use of degenerate primers that were based on CC chemokine consensus sequences, the known MIP-1{alpha}/LD78{alpha}, MCP-1, and MCP-3 genes and the previously unidentified eotaxin and MCP-2 genes were isolated from a YAC contig from human chromosome 17q11.2. The amplified genomic MCP-2 fragment was used to isolate an MCP-2 cosmid from which the gene sequence was determined. The MCP-2 gene shares with the MCP-1 and MCP-3 genes a conserved intron-exon structure and a coding nucleotide sequence homology of 77%. By Northern blot analysis the 1.0-kb MCP-2 mRNA was predominantly detectable in the small intestine, peripheral blood, heart, placenta, lung, skeletal muscle, ovary, colon, spinal cord, pancreas, and thymus. Transcripts of 1.5 and 2.4 kb were found in the testis, the small intestine, and the colon. The isolation of the MCP-2 gene from the chemokine contig localized it on YAC clones of chromosome 17q11.2, which also contain the eotaxin, MCP-1, MCP-3, and NCC-1/MCP-4 genes. The combination of using degenerate primer PCR and YACs illustrates that novel genes can efficiently be isolated from gene cluster contigs with less redundancy and effort than the isolation of novel ESTs. 42 refs., 5 figs., 2 tabs.

  1. Modeling Photo-multiplier Gain and Regenerating Pulse Height Data for Application Development

    Science.gov (United States)

    Aspinall, Michael D.; Jones, Ashley R.

    2018-01-01

    Systems that adopt organic scintillation detector arrays often require a calibration process prior to the intended measurement campaign to correct for significant performance variances between detectors within the array. These differences exist because of low tolerances associated with photo-multiplier tube technology and environmental influences. Differences in detector response can be corrected for by adjusting the supplied photo-multiplier tube voltage to control its gain and the effect that this has on the pulse height spectra from a gamma-only calibration source with a defined photo-peak. Automated methods that analyze these spectra and adjust the photo-multiplier tube bias accordingly are emerging for hardware that integrate acquisition electronics and high voltage control. However, development of such algorithms require access to the hardware, multiple detectors and calibration source for prolonged periods, all with associated constraints and risks. In this work, we report on a software function and related models developed to rescale and regenerate pulse height data acquired from a single scintillation detector. Such a function could be used to generate significant and varied pulse height data that can be used to integration-test algorithms that are capable of automatically response matching multiple detectors using pulse height spectra analysis. Furthermore, a function of this sort removes the dependence on multiple detectors, digital analyzers and calibration source. Results show a good match between the real and regenerated pulse height data. The function has also been used successfully to develop auto-calibration algorithms.

  2. Low-order-mode harmonic multiplying gyrotron traveling-wave amplifier in W band

    International Nuclear Information System (INIS)

    Yeh, Y. S.; Chen, C. H.; Yang, S. J.; Lai, C. H.; Lin, T. Y.; Lo, Y. C.; Hong, J. W.; Hung, C. L.; Chang, T. H.

    2012-01-01

    Harmonic multiplying gyrotron traveling-wave amplifiers (gyro-TWAs) allow for magnetic field reduction and frequency multiplication. To avoid absolute instabilities, this work proposes a W-band harmonic multiplying gyro-TWA operating at low-order modes. By amplifying a fundamental harmonic TE 11 drive wave, the second harmonic component of the beam current initiates a TE 21 wave to be amplified. Absolute instabilities in the gyro-TWA are suppressed by shortening the interaction circuit and increasing wall losses. Simulation results reveal that compared with Ka-band gyro-TWTs, the lower wall losses effectively suppress absolute instabilities in the W-band gyro-TWA. However, a global reflective oscillation occurs as the wall losses decrease. Increasing the length or resistivity of the lossy section can reduce the feedback of the oscillation to stabilize the amplifier. The W-band harmonic multiplying gyro-TWA is predicted to yield a peak output power of 111 kW at 98 GHz with an efficiency of 25%, a saturated gain of 26 dB, and a bandwidth of 1.6 GHz for a 60 kV, 7.5 A electron beam with an axial velocity spread of 8%.

  3. TRPV1 and the MCP-1/CCR2 Axis Modulate Post-UTI Chronic Pain.

    Science.gov (United States)

    Rosen, John M; Yaggie, Ryan E; Woida, Patrick J; Miller, Richard J; Schaeffer, Anthony J; Klumpp, David J

    2018-05-08

    The etiology of chronic pelvic pain syndromes remains unknown. In a murine urinary tract infection (UTI) model, lipopolysaccharide of uropathogenic E. coli and its receptor TLR4 are required for post-UTI chronic pain development. However, downstream mechanisms of post-UTI chronic pelvic pain remain unclear. Because the TRPV1 and MCP-1/CCR2 pathways are implicated in chronic neuropathic pain, we explored their role in post-UTI chronic pain. Mice were infected with the E. coli strain SΦ874, known to produce chronic allodynia, and treated with the TRPV1 antagonist capsazepine. Mice treated with capsazepine at the time of SΦ874 infection failed to develop chronic allodynia, whereas capsazepine treatment of mice at two weeks following SΦ874 infection did not reduce chronic allodynia. TRPV1-deficient mice did not develop chronic allodynia either. Similar results were found using novelty-suppressed feeding (NSF) to assess depressive behavior associated with neuropathic pain. Imaging of reporter mice also revealed induction of MCP-1 and CCR2 expression in sacral dorsal root ganglia following SΦ874 infection. Treatment with a CCR2 receptor antagonist at two weeks post-infection reduced chronic allodynia. Taken together, these results suggest that TRPV1 has a role in the establishment of post-UTI chronic pain, and CCR2 has a role in maintenance of post-UTI chronic pain.

  4. Combined use of serum MCP-1/IL-10 ratio and uterine artery Doppler index significantly improves the prediction of preeclampsia.

    Science.gov (United States)

    Cui, Shihong; Gao, Yanan; Zhang, Linlin; Wang, Yuan; Zhang, Lindong; Liu, Pingping; Liu, Ling; Chen, Juan

    2017-10-01

    Monocyte chemotactic protein-1 (MCP-1, or CCL2) is a member of the chemokine subfamily involved in recruitment of monocytes in inflammatory tissues. IL-10 is a key regulator for maintaining the balance of anti-inflammatory and pro-inflammatory milieu at the feto-maternal interface. Doppler examination has been routinely performed for the monitoring and management of preeclampsia patients. This study evaluates the efficiency of these factors alone, or in combination, for the predication of preeclampsia. The serum levels of MCP-1 and IL-10 in 78 preeclampsia patients and 143 age-matched normal controls were measured. The Doppler ultrasonography was performed and Artery Pulsatility Index (PI) and Resistance Index (RI) were calculated for the same subjects. It was found that while the second-trimester serum MCP-1, IL-10, MCP-1/IL-10 ratio, PI, and RI showed some power in predicting preeclampsia, the combination of MCP-1/IL-10 and PI and RI accomplishes the highest efficiency, achieving an AUC of 0.973 (95% CI, 0.000-1.000, Ppreeclampsia. Future studies using a larger sample can be conducted to construct an algorithm capable of quantitative assessment on the risk of preeclampsia. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Tables of compound-discount interest rate multipliers for evaluating forestry investments.

    Science.gov (United States)

    Allen L. Lundgren

    1971-01-01

    Tables, prepared by computer, are presented for 10 selected compound-discount interest rate multipliers commonly used in financial analyses of forestry investments. Two set of tables are given for each of the 10 multipliers. The first set gives multipliers for each year from 1 to 40 years; the second set gives multipliers at 5-year intervals from 5 to 160 years....

  6. Aplicação de 1-MCP em caqui 'quioto' armazenado sob refrigeração e atmosfera controlada Effect of 1-MCP applied at different times during cold and Ca storage

    Directory of Open Access Journals (Sweden)

    Auri Brackmann

    2003-04-01

    Full Text Available O objetivo deste trabalho foi de avaliar o efeito do 1-MCP aplicado em diferentes épocas durante o armazenamento refrigerado (AR e em atmosfera controlada (AC sobre a qualidade do caqui cv. Quioto. O delineamento experimental utilizado foi o inteiramente casualizado, com quatro repetições de 30 frutos, e os tratamentos foram os seguintes: armazenamento refrigerado (AR; armazenamento refrigerado(AR + 1-MCP (1000ppb no início do armazenamento; armazenamento refrigerado(AR +1-MCP (1000ppb no final do armazenamento; armazenamento em atmosfera controlada (AC com 1kPa de O2 e AC 5kPa de CO2 e AC com 1kPa de O2 e 5kPa de CO2 + 1-MCP no fim do armazenamento, após 2 meses de armazenamento a -0,5ºC mais 5 dias de exposição dos frutos a 10ºC e 3 dias a 20ºC. No armazenamento refrigerado, o 1-MCP, aplicado tanto no início do armazenamento como no final, proporcionou maior firmeza de polpa. Para os parâmetros: sólidos solúveis totais, podridão e escurecimento da película, não houve diferença estatística entre os tratamentos. Conclui-se que a aplicação de 1-MCP, tanto no início como no final do armazenamento mantém elevada a firmeza de polpa.The objective of this work was to evaluate the effect of 1-MCP applied at different period during the cold storage (CS and in controlled atmosphere (CA on the quality of 'Quioto'. Persimmon. The experimental design was completely randomized with four replications of 30 fruits and the tested treatments were: cold storage (CS, cold storage + 1-MCP (1000ppb in the beginning of the storage, cold storage + 1-MCP (1000ppb in the end of the storage period; storage in controlled atmosphere (CA with 1kPa of O2 and 5kPa of CO2 and 1kPa of O2 and 5kPa of CO2 + 1-MCP in the end of the storage, after 2 months of storage at -0.5ºC, plus 5 days at 10ºC and 3 days at 20ºC. In the cooled storage, the 1-MCP, applied as in the beginning of the storage as in the end of the storage, provided greater pulp firmness

  7. Pós colheita de bananas-maçã submetidas ao 1-MCP e armazenadas á temperatura ambiente Postharvest of 'apple' banana submetted to 1-MCP and storage in room temperature

    Directory of Open Access Journals (Sweden)

    Ana Carla Marque Pinheiro

    2006-04-01

    Full Text Available Bananas da cultivar Maçã foram adquiridas no estádio dois de coloração da casca (verde maturos e submetidas à ação de 1-MCP. O 1-MCP foi aplicado por 12 horas nas seguintes concentrações: 0 (controle, 50, 100, 150, 200 hL.L-1. Após aplicação, os frutos foram armazenados à temperatura ambiente (temperatura média 20ºC ± 1 e umidade relativa 80% ± 5 e avaliados à medida que atingiam os graus 3, 5 e 7 de coloração da casca. O tratamento com 1-MCP atrasou o início do amadurecimento de bananas-maçã armazenadas sob temperatura ambiente, baseado nas primeiras mudanças de coloração da casca. A aplicação de 1-MCP em bananas-maçã, ditou maiores valores de perda de massa e relação polpa/casca (nos graus 5 e 7 de coloração da casca. O 1-MCP, nas doses 100, 150 e 200 hL.L-1 de 1-MCP promoveu desverdecimento desuniforme e tonalidade avermelhada na casca. O tratamento 50 hL.L-1 de 1-MCP é o mais adequado, por promover a extensão da vida pós-colheita de bananas-maçã da cultivar armazenadas sob temperatura ambiente sem afetar a coloração da casca dos frutos, apresentando qualidade, baseando-se na cor da casca, firmeza, acidez titulável, pH e sólidos solúveis, semelhante ao controle.Mature green 'Apple' bananas were submitted to five concentrations of 1-MCP (0, 50, 100, 150 and 200 hL.L-1 for 12 hours. After treatment, the fruits were stored at room temperature (20ºC ± 1 and 80% ± 5 RH and analyzed at 3,5 and 7 color degree of peel. The treatment with 1-MCP delayed the start of the ripening based in the first changes of peel color. The treatment of 'Apple' bananas with 1-MCP promoted higher values of mass loss and pulp/peel ratio (5 and 7 degrees of color peel. The fruits treated with 100, 150 and 200 nL.L-1 of 1-MCP showed heterogeneous degreening and development of red color on the peel. 1-MCP at 50 nL.L-1 was the most appropriated treatment for promoting the extension of postharvest life of 'Apple' bananas stored

  8. On centralized power pool auction: a novel multipliers stabilization procedure

    International Nuclear Information System (INIS)

    Jimenez-Redondo, Noemi

    2005-01-01

    This paper addresses the Short-Term Hydro-Thermal Coordination (STHTC) problem. It is a large-scale, combinatorial and nonlinear optimization problem. It is usually solved using a Lagrangian Relaxation (LR) approach. LR procedure is based on the solution of the dual problem of the original one. The dual problem variables are the Lagrange multipliers. These multipliers have an economic meaning: electric energy hourly prices. This paper focuses on an efficient solution of the dual problem of the STHTC problem. A novel multiplier stabilization technique, which significantly improves the quality of the solution, is presented. The provided method could be the optimization tool used by the Independent System Operator of a centralized Power Pool. The solution procedure diminishes the conflict of interest in determining energy prices. A realistic large-scale case study illustrates the behavior of the presented approach. (Author)

  9. New design of an RSFQ parallel multiply-accumulate unit

    International Nuclear Information System (INIS)

    Kataeva, Irina; Engseth, Henrik; Kidiyarova-Shevchenko, Anna

    2006-01-01

    The multiply-accumulate unit (MAC) is a central component of a successive interference canceller, an advanced receiver for W-CDMA base stations. A 4 x 4 two's complement fixed point RSFQ MAC with rounding to 5 bits has been simulated using VHDL, and maximum performance is equal to 24 GMACS (giga-multiply-accumulates per second). The clock distribution network has been re-designed from a linear ripple to a binary tree network in order to eliminate the data dependence of the clock propagation speed and reduce the number of Josephson junctions in clock lines. The 4 x 4 bit MAC has been designed for the HYPRES 4.5 kA cm -2 process and its components have been experimentally tested at low frequency: the 5-bit combiner, using an exhaustive test pattern, had margins on DC bias voltage of ± 18%, and the 4 x 4 parallel multiplier had margins equal to ± 2%

  10. Multiplier Accounting of Indian Mining Industry: The Application

    Science.gov (United States)

    Hussain, Azhar; Karmakar, Netai Chandra

    2017-10-01

    In the previous paper (Hussain and Karmakar in Inst Eng India Ser, 2014. doi: 10.1007/s40033-014-0058-0), the concepts of input-output transaction matrix and multiplier were explained in detail. Input-output multipliers are indicators used for predicting the total impact on an economy due to changes in its industrial demand and output which is calculated using transaction matrix. The aim of this paper is to present an application of the concepts with respect to the mining industry, showing progress in different sectors of mining with time and explaining different outcomes from the results obtained. The analysis shows that a few mineral industries saw a significant growth in their multiplier values over the years.

  11. Dark energy from modified gravity with Lagrange multipliers

    International Nuclear Information System (INIS)

    Capozziello, Salvatore; Matsumoto, Jiro; Nojiri, Shin'ichi; Odintsov, Sergei D.

    2010-01-01

    We study scalar-tensor theory, k-essence and modified gravity with Lagrange multiplier constraint which role is to reduce the number of degrees of freedom. Dark Energy cosmology of different types (ΛCDM, unified inflation with DE, smooth non-phantom/phantom transition epoch) is reconstructed in such models. It is demonstrated that presence of Lagrange multiplier simplifies the reconstruction scenario. It is shown that mathematical equivalence between scalar theory and F(R) gravity is broken due to presence of constraint. The cosmological evolution is defined by the second F 2 (R) function dictated by the constraint. The convenient F(R) gravity sector is relevant for local tests. This opens the possibility to make originally non-realistic theory to be viable by adding the corresponding constraint. A general discussion on the role of Lagrange multipliers to make higher-derivative gravity canonical is developed.

  12. Study on neutron irradiation behavior of beryllium as neutron multiplier

    Energy Technology Data Exchange (ETDEWEB)

    Ishitsuka, Etsuo [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

    1998-03-01

    More than 300 tons beryllium is expected to be used as a neutron multiplier in ITER, and study on the neutron irradiation behavior of beryllium as the neutron multiplier with Japan Materials Testing Reactor (JMTR) were performed to get the engineering data for fusion blanket design. This study started as the study on the tritium behavior in beryllium neutron reflector in order to make clear the generation mechanism on tritium of JMTR primary coolant since 1985. These experiences were handed over to beryllium studies for fusion study, and overall studies such as production technology of beryllium pebbles, irradiation behavior evaluation and reprocessing technology have been started since 1990. In this presentation, study on the neutron irradiation behavior of beryllium as the neutron multiplier with JMTR was reviewed from the point of tritium release, thermal properties, mechanical properties and reprocessing technology. (author)

  13. Splay states in globally coupled Josephson arrays: Analytical prediction of Floquet multipliers

    International Nuclear Information System (INIS)

    Strogatz, S.H.; Mirollo, R.E.

    1993-01-01

    In recent numerical experiments on series arrays of overdamped Josephson junctions, Nichols and Wiesenfeld [Phys. Rev. A 45, 8430 (1992)] discovered that the periodic states known as splay states are neutrally stable in all but four directions in phase space. We present a theory that accounts for this enormous degree of neutral stability. The theory also predicts the four non-neutral Floquet multipliers to within 0.1% of their numerically computed values. The analytical approach used here may be appli- cable to other globally coupled systems of oscillators, such as multimode lasers, electronic oscillator circuits, and solid-state laser arrays

  14. Time efficient signed Vedic multiplier using redundant binary representation

    Directory of Open Access Journals (Sweden)

    Ranjan Kumar Barik

    2017-03-01

    Full Text Available This study presents a high-speed signed Vedic multiplier (SVM architecture using redundant binary (RB representation in Urdhva Tiryagbhyam (UT sutra. This is the first ever effort towards extension of Vedic algorithms to the signed numbers. The proposed multiplier architecture solves the carry propagation issue in UT sutra, as carry free addition is possible in RB representation. The proposed design is coded in VHDL and synthesised in Xilinx ISE 14.4 of various FPGA devices. The proposed SVM architecture has better speed performances as compared with various state-of-the-art conventional as well as Vedic architectures.

  15. Radial multipliers on amalgamated free products of II-factors

    DEFF Research Database (Denmark)

    Möller, Sören

    2014-01-01

    Let ℳi be a family of II1-factors, containing a common II1-subfactor 풩, such that [ℳi : 풩] ∈ ℕ0 for all i. Furthermore, let ϕ: ℕ0 → ℂ. We show that if a Hankel matrix related to ϕ is trace-class, then there exists a unique completely bounded map Mϕ on the amalgamated free product of the ℳi...... with amalgamation over 풩, which acts as a radial multiplier. Hereby, we extend a result of Haagerup and the author for radial multipliers on reduced free products of unital C*- and von Neumann algebras....

  16. Monocytes infiltrate the pancreas via the MCP-1/CCR2 pathway and differentiate into stellate cells.

    Directory of Open Access Journals (Sweden)

    Kazuko Ino

    Full Text Available Recent studies have shown that monocytes possess pluripotent plasticity. We previously reported that monocytes could differentiate into hepatic stellate cells. Although stellate cells are also present in the pancreas, their origin remains unclear. An accumulation of enhanced green fluorescent protein (EGFP(+CD45(- cells was observed in the pancreases and livers of chimeric mice, which were transplanted with a single hematopoietic stem cell isolated from EGFP-transgenic mice and treated with carbon tetrachloride (CCl4. Because the vast majority of EGFP(+CD45(- cells in the pancreas expressed stellate cell-associated antigens such as vimentin, desmin, glial fibrillary acidic protein, procollagen-I, and α-smooth muscle actin, they were characterized as pancreatic stellate cells (PaSCs. EGFP(+ PaSCs were also observed in CCl4-treated mice adoptively transferred with monocytes but not with other cell lineages isolated from EGFP-transgenic mice. The expression of monocyte chemoattractant protein-1 (MCP-1 and angiotensin II (Ang II increased in the pancreas of CCl4-treated mice and their respective receptors, C-C chemokine receptor 2 (CCR2 and Ang II type 1 receptor (AT1R, were expressed on Ly6C(high monocytes isolated from EGFP-transgenic mice. We examined the effect of an AT1R antagonist, irbesartan, which is also a CCR2 antagonist, on the migration of monocytes into the pancreas. Monocytes migrated toward MCP-1 but not Ang II in vitro. Irbesartan inhibited not only their in vitro chemotaxis but also in vivo migration of adoptively transferred monocytes from peripheral blood into the pancreas. Irbesartan treatment significantly reduced the numbers of EGFP(+F4/80(+CCR2(+ monocytic cells and EGFP(+ PaSCs in the pancreas of CCl4-treated chimeric mice receiving EGFP(+ bone marrow cells. A specific CCR2 antagonist RS504393 inhibited the occurrence of EGFP(+ PaSCs in injured mice. We propose that CCR2(+ monocytes migrate into the pancreas possibly via the

  17. Insulin resistance is associated with MCP1-mediated macrophage accumulation in skeletal muscle in mice and humans.

    Directory of Open Access Journals (Sweden)

    David Patsouris

    Full Text Available Inflammation is now recognized as a major factor contributing to type 2 diabetes (T2D. However, while the mechanisms and consequences associated with white adipose tissue inflammation are well described, very little is known concerning the situation in skeletal muscle. The aim of this study was to investigate, in vitro and in vivo, how skeletal muscle inflammation develops and how in turn it modulates local and systemic insulin sensitivity in different mice models of T2D and in humans, focusing on the role of the chemokine MCP1. Here, we found that skeletal muscle inflammation and macrophage markers are increased and associated with insulin resistance in mice models and humans. In addition, we demonstrated that intra-muscular TNFα expression is exclusively restricted to the population of intramuscular leukocytes and that the chemokine MCP1 was associated with skeletal muscle inflammatory markers in these models. Furthermore, we demonstrated that exposure of C2C12 myotubes to palmitate elevated the production of the chemokine MCP1 and that the muscle-specific overexpression of MCP1 in transgenic mice induced the local recruitment of macrophages and altered local insulin sensitivity. Overall our study demonstrates that skeletal muscle inflammation is clearly increased in the context of T2D in each one of the models we investigated, which is likely consecutive to the lipotoxic environment generated by peripheral insulin resistance, further increasing MCP1 expression in muscle. Consequently, our results suggest that MCP1-mediated skeletal muscle macrophages recruitment plays a role in the etiology of T2D.

  18. New stable multiply charged negative atomic ions in linearly polarized superintense laser fields

    International Nuclear Information System (INIS)

    Wei Qi; Kais, Sabre; Moiseyev, Nimrod

    2006-01-01

    Singly charged negative atomic ions exist in the gas phase and are of fundamental importance in atomic and molecular physics. However, theoretical calculations and experimental results clearly exclude the existence of any stable doubly-negatively-charged atomic ion in the gas phase, only one electron can be added to a free atom in the gas phase. In this report, using the high-frequency Floquet theory, we predict that in a linear superintense laser field one can stabilize multiply charged negative atomic ions in the gas phase. We present self-consistent field calculations for the linear superintense laser fields needed to bind extra one and two electrons to form He - , He 2- , and Li 2- , with detachment energies dependent on the laser intensity and maximal values of 1.2, 0.12, and 0.13 eV, respectively. The fields and frequencies needed for binding extra electrons are within experimental reach. This method of stabilization is general and can be used to predict stability of larger multiply charged negative atomic ions

  19. Plasma cytokines eotaxin, MIP-1α, MCP-4, and vascular endothelial growth factor in acute lower respiratory tract infection

    DEFF Research Database (Denmark)

    Relster, Mette Marie; Holm, Anette; Pedersen, Court

    2017-01-01

    ), monocyte chemoattractant protein 4 (MCP-4), and vascular endothelial growth factor (VEGF) in 40 patients hospitalized with acute lower respiratory tract infections (LRTI). The cytokines contribute to the pathogenesis of several inflammatory respiratory diseases, indicating a potential as markers for LRTI....... Patients were stratified according to etiology and severity of LRTI, based on baseline C-reactive protein and CURB-65 scores. Using a multiplex immunoassay of plasma, levels of eotaxin and MCP-4 were shown to increase from baseline until day 6 after admission to hospital. The four cytokines were unable...

  20. Evaluation of BICRON NE MCP DXT-RAD passive extremity dosemeter

    CERN Document Server

    Yuen, P S; Frketich, G; Rotunda, J

    1999-01-01

    Passive extremity dosemeters currently used in dosimetry communities worldwide have shortcomings. In general, an extremity dosemeter has too thick a detector element, and the dosemeter response is highly energy dependent for beta rays with energies ranging from 200 keV to 2 MeV. It often does not have dosemeter identification, causing problems in the chain of custody. It is often read manually, rendering reading/packing operations very labour intensive. As a result of collaboration between AECL and BICRON NE, a new extremity dosemeter, incorporating a highly sensitive LiF:Mg,Cu,P TLD and tentatively code named MCP DXT-RAD, was developed. It has been evaluated for radiological performance against an ISO draft standard for extremity dosemeters in twelve categories: homogeneity, detection threshold, beta ray energy response, beta angular response, photon energy response, photon angular response, reproducibility, stability under various climatic conditions, linearity, residue, self irradiation, and effect of ligh...

  1. Intermittent pneumatic leg compressions acutely upregulate VEGF and MCP-1 expression in skeletal muscle.

    Science.gov (United States)

    Roseguini, Bruno T; Mehmet Soylu, S; Whyte, Jeffrey J; Yang, H T; Newcomer, Sean; Laughlin, M Harold

    2010-06-01

    Application of intermittent pneumatic compressions (IPC) is an extensively used therapeutic strategy in vascular medicine, but the mechanisms by which this method works are unclear. We tested the hypothesis that acute application (150 min) of cyclic leg compressions in a rat model signals upregulation of angiogenic factors in skeletal muscle. To explore the impact of different pressures and frequency of compressions, we divided rats into four groups as follows: 120 mmHg (2 s inflation/2 s deflation), 200 mmHg (2 s/2 s), 120 mmHg (4 s/16 s), and control (no intervention). Blood flow and leg oxygenation (study 1) and the mRNA expression of angiogenic mediators in the rat tibialis anterior muscle (study 2) were assessed after a single session of IPC. In all three groups exposed to the intervention, a modest hyperemia (approximately 37% above baseline) between compressions and a slight, nonsignificant increase in leg oxygen consumption (approximately 30%) were observed during IPC. Compared with values in the control group, vascular endothelial growth factor (VEGF) and monocyte chemotactic protein-1 (MCP-1) mRNA increased significantly (P < 0.05) only in rats exposed to the higher frequency of compressions (2 s on/2 s off). Endothelial nitric oxide synthase, matrix metalloproteinase-2, and hypoxia-inducible factor-1alpha mRNA did not change significantly following the intervention. These findings show that IPC application augments the mRNA content of key angiogenic factors in skeletal muscle. Importantly, the magnitude of changes in mRNA expression appeared to be modulated by the frequency of compressions such that a higher frequency (15 cycles/min) evoked more robust changes in VEGF and MCP-1 compared with a lower frequency (3 cycles/min).

  2. ANALYSIS OF THE INVESTMENT ARBITRAGE STRATEGY USING FINANCIAL MULTIPLIERS

    Directory of Open Access Journals (Sweden)

    Dmitry S. Pashkov

    2013-01-01

    Full Text Available This article describes an algorithm for stock pairs trading using financial multipliers of underlying companies. This algorithm has been tested on historical data and compared with classical Bollinger bands strategy. The results of tests were presented for two financial sectors of US stock market.

  3. Garbage-free reversible constant multipliers for arbitrary integers

    DEFF Research Database (Denmark)

    Mogensen, Torben Ægidius

    2013-01-01

    We present a method for constructing reversible circuitry for multiplying integers by arbitrary integer constants. The method is based on Mealy machines and gives circuits whose size are (in the worst case) linear in the size of the constant. This makes the method unsuitable for large constants...

  4. Smooth bifurcation for variational inequalities based on Lagrange multipliers

    Czech Academy of Sciences Publication Activity Database

    Eisner, Jan; Kučera, Milan; Recke, L.

    2006-01-01

    Roč. 19, č. 9 (2006), s. 981-1000 ISSN 0893-4983 R&D Projects: GA AV ČR(CZ) IAA100190506 Institutional research plan: CEZ:AV0Z10190503 Keywords : abstract variational inequality * bifurcation * Lagrange multipliers Subject RIV: BA - General Mathematics

  5. Detection of differential item functioning using Lagrange multiplier tests

    NARCIS (Netherlands)

    Glas, Cornelis A.W.

    1998-01-01

    Abstract: In the present paper it is shown that differential item functioning can be evaluated using the Lagrange multiplier test or Rao’s efficient score test. The test is presented in the framework of a number of IRT models such as the Rasch model, the OPLM, the 2-parameter logistic model, the

  6. Detection of differential item functioning using Lagrange multiplier tests

    NARCIS (Netherlands)

    Glas, Cornelis A.W.

    1996-01-01

    In this paper it is shown that differential item functioning can be evaluated using the Lagrange multiplier test or C. R. Rao's efficient score test. The test is presented in the framework of a number of item response theory (IRT) models such as the Rasch model, the one-parameter logistic model, the

  7. Lagrange-multiplier tests for weak exogeneity: a synthesis.

    NARCIS (Netherlands)

    Boswijk, H.P.; Urbain, J.P.

    1997-01-01

    This paper unifies two seemingly separate approaches to test weak exogeneity in dynamic regression models with Lagrange-multiplier statistics. The first class of tests focuses on the orthogonality between innovations and conditioning variables, and thus is related to the Durbin-Wu-Hausman

  8. Fiscal multipliers over the growth cycle : evidence from Malaysia

    OpenAIRE

    Rafiq, Sohrab; Zeufack, Albert

    2012-01-01

    This paper explores the stabilisation properties of fiscal policy in Malaysia using a model incorporating nonlinearities into the dynamic relationship between fiscal policy and real economic activity over the growth cycle. The paper also investigates how output multipliers for government purchases may alter for different components of government spending. The authors find that fiscal polic...

  9. A database analysis of information on multiply charged ions

    International Nuclear Information System (INIS)

    Delcroix, J.L.

    1989-01-01

    A statistical analysis of data related to multiply charged ions, is performed in GAPHYOR data base: over-all statistics by ionization degree from q=1 to q=99, 'historical' development from 1975 to 1987, distribution (for q≥ 5) over physical processes (energy levels, charge exchange,...) and chemical elements

  10. Multiple images of our galaxy in closed, multiply connected cosmologies

    International Nuclear Information System (INIS)

    Fagundes, H.V.

    1985-01-01

    Friedmanian cosmology with multiply connected spatial sections allows multiple images of cosmic sources, in particular of the galaxy itself. This is illustrated with a specific example of a closed hyperbolic model and a brief mention of a spherical model. Such images may eventually become observable (or recognized as such), thus providing a new test of relativistic cosmology. (Author) [pt

  11. A CMOS four-quadrant analog current multiplier

    NARCIS (Netherlands)

    Wiegerink, Remco J.

    1991-01-01

    A CMOS four-quadrant analog current multiplier is described. The circuit is based on the square-law characteristic of an MOS transistor and is insensitive to temperature and process variations. The circuit is insensitive to the body effect so it is not necessary to place transistors in individual

  12. The evolution of unconditional strategies via the 'multiplier effect'.

    Science.gov (United States)

    McNamara, John M; Dall, Sasha R X

    2011-03-01

    Ostensibly, it makes sense in a changeable world to condition behaviour and development on information when it is available. Nevertheless, unconditional behavioural and life history strategies are widespread. Here, we show how intergenerational effects can limit the evolutionary value of responding to reliable environmental cues, and thus favour the evolutionary persistence of otherwise paradoxical unconditional strategies. While cue-ignoring genotypes do poorly in the wrong environments, in the right environment they will leave many copies of themselves, which will themselves leave many copies, and so on, leading genotypes to accumulate in habitats in which they do well. We call this 'The Multiplier Effect'. We explore the consequences of the multiplier effect by focussing on the ecologically important phenomenon of natal philopatry. We model the environment as a large number of temporally varying breeding sites connected by natal dispersal between sites. Our aim is to identify which aspects of an environment promote the multiplier effect. We show, if sites remain connected through some background level of 'accidental' dispersal, unconditional natal philopatry can evolve even when there is density dependence (with its accompanying kin competition effects), and cues that are only mildly erroneous. Thus, the multiplier effect may underpin the evolution and maintenance of unconditional strategies such as natal philopatry in many biological systems. © 2011 Blackwell Publishing Ltd/CNRS.

  13. A cascaded three-phase symmetrical multistage voltage multiplier

    International Nuclear Information System (INIS)

    Iqbal, Shahid; Singh, G K; Besar, R; Muhammad, G

    2006-01-01

    A cascaded three-phase symmetrical multistage Cockcroft-Walton voltage multiplier (CW-VM) is proposed in this report. It consists of three single-phase symmetrical voltage multipliers, which are connected in series at their smoothing columns like string of batteries and are driven by three-phase ac power source. The smoothing column of each voltage multiplier is charged twice every cycle independently by respective oscillating columns and discharged in series through load. The charging discharging process completes six times a cycle and therefore the output voltage ripple's frequency is of sixth order of the drive signal frequency. Thus the proposed approach eliminates the first five harmonic components of load generated voltage ripples and sixth harmonic is the major ripple component. The proposed cascaded three-phase symmetrical voltage multiplier has less than half the voltage ripple, and three times larger output voltage and output power than the conventional single-phase symmetrical CW-VM. Experimental and simulation results of the laboratory prototype are given to show the feasibility of proposed cascaded three-phase symmetrical CW-VM

  14. Robust formation control of marine surface craft using Lagrange multipliers

    DEFF Research Database (Denmark)

    Ihle, Ivar-Andre F.; Jouffroy, Jerome; Fossen, Thor I.

    2006-01-01

    This paper presents a formation modelling scheme based on a set of inter-body constraint functions and Lagrangian multipliers. Formation control for a °eet of marine craft is achieved by stabilizing the auxiliary constraints such that the desired formation con¯guration appears. In the proposed fr...

  15. Familiar Sports and Activities Adapted for Multiply Impaired Persons.

    Science.gov (United States)

    Schilling, Mary Lou, Ed.

    1984-01-01

    Means of adapting some familiar and popular physical activities for multiply impaired persons are described. Games reviewed are dice baseball, one base baseball, in-house bowling, wheelchair bowling, ramp bowling, swing-ball bowling, table tennis, shuffleboard, beanbag bingo and tic-tac-toe, balloon basketball, circle football, and wheelchair…

  16. Changes in quality and biochemical parameters in 'Idared' apples during prolonged shelf life and 1-MCP treatment.

    Science.gov (United States)

    Bizjak, Jan; Slatnar, Ana; Stampar, Franci; Veberic, Robert

    2012-12-01

    In this study, changes in quality and various biochemical parameters of 'Idared' apples during prolonged shelf life period after ultra-low oxygen (ULO) storage were investigated. Additionally, the impact of the postharvest application of 1-methylcyclopropene (1-MCP) on different parameters was evaluated. After the harvest, apples were stored in the ULO storage for 6 months and then exposed to room temperature. Fruit firmness, peel color, and changes in sugars, organic acids and phenolics were monitored during the 3 weeks of shelf life. Malic acid, sugars and firmness decreased at room temperature. However, the color of the apples remained unchanged. The level of citric and ascorbic acid remained constant. Levels of phenolics in the peel increased significantly, whereas remained constant in the pulp of apples. 1-MCP treatment resulted in higher amounts of fructose and glucose, malic acid and greater firmness of apples. However, 1-MCP did not influence the phenolic content, ascorbic acid or color. The results obtained indicate that the content of different health-promoting compounds of apples does not change dramatically at room temperature. At the same time these results suggest that 1-MCP could be useful for maintaining certain quality and biochemical parameters and might extend the shelf life of apples.

  17. The resistive plate WELL detector as a single stage thick gaseous multiplier detector

    Energy Technology Data Exchange (ETDEWEB)

    Bressler, Shikma; Breskin, Amos; Moleri, Luca; Kumar, Ashwini; Pitt, Michael [Department of Particle Physics and Astrophysics, Weizmann Institute of Science (WIS) (Israel); Kudella, Simon [Institut fuer Experimentelle Kernphysik (IEKP), KIT (Germany)

    2015-07-01

    Gaseous Electron Multiplier (GEM) detector use high electric fields inside the h ole of a foil to achieve a high charge multiplication. As a thicker version of G EMs based on printed circuit board (PCB) structures, Thick Gaseous Electron Multiplier (THGEM) detectors combine the high gain of a GEM foil with the robustness, stability and low production costs of a PCB and allow a large quantity of applications that require the coverage of a large area at low cost and moderate spatial resolution. One application the Weizmann Institute of Science (WIS) develops as a member of the RD51 framework is the Resistive Plate WELL (RPWELL) detector. This single stage detector allows a very stable, discharge free operation at high gain (10{sup 5}). The single stage operation allows a low total height and make s the RPWELL a candidate for the Digital Hadronic Calorimeter (DHCAL) of the International Large Detector (ILD) at the International Linear Collider (ILC). The talk gives an insight into the way the RPWELL works and shows results from the last test beam.

  18. The association between MCP-1, VEGF polymorphisms and their serum levels in patients with diabetic foot ulcer.

    Science.gov (United States)

    Li, Xiaolei

    2018-06-01

    The purpose of the present study was to investigate distribution of monocyte chemoattractant protein-1 (MCP-1) -2518A/G and vascular endothelial growth factor (VEGF) -634G/C polymorphisms in type 2 diabetes melitus patients (T2DM) presenting diabetic foot ulcer (DFU). Additionally, we evaluated the effects of these 2 polymorphisms on serum levels of MCP-1 and VEGF in the study population.Patients diagnosed with T2DM without or with DFU were recruited in the study. The distribution of MCP-1 -2518A/G and VEGF -634G/C polymorphisms was investigated by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Enzyme-linked immunosorbent assay (ELISA) was applied to detect the protein levels of MCP-1 and VEGF. The comparisons of protein levels in DFU patients were performed by student t test according to their genotypes.The frequencies of GG genotype and G allele of MCP-1 -2518A/G was increased in DFU patients, compared with T2DM patients (odds ratio [OR] = 2.60, 95% confidence interval [CI] = 1.23-5.50, P = .011 and OR = 1.72, 95% CI = 1.18-2.50, P = .005, respectively). Moreover, the increased frequency of GG was significantly associated with up-regulated MCP-1 level in DFU patients (P < .001). Analysis for VEGF -634G/C polymorphisms indicated that the prevalence of CC genotype and C allele of the polymorphisms was decreased in DFU patients, compared with T2DM patients (OR = 0.36, 95% CI = 0.17-0.77, P = .008 and OR = 0.63, 95% CI = 0.43-0.91, P = .015, respectively). DFU patients carrying CC genotype had a higher level of VEGF than those with other genotypes (P = .007).MCP-1 -2518A/G and VEGF -634G/C polymorphisms may involve in occurrence and progress of DFU through regulating transcription activity of the genes.

  19. Controlled atmosphere pO2 alters ripening dynamics of 1-MCP treated ‘d’Anjou’ pear (Pyrus communis L.) fruit

    Science.gov (United States)

    Ripening and development of physiological disorders and decay were assessed in ‘d’Anjou’ pear fruit following 1-methylcyclopropene (1-MCP) treatment and cold storage in air or controlled atmosphere (CA). Fruit were exposed after harvest to 0 or 12.6 µmol•L-1 1-MCP and then stored at 0.5 oC in air o...

  20. Combination of IL-6, IL-10, and MCP-1 with traditional serum tumor markers in lung cancer diagnosis and prognosis.

    Science.gov (United States)

    Pan, Y W; Zhou, Z G; Wang, M; Dong, J Q; Du, K P; Li, S; Liu, Y L; Lv, P J; Gao, J B

    2016-11-03

    Early detection and treatment is critically important for lung cancer patients. Inflammatory mediators such as IL-6, IL-10, and MCP-1 participate in lung cancer regulation. CEA, CA125, and ProGRP are commonly used serum tumor markers for lung cancer. In this study, we assessed the sensitivity and specificity of CEA, CA125, and ProGRP when used in combination with IL-6, IL-10, and MCP in lung cancer diagnosis. Serum from three different groups (healthy controls, individuals with high risk for lung cancer, and lung cancer patients) was collected. Electrochemiluminescence was used to detect expressions of CEA, CA125, and ProGRP; ELISA was used to examine serum levels of IL-6, IL-10, and MCP-1. Specificity and sensitivity of single as well as combination markers in lung cancer diagnosis were determined. Results indicated that CEA, CA125, ProGRP, and MCP-1 were significantly up-regulated in lung cancer patients as compared to those in controls and high risk individuals. Higher IL-6 and IL-10 levels were observed in both lung cancer patients and high-risk individuals as compared to those in controls. Highest sensitivity (95.2%) in cancer diagnosis was achieved when all six markers were used. This was followed by a combination of IL-6, IL-10, CEA, CA125, and ProGRP (92.6%). The most sensitive (88.6%). Four-marker combination was composed of IL-6, CEA, CA125, and ProGRP. As the combined usage of CEA, CA125, ProGRP, IL-6, IL-10, and MCP-1 significantly improved sensitivity of lung cancer detection; this biomarker arrangement may be beneficial for early diagnosis, treatment, and prognosis of lung cancer.

  1. Effect of DPA and 1-MCP on chemical compounds related to superficial scald of Granny Smith apples

    Energy Technology Data Exchange (ETDEWEB)

    Moggia, C.; Moya-Leon, M. A.; Pereira, M.; Yuri, J. A.; Lobos, G. A.

    2010-07-01

    Research was carried out to study the mode of action of diphenylamine (DPA) and 1-methylcyclopropene (1-MCP), on control of superficial scald of Granny Smith apples (Malus domestica Borkh.), and its relation with chemical compounds. Fruit was harvested from a commercial orchard in Chile, 182 and 189 days after full bloom and received the following treatments: DPA (2,000 ppm); 1-MCP (1.2 ppm) and control (no treatment). All fruit was stored for 4 or 6 months at 0 degree centigrade. A completely randomized factorial design was used (2 harvest dates by 3 post harvest treatments). Monthly measurements were made on maturity indices, ethylene production rate (EPR), scald related compounds [a-farnesene (AF), conjugated trienes (CT), total anti-oxidants (AO)], and cell membrane stability. Following 4 and 6 months of storage, plus 7 days at 20 degree centigrade, scald was evaluated. After 6 months, DPA-treated fruit, from both harvests, showed similar firmness, EPR and AO, compared to the control. However, AF and CT were lower, and cell membrane stability higher. Conversely, 1-MCP-treated fruit showed a noticeable EPR suppression and AF inhibition, along with higher firmness, lower CT and AO, compared to the control and DPA. Furthermore, cell membrane stability was superior to that of the control and similar to that of the DPA. Treated fruit (DPA and 1-MCP) showed an important reduction in scald compared to the control. The effect of 1-MCP on the investigated compounds and the reduction in scald, confirms that ethylene plays a major role on its development. (Author) 50 refs.

  2. Antiproton, positron, and electron imaging with a microchannel plate/phosphor detector

    CERN Document Server

    Andresen, G B; Bowe, P D; Bray, C; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Fajans, J; Fujiwara, M C; Gill, D R; Hangst, J S; Hardy, W N; Hayano, R S; Hayden, M E; Humphries, A J; Hydomako, R; Jørgensen, L V; Kerrigan, S J; Kurchaninov, L; Lambo, R; Madsen, N; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Pusa, P; Sarid, E; Seif El Nasr, S; Silveira, D M; Storey, J W; Thompson, R I; van der Werf, D P; Yamazaki, Y

    2009-01-01

    A microchannel plate (MCP)/phosphor screen assembly has been used to destructively measure the radial profile of cold, confined antiprotons, electrons, and positrons in the ALPHA experiment, with the goal of using these trapped particles for antihydrogen creation and confinement. The response of the MCP to low energy (10-200 eV, <1 eV spread) antiproton extractions is compared to that of electrons and positrons.

  3. Design studies for an advanced ECR ion source for multiply charged ion beam generation

    International Nuclear Information System (INIS)

    Alton, G.D.

    1994-01-01

    An innovative technique: for increasing ion source intensity is described which, in principle, could lead to significant advances in ECR ion source technology for multiply charged ion beam formation. The advanced concept design uses a minimum-B magnetic mirror geometry which consists of a multi-cusp, magnetic field, to assist in confining the plasma radially, a flat central field for tuning to the ECR resonant condition, and specially tailored min-or fields in the end zones to confine the plasma in the axial direction. The magnetic field is designed to achieve an axially symmetric plasma ''volume'' with constant mod-B, which extends over the length of the central field region. This design, which strongly contrasts w h the ECR ''surfaces'' characteristic of conventional ECR ion sources, results in dramatic increases in the absorption of RF power, thereby increasing the electron temperature and ''hot'' electron population within the ionization volume of the source

  4. Characterization of photo-multiplier tube as ex-vessel radiation detector in tokamak

    Science.gov (United States)

    Jo, Jungmin; Cheon, MunSeong; Kim, Junghee; An, YoungHwa; Park, Seungil; Chung, Kyoung-Jae; Hwang, Y. S.

    2017-09-01

    Feasibility of using conventional photo-multiplier tubes (PMTs) without a scintillator as an ex-vessel radiation detector in a tokamak environment is studied. Basic irradiation tests using standard gamma ray sources and a d-d neutron generator showed that the PMT is responding both to gamma photons and neutrons, possibly due to the direct generation of secondary electrons inside the PMT by the impingement of high energy photons. Because of the selective sensitivity of the PMT to hard x-ray and neutrons in ohmic and neutral beam injected plasmas, respectively, it is shown that the PMT with certain configuration can be utilized either to monitor the fluctuation in the fusion neutron generation rate or to study the behavior of runaway electrons in tokamaks.

  5. Californium Multiplier. Part I. Design for neutron radiography

    International Nuclear Information System (INIS)

    Crosbie, K.L.; Preskitt, C.A.; John, J.; Hastings, J.D.

    1982-01-01

    The Californium Multiplier (CFX) is a subcritical assembly of enriched uranium surrounding a californium-252 neutron source. The function of the CFX is to multiply the neutrons emitted by the source to a number sufficient for neutron radiography. The CFX is designed to provide a collimated beam of thermal neutrons from which the gamma radiation is filtered, and the scattered neutrons are reduced to make it suitable for high resolution radiography. The entire system has inherent safety features, which provide for system and personnel safety, and it operates at moderate cost. In Part I, the CFX and the theory of its operation are described in detail. Part II covers the performance of the Mound Facility CFX

  6. Generation of fast multiply charged ions in conical targets

    International Nuclear Information System (INIS)

    Demchenko, V.V.; Chukbar, K.V.

    1990-01-01

    So-called conical targets, when the thermonuclear fuel is compressed and heated in a conical cavity in a heavy material (lead, gold, etc.) with the help of a spherical segment that is accelerated by a laser pulse or a beam of charged particles, are often employed in experimental studies of inertial-confinement fusion. In spite of the obvious advantages of such a scheme, one of which is a significant reduction of the required energy input compared with the complete spherical target, it also introduces additional effects into the process of cumulation of energy. In this paper the authors call attention to an effect observed in numerical calculations: the hydrodynamic heating of a small group of multiply charged heavy ions of the walls of the conical cavity up to high energies (T i approx-gt 100 keV). This effect ultimately occurs as a result of the high radiation losses of a multiply charged plasma

  7. Inverse mass matrix via the method of localized lagrange multipliers

    Czech Academy of Sciences Publication Activity Database

    González, José A.; Kolman, Radek; Cho, S.S.; Felippa, C.A.; Park, K.C.

    2018-01-01

    Roč. 113, č. 2 (2018), s. 277-295 ISSN 0029-5981 R&D Projects: GA MŠk(CZ) EF15_003/0000493; GA ČR GA17-22615S Institutional support: RVO:61388998 Keywords : explicit time integration * inverse mass matrix * localized Lagrange multipliers * partitioned analysis Subject RIV: BI - Acoustics OBOR OECD: Applied mechanics Impact factor: 2.162, year: 2016 https://onlinelibrary.wiley.com/doi/10.1002/nme.5613

  8. On Lagrange Multipliers in Work with Quality and Reliability Assurance

    DEFF Research Database (Denmark)

    Vidal, Rene Victor Valqui; Becker, P.

    1986-01-01

    In optimizing some property of a system, reliability say, a designer usually has to accept certain constraints regarding cost, completion time, volume, weight, etc. The solution of optimization problems with boundary constraints can be helped substantially by the use of Lagrange multipliers...... in the areas of sales promotion and teaching. These maps illuminate the logic structure of solution sequences. One such map is shown, illustrating the application of LMT in one of the examples....

  9. Characterization of a prototype matrix of Silicon PhotoMultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Dinu, N. [Laboratory of Linear Accelerator (LAL), IN2P3-CNRS, 91898 Orsay (France)], E-mail: dinu@lal.in2p3.fr; Barrillon, P.; Bazin, C. [Laboratory of Linear Accelerator (LAL), IN2P3-CNRS, 91898 Orsay (France); Belcari, N.; Bisogni, M.G. [Universita di Pisa, Dipartimento di Fisica ' E. Fermi' , 56127 Pisa (Italy); INFN, Sezione di Pisa, 56127 Pisa (Italy); Bondil-Blin, S. [Laboratory of Linear Accelerator (LAL), IN2P3-CNRS, 91898 Orsay (France); Boscardin, M. [Fondazione Bruno Kessler (FBK-irst), 38050 Trento (Italy); Chaumat, V. [Laboratory of Linear Accelerator (LAL), IN2P3-CNRS, 91898 Orsay (France); Collazuol, G. [Scuola Normale Superiore (SNS), 56127 Pisa (Italy); INFN, Sezione di Pisa, 56127 Pisa (Italy); De La Taille, C. [Laboratory of Linear Accelerator (LAL), IN2P3-CNRS, 91898 Orsay (France); Del Guerra, A. [Universita di Pisa, Dipartimento di Fisica ' E. Fermi' , 56127 Pisa (Italy); INFN, Sezione di Pisa, 56127 Pisa (Italy); Llosa, G. [Universita di Pisa, Dipartimento di Fisica ' E. Fermi' , 56127 Pisa (Italy); Marcatili, S. [Universita di Pisa, Dipartimento di Fisica ' E. Fermi' , 56127 Pisa (Italy); INFN, Sezione di Pisa, 56127 Pisa (Italy); Melchiorri, M.; Piemonte, C. [Fondazione Bruno Kessler (FBK-irst), 38050 Trento (Italy); Puill, V. [Laboratory of Linear Accelerator (LAL), IN2P3-CNRS, 91898 Orsay (France); Tarolli, A. [Fondazione Bruno Kessler (FBK-irst), 38050 Trento (Italy); Vagnucci, J.F. [Laboratory of Linear Accelerator (LAL), IN2P3-CNRS, 91898 Orsay (France); Zorzi, N. [Fondazione Bruno Kessler (FBK-irst), 38050 Trento (Italy)

    2009-10-21

    This work reports on the electrical as well as the optical characterizations of a prototype matrix of Silicon PhotoMultipliers (SiPM). The electrical test consists of the measurement of the static (breakdown voltage, quenching resistance, post-breakdown dark current) as well as the dynamic characteristics (gain, dark count rate). The optical test consists of the estimation of the photon detection efficiency as a function of wavelength as well as operation voltage.

  10. Characterization of a prototype matrix of Silicon PhotoMultipliers

    International Nuclear Information System (INIS)

    Dinu, N.; Barrillon, P.; Bazin, C.; Belcari, N.; Bisogni, M.G.; Bondil-Blin, S.; Boscardin, M.; Chaumat, V.; Collazuol, G.; De La Taille, C.; Del Guerra, A.; Llosa, G.; Marcatili, S.; Melchiorri, M.; Piemonte, C.; Puill, V.; Tarolli, A.; Vagnucci, J.F.; Zorzi, N.

    2009-01-01

    This work reports on the electrical as well as the optical characterizations of a prototype matrix of Silicon PhotoMultipliers (SiPM). The electrical test consists of the measurement of the static (breakdown voltage, quenching resistance, post-breakdown dark current) as well as the dynamic characteristics (gain, dark count rate). The optical test consists of the estimation of the photon detection efficiency as a function of wavelength as well as operation voltage.

  11. Radial multipliers on reduced free products of operator algebras

    DEFF Research Database (Denmark)

    Haagerup, Uffe; Møller, Søren

    2012-01-01

    Let AiAi be a family of unital C¿C¿-algebras, respectively, of von Neumann algebras and ¿:N0¿C¿:N0¿C. We show that if a Hankel matrix related to ¿ is trace-class, then there exists a unique completely bounded map M¿M¿ on the reduced free product of the AiAi, which acts as a radial multiplier...

  12. Neutralization of H-- in energetic collisions with multiply charged ions

    International Nuclear Information System (INIS)

    Melchert, F.; Benner, M.; Kruedener, S.; Schulze, R.; Meuser, S.; Huber, K.; Salzborn, E.; Uskov, D.B.; Presnyakov, L.P.

    1995-01-01

    Employing the crossed-beam technique, we have measured absolute cross sections for neutralization of H -- ions in collisions with multiply charged ions Ne q+ (q≤4) and Ar q+ , Xe q+ (q≤8) at center-of-mass energies ranging from 20 to 200 keV. . . It is found that th cross sections are independent of the target ion species. The data are in excellent agreement with quantum calculations. A universal scaling law for the neutralization cross section is given

  13. Estimates for Unimodular Multipliers on Modulation Hardy Spaces

    Directory of Open Access Journals (Sweden)

    Jiecheng Chen

    2013-01-01

    Full Text Available It is known that the unimodular Fourier multipliers eit|Δ|α/2, α>0, are bounded on all modulation spaces Mp,qs for 1≤p,q≤∞. We extend such boundedness to the case of all 00 and obtain the local well-posedness for the Cauchy problem of some nonlinear partial differential equations with fundamental semigroup eit|Δ|α/2.

  14. Safety analysis report for the Neutron Multiplier Facility, 329 Building

    International Nuclear Information System (INIS)

    Rieck, H.G.

    1978-09-01

    Neutron multiplication is a process wherein the flux of a neutron source such as 252 Cf is enhanced by fission reactions that occur in a subcritical assemblage of fissile material. The multiplication factor of the device depends upon the consequences of neutron reactions with matter and is independent of the initial number of neutrons present. Safe utilization of such a device demands that the fissile material assemblage be maintained in a subcritical state throughout all normal and credibly abnormal conditions. Examples of things that can alter the multiplication factor (and degree of subcriticality) are temperature fluctuations, changes in moderator material such as voiding or composition, addition of fissile materials, and change in assembly configuration. The Neutron Multiplier Facility (NMF) utilizes a multiplier- 252 Cf assembly to produce neutrons for activation analysis of organic and inorganic environmental samples and for on-line mass spectrometry analysis of fission products which diffuse from a stationary fissile target (less than or equal to 4 g fissile material) located in the Neutron Multiplier. The NMF annex to the 329 Building provides close proximity to related counting equipment, and delay between sample irradiation and counting is minimized

  15. Neutron fluctuations in a multiplying medium randomly varying in time

    Energy Technology Data Exchange (ETDEWEB)

    Pal, L. [KFKI Atomic Energy Research Inst., Budapest (Hungary); Pazsit, I. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Nuclear Engineering

    2006-07-15

    The master equation approach, which has traditionally been used for the calculation of neutron fluctuations in multiplying systems with constant parameters, is extended to a case when the parameters of the system change randomly in time. A forward type master equation is considered for the case of a multiplying system whose properties jump randomly between two discrete states, both with and without a stationary external source. The first two factorial moments are calculated, including the covariance. This model can be considered as the unification of stochastic methods that were used either in a constant multiplying medium via the master equation technique, or in a fluctuating medium via the Langevin technique. The results obtained show a much richer characteristic of the zero power noise than that in constant systems. The results are relevant in medium power subcritical nuclear systems where the zero power noise is still significant, but they also have a bearing on all types of branching processes, such as evolution of biological systems, spreading of epidemics etc, which are set in a time-varying environment.

  16. Neutron fluctuations in a multiplying medium randomly varying in time

    International Nuclear Information System (INIS)

    Pal, L.; Pazsit, I.

    2006-01-01

    The master equation approach, which has traditionally been used for the calculation of neutron fluctuations in multiplying systems with constant parameters, is extended to a case when the parameters of the system change randomly in time. A forward type master equation is considered for the case of a multiplying system whose properties jump randomly between two discrete states, both with and without a stationary external source. The first two factorial moments are calculated, including the covariance. This model can be considered as the unification of stochastic methods that were used either in a constant multiplying medium via the master equation technique, or in a fluctuating medium via the Langevin technique. The results obtained show a much richer characteristic of the zero power noise than that in constant systems. The results are relevant in medium power subcritical nuclear systems where the zero power noise is still significant, but they also have a bearing on all types of branching processes, such as evolution of biological systems, spreading of epidemics etc, which are set in a time-varying environment

  17. MCP detector read out with a bare quad Timepix at kilohertz frame rates

    International Nuclear Information System (INIS)

    Vallerga, J; Tremsin, A; McPhate, J; Siegmund, O; Raffanti, R

    2011-01-01

    The existing Berkeley neutron sensitive MCP/Timepix hybrid detector has been very successful at demonstrating energy resolved spatial imaging with a single Timepix ASIC read out at a ∼ 30 Hz frame rate where each neutron's position and time (energy) is determined (X,Y,E). By increasing the detector format using a quad arrangement of Timepix readouts and increasing the frame rate to 1 kHz, we can increase our total event throughput by a factor of 120, thereby taking full advantage of the high fluxes of modern pulsed neutron sources (10 6 n cm -2 s -1 ). The key to this conversion is a new design for the ASIC readout, called the Berkeley Quad Timepix detector, consisting of 3 major subsystems. The first is a quad (2 x 2) bare Timepix ASIC board mounted directly behind the neutron sensitive MCPs in a hermetic vacuum enclosure with a sapphire window. The data from the Timepix ASICs flow to the second subsystem called the Interface board whose field programmable gate array (FPGA) rearranges and converts the digital bit stream to LVDS logic levels before sending downstream to the third subsystem, the Roach board. The Roach board is also FPGA based, and takes the data from all the ASICs and analyses the frames to extract information on the input events to pass on to the host PC. This paper describes in detail the hardware and firmware designs to accomplish this task.

  18. The MCP Altona incident: the Canadian regulatory response and framework for the export of uranium

    International Nuclear Information System (INIS)

    Lavoie, Jacques

    2012-01-01

    On 23 December 2010, a cargo ship carrying 350 000 kilograms (kg) of uranium ore concentrates (U 3 O 8 ) belonging to the Canadian resource corporation Cameco left Vancouver, British Columbia, Canada and encountered severe weather conditions between Hawaii and the Midway Islands in international waters en route to Zhanjiang, People's Republic of China (PRC). The ship, the MCP Altona, suffered some damage to its hull but was able to continue to operate through the storm. Once the sea had calmed, the crew noticed that some of the containers on the ship had shifted and had been damaged. The captain, however, was unable to secure the necessary authorizations to obtain safe harbour in the area as there were no signs of immediate risk to the health and safety of the ship's crew. On Cameco's recommendation, the ship returned to British Columbia. This article describes the response of the Canadian Nuclear Safety Commission (CNSC) to this incident. The article also discusses the Canadian policy and regulatory framework for controls on the export of uranium

  19. Ação do 1-metilciclopropeno (1-MCP na vida de prateleira da banana 'maçã' Action of 1-methylcyclopropene (1-MCP on shelf life of 'apple' banana

    Directory of Open Access Journals (Sweden)

    Ana Carla Marques Pinheiro

    2005-04-01

    Full Text Available Objetivou-se avaliar o efeito do 1-metilciclopropeno (1-MCP, em diferentes concentrações, sobre a vida pós-colheita e sob as variáveis associadas aos atributos de qualidade de banana 'Maçã'. Frutos verde-maturos foram submetidos a cinco concentrações de 1-MCP (0; 50; 100; 150 e 200 etaL.L-1, por 12 horas, e foram analisados durante o amadurecimento sob condição ambiente (20±1ºC e 80±5% UR. O tratamento com 50 etaL.L-1 de 1-MCP atrasou o início do amadurecimento das bananas em aproximadamente 8 dias, baseando-se nas primeiras mudanças de coloração da casca, enquanto os tratamentos 100; 150 e 200 etaL.L-1 atrasaram-no em aproximadamente 10 dias. Observou-se, durante o amadurecimento, o amaciamento dos frutos, associado à conversão de amido em açúcares e ao aumento na solubilização péctica e na atividade da pectinametilesterase (PME e poligalacturonase (PG. A aplicação de 50 etaL.L-1de 1-MCP é a mais adequada por promover a extensão da vida de prateleira de bananas 'Maçã', preservando sua qualidade com base nas análises de açúcares solúveis totais, pectinas total e solúvel, firmeza e aparência externa ao final do armazenamento.The objective of this work was to evaluate the influence of the 1-MCP, at different concentrations, on quality and shelf life of 'Apple' banana. Green mature fruits were submitted to five concentrations of 1-MCP (0, 50, 100, 150 and 200 etaL.L-1, for 12 hours and analyzed during the ripening at room temperature (20ºC ± 1 and 80% ± 5 RH . The 1-MCP at 50 etaL.L-1 delayed, in 8 days, the begining of the ripening, based in the first changes of peel color, whereas 100, 150 and 200 etaL.L-1 treatments delayed the begining of the ripening in 10 days, in comparison to the control. The softening of the fruits, associated to the conversion of starch in sugar and the increasing in the pectic solubilization and activity of pectinmethylsterase and polygalacturonase, was observed during the ripening

  20. A new technique for the study of charge transfer in multiply charged ion-ion collisions

    International Nuclear Information System (INIS)

    Shinpaugh, J.L.; Meyer, F.W.; Datz, S.

    1994-01-01

    While large cross sections (>10 -16 cm 2 ) have been predicted for resonant charge transfer in ion-ion collisions, no experimental data exist for multiply charged systems. A novel technique is being developed at the ORNL ECR facility to allow study of symmetric charge exchange in multiply charged ion-ion collisions using a single ion source. Specific intra-beam charge transfer collisions occurring in a well-defined interaction region labeled by negative high voltage are identified and analyzed by electrostatic analysis in combination with ion time-of-flight coincidence detection of the collision products. Center-of-mass collision energies from 400 to 1000 eV are obtained by varying source and labeling-cell voltages. In addition, by the introduction of a target gas into the high-voltage cell, this labeling-voltage method allows measurement of electron-capture and -loss cross sections for ion-atom collisions. Consequently, higher collision energies can be investigated without the requirement of placing the ECR source on a high-voltage platform

  1. Closing of Coster-Kronig transitions in multiply ionised gold atoms

    International Nuclear Information System (INIS)

    Banas, D.; Braziewicz, J.; Czarnota, M.; Fijal, I.; Jaskola, M.; Korman, A.; Kretschmer, W.; Pajek, M.; Semaniak, J.

    2003-01-01

    The paper discusses the effect of closing of L- and M-shell Coster-Kronig (CK) transitions in multiply ionised Au atoms, for which the selected CK transitions become energetically forbidden. This effect plays an important role when the Coster-Kronig energy for single-hole configuration is relatively low, being comparable with a change of the electronic binding energies in multiply ionised atom. We show, by using a simplified model, that for gold the effect of closing of CK transitions occurs for strong L 1 -L 3 M 4,5 transition for the L 1 -subshell as well as the M 3 -M 5 N 6,7 and M 4 -M 5 O 3,4 CK transitions for the M 3 - and M 4 -subshell, respectively. We demonstrate that the discussed effect of closing CK transitions substantially changes the X-ray fluorescence and Coster-Kronig yields and thus has to be considered in interpretation of X-rays excited by heavy ion impact

  2. Crystallization and crystallographic analysis of the ligand-binding domain of the Pseudomonas putida chemoreceptor McpS in complex with malate and succinate

    International Nuclear Information System (INIS)

    Gavira, J. A.; Lacal, J.; Ramos, J. L.; García-Ruiz, J. M.; Krell, T.; Pineda-Molina, E.

    2012-01-01

    The crystallization of the ligand-binding domain of the methyl-accepting chemotaxis protein chemoreceptor McpS (McpS-LBD) is reported. Methyl-accepting chemotaxis proteins (MCPs) are transmembrane proteins that sense changes in environmental signals, generating a chemotactic response and regulating other cellular processes. MCPs are composed of two main domains: a ligand-binding domain (LBD) and a cytosolic signalling domain (CSD). Here, the crystallization of the LBD of the chemoreceptor McpS (McpS-LBD) is reported. McpS-LBD is responsible for sensing most of the TCA-cycle intermediates in the soil bacterium Pseudomonas putida KT2440. McpS-LBD was expressed, purified and crystallized in complex with two of its natural ligands (malate and succinate). Crystals were obtained by both the counter-diffusion and the hanging-drop vapour-diffusion techniques after pre-incubation of McpS-LBD with the ligands. The crystals were isomorphous and belonged to space group C2, with two molecules per asymmetric unit. Diffraction data were collected at the ESRF synchrotron X-ray source to resolutions of 1.8 and 1.9 Å for the malate and succinate complexes, respectively

  3. Monte Carlo Simulations of High-speed, Time-gated MCP-based X-ray Detectors: Saturation Effects in DC and Pulsed Modes and Detector Dynamic Range

    International Nuclear Information System (INIS)

    Kruschwitz, Craig; Ming Wu; Moy, Ken; Rochau, Greg

    2008-01-01

    We present here results of continued efforts to understand the performance of microchannel plate (MCP)-based, high-speed, gated, x-ray detectors. This work involves the continued improvement of a Monte Carlo simulation code to describe MCP performance coupled with experimental efforts to better characterize such detectors. Our goal is a quantitative description of MCP saturation behavior in both static and pulsed modes. We have developed a new model of charge buildup on the walls of the MCP channels and measured its effect on MCP gain. The results are compared to experimental data obtained with a short-pulse, high-intensity ultraviolet laser; these results clearly demonstrate MCP saturation behavior in both DC and pulsed modes. The simulations compare favorably to the experimental results. The dynamic range of the detectors in pulsed operation is of particular interest when fielding an MCP-based camera. By adjusting the laser flux we study the linear range of the camera. These results, too, are compared to our simulations

  4. A new method to measure and increase the detection efficiency of a microchannel plate for 100 keV electrons

    International Nuclear Information System (INIS)

    Tornow, R.P.

    1990-01-01

    A new method is described which permits measurement of efficiency of a microchannel plate (MCP) simply by tracing the output current pulse in the saturated mode. The dependence of the detection efficiency on the gain of the input stages of a detector is calculated and the result is applied to a MCP. Furthermore, an enhancement of the detection efficiency of a MCP is presented for 100 keV electrons up to more than 90% by means of the field-enhanced secondary electron emission. (author)

  5. Correlation of MCP-4 and high-sensitivity C-reactive protein as a marker of inflammation in obesity and chronic periodontitis.

    Science.gov (United States)

    Pradeep, A R; Kumari, Minal; Kalra, Nitish; Priyanka, N

    2013-03-01

    Obesity is increasing in prevalence worldwide and has emerged as a strong risk factor for periodontal disease. Conversely, the remote effects of periodontal disease on various systemic diseases have been proposed. The aim of this study is to determine the presence of MCP-4 and high sensitivity C reactive protein (hsCRP) levels in gingival crevicular fluid (GCF) and serum in obese and non-obese subjects with chronic periodontitis and to find a correlation between MCP-4 and hsCRP in GCF and serum. Forty subjects (20 males and 20 females) were selected and divided into four groups (10 subjects in each group), based on clinical parameters: group NOH (non-obese healthy), group OH (obese healthy), Group NOCP (non-obese with chronic periodontitis) and group OCP (obese with chronic periodontitis). The levels of serum and GCF MCP-4 were determined by ELISA and hsCRP levels were determined by immunoturbidimetry method. The mean GCF and serum concentration of MCP-4 was highest for group OCP followed by group NOCP, group OH (in GCF); group OH, group NOCP(in serum) and least in group NOH. The mean hsCRP concentration was highest for group OCP followed by group OH, group NOCP and group NOH. A significant positive correlation was found between serum and GCF MCP-4 and hsCRP levels. GCF MCP-4 concentrations increased in periodontal disease compared to health and correlated positively with the severity of disease indicating it as a novel marker of periodontal disease. The serum concentration of MCP-4 was found to be more in obese group as compared to nonobese group indicating it as a marker of obesity. Furthermore, based on the positive correlation of MCP-4 and hsCRP found in this study, it can be proposed that MCP-4 and hsCRP may be the markers linking chronic inflammation in obesity and periodontal disease. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Qualidade pós-colheita de quivi 'Hayward' tratado com 1-MCP e armazenado sob diferentes atmosferas

    Directory of Open Access Journals (Sweden)

    Marcelo José Vieira

    2012-06-01

    Full Text Available Este trabalho teve por objetivo avaliar o efeito do 1-MCP sobre o amadurecimento e a qualidade pós-colheita de quivi 'Hayward' armazenado sob diferentes atmosferas. Foram conduzidos dois experimentos, com frutos colhidos em pomar comercial localizado em Fraiburgo-SC. No experimento 1, os frutos foram tratados com três doses de 1-MCP (0,0; 0,5 ou 1,0 µL L-1 e armazenados sob atmosfera controlada (AC, contendo 2,0kPa de O2 + 4,5kPa de CO2, a 0ºC ± 0,5ºC, 92 ± 3% UR, e com <40 ηL L-1 de etileno no ambiente, durante 90 e 120 dias, mais sete dias de vida de prateleira a 23ºC. No experimento 2, os frutos foram tratados com 0,0 ou 0,7 µL L-1 de 1-MCP e armazenados sob atmosfera ambiente (AA, contendo 21 kPa de O2 + 0,03 kPa de CO2, a 0 ± 0,5ºC, 90 ± 3% UR, e com 200 a 250 ηL L-1 de etileno no ambiente, durante 30, 60, 90 e 120 dias, mais um e sete dias de vida de prateleira a 23ºC ou AC (contendo 2,0 kPa de O2 + 4,5 kPa de CO2, a 0ºC ± 0,5ºC, 92 ± 3% UR, e com <40 ηL L-1 de etileno no ambiente, durante 60, 90, 120 e 150 dias, mais um e sete dias de vida de prateleira a 23ºC. Os benefícios do tratamento com 1-MCP sobre a conservação da qualidade foram observados tanto para frutos armazenados sob AA quanto sob AC. No experimento 1, não houve diferença entre as doses de 1-MCP de 0,5 e 1,0 µL L-1 sobre o controle do amadurecimento e manutenção da qualidade dos frutos armazenados em AC. No experimento 2, o tratamento com 1-MCP retardou o aumento na taxa de produção de etileno após remoção de câmara fria. A redução da taxa de produção de etileno nos frutos tratados com 1-MCP foi associada ao aumento na conservação da firmeza da polpa sob AC e AA, e redução na incidência de pericarpo translúcido sob AA. O potencial de armazenamento foi aumentado pelo tratamento com 1-MCP em aproximadamente 60 e 30 dias, nos frutos armazenados sob AA e AC, respectivamente.

  7. EFECTO DEL 1-METILCICLOPROPENO (1-MCP SOBRE LA FISIOLOGÍA Y CALIDAD DE FRUTOS DE JACA (Artocarpus heterophyllus Lam.

    Directory of Open Access Journals (Sweden)

    M. Mata-Montes de Oca

    2007-01-01

    Full Text Available Debido a sus características de color y sabor de pulpa, la demanda de fruta de jaca se ha incrementado considerablemente. La mayoría de la producción de Nayarit es exportada a los Estados Unidos de Norteamérica. Sin embargo, debido a su corta vida de anaquel y susceptibilidad al daño por frío la fruta es exportada vía aérea con altos costos de flete. Se reporta que el 1-Metilciclopropeno (1-MCP retarda el proceso de madurez, alarga la vida de anaquel y mantiene la calidad de varios frutales, así que el objetivo de este estudio fue evaluar el efecto del 1-MCP sobre la fisiología y calidad del fruto de jaca almacenado a 20 ºC. Las frutas fueron cosechadas en madurez fisiológica, lavadas y tratadas con 1-MCP a 100 y 300 nl·litro-1 en cámaras selladas por 12 h a 20 ± 1 ºC; 85 ± 5 % de HR manteniendo un testigo sin tratar. Las variables evaluadas fueron: velocidad de respiración y de producción de etileno, sólidos solubles totales, acidez titulable, firmeza de la pulpa y de la fruta entera, color en la pulpa y pérdida de peso. El 1-MCP no afectó la mayoría de las variables de calidad pero retrasó significativamente la velocidad de respiración y la producción de etileno así como el ablandamiento de la pulpa, lo que permitió prolongar la vida de anaquel hasta por ocho y 12 días a 100 y 300 nl·litro-1, respectivamente.

  8. Aumento da expressão do MCP-1 coroidal e escleral em modelo experimental de hipercolesterolemia

    Directory of Open Access Journals (Sweden)

    Rogil José de Almeida Torres

    2012-02-01

    Full Text Available OBJETIVO: O objetivo deste trabalho é demonstrar experimentalmente que a dieta rica em colesterol provoca aumento da expressão da MCP-1 na coroide e esclera. MÉTODO: Coelhos New Zealand foram organizados em dois grupos: GN (grupo dieta normal, composto por 8 coelhos (8 olhos, recebeu ração padrão para coelhos, durante 4 semanas; GH (grupo hipercolesterolêmico, composto por 13 coelhos (13 olhos, recebeu dieta rica em colesterol a 1% por 8 semanas. Foi realizada a dosagem sérica de colesterol total, triglicerídeos, HDL colesterol, glicemia de jejum no início do experimento e no momento da eutanásia. Ao final da 8ª semana para o GH e 4ª semana para o GN foi realizada a eutanásia dos animais e os olhos foram submetidos à análise imuno-histoquímica com o anticorpo anti-MCP-1. RESULTADOS: A dieta provocou significativo aumento do colesterol total e triglicerídeos do GH em relação ao GN (p<0,001. Houve significativo aumento da expressão da MCP-1 na coroide e esclera dos animais do GH em relação ao GN (p<0,001. CONCLUSÃO: Este estudo demonstrou que a dieta hipercolesterolêmica em coelhos induz ao aumento da expressão do MCP-1 na coroide e esclera.

  9. Spatially and Temporally Regulated NRF2 Gene Therapy Using Mcp-1 Promoter in Retinal Ganglion Cell Injury

    Directory of Open Access Journals (Sweden)

    Kosuke Fujita

    2017-06-01

    Full Text Available Retinal ganglion cell degeneration triggered by axonal injury is believed to underlie many ocular diseases, including glaucoma and optic neuritis. In these diseases, retinal ganglion cells are affected unevenly, both spatially and temporally, such that healthy and unhealthy cells coexist in different patterns at different time points. Herein, we describe a temporally and spatially regulated adeno-associated virus gene therapy aiming to reduce undesired off-target effects on healthy retinal neurons. The Mcp-1 promoter previously shown to be activated in stressed retinal ganglion cells following murine optic nerve injury was combined with the neuroprotective intracellular transcription factor Nrf2. In this model, Mcp-1 promoter-driven NRF2 expression targeting only stressed retinal ganglion cells showed efficacy equivalent to non-selective cytomegalovirus promoter-driven therapy for preventing cell death. However, cytomegalovirus promoter-mediated NRF2 transcription induced cellular stress responses and death of Brn3A-positive uninjured retinal ganglion cells. Such undesired effects were reduced substantially by adopting the Mcp-1 promoter. Combining a stress-responsive promoter and intracellular therapeutic gene is a versatile approach for specifically targeting cells at risk of degeneration. This strategy may be applicable to numerous chronic ocular and non-ocular conditions.

  10. Resposta da aplicação do 1-MCP em frutos de mamoeiro 'Golden' em diferentes estádios de maturação Responses of 1-MCP applications in 'Golden' papaya fruits on differents maturation stages

    Directory of Open Access Journals (Sweden)

    Maximiliano Silva de Souza

    2009-09-01

    Full Text Available O estudo de fatores que influenciam no processo de amadurecimento é fundamental para o planejamento do processo de comercialização, principalmente em frutos com padrão de respiração climatérico e perecível, como é o caso do mamão. Nesse trabalho, avaliou-se o efeito da aplicação do 1-MCP (1-metilciclopropeno sobre o amadurecimento de frutos de mamoeiro nos estádios 0; 1 e 2 de maturação. O 1-MCP diminui a produção de etileno (≈79% e a taxa respiratória (≈45%, principalmente em frutos no estádio 0 de maturação. O uso deste inibidor da ação do etileno retardou a perda de coloração verde da casca dos frutos, principalmente em frutos nos estádios 0 e 1 de maturação. Houve redução na perda de firmeza do fruto e do mesocarpo nos estádios 1 e 2. Entretanto, em frutos no estádio 0 de maturação, a firmeza do mesocarpo manteve-se alta, o que pode comprometer a aceitação destes frutos pelo consumidor. O teor de sólidos solúveis não foi influenciado pela aplicação do 1-MCP. O efeito do 1-MCP na redução da atividade das enzimas PME e PG foi maior em frutos nos estádios 0 e 1 de maturação em comparação a frutos no estádio 2 de maturação. A atividade da PME demonstrou crescente aumento ao longo do período de armazenamento, porém a atividade da PG permaneceu baixa ao longo dos cinco primeiros dias, com aumento posterior. Os resultados mostraram que a PME exerce influência significativa na perda de firmeza da polpa nos primeiros dias, com atuação posterior da PG. O 1-MCP mostrou-se eficiente em retardar o processo de amadurecimento de frutos de mamoeiro, tornando-se mais eficiente quando associado a estádios de maturação iniciais.The study of factors that influence the process of ripening is critical for planning the marketing process, mainly in standard breathing climacteric and perishing fruits, as it is the case of papaya. In this work it was evaluated the effect of the application of 1-MCP (1

  11. Auditing the multiply-related concepts within the UMLS.

    Science.gov (United States)

    Mougin, Fleur; Grabar, Natalia

    2014-10-01

    This work focuses on multiply-related Unified Medical Language System (UMLS) concepts, that is, concepts associated through multiple relations. The relations involved in such situations are audited to determine whether they are provided by source vocabularies or result from the integration of these vocabularies within the UMLS. We study the compatibility of the multiple relations which associate the concepts under investigation and try to explain the reason why they co-occur. Towards this end, we analyze the relations both at the concept and term levels. In addition, we randomly select 288 concepts associated through contradictory relations and manually analyze them. At the UMLS scale, only 0.7% of combinations of relations are contradictory, while homogeneous combinations are observed in one-third of situations. At the scale of source vocabularies, one-third do not contain more than one relation between the concepts under investigation. Among the remaining source vocabularies, seven of them mainly present multiple non-homogeneous relations between terms. Analysis at the term level also shows that only in a quarter of cases are the source vocabularies responsible for the presence of multiply-related concepts in the UMLS. These results are available at: http://www.isped.u-bordeaux2.fr/ArticleJAMIA/results_multiply_related_concepts.aspx. Manual analysis was useful to explain the conceptualization difference in relations between terms across source vocabularies. The exploitation of source relations was helpful for understanding why some source vocabularies describe multiple relations between a given pair of terms. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  12. Fission multipliers for D-D/D-T neutron generators

    International Nuclear Information System (INIS)

    Lou, T.P.; Vujic, J.L.; Koivunoro, H.; Reijonen, J.; Leung, K.-N.

    2003-01-01

    A compact D-D/D-T fusion based neutron generator is being designed at the Lawrence Berkeley National Laboratory to have a potential yield of 10 12 D-D n/s and 10 14 D-T n/s. Because of its high neutron yield and compact size (∼20 cm in diameter by 4 cm long), this neutron generator design will be suitable for many applications. However, some applications required higher flux available from nuclear reactors and spallation neutron sources operated with GeV proton beams. In this study, a subcritical fission multiplier with k eff of 0.98 is coupled with the compact neutron generators in order to increase the neutron flux output. We have chosen two applications to show the gain in flux due to the use of fission multipliers--in-core irradiation and out-of-core irradiation. For the in-core irradiation, we have shown that a gain of ∼25 can be achieved in a positron production system using D-T generator. For the out-of-core irradiation, a gain of ∼17 times is obtained in Boron Neutron Capture Therapy (BNCT) using a D-D neutron generator. The total number of fission neutrons generated by a source neutron in a fission multiplier with k eff is ∼50. For the out-of-core irradiation, the theoretical maximum net multiplication is ∼30 due to the absorption of neutrons in the fuel. A discussion of the achievable multiplication and the theoretical multiplication will be presented in this paper

  13. Spot Pricing When Lagrange Multipliers Are Not Unique

    DEFF Research Database (Denmark)

    Feng, Donghan; Xu, Zhao; Zhong, Jin

    2012-01-01

    Classical spot pricing theory is based on multipliers of the primal problem of an optimal market dispatch, i.e., the solution of the dual problem. However, the dual problem of market dispatch may yield multiple solutions. In these circumstances, spot pricing or any standard pricing practice based...... on a strict extension of the principles of spot pricing and surplus allocation, we propose a new pricing methodology that can yield unique, impartial, and robust solution. The new method has been analyzed and compared with other pricing approaches in accordance with spot pricing theory. Case studies support...

  14. Monte Carlo technique for local perturbations in multiplying systems

    International Nuclear Information System (INIS)

    Bernnat, W.

    1974-01-01

    The use of the Monte Carlo method for the calculation of reactivity perturbations in multiplying systems due to changes in geometry or composition requires a correlated sampling technique to make such calculations economical or in the case of very small perturbations even feasible. The technique discussed here is suitable for local perturbations. Very small perturbation regions will be treated by an adjoint mode. The perturbation of the source distribution due to the changed system and its reaction on the reactivity worth or other values of interest is taken into account by a fission matrix method. The formulation of the method and its application are discussed. 10 references. (U.S.)

  15. Practical model for the calculation of multiply scattered lidar returns

    International Nuclear Information System (INIS)

    Eloranta, E.W.

    1998-01-01

    An equation to predict the intensity of the multiply scattered lidar return is presented. Both the scattering cross section and the scattering phase function can be specified as a function of range. This equation applies when the cloud particles are larger than the lidar wavelength. This approximation considers photon trajectories with multiple small-angle forward-scattering events and one large-angle scattering that directs the photon back toward the receiver. Comparisons with Monte Carlo simulations, exact double-scatter calculations, and lidar data demonstrate that this model provides accurate results. copyright 1998 Optical Society of America

  16. Science with multiply-charged ions at Brookhaven National Laboratory

    International Nuclear Information System (INIS)

    Jones, K.W.; Johnson, B.M.; Meron, M.; Thieberger, P.

    1987-01-01

    The production of multiply-charged heavy ions at Brookhaven National Laboratory and their use in different types of experiments are discussed. The main facilities that are used are the Double MP Tandem Van de Graaff and the National Synchrotron Light Source. The capabilities of a versatile Atomic Physics Facility based on a combination of the two facilities and a possible new heavy-ion storage ring are summarized. It is emphasized that the production of heavy ions and the relevant science necessitates very flexible and diverse apparatus

  17. Chromatographic analysis and purification of multiply tritium-labelled eicosanoids

    International Nuclear Information System (INIS)

    Shevchenko, V.P.; Nagaev, I.Yu.; Myasoedov, N.F.

    1988-01-01

    A comparative study of different chromatographic techniques (gas-liquid (GLC), thin-layer (TLC), liquid (LC), high-pressure liquid (HPLC) chromatography) is presented. They were applied to the analysis and preparative purification of tritium-labelled eicosanoids with a molar radioactivity of 1.8-8.8 TBq/mmol, obtained by selective hydrogenation and by chemical or enzymic methods. The possibility of analyzing reaction mixtures and isolating individual multiply labelled eicosanoids with a chemical and radiochemical purity of 95-98% was demonstrated. Special features of HPLC for high molar radioactivity eicosanoids are considered. (author) 9 refs.; 6 tabs

  18. 233U breeding and neutron multiplying blankets for fusion reactors

    International Nuclear Information System (INIS)

    Cook, A.G.; Maniscalco, J.A.

    1975-01-01

    In this work, along with a previous paper three possible uses of 14-MeV deuterium--tritium fusion neutrons are investigated: energy production, neutron multiplication, and fissile-fuel breeding. The results presented include neutronic studies of fissioning and nonfissioning thorium systems, tritium breeding systems, various fuel options (UO 2 , UC, UC 2 , etc.), and uranium as well as refractory metal first-wall neutron-multiplying regions. A brief energy balance and an estimate of potential revenues for fusion devices are given to help illustrate the potentials of these designs

  19. Determination of Ultimate Torque for Multiply Connected Cross Section Rod

    Directory of Open Access Journals (Sweden)

    V. L. Danilov

    2015-01-01

    Full Text Available The aim of this work is to determine load-carrying capability of the multiply cross-section rod. This calculation is based on the model of the ideal plasticity of the material, so that the desired ultimate torque is a torque at which the entire cross section goes into a plastic state.The article discusses the cylindrical multiply cross-section rod. To satisfy the equilibrium equation and the condition of plasticity simultaneously, two stress function Ф and φ are introduced. By mathematical transformations it has been proved that Ф is constant along the path, and a formula to find its values on the contours has been obtained. The paper also presents the rationale of the line of stress discontinuity and obtained relationships, which allow us to derive the equations break lines for simple interaction of neighboring circuits, such as two lines, straight lines and circles, circles and a different sign of the curvature.After substitution into the boundary condition at the end of the stress function Ф and mathematical transformations a formula is obtained to determine the ultimate torque for the multiply cross-section rod.Using the doubly connected cross-section and three-connected cross-section rods as an example the application of the formula of ultimate torque is studied.For doubly connected cross-section rod, the paper offers a formula of the torque versus the radius of the rod, the aperture radius and the distance between their centers. It also clearly demonstrates the torque dependence both on the ratio of the radii and on the displacement of hole. It is shown that the value of the torque is more influenced by the displacement of hole, rather than by the ratio of the radii.For the three-connected cross-section rod the paper shows the integration feature that consists in selection of a coordinate system. As an example, the ultimate torque is found by two methods: analytical one and 3D modeling. The method of 3D modeling is based on the Nadai

  20. Ionization and bound-state relativistic quantum dynamics in laser-driven multiply charged ions

    International Nuclear Information System (INIS)

    Hetzheim, Henrik

    2009-01-01

    The interaction of ultra-strong laser fields with multiply charged hydrogen-like ions can be distinguished in an ionization and a bound dynamics regime. Both are investigated by means of numerically solving the Dirac equation in two dimensions and by a classical relativistic Monte-Carlo simulation. For a better understanding of highly nonlinear physical processes the development of a well characterized ultra-intense relativistic laser field strength has been driven forward, capable of studying e.g. the magnetic field effects of the laser resulting in an additional electron motion in the laser propagation direction. A novel method to sensitively measure these ultra-strong laser intensities is developed and employed from the optical via the UV towards the XUV frequency regime. In the bound dynamics field, the determination of multiphoton transition matrixelements has been investigated between different bound states via Rabi oscillations. (orig.)

  1. Ionization and bound-state relativistic quantum dynamics in laser-driven multiply charged ions

    Energy Technology Data Exchange (ETDEWEB)

    Hetzheim, Henrik

    2009-01-14

    The interaction of ultra-strong laser fields with multiply charged hydrogen-like ions can be distinguished in an ionization and a bound dynamics regime. Both are investigated by means of numerically solving the Dirac equation in two dimensions and by a classical relativistic Monte-Carlo simulation. For a better understanding of highly nonlinear physical processes the development of a well characterized ultra-intense relativistic laser field strength has been driven forward, capable of studying e.g. the magnetic field effects of the laser resulting in an additional electron motion in the laser propagation direction. A novel method to sensitively measure these ultra-strong laser intensities is developed and employed from the optical via the UV towards the XUV frequency regime. In the bound dynamics field, the determination of multiphoton transition matrixelements has been investigated between different bound states via Rabi oscillations. (orig.)

  2. Design and experimental verification for optical module of optical vector-matrix multiplier.

    Science.gov (United States)

    Zhu, Weiwei; Zhang, Lei; Lu, Yangyang; Zhou, Ping; Yang, Lin

    2013-06-20

    Optical computing is a new method to implement signal processing functions. The multiplication between a vector and a matrix is an important arithmetic algorithm in the signal processing domain. The optical vector-matrix multiplier (OVMM) is an optoelectronic system to carry out this operation, which consists of an electronic module and an optical module. In this paper, we propose an optical module for OVMM. To eliminate the cross talk and make full use of the optical elements, an elaborately designed structure that involves spherical lenses and cylindrical lenses is utilized in this optical system. The optical design software package ZEMAX is used to optimize the parameters and simulate the whole system. Finally, experimental data is obtained through experiments to evaluate the overall performance of the system. The results of both simulation and experiment indicate that the system constructed can implement the multiplication between a matrix with dimensions of 16 by 16 and a vector with a dimension of 16 successfully.

  3. Electronics

    Science.gov (United States)

    2001-01-01

    International Acer Incorporated, Hsin Chu, Taiwan Aerospace Industrial Development Corporation, Taichung, Taiwan American Institute of Taiwan, Taipei, Taiwan...Singapore and Malaysia .5 - 4 - The largest market for semiconductor products is the high technology consumer electronics industry that consumes up...Singapore, and Malaysia . A new semiconductor facility costs around $3 billion to build and takes about two years to become operational

  4. Interaction of singly and multiply charged ions with a lithium-fluoride surface

    International Nuclear Information System (INIS)

    Wirtz, L.

    2001-10-01

    Charge transfer between slow ions and an ionic crystal surface still poses a considerable challenge to theory due to the intrinsic many-body character of the system. For the neutralization of multiply charged ions in front of metal surfaces, the Classical Over the Barrier (COB) model is a widely used tool. We present an extension of this model to ionic crystal surfaces where the localization of valence electrons at the anion sites and the lack of cylindrical symmetry of the ion-surface system impede a simple analytical estimate of electron transfer rates. We use a classical trajectory Monte Carlo approach to calculate electron transfer rates for different charge states of the projectile ion. With these rates we perform a Monte Carlo simulation of the neutralization of slow Ne10+ ions in vertical incidence on an LiF surface. Capture of one or several electrons may lead to a local positive charge up of the surface. The projectile dynamics depends on the balance between the repulsion due to this charge and the attraction due to the self-image potential. In a simulation that treats electronic and nuclear dynamics simultaneously, we show that the image attraction dominates over the repulsive force. Backscattering of very slow multiply charged projectiles high above the surface without touching it ('trampoline effect') does not take place. Instead, the projectile ion penetrates into the surface or is reflected due to close binary collision with surface ions. The case of a singly charged ion in front of an LiF surface is within the reach of ab-initio calculations. We use a multi-configuration self consistent field (MCSCF) and a multi-reference configuration interaction (MR-CI) method to calculate adiabatic potential energy curves for a system consisting of the projectile ion and an embedded cluster of surface ions. With increasing cluster size, the energy levels of the embedded cluster converge towards the band structure of the infinitely extended solid. Due to

  5. Antifungal activity of 1-methylcyclopropene (1-MCP) against anthracnose (Colletotrichum gloeosporioides) in postharvest mango fruit and its possible mechanisms of action.

    Science.gov (United States)

    Xu, Xiangbin; Lei, Huanhuan; Ma, Xiuyan; Lai, Tongfei; Song, Hongmiao; Shi, Xuequn; Li, Jiangkuo

    2017-01-16

    Anthracnose caused by Colletotrichum gloeosporioides is one of the most important postharvest diseases in mango fruit, often causing huge economic losses. In this study, the effect of 1-methylcyclopropene (1-MCP) against anthracnose in postharvest mango fruit and the mechanisms involved were investigated. 1-MCP induced reactive oxygen species (ROS) generation, damaged the mitochondria and destroyed the integrity of plasma membrane of spores of C. gloeosporioides, significantly suppressing spore germination and mycelial growth of C. gloeosporioides. 1-MCP also decreased the decay incidence and lesion expansion of mango fruit caused by C. gloeosporioides. For the first time this study demonstrated that 1-MCP suppressed anthracnose of postharvest mango fruit by directly inhibiting spore germination and mycelial growth of C. gloeosporioides, thus providing a promising strategy for disease control. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Electron-electron Bremsstrahlung for bound target electrons

    International Nuclear Information System (INIS)

    Haug, E.

    2008-01-01

    For the process of electron-electron (e-e) Bremsstrahlung the momentum and energy distributions of the recoiling electrons are calculated in the laboratory frame. In order to get the differential cross section and the photon spectrum for target electrons which are bound to an atom, these formulae are multiplied by the incoherent scattering function and numerically integrated over the recoil energy. The effect of atomic binding is most pronounced at low energies of the incident electrons and for target atoms of high atomic numbers. The results are compared to those of previous calculations. (authors)

  7. Perspective: Electrospray photoelectron spectroscopy: From multiply-charged anions to ultracold anions

    International Nuclear Information System (INIS)

    Wang, Lai-Sheng

    2015-01-01

    Electrospray ionization (ESI) has become an essential tool in chemical physics and physical chemistry for the production of novel molecular ions from solution samples for a variety of spectroscopic experiments. ESI was used to produce free multiply-charged anions (MCAs) for photoelectron spectroscopy (PES) in the late 1990 s, allowing many interesting properties of this class of exotic species to be investigated. Free MCAs are characterized by strong intramolecular Coulomb repulsions, which create a repulsive Coulomb barrier (RCB) for electron emission. The RCB endows many fascinating properties to MCAs, giving rise to meta-stable anions with negative electron binding energies. Recent development in the PES of MCAs includes photoelectron imaging to examine the influence of the RCB on the electron emission dynamics, pump-probe experiments to examine electron tunneling through the RCB, and isomer-specific experiments by coupling PES with ion mobility for biological MCAs. The development of a cryogenically cooled Paul trap has led to much better resolved PE spectra for MCAs by creating vibrationally cold anions from the room temperature ESI source. Recent advances in coupling the cryogenic Paul trap with PE imaging have allowed high-resolution PE spectra to be obtained for singly charged anions produced by ESI. In particular, the observation of dipole-bound excited states has made it possible to conduct vibrational autodetachment spectroscopy and resonant PES, which yield much richer vibrational spectroscopic information for dipolar free radicals than traditional PES

  8. Pseudogenization of the MCP-2/CCL8 chemokine gene in European rabbit (genus Oryctolagus, but not in species of Cottontail rabbit (Sylvilagus and Hare (Lepus

    Directory of Open Access Journals (Sweden)

    van der Loo Wessel

    2012-08-01

    Full Text Available Abstract Background Recent studies in human have highlighted the importance of the monocyte chemotactic proteins (MCP in leukocyte trafficking and their effects in inflammatory processes, tumor progression, and HIV-1 infection. In European rabbit (Oryctolagus cuniculus one of the prime MCP targets, the chemokine receptor CCR5 underwent a unique structural alteration. Until now, no homologue of MCP-2/CCL8a, MCP-3/CCL7 or MCP-4/CCL13 genes have been reported for this species. This is interesting, because at least the first two genes are expressed in most, if not all, mammals studied, and appear to be implicated in a variety of important chemokine ligand-receptor interactions. By assessing the Rabbit Whole Genome Sequence (WGS data we have searched for orthologs of the mammalian genes of the MCP-Eotaxin cluster. Results We have localized the orthologs of these chemokine genes in the genome of European rabbit and compared them to those of leporid genera which do (i.e. Oryctolagus and Bunolagus or do not share the CCR5 alteration with European rabbit (i.e. Lepus and Sylvilagus. Of the Rabbit orthologs of the CCL8, CCL7, and CCL13 genes only the last two were potentially functional, although showing some structural anomalies at the protein level. The ortholog of MCP-2/CCL8 appeared to be pseudogenized by deleterious nucleotide substitutions affecting exon1 and exon2. By analyzing both genomic and cDNA products, these studies were extended to wild specimens of four genera of the Leporidae family: Oryctolagus, Bunolagus, Lepus, and Sylvilagus. It appeared that the anomalies of the MCP-3/CCL7 and MCP-4/CCL13 proteins are shared among the different species of leporids. In contrast, whereas MCP-2/CCL8 was pseudogenized in every studied specimen of the Oryctolagus - Bunolagus lineage, this gene was intact in species of the Lepus - Sylvilagus lineage, and was, at least in Lepus, correctly transcribed. Conclusion The biological function of a gene was often

  9. Multi-MW K-Band Harmonic Multiplier: RF Source For High-Gradient Accelerator R & D

    Science.gov (United States)

    Solyak, N. A.; Yakovlev, V. P.; Kazakov, S. Yu.; Hirshfield, J. L.

    2009-01-01

    A preliminary design is presented for a two-cavity harmonic multiplier, intended as a high-power RF source for use in experiments aimed at developing high-gradient structures for a future collider. The harmonic multiplier is to produce power at selected frequencies in K-band (18-26.5 GHz) using as an RF driver an XK-5 S-band klystron (2.856 GHz). The device is to be built with a TE111 rotating mode input cavity and interchangeable output cavities running in the TEn11 rotating mode, with n = 7,8,9 at 19.992, 22.848, and 25.704 GHz. An example for a 7th harmonic multiplier is described, using a 250 kV, 20 A injected laminar electron beam; with 10 MW of S-band drive power, 4.7 MW of 20-GHz output power is predicted. Details are described of the magnetic circuit, cavities, and output coupler.

  10. Development of high voltage surge limiting resistor for protection of HV multiplier of 3 MeV DC accelerator

    International Nuclear Information System (INIS)

    Dewangan, S.; Sharma, D.K.; Bakhtsingh, R.I.

    2013-01-01

    A 3MeV, 10mA DC electron beam accelerator is in commissioning stages at EBC, Kharghar, Navi Mumbai. The accelerating potential of -3MV is generated by a Parallel Coupled Voltage Multiplier (PCVM) scheme using 74 stages of HV rectifier stacks in the 6 kg/cm 2 SF6 gas environment. The HV surges of order of 600kV, 42kA, 10ns is estimated across the rectifier stacks during sparking in the multiplier column. To limit the surge current and protect the rectifier diodes, a non inductive thick film surge limiting resistor (SLR) and protective spark gap is designed and developed. The rectifier stacks with surge limiting resistors at both the ends and protective spark gap in parallel has been successfully tested in simulated surge condition at an impulse voltage of 212kVp, 150ns FWHM and surge energy of 200J, 10ms, 20kV at 6kg/cm 2 SF6 gas environment and found satisfactorily. Subsequently the HV multiplier was installed with this surge protection scheme and is being tested at 1.2 MeV level. This paper describes the design features and test results of the non-inductive surge limiting resistor. (author)

  11. A High-Speed Design of Montgomery Multiplier

    Science.gov (United States)

    Fan, Yibo; Ikenaga, Takeshi; Goto, Satoshi

    With the increase of key length used in public cryptographic algorithms such as RSA and ECC, the speed of Montgomery multiplication becomes a bottleneck. This paper proposes a high speed design of Montgomery multiplier. Firstly, a modified scalable high-radix Montgomery algorithm is proposed to reduce critical path. Secondly, a high-radix clock-saving dataflow is proposed to support high-radix operation and one clock cycle delay in dataflow. Finally, a hardware-reused architecture is proposed to reduce the hardware cost and a parallel radix-16 design of data path is proposed to accelerate the speed. By using HHNEC 0.25μm standard cell library, the implementation results show that the total cost of Montgomery multiplier is 130 KGates, the clock frequency is 180MHz and the throughput of 1024-bit RSA encryption is 352kbps. This design is suitable to be used in high speed RSA or ECC encryption/decryption. As a scalable design, it supports any key-length encryption/decryption up to the size of on-chip memory.

  12. Imaging moving objects from multiply scattered waves and multiple sensors

    International Nuclear Information System (INIS)

    Miranda, Analee; Cheney, Margaret

    2013-01-01

    In this paper, we develop a linearized imaging theory that combines the spatial, temporal and spectral components of multiply scattered waves as they scatter from moving objects. In particular, we consider the case of multiple fixed sensors transmitting and receiving information from multiply scattered waves. We use a priori information about the multipath background. We use a simple model for multiple scattering, namely scattering from a fixed, perfectly reflecting (mirror) plane. We base our image reconstruction and velocity estimation technique on a modification of a filtered backprojection method that produces a phase-space image. We plot examples of point-spread functions for different geometries and waveforms, and from these plots, we estimate the resolution in space and velocity. Through this analysis, we are able to identify how the imaging system depends on parameters such as bandwidth and number of sensors. We ultimately show that enhanced phase-space resolution for a distribution of moving and stationary targets in a multipath environment may be achieved using multiple sensors. (paper)

  13. Multiplied effect of heat and radiation in chemical stress relaxation

    International Nuclear Information System (INIS)

    Ito, Masayuki

    1981-01-01

    About the deterioration of rubber due to radiation, useful knowledge can be obtained by the measurement of chemical stress relaxation. As an example, the rubber coating of cables in a reactor containment vessel is estimated to be irradiated by weak radiation at the temperature between 60 and 90 deg C for about 40 years. In such case, it is desirable to establish the method of accelerated test of the deterioration. The author showed previously that the law of time-dose rate conversion holds in the case of radiation. In this study, the chemical stress relaxation to rubber was measured by the simultaneous application of heat and radiation, and it was found that there was the multiplied effect of heat and radiation in the stress relaxation speed. Therefore the factor of multiplication of heat and radiation was proposed to describe quantitatively the degree of the multiplied effect. The chloroprene rubber used was offered by Hitachi Cable Co., Ltd. The experimental method and the results are reported. The multiplication of heat and radiation is not caused by the direct cut of molecular chains by radiation, instead, it is based on the temperature dependence of various reaction rates at which the activated species reached the cut of molecular chains through complex reaction mechanism and the temperature dependence of the diffusion rate of oxygen in rubber. (Kako, I.)

  14. Image restorations constrained by a multiply exposed picture

    International Nuclear Information System (INIS)

    Breedlove, J.R. Jr.; Kruger, R.P.; Trussell, H.J.; Hunt, B.R.

    1977-01-01

    There are a number of possible industrial and scientific applications of nanosecond cineradiographs. While the technology exists to produce closely spaced pulses of x rays for this application, the quality of the time-resolved radiographs is severely limited. The limitations arise from the necessity of using a fluorescent screen to convert the transmitted x rays to light and then using electro-optical imaging systems to gate and to record the images with conventional high-speed cameras. It has been proposed that in addition to the time-resolved images, a conventional multiply-exposed radiograph be obtained. Simulations are used to demonstrate that the additional information supplied by the multiply-exposed radiograph can be used to improve the quality of digital image restorations of the time-resolved pictures over what could be achieved with the degraded images alone. Because of the need for image registration and rubber sheet transformations, this problem is one which can best be solved on a digital, as opposed to an optical, computer

  15. Comparative study of main dosimetric characteristics between the GR-200A and MCP-N LiF (Mg, Cu, P) TLD chips

    International Nuclear Information System (INIS)

    Shen Wenxiu; Tang Kaiyong; Wang Shoushan; Cai Gangang; Zhu Hongying; Lu Min

    1999-01-01

    GR-200A and MCP-N are the same kind of LiF(Mg, Cu, P) chip detectors. The main dosimetric characteristics of two LiF (Mg, Cu, P) chip TLDs (GR-200A made in Solid Dosimetric Detector and Method Laboratory, Beijing, and MCP-N made in Poland) are compared, including glow curve structure, TL sensitivity, anti-moisture, reproducibility, background, detection threshold and photosensitivity. Sensitivity of GR-200a is 1.6 times as much as that of MCP-N. The sensitivity of GR-200A is stable after being used for six times, but the sensitivity of MCP-N dropped 2.8%, and its colour turned from white into light brown. The sensitivity and colour of GR-200A did not vary after being stored for 25 days at 98% RH, by comparison the sensitivity of MCP-N dropped 14%, and its colour turned into light brown. It was found that the GR-200A TLD is superior to the MCP-N TLD in above-mentioned characteristics

  16. Postharvest quality of ‘Galaxy’ apples submitted to the treatment with 1-MCP and different cooling times between harvest and cold storage

    Directory of Open Access Journals (Sweden)

    Crizane Hackbarth

    Full Text Available ABSTRACT: In this research it was evaluated if the use of 1-methylcyclopropene (1-MCP, associated to different cooling times between the harvest and storage, replaces the pre-cooling in ‘Galaxy’ apples. Treatments were arranged in a factorial scheme, combining the following factors: application of 1-MCP (with or without and different times between harvest and cooling (24 hours, 96 hours, 144 hours and 192 hours in 2013; and 24 hours, 48 hours, 144 hours and 240 hours in 2014. After four months of cold storage (1.0±0.2°C/92±5% RH - Relative Humidity were evaluated: flesh firmness, texture, titratable acidity (TA, soluble solids (SS and skin color. Apples treated with 1-MCP showed greater flesh firmness, texture and SS, in both years, and more TA and lower incidence of mealy flesh compared to apples not treated with 1-MCP in 2013. The 1-MCP was effective in maintaining the fruit quality, even with the cooling delay of up to 240 hours. Cooling delay of 192 hours and 240 hours in ‘Galaxy’ apples not treated with 1-MCP should be avoided because it reduces the quality of fruits.

  17. Examination of the spatial-response uniformity of a microchannel-plate detector using a pulsed high-voltage electron gun

    International Nuclear Information System (INIS)

    Alumot, D; Kroupp, E; Fisher, A

    2014-01-01

    In this paper we describe an alternative method to examine the spatial-response uniformity of a microchannel-plate (MCP) detector to a ∼ 1 ns pulse of soft x-rays. The examination was performed by illuminating the MCP surface with energetic electrons rather than with x-rays. It is shown that the MCP features similar, yet not identical, response to pulses of soft x-ray photons or energetic electrons, making such examinations much simpler and less expensive. The building of the electron-gun system is relatively easy and inexpensive, and in addition to verifying the spatial uniformity of the response of the MCP to incoming particles and radiation, it can be used to detect damaged areas on the detector. A comparison between the results obtained using the electron-gun with those obtained using a laser-produced-plasma x-ray source, demonstrating the reliability of the method, is presented

  18. An Application of Multiplier Analysis in Analyzing the Role of Mining Sectors on Indonesian National Economy

    Science.gov (United States)

    Subanti, S.; Hakim, A. R.; Hakim, I. M.

    2018-03-01

    This purpose of the current study aims is to analyze the multiplier analysis on mining sector in Indonesia. The mining sectors defined by coal and metal; crude oil, natural gas, and geothermal; and other mining and quarrying. The multiplier analysis based from input output analysis, this divided by income multiplier and output multiplier. This results show that (1) Indonesian mining sectors ranked 6th with contribute amount of 6.81% on national total output; (2) Based on total gross value added, this sector contribute amount of 12.13% or ranked 4th; (3) The value from income multiplier is 0.7062 and the value from output multiplier is 1.2426.

  19. Implementation gap between the theory and practice of biodiversity offset multipliers

    DEFF Research Database (Denmark)

    Bull, Joseph William; Lloyd, Samuel P.; Strange, Niels

    2017-01-01

    literature on multipliers. Then, we collate data on multipliers implemented in practice, rep- resenting the most complete such assessment to date. Finally, we explore remaining design gaps relating to social, ethical, and governance considerations. Multiplier values should theoretically be tens or hundreds...... when considering, for example, ecological uncertainties. We propose even larger multipliers required to satisfy previously ignored considerations – including prospect theory, taboo trades, and power relationships. Conversely, our data analyses show that multipliers are smaller in practice, regularly...... for the implementation gap we have identified. At the same time, there is a need to explore when and where the social, ethical, and governance requirements for NNL reviewed here can be met through approaches other than multipliers....

  20. The Effect of Post-Resistance Exercise Amino Acids on Plasma MCP-1 and CCR2 Expression

    Directory of Open Access Journals (Sweden)

    Adam J. Wells

    2016-07-01

    Full Text Available The recruitment and infiltration of classical monocytes into damaged muscle is critical for optimal tissue remodeling. This study examined the effects of an amino acid supplement on classical monocyte recruitment following an acute bout of lower body resistance exercise. Ten resistance-trained men (24.7 ± 3.4 years; 90.1 ± 11.3 kg; 176.0 ± 4.9 cm ingested supplement (SUPP or placebo (PL immediately post-exercise in a randomized, cross-over design. Blood samples were obtained at baseline (BL, immediately (IP, 30-min (30P, 1-h (1H, 2-h (2H, and 5-h (5H post-exercise to assess plasma concentrations of monocyte chemoattractant protein 1 (MCP-1, myoglobin, cortisol and insulin concentrations; and expressions of C-C chemokine receptor-2 (CCR2, and macrophage-1 antigen (CD11b on classical monocytes. Magnitude-based inferences were used to provide inferences on the true effects of SUPP compared to PL. Changes in myoglobin, cortisol, and insulin concentrations were similar between treatments. Compared to PL, plasma MCP-1 was “very likely greater” (98.1% likelihood effect in SUPP at 2H. CCR2 expression was “likely greater” at IP (84.9% likelihood effect, “likely greater” at 1H (87.7% likelihood effect, “very likely greater” at 2H (97.0% likelihood effect, and “likely greater” at 5H (90.1% likelihood effect in SUPP, compared to PL. Ingestion of SUPP did not influence CD11b expression. Ingestion of an amino acid supplement immediately post-exercise appears to help maintain plasma MCP-1 concentrations and augment CCR2 expression in resistance trained men.

  1. Private Debt Overhang and the Government Spending Multiplier: Evidence for the United States

    OpenAIRE

    Bernardini, Marco; Peersman, Gert

    2015-01-01

    Using state-dependent local projection methods and historical U.S. data, we find that government spending multipliers are considerably larger in periods of private debt overhang. In particular, we find significant crowding-out of personal consumption and investment in low-debt states, resulting in multipliers that are significantly below one. Conversely, in periods of private debt overhang, there is a strong crowding-in effect, while multipliers are much larger than one. In high-debt states, ...

  2. Deflation Expectation Financial System and Decline in Money Multiplier(in Japanese)

    OpenAIRE

    IIDA Yasuyuki

    2005-01-01

    The money multiplier is in a continuous downward trend now since the bubble burst, and, in addition, the trend has accelerated after 2000. It is said that the monetary policy is difficult because the money multiplier has declined. To think about the monetary policy for the future, we should think about the cause of the decline of the money multiplier. I want to verify two typical hypotheses "Deflation Expectation Hypothesis" and "Financial System Hypothesis" for the decision of the money mult...

  3. Extended generalized Lagrangian multipliers for magnetohydrodynamics using adaptive multiresolution methods

    Directory of Open Access Journals (Sweden)

    Domingues M. O.

    2013-12-01

    Full Text Available We present a new adaptive multiresoltion method for the numerical simulation of ideal magnetohydrodynamics. The governing equations, i.e., the compressible Euler equations coupled with the Maxwell equations are discretized using a finite volume scheme on a two-dimensional Cartesian mesh. Adaptivity in space is obtained via Harten’s cell average multiresolution analysis, which allows the reliable introduction of a locally refined mesh while controlling the error. The explicit time discretization uses a compact Runge–Kutta method for local time stepping and an embedded Runge-Kutta scheme for automatic time step control. An extended generalized Lagrangian multiplier approach with the mixed hyperbolic-parabolic correction type is used to control the incompressibility of the magnetic field. Applications to a two-dimensional problem illustrate the properties of the method. Memory savings and numerical divergences of magnetic field are reported and the accuracy of the adaptive computations is assessed by comparing with the available exact solution.

  4. Hardware matrix multiplier/accumulator for lattice gauge theory calculations

    International Nuclear Information System (INIS)

    Christ, N.H.; Terrano, A.E.

    1984-01-01

    The design and operating characteristics of a special-purpose matrix multiplier/accumulator are described. The device is connected through a standard interface to a host PDP11 computer. It provides a set of high-speed, matrix-oriented instructions which can be called from a program running on the host. The resulting operations accelerate the complex matrix arithmetic required for a class of Monte Carlo calculations currently of interest in high energy particle physics. A working version of the device is presently being used to carry out a pure SU(3) lattice gauge theory calculation using a PDP11/23 with a performance twice that obtainable on a VAX11/780. (orig.)

  5. Multiplier ideal sheaves and analytic methods in algebraic geometry

    International Nuclear Information System (INIS)

    Demailly, J.-P.

    2001-01-01

    Our main purpose here is to describe a few analytic tools which are useful to study questions such as linear series and vanishing theorems for algebraic vector bundles. One of the early successes of analytic methods in this context is Kodaira's use of the Bochner technique in relation with the theory of harmonic forms, during the decade 1950-60.The idea is to represent cohomology classes by harmonic forms and to prove vanishing theorems by means of suitable a priori curvature estimates. We pursue the study of L2 estimates, in relation with the Nullstellenstatz and with the extension problem. We show how subadditivity can be used to derive an approximation theorem for (almost) plurisubharmonic functions: any such function can be approximated by a sequence of (almost) plurisubharmonic functions which are smooth outside an analytic set, and which define the same multiplier ideal sheaves. From this, we derive a generalized version of the hard Lefschetz theorem for cohomology with values in a pseudo-effective line bundle; namely, the Lefschetz map is surjective when the cohomology groups are twisted by the relevant multiplier ideal sheaves. These notes are essentially written with the idea of serving as an analytic tool- box for algebraic geometers. Although efficient algebraic techniques exist, our feeling is that the analytic techniques are very flexible and offer a large variety of guidelines for more algebraic questions (including applications to number theory which are not discussed here). We made a special effort to use as little prerequisites and to be as self-contained as possible; hence the rather long preliminary sections dealing with basic facts of complex differential geometry

  6. Multiplier ideal sheaves and analytic methods in algebraic geometry

    Energy Technology Data Exchange (ETDEWEB)

    Demailly, J -P [Universite de Grenoble I, Institut Fourier, Saint-Martin d' Heres (France)

    2001-12-15

    Our main purpose here is to describe a few analytic tools which are useful to study questions such as linear series and vanishing theorems for algebraic vector bundles. One of the early successes of analytic methods in this context is Kodaira's use of the Bochner technique in relation with the theory of harmonic forms, during the decade 1950-60.The idea is to represent cohomology classes by harmonic forms and to prove vanishing theorems by means of suitable a priori curvature estimates. We pursue the study of L2 estimates, in relation with the Nullstellenstatz and with the extension problem. We show how subadditivity can be used to derive an approximation theorem for (almost) plurisubharmonic functions: any such function can be approximated by a sequence of (almost) plurisubharmonic functions which are smooth outside an analytic set, and which define the same multiplier ideal sheaves. From this, we derive a generalized version of the hard Lefschetz theorem for cohomology with values in a pseudo-effective line bundle; namely, the Lefschetz map is surjective when the cohomology groups are twisted by the relevant multiplier ideal sheaves. These notes are essentially written with the idea of serving as an analytic tool- box for algebraic geometers. Although efficient algebraic techniques exist, our feeling is that the analytic techniques are very flexible and offer a large variety of guidelines for more algebraic questions (including applications to number theory which are not discussed here). We made a special effort to use as little prerequisites and to be as self-contained as possible; hence the rather long preliminary sections dealing with basic facts of complex differential geometry.

  7. Multiply charged ions from solid substances with the mVINIS Ion Source

    International Nuclear Information System (INIS)

    Dragani, I; Nedeljkovi, T; Jovovi, J; Siljegovic, M; Dobrosavljevic, A

    2007-01-01

    We have used the well known metal-ions-from-volatile-compounds (MIVOC) method at the mVINIS Ion Source to produce the multiply charged ion beams form solid substances. Based on this method the very intense and stable multiply charged ion beams of several solid substances having the high melting points were extracted. The ion yields and the spectra of multiply charged ion beams obtained from solid materials like Fe and Hf will be presented. We have utilized the multiply charged ion beams from solid substances to irradiate the polymers, fullerenes and glassy carbon at the low energy channel for modification of materials

  8. Increased Eotaxin and MCP-1 Levels in Serum from Individuals with Periodontitis and in Human Gingival Fibroblasts Exposed to Pro-Inflammatory Cytokines

    Science.gov (United States)

    Sulniute, Rima; Palmqvist, Py; Majster, Mirjam; Holm, Cecilia Koskinen; Zwicker, Stephanie; Clark, Reuben; Önell, Sebastian; Johansson, Ingegerd; Lerner, Ulf H.; Lundberg, Pernilla

    2015-01-01

    Periodontitis is a chronic inflammatory disease of tooth supporting tissues resulting in periodontal tissue destruction, which may ultimately lead to tooth loss. The disease is characterized by continuous leukocyte infiltration, likely mediated by local chemokine production but the pathogenic mechanisms are not fully elucidated. There are no reliable serologic biomarkers for the diagnosis of periodontitis, which is today based solely on the degree of local tissue destruction, and there is no available biological treatment tool. Prompted by the increasing interest in periodontitis and systemic inflammatory mediators we mapped serum cytokine and chemokine levels from periodontitis subjects and healthy controls. We used multivariate partial least squares (PLS) modeling and identified monocyte chemoattractant protein-1 (MCP-1) and eotaxin as clearly associated with periodontitis along with C-reactive protein (CRP), years of smoking and age, whereas the number of remaining teeth was associated with being healthy. Moreover, body mass index correlated significantly with serum MCP-1 and CRP, but not with eotaxin. We detected higher MCP-1 protein levels in inflamed gingival connective tissue compared to healthy but the eotaxin levels were undetectable. Primary human gingival fibroblasts displayed strongly increased expression of MCP-1 and eotaxin mRNA and protein when challenged with tumor necrosis factor-α (TNF-α and interleukin-1β (IL-1β), key mediators of periodontal inflammation. We also demonstrated that the upregulated chemokine expression was dependent on the NF-κΒ pathway. In summary, we identify higher levels of CRP, eotaxin and MCP-1 in serum of periodontitis patients. This, together with our finding that both CRP and MCP-1 correlates with BMI points towards an increased systemic inflammatory load in patients with periodontitis and high BMI. Targeting eotaxin and MCP-1 in periodontitis may result in reduced leukocyte infiltration and inflammation in

  9. MCP-1/CCR-2-double-deficiency severely impairs the migration of hematogenous inflammatory cells following transient cerebral ischemia in mice.

    Science.gov (United States)

    Schuette-Nuetgen, Katharina; Strecker, Jan-Kolja; Minnerup, Jens; Ringelstein, E Bernd; Schilling, Matthias

    2012-02-01

    Monocyte chemoattractant protein-1 (MCP-1) and its receptor CCR-2 are known to play a major role in inflammatory responses after cerebral ischemia. Mice deficient in either MCP-1 or CCR-2 have been reported to develop smaller infarct sizes and show decreased numbers of infiltrating inflammatory cells. In the present study we used green fluorescent protein (GFP) transgenic mice to investigate the effect of MCP-1/CCR-2-double deficiency on the recruitment of inflammatory cells in a model of both, mild and severe cerebral ischemia. We show that MCP-1/CCR-2-double deficiency virtually entirely abrogates the recruitment of hematogenous macrophages and significantly reduces neutrophil migration to the ischemic brain 4 and 7 days following focal cerebral ischemia. This argues for a predominant role of the MCP-1/CCR-2 axis in chemotaxis of monocytes despite a wide redundancy in the chemokine-receptor-system. Chemokine analysis revealed that even candidates known to be involved in monocyte and neutrophil recruitment like MIP-1α, CXCL-1, C5a, G-CSF and GM-CSF showed a reduced and delayed or even a lack of relevant compensatory response in MCP-1(-/-)/CCR-2(-/-)-mice. Solely, chemokine receptor 5 (CCR-5) increased early in both, but rose above wildtype levels at day 7 in MCP-1(-/-)/CCR-2(-/-)-animals, which might explain the higher number of activated microglial cells compared to control mice. Our study was, however, not powered to investigate infarct volumes. Further studies are needed to clarify whether these mechanisms of inflammatory cell recruitment might be essential for early infarct development and final infarct size and to evaluate potential therapeutic implications. Copyright © 2011 Elsevier Inc. All rights reserved.

  10. Joint effect of MCP-1 genotype GG and MMP-1 genotype 2G/2G increases the likelihood of developing pulmonary tuberculosis in BCG-vaccinated individuals.

    Directory of Open Access Journals (Sweden)

    Malathesha Ganachari

    2010-01-01

    Full Text Available We previously reported that the -2518 MCP-1 genotype GG increases the likelihood of developing tuberculosis (TB in non-BCG-vaccinated Mexicans and Koreans. Here, we tested the hypothesis that this genotype, alone or together with the -1607 MMP-1 functional polymorphism, increases the likelihood of developing TB in BCG-vaccinated individuals. We conducted population-based case-control studies of BCG-vaccinated individuals in Mexico and Peru that included 193 TB cases and 243 healthy tuberculin-positive controls from Mexico and 701 TB cases and 796 controls from Peru. We also performed immunohistochemistry (IHC analysis of lymph nodes from carriers of relevant two-locus genotypes and in vitro studies to determine how these variants may operate to increase the risk of developing active disease. We report that a joint effect between the -2518 MCP-1 genotype GG and the -1607 MMP-1 genotype 2G/2G consistently increases the odds of developing TB 3.59-fold in Mexicans and 3.9-fold in Peruvians. IHC analysis of lymph nodes indicated that carriers of the two-locus genotype MCP-1 GG MMP-1 2G/2G express the highest levels of both MCP-1 and MMP-1. Carriers of these susceptibility genotypes might be at increased risk of developing TB because they produce high levels of MCP-1, which enhances the induction of MMP-1 production by M. tuberculosis-sonicate antigens to higher levels than in carriers of the other two-locus MCP-1 MMP-1 genotypes studied. This notion was supported by in vitro experiments and luciferase based promoter activity assay. MMP-1 may destabilize granuloma formation and promote tissue damage and disease progression early in the infection. Our findings may foster the development of new and personalized therapeutic approaches targeting MCP-1 and/or MMP-1.

  11. Joint effect of MCP-1 genotype GG and MMP-1 genotype 2G/2G increases the likelihood of developing pulmonary tuberculosis in BCG-vaccinated individuals.

    Science.gov (United States)

    Ganachari, Malathesha; Ruiz-Morales, Jorge A; Gomez de la Torre Pretell, Juan C; Dinh, Jeffrey; Granados, Julio; Flores-Villanueva, Pedro O

    2010-01-25

    We previously reported that the -2518 MCP-1 genotype GG increases the likelihood of developing tuberculosis (TB) in non-BCG-vaccinated Mexicans and Koreans. Here, we tested the hypothesis that this genotype, alone or together with the -1607 MMP-1 functional polymorphism, increases the likelihood of developing TB in BCG-vaccinated individuals. We conducted population-based case-control studies of BCG-vaccinated individuals in Mexico and Peru that included 193 TB cases and 243 healthy tuberculin-positive controls from Mexico and 701 TB cases and 796 controls from Peru. We also performed immunohistochemistry (IHC) analysis of lymph nodes from carriers of relevant two-locus genotypes and in vitro studies to determine how these variants may operate to increase the risk of developing active disease. We report that a joint effect between the -2518 MCP-1 genotype GG and the -1607 MMP-1 genotype 2G/2G consistently increases the odds of developing TB 3.59-fold in Mexicans and 3.9-fold in Peruvians. IHC analysis of lymph nodes indicated that carriers of the two-locus genotype MCP-1 GG MMP-1 2G/2G express the highest levels of both MCP-1 and MMP-1. Carriers of these susceptibility genotypes might be at increased risk of developing TB because they produce high levels of MCP-1, which enhances the induction of MMP-1 production by M. tuberculosis-sonicate antigens to higher levels than in carriers of the other two-locus MCP-1 MMP-1 genotypes studied. This notion was supported by in vitro experiments and luciferase based promoter activity assay. MMP-1 may destabilize granuloma formation and promote tissue damage and disease progression early in the infection. Our findings may foster the development of new and personalized therapeutic approaches targeting MCP-1 and/or MMP-1.

  12. Aspergillus antigen induces robust Th2 cytokine production, inflammation, airway hyperreactivity and fibrosis in the absence of MCP-1 or CCR2

    Directory of Open Access Journals (Sweden)

    Charo Israel F

    2004-09-01

    Full Text Available Abstract Background Asthma is characterized by type 2 T-helper cell (Th2 inflammation, goblet cell hyperplasia, airway hyperreactivity, and airway fibrosis. Monocyte chemoattractant protein-1 (MCP-1 or CCL2 and its receptor, CCR2, have been shown to play important roles in the development of Th2 inflammation. CCR2-deficient mice have been found to have altered inflammatory and physiologic responses in some models of experimental allergic asthma, but the role of CCR2 in contributing to inflammation and airway hyperreactivity appears to vary considerably between models. Furthermore, MCP-1-deficient mice have not previously been studied in models of experimental allergic asthma. Methods To test whether MCP-1 and CCR2 are each required for the development of experimental allergic asthma, we applied an Aspergillus antigen-induced model of Th2 cytokine-driven allergic asthma associated with airway fibrosis to mice deficient in either MCP-1 or CCR2. Previous studies with live Aspergillus conidia instilled into the lung revealed that MCP-1 and CCR2 play a role in anti-fungal responses; in contrast, we used a non-viable Aspergillus antigen preparation known to induce a robust eosinophilic inflammatory response. Results We found that wild-type C57BL/6 mice developed eosinophilic airway inflammation, goblet cell hyperplasia, airway hyperreactivity, elevations in serum IgE, and airway fibrosis in response to airway challenge with Aspergillus antigen. Surprisingly, mice deficient in either MCP-1 or CCR2 had responses to Aspergillus antigen similar to those seen in wild-type mice, including production of Th2 cytokines. Conclusion We conclude that robust Th2-mediated lung pathology can occur even in the complete absence of MCP-1 or CCR2.

  13. Multiply charged negative ions of hydrogen in linearly polarized laser fields

    International Nuclear Information System (INIS)

    van Duijn, E.; Muller, H.G.

    1997-01-01

    Motivated by the prediction of the appearance of atomic multiply charged negative ions (AMCNI) of hydrogen, induced by a linearly polarized laser field, we present an analytical quantum mechanical treatment of the appearance and structure of AMCNI in a linearly polarized field, based on high-frequency Floquet theory (HFFT). For the simplest AMCNI of hydrogen, H 2- and H 3- , the values of α 0 at which the first bound state appears are α 0 =1.62x10 2 and α 0 =1.02x10 4 , where α 0 =I 1/2 /ω 2 is the amplitude of the oscillation of a free electron in the field with frequency ω and intensity I (unless stated otherwise, we use atomic units throughout this paper). Whereas in vacuum at least one of the electrons of an AMCNI autodetaches, an intense high-frequency field can change the character of the ion dramatically, such that bound states of AMCNI can appear. Due to the interaction with the field, the electrons of the AMCNI oscillate in phase along the polarization axis. This open-quotes quiverclose quotes motion enables the electrons to be spatially separated over distances of order α 0 , reducing the repulsive e-e interaction as α 0 increases. In other words, for α 0 large enough, the field enables a configuration in which the electrons, while widely separated, are bound to one proton. For the prediction of bound states of H N- with N>3, however, a relativistic description or low-frequency theory is required. copyright 1997 The American Physical Society

  14. High-harmonic electron bunching in the field of a signal wave and the use of this effect in cyclotron masers with frequency multiplication

    Directory of Open Access Journals (Sweden)

    I. V. Bandurkin

    2005-01-01

    Full Text Available A method of organizing electron-wave interaction at the multiplied frequency of the signal wave is proposed. This type of electron-wave interaction provides multiplied-frequency electron bunching, which leads to formation of an intense harmonic of the electron current at a selected multiplied frequency of the signal wave. This effect is attractive for the use in klystron-type cyclotron masers with frequency multiplication as a way to increase the output frequency and improve the selectivity.

  15. EFECTO DEL EMPAQUE Y DEL 1-MCP SOBRE CARACTERÍSTICAS FÍSICAS, QUÍMICAS Y FISIOLÓGICAS DE PITAHAYA AMARILLA EFEITO DA EMBALAGEM E DO 1-MCP SOB AS PROPRIEDADES QUÍMICAS, FÍSICAS E FISIOLÓGICAS DA PITAHAYA AMARELA EFFECT OF PACKAGING AND 1-MCP ON PHYSICAL, CHEMICAL AND PHYSIOLOGICAL CHARACTERISTICS OF PITAHAYA YELLOW

    Directory of Open Access Journals (Sweden)

    LILIANA SERNA C

    2011-12-01

    Full Text Available En pitahaya amarilla entera con grado de madurez 3, se evaluó el efecto del empaque (canastillas plásticas y cajas de cartón tipo exportación y la aplicación de soluciones acuosas de 1-Metilciclopropeno (200 y 400 µgL-1, sobre la pérdida de peso, firmeza, color, sólidos solubles, acidez titulable, tasa respiratoria y tiempo de vida comercial. Se encontró que en los dos empaques, la aplicación de soluciones acuosas de 200 y 400 µgL-1 de 1-Metilciclopropeno (1-MCP disminuyó los cambios en acidez, tasa respiratoria y color, sin embargo, aumentó la pérdida de peso durante el almacenamiento. El tipo de empaque afectó significativamente la pérdida de peso, los sólidos solubles y el color. La aplicación de 200 µgL-1 de 1-MCP generó menor variación en la luminosidad y en la coloración verde-amarilla en la fruta. Concentraciones de 200 y 400 µgL-1 de 1-MCP y el empaque en canastillas plásticas para mercado local permitieron prolongar el tiempo de vida comercial de la pitahaya amarilla 3 días. Los resultados de este estudio confirman además que la pitahaya amarilla es una fruta climatérica.Na pitahaya amarela inteira com grau tres de madures, foi avallado os efeitos da embalagem (cestos de plástico e caixas de papelão tipo exportação e a aplicação de soluções aquosas de 1-metilciclopropeno (200 e 400 µgL-1 sobre a perda de peso, firmeza, cor, teor de sólidos solúveis totais, acidez, taxa de respiração e tempo de vida comercial. Foi observado que nas duas embalagens, a aplicação de soluções aquosas de 200 e 400 µgL-1 de 1-Metilciclopropeno (1-MCP reduziu as variações na acidez, taxa de respiração e cor, no entanto, aumentou a perda de peso durante o armazenamento. 0 tipo da embalagem afetou significativamente a perda de peso, o teor de sólidos solúveis totais, e acor. A aplicação de 200 µgL-1 de 1-MCP gerou menor variação na luminosidade e na cor verde-amarela no fruto. Concentrações de 200 e 400

  16. Prokaryotic expression and in vitro functional analysis of IL-1β and MCP-1 from guinea pig.

    Science.gov (United States)

    Dirisala, Vijaya R; Jeevan, Amminikutty; Ly, Lan H; McMurray, David N

    2013-06-01

    The Guinea pig (Cavia porcellus) is an excellent animal model for studying human tuberculosis (TB) and also for a number of other infectious and non-infectious diseases. One of the major roadblocks in effective utilization of this animal model is the lack of readily available immunological reagents. In order to address this issue, guinea pig interleukin 1 beta (IL-1β) and monocyte chemoattractant protein-1 (MCP-1) were efficiently cloned and expressed in a prokaryotic expression vector, and the expressed proteins in soluble form from both the genes were confirmed by N-terminal sequencing. The biological activity of recombinant guinea pig IL-1β was demonstrated by its ability to drive proliferation in thymocytes, and the recombinant guinea pig MCP-1 exhibited chemotactic activity for guinea pig resident peritoneal macrophages. These biologically active recombinant guinea pig proteins will facilitate an in-depth understanding of the role they play in the immune responses of the guinea pig to TB and other diseases.

  17. PEG-albumin plasma expansion increases expression of MCP-1 evidencing increased circulatory wall shear stress: an experimental study.

    Directory of Open Access Journals (Sweden)

    C Makena Hightower

    Full Text Available Treatment of blood loss with plasma expanders lowers blood viscosity, increasing cardiac output. However, increased flow velocity by conventional plasma expanders does not compensate for decreased viscosity in maintaining vessel wall shear stress (WSS, decreasing endothelial nitric oxide (NO production. A new type of plasma expander using polyethylene glycol conjugate albumin (PEG-Alb causes supra-perfusion when used in extreme hemodilution and is effective in treating hemorrhagic shock, although it is minimally viscogenic. An acute 40% hemodilution/exchange-transfusion protocol was used to compare 4% PEG-Alb to Ringer's lactate, Dextran 70 kDa and 6% Hetastarch (670 kDa in unanesthetized CD-1 mice. Serum cytokine analysis showed that PEG-Alb elevates monocyte chemotactic protein-1 (MCP-1, a member of a small inducible gene family, as well as expression of MIP-1α, and MIP-2. MCP-1 is specific to increased WSS. Given the direct link between increased WSS and production of NO, the beneficial resuscitation effects due to PEG-Alb plasma expansion appear to be due to increased WSS through increased perfusion and blood flow rather than blood viscosity.

  18. Muscle glycogen depletion following 75-km of cycling is not linked to increased muscle IL-6, IL-8, and MCP-1 mRNA expression and protein content

    Directory of Open Access Journals (Sweden)

    David Christopher Nieman

    2016-09-01

    Full Text Available The cytokine response to heavy exertion varies widely for unknown reasons, and this study evaluated the relative importance of glycogen depletion, muscle damage, and stress hormone changes on blood and muscle cytokine measures. Cyclists (N=20 participated in a 75-km cycling time trial (168±26.0 min, with blood and vastus lateralis muscle samples collected before and after. Muscle glycogen decreased 77.2±17.4%, muscle IL-6, IL-8, and MCP-1 mRNA increased 18.5±2.8-, 45.3±7.8-, and 8.25±1.75-fold, and muscle IL-6, IL-8, and MCP-1 protein increased 70.5±14.1%, 347±68.1%, and 148±21.3%, respectively (all, P<0.001. Serum myoglobin and cortisol increased 32.1±3.3 to 242±48.3 mg/mL, and 295±27.6 to 784±63.5 nmol/L, respectively (both P<0.001. Plasma IL-6, IL-8, and MCP-1 increased 0.42±0.07 to 18.5±3.8, 4.07±0.37 to 17.0±1.8, and 96.5±3.7 to 240±21.6 pg/mL, respectively (all P<0.001. Increases in muscle IL-6, IL-8, and MCP-1 mRNA were unrelated to any of the outcome measures. Muscle glycogen depletion was related to change in plasma IL-6 (r=0.462, P=0.040, with change in myoglobin related to plasma IL-8 (r=0.582, P=0.007 and plasma MCP-1 (r=0.457, P=0.043, and muscle MCP-1 protein (r=0.588, P=0.017; cortisol was related to plasma IL-8 (r=0.613, P=0.004, muscle IL-8 protein (r=0.681, P=0.004, and plasma MCP-1 (r=0.442, P=0.050. In summary, this study showed that muscle IL-6, IL-8, and MCP-1 mRNA expression after 75-km cycling was unrelated to glycogen depletion and muscle damage, with change in muscle glycogen related to plasma IL-6, and changes in serum myoglobin and cortisol related to the chemotactic cytokines IL-8 and MCP-1.

  19. Correlation of serum MCP-1 and VE-cadherin levels with neural function and carotid atherosclerosis in patients with acute cerebral infarction

    Directory of Open Access Journals (Sweden)

    Yan-Bing Xi

    2017-05-01

    Full Text Available Objective: To study the correlation of serum monocyte chemoattractant protein-1 (MCP-1 and vascular endothelial cadherin (VE-cadherin levels with neural function and carotid atherosclerosis in patients with acute cerebral infarction. Methods: A total of 78 patients who were diagnosed with acute cerebral infarction in our hospital between May 2013 and August 2016 were selected as pathological group, and 80 healthy volunteers who received physical examination in our hospital during the same period were selected as control group. Serum was collected to determine the levels of MCP-1, VE-cadherin, nerve injury molecules, inflammatory mediators, proteases and their hydrolysate. Results: Serum MCP-1, VE-cadherin, NGB, NSE, S100β, HMGB-1, sCD40L, YKL-40, visfatin, CatK, MMP9 and ICTP levels of pathological group were significantly higher than those of control group; serum MCP-1 and VE-cadherin levels of pathological group were positively correlated with NGB, NSE, S100β, HMGB-1, sCD40L, YKL-40, visfatin, CatK, MMP9 and ICTP levels. Conclusion: Serum MCP-1 and VE-cadherin levels abnormally increase in patients with acute cerebral infarction, and are closely related to the nerve injury and atherosclerosis process.

  20. The Ultraviolet Surprise. Efficient Soft X-Ray High Harmonic Generation in Multiply-Ionized Plasmas

    International Nuclear Information System (INIS)

    Popmintchev, Dimitar; Hernandez-Garcia, Carlos; Dollar, Franklin; Mancuso, Christopher; Perez-Hernandez, Jose A.; Chen, Ming-Chang; Hankla, Amelia; Gao, Xiaohui; Shim, Bonggu; Gaeta, Alexander L.; Tarazkar, Maryam; Romanov, Dmitri A.; Levis, Robert J.; Gaffney, Jim A.; Foord, Mark; Libby, Stephen B.; Jaron-Becker, Agnieskzka; Becker, Andreas; Plaja, Luis; Muranane, Margaret M.; Kapteyn, Henry C.; Popmintchev, Tenio

    2015-01-01

    High-harmonic generation is a universal response of matter to strong femtosecond laser fields, coherently upconverting light to much shorter wavelengths. Optimizing the conversion of laser light into soft x-rays typically demands a trade-off between two competing factors. Reduced quantum diffusion of the radiating electron wave function results in emission from each species which is highest when a short-wavelength ultraviolet driving laser is used. But, phase matching - the constructive addition of x-ray waves from a large number of atoms - favors longer-wavelength mid-infrared lasers. We identified a regime of high-harmonic generation driven by 40-cycle ultraviolet lasers in waveguides that can generate bright beams in the soft x-ray region of the spectrum, up to photon energies of 280 electron volts. Surprisingly, the high ultraviolet refractive indices of both neutral atoms and ions enabled effective phase matching, even in a multiply ionized plasma. We observed harmonics with very narrow linewidths, while calculations show that the x-rays emerge as nearly time-bandwidt-limited pulse trains of ~100 attoseconds

  1. Line Emission and X-ray Line Polarization of Multiply Ionized Mo Ions

    Science.gov (United States)

    Petkov, E. E.; Safronova, A. S.; Kantsyrev, V. L.; Shlyaptseva, V. V.; Stafford, A.; Safronova, U. I.; Shrestha, I. K.; Schultz, K. A.; Childers, R.; Cooper, M. C.; Beiersdorfer, P.; Hell, N.; Brown, G. V.

    2016-10-01

    We present a comprehensive experimental and theoretical study of the line emission from multiply ionized Mo ions produced by two different sets of experiments: at LLNL EBIT and the pulsed power generator Zebra at UNR. Mo line emission and polarization measurements were accomplished at EBIT for the first time. In particular, benchmarking experiments at the LLNL EBIT with Mo ions produced at electron beam energies from 2.75 keV up to 15 keV allowed us to break down these very complicated spectra into spectra with only few ionization stages and to select processes that influence them as well as to measure line polarization. The EBIT data were recorded using the EBIT Calorimeter Spectrometer and a crystal spectrometer with a Ge crystal. X-ray Mo spectra and pinhole images were collected from Z-pinch plasmas produced from various wire loads. Non-LTE modeling, high-precision relativistic atomic and polarization data were used to analyze L-shell Mo spectra. The influence of different plasma processes including electron beams on Mo line radiation is summarized. This work was supported by NNSA under DOE Grant DE-NA0002954. Experiments at the NTF/UNR were funded in part by DE-NA0002075. Work at LLNL was performed under the auspices of the U.S. DOE under contract DE-AC52-07NA27344.

  2. The role of the [CpM(CO)2](-) chromophore in the optical properties of the [Cp2ThMCp(CO)2](+) complexes, where M = Fe, Ru and Os. A theoretical view.

    Science.gov (United States)

    Cantero-López, Plinio; Le Bras, Laura; Páez-Hernández, Dayán; Arratia-Pérez, Ramiro

    2015-12-14

    The chemical bond between actinide and the transition metal unsupported by bridging ligands is not well characterized. In this paper we study the electronic properties, bonding nature and optical spectra in a family of [Cp2ThMCp(CO)2](+) complexes where M = Fe, Ru, Os, based on the relativistic two component density functional theory calculations. The Morokuma-Ziegler energy decomposition analysis shows an important ionic contribution in the Th-M interaction with around 25% of covalent character. Clearly, charge transfer occurs on Th-M bond formation, however the orbital term most likely represents a strong charge rearrangement in the fragments due to the interaction. Finally the spin-orbit-ZORA calculation shows the possible NIR emission induced by the [FeCp(CO)2](-) chromophore accomplishing the antenna effect that justifies the sensitization of the actinide complexes.

  3. Jacobi's last multiplier and symmetries for the Kepler problem plus a lineal story

    International Nuclear Information System (INIS)

    Nucci, M C; Leach, P G L

    2004-01-01

    We calculate the first integrals of the Kepler problem by the method of Jacobi's last multiplier using the symmetries for the equations of motion. Also we provide another example which shows that Jacobi's last multiplier together with Lie symmetries unveils many first integrals neither necessarily algebraic nor rational whereas other published methods may yield just one

  4. The long-run relationship between the Japanese credit and money multipliers

    OpenAIRE

    Mototsugu Fukushige

    2013-01-01

    The standard argument is that while money creation and credit creation have different channels, they provide the same theoretical size of multipliers. However, there is usually some difference in practice. Consequently, in this paper we investigate the long-run relationship between the credit and money multipliers in Japan.

  5. A microchannel plate X-ray multiplier with rising-time less than 170 ps

    International Nuclear Information System (INIS)

    Zhao Shicheng; Ouyang Bin

    1987-01-01

    The time reponse of a microchannel plate X-ray multiplier has been improved considerably by using a coupling construction of coaxial tapers. The experimental calibration results with laser plasma X-ray source show that the rising-time of the multiplier is less than 170 ps

  6. Fragmentation study of isolated and nano-solvated biomolecules induced by collision with multiply charged ions and neutral particles

    International Nuclear Information System (INIS)

    Bernigaud, V.

    2009-01-01

    This thesis concerns a gas phase study of the fragmentation of bio-molecular systems induced by slow collisions with multiply charged ions (in the keV-region), alkali atoms and rare gases. The main objective was to study the physical processes involved in the dissociation of highly electronically excited systems. In order to elucidate the intrinsic properties of certain biomolecules (porphyrins and amino acids) we have performed experiments in the gas phase with isolated systems. The obtained results demonstrate the high stability of porphyrins after electron removal and attachment. Furthermore, a dependence of the fragmentation pattern produced by multiply charged ions on the isomeric structure of the alanine molecule has been shown. In a second part of the thesis, a strong influence of the environment of the biomolecule on the fragmentation channels, their modification and their new opening, has been clearly proven. This phenomenon occurs in the presence of other surrounding biomolecules (clusters of nucleobases) as well as for molecules of a solvent (molecules of water, methanol and acetonitrile) in which the biomolecule is embedded. In order to extend these studies to larger systems, a new experimental set-up, based on an electro-spray ion source combined with a quadrupole mass filter has been developed. Due to the successful tests and proposed improvements of the device future experiments will become available concerning the fragmentation of large charged and solvated bio-molecular systems induced by collision processes. (author) [fr

  7. Area efficient radix 4/sup 2/ 64 point pipeline fft architecture using modified csd multiplier

    International Nuclear Information System (INIS)

    Siddiq, F.; Muhammad, T.; Iqbal, M.

    2014-01-01

    A modified Fast Fourier Transform (FFT) based radix 42 algorithm for Orthogonal Frequency Division Multiplexing (OFDM) systems is presented. When compared with similar schemes like Canonic signed digit (CSD) Constant Multiplier, the modified CSD multiplier can provide a improvement of more than 36% in terms of multiplicative complexity. In Comparison of area being occupied the amount of Full adders is reduced by 32% and amount of half adders is reduced by 42%. The modified CSD multiplier scheme is implemented on Xilinx ISE 10.1 using Spartan-III XC3S1000 FPGA as a target device. The synthesis results of modified CSD Multiplier on Xilinx show efficient Twiddle Factor ROM Design and effective area reduction in comparison to CSD constant multiplier. (author)

  8. Multiply-Imputed Synthetic Data: Advice to the Imputer

    Directory of Open Access Journals (Sweden)

    Loong Bronwyn

    2017-12-01

    Full Text Available Several statistical agencies have started to use multiply-imputed synthetic microdata to create public-use data in major surveys. The purpose of doing this is to protect the confidentiality of respondents’ identities and sensitive attributes, while allowing standard complete-data analyses of microdata. A key challenge, faced by advocates of synthetic data, is demonstrating that valid statistical inferences can be obtained from such synthetic data for non-confidential questions. Large discrepancies between observed-data and synthetic-data analytic results for such questions may arise because of uncongeniality; that is, differences in the types of inputs available to the imputer, who has access to the actual data, and to the analyst, who has access only to the synthetic data. Here, we discuss a simple, but possibly canonical, example of uncongeniality when using multiple imputation to create synthetic data, which specifically addresses the choices made by the imputer. An initial, unanticipated but not surprising, conclusion is that non-confidential design information used to impute synthetic data should be released with the confidential synthetic data to allow users of synthetic data to avoid possible grossly conservative inferences.

  9. Time-division-multiplex control scheme for voltage multiplier rectifiers

    Directory of Open Access Journals (Sweden)

    Bin-Han Liu

    2017-03-01

    Full Text Available A voltage multiplier rectifier with a novel time-division-multiplexing (TDM control scheme for high step-up converters is proposed in this study. In the proposed TDM control scheme, two full-wave voltage doubler rectifiers can be combined to realise a voltage quadrupler rectifier. The proposed voltage quadrupler rectifier can reduce transformer turn ratio and transformer size for high step-up converters and also reduce voltage stress for the output capacitors and rectifier diodes. An N-times voltage rectifier can be straightforwardly produced by extending the concepts from the proposed TDM control scheme. A phase-shift full-bridge (PSFB converter is adopted in the primary side of the proposed voltage quadrupler rectifier to construct a PSFB quadrupler converter. Experimental results for the PSFB quadrupler converter demonstrate the performance of the proposed TDM control scheme for voltage quadrupler rectifiers. An 8-times voltage rectifier is simulated to determine the validity of extending the proposed TDM control scheme to realise an N-times voltage rectifier. Experimental and simulation results show that the proposed TDM control scheme has great potential to be used in high step-up converters.

  10. A Novel and Efficient Hardware Implementation of Scalar Point Multiplier

    Directory of Open Access Journals (Sweden)

    M. Masoumi

    2012-12-01

    Full Text Available A new and highly efficient architecture for elliptic curve scalar point multiplication is presented. To achieve the maximum architectural and timing improvements we have reorganized and reordered the critical path of the Lopez-Dahab scalar point multiplication architecture such that logic structures are implemented in parallel and operations in the critical path are diverted to noncritical paths. The results we obtained show that with G = 55 our proposed design is able to compute GF(2163 elliptic curve scalar multiplication in 9.6 μs with the maximum achievable frequency of 250 MHz on Xilinx Virtex-4 (XC4VLX200, where G is the digit size of the underlying digit-serial finite field multiplier. Another implementation variant for less resource consumption is also proposed. With G=33, the design performs the same operation in 11.6 μs at 263 MHz on the same platform. The results of synthesis show that in the first implementation 17929 slices or 20% of the chip area is occupied which makes it suitable for speed critical cryptographic applications while in the second implementation 14203 slices or 16% of the chip area is utilized which makes it suitable for applications that may require speed-area trade-off. The new design shows superior performance compared to the previously reported designs.

  11. DQM: Decentralized Quadratically Approximated Alternating Direction Method of Multipliers

    Science.gov (United States)

    Mokhtari, Aryan; Shi, Wei; Ling, Qing; Ribeiro, Alejandro

    2016-10-01

    This paper considers decentralized consensus optimization problems where nodes of a network have access to different summands of a global objective function. Nodes cooperate to minimize the global objective by exchanging information with neighbors only. A decentralized version of the alternating directions method of multipliers (DADMM) is a common method for solving this category of problems. DADMM exhibits linear convergence rate to the optimal objective but its implementation requires solving a convex optimization problem at each iteration. This can be computationally costly and may result in large overall convergence times. The decentralized quadratically approximated ADMM algorithm (DQM), which minimizes a quadratic approximation of the objective function that DADMM minimizes at each iteration, is proposed here. The consequent reduction in computational time is shown to have minimal effect on convergence properties. Convergence still proceeds at a linear rate with a guaranteed constant that is asymptotically equivalent to the DADMM linear convergence rate constant. Numerical results demonstrate advantages of DQM relative to DADMM and other alternatives in a logistic regression problem.

  12. Storage of strawberries (Fragaria ananassa L. cv. ‘Oso Grande’, subjected to 1-MCP - doi: 10.4025/actascitechnol.v34i3.8790

    Directory of Open Access Journals (Sweden)

    Polyanna Alves Silva

    2012-05-01

    Full Text Available This study aimed to investigate the influence of 1 - methylcyclopropene (1-MCP on the substances involved in the softening of strawberry, cultivar Oso Grande, stored at room temperature, from the municipality of Itutinga, State of Minas Gerais. The parameters evaluated were: firmness, total pectin, percentage of solubilization, activities of the enzymes pectinmethylesterase (PME (EC 3.1.1.11 and polygalacturonase (PG (EC 3.2.1.15. It was concluded that 1-MCP delayed the softening of the fruits, since the fruits that were treated with 1-MCP after storage, have shown greater firmness, lower activities of PG and PME, and lower contents of total pectin, soluble pectin and percentage of solubilization. 

  13. Increased cerebrospinal fluid levels of cytokines monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1β (MIP-1β) in patients with amyotrophic lateral sclerosis.

    Science.gov (United States)

    Martínez, H R; Escamilla-Ocañas, C E; Camara-Lemarroy, C R; González-Garza, M T; Moreno-Cuevas, J; García Sarreón, M A

    2017-10-10

    Neuroinflammation has recently been described in amyotrophic lateral sclerosis (ALS). However, the precise role of such proinflammatory cytokines as monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1β (MIP-1β) in ALS has not yet been determined. In this study, we determined cerebrospinal fluid (CSF) MCP-1 and MIP-1β levels and assessed their association with the duration and severity of ALS. Concentrations of MCP-1 and MIP-1β were determined in the CSF of 77 patients diagnosed with ALS and 13 controls. Cytokine levels were analysed in relation to ALS duration (12months) and severity (30points on the ALS Functional Rating Scale administered at hospital admission). Higher CSF MIP-1β (10.68pg/mL vs. 4.69pg/mL, P<.0001) and MCP-1 (234.89pg/mL vs. 160.95pg/mL, P=.011) levels were found in the 77 patients with ALS compared to controls. There were no differences in levels of either cytokine in relation to disease duration or severity. However, we did observe a significant positive correlation between MIP-1β and MCP-1 in patients with ALS. The increase in MIP-1β and MCP-1 levels suggests that these cytokines may have a synergistic effect on ALS pathogenesis. However, in our cohort, no association was found with either the duration or the clinical severity of the disease. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. Nuclear NF-κB p65 in peripheral blood mononuclear cells correlates with urinary MCP-1, RANTES and the severity of type 2 diabetic nephropathy.

    Directory of Open Access Journals (Sweden)

    Bin Yi

    Full Text Available AIMS: To investigate if nuclear NF-κB p65 expression in ex vivo isolated peripheral blood mononuclear cells correlates with urinary MCP-1 or RANTES and the severity of type 2 diabetic nephropathy. METHODS: According to their urinary albumin-to-creatinine ratio (uACR, 107 patients with type 2 diabetes (eGFR >60 ml/min were divided into normal albuminuria group (DN0 group, 38 cases, microalbuminuria group (DN1 group, 38 cases, and macroalbuminuria group (DN2 group, 31 cases, compared with matched healthy normal control group (NC group, 30 cases. Nuclear NF-κB p65 protein expression levels in peripheral blood mononuclear cells were detected by western blotting. Real-time quantitative polymerase chain reaction was used to detect NF-κB p65 mRNA expression and ELISA assay was used to detect the levels of urinary MCP-1 and RANTES. RESULTS: Nuclear NF-κB p65 protein and NF-κB p65 mRNA expression levels in peripheral blood mononuclear cells, urinary MCP-1/Cr and RANTES/Cr were all significantly higher in all diabetes groups as compared with NC group. In particular, the increase of nuclear NF-κB p65 protein and NF-κB p65 mRNA expressions, urinary MCP-1/Cr and RANTES/Cr all correlated with the severity of type 2 diabetic nephropathy as indicated by the increase in uACR. Pearson correlation analysis indicated that both urinary MCP-1/Cr and RANTES/Cr were positively correlated with nuclear NF-κB p65 protein or NF-κB p65 mRNA levels. Stepwise multiple regression analysis showed that nuclear NF-κB p65 protein or NF-κB p65 mRNA was an independent variable for urinary MCP-1/Cr, and MCP-1/Cr and RANTES/Cr were two independent variables for uACR. CONCLUSION: Our research demonstrates that nuclear NF-κB p65 protein and mRNA expressions in ex vivo isolated peripheral blood mononuclear cells well correlate with urinary MCP-1/Cr, RANTES/Cr and the severity of type 2 diabetic nephropathy.

  15. Qualidade de caqui 'Rama forte' após armazenamento refrigerado, influenciada pelos tratamentos 1-MCP e/ou CO2

    Directory of Open Access Journals (Sweden)

    João Peterson Pereira Gardin

    2012-12-01

    Full Text Available Avaliaram-se os efeitos dos tratamentos com CO2 e 1-MCP (1-metilciclopropeno sobre a adstringência (índice de tanino, firmeza da polpa e distúrbios da epiderme em caqui 'Rama Forte'. Frutos foram tratados com 1-MCP por 24 h, logo após a colheita e/ou com alto CO2 (70% por 24 ou 48 h, um dia após a colheita ou após o armazenamento refrigerado (AR. Os caquis foram armazenados sob atmosfera modificada a 0 ºC, por 45 dias, e a seguir mantidos a 23 ºC, por 9 dias. Frutos-controle (não tratados com 1-MCP nem com CO2 amoleceram em três dias e perderam aproximadamente 50% da adstringência em 6 dias após o AR. A exposição ao CO2 acelerou a redução da adstringência. Esse efeito do CO2 foi menor em frutos tratados com 1-MCP, especialmente quando o CO2 foi aplicado após o AR, por apenas 24 h. O tratamento com 1-MCP inibiu o amolecimento e a redução da adstringência, especialmente nos frutos não tratados com CO2. O amolecimento de frutos tratados com 1-MCP foi maior quando a exposição ao CO2 ocorreu antes do AR. A combinação dos tratamentos com 1-MCP e alto CO2 reduziu a incidência de podridões e manchas translúcidas, mas não alterou o desenvolvimento de pintas pretas ('estrias'. Os resultados indicam que é possível induzir perda da adstringência sem excessiva perda da firmeza da polpa de caquis 'Rama Forte' após o AR pela associação dos tratamentos com 1-MCP logo após a colheita e alto CO2 após o AR.

  16. Development of a new fast shower maximum detector based on microchannel plates photomultipliers (MCP-PMT) as an active element

    Energy Technology Data Exchange (ETDEWEB)

    Ronzhin, A., E-mail: ronzhin@fnal.gov [Fermilab, Batavia, IL 60510 (United States); Los, S.; Ramberg, E. [Fermilab, Batavia, IL 60510 (United States); Spiropulu, M.; Apresyan, A.; Xie, S. [California Institute of Technology, Pasadena, CA (United States); Kim, H. [University of Chicago, Chicago, IL 60637 (United States); Zatserklyaniy, A. [University of California, Santa Cruz, CA (United States)

    2014-09-21

    One possibility to make a fast and radiation resistant shower maximum (SM) detector is to use a secondary emitter as an active element. We present below test beam results, obtained with different types of photodetectors based on microchannel plates (MCPs) as the secondary emitter. We performed the measurements at the Fermilab Test Beam Facility with 120 GeV proton beam and 12 GeV and 32 GeV secondary beams. The goal of the measurement with 120 GeV protons was to determine time resolution for minimum ionizing particles (MIPs). The SM time resolution we obtained for this new type of detector is at the level of 20–30 ps. We estimate that a significant contribution to the detector response originates from secondary emission of the MCP. This work can be considered as the first step in building a new type of calorimeter based on this principle.

  17. Genetic polymorphisms of RANTES, IL1-A, MCP-1 and TNF-A genes in patients with prostate cancer

    International Nuclear Information System (INIS)

    Sáenz-López, Pablo; Carretero, Rafael; Cózar, José Manuel; Romero, José Maria; Canton, Julia; Vilchez, José Ramón; Tallada, Miguel; Garrido, Federico; Ruiz-Cabello, Francisco

    2008-01-01

    Inflammation has been implicated as an etiological factor in several human cancers, including prostate cancer. Allelic variants of the genes involved in inflammatory pathways are logical candidates as genetic determinants of prostate cancer risk. The purpose of this study was to investigate whether single nucleotide polymorphisms of genes that lead to increased levels of pro-inflammatory cytokines and chemokines are associated with an increased prostate cancer risk. A case-control study design was used to test the association between prostate cancer risk and the polymorphisms TNF-A-308 A/G (rs 1800629), RANTES-403 G/A (rs 2107538), IL1-A-889 C/T (rs 1800587) and MCP-1 2518 G/A (rs 1024611) in 296 patients diagnosed with prostate cancer and in 311 healthy controls from the same area. Diagnosis of prostate cancer was significantly associated with TNF-A GA + AA genotype (OR, 1.61; 95% CI, 1.09–2.64) and RANTES GA + AA genotype (OR, 1.44; 95% CI, 1.09–2.38). A alleles in TNF-A and RANTES influenced prostate cancer susceptibility and acted independently of each other in these subjects. No epistatic effect was found for the combination of different polymorphisms studied. Finally, no overall association was found between prostate cancer risk and IL1-A or MCP-1 polymorphisms. Our results and previously published findings on genes associated with innate immunity support the hypothesis that polymorphisms in proinflammatory genes may be important in prostate cancer development

  18. Configurable multiplier modules for an adaptive computing system

    Directory of Open Access Journals (Sweden)

    O. A. Pfänder

    2006-01-01

    Full Text Available The importance of reconfigurable hardware is increasing steadily. For example, the primary approach of using adaptive systems based on programmable gate arrays and configurable routing resources has gone mainstream and high-performance programmable logic devices are rivaling traditional application-specific hardwired integrated circuits. Also, the idea of moving from the 2-D domain into a 3-D design which stacks several active layers above each other is gaining momentum in research and industry, to cope with the demand for smaller devices with a higher scale of integration. However, optimized arithmetic blocks in course-grain reconfigurable arrays as well as field-programmable architectures still play an important role. In countless digital systems and signal processing applications, the multiplication is one of the critical challenges, where in many cases a trade-off between area usage and data throughput has to be made. But the a priori choice of word-length and number representation can also be replaced by a dynamic choice at run-time, in order to improve flexibility, area efficiency and the level of parallelism in computation. In this contribution, we look at an adaptive computing system called 3-D-SoftChip to point out what parameters are crucial to implement flexible multiplier blocks into optimized elements for accelerated processing. The 3-D-SoftChip architecture uses a novel approach to 3-dimensional integration based on flip-chip bonding with indium bumps. The modular construction, the introduction of interfaces to realize the exchange of intermediate data, and the reconfigurable sign handling approach will be explained, as well as a beneficial way to handle and distribute the numerous required control signals.

  19. Theory of Pulsed Neutron Experiments in Highly Heterogeneous Multiplying Media

    International Nuclear Information System (INIS)

    Corno, S.E.

    1965-01-01

    In this work we investigate the time and space dependence of the neutron flux within a highly heterogeneous assembly, in which pulsed or sinusoidally modulated neutrons are injected. We consider, for the sake of simplicity, a device consisting of a cylindrical block of heavy moderator, along the axis of which a line-shaped region of fissionable material is located. The driving neutron source is assumed to be located on one of the end faces of the cylinder. The extent of the fissionable region allows us to deal with it as with an absorbing and multiplying singularity of the neutron field. As our attention is mostly concentrated on space and time variation of the neutron flux, rather crude approximations are assumed as far as the energy dependence of the neutron population is concerned. Within the limits of the age-diffusion theory, the response of the device to any neutron excitation may be found in closed form. For a sinusoidally modulated source of given frequency, it may easily be shown that, if the axial singularity were a purely absorbing one, the neutron waves being propagated along the device would possess a phase shift; a wavelength and an attenuation constant depending on the absorbing properties of the singularity. This picture becomes more and more complicated when neutron multiplication occurs. For this general case the solution derived in our paper obviously turns out to be dependent on both absorption and multiplication properties of the singularity. This circumstance suggests, among others, the idea of using a device of the type described above for testing fuel elements of heterogeneous reactors. (author) [fr

  20. Permeability criteria for effective function of passive countercurrent multiplier.

    Science.gov (United States)

    Layton, H E; Knepper, M A; Chou, C L

    1996-01-01

    The urine concentrating effect of the mammalian renal inner medulla has been attributed to countercurrent multiplication of a transepithelial osmotic difference arising from passive absorption of NaCl from thin ascending limbs of long loops of Henle. This study assesses, both mathematically and experimentally, whether the permeability criteria for effective function of this passive hypothesis are consistent with transport properties measured in long loops of Henle of chinchilla. Mathematical simulations incorporating loop of Henle transepithelial permeabilities idealized for the passive hypothesis generated a steep inner medullary osmotic gradient, confirming the fundamental feasibility of the passive hypothesis. However, when permeabilities measured in chinchilla were used, no inner medullary gradient was generated. A key parameter in the apparent failure of the passive hypothesis is the long-loop descending limb (LDL) urea permeability, which must be small to prevent significant transepithelial urea flux into inner medullary LDL. Consequently, experiments in isolated perfused thin LDL were conducted to determine whether the urea permeability may be lower under conditions more nearly resembling those in the inner medulla. LDL segments were dissected from 30-70% of the distance along the inner medullary axis of the chinchilla kidney. The factors tested were NaCl concentration (125-400 mM in perfusate and bath), urea concentration (5-500 mM in perfusate and bath), calcium concentration (2-8 mM in perfusate and bath), and protamine concentration (300 micrograms/ml in perfusate). None of these factors significantly altered the measured urea permeability, which exceeded 20 x 10(-5) cm/s for all conditions. Simulation results show that this moderately high urea permeability in LDL is an order of magnitude too high for effective operation of the passive countercurrent multiplier.

  1. Effect of the equity multiplier indicator in companies according the sectors

    Directory of Open Access Journals (Sweden)

    Lenka Lízalová

    2013-01-01

    Full Text Available Managers carry out the demand of the owners to maximise the rentability of invested capital with regards to the taken risk. The tool that evaluates the suitability to indebt in order to reach a higher rentability is the equity multiplier indicator. An analysis of the multiplier was carried out on 10 years of data from 456 Czech companies. Based on the data from these companies the influence of two components of the multiplier, which characterise the influence of indebtedness on the return on equity, was analysed. These components are “financial leverage” and “interest burden”, these having an antagonistic effect. The low variability of the equity multiplier is apparent in the companies of the administrative and support service sector and it is also relatively low in the companies of the agriculture, forestry and fishing sector; on the contrary, in for example the professional, scientific and technical activities and the sector of water, sewage and waste there are companies with higher variability of the equity multiplier. The paper identifies companies (in view of their sector specialization inclining to a larger utility of debts to increase the return on equity. The largest equity is reached in companies of the construction sector; the lowest effect of the multiplier is to be found in companies of the agriculture sector. The resulting value of the multiplier is to a large extent determined by the financial leverage indicator, to a lower extent and at the same time negatively by the interest burden indicator.

  2. Low energy electron microscopy imaging using Medipix2 detector

    International Nuclear Information System (INIS)

    Sikharulidze, I.; Gastel, R. van; Schramm, S.; Abrahams, J.P.; Poelsema, B.; Tromp, R.M.; Molen, S.J. van der

    2011-01-01

    Low Energy Electron Microscopy (LEEM) and Photo-Emission Electron Microscopy (PEEM) predominantly use a combination of microchannel plate (MCP), phosphor screen and optical camera to record images formed by 10-20 keV electrons. We have tested the performance of a LEEM/PEEM instrument with a Medipix2 hybrid pixel detector using an Ir(1 1 1) sample with graphene flakes grown on its surface. We find that Medipix2 offers a number of advantages over the MCP. The adjustable threshold settings allow Medipix2 to operate as a noiseless detector, offering an improved signal-to-noise ratio for the same amount of signal compared to the MCP. At the same magnification Medipix2 images exhibit superior resolution and can handle significantly higher electron current densities than an MCP, offering the prospect of substantially higher frame rates in LEEM imaging. These factors make Medipix2 an excellent candidate to become the detector of choice for LEEM/PEEM applications.

  3. Low energy electron microscopy imaging using Medipix2 detector

    Energy Technology Data Exchange (ETDEWEB)

    Sikharulidze, I., E-mail: irakli@chem.leidenuniv.nl [Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300RA Leiden (Netherlands); Gastel, R. van [MESA Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500AE Enschede (Netherlands); Schramm, S. [Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9504, 2300RA Leiden (Netherlands); Abrahams, J.P. [Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300RA Leiden (Netherlands); Poelsema, B. [MESA Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500AE Enschede (Netherlands); Tromp, R.M. [Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9504, 2300RA Leiden (Netherlands); IBM Research Division, T. J. Watson Research Center, P.O. Box 218, Yorktown Heights, NY 10598 (United States); Molen, S.J. van der [Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9504, 2300RA Leiden (Netherlands)

    2011-05-15

    Low Energy Electron Microscopy (LEEM) and Photo-Emission Electron Microscopy (PEEM) predominantly use a combination of microchannel plate (MCP), phosphor screen and optical camera to record images formed by 10-20 keV electrons. We have tested the performance of a LEEM/PEEM instrument with a Medipix2 hybrid pixel detector using an Ir(1 1 1) sample with graphene flakes grown on its surface. We find that Medipix2 offers a number of advantages over the MCP. The adjustable threshold settings allow Medipix2 to operate as a noiseless detector, offering an improved signal-to-noise ratio for the same amount of signal compared to the MCP. At the same magnification Medipix2 images exhibit superior resolution and can handle significantly higher electron current densities than an MCP, offering the prospect of substantially higher frame rates in LEEM imaging. These factors make Medipix2 an excellent candidate to become the detector of choice for LEEM/PEEM applications.

  4. The effect of geometric scattering on the oscillatory magnetoconductance in multiply connected disordered mesoscopic rings

    International Nuclear Information System (INIS)

    Basu, C.; Gu Benyuan.

    1994-12-01

    We present the quantum mechanical calculations on the conductance of a quantum waveguide consisting of multiply connected mesoscopic rings with disordered ring-circumferences and ballistic lead connections between the rings with the transfer matrix approach. The profiles of the conductance as functions of the magnetic flux and the Fermi wave number of electrons depend on the number of rings as also on the geometric configuration of the system. The conductance spectrum of this system for disordered ring circumferences, disordered ring intervals and disordered magnetic flux is examined in detail. Studying the effect of geometric scattering and the two different length scales involved in the network, namely, the ring circumference and the ballistic lead connections on the conductance profile, we find that there exist two kinds of mini-bands, one originating from the bound states of the rings, i.e. the intrinsic mini-bands, and the other associated with the connecting leads between the adjacent rings, which are the extra mini-bands. These two kinds of mini-bands respond differently to external perturbations in parameters. Unlike the system of potential scatterers, this system of geometric scatterers show complete band formations at all energies even for finite systems and there is a preferential decay of the energy states depending upon the type of disorder introduced. The conductance band structures strongly depend on the geometric configuration of the network and so by controlling the geometric parameters, the conductance band structures can be artificially tailored. (author). 18 refs, 6 figs

  5. Chemokine MCP1/CCL2 and RANTES/CCL5 gene polymorphisms influence Henoch–Schönlein purpura susceptibility and severity

    Directory of Open Access Journals (Sweden)

    Hsin-Hui Yu

    2015-04-01

    Conclusion: Our results support the fact that chemokines play important roles in the pathogenesis of HSP. MCP1/CCL2 gene polymorphisms were associated with susceptibility for HSP. RANTES/CCL5 gene polymorphisms may be related to disease severity and HSP nephritis.

  6. Concentrações de IL-6, TNF-α e MCP-1 em crianças com excesso de massa corporal

    Directory of Open Access Journals (Sweden)

    Juliano Magalhães Guedes

    2015-08-01

    Full Text Available O objetivo desta revisão sistemática foi verificar a relação das concentrações de IL-6, TNF-α e MCP-1 em crianças com excesso de massa corporal. As bases de dados investigadas PUBMED, SciELO, LILACS e Periódico Capes foram consultadas retrospectivamente para os últimos seis anos (2009 a 2014 utilizando combinações de palavras chaves como inflamação, IL-6, TNF-α, MCP-1 combinadas com crianças e escolares. Foram analisados 21 artigos. Foi encontrado associação entre sobrepeso/obesidade com IL-6, TNF-α e MCP-1 em 73,3% (11/15, 80% (12/15 e 60% (3/5 dos estudos que analisaram tais marcadores, respectivamente. Crianças com excesso de massa corporal possuem concentrações elevadas de IL-6, TNF-α e MCP-1 resultando em inflamação sistêmica crônica e aumentando o risco de desenvolvimento de outras doenças cardiovasculares. 

  7. Relative contributions of decay accelerating factor (DAF), membrane cofactor protein (MCP) and CD59 in the protection of melanocytes from homologous complement

    NARCIS (Netherlands)

    Venneker, G. T.; Vodegel, R. M.; Okada, N.; Westerhof, W.; Bos, J. D.; Asghar, S. S.

    1998-01-01

    Complement regulatory molecules, membrane cofactor protein (MCP), decay accelerating factor (DAF) and CD59, protect body cells from autologous complement. They have wide tissue distribution but nothing is known about the expression of these molecules on human melanocytes. Since melanocytes are lysed

  8. Multiply Surface-Functionalized Nanoporous Carbon for Vehicular Hydrogen Storage

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifer, Peter [Univ. of Missouri, Columbia, MO (United States). Dept. of Physics; Gillespie, Andrew [Univ. of Missouri, Columbia, MO (United States). Dept. of Physics; Stalla, David [Univ. of Missouri, Columbia, MO (United States). Dept. of Physics; Dohnke, Elmar [Univ. of Missouri, Columbia, MO (United States). Dept. of Physics

    2017-02-20

    The purpose of the project “Multiply Surface-Functionalized Nanoporous Carbon for Vehicular Hydrogen Storage” is the development of materials that store hydrogen (H2) by adsorption in quantities and at conditions that outperform current compressed-gas H2 storage systems for electric power generation from hydrogen fuel cells (HFCs). Prominent areas of interest for HFCs are light-duty vehicles (“hydrogen cars”) and replacement of batteries with HFC systems in a wide spectrum of applications, ranging from forklifts to unmanned areal vehicles to portable power sources. State-of-the-art compressed H2 tanks operate at pressures between 350 and 700 bar at ambient temperature and store 3-4 percent of H2 by weight (wt%) and less than 25 grams of H2 per liter (g/L) of tank volume. Thus, the purpose of the project is to engineer adsorbents that achieve storage capacities better than compressed H2 at pressures less than 350 bar. Adsorption holds H2 molecules as a high-density film on the surface of a solid at low pressure, by virtue of attractive surface-gas interactions. At a given pressure, the density of the adsorbed film is the higher the stronger the binding of the molecules to the surface is (high binding energies). Thus, critical for high storage capacities are high surface areas, high binding energies, and low void fractions (high void fractions, such as in interstitial space between adsorbent particles, “waste” storage volume by holding hydrogen as non-adsorbed gas). Coexistence of high surface area and low void fraction makes the ideal adsorbent a nanoporous monolith, with pores wide enough to hold high-density hydrogen films, narrow enough to minimize storage as non-adsorbed gas, and thin walls between pores to minimize the volume occupied by solid instead of hydrogen. A monolith can be machined to fit into a rectangular tank (low pressure, conformable tank), cylindrical tank

  9. Cornell electron beam ion source

    International Nuclear Information System (INIS)

    Kostroun, V.O.; Ghanbari, E.; Beebe, E.N.; Janson, S.W.

    1981-01-01

    An electron beam ion source (EBIS) for the production of low energy, multiply charged ion beams to be used in atomic physics experiments has been designed and constructed. An external high perveance electron gun is used to launch the electron beam into a conventional solenoid. Novel features of the design include a distributed sputter ion pump to create the ultrahigh vacuum environment in the ionization region of the source and microprocessor control of the axial trap voltage supplies

  10. Neutron fluctuation analysis in a subcritical multiplying system with a stochastically pulsed poisson source

    International Nuclear Information System (INIS)

    Kostic, Lj.

    2003-01-01

    The influence of the stochastically pulsed Poisson source to the statistical properties of the subcritical multiplying system is analyzed in the paper. It is shown a strong dependence on the pulse period and pulse width of the source (author)

  11. Polarization of X rays of multiply charged ions in dense high-temperature plasma

    NARCIS (Netherlands)

    Baronova, EO; Dolgov, AN; Yakubovskii, LK

    2004-01-01

    The development of a method for studying the features of X-ray emission by multiply charged ions in a dense hot plasma is considered. These features are determined by the radiation polarization phenomenon.

  12. Karatsuba-Ofman Multiplier with Integrated Modular Reduction for GF(2m

    Directory of Open Access Journals (Sweden)

    CUEVAS-FARFAN, E.

    2013-05-01

    Full Text Available In this paper a novel GF(2m multiplier based on Karatsuba-Ofman Algorithm is presented. A binary field multiplication in polynomial basis is typically viewed as a two steps process, a polynomial multiplication followed by a modular reduction step. This research proposes a modification to the original Karatsuba-Ofman Algorithm in order to integrate the modular reduction inside the polynomial multiplication step. Modular reduction is achieved by using parallel linear feedback registers. The new algorithm is described in detail and results from a hardware implementation on FPGA technology are discussed. The hardware architecture is described in VHDL and synthesized for a Virtex-6 device. Although the proposed field multiplier can be implemented for arbitrary finite fields, the targeted finite fields are recommended for Elliptic Curve Cryptography. Comparing other KOA multipliers, our proposed multiplier uses 36% less area resources and improves the maximum delay in 10%.

  13. Comparison of the Effect of 1-MCP and Low-Pressure Air on Shelflife of Strawberry Fruit (Fragaria ananassa cv. Camarossa

    Directory of Open Access Journals (Sweden)

    B. Modares

    2013-10-01

    Full Text Available Strawberry (Fragaria×ananassa has tasteful, fragrant and nutritious fruits. But, because of delicate texture and high metabolic activities of the fruits at maturity, are very sensitive and easily decayed, and thus have short shelflife. Ethylene is one of the main causes of postharvest fruit losses, which could reduce the shelflife of strawberry. Therefore, an experiment was carried out to examine the effect of 1 µL/L 1-MCP treatment and low-pressure air pretreatment at 0.2 atm in 2 hours on apparent and physicochemical characteristics of strawberry fruit, cultivar Camarossa, during storage in cold store. The study was performed as split plots in time, based on complete randomized design with 3 replications. The results showed that the highest marketability (90%, fruit firmness (7.95 N, titrable organic acids (1.15 g/100 cc, vitamin C (78.13 mg/100 cc and total soluble solids (10.48 % and the lowest amount of apparent decay (13.3 %, acidity (3.63 and taste index (9.04 were obtained in 1-MCP and low-pressure air treatments, which shows the effect of treatments on reducing the rate of biochemical variations in fruit texture. Correlation coefficients between all treatments were significant (P≤0.01. Meanwhile, the positive effect of 1-MCP on appearance and studied physicochemical characteristics was more than low-pressure air pretreatment. Even, the combination of these two treatments had no significant difference with 1-MCp treatment alone. In general, this observation depicts the more positive and significant effect of 1-MCP treatment in delaying the maturity and improving the qualitative traits of strawberry fruits after being stored in cold storage.

  14. AOPPs Induce MCP-1 Expression by Increasing ROS-Mediated Activation of the NF-κB Pathway in Rat Mesangial Cells: Inhibition by Sesquiterpene Lactones

    Directory of Open Access Journals (Sweden)

    Jian-Cheng Wang

    2013-12-01

    Full Text Available Background: Monocyte chemoattractant protein-1 (MCP-1 plays an important role in extracellular matrix accumulation through macrophage recruitment and activation in the development and progression of diabetic nephropathy. Therefore, this study examined whether advanced oxidation protein products (AOPPs are involved in nuclear factor-κB (NF-κB activation and MCP-1 mRNA and protein expression in mesangial cells (MCs and evaluated the effects of derivatives of sesquiterpene lactones (SLs on AOPP-induced renal damage. Methods: MCP-1 mRNA and protein expression in MCs were determined by quantitative real-time PCR and ELISA, respectively. The level of intracellular reactive oxygen species (ROS was determined by flow cytometry. The protein expression of tubulin, P47, NF-κB p65, phospho-NF-κB p65, IκB, phospho-IκB, IKKß and phospho-IKKß was evaluated by Western blot. Results: AOPPs caused oxidative stress in MCs and activated the NF-κB pathway by inducing IκBa phosphorylation and degradation. Inhibition of ROS by SOD (ROS inhibitor blocked the AOPP-mediated NF-κB pathway. Moreover, the inhibition of AOPP-induced overproduction of MCP-1 mRNA and protein was associated with inhibition of IκBa degradation by SLs. Conclusion: AOPPs induce MCP-1 expression by activating the ROS/NF-κB pathway and can be inhibited by SLs. These findings may provide a novel approach to treat inflammatory and immune renal diseases, including diabetic nephropathy.

  15. Beyond the static money multiplier: in search of a dynamic theory of money

    OpenAIRE

    Berardi, Michele

    2007-01-01

    In this paper, we analyze the process of money creation in a credit economy. We start from the consideration that the traditional money multiplier is a poor description of this process and present an alternative and dynamic approach that takes into account the heterogeneity of agents in the economy and their interactions. We show that this heterogeneity can account for the instability of the multiplier and that it can make the system path-dependent. By using concepts and techniques borrowed f...

  16. Atlantic Richfield Hanford Company californium multiplier/delayed neutron counter safety analysis

    International Nuclear Information System (INIS)

    Zimmer, W.H.

    1976-08-01

    The Californium Multiplier (CFX) is a subcritical assembly of uranium surrounding 252 Cf spontaneously fissioning neutron sources; its function is to multiply the neutron flux to a level useful for activation analysis. This document summarizes the safety analysis aspects of the CFX, DNC, pneumatic transfer system, and instrumentation and to detail all the aspects of the total facility as a starting point for the ARHCO Safety Analysis Review. Recognized hazards and steps already taken to neutralize them are itemized

  17. Solution of second order linear fuzzy difference equation by Lagrange's multiplier method

    Directory of Open Access Journals (Sweden)

    Sankar Prasad Mondal

    2016-06-01

    Full Text Available In this paper we execute the solution procedure for second order linear fuzzy difference equation by Lagrange's multiplier method. In crisp sense the difference equation are easy to solve, but when we take in fuzzy sense it forms a system of difference equation which is not so easy to solve. By the help of Lagrange's multiplier we can solved it easily. The results are illustrated by two different numerical examples and followed by two applications.

  18. SIMAC - A phosphoproteomic strategy for the rapid separation of mono-phosphorylated from multiply phosphorylated peptides

    DEFF Research Database (Denmark)

    Thingholm, Tine E; Jensen, Ole N; Robinson, Phillip J

    2008-01-01

    spectrometric analysis, such as immobilized metal affinity chromatography or titanium dioxide the coverage of the phosphoproteome of a given sample is limited. Here we report a simple and rapid strategy - SIMAC - for sequential separation of mono-phosphorylated peptides and multiply phosphorylated peptides from...... and an optimized titanium dioxide chromatographic method. More than double the total number of identified phosphorylation sites was obtained with SIMAC, primarily from a three-fold increase in recovery of multiply phosphorylated peptides....

  19. Human reliability under sleep deprivation: Derivation of performance shaping factor multipliers from empirical data

    International Nuclear Information System (INIS)

    Griffith, Candice D.; Mahadevan, Sankaran

    2015-01-01

    This paper develops a probabilistic approach that could use empirical data to derive values of performance shaping factor (PSF) multipliers for use in quantitative human reliability analysis (HRA). The proposed approach is illustrated with data on sleep deprivation effects on performance. A review of existing HRA methods reveals that sleep deprivation is not explicitly included at present, and expert opinion is frequently used to inform HRA model multipliers. In this paper, quantitative data from empirical studies regarding the effect of continuous hours of wakefulness on performance measures (reaction time, accuracy, and number of lapses) are used to develop a method to derive PSF multiplier values for sleep deprivation, in the context of the SPAR-H model. Data is extracted from the identified studies according to the meta-analysis research synthesis method and used to investigate performance trends and error probabilities. The error probabilities in test and control conditions are compared, and the resulting probability ratios are suggested for use in informing the selection of PSF multipliers in HRA methods. Although illustrated for sleep deprivation, the proposed methodology is general, and can be applied to other performance shaping factors. - Highlights: • Method proposed to derive performance shaping factor multipliers from empirical data. • Studies reporting the effect of sleep deprivation on performance are analyzed. • Test data using psychomotor vigilance tasks are analyzed. • Error probability multipliers computed for reaction time, lapses, and accuracy measures.

  20. Experimental and theoretical studies of the energy level structure of multiply charged many-electron ions

    International Nuclear Information System (INIS)

    Redfors, A.

    1991-01-01

    Magnesiumlike and aluminumlike spectra of the elements calcium - germanium have been obtained through the use of laser-produced plasmas (LPP) and a 3 m normal incidence vacuum spectrograph. The spectral analyses were mainly based on isoelectronic regularities. Intermediate ionization stages of cerium (Ce V) and silicon (SI VI) have also been studied. The light sources in these cases were a sliding spark and a modified version of the LPP. The Eagle spectrograph at the National Institute of Standards and Technology, Gaitherburg, Maryland was used to record the cerium spectrum. Ab initio calculations and least-squares fits of the Slater energy parameters to the experimental energy levels are reported for all investigated spectra. Theoretical predictions of oscillator strengths for Y III and Zr III in the region 1150-3200 AA are presented. The oscillator strengths are needed for abundance determinations of Y 2+ and Zr 2+ in chemically peculiar stars, Cp stars. (65 refs.)

  1. Study of the characteristics of gas electron multipliers for the FAIR experiment CBM

    International Nuclear Information System (INIS)

    Biswas, S.; Abuhoza, A.; Frankenfeld, U.; Hehner, J.; Schmidt, C.J.; Traeger, M.; Schmidt, H.R.; Colafranceschi, S.; Marinov, A.; Sharma, A.

    2011-01-01

    The Compressed Baryonic Matter (CBM) experiment at the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany will use proton and heavy ion beams to study matter at extreme conditions. The CBM experiment at FAIR is designed to explore the QCD phase diagram in the region of high baryon densities. With CBM we will enter a new era of nuclear matter research by measuring rare diagnostic probes never observed before at FAIR energies, and thus CBM has a unique discovery potential. This will only be possible with the application of advanced instrumentation, including highly segmented and fast gaseous detectors

  2. Testing of Track Point Resolution of Gas Electron Multiplier with Pion Beam at CERN SPS

    CERN Document Server

    Adak, R P; Das, S; Dubey, A K; Ganti, M S; Saini, J; Singaraju, R

    2015-01-01

    A muon detection system using segmented and instrumented absorber has been designed for high-energy heavy-ion collision experiments to be held at GSI, Darmstadt, Germany. The muon detector system is mounted downstream of a Silicon Tracking System. The reconstructed tracks from the STS are to be matched to the hits in the GEM detector. For reconstructing track in the GEM Detector, track point resolution is an important issue. We report her first time the track point resolution of the GEM detector.

  3. Theoretical lifetimes and fluorescence yields for multiply-ionized fluorine

    International Nuclear Information System (INIS)

    Tunnell, T.W.; Can, C.; Bhalla, C.P.

    1978-01-01

    Theoretical lifetimes and multiplet partial fluorescence yields for various fluorine ions with a single K-shell vacancy were calculated. For few-electron systems, the lifetimes and line fluorescence yields were computed in the intermediate coupling scheme with the inclusion of the effects arising from configuration interactions. 6 references

  4. Selective Dirac voltage engineering of individual graphene field-effect transistors for digital inverter and frequency multiplier integrations.

    Science.gov (United States)

    Sul, Onejae; Kim, Kyumin; Jung, Yungwoo; Choi, Eunsuk; Lee, Seung-Beck

    2017-09-15

    The ambipolar band structure of graphene presents unique opportunities for novel electronic device applications. A cycle of gate voltage sweep in a conventional graphene transistor produces a frequency-doubled output current. To increase the frequency further, we used various graphene doping control techniques to produce Dirac voltage engineered graphene channels. The various surface treatments and substrate conditions produced differently doped graphene channels that were integrated on a single substrate and multiple Dirac voltages were observed by applying a single gate voltage sweep. We applied the Dirac voltage engineering techniques to graphene field-effect transistors on a single chip for the fabrication of a frequency multiplier and a logic inverter demonstrating analog and digital circuit application possibilities.

  5. Selective Dirac voltage engineering of individual graphene field-effect transistors for digital inverter and frequency multiplier integrations

    Science.gov (United States)

    Sul, Onejae; Kim, Kyumin; Jung, Yungwoo; Choi, Eunsuk; Lee, Seung-Beck

    2017-09-01

    The ambipolar band structure of graphene presents unique opportunities for novel electronic device applications. A cycle of gate voltage sweep in a conventional graphene transistor produces a frequency-doubled output current. To increase the frequency further, we used various graphene doping control techniques to produce Dirac voltage engineered graphene channels. The various surface treatments and substrate conditions produced differently doped graphene channels that were integrated on a single substrate and multiple Dirac voltages were observed by applying a single gate voltage sweep. We applied the Dirac voltage engineering techniques to graphene field-effect transistors on a single chip for the fabrication of a frequency multiplier and a logic inverter demonstrating analog and digital circuit application possibilities.

  6. Conservação pós-colheita de melão Charentais tratado com 1-MCP e armazenado sob refrigeração e atmosfera modificada Postharvest conservation of charentais melons treated with 1-MCP and stored under refrigeration and modified atmosphere

    Directory of Open Access Journals (Sweden)

    Pahlevi A de Souza

    2008-12-01

    Full Text Available Objetivando avaliar a vida útil pós-colheita de melão tipo Charentais (Cucumis melo L. sob refrigeração, tratados com 1-MCP e associado ou não a atmosfera modificada (AM, foram conduzidos dois experimentos em laboratório da Embrapa Agroindústria Tropical, Fortaleza-CE. Os frutos foram provenientes da Agroindústria Nolem Comercial Importadora e Exportadora Ltda, localizada no Agropólo Mossoró Açu-RN. Os frutos foram tratados com 300 e 600 ppb de 1-MCP, em seguida, metade desses frutos foram embalados em filmes plásticos, mantendo-se frutos embalados sem aplicação de 1-MCP nas mesmas condições de armazenamento dos demais. Os melões foram armazenados por 21 dias sendo 14 dias (9±1ºC e 87±5% UR + 7 dias (22±2ºC e 70±5% UR. Em função da aparência externa, a vida útil pós-colheita dos frutos armazenados sob atmosfera modificada, com ou sem tratamento inicial de 1-MCP foi de 21 dias, enquanto que dos frutos tratados inicialmente apenas com 1-MCP foi de 19 dias. A aplicação do 1-MCP proporcionou redução na atividade respiratória e na produção de etileno, e maior retenção da firmeza da polpa, menor perda de massa e melhor aparência externa quando associado a atmosfera modificada. A atmosfera modificada, isoladamente, foi eficiente em reduzir a perda de massa e manter melhor aparência externa.Aiming to evaluate the postharvest shelf life of Charentais melon (Cucumis melo L. stored under refrigeration, the fruits were treated with 1-MCP, associated or not with modified atmosphere (MAP. Two experiments were carried out at the laboratory of Embrapa Agroindústria Tropical in Fortaleza, Brazil, analyzing the chemical and physic quality characteristics. The fruits were obtained at the Agroindústria Nolem Comercial Importadora e Exportadora Ltda, located in Mossoró Açu, Brazil. The fruits were treated with 300 and 600 nL L-1 of 1-MCP, half of those were wrapped in plastic films, which were wrapped without the use of 1

  7. EFECTO DEL 1-METILCICLOPROPENO (1-MCP Y TRATAMIENTO HIDROTÉRMICO SOBRE LA FISIOLOGÍA Y CALIDAD DEL MANGO 'KEITT'

    Directory of Open Access Journals (Sweden)

    J. A. Osuna-García

    2007-01-01

    Full Text Available El objetivo del presente trabajo fue evaluar el efecto del 1-MCP (0 y 300 nl·litro-1 y diferentes niveles de tratamiento hidrotérmico (0, 52 °C por 5 min y 46 °C por 110 min sobre la fisiología y calidad de mango 'Keitt'. Se analizó velocidad de respiración, pérdida de peso, firmeza, color de pulpa, sólidos solubles totales y porcentaje de frutos enfermos. Se encontró que la efectividad del 1-MCP varió acorde al nivel de tratamiento hidrotérmico. En frutos sin hidrotérmico el 1-MCP disminuyó velocidad de respiración, no influyó en la pérdida de peso, mantuvo cuatro veces más la firmeza y retrasó el cambio de color de pulpa y el aumento de los sólidos solubles. Sin embargo, bajo tratamiento hidrotérmico por 5 min el 1-MCP incrementó velocidad de respiración, no influyó en la pérdida de peso, mantuvo dos veces más la firmeza de pulpa, retrasó el desarrollo del color de pulpa y mantuvo sin cambios los sólidos solubles. La efectividad del 1-MCP sobre firmeza y pérdida de peso fue significativamente afectada por el tratamiento hidrotérmico de 110 min, y no tuvo ningún efecto sobre el control de enfermedades, sin embargo, el tratamiento con agua caliente por 5 min redujo en más de 50 % la presencia de frutos enfermos. El 1-MCP en combinación con el tratamiento hidrotérmico de 5 min alargó en cinco días la vida de anaquel de los frutos y podría ser una alternativa viable en mercados que no requieren tratamiento hidrotérmico cuarentenario para el control de mosca de la fruta.

  8. p115 RhoGEF activates the Rac1 GTPase signaling cascade in MCP1 chemokine-induced vascular smooth muscle cell migration and proliferation.

    Science.gov (United States)

    Singh, Nikhlesh K; Janjanam, Jagadeesh; Rao, Gadiparthi N

    2017-08-25

    Although the involvement of Rho proteins in the pathogenesis of vascular diseases is well studied, little is known about the role of their upstream regulators, the Rho guanine nucleotide exchange factors (RhoGEFs). Here, we sought to identify the RhoGEFs involved in monocyte chemotactic protein 1 (MCP1)-induced vascular wall remodeling. We found that, among the RhoGEFs tested, MCP1 induced tyrosine phosphorylation of p115 RhoGEF but not of PDZ RhoGEF or leukemia-associated RhoGEF in human aortic smooth muscle cells (HASMCs). Moreover, p115 RhoGEF inhibition suppressed MCP1-induced HASMC migration and proliferation. Consistent with these observations, balloon injury (BI) induced p115 RhoGEF tyrosine phosphorylation in rat common carotid arteries, and siRNA-mediated down-regulation of its levels substantially attenuated BI-induced smooth muscle cell migration and proliferation, resulting in reduced neointima formation. Furthermore, depletion of p115 RhoGEF levels also abrogated MCP1- or BI-induced Rac1-NFATc1-cyclin D1-CDK6-PKN1-CDK4-PAK1 signaling, which, as we reported previously, is involved in vascular wall remodeling. Our findings also show that protein kinase N1 (PKN1) downstream of Rac1-cyclin D1/CDK6 and upstream of CDK4-PAK1 in the p115 RhoGEF-Rac1-NFATc1-cyclin D1-CDK6-PKN1-CDK4-PAK1 signaling axis is involved in the modulation of vascular wall remodeling. Of note, we also observed that CCR2-G i/o -Fyn signaling mediates MCP1-induced p115 RhoGEF and Rac1 GTPase activation. These findings suggest that p115 RhoGEF is critical for MCP1-induced HASMC migration and proliferation in vitro and for injury-induced neointima formation in vivo by modulating Rac1-NFATc1-cyclin D1-CDK6-PKN1-CDK4-PAK1 signaling. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  9. Cigarette smoke-related hydroquinone dysregulates MCP-1, VEGF and PEDF expression in retinal pigment epithelium in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Marianne Pons

    2011-02-01

    Full Text Available Age-related macular degeneration (AMD is the leading cause of legal blindness in the elderly population. Debris (termed drusen below the retinal pigment epithelium (RPE have been recognized as a risk factor for dry AMD and its progression to wet AMD, which is characterized by choroidal neovascularization (CNV. The underlying mechanism of how drusen might elicit CNV remains undefined. Cigarette smoking, oxidative damage to the RPE and inflammation are postulated to be involved in the pathophysiology of the disease. To better understand the cellular mechanism(s linking oxidative stress and inflammation to AMD, we examined the expression of pro-inflammatory monocyte chemoattractant protein-1 (MCP-1, pro-angiogenic vascular endothelial growth factor (VEGF and anti-angiogenic pigment epithelial derived factor (PEDF in RPE from smoker patients with AMD. We also evaluated the effects of hydroquinone (HQ, a major pro-oxidant in cigarette smoke on MCP-1, VEGF and PEDF expression in cultured ARPE-19 cells and RPE/choroids from C57BL/6 mice.MCP-1, VEGF and PEDF expression was examined by real-time PCR, Western blot, and ELISA. Low levels of MCP-1 protein were detected in RPE from AMD smoker patients relative to controls. Both MCP-1 mRNA and protein were downregulated in ARPE-19 cells and RPE/choroids from C57BL/6 mice after 5 days and 3 weeks of exposure to HQ-induced oxidative injury. VEGF protein expression was increased and PEDF protein expression was decreased in RPE from smoker patients with AMD versus controls resulting in increased VEGF/PEDF ratio. Treatment with HQ for 5 days and 3 weeks increased the VEGF/PEDF ratio in vitro and in vivo.We propose that impaired RPE-derived MCP-1-mediated scavenging macrophages recruitment and phagocytosis might lead to incomplete clearance of proinflammatory debris and infiltration of proangiogenic macrophages which along with increased VEGF/PEDF ratio favoring angiogenesis might promote drusen accumulation and

  10. Determination of stress multipliers for thin perforated plates with square array of holes

    International Nuclear Information System (INIS)

    Bhattacharya, A.; Murli, B.; Kushwaha, H.S.

    1991-01-01

    The peak stress multipliers are required to determine the maximum stresses in perforated plates for the realistic evaluation of their fatigue life. The Section III of ASME Boiler and Pressure Vessels Code does not provide any information about such multipliers to be used in thin perforated plates with square penetration pattern. Although such multipliers for membrane loadings are available in literature, they were obtained either by classical analysis or by photoelastic experiments and there is no significant finite element analysis in this area. Also it has been a common practice among designers to apply the same multipliers for loads producing bending type of stress. The stress multipliers in bending are lower than those in membrane. Therefore a reduction of resultant peak stress occurs if proper stress multipliers are used for bending. The present paper is aimed at developing a finite element technique which can be used for determining the peak stress multipliers in thin plates for membrane as well as bending loads. A quarter symmetric part of a 3 x 3 square array was chosen for the analysis. The results were obtained by computer programs PAFEC and COSMOS/M using 2-D plane stress elements for the membrane and degenerated 3-D shell element for the bending part. The results for the membrane are compared with Bailey, Hicks and Hulbert and with Meijers' finite element results for the bending part. A study was made at the initial stage by analysing a 6 x 6 square array to see the effect of holes beyond one pitch, which were left out by the 3 x 3 array and the effect of additional holes was found to be negligible. Therefore it was decided to carry out further analysis with 3 x 3 square array. Photoelastic experiments were also performed to validate the results obtained by theoretical analysis. (author)

  11. A case-control association study between Obsessive-Compulsive Disorder (OCD and the MCP-1 -2518G/A polymorphism in a Chinese sample Estudo de associação de casos-controle entre Transtorno Obsessivo-Compulsivo (TOC e polimorfismo MCP-1 -2518G/A em uma coorte chinesa

    Directory of Open Access Journals (Sweden)

    Xinhua Zhang

    2012-12-01

    Full Text Available OBJECTIVE: To investigate the association between Obsessive-Compulsive Disorder (OCD and a functional polymorphism of MCP-1 in the Chinese Han population. METHOD: We genotyped and performed a case-control association analysis of the MCP-1 -2518G/A polymorphism in 200 OCD patients and 294 healthy control subjects. RESULTS: There was no significant difference in MCP-1 -2518G/A genotypic and allelic frequencies between OCD cases and controls (x² = 1.123, df = 2, P = 0.57 by genotype; x² = 0.802, df = 1, P = 0.37 by allele. CONCLUSIONS: Our results indicated that MCP-1 -2518G/A may not play a major role in the genetic predisposition of the Chinese Han population to OCD. However, further studies using a larger number of subjects are required to obtain a clear conclusion.OBJETIVO: Investigar a relação entre Transtorno Obsessivo-Compusilvo (TOC e um polimorfismo funcional de MCP-1 na população chinesa de etnia Han. MÉTODOS: Determinamos os genótipos e realizamos uma análise de associações de casos-controle de polimorfismo MCP-1 -2518G/A em 200 indivíduos com TOC e 294 indivíduos saudáveis (controle. RESULTADOS: Não houve diferença significativa no genótipo MCP-1 -2518G/A e nas frequências alélicas entre casos de TOC e controles (x² = 1,123, df = 2, P = 0,57 por genotipo; x² = 0,802, df = 1, P = 0,37 por alelo. CONCLUSÕES: Nossos resultados indicaram que MCP-1 -2518G/A pode não ter grande participação na predisposição genética da etnia Han no que diz respeito ao TOC. Contudo, novos estudos com um maior número de indivíduos são necessários para uma conclusão mais clara.

  12. Electronic stopping in ion-fullerene collisions

    NARCIS (Netherlands)

    Schlathölter, T.A.; Hadjar, O.; Hoekstra, R.A.; Morgenstern, R.W.H.

    The electronic friction experienced by a multiply charged ion interacting with the valence electrons of a single fullerene is an important aspect of the collision dynamics. It manifests itself in a considerable loss of projectile kinetic energy transferred to the target, resulting in excitation. The

  13. Effects of collisions on level populations and dielectronic recombination rates of multiply charged ions

    International Nuclear Information System (INIS)

    Jacobs, V.L.; Davis, J.

    1978-01-01

    A generalization of previously reported statistical theories is developed for determining the excited-level populations and the ionization-recombination balance of multiply charged atomic ions in an optically thin high-temperature plasma. Account is taken of the most important collisional and radiative processes involving bound and autoionizing levels in three consecutive ionization stages. We obtain a set of rate equations for the population densities of the low-lying levels which contains effective excitation, ionization, and recombination rates describing indirect transitions through the more highly excited bound and autoionizing levels. The familiar corona-model equations for the ground-state populations are recovered by making the assumption that all excited states decay by only spontaneous radiative or autoionization processes. When collisional processes become efficient in depopulating the highly excited levels important in dielectronic recombination, the effective rate of recombination must be described by a collisional-dielectronic recombination coefficient. Results of calculations are presented for the collisional-dielectronic recombination rate coefficients for recombination of Fe +8 --Fe +13 ions. At an electron density of 10 16 cm -3 , dielectronic recombination is still the dominant recombination process. However, the collisional-dielectronic recombination rate coefficients are found to be reduced by about an order of magnitude from their corona-model values due to the effects of multiple-collisional excitations on the populations of the highly excited bound levels of the recombined ion. The dielectronic recombination rates into these highly excited levels are found to be enhanced by the effects of collisionally induced angular momentum redistribution on the populations of the autoionizing levels

  14. Lagrangian relaxation technique in power systems operation planning: Multipliers updating problem

    Energy Technology Data Exchange (ETDEWEB)

    Ruzic, S. [Electric Power Utility of Serbia, Belgrade (Yugoslavia)

    1995-11-01

    All Lagrangian relaxation based approaches to the power systems operation planning have an important common part: the Lagrangian multipliers correction procedure. It is the subject of this paper. Different approaches presented in the literature are discussed and an original method for the Lagrangian multipliers updating is proposed. The basic idea of this new method is to update Lagrangian multipliers trying to satisfy Khun-Tucker optimality conditions. Instead of the dual function maximization the `distance of optimality function` is defined and minimized. If Khun-Tucker optimality conditions are satisfied the value of this function is in range (-1,0); otherwise the function has a big positive value. This method called `the distance of optimality method` takes into account future changes in planning generations due to the Lagrangian multipliers updating. The influence of changes in a multiplier associated to one system constraint to the satisfaction of some other system requirements is also considered. The numerical efficiency of the proposed method is analyzed and compared with results obtained using the sub-gradient technique. 20 refs, 2 tabs

  15. Dissociation of multiply charged ICN by Coulomb explosion

    Energy Technology Data Exchange (ETDEWEB)

    Eland, J. H. D. [Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ (United Kingdom); Department of Physics, University of Gothenburg, Origovägen 6B, SE-412 96 Gothenburg (Sweden); Singh, R.; Hult Roos, A.; Andersson, J.; Squibb, R. J.; Feifel, R. [Department of Physics, University of Gothenburg, Origovägen 6B, SE-412 96 Gothenburg (Sweden); Pickering, J. D.; Brouard, M. [Department of Chemistry, The Chemistry Research Laboratory, Oxford University, Mansfield Road, Oxford OX1 3TA (United Kingdom); Slater, C. S. [Department of Physics, University of Gothenburg, Origovägen 6B, SE-412 96 Gothenburg (Sweden); Department of Chemistry, The Chemistry Research Laboratory, Oxford University, Mansfield Road, Oxford OX1 3TA (United Kingdom); Zagorodskikh, S. [Department of Physics, University of Gothenburg, Origovägen 6B, SE-412 96 Gothenburg (Sweden); Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala (Sweden)

    2016-08-21

    The fragmentations of iodine cyanide ions created with 2 to 8 positive charges by photoionization from inner shells with binding energies from 59 eV (I 4d) to ca. 900 eV (I 3p) have been examined by multi-electron and multi-ion coincidence spectroscopy with velocity map imaging ion capability. The charge distributions produced by hole formation in each shell are characterised and systematic effects of the number of charges and of initial charge localisation are found.

  16. Object-Relational Management of Multiply Represented Geographic Entities

    DEFF Research Database (Denmark)

    Friis-Christensen, Anders; Jensen, Christian Søndergaard

    2003-01-01

    Multiple representation occurs when information about the same geographic entity is represented electronically more than once. This occurs frequently in practice, and it invariably results in the occurrence of inconsistencies among the different representations. We propose to resolve this situation...... by introducing a multiple representation management system (MRMS), the schema of which includes rules that specify how to identify representations of the same entity, rules that specify consistency requirements, and rules used to restore consistency when necessary. In this paper, we demonstrate by means...

  17. Status and problems of multiply ionized atom spectroscopy

    International Nuclear Information System (INIS)

    Kononov, Eh.Ya.; Ryabtsev, A.N.

    1984-01-01

    Principal directions of investigations associated with identification of spectral lines and with determination of energy structure of high multiplicity ions are analyzed. The considered part of atomic spectroscopy is developed both in the direction of obtaining high multiplicity ion spectra and interpretation of spectral details associated with excitation conditions and in the direction of detailed study on compound energy structures of electron shells. Spectroscopy with fast ion beams is widely developed. Accumulated atomic data, developed methods of atomic calculations and improvement of observation technique permit to realize complex spectroscopic diagnostics in astrophysics and hot plasma physics

  18. Measurement of 2-5 keV x-ray emission from laser-target interactions by using fluor-MCP and CsI-XRD detectors

    International Nuclear Information System (INIS)

    Lee, P.H.Y.; Tirsell, K.G.; Leipelt, G.R.; Laird, W.B.

    1981-01-01

    For inertial confinement fusion plasma diagnostics, x-ray diode (XRD) detectors using conventional cathodes are not sensitive enough to measure x-rays above approx. 1.5 keV. However, for laser driver fusion targets, x-rays in the range of 2 to 5 keV are important because of their mobility in the target. We have successfully used fluor-microchannel plate (MCP) detectors to obtain absolute x-ray measurements in the 2 to 5 keV range. Recent data obtained from experiments on the Shiva laser system are presented. In addition, designs for a variety of channels in the range using fluor-MCP and CsI-XRD's above 1.5 keV will be discussed

  19. Influence of promoting blood circulation to remove blood stasis combined with laparoscopy on serum MCP-1, RANTES, oxidative stress and hormones in infertile patients with endometriosis

    Directory of Open Access Journals (Sweden)

    Xiao-Sha Zhang

    2017-11-01

    Full Text Available Objective: To observe the influence of promoting blood circulation to remove blood stasis combined with laparoscopy on serum MCP-1, RANTES, oxidative stress and hormones in infertile patients with endometriosis. Methods: A total of 60 infertile patients with endometriosis were randomly divided into observation group (30 cases and control group (30 cases. Observation group: promoting blood circulation to remove blood stasis combined with laparoscopy; control group: patients were treated only by laparoscopy. Recording and comparing the levels of MCP-1, RANTES, oxidative stress and hormones before and after treatment. Results: (1 Before treatment, there was no statistically significant difference in the serum MCP-1, RANTES, AOPP, MDA, SOD, levels between the two groups. After treatment, compared with the same group before treatment, the serum RANTES, AOPP, MDA levels of the two groups were significantly lower, the serum SOD level of the two groups were significantly higher, and those levels of observation group were significantly better than the control group, there was significant difference between the two groups. (2 Before treatment, there was no statistically significant difference in the serum FSH, LH, E2, P, PRL levels between the two groups. After treatment, compared with the same group before treatment, the serum FSH, LH, P, PRL levels of the two groups were significantly higher, the serum E2 level of the two groups were significantly lower, and those levels of observation group were significantly better than the control group, there was significant difference between the two groups. Conclusion: Promoting blood circulation to remove blood stasis combined with laparoscopy for infertile patients with endometriosis can reduce the levels of serum MCP-1, RANTES, oxidative stress, hormones and be beneficial to protect their uterine function.

  20. The host response to the probiotic Escherichia coli strain Nissle 1917: Specific up-regulation of the proinflammatory chemokine MCP-1

    Directory of Open Access Journals (Sweden)

    Ukena Sya N

    2005-12-01

    Full Text Available Abstract Background The use of live microorganisms to influence positively the course of intestinal disorders such as infectious diarrhea or chronic inflammatory conditions has recently gained increasing interest as a therapeutic alternative. In vitro and in vivo investigations have demonstrated that probiotic-host eukaryotic cell interactions evoke a large number of responses potentially responsible for the effects of probiotics. The aim of this study was to improve our understanding of the E. coli Nissle 1917-host interaction by analyzing the gene expression pattern initiated by this probiotic in human intestinal epithelial cells. Methods Gene expression profiles of Caco-2 cells treated with E. coli Nissle 1917 were analyzed with microarrays. A second human intestinal cell line and also pieces of small intestine from BALB/c mice were used to confirm regulatory data of selected genes by real-time RT-PCR and cytometric bead array (CBA to detect secretion of corresponding proteins. Results Whole genome expression analysis revealed 126 genes specifically regulated after treatment of confluent Caco-2 cells with E. coli Nissle 1917. Among others, expression of genes encoding the proinflammatory molecules monocyte chemoattractant protein-1 ligand 2 (MCP-1, macrophage inflammatory protein-2 alpha (MIP-2α and macrophage inflammatory protein-2 beta (MIP-2β was increased up to 10 fold. Caco-2 cells cocultured with E. coli Nissle 1917 also secreted high amounts of MCP-1 protein. Elevated levels of MCP-1 and MIP-2α mRNA could be confirmed with Lovo cells. MCP-1 gene expression was also up-regulated in mouse intestinal tissue. Conclusion Thus, probiotic E. coli Nissle 1917 specifically upregulates expression of proinflammatory genes and proteins in human and mouse intestinal epithelial cells.

  1. Analysis of the temporal expression of chemokines and chemokine receptors during experimental granulomatous inflammation: role and expression of MIP-1α and MCP-1

    Science.gov (United States)

    Carollo, Maria; Hogaboam, Cory M; Kunkel, Stephen L; Delaney, Stephen; Christie, Mark I; Perretti, Mauro

    2001-01-01

    Chemokine expression and function was monitored in an experimental model of granulomatous tissue formation after injection of croton oil in complete Freund's adjuvant (CO/CFA) into mouse dorsal air-pouches up to 28 days. In the first week, mast cell degranulation and leukocyte influx (mononuclear cell, MNC, and polymorphonuclear cell, PMN) were associated with CXCR2, KC and macrophage inflammatory protein (MIP)-2 mRNA expression, as determined by TaqMan® reverse transcriptase-polymerase chain reaction. KC (∼400 pg mg protein−1, n=12) and MIP-2 (∼800 pg mg protein−1, n=12) proteins peaked at day 7, together with myeloperoxidase (MPO) activity. Highest MIP-1α (>1 ng mg protein−1, n=12) levels were measured at day 3. After day 7, a gradual increase in CCR2 and CCR5 mRNA, monocyte chemoattractant protein (MCP)-1 mRNA and protein expression was measured. MCP-1 protein peaked at day 21 (∼150 pg mg protein−1, n=12) and was predominantly expressed by mast cells. A gradual increase in N-acetyl-β-D-glucosaminidase (NAG) activity (maximal at 28 days) was also measured. An antiserum against MIP-1α did not modify the inflammatory response measured at day 7 (except for a 50% reduction in MIP-1α levels), but provoked a significant increase in MPO, NAG and MCP-1 levels as measured at day 21 (n=6, Pvalues (n=8, P<0.05). In conclusion, we have shown that CO/CFA initiates a complex inflammatory reaction in which initial expression of MIP-1α serves a protective role whereas delayed expression of MCP-1 seems to have a genuine pro-inflammatory role. PMID:11704636

  2. Hardware Design and Implementation of Fixed-Width Standard and Truncated 4×4, 6×6, 8×8 and 12×12-BIT Multipliers Using Fpga

    Science.gov (United States)

    Rais, Muhammad H.

    2010-06-01

    This paper presents Field Programmable Gate Array (FPGA) implementation of standard and truncated multipliers using Very High Speed Integrated Circuit Hardware Description Language (VHDL). Truncated multiplier is a good candidate for digital signal processing (DSP) applications such as finite impulse response (FIR) and discrete cosine transform (DCT). Remarkable reduction in FPGA resources, delay, and power can be achieved using truncated multipliers instead of standard parallel multipliers when the full precision of the standard multiplier is not required. The truncated multipliers show significant improvement as compared to standard multipliers. Results show that the anomaly in Spartan-3 AN average connection and maximum pin delay have been efficiently reduced in Virtex-4 device.

  3. Folic Acid Supplementation Delays Atherosclerotic Lesion Development by Modulating MCP1 and VEGF DNA Methylation Levels In Vivo and In Vitro

    Science.gov (United States)

    Cui, Shanshan; Li, Wen; Lv, Xin; Wang, Pengyan; Gao, Yuxia; Huang, Guowei

    2017-01-01

    The pathogenesis of atherosclerosis has been partly acknowledged to result from aberrant epigenetic mechanisms. Accordingly, low folate levels are considered to be a contributing factor to promoting vascular disease because of deregulation of DNA methylation. We hypothesized that increasing the levels of folic acid may act via an epigenetic gene silencing mechanism to ameliorate atherosclerosis. Here, we investigated the atheroprotective effects of folic acid and the resultant methylation status in high-fat diet-fed ApoE knockout mice and in oxidized low-density lipoprotein-treated human umbilical vein endothelial cells. We analyzed atherosclerotic lesion histology, folate concentration, homocysteine concentration, S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH), and DNA methyltransferase activity, as well as monocyte chemotactic protein-1 (MCP1) and vascular endothelial growth factor (VEGF) expression and promoter methylation. Folic acid reduced atherosclerotic lesion size in ApoE knockout mice. The underlying folic acid protective mechanism appears to operate through regulating the normal homocysteine state, upregulating the SAM: SAH ratio, elevating DNA methyltransferase activity and expression, altering MCP1 and VEGF promoter methylation, and inhibiting MCP1 and VEGF expression. We conclude that folic acid supplementation effectively prevented atherosclerosis by modifying DNA methylation through the methionine cycle, improving DNA methyltransferase activity and expression, and thus changing the expression of atherosclerosis-related genes. PMID:28475147

  4. Rhizoma coptidis Inhibits LPS-Induced MCP-1/CCL2 Production in Murine Macrophages via an AP-1 and NFB-Dependent Pathway

    Directory of Open Access Journals (Sweden)

    Andrew Remppis

    2010-01-01

    Full Text Available Introduction. The Chinese extract Rhizoma coptidis is well known for its anti-inflammatory, antioxidative, antiviral, and antimicrobial activity. The exact mechanisms of action are not fully understood. Methods. We examined the effect of the extract and its main compound, berberine, on LPS-induced inflammatory activity in a murine macrophage cell line. RAW 264.7 cells were stimulated with LPS and incubated with either Rhizoma coptidis extract or berberine. Activation of AP-1 and NFB was analyzed in nuclear extracts, secretion of MCP-1/CCL2 was measured in supernatants. Results. Incubation with Rhizoma coptidis and berberine strongly inhibited LPS-induced monocyte chemoattractant protein (MCP-1 production in RAW cells. Activation of the transcription factors AP-1 and NFB was inhibited by Rhizoma coptidis in a dose- and time-dependent fashion. Conclusions. Rhizoma coptidis extract inhibits LPS-induced MCP-1/CCL2 production in vitro via an AP-1 and NFB-dependent pathway. Anti-inflammatory action of the extract is mediated mainly by its alkaloid compound berberine.

  5. Rhizoma Coptidis Inhibits LPS-Induced MCP-1/CCL2 Production in Murine Macrophages via an AP-1 and NFκB-Dependent Pathway

    Science.gov (United States)

    Remppis, Andrew; Bea, Florian; Greten, Henry Johannes; Buttler, Annette; Wang, Hongjie; Zhou, Qianxing; Preusch, Michael R.; Enk, Ronny; Ehehalt, Robert; Katus, Hugo; Blessing, Erwin

    2010-01-01

    Introduction. The Chinese extract Rhizoma coptidis is well known for its anti-inflammatory, antioxidative, antiviral, and antimicrobial activity. The exact mechanisms of action are not fully understood. Methods. We examined the effect of the extract and its main compound, berberine, on LPS-induced inflammatory activity in a murine macrophage cell line. RAW 264.7 cells were stimulated with LPS and incubated with either Rhizoma coptidis extract or berberine. Activation of AP-1 and NFκB was analyzed in nuclear extracts, secretion of MCP-1/CCL2 was measured in supernatants. Results. Incubation with Rhizoma coptidis and berberine strongly inhibited LPS-induced monocyte chemoattractant protein (MCP)-1 production in RAW cells. Activation of the transcription factors AP-1 and NFκB was inhibited by Rhizoma coptidis in a dose- and time-dependent fashion. Conclusions. Rhizoma coptidis extract inhibits LPS-induced MCP-1/CCL2 production in vitro via an AP-1 and NFκB-dependent pathway. Anti-inflammatory action of the extract is mediated mainly by its alkaloid compound berberine. PMID:20652055

  6. Design of Low Power Multiplier with Energy Efficient Full Adder Using DPTAAL

    Directory of Open Access Journals (Sweden)

    A. Kishore Kumar

    2013-01-01

    Full Text Available Asynchronous adiabatic logic (AAL is a novel lowpower design technique which combines the energy saving benefits of asynchronous systems with adiabatic benefits. In this paper, energy efficient full adder using double pass transistor with asynchronous adiabatic logic (DPTAAL is used to design a low power multiplier. Asynchronous adiabatic circuits are very low power circuits to preserve energy for reuse, which reduces the amount of energy drawn directly from the power supply. In this work, an 8×8 multiplier using DPTAAL is designed and simulated, which exhibits low power and reliable logical operations. To improve the circuit performance at reduced voltage level, double pass transistor logic (DPL is introduced. The power results of the proposed multiplier design are compared with the conventional CMOS implementation. Simulation results show significant improvement in power for clock rates ranging from 100 MHz to 300 MHz.

  7. Design of a High Linearity Four-Quadrant Analog Multiplier in Wideband Frequency Range

    Directory of Open Access Journals (Sweden)

    Abdul kareem Mokif Obais

    2017-05-01

    Full Text Available In this paper, a voltage mode four quadrant analog multiplier in the wideband frequency rangeis designed using a wideband operational amplifier (OPAMP and squaring circuits. The wideband OPAMP is designed using 10 identical NMOS transistorsand operated with supply voltages of ±12V. Two NMOS transistors and two wideband OPAMP are utilized in the design of the proposed squaring circuit. All the NMOS transistors are based on 0.35µm NMOStechnology. The multiplier has input and output voltage ranges of ±10 V, high range of linearity from -10 V to +10 V, and cutoff frequency of about 5 GHz. The proposed multiplier is designed on PSpice in Orcad 16.6

  8. Proposal for electro-optic multiplier based on dual transverse electro-optic Kerr effect.

    Science.gov (United States)

    Li, Changsheng

    2008-10-20

    A novel electro-optic multiplier is proposed, which can perform voltage multiplication operation by use of the Kerr medium exhibiting dual transverse electro-optic Kerr effect. In this kind of Kerr medium, electro-optic phase retardation is proportional to the square of its applied electric field, and orientations of the field-induced birefringent axes are only related to the direction of the field. Based on this effect, we can design an electro-optic multiplier by selecting the crystals of 6/mmm, 432, and m3m classes and isotropic Kerr media such as glass. Simple calculation demonstrates that a kind of glass-ceramic material with a large Kerr constant can be used for the design of the proposed electro-optic multiplier.

  9. Economic Multipliers and Sectoral Linkages: Ghana and the New Oil Sector

    Directory of Open Access Journals (Sweden)

    Dennis Nchor

    2016-01-01

    Full Text Available The study seeks to assess the structure of the economy of Ghana in terms of changes in the economic structure before and after the production of oil in commercial quantities. This is viewed with regards to economic multipliers, sectoral interdependence and trade concentration. The results show that changes occurred with regards to multipliers and sectoral interdependence. The output multipliers of most sectors have declined. The results also show that the agricultural sector experienced an initial decline in its growth while industry experienced an increase. The performance of the services sector was relatively stable for the period covered by the study. There is a decline in the level of trade concentration though on a whole the concentration index is still high. The study employed input-output modeling techniques and the data was obtained from the Ghana statistical service and the World Development Indicators.

  10. The properties of gas-phase multiply charged ions

    International Nuclear Information System (INIS)

    Newson, K.A.

    1999-01-01

    This thesis presents the results of a series of experiments investigating the reactivity of gas-phase molecular dications with various neutral collision partners, at collision energies between 3 and 13 eV in the laboratory frame, using a crossed-beam apparatus. The experiment involves the measurement of product ion intensities, which are determined by means of time-of-flight mass spectrometry. The experimental apparatus and methodology, together with the areas of theory important to ion chemistry, are described in the thesis. The product ions of greatest interest are those ions formed by bond-forming (chemical) reactivity. The relative intensities of such product ions, and those ions formed as a result of electron-transfer reactions, are, when recorded as a function of the collision energy, a powerful probe of the reaction mechanism. Additionally, where appropriate, the reactions are examined for isotope effects by using the isotopic analogue of the neutral collision partner. The results of the experiments indicate that no intermolecular isotope effects are present in the reactions of CF 2 2+ and CF 3 2+ with H 2 and D 2 neutral targets. In addition, the observed collision energy dependence is symptomatic of the absence of a barrier to reaction. These observations suggest that the reactions proceed via an impulsive direct reaction mechanism. Such a conclusion casts doubt on the applicability of the Landau-Zener model of H - /D - transfer reactivity. Other results presented in this thesis include the first reported observation of a bond-forming reaction between a molecular dication (CF2 2+ ) and a polyatomic neutral species (NH 3 ). Finally, the branching ratio of the products of bond-forming reactions between CF 2 2+ with HD indicates the operation of a strong intramolecular isotope effect, favouring the formation of the deuterated product. This observation points to a reaction mechanism in which the bond-formation is preceded by electron-transfer. (author)

  11. Spectral multipliers on spaces of distributions associated with non-negative self-adjoint operators

    DEFF Research Database (Denmark)

    Georgiadis, Athanasios; Nielsen, Morten

    2018-01-01

    and Triebel–Lizorkin spaces with full range of indices is established too. As an application, we obtain equivalent norm characterizations for the spaces mentioned above. Non-classical spaces as well as Lebesgue, Hardy, (generalized) Sobolev and Lipschitz spaces are also covered by our approach.......We consider spaces of homogeneous type associated with a non-negative self-adjoint operator whose heat kernel satisfies certain upper Gaussian bounds. Spectral multipliers are introduced and studied on distributions associated with this operator. The boundedness of spectral multipliers on Besov...

  12. Angular distribution of 662keV multiply-Compton scattered gamma rays in copper

    International Nuclear Information System (INIS)

    Singh, Manpreet; Singh, Gurvinderjit; Sandhu, B.S.; Singh, Bhajan

    2007-01-01

    The angular distribution of multiple Compton scattering of 662keV gamma photons, obtained from six Curie 137 Cs source, incident on copper scatterer of varying thickness is studied experimentally in both the forward and backward hemispheres. The scattered photons are detected by a 51mmx51mm NaI(Tl) scintillation detector. The full-energy peak corresponding to singly scattered events is reconstructed analytically. We observe that the numbers of multiply scattered events, having same energy as in the singly scattered distribution, first increases with increase in target thickness and then saturate. The optimum thickness at which the multiply scattered events saturate is determined at different scattering angles

  13. Effects of postharvest application of 1-MCP and postcutting dip treatment on the quality and nutritional properties of fresh-cut kiwifruit.

    Science.gov (United States)

    Antunes, Maria D C; Dandlen, Susana; Cavaco, Ana M; Miguel, Graça

    2010-05-26

    Consumption of minimally processed fruit and vegetables has increased significantly in the past few years due to the consumers' life style. The aim of this study was to evaluate the effect of treatment with ascorbic acid or calcium chloride on the quality parameters of fresh-cut kiwifruit prepared from fruit previously stored for 3 months, either treated or not treated with 1-methylcyclopropene (1-MCP) before storage. Harvested fruit were treated with 1 microL L(-1) 1-MCP for 20 h at room temperature ( approximately 20 degrees C) (MCP) or had no treatment (C) and were then stored at 0 degrees C. After 3 months, fruit were removed from storage, peeled, and cut longitudinally in quarters, dipped in 2% ascorbic acid (Asc), 2% calcium chloride (Ca), or just water (cont), and kept at 2 degrees C for 8 days. Measurements of firmness, soluble solids content (SSC) ( degrees Brix), color (CIE L*, a*, b*), electrolyte leakage, sugars, organic acids, total phenolics, and antioxidant activity (DPPH and ABTS) were performed at 0, 4, and 8 days. A taste panel was performed on the seventh shelf life day. It was shown that whole MCP-treated kiwifruit kept better than the control through the 3 months storage, this effect being lost through the fresh-cut shelf life period. Furthermore, the postcut dip on 2% CaCl(2) was effective on delaying softening and browning of fresh-cut kiwifruit, which were also the fruit preferred by panelists. Both ascorbic acid and CaCl(2) were effective on preserving or improving nutritional properties (phenolics, ascorbic acid, DPPH, and ABTS) mainly in the first 4 days of shelf life. The CaCl(2) had a further beneficial effect until 8 shelf life days. It is suggested that CaCl(2) is better in keeping overall quality through 8 days of shelf life at 2 degrees C in fresh-cut kiwifruit followed by Asc, and 1-MCP has negligible effect in the conditions of this experiment.

  14. Preservação dos atributos físicos de frutos de atemoia cv. Gefner com o uso de 1-MCP e atmosfera modificad

    Directory of Open Access Journals (Sweden)

    Gláucia Michelle Cosme Silva

    2014-12-01

    Full Text Available O interesse comercial pela atemoia vem aumentando cada vez mais no Brasil. O aumento da atividade respiratória, acompanhado por modificações rápidas na composição física dos frutos podem inviabilizar sua distribuição a mercados distantes. Neste contexto, objetivou-se com o presente trabalho avaliar os atributos físicos em frutos de atemoia tratados com 1-metilciclopropeno (1-MCP e atmosfera modificada associados à refrigeração. O experimento foi instalado em delineamento experimental inteiramente casualizado, em esquema fatorial 4x5, sendo quatro concentrações de 1-MCP (0; 200; 400 e 600 ŋL L-¹ e cinco períodos de avaliação após a colheita, em intervalo de cinco dias, com quatro repetições e quatro frutos por unidade experimental. As atemoias foram colhidas em pomar comercial, no município de Matias Cardoso-MG, no estádio de maturação fisiológica, lavadas, sanitizadas e secas ao ar, depois tratadas com as concentrações de 1-MCP por oito horas, em temperatura ambiente. Logo após, quatro frutos foram dispostos em bandejas de poliestireno expandido. Alguns permaneceram sem membrana, enquanto outros foram embalados com membrana plástica de PEBD 16µm. As variáveis avaliadas nos frutos foram: perda de biomassa fresca, firmeza, concentração de CO2, etileno e coloração da casca. O uso da atmosfera modificada e do 1-MCP, associados ou não, foi eficiente no atraso do amadurecimento dos frutos, permitindo a conservação de sua qualidade física. Frutos tratados com 1-MCP apresentaram-se mais firmes, além da preservação da coloração, verificada através da luminosidade, cromaticidade e ângulo Hueº, que se mostraram superiores quando comparados aos frutos não tratados.

  15. Electron cloud observations at the ISIS Proton Synchrotron

    CERN Document Server

    Pertica, A.

    2013-04-22

    The build up of electron clouds inside a particle accelerator vacuum chamber can produce strong transverse and longitudinal beam instabilities which in turn can lead to high levels of beam loss often requiring the accelerator to be run below its design specification. To study the behaviour of electron clouds at the ISIS Proton Synchrotron, a Micro-Channel Plate (MCP) based electron cloud detector has been developed. The detector is based on the Retarding Field Analyser (RFA) design and consists of a retarding grid, which allows energy analysis of the electron signal, and a MCP assembly placed in front of the collector plate. The MCP assembly provides a current gain over the range 300 to 25K, thereby increasing the signal to noise ratio and dynamic range of the measurements. This paper presents the first electron cloud observations at the ISIS Proton Synchrotron. These results are compared against signals from a beam position monitor and a fast beam loss monitor installed at the same location.

  16. The size and spatial distribution of microchannel plate output electron clouds

    International Nuclear Information System (INIS)

    Lapington, J.S.; Edgar, M.L.

    1989-01-01

    An experimental technique for measuring the spatial distribution of the output charge cloud from a microchannel plate (MCP), using a planar, charge-division-type anode is discussed. The anode simultaneously measures, for each charge cloud, both the position of the charge centroid and the fractional charge falling to one side of the split in the pattern. The measurements from several thousand events have been combined to calculate the average spatial distribution of the electron cloud and the dominant factors influencing the charge cloud distribution have been found to be the MCP gain and the MCP-anode accelerating field and geometry. Experimental research on the two dominant factors with respect to ranges of distribution is presented. 10 refs

  17. The correspondence between stochastic mechanics and quantum mechanics on multiply connected configuration spaces

    International Nuclear Information System (INIS)

    Carlen, E.A.; Loffredo, M.I.

    1989-01-01

    We show how to obtain a complete correspondence between stochastic and quantum mechanics on multiply connected spaces. We do this by introducing a stochastic mechanical analog of the hydrodynamical circulation, relating it to the topological properties of the configuration space, and using it to constrain the stochastic mechanical variational principles. (orig.)

  18. An Exploration of Social Media Use among Multiply Minoritized LGBTQ Youth

    Science.gov (United States)

    Lucero, Alfie Leanna

    2013-01-01

    This study responds to a need for research in a fast-growing and significant area of study, that of exploring, understanding, and documenting the numerous ways that multiply marginalized LGBTQ youth between the ages of 14 and 17 use social media. The primary research question examined whether social media provide safe spaces for multiply…

  19. New Lagrange Multipliers for the Blind Adaptive Deconvolution Problem Applicable for the Noisy Case

    Directory of Open Access Journals (Sweden)

    Monika Pinchas

    2016-02-01

    Full Text Available Recently, a new blind adaptive deconvolution algorithm was proposed based on a new closed-form approximated expression for the conditional expectation (the expectation of the source input given the equalized or deconvolutional output where the output and input probability density function (pdf of the deconvolutional process were approximated with the maximum entropy density approximation technique. The Lagrange multipliers for the output pdf were set to those used for the input pdf. Although this new blind adaptive deconvolution method has been shown to have improved equalization performance compared to the maximum entropy blind adaptive deconvolution algorithm recently proposed by the same author, it is not applicable for the very noisy case. In this paper, we derive new Lagrange multipliers for the output and input pdfs, where the Lagrange multipliers related to the output pdf are a function of the channel noise power. Simulation results indicate that the newly obtained blind adaptive deconvolution algorithm using these new Lagrange multipliers is robust to signal-to-noise ratios (SNR, unlike the previously proposed method, and is applicable for the whole range of SNR down to 7 dB. In addition, we also obtain new closed-form approximated expressions for the conditional expectation and mean square error (MSE.

  20. Dynamics of chemical reactions of multiply-charged cations: Information from beam scattering experiments

    Czech Academy of Sciences Publication Activity Database

    Herman, Zdeněk

    2015-01-01

    Roč. 378, FEB 2015 (2015), s. 113-126 ISSN 1387-3806 Institutional support: RVO:61388955 Keywords : Multiply-charged ions * Dynamics of chemical reactions * Beam scattering Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.183, year: 2015

  1. The impact of founder events on chromosomal variability in multiply mating species

    DEFF Research Database (Denmark)

    Pool, John E; Nielsen, Rasmus

    2008-01-01

    size reductions and recent bottlenecks leading to decreased X/A diversity ratios. Here we use theory and simulation to investigate a separate demographic effect-that of founder events involving multiply mated females-and find that it leads to much stronger reductions in X/A diversity ratios than...

  2. Strength of the reversible, garbage-free 2 k ±1 multiplier

    DEFF Research Database (Denmark)

    Rotenberg, Eva; Cranch, James; Thomsen, Michael Kirkedal

    2013-01-01

    Recently, a reversible garbage-free 2 k ±1 constant-multiplier circuit was presented by Axelsen and Thomsen. This was the first construction of a garbage-free, reversible circuit for multiplication with non-trivial constants. At the time, the strength, that is, the range of constants obtainable...

  3. Training Pragmatic Language Skills through Alternate Strategies with a Blind Multiply Handicapped Child.

    Science.gov (United States)

    Evans, C. J.; Johnson, C. J.

    1988-01-01

    A blind multiply handicapped preschooler was taught to respond appropriately to two adjacency pair types ("where question-answer" and "comment-acknowledgement"). The two alternative language acquisition strategies available to blind children were encouraged: echolalia to maintain communicative interactions and manual searching…

  4. Pointwise Multipliers on Spaces of Homogeneous Type in the Sense of Coifman and Weiss

    Directory of Open Access Journals (Sweden)

    Yanchang Han

    2014-01-01

    homogeneous type in the sense of Coifman and Weiss, pointwise multipliers of inhomogeneous Besov and Triebel-Lizorkin spaces are obtained. We make no additional assumptions on the quasi-metric or the doubling measure. Hence, the results of this paper extend earlier related results to a more general setting.

  5. Best approximation of the Dunkl Multiplier Operators Tk,ℓ,m

    Directory of Open Access Journals (Sweden)

    Fethi Soltani

    2015-03-01

    Full Text Available We study some class of Dunkl multiplier operators Tk,ℓ,m; and we give for them an application of the theory of reproducing kernels to the Tikhonov regularization,which gives the best approximation of the operators Tk,ℓ,m on a Hilbert spaces Hskℓ.

  6. Composite Field Multiplier based on Look-Up Table for Elliptic Curve Cryptography Implementation

    Directory of Open Access Journals (Sweden)

    Marisa W. Paryasto

    2013-09-01

    Full Text Available Implementing a secure cryptosystem requires operations involving hundreds of bits. One of the most recommended algorithm is Elliptic Curve Cryptography (ECC. The complexity of elliptic curve algorithms and parameters with hundreds of bits requires specific design and implementation strategy. The design architecture must be customized according to security requirement, available resources and parameter choices. In this work we propose the use of composite field to implement finite field multiplication for ECC implementation. We use 299-bit keylength represented in GF((21323 instead of in GF(2299. Composite field multiplier can be implemented using different multiplier for ground-field and for extension field. In this paper, LUT is used for multiplication in the ground-field and classic multiplieris used for the extension field multiplication. A generic architecture for the multiplier is presented. Implementation is done with VHDL with the target device Altera DE2. The work in this paper uses the simplest algorithm to confirm the idea that by dividing field into composite, use different multiplier for base and extension field would give better trade-off for time and area. This work will be the beginning of our more advanced further research that implements composite-field using Mastrovito Hybrid, KOA and LUT.

  7. Structural brain network analysis in families multiply affected with bipolar I disorder

    NARCIS (Netherlands)

    Forde, Natalie J.; O'Donoghue, Stefani; Scanlon, Cathy; Emsell, Louise; Chaddock, Chris; Leemans, Alexander; Jeurissen, Ben; Barker, Gareth J.; Cannon, Dara M.; Murray, Robin M.; McDonald, Colm

    2015-01-01

    Disrupted structural connectivity is associated with psychiatric illnesses including bipolar disorder (BP). Here we use structural brain network analysis to investigate connectivity abnormalities in multiply affected BP type I families, to assess the utility of dysconnectivity as a biomarker and its

  8. Discrete Green’s function diakoptics for stable FDTD interaction between multiply-connected domains

    NARCIS (Netherlands)

    Hon, de B.P.; Arnold, J.M.; Graglia, R.D.

    2007-01-01

    We have developed FDTD boundary conditions based on discrete Green's function diakoptics for arbitrary multiply-connected 2D domains. The associated Z-domain boundary operator is symmetric, with an imaginary part that can be proved to be positive semi-definite on the upper half of the unit circle in

  9. Composite Field Multiplier based on Look-Up Table for Elliptic Curve Cryptography Implementation

    Directory of Open Access Journals (Sweden)

    Marisa W. Paryasto

    2012-04-01

    Full Text Available Implementing a secure cryptosystem requires operations involving hundreds of bits. One of the most recommended algorithm is Elliptic Curve Cryptography (ECC. The complexity of elliptic curve algorithms and parameters with hundreds of bits requires specific design and implementation strategy. The design architecture must be customized according to security requirement, available resources and parameter choices. In this work we propose the use of composite field to implement finite field multiplication for ECC implementation. We use 299-bit keylength represented in GF((21323 instead of in GF(2299. Composite field multiplier can be implemented using different multiplier for ground-field and for extension field. In this paper, LUT is used for multiplication in the ground-field and classic multiplieris used for the extension field multiplication. A generic architecture for the multiplier is presented. Implementation is done with VHDL with the target device Altera DE2. The work in this paper uses the simplest algorithm to confirm the idea that by dividing field into composite, use different multiplier for base and extension field would give better trade-off for time and area. This work will be the beginning of our more advanced further research that implements composite-field using Mastrovito Hybrid, KOA and LUT.

  10. Time-area efficient multiplier-free recursive filter architectures for FPGA implementation

    DEFF Research Database (Denmark)

    Shajaan, Mohammad; Sørensen, John Aasted

    1996-01-01

    Simultaneous design of multiplier-free recursive filters (IIR filters) and their hardware implementation in Xilinx field programmable gate array (XC4000) is presented. The hardware design methodology leads to high performance recursive filters with sampling frequencies in the interval 15-21 MHz (...

  11. Time-area efficient multiplier-free filter architectures for FPGA implementation

    DEFF Research Database (Denmark)

    Shajaan, Mohammad; Nielsen, Karsten; Sørensen, John Aasted

    1995-01-01

    Simultaneous design of multiplier-free filters and their hardware implementation in Xilinx field programmable gate array (XC4000) is presented. The filter synthesis method is a new approach based on cascade coupling of low order sections. The complexity of the design algorithm is 𝒪 (filter o...

  12. Testing of money multiplier model for Pakistan: does monetary base carry any information?

    Directory of Open Access Journals (Sweden)

    Muhammad Arshad Khan

    2010-02-01

    Full Text Available This paper tests the constancy and stationarity of mechanic version of the money multiplier model for Pakistan using monthly data over the period 1972M1-2009M2. We split the data into pre-liberalization (1972M1-1990M12 and post-liberalization (1991M1-2009M2 periods to examine the impact of financial sector reforms. We first examine the constancy and stationarity of the money multiplier and the results suggest the money multiplier remains non-stationary for the entire sample period and sub-periods. We then tested cointegration between money supply and monetary base and find the evidence of cointegration between two variables for the entire period and two sub-periods. The coefficient restrictions are satisfied only for the post-liberalization period. Two-way long-run causality between money supply and monetary base is found for the entire period and post-liberalization. For the post-liberalization period the evidence of short-run causality running from monetary base to money supply is also identified. On the whole, the results suggest that money multiplier model can serve as framework for conducting short-run monetary policy in Pakistan. However, the monetary authority may consider the co-movements between money supply and reserve money at the time of conducting monetary policy.

  13. Implementation of neutron activation analysis in the neutron multiplier CS-ISCTN (first part)

    International Nuclear Information System (INIS)

    Contreras, R.; Ixquiac, M.; Hernandez, O.; Herrera, E.F.; Diaz, O.; Lopez, R.; Alvarez, I.; Manso, M.V.; Padron, G.; D Alessandro, K.

    1997-01-01

    The detection limit of 32 elements are determined after experimental evaluation of the neutron flux components in the irradiation position of the neutron multiplier CS-ISCTN. The control of the thermal flux was carry up, comparing the experimental results obtained through three convention used determination of the reaction rate, with the theoretical obtained before

  14. Counting efficiency for liquid scintillator systems with a single multiplier phototube

    International Nuclear Information System (INIS)

    Grau Malonda, A.; Garcia-Torano, E.

    1984-01-01

    In this paper counting efficiency as a function of a free parameter (the figure of merit) has been computed. The results are applicable to liquid scintillator systems with a single multiplier phototube. Tables of counting efficiency for 62 pure beta emitters are given for figures of merit in the range 0.25 to 50. (Author) 16 refs

  15. Fourier Multipliers on Decomposition Spaces of Modulation and Triebel–Lizorkin Type

    DEFF Research Database (Denmark)

    Cleanthous, G.; Georgiadis, Athanasios; Nielsen, Morten

    2018-01-01

    spaces in both the isotropic and an anisotropic setting. We derive a boundedness result for Fourier multipliers on anisotropic decomposition spaces of modulation and Triebel–Lizorkin type. As an application, we obtain equivalent quasi-norm characterizations for this class of decomposition spaces....

  16. Evaluation of multiplier effect of housing investments in the city economy

    Science.gov (United States)

    Ovsiannikova, T.; Rabtsevich, O.; Yugova, I.

    2017-01-01

    The given study presents evaluation of the role and significance of housing investments providing stable social and economic development of a city. It also justifies multiplier impact of investments in housing construction on all the sectors of urban economy. Growth of housing investments generates multiplier effect triggering the development of other different interrelated sectors. The paper suggests approach developed by the authors to evaluate the level of city development. It involves defining gross city product on the basis of integral criterion of gross value added of types of economic activities in the city economy. The algorithm of gross value added generation in urban economy is presented as a result of multiplier effect of housing investments. The evaluation of the mentioned effect was shown on the case of the city of Tomsk (Russia). The study has revealed that multiplier effect allows obtaining four rubles of added value out of one ruble of housing investments in the city economy. Methods used in the present study include the ones of the System of National Accounts, as well as methods of statistical and structural analysis. It has been proved that priority investment in housing construction is considered to be the key factor for stable social and economic development of the city. Developed approach is intended for justification of priority directions in municipal and regional investment policy. City and regional governing bodies and potential investors are the ones to apply the given approach.

  17. Ultra-low-power, class-AB, CMOS four-quadrant current multiplier

    NARCIS (Netherlands)

    Sawigun, C.; Serdijn, W.A.

    2009-01-01

    A class-AB four-quadrant current multiplier constituted by a class-AB current amplifier and a current splitter which can handle input signals in excess of ten times the bias current is presented. The proposed circuit operation is based on the exponential characteristic of BJTs or subthreshold

  18. Mixed Analog/Digital Matrix-Vector Multiplier for Neural Network Synapses

    DEFF Research Database (Denmark)

    Lehmann, Torsten; Bruun, Erik; Dietrich, Casper

    1996-01-01

    In this work we present a hardware efficient matrix-vector multiplier architecture for artificial neural networks with digitally stored synapse strengths. We present a novel technique for manipulating bipolar inputs based on an analog two's complements method and an accurate current rectifier...

  19. Radiation-hardened I2L 8*8 multiplier circuit

    International Nuclear Information System (INIS)

    Doyle, B.R.; Kreps, S.A.; Van Vonno, N.W.; Lake, G.W.

    1979-01-01

    Development of improved Substrate Fed I 2 L (SFL) processing has been combined with geometry and fanout constraints to design a radiation hardened LSI 8.8 Multiplier. This study describes details of the process and circuit design and gives resultant electrical and radiation test performance

  20. Full inelastic cross section, effective stopping and ranges of fast multiply charged ions

    International Nuclear Information System (INIS)

    Alimov, R.A.; Arslanbekov, T.U.; Matveev, B.I.; Rakhmatov, A.S.

    1994-01-01

    Inelastic processes taking place in collision of fast multiply charged ions with atoms are considered on the base of mechanism of sudden momentum transfer. The simple estimations are proposed of full inelastic cross sections, effective stopping and ion ranges in gaseous medium. (author). 10 refs