WorldWideScience

Sample records for clic pets structure

  1. Wakefield Simulation of CLIC PETS Structure Using Parallel 3D Finite Element Time-Domain Solver T3P

    Energy Technology Data Exchange (ETDEWEB)

    Candel, A.; Kabel, A.; Lee, L.; Li, Z.; Ng, C.; Schussman, G.; Ko, K.; /SLAC; Syratchev, I.; /CERN

    2009-06-19

    In recent years, SLAC's Advanced Computations Department (ACD) has developed the parallel 3D Finite Element electromagnetic time-domain code T3P. Higher-order Finite Element methods on conformal unstructured meshes and massively parallel processing allow unprecedented simulation accuracy for wakefield computations and simulations of transient effects in realistic accelerator structures. Applications include simulation of wakefield damping in the Compact Linear Collider (CLIC) power extraction and transfer structure (PETS).

  2. Development and testing of a double length pets for the CLIC experimental area

    CERN Document Server

    Sánchez, L; Gavela, D; Lara, A; Rodríguez, E; Gutiérrez, J L; Calero, J; Toral, F; Samoshkin, A; Gudkov, D; Riddone, G

    2014-01-01

    CLIC (compact linear collider) is a future e þ e collider based on normal-conducting technology, currently under study at CERN. Its design is based on a novel two-beam acceleration scheme. The main beam gets RF power extracted from a drive beam through power extraction and transfer structures (PETS). The technical feasibility of CLIC is currently being proved by its Third Test Facility (CTF3) which includes the CLIC experimental area (CLEX). Two Double Length CLIC PETS will be installed in CLEX to validate their performance with beam. This paper is focused on the engineering design, fabrication and validation of this PETS fi rst prototype. The design consists of eight identical bars, separated by radial slots in which damping material is located to absorb transverse wake fi elds, and two compact couplers placed at both ends of the bars to extract the generated power. The PETS bars are housed inside a vacuum tank designed to make the PETS as compact as possible. Several joint techniques such as vacuum brazing...

  3. Development and testing of a double length pets for the CLIC experimental area

    Science.gov (United States)

    Sánchez, L.; Carrillo, D.; Gavela, D.; Lara, A.; Rodríguez, E.; Gutiérrez, J. L.; Calero, J.; Toral, F.; Samoshkin, A.; Gudkov, D.; Riddone, G.

    2014-05-01

    CLIC (compact linear collider) is a future e+e- collider based on normal-conducting technology, currently under study at CERN. Its design is based on a novel two-beam acceleration scheme. The main beam gets RF power extracted from a drive beam through power extraction and transfer structures (PETS). The technical feasibility of CLIC is currently being proved by its Third Test Facility (CTF3) which includes the CLIC experimental area (CLEX). Two Double Length CLIC PETS will be installed in CLEX to validate their performance with beam. This paper is focused on the engineering design, fabrication and validation of this PETS first prototype. The design consists of eight identical bars, separated by radial slots in which damping material is located to absorb transverse wakefields, and two compact couplers placed at both ends of the bars to extract the generated power. The PETS bars are housed inside a vacuum tank designed to make the PETS as compact as possible. Several joint techniques such as vacuum brazing, electron beam and arc welding were used to complete the assembly. Finally, several tests such as dimensional control and leak testing were carried out to validate design and fabrication methods. In addition, RF measurements at low power were made to study frequency tuning.

  4. New clic-g structure design

    CERN Document Server

    AUTHOR|(CDS)2082335

    2016-01-01

    The baseline design of the Compact Linear Collider main linac accelerating structure is called ‘CLIC-G’. It is described in the CLIC Conceptual Design Report (CDR) [1]. As shown in Fig. 1, a regular cell of the structure has four waveguides to damp unwanted high-order-modes (HOMs). These waveguides are dimensioned to cut off the fundamental working frequency in order to prevent the degradation of the fundamental mode Q-factor. The cell geometry and HOM damping loads had been extensively optimized in order to maximize the RF-to-beam efficiency, to minimize the cost, and to meet the beam dynamics and the high gradient RF constraints [2

  5. Wakefield monitor development for CLIC accelerating structure

    CERN Document Server

    Peauger, F; Girardot, P; Andersson, A; Riddone, G; Samoshkin, A; Solodko, A; Zennaro, R; Ruber, R

    2010-01-01

    Abstract To achieve high luminosity in CLIC, the accelerating structures must be aligned to an accuracy of 5 μm with respect to the beam trajectory. Position detectors called Wakefield Monitors (WFM) are integrated to the structure for a beam based alignment. This paper describes the requirements of such monitors. Detailed RF design and electromagnetic simulations of the WFM itself are presented. In particular, time domain computations are performed and an evaluation of the resolution is done for two higher order modes at 18 and 24 GHz. The mechanical design of a prototype accelerating structure with WFM is also presented as well as the fabrication status of three complete structures. The objective is to implement two of them in CTF3 at CERN for a feasibility demonstration with beam and high power rf.

  6. Wakefield Computations for the CLIC PETS using the Parallel Finite Element Time-Domain Code T3P

    Energy Technology Data Exchange (ETDEWEB)

    Candel, A; Kabel, A.; Lee, L.; Li, Z.; Ng, C.; Schussman, G.; Ko, K.; /SLAC; Syratchev, I.; /CERN

    2009-06-19

    In recent years, SLAC's Advanced Computations Department (ACD) has developed the high-performance parallel 3D electromagnetic time-domain code, T3P, for simulations of wakefields and transients in complex accelerator structures. T3P is based on advanced higher-order Finite Element methods on unstructured grids with quadratic surface approximation. Optimized for large-scale parallel processing on leadership supercomputing facilities, T3P allows simulations of realistic 3D structures with unprecedented accuracy, aiding the design of the next generation of accelerator facilities. Applications to the Compact Linear Collider (CLIC) Power Extraction and Transfer Structure (PETS) are presented.

  7. The 30 GHz transfer structure for the CLIC study

    CERN Document Server

    Carron, G; Thorndahl, L

    1998-01-01

    In the so-called "Two-Beam Acceleration Scheme" the energy of a drive beam is converted to rf power by means of a "Transfer Structure", which plays the role of power source. In the Transfer Structure the bunched drive beam is decelerated by the electromagnetic field which it induces and builds up by the coherent interaction of successive bunches with the chosen longitudinal mode. The CLIC Transfer Structure is original in that it operates at 30 GHz and uses teeth-like corrugations to slow down the hybrid TM mode to make it synchronous with the drive beam. The beam energy is transformed into rf power, which travels along the structure and is collected by the output couplers. The 30 GHz rf power is then transported by means of two waveguides to two main linac disk-loaded accelerating structures. This report describes the CLIC Transfer Structure design, 3-D computer simulations, model construction and measure-ments as well as the prototype construction and testing with the low energy beam in the CLIC Test Facili...

  8. On structure design for the CLIC Booster Linac

    CERN Document Server

    Darvish, Esmat

    2015-01-01

    Using the SUPERFISH code we present a design for a traveling wave (TW) structure of the Booster Linac for CLIC. The structure, consisting of thirty asymmetric cells attached to the beam pipes at two ends, works in 2π/3 operating mode at working frequency 2 GHz. For the corresponding operating mode and frequency, the RF field configuration transmitted through the cavity is obtained. The results are prepared in an RF field data file to be used in the PARMELA code for further beam dynamic study.

  9. An Asset Test of the CLIC Accelerating Structure

    International Nuclear Information System (INIS)

    Transverse wakefield suppression in the CLIC (Compact Linear Collider) multibunch accelerating structure, called the TDS (Tapered Damped Structure), is achieved primarily through heavy damping. In order to verify the performance of the TDS design and the validity of the theoretical tools used to model it, a 15 GHz version of the TDS has been constructed and tested in the ASSET facility at SLAC. The test has directly demonstrated transverse wakefield suppression of over a factor 100, with an excellent agreement between the measured and the calculated wakefield

  10. Status of the Fatigue Studies on the CLIC Accelerating Structures

    CERN Document Server

    Calatroni, S; Neupert, H; Wuensch, Walter; CERN. Geneva

    2006-01-01

    The need for high accelerating gradients for the future multi-TeV e+e- Compact Linear Collider (CLIC) imposes considerable constraints on the materials of the accelerating structures. The surfaces exposed to high pulsed RF (Radio Frequency) currents are subject to cyclic thermal stresses which are expected to induce surface break up by fatigue. Since no fatigue data exists in the literature up to very large numbers of cycles and for the particular stress pattern present in RF cavities, a comprehensive study of copper alloys in this parameter range has been initiated. Fatigue data for selected copper alloys in different states are presented

  11. Choke-Mode Damped Structure Design for the CLIC Main Linac

    CERN Document Server

    Zha, Hao; Tang, Chuanxiang; Huang, Wenhui; Shi, Jiaru; Grudiev, Alexej; Wuensch, Walter

    2012-01-01

    Choke-mode damped structures are being studied as an alternative design for the accelerating structures of main linacs of the compact linear collider (CLIC). Choke-mode structures have the potential for much lower pulsed temperature rise, and lower cost of manufacture and fabrication. A new kind of choke-mode structure was proposed and simulated by Gdfidl. This structures has comparable wakefield damping effect as the baseline design of CLIC main linacs.

  12. Vacuum arc localization in CLIC prototype radio frequency accelerating structures

    CERN Document Server

    AUTHOR|(CDS)2091976; Koivunen, Visa

    2016-04-04

    A future linear collider capable of reaching TeV collision energies should support accelerating gradients beyond 100 MV/m. At such high fields, the occurrence of vacuum arcs have to be mitigated through conditioning, during which an accelerating structure’s resilience against breakdowns is slowly increased through repeated radio frequency pulsing. Conditioning is very time and resource consuming, which is why developing more efficient procedures is desirable. At CERN, conditioning related research is conducted at the CLIC high-power X-band test stands. Breakdown localization is an important diagnostic tool of accelerating structure tests. Abnormal position distributions highlight issues in structure design, manufacturing or operation and may consequently help improve these processes. Additionally, positioning can provide insight into the physics of vacuum arcs. In this work, two established positioning methods based on the time-difference-ofarrival of radio frequency waves are extended. The first method i...

  13. Thermal joining studies of CLIC accelerating structures and Establishment of a test bench and studies of thermomechanical behaviour of a CLIC two beam module

    CERN Document Server

    Rossi, Fabrizio

    2013-01-01

    The assembly procedure of the CLIC accelerating structures is constituted of several steps, involving ultra-precision machining, heating cycles at very high temperatures and many quality controls necessary to fulfil the very tight technical requirements. Diverse issues are related to the diffusion bonding process of CLIC accelerating structures; due to diffusion creep mechanisms occurring at high temperature and low stress, residual deformations might be present at the end of the joining process. A theoretical and experimental approach is presented here in order to understand this issue further and feedback on the design process. As a second issue tackled here, the final alignment of CLIC is also affected by the power dissipation occurring in the module during the normal operation modes and resulting in time-varying non-uniform thermal fields. The thermo-mechanical models of CLIC two-beam modules developed in the past are then useful to predict the structural deformations affecting the final alignment of the ...

  14. CLIC Drive Beam Phase Stabilisation

    CERN Document Server

    Gerbershagen, Alexander; Schulte, Daniel

    The thesis presents phase stability studies for the Compact Linear Collider (CLIC) and focuses in particular on CLIC Drive Beam longitudinal phase stabilisation. This topic constitutes one of the main feasibility challenges for CLIC construction and is an essential component of the current CLIC stabilisation campaign. The studies are divided into two large interrelated sections: the simulation studies for the CLIC Drive Beam stability, and measurements, data analysis and simulations of the CLIC Test Facility (CTF3) Drive Beam phase errors. A dedicated software tool has been developed for a step-by-step analysis of the error propagation through the CLIC Drive Beam. It uses realistic RF potential and beam loading amplitude functions for the Drive and Main Beam accelerating structures, complete models of the recombination scheme and compressor chicane as well as of further CLIC Drive Beam modules. The tool has been tested extensively and its functionality has been verified. The phase error propagation at CLIC h...

  15. Experimental study of DC vacuum breakdown and application to high-gradient accelerating structures for CLIC

    CERN Document Server

    Shipman, Nicholas; Jones, Roger

    2016-01-01

    The compact linear collider (CLIC) is a leading candidate for the next generation high energy linear collider. As any breakdown would result in a partial or full loss of luminosity for the pulse in which it occurs, obtaining a low breakdown rate in CLIC accelerating structures is a critical requirement for the successful operation of the proposed collider. This thesis presents investigations into the breakdown phenomenon primarily in the low breakdown rate regime of interest to CLIC, performed using the CERN DC spark systems between 2011 and 2014. The design, construction and commissioning of several new pieces of hardware, as well as the development of improved techniques to measuring the inter-electrode gap distance are detailed. These hardware improvements were fundamental in enabling the exciting new experiments mentioned below, which in turn have provided significant additional insight into the phenomenon of breakdown. Experiments were performed to measure fundamental parameters of individual breakdowns...

  16. Experimental Study of the Effect of Beam Loading on RF Breakdown Rate in CLIC High-Gradient Accelerating Structures

    CERN Document Server

    Tecker, F; Kelisani, M; Doebert, S; Grudiev, A; Quirante, J; Riddone, G; Syratchev, I; Wuensch, W; Kononenko, O; Solodko, A; Lebet, S

    2013-01-01

    RF breakdown is a key issue for the multi-TeV highluminosity e+e- Compact Linear Collider (CLIC). Breakdowns in the high-gradient accelerator structures can deflect the beam and decrease the desired luminosity. The limitations of the accelerating structures due to breakdowns have been studied so far without a beam present in the structure. The presence of the beam modifies the distribution of the electrical and magnetic field distributions, which determine the breakdown rate. Therefore an experiment has been designed for high power testing a CLIC prototype accelerating structure with a beam present in the CLIC Test Facility (CTF3). A special beam line allows extracting a beam with nominal CLIC beam current and duration from the CTF3 linac. The paper describes the beam optics design for this experimental beam line and the commissioning of the experiment with beam.

  17. Material studies in the frame of CLIC Accelerating structures production conducted within the Mechanics program together with Metso Oy

    CERN Document Server

    Nurminen, Janne

    2012-01-01

    MeChanICs (Marie Curie Linking Industry to CERN) is an Industry to Academia Partnership and Pathways (IAPP) platform for precision manufacturing knowledge exchange bringing together five Finnish manufacturing companies with Helsinki Insitute of Physics (HIP) and CERN. The scientific objective of MeChanICs project is to contribute to the manufacturing RTD of CLIC enabling technologies. The focus is on the design, materials, machining, brazing and assembly of A CLIC accelerating structure. This study deals with the materials work package of the program and wants to explore the following items: 1) producing copper accelerating structures for CLIC from raw copper powder by near net shape hot isostatic pressing (HIP). 2) The feasibility to use HIP diffusion bonding of the accelerator structures as a function of surface quality and applied temperature and pressure. 3) Brazing for CLIC AS auxiliary systems, like water cooling or damping manifolds, to the disc stack by coating one of the brazing partners with an enab...

  18. Wakefield and surface electromagnetic field optimisation of manifold damped accelerating structures for CLIC

    International Nuclear Information System (INIS)

    The main travelling wave linacs of the compact linear collider (CLIC) operate at a frequency of 11.9942 GHz with a phase advance per cell of 2π/3. In order to minimise the overall footprint of the accelerator, large accelerating gradients are sought. The present baseline design for the main linacs of CLIC demands an average electric field of 100 MV/m. To achieve this in practical cavities entails the dual challenges of minimising the potential for electrical breakdown and ensuring the beam excited wakefield is sufficiently suppressed. We present a design to meet both of these conditions, together with a description of the structure, CLICDDSA, expressively designed to experimentally test the ability of the structure to cope with high powers.

  19. Studies on high-precision machining and assembly of CLIC RF structures

    CERN Document Server

    Huopana, J; Riddone, G; Österberg, K

    2010-01-01

    The Compact Linear Collider (CLIC) is currently under development at CERN as a potential multi-TeV e+e– collider. The manufacturing and assembly tolerances for the required RF components are essential for the final efficiency and for the operation of CLIC. The proper function of an accelerating structure is sensitive to mechanical errors in the shape and the alignment of the accelerating cavity. The current tolerances are in the micron range. This raises challenges in the field of mechanical design and demands special manufacturing technologies and processes. Currently the mechanical design of the accelerating structures is based on a disk design. Alternatively, it is possible to create the accelerating assembly from quadrants, which has the potential to be favoured for the mass production due to simplicity and cost. In this case, the functional shape inside of the accelerating structure remains the same and a single assembly uses less parts. This paper focuses on the development work done in design and sim...

  20. Assembly Test of Elastic Averaging Technique to Improve Mechanical Alignment for Accelerating Structure Assemblies in CLIC

    CERN Document Server

    Huopana, J

    2010-01-01

    The CLIC (Compact LInear Collider) is being studied at CERN as a potential multi-TeV e+e- collider [1]. The manufacturing and assembly tolerances for the required RF-components are important for the final efficiency and for the operation of CLIC. The proper function of an accelerating structure is very sensitive to errors in shape and location of the accelerating cavity. This causes considerable issues in the field of mechanical design and manufacturing. Currently the design of the accelerating structures is a disk design. Alternatively it is possible to create the accelerating assembly from quadrants, which favour the mass manufacturing. The functional shape inside of the accelerating structure remains the same and a single assembly uses less parts. The alignment of these quadrants has been previously made kinematic by using steel pins or spheres to align the pieces together. This method proved to be a quite tedious and time consuming method of assembly. To limit the number of different error sources, a meth...

  1. Simulations and Vacuum Tests of a CLIC Accelerating Structure

    CERN Document Server

    Garion, C

    2011-01-01

    The Compact LInear Collider, under study, is based on room temperature high gradient structures. The vacuum specificities of these cavities are low conductance, large surface areas and a non-baked system. The main issue is to reach UHV conditions (typically 10-7 Pa) in a system where the residual vacuum is driven by water outgassing. A finite element model based on an analogy thermal/vacuum has been built to estimate the vacuum profile in an accelerating structure. Vacuum tests are carried out in a dedicated set-up, the vacuum performances of different configurations are presented and compared with the predictions.

  2. Simulation of the CLIC transfer structure by means of MAFIA

    Science.gov (United States)

    Millich, Antonio

    1993-12-01

    The function of the CTS is to extract 30 GHz power from the drive beam and to make it available for the acceleration of the main beam. The simulation of a six cells section of the CTS using the MAFIA set of codes has provided the designers of the structure with a set of RF parameters at 30 GHz. The frequency domain analysis has allowed the plotting of the dispersion curves for the first few pass bands, whereas the time domain analysis has provided results on the shape and magnitude of the longitudinal and transverse wake fields and of the loss factors.

  3. High-Gradient test results from a CLIC prototype accelerating structure : TD26CC

    CERN Document Server

    Degiovanni, A; Farabolini, W; Grudiev, A; Kovermann, J; Montessinos, E; Riddone, G; Syratchev, I; Wegner, R; Wuensch, W; Solodko, A; Woolley, B

    2014-01-01

    The CLIC study has progressively tested prototype accelerating structures which incorporate an ever increasing number of features which are needed for a final version ready to be installed in a linear collider. The most recent high power test made in the CERN X-band test stand, Xbox-1, is of a CERN-built prototype which includes damping features but also compact input and output power couplers, which maximize the overall length to active gradient ratio of the structure. The structure’s high-gradient performance, 105 MV/m at 250 ns pulse length and low breakdown rate, matches previously tested structures validating both CERN fabrication and the compact coupler design.

  4. CLIC accelerator modules under construction at CERN

    CERN Multimedia

    Anna Pantelia

    2012-01-01

    The Compact LInear Collider (CLIC) study is dedicated to the design of an electron-positron (e- e+) linear accelerator, colliding particle beams at the energy of 3 TeV. The CLIC required luminosity can be reached with powerful particle beams (14 MW each) colliding with extremely small dimensions and high beam stability at the interaction point. The accelerated particle beams must have dimensions of 45 nm in the horizontal plane and 1 nm in the vertical plane. CLIC relies upon a novel two-beam acceleration concept in which the Radio Frequency (RF) power is extracted from a low energy but high-intensity particle beam, called Drive Beam (DB), and transferred to a parallel high energy accelerating particle beam, called Main Beam (MB). The extraction and transfer of the RF power is achieved by the Power Extraction and Transfer Structures (PETS) and the particle beam acceleration is achieved with high precision RF-Accelerating Structures (AS), operating at 11.9942 GHz with an accelerating gradient of 100 MV/m, whi...

  5. CLIC Test Facility 3

    CERN Multimedia

    Kossyvakis, I; Faus-golfe, A

    2007-01-01

    The design of CLIC is based on a two-beam scheme, where short pulses of high power 30 GHz RF are extracted from a drive beam running parallel to the main beam. The 3rd generation CLIC Test Facility (CTF3) will demonstrate the generation of the drive beam with the appropriate time structure, the extraction of 30 GHz RF power from this beam, as well as acceleration of a probe beam with 30 GHz RF cavities. The project makes maximum use of existing equipment and infrastructure of the LPI complex, which became available after the closure of LEP.

  6. The CLIC Vertex Detector

    CERN Document Server

    Dannheim, D

    2015-01-01

    The precision physics needs at TeV-scale linear electron-positron colliders (ILC and CLIC) require a vertex-detector system with excellent flavour-tagging capabilities through a meas- urement of displaced vertices. This is essential, for example, for an explicit measurement of the Higgs decays to pairs of b-quarks, c-quarks and gluons. Efficient identification of top quarks in the decay t → W b will give access to the ttH-coupling measurement. In addition to those requirements driven by physics arguments, the CLIC bunch structure calls for hit tim- ing at the few-ns level. As a result, the CLIC vertex-detector system needs to have excellent spatial resolution, full geometrical coverage extending to low polar angles, extremely low material budget, low occupancy facilitated by time-tagging, and sufficient heat removal from sensors and readout. These considerations challenge current technological limits. A detector concept based on hybrid pixel-detector technology is under development for the CLIC ver- tex det...

  7. The CLIC Vertex Detector

    Science.gov (United States)

    Dannheim, D.

    2015-03-01

    The precision physics needs at TeV-scale linear electron-positron colliders (ILC and CLIC) require a vertex-detector system with excellent flavour-tagging capabilities through a measurement of displaced vertices. This is essential, for example, for an explicit measurement of the Higgs decays to pairs of b-quarks, c-quarks and gluons. Efficient identification of top quarks in the decay t → Wb will give access to the ttH-coupling measurement. In addition to those requirements driven by physics arguments, the CLIC bunch structure calls for hit timing at the few-ns level. As a result, the CLIC vertex-detector system needs to have excellent spatial resolution, full geometrical coverage extending to low polar angles, extremely low material budget, low occupancy facilitated by time-tagging, and sufficient heat removal from sensors and readout. These considerations challenge current technological limits. A detector concept based on hybrid pixel-detector technology is under development for the CLIC vertex detector. It comprises fast, low-power and small-pitch readout ASICs implemented in 65 nm CMOS technology (CLICpix) coupled to ultra-thin planar or active HV-CMOS sensors via low-mass interconnects. The power dissipation of the readout chips is reduced by means of power pulsing, allowing for a cooling system based on forced gas flow. This contribution reviews the requirements and design optimisation for the CLIC vertex detector and gives an overview of recent R&D achievements in the domains of sensors, readout and detector integration.

  8. The CLIC Vertex Detector

    International Nuclear Information System (INIS)

    The precision physics needs at TeV-scale linear electron-positron colliders (ILC and CLIC) require a vertex-detector system with excellent flavour-tagging capabilities through a measurement of displaced vertices. This is essential, for example, for an explicit measurement of the Higgs decays to pairs of b-quarks, c-quarks and gluons. Efficient identification of top quarks in the decay t → Wb will give access to the ttH-coupling measurement. In addition to those requirements driven by physics arguments, the CLIC bunch structure calls for hit timing at the few-ns level. As a result, the CLIC vertex-detector system needs to have excellent spatial resolution, full geometrical coverage extending to low polar angles, extremely low material budget, low occupancy facilitated by time-tagging, and sufficient heat removal from sensors and readout. These considerations challenge current technological limits. A detector concept based on hybrid pixel-detector technology is under development for the CLIC vertex detector. It comprises fast, low-power and small-pitch readout ASICs implemented in 65 nm CMOS technology (CLICpix) coupled to ultra-thin planar or active HV-CMOS sensors via low-mass interconnects. The power dissipation of the readout chips is reduced by means of power pulsing, allowing for a cooling system based on forced gas flow. This contribution reviews the requirements and design optimisation for the CLIC vertex detector and gives an overview of recent R and D achievements in the domains of sensors, readout and detector integration

  9. Collective effects and experimental verification of the CLIC drive beam and decelerator

    OpenAIRE

    2014-01-01

    The Compact Linear Collider (CLIC) is a potential next-generation particle collider, in which electrons and positrons collide at a center-of-mass energy of up to 3 TeV. In order to reach a high accelerating gradient and reduce the length of the machine, CLIC uses a novel two-beam scheme. Here, the acceleration energy for the main beam is provided by energy extraction from a secondary electron drive beam, by the use of Power Extraction and Transfer Structures (PETS). This Ph.D. thesis descr...

  10. CLIC Brochure

    CERN Multimedia

    De Melis, Cinzia

    2015-01-01

    After the discovery of the Higgs boson and with upgrades to higher energy and luminosity, the LHC is mapping the route of particle physics into the future. The next step in this journey of discovery could be a linear electron-positron collider, which would complement the LHC and allow high precision measurements of the Higgs boson, the top quark and electroweak processes in addition to possible new physics beyond the Standard Model. The Compact Linear Collider is under development by two worldwide collaborations, pushing the limits of particle acceleration and detection. Technological R&D, physics simulations and engineering studies must all come together to make CLIC a reality.

  11. Beam Position Monitoring at CLIC

    CERN Document Server

    Prochnow, J

    2003-01-01

    At the European Organisation for Nuclear Research CERN in Geneva, Switzerland the design of the Compact LInear Collider (CLIC) for high energy physics is studied. To achieve the envisaged high luminosity the quadrupole magnets and radio-frequency accelerating structures have to be actively aligned with micron precision and submicron resolution. This will be done using beam-based algorithms which rely on beam position information inside of quadrupoles and accelerating structures. After a general introduction to the CLIC study and the alignment algorithms, the concept of the interaction between beams and radio-frequency structures is given. In the next chapter beam measurements and simulations are described which were done to study the performance of cavity beam position monitors (BPM). A BPM design is presented which is compatible with the multi-bunch operation at CLIC and could be used to align the quadrupoles. The beam position inside the accelerating structures will be measured by using the structures thems...

  12. Technological challenges of CLIC

    CERN Document Server

    CERN. Geneva; Döbert, Steffen; Arnau-Izquierdo, G; Redaelli, Stefano; Mainaud, Helène; Lefèvre, Thibaut

    2006-01-01

    Future e+e- Linear Colliders offer the potential to explore new physics at the TeV scale and beyond to very high precision. While the International Linear Collider (ILC) scheme of a collider in the 0.5 - 1 TeV range enters the engineering design phase, the Compact Linear Collider (CLIC) study explores the technical feasibility of a collider capable of reaching into the multi-TeV energy domain. Key ingredients of the CLIC scheme are acceleration at high-frequency (30 GHz) and high-gradient (150 MV/m) in normal conducting structures and the use of the so-called Two Beam Acceleration concept, where a high-charge electron beam (drive beam) running parallel to the main beam is decelerated to provide the RF power to accelerate the main beam itself. A vigorous R&D effort is presently developed by the CLIC international collaboration to demonstrate its feasibility by 2010, when the first physics results from LHC should be available to guide the choice of the centre-of-mass energy better suited to explore the futu...

  13. Beam dynamics and wakefield suppression in interleaved damped and detuned structures for CLIC

    CERN Document Server

    D'Elia, A; Khan, V F; Jones, R M; Latina, A; Nesmiyan, I; Riddone, G

    2013-01-01

    Acceleration of multiple bunches of charged particles in the main linacs of the Compact Linear Collider (CLIC) with high accelerating fields provides two major challenges: firstly, to ensure the surface electromagnetic fields do not cause electrical breakdown and subsequent surface damage, and secondly, to ensure the beam-excited wakefields are sufficiently suppressed to avoid appreciable emittance dilution. In the baseline design for CLIC, heavy wakefield suppression is used (Q ~ 10) [1] and this ensures the beam quality is well-preserved [2]. Here we discuss an alternative means to suppress the wakefield which relies on strong detuning of the cell dipole frequencies, together with moderate damping, effected by manifolds which are slot-coupled to each accelerating cell. This damped and detuned wakefield suppression scheme is based on the methodology developed for the Japanese Linear Collider/Next Linear Collider (JLC/NLC) [3]. Here we track the multi-bunch beam down the complete collider, u...

  14. TCAD simulations of High-Voltage-CMOS Pixel structures for the CLIC vertex detector

    CERN Document Server

    Buckland, Matthew Daniel

    2016-01-01

    The requirements for precision physics and the experimental conditions at CLIC result in stringent constraints for the vertex detector. Capacitively coupled active pixel sensors with 25 μm pitch implemented in a commercial 180 nm High-Voltage CMOS (HV-CMOS) process are currently under study as a candidate technology for the CLIC vertex detector. Laboratory calibration measurements and beam tests with prototypes are complemented by detailed TCAD and electronic circuit simulations, aiming for a comprehensive understanding of the signal formation in the HV-CMOS sensors and subsequent readout stages. In this note 2D and 3D TCAD simulation results of the prototype sensor, the Capacitively Coupled Pixel Detector version three (CCPDv3), will be presented. These include the electric field distribution, leakage current, well capacitance, transient response to minimum ionising particles and charge-collection.

  15. Results from the CLIC X-BAND structure test program at the NLCTA

    CERN Document Server

    Adolphsen, Chris; Dolgashev, Valery; Laurent, Lisa; Tantawi, Sami; Wang, Faya; Wang, W Juwen; Doebert, Steffen; Grudiev, Alexej; Riddone, Germana; Wuensh, Walter; Zennaro, Riccardo; Higashi, Yasuo; Higo, Toshiyasu

    2010-01-01

    As part of a SLAC-CERN-KEK col­lab­o­ra­tion on high gra­di­ent X-band struc­ture re­search, sev­er­al pro­to­type struc­tures for the CLIC lin­ear col­lid­er study have been test­ed using two of the high power (300 MW) X-band rf sta­tions in the NLCTA fa­cil­i­ty at SLAC. These struc­tures dif­fer in terms of their man­u­fac­tur­ing (brazed disks and clamped quad­rants), gra­di­ent pro­file (amount by which the gra­di­ent in­creas­es along the struc­ture which op­ti­mizes ef­fi­cien­cy and max­i­mizes sus­tain­able gra­di­ent) and HOM damp­ing (use of slots or waveg­uides to rapid­ly dis­si­pate dipole mode en­er­gy). The CLIC goal in the next few years is to demon­strate the fea­si­bil­i­ty of a CLIC-ready base­line de­sign and to in­ves­ti­gate al­ter­na­tives which could bring even high­er ef­fi­cien­cy. This paper sum­ma­rizes the high gra­di­ent test re­sults from the NLCTA in sup­port of this ef­fort.

  16. CLIC PHYSICS OVERVIEW

    CERN Document Server

    Bozovic-Jelisavcic, Ivanka

    2016-01-01

    In this paper, based on the invited talk at the 17th Lomonosov Conference of Elementary Particle Physics, the physics program at the future Compact Linear Collider (CLIC) will be reviewed, with particular emphasis on the Higgs physics studies. It will be demonstrated, on the basis of detailed physics and detector studies carried out at CLIC, that the CLIC is indeed a precision tool for studies both in the Higgs sector and beyond the Standard Model.

  17. CLIC MDI Overview

    OpenAIRE

    Gatignon, Lau

    2012-01-01

    This paper gives an introduction to the layout of the CLIC Machine Detector Interface as it has been defined for the CLIC Conceptual Design Report. We concentrate on the specific case of the CLIC_SiD detector, although the push-pull concept for two detectors has been included in the design. Some recent work and developments are described as well. However, for the details we refer to the detailed technical talks at this conference.

  18. ACE3P Computations of Wakefield Coupling in the CLIC Two-Beam Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Candel, Arno; Li, Z.; Ng, C.; Rawat, V.; Schussman, G.; Ko, K.; /SLAC; Syratchev, I.; Grudiev, A.; Wuensch, W.; /CERN

    2010-10-27

    The Compact Linear Collider (CLIC) provides a path to a multi-TeV accelerator to explore the energy frontier of High Energy Physics. Its novel two-beam accelerator concept envisions rf power transfer to the accelerating structures from a separate high-current decelerator beam line consisting of power extraction and transfer structures (PETS). It is critical to numerically verify the fundamental and higher-order mode properties in and between the two beam lines with high accuracy and confidence. To solve these large-scale problems, SLAC's parallel finite element electromagnetic code suite ACE3P is employed. Using curvilinear conformal meshes and higher-order finite element vector basis functions, unprecedented accuracy and computational efficiency are achieved, enabling high-fidelity modeling of complex detuned structures such as the CLIC TD24 accelerating structure. In this paper, time-domain simulations of wakefield coupling effects in the combined system of PETS and the TD24 structures are presented. The results will help to identify potential issues and provide new insights on the design, leading to further improvements on the novel CLIC two-beam accelerator scheme.

  19. Preparing for CLIC tests

    CERN Multimedia

    Laurent Guiraud

    1999-01-01

    The Canon 5 undergoes first brazing for preparation in the CLIC study at the CLIC Test Facility 2 (CTF2). This will test injection for a proposed linear collider that will further explore discoveries made at the LHC. Electric fields in the canon will boost electrons into the acceleration fields of the collider.

  20. Beam position monitoring at CLIC

    OpenAIRE

    Prochnow, Jan Erik

    2003-01-01

    At the European Organisation for Nuclear Research CERN in Geneva, Switzerland the design of the Compact LInear Collider (CLIC) for high energy physics is studied. To achieve the envisaged high luminosity the quadrupole magnets and radio-frequency accelerating structures have to be actively aligned with micron precision and submicron resolution. This will be done using beam-based algorithms which rely on beam position information inside of quadrupoles and accelerating structures. After a gener...

  1. CLIC and CTF3

    CERN Document Server

    Tecker, F

    2008-01-01

    The CLIC study has been exploring the scheme for an electron-positron Collider (CLIC) with high luminosity (10$^{34}$ - 10$^{35}$ cm2/s) and a nominal centre-of-mass energy of 3 TeV in order to make the multi-TeV range accessible for physics. The CLIC Test Facility CTF3, built at CERN by an international collaboration, aims at demonstrating the feasibility of the CLIC scheme by 2010. CTF3 consists of a 150 MeV electron linac followed by a 42 m long delay loop and an 84 m combiner ring, followed by a two-beam test stand and a test decelerator. The linac and delay loop have been previously commissioned, while the combiner ring has been recently completed. After a presentation of the recent CLIC parameters, the status of the test facility, the experimental results achieved and the future plans will be presented.

  2. CLIC Status and Outlook

    CERN Document Server

    Stapnes, Stapnes

    2012-01-01

    The Compact Linear Collider study (CLIC) is in the process of completing a Conceptual Design Report (CDR) for a multi-TeV linear electron-positron collider. The CLICconcept is based on high gradient normal-conducting accelerating structures. The RF power for the acceleration of the colliding beams is produced by a novel two beam acceleration scheme, where power is extracted from a high current drive beam that runs parallel with the main linac. In order to establish the feasibility of this concept a number of key issues have been addressed. A short summary of the progress and status of the corresponding studies will be given, as well as an outline of the preparation and work towards an implementation plan by 2016.

  3. CLIC brochure (English version)

    CERN Multimedia

    Lefevre, Christiane

    2012-01-01

    The world's biggest and most powerful accelerator, the LHC, is mapping the route of particle physics for the future. The next step, to complement the LHC in exploring this new region, is most likely to be a linear electron-positron collider. The Compact Linear Collider (CLIC) is a novel approach to such a collider. It is currently under development by the CLIC collaboration, which is hosted at CERN.

  4. From glutathione transferase to pore in a CLIC

    CERN Document Server

    Cromer, B A; Morton, C J; Parker, M W; 10.1007/s00249-002-0219-1

    2002-01-01

    Many plasma membrane chloride channels have been cloned and characterized in great detail. In contrast, very little is known about intracellular chloride channels. Members of a novel class of such channels, called the CLICs (chloride intracellular channels), have been identified over the last few years. A striking feature of the CLIC family of ion channels is that they can exist in a water- soluble state as well as a membrane-bound state. A major step forward in understanding the functioning of these channels has been the recent crystal structure determination of one family member, CLIC1. The structure confirms that CLICs are members of the glutathione S- transferase superfamily and provides clues as to how CLICs can insert into membranes to form chloride channels. (69 refs).

  5. CLIC Muon Sweeper Design

    CERN Document Server

    Aloev, A; Gatignon, L; Modena, M; Pilicer, B; Tapan, I

    2016-01-01

    There are several background sources which may affect the analysis of data and detector performans at the CLIC project. One of the important background source is halo muons, which are generated along the beam delivery system (BDS), for the detector performance. In order to reduce muon background, magnetized muon sweepers have been used as a shielding material that is already described in a previous study for CLIC [1]. The realistic muon sweeper has been designed with OPERA. The design parameters of muon sweeper have also been used to estimate muon background reduction with BDSIM Monte Carlo simulation code [2, 3].

  6. The CLIC project and the design for an e+- collider

    International Nuclear Information System (INIS)

    The two-beam scheme of the CERN Linear Collider (CLIC) project is discussed. The problems in achieving the needed luminosity, caused by disruption and beam radiation are outlined. The main CLIC paramaters are presented. The supply of the RF power and problems of RF focusing caused by wakefield effects are discussed. The transfer and main LINAC structures, and the design of damping rings and the final focus are outlined. (H.W.). 25 refs.; 3 figs.; 2 tabs

  7. CERN: Making CLIC tick

    International Nuclear Information System (INIS)

    While the Large Hadron Collider (LHC) scheme for counter-rotating proton beams in a new superconducting ring to be built in CERN's existing 27-kilometre LEP tunnel is being pushed as the Laboratory's main construction project for the 1990s, research and development continues in parallel for an eventual complementary attack on new physics frontiers with CERN's Linear Collider - CLIC - firing TeV electron and positron beams at each other

  8. Brazing of Mo to a CuZr alloy for the production of bimetallic raw materials for the CLIC accelerating structures

    CERN Document Server

    Salvo, M; Heikkinen, Samuli; Salvo, Milena; Casalegno, Valentina; Sgobba, Stefano; Rizzo, Stefano; Izquierdo, Gonzalo Arnau; Taborelli, Mauro

    2010-01-01

    Future linear accelerators, as CLIC (Compact Linear Collider), are extremely demanding in terms of material properties. Traditionally accelerating structure is made of brazed OFE copper parts. For the high conducting regions submitted to mechanical fatigue, CuZr would represent an improved selection than pure copper while for regions where the highest electric field is applied a refractory metal, i.e. Mo, could result in a better performance. The feasibility of joining such materials, namely CuZr (UNS C15000) and pure Mo has been investigated. The joining method developed and investigated here consists in a vacuum brazing process exploiting a Cu-based brazing filler applied under appropriate vacuum conditions. Apparent shear strength (adapted from ASTM B898) on the joined samples was about 200 MPa. (C) 2010 Elsevier B.V. All rights reserved.

  9. Interaction of the chloride intracellular ion channel protein CLIC1 with different sterols in model membranes

    International Nuclear Information System (INIS)

    structural features of the membrane bound CLIC1 and CLIC1-Cholesterol complex in solution. Conclusion: These findings confirm that the GXXXG motif within CLIC1 acts as a sterol binding site facilitating the protein’s membrane interaction and insertion. Critical to this process of spontaneous membrane insertion is the presence of an intact 3β-OH group within the sterol structure itself. Furthermore, additional double bonds and methylation of the steroid skeleton enhanced CLIC1 membrane insertion.

  10. Interaction of Human Chloride Intracellular Channel Protein 1 (CLIC1) with Lipid Bilayers: A Fluorescence Study.

    Science.gov (United States)

    Hare, Joanna E; Goodchild, Sophia C; Breit, Samuel N; Curmi, Paul M G; Brown, Louise J

    2016-07-12

    Chloride intracellular channel protein 1 (CLIC1) is very unusual as it adopts a soluble glutathione S-transferase-like canonical fold but can also autoinsert into lipid bilayers to form an ion channel. The conversion between these forms involves a large, but reversible, structural rearrangement of the CLIC1 module. The only identified environmental triggers controlling the metamorphic transition of CLIC1 are pH and oxidation. Until now, there have been no high-resolution structural data available for the CLIC1 integral membrane state, and consequently, a limited understanding of how CLIC1 unfolds and refolds across the bilayer to form a membrane protein with ion channel activity exists. Here we show that fluorescence spectroscopy can be used to establish the interaction and position of CLIC1 in a lipid bilayer. Our method employs a fluorescence energy transfer (FRET) approach between CLIC1 and a dansyl-labeled lipid analogue to probe the CLIC1-lipid interface. Under oxidizing conditions, a strong FRET signal between the single tryptophan residue of CLIC1 (Trp35) and the dansyl-lipid analogue was detected. When considering the proportion of CLIC1 interacting with the lipid bilayer, as estimated by fluorescence quenching experiments, the FRET distance between Trp35 and the dansyl moiety on the membrane surface was determined to be ∼15 Å. This FRET-detected interaction provides direct structural evidence that CLIC1 associates with membranes. The results presented support the current model of an oxidation-driven interaction of CLIC1 with lipid bilayers and also propose a membrane anchoring role for Trp35. PMID:27299171

  11. Surface structure of oriented PET films

    CERN Document Server

    Kirov, K

    2001-01-01

    crystallinity and the level of molecular orientation of the polymer are highest at the film surface and gradually decrease away from it. The same trend for an increase in structural order nearer the film surface was observed in a series of PET films drawn uniaxially in laboratory conditions. The observed strong dependence of stratification in the oriented films on drawing ratio, lead to the conclusion, that the structural gradients arise as a result of viscous flow. The molecular mechanism of stratification is discussed and leads to the idea of enhanced chain mobility at the PET film surface. The idea is in line with recent studies showing a depression of the glass transition temperature of free polymer surfaces. In addition, the results on structure formation in PET films during drawing, give support to the existing view that polymer crystallisation is assisted by a spinodal-decomposition nucleation process. Polymer films are widely used as substrates in nano-composite materials and therefore have to possess...

  12. A Multi-TeV Linear Collider Based on CLIC Technology CLIC Conceptual Design Report

    CERN Document Server

    Burrows, P; Draper, M; Garvey, T; Lebrun, P; Peach, K; Phinney, N; Schmickler, H; Schulte, D; Toge, N

    2012-01-01

    This report describes the accelerator studies for a future multi-TeV e+e- collider based on the Compact Linear Collider (CLIC) technology. The CLIC concept as described in the report is based on high gradient normal-conducting accelerating structures where the RF power for the acceleration of the colliding beams is extracted from a high-current Drive Beam that runs parallel with the main linac. The focus of CLIC R&D over the last years has been on addressing a set of key feasibility issues that are essential for proving the fundamental validity of the CLIC concept. The status of these feasibility studies are described and summarized. The report also includes a technical description of the accelerator components and R&D to develop the most important parts and methods, as well as a description of the civil engineering and technical services associated with the installation. Several larger system tests have been performed to validate the two-beam scheme, and of particular importance are the results from ...

  13. CLIC Physics Overview

    CERN Document Server

    AUTHOR|(SzGeCERN)471575

    2016-01-01

    This paper, based on the invited talk given at the 17th Lomonosov Conference of Elementary Particle Physics, summarizes the physics program at CLIC, with particular emphasis on the Higgs physics studies. The physics reach of CLIC operating in three energy stages, at 350 GeV, 1.4 TeV and 3 TeV center-of-mass energies is reviewed. The energy-staged approach is motivated by the high-precision physics measurements in the Higgs and top sector as well as by direct and indirect searches for beyond the Standard Model physics. The first stage, at or above 350 GeV, gives access to precision Higgs physics through the Higgsstrahlung and WW-fusion production processes, providing absolute values of the Higgs couplings to fermions and bosons. This stage also addresses precision top physics around the top-pair-production threshold. The second stage, at 1.4 TeV, opens the energy frontier, allowing for the discovery of new physics phenomena. This stage also gives access to additional Higgs properties, such as the top-Yukawa co...

  14. Status of Wakefield Monitor Experiments at the CLIC Test Facility

    CERN Document Server

    Lillestøl, Reidar; Aftab, Namra; Corsini, Roberto; Döbert, Steffen; Farabolini, Wilfrid; Grudiev, Alexej; Javeed, Sumera; Pfingstner, Juergen; Wuensch, Walter

    2016-01-01

    For the very low emittance beams in CLIC, it is vital to mitigate emittance growth which leads to reduced luminosity in the detectors. One factor that leads to emittance growth is transverse wakefields in the accelerating structures. In order to combat this the structures must be aligned with a precision of a few um. For achieving this tolerance, accelerating structures are equipped with wakefield monitors that measure higher-order dipole modes excited by the beam when offset from the structure axis. We report on such measurements, performed using prototype CLIC accelerating structures which are part of the module installed in the CLIC Test Facility 3 (CTF3) at CERN. Measurements with and without the drive beam that feeds rf power to the structures are compared. Improvements to the experimental setup are discussed, and finally remaining measurements that should be performed before the completion of the program are summarized.

  15. CLIC CDR - physics and detectors: CLIC conceptual design report

    International Nuclear Information System (INIS)

    This report forms part of the Conceptual Design Report (CDR) of the Compact LInear Collider (CLIC). The CLIC accelerator complex is described in a separate CDR volume. A third document, to appear later, will assess strategic scenarios for building and operating CLIC in successive center-of-mass energy stages. It is anticipated that CLIC will commence with operation at a few hundred GeV, giving access to precision standard-model physics like Higgs and top-quark physics. Then, depending on the physics landscape, CLIC operation would be staged in a few steps ultimately reaching the maximum 3 TeV center-of-mass energy. Such a scenario would maximize the physics potential of CLIC providing new physics discovery potential over a wide range of energies and the ability to make precision measurements of possible new states previously discovered at the Large Hadron Collider (LHC). The main purpose of this document is to address the physics potential of a future multi-TeV e+e- collider based on CLIC technology and to describe the essential features of a detector that are required to deliver the full physics potential of this machine. The experimental conditions at CLIC are significantly more challenging than those at previous electron-positron colliders due to the much higher levels of beam-induced backgrounds and the 0.5 ns bunch-spacing. Consequently, a large part of this report is devoted to understanding the impact of the machine environment on the detector with the aim of demonstrating, with the example of realistic detector concepts, that high precision physics measurements can be made at CLIC. Since the impact of background increases with energy, this document concentrates on the detector requirements and physics measurements at the highest CLIC center-of-mass energy of 3 TeV. One essential output of this report is the clear demonstration that a wide range of high precision physics measurements can be made at CLIC with detectors which are challenging, but considered

  16. CLIC CDR - physics and detectors: CLIC conceptual design report.

    Energy Technology Data Exchange (ETDEWEB)

    Berger, E.; Demarteau, M.; Repond, J.; Xia, L.; Weerts, H. (High Energy Physics); (Many)

    2012-02-10

    This report forms part of the Conceptual Design Report (CDR) of the Compact LInear Collider (CLIC). The CLIC accelerator complex is described in a separate CDR volume. A third document, to appear later, will assess strategic scenarios for building and operating CLIC in successive center-of-mass energy stages. It is anticipated that CLIC will commence with operation at a few hundred GeV, giving access to precision standard-model physics like Higgs and top-quark physics. Then, depending on the physics landscape, CLIC operation would be staged in a few steps ultimately reaching the maximum 3 TeV center-of-mass energy. Such a scenario would maximize the physics potential of CLIC providing new physics discovery potential over a wide range of energies and the ability to make precision measurements of possible new states previously discovered at the Large Hadron Collider (LHC). The main purpose of this document is to address the physics potential of a future multi-TeV e{sup +}e{sup -} collider based on CLIC technology and to describe the essential features of a detector that are required to deliver the full physics potential of this machine. The experimental conditions at CLIC are significantly more challenging than those at previous electron-positron colliders due to the much higher levels of beam-induced backgrounds and the 0.5 ns bunch-spacing. Consequently, a large part of this report is devoted to understanding the impact of the machine environment on the detector with the aim of demonstrating, with the example of realistic detector concepts, that high precision physics measurements can be made at CLIC. Since the impact of background increases with energy, this document concentrates on the detector requirements and physics measurements at the highest CLIC center-of-mass energy of 3 TeV. One essential output of this report is the clear demonstration that a wide range of high precision physics measurements can be made at CLIC with detectors which are challenging, but

  17. Numerical Verification of the Power Transfer and Wakefield Coupling in the Clic Two-Beam Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Candel, Arno; Li, Z.; Ng, C.; Rawat, V.; Schussman, G.; Ko, K.; /SLAC; Syratchev, I.; Grudiev, A.; Wuensch, W.; /CERN

    2011-08-19

    The Compact Linear Collider (CLIC) provides a path to a multi-TeV accelerator to explore the energy frontier of High Energy Physics. Its two-beam accelerator (TBA) concept envisions complex 3D structures, which must be modeled to high accuracy so that simulation results can be directly used to prepare CAD drawings for machining. The required simulations include not only the fundamental mode properties of the accelerating structures but also the Power Extraction and Transfer Structure (PETS), as well as the coupling between the two systems. Time-domain simulations will be performed to understand pulse formation, wakefield damping, fundamental power transfer and wakefield coupling in these structures. Applying SLAC's parallel finite element code suite, these large-scale problems will be solved on some of the largest supercomputers available. The results will help to identify potential issues and provide new insights on the design, leading to further improvements on the novel two-beam accelerator scheme.

  18. Academic Training - Technological challenges of CLIC

    CERN Multimedia

    Françoise Benz

    2006-01-01

    2005-2006 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 12, 13, 14, 15 and 16 June 11:00-12:00 - Auditorium, bldg 500 Technological challenges of CLIC R. Corsini, S. Doebert, S. Redaelli, T.Lefevre, CERN-AB and G. Arnau Izquierdo, H. Mainaud, CERN-TS Future e+e- Linear Colliders offer the potential to explore new physics at the TeV scale and beyond to very high precision. While the International Linear Collider (ILC) scheme of a collider in the 0.5 - 1 TeV range enters the engineering design phase, the Compact Linear Collider (CLIC) study explores the technical feasibility of a collider capable of reaching into the multi-TeV energy domain. Key ingredients of the CLIC scheme are acceleration at high-frequency (30 GHz) and high-gradient (150 MV/m) in normal conducting structures and the use of the so-called Two Beam Acceleration concept, where a high-charge electron beam (drive beam) running parallel to the main beam is decelerated to provide the RF power to accelerate the main beam itself. A vigorous R&...

  19. The CLIC Physics Potential

    CERN Document Server

    Robson, Aidan

    2016-01-01

    The physics and detector studies for the Compact Linear Collider (CLIC) are introduced. A staged programme of $e^{+}e^{−}$ collisions covering $\\sqrt{s}$ = 380 GeV, 1.5 TeV, and 3 TeV would allow precise measurements of Higgs boson couplings, in many cases to the percent level. This corresponds to precision higher than that expected for the high-luminosity Large Hadron Collider. Such precise Higgs coupling measurements would allow sensitivity to a variety of new physics models and the ability to distinguish between them. In addition, new particles directly produced in pairs could be measured with great precision, and measurements in the top-quark sector would provide sensitivity to new physics effects at the scales of tens of TeV.

  20. Beam instability induced by rf deflectors in the combiner ring of the CLIC test facility and mitigation by damped deflecting structures

    CERN Document Server

    Alesini, D; Biscari, C; Ghigo, A; Corsini, R

    2011-01-01

    In the CTF3 (CLIC test facility 3) run of November 2007, a vertical beam instability has been found in the combiner ring during operation. After a careful analysis, the source of the instability has been identified in the vertical deflecting modes trapped in the rf deflectors and excited by the beam passage. A dedicated tracking code that includes the induced transverse wakefield and the multibunch multipassage effects has been written and the results of the beam dynamics analysis are presented in the paper. The mechanism of the instability was similar to the beam breakup in a linear accelerator or in an energy recovery linac. The results of the code allowed identifying the main key parameters driving such instability and allowed finding the main knobs to mitigate it. To completely suppress such beam instability, two new rf deflectors have been designed, constructed, and installed in the ring. In the new structures the frequency separation between the vertical and horizontal deflecting modes has been increase...

  1. Spectrometers for RF breakdown studies for CLIC

    Science.gov (United States)

    Jacewicz, M.; Ziemann, V.; Ekelöf, T.; Dubrovskiy, A.; Ruber, R.

    2016-08-01

    An e+e- collider of several TeV energy will be needed for the precision studies of any new physics discovered at the LHC collider at CERN. One promising candidate is CLIC, a linear collider which is based on a two-beam acceleration scheme that efficiently solves the problem of power distribution to the acceleration structures. The phenomenon that currently prevents achieving high accelerating gradients in high energy accelerators such as the CLIC is the electrical breakdown at very high electrical field. The ongoing experimental work within the CLIC collaboration is trying to benchmark the theoretical models focusing on the physics of vacuum breakdown which is responsible for the discharges. In order to validate the feasibility of accelerating structures and observe the characteristics of the vacuum discharges and their eroding effects on the structure two dedicated spectrometers are now commissioned at the high-power test-stands at CERN. First, the so called Flashbox has opened up a possibility for non-invasive studies of the emitted breakdown currents during two-beam acceleration experiments. It gives a unique possibility to measure the energy of electrons and ions in combination with the arrival time spectra and to put that in context with accelerated beam, which is not possible at any of the other existing test-stands. The second instrument, a spectrometer for detection of the dark and breakdown currents, is operated at one of the 12 GHz stand-alone test-stands at CERN. Built for high repetition rate operation it can measure the spatial and energy distributions of the electrons emitted from the acceleration structure during a single RF pulse. Two new analysis tools: discharge impedance tracking and tomographic image reconstruction, applied to the data from the spectrometer make possible for the first time to obtain the location of the breakdown inside the structure both in the transversal and longitudinal direction thus giving a more complete picture of the

  2. DC Breakdown experiments for CLIC

    CERN Document Server

    Descoeudres, A; Taborelli, M

    2008-01-01

    For the production of the Compact Linear Collider (CLIC) RF accelerating structures, a material capable of sustaining high electric field, with a low breakdown rate and showing low damages after breakdowns is needed. A DC breakdown study is underway at CERN in order to test candidate materials and surface preparations. The saturated breakdown fields of several metals and alloys have been measured, ranging from 100 MV/m for Al to 850 MV/m for stainless steel, being around 170 MV/m for Cu and 430 MV/m for Mo for example. The conditioning speed of Mo can be significantly improved by removing oxides at the surface with a vacuum heat treatment, typically at 875±C for 2 hours. DC breakdown rate measurements have been done with Cu and Mo electrodes, showing similar results as in RF experiments: the breakdown probability seems to exponentially increase with the applied field. Measurements of time delays before breakdown show two different populations of breakdowns, immediate and delayed breakdowns, indicating that t...

  3. The CERN study of a 2 TeV e+e- collider CLIC

    International Nuclear Information System (INIS)

    Progress with the CERN study of a 2 TeV e+e- linear collider (CLIC) is reported. The CLIC Test Facility for drive beam generation is giving first results. Results are also reported from development work on 30 GHz prototype accelerating structures (including RF quadrupole configurations) from a 30 GHz transfer structure for RF power generation in the CLIC two-beam scheme, from a prototype system for submicron automatic alignment and from theoretical work on wake-field stabilization, alignment tolerances, compensation of the beams energy spread and the final focus system

  4. Cholesterol Promotes Interaction of the Protein CLIC1 with Phospholipid Monolayers at the Air–Water Interface

    Directory of Open Access Journals (Sweden)

    Khondker R. Hossain

    2016-02-01

    Full Text Available CLIC1 is a Chloride Intracellular Ion Channel protein that exists either in a soluble state in the cytoplasm or as a membrane bound protein. Members of the CLIC family are largely soluble proteins that possess the intriguing property of spontaneous insertion into phospholipid bilayers to form integral membrane ion channels. The regulatory role of cholesterol in the ion-channel activity of CLIC1 in tethered lipid bilayers was previously assessed using impedance spectroscopy. Here we extend this investigation by evaluating the influence of cholesterol on the spontaneous membrane insertion of CLIC1 into Langmuir film monolayers prepared using 1-palmitoyl-2-oleoylphosphatidylcholine, 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-ethanolamine and 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-L-serine alone or in combination with cholesterol. The spontaneous membrane insertion of CLIC1 was shown to be dependent on the presence of cholesterol in the membrane. Furthermore, pre-incubation of CLIC1 with cholesterol prior to its addition to the Langmuir film, showed no membrane insertion even in monolayers containing cholesterol, suggesting the formation of a CLIC1-cholesterol pre-complex. Our results therefore suggest that CLIC1 membrane interaction involves CLIC1 binding to cholesterol located in the membrane for its initial docking followed by insertion. Subsequent structural rearrangements of the protein would likely also be required along with oligomerisation to form functional ion channels.

  5. Cholesterol Promotes Interaction of the Protein CLIC1 with Phospholipid Monolayers at the Air–Water Interface

    Science.gov (United States)

    Hossain, Khondker R.; Al Khamici, Heba; Holt, Stephen A.; Valenzuela, Stella M.

    2016-01-01

    CLIC1 is a Chloride Intracellular Ion Channel protein that exists either in a soluble state in the cytoplasm or as a membrane bound protein. Members of the CLIC family are largely soluble proteins that possess the intriguing property of spontaneous insertion into phospholipid bilayers to form integral membrane ion channels. The regulatory role of cholesterol in the ion-channel activity of CLIC1 in tethered lipid bilayers was previously assessed using impedance spectroscopy. Here we extend this investigation by evaluating the influence of cholesterol on the spontaneous membrane insertion of CLIC1 into Langmuir film monolayers prepared using 1-palmitoyl-2-oleoylphosphatidylcholine, 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-ethanolamine and 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-L-serine alone or in combination with cholesterol. The spontaneous membrane insertion of CLIC1 was shown to be dependent on the presence of cholesterol in the membrane. Furthermore, pre-incubation of CLIC1 with cholesterol prior to its addition to the Langmuir film, showed no membrane insertion even in monolayers containing cholesterol, suggesting the formation of a CLIC1-cholesterol pre-complex. Our results therefore suggest that CLIC1 membrane interaction involves CLIC1 binding to cholesterol located in the membrane for its initial docking followed by insertion. Subsequent structural rearrangements of the protein would likely also be required along with oligomerisation to form functional ion channels. PMID:26875987

  6. A 12 GHZ RF Power source for the CLIC study

    CERN Document Server

    Peauger, F; Curt, S; Doebert, S; McMonagle, G; Rossat, G; Schirm, KM; Syratchev, I; Timeo, L; Kuzikhov, S; Vikharev, AA; Haase, A; Sprehn, D; Jensen, A; Jongewaard, EN; Nantista, CD; Vlieks, A

    2010-01-01

    The CLIC RF frequency has been changed in 2008 from the initial 30 GHz to the European X-band 11.9942 GHz permitting beam independent power production using klystrons for CLIC accelerating structure testing. A design and fabrication contract for five klystrons at that frequency has been signed by different parties with SLAC. France (IRFU, CEA Saclay) is contributing a solid state modulator purchased in industry and specific 12 GHz RF network components to the CLIC study. RF pulses over 120 MW peak at 230 ns length will be obtained by using a novel SLED-I type pulse compression scheme designed and fabricated by IAP, Nizhny Novgorod, Russia. The X-band power test stand is being installed in the CLIC Test Facility CTF3 for independent structure and component testing in a bunker, but allowing, in a later stage, for powering RF components in the CTF3 beam lines. The design of the facility, results from commissioning of the RF power source and the expected performance of the Test Facility are reported.

  7. CLIC expands to include the Southern Hemisphere

    CERN Multimedia

    Roberto Cantoni

    2010-01-01

    Australia has recently joined the CLIC collaboration: the enlargement will bring new expertise and resources to the project, and is especially welcome in the wake of CERN budget redistributions following the recent adoption of the Medium Term Plan.   The countries involved in CLIC collaboration With the signing of a Memorandum of Understanding on 26 August 2010, the ACAS network (Australian Collaboration for Accelerator Science) became the 40th member of in the multilateral CLIC collaboration making Australia the 22nd country to join the collaboration. “The new MoU was signed by the ACAS network, which includes the Australian Synchrotron and the University of Melbourne”, explains Jean-Pierre Delahaye, CLIC Study Leader. “Thanks to their expertise, the Australian institutes will contribute greatly to the CLIC damping rings and the two-beam test modules." Institutes from any country wishing to join the CLIC collaboration are invited to assume responsibility o...

  8. CLIC vertex detector R&D

    Science.gov (United States)

    Alipour Tehrani, Niloufar

    2016-07-01

    A vertex detector concept is under development for the proposed multi-TeV linear e+e- Compact Linear Collider (CLIC). To perform precision physics measurements in a challenging environment, the CLIC vertex detector pushes the technological requirements to the limits. This paper reviews the requirements for the CLIC vertex detector and gives an overview of recent R&D achievements in the domains of sensor, readout, powering and cooling.

  9. Studies on the thermo-mechanical behavior of the CLIC two-beam module

    CERN Document Server

    Nousiainen, R; Österberg, K

    2010-01-01

    To fulfil the mechanical requirements set by the luminosity goals of the CLIC collider, currently under study, the 2-m two-beam modules, the shortest repetitive elements in the main linac, have to be controlled at micrometer level. At the same time these modules are exposed to variable high power dissipation while the accelerator is ramped up to nominal power as well as when the mode of CLIC operation is varied. This will result into inevitable temperature excursions driving mechanical distortions in and between different module components. A FEM model is essential to estimate and simulate the fundamental thermo-mechanical behaviour of the CLIC two-beam module to facilitate its design and development. In this paper, the fundamental thermal environments for the RF-components of the module are described. Also the thermal and structural results for the studied module configuration are presented showing the fundamental thermo-mechanical behaviour under the main CLIC collider operation conditions.

  10. Experimental Program for the CLIC test facility 3 test beam line

    CERN Document Server

    Adli, E; Dobert, S; Olvegaard, M; Schulte, D; Syratchev, I; Lillestol, Reidar

    2010-01-01

    The CLIC Test Facility 3 Test Beam Line is the first prototype for the CLIC drive beam decelerator. Stable transport of the drive beam under deceleration is a mandatory component in the CLIC two-beam scheme. In the Test Beam Line more than 50% of the total energy will be extracted from a 150 MeV, 28 A electron drive beam, by the use of 16 power extraction and transfer structures. A number of experiments are foreseen to investigate the drive beam characteristics under deceleration in the Test Beam Line, including beam stability, beam blow up and the efficiency of the power extraction. General benchmarking of decelerator simulation and theory studies will also be performed. Specially designed instrumentation including precision BPMs, loss monitors and a time-resolved spectrometer dump will be used for the experiments. This paper describes the experimental program foreseen for the Test Beam Line, including the relevance of the results for the CLIC decelerator studies.

  11. Tissue and subcellular distribution of CLIC1

    Directory of Open Access Journals (Sweden)

    Edwards John C

    2007-02-01

    Full Text Available Abstract Background CLIC1 is a chloride channel whose cellular role remains uncertain. The distribution of CLIC1 in normal tissues is largely unknown and conflicting data have been reported regarding the cellular membrane fraction in which CLIC1 resides. Results New antisera to CLIC1 were generated and were found to be sensitive and specific for detecting this protein. These antisera were used to investigate the distribution of CLIC1 in mouse tissue sections and three cultured cell lines. We find CLIC1 is expressed in the apical domains of several simple columnar epithelia including glandular stomach, small intestine, colon, bile ducts, pancreatic ducts, airway, and the tail of the epididymis, in addition to the previously reported renal proximal tubule. CLIC1 is expressed in a non-polarized distribution in the basal epithelial cell layer of the stratified squamous epithelium of the upper gastrointesitinal tract and the basal cells of the epididymis, and is present diffusely in skeletal muscle. Distribution of CLIC1 was examined in Panc1 cells, a relatively undifferentiated, non-polarized human cell line derived from pancreatic cancer, and T84 cells, a human colon cancer cell line which can form a polarized epithelium that is capable of regulated chloride transport. Digitonin extraction was used to distinguish membrane-inserted CLIC1 from the soluble cytoplasmic form of the protein. We find that digitonin-resistant CLIC1 is primarily present in the plasma membrane of Panc1 cells. In T84 cells, we find digitonin-resistant CLIC1 is present in an intracellular compartment which is concentrated immediately below the apical plasma membrane and the extent of apical polarization is enhanced with forskolin, which activates transepithelial chloride transport and apical membrane traffic in these cells. The sub-apical CLIC1 compartment was further characterized in a well-differentiated mouse renal proximal tubule cell line. The distribution of CLIC1 was

  12. Overview of the CLIC beam instrumentation

    CERN Document Server

    Lefèvre, T

    2011-01-01

    The performances of the Compact Linear Collider (CLIC) would rely on extremely tight tolerances on most beam parameters. The requirements for the CLIC beam instrumentation have been reviewed and studied in detail for the whole accelerator complex. In the context of the completion of the CLIC Conceptual Design Report, a first attempt was made to propose a technical solution for every CLIC instruments. Even if these choices were based on most recent technological achievements, whenever possible, alternatives solutions focusing on potential improvements on performance, reliability or cost minimization are proposed and will be studied in the future. This paper presents an overview of the CLIC beam instruments, gives a status of their already achieved performances and presents the future work activities.

  13. PET

    DEFF Research Database (Denmark)

    Mariager, Rasmus Mølgaard; Schmidt, Regin; Heiberg, Morten Rievers

    PET handler om den hemmelige tjenestes arbejde under den kolde krig 1945-1989. Her fortæller Regin Schmidt, Rasmus Mariager og Morten Heiberg om de mest dramatiske og interessante sager fra PET's arkiv. PET er på flere måder en udemokratisk institution, der er sat til at vogte over demokratiet....... Dens virksomhed er skjult for offentligheden, den overvåger borgernes aktiviteter, og den registrerer følsomme personoplysninger. Historien om PET rejser spørgsmålet om, hvad man skal gøre, når befolkningen i et demokrati er kritisk indstillet over for overvågningen af lovlige politiske aktiviteter......, mens myndighederne mener, at det er nødvendigt for at beskytte demokratiet. PET er på en gang en fortælling om konkrete aktioner og begivenheder i PET's arbejde og et stykke Danmarkshistorie. Det handler om overvågning, spioner, politisk ekstremisme og international terrorisme.  ...

  14. Simulations for CLIC Drive Beam Linac

    CERN Document Server

    Aksoy, Avni

    2012-01-01

    The Drive Beam Linac of the Compact Linear Collider (CLIC) has to accelerate an electron beam with 4.2 A up to 2.4 GeV in almost fully-loaded structures. The pulse contains about 70000 bunches, one in every second rf bucket, and has a length of 140 $\\mu$s. The beam stability along the beamline is of concern for such a high current and pulse length. We present different options for the lattice of the linac based on FODO, triplet and doublet cells and compare the transverse instability for each lattice including the effects of beam jitter, alignment and beam-based correction. Additionally longitudinal stability is discussed for different bunch compressors using FODO type of lattice.

  15. Precision Higgs boson measurement at CLIC

    CERN Document Server

    Pandurovic, Mila

    2016-01-01

    The design of the next generation collider in high energy physics will primarily focus on the possibility to achieve high precision of the measurements of interest. The necessary precision limits are set, in the first place, by the measurement of the Higgs boson but also by measurements that are sensitive to signs of New Physics. The Compact Linear Collider (CLIC) is an attractive option for a future multi-TeV linear electron-positron collider, with the potential to cover a rich physics program with high precision. In this lecture the CLIC accelerator, detector and backgrounds will be presented with emphesis on the capabilities of CLIC for precision Higgs physics.

  16. CLIC's three-step plan

    CERN Multimedia

    Katarina Anthony

    2012-01-01

    In early October, the Compact Linear Collider (CLIC) collaboration published its final Conceptual Design Report. Accompanying it was a strategic summary document that describes a whole new approach to the project: developing the linear e+e− collider in three energy stages. Though CLIC’s future still depends on signs from the LHC, its new staged approach to high-energy electron-positron physics for the post-LHC era is nothing short of convincing.   Instead of asking for a 48-kilometre-long commitment right off the bat, the CLIC collaboration is now presenting an accelerator that can be constructed in stages. For example, it could begin as an 11-kilometre 500 GeV accelerator that could later be extended to a 27-kilometre 1.5 TeV machine. Finally, after a decade or so of data taking, it could be taken up to the full 48-kilometre 3 TeV facility (see image 2). “Not only is the approach technically and financially practical, it also offers a very convincing physics prog...

  17. Manufacturing and Testing of a TBL PETS Prototype

    CERN Document Server

    Toral, Fernando; Calero, Jesus; Carrillo, David; De Aragon, Fernando; Garcia-Tabares, Luis; Gutierrez, Jose Luis; Lara, Alvaro; Rodriguez Garcia, Enrique; Sanchez, Laura; Dobert, Steffen; Syratchev, Igor

    2010-01-01

    The goal of the present CLIC Test Facility (CTF3) is to demonstrate the technical feasibility of the CLIC scheme. The Test Beam Line (TBL) is used to study a CLIC decelerator focusing on 12 GHz power production and the stability of the decelerated beam. The extracted CTF3 drive beam from the Combiner Ring (CR) features a maximum intensity of 28 A and 140 ns pulse duration, where the Test Beam Line consists of 16 cells, each one including a BPM, a quadrupole on top of a micrometeraccuracy mover and a RF power extractor so-called PETS (Power Extraction and Transfer Structure). This paper describes the first prototype fabrication techniques, with particular attention to the production of the long copper rods which induce the RF generation. A special test bench for the characterization of the device with low RF power measurements has been developed. Performed measurements of the scattering parameters and the electric field profile along the structure are carefully described. Finally, the prototype has been instal...

  18. Database and data structure for the novel TOF-PET detector developed for J-PET project

    CERN Document Server

    Czerwiński, E; Bednarski, T; Białas, P; Kapłon, Ł; Kochanowski, A; Korcyl, G; Kowal, J; Kowalski, P; Kozik, T; Krzemień, W; Kubicz, E; Molenda, M; Moskal, P; Niedźwiecki, Sz; Pałka, M; Pawlik, M; Raczyński, L; Rudy, Z; Salabura, P; Sharma, N G; Silarski, M; Słomski, A; Smyrski, J; Strzelecki, A; Wieczorek, A; Wiślicki, W; Zoń, N

    2014-01-01

    The complexity of the hardware and the amount of data collected during the PET imaging process require application of modern methods of efficient data organization and processing. In this article we will discuss the data structures and the flow of collected data from the novel TOF-PET medical scanner which is being developed at the Jagiellonian University. The developed data format reflects: registration process of the gamma quanta emitted from positron-electron annihilation, Front-End Electronic (FEE) structure and required input information for the image reconstruction. In addition, the system database fulfills possible demands of the evolving J-PET project.

  19. LHC and CLIC LLRF final reports

    CERN Document Server

    Dexter, A; Woolley, B; Ambattu, P; Tahir, I; Syratchev, Igor; Wuensch, Walter

    2013-01-01

    Crab cavities rotate bunches from opposing beams to achieve effective head-on collision in CLIC or collisions at an adjustable angle in LHC. Without crab cavities 90% of achievable luminosity at CLIC would be lost. In the LHC, the crab cavities allow the same or larger integrated luminosity while reducing significantly the requested dynamic range of physics detectors. The focus for CLIC is accurate phase synchronisation of the cavities, adequate damping of wakefields and modest amplitude stability. For the LHC, the main LLRF issues are related to imperfections: beam offsets in cavities, RF noise, measurement noise in feedback loops, failure modes and mitigations. This report develops issues associated with synchronising the CLIC cavities. It defines an RF system and experiments to validate the approach. It reports on the development of hardware for measuring the phase performance of the RF distributions system and cavities. For the LHC, the hardware being very close to the existing LLRF, the report focuses on...

  20. CLIC CTF3 for open days

    CERN Multimedia

    CLIC

    2013-01-01

    CLIC – the Compact Linear Collider – is a study for a future accelerator that reaches unprecedented energies for electrons and their antimatter twins, positrons. It uses a novel two-beam acceleration scheme in which the electrons and positrons are propelled to high energy by an additional high current electron beam, the so-called Drive Beam. In order to generate this high current Drive Beam, a long train of electron bunches is accelerated, parts of the train delayed in a Delay Loop and Combiner Rings, and interleaved by transversely deflecting radio-frequency cavities. The CLIC Test Facility CTF3, which is shown in the movie, examines the new technologies envisioned by the CLIC design, in particular the Drive Beam generation and the two-beam acceleration. It is a scaled-down version of the CLIC facility, and it has demonstrated the feasibility of the novel scheme.

  1. CLIC CTF3 for open days

    CERN Multimedia

    2013-01-01

    (subt french) CLIC – the Compact Linear Collider – is a study for a future accelerator that reaches unprecedented energies for electrons and their antimatter twins, positrons. It uses a novel two-beam acceleration scheme in which the electrons and positrons are propelled to high energy by an additional high current electron beam, the so-called Drive Beam. In order to generate this high current Drive Beam, a long train of electron bunches is accelerated, parts of the train delayed in a Delay Loop and Combiner Rings, and interleaved by transversely deflecting radio-frequency cavities. The CLIC Test Facility CTF3, which is shown in the movie, examines the new technologies envisioned by the CLIC design, in particular the Drive Beam generation and the two-beam acceleration. It is a scaled-down version of the CLIC facility, and it has demonstrated the feasibility of the novel scheme.

  2. Acquisition system for the CLIC Module

    CERN Document Server

    Vilalte, Sebastien

    2011-01-01

    The status of R&D activities for CLIC module acquisition are discussed [1]. LAPP is involved in the design of the local CLIC module acquisition crate, described in the document Study of the CLIC Module Front-End Acquisition and Evaluation Electronics [2]. This acquisition system is a project based on a local crate, assigned to the CLIC module, including several mother boards. These motherboards are foreseen to hold mezzanines dedicated to the different subsystems. This system has to work in radiation environment. LAPP is involved in the development of Drive Beam stripline position monitors read-out, described in the document Drive Beam Stripline BPM Electronics and Acquisition [3]. LAPP also develops a generic acquisition mezzanine that allows to perform all-around acquisition and components tests for drive beam stripline BPM read-out.

  3. Detector Optimization of the CLIC Tracker

    CERN Document Server

    Saxe, Gandalf

    2015-01-01

    CLIC (Compact Linear Collider) is a proposed high-energy electron-positron collider at CERN [1] that, if approved, will be built at the feet of the Jura Mountains in Switzerland, passing through CERN. As opposed to hadrons, electrons (e-) and positrons (e+) are elementary particles. Therefore, e-e+ collisions give a well defined initial state which allows high precision studies. A circular collider is not a viable option when going to high energies (several TeV) for a e-e+ collider due to synchrotron radiation. Therefore CLIC is designed as a linear collider. CLIC is proposed to be build in three center-of-mass energy stages: 380 GeV, 1.4 TeV and 3.0 TeV. The CLIC physics program includes the high precision measurements of the Higgs and top properties, the observation of rare processes, and the possible discovery of new particles [3].

  4. Successful start for new CLIC test facility

    CERN Multimedia

    2004-01-01

    A new test facility is being built to study key feasibility issues for a possible future linear collider called CLIC. Commissioning of the first part of the facility began in June 2003 and nominal beam parameters have been achieved already.

  5. Golden Jubilee Photos: A CLIC for the future

    CERN Multimedia

    2004-01-01

    http://www.cern.ch/cern50/ Prototype copper accelerating structures for CLIC. New accelerator projects take many years to make and mature. When the LHC project was still only a twinkle in CERN's eye, research was already starting on a new machine. A small team at CERN was setting about the task of studying a high-energy, compact, lepton linear collider, known as CLIC. This is possibly set to become the collider of the future. A machine of this kind has all the advantages of a collider (the total collision energy is equal to the sum of the energies of the two colliding beams) without the drawback of synchrotron radiation, which is produced when particles are accelerated around a ring and thus puts a limit on the energy of such colliders. But in a project as technically challenging as CLIC, considerable technological hurdles must be overcome. To limit the linear collider's length to some tens of kilometres, the beams must acquire a considerable quantity of energy per metre travelled. The collision rate (lumi...

  6. Mechanical integration studies for the CLIC vertex and inner tracking detectors

    CERN Document Server

    Villarejo Bermudez, M.A.; Gerwig, H.

    2015-01-01

    Since the publication of the CLIC Conceptual Design Report, work has proceeded in order to establish a preliminary mechanical design for the innermost CLIC detector region. This note proposes a design for the main Carbon-Fibre Reinforced Polymer (CFRP) structural elements of the inner detectors, for the beam pipe and their supports. It also describes an assembly sequence for the integration of the sensors and the mechanical components. Mechanical simulations of different structural elements and a material budget estimation are appended. Details of a proposed cabling layout for all the subdetectors are included.

  7. CLIC-ACM: Acquisition and Control System

    CERN Document Server

    Bielawski, B; Magnoni, S

    2014-01-01

    CLIC [1] (Compact Linear Collider) is a world-wide collaboration to study the next terascale lepton collider, relying upon a very innovative concept of two-beamacceleration. In this scheme, the power is transported to the main accelerating structures by a primary electron beam. The Two Beam Module (TBM) is a compact integration with a high filling factor of all components: RF, Magnets, Instrumentation, Vacuum, Alignment and Stabilization. This paper describes the very challenging aspects of designing the compact system to serve as a dedicated Acquisition & Control Module (ACM) for all signals of the TBM. Very delicate conditions must be considered, in particular radiation doses that could reach several kGy in the tunnel. In such severe conditions shielding and hardened electronics will have to be taken into consideration. In addition, with more than 300 ADC&DAC channels per ACM and about 21000 ACMs in total, it appears clearly that power consumption will be an important issue. It is also obvious that...

  8. The CLIC electron and positron polarized sources

    CERN Document Server

    Rinolfi, Louis; Bulyak, Eugene; Chehab, Robert; Dadoun, Olivier; Gai, Wei; Gladkikh, Peter; Kamitani, Takuya; Kuriki, Masao; Liu, Wanming; Maryuama, Takashi; Omori, Tsunehiko; Poelker, Matt; Sheppard, John; Urakawa, Junji; Variola, Alessandro; Vivoli, Alessandro; Yakimenko, Vitaly; Zhou, Feng; Zimmermann, Frank

    2010-01-01

    The CLIC polarized electron source is based on a DC gun where the photocathode is illuminated by a laser beam. Each micro-bunch has a charge of 6x109 e−, a width of 100 ps and a repetition rate of 2 GHz. A peak current of 10 A in the micro-bunch is a challenge for the surface charge limit of the photo-cathode. Two options are feasible to generate the 2 GHz e− bunch train: 100 ps micro-bunches can be extracted from the photo-cathode either by a 2 GHz laser system or by generating a macro-bunch using a ~200 ns laser pulse and a subsequent RF bunching system to produce the appropriate micro-bunch structure. Recent results obtained by SLAC, for the latter case, are presented. The polarized positron source is based on a positron production scheme in which polarized photons are produced by a laser Compton scattering process. The resulting circularly-polarized gamma photons are sent onto a target, producing pairs of longitudinally polarized electrons and positrons. The Compton backscattering process occurs eithe...

  9. CLIC quadrupole stabilization and nano-positioning

    CERN Document Server

    Collette, C; Artoos, K; Fernandez Carmona, P; Guinchard, M; Hauviller, C

    2010-01-01

    In the Compact LInear Collider (CLIC) currently under study, electrons and positrons will be accelerated in two linear accelerators to collide at the interaction point with an energy of 0.5- 3 TeV. This machine is constituted of a succession of accelerating structures, used to accelerate the beams of particles, and electromagnets (quadrupoles) used to focus the beams. In order to ensure good performances, the quadrupoles have to be extremely stable. Additionally, they should also have the capability to move by steps of some tens of nanometers every 20 ms with a precision of +/- 1nm. This paper proposes a holistic approach to fulfill alternatively both requirements using the same device. The concept is based on piezoelectric hard mounts to isolate the quadrupoles from the ground vibrations in the sensitive range between 1 and 20 Hz, and to provide nano-positioning capabilities. It is also shown that this strategy ensures robustness to external forces (acoustic noise, water flow for the cooling, air flow for th...

  10. X-band crab cavities for the CLIC beam delivery system

    OpenAIRE

    Burt, Graeme; Ambattu, Praveen; Dexter, Amos; Abram, Thomas; Dolgashev, V.; Tantawi, S.; Jones, R. M.

    2008-01-01

    The CLIC machine incorporates a 20 mrad crossing angle at the IP to aid the extraction of spent beams. In order to recover the luminosity lost through the crossing angle a crab cavity is proposed to rotate the bunches prior to collision. The crab cavity is chosen to have the same frequency as the main linac (11.9942 GHz) as a compromise between size, phase stability requirements and beam loading. It is proposed to use a HE11 mode travelling wave structure as the CLIC crab cavity in order to m...

  11. CLICdp Overview. Overview of physics potential at CLIC

    Directory of Open Access Journals (Sweden)

    Levy Aharon

    2015-01-01

    Full Text Available CLICdp, the CLIC detector and physics study, is an international collaboration presently composed of 23 institutions. The collaboration is addressing detector and physics issues for the future Compact Linear Collider (CLIC, a high-energy electron-positron accelerator which is one of the options for the next collider to be built at CERN. Precision physics under challenging beam and background conditions is the key theme for the CLIC detector studies. This leads to a number of cutting-edge R&D activities within CLICdp. The talk includes a brief introduction to CLIC, accelerator and detectors, hardware R&D as well as physics studies at CLIC.

  12. Tunable Achromats and CLIC Applications

    CERN Document Server

    D'Amico, T E

    2000-01-01

    It is imperative for linear colliders that the bunch length be adjustable. In most cases bunch compression is required, but recently, in the design of the Compact LInear Collider (CLIC) RF Power Source, it was shown that bunch stretching may also be necessary. In some situations, both modes may be needed, which implies the need for tunable magnetic insertions. This is even more essential in a test facility, to span a wide experimental range. In addition, flexible tuning provides a better control of the stability of an isochronous insertion. To start a numerical search for a tunable insertion from scratch is very uncertain because the related phase space is very uneven. However, a starting point obtained with an analytical approximation is often sufficient to ensure convergence. Another advantage of the analytical treatment described in this paper is that it sheds light on the shape of the entire phase space. To achieve this the isochronous achromat developed previously has been given tuning capabilities by ex...

  13. Wakefield Damping for the CLIC Crab Cavity

    Energy Technology Data Exchange (ETDEWEB)

    Ambattu, P.K.; Burt, G.; Dexter, A.C.; Carter, R.G.; /Cockcroft Inst. Accel. Sci. Tech. /Lancaster U.; Khan, V.; Jones, R.M.; /Cockcroft Inst. Accel. Sci. Tech. /Manchester U.; Dolgashev, V.; /SLAC

    2011-12-01

    A crab cavity is required in the CLIC to allow effective head-on collision of bunches at the IP. A high operating frequency is preferred as the deflection voltage required for a given rotation angle and the RF phase tolerance for a crab cavity are inversely proportional to the operating frequency. The short bunch spacing of the CLIC scheme and the high sensitivity of the crab cavity to dipole kicks demand very high damping of the inter-bunch wakes, the major contributor to the luminosity loss of colliding bunches. This paper investigates the nature of the wakefields in the CLIC crab cavity and the possibility of using various damping schemes to suppress them effectively.

  14. Wakefield damping for the CLIC crab cavity

    CERN Document Server

    Ambattu, P K; Dexter, A C; Carter, R G; Khan, V; Jones, R M; Dolgashev, V

    2009-01-01

    A crab cavity is required in the CLIC to allow effective head-on collision of bunches at the IP. A high operating frequency is preferred as the deflection voltage required for a given rotation angle and the RF phase tolerance for a crab cavity are inversely proportional to the operating frequency. The short bunch spacing of the CLIC scheme and the high sensitivity of the crab cavity to dipole kicks demand very high damping of the inter-bunch wakes, the major contributor to the luminosity loss of colliding bunches. This paper investigates the nature of the wakefields in the CLIC crab cavity and the possibility of using various damping schemes to suppress them effectively.

  15. WAKEFIELD DAMPING FOR THE CLIC CRAB CAVITY

    CERN Document Server

    Ambattu, P; Dexter, A; Carter, R; Khan, V; Jones, R; Dolgashev, V

    2009-01-01

    A crab cavity is required in the CLIC to allow effective head-on collision of bunches at the IP. A high operating frequency is preferred as the deflection voltage required for a given rotation angle and the RF phase tolerance for a crab cavity are inversely proportional to the operating frequency. The short bunch spacing of the CLIC scheme and the high sensitivity of the crab cavity to dipole kicks demand very high damping of the inter-bunch wakes, the major contributor to the luminosity loss of colliding bunches. This paper investigates the nature of the wakefields in the CLIC crab cavity and the possibility of using various damping schemes to suppress them effectively.

  16. Light-flavor squark reconstruction at CLIC

    CERN Document Server

    AUTHOR|(SzGeCERN)548062; Weuste, Lars

    2015-01-01

    We present a simulation study of the prospects for the mass measurement of TeV-scale light- flavored right-handed squark at a 3 TeV e+e collider based on CLIC technology. The analysis is based on full GEANT4 simulations of the CLIC_ILD detector concept, including Standard Model physics backgrounds and beam-induced hadronic backgrounds from two- photon processes. The analysis serves as a generic benchmark for the reconstruction of highly energetic jets in events with substantial missing energy. Several jet finding algorithms were evaluated, with the longitudinally invariant kt algorithm showing a high degree of robustness towards beam-induced background while preserving the features typically found in algorithms developed for e+e- collisions. The presented study of the reconstruction of light-flavored squarks shows that for TeV-scale squark masses, sub-percent accuracy on the mass measurement can be achieved at CLIC.

  17. Physics highlights at ILC and CLIC

    CERN Document Server

    Lukić, Strahinja

    2015-01-01

    In this lecture, the physics potential for the e+e- linear collider experiments ILC and CLIC is reviewed. The experimental conditions are compared to those at hadron colliders and their intrinsic value for precision experiments, complementary to the hadron colliders, is discussed. The detector concepts for ILC and CLIC are outlined in their most important aspects related to the precision physics. Highlights from the physics program and from the benchmark studies are given. It is shown that linear colliders are a promising tool, complementing the LHC in essential ways to test the Standard Model and to search for new physics.

  18. CLIC preparations go up a notch

    CERN Multimedia

    2007-01-01

    The Compact Linear Collider gears up for post-LHC physics with an international workshop. A schematic diagram of CLIC.In June CERN gained a new building: number 2010. And as chance would have it, this is more than just a number to its new residents. By the year 2010, teams working at the new CLIC Experimental Area, along with the already established CLIC Test Facility Three (CTF3), hope to have demonstrated the feasibility of the Compact Linear Collider and, depending on results from the LHC, embark on its final design and proposal. A workshop on 16t-18 October brought people from all around the world to CERN to exchange ideas and hear how the ambitious project is progressing. CLIC is a project that aims to extend lepton collider technology to multi-TeV energy physics, colliding leptons with a centre-of-mass-energy up to 3TeV, more than ten times the energy of the LEP. This is only possible in a linear collider, where no energy is lo...

  19. Performance of particle flow calorimetry at CLIC

    International Nuclear Information System (INIS)

    The particle flow approach to calorimetry can provide unprecedented jet energy resolution at a future high energy collider, such as the International Linear Collider (ILC). However, the use of particle flow calorimetry at the proposed multi-TeV Compact Linear Collider (CLIC) poses a number of significant new challenges. At higher jet energies, detector occupancies increase, and it becomes increasingly difficult to resolve energy deposits from individual particles. The experimental conditions at CLIC are also significantly more challenging than those at previous electron–positron colliders, with increased levels of beam-induced backgrounds combined with a bunch spacing of only 0.5 ns. This paper describes the modifications made to the PandoraPFA particle flow algorithm to improve the jet energy reconstruction for jet energies above 250 GeV. It then introduces a combination of timing and pT cuts that can be applied to reconstructed particles in order to significantly reduce the background. A systematic study is performed to understand the dependence of the jet energy resolution on the jet energy and angle, and the physics performance is assessed via a study of the energy and mass resolution of W and Z particles in the presence of background at CLIC. Finally, the missing transverse momentum resolution is presented, and the fake missing momentum is quantified. The results presented in this paper demonstrate that high granularity particle flow calorimetry leads to a robust and high resolution reconstruction of jet energies and di-jet masses at CLIC.

  20. The chloride intracellular channel protein CLIC5 is expressed at high levels in hair cell stereocilia and is essential for normal inner ear function.

    Science.gov (United States)

    Gagnon, Leona H; Longo-Guess, Chantal M; Berryman, Mark; Shin, Jung-Bum; Saylor, Katherine W; Yu, Heping; Gillespie, Peter G; Johnson, Kenneth R

    2006-10-01

    Although CLIC5 is a member of the chloride intracellular channel protein family, its association with actin-based cytoskeletal structures suggests that it may play an important role in their assembly or maintenance. Mice homozygous for a new spontaneous recessive mutation of the Clic5 gene, named jitterbug (jbg), exhibit impaired hearing and vestibular dysfunction. The jbg mutation is a 97 bp intragenic deletion that causes skipping of exon 5, which creates a translational frame shift and premature stop codon. Western blot and immunohistochemistry results confirmed the predicted absence of CLIC5 protein in tissues of jbg/jbg mutant mice. Histological analysis of mutant inner ears revealed dysmorphic stereocilia and progressive hair cell degeneration. In wild-type mice, CLIC5-specific immunofluorescence was detected in stereocilia of both cochlear and vestibular hair cells and also along the apical surface of Kolliker's organ during cochlear development. Refined immunolocalization in rat and chicken vestibular hair cells showed that CLIC5 is limited to the basal region of the hair bundle, similar to the known location of radixin. Radixin immunostaining appeared reduced in hair bundles of jbg mutant mice. By mass spectrometry and immunoblotting, CLIC5 was shown to be expressed at high levels in stereocilia of the chicken utricle, in an approximate 1:1 molar ratio with radixin. These results suggest that CLIC5 associates with radixin in hair cell stereocilia and may help form or stabilize connections between the plasma membrane and the filamentous actin core. PMID:17021174

  1. Achievements and Future Plans of CLIC Test Facilities

    CERN Document Server

    Braun, Hans Heinrich

    2001-01-01

    CTF2 was originally designed to demonstrate the feasibility of two-beam acceleration with high current drive beams and a string of 30 GHz CLIC accelerating structure prototypes (CAS). This goal was achieved in 1999 and the facility has since been modified to focus on high gradient testing of CAS's and 30 GHz single cell cavities (SCC). With these modifications, it is now possible to provide 30 GHz RF pulses of more than 150 MW and an adjustable pulselength from 3 to 15 ns. While the SCC results are promising, the testing of CAS's revealed problems of RF breakdown and related surface damage. As a consequence, a new R&D program has been launched to advance the understanding of RF breakdown processes, to improve surface properties, investigate new materials and to optimise the structure geometries of the CAS's. In parallel the construction of a new facility named CTF3 has started. CTF3 will mainly serve two purposes. The first is the demonstration of the CLIC drive beam generation scheme. CTF3 will acceler-a...

  2. Structures and magnetism of mono-palladium and mono-platinum doped Au25(PET)18 nanoclusters.

    Science.gov (United States)

    Tian, Shubo; Liao, Lingwen; Yuan, Jinyun; Yao, Chuanhao; Chen, Jishi; Yang, Jinlong; Wu, Zhikun

    2016-08-01

    Herein we report three important results of widespread interest, which are (1) the crystal structure of [Au24Pt(PET)18](0), (2) the crystal structure of [Au24Pd(PET)18](0) and (3) the main source of magnetism in [Au25(PET)18](0). PMID:27379360

  3. Cherenkov Fibers for Beam Loss Monitoring at the CLIC Two Beam Module

    CERN Document Server

    van Hoorne, Jacobus Willem; Holzer, E B

    The Compact Linear Collider (CLIC) study is a feasibility study aiming at a nominal center of mass energy of 3TeV and is based on normal conducting travelling-wave accelerating structures, operating at very high field gradients of 100 MV/m. Such high fields require high peak power and hence a novel power source, the CLIC two beam system, has been developed, in which a high intensity, low energy drive beam (DB) supplies energy to a high energy, low intensity main beam (MB). At the Two Beam Modules (TBM), which compose the 2x21km long CLIC main linac, a protection against beam losses resulting from badly controlled beams is necessary and particularly challenging, since the beam power of both main beam (14 MW) and drive beam (70 MW) is impressive. To avoid operational downtimes and severe damages to machine components, a general Machine Protection System (MPS) scheme has been developed. The Beam Loss Monitoring (BLM) system is a key element of the CLIC machine protection system. Its main role will be to detect p...

  4. Expression, purification, crystallization and preliminary X-ray diffraction analysis of chloride intracellular channel 2 (CLIC2)

    International Nuclear Information System (INIS)

    Chloride intracellular channel 2 (CLIC2) belongs to a family of intracellular chloride-channel proteins that can exist in a soluble form. The expression, purification and crystallization in two different crystal forms of human CLIC2 is reported. The chloride intracellular channel (CLIC) family of proteins are unusual in that they can exist in either an integral membrane-channel form or a soluble form. Here, the expression, purification, crystallization and preliminary diffraction analysis of CLIC2, one of the least-studied members of this family, are reported. Human CLIC2 was crystallized in two different forms, both in the presence of reduced glutathione and both of which diffracted to better than 1.9 Å resolution. Crystal form A displayed P212121 symmetry, with unit-cell parameters a = 44.0, b = 74.7, c = 79.8 Å. Crystal form B displayed P21 symmetry, with unit-cell parameters a = 36.0, b = 66.9, c = 44.1 Å. Structure determination will shed more light on the structure and function of this enigmatic family of proteins

  5. CLIC Post-Collision Line Luminosity Monitoring

    CERN Document Server

    Appleby, R B; Deacon, L; Geschwendtner, E

    2011-01-01

    The CLIC post collision line is designed to transport the un-collided beams and the products of the collided beams with a total power of 14MW to the main beam dump. Full Monte Carlo simulation has been done for the description of the CLIC luminosity monitoring in the post collision line. One method of the luminosity diagnostic is based on the detection of high energy muons produced by beamstrahlung photons in the main beam dump. The disrupted beam and the beamstrahlung photons produce at the order of 106 muons per bunch crossing per cm2, with energies higher than 10 GeV. Threshold Cherenkov counters are considered after the beam dump for the detection of these high energy muons. Another method for luminosity monitoring is presented using the direct detection of the beamstrahlung photons.

  6. Light-flavor squark reconstruction at CLIC

    Science.gov (United States)

    Simon, Frank; Weuste, Lars

    2015-08-01

    We present a simulation study of the prospects for the mass measurement of TeV-scale light-flavored right-handed squarks at a 3 TeV collider based on CLIC technology. In the considered model, these particles decay into their standard-model counterparts and the lightest neutralino, resulting in a signature of two jets plus missing energy. The analysis is based on full GEANT4 simulations of the CLIC_ILD detector concept, including Standard Model physics backgrounds and beam-induced hadronic backgrounds from two-photon processes. The analysis serves as a generic benchmark for the reconstruction of highly energetic jets in events with substantial missing energy. Several jet finding algorithms were evaluated, with the longitudinally invariant algorithm showing a high degree of robustness towards beam-induced background while preserving the features typically found in algorithms developed for collisions. The presented study of the reconstruction of light-flavored squarks shows that for TeV-scale squark masses, sub-percent accuracy on the mass measurement can be achieved at CLIC.

  7. Submicron multi-bunch BPM for CLIC

    Energy Technology Data Exchange (ETDEWEB)

    Schmickler, H.; Soby, L.; /CERN; Lunin, A.; Solyak, N.; Wendt, M.; /Fermilab

    2010-08-01

    A common-mode free cavity BPM is currently under development at Fermilab within the ILC-CLIC collaboration. This monitor will be operated in a CLIC Main Linac multi-bunch regime, and needs to provide both, high spatial and time resolution. We present the design concept, numerical analysis, investigation on tolerances and error effects, as well as simulations on the signal response applying a multi-bunch stimulus. The proposed CERN linear collider (CLIC) requires a very precise measurement of beam trajectory to preserve the low emittance when transporting the beam through the Main Linac. An energy chirp within the bunch train will be applied to measure and minimize the dispersion effects, which require high resolution (in both, time and space) beam position monitors (BPM) along the beam-line. We propose a low-Q waveguide loaded TM{sub 110} dipole mode cavity as BPM, which is complemented by a TM{sub 010} monopole mode resonator of same resonant frequency for reference signal purposes. The design is based on a well known TM{sub 110} selective mode coupling idea.

  8. CLIC crab cavity design optimisation for maximum luminosity

    International Nuclear Information System (INIS)

    The bunch size and crossing angle planned for CERN's compact linear collider CLIC dictate that crab cavities on opposing linacs will be needed to rotate bunches of particles into alignment at the interaction point if the desired luminosity is to be achieved. Wakefield effects, RF phase errors between crab cavities on opposing linacs and unpredictable beam loading can each act to reduce luminosity below that anticipated for bunches colliding in perfect alignment. Unlike acceleration cavities, which are normally optimised for gradient, crab cavities must be optimised primarily for luminosity. Accepting the crab cavity technology choice of a 12 GHz, normal conducting, travelling wave structure as explained in the text, this paper develops an analytical approach to optimise cell number and iris diameter.

  9. CLIC Crab Cavity Design Optimisation for Maximum Luminosity

    Energy Technology Data Exchange (ETDEWEB)

    Dexter, A.C.; /Lancaster U. /Cockcroft Inst. Accel. Sci. Tech.; Burt, G.; /Lancaster U. /Cockcroft Inst. Accel. Sci. Tech.; Ambattu, P.K.; /Lancaster U. /Cockcroft Inst. Accel. Sci. Tech.; Dolgashev, V.; /SLAC; Jones, R.; /Manchester U.

    2012-04-25

    The bunch size and crossing angle planned for CERN's compact linear collider CLIC dictate that crab cavities on opposing linacs will be needed to rotate bunches of particles into alignment at the interaction point if the desired luminosity is to be achieved. Wakefield effects, RF phase errors between crab cavities on opposing linacs and unpredictable beam loading can each act to reduce luminosity below that anticipated for bunches colliding in perfect alignment. Unlike acceleration cavities, which are normally optimised for gradient, crab cavities must be optimised primarily for luminosity. Accepting the crab cavity technology choice of a 12 GHz, normal conducting, travelling wave structure as explained in the text, this paper develops an analytical approach to optimise cell number and iris diameter.

  10. CLIC crab cavity design optimisation for maximum luminosity

    Energy Technology Data Exchange (ETDEWEB)

    Dexter, A.C., E-mail: a.dexter@lancaster.ac.uk [Lancaster University, Lancaster, LA1 4YR (United Kingdom); Cockcroft Institute, Daresbury, Warrington, WA4 4AD (United Kingdom); Burt, G.; Ambattu, P.K. [Lancaster University, Lancaster, LA1 4YR (United Kingdom); Cockcroft Institute, Daresbury, Warrington, WA4 4AD (United Kingdom); Dolgashev, V. [SLAC, Menlo Park, CA 94025 (United States); Jones, R. [University of Manchester, Manchester, M13 9PL (United Kingdom)

    2011-11-21

    The bunch size and crossing angle planned for CERN's compact linear collider CLIC dictate that crab cavities on opposing linacs will be needed to rotate bunches of particles into alignment at the interaction point if the desired luminosity is to be achieved. Wakefield effects, RF phase errors between crab cavities on opposing linacs and unpredictable beam loading can each act to reduce luminosity below that anticipated for bunches colliding in perfect alignment. Unlike acceleration cavities, which are normally optimised for gradient, crab cavities must be optimised primarily for luminosity. Accepting the crab cavity technology choice of a 12 GHz, normal conducting, travelling wave structure as explained in the text, this paper develops an analytical approach to optimise cell number and iris diameter.

  11. The physics benchmark processes for the detector performance studies used in CLIC CDR Volume 3

    CERN Document Server

    Allanach, B.J.; Desch, K.; Ellis, J.; Giudice, G.; Grefe, C.; Kraml, S.; Lastovicka, T.; Linssen, L.; Marschall, J.; Martin, S.P.; Muennich, A.; Poss, S.; Roloff, P.; Simon, F.; Strube, J.; Thomson, M.; Wells, J.D.

    2012-01-01

    This note describes the detector benchmark processes used in volume 3 of the CLIC conceptual design report (CDR), which explores a staged construction and operation of the CLIC accelerator. The goal of the detector benchmark studies is to assess the performance of the CLIC ILD and CLIC SiD detector concepts for different physics processes and at a few CLIC centre-of-mass energies.

  12. A CLIC-Prototype Higgs Factory

    OpenAIRE

    Belusevic, Radoje; Higo, Toshiyasu

    2012-01-01

    We propose that a pair of electron linacs with high accelerating gradients and an optical FEL be built at an existing laboratory. The linacs would employ CLIC-type rf cavities and a klystron-based power source; a two-beam scheme could be implemented at a later stage. The proposed facility would serve primarily as an e+e-/gamma-gamma Higgs-boson factory. The rich set of final states in e+e- and gamma-gamma collisions would play an essential role in measuring the mass, spin, parity, two-photon ...

  13. Conceptual Design for CLIC Gun Pulser

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Tao [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2016-01-08

    The Compact Linear Collider (CLIC) is a proposed future electron-positron collider, designed to perform collisions at energies from 0.5 to 5 TeV, with a nominal design optimized for 3 TeV (Dannheim, 2012). The Drive Beam Accelerator consists of a thermionic DC gun, bunching section and an accelerating section. The thermionic gun needs deliver a long (~143us) pulse of current into the buncher. A pulser is needed to drive grid of the gun to generate a stable current output. This report explores the requirements of the gun pulser and potential solutions to regulate grid current.

  14. Electro-Weak Fits at CLIC

    CERN Document Server

    De Curtis, S

    2002-01-01

    The aim of the future linear colliders is to extend the sensitivity to new physics beyond the reach of the LHC. Several models predict the existence of new vector resonances in the multi-TeV region. We review the existing limits on the masses of these new resonances from LEP/SLC and TEVATRON data and from the atomic parity violation measurements, in some specific models. We study the potential of a multi-TeV e+e- collider, such as CLIC, for the determination of their properties and nature.

  15. Performance of Particle Flow Calorimetry at CLIC

    CERN Document Server

    Marshall, J.S.; Thomson, M.A.

    2013-01-01

    The experimental conditions at CLIC are also significantly more challenging than those at previous electron-positron colliders, with increased levels of beam-induced backgrounds combined with a bunch spacing of only 0.5 ns. This paper describes the modifications made to the PandoraPFA particle flow algorithm to improve the jet energy reconstruction for jet energies above 250 GeV. It then introduces a combination of timing and pT cuts that can be applied to reconstructed particles in order to significantly reduce the background. A systematic study is...

  16. X-band crab cavities for the CLIC beam delivery system

    CERN Document Server

    Burt, G; Dexter, A C; Abram, T; Dolgashev, V; Tantawi, S; Jones, R M

    2009-01-01

    The CLIC machine incorporates a 20 mrad crossing angle at the IP to aid the extraction of spent beams. In order to recover the luminosity lost through the crossing angle a crab cavity is proposed to rotate the bunches prior to collision. The crab cavity is chosen to have the same frequency as the main linac (11.9942 GHz) as a compromise between size, phase stability requirements and beam loading. It is proposed to use a HE11 mode travelling wave structure as the CLIC crab cavity in order to minimise beam loading and mode separation. The position of the crab cavity close to the final focus enhances the effect of transverse wake-fields so effective wake-field damping is required. A damped detuned structure is proposed to suppress and de-cohere the wake-field hence reducing their effect. Design considerations for the CLIC crab cavity will be discussed as well as the proposed high power testing of these structures at SLAC.

  17. Status of vertex and tracking detector R&D at CLIC

    CERN Document Server

    Firu, Elena

    2015-01-01

    The physics aims at the future CLIC high-energy linear e+e- collider set very high precision requirements on the performance of the vertex and tracking detectors. Moreover, these detectors have to be well adapted to the experimental conditions, such as the bunch train structure of the beam and the presence of beam-induced backgrounds. The principal challenges are: a point resolution of a few micron, ultra-low mass (~0.2% X0 per layer for the inner vertex region), very low power dissipation (compatible with air-flow cooling in the inner vertex region) and pulsed power operation, complemented with ~10 ns time stamping capabilities. An overview of the R&D program for pixel and tracking detectors at CLIC will be presented, including recent results on an innovative hybridisation concept based on capacitive coupling between active sensors (HV-CMOS) and readout ASICs (CLICpix).

  18. Study of the Thermo-Mechanical Behavior of the CLIC Two-Beam Modules

    CERN Document Server

    Rossi, F; Riddone, G; Österberg, K; Kossyvakis, I; Gudkov, D; Samochkine, A

    2013-01-01

    The final luminosity target of the Compact LInear Collider (CLIC) imposes a micron-level stability requirement on the two-meter repetitive two-beam modules constituting the main linacs. Two-beam prototype modules are being assembled to extensively study their thermo-mechanical behaviour under different operation modes. The power dissipation occurring in the modules will be reproduced and the efficiency of the corresponding cooling systems validated. At the same time, the real environmental conditions present in the CLIC tunnel will be studied. Air conditioning and ventilation systems have been installed in the dedicated laboratory. The air temperature will be changed from 20 to 40°C, while the air flow rate will be varied up to 0.8 m/s. During all experimental tests, the alignment of the RF structures will be monitored to investigate the influence of power dissipation and air temperature on the overall thermo-mechanical behaviour. \

  19. Thermo-Mechanical tests for the CLIC two-beam module study

    CERN Document Server

    Xydou, A; Riddone, G; Daskalaki, E

    2014-01-01

    The luminosity goal of CLIC requires micron level precision with respect to the alignment of the components on its two-meter long modules, composing the two main linacs. The power dissipated inside the module components introduces mechanical deformations affecting their alignment and therefore the resulting machine performance. Several two-beam prototype modules must be assembled to extensively measure their thermo-mechanical behavior under different operation modes. In parallel, the real environmental conditions present in the CLIC tunnel should be studied. The air conditioning and ventilation system providing specified air temperature and flow has been installed in the dedicated laboratory. The power dissipation occurring in the modules is being reproduced by the electrical heaters inserted inside the RF structure mock-ups and the quadrupoles. The efficiency of the cooling systems is being verified and the alignment of module components is monitored. The measurement results will be compared to finite elemen...

  20. M10.3.4: CLIC crab cavity specifications completed

    CERN Document Server

    Dexter, A; Ambattu, P; Shinton, I; Jones, R

    2010-01-01

    The starting point of Sub-task 2 is to document the currently anticipated requirements for the CLIC crab cavity system. This milestone concerns completion of the basic specifications for the CLIC crab cavity system. This comprises kick, power requirement, phase and amplitude stability, technology choice, and RF layout. The wakefield calculations of a baseline CLIC cavity will be used to estimate the required damping of the higher order modes as well as other special modes in crab cavities (the lower and same order modes).

  1. CLIC CRAB CAVITY SPECIFICATIONS MILESTONE: M10.3.4

    CERN Document Server

    Ambattu, P; Dexter, A; Jones, R; McIntosh, P; Shinton, I

    2010-01-01

    The starting point of Sub-task 2 is to document the currently anticipated requirements for the CLIC crab cavity system. This milestone concerns completion of the basic specifications for the CLIC crab cavity system. This comprises kick, power requirement, phase and amplitude stability, technology choice, and RF layout. The wakefield calculations of a baseline CLIC cavity will be used to estimate the required damping of the higher order modes as well as other special modes in crab cavities (the lower and same order modes).

  2. Structural features and relaxation properties of PET/PC blends containing impact strength modifier and chain extender

    Directory of Open Access Journals (Sweden)

    2009-10-01

    Full Text Available It has been investigated how methylene diphenyl diisocyanate (MDI influences the morphology, rheological, mechanical and relaxation properties, as well as PET crystallizability, of PET/PC/(PP/EPDM ternary blends produced by the reactive extrusion process. It appears that irrespective of phase structure of the blends, MDI causes a rise in melt viscosity (decreased MFI-values of the material which is the result of an increased molecular weight of the macromolecules; PET crystallization becomes retarded. MDI improves compatibility between PET and PC in PET/PC/(PP/EPDM ternary blends. Addition of MDI leads to higher values of the dynamic shear modulus for PET high elastic state (in the temperature range between Tg PET and cool crystallization temperature of PET; the PET cool crystallization and melt crystallization processes become retarded; the PET and PC glass transition temperatures approach one another. MDI has been shown not to influence significantly the blend morphology or the character of interaction between the PP/EPDM disperse phase and PET/PC blend matrix.

  3. Estrutura da cadeia reversa: "caminhos" e "descaminhos" da embalagem PET Structure of the reverse chain: "ways" of PET packing

    Directory of Open Access Journals (Sweden)

    Sylmara Lopes Francelino Gonçalves-Dias

    2006-12-01

    Full Text Available O trabalho propõe-se a discutir as possibilidades, limites e desafios da reciclagem de PET - Politereftalato de Etileno. Como fundamentação teórico-conceitual, recorre à discussão sobre a natureza e o alcance da logística reversa, analisando as estratégias para estruturação da cadeia de reciclagem. A pesquisa é de caráter exploratório, com adoção de diferentes estratégias para a coleta de dados, envolvendo fontes secundárias produzidas por órgãos públicos, instituições especializadas e mídia, e ainda entrevistas semi-estruturadas com especialistas na área. Os resultados apontam que múltiplos atores estão envolvidos na estrutura da cadeia reversa do PET e que, apesar do avanço no volume de reciclagem, nenhum dos setores, seja público ou privado, consegue individualmente organizar-se para o alcance da efetividade operacional e ambiental desejável no cenário brasileiro. O alcance de bons resultados depende, sobretudo, do investimento nos dois extremos da cadeia reversa: na coleta seletiva e no mercado para o produto reciclado.The work discuss the possibilities, limits and challenges of the recycling of PET packing in the Brazilian case. The authors analyze the nature and the function of the reverse logistics and its strategies for articulation of the recycling chain. The research is based in the exploratory methodological approach, with adoption of different strategies for the collection of data, involving secondary sources produced by public institutions, specialized organizations and media, and still, interviews semi-structured with specialists in the area. The results point that the Brazilian public and private sectors doesn’t get to organize this activity in the desirable environmental scale. Good performances in the PET packing reverse chain depends on investing in the selective collection and in the market for the recycled products.

  4. 3D quantification of soil structure and functioning based on PET and CT scanning techniques

    DEFF Research Database (Denmark)

    Garbout, Amin

    This thesis explores the potential of PET and CT scanning techniques to quantify and visualize soil structure, root development, and soil/plant interactions. At the investigated scale, these non-invasive and nondestructive techniques have some obvious advantages compared with most other techniques....... The processed measurements show some expected and a few unexpected effects (or lack of effects) on different characteristics of soil structure. The combination of CT and PET scanning in an air plant soil controller system revealed some very interesting research possibilities. Interactions between soil...

  5. Summary of the BDS and MDI CLIC08 Working Group

    CERN Document Server

    Tomás, R; Ahmed, I; Ambatu, PK; Angal-Kalinin, D; Barlow, R; Baud, J P; Bolzon, B; Braun, H; Burkhardt, H; Burt, GC; Corsini, R; Dalena, B; Dexter, AC; Dolgashev, V; Elsener, K; Fernandez Hernando, JL; Gaillard, G; Geffroy, N; Jackson, F; Jeremie, A; Jones, RM; McIntosh, P; Moffeit, K; Peltier, F; Resta-López, J; Rumolo, G; Schulte, D; Seryi, A; Toader, A; Zimmermann, F

    2008-01-01

    This note summarizes the presentations held within the Beam Delivery System and Machine Detector Interface working group of the CLIC08 workshop. The written contributions have been provided by the presenters on a voluntary basis.

  6. Luminosity Upgrade of CLIC LHC ep/gp Collider

    CERN Document Server

    Aksakal, H; Nergiz, Z; Schulte, D; Zimmermann, F

    2007-01-01

    An energy frontier or QCD Explorer ep and collider can be realized by colliding high-energy photons generated by Compton backscattered off a CLIC electron beam, at either 75 GeV or 1.5 TeV, with protons or ions stored in the LHC. In this study we discuss a performance optimization of this type of collider by tailoring the parameters of both CLIC and LHC. An estimate of the ultimately achievable luminosity is given.

  7. A high resolution cavity BPM for the CLIC Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Chritin, N.; Schmickler, H.; Soby, L.; /CERN; Lunin, A.; Solyak, N.; Wendt, M.; Yakovlev, V.; /Fermilab

    2010-08-01

    In frame of the development of a high resolution BPM system for the CLIC Main Linac we present the design of a cavity BPM prototype. It consists of a waveguide loaded dipole mode resonator and a monopole mode reference cavity, both operating at 15 GHz, to be compatible with the bunch frequencies at the CLIC Test Facility. Requirements, design concept, numerical analysis, and practical considerations are discussed.

  8. $2\\times250$ GeV CLIC $\\gamma\\gamma$ Collider Based on its Drive Beam FEL

    CERN Document Server

    Aksakal, Husnu

    2007-01-01

    CLIC is a linear $e^+e^-$ ($\\gamma\\gamma$) collider project which uses a drive beam to accelerate the main beam. The drive beam provides RF power for each corresponding unit of the main linac through energy extracting RF structures. CLIC has a wide range of center-of-mass energy options from 150 GeV to 3 TeV. The present paper contains optimization of Free Electron Laser (FEL) using one bunch of CLIC drive beam in order to provide polarized light amplification using appropriate wiggler and luminosity spectrum of $\\gamma\\gamma$ collider for $E_{cm}$=0.5 TeV. Then amplified laser can be converted to a polarized high-energy $\\gamma$ beam at the Conversion point (CP-prior to electron positron interaction point) in the process of Compton backscattering. At the CP a powerful laser pulse (FEL) focused to main linac electrons (positrons). Here this scheme described and it is show that CLIC drive beam parameters satisfy the requirement of FEL additionally essential undulator parameters has been defined. Achievable $\\g...

  9. CLIC1 regulates dendritic cell antigen processing and presentation by modulating phagosome acidification and proteolysis

    Science.gov (United States)

    Salao, Kanin; Jiang, Lele; Li, Hui; Tsai, Vicky W.-W.; Husaini, Yasmin; Curmi, Paul M. G.; Brown, Louise J.; Brown, David A.

    2016-01-01

    ABSTRACT Intracellular chloride channel protein 1 (CLIC1) participates in inflammatory processes by regulating macrophage phagosomal functions such as pH and proteolysis. Here, we sought to determine if CLIC1 can regulate adaptive immunity by actions on dendritic cells (DCs), the key professional antigen presenting cells. To do this, we first generated bone marrow-derived DCs (BMDCs) from germline CLIC1 gene-deleted (CLIC1−/−) and wild-type (CLIC1+/+) mice, then studied them in vitro and in vivo. We found phagocytosis triggered cytoplasmic CLIC1 translocation to the phagosomal membrane where it regulated phagosomal pH and proteolysis. Phagosomes from CLIC1−/− BMDCs displayed impaired acidification and proteolysis, which could be reproduced if CLIC1+/+, but not CLIC1−/− cells, were treated with IAA94, a CLIC family ion channel blocker. CLIC1−/− BMDC displayed reduced in vitro antigen processing and presentation of full-length myelin oligodendrocyte glycoprotein (MOG) and reduced MOG-induced experimental autoimmune encephalomyelitis. These data suggest that CLIC1 regulates DC phagosomal pH to ensure optimal processing of antigen for presentation to antigen-specific T-cells. Further, they indicate that CLIC1 is a novel therapeutic target to help reduce the adaptive immune response in autoimmune diseases. PMID:27113959

  10. A CLIC-Prototype Higgs Factory

    CERN Document Server

    Belusevic, Radoje

    2012-01-01

    We propose that a pair of electron linacs with high accelerating gradients and an optical FEL be built at an existing laboratory. The linacs would employ CLIC-type rf cavities and a klystron-based power source; a two-beam scheme could be implemented at a later stage. The proposed facility would serve primarily as an e+e-/gamma-gamma Higgs-boson factory. The rich set of final states in e+e- and gamma-gamma collisions would play an essential role in measuring the mass, spin, parity, two-photon width and trilinear self-coupling of the Higgs-boson, as well as its couplings to fermions and gauge bosons. These quantities are difficult to determine with only one initial state. For some processes within and beyond the Standard Model, the required CM energy is considerably lower at the proposed facility than at an e+e- or proton collider.

  11. Conceptual Design of the CLIC Damping Rings

    CERN Document Server

    Papaphilippou, Y; Barnes, M; Calatroni, S; Chiggiato, P; Corsini, R; Grudiev, A; Koukovini, E; Lefevre, T; Martini, M; Modena, M; Mounet, N; Perin, A; Renier, Y; Russenschuck, S; Rumolo, G; Schoerling, D; Schulte, D; Schmickler, H; Taborelli, M; Vandoni, G; Zimmermann, F; Zisopoulos, P; Boland, M; Palmer, M; Bragin, A; Levichev, E; Syniatkin, S; Zolotarev, K; Vobly, P; Korostelev, M; Vivoli, A; Belver-Aguilar, C; Faus-Golfe, A; Rinolfi, L; Bernhard, A; Pivi, M; Smith, S; Rassool, R; Wootton, K

    2012-01-01

    The CLIC Damping rings are designed to produce unprecedentedly low-emittances of 500 nm and 5 nm normalized at 2.86 GeV, with high bunch charge, necessary for the performance of the collider. The large beam brightness triggers a number of beam dynamics and technical challenges. Ring parameters such as energy, circumference, lattice, momentum compaction, bending and superconducting wiggler fields are carefully chosen in order to provide the target emittances under the influence of intrabeam scattering but also reduce the impact of collective effects such as space-charge and coherent synchrotron radiation. Mitigation techniques for two stream instabilities have been identified and tested. The low vertical emittance is achieved by modern orbit and coupling correction techniques. Design considerations and plans for technical systems, such as wigglers, transfer systems, vacuum, RF cavities, instrumentation and feedback are finally reviewed.

  12. Impedance effects in the CLIC damping rings

    CERN Document Server

    Koukovini-Platia, E; Mounet, N; Rumolo, G; Salvant, B

    2011-01-01

    Due to the unprecedented brilliance of the beams, the performance of the Compact Linear Collider (CLIC) damping rings (DR) is affected by collective effects. Single bunch instability thresholds based on a broad-band resonator model and the associated coherent tune shifts have been evaluated with the HEADTAIL code. Simulations performed for positive and negative values of chromaticity showed that higher order bunch modes can be potentially dangerous for the beam stability. This study also includes the effects of high frequency resistive wall impedance due to different coatings applied on the chambers of the wigglers for e-cloud mitigation and/or ultra-low vacuum pressure. The impact of the resistive wall wake fields on the transverse impedance budget is finally discussed.

  13. Requirements of CLIC Beam Loss Monitoring System

    CERN Document Server

    Sapinski, M; Holzer, EB; Jonker, M; Mallows, S; Otto, T; Welsch, C

    2010-01-01

    The Compact Linear Collider (CLIC) [1] is a proposed multi-TeV linear electron-positron collider being designed by a world-wide collaboration. It is based on a novel twobeam acceleration scheme in which two beams (drive and main beam) are placed in parallel to each other and energy is transferred from the drive beam to the main one. Beam losses on either of them can have catastrophic consequences for the machine, because of high intensity (drive beam) or high energy and small emittance (main beam). In the framework of machine protection, a Beam Loss Monitoring (BLM) system has to be put in place. This paper discusses the requirements for the beam loss system in terms of detector sensitivity, resolution, dynamic range and ability to distinguish losses originating from various sources. The two-beam module where the protection from beam losses is particularly challenging and important, is studied.

  14. Structured light 3D tracking system for measuring motions in PET brain imaging

    DEFF Research Database (Denmark)

    Olesen, Oline Vinter; Jørgensen, Morten Rudkjær; Paulsen, Rasmus Reinhold;

    2010-01-01

    Patient motion during scanning deteriorates image quality, especially for high resolution PET scanners. A new proposal for a 3D head tracking system for motion correction in high resolution PET brain imaging is set up and demonstrated. A prototype tracking system based on structured light with a...... DLP projector and a CCD camera is set up on a model of the High Resolution Research Tomograph (HRRT). Methods to reconstruct 3D point clouds of simple surfaces based on phase-shifting interferometry (PSI) are demonstrated. The projector and camera are calibrated using a simple stereo vision procedure...... where the projector is treated as a camera. Additionally, the surface reconstructions are corrected for the non-linear projector output prior to image capture. The results are convincing and a first step toward a fully automated tracking system for measuring head motions in PET imaging...

  15. Simultaneous evaluation of brain tumour metabolism, structure and blood volume using [(18)F]-fluoroethyltyrosine (FET) PET/MRI

    DEFF Research Database (Denmark)

    Henriksen, Otto M; Larsen, Vibeke A; Muhic, Aida; Hansen, Adam E; Larsson, Henrik B W; Poulsen, Hans S; Law, Ian

    2016-01-01

    at least one modality for any pair of modalities. In 56 % of the patients susceptibility artefacts in DSC BV maps overlapped the tumour on MRI. CONCLUSION: The study demonstrated that although tumour volumes determined by BV MRI and FET PET were quantitatively correlated, their spatial congruence in......PURPOSE: Both [(18)F]-fluoroethyltyrosine (FET) PET and blood volume (BV) MRI supplement routine T1-weighted contrast-enhanced MRI in gliomas, but whether the two modalities provide identical or complementary information is unresolved. The aims of the study were to investigate the feasibility of...... simultaneous structural MRI, BV MRI and FET PET of gliomas using an integrated PET/MRI scanner and to assess the spatial and quantitative agreement in tumour imaging between BV MRI and FET PET. METHODS: A total of 32 glioma patients underwent a 20-min static simultaneous PET/MRI acquisition on a Siemens m...

  16. PET in Lung Cancer

    OpenAIRE

    Hans C. Steinert,

    2005-01-01

    Accurate tumor staging is essential for choosing the appropriate treatment strategy inpatients with lung cancer. It has already been shown that FDG-PET is highly accurate inclassifying lung nodules as benign or malignant. Integrated PET-CT enables the exactmatching of focal abnormalities on PET to anatomic structures on CT. PET-CT is superior indiagnostic accuracy for T staging and differentiation between tumor and peritumoral atelectasis.PET has also proved to be a very effective staging mod...

  17. Effect of gamma radiation on the structural and optical properties of Polyethyleneterephthalate (PET) polymer

    International Nuclear Information System (INIS)

    Effect of 1.25 MeV gamma radiation on the structural and optical properties of virgin and gamma irradiated (0–2000 kGy) Polyethyleneterephthalate (PET) polymer samples are analyzed using powder X-ray diffractometer and UV–vis spectrophotometer. Diffraction pattern of PET polymer indicates the semi-crystalline in nature whereas the crystallinity increases with increasing dose of irradiation. The remarkable variation in crystallite size is also observed. The absorption and activation energy increase and the optical band gap (Eg) decreases with increasing dose in UV–vis studies. The existence of the maximum absorption, their shifting and broadening due to gamma irradiation in PET polymer are also discussed. - Highlights: ► PET is the transparent polymer and semi- crystalline. ► Crystallinity increases with increasing dose of irradiation of polymer. ► The remarkable variation in crystallite sizes was also observed in polymer. ► The absorption and activation energy increase and where as the optical band gap (Eg) decrease with increasing dose.

  18. Minimizing Emittance for the CLIC Damping Ring

    CERN Document Server

    Braun, H; Levitchev, E; Piminov, P; Schulte, Daniel; Siniatkin, S; Vobly, P P; Zimmermann, Frank; Zolotarev, Konstantin V; CERN. Geneva

    2006-01-01

    The CLIC damping rings aim at unprecedented small normalized equilibrium emittances of 3.3 nm vertical and 550 nm horizontal, for a bunch charge of 2.6·109 particles and an energy of 2.4 GeV. In this parameter regime the dominant emittance growth mechanism is intra-beam scattering. Intense synchrotron radiation damping from wigglers is required to counteract its effect. Here the overall optimization of the wiggler parameters is described, taking into account state-of-the-art wiggler technologies, wiggler effects on dynamic aperture, and problems of wiggler radiation absorption. Two technical solutions, one based on superconducting magnet technology the other on permanent magnets are presented. Although dynamic aperture and tolerances of this ring design remain challenging, benefits are obtained from the strong damping. For optimized wigglers, only bunches for a single machine pulse may need to be stored, making injection/extraction particularly simple and limiting the synchrotron-radiation power. With a 36...

  19. CLIC/ILC Researchers Explore New Avenues for Collaboration

    CERN Multimedia

    Katarina Anthony

    2010-01-01

    Researchers from CLIC and ILC met for their first common International Workshop on Linear Colliders, which was held in Geneva from 18 to 22 October. Although the talks were mostly scientific and technical, the political message behind them was a breakthrough, as the workshop showed the progress made in unifying the two communities.   The International Workshop on Linear Colliders (IWLC), which was organised by the European Committee for Future Accelerators, hosted by CERN, and held at CERN and the International Conference Centre in Geneva, attracted a large audience of about 500 experts. Although there have been other joint conferences between the CLIC and ILC communities before, they have all been focused on specific technical and/or managerial issues. The IWLC was part of an ongoing effort by CLIC and ILC to provide an environment in which researchers can exchange ideas, inform their peers about their most recent achievements and work together on common issues. Given the possible technical ov...

  20. X-Band Crab Cavities for the CLIC Beam Delivery System

    International Nuclear Information System (INIS)

    The CLIC machine incorporates a 20 mrad crossing angle at the IP to aid the extraction of spent beams. In order to recover the luminosity lost through the crossing angle a crab cavity is proposed to rotate the bunches prior to collision. The crab cavity is chosen to have the same frequency as the main linac (11.9942 GHz) as a compromise between size, phase stability requirements and beam loading. It is proposed to use a HE11 mode travelling wave structure as the CLIC crab cavity in order to minimise beam loading and mode separation. The position of the crab cavity close to the final focus enhances the effect of transverse wake-fields so effective wake-field damping is required. A damped detuned structure is proposed to suppress and de-cohere the wake-field hence reducing their effect. Design considerations for the CLIC crab cavity will be discussed as well as the proposed high power testing of these structures at SLAC. Design of a crab cavity for CLIC is underway at the Cockcroft Institute in collaboration with SLAC. This effort draws on a large degree of synergy with the ILC crab cavity developed at the Cockcroft Institute and other deflecting structure development at SLAC. A study of phase and amplitude variations in the cavity suggests that the tolerances are very tight and require a 'beyond state of the art' LLRF control system. A study of cavity geometry and its effect on the cavity fields has been performed using Microwave studio. This study has suggested that for our cavity an iris radius between 4-5 mm is optimum with an iris thickness of 2-3 mm based on group velocity and peak fields. A study of the cavity wakefields show that the single bunch wakes are unlikely to be a problem but the short bunch spacing may cause the multi-bunch wakefields to be an issue. This will require some of the modes to be damped strongly so that the wake is damped significantly before any following bunch arrives. Various methods of damping have been investigated and suggest that

  1. X-Band Crab Cavities for the CLIC Beam Delivery System

    Energy Technology Data Exchange (ETDEWEB)

    Burt, G.; Ambattu, P.K.; Dexter, A.C.; Abram, T.; /Cockcroft Inst. Accel. Sci. Tech. /Lancaster U.; Dolgashev, V.; Tantawi, S.; /SLAC; Jones, R.M.; /Cockcroft Inst. Accel. Sci. Tech. /Manchester U.

    2011-11-22

    The CLIC machine incorporates a 20 mrad crossing angle at the IP to aid the extraction of spent beams. In order to recover the luminosity lost through the crossing angle a crab cavity is proposed to rotate the bunches prior to collision. The crab cavity is chosen to have the same frequency as the main linac (11.9942 GHz) as a compromise between size, phase stability requirements and beam loading. It is proposed to use a HE11 mode travelling wave structure as the CLIC crab cavity in order to minimise beam loading and mode separation. The position of the crab cavity close to the final focus enhances the effect of transverse wake-fields so effective wake-field damping is required. A damped detuned structure is proposed to suppress and de-cohere the wake-field hence reducing their effect. Design considerations for the CLIC crab cavity will be discussed as well as the proposed high power testing of these structures at SLAC. Design of a crab cavity for CLIC is underway at the Cockcroft Institute in collaboration with SLAC. This effort draws on a large degree of synergy with the ILC crab cavity developed at the Cockcroft Institute and other deflecting structure development at SLAC. A study of phase and amplitude variations in the cavity suggests that the tolerances are very tight and require a 'beyond state of the art' LLRF control system. A study of cavity geometry and its effect on the cavity fields has been performed using Microwave studio. This study has suggested that for our cavity an iris radius between 4-5 mm is optimum with an iris thickness of 2-3 mm based on group velocity and peak fields. A study of the cavity wakefields show that the single bunch wakes are unlikely to be a problem but the short bunch spacing may cause the multi-bunch wakefields to be an issue. This will require some of the modes to be damped strongly so that the wake is damped significantly before any following bunch arrives. Various methods of damping have been investigated and

  2. Vertex-Detector R&D for CLIC

    CERN Document Server

    Dannheim, D

    2014-01-01

    A detector concept based on hybrid pixel-detector technology is under development for the CLIC vertex detector. It comprises fast, low-power and small-pitch readout ASICs implemented in 65 nm CMOS technology (CLICpix) coupled to ultra-thin sensors (planar or active HV-CMOS) via low-mass interconnects. The power dissipation of the readout chips is reduced by means of power pulsing, allowing for a cooling system based on forced air flow. In this contribution the CLIC vertex-detector requirements are reviewed and the current status of R&D on readout and sensors is presented.

  3. Single Z' production at CLIC based on e^- gamma collisions

    OpenAIRE

    Soa, D. V.; H.N. Long(Institute of Physics, VAST, 10 Dao Tan, Ba Dinh, Hanoi, Vietnam); Binh, D. T.; Khoi, D. P.

    2003-01-01

    We analyze the potential of CLIC based on e- gamma collisions to search for new $Z'$ gauge boson. Single Z' production at e-gamma colliders in two SU(3)_C X SU(3)_L X U(1)_N models: the minimal model and the model with right-handed (RH) neutrinos is studied in detail. Results show that new Z' gauge bosons can be observed at the CLIC, and the cross sections in the model with RH neutrinos are bigger than those in the minimal one.

  4. Beam Loading Compensation in the Main Linac of CLIC

    OpenAIRE

    Schulte, D.; Syratchev, I.

    2000-01-01

    Compensation of multi-bunch beam loading is of great importance in the main linac of the Compact Linear Collider (CLIC). The bunch-to-bunch energy variation has to stay below 1 part in 1000. In CLIC, the RF power is obtained by decelerating a drive beam which is formed by merging a number of short bunch trains. A promising scheme for tackling beam loading in the main linac is based on varying the lengths of the bunch trains in the drive beam. The scheme and its expected performance are presen...

  5. Higgs Physics at the CLIC Electron-Positron Linear Collider

    CERN Document Server

    Roloff, Philipp Gerhard

    2016-01-01

    The Compact Linear Collider (CLIC) is an option for a future $e^+e^-$ collider operating at centre-of-mass energies up to 3 TeV, providing sensitivity to a wide range of new physics phenomena and precision physics measurements at the energy frontier. This paper presents the Higgs physics reach of CLIC operating in three energy stages, $\\sqrt{s} =$ 350 GeV, 1.4 TeV and 3 TeV. The initial stage of operation allows the study of Higgs boson production in Higgsstrahlung ($e^+e^-\\to ZH$) and $WW$-fusion ($e^+e^-\\to H\

  6. A Study of the Beam Physics in the CLIC Drive Beam Decelerator

    CERN Document Server

    Adli, Erik; Stapnes, Steinar

    2009-01-01

    CLIC is a study for a Multi-TeV e+e- linear collider, in which the rf power for the main linacs is extracted from 100 ampere electron drive beams, by the use of specially designed power extraction structures. Up to 90% of the beam energy is extracted from the drive beams along one kilometer long decelerator sectors, rendering the beam transport challenging. We have identified two major challenges for robust beam transport: the significant transverse wakes in the power extraction structures, and the large energy spread induced by the power extraction process. By beam dynamics studies we have qualified power extraction structure designs, leading to the present CLIC baseline structure in which the transverse wakes are sufficiently mitigated. We have further shown that the beam energy spread induced by the deceleration implies that standard 1-to-1 correction might not ensure satisfactory drive beam transport. As alternative, we propose a decelerator orbit correction scheme based on dispersion-free steering and ex...

  7. THERMAL ANALYSIS AND STRUCTURE STUDIES ON THE BLENDS OF LIQUID CRYSTALLINE COPOLYESTERS AND PET, PBT

    Institute of Scientific and Technical Information of China (English)

    XIE Ping; LU Daohui

    1987-01-01

    The apparent uniform blends of liquid crystalline aromatic copolyesters and semiflexible polyesters PET or PBT were obtained by mechanical mixing in the molten state within certain range of composition.The effects of blending with liquid crystalline components on the structure of homopolyester matrix were examined by thermal analysis and X-ray diffraction. These results suggest that the LC component in the blend may possibly be acting as a nucleating agent, or it may induce axial orientation of molecules promoting the local ordering of matrix. For the blends of PET, these influences mainly display in narrowing the width of cold crystalline peak and enhancing the main peak of x-ray diffraction; and for the blends of PBT, the pre-melting crystalline peak was enhanced.

  8. Geometric calibration between PET scanner and structured light scanner

    DEFF Research Database (Denmark)

    Kjer, Hans Martin; Olesen, Oline Vinter; Paulsen, Rasmus Reinhold;

    2011-01-01

    is a structured light scanner placed just above the patient tunnel on the High Resolution Research Tomograph (HRRT, Siemens). It continuously registers point clouds of a part of the patient's face. The relative motion is estimated as the rigid transformation between frames. A geometric calibration...

  9. Photon-Nucleon Collider based on LHC and CLIC

    CERN Document Server

    Aksakal, Husnu; Schulte, Daniel; Zimmermann, Frank

    2005-01-01

    We describe the scheme of a photon-nucleon collider where high energy photons generated by Compton backscattering off a CLIC electron beam, at either 75 GeV or 1.5 TeV are collided with protons or ions stored in LHC. Different design constraints for such a collider are discussed and achievable luminosity performance is estimated.

  10. Grid Interface Design for the Compact Linear Collider (CLIC)

    CERN Document Server

    Jankovic, Maria; Clare, Jon; Wheeler, Pat; Aguglia, Davide

    2015-01-01

    This paper discusses the grid interface challenges for CERN’s proposed Compact Linear Colliders’ (CLIC) klystron modulators, including a 280 MW power system optimisation. The modular multilevel converter is evaluated as a candidate topology for a Medium Voltage grid interface along with a control method for reducing the impact of klystron modulators on the electrical network.

  11. A Versatile Beam Loss Monitoring System for CLIC

    CERN Document Server

    Kastriotou, Maria; Farabolini, Wilfrid; Holzer, Eva Barbara; Nebot Del Busto, Eduardo; Tecker, Frank; Welsch, Carsten

    2016-01-01

    The design of a potential CLIC beam loss monitoring (BLM) system presents multiple challenges. To successfully cover the 48 km of beamline, ionisation chambers and optical fibre BLMs are under investigation. The former fulfils all CLIC requirements but would need more than 40000 monitors to protect the whole facility. For the latter, the capability of reconstructing the original loss position with a multi-bunch beam pulse and multiple loss locations still needs to be quantified. Two main sources of background for beam loss measurements are identified for CLIC. The two-beam accelerator scheme introduces so-called crosstalk, i.e. detection of losses originating in one beam line by the monitors protecting the other. Moreover, electrons emitted from the inner surface of RF cavities and boosted by the high RF gradients may produce signals in neighbouring BLMs, limiting their ability to detect real beam losses. This contribution presents the results of dedicated experiments performed in the CLIC Test Facility to qu...

  12. CLIC a Two-Beam Multi-TeV $e\\pm$ Linear Collider

    CERN Document Server

    Delahaye, J P; Assmann, R W; Becker, F; Bossart, Rudolf; Braun, H; Burkhardt, H; Carron, G; Coosemans, Williame; Corsini, R; D'Amico, T E; Döbert, Steffen; Fartoukh, Stéphane David; Ferrari, A; Geschonke, Günther; Godot, J C; Groening, L; Guignard, Gilbert; Hutchins, S; Jeanneret, J B; Jensen, E; Jowett, John M; Kamitani, T; Millich, Antonio; Pearce, P; Perriollat, F; Pittin, R; Potier, J P; Riche, A; Rinolfi, Louis; Risselada, Thys; Royer, P; Ruggiero, F; Schulte, Daniel; Suberlucq, Guy; Syratchev, I V; Thorndahl, L; Trautner, H; Verdier, A; Wuensch, Walter; Zhou, F; Zimmermann, Frank; Napoly, O

    2000-01-01

    The CLIC study of a high-energy (0.5 - 5 TeV), high-luminosity (1034 - 1035 cm-2 sec-1) e± linear collider is presented. Beam acceleration using high frequency (30 GHz) normal-conducting structures operating at high accelerating fields (150 MV/m) significantly reduces the length and, in consequence, the cost of the linac. Using parameters derived from general scaling laws for linear colliders, the beam stability is shown to be similar to lower frequency designs in spite of the strong wake-field dependency on frequency. A new cost-effective and efficient drive beam generation scheme for RF power production by the so-called "Two-Beam Acceleration" method is described. It uses a thermionic gun and a fully-loaded normal-conducting linac operating at low frequency (937 MHz) to generate and accelerate the drive beam bunches, and RF multiplication by funnelling in compressor rings to produce the desired bunch structure. Recent 30 GHz hardware developments and CLIC Test Facility (CTF) results are described.

  13. Preliminary Design of a Bunching System for the CLIC Polarized Electron Source

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Feng

    2009-10-30

    Major parameters of the CLIC and ILC electron sources are given in Table I. It is shown that the CLIC source needs to provide 312 15-ps-long 2-GHz microbunches. There are two approaches to achieve the time structure [2]: one is to develop a 2-GHz optical pulse train, and the other to develop a 156-ns-long CW optical pulse and use an RF bunching system to generate 312 2-GHz microbunches. The former scheme may ease the RF bunching system but still need it to bunch 100-ps of microbunch down to 15-ps level. Otherwise, a huge amount of energy spread is accumulated when the beam is accelerated through downstream 2-GHz accelerator. In addition, in the former scheme, the space charge is high and surface charge is not yet proven in the parameter regime and 2-GHz mode locked laser is challenging. The latter scheme needs a high-efficiency bunching system to generate 312 15-ps microbunches with 2-GHz repetition rate but it has some notable advantages: a 156-ns CW laser technique is matured, and the charge limit behavior in the scheme is better characterized than that in the former case, as listed in the table. This note presents a design and modeling of the bunching system for the latter scheme to convert a 156-ns CW pulse to 312 15-ps long 2-GHz microbunches.

  14. CLIC Main Linac Beam-Loading Compensation by Drive Beam Phase Modulation

    CERN Document Server

    Corsini, R; Syratchev, I V

    1999-01-01

    The CLIC final focus momentum acceptance of ± 0.5 % limits the bunch-to-bunch energy variation in the main beam to less than ± 0.1 %, since the estimated single-bunch contribution is ± 0.4 %. On the other hand, a relatively high beam-loading of the main accelerating structures (about 16 %) is unavoidable in order to optimize the RF-to-beam efficiency. Therefore, a compensation method is needed to reduce the resulting bunch-to-bunch energy spread of the main beam. Up to now, it has been planned to obtain the RF pulse shape needed for compensation by means of a charge ramp in the drive beam pulse. On the other hand, the use of constant-current drive beam pulses would make the design and operation of the drive beam injector considerably simpler. In this paper we present a possible solution adapted to the CLIC two-beam scheme with constant-current pulses, based on phase modulation of the drive beam bunches.

  15. Processing of three-dimensional structures of Nuclear Medicine in PET modality; Processamento de estruturas tridimensionais de medicina nuclear na modalidade PET

    Energy Technology Data Exchange (ETDEWEB)

    Pacheco, Edward Florez; Furuie, Sergio Shiguemi, E-mail: edward.florez@usp.br [Universidade de Sao Paulo (EP/USP), SP (Brazil). Dept. de Engenharia de Telecomunicacoes e Controle. Lab. de Engenharia Biomedica

    2013-03-15

    The nuclear medicine, as a specialty to obtain medical images is very important, and it has became one of the main procedures utilized in health care centers to analyze the metabolic behavior of the patient. This project was based on medical images obtained by the PET modality (Positron Emission Tomography). Thus, we developed a framework for processing Nuclear Medicine three-dimensional images of the PET modality, which is composed of consecutive steps that start with the generation of standard images (gold standard) by using simulated images of the Left Ventricular Heart, such as phantoms obtained from the NCAT-4D software. Then, Poisson quantum noise was introduced into the whole volume to simulate the characteristic noises in PET images. Subsequently, the pre-processing step was executed by using specific 3D filters, such as the median filter, the weighted Gaussian filter, and the Anscombe/Wiener filter. Then the segmentation process, which is based on the fuzzy connectedness theory, was implemented. For that purpose four different 3D approaches were implemented: Generic, LIFO, kTetaFOEMS, and dynamic weight algorithm. Finally, an assessment procedure was used as a measurement tool to quantify three parameters (true positive, false positive and maximum distance) that determined the level of efficiency and precision of our process. It was found that the pair filter - segmenter formed by the Anscombe/Wiener filter together with the Fuzzy segmenter based on dynamic weights provided the best results, with VP and FP rates of 98.49 {+-}0.27% and 2.19 {+-}0.19%, respectively, for the simulation of the left ventricular volume. Along with the set of choices made during the processing structure, the project was finished with the analysis of a small number of volumes that belonged to a real PET test, thus the quantification of the volumes was obtained. (author)

  16. Common ground in ILC and CLIC detector concepts

    CERN Multimedia

    Daisy Yuhas

    2013-01-01

    The Compact Linear Collider and the International Linear Collider will accelerate particles and create collisions in different ways. Nonetheless, the detector concepts under development share many commonalities.   Timepix chips under scrutiny in the DESY test beam with the help of the beam telescope. CERN physicist Dominik Dannheim explains that the CLIC detector plans are adaptations of the ILC detector designs with a few select modifications. “When we started several years ago, we did not want to reinvent the wheel,” says Dannheim. “The approved ILC detector concepts served as an excellent starting point for our designs.” Essential differences Both CLIC and ILC scientists foresee general-purpose detectors that make measurements with exquisite precision. These colliders, however, have very different operating parameters, which will have important consequences for the various detector components. The ILC’s collision energy is set at 500 GeV ...

  17. Intra-Beam scattering in the CLIC Damping Rings

    CERN Document Server

    Vivoli, A

    2010-01-01

    The CLIC 3 TeV nominal design requires very low emittance of the electron and positron beams to be reached in the damping rings. Due to low energy and to relatively high bunch charge and ultra-low emittance, Intra-Beam Scattering (IBS) effect is very strong and an accurate calculation is needed to check if the required emittance is effectively reached. For this reason it is being developed at CERN a new software for IBS and Radiation Effects (SIRE), which simulates the evolution of the beam particle distribution in the damping rings, taking into account radiation damping, IBS and quantum excitation. In this paper we present the results of our simulations performed with SIRE on a lattice of the CLIC damping rings.

  18. Initial study on the shape optimisation of the CLIC crab cavity

    CERN Document Server

    Ambattu, P K; Carter, R G; Dexter, A C; Jones, R M; McIntosh, P

    2008-01-01

    The compact linear collider (CLIC) requires a crab cavity to align bunches prior to collision. The bunch structure demands tight amplitude and phase tolerances of the RF fields inside the cavity, for the minimal luminosity loss. Beam loading effects require special attention as it is one potential sources of field errors in the cavity. In order to assist the amplitude and phase control, we propose a travelling wave (TW) structure with a high group velocity allowing rapid propagation of errors out of the system. Such a design makes the cavity structure significantly different from previous ones. This paper will look at the implications of this on other cavity parameters and the optimisation of the cavity geometry.

  19. First phase of CLIC R&D complete

    CERN Multimedia

    Katarina Anthony

    2012-01-01

    Let’s turn back the clocks to 2002: the LHC is still under construction, the wrap-up of the LEP physics programme is still in recent memory and the future of electron-positron accelerators at CERN is ambiguous. It was then that CLIC set out to prove the feasibility of their novel accelerator design in the CTF3 test facility. Though once a tall order for the collaboration, the recently released CLIC Conceptual Design Report has proven many of the major design elements… bringing to an end the first phase of CLIC R&D and pointing toward detailed performance optimisation studies in the next phase.   Streak camera images of the final beam, illustrating the combination of beams in the Combiner Ring. Over a decade ago, the CTF3 team set up shop in the vacated LIL injector site, once home to the weathered machine that delivered electrons and positrons to LEP. Rebuilding and upgrading the machine piece by piece, the CTF3 team converted this mA linac into a high-current drive b...

  20. Sensitivity Analysis for the CLIC Damping Ring Inductive Adder

    CERN Document Server

    Holma, Janne

    2012-01-01

    The CLIC study is exploring the scheme for an electron-positron collider with high luminosity and a nominal centre-of-mass energy of 3 TeV. The CLIC pre-damping rings and damping rings will produce, through synchrotron radiation, ultra-low emittance beam with high bunch charge, necessary for the luminosity performance of the collider. To limit the beam emittance blow-up due to oscillations, the pulse generators for the damping ring kickers must provide extremely flat, high-voltage pulses. The specifications for the extraction kickers of the CLIC damping rings are particularly demanding: the flattop of the output pulse must be 160 ns duration, 12.5 kV and 250 A, with a combined ripple and droop of not more than ±0.02 %. An inductive adder allows the use of different modulation techniques and is therefore a very promising approach to meeting the specifications. PSpice has been utilised to carry out a sensitivity analysis of the predicted output pulse to the value of both individual and groups of circuit compon...

  1. Structure/property development in aPET during large strain, solid phase polymer processing

    Science.gov (United States)

    Martin, Peter; Mohamed, Raja Roslan Raja

    2015-12-01

    Amorphous Polyethylene terephthalate (aPET) is increasingly of interest for the polymer packaging industry due to its blend of excellent mechanical properties and most importantly its ease of recyclability. Among the major commercial polymers it is almost unique in the degree of improvement in mechanical properties that can be obtained through process-induced strain. For many years these unique properties have been very successfully exploited in the injection stretch blow molding process, where it is deliberately stretched to very large strains using extremely high pressures. However, the material is now also being used in much lower pressure processes such as thermoforming where its properties are often not fully exploited. In this work the change in structure and properties of aPET with strain is systematically investigated using a high speed biaxial stretching machine. The aim was to demonstrate how the properties of the material could be controlled by large strain, high temperature biaxial stretching processes such as thermoforming and blow molding. The results show that property changes in the material are driven by orientation and the onset of rapid strain hardening at large strains. This in turn is shown to vary strongly with process-induced parameters such as the strain rate and the mode and magnitude of biaxial deformation.

  2. Swift heavy ion induced modification in PET: Structural and thermal properties

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Virendra [Department of Chemistry, Panjab University, Chandigarh 160 014 (India); Singh, Tejvir [Department of Chemistry, Panjab University, Chandigarh 160 014 (India); Chandra, Amita [Department of Physics, Panjab University, Chandigarh 160 014 (India); Bandyopadhyay, S.K. [Department of Physics, Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Kolkata 700 064 (India)]. E-mail: skband@veccal.ernet.in; Sen, Pintu [Department of Physics, Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Kolkata 700 064 (India); Witte, K. [Aachen University of Applied Sciences, Ginsterweg-1, D-52428 Juelich (Germany); Scherer, U.W. [Aachen University of Applied Sciences, Ginsterweg-1, D-52428 Juelich (Germany); Srivastava, Alok [Department of Chemistry, Panjab University, Chandigarh 160 014 (India); Aachen University of Applied Sciences, Ginsterweg-1, D-52428 Juelich (Germany)

    2006-03-15

    Films of 12 {mu}m thickness of the polymer polyethylene terephthalate (PET) were exposed to swift heavy ions of silicon with energies ranging from 44 MeV to 120 MeV and total ion fluence ranging between 10{sup 11} and 10{sup 13} ions/cm{sup 2}. The structural properties were investigated using Fourier transform infra red (FT-IR) and X-ray diffraction (XRD) techniques whereas the thermal studies were carried out employing differential scanning calorimetry (DSC). It was noticed that in general irradiation of PET by swift heavy ions of silicon led to the transformation of the polymer into a disordered amorphous state. However, at low fluence, some degree of ordering was noticed as reflected from new peak appearing in the XRD pattern. Around 35% decrease in the crystallite size was observed at the highest fluence. The observation of a mixture of different endotherms arising due to series of melting points at lower temperatures gave further evidence to the observation stated above. The results obtained in the present work are discussed in the light of similar studies reported in literature on other polymers irradiated with low and high energy radiations.0.

  3. Swift heavy ion induced modification in PET: Structural and thermal properties

    International Nuclear Information System (INIS)

    Films of 12 μm thickness of the polymer polyethylene terephthalate (PET) were exposed to swift heavy ions of silicon with energies ranging from 44 MeV to 120 MeV and total ion fluence ranging between 1011 and 1013 ions/cm2. The structural properties were investigated using Fourier transform infra red (FT-IR) and X-ray diffraction (XRD) techniques whereas the thermal studies were carried out employing differential scanning calorimetry (DSC). It was noticed that in general irradiation of PET by swift heavy ions of silicon led to the transformation of the polymer into a disordered amorphous state. However, at low fluence, some degree of ordering was noticed as reflected from new peak appearing in the XRD pattern. Around 35% decrease in the crystallite size was observed at the highest fluence. The observation of a mixture of different endotherms arising due to series of melting points at lower temperatures gave further evidence to the observation stated above. The results obtained in the present work are discussed in the light of similar studies reported in literature on other polymers irradiated with low and high energy radiations

  4. Long Span DNA Paired-End-Tag (DNA-PET) Sequencing Strategy for the Interrogation of Genomic Structural Mutations and Fusion-Point-Guided Reconstruction of Amplicons

    OpenAIRE

    Yao, Fei; Ariyaratne, Pramila N.; Hillmer, Axel M.; Lee, Wah Heng; Li, Guoliang; Teo, Audrey S. M.; Woo, Xing Yi; Zhang, Zhenshui; Chen, Jieqi P.; Poh, Wan Ting; Zawack, Kelson F. B.; Chan, Chee Seng; Leong, See Ting; Neo, Say Chuan; Choi, Poh Sum D.

    2012-01-01

    Structural variations (SVs) contribute significantly to the variability of the human genome and extensive genomic rearrangements are a hallmark of cancer. While genomic DNA paired-end-tag (DNA-PET) sequencing is an attractive approach to identify genomic SVs, the current application of PET sequencing with short insert size DNA can be insufficient for the comprehensive mapping of SVs in low complexity and repeat-rich genomic regions. We employed a recently developed procedure to generate PET s...

  5. Scalar leptoquark production at TESLA and CLIC based eγ colliders

    International Nuclear Information System (INIS)

    We study scalar leptoquark production at TESLA and CLIC based eγ colliders. Both direct and resolved contributions to the cross section are examined. We find that the masses of scalar leptoquarks can be probed up to about 0.9 TeV at TESLA and 2.6 TeV at CLIC. (orig.)

  6. Scalar leptoquark production at TESLA and CLIC based e-gamma colliders

    OpenAIRE

    Cakir, O.; Ateser, E.; Koru, H.

    2002-01-01

    We study scalar leptoquark production at TESLA and CLIC based e-gamma colliders. Both direct and resolved contributions to the cross section are examined. We find that the masses of scalar leptoquarks can be probed up to about 0.9 TeV at TESLA and 2.6 TeV at CLIC.

  7. Online Resources for High School Teachers--A CLIC Away

    Science.gov (United States)

    Holmes, Jon L.

    2000-04-01

    "I'm a high school teacher. I don't have time to sift through all of JCE to find what I need. I don't have enough time as it is!" If you need to find things in a hurry, go to JCE HS CLIC, the JCE High School Chemed Learning Information Center, http://JChemEd.chem.wisc.edu/HS/. You will find good solid, reliable information, and you will find it fast. CLIC is open 24 hours every day, all over the world. What You Will Find at JCE CLIC We know teachers are pressed for time. During the few minutes between classes or at the end of the day, information needs to be found very quickly. Perhaps you are looking for a demo that illustrates electrochemistry using Cu, Mg, orange juice, and a clock; or a student activity on chromatography that is ready to copy and hand out; or a video to illustrate the action of aqua regia on gold, because you can't use aqua regia and can't afford gold. You can find each of these quickly at CLIC. The Journal has always provided lots of articles designed with high school teachers in mind. What the new JCE HS CLIC does is collect the recent materials at one address on JCE Online, making it quicker and easier for you to find them. Information has been gathered from both print and online versions of the Journal, from JCE Software, and from JCE Internet. It is organized as shown at the bottom of the page. Getting Access to Information You have located something that interests you, perhaps a list of tested demonstrations that pertain to consumer chemistry. Now it is time to get it. JCE subscribers (individuals and libraries) can read, download, and print the full versions of the articles as well as all supplemental materials, including student handouts and instructor's notes. You will need the username and password that are on the mailing label that comes with your Journaleach month. JCE HS CLIC home page: http://JChemEd.chem.wisc.edu/HS/ Your Suggestions, Please Our plans for JCE HS CLIC do not end with what you find now. Other resources and features

  8. Experience on Fabrication and Assembly of the First CLIC Two-Beam Module Prototype

    CERN Document Server

    Gudkov, D; Riddone, G; Rossi, F; Lebet, S

    2013-01-01

    The CLIC two-beam module prototypes are intended to prove the design of all technical systems under the different operation modes. Two validation programs are currently under way and they foresee the construction of four prototype modules for mechanical tests without beam and three prototype modules for tests with RF and beam. The program without beam will show the capability of the technical solutions proposed to fulfil the stringent requirements on radio-frequency, supporting, pre-alignment, stabilization, vacuum and cooling systems. The engineering design was performed with the use of CAD/CAE software. Dedicated mock-ups of RF structures, with all mechanical interfaces and chosen technical solutions, are used for the tests and therefore reliable results are expected. The components were fabricated by applying different technologies and methods for manufacturing and joining. The first full-size prototype module was assembled in 2012. This paper is focused on the production process including the comparison o...

  9. Recent results with HV-CMOS and planar sensors for the CLIC vertex detector

    CERN Document Server

    AUTHOR|(SzGeCERN)734627

    2016-01-01

    The physics aims for the future multi-TeV e+e- Compact Linear Collider (CLIC) impose high precision requirements on the vertex detector which has to match the experimental conditions, such as the time structure of the collisions and the presence of beam-induced backgrounds. The principal challenges are: a point resolution of 3μm, 10 ns time stamping capabilities, low mass (⇠0.2% X0 per layer), low power dissipation and pulsed power operation. Recent results of test beam measurements and GEANT4 simulations for assemblies with Timepix3 ASICs and thin active-edge sensors are presented. The 65 nm CLICpix readout ASIC with 25μm pitch was bump bonded to planar silicon sensors and also capacitively coupled through a thin layer of glue to active HV-CMOS sensors. Test beam results for these two hybridisation concepts are presented.

  10. Imperfection Tolerances For On-line Dipsersion Free Steering in the Main LINAC of CLIC

    CERN Document Server

    Pfingstner, J; Schulte, D

    2013-01-01

    Long-term ground motion misaligns the elements of the main linac of CLIC over time. Especially the misaligned quadrupoles create dispersion and hence the beam quality is decreased gradually due to an effect called chromatic dilution. Over longer time periods, orbit feedback systems are not capable to fully recover the beam quality and have to be supplemented by dispersion correction algorithms. In this paper, such and dispersion correction algorithm is presented, which is an extended version of the well-known dispersion free steering algorithm. This extended algorithm can recover the beam quality over long time scaled without stopping the accelerator operation (on-line). Tolerances for different imperfections of the system have been identified and a strong sensitivity to the resolution of the wake field monitors of the main linac accelerating structures has been identified. This problem can be mitigated by using a local excitation scheme as will be shown in this work.

  11. Beam dynamic simulation and optimization of the CLIC positron source and the capture linac

    Science.gov (United States)

    Bayar, C.; Doebert, S.; Ciftci, A. K.

    2016-03-01

    The CLIC Positron Source is based on the hybrid target composed of a crystal and an amorphous target. Simulations have been performed from the exit of the amorphous target to the end of pre-injector linac which captures and accelerates the positrons to an energy of 200 MeV. Simulations are performed by the particle tracking code PARMELA. The magnetic field of the AMD is represented in PARMELA by simple coils. Two modes are applied in this study. The first one is accelerating mode based on acceleration after the AMD. The second one is decelerating mode based on deceleration in the first accelerating structure. It is shown that the decelerating mode gives a higher yield for the e+ beam in the end of the Pre-Injector Linac.

  12. High power X-band RF test stand development and high power testing of the CLIC crab cavity

    OpenAIRE

    Woolley, Benjamin

    2015-01-01

    This thesis describes the development and operation of multiple high power X-band RF test facilities for high gradient acceleration and deflecting structures at CERN, as re-quired for the e+ e- collider research programme CLIC (Compact Linear Collider). Signif-icant improvements to the control system and operation of the first test stand, Xbox-1 are implemented. The development of the second X-band test stand at CERN, Xbox-2 is followed from inception to completion. The LLRF (Low Level Radio ...

  13. CLIC5A, a component of the ezrin-podocalyxin complex in glomeruli, is a determinant of podocyte integrity.

    Science.gov (United States)

    Wegner, Binytha; Al-Momany, Abass; Kulak, Stephen C; Kozlowski, Kathy; Obeidat, Marya; Jahroudi, Nadia; Paes, John; Berryman, Mark; Ballermann, Barbara J

    2010-06-01

    The chloride intracellular channel 5A (CLIC5A) protein, one of two isoforms produced by the CLIC5 gene, was isolated originally as part of a cytoskeletal protein complex containing ezrin from placental microvilli. Whether CLIC5A functions as a bona fide ion channel is controversial. We reported previously that a CLIC5 transcript is enriched approximately 800-fold in human renal glomeruli relative to most other tissues. Therefore, this study sought to explore CLIC5 expression and function in glomeruli. RT-PCR and Western blots show that CLIC5A is the predominant CLIC5 isoform expressed in glomeruli. Confocal immunofluorescence and immunogold electron microscopy reveal high levels of CLIC5A protein in glomerular endothelial cells and podocytes. In podocytes, CLIC5A localizes to the apical plasma membrane of foot processes, similar to the known distribution of podocalyxin and ezrin. Ezrin and podocalyxin colocalize with CLIC5A in glomeruli, and podocalyxin coimmunoprecipitates with CLIC5A from glomerular lysates. In glomeruli of jitterbug (jbg/jbg) mice, which lack the CLIC5A protein, ezrin and phospho-ERM levels in podocytes are markedly lower than in wild-type mice. Transmission electron microscopy reveals patchy broadening and effacement of podocyte foot processes as well as vacuolization of glomerular endothelial cells. These ultrastructural changes are associated with microalbuminuria at baseline and increased susceptibility to adriamycin-induced glomerular injury compared with wild-type mice. Together, the data suggest that CLIC5A is required for the development and/or maintenance of the proper glomerular endothelial cell and podocyte architecture. We postulate that the interaction between podocalyxin and subjacent filamentous actin, which requires ezrin, is compromised in podocytes of CLIC5A-deficient mice, leading to dysfunction under unfavorable genetic or environmental conditions. PMID:20335315

  14. Interaction Point Backgrounds from the CLIC Post Collision Line

    OpenAIRE

    Salt, Michael David

    2012-01-01

    The proposed CLIC accelerator is designed to collide electrons and positrons ata centre of mass energy of 3 TeV, and a luminosity of 5.9 x 10^(34) cm^(−2) s^(−1) at the interactionpoint (IP). Being a single-pass machine, luminosity must be maximised byminimising the beam spot size to the order of a few nanometres. The effects of the finalfocussing and the intense beam-beam effects lead to a high production cross sectionof beamstrahlung photons, and highly divergent outgoing beams, both spatia...

  15. A prototype hybrid pixel detector ASIC for the CLIC experiment

    CERN Document Server

    Valerio, P; Arfaoui, S; Ballabriga, R; Benoit, M; Bonacini, S; Campbell, M; Dannheim, D; De Gaspari, M; Felici, D; Kulis, S; Llopart, X; Nascetti, A; Poikela, T; Wong, W S

    2014-01-01

    A prototype hybrid pixel detector ASIC specifically designed to the requirements of the vertex detector for CLIC is described and first electrical measurements are presented. The chip has been designed using a commercial 65 nm CMOS technology and comprises a matrix of 64x64 square pixels with 25 μm pitch. The main features include simultaneous 4-bit measure- ment of Time-over-Threshold (ToT) and Time-of-Arrival (ToA) with 10 ns accuracy, on-chip data compression and power pulsing capability.

  16. R&D for the Vertexing at CLIC

    CERN Document Server

    Redford, S

    2015-01-01

    The Compact Linear Collider is a candidate to be the next high-energy particle physics collider. Using a novel acceleration technique, electrons and positrons would be brought into collision with a centre-of-mass energy of up to 3 TeV. Despite challenging levels of beam-induced background, this would provide a relatively clean environment in which to perform precision physics measurements. The vertex detector would be crucial in achieving this, and would need to provide accurate particle tracking information to facilitate secondary vertex reconstruction and jet flavour-tagging. With this goal in mind, current technological limits are being stretched to design a low occupancy, low mass and low-power dissipation vertex detector for CLIC. A concept comprising thin hybrid pixel detectors coupled to high- performance readout ASICs, power-pulsing and air-flow cooling is under development. In this paper, the CLIC vertex detector requirements are reviewed and the current status of R&D on sensors, readout, powerin...

  17. Preliminary Design of an Inductive Adder for CLIC Damping Rings

    CERN Document Server

    Holma, J

    2011-01-01

    The Compact Linear Collider (CLIC) study is exploring the scheme for an electron-positron collider with high luminosity and a nominal centre-of-mass energy of 3 TeV. The CLIC damping rings will produce ultra-low emittance beam, with high bunch charge, necessary for the luminosity performance of the collider. To limit the beam emittance blow-up due to oscillations, the pulse power modulators for the damping rings kickers must provide extremely flat, high-voltage, pulses: specifications call for a 160 ns duration flattop of 12.5 kV, 250 A, with a combined ripple and droop of not more than ±0.02 %. A solid-state modulator, the inductive adder, is a very promising approach to meeting the demanding specifications; this topology allows the use of both digital and analogue modulation. To effectively use modulation techniques to achieve such low ripple and droop requires an in-depth knowledge of the behaviour of the solid-state switching components and their gate drivers, as well as a good understanding of the overa...

  18. Brilliant positron sources for CLIC and other collider projects

    CERN Document Server

    Rinolfi, Louis; Dadoun, Olivier; Kamitani, Takuya; Strakhovenko, Vladimir; Variola, Alessandro

    2013-01-01

    The CLIC (Compact Linear Collider), as future linear collider, requires an intense positron source. A brief history is given up to the present baseline configuration which assumes unpolarized beams. A conventional scheme, with a single tungsten target as source of e-e+ pairs, has been studied several years ago. But, in order to reduce the beam energy deposition on the e+ target converter, a double-target system has been studied and proposed as baseline for CLIC. With this ‘‘hybrid target’’, the positron production scheme is based on the channeling process. A 5 GeV electron beam impinges on a thin crystal tungsten target aligned along its axis, enhancing the photon production by channeling radiation. A large number of photons are sent to a thick amorphous tungsten target, generating large number of e-e+ pairs, while the charged particles are bent away, reducing the deposited energy and the PEDD (Peak Energy Deposition Density). The targets parameters are optimized for the positron production. Polarize...

  19. Higgs Physics at the CLIC Electron-Positron Linear Collider

    CERN Document Server

    Abramowicz, H; Afanaciev, K; Tehrani, N Alipour; Balázs, C; Benhammou, Y; Benoit, M; Bilki, B; Blaising, J -J; Boland, M J; Boronat, M; Borysov, O; Božović-Jelisavčić, I; Buckland, M; Bugiel, S; Burrows, P N; Charles, T K; Daniluk, W; Dannheim, D; Dasgupta, R; Demarteau, M; Gutierrez, M A Díaz; Eigen, G; Elsener, K; Felzmann, U; Firlej, M; Firu, E; Fiutowski, T; Fuster, J; Gabriel, M; Gaede, F; García, I; Ghenescu, V; Goldstein, J; Green, S; Grefe, C; Hauschild, M; Hawkes, C; Hynds, D; Idzik, M; Kačarević, G; Kalinowski, J; Kananov, S; Klempt, W; Kopec, M; Krawczyk, M; Krupa, B; Kucharczyk, M; Kulis, S; Laštovička, T; Lesiak, T; Levy, A; Levy, I; Linssen, L; Lukić, S; Maier, A A; Makarenko, V; Marshall, J S; Mei, K; Milutinović-Dumbelović, G; Moroń, J; Moszczyński, A; Moya, D; Münker, R M; Münnich, A; Neagu, A T; Nikiforou, N; Nikolopoulos, K; Nürnberg, A; Pandurović, M; Pawlik, B; Codina, E Perez; Peric, I; Petric, M; Pitters, F; Poss, S G; Preda, T; Protopopescu, D; Rassool, R; Redford, S; Repond, J; Robson, A; Roloff, P; Ros, E; Rosenblat, O; Ruiz-Jimeno, A; Sailer, A; Schlatter, D; Schulte, D; Shumeiko, N; Sicking, E; Simon, F; Simoniello, R; Sopicki, P; Stapnes, S; Ström, R; Strube, J; Świentek, K P; Szalay, M; Tesař, M; Thomson, M A; Trenado, J; Uggerhøj, U I; van der Kolk, N; van der Kraaij, E; Pinto, M Vicente Barreto; Vila, I; Gonzalez, M Vogel; Vos, M; Vossebeld, J; Watson, M; Watson, N; Weber, M A; Weerts, H; Wells, J D; Weuste, L; Winter, A; Wojtoń, T; Xia, L; Xu, B; Żarnecki, A F; Zawiejski, L; Zgura, I -S

    2016-01-01

    The Compact Linear Collider (CLIC) is an option for a future e+e- collider operating at centre-of-mass energies up to 3 TeV, providing sensitivity to a wide range of new physics phenomena and precision physics measurements at the energy frontier. This paper presents the Higgs physics reach of CLIC operating in three energy stages, sqrt(s) = 350 GeV, 1.4 TeV and 3 TeV. The initial stage of operation allows the study of Higgs boson production in Higgsstrahlung (e+e- -> ZH) and WW-fusion (e+e- -> Hnunu), resulting in precise measurements of the production cross sections, the Higgs total decay width Gamma_H, and model-independent determinations of the Higgs couplings. Operation at sqrt(s) > 1 TeV provides high-statistics samples of Higgs bosons produced through WW-fusion, enabling tight constraints on the Higgs boson couplings. Studies of the rarer processes e+e- -> ttH and e+e- -> HHnunu would allow measurements of the top Yukawa coupling and the Higgs boson self-coupling. This paper presents detailed studies of...

  20. Feasibility study of multipoint based laser alignment system for CLIC

    CERN Document Server

    Stern, G; Mainaud-Durand, H; Piedigrossi, D; Geiger, A

    2012-01-01

    CLIC (Compact LInear Collider) is a study for a future electron-positron collider that would allow physicists to explore a new energy region beyond the capabilities oftoday’s particle accelerators. Alignment is one of the major challenges within the CLIC study in order to achieve the high requirement of a multi-TeV center of mass colliding beam energy range (nominal 3 TeV). To reach this energy in a realistic and cost efficient scenario all accelerator components have to be aligned with an accuracy of 10 μm over a sliding window of 200 m. The demand for a straight line reference is so far based on stretched wires coupled with Wire Positioning Sensors (WPS). These solutions are currently further developed inorder to reduce the drawbacks which are mainly given by their costs and difficult implementation. However, it should be validated through inter-comparison with a solution ideally based on a different physical principle. Therefore, a new metrological approach is proposed using a laser beam as straight lin...

  1. The CLIC positron source based on compton schemes

    CERN Document Server

    Rinolfi, L; Braun, H; Papaphilippou, Y; Schulte, D; Vivoli, A; Zimmermann, F; Dadoun, O; Lepercq, P; Roux, R; Variola, A; Zomer, F; Pogorelski, I; Yakimenko, V; Gai, W; Liu, W; Kamitani, T; Omori, T; Urakawa, J; Kuriki, M; Takahasi, TM; Bulyak, E; Gladkikh, P; Chehab, R; Clarke, J

    2010-01-01

    The CLIC polarized positron source is based on a positron production scheme in which polarized photons are produced by a Compton process. In one option, Compton backscattering takes place in a so-called “Compton ring”, where an electron beam of 1 GeV interacts with circularly-polarized photons in an optical resonator. The resulting circularly-polarized gamma photons are sent on to an amorphous target, producing pairs of longitudinally polarized electrons and positrons. The nominal CLIC bunch population is 4.2x109 particles per bunch at the exit of the Pre-Damping Ring (PDR). Since the photon flux coming out from a "Compton ring" is not sufficient to obtain the requested charge, a stacking process is required in the PDR. Another option is to use a Compton Energy Recovery Linac (ERL) where a quasicontinual stacking in the PDR could be achieved. A third option is to use a "Compton Linac" which would not require stacking. We describe the overall scheme as well as advantages and constraints of the three option...

  2. Ground Motion Mitigation in the Main Linac of CLIC

    International Nuclear Information System (INIS)

    Full text: The future linear collider CLIC (Compact Linear Collider) is CERN's propose for a successor of the LHC (Large Hadron Collider). The design of CLIC requires ultralow particle beam emittances, which makes the accelerator very sensitive to ground motion. Without countermeasure, the beam quality would be already unacceptable after a few seconds. In our work we present a feedback algorithm, which mitigates the parasitic effects of ground motion in the main linac of CLIC efficiently. We use an adaptive controller, which is composed of two parts: a system identification unit and a SVD control algorithm. The system identification unit calculates on-line estimates of the time changing accelerator behaviour. This precise model, which can adapt to system changes, is used by the control algorithm. If the system identification unit would not be used, drifting accelerator parameter would cause a mismatch between the real accelerator behaviour and the model used by the controller, which would result in a poor controller performance. Standard system identification algorithms cannot be used in an accelerator environment. The indispensable system excitation cause a not tolerable emittance growth, if it is applied thoughtless. Instead a special excitation scheme consisting of interleaved beam bumps was implemented, which keeps the emittance growth at an acceptable level. However, this special excitation has the disadvantage that not the complete system can be identified anymore. To still get an all over model of the system, we use the identification data and interpolate them with the help of a beam oscillation amplitude model, derived for the main linac of CLIC. The control algorithm uses the identified system data, which are the orbit response matrix R. With the help of the SVD decomposition of R, a very efficient filter can be created. This filter reconstructs the ground motion components, which are causing the majority of the emittance growth. At the same time the

  3. X-ray crystal structure of the passenger domain of plasmid encoded toxin(Pet), an autotransporter enterotoxin from enteroaggregative Escherichia coli (EAEC)

    Energy Technology Data Exchange (ETDEWEB)

    Domingo Meza-Aguilar, J. [Departamento de Salud Pública Facultad de Medicina UNAM, Ciudad Universitaria Coyoacán 04510, D.F. (Mexico); Laboratorio de Patogenicidad Bacteriana, Unidad de Hemato Oncología e Investigación, Hospital Infantil de México Federico Gómez 06720, D.F. (Mexico); Fromme, Petra [Department of Chemistry and Biochemistry, Arizona State University, Physical Sciences BLDG D-102, Tempe, AZ 85287 (United States); Torres-Larios, Alfredo [Instituto de Fisiología Celular UNAM, Ciudad Universitaria Coyoacán 04510, D.F. (Mexico); Mendoza-Hernández, Guillermo [Instituto de Química UNAM, Ciudad Universitaria Coyoacán 04510, D.F (Mexico); Hernandez-Chiñas, Ulises [Departamento de Salud Pública Facultad de Medicina UNAM, Ciudad Universitaria Coyoacán 04510, D.F. (Mexico); Laboratorio de Patogenicidad Bacteriana, Unidad de Hemato Oncología e Investigación, Hospital Infantil de México Federico Gómez 06720, D.F. (Mexico); Arreguin-Espinosa de los Monteros, Roberto A. [Instituto de Química UNAM, Ciudad Universitaria Coyoacán 04510, D.F (Mexico); and others

    2014-03-07

    Highlights: • X-ray crystal structure of the passenger domain of Plasmid encoded toxin at 2.3 Å. • Structural differences between Pet passenger domain and EspP protein are described. • High flexibility of the C-terminal beta helix is structurally assigned. - Abstract: Autotransporters (ATs) represent a superfamily of proteins produced by a variety of pathogenic bacteria, which include the pathogenic groups of Escherichia coli (E. coli) associated with gastrointestinal and urinary tract infections. We present the first X-ray structure of the passenger domain from the Plasmid-encoded toxin (Pet) a 100 kDa protein at 2.3 Å resolution which is a cause of acute diarrhea in both developing and industrialized countries. Pet is a cytoskeleton-altering toxin that induces loss of actin stress fibers. While Pet (pdb code: 4OM9) shows only a sequence identity of 50% compared to the closest related protein sequence, extracellular serine protease plasmid (EspP) the structural features of both proteins are conserved. A closer structural look reveals that Pet contains a β-pleaded sheet at the sequence region of residues 181–190, the corresponding structural domain in EspP consists of a coiled loop. Secondary, the Pet passenger domain features a more pronounced beta sheet between residues 135 and 143 compared to the structure of EspP.

  4. X-ray crystal structure of the passenger domain of plasmid encoded toxin(Pet), an autotransporter enterotoxin from enteroaggregative Escherichia coli (EAEC)

    International Nuclear Information System (INIS)

    Highlights: • X-ray crystal structure of the passenger domain of Plasmid encoded toxin at 2.3 Å. • Structural differences between Pet passenger domain and EspP protein are described. • High flexibility of the C-terminal beta helix is structurally assigned. - Abstract: Autotransporters (ATs) represent a superfamily of proteins produced by a variety of pathogenic bacteria, which include the pathogenic groups of Escherichia coli (E. coli) associated with gastrointestinal and urinary tract infections. We present the first X-ray structure of the passenger domain from the Plasmid-encoded toxin (Pet) a 100 kDa protein at 2.3 Å resolution which is a cause of acute diarrhea in both developing and industrialized countries. Pet is a cytoskeleton-altering toxin that induces loss of actin stress fibers. While Pet (pdb code: 4OM9) shows only a sequence identity of 50% compared to the closest related protein sequence, extracellular serine protease plasmid (EspP) the structural features of both proteins are conserved. A closer structural look reveals that Pet contains a β-pleaded sheet at the sequence region of residues 181–190, the corresponding structural domain in EspP consists of a coiled loop. Secondary, the Pet passenger domain features a more pronounced beta sheet between residues 135 and 143 compared to the structure of EspP

  5. Structural, electrical and optical properties of Ga-doped ZnO films on PET substrate

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Byeong-Guk; Kim, Jeong-Yeon; Lee, Seok-Jin [Department of Electronic Engineering, Chungju National University, 72 Daehak-ro, Chungju, Chungbuk 380-702 (Korea, Republic of); Park, Jae-Hwan, E-mail: pjh@cjnu.ac.kr [Department of Electronic Engineering, Chungju National University, 72 Daehak-ro, Chungju, Chungbuk 380-702 (Korea, Republic of); Lim, Dong-Gun [Department of Electronic Engineering, Chungju National University, 72 Daehak-ro, Chungju, Chungbuk 380-702 (Korea, Republic of); Park, Mun-Gi [Process Development Team 3, LG Display Co. Ltd., 1007, Deogeun-ri, Wollong-myeon, Paju Gyeonggi-do, 413-811 (Korea, Republic of)

    2010-11-15

    The effects of O{sub 2} plasma pretreatment on the properties of Ga-doped ZnO films on PET substrate were studied. Ga-doped ZnO films were fabricated by RF magnetron sputtering process. To improve surface energy and adhesion of PET substrate, O{sub 2} plasma pretreatment process was used prior to GZO sputtering. With increasing O{sub 2} plasma treatment time, the contact angle decreases and the RMS surface roughness increases significantly. The transmittance of GZO films on PET substrate in a wavelength of 550 nm was 70-84%. With appropriate O{sub 2} plasma treatment, the resistivity of GZO films on PET substrate was 3.4 x 10{sup -3} {Omega} cm.

  6. Structural, electrical and optical properties of Ga-doped ZnO films on PET substrate

    International Nuclear Information System (INIS)

    The effects of O2 plasma pretreatment on the properties of Ga-doped ZnO films on PET substrate were studied. Ga-doped ZnO films were fabricated by RF magnetron sputtering process. To improve surface energy and adhesion of PET substrate, O2 plasma pretreatment process was used prior to GZO sputtering. With increasing O2 plasma treatment time, the contact angle decreases and the RMS surface roughness increases significantly. The transmittance of GZO films on PET substrate in a wavelength of 550 nm was 70-84%. With appropriate O2 plasma treatment, the resistivity of GZO films on PET substrate was 3.4 x 10-3 Ω cm.

  7. CLIC Pre-damping and Damping Ring Kickers: Initial Ideas to Achieve Stability Requirements

    CERN Document Server

    Barnes, M J; Uythoven, J

    2010-01-01

    The Compact Linear Collider (CLIC) study is exploring the scheme for an electron-positron collider with high luminosity (1034-1035 cm-2s-1) and a nominal centre-of mass energy of 3 TeV: CLIC would complement LHC physics in the multi-TeV range. The CLIC design relies on the presence of Pre-Damping Rings (PDR) and Damping Rings (DR) to achieve the very low emittance, through synchrotron radiation, needed for the luminosity requirements of CLIC. In order to limit the beam emittance blow-up due to oscillations the combined flat top ripple and droop of the field pulse, for the DR extraction kickers, must be less than 0.02 %. In addition, the allowed beam coupling impedance is also very low: a few Ohms longitudinally and a few MW/m transversally. This paper discusses initial ideas for achieving the demanding requirements for the PDR and DR kickers.

  8. PACMAN – an Innovative Doctoral Programme for CLIC

    CERN Multimedia

    CERN Bulletin

    2013-01-01

    The final network project funded under the European Commission’s Seventh Framework Programme (FP7), Marie Curie Actions, held its kick-off meeting at CERN on 20 November 2013.   PACMAN – a study on Particle Accelerator Components Metrology and Alignment to the Nanometre scale – is in the final stage of recruiting 10 PhD students to do research on beam instrumentation, metrology, micrometric alignment, magnetic measurements, nano-positioning and high-precision engineering. The students will acquire multi-disciplinary expertise in advanced engineering combined with a broad span of transferable skills. “PACMAN gives us the opportunity to attract students to CERN at a key moment in the CLIC study,” said Frédérick Bordry, Head of CERN’s Technology Department. “This is also an ideal opportunity to further develop CERN’s networks with industry and universities.” “The project is...

  9. Capacitively coupled hybrid pixel assemblies for the CLIC vertex detector

    CERN Document Server

    Alipour Tehrani, Niloufar; Benoit, Mathieu; Dannheim, Dominik; Dette, Karola; Hynds, Daniel; Kulis, Szymon; Peric, Ivan; Petric, Marko; Redford, Sophie; Sicking, Eva; Valerio, Pierpaolo

    2015-01-01

    The vertex detector at the proposed CLIC multi-TeV linear e+e- collider must have minimal material content and high spatial resolution, combined with accurate time-stamping to cope with the expected high rate of beam-induced backgrounds. One of the options being considered is the use of active sensors implemented in a commercial high-voltage CMOS process, capacitively coupled to hybrid pixel ASICs. A prototype of such an assembly, using two custom designed chips (CCPDv3 as active sensor glued to a CLICpix readout chip), has been characterised both in the lab and in beam tests at the CERN SPS using 120 GeV/c positively charged hadrons. Results of these characterisation studies are presented both for single and dual amplification stages in the active sensor. Pixel cross-coupling results are also presented, showing the sensitivity to placement precision and planarity of the glue layer.

  10. Wakefield Monitor Experiments with X-Band Accelerating Structures

    CERN Document Server

    Lillestøl, Reidar; Corsini, Roberto; Döbert, Steffen; Farabolini, Wilfrid; Malina, Lukas; Pfingstner, Juergen; Wuensch, Walter

    2015-01-01

    The accelerating structures for CLIC must be aligned with a precision of a few um with respect to the beam trajectory in order to mitigate emittance growth due to transverse wake fields. We report on first results from wake field monitor tests in an X-band structure, with a probe beam at the CLIC Test Facility. The monitors are currently installed in the CLIC Two-Beam Module. In order to fully demonstrate the feasibility of using wakefield monitors for CLIC, the precision of the monitors must be verified using a probe beam while simultaneously filling the structure with high power rf used to drive the accelerating mode. We outline plans to perform such a demonstration in the CLIC Test Facility.

  11. The influence of the structures and compounds of DLC coatings on the barrier properties of PET bottles

    International Nuclear Information System (INIS)

    To reduce the oxygen transmission rate through a polyethylene terephthalate (PET) bottle (an organic plastic) diamond-like carbon (DLC) coatings on the inner surface of the PET bottle were deposited by radio frequency plasma-enhanced chemical vapour deposition (RF-PECVD) technology with C2H2 as the source of carbon and Ar as the diluted gas. As the barrier layer to humidity and gas permeation, this paper analyses the DLC film structure, composition, morphology and barrier properties by Fourier transform infrared, atomic force microscopy, scanning electron microscopy and oxygen transmission rate in detail. From the spectrum, it is found that the DLC film mainly consists of sp3 bonds. The barrier property of the films is significantly relevant to the sp3 bond concentration in the coating, the film thickness and morphology. Additionally, it is found that DLC film deposited in an inductively coupled plasma enhanced capacitively coupled plasma source shows a compact, homogeneous and crack-free surface, which is beneficial for a good gas barrier property in PET bottles. (fluids, plasmas and electric discharges)

  12. Flexible transparent PES/silver nanowires/PET sandwich-structured film for high-efficiency electromagnetic interference shielding.

    Science.gov (United States)

    Hu, Mingjun; Gao, Jiefeng; Dong, Yucheng; Li, Kai; Shan, Guangcun; Yang, Shiliu; Li, Robert Kwok-Yiu

    2012-05-01

    We have developed a kind of high-yield synthesis strategy for silver nanowires by a two-step injection polyol method. Silver nanowires and polyethylene oxide (PEO) (M(w) = 900,000) were prepared in a homogeneous-coating ink. Wet composite films with different thicknesses were fabricated on a PET substrate by drawn-down rod-coating technology. Silver nanowires on PET substrates present a homogeneous distribution under the assistance of PEO. Then PEO was thermally removed in situ at a relatively low temperature attributed to its special thermal behavior under atmospheric conditions. As-prepared metallic nanowire films on PET substrates show excellent stability and a good combination of conductivity and light transmission. A layer of transparent poly(ethersulfones) (PESs) was further coated on silver nanowire networks by the same coating method to prevent the shedding and corrosion of silver nanowires. Sandwich-structured flexible transparent films were obtained and displayed excellent electromagnetic interference (EMI) shielding effectiveness. PMID:22533864

  13. Planned Contributions of The Wcrp Climate and Cryosphere (clic) Project To Mountain Hydrological Studies

    Science.gov (United States)

    Barry, R. G.

    Formal discussions within the World Climate Research Programme (WCRP) since 1997 have addressed the question of the role of the cryosphere in the climate system. An outcome has been the approval in March 2000 of a Science and Co-ordination Plan for a new Climate and Cryosphere (CliC) project by the WCRP Joint Scientific Com- mittee in March 2000. The concept of this plan (WCRP, 2001) and particular topics of concern for high-mountain hydrology are discussed here. The proposed definition of the cryosphere is that portion of the climate system consisting of the world's ice masses and snow deposits. of relevance for mountains are: ice caps and glaciers, sea- sonal snow cover, lake and river ice, and seasonally frozen ground and permafrost. Existing projects both within the framework of the WCRP, as well as of the IGBP are mainly regional and links into the global climate research effort are not sufficiently comprehensive. The WCRP GEWEX project has cryospheric components concerning the high latitude hydrological cycle, but mountain studies are currently only in Ti- bet. Other relevant programs include: the IGBP-BAHC Mountain Research Initiative, Global Land Ice Measurements from Space (GLIMS), and Permafrost and Climate in Europe (PACE), for example. Integration of existing cryospheric projects within a global research structure, together with new efforts addressing current gaps, is re- quired in order to: - enhance links between regional and global climatic components studies, - promote appropriate treatment of cryospheric processes in climate models, and - assemble and make accessible quality controlled, well documented, comprehen- sive and coherent global gridded data sets necessary for driving and validating climate models. The principal scientific questions relating to the cryosphere in mountain re- gions concern: - glacier melt contributions to global sea level change, - the energy and water cycle in regions with land ice, snow cover and frozen ground, - the

  14. Structural and Optical Investigations of Radiation Damage in Transparent PET Polymer Films

    Directory of Open Access Journals (Sweden)

    Shiv Govind Prasad

    2011-01-01

    Full Text Available Effects of gamma irradiation at different doses up to 135 kGy on polyethylene terephthalate (PET polymer films have been investigated by X-ray diffraction (XRD, Fourier transform infrared (FTIR spectroscopy, and ultraviolet-visible (UV-VIS spectroscopy. From XRD analysis, it was found that even at a high dose of gamma irradiation of 135 kGy, crystallinity of the PET samples remain unchanged. However, the FTIR peak at 871 cm−1 (depicting C–H bending mode of out-of-plane vibration and another at 1303 cm−1 (representing C–H bending mode of in-plane vibration disappear for gamma-irradiated PET. In this study, it has also been found that γ-irradiation in air enhances the optical absorption in the wavelength region 320–370 nm. This has been attributed to free radicals being produced in the polymer by the γ-radiation. Further, the free radicals react with oxygen of air to form carbonyl group and hydroxyls. With increasing γ-dose, there is a red shift of the UV—near visible cutoff for PET. XRD and FTIR observations on γ-damage have been correlated.

  15. Pet Health

    Science.gov (United States)

    ... of safety to your life. Before getting a pet, think carefully about which animal is best for your family. What is each family member looking for in a pet? Who will take care of it? Does anyone ...

  16. Pet Health

    Science.gov (United States)

    Pets can add fun, companionship and a feeling of safety to your life. Before getting a pet, think carefully about which animal is best for ... is each family member looking for in a pet? Who will take care of it? Does anyone ...

  17. Crimping performance and morpho structure of PET/PTT conjugated yarn%PET/PTT复合纤维的卷曲性能与形态结构

    Institute of Scientific and Technical Information of China (English)

    郭静; 郑楠; 张欣; 李晓萌

    2011-01-01

    以POY-DT和FDY工艺获得的不同规格、本色和有色PET/PTT复合纤维为研究对象,考察了纤维规格、工艺路线和色母粒对PET/PTT复合纤维的卷缩性能的影响,表征了复合纤维的轴向形态结构与断面结构,研究了纤维力学性能.结果表明,PET/PTT复合纤维的卷曲性能随着线密度的增加而升高,在130 dtex附近达到峰值;本色复合纤维的卷曲收缩率、卷曲模量和弹性恢复率均高于有色复合纤维,而卷曲稳定度和紧缩伸长率则有色纤维较高,POY-DT工艺得到的复合纤维的卷曲收缩率、卷曲模量、紧缩伸长率、卷曲稳定度、断裂强度高于FDY工艺得到的纤维,但其弹性恢复率低于FDY纤维;经过湿热处理后的复合纤维的卷缩半径明显减小,卷缩性能得到提升;通过复合纤维断面SEM照片观察到,PET与PTT两相间界面黏合良好.%PET/PTT conjugated yarn with different specifications and different colors was obtained by POY-DT and FDY process route. The influence of specification, process route and master batch on crimp contraction property of PET/PTT conjugated yarn was investigated and the axial morphostructure, cross section and the mechanical property of the yarn were characterized. As a result, the crimp contraction of PET/PTT conjugated yarn is rised with the increasing linear density and reach its maximum at 130 dtex. The crimp contraction ratio, crimp module and elastic recovery of primary white PET/PTT conjugated yarn was higher than that of blue. The crimp stability and crimp elongation ratio of the blue PET/PTT conjugated yarn was higher than that of the primary white one. The crimp contraction ratio, crimp module, crimp elongation ratio, crimp stability and breaking strength of PET/PTT conjugated yarn obtained from POY-DY process route was higher than that obtained from FDY process route. But the elastic recovery of PET/PTT conjugated yarn obtained from POY-DY process route was lower than that

  18. Correlations between the structure and the morphology of PET-rubber nanocomposites with different additives

    International Nuclear Information System (INIS)

    The influence of different additives: high density polyethylene (HDPE), low density polyethylene (LDPE) and TiO2 nanoparticles on the polyethylene terephthalate (PET)-rubber nanocomposite interface was investigated. The composites obtained by compression moulding from tire rubber and PET bottles' waste were partially heterogeneous and partially compatible, as confirmed by the FTIR measurements. The type of additives and the curing temperature proved to have a strong effect on the interface(s) and surface properties due to the different inter- and intra-molecular bonds between the composites' constituents. The use of HDPE leads to the largest interfacial change, while the samples with LDPE have a higher degree of porosity/roughness. The composites with TiO2 present a more compact polymer surfaces and higher contact angle value with water, at the initial moment. Titania nanoparticles can be used, thus, as a tool for tailoring the composite wettability. By choosing the adequate additive(s), PET-rubber can be compatibilized to obtain good interfacial adhesion and to reduce the interfacial tension between the components.

  19. A New Technique For Information Processing of CLIC Technical Documentation

    CERN Document Server

    Tzermpinos, Konstantinos

    2013-01-01

    The scientific work presented in this paper could be described as a novel, systemic approach to the process of organization of CLIC documentation. The latter refers to the processing of various sets of archived data found on various CERN archiving services in a more friendly and organized way. From physics aspect, this is equal to having an initial system characterized by high entropy, which after some transformation of energy and matter will produce a final system of reduced entropy. However, this reduction in entropy can be considered valid for open systems only, which are sub-systems of grander isolated systems, to which the total entropy will always increase. Thus, using as basis elements from information theory, systems theory and thermodynamics, the unorganized form of data pending to be organized to a higher form, is modeled as an initial open sub-system with increased entropy, which, after the processing of information, will produce a final system with decreased entropy. This systemic approach to the ...

  20. Les mesures de métrologie pour le CLIC

    CERN Document Server

    Cherif, A

    2008-01-01

    Le projet CLIC est en tout point un défi technique majeur ; c?est le cas également pour la mesure dimensionnelle. Quels sont les équipements et les méthodes qui permettent de caractériser les pièces avec une incertitude de mesure aussi réduite que possible, vu les tolérances micrométriques imposées ? Afin de répondre à cette question, une veille technologique a été maintenue sur une longue période. Les acteurs relevants ont été contactés pour bénéficier d?une ouverture sur les dernières avancées dans le domaine. Différentes techniques ont été étudiées et comparées telles que la digitalisation, la tomographie X, la mesure tridimensionnelle. L'assemblage de haute précision des composants est aussi primordial. Sa mise en ?uvre sous un microscope optique ou à l'aide d'une machine tridimensionnelle est en cours d?étude. L'exposé traitera aussi de la mesure de rugosité, un domaine où nous disposons de moyens adaptés aux exigences spécifiques du projet.

  1. The synchro laser system for the CLIC Test Facility

    International Nuclear Information System (INIS)

    The CLIC Test Facility at CERN uses a laser driven 3 GHz electron gun. Considerable effort has been spent to develop a laser system, which meets the requirements of the Test Facility. The laser is based on a diode-pumped ND:YLF mode-locked oscillator. It delivers a 250 MHz train of laser pulses at 1047 nm with a length of 6.6 ps. A phase-locked timing stabilizer is used to synchronize the laser with the rf-gun. One or two pulses are amplified to 10 mJ. The amplifier system is based on a regenerative amplifier and two single pass power amplifiers. A set of harmonic generators deliver laser pulses at 523 nm, 262 nm and optional at 209nm. The measured pulse length after amplification and harmonic generations is 8 ± 2 ps (FWHM). A good pointing stability and a reasonable uniform transverse profile is obtained by relay imaging and spatial filtering. For some experiments, a train of electron bunches is used. A new pulse train generator working at 262 nm was developed to split the laser beam into 12 pulses. The simultaneous amplification of two seed laser pulses gives the possibility to double the number of pulses in the train without the need to add further splitting stages

  2. Capacitively coupled hybrid pixel assemblies for the CLIC vertex detector

    Science.gov (United States)

    Tehrani, N. Alipour; Arfaoui, S.; Benoit, M.; Dannheim, D.; Dette, K.; Hynds, D.; Kulis, S.; Perić, I.; Petrič, M.; Redford, S.; Sicking, E.; Valerio, P.

    2016-07-01

    The vertex detector at the proposed CLIC multi-TeV linear e+e- collider must have minimal material content and high spatial resolution, combined with accurate time-stamping to cope with the expected high rate of beam-induced backgrounds. One of the options being considered is the use of active sensors implemented in a commercial high-voltage CMOS process, capacitively coupled to hybrid pixel ASICs. A prototype of such an assembly, using two custom designed chips (CCPDv3 as active sensor glued to a CLICpix readout chip), has been characterised both in the lab and in beam tests at the CERN SPS using 120 GeV/c positively charged hadrons. Results of these characterisation studies are presented both for single and dual amplification stages in the active sensor, where efficiencies of greater than 99% have been achieved at -60 V substrate bias, with a single hit resolution of 6.1 μm . Pixel cross-coupling results are also presented, showing the sensitivity to placement precision and planarity of the glue layer.

  3. Clinical application of pet

    OpenAIRE

    Francisco Lomeña; Marina Soler

    2005-01-01

    Positron emission tomography (PET) is an imaging modality that gives information on tissue metabolism and functionalism, different from other imaging techniques like computed tomography (CT) and magnetic resonance imaging (MRI), which provide anatomical or structural information. PET has reached its development in biomedical research because of its capacity to use analogous compounds of many endogenous substance as tracers, and to measure, in vivo and in a non-invasive way, their consumption ...

  4. Progressive hearing loss and vestibular dysfunction caused by a homozygous nonsense mutation in CLIC5.

    Science.gov (United States)

    Seco, Celia Zazo; Oonk, Anne M M; Domínguez-Ruiz, María; Draaisma, Jos M T; Gandía, Marta; Oostrik, Jaap; Neveling, Kornelia; Kunst, Henricus P M; Hoefsloot, Lies H; del Castillo, Ignacio; Pennings, Ronald J E; Kremer, Hannie; Admiraal, Ronald J C; Schraders, Margit

    2015-02-01

    In a consanguineous Turkish family diagnosed with autosomal recessive nonsyndromic hearing impairment (arNSHI), a homozygous region of 47.4 Mb was shared by the two affected siblings on chromosome 6p21.1-q15. This region contains 247 genes including the known deafness gene MYO6. No pathogenic variants were found in MYO6, neither with sequence analysis of the coding region and splice sites nor with mRNA analysis. Subsequent candidate gene evaluation revealed CLIC5 as an excellent candidate gene. The orthologous mouse gene is mutated in the jitterbug mutant that exhibits progressive hearing impairment and vestibular dysfunction. Mutation analysis of CLIC5 revealed a homozygous nonsense mutation c.96T>A (p.(Cys32Ter)) that segregated with the hearing loss. Further analysis of CLIC5 in 213 arNSHI patients from mostly Dutch and Spanish origin did not reveal any additional pathogenic variants. CLIC5 mutations are thus not a common cause of arNSHI in these populations. The hearing loss in the present family had an onset in early childhood and progressed from mild to severe or even profound before the second decade. Impaired hearing is accompanied by vestibular areflexia and in one of the patients with mild renal dysfunction. Although we demonstrate that CLIC5 is expressed in many other human tissues, no additional symptoms were observed in these patients. In conclusion, our results show that CLIC5 is a novel arNSHI gene involved in progressive hearing impairment, vestibular and possibly mild renal dysfunction in a family of Turkish origin. PMID:24781754

  5. Detector optimization studies and light Higgs decay into muons at CLIC

    International Nuclear Information System (INIS)

    The Compact Linear Collider (CLIC) is a concept for a future e+e- linear collider with a center-of-mass energy of up to 3 TeV. The design of a CLIC experiment is driven by the requirements related to the physics goals, as well as by the experimental conditions. For example, the short time between two bunch crossings of 0.5 ns and the backgrounds due to beamstrahlung have direct impact on the design of a CLIC experiment. The Silicon Detector (SiD) is one of the concepts currently being discussed as a possible detector for the International Linear Collider (ILC). In this thesis we develop a modified version of the SiD simulation model for CLIC, taking into account the specific experimental conditions. In addition, we developed a software tool to investigate the impact of beam-related backgrounds on the detector by overlaying events from different simulated event samples. Moreover, we present full simulation studies, determining the performance of the calorimeter and tracking systems. We show that the track reconstruction in the all-silicon tracker of SiD is robust in the presence of the backgrounds at CLIC. Furthermore, we investigate tungsten as a dense absorber material for the hadronic calorimeter, which allows for the construction of a compact hadronic calorimeter that fulfills the requirements on the energy resolution and shower containment without a significant increase of the coil radius. Finally, the measurement of the decays of light Higgs bosons into two muons is studied in full simulation. We find that with an integrated luminosity of 2 ab-1, corresponding to 4 years of data taking at CLIC, the respective Higgs branching ratio can be determined with a statistical uncertainty of approximately 15%.

  6. Detector optimization studies and light Higgs decay into muons at CLIC

    Energy Technology Data Exchange (ETDEWEB)

    Grefe, Christian

    2013-09-15

    The Compact Linear Collider (CLIC) is a concept for a future e{sup +}e{sup -} linear collider with a center-of-mass energy of up to 3 TeV. The design of a CLIC experiment is driven by the requirements related to the physics goals, as well as by the experimental conditions. For example, the short time between two bunch crossings of 0.5 ns and the backgrounds due to beamstrahlung have direct impact on the design of a CLIC experiment. The Silicon Detector (SiD) is one of the concepts currently being discussed as a possible detector for the International Linear Collider (ILC). In this thesis we develop a modified version of the SiD simulation model for CLIC, taking into account the specific experimental conditions. In addition, we developed a software tool to investigate the impact of beam-related backgrounds on the detector by overlaying events from different simulated event samples. Moreover, we present full simulation studies, determining the performance of the calorimeter and tracking systems. We show that the track reconstruction in the all-silicon tracker of SiD is robust in the presence of the backgrounds at CLIC. Furthermore, we investigate tungsten as a dense absorber material for the hadronic calorimeter, which allows for the construction of a compact hadronic calorimeter that fulfills the requirements on the energy resolution and shower containment without a significant increase of the coil radius. Finally, the measurement of the decays of light Higgs bosons into two muons is studied in full simulation. We find that with an integrated luminosity of 2 ab{sup -1}, corresponding to 4 years of data taking at CLIC, the respective Higgs branching ratio can be determined with a statistical uncertainty of approximately 15%.

  7. Status of the Stripline Beam Position Monitor developement for the CLIC Drive Beam

    CERN Document Server

    Benot-Morell, A; Wendt, M; Faus-Golfe, A; Nappa, J M; Vilalte, S; Smith, S

    2013-01-01

    In collaboration with SLAC, LAPP and IFIC, a first prototype of a stripline Beam Position Monitor (BPM) for the CLIC Drive Beam and its associated readout electronics has been successfully tested in the CLIC Test Facility linac (CTF3) at CERN. In addition, a modified prototype with downstream terminated striplines is under development to improve the suppression of unwanted RF signal interference. This paper presents the results of the beam tests, and the most relevant aspects for the modified stripline BPM design and its expected improvements.

  8. Energy and Beam-Offset dependence of the Luminosity weighted depolarization for CLIC

    CERN Document Server

    Esberg, Jakob; Uggerhoj, Ulrik; Dalena, Barbara

    2011-01-01

    We report on simulations of e+e- depolarization due to beam-beam effects. These effects are studied for CLIC at 3 TeV, using GUINEA PIG++. We find a strong energy dependence of the luminosity weighted depolarization. In the luminosity peak at CLIC the total luminosity weighted depolarization remains below the one per-mil level. The effect of a vertical offset on the energy dependent depolarization is investigated. The depolarization in the luminosity peak remains below per-cent level even for 5sy offsets.

  9. Experimental tests on the air cooling of the CLIC vertex detector

    CERN Document Server

    Duarte Ramos, Fernando; Nuiry, Francois-Xavier

    2016-01-01

    The strict requirements in terms of material budget for the inner region of the CLIC detector concept require the use of a dry gas for the cooling of the respective sensors. This, in conjunction with the compactness of the inner volumes, poses several challenges for the design of a cooling system that is able to fulfil the required detector specifications. This note summarizes the results obtained from experimental tests on the air cooling of the CLIC vertex detector as well as their comparison with the corresponding computational fluid dynamics simulations.

  10. Highlights from CERN: The CLIC Project for a Future e$^{+}$e$^{−}$ Linear Collider

    CERN Document Server

    Tecker, Frank

    2007-01-01

    A high luminosity ( 10$^{34}$-10$^{35}$ cm$^{2}$/s) linear electron-positron Collider (CLIC) with a nominal centre-of-mass energy of 3 TeV is under study in the framework of an international collaboration of laboratories and institutes, with the aim to provide the HEP community with a new facility for the post LHC era. After a brief introduction of the physics motivation, the CLIC scheme to extend Linear Colliders into the Multi-TeV colliding beam energy range will be described. In the following, the main challenges and the very promising achievements already obtained will be presented.

  11. Physics at the CLIC $e^{+}e^{-}$ Linear Collider - Input to the Snowmass process 2013

    CERN Document Server

    Abramowicz, Halina; Afanaciev, K.; Alexander, G.; Alipour Tehrani, N.; Alonso, O.; Andersen, K.K.; Arfaoui, S.; Balazs, C.; Barklow, T.; Battaglia, M.; Benoit, M.; Bilki, B.; Blaising, J.J.; Boland, M.; Boronat, M.; Bozovic Jelisavcic, I.; Burrows, P.; Chefdeville, M.; Contino, R.; Dannheim, D.; Demarteau, M.; Diaz Gutierrez, M.A.; Dieguez, A.; Duarte Campderros, J.; Eigen, G.; Elsener, K.; Feldman, D.; Felzmann, U.; Firlej, M.; Firu, E.; Fiutowski, T.; Francis, K.; Gaede, F.; Garcia Garcia, I.; Ghenescu, V.; Giudice, G.; Graf, N.; Grefe, C.; Grojean, C.; Gupta, R.S.; Hauschild, M.; Holmestad, H.; Idzik, M.; Joram, C.; Kananov, S.; Karyotakis, Y.; Killenberg, M.; Klempt, W.; Kraml, S.; Krupa, B.; Kulis, S.; Lastovicka, T.; LeBlanc, G.; Levy, A.; Levy, I.; Linssen, L.; Lucaci Timoce, A.; Lukic, S.; Makarenko, V.; Marshall, J.; Martin, V.; Mikkelsen, R.E.; Milutinovic-Dumbelovic, G.; Miyamoto, A.; Monig, K.; Moortgat-Pick, G.; Moron, J.; Munnich, A.; Neagu, A.; Pandurovic, M.; Pappadopulo, D.; Pawlik, B.; Porod, W.; Poss, S.; Preda, T.; Rassool, R.; Rattazzi, R.; Redford, S.; Reichold, A.; Repond, J.; Riemann, S.; Robson, A.; Roloff, P.; Ros, E.; Rosten, J.; Ruiz-Jimeno, A.; Rzehak, H.; Sailer, A.; Schlatter, D.; Schulte, D.; Sefkow, F.; Seidel, K.; Shumeiko, N.; Sicking, E.; Simon, F.; Smith, J.; Soldner, C.; Stapnes, S.; Strube, J.; Suehara, T.; Swientek, K.; Szalay, M.; Tanabe, T.; Tesar, M.; Thamm, A.; Thomson, M.; Trenado Garcia, J.; Uggerhoj, U.I.; van der Kraaij, E.; Vila, I.; Vilella, E.; Villarejo, M.A.; Vogel Gonzalez, M.A.; Vos, M.; Watson, N.; Weerts, H.; Wells, J.D.; Weuste, L.; Wistisen, T.N.; Wootton, K.; Xia, L.; Zawiejski, L.; Zgura, I.S.

    2013-01-01

    This paper summarizes the physics potential of the CLIC high-energy e+e- linear collider. It provides input to the Snowmass 2013 process for the energy-frontier working groups on The Higgs Boson (HE1), Precision Study of Electroweak Interactions (HE2), Fully Understanding the Top Quark (HE3), as well as The Path Beyond the Standard Model -- New Particles, Forces, and Dimensions (HE4). It is accompanied by a paper describing the CLIC accelerator study, submitted to the Frontier Capabilities group of the Snowmass process

  12. Physics at the CLIC e$^{+}$e$^{-}$ Linear Collider -- Input to the Snowmass process 2013

    OpenAIRE

    Abramowicz, Halina; Abusleme, Angel; Battaglia, Marco; Świentek, Krzysztof; Szalay, Marco; Tanabe, Tomohiko; Tesař, Michal; Thamm, Andrea; Thomson, Mark; Garcia, Juan Trenado; Uggerhøj, Ulrik I.; van der Kraaij, Erik; Vila, Iván; Benoit, Mathieu; Vilella, Eva

    2013-01-01

    This paper summarizes the physics potential of the CLIC high-energy e+e- linear collider. It provides input to the Snowmass 2013 process for the energy-frontier working groups on The Higgs Boson (HE1), Precision Study of Electroweak Interactions (HE2), Fully Understanding the Top Quark (HE3), as well as The Path Beyond the Standard Model -- New Particles, Forces, and Dimensions (HE4). It is accompanied by a paper describing the CLIC accelerator study, submitted to the Frontier Capabilities gr...

  13. Lung PET scan

    Science.gov (United States)

    Chest PET scan; Lung positron emission tomography; PET - chest; PET - lung; PET - tumor imaging ... A PET scan requires a small amount of tracer. The tracer is given through a vein (IV), usually on ...

  14. Clinical application of PET

    Energy Technology Data Exchange (ETDEWEB)

    Lomena, Francisco [Hospital Clinico Villarroel, Barcelona (Spain). Nuclear Medicine]. E-mail: flomena@clinic.ub.es; Soler, Marina [CETIR Grup Medic. Esplkugues de Llobregat, Barcelona (Spain). PET Unit

    2005-10-15

    Positron emission tomography (PET) is an imaging modality that gives information on tissue metabolism and functionalism, different from other imaging techniques like computed tomography (CT) and magnetic resonance imaging (MRI), which provide anatomical or structural information. PET has reached its development in biomedical research because of its capacity to use analogous compounds of many endogenous substance as tracers, and to measure, in vivo and in a non-invasive way, their consumption by the different organs and tissues of the mammalian body. Fluorodeoxyglucose-F 18 (FDG) PET has been proven to be a tracer adequate for clinical use in oncology and in many neurological diseases, with an excellent cost-efficiency ratio. The current PET-CT scanners can come to be the best tools for exploring patients who suffer from cancer.(author)

  15. Proposal for an alignment method of the CLIC linear accelerator - From geodesic networks to the active pre-alignment

    International Nuclear Information System (INIS)

    The compact linear collider (CLIC) is the particle accelerator project proposed by the european organization for nuclear research (CERN) for high energy physics after the large hadron collider (LHC). Because of the nano-metric scale of the CLIC leptons beams, the emittance growth budget is very tight. It induces alignment tolerances on the positions of the CLIC components that have never been achieved before. The last step of the CLIC alignment will be done according to the beam itself. It falls within the competence of the physicists. However, in order to implement the beam-based feedback, a challenging pre-alignment is required: 10 μm at 3σ along a 200 m sliding window. For such a precision, the proposed solution must be compatible with a feedback between the measurement and repositioning systems. The CLIC pre-alignment will have to be active. This thesis does not demonstrate the feasibility of the CLIC active pre-alignment but shows the way to the last developments that have to be done for that purpose. A method is proposed. Based on the management of the Helmert transformations between Euclidean coordinate systems, from the geodetic networks to the metrological measurements, this method is likely to solve the CLIC pre-alignment problem. Large scale facilities have been built and Monte-Carlo simulations have been made in order to validate the mathematical modeling of the measurement systems and of the alignment references. When this is done, it will be possible to extrapolate the modeling to the entire CLIC length. It will be the last step towards the demonstration of the CLIC pre-alignment feasibility. (author)

  16. Bounds on the electromagnetic dipole moments through the single top production at the CLIC

    CERN Document Server

    Koksal, M; Gutierrez-Rodriguez, A

    2016-01-01

    We obtain bounds on the anomalous magnetic and electric dipole moments of the $t$-quark from a future high-energy and high-luminosity linear electron positron collider, such as the CLIC, with unpolarized and polarized electron beams which are a powerful tool to determine new physics. We consider the processes $\\gamma e^- \\to \\bar t b\

  17. Benchmarking of the Placet and Dimad tracking codes using the CLIC Post-Collision line

    CERN Document Server

    Ahmed, I; Ferrari, A; Latina, A

    2009-01-01

    In this benchmarking study, two contemporary codes, DIMAD and PLACET, are compared. We consider the 20 mrad post-collision line of the Compact Linear Collider (CLIC) and perform tracking studies of heavily disrupted post-collision electron beams. We successfully find that the two codes provide an equivalent description of the beam transport from the interaction point to the final dump.

  18. First magnetic test of a superconducting Nb$_{3}$Sn Wiggler magnet for CLIC

    CERN Document Server

    Schoerling, D; Fessia, P; Karppinen, M; Mazet, J; Russenschuck, S; Peiffer, P; Grau, A

    2012-01-01

    To achieve high luminosity at the collision point of the Compact Linear Collider (CLIC) the normalized horizontal and vertical emittances of the electron and positron beams must be reduced to 500 nm and4 nm before the beams enter the 1.5 TeV linear accelerators. An effective way to accomplish ultra-low emittances with only small effects on the electron polarization is using damping rings operating at 2.86GeV equipped with superconducting wiggler magnets. Only superconducting wiggler magnets meet the demanding magnetic specifications of the CLIC damping rings. Although Nb-Ti damping wiggler magnets fulfill the specifications of CLIC, Nb3Sn wiggler magnets would reach higher magnetic fields leading to even better beam properties for CLIC. Moreover, they have at the same time higher thermal and magnetic margins. Therefore, Nb3Sn wiggler magnets are under investigation at CERN despite the challenging manufacturing process. This paper presents first results of Nb3Sn coils and short model tests and outlines the fur...

  19. Material and Structural Performance Evaluations of Hwangtoh Admixtures and Recycled PET Fiber-Added Eco-Friendly Concrete for CO2 Emission Reduction

    Directory of Open Access Journals (Sweden)

    Bon-Min Koo

    2014-08-01

    Full Text Available In order to reduce carbon dioxide (CO2 emissions and produce an eco-friendly construction material, a type of concrete that uses a minimal amount of cement, yet still retains equivalent properties to ordinary cement concrete, has been developed and studied all over the world. Hwangtoh, a type of red clay broadly deposited around the world, has traditionally been considered an eco-friendly construction material, with bonus advantages of having health and cost benefits. Presently, Hwangtoh is not commonly used as a modern construction material due to properties such as low strength and high rates of shrinkage cracking. Recent studies, however, have shown that Hwangtoh can be used as a mineral admixture to improve the strength of concrete. In addition, polyethylene terephthalate (PET fibers recycled from PET bottle waste can be used to control shrinkage cracks in Hwangtoh concrete. Therefore, in this study, performance verification is conducted on newly developed Hwangtoh concrete mixed with short recycled PET fibers. The results show that Hwangtoh concrete has compressive strength, elastic modulus, and pH properties that are similar to these features in ordinary cement concrete. The properties of carbonation depth and creep strain of Hwangtoh concrete, however, are larger and smaller, respectively, than in ordinary cement concrete. According to flexural tests, reinforced concrete (RC specimens cast with Hwangtoh admixtures (with and without PET fibers possess similar or better capacities than ordinary RC specimens. The addition of PET fibers significantly improves the structural ductility of RC specimens under normal environmental conditions. However, the implementations of the concrete in aggressive environment must be carefully considered, since a previous study result indicates degradation of its durability performance in aggressive environments, such as seawater [1]. The results of this study validate the possibility of using eco

  20. Innovations in PET/CT

    DEFF Research Database (Denmark)

    Levin Klausen, T; Høgild Keller, S; Vinter Olesen, O;

    2012-01-01

    There has been a longstanding interest in positron emission tomography (PET) in combination with computed tomography (CT). Mostly because of the lack of structural information in PET which makes it difficult to assess the precise location of tissue with metabolic uptake, whereas CT can provide im...

  1. Simultaneous evaluation of brain tumour metabolism, structure and blood volume using [18F]-fluoroethyltyrosine (FET) PET/MRI: feasibility, agreement and initial experience

    International Nuclear Information System (INIS)

    Both [18F]-fluoroethyltyrosine (FET) PET and blood volume (BV) MRI supplement routine T1-weighted contrast-enhanced MRI in gliomas, but whether the two modalities provide identical or complementary information is unresolved. The aims of the study were to investigate the feasibility of simultaneous structural MRI, BV MRI and FET PET of gliomas using an integrated PET/MRI scanner and to assess the spatial and quantitative agreement in tumour imaging between BV MRI and FET PET. A total of 32 glioma patients underwent a 20-min static simultaneous PET/MRI acquisition on a Siemens mMR system 20 min after injection of 200 MBq FET. The MRI protocol included standard structural MRI and dynamic susceptibility contrast (DSC) imaging for BV measurements. Maximal relative tumour FET uptake (TBRmax) and BV (rBVmax), and Dice coefficients were calculated to assess the quantitative and spatial congruence in the tumour volumes determined by FET PET, BV MRI and contrast-enhanced MRI. FET volume and TBRmax were higher in BV-positive than in BV-negative scans, and both VOLBV and rBVmax were higher in FET-positive than in FET-negative scans. TBRmax and rBVmax were positively correlated (R2 = 0.59, p < 0.001). FET and BV positivity were in agreement in only 26 of the 32 patients and in 42 of 63 lesions, and spatial congruence in the tumour volumes as assessed by the Dice coefficients was generally poor with median Dice coefficients exceeding 0.1 in less than half the patients positive on at least one modality for any pair of modalities. In 56 % of the patients susceptibility artefacts in DSC BV maps overlapped the tumour on MRI. The study demonstrated that although tumour volumes determined by BV MRI and FET PET were quantitatively correlated, their spatial congruence in a mixed population of treated glioma patients was generally poor, and the modalities did not provide the same information in this population of patients. Combined imaging of brain tumour metabolism and perfusion using

  2. Simultaneous evaluation of brain tumour metabolism, structure and blood volume using [{sup 18}F]-fluoroethyltyrosine (FET) PET/MRI: feasibility, agreement and initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Henriksen, Otto M.; Hansen, Adam E.; Law, Ian [Copenhagen University Hospital Rigshospitalet Blegdamsvej, Department of Clinical Physiology Nuclear Medicine and PET, Copenhagen (Denmark); Larsen, Vibeke A. [Copenhagen University Hospital Rigshospitalet Blegdamsvej, Department of Radiology, Copenhagen (Denmark); Muhic, Aida; Poulsen, Hans S. [Copenhagen University Hospital Rigshospitalet Blegdamsvej, Department of Oncology, Copenhagen (Denmark); Larsson, Henrik B.W. [Copenhagen University Hospital Rigshospitalet Glostrup, Functional Imaging Unit, Department of Clinical Physiology Nuclear Medicine and PET, Glostrup (Denmark)

    2016-01-15

    Both [{sup 18}F]-fluoroethyltyrosine (FET) PET and blood volume (BV) MRI supplement routine T1-weighted contrast-enhanced MRI in gliomas, but whether the two modalities provide identical or complementary information is unresolved. The aims of the study were to investigate the feasibility of simultaneous structural MRI, BV MRI and FET PET of gliomas using an integrated PET/MRI scanner and to assess the spatial and quantitative agreement in tumour imaging between BV MRI and FET PET. A total of 32 glioma patients underwent a 20-min static simultaneous PET/MRI acquisition on a Siemens mMR system 20 min after injection of 200 MBq FET. The MRI protocol included standard structural MRI and dynamic susceptibility contrast (DSC) imaging for BV measurements. Maximal relative tumour FET uptake (TBR{sub max}) and BV (rBV{sub max}), and Dice coefficients were calculated to assess the quantitative and spatial congruence in the tumour volumes determined by FET PET, BV MRI and contrast-enhanced MRI. FET volume and TBR{sub max} were higher in BV-positive than in BV-negative scans, and both VOL{sub BV} and rBV{sub max} were higher in FET-positive than in FET-negative scans. TBR{sub max} and rBV{sub max} were positively correlated (R{sup 2} = 0.59, p < 0.001). FET and BV positivity were in agreement in only 26 of the 32 patients and in 42 of 63 lesions, and spatial congruence in the tumour volumes as assessed by the Dice coefficients was generally poor with median Dice coefficients exceeding 0.1 in less than half the patients positive on at least one modality for any pair of modalities. In 56 % of the patients susceptibility artefacts in DSC BV maps overlapped the tumour on MRI. The study demonstrated that although tumour volumes determined by BV MRI and FET PET were quantitatively correlated, their spatial congruence in a mixed population of treated glioma patients was generally poor, and the modalities did not provide the same information in this population of patients. Combined

  3. Regulation of the membrane insertion and conductance activity of the metamorphic chloride intracellular channel protein CLIC1 by cholesterol.

    Directory of Open Access Journals (Sweden)

    Stella M Valenzuela

    Full Text Available The Chloride Intracellular ion channel protein CLIC1 has the ability to spontaneously insert into lipid membranes from a soluble, globular state. The precise mechanism of how this occurs and what regulates this insertion is still largely unknown, although factors such as pH and redox environment are known contributors. In the current study, we demonstrate that the presence and concentration of cholesterol in the membrane regulates the spontaneous insertion of CLIC1 into the membrane as well as its ion channel activity. The study employed pressure versus area change measurements of Langmuir lipid monolayer films; and impedance spectroscopy measurements using tethered bilayer membranes to monitor membrane conductance during and following the addition of CLIC1 protein. The observed cholesterol dependent behaviour of CLIC1 is highly reminiscent of the cholesterol-dependent-cytolysin family of bacterial pore-forming proteins, suggesting common regulatory mechanisms for spontaneous protein insertion into the membrane bilayer.

  4. CLIC5 Stabilizes Membrane-Actin Filament Linkages at the Base of Hair Cell Stereocilia in a Molecular Complex with Radixin, Taperin, and Myosin VI

    OpenAIRE

    Salles, Felipe T.; Andrade, Leonardo R.; Tanda, Soichi; Grati, M’hamed; Plona, Kathleen L.; Gagnon, Leona H.; Johnson, Kenneth R.; Kachar, Bechara; Berryman, Mark A.

    2013-01-01

    Chloride intracellular channel 5 protein (CLIC5) was originally isolated from microvilli in complex with actin binding proteins including ezrin, a member of the Ezrin-Radixin-Moesin (ERM) family of membrane-cytoskeletal linkers. CLIC5 concentrates at the base of hair cell stereocilia and is required for normal hearing and balance in mice, but its functional significance is poorly understood. This study investigated the role of CLIC5 in postnatal development and maintenance of hair bundles. Co...

  5. Diabetic Pets

    Science.gov (United States)

    ... health or management, contact your veterinarian. In addition, diabetic pets should be monitored for long-term complications such as cataracts, which commonly develop in diabetic dogs and cats. Other problems that can occur ...

  6. Senior Pets

    Science.gov (United States)

    ... Future AVMA Meeting Dates Meetings & CE Calendar Symposiums & Summits Pet Health Awareness Events About AVMA Who We ... and small dogs are generally considered “senior” at seven years of age. Larger breed dogs tend to ...

  7. Positron Emission Tomography (PET)

    International Nuclear Information System (INIS)

    Positron emission tomography (PET) assesses biochemical processes in the living subject, producing images of function rather than form. Using PET, physicians are able to obtain not the anatomical information provided by other medical imaging techniques, but pictures of physiological activity. In metaphoric terms, traditional imaging methods supply a map of the body's roadways, its, anatomy; PET shows the traffic along those paths, its biochemistry. This document discusses the principles of PET, the radiopharmaceuticals in PET, PET research, clinical applications of PET, the cost of PET, training of individuals for PET, the role of the United States Department of Energy in PET, and the futures of PET. 22 figs

  8. Polyesteramides based on PET

    NARCIS (Netherlands)

    Bouma, Krista

    1999-01-01

    Engineering plastics have good mechanical, thermal and electrical properties, and can be easily processed. Typical engineering plastics include polyamides (PA6,6, PA6, PA4,6) and polyesters (PBT, PET). Compared to polyesters of a similar structure, polyamides have a high glass transition (Tg) and me

  9. Optimal Power System and Grid Interface Design Considerations for the CLICs Klystron Modulators

    CERN Document Server

    Marija, Jankovic; Jon, Clare; Pat, Wheeler; Davide, Aguglia

    2015-01-01

    The Compact Linear Collider (CLIC) is an electron-positron collider under study at CERN with the aim to explore the next generation of high precision/high energy particles physics. The CLIC’s drive beams will be accelerated by approximately 1300 klystrons, requiring highly efficient and controllable solid state capacitor discharge modulators. Capacitor charger specifications include the requirement to mask the pulsed effect of the load from the utility grid, ensure maximum power quality, control the derived DC voltage precisely (to maximize accuracy for the modulators being implemented), and achieve high efficiency and operability of the overall power system. This paper presents the work carried out on the power system interface for the CLIC facility. In particular it discusses the challenges on the utility interface and analysis of the grid interface converters with regards to required functionality, efficiency, and control methodologies.

  10. Stabilization of the Beam Intensity in the Linac at the CTF3 CLIC Test Facility

    CERN Document Server

    Dubrovskiy, A; Bathe, BN; Srivastava, S

    2013-01-01

    A new electron beam stabilization system has been introduced in CTF3 in order to open new possibilities for CLIC beam studies in ultra-stable conditions and to provide a sustainable tool to keep the beam intensity and energy at its reference values for long term operations. The stabilization system is based on a pulse-to-pulse feedback control of the electron gun to compensate intensity deviations measured at the end of the injector and at the beginning of the linac. Thereby it introduces negligible beam distortions at the end of the linac and it significantly reduces energy deviations. A self-calibration mechanism has been developed to automatically configure the feedback controller for the optimum performance. The residual intensity jitter of 0.045% of the stabilized beam was measured whereas the CLIC requirement is 0.075%.

  11. Technologies and R&D for a High Resolution Cavity BPM for the CLIC Main Beam

    CERN Document Server

    Towler, J R; Soby, L; Wendt, M; Boogert, S T; Cullinan, F J; Lyapin, A

    2013-01-01

    The Main Beam (MB) linac of the Compact Linear Collider (CLIC) requires a beam orbit measurement system with high spatial (50 nm) and high temporal resolution (50 ns) to resolve the beam position within the 156 ns long bunch train, traveling on an energy-chirped, minimum dispersive trajectory. A 15 GHz prototype cavity BPM has been commissioned in the probe beam-line of the CTF3 CLIC Test Facility. We discuss performance and technical details of this prototype installation, including the 15 GHz analogue downconverter, the data acquisition and the control electronics and software. An R&D outlook is given for the next steps, which requires a system of 3 cavity BPMs to investigate the full resolution potential.

  12. Production of excited electrons at TESLA and CLIC based egamma colliders

    CERN Document Server

    Kirca, Z; Cakir, O

    2003-01-01

    We analyze the potential of TESLA and CLIC based electron-photon colliders to search for excited spin-1/2 electrons. The production of excited electrons in the resonance channel through the electron- photon collision and their subsequent decays to leptons and electroweak gauge bosons are investigated. We study in detail the three signal channels of excited electrons and the corresponding backgrounds through the reactions egamma yields egamma, egamma yields eZ and egamma yields vW. Excited electrons with masses up to about 90% of the available collider energy can be probed down to the coupling f = f prime = 0.05(0.1) at TESLA(CLIC) based egamma colliders. 22 Refs.

  13. Correction of beam-beam effects in luminosity measurement in the forward region at CLIC

    CERN Document Server

    Lukic, Strahinja

    2013-01-01

    Procedures for correcting the beam-beam effects in luminosity measurement at CLIC at 3 TeV CM energy are described and tested using Monte Carlo simulations: -> Correction of the angular counting loss due to the combined Beamstrahlung and initial-state radiation (ISR) effects, based on the reconstructed velocity of the collision frame of the Bhabha scattering. -> Deconvolution of the luminosity spectrum distortion due to the ISR emission. -> Correction of the counting bias due to the finite calorimeter energy resolution. All procedures were tested by simulation. Bhabha events were generated using BHLUMI, and used in Guinea-PIG to simulate the outgoing momenta of Bhabha particles in the bunch collisions at CLIC. Residual uncertainties after correction are listed in a table in the conclusions. The beam-beam related systematic counting uncertainty in the luminosity peak can be reduced to the order of permille.

  14. Correction of beam-beam effects in luminosity measurement in the forward region at CLIC

    CERN Document Server

    Lukic, Strahinja

    2013-01-01

    Procedures for correcting the beam-beam effects in luminosity measurement at CLIC at 3 TeV CM energy are described and tested using Monte Carlo simulations: - Correction of the angular counting loss due to the combined Beamstrahlung and initial-state radiation (ISR) effects, based on the reconstructed velocity of the collision frame of the Bhabha scattering. - Deconvolution of the luminosity spectrum distortion due to the ISR emission. - Correction of the counting bias due to the finite calorimeter energy resolution. All procedures were tested by simulation. Bhabha events were generated using BHLUMI, and used in Guinea-PIG to simulate the outgoing momenta of Bhabha particles in the bunch collisions at CLIC. Residual uncertainties after correction are listed in a table in the conclusions. The beam-beam related systematic counting uncertainty in the luminosity peak can be reduced to the order of permille.

  15. On-Line Dispersion Free Steering for the Main Linac of CLIC

    CERN Document Server

    Pfingstner, J

    2013-01-01

    For future linear colliders as well as for light sources, ground motion effects are a severe problem for the accelerator performance. After a few minutes, orbit feedback systems are not sufficient to mitigate all ground motion effects and additional long term methods will have to be deployed. In this paper, the long term ground motion effects in the main linac of the Compact Linear Collider (CLIC) are analysed via simulation studies. The primary growth of the projected emittance is identified to originate from chromatic dilutions due to dispersive beam orbits. To counter this effect, an on-line identification algorithm is applied to measure the dispersion parasitically. This dispersion estimate is used to correct the beam orbit with an iterative dispersion free steering algorithm. The presented results are not only of interest for the CLIC project, but for all linacs in which the dispersive orbit has to be corrected over time.

  16. Thermo-mechanical Analysis of the CLIC Post-Linac Energy Collimators

    CERN Document Server

    Resta-Lopez, J; Latina, A

    2012-01-01

    The post-linac energy collimation system of the Compact Linear Collider (CLIC) has been designed for passive protection of the Beam Delivery System (BDS) against miss-steered beams due to failure modes in the main linac. In this paper, a thermo-mechanical analysis of the CLIC energy collimators is presented. This study is based on simulations using the codes FLUKA and ANSYS when an entire bunch train hits the collimators. Different failure mode scenarios in the main linac are considered. The aim is to improve the collimator in order to make a reliable and robust design so that survives without damage the impact of a full bunch train in case of likely events generating energy errors.

  17. Design of the Injection and extraction system and related machine protection for the Clic Damping Rings

    CERN Document Server

    Apsimon, Robert; Barnes, Mike; Borburgh, Jan; Goddard, Brennan; Papaphilippou, Yannis; Uythoven, Jan

    2014-01-01

    Linear machines such as CLIC have relatively low rates of collision between bunches compared to their circular counterparts. In order to achieve the required luminosity, a very small spot size is envisaged at the interaction point, thus a low emittance beam is needed. Damping rings are essential for producing the low emittances needed for the CLIC main beam. It is crucial that the beams are injected and extracted from the damping rings in a stable and repeatable fashion to minimise emittance blow-up and beam jitter at the interaction point; both of these effects will deteriorate the luminosity at the interaction point. In this paper, the parameters and constraints of the injection and extraction systems are considered and the design of these systems is optimised within this parameter space. Related machine protection is considered in order to prevent damage from potential failure modes of the injection and extraction systems.

  18. Power pulsing scheme for analog and digital electronics of the vertex detectors at CLIC

    CERN Document Server

    Blanchot, Georges

    2015-01-01

    The precision requirements of the vertex detector at CLIC impose strong limitations on the mass of such a detector (< 0.2% of a radiation length, Xo, per layer). To achieve such a low material budget, ultra-thin hybrid pixel detectors are foreseen, while the mass for cooling and services will be reduced by implementing a power pulsing scheme that takes advantage of the low duty cycle of the accelerator. The principal aim is to achieve significant power reduction without compromising the power integrity supplied to the front-end electronics. This report summarises the study of a power pulsing scheme to power the vertex barrel electronics of the future CLIC experiment. Its main goal is to describe in more detail what has been already presented in TWEPP conferences and other presentations. The report can therefore serve as an operator manual for future use and development of the system

  19. Laser Wire Scanner Basic Process and Perspectives for the CTF's and CLIC Machines

    CERN Document Server

    Lefèvre, T

    2002-01-01

    In a laser wire scanner, the basic idea is to replace the solid wire classically used in a standard wire scanner by a narrow laser beam. The basic process involved is the Thomson-Compton scattering process, where photons are scattered from the laser beam by the incoming electrons. By counting the number of scattered photons or degraded electrons as a function of laser position the bunch profile can be reconstructed. In this note the Compton scattering mechanism is first presented. In the framework of the CLIC project, a laser wire scanner (LWS) could be used as a non-interfering beam profile measurement both on the Drive Beam for a high current electron beam and on the Main Beam for very small electron beam sizes. A design for a LWS on the CTF2 and CTF3 machines is proposed and some considerations for the use of a LWS on the CLIC main beam are also mentioned.

  20. Status of a study of stabilization and fine positioning of CLIC quadrupoles to the nanometre level

    CERN Document Server

    Artoos, K; Esposito, M; Fernandez Carmona, P; Guinchard, M; Hauviller, C; Janssens, S; Kuzmin, A; Leuxe, R; Moron Ballester, R

    2011-01-01

    Mechanical stability to the nanometre and below is required for the Compact Linear Collider (CLIC) quadrupoles to frequencies as low as 1 Hz. An active stabilization and positioning system based on very stiff piezo electric actuators and inertial reference masses is under study for the Main Beam Quadrupoles (MBQ). The stiff support was selected for robustness against direct forces and for the option of incrementally repositioning the magnet with nanometre resolution. The technical feasibility was demonstrated by a representative test mass being stabilized and repositioned to the required level in the vertical and lateral direction. Technical issues were identified and the development programme of the support, sensors, and controller was continued to increase the performance, integrate the system in the overall controller, adapt to the accelerator environment, and reduce costs. The improvements are implemented in models, test benches, and design of the first stabilized prototype CLIC magnet. The characterizati...

  1. Structural evolution during mechanical deformation in high-barrier PVDF-TFE/PET multilayer films using in situ X-ray techniques.

    Science.gov (United States)

    Jordan, Alex M; Lenart, William R; Carr, Joel M; Baer, Eric; Korley, Lashanda T J

    2014-03-26

    Poly(vinylidene fluoride-co-tetrafluoroethylene) (PVDF-TFE) is confined between alternating layers of poly(ethylene terephthalate) (PET) utilizing a unique multilayer processing technology, in which PVDF-TFE and PET are melt-processed in a continuous fashion. Postprocessing techniques including biaxial orientation and melt recrystallization were used to tune the crystal orientation of the PVDF-TFE layers, as well as achieve crystallinity in the PET layers through strain-induced crystallization and thermal annealing during the melt recrystallization step. A volume additive model was used to extract the effect of crystal orientation within the PVDF-TFE layers and revealed a significant enhancement in the modulus from 730 MPa in the as-extruded state (isotropic) to 840 MPa in the biaxially oriented state (on-edge) to 2230 MPa in the melt-recrystallized state (in-plane). Subsequently, in situ wide-angle X-ray scattering was used to observe the crystal structure evolution during uniaxial deformation in both the as-extruded and melt-recrystallized states. It is observed that the low-temperature ferroelectric PVDF-TFE crystal phase in the as-extruded state exhibits equatorial sharpening of the 110 and 200 crystal peaks during deformation, quantified using the Hermans orientation function, while in the melt-recrystallized state, an overall increase in the crystallinity occurs during deformation. Thus, we correlated the mechanical response (strain hardening) of the films to these respective evolved crystal structures and highlighted the ability to tailor mechanical response. With a better understanding of the structural evolution during deformation, it is possible to more fully characterize the structural response to handling during use of the high-barrier PVDF-TFE/PET multilayer films as commercial dielectrics and packaging materials. PMID:24593226

  2. Implications of a Curved Tunnel for the Main Linac of CLIC

    CERN Document Server

    Latina, Andrea; Schulte, Daniel

    2006-01-01

    Preliminary studies of a linac that follows the earth curvature are presented for the CLIC main linac. The curvature of the tunnel is modeled in a realistic way by use of geometry changing elements. The emittance preservation is studied for a perfect machine as well as taking into account imperfections. Results for a curved linac are compared with those for a laser-straight machine.

  3. Study of a 5-Tesla large aperture coil for the CLIC detector

    CERN Document Server

    Cure, B

    2011-01-01

    The present design of a CLIC detector foresees a large solenoid magnet with a 6 m aperture and a magnetic induction of 5 T at the interaction point. This can be achieved by a thin superconducting coil. This report gives the typical main parameters of such a coil and presents the feasibility based on and compared with the CMS and Atlas solenoid coil designs, indicating the limits on the conductor and the identified R&D prospects.

  4. Analyzing the Anomalous Dipole Moment Type Couplings of Heavy Quarks with FCNC Interactions at the CLIC

    International Nuclear Information System (INIS)

    We examine both anomalous magnetic and dipole moment type couplings of a heavy quark via its single production with subsequent dominant standard model decay modes at the compact linear collider (CLIC). The signal and background cross sections are analyzed for heavy quark masses 600 and 700 GeV. We make the analysis to delimitate these couplings as well as to find the attainable integrated luminosities for 3σ observation limit

  5. Parameter scan for the CLIC Damping rings under the infleunce of intrabeam scattering

    CERN Document Server

    Antoniou, F; Papaphilippou, Y; Vivoli, A

    2010-01-01

    Due to the high bunch density, the output emittances of the CLIC Damping Rings (DR) are strongly dominated by the effect of Intrabeam Scattering (IBS). In an attempt to optimize the ring design, the bench-marking of the multiparticle tracking code SIRE with the classical IBS formalisms and approximations is first considered. The scaling of the steady state emittances and IBS growth rates is also studied, with respect to several ring parameters including energy, bunch charge and wiggler characteristics.

  6. Gluino Pair Production in $e^+ e^-$ and Photon-Photon Collisions at CERN CLIC

    CERN Document Server

    Berge, S; 10.1140/epjc/s2003-01194-4

    2003-01-01

    We confront the generally small cross sections for gluino pair production in e^+e^- annihilation with the much larger ones in photon-photon scattering at a multi-TeV linear collider like CERN CLIC. The larger rates and the steeper rise of the cross section at threshold may allow for a precise gluino mass determination in high-energy photon-photon collisions for a wide range of squark masses and post-LEP SUSY benchmark points.

  7. Nonlinear Optimization of CLIC DRS New Design with Variable Bends and High Field Wigglers

    CERN Document Server

    Ghasem, H.; Alabau-Gonzalvo, J.; Papadopoulou, S.; Papaphilippou, Y.

    2016-01-01

    The new design of CLIC damping rings is based on longitudinal variable bends and high field superconducting wiggler magnets. It provides an ultra-low horizontal normalised emittance of 412 nm-rad at 2.86 GeV. In this paper, nonlinear beam dynamics of the new design of the damping ring (DR) with trapezium field profile bending magnets have been investigated in detail. Effects of the misalignment errors have been studied in the closed orbit and dynamic aperture.

  8. The Event Display for CLIC: DD4hep Compatibility and Improvements

    CERN Document Server

    Quast, Thorben

    2015-01-01

    This document is a short summary of my contributions to the Event Display for the CLICdp Software group in the context of CERN’s Summer Student Programme 2015. After a brief outline of CLIC and the relevant software package, the project is motivated. The individual achievements and their technical realizations are explained rather qualitatively, as details are well documented directly in the source code.

  9. High performance electronics for alignment regulation on the CLIC 30GHz modules

    International Nuclear Information System (INIS)

    CERN is studying a linear collider (CLIC) to obtain electron-positron collisions with centre-of-mass energies in the TeV range. To demonstrate the feasibility of CLIC, a test facility (CTF2) is being constructed. CTF2 consists of 4 identical modules, each 1.4 m long module consists of 2 linac with a girder and a doublet or a triplet quadrupole. Girders are elements that support mechanically the cavities of the accelerator while the main objective of the quadrupole is to focus particle beams. The alignment system has 2 principal utilities. The first is to pre-align the elements to make the beam pass through the aperture and produce signals in beam position monitors. In respect to these signals the girders and the quadrupoles are moved for making the definitive alignment. The second utility is to maintain the elements in this position. The alignment control system of CTF2 must regulate the position of the girders and quadrupoles with a precision < 10 μm. In fact an accuracy of 1 μ has been obtained on CTF2. Thanks to its flexibility and its simplicity, the system is expected to adapt easily to CLIC even if it means to control modules that involve up to a maximum of 384 motors and 896 sensors

  10. Evaluation of Components for the High Precision Inductive Adder for the CLIC Damping Rings

    CERN Document Server

    Holma, J

    2012-01-01

    The CLIC study is exploring the scheme for an electron-positron collider with high luminosity and a nominal centre-of-mass energy of 3 TeV. The CLIC damping rings will produce, through synchrotron radiation, ultra-low emittance beam with high bunch charge, necessary for the luminosity performance of the collider. To limit the beam emittance blow-up due to oscillations, the pulse generators for the damping ring kickers must provide extremely flat high-voltage pulses. The specifications for the extraction kickers of the CLIC damping rings are particularly demanding: the flattop of the output pulse must be 160 ns duration, 12.5 kV and 250 A, with a combined ripple and droop of not more than ±0.02 %. An inductive adder allows the use of different modulation techniques and is therefore a very promising approach to meeting the specifications. In addition to semiconductors working in their saturated region, semiconductors working in their linear region are needed for applying analogue modulation techniques. Simulat...

  11. En route vers la nano stabilisation de CLIC faisceau principale et focalisation finale

    CERN Document Server

    Artoos, K; Guinchard, M; Hauviller, Claude; Lackner, F; CERN. Geneva. TS Department

    2008-01-01

    Pour atteindre la luminosité voulue de CLIC, la taille transversale du faisceau doit être de l?ordre du nanomètre. Ceci nécessite une stabilité vibratoire des quadripôles du faisceau principal de 1 nm et même 0.1 nm pour les doublets de la focalisation finale. La nano technologie et la nano stabilisation sont des activités qui évoluent rapidement dans l?industrie et centres de recherche pour des applications très variées comme l?électronique, l?optique, la chimie voire la médecine. Cette présentation décrit les avancées techniques nécessaires pour atteindre l?objectif de CLIC et les projets et collaborations R&D prévus pour démontrer la faisabilité de la nano stabilisation de CLIC en 2010.

  12. Klystron Modulators for the 3 TeV CLIC Scheme An Overview

    CERN Document Server

    Pearce, P

    2001-01-01

    The CLIC (Compact Linear Collider) design is based on the Two-Beam technology being developed at CERN. The Drive Beam accelerator will have about 200 multi-beam klystron-modulator (MBK-M) RF power sources for each drive beam linac. These multi-beam klystrons (MBKs) should provide up to 50 MW peak power at 937 MHz, with a 100 ms pulse width and operating at 100 Hz repetition frequency. The CLIC drive beam injector will also use a number of these same MBK-Ms operating at slightly lower power levels. A 0.5 MW peak power, 468 MHz klystron with a bandwidth of around 150 MHz will be required for the sub-harmonic buncher in each drive beam injector chain as well. The Main Beams injector complex is required to deliver e+ and e- beams at 9 GeV via the transfer lines to the CLIC Main Beam accelerator. The present injector complex design uses a series of linacs to accelerate the electron and positron beams coming from RF guns working at 1.5 GHz up to an energy of 1.98 GeV before they are put into damping rings. Each of ...

  13. Study on Structure and Properties of PP/PET/EPDM-g-GMA Blend%PP/PET/EPDM-g-GMA共混物结构与性能研究

    Institute of Scientific and Technical Information of China (English)

    许军; 姚琲; 朱晨

    2007-01-01

    通过反应共混制备了PP/PET/EPDM-g-GMA共混物.用扫描电镜和图像处理软件对共混物形貌进行定性和定量分析,用偏光显微镜观察共混物等温结晶形态,最后测量共混物的力学性能.结果表明:在PP/PET共混物中加入EPDM-g-GMA后,两相相容性改善,进一步加入成核剂后分散相尺寸更小、粒径分布更均匀;PP球晶随PET的混入而减小;在PP/PET体系中加入EPDM-g-GMA起到反应增容和橡胶增韧的协同效应,使缺口冲击强度由未加增容剂时的2.0 kJ/m2提高至6.6 kJ/m2,弹性模量较PP提高了38%;PP/PET共混物的拉伸强度随PET含量的增加下降,在相同PET含量的情况下,加入EPDM-g-GMA后,共混物的拉伸强度与未增容体系基本一致.

  14. Measurement of the H$\\rightarrow$WW$^*$ Branching Ratio at 1.4TeV using the semileptonic final state at CLIC

    CERN Document Server

    AUTHOR|(SzGeCERN)762723; Watson, Nigel

    2016-01-01

    This note summarises a study to evaluate the potential to measure the H$\\rightarrow$WW$^*$ branching fraction at CLIC, 1.4TeV centre-of-mass energy, with the CLIC_ILD detector, using the WW$\\rightarrow$qql$\

  15. PET/CT - Current status

    International Nuclear Information System (INIS)

    From autoradiography to planar X rays, computed tomography (CT) and Magnetic Resonance (MR), morphology and structure has been the mainstay of biological and medical imaging for over a century. While structural changes may suggest the presence of disease, functional changes are more sensitive indicators of early-stage pathology, and with cancer, early detection is the key to a favorable prognosis. Since molecular imaging offers the potential to quantitatively image functional changes in vivo, it is assuming an increasingly important role in the identification, staging and re-staging of human disease. Specifically, Positron Emission Tomography (PET) and Single Photon Emission Computed Tomography (SPECT) are sensitive techniques to map human physiology non-invasively through the use of high-resolution imaging devices and appropriate radioactively-labeled biomarkers. However, such metabolic maps do not offer the structural detail associated with anatomical imaging techniques such as CT and MR and therefore dual modality devices such as PET/CT, SPECT/CT or PET/MR that combine both structural and functional information offer a more complete and accurate assessment of the status of disease. PET/CT instrumentation, for example, was first introduced into the clinic in 2001 and since then, progress has been rapid. Technological advances in each modality, CT and PET, have been consistently incorporated into the combined device ensuring state-of-the-art performance for PET/CT. Recent advances in CT include an increase in the number of detector rows or slices (from 1 to 64), a reduction in rotation times (to less than 0.5 s), and the emergence of the first CT scanner incorporating dual X ray sources. Paralleling these advances, PET instrumentation has witnessed the introduction of new faster scintillators, higher resolution detectors, increased sensitivity through extended axial coverage, and the resurgence of time-of-flight information to improve image signal-to-noise. A

  16. Clinical application of pet

    Directory of Open Access Journals (Sweden)

    Francisco Lomeña

    2005-10-01

    Full Text Available Positron emission tomography (PET is an imaging modality that gives information on tissue metabolism and functionalism, different from other imaging techniques like computed tomography (CT and magnetic resonance imaging (MRI, which provide anatomical or structural information. PET has reached its development in biomedical research because of its capacity to use analogous compounds of many endogenous substance as tracers, and to measure, in vivo and in a non-invasive way, their consumption by the different organs and tissues of the mammalian body. Fluordeoxyglucose-F18 (FDG PET has been proven to be a tracer adequate for clinical use in oncology and in many neurological diseases, with an excellent cost-efficiency ratio. The current PET-CT scanners can come to be the best tools for exploring patients who suffer from cancer.A tomografia por emissão de pósitrons (PET é uma técnica de diagnóstico por imagem que fornece informação sobre o metabolismo e funcionamento dos tecidos, diferente de outras técnicas de imagens como tomografia computadorizada (TC e ressonância magnética (RM, as quais fornecem informações estruturais ou anatômicas. O PET alcançou seu desenvolvimento em investigação biomédica devido à sua capacidade de usar traçadores análogos a muitas substâncias endógenas e de medir in vivo e de forma não invasiva seu consumo em diferentes órgãos e tecidos dos mamíferos 18Fluordesoxiglicose (FDG PET tem provado ser uma exploração de uso clínico com excelente relação custo benefício em oncologia e em muitas doenças neurológicas. Os atuais tomógrafos por PET-CT podem chegar a ser a melhor ferramenta de diagnóstico nos pacientes que sofrem de câncer.

  17. A study of structure formation on PET, PBT, and PS surfaces by excimer laser ablation

    Science.gov (United States)

    Kim, Jongdae

    Usually polymer surface treatment is performed to modify surface layers by inserting some functional group and/or by inducing roughness on surfaces to improve their wettability, printability, and adhesion to other polymers or metals. In this work, different polymer surfaces were treated using an excimer laser (LPX 240i, Lambda Physik). Polystyrene, polyethylene terephtalate, and polybutylene terephtalate were chosen as model materials for this study. Films were made by cast film processing and stretched with biaxial stretching machine. With excimer laser treatment on polymer surfaces, it was found that we could produce 1--2 micron size structures depending on material properties and film processing conditions. Materials with lower UV absorption coefficient produced double digit micron size structures, while those with higher UV absorption coefficients produced single digit micron size structures. In all these cases the structures formed only on stretched films. In addition to those microstructure developments, the determination of ablation threshold fluence was of interest mainly for understanding fundamentals of ablation behavior and technical applications. In this study, ablation thresholds were measured by various methods including ablation depth, ablation weight, and ablation sound level measurements. Among these methods, we confirmed that the measurement by ablation sound level gives the most reliable results, because this method is based on single pulse ablation. To understand the ablation phenomenon, and how microstructures can be developed during ablation, different material processing and excimer laser conditions were chosen for experimentation. During our experiments, we observed incubation phenomenon during laser ablation and showed that this incubation was significant for materials with low UV absorption coefficients. Based on UV absorption value change after excimer laser irradiation, we proposed a mechanism to explain the ablation of PS films. From

  18. Processing and characterization of extruded PET and its r-PET and MWCNT nanocomposite thin films by spin coating

    Indian Academy of Sciences (India)

    Arvind R Singh; Vineeta D Deshpande

    2016-02-01

    The objective of the present study was basic understanding of the formation of thin film morphology by spin coating using reorganized polyethylene terephthalate (r-PET) and multiwalled carbon nanotubes (MWCNTs) as fillers in PET. A study of the correlation between physical properties of the PET films and its surface morphology was carried out using atomic force microscopy-based power spectral density (PSD) analysis. No significant work of surface analysis, using PSD of thin films of PET has been reported till date. Dilute solution of PET, PET with 3 wt% (r-PET) and PET with 3 wt% (2 wt% r-PET + 1 wt% MWCNT) filler were prepared using trifluoroacetic acid (TFA) as a solvent and thin films were fabricated on glass substrate by the optimized spin coating technique. Preparation of r-PET and r-PET+ MWCNT fillers was obtained by the precipitation method using TFA as a solvent and acetone as an antisolvent. The samples before spin coating were extruded and for comparison, a film of non-extruded PET was also prepared. Structural studies by Fourier transform infrared and X-ray diffraction show higher degree of crystallinity in r-PET and decrease in chain entanglements. Owing to the crystallizing behaviour of r-PET, it allows better dispersion of MWCNT in the polymer matrix as compared with PET. The samples with fillers of MWCNT show more compact and unique mesh-like globular structure, indicating application for electromagnetic shielding foams and fibres.

  19. FLUIDS, PLASMAS AND ELECTRIC DISCHARGES: The influence of the structures and compounds of DLC coatings on the barrier properties of PET bottles

    Science.gov (United States)

    Yang, Li; Wang, Zhen-Duo; Zhang, Shou-Ye; Yang, Li-Zhen; Chen, Qiang

    2009-12-01

    To reduce the oxygen transmission rate through a polyethylene terephthalate (PET) bottle (an organic plastic) diamond-like carbon (DLC) coatings on the inner surface of the PET bottle were deposited by radio frequency plasma-enhanced chemical vapour deposition (RF-PECVD) technology with C2H2 as the source of carbon and Ar as the diluted gas. As the barrier layer to humidity and gas permeation, this paper analyses the DLC film structure, composition, morphology and barrier properties by Fourier transform infrared, atomic force microscopy, scanning electron microscopy and oxygen transmission rate in detail. From the spectrum, it is found that the DLC film mainly consists of sp3 bonds. The barrier property of the films is significantly relevant to the sp3 bond concentration in the coating, the film thickness and morphology. Additionally, it is found that DLC film deposited in an inductively coupled plasma enhanced capacitively coupled plasma source shows a compact, homogeneous and crack-free surface, which is beneficial for a good gas barrier property in PET bottles.

  20. Long span DNA paired-end-tag (DNA-PET sequencing strategy for the interrogation of genomic structural mutations and fusion-point-guided reconstruction of amplicons.

    Directory of Open Access Journals (Sweden)

    Fei Yao

    Full Text Available Structural variations (SVs contribute significantly to the variability of the human genome and extensive genomic rearrangements are a hallmark of cancer. While genomic DNA paired-end-tag (DNA-PET sequencing is an attractive approach to identify genomic SVs, the current application of PET sequencing with short insert size DNA can be insufficient for the comprehensive mapping of SVs in low complexity and repeat-rich genomic regions. We employed a recently developed procedure to generate PET sequencing data using large DNA inserts of 10-20 kb and compared their characteristics with short insert (1 kb libraries for their ability to identify SVs. Our results suggest that although short insert libraries bear an advantage in identifying small deletions, they do not provide significantly better breakpoint resolution. In contrast, large inserts are superior to short inserts in providing higher physical genome coverage for the same sequencing cost and achieve greater sensitivity, in practice, for the identification of several classes of SVs, such as copy number neutral and complex events. Furthermore, our results confirm that large insert libraries allow for the identification of SVs within repetitive sequences, which cannot be spanned by short inserts. This provides a key advantage in studying rearrangements in cancer, and we show how it can be used in a fusion-point-guided-concatenation algorithm to study focally amplified regions in cancer.

  1. Long Span DNA Paired-End-Tag (DNA-PET) Sequencing Strategy for the Interrogation of Genomic Structural Mutations and Fusion-Point-Guided Reconstruction of Amplicons

    Science.gov (United States)

    Hillmer, Axel M.; Lee, Wah Heng; Li, Guoliang; Teo, Audrey S. M.; Woo, Xing Yi; Zhang, Zhenshui; Chen, Jieqi P.; Poh, Wan Ting; Zawack, Kelson F. B.; Chan, Chee Seng; Leong, See Ting; Neo, Say Chuan; Choi, Poh Sum D.; Gao, Song; Nagarajan, Niranjan; Thoreau, Hervé; Shahab, Atif; Ruan, Xiaoan; Cacheux-Rataboul, Valère; Wei, Chia-Lin; Bourque, Guillaume; Sung, Wing-Kin; Liu, Edison T.; Ruan, Yijun

    2012-01-01

    Structural variations (SVs) contribute significantly to the variability of the human genome and extensive genomic rearrangements are a hallmark of cancer. While genomic DNA paired-end-tag (DNA-PET) sequencing is an attractive approach to identify genomic SVs, the current application of PET sequencing with short insert size DNA can be insufficient for the comprehensive mapping of SVs in low complexity and repeat-rich genomic regions. We employed a recently developed procedure to generate PET sequencing data using large DNA inserts of 10–20 kb and compared their characteristics with short insert (1 kb) libraries for their ability to identify SVs. Our results suggest that although short insert libraries bear an advantage in identifying small deletions, they do not provide significantly better breakpoint resolution. In contrast, large inserts are superior to short inserts in providing higher physical genome coverage for the same sequencing cost and achieve greater sensitivity, in practice, for the identification of several classes of SVs, such as copy number neutral and complex events. Furthermore, our results confirm that large insert libraries allow for the identification of SVs within repetitive sequences, which cannot be spanned by short inserts. This provides a key advantage in studying rearrangements in cancer, and we show how it can be used in a fusion-point-guided-concatenation algorithm to study focally amplified regions in cancer. PMID:23029419

  2. Pet Allergy Quiz

    Science.gov (United States)

    ... people with pet allergy do better with a dog that has short hair or sheds less. Question 2 Pet allergies are triggered by the hair on a pet. True False False: Pet allergies are caused by an allergen found on the pet’s skin (dander), saliva or urine. Question 3 Symptoms of pet allergy ...

  3. Structure and stability of hexadentate complexes of ligands based on AAZTA for efficient PET labelling with gallium-68.

    Science.gov (United States)

    Waldron, Bradley P; Parker, David; Burchardt, Carsten; Yufit, Dmitry S; Zimny, Melanie; Roesch, Frank

    2013-01-21

    Pre-organised tricarboxylate ligands based on 6-amino-perhydro-1,4-diazepine bind (68)Ga rapidly and selectively in acetate buffer at pH 4 to 7, forming kinetically stable complexes suitable for use in PET imaging. PMID:23212712

  4. Breast PET scan

    Science.gov (United States)

    Breast positron emission tomography; PET - breast; PET - tumor imaging - breast ... A PET scan requires a small amount of radioactive material (tracer). This tracer is given through a vein (IV), usually ...

  5. Pet Care: MRSA FAQ

    Science.gov (United States)

    ... AVMA Meeting Dates Meetings & CE Calendar Symposiums & Summits Pet Health Awareness Events About AVMA Who We Are ... 12 Educators You are here: Home | Public Resources | Pet Care Print Share This! Your Veterinarian Pet Care ...

  6. Current status and future perspective of PET

    International Nuclear Information System (INIS)

    Positron Emission Tomography (PET) is a nuclear medicine imaging modality that consists of systemic administration to a subject of a radiopharmaceutical labeled with a positron-emitting radionuclide. Following administration, its distribution in the organ or structure under study can be assessed as a function of time and space by (1) detecting the annihilation radiation resulting from the interaction of the positrons with matter, and (2) reconstructing the distribution of the radioactivity from a series of that used in computed tomography (CT). The nuclides most generally exhibit chemical properties that render them particularly desirable in physiological studies. The radionuclides most widely used in PET are F-18, C-11, O-15 and N-13. Regarding to the number of the current PET Centers worldwide (based on ICP data), more than 300 PET Centers were in operation in 2000. The use of PET technology grew rapidly compared to that in 1992 and 1996, particularly in the USA, which demonstrates a three-fold rise in PET installations. In 2001, 194 PET Centers were operating in the USA. In 1994, two clinical and research-oriented PET Centers at Seoul National University Hospital and Samsung Medical Center, was established as the first dedicated PET and Cyclotron machines in Korea, followed by two more PET facilities at the Korea Cancer Center Hospital, Ajou Medical Center, Yonsei University Medical Center, National Cancer Center and established their PET Center. Catholic Medical School and Pusan National University Hospital have finalized a plan to install PET machine in 2002, which results in total of nine PET Centers in Korea. Considering annual trends of PET application in four major PET centers in Korea in Asan Medical Center recent six years (from 1995 to 2000), a total of 11,564 patients have been studied every year and the number of PET studies has shown steep growth year upon year. We had, 1,020 PET patients in 1995. This number increased to 1,196, 1,756, 2,379, 3

  7. PET/CT and PET - application in pediatric oncology; PET/CT und PET - Einsatz in der paediatrischen Onkologie

    Energy Technology Data Exchange (ETDEWEB)

    Franzius, C.; Lang, K.; Schober, O. [Klinik und Poliklinik fuer Nuklearmedizin, Univ. Muenster (Germany); Wormanns, D. [Inst. fuer klinische Radiologie, Univ. Muenster (Germany); Vormoor, J. [Klinik und Poliklinik fuer Kinder- und Jugendmedizin - Paediatrische Haematologie und Onkologie, Univ. Muenster (Germany)

    2004-12-01

    PET-CT is a new imaging technology with a high capability to improve oncologic imaging. Introduction into clinical practise started approximately 3 years ago. Consequently, the available literature data are preliminary. There are no studies concerning PET-CT in pediatric patients. Nevertheless, it can already be supposed that the synthesis of structural and metabolic information improves the accuracy of staging and has the realistic potential to change patient management in a relevant percentage rate in pediatric patients. In this article, the advantages and special features of the application of PET-CT in young oncologic patients are pointed out. Potential clinical applications of PET-CT in this patient group include Hodgkin and non-Hodgkin lymphomas, Ewing tumors, osteosarcomas, rhabdomyosarcomas and neuroblastomas. (orig.)

  8. American Pet Culture

    Institute of Scientific and Technical Information of China (English)

    海焰

    2007-01-01

    In America you can find dogs,cats, horses,monkeys, snakes and even pigs in almost every family.They are their pets.Americans love pets and look on them as a part of the family.Sometimes pet owners dress their pets in fashionable clothes.They even buy toys for their pets.Americans love their pets as their children, sometimes even better.

  9. Progressive hearing loss and vestibular dysfunction caused by a homozygous nonsense mutation in CLIC5

    OpenAIRE

    Seco, Celia Zazo; Oonk, Anne MM; Domínguez-Ruiz, María; Draaisma, Jos MT; Gandía, Marta; Oostrik, Jaap; Neveling, Kornelia; Kunst, Henricus PM; Hoefsloot, Lies H.; del Castillo, Ignacio; Pennings, Ronald JE; Kremer, Hannie; Admiraal, Ronald JC; Schraders, Margit

    2014-01-01

    In a consanguineous Turkish family diagnosed with autosomal recessive nonsyndromic hearing impairment (arNSHI), a homozygous region of 47.4 Mb was shared by the two affected siblings on chromosome 6p21.1-q15. This region contains 247 genes including the known deafness gene MYO6. No pathogenic variants were found in MYO6, neither with sequence analysis of the coding region and splice sites nor with mRNA analysis. Subsequent candidate gene evaluation revealed CLIC5 as an excellent candidate gen...

  10. Production of excited electrons at TESLA and CLIC based $e\\gamma$ colliders

    CERN Document Server

    Aydin, Z Z; Kirca, Z

    2003-01-01

    We analyze the potential of TESLA and CLIC based electron-photon colliders to search for excited spin-1/2 electrons. The production of excited electrons in the resonance channel through the electron-photon collision and their subsequent decays to leptons and electroweak gauge bosons are investigated. We study in detail the three signal channels of excited electrons and the corresponding backgrounds through the reactions e gamma --> e gamma, e gamma --> eZ and e gamma --> nu W. Excited electrons can be discovered with the masses up to about 90% of the available collider energy.

  11. A Search for Leptophilic Vector Boson Z_l at CLIC by Using Neural Networks

    CERN Document Server

    Akkoyun, S

    2012-01-01

    In this work, the possible dynamics associated with leptophilic Z_l boson at CLIC (Compact Linear Collider) have been investigated by using artificial neural networks (ANNs). These hypotetic massive boson Z_l have been shown through the process e+e- -> M+M-. Furthermore, the invariant mass distributions for final muons have been consistently predicted by using ANN. For these highly non-linear data, we have constructed consistent empirical physical formulas (EPFs) by appropriate feed- forward ANN. These ANN-EPFs can be used to derive further physical functions which could be relevant to studying Z_l.

  12. Anomalous production of top quarks at CLIC+LHC based gamma p colliders

    CERN Document Server

    Cakir, O

    2003-01-01

    The single production of top quark due to flavor changing neutral current (FCNC) interaction and its decay to bW are studied at CLIC+LHC based gamma-p colliders. We consider both t-c-gamma and t-u-gamma anomalous couplings. The anomalous charm (up) quark anomalous coupling parameter kappa_gamma^c (kappa_gamma^u) can be probed down to 9.5x10^-3 (8.0x10^-3) at a gamma-p collider with sqrt{s_ep}=6.48 TeV and L_int=100 fb^-1.

  13. Feed Forward Orbit Correction in the CLIC Ring to Main LINAC Transfer lines

    CERN Document Server

    Apsimon, R; Schulte, D; Uythoven, J

    2014-01-01

    The emittance growth in the betatron collimation system of the 27 km long transfer lines between the CLIC damping rings and the main LINAC depends strongly on the transverse orbit jitter. The resulting stability requirements of the damping ring extraction elements seem extremely difficult to achieve. Position and angle feed forward systems in these long transfer lines bring the specified parameters of the extraction elements within reach. The designs of the optics and feed forward hardware are presented together with tracking simulations of the systems.

  14. Fluka and thermo-mechanical studies for the CLIC main dump

    CERN Document Server

    Mereghetti, Alessio; Vlachoudis, Vasilis

    2011-01-01

    In order to best cope with the challenge of absorbing the multi-MW beam, a water beam dump at the end of the CLIC post-collision line has been proposed. The design of the dump for the Conceptual Design Report (CDR) was checked against with a set of FLUKA Monte Carlo simulations, for the estimation of the peak and total power absorbed by the water and the vessel. Fluence spectra of escaping particles and activation rates of radio-nuclides were computed as well. Finally, the thermal transient behavior of the water bath and a thermo-mechanical analysis of the preliminary design of the window were done.

  15. Evaluation of 65nm technology for CLIC pixel front-end

    CERN Document Server

    Valerio, P; Ballabriga, R; Campbell, M; Llopart, X

    2011-01-01

    The CLIC vertex detector design requires a high single point resolution (~ 3 μm) and a precise time stamp (≤ 10 ns). In order to achieve this spatial resolution, small pixels (in the order of 20 μm pitch) must be used, together with the measurement of the charge deposition of neighbouring channels. Designing such small pixels requires the use of a deep downscaled CMOS technology. This note describes the design and characterisation of suitable building blocks implemented in a commercial 65 nm process. The characterisation included an evaluation of the radiation hardness of the blocks.

  16. Z′ Resonance and Associated Zh Production at Future Higgs Boson Factory: ILC and CLIC

    OpenAIRE

    A. Gutiérrez-Rodríguez; Hernández-Ruíz, M. A.

    2015-01-01

    We study the prospects of the B-L model with an additional $Z'$ boson to be a Higgs boson factory at high-energy and high-luminosity linear electron positron colliders, such as the ILC and CLIC, through the Higgs-strahlung process $e^{+}e^{-}\\rightarrow (Z, Z') \\to Zh$, including both the resonant and non-resonant effects. We evaluate the total cross section of $Zh$ and we calculate the total number of events for integrated luminosities of 500-2000\\hspace{0.8mm}$fb^{-1}$ and center of mass en...

  17. Simulation of Phase Stability at the Flat Top of the CLIC Drive Beam

    CERN Document Server

    Gerbershagen, A; Burrows, P

    2011-01-01

    The drive beam phase stability is one of the critical issues of the Compact Linear Collider (CLIC). In this paper the generation and propagation of drive beam phase errors is studied for effects that vary during the drive beam pulse. This includes the influence of drive beam current and phase errors as well as of drive beam accelerator RF phase and amplitude errors on the drive beam phase after the compressor chicanes and the analysis of the propagation of these errors through the drive beam combination scheme. The impact of the imperfections on the main beam is studied including the possible correction with help of a feedforward system.

  18. Pet Problems at Home: Pet Problems in the Community.

    Science.gov (United States)

    Soltow, Willow

    1984-01-01

    Discusses problems of pets in the community, examining the community's role related to disruptive pets and pet overpopulation. Also discusses pet problems at home, offering advice on selecting a pet, meeting a pet's needs, and disciplining pets. Includes a list of books, films/filmstrips, teaching materials, and various instructional strategies.…

  19. A Study on Pet Owners' Intention to Purchase Pet Insurance

    OpenAIRE

    Chiehwei Hung; Yen-Shan Chuang

    2014-01-01

    This study investigates the impacts of consumers¡¦ characteristics, pet feeding habits, pet spending and insurance conditions of pet owners on the intention to purchase a pet insurance policy. Our results reveal that family income, average monthly spending on pets, and experience of purchasing medical insurance are the significant determinants of a pet owner¡¦s intention to purchase pet insurance. Pet owners who have higher family income, higher pet spending, and who have previously purchased...

  20. Fast Beam-ion Instabilities in CLIC Main Linac Vacuum Specifications

    CERN Document Server

    Oeftiger, Adrian

    2011-01-01

    Specifications for the vacuum pressure in the CLIC electron Main Linac are determined by the onset of the fast beam-ion instability (FBII). When the electron beam is accelerated in the Main Linac, it ionizes the residual gas in the chamber through scattering ionization. If the density of ions around the beam exceeds a certain threshold, a resonant motion between the electron beam and the ions can be excited. A two-stream instability appears and as a result the beam acquires a coherent motion, which can quickly lead to beam quality degradation or even complete loss. Thus, the vacuum pressure must be kept below this threshold to prevent the excitation of FBII. The CLIC Main Linac poses an additional challenge with respect to previous FBII situations, because the gas ionization does not solely occur via scattering. The submicrometric beam sizes lead to extremely high electric fields around the beam and therefore result in field ionization beyond a certain threshold. The residual gas in the corresponding volume a...

  1. Initial measurements on a prototype inductive adder for the CLIC kicker systems

    CERN Document Server

    Holma, Janne

    2013-01-01

    The CLIC study is exploring the scheme for an electron-positron collider with high luminosity and a nominal centre-of-mass energy of 3 TeV. The CLIC pre-damping rings and damping rings will produce, through synchrotron radiation, ultra-low emittance beam with high bunch charge. To avoid beam emittance increase, the damping ring kicker systems must provide extremely flat, high-voltage, pulses. The specifications for the extraction kickers of the DRs are particularly demanding: the flattops of the pulses must be ±12.5 kV with a combined ripple and droop of not more than ±0.02 % (±2.5 V). An inductive adder is a very promising approach to meeting the specifications. To achieve ultra-flat pulses with a fast rise time the output impedance of the inductive adder needs to be well matched to the system impedance. The parasitic circuit elements of the inductive adder have a significant effect upon the output impedance and these values are very difficult to calculate accurately analytically. To predict these paramet...

  2. Modelling of Parasitic Inductances of a High Precision Inductive Adder for CLIC

    CERN Document Server

    Holma, J; Ovaska, S J

    2013-01-01

    The CLIC study is exploring the scheme for an electron-positron collider with high luminosity and a nominal centre-of-mass energy of 3 TeV. The CLIC pre-damping rings and damping rings will produce, through synchrotron radiation, ultra-low emittance beam with high bunch charge. To avoid beam emittance increase, the damping ring kicker systems must provide extremely flat, high-voltage, pulses. The specifications for the extraction kickers of the DRs are particularly demanding: the flat-top of the pulses must be ±12.5 kV with a combined ripple and droop of not more than ±0.02 % (±2.5 V). An inductive adder is a very promising approach to meeting the specifications. However, the output impedance of the inductive adder needs to be well matched to the system impedance. The primary leakage inductance, which cannot be computed accurately analytically, has a significant effect upon the output impedance of the inductive adder. This paper presents predictions, obtained by modelling the 3D geometry of the adder struc...

  3. Stabilisation and precision pointing quadrupole magnets in the Compact Linear Collider (CLIC)

    CERN Document Server

    Janssens, Stef; van den Brand, Jo; Bertolini, Alessandro; Artoos, Kurt

    This thesis describes the research done to provide stabilisation and precision positioning for the main beam quadrupole magnets of the Compact Linear Collider CLIC. The introduction describes why new particle accelerators are needed to further the knowledge of our universe and why they are linear. A proposed future accelerator is the Compact Linear Collider (CLIC) which consists of a novel two beam accelerator concept. Due to its linearity and subsequent single pass at the interaction point, this new accelerator requires a very small beam size at the interaction point, in order to increase collision effectiveness. One of the technological challenges, to obtain these small beam sizes at the interaction point, is to keep the quadrupole magnets aligned and stable to 1.5 nm integrated r.m.s. in vertical and 5 nm integrated root mean square (r.m.s.) in lateral direction. Additionally there is a proposal to create an intentional offset (max. 50 nm every 20 ms with a precision of +/- 1 nm), for several quadrupole ma...

  4. Integration of the PHIN RF Gun into the CLIC Test Facility

    CERN Document Server

    Döbert, Steffen

    2006-01-01

    CERN is a collaborator within the European PHIN project, a joint research activity for Photo injectors within the CARE program. A deliverable of this project is an rf Gun equipped with high quantum efficiency Cs2Te cathodes and a laser to produce the nominal beam for the CLIC Test Facility (CTF3). The nominal beam for CTF3 has an average current of 3.5 A, 1.5 GHz bunch repetition frequency and a pulse length of 1.5 ìs (2332 bunches) with quite tight stability requirements. In addition a phase shift of 180 deg is needed after each train of 140 ns for the special CLIC combination scheme. This rf Gun will be tested at CERN in fall 2006 and shall be integrated as a new injector into the CTF3 linac, replacing the existing injector consisting of a thermionic gun and a subharmonic bunching system. The paper studies the optimal integration into the machine trying to optimize transverse and longitudinal phase space of the beam while respecting the numerous constraints of the existing accelerator. The presented scheme...

  5. A CLIC Damping Wiggler Prototype at ANKA: Commissioning and Preparations for a Beam Dynamics Experimental Program

    CERN Document Server

    Bernhard, Axel; Casalbuoni, Sara; Ferracin, Paolo; Garcia Fajardo, Laura; Gerstl, Stefan; Gethmann, Julian; Grau, Andreas; Huttel, Erhard; Khrushchev, Sergey; Mezentsev, Nikolai; Müller, Anke-Susanne; Papaphilippou, Yannis; Saez de Jauregui, David; Schmickler, Hermann; Schoerling, Daniel; Shkaruba, Vitaliy; Smale, Nigel; Tsukanov, Valery; Zisopoulos, Panagiotis; Zolotarev, Konstantin

    2016-01-01

    In a collaboration between CERN, BINP and KIT a prototype of a superconducting damping wiggler for the CLIC damping rings has been installed at the ANKA synchrotron light source. On the one hand, the foreseen experimental program aims at validating the technical design of the wiggler, particularly the conduction cooling concept applied in its cryostat design, in a long-term study. On the other hand, the wiggler's influence on the beam dynamics particularly in the presence of collective effects is planned to be investigated. ANKA's low-alpha short-bunch operation mode will serve as a model system for these studies on collective effects. To simulate these effects and to make verifiable predictions an accurate model of the ANKA storage ring in low-alpha mode, including the insertion devices is under parallel development. This contribution reports on the first operational experience with the CLIC damping wiggler prototype in the ANKA storage ring and steps towards the planned advanced experimental program with th...

  6. Measurements on Prototype Inductive Adders with Ultra-Flat-Top Output Pulses for CLIC DR Kickers

    CERN Document Server

    Holma, J; Belver-Aguilar, C

    2014-01-01

    The CLIC study is investigating the technical feasibility of an electron-positron collider with high luminosity and a nominal centre-of-mass energy of 3 TeV. The CLIC pre-damping rings and damping rings (DRs) will produce ultra-low emittance beam with high bunch charge. To avoid beam emittance increase, the DR kicker systems must provide extremely flat, high-voltage, pulses. The specifications for the DR extraction kickers call for a 160 ns duration flat-top pulses of ±12.5 kV, 250 A, with a combined ripple and droop of not more than ±0.02 % (±2.5 V). An inductive adder is a very promising approach to meeting the specifications because this topology allows the use of both passive and analogue modulation methods to adjust the output waveform. Recently, two five-layer, 3.5 kV, prototype inductive adders have been built at CERN. The first of these has been used to test the passive and active analogue modulation methods to compensate voltage droop and ripple of the output pulses. Pulse waveforms have been reco...

  7. Prospects for the measurement of the Higgs Yukawa couplings to b and c quarks, and muons at CLIC

    Czech Academy of Sciences Publication Activity Database

    Grefe, C.; Laštovička, Tomáš; Strube, J.

    2013-01-01

    Roč. 73, č. 2 (2013), s. 1-7. ISSN 1434-6044 Institutional support: RVO:68378271 Keywords : Higgs * branching * ratio * Yukawa * couplings * quarks * muons * CLIC * inear collider Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 5.436, year: 2013

  8. Quantitative Techniques in PET-CT Imaging

    NARCIS (Netherlands)

    Basu, Sandip; Zaidi, Habib; Holm, Soren; Alavi, Abass

    2011-01-01

    The appearance of hybrid PET/CT scanners has made quantitative whole body scanning of radioactive tracers feasible. This paper deals with the novel concepts for assessing global organ function and disease activity based on combined functional (PET) and structural (CT or MR) imaging techniques, their

  9. PET AND PET-CT: PHYSICAL PRINCIPLE AND MEDICAL APLICATIONS

    Directory of Open Access Journals (Sweden)

    V.Rusu

    2007-04-01

    Full Text Available Positron emission tomography (PET is a noninvasive imaging method that can “see” the metabolisms inside the living cells. It involves the acquisition of functional images based on the detection of radiation coming from the positron emission of a radiotracer administered to the patient. This radiotracer can be a metabolic analog, like is the case of glucose analog 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (18FDG, the most commonly used PET radiotracer. PET images of the human body are used to evaluate a variety of diseases, most often to detect cancer and to examine the effects of cancer therapy by characterizing cell viability and biochemical changes in the cell. It is potentially useful in cancer imaging because the increased metabolism of tumor cells leads to increased uptake of glucose, and, therefore, uptake of 18FDG, also. PET-CT is the fusion of functional and anatomic information acquired almost simultaneously, that lets us see both the structural anatomy and the functional data on the same image. They complete each other: if PET scan is powerful in evaluating the functional characteristics of the tissues, CT is a powerful structural resolution imaging method. The highly sensitive PET scan detects the metabolic signal of actively growing cancer cells in the body and the CT scan provides a detailed picture of the internal anatomy that reveals sites, size and shape of cancer tissue. Alone, each imaging test has particular benefits and limitations but when the results of PET and CT scans are "fused" together, the combined image provides complete information on cancer location and metabolism.

  10. Evaluation of software tools for automated identification of neuroanatomical structures in quantitative β-amyloid PET imaging to diagnose Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Tuszynski, Tobias; Luthardt, Julia; Butzke, Daniel; Tiepolt, Solveig; Seese, Anita; Barthel, Henryk [Leipzig University Medical Centre, Department of Nuclear Medicine, Leipzig (Germany); Rullmann, Michael; Hesse, Swen; Sabri, Osama [Leipzig University Medical Centre, Department of Nuclear Medicine, Leipzig (Germany); Leipzig University Medical Centre, Integrated Treatment and Research Centre (IFB) Adiposity Diseases, Leipzig (Germany); Gertz, Hermann-Josef [Leipzig University Medical Centre, Department of Psychiatry, Leipzig (Germany); Lobsien, Donald [Leipzig University Medical Centre, Department of Neuroradiology, Leipzig (Germany)

    2016-06-15

    For regional quantification of nuclear brain imaging data, defining volumes of interest (VOIs) by hand is still the gold standard. As this procedure is time-consuming and operator-dependent, a variety of software tools for automated identification of neuroanatomical structures were developed. As the quality and performance of those tools are poorly investigated so far in analyzing amyloid PET data, we compared in this project four algorithms for automated VOI definition (HERMES Brass, two PMOD approaches, and FreeSurfer) against the conventional method. We systematically analyzed florbetaben brain PET and MRI data of ten patients with probable Alzheimer's dementia (AD) and ten age-matched healthy controls (HCs) collected in a previous clinical study. VOIs were manually defined on the data as well as through the four automated workflows. Standardized uptake value ratios (SUVRs) with the cerebellar cortex as a reference region were obtained for each VOI. SUVR comparisons between ADs and HCs were carried out using Mann-Whitney-U tests, and effect sizes (Cohen's d) were calculated. SUVRs of automatically generated VOIs were correlated with SUVRs of conventionally derived VOIs (Pearson's tests). The composite neocortex SUVRs obtained by manually defined VOIs were significantly higher for ADs vs. HCs (p=0.010, d=1.53). This was also the case for the four tested automated approaches which achieved effect sizes of d=1.38 to d=1.62. SUVRs of automatically generated VOIs correlated significantly with those of the hand-drawn VOIs in a number of brain regions, with regional differences in the degree of these correlations. Best overall correlation was observed in the lateral temporal VOI for all tested software tools (r=0.82 to r=0.95, p<0.001). Automated VOI definition by the software tools tested has a great potential to substitute for the current standard procedure to manually define VOIs in β-amyloid PET data analysis. (orig.)

  11. Controllable electrochemical synthesis of ZnO nanorod arrays on flexible ITO/PET substrate and their structural and optical properties

    International Nuclear Information System (INIS)

    Highlights: ► Vertically aligned ZnO nanorod arrays were grown on flexible transparent substrate by the electrodeposition. ► Morphology and optical properties were controlled by varying the deposition voltage and the concentration of growth solution. ► Crystallinity and photoluminescence were studied under different growth conditions. ► Well aligned ZnO nanorod arrays show the good antireflection and wetting properties. ► Optimized ZnO nanorod arrays exhibit an increased diffuse light scattering with keeping high transparency. - Abstract: The structural and optical properties of vertically aligned zinc oxide (ZnO) nanorod arrays (NRAs) which were grown on the flexible indium tin oxide (ITO) coated polyethylene terephthalate (PET) substrate (i.e., ITO/PET substrate) with a thin sputtered ZnO seed layer via the electrochemical deposition method were studied. By changing the applied voltage and zinc nitrate concentration, the height/width and density of ZnO NRAs were controlled, with investigation on their crystallinity and optical properties. To understand the effect of ZnO seed layer on the growth property of ZnO nanorods, they were also grown on ITO/PET without any seed layer. Under an applied cathodic voltage of −2 V and zinc nitrate concentration of 10 mM, the ZnO NRAs increased the total transmittance up to 88.7% in the visible wavelength region due to the antireflective property and their X-ray diffraction (0 0 2) peak intensity was largely enhanced. Additionally, the near band edge emission of ZnO was significantly enhanced in photoluminescence spectrum. The light scattering and surface wetting properties were also explored.

  12. PET studies of stroke

    International Nuclear Information System (INIS)

    PET already has been helpful in ischemic stroke disease. It has given us new data on physiological events occurring after a stroke; PET indices of blood flow and metabolism have provided the basis for staging the severity of tissue injury and predicting outcome, and PET has shown alterations in tissue function in response to therapy. Experience with PET in hemorrhagic disease is more limited, but initial results suggest a useful role for PET in the evaluation of nontraumatic intracranial hemorrhage as well [Ackerman et al., 1983a]. This brief review discusses general problems in the study of stroke disease using PET and then the contribution of PET to the stroke field

  13. 补体成分 C3及其缺失突变体蛋白的表达及与 CLIC1蛋白共定位的研究%The expression of human complement component C3 and its deletion mutants and the colocalization with CLIC1

    Institute of Scientific and Technical Information of China (English)

    王二宁; 陈丹丹; 刘晓颖; 范礼斌

    2015-01-01

    目的:研究补体成分 C3及其缺失突变体 C3(1-840)、C3(824-1663)在真核细胞内的表达及与氯离子通道蛋白(CLIC1)的共定位。方法构建 pcDNA3.1-C3-FLAG、pcDNA3.1-C3(1-840)-FLAG、pcDNA3.1-C3(824-1663)-FLAG 三个真核表达质粒(缺失突变体根据 C3的结构域及其裂解断裂位置设计),并分别转染至 HEK 293T 细胞中, Western blot 检测表达情况;上述质粒分别瞬时单转至 COS7细胞和分别与 GFP-CLIC1共转至 COS7细胞内,观察共定位情况。结果成功构建带 FLAG 标签的 C3基因及其两个缺失突变体[C3(1-840)、C3(824-1663)]的真核表达载体, Western blot 结果显示它们在 HEK 293T 细胞中均能成功表达;免疫荧光显示它们在 COS7细胞中均主要分布于细胞质,且三个真核表达载体中只有 C3(824-1663)与 CLIC1有共定位。结论补体 C3及其缺失突变体 C3(1-840)和 C3(824-1663)在 HEK 293T、COS7细胞中均能高效表达,且主要分布在细胞质内,C3(824-1663)与 CLIC1蛋白有共定位。%Objective To study the expression and cell localization of complement component C3 and its deletion mutants C3(1-840)and C3(824-1663)in eukaryotic cells and the colocalization with CLIC1.Methods To con-struct three eukaryotic expression plasmids of pcDNA3.1-C3-FLAG,pcDNA3.1-C3(1-840)-FLAG and pcDNA3.1-C3(824-1663)-FLAG(according to C3 structure domain and splitting position).The plasmids were transfected into HEK 293T cells.Then the expression was detected by Western blot,and their cellular localization was detected in COS7 cells by fluorescence microscopy.Results The eukaryotic expression plasmids of pcDNA3.1-C3-FLAG, pcDNA3.1-C3(1-840)-FLAG and pcDNA3.1-C3(824-1663)-FLAG were constructed successfully,which could be expressed in HEK 293T and COS7 cells,and the cellular localization of C3 and C3(1-840),C3(824-1663)ap-peared similar,mainly in the cytoplasm,and only C3(824-1663)co

  14. Beam Tests of a Prototype Stripline Beam Position Monitoring System for the Drive Beam of the CLIC Two-beam Module at CTF3

    CERN Document Server

    Benot-Morell, Alfonso; Nappa, Jean-Marc; Vilalte, Sebastien; Wendt, Manfred

    2016-01-01

    In collaboration with LAPP and IFIC, two units of a prototype stripline Beam Position Monitor (BPM) for the CLIC Drive Beam (DB), and its associated readout electronics have been successfully installed and tested in the Two-Beam-Module (TBM) at the CLIC Test Facility 3 (CTF3) at CERN. This paper gives a short overview of the BPM system and presents the performance measured under different Drive Beam configurations.

  15. CLIC5 stabilizes membrane-actin filament linkages at the base of hair cell stereocilia in a molecular complex with radixin, taperin, and myosin VI.

    Science.gov (United States)

    Salles, Felipe T; Andrade, Leonardo R; Tanda, Soichi; Grati, M'hamed; Plona, Kathleen L; Gagnon, Leona H; Johnson, Kenneth R; Kachar, Bechara; Berryman, Mark A

    2014-01-01

    Chloride intracellular channel 5 protein (CLIC5) was originally isolated from microvilli in complex with actin binding proteins including ezrin, a member of the Ezrin-Radixin-Moesin (ERM) family of membrane-cytoskeletal linkers. CLIC5 concentrates at the base of hair cell stereocilia and is required for normal hearing and balance in mice, but its functional significance is poorly understood. This study investigated the role of CLIC5 in postnatal development and maintenance of hair bundles. Confocal and scanning electron microscopy of CLIC5-deficient jitterbug (jbg) mice revealed progressive fusion of stereocilia as early as postnatal day 10. Radixin (RDX), protein tyrosine phosphatase receptor Q (PTPRQ), and taperin (TPRN), deafness-associated proteins that also concentrate at the base of stereocilia, were mislocalized in fused stereocilia of jbg mice. TPRQ and RDX were dispersed even prior to stereocilia fusion. Biochemical assays showed interaction of CLIC5 with ERM proteins, TPRN, and possibly myosin VI (MYO6). In addition, CLIC5 and RDX failed to localize normally in fused stereocilia of MYO6 mutant mice. Based on these findings, we propose a model in which these proteins work together as a complex to stabilize linkages between the plasma membrane and subjacent actin cytoskeleton at the base of stereocilia. PMID:24285636

  16. Proposition d'une méthode d'alignement de l'accélérateur linéaire CLIC

    CERN Document Server

    Touzé, Thomas; Mainaud-Durand, H

    2011-01-01

    The compact linear collider (CLIC) is the particles accelerator project proposed by the european organization for nuclear research (CERN) for high energy physics after the large hadron collider (LHC). Because of the nanometric scale of the CLIC leptons beams, the emittance growth budget is very tight. It induces alignment tolerances on the positions of the CLIC components that have never been achieved. The last step of the CLIC alignment will be done according to the beam itself. It falls within the competence of the physicists. However, in order to implement the beam-based feedback, a challenging pre-alignment is required : 10 μm at 3σ along a 200 m sliding window. For such a precision, the proposed solution must be compatible with a feedback between the measurement and repositioning systems. The CLIC pre-alignment will have to be active. This thesis does not demonstrate the feasibility of the CLIC active prealignment but shows the way to the last developments that have to be done for that purpose. A metho...

  17. The Climate and Cryosphere Project (CliC): Helping bring sea ice Models and Observations together.

    Science.gov (United States)

    Lytle, V.; Goodison, B.; Worby, A.; Ryabinin, V.; Prick, A.; Villinger, T.

    2007-12-01

    The Climate and Cryosphere Project is sponsored by the World Climate Research Program (WCRP) and the Scientific Committee for Antarctic Research (SCAR). One of the four themes within the CliC project is the Marine Cryosphere Theme (MarC). This paper will review the recent projects and workshops held within this Theme and how they relate to other, international initiatives. Recent recommendations on sea ice thickness are being implemented, and groups have been formed to work towards improvements in models, particularly in their representation of the Southern Ocean. SOPHOCLES (Southern Ocean Physical Oceanography and Cryosphere Processes and Climate) will work with other modeling groups to improve the representation of the Southern Ocean in climate models. This will include cooperation with other modeling and observational groups to develop metrics to help evaluate models. In the Arctic, we are working to help develop, standardize, and implement observation and measurement protocols for Arctic sea ice in coastal, seasonal, and perennial ice zones.

  18. Measurements and Laboratory Tests on a Prototype Stripline Kicker for the CLIC Damping Rings

    CERN Document Server

    Belver-Aguilar, C; Toral, F; Barnes, MJ; Day, H

    2014-01-01

    The Pre-Damping Rings (PDRs) and Damping Rings (DRs) of CLIC are required to reduce the beam emittances to the small values required for the main linacs. The injection and extraction, from the PDRs and DRs, are performed by kicker systems. To achieve both low beam coupling impedance and reasonable broadband impedancematching to the electrical circuit, striplines have been chosen for the kicker elements. Prototype striplines have been built: tests and measurements of these striplines have started. The goal of these tests is to characterize, without beam, the electromagnetic response of the striplines. The tests have been carried out at CERN. To study the signal transmission through the striplines, the measured S-parameters have been compared with simulations. In addition, measurements of longitudinal beam coupling impedance, using the coaxial wire method, are reported and compared with simulations.

  19. Simulation Study of Cool-Down of the CLIC Wiggler Magnets

    CERN Document Server

    Liu, L; van Weelderen, R; Xiong, L

    2013-01-01

    The cryogenic system for the CLIC wiggler magnets is under design. The cooldown process is one of the main dimensioning factors for the system. In this paper, the heat transfer model used to simulate the cool-down process is presented. Different configurations are then investigated and a detailed analysis of the corresponding temperature evolutions along the magnet strings is calculated. The temperature profiles are evaluated for the flowing helium as well as for the magnets allowing a detailed analysis of the temperature gradients. The impact of some key parameters, like the mass-flow rate, the diameter of the cooling channels and of the thermal coupling between the helium and the magnets is also investigated.

  20. Present status of development of damping ring extraction kicker system for CLIC

    CERN Document Server

    Holma, Janne; Belver-Aguilar, Caroline; Faus-Golfe, Angeles; Toral, Fernando

    2012-01-01

    The CLIC damping rings will produce ultra-low emittance beam, with high bunch charge, necessary for the luminosity performance of the collider. To limit the beam emittance blow-up due to oscillations, the pulse power modulators for the damping ring kickers must provide extremely flat, high-voltage pulses: specifications call for a 160 ns duration and a flattop of 12.5 kV, 250 A, with a combined ripple and droop of not more than \\pm0.02 %. The stripline design is also extremely challenging: the field for the damping ring kicker system must be homogenous to within \\pm0.01 % over a 1 mm radius, and low beam coupling impedance is required. The solid-state modulator, the inductive adder, is a very promising approach to meeting the demanding specifications for the field pulse ripple and droop. This paper describes the initial design of the inductive adder and the striplines of the kicker system.

  1. Present status of development of damping ring extraction kicker system for CLIC

    CERN Document Server

    Holma, Janne; Belver-Aguilar, Caroline; Faus-Golfe, Angeles; Toral, Fernando

    2012-01-01

    The CLIC damping rings will produce ultra-low emittance beam, with high bunch charge, necessary for the luminosity performance of the collider. To limit the beam emittance blow-up due to oscillations, the pulse power modulators for the damping ring kickers must provide extremely flat, high-voltage pulses: specifications call for a 160 ns duration and a flattop of 12.5 kV, 250 A, with a combined ripple and droop of not more than ±0.02 %. The stripline design is also extremely challenging: the field for the damping ring kicker system must be homogenous to within ±0.01 % over a 1 mm radius, and low beam coupling impedance is required. The solid-state modulator, the inductive adder, is a very promising approach to meeting the demanding specifications for the field pulse ripple and droop. This paper describes the initial design of the inductive adder and the striplines of the kicker system.

  2. Stabilization and positioning of CLIC quadrupole magnets with sub-nanometre resolution

    CERN Document Server

    Janssens, S; Collette, C; Esposito, M; Fernandez Carmona, P; Guinchard, M; Hauviller, C; Kuzmin, A; Leuxe, R; Moron Ballester, R

    2011-01-01

    To reach the required luminosity at the CLIC interaction point, about 2000 quadrupoles along each linear collider are needed to obtain a vertical beam size of 1 nm at the interaction point. Active mechanical stabilization is required to limit the vibrations of the magnetic axis to the nanometre level in a frequency range from 1 to 100 Hz. The approach of a stiff actuator support was chosen to isolate from ground motion and technical vibrations acting directly on the quadrupoles. The actuators can also reposition the quadrupoles between beam pulses with nanometre resolution. A first conceptual design of the active stabilization and nano positioning based on the stiff support and seismometers was validated in models and experimentally demonstrated on test benches. Lessons learnt from the test benches and information from integrated luminosity simulations using measured stabilization transfer functions lead to improvements of the actuating support, the sensors used and the system controller. The controller elect...

  3. Z′ Resonance and Associated Zh Production at Future Higgs Boson Factory: ILC and CLIC

    International Nuclear Information System (INIS)

    We study the prospects of the B-L model with an additional Z′ boson to be a Higgs boson factory at high-energy and high-luminosity linear electron positron colliders, such as the ILC and CLIC, through the Higgs-strahlung process e+e-→(Z,Z′)→Zh, including both the resonant and the nonresonant effects. We evaluate the total cross section of Zh and we calculate the total number of events for integrated luminosities of 500–2000 fb−1 and center of mass energies between 500 and 3000 GeV. We find that the total number of expected Zh events can reach 106, which is a very optimistic scenario and it would be possible to perform precision measurements for both Z′ and Higgs boson in future high-energy e+e- colliders experiments

  4. Z′ Resonance and Associated Zh Production at Future Higgs Boson Factory: ILC and CLIC

    Directory of Open Access Journals (Sweden)

    A. Gutiérrez-Rodríguez

    2015-01-01

    Full Text Available We study the prospects of the B-L model with an additional Z′ boson to be a Higgs boson factory at high-energy and high-luminosity linear electron positron colliders, such as the ILC and CLIC, through the Higgs-strahlung process e+e-→(Z,Z′→Zh, including both the resonant and the nonresonant effects. We evaluate the total cross section of Zh and we calculate the total number of events for integrated luminosities of 500–2000 fb−1 and center of mass energies between 500 and 3000 GeV. We find that the total number of expected Zh events can reach 106, which is a very optimistic scenario and it would be possible to perform precision measurements for both Z′ and Higgs boson in future high-energy e+e- colliders experiments.

  5. CLIC simulations from the start of the linac to the interaction point

    CERN Document Server

    Schulte, Daniel; Blair, G A; D'Amico, T E; Leros, Nicolas; Redaelli, S; Risselada, Thys; Zimmermann, Frank

    2002-01-01

    Simulations for linear colliders are traditionally performed separately for the different sub-systems, like damping ring, bunch compressor, linac, and beam delivery. The beam properties are usually passed from one sub-system to the other via bunch charge, RMS transverse emittances, RMS bunch length, average energy and RMS energy spread. It is implicitly assumed that the detailed 6D correlations in the beam distribution are not relevant for the achievable luminosity. However, it has recently been shown that those correlations can have a strong effect on the beam-beam interaction. We present first results on CLIC simulations that integrate linac, beam delivery, and beam-beam interaction. These integrated simulations also allow a better simulation of time-dependent effects, like ground perturbations and interference between several beam-based feedbacks.

  6. A closer look at the beam-beam processes at ILC and CLIC

    CERN Document Server

    Hartin, Anthony

    2012-01-01

    The strength of the electromagnetic fields in the bunch collision at a linear collider will have a significant effect, yielding large numbers of beamstrahlung photons and associated coherent pair production. These effects are limited in the proposed ILC beam parameters which limit the strength of the bunch field to $\\Upsilon_{\\text{ave}}=0.27$. The CLIC 3 Tev design by comparison has a $\\Upsilon_{\\text{ave}}=3.34$ yielding huge number of coherent pairs. In terms of the precision physics programs of these proposed colliders there is an imperative to investigate the effect of the strong bunch fields on higher order processes. From the exact wavefunctions used in the calculation of transition rates within the Furry interaction picture, and using appropriate simplifications, a multiplicative factor to the coupling constants was obtained. This indicates a significant variation to the transition rate near threshold energies. Further studies are in progress to calculate the exact effect on expected observables.

  7. Physics potential of the BR(H →WW∗) measurement at a √s=350 GeV and √s=1.4 TeV CLIC collider

    CERN Document Server

    Pandurovic, Mila

    2016-01-01

    Precision measurements of the number of properties of the Higgs boson, like invariant mass and couplings to the Standard Model particles, represent one of the key measurements of the CLIC physic program. The CLIC energy staging scenario allows to perform these meas- urements using different Higgs production channels. The Higgs decay to a WW pair, which is analysed at two CLIC energy stages, plays an important role in this program, as it gives access to the relative Higgs couplings to the vector bosons and to the total Higgs decay width. The studies presented here are part of an ongoing effort to investigate the full physics potential of the CLIC collider.

  8. PET / MRI vs. PET / CT. Indications Oncology

    International Nuclear Information System (INIS)

    Hybrid techniques in Nuclear Medicine is currently a field in full development for diagnosis and treatment of various medical conditions. With the recent advent of PET / MRI much it speculated about whether or not it is superior to PET / CT especially in oncology. The Conference seeks to clarify this situation by dealing issues such as: State of the art technology PET / MRI; Indications Oncology; Some clinical cases. It concludes by explaining the oncological indications of both the real and current situation of the PET / MRI. (author)

  9. Heart PET scan

    Science.gov (United States)

    ... nuclear medicine scan; Heart positron emission tomography; Myocardial PET scan ... A PET scan requires a small amount of radioactive material (tracer). This tracer is given through a vein (IV), ...

  10. Clinical PET application

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sang-Moo; Hong, S. W.; Choi, C. W.; Yang, S. D.; Choi, J. S.; Kweon, O. J. et al. [Korea Cancer Center Hospital, Seoul (Korea)

    2000-12-01

    PET gives various metabolic images, and is very important, new diagnostic modality in clinical oncology. In Korea Cancer Center Hospital, PET is installed as a research tool of long-mid-term atomic research project. For the efficient use of PET for clinical and research projects, income from the patients should be managed to get the raw material, equipment, manpower, and also for the clinical PET research. 1. Support the clinical application of PET in oncology. 2. Budgetary management of income, costs for raw material, equipment, manpower, and the clinical PET research project. In this year, 1,327 cases of PET images were obtained, which resulted total income of 829,770,000won. Increased demand for {sup 18}FDG in and outside KCCH need more than 2 times production of {sup 18} in a day. Manpower should be added for the second PET operation and RI production. 10 figs., 4 tabs. (Author)

  11. Impact of the New CLIC Beam Parameters on the Design of the Post-Collision Line and its Exit Window

    CERN Document Server

    Ferrari, A

    2008-01-01

    Following the recent modification of the CLIC beam parameters, we present an updated design of the post-collision line. As a result of the increase of the beamstrahlung photon cone size, the separation of the outgoing beams by the vertical magnetic chicane is more difficult, but still possible. The main changes in the post-collision line design include the implementation of a common dump for the wrong-sign charged particles of the coherent pairs and for the low-energy tails of the disrupted beam, as well as a significant reduction of the overall lattice length (allowing removal of the large refocusing quadrupoles). The thermal and mechanical stresses in the new exit window, 150 m downstream of the interaction point, were computed. We conclude that, despite the recent changes of the CLIC beam parameters and the necessary modifications of the post-collision line and its exit window, their performance is not significantly affected.

  12. Design of the 15 GHz BPM test bench for the CLIC test facility to perform precise stretchedwire RF measurements

    CERN Document Server

    Silvia Zorzetti, Silvia; Galindo Muño, Natalia; Wendt, Manfred

    2015-01-01

    The Compact Linear Collider (CLIC) requires a low emittance beam transport and preservation, thus a precise control of the beam orbit along up to 50 km of the accelerator components in the sub-m regime is required. Within the PACMAN3 (Particle Accelerator Components Metrology and Alignment to the Nanometer Scale) PhD training action a study with the objective of pre-aligning the electrical centre of a 15 GHz cavity beam position monitor (BPM) to the magnetic centre of the main beam quadrupole is initiated. Of particular importance is the design of a specific test bench to study the stretched-wire setup for the CLIC Test Facility (CTF3) BPM, focusing on the aspects of microwave signal excitation, transmission and impedance-matching, as well as the mechanical setup and reproducibility of the measurement method.

  13. Accelerator and Technical Sector Seminar: Mechanical stabilization and positioning of CLIC quadrupoles with sub-nanometre resolution

    CERN Multimedia

    2011-01-01

    Thursday 24 November 2010 Accelerator and Technical Sector Seminar at 14:15  -  BE Auditorium, bldg. 6 (Meyrin) – please note unusual place Mechanical stabilization and positioning of CLIC quadrupoles with sub-nanometre resolution Stef Janssens /EN-MME Abstract: To reach the required luminosity at the CLIC interaction point, about 4000 quadrupoles are needed to obtain a vertical beam size of 1 nm at the interaction point. The mechanical jitter of the quadrupole magnets will result in an emittance growth. An active vibration isolation system is required to reduce vibrations from the ground and from external forces to about 1.5 nm integrated root mean square (r.m.s.) vertical displacement at 1 Hz. A short overview of vibration damping and isolation strategies will be presented as well as a comparison of existing systems. The unprecedented resolution requirements and the instruments enabling these measurements will be discussed. The vibration sources from which the magnets need to...

  14. CLIC-ACM: generic modular rad-hard data acquisition system based on CERN GBT versatile link

    International Nuclear Information System (INIS)

    CLIC is a world-wide collaboration to study the next ''terascale'' lepton collider, relying upon a very innovative concept of two-beam-acceleration. This accelerator, currently under study, will be composed of the subsequence of 21000 two-beam-modules. Each module requires more than 300 analogue and digital signals which need to be acquired and controlled in a synchronous way. CLIC-ACM (Acquisition and Control Module) is the 'generic' control and acquisition module developed to accommodate the controls of all these signals for various sub-systems and related specification in term of data bandwidth, triggering and timing synchronization. This paper describes the system architecture with respect to its radiation-tolerance, power consumption and scalability

  15. DICOM for quantitative imaging biomarker development: a standards based approach to sharing clinical data and structured PET/CT analysis results in head and neck cancer research

    Science.gov (United States)

    Clunie, David; Ulrich, Ethan; Bauer, Christian; Wahle, Andreas; Brown, Bartley; Onken, Michael; Riesmeier, Jörg; Pieper, Steve; Kikinis, Ron; Buatti, John; Beichel, Reinhard R.

    2016-01-01

    Background. Imaging biomarkers hold tremendous promise for precision medicine clinical applications. Development of such biomarkers relies heavily on image post-processing tools for automated image quantitation. Their deployment in the context of clinical research necessitates interoperability with the clinical systems. Comparison with the established outcomes and evaluation tasks motivate integration of the clinical and imaging data, and the use of standardized approaches to support annotation and sharing of the analysis results and semantics. We developed the methodology and tools to support these tasks in Positron Emission Tomography and Computed Tomography (PET/CT) quantitative imaging (QI) biomarker development applied to head and neck cancer (HNC) treatment response assessment, using the Digital Imaging and Communications in Medicine (DICOM®) international standard and free open-source software. Methods. Quantitative analysis of PET/CT imaging data collected on patients undergoing treatment for HNC was conducted. Processing steps included Standardized Uptake Value (SUV) normalization of the images, segmentation of the tumor using manual and semi-automatic approaches, automatic segmentation of the reference regions, and extraction of the volumetric segmentation-based measurements. Suitable components of the DICOM standard were identified to model the various types of data produced by the analysis. A developer toolkit of conversion routines and an Application Programming Interface (API) were contributed and applied to create a standards-based representation of the data. Results. DICOM Real World Value Mapping, Segmentation and Structured Reporting objects were utilized for standards-compliant representation of the PET/CT QI analysis results and relevant clinical data. A number of correction proposals to the standard were developed. The open-source DICOM toolkit (DCMTK) was improved to simplify the task of DICOM encoding by introducing new API abstractions

  16. DICOM for quantitative imaging biomarker development: a standards based approach to sharing clinical data and structured PET/CT analysis results in head and neck cancer research.

    Science.gov (United States)

    Fedorov, Andriy; Clunie, David; Ulrich, Ethan; Bauer, Christian; Wahle, Andreas; Brown, Bartley; Onken, Michael; Riesmeier, Jörg; Pieper, Steve; Kikinis, Ron; Buatti, John; Beichel, Reinhard R

    2016-01-01

    Background. Imaging biomarkers hold tremendous promise for precision medicine clinical applications. Development of such biomarkers relies heavily on image post-processing tools for automated image quantitation. Their deployment in the context of clinical research necessitates interoperability with the clinical systems. Comparison with the established outcomes and evaluation tasks motivate integration of the clinical and imaging data, and the use of standardized approaches to support annotation and sharing of the analysis results and semantics. We developed the methodology and tools to support these tasks in Positron Emission Tomography and Computed Tomography (PET/CT) quantitative imaging (QI) biomarker development applied to head and neck cancer (HNC) treatment response assessment, using the Digital Imaging and Communications in Medicine (DICOM(®)) international standard and free open-source software. Methods. Quantitative analysis of PET/CT imaging data collected on patients undergoing treatment for HNC was conducted. Processing steps included Standardized Uptake Value (SUV) normalization of the images, segmentation of the tumor using manual and semi-automatic approaches, automatic segmentation of the reference regions, and extraction of the volumetric segmentation-based measurements. Suitable components of the DICOM standard were identified to model the various types of data produced by the analysis. A developer toolkit of conversion routines and an Application Programming Interface (API) were contributed and applied to create a standards-based representation of the data. Results. DICOM Real World Value Mapping, Segmentation and Structured Reporting objects were utilized for standards-compliant representation of the PET/CT QI analysis results and relevant clinical data. A number of correction proposals to the standard were developed. The open-source DICOM toolkit (DCMTK) was improved to simplify the task of DICOM encoding by introducing new API abstractions

  17. FDG-PET standardized uptake values in normal anatomical structures using iterative reconstruction segmented attenuation correction and filtered back-projection

    International Nuclear Information System (INIS)

    Filtered back-projection (FBP) is the most commonly used reconstruction method for PET images, which are usually noisy. The iterative reconstruction segmented attenuation correction (IRSAC) algorithm improves image quality without reducing image resolution. The standardized uptake value (SUV) is the most clinically utilized quantitative parameter of [fluorine-18]fluoro-2-deoxy-d-glucose (FDG) accumulation. The objective of this study was to obtain a table of SUVs for several normal anatomical structures from both routinely used FBP and IRSAC reconstructed images and to compare the data obtained with both methods. Twenty whole-body PET scans performed in consecutive patients with proven or suspected non-small cell lung cancer were retrospectively analyzed. Images were processed using both IRSAC and FBP algorithms. Nonquantitative or gaussian filters were used to smooth the transmission scan when using FBP or IRSAC algorithms, respectively. A phantom study was performed to evaluate the effect of different filters on SUV. Maximum and average SUVs (SUVmax and SUVavg) were calculated in 28 normal anatomical structures and in one pathological site. The phantom study showed that the use of a nonquantitative smoothing filter in the transmission scan results in a less accurate quantification and in a 20% underestimation of the actual measurement. Most anatomical structures were identified in all patients using the IRSAC images. On average, SUVavg and SUVmax measured on IRSAC images using a gaussian filter in the transmission scan were respectively 20% and 8% higher than the SUVs calculated from conventional FBP images. Scatterplots of the data values showed an overall strong relationship between IRSAC and FBP SUVs. Individual scatterplots of each site demonstrated a weaker relationship for lower SUVs and for SUVmax than for higher SUVs and SUVavg. A set of reference values was obtained for SUVmax and SUVavg of normal anatomical structures, calculated with both IRSAC and FBP

  18. How PET is changing the management of cancer with radiotherapy

    International Nuclear Information System (INIS)

    Information from PET scanning is transforming the management of many malignancies and the impact of PET is likely to increase further as new indications are recognised. PET is of particular value in patients treated with radiotherapy (RT) with curative intent. These patients rarely undergo invasive surgical staging and therefore imaging is crucial in determining the extent of disease before treatment. More accurate staging with PET means that futile aggressive RT or chcmoRT can be avoided in patients with incurable extensive disease. FDG-PET is of proven value in the staging of common metabolically-active malignancies treated with radiotherapy. These include lung cancer, head and neck cancer, lymphomas and oesophageal carcinoma. It has been shown that PET can improve the selection of patients for radical surgery or radiotherapy in lung cancer and that PET-based staging more accurately predicts survival than conventional staging. For those patients that remain eligible for definitive RT after PET. treatment can be more accurately targeted at the tumour and involved regional nodes. The value of PET for treatment planning is enhanced significantly when PET and CT scans are acquired on a combined PET/CT scanner. Fused PET-CT images can be imported into the radiotherapy planning computer and used to accurately target tumour with the best beam arrangement. After treatment, response may be hard to assess with structural imaging. PET-rcsponse to chemotherapy or radiotherapy in non-small cell lung cancer (NSCLC) predicts survival in NSCLC more accurately than CT response. However, PET has much more potential than imaging with FDG alone can realise. Markers such as FLT can be used to image proliferation in tumours, misonidazole or FAZA can be used to image hypoxia and labeled metabolites of anti-cancer drugs such as 5-FU can be used to study pharmacokinetics. New combinations of radiation and drugs may emerge that can be selected based on biological characteristics of

  19. PET in oncology

    Energy Technology Data Exchange (ETDEWEB)

    Dresel, Stefan (ed.) [HELIOS Klinikum Berlin-Buch, Berlin (Germany). Klinik fuer Nuklearmedizin

    2008-07-01

    In the management of oncologic diseases, modern imaging modalities contribute heavily to the decision of which form of treatment - local or systemic, surgical or interdisciplinary - will be most efficient. The addition of functional image information to conventional staging procedures helps improve the diagnostic pathway. The information needed for therapeutic management and for follow-up can be provided by correlative imaging such as positron emission tomography (PET) and computed tomography (CT) or PET/CT. This book is a comprehensive compilation of the accumulated knowledge on PET and PET/CT in oncology, covering the entire spectrum from solidly documented indications, such as staging and monitoring of lung and colorectal cancer, to the application of PET/CT in head and neck surgery, gynecology, radiation therapy, urology, pediatrics etc. It is aimed at nuclear medicine and radiology specialists as well as physicians interested in the possibilities and limitations of PET and PET/CT in oncology. (orig.)

  20. Hybrid registration of PET/CT in thoracic region with pre-filtering PET sinogram

    Science.gov (United States)

    Mokri, S. S.; Saripan, M. I.; Marhaban, M. H.; Nordin, A. J.; Hashim, S.

    2015-11-01

    The integration of physiological (PET) and anatomical (CT) images in cancer delineation requires an accurate spatial registration technique. Although hybrid PET/CT scanner is used to co-register these images, significant misregistrations exist due to patient and respiratory/cardiac motions. This paper proposes a hybrid feature-intensity based registration technique for hybrid PET/CT scanner. First, simulated PET sinogram was filtered with a 3D hybrid mean-median before reconstructing the image. The features were then derived from the segmented structures (lung, heart and tumor) from both images. The registration was performed based on modified multi-modality demon registration with multiresolution scheme. Apart from visual observations improvements, the proposed registration technique increased the normalized mutual information index (NMI) between the PET/CT images after registration. All nine tested datasets show marked improvements in mutual information (MI) index than free form deformation (FFD) registration technique with the highest MI increase is 25%.

  1. Salmonella: Dry Pet Foods and Pet Treats (FAQ)

    Science.gov (United States)

    ... Guides Reports Salmonella: Dry Pet Foods and Pet Treats (FAQ) Originally posted August 9, 2010; Updated August ... as a result of the outbreak. “Natural” pet treats , such as pig ears and dehydrated/dried beef ...

  2. High Frequency Effects of Impedances and Coatings in the CLIC Damping Rings

    CERN Document Server

    Koukovini Platia, Eirini; Rumolo, G

    The Compact Linear Collider (CLIC) is a 3 TeV eÅe¡ machine, currently under design at CERN, that targets to explore the terascale particle physics regime. The experiment requires a high luminosity of 2£1034 cm2 s¡1, which can be achieved with ultra low emittances delivered from the Damping Rings (DRs) complex. The high bunch brightness of the DRs gives rise to several collective effects that can limit the machine performance. Impedance studies during the design stage of the DR are of great importance to ensure safe operation under nominal parameters. As a first step, the transverse impedance model of the DRis built, accounting for the wholemachine. Beam dynamics simulations are performedwith HEADTAIL to investigate the effect on beam dynamics. For the correct impedancemodeling of the machine elements, knowledge of the material properties is essential up to hundreds of GHz, where the bunch spectrum extends. Specifically, Non Evaporable Getter (NEG) is a commonly used coating for good vacuumbut its properti...

  3. Instrumentation for Longitudinal Beam Gymnastics in FEL's and at the CLIC Test Facility 3

    CERN Document Server

    Lefèvre, T; Bravin, E; Burger, S; Corsini, R; Döbert, S; Soby, L; Tecker, F A; Urschutz, P; Welsch, C P; Alesini, D; Biscari, C; Buonomo, B; Coiro, O; Ghigo, A; Marcellini, F; Preger, B; Dabrowski, A; Velasco, M; Craievich, P; Ferianis, M; Veronese, M; Ferrari, A

    2008-01-01

    Built at CERN by an international collaboration, the CLIC Test Facility 3 (CTF3) aims at demonstrating the feasibility of a high luminosity 3 TeV e+-e- collider by the year 2010. One of the main issues to be demonstrated is the generation of a high average current (30 A) high frequency (12 GHz) bunched beam by means of RF manipulation. At the same time, Free Electron Lasers (FEL) are developed in several places all over the world with the aim of providing high brilliance photon sources. These machines rely on the production of high peak current electron bunches. The required performances put high demands on the diagnostic equipment and innovative longitudinal monitors have been developed during the past years. This paper gives an overview of the longitudinal instrumentation developed at ELETTRA and CTF3, where a special effort was made in order to implement at the same time non-intercepting devices for online monitoring, and destructive diagnostics which have the advantage of providing more detailed informati...

  4. Transverse Beam Polarizationas an Alternate View into New Physics at CLIC

    Energy Technology Data Exchange (ETDEWEB)

    Rizzo, Thomas G.; /SLAC

    2011-08-12

    In e{sup +}e{sup -} collisions, transverse beam polarization can be a useful tool in studying the properties of particles associated with new physics beyond the Standard Model(SM). However, unlike in the case of measurements associated with longitudinal polarization, the formation of azimuthal asymmetries used to probe this physics in the case of transverse polarization requires both e{sup {+-}} beams to be simultaneously polarized. In this paper we discuss the further use of transverse polarization as a probe of new physics models at a high energy, {radical}s = 3 TeV version of CLIC. In particular, we show (i) how measurements of the sign of these asymmetries is sufficient to discriminate the production of spin-0 supersymmetric states from the spin-1/2 Kaluza-Klein excitations of Universal Extra Dimensions. Simultaneously, the contribution to this asymmetry arising from the potentially large SM W{sup +}W{sup -} background can be made negligibly small. We then show (ii) how measurements of such asymmetries and their associated angular distributions on the peak of a new resonant Z{prime}-like state can be used to extract precision information on the Z{prime} couplings to the SM fermions.

  5. Development and Validation of a Multipoint Based Laser Alignment System for CLIC

    CERN Document Server

    Stern, G; Lackner, F; Mainaud-Durand, H; Piedigrossi, D; Sandomierski, J; Sosin, M; Geiger, A; Guillaume, S

    2013-01-01

    Alignment is one of the major challenges within CLIC study, since all accelerator components have to be aligned with accuracy up to 10 μm over sliding windows of 200 m. So far, the straight line reference concept has been based on stretched wires coupled with Wire Positioning Sensors. This concept should be validated through inter-comparison with an alternative solution. This paper proposes an alternative concept where laser beam acts as straight line reference and optical shutters coupled with cameras visualise the beam. The principle was first validated by a series of tests using low-cost components. Yet, in order to further decrease measurement uncertainty in this validation step, a high-precision automatised micrometric table and reference targets have been added to the setup. The paper presents the results obtained with this new equipment, in terms of measurement precision. In addition, the paper gives an overview of first tests done at long distance (up to 53 m), having emphasis on beam divergence

  6. A Gas-Jet Profile Monitor for the CLIC Drive Beam

    CERN Document Server

    Jeff, A; Lefevre, T; Tzoganis, V; Welsch, C P

    2013-01-01

    The Compact Linear Collider (CLIC) will use a novel acceleration scheme in which energy extracted from a very intense beam of relatively low-energy electrons (the Drive Beam) is used to accelerate a lower intensity Main Beam to very high energy. The high intensity of the Drive Beam, with pulses of more than 1015 electrons, poses a challenge for conventional profile measurements such as wire scanners. Thus, new non-invasive profile measurements are being investigated. Profile monitors using gas ionisation or fluorescence have been used at a number of accelerators. Typically, extra gas must be injected at the monitor and the rise in pressure spreads for some distance down the beam pipe. In contrast, a gas jet can be fired across the beam into a receiving chamber, with little gas escaping into the rest of the beam pipe. In addition, a gas jet shaped into a thin plane can be used like a screen on which the beam crosssectionis imaged. In this paper we present some arrangements for the generation of such a jet. In ...

  7. Studies of Cs3Sb cathodes for the CLIC drive beam photo injector option

    CERN Document Server

    Martini, Irene; Doebert, Steffen; Fedosseev, Valentine; Hessler, Christoph; Martyanov, Mikhail

    2013-01-01

    Within the CLIC (Compact Linear Collider) project, feasibility studies of a photo injector option for the drive beam as an alternative to its baseline design using a thermionic electron gun are on-going. This R&D program covers both the laser and the photocathode side. Whereas the available laser pulse energy in ultra-violet (UV) is currently limited by the optical defects in the 4thharmonics frequency conversion crystal induced by the0.14 ms long pulse trains, recent measurements of Cs3Sbphotocathodes sensitive to green light showed their potential to overcome this limitation. Moreover, using visible laser beams leads to better stability of produced electron bunches and one can take advantages of the availability of higher quality optics. The studied Cs3Sbphotocathodes have been produced in the CERN photo emission laboratory using the co-deposition technique and tested in a DC gun set-up. The analysis of data acquired during the cathode production process will be presented in this paper, as well as the r...

  8. The effect of working pressure on the chemical bond structure and hydrophobic properties of PET surface treated by N ion beams bombardment

    International Nuclear Information System (INIS)

    Polyethylene terephthalate (PET) surface was bombarded by N ion beams at room temperature. Varying the working pressure of the ion beams, PET surfaces with different composition and properties were obtained. Characterization by X-ray photoelectron spectrometry showed that only on film surface, ester bonds, especially C-O bonds, were broken and N element chemical bonded with C. The influence depth was less than 5 nm because of the lower ion energy (about 103 eV). Contact angle results revealed that with increasing the working pressure of ion beams, the contact angle of PET surface to pure water increased from 51 deg. to 130 deg.. With these results, one conclusion could be deduced that the hydrophilic and hydrophobic properties of PET surface could be influenced by N atom chemical bond with C, which in turn is controlled by the working pressure of N ion beams.

  9. Clinical PET application

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sang Moo; Hong, Song W.; Choi, Chang W.; Yang, Seong Dae [Korea Cancer Center Hospital, Seoul (Korea)

    1997-12-01

    PET gives various methabolic images, and is very important, new diagnostic modality in clinical oncology. In Korea Cancer Center Hospital, PET is installed as a research tool of long-mid-term atomic research project. For the efficient use of PET for clinical and research projects, income from the patients should be managed to get the raw material, equipment, manpower, and also for the clinical PET research. 1. Support the clinical application of PET in oncology. 2. Budgetary management of income, costs for raw material, equipment, manpower, and the clinical PET research project. In this year, 250 cases of PET images were obtained, which resulted total income of 180,000,000 won. 50,000,000 won was deposited for the 1998 PET clinical research. Second year PET clinical research should be managed under unified project. Increased demand for {sup 18}FDG in and outside KCCH need more than 2 times production of {sup 18}FDG in a day purchase of HPLC pump and {sup 68}Ga pin source which was delayed due to economic crisis, should be done early in 1998. (author). 2 figs., 3 tabs.

  10. TRANSESTERIFICATION IN POLYPHENYLSILSISQUIOXANE (PPSQ)/POLY ETHYLENE TEREPHTHALATE (PET) BLENDS

    Institute of Scientific and Technical Information of China (English)

    LI Guizhi; SHI Lianghe; YE Meiling; ZHAO Chuntian; XU Mao

    1995-01-01

    The chemical structure of copolymer formed in the transesterification of PPSQ/PET blends during melt-processing is deduced from the 1H-NMR spectra. The transesterification extent of this blend is interpreted by the changes of crystalline melting peak in DSC thermograms of the insoluble products containing unreacted PET and some block PPSQ segments. Effects of composition of blend ladderlike regularity of PPSQ on the reaction extent have also been discussed.Inclusion of some block PPSQ segments in PET has no influence on the crystalline morphology of PET.

  11. HIV and pet ownership.

    Science.gov (United States)

    Downing, D

    1995-01-01

    The Centers for Disease Control and Prevention (CDC) states that there is no evidence that dogs, cats or non-primate animals can contract the human immunodeficiency virus (HIV) or transmit it to human beings. When the immune system is suppressed through disease, age, or medical treatments, a person becomes more vulnerable to infections. Pets Are Wonderful Support (PAWS) has developed guidelines for having pets. Proper pet selection, proper pet care and good personal hygiene of the owner can eliminate almost any possible risk a pet poses. New pets pose more of a health risk because health history and vaccination records are usually not known. Adult pets are often safer, and are less likely to be involved in playful activities that include biting and scratching. There is a slim chance of contracting toxoplasmosis from cats, but certain precautions can minimize risk. Annual veterinarian examinations are recommended to keep vaccinations current. The CDC does not recommend keeping a cat with feline leukemia virus or feline immunodeficiency virus since these diseases can make the cat more susceptible to other illnesses which can be passed on to a person with a compromised immune system. Turtles and birds are not recommended since they may harbor diseases. Several services are available to pet owners and are listed in the article. PMID:11362398

  12. My Pet Rock

    Science.gov (United States)

    Lark, Adam; Kramp, Robyne; Nurnberger-Haag, Julie

    2008-01-01

    Many teachers and students have experienced the classic pet rock experiment in conjunction with a geology unit. A teacher has students bring in a "pet" rock found outside of school, and the students run geologic tests on the rock. The tests include determining relative hardness using Mohs scale, checking for magnetization, and assessing luster.…

  13. PET and PET/CT for imaging of prostate cancer

    International Nuclear Information System (INIS)

    This review article provides an overview of the current literature data regarding the value of PET and PET/CT for imaging of prostate cancer. Most widely used PET tracers for prostate cancer imaging are 11C-acetate and 11C- or 18F-labeled choline. Available literature data on the performance of PET and PET/CT in the detection of the primary malignancy as well as local or distant metastases are presented and discussed. In addition, our own preliminary results regarding the diagnostic efficacy of 11C-choline PET and PET/CT in 43 patients with suspected prostate cancer are provided. The prevalence of prostate cancer in this patient sample was 55.8%. PET and PET/CT showed a sensitivity of 88% with a specificity of 63% in the detection of the primary prostate cancer. The sensitivity in the detection of metastatic spread was 77% and no false-positives were found. The possible value and limitations of combined PET/CT systems when compared to stand alone PET scanners are discussed. PET and PET/CT is at present the single imaging modality providing functional information not only regarding the primary malignancy but also its metastases. This unique feature distinguishes PET from MRI complemented with magnetic resonance spectroscopy - a competing procedure. Our own results as well as the still limited literature data suggest, that PET and PET/CT may prove to be useful methods for imaging of prostate cancer. (orig.)

  14. Usage of Recycled Pet

    Directory of Open Access Journals (Sweden)

    A. Ebru Tayyar

    2010-01-01

    Full Text Available The increasing industrialization, urbanization and the technological development have caused to increase depletion of the natural resources and environmental pollution's problem. Especially, for the countries which have not enough space recycling of the waste eliminating waste on regular basis or decreasing the amount and volume of waste have provided the important advantages. There are lots of studies and projects to develop both protect resources and prevent environmental pollution. PET bottles are commonly used in beverage industry and can be reused after physical and chemical recycling processes. Usage areas of recycled PET have been developed rapidly. Although recycled PET is used in plastic industry, composite industry also provides usage alternatives of recycled PET. Textile is a suitable sector for recycling of some plastics made of polymers too. In this study, the recycling technologies and applications of waste PET bottles have been investigated and scientific works in this area have been summarized.

  15. The value of PET, CT and in-line PET/CT in patients with gastrointestinal stromal tumours: long-term outcome of treatment with imatinib mesylate

    Energy Technology Data Exchange (ETDEWEB)

    Goerres, G.W.; Hany, T.F.; Schulthess, G.K. von [University Hospital Zurich, Division of Nuclear Medicine, Zurich (Switzerland); Stupp, R.; Luthi, F.; Leyvraz, S. [University of Lausanne Medical Centre, Multidisciplinary Oncology Centre, Lausanne (Switzerland); Barghouth, G.; Schnyder, P. [University of Lausanne Medical Centre, Department of Radiology, Lausanne (Switzerland); Pestalozzi, B. [University Hospital Zurich, Department of Oncology, Zurich (Switzerland); Dizendorf, E. [University Hospital Zurich, Division of Nuclear Medicine, Zurich (Switzerland); International Tomography Center, Novosibirsk (Russian Federation)

    2005-02-01

    Gastrointestinal stromal tumours (GIST) are mesenchymal neoplasms of the gastrointestinal tract that are unresponsive to standard sarcoma chemotherapy. Imaging of GIST patients is done with structural and functional methods such as contrast-enhanced helical computed tomography (ceCT) and positron emission tomography (PET) with {sup 18}F-fluorodeoxyglucose (FDG). The aim of this study was to compare the prognostic power of PET and ceCT and to evaluate the clinical role of PET/CT imaging. All patients with GIST undergoing PET or PET/CT examinations were prospectively included in this study, and the median overall survival, time to progression and treatment duration were documented. The prognostic significance of PET and ceCT criteria of treatment response was assessed and PET/CT was compared with PET and ceCT imaging. Data for 34 patients (19 male, 15 female, 21-76 years) undergoing PET or PET/CT for staging or restaging were analysed. In 28 patients, PET/CT and ceCT were available after introduction of treatment with the tyrosine kinase inhibitor imatinib mesylate (Gleevec; Novartis, Basel, Switzerland). Patients without FDG uptake after the start of treatment had a better prognosis than patients with residual activity. In contrast, ceCT criteria provided insufficient prognostic power. However, more lesions were found on ceCT images than on PET images, and FDG uptake was sometimes very variable. PET/CT delineated active lesions better than did the combination of PET and ceCT imaging. Both PET and PET/CT provide important prognostic information and have an impact on clinical decision-making in GIST patients. PET/CT precisely delineates lesions and thus allows for the correct planning of surgical interventions. (orig.)

  16. Fabrication Technologies of the High Gradient Accelerator Structures at 100MV/m Range

    CERN Document Server

    Wang, Juwen; Van Pelt, John; Yoneda, Charles; Gudkov, D; Riddone, Germana; Higo, Toshiyasu; Takatomi, Toshikazu

    2010-01-01

    A CERN-SLAC-KEK collaboration on high gradient X-band structure research has been established in order to demonstrate the feasibility of the CLIC baseline design for the main linac stably operating at more than 100 MV/m loaded accelerating gradient. Several prototype CLIC structures were successfully fabricated and high power tested. They operated at 105 MV/m with a breakdown rate that meets the CLIC linear collider specifications of <5×10-7/pulse/m. This paper summarizes the fabrication technologies including the mechanical design, precision machining, chemical cleaning, diffusion bonding as well as vacuum baking and all related assembly technologies. Also, the tolerances control, tuning and RF characterization will be discussed

  17. Chemical recycling of post-consumer PET: structural characterization of terephthalic acid and the effect of Alkaline Hydrolysis at low temperature

    International Nuclear Information System (INIS)

    Due to the environmental impact caused by PET packaging disposal, this material recycling has been thoroughly discussed and evaluated. In particular, chemical recycling enables achievement of the monomers that are used in PET resin manufacture: ethylene glycol (EG) and terephthalic acid (PTA). Therefore, studies for this process optimization are important from environmental and economic points of view. The present study investigated certain parameters that influence the depolymerization reaction of PET post-consumer via alkaline hydrolysis in order to obtain PTA. Assays were performed at 70 °C by varying the concentration of sodium hydroxide and the reaction time. The best results were obtained at 10.82 mol L-1 NaOH and 9 h reaction time. Consequently, it was possible to prove this process viability, once analyses by infrared and nuclear magnetic resonance confirmed that PTA was obtained in all reactions performed. (author)

  18. Development of Stripline Kickers for Low Emittance Rings: Application to the Beam Extraction Kicker for CLIC Damping Rings

    CERN Document Server

    AUTHOR|(SzGeCERN)728476; Toral Fernandez, Fernando

    In the framework of the design study of Future Linear Colliders, the Compact Linear Collider (CLIC) aims for electron-positron collisions with high luminosity at a nominal centre-of-mass energy of 3 TeV. To achieve the luminosity requirements, Pre-Damping Rings (PDRs) and Damping Rings (DRs) are required: they reduce the beam emittance before the beam is accelerated in the main linac. Several injection and extraction systems are needed to inject and extract the beam from the PDRs and DRs. The work of this Thesis consists of the design, fabrication and laboratory tests of the first stripline kicker prototype for beam extraction from the CLIC DRs, although the methodology proposed can be extended to stripline kickers for any low emittance ring. The excellent field homogeneity required, as well as a good transmission of the high voltage pulse through the electrodes, has been achieved by choosing a novel electrode shape. With this new geometry, it has been possible to benefit from all the advantages that the most...

  19. Tuning procedure for traveling wave structures and its application to the C-Band cavities for SPARC photo injector energy upgrade

    International Nuclear Information System (INIS)

    In this paper we illustrate the tuning procedure we implemented to tune the traveling wave structures designed and constructed for the SPARC photo-injector energy upgrade. The procedure has been derived from that proposed and adopted for the CLIC structures at CERN (J. Shi et al., Tuning of clic accelerating structure prototypes at Cern, Proc. of LINAC 2010, Tsukuba, Japan, 2010). In the first part of the paper we go through the analytical formulas also illustrating and discussing an algorithm to tune the input and output couplers. A detailed description of the measurements we have done before and after the tuning of the SPARC C-band structure prototype is then illustrated

  20. Pets as transitional objects: their role in children's emotional development.

    Science.gov (United States)

    Triebenbacher, S L

    1998-02-01

    Children's use of pets as transitional objects and the contributions of pets to children's emotional well-being were examined. The sample included 94 boys and 80 girls in preschool through Grade 5; 70% were current pet owners, and 30% were not pet owners. Each participant was individually interviewed using a structured interview format of 20 questions for current pet owners and three questions for non-pet owners to assess perceptions about the role of friendships between animals and humans, shared activities between children and pets, ways animals and humans communicate love for one another, types of verbal and nonverbal communication and interactions between animals and humans, and ways animals provide love, security, and emotional support to humans. Analysis indicated that children perceive their pets as special friends, important family members, and providers of social interactions, affection, and emotional support. Results are discussed in terms of the parallels between children's use of inanimate transitional objects and their use of pets as transitional objects. PMID:9520553

  1. Your Pet's Medications

    Science.gov (United States)

    ... by Animal/Species Browse by Topic Browse by Discipline Resources VMA Resource Center Tools for K-12 ... infection because giving the preventive to a heartworm-positive pet will not treat the infection and could ...

  2. Cold Weather Pet Safety

    Science.gov (United States)

    ... Emergency Care Animal Welfare Veterinary Careers Public Health Cold Weather Pet Safety Client Handout Available for download ... in hot cars , but did you know that cold weather also poses serious threats to your pets’ ...

  3. Combined PET/MRI

    DEFF Research Database (Denmark)

    Bailey, D. L.; Pichler, B. J.; Gückel, B.;

    2015-01-01

    This paper summarises key themes and discussions from the 4th international workshop dedicated to the advancement of the technical, scientific and clinical applications of combined positron emission tomography (PET)/magnetic resonance imaging (MRI) systems that was held in Tübingen, Germany, from...... February 23 to 27, 2015. Specifically, we summarise the three days of invited presentations from active researchers in this and associated fields augmented by round table discussions and dialogue boards with specific topics. These include the use of PET/MRI in cardiovascular disease, paediatrics, oncology......, neurology and multi-parametric imaging, the latter of which was suggested as a key promoting factor for the wider adoption of integrated PET/MRI. Discussions throughout the workshop and a poll taken on the final day demonstrated that attendees felt more strongly that PET/MRI has further advanced in both...

  4. Numerical simulation for drop impact of PET bottle considering fluid-structure interaction%考虑流固耦合作用的PET瓶跌落碰撞数值仿真

    Institute of Scientific and Technical Information of China (English)

    李强; 刘淑莲; 应光耀; 郑水英

    2012-01-01

    以聚对苯二甲酸乙二醇酯(PET)瓶为研究对象,选用Johnson-Cook本构模型构建PET材料的率相关方程,并根据率相关拉伸实验确定Johnson-Cook方程中的参数.采用Euler法描述流体方程,Lagrange法描述结构方程,应用动力学软件MSC.Dytran中基于混合的Lagrange格式和Euler格式的有限单元和有限体积技术实现流体和结构的耦合作用,完成了贮液PET瓶跌落碰撞过程的数值仿真计算.通过计算,分析PET瓶在碰撞冲击过程中力学行为和能量转化过程,得到碰掩过程中PET瓶底部接触单元不同高度的等效应力时程曲线和最大等效应力随跌落角度、贮液量和壁厚的变化关系,从而分析比较不同跌落高度、跌落角度,贮液量及PET瓶壁厚对PET瓶跌落冲击特性的影响.计算结果表明:随着跌落高度和贮液量的增大,PET瓶所受冲击应力和损伤逐渐增大;冲击应力与壁厚为非线性关系,而与跌落角度呈现强差异性.%With poly ethylene terephthalate (PET) bottle as the research object, the Johnson-Cook equation was chosen to analyze the rate-dependent mechanical properties of PET after its relationship parameters were determined through the rate-dependent tensile experiments. The Euler description was adopted for the fluid domain, and for the structure domain the Lagrange method was used. The computation of the fluid-structure interaction was realized by the method of the MSC. Dytran coupling finite element and finite volume technique based on Lagrange and Euler scheme, and the simulation of the fluid-filled PET bottle in the crash was achieved. Based on numerical calculation, the mechanical behavior and energy conversation process of the PET bottle in the impact were analyzed. The stress time-history curves of contact element at different heights, von Mises stress distribution at various drop angles and the curves for maximum von Mises stress versus liquid quantity, bottle thickness during

  5. Effects of rf breakdown on the beam in the Compact Linear Collider prototype accelerator structure

    OpenAIRE

    Palaia, Andrea; Jacewicz, Marek; Ruber, Roger; Ziemann, Volker; Farabolini, Wilfrid

    2013-01-01

    Understanding the effects of rf breakdown in high-gradient accelerator structures on the acceleratedbeam is an extremely relevant aspect in the development of the Compact Linear Collider (CLIC) andis one of the main issues addressed at the Two-beam Test Stand at the CLIC Test Facility 3 at CERN.During a rf breakdown high currents are generated causing parasitic magnetic fields that interact withthe accelerated beam affecting its orbit. The beam energy is also affected because the power is part...

  6. Cortical surface-based statistical analysis of brain PET images

    International Nuclear Information System (INIS)

    Precise and focal analysis of brain PET using voxel-based statistical mapping is limited due to the innate low spatial resolution of PET images which causes partial volume effect as well as due to the low precision of the image registration. In this study, we propose a cortical surface-based method for the precise analysis of brain PET images in combination with MRI. 18F-FDG brain PET images were acquired using GE ADVANCE PET scanner in 3D mode. 3D T1-weighted axial MR images were acquired from Philips Intera 1.5T scanner with slice thickness 1.5 mm and FOV=22 cm. The first step of analysis, we segmented gray and white matter from the structural T1 images using Freesurfer (MGH, Harvard Medical School) which extract the white matter surface using a deformable surface model. The cortical surface was further parcellated automatically into 85 anatomically relevant brain sub-regions. The second step, we developed a method for registering PET images to MRI in combination with a mutual information algorithm to maximize total metabolic activity within the gray matter band. Partial volume correction of PET image was conducted utilizing the extracted gray matter. The third step, we calculated mean cortical activity along the path from the white matter surface to the gray matter surface. The cortical activity was represented on the spatially normalized surface which statistical evaluation of cortical activity was conducted with. We evaluated the surface-based representation of PET images and the registration of PET images and the registration of PET and MRI utilizing cortical parcellation. The preliminary results showed that our method is very promising in the analysis of subtle cortical activity difference. We proposed a novel surface-based approach of brain PET analysis using high resolution MRI. Cortical Surface-based method was very efficient in the precise representation of brain activity, correction of partial volume effect as well as better spatial normalization

  7. Cortical surface-based statistical analysis of brain PET images

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hae Jeong; Kim, Jae Jin; Yoon, Mi Jin; Yoo, Young Hoon; Lee, Jong Doo [School of Medicine, Yonsei University, Seoul (Korea, Republic of)

    2004-07-01

    Precise and focal analysis of brain PET using voxel-based statistical mapping is limited due to the innate low spatial resolution of PET images which causes partial volume effect as well as due to the low precision of the image registration. In this study, we propose a cortical surface-based method for the precise analysis of brain PET images in combination with MRI. {sup 18}F-FDG brain PET images were acquired using GE ADVANCE PET scanner in 3D mode. 3D T1-weighted axial MR images were acquired from Philips Intera 1.5T scanner with slice thickness 1.5 mm and FOV=22 cm. The first step of analysis, we segmented gray and white matter from the structural T1 images using Freesurfer (MGH, Harvard Medical School) which extract the white matter surface using a deformable surface model. The cortical surface was further parcellated automatically into 85 anatomically relevant brain sub-regions. The second step, we developed a method for registering PET images to MRI in combination with a mutual information algorithm to maximize total metabolic activity within the gray matter band. Partial volume correction of PET image was conducted utilizing the extracted gray matter. The third step, we calculated mean cortical activity along the path from the white matter surface to the gray matter surface. The cortical activity was represented on the spatially normalized surface which statistical evaluation of cortical activity was conducted with. We evaluated the surface-based representation of PET images and the registration of PET images and the registration of PET and MRI utilizing cortical parcellation. The preliminary results showed that our method is very promising in the analysis of subtle cortical activity difference. We proposed a novel surface-based approach of brain PET analysis using high resolution MRI. Cortical Surface-based method was very efficient in the precise representation of brain activity, correction of partial volume effect as well as better spatial normalization.

  8. Positron kinetics in an idealized PET environment

    Science.gov (United States)

    Robson, R. E.; Brunger, M. J.; Buckman, S. J.; Garcia, G.; Petrović, Z. Lj.; White, R. D.

    2015-08-01

    The kinetic theory of non-relativistic positrons in an idealized positron emission tomography PET environment is developed by solving the Boltzmann equation, allowing for coherent and incoherent elastic, inelastic, ionizing and annihilating collisions through positronium formation. An analytic expression is obtained for the positronium formation rate, as a function of distance from a spherical source, in terms of the solutions of the general kinetic eigenvalue problem. Numerical estimates of the positron range - a fundamental limitation on the accuracy of PET, are given for positrons in a model of liquid water, a surrogate for human tissue. Comparisons are made with the ‘gas-phase’ assumption used in current models in which coherent scattering is suppressed. Our results show that this assumption leads to an error of the order of a factor of approximately 2, emphasizing the need to accurately account for the structure of the medium in PET simulations.

  9. Usefulness of PET in non-lesional temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Objective. To evaluate the usefulness of PET in patients with refractory non-lesional temporal lobe epilepsy. Material and methods. We present three patients with features of temporal lobe epilepsy refractory to medication, where high definition MRI was normal. Results. These patients had PET hypometabolism in the temporal areas related to clinical and neurophysiological findings. Two of these patients were implanted with subdural grids to confirm the diagnosis and the third was operated directly based on the findings of PET. Encourage the presentation of the importance in recent years is acquiring the PET. Conclusion. In those patients in clinical neurophysiology and epilepsy with suspected temporal lobe, but in the MRI images show no structural lesions, PET can play an important role defining the diagnosis. (authors)

  10. Analytical considerations for linear and nonlinear optimization of the TME cells. Application to the CLIC pre-damping rings

    CERN Document Server

    Fanouria, Antoniou

    2014-01-01

    The theoretical minimum emittance cells are the optimal configurations for achieving the absolute minimum emittance, if specific optics constraints are satisfied at the middle of the cell's dipole. Linear lattice design options based on an analytical approach for the theoretical minimum emittance cells are presented in this paper. In particular the parametrization of the quadrupole strengths and optics functions with respect to the emittance and drift lengths is derived. A multi-parametric space can be then created with all the cell parameters, from which one can chose any of them to be optimized. An application of this approach are finally presented for the linear and non-linear optimization of the CLIC Pre-damping rings.

  11. PET and PET/CT in neuroendocrine tumours

    International Nuclear Information System (INIS)

    In the paper three modes of PET diagnostics are analyzed. Fluoro-deoxy-glucose (FDG)18F is recommended for evaluation of the most solid tumours. 18F DOPA PET with an aromatic aminoacid radiotracer is promising for studying neuroendocrine tumours (NET). Successes of PET of somatostatin receptors (SS-RPET) recently reported were mainly connected with high diagnostic accuracy achieved in NET tumours

  12. Clinical Application of 18F-FDG PET in Epilepsy

    International Nuclear Information System (INIS)

    FDG PET has been used as a diagnostic tool for localization of seizure focus for last 2-3 decades. In this article, the clinical usefulness of FDG PET in the management of patients with epilepsy has been reviewed, which provided the evidences to justify the medicare reimbursement for FDG PET in management of patients with epilepsy. Literature review demonstrated that FDG PET provides an important information in localization of seizure focus and determination whether a patients is a surgical candidate or not. FDG PET has been reported to have high diagnostic performance in localization of seizure focus in neocortical epilepsy as well as temporal lobe epilepsy regardless of the presence of structural lesion on MRI. Particularly, FDG PET can provide the additional information when the results from standard diagnositic modality such as interictal or video-monitored EEG, and MRI are inconclusive or discordant, and make to avoid invasive study. Furthermore, the presence of hypometabolism and extent of metabolic extent has been reported as an important predictor for seizure free outcome. However, studies suggested that more accurate localization and better surgical outcome could be expected with multimodal approach by combination of EEG, MRI, and functional studies using FDG PET or perfusion SPECT rather than using a single diagnostic modality in management of patients with epilepsy. Complementary use of FDG PET in management of epilepsy is worth for good surgical outcome in epilepsy patients

  13. Virtual hybrid bronchoscopy using PET/CT data sets

    Science.gov (United States)

    Englmeier, Karl-Hans; Seemann, Marcus D.

    2007-03-01

    The aim of this study was to demonstrate the possibilities, advantages and limitations of virtual bronchoscopy using data sets from positron emission tomography (PET) and computed tomography (CT). Eight consecutive patients with lung cancer underwent PET/CT. PET was performed with F-18-labelled 2-[fluorine-18]-fluoro-2-deoxy-D: -glucose ((18)F-FDG). The tracheobronchial system was segmented with a volume-growing algorithm, using the CT data sets, and visualized with a shaded-surface rendering method. The primary tumours and the lymph node metastases were segmented for virtual CT-bronchoscopy using the CT data set and for virtual PET/CT-bronchoscopy using the PET/CT data set. Virtual CT-bronchoscopy using the low-dose or diagnostic CT facilitates the detection of anatomical/morphological structure changes of the tracheobronchial system. Virtual PET/CT-bronchoscopy was superior to virtual CT-bronchoscopy in the detection of lymph node metastases (P=0.001), because it uses the CT information and the molecular/metabolic information from PET. Virtual PET/CT-bronchoscopy with a transparent colour-coded shaded-surface rendering model is expected to improve the diagnostic accuracy of identification and characterization of malignancies, assessment of tumour staging, differentiation of viable tumour tissue from atelectases and scars, verification of infections, evaluation of therapeutic response and detection of an early stage of recurrence that is not detectable or is misjudged in comparison with virtual CT-bronchoscopy.

  14. Alignement général du CLIC: stratégie et progrès

    CERN Document Server

    Mainaud-Durand, H

    2008-01-01

    La faisabilité concernant le pré-alignement actif du CLIC sera démontrée si l?on peut prouver qu?il existe une référence et ses capteurs associés permettant l?alignement des composants à mieux que 3 microns (1?). Pour répondre à ce challenge, une méthode de mesure d?écarts à un fil tendu est proposée, basée sur 40 ans de pratique de cette technique au CERN. Quelques problèmes demeurent concernant cette méthode : la connaissance de la forme du fil tendu utilisé comme référence droite, la détermination du géoïde à la précision souhaitée et le développement de capteurs bas coût permettant des mesures sub-micrométriques. Des études ont été entreprises afin de lever les derniers points en suspens, pendant que cette solution est intégrée dans une proposition concernant l?alignement général du CLIC. Cela implique un grand nombre d?interactions au niveau du projet, dans des domaines aussi différents que le génie civil, l?intégration, la physique du faisceau, la métrologie des �...

  15. Medical application of PET technology

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sang Moo; Choi, C. W.; An, S. H.; Woo, K. S.; Chung, W. S.; Yang, S. D.; Jun, G. S. and others

    1999-04-01

    We performed following studies using PET technology: 1. Clinical usefulness of [{sup 18}F]FDG whole body PET in malignant disease 2. Clinical usefulness of quantitative evaluation of F-18-FDG 3. Pilot study of C-11 methionine PET in brain tumor 4. PET study in patients with Parkinson's disease 5. A study on the clinical myocardial PET image. PET gives various metabolic information for the living human body, and is very important, new diagnostic modality. The PET study will give us the information of cancer patients such as early detection of cancer, staging, recurrence detection and characterization of cancer. The quantitative analysis using PET could be applied to evaluate the pathophysiology of various diseases and develop new drugs and develop new radiopharmaceuticals.

  16. Medical application of PET technology

    International Nuclear Information System (INIS)

    We performed following studies using PET technology: 1. Clinical usefulness of [18F]FDG whole body PET in malignant disease 2. Clinical usefulness of quantitative evaluation of F-18-FDG 3. Pilot study of C-11 methionine PET in brain tumor 4. PET study in patients with Parkinson's disease 5. A study on the clinical myocardial PET image. PET gives various metabolic information for the living human body, and is very important, new diagnostic modality. The PET study will give us the information of cancer patients such as early detection of cancer, staging, recurrence detection and characterization of cancer. The quantitative analysis using PET could be applied to evaluate the pathophysiology of various diseases and develop new drugs and develop new radiopharmaceuticals

  17. Role of PET in Lymphoma

    OpenAIRE

    Markus Schwaiger; Hinrich Wieder

    2005-01-01

    In Hodgkin's lymphoma (HL), PET imaging should be performed in all patients, particularlyin stage I or II disease where change in staging will alter management. For aggressiveNon-Hodgkin's lymphoma (NHL), PET imaging is valuable to provide a baseline forresponse evaluation. For indolent NHL, it is concluded that PET imaging is not generallyindicated. For HL, a negative FDG-PET scan is highly indicative of long-term, disease-freesurvival and is particularly useful in the presence of residual C...

  18. PET imaging of inflammation

    International Nuclear Information System (INIS)

    Inflammatory diseases are common place and often chronic. Most inflammatory cells have increased uptake of glucose which is enhanced in the presence of local cytokines. Therefore, imaging glucose metabolism by the means of 18F-fluoro-deoxy-glucose (FDG) positron emission tomography (PET) holds significant promise in imaging focal inflammation. Most of the work published involved small series of patients with either vasculitis, sarcoid or rheumatoid arthritis. It would appear that FDG PET is a simple and effective technique to identify inflammatory tissue in these conditions. There is even some work to suggest that by comparing baseline and early post therapy scans clinical outcome can be predicted. This would appear to be true with vasculitis as well as retroperitoneal fibrosis. The number of patients in each study is small but the evidence is compelling enough to recommend FDG PET imaging in the routine care of these patients.

  19. Novel PET sensors

    International Nuclear Information System (INIS)

    This thesis describes the design, synthesis and evaluation of novel molecular sensors that utilize the phenomena of Photoinduced Electron Transfer (PET). PET design can be incorporated into molecules to allow them to selectively bind certain guest molecules. PET works by the modulation of electron potentials within a molecule. Binding events between a host and guest can, if designed suitably, change these potentials enough to cause a transfer of electronic charge within the molecular sensor. This event can be accurately and sensitively monitored by the use of ultra violet or fluorescence spectroscopy. A sensor molecule can be constructed by matching the guest to a suitable receptor site and incorporating this into a molecule containing a fluorophore with the correct electron potential characteristics. By using existing synthetic routes as well as exploiting new pathways these sensor molecules C n be constructed to contain a fluorophore separated from a guest receptor(s) by suitable spacers units. When put together these facets go to creating molecules that by design are sensitive and selective for certain guest molecules or functional groups. This methodology allows the synthetic chemist to rationally design and synthesise PET sensors, tailored to the needs of the guest. In this thesis the synthesis and evaluation of a novel PET sensors for D-glucosamine, disaccharides and fluoride is presented. It is believed that the novel sensors using the PET phenomenon presented in this thesis are a worthwhile extension of previous works undertaken by other groups around the world and shows new pathways to increasingly complex and sophisticated sensor molecular design. (author)

  20. Design of the 15 GHz BPM test bench for the CLIC test facility to perform precise stretched-wire RF measurements

    Science.gov (United States)

    Zorzetti, Silvia; Fanucci, Luca; Galindo Muñoz, Natalia; Wendt, Manfred

    2015-09-01

    The Compact Linear Collider (CLIC) requires a low emittance beam transport and preservation, thus a precise control of the beam orbit along up to 50 km of the accelerator components in the sub-μm regime is required. Within the PACMAN3 (Particle Accelerator Components Metrology and Alignment to the Nanometer Scale) PhD training action a study with the objective of pre-aligning the electrical centre of a 15 GHz cavity beam position monitor (BPM) to the magnetic centre of the main beam quadrupole is initiated. Of particular importance is the design of a specific test bench to study the stretched-wire setup for the CLIC Test Facility (CTF3) BPM, focusing on the aspects of microwave signal excitation, transmission and impedance-matching, as well as the mechanical setup and reproducibility of the measurement method.

  1. Design of the 15 GHz BPM test bench for the CLIC test facility to perform precise stretched-wire RF measurements

    International Nuclear Information System (INIS)

    The Compact Linear Collider (CLIC) requires a low emittance beam transport and preservation, thus a precise control of the beam orbit along up to 50 km of the accelerator components in the sub-μm regime is required. Within the PACMAN3 (Particle Accelerator Components Metrology and Alignment to the Nanometer Scale) PhD training action a study with the objective of pre-aligning the electrical centre of a 15 GHz cavity beam position monitor (BPM) to the magnetic centre of the main beam quadrupole is initiated. Of particular importance is the design of a specific test bench to study the stretched-wire setup for the CLIC Test Facility (CTF3) BPM, focusing on the aspects of microwave signal excitation, transmission and impedance-matching, as well as the mechanical setup and reproducibility of the measurement method. (paper)

  2. Alignment Methods Developed for the Validation of the Thermal and Mechanical Behaviour of the Two Beam Test Modules for the CLIC Project

    CERN Document Server

    Mainaud Durand, Helene; Sosin, Mateusz; Rude, Vivien

    2014-01-01

    CLIC project will consist of more than 20 000 two meters long modules. A test setup made of three modules is being built at CERN to validate the assembly and integration of all components and technical systems and to validate the short range strategy of pre-alignment. The test setup has been installed in a room equipped with a sophisticated system of ventilation able to reproduce the environmental conditions of the CLIC tunnel. Some of the components have been equipped with electrical heaters to simulate the power dissipation, combined with a water cooling system integrated in the RF components. Using these installations, to have a better understanding of the thermal and mechanical behaviour of a module under different operation modes, machine cycles have been simulated; the misalignment of the components and their supports has been observed. This paper describes the measurements methods developed for such a project and the results obtained.

  3. PET-CT; PET-CT

    Energy Technology Data Exchange (ETDEWEB)

    Schober, O. [Univeritaetsklinikum Muenster (Germany). Klinik und Poliklinik fuer Nuklearmedizin; Heindel, W. [Univeritaetsklinikum Muenster (Germany). Inst. fuer Klinische Radiologie

    2008-07-01

    Positron emission tomography - computerized tomography (PET-CT) is the fusion of two modern imaging techniques. The book includes the following chapters: 1. fundamentals: radiation protection aspects, radionuclide production, contrast agents, patient preparation, image interpretation; 2. diagnostics of carcinomas: carcinomas in brain, head-throat, thyroid, lungs, intestinal tract, gynecological carcinomas, urinary tract and bladder carcinomas, prostate carcinomas, malignant lymphomas, malignant malinomas, carcinomas in the skeletal system; 3. infections; 4. diagnostics of cardiovascular diseases; 5. diagnostics of neurodegenerative diseases; 6. developments and perspectives, 7. attachments: internet links, glossary, abbreviations.

  4. Side-by-side reading of PET and CT scans in oncology: Which patients might profit from integrated PET/CT?

    International Nuclear Information System (INIS)

    Most early publications on integrated positron emission tomography/computed tomography (PET/CT) devices have reported the new scanner generation to be superior to conventional PET. However, few of these studies have analysed the situation where, in addition to PET, a current CT scan is available for side-by-side viewing. This fact is important, because combined PET/CT or a software-based fusion of the two modalities may improve diagnosis only in cases where side-by-side reading of PET and CT data does not lead to a definitive diagnosis. The aim of this study was to analyse which patients will profit from integrated PET/CT in terms of lesion characterization. A total of 328 consecutively admitted patients referred for PET in whom a current CT scan was available were included in the study. The localization of all pathological PET lesions, as well as possible infiltration of adjacent anatomical structures, was assessed. Of 467 pathological lesions, 94.0% were correctly assessed with respect to localization and infiltration by either conventional PET alone (51.6%) or combined reading of PET and the already existing CT scans (42.4%). Hence, in only 6.0% of all lesions, affecting 6.7% of all patients, could evaluation have profited from integrated PET/CT. We conclude that side-by-side viewing of PET and CT scans is essential, as in 42.4% of all cases, combined viewing was important for a correct diagnosis in our series. In up to 6.7% of patients, integrated PET/CT might have given additional information, so that in nearly 50% of patients some form of combined viewing of PET and CT data is needed for accurate lesion characterization. (orig.)

  5. PET imaging of hypoxia

    International Nuclear Information System (INIS)

    Hypoxia in tumors has been related to poor response to conventional therapies. This paper will discuss the methods, both invasive and non-invasive, used to determine hypoxia levels within tumors. PET imaging with two lead compounds 18F-fluoro misonidazole (18FMISO) and Cu-(II)-diacetyl-bis(N4-methylthiosemicarbazone (Cu-ATSM) and their relative effectiveness in delineating hypoxic regions will be discussed. The advantages of Cu-ATSM-PET over existing imaging agents will be discussed along with its potential application as a direct-and/or surrogate marker for the determination of oncological hypoxia in vivo

  6. Value of PET and PET-CT in the management of lymphoma

    International Nuclear Information System (INIS)

    ) and extra-nodal (especially spleen and bone involvement) disease, but PET negative, CT positive lesions do occur in a small number of cases. High FDG uptake in brown fat tissue or muscle can hamper the interpretation of the head and neck and mediastinal region and physiological uptake in the brain, myocardium and renal collecting system can obscure lymphoma evaluation in those sites. Therefore, FDG-PET should not be used in stead, but in combination with CT. Especially the use of combined PET-CT machines can improve the accuracy by increasing the certainty of diagnosis in those difficult regions.. Improved lesion detection and characterization led to a modification of disease stage and subsequent management in only a limited number of patients and the impact on outcome remains unknown. The most important reason to perform a baseline PET scan is to facilitate the evaluation of residual disease after therapy, currently the most established indication for PET in lymphoma. At the end of treatment, lymphoma patients often present with a residual mass but only a minority of them will eventually relapse. Structural imaging can not reliably discriminate fibrotic from viable tumor masses. Early identification of patients who have not been cured by their primary treatment is however important since better outcome after further treatment can be expected when such patients are treated at an earlier stage with lower tumour burden. Numerous studies have shown the effectiveness of FDG-PET in the detection of residual disease at the end of therapy. In a recent systematic review [2] including 15 studies (350 NHL and 408 HD), the pooled sensitivity and specificity for detection of residual disease in HD were 84% and 90%, where for NHL this was 72% and 100%. A negative PET at the end of treatment clearly identifies patients with an excellent prognosis. Relapses are infrequent and occur rarely within the first year after the end of treatment probably reflecting minimal tumor burden below

  7. Measurement of Higgs couplings and mass in e+e- collisions at CLIC in the sqrt(s) range of 350 GeV - 3 TeV

    Czech Academy of Sciences Publication Activity Database

    Laštovička, Tomáš

    Trieste: S I S S A, 2013, s. 1-7, 295. ISSN 1824-8039. [EPS-HEP 2013 - The European Physical Society Conference on High Energy Physics 2013. Stockholm (SE), 17.07.2013- 24.07.2013] Institutional support: RVO:68378271 Keywords : Higgs boson * CLIC * CERN * Higgs branching ratios * Higgs mass * linear accelerator Subject RIV: BF - Elementary Particles and High Energy Physics http://pos.sissa.it/archive/conferences/180/295/EPS-HEP%202013_295.pdf

  8. Simultaneous PET and MR imaging

    International Nuclear Information System (INIS)

    We have developed a prototype PET detector which is compatible with a clinical MRI system to provide simultaneous PET and MR imaging. This single-slice PET system consists of 48 2x2x10mm3 LSO crystals in a 38 mm diameter ring configuration that can be placed inside the receiver coil of the MRI system, coupled to three multi-channel photomultipliers housed outside the main magnetic field via 4 m long and 2 mm diameter optical fibres. The PET system exhibits 2 mm spatial resolution, 41% energy resolution at 511 keV and 20 ns timing resolution. Simultaneous PET and MR phantom images were successfully acquired. (author)

  9. Preparation of PET/Ag hybrid fibers via a biomimetic surface functionalization method

    International Nuclear Information System (INIS)

    Highlights: ► PET/Ag fibers were prepared via a biomimetic surface functionalization method. ► The method is fast, simple, efficient, nontoxic, as well as controllable. ► The silver layer coated on PET-PDA fibers was continuous, uniform, and compact. ► The as-prepared PET-Ag fibers possess good electrical conductivity. ► The binding force between the silver layer and PET-PDA fiber was strong. - Abstract: A biomimetic method for the preparation of highly conductive silver-plated polyethylene terephthalate (PET) fiber was demonstrated. First, the PET fibers were functionalized with a bio-inspired polydopamine (PDA) coating, simply by being dispersed in a dopamine solution under mild stirring at room temperature. Electroless plating of silver was then carried out on the surface of the PET-PDA fiber. An aqueous solution of silver nitrate and glucose was used as silver precursor and reducing reagent, respectively. The overall procedure is fast, simple, efficient, nontoxic, as well as controllable. The PDA layer on the PET surface was characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, and contact angle measurement. The crystalline structure of the modified PET fiber was studied by X-ray diffraction (XRD). The morphology of the PET-PDA and the PET-Ag fiber was observed by scanning electron microscopy (SEM). SEM results showed that the silver layer coated on PET-PDA was continuous, uniform, and compact. The as-prepared PET-Ag fibers have good electrical conductivity, with surface resistivity as low as 0.4 mΩ cm. The binding force between the silver layer and PET-PDA fiber was strong enough that the silver layer remained compact and continuous after the PET-PDA/Ag fiber was rinsed under ultrasound for 4 h.

  10. Analysis of the Metabolic and Structural Brain Changes in Patients With Torture-Related Post-Traumatic Stress Disorder (TR-PTSD) Using 18F-FDG PET and MRI.

    Science.gov (United States)

    Zandieh, Shahin; Bernt, Reinhard; Knoll, Peter; Wenzel, Thomas; Hittmair, Karl; Haller, Joerg; Hergan, Klaus; Mirzaei, Siroos

    2016-04-01

    Many people exposed to torture later suffer from torture-related post-traumatic stress disorder (TR-PTSD). The aim of this study was to analyze the morphologic and functional brain changes in patients with TR-PTSD using magnetic resonance imaging (MRI) and positron emission tomography (PET).This study evaluated 19 subjects. Thirteen subcortical brain structures were evaluated using FSL software. On the T1-weighted images, normalized brain volumes were measured using SIENAX software. The study compared the volume of the brain and 13 subcortical structures in 9 patients suffering from TR-PTSD after torture and 10 healthy volunteers (HV). Diffusion-weighted imaging (DWI) was performed in the transverse plane. In addition, the 18F-FDG PET data were evaluated to identify the activity of the elected regions.The mean left hippocampal volume for the TR-PTSD group was significantly lower than in the HV group (post hoc test (Bonferroni) P < 0.001). There was a significant difference between the gray matter volume of the patients with TR-PTSD and the HV group (post hoc test (Bonferroni) P < 0.001). The TR-PTSD group showed low significant expansion of the ventricles in contrast to the HV group (post hoc test (Bonferroni) P < 0.001). Diffusion-weighted imaging revealed significant differences in the right frontal lobe and the left occipital lobe between the TR-PTSD and HV group (post hoc test (Bonferroni) P < 0.001).Moderate hypometabolism was noted in the occipital lobe in 6 of the 9 patients with TR-PTSD, in the temporal lobe in 1 of the 9 patients, and in the caudate nucleus in 5 of the 9 patients. In 2 cases, additional hypometabolism was observed in the posterior cingulate cortex and in the parietal and frontal lobes.The findings from this study show that TR-PTSD might have a deleterious influence on a set of specific brain structures. This study also demonstrated that PET combined with MRI is sensitive in detecting possible metabolic and structural brain

  11. Healthy Pets and People

    Science.gov (United States)

    ... food and treats might include dry dog or cat food, dog biscuits, pig ears, beef hooves, and rodents ... after your pet, and before eating or preparing foods. Make sure to remove your ... contain dog or cat feces to prevent the spread of roundworms and ...

  12. Choosing a Pet

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    THE capital boasts countless markets of all kinds,but some of its insect,bird and pet markets immortalize Beijing culture and folkloric traditions.Don’t miss it! The Huasheng Tianqiao Market,south of the famous Panjiayuan Antique Market, was moved a few years ago and rebuilt in the

  13. PET Bottles Recycling

    Czech Academy of Sciences Publication Activity Database

    Veselý, Václav; Hanika, Jiří

    Praha : Ministry of Industry and Trade CR, 2008, s. 1-6. ISBN N. [Pollutec 2008. Lyon (FR), 02.12.2008-05.12.2008] R&D Projects: GA MPO FI-IM4/096 Institutional research plan: CEZ:AV0Z40720504 Keywords : pet recycling * waste * technical appliances Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  14. Total PET Recycling

    Czech Academy of Sciences Publication Activity Database

    Veselý, Václav; Punčochář, Miroslav

    Bratislava : Slovak University of Technology, 2004 - (Markoš, J.; Štefuca, V.), s. 222 ISBN 80-227-2052-6. [International Conference of Slovak Society of Chemical Engineering /31./. Tatranské Matliare (SK), 24.05.2004-28.05.2004] Institutional research plan: CEZ:AV0Z4072921 Keywords : recycling * waste management * pet Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  15. PET CT and lymphomas

    International Nuclear Information System (INIS)

    This presentation is about Tc and lymphomas. Classification and clinical cases of various cancer such as gastro duodenal or ulcer, mama, medullary, lymph and neck, leukemia, nodular sclerosis. Metabolic information, anatomical nature of lymphoma and its clinical presentation determine the extent that PET should be used in the patient.

  16. PET's indsats under lup

    DEFF Research Database (Denmark)

    Hansen, Peer Henrik

    2006-01-01

    En undersøgelseskommission nedsat i 1999. Fem medlemmer skal undersøge PET's efterretningsvirksomhed i forhold til politiske partier, faglige konflikter og politisk ideologiske bevægelser i Danmark under den kolde krig. Kommissionens rapport forventes færdig næste år. Udgivelsesdato: 2. juli 2006...

  17. PET and PET/CT in malignant melanoma; PET y PET/CT en melanoma maligno

    Energy Technology Data Exchange (ETDEWEB)

    Garcia O, J.R. [Nuclear Medicine and Molecular Imaging PET/CT, Centro Medico ABC, Mexico D.F. (Mexico)

    2007-07-01

    The advantages that it has the PET/CT are: 1. It diminishes mainly positive false lesions. It identifies physiologic accumulate places. 2. It diminishes in smaller grade false negative. Small injuries. Injuries with low grade concentration. Injure on intense activity areas. 3. Precise anatomical localization of accumulate places. 4. Reduction of the acquisition time. (Author)

  18. I Love Petting Zoos!

    Centers for Disease Control (CDC) Podcasts

    2010-03-23

    This Kidtastics podcast helps children learn about how to stay safe and healthy when visiting petting zoos and other animal exhibits.  Created: 3/23/2010 by Centers for Disease Control and Prevention (CDC).   Date Released: 3/23/2010.

  19. Methods of testing PET regenerates properties

    OpenAIRE

    2008-01-01

    The work presents an overview of the methods of testing poly(ethylene-terephthalate) (PET) regenerates: PET flakes, PET regranulates, PET preforms and PET bottles. All the methods have been included that are implemented for the quality testing of the mentioned products and allow constant control over the production process.

  20. Foreign body reaction associated with PET and PET/chitosan electrospun nanofibrous abdominal meshes.

    Directory of Open Access Journals (Sweden)

    Beatriz Veleirinho

    Full Text Available Electrospun materials have been widely explored for biomedical applications because of their advantageous characteristics, i.e., tridimensional nanofibrous structure with high surface-to-volume ratio, high porosity, and pore interconnectivity. Furthermore, considering the similarities between the nanofiber networks and the extracellular matrix (ECM, as well as the accepted role of changes in ECM for hernia repair, electrospun polymer fiber assemblies have emerged as potential materials for incisional hernia repair. In this work, we describe the application of electrospun non-absorbable mats based on poly(ethylene terephthalate (PET in the repair of abdominal defects, comparing the performance of these meshes with that of a commercial polypropylene mesh and a multifilament PET mesh. PET and PET/chitosan electrospun meshes revealed good performance during incisional hernia surgery, post-operative period, and no evidence of intestinal adhesion was found. The electrospun meshes were flexible with high suture retention, showing tensile strengths of 3 MPa and breaking strains of 8-33%. Nevertheless, a significant foreign body reaction (FBR was observed in animals treated with the nanofibrous materials. Animals implanted with PET and PET/chitosan electrospun meshes (fiber diameter of 0.71 ± 0.28 µm and 3.01 ± 0.72 µm, respectively showed, respectively, foreign body granuloma formation, averaging 4.2-fold and 7.4-fold greater than the control commercial mesh group (Marlex. Many foreign body giant cells (FBGC involving nanofiber pieces were also found in the PET and PET/chitosan groups (11.9 and 19.3 times more FBGC than control, respectively. In contrast, no important FBR was observed for PET microfibers (fiber diameter = 18.9 ± 0.21 µm. Therefore, we suggest that the reduced dimension and the high surface-to-volume ratio of the electrospun fibers caused the FBR reaction, pointing out the need for further studies to elucidate the mechanisms

  1. The Effect of Patient Age on Standardized Uptake Value-Hounsfield Unit Values of Male Genitourinery Structures In F-18 FDG PET/CT

    Directory of Open Access Journals (Sweden)

    Berrin Çavuşoğlu

    2011-12-01

    Full Text Available Objective: Relation between patient age and Hounsfield Unit (HU,which is the linear attenuation coefficient, and Standardized Uptake Values (SUV which is the amount of 18F-fluorodeoxyglucose (F-18 FDG uptake, measured in the areas of interest drawn to prostate, seminal vesicles and testicles in F-18 FDG Positron Emission Tomography/Computed Tomography (PET/CT images was investigated. Material and Methods: Mean and maximum SUV and HU values were recorded from the areas of interest (min 12 mm in diameter which showed FDG uptake in prostate, seminal vesicles and testicles from F-18 FDG PET-CT images of 21 male patients under 40 years without genitourinary cancer. The effect of patient age to SUV and HU values was examined with Pearson correlation test using SPSS program. Results: There was a negative insignificant correlation between patient age and SUV and HU values for prostate. For seminal vesicles, correlation between patient age and SUV values and HUmax were positive but insignificant, while correlation with HUmean was significant (r=0.459, p=0.00. Correlation between patient age and SUVmax and SUVmean values were significant for testicles (r=0.506, p=0.002 and r=0.467, p=0.005, respectively but the correlation between patient age and HUmax and HUmean values was not significant. Conclusion: F-18 FDG uptake in testicles in males increases with age until 40, suggesting an increase in metabolic rate. The significant correlation between age and mean HU values is probably caused by thickening of the tissue without an increase in glucose metabolism in seminal vesicles. In prostate, the effect of patient age to SUV and HU values was not observed until the age 40. (MIRT 2011;20:104-107

  2. PET in lung cancer staging

    International Nuclear Information System (INIS)

    The primary clinical application of FDG-PET is in the evaluation of patients with lung cancer and includes diagnosis, staging and restaging of non-small cell lung cancer. PET has a very high accuracy (sensitivity=97%, specificity=78%) for characterizing nodules that are indeterminate by chest radiograph and computed tomography. The major utility of PET in the evaluation of patients with lung cancer is the staging of the entire body. PET is more accurate than the conventional imaging modalities of CT and bone scans in the detection of metastatic disease. PET is accurate in the staging of the mediastinum, adrenal glands, and the skeletal system. PET is not as accurate in the detection of brain metastases because of their small size and the normal cortical accumulation

  3. Are Pets Good For Us?

    Institute of Scientific and Technical Information of China (English)

    邢连香

    2006-01-01

    A pet animal keeps us feel happy.Pets can staywith us when we are left by ourselves,and pets in-vite us to love and be loved.Often a cat or dog cankeep us easy at time when human words don’t help.Pets also keep us get close to the more natural animalworld.Learning to care for a pet helps a child to growup into a loving man or woman who feels responsible(有责任的) towards those dependent (依靠) on him.A pet dog can make us believe in others for we cansee faithfulness (忠诚) in the dog.In fact,we keeppets not only fo...

  4. PET/MR in oncology

    DEFF Research Database (Denmark)

    Balyasnikova, Svetlana; Löfgren, Johan; de Nijs, Robin;

    2012-01-01

    a number of different MRI techniques, such as DWI-MR (diffusion weighted imaging MR), DCE-MR (dynamic contrast enhanced MR), MRS (MR spectroscopy) and MR for attenuation correction of PET. All MR techniques presented in this paper have shown promising results in the treatment of patients with solid......After more than 20 years of research, a fully integrated PET/MR scanner was launched in 2010 enabling simultaneous acquisition of PET and MR imaging. Currently, no clinical indication for combined PET/MR has been established, however the expectations are high. In this paper we will discuss some of...... the challenges inherent in this new technology, but focus on potential applications for simultaneous PET/MR in the field of oncology. Methods and tracers for use with the PET technology will be familiar to most readers of this journal; thus this paper aims to provide a short and basic introduction to...

  5. Cyclotron/PET project in Uruguay

    International Nuclear Information System (INIS)

    The Positron Computed Tomography (PET) is a tri dimensional image technique which shows biochemical information. PET is used in neurology and cardiology diseases. The National Center Cyclotron PET has been found to research, development and health science applications.

  6. PET studies in dementia

    Energy Technology Data Exchange (ETDEWEB)

    Herholz, K. [Neurologische Universitaetsklinik and Max-Planck-Inst. fuer neurologische Forschung, Koeln (Germany)

    2003-04-01

    Measurement of local cerebral glucose metabolism (lCMRGlc) by positron emission tomography (PET) and {sup 18}F-2-fluoro-2-deoxy-D-glucose (FDG) has become a standard technique during the past 20 years and is now available at many university hospitals in all highly developed countries. Many studies have documented a close relation between lCMRGlc and localized cognitive functions, such as language and visuoconstructive abilities. Alzheimer's disease (AD) is characterized by regional impairment of cerebral glucose metabolism in neocortical association areas (posterior cingulate, temporoparietal and frontal multimodal association cortex), whereas primary visual and sensorimotor cortex, basal ganglia, and cerebellum are relatively well preserved. In a multicenter study comprising 10 PET centers (Network for Efficiency and Standardization of Dementia Diagnosis, NEST-DD) that employed an automated voxel-based analysis of FDG PET images, the distinction between controls and AD patients was 93% sensitive and 93% specific, and even in very mild dementia (at Mini Mental Status Examination (MMSE) 24 or higher) sensitivity was still 84% at 93% specificity. Significantly abnormal metabolism in mild cognitive deficit (MCI) indicates a high risk to develop dementia within the next two years. Reduced neocortical glucose metabolism can probably be detected with FDG PET in AD on average one year before onset of subjective cognitive impairment. In addition to glucose metabolism, specific tracers for dopamine synthesis ({sup 18}F-F-DOPA) and for ({sup 11}C-MP4A) are of interest for differentiation among dementia subtypes. Cortical acetylcholine esterase activity (AChE) activity is significantly lower in patients with AD or with dementia with Lewy bodies (DLB) than in age-matched normal controls. In LBD there is also impairment of dopamine synthesis, similar to Parkinson disease. (author) 115 refs.

  7. PET: active lymphoma?

    International Nuclear Information System (INIS)

    In the presented case, the PET (Positron Emission Tomography) has expired with several rolls. Firstly, it has been capable of detecting so much the infra-diaphragmatic illness not suspected after the initial treatment, as the persistence of illness in mediastinum. Later, it was helpful to face on the best place of biopsy in the mediastinum and to evaluate the situation of the patient after the treatment chemotherapeutic and the bone marrow transplantation

  8. Usage of Recycled Pet

    OpenAIRE

    A. Ebru Tayyar; Sevcan Üstün

    2010-01-01

    The increasing industrialization, urbanization and the technological development have caused to increase depletion of the natural resources and environmental pollution's problem. Especially, for the countries which have not enough space recycling of the waste eliminating waste on regular basis or decreasing the amount and volume of waste have provided the important advantages. There are lots of studies and projects to develop both protect resources and prevent environmental pollution. PET bot...

  9. PET studies in dementia

    International Nuclear Information System (INIS)

    Measurement of local cerebral glucose metabolism (lCMRGlc) by positron emission tomography (PET) and 18F-2-fluoro-2-deoxy-D-glucose (FDG) has become a standard technique during the past 20 years and is now available at many university hospitals in all highly developed countries. Many studies have documented a close relation between lCMRGlc and localized cognitive functions, such as language and visuoconstructive abilities. Alzheimer's disease (AD) is characterized by regional impairment of cerebral glucose metabolism in neocortical association areas (posterior cingulate, temporoparietal and frontal multimodal association cortex), whereas primary visual and sensorimotor cortex, basal ganglia, and cerebellum are relatively well preserved. In a multicenter study comprising 10 PET centers (Network for Efficiency and Standardization of Dementia Diagnosis, NEST-DD) that employed an automated voxel-based analysis of FDG PET images, the distinction between controls and AD patients was 93% sensitive and 93% specific, and even in very mild dementia (at Mini Mental Status Examination (MMSE) 24 or higher) sensitivity was still 84% at 93% specificity. Significantly abnormal metabolism in mild cognitive deficit (MCI) indicates a high risk to develop dementia within the next two years. Reduced neocortical glucose metabolism can probably be detected with FDG PET in AD on average one year before onset of subjective cognitive impairment. In addition to glucose metabolism, specific tracers for dopamine synthesis (18F-F-DOPA) and for (11C-MP4A) are of interest for differentiation among dementia subtypes. Cortical acetylcholine esterase activity (AChE) activity is significantly lower in patients with AD or with dementia with Lewy bodies (DLB) than in age-matched normal controls. In LBD there is also impairment of dopamine synthesis, similar to Parkinson disease. (author) 115 refs

  10. Pet Overpopulation: An Economic Analysis

    OpenAIRE

    Coate, Stephen; Knight, Brian

    2009-01-01

    This paper considers the problem of pet overpopulation. It develops a tractable dynamic model whose positive predictions square well with key features of the current U.S. market for pets. The model is used to understand, from a welfare economic perspective, the sense in which there is \\overpopulation" of pets and the underlying causes of the problem. The paper also employs the model to consider what policies might be implemented to deal with the problem. A calibrated example is developed to i...

  11. PETS 2014: dataset and challenge

    OpenAIRE

    Patino, Luis; Ferryman, James

    2015-01-01

    This paper describes the dataset and vision challenges that form part of the PETS 2014 workshop. The datasets are multisensor sequences containing different activities around a parked vehicle in a parking lot. The dataset scenarios were filmed from multiple cameras mounted on the vehicle itself and involve multiple actors. In PETS2014 workshop, 22 acted scenarios are provided of abnormal behaviour around the parked vehicle. The aim in PETS 2014 is to provide a standard benchmark that indicate...

  12. PET radiopharmaceuticals for neuroreceptor imaging

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Routine clinical PET radiopharmaceuticals for the noninvasive imaging of brain receptors, transporters,and enzymes are commonly labeled with positron emitting nuclides such as carbon-11 or fluorine-18. Certain minimal conditions need to be fulfilled for these PET ligands to be used as imaging agents in vivo. Some of these prerequisites are discussed and examples of the most useful clinical PET radiopharmaceuticals that have found application in the central nervous system are reviewed.

  13. A generalized method of converting CT image to PET linear attenuation coefficient distribution in PET/CT imaging

    International Nuclear Information System (INIS)

    The accuracy of attenuation correction in positron emission tomography scanners depends mainly on deriving the reliable 511-keV linear attenuation coefficient distribution in the scanned objects. In the PET/CT system, the linear attenuation distribution is usually obtained from the intensities of the CT image. However, the intensities of the CT image relate to the attenuation of photons in an energy range of 40 keV–140 keV. Before implementing PET attenuation correction, the intensities of CT images must be transformed into the PET 511-keV linear attenuation coefficients. However, the CT scan parameters can affect the effective energy of CT X-ray photons and thus affect the intensities of the CT image. Therefore, for PET/CT attenuation correction, it is crucial to determine the conversion curve with a given set of CT scan parameters and convert the CT image into a PET linear attenuation coefficient distribution. A generalized method is proposed for converting a CT image into a PET linear attenuation coefficient distribution. Instead of some parameter-dependent phantom calibration experiments, the conversion curve is calculated directly by employing the consistency conditions to yield the most consistent attenuation map with the measured PET data. The method is evaluated with phantom experiments and small animal experiments. In phantom studies, the estimated conversion curve fits the true attenuation coefficients accurately, and accurate PET attenuation maps are obtained by the estimated conversion curves and provide nearly the same correction results as the true attenuation map. In small animal studies, a more complicated attenuation distribution of the mouse is obtained successfully to remove the attenuation artifact and improve the PET image contrast efficiently. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  14. PET and Recycling

    Directory of Open Access Journals (Sweden)

    Funda Sevencan

    2007-08-01

    Full Text Available This review aims to clarify the need of decreasing the environmental effects caused by human and draw attention to the increasing environmental effects of plastics wastes. Plastics consist of organic molecules with high density molecules or polymers. Main resources of plastics are the residue of oil rafineries. Several advantages of plastics, have increased the usage continuously. Polyethylene Terephthalate (PET is the most commonly used plastics. PET is used to protect food, drinking water, fruit juice, alcoholic beverage, and food packing films. By the increasing interest on the environmental effects of plastic wastes, concerns on the recyclable packing materials also grew up. Also the daily use of recyclable containers consisting PET have increased. There are five steps for recycling of plastics. These steps are; using large amounts of plastics, collecting them in a big center, classifying and sorting the plastics, reproducing the polymers and obtaining new products with melted plastics. Providing a healthy recycling of plastics, the consumers should have knowledge and responsibility. The consumer should know what he/she has to do before putting the plastics in the recycling containers. Recycling containers and bags should be placed near the sources of plastic wastes. Consequently, the plastic wastes and environmental problems they cause will be on the agenda in future. [TAF Prev Med Bull. 2007; 6(4: 307-312

  15. Positron emission tomography (PET) for cholangiocarcinoma

    OpenAIRE

    Breitenstein, S; Apestegui, C.; Clavien, P.-A.

    2008-01-01

    The combination of positron emission tomography (PET) with computed tomography (PET-CT) provides simultaneous metabolic and anatomic information on tumors in the same imaging session. Sensitivity of PET/PET-CT is higher for intrahepatic (>90%) than for extrahepatic cholangiocarcinoma (CCA) (about 60%). The detection rate of distant metastasis is 100%. PET, and particularly PET-CT, improves the results and impacts on the oncological management in CCA compared with other imaging modalities. The...

  16. RPC PET: Status and perspectives

    Science.gov (United States)

    Couceiro, M.; Blanco, A.; Ferreira, Nuno C.; Ferreira Marques, R.; Fonte, P.; Lopes, L.

    2007-10-01

    The status of the resistive plate chamber (RPC)-PET technology for small animals is briefly reviewed and its sensitivity performance for human PET studied through Monte-Carlo simulations. The cost-effectiveness of these detectors and their very good timing characteristics open the possibility to build affordable Time of Flight (TOF)-PET systems with very large fields of view. Simulations suggest that the sensitivity of such systems for human whole-body screening, under reasonable assumptions, may exceed the present crystal-based PET technology by a factor up to 20.

  17. Extended suicide with a pet.

    Science.gov (United States)

    Cooke, Brian K

    2013-01-01

    The combination of the killing of a pet and a suicide is a perplexing scenario that is largely unexplored in the literature. Many forensic psychiatrists and psychologists may be unaccustomed to considering the significance of the killing of a pet. The subject is important, however, because many people regard their pets as members of their family. A case is presented of a woman who killed her pet dog and herself by carbon monoxide poisoning. The purpose of this article is to provide an initial exploration of the topic of extended suicide with a pet. Forensic mental health evaluations may have a role in understanding the etiology of this event and in opining as to the culpability of individuals who attempt to or successfully kill a pet and then commit suicide. Because the scientific literature is lacking, there is a need to understand this act from a variety of perspectives. First, a social and anthropological perspective will be presented that summarizes the history of the practice of killing of one's pet, with a focus on the ancient Egyptians. A clinical context will examine what relationship animals have to mental illness. A vast body of existing scientific data showing the relevance of human attachment to pets suggests that conclusions from the phenomena of homicide-suicide and filicide-suicide are applicable to extended suicide with a pet. Finally, recommendations will be proposed for both clinical and forensic psychiatrists faced with similar cases. PMID:24051598

  18. High-voltage pixel detectors in commercial CMOS technologies for ATLAS, CLIC and Mu3e experiments

    CERN Document Server

    Peric,I et al.

    2013-01-01

    High-voltage particle detectors in commercial CMOS technologies are a detector family that allows implementation of low-cost, thin and radiation-tolerant detectors with a high time resolution. In the R/D phase of the development, a radiation tolerance of 1015 neq=cm2 , nearly 100% detection efficiency and a spatial resolution of about 3 μm were demonstrated. Since 2011 the HV detectors have first applications: the technology is presently the main option for the pixel detector of the planned Mu3e experiment at PSI (Switzerland). Several prototype sensors have been designed in a standard 180 nm HV CMOS process and successfully tested. Thanks to its high radiation tolerance, the HV detectors are also seen at CERN as a promising alternative to the standard options for ATLAS upgrade and CLIC. In order to test the concept, within ATLAS upgrade R/D, we are currently exploring an active pixel detector demonstrator HV2FEI4; also implemented in the 180 nm HV process.

  19. High-voltage pixel detectors in commercial CMOS technologies for ATLAS, CLIC and Mu3e experiments

    CERN Document Server

    Peric, Ivan; Backhaus, Malte; Barbero, Marlon; Benoit, Mathieu; Berger, Niklaus; Bompard, Frederic; Breugnon, Patrick; Clemens, Jean-Claude; Dannheim, Dominik; Dierlamm, Alexander; Feigl, Simon; Fischer, Peter; Fougeron, Denis; Garcia-Sciveres, Maurice; Heim, Timon; Hügging, Fabian; Kiehn, Moritz; Kreidl, Christian; Krüger, Hans; La Rosa, Alessandro; Liu, Jian; Lütticke, Florian; Mariñas, Carlos; Meng, Lingxin; Miucci, Antonio; Münstermann, Daniel; Nguyen, Hong Hanh; Obermann, Theresa; Pangaud, Patrick; Perrevoort, Ann-Kathrin; Rozanov, Alexandre; Schöning, André; Schwenker, Benjamin; Wiedner, Dirk

    2013-01-01

    High-voltage particle detectors in commercial CMOS technologies are a detector family that allows implementation of low-cost, thin and radiation-tolerant detectors with a high time resolution. In the R/D phase of the development, a radiation tolerance of 10 15 n eq = cm 2 , nearly 100% detection ef fi ciency and a spatial resolution of about 3 μ m were demonstrated. Since 2011 the HV detectors have fi rst applications: the technology is presently the main option for the pixel detector of the planned Mu3e experiment at PSI (Switzerland). Several prototype sensors have been designed in a standard 180 nm HV CMOS process and successfully tested. Thanks to its high radiation tolerance, the HV detectors are also seen at CERN as a promising alternative to the standard options for ATLAS upgrade and CLIC. In order to test the concept, within ATLAS upgrade R/D, we are currently exploring an active pixel detector demonstrator HV2FEI4; also implemented in the 180 nm HV process

  20. PET Imaging - from Physics to Clinical Molecular Imaging

    Science.gov (United States)

    Majewski, Stan

    2008-03-01

    From the beginnings many years ago in a few physics laboratories and first applications as a research brain function imager, PET became lately a leading molecular imaging modality used in diagnosis, staging and therapy monitoring of cancer, as well as has increased use in assessment of brain function (early diagnosis of Alzheimer's, etc) and in cardiac function. To assist with anatomic structure map and with absorption correction CT is often used with PET in a duo system. Growing interest in the last 5-10 years in dedicated organ specific PET imagers (breast, prostate, brain, etc) presents again an opportunity to the particle physics instrumentation community to contribute to the important field of medical imaging. In addition to the bulky standard ring structures, compact, economical and high performance mobile imagers are being proposed and build. The latest development in standard PET imaging is introduction of the well known TOF concept enabling clearer tomographic pictures of the patient organs. Development and availability of novel photodetectors such as Silicon PMT immune to magnetic fields offers an exciting opportunity to use PET in conjunction with MRI and fMRI. As before with avalanche photodiodes, particle physics community plays a leading role in developing these devices. The presentation will mostly focus on present and future opportunities for better PET designs based on new technologies and methods: new scintillators, photodetectors, readout, software.

  1. First PET Center in Mexico: the power of molecular imaging

    International Nuclear Information System (INIS)

    Positron Emission Tomography (PET) is a non-invasive diagnostic imaging technique modality. It represents the forefront of medical images and was developed as a quantitative technique for imaging biochemical and physiological processes in the human body. PET is unique because it produces images of the body's basic biochemistry or function. Traditional diagnostic techniques such as x-rays, CT scans or MRI, produce images of the body's anatomy or structure. The premise with these techniques is that the change in anatomy or structure that occurs with disease can be seen. However, biochemical processes are also altered with disease and may occur before there is a change gross anatomy. PET is an imaging technique that is used to visualize some of these processes. The development of PET as we know it today began in 1974 with the development of a single ring detector system by Phelps et al. Today, over 350 PET scanners are in use in the world, mainly in the USA (over 140), Europe (particularly in the Anglo-Saxon countries and France) and Japan. Many of these facilities also have their own cyclotron to produce the positron emitters. In the Southern hemisphere, only Australia, Argentina. and recently Mexico, have a very small number of PET facilities. (Author)

  2. Cost-effectiveness of PET and PET/Computed Tomography

    DEFF Research Database (Denmark)

    Gerke, Oke; Hermansson, Ronnie; Hess, Søren; Schifter, Søren; Vach, Werner; Høilund-Carlsen, Poul Flemming

    2015-01-01

    measure by means of incremental cost-effectiveness ratios when considering the replacement of the standard regimen by a new diagnostic procedure. This article discusses economic assessments of PET and PET/computed tomography reported until mid-July 2014. Forty-seven studies on cancer and noncancer...

  3. Get Set for a Pet.

    Science.gov (United States)

    DeRosa, Bill

    1987-01-01

    Describes a game in which students deal with some of the factors involved in being a responsible pet owner. Includes a list of the materials needed for the game and provides the game board and the game pieces, along with a fold-out poster about neutering and spaying pets. (TW)

  4. Synthesis, structural characterization, and antiinflammatory activity of triethylphosphinegold(I) sulfanylpropenoates of the type [(AuPEt3)2xspa] [H2xspa = 3-(aryl)-2-sulfanylpropenoic acid]: an (H2O)6 cluster in the lattice of the complexes [(AuPEt3)2xspa] x 3 H2O.

    Science.gov (United States)

    Barreiro, Elena; Casas, José S; Couce, María D; Gato, Angeles; Sánchez, Agustín; Sordo, José; Varela, José M; Vázquez López, Ezequiel M

    2008-07-21

    Gold complexes of the type [(AuPEt3)2xspa] were prepared by reacting AuPEt3Cl in basic media with the 3-(aryl)-2-sulfanylpropenoic acids H2xspa [x = p, Clp, -o-mp, -p-mp, -o-hp, -p-hp, diBr-o-hp, f, t, -o-py; p = 3-phenyl, Clp = 3-(2-chlorophenyl)-, -o-mp = 3-(2-methoxyphenyl)-, -p-mp = 3-(4-methoxyphenyl)-, -o-hp = 3-(2-hydroxyphenyl)-, -p-hp = 3-(4-hydroxyphenyl)-, diBr-o-hp = 3-(3,5- dibromo-2-hydroxyphenyl)-, f = 3-(2-furyl)-, t = 3-(2-thienyl)-, -o-py = 3-(2-pyridyl); spa = 2-sulfanylpropenoato], and 2-cyclopentylidene-2-sulfanylacetic acid (H2cpa). The complexes were characterized by spectroscopic methods (IR, (1)H, (13)C and (31)P NMR) and mass spectrometry, and the complexes [(AuPEt3)2pspa] x 3 H2O, [(AuPEt3)2-p-hpspa] x 3 H2O, [(AuPEt3)2tspa)] x 3 H2O, and [(AuPEt3)2-o-hpspa] by X-ray diffractometry. The crystals of the first three complexes contain (H2O)6 clusters hydrogen bonded to [(AuPEt3)2xspa]2 dimer units, whereas in the -o-hpspa derivative the hydrogen bonds are between the monomer [(AuPEt3)2-o-hpspa] units. The antiinflammatory activity of the complexes against plantar edema induced by carrageenan in rats is generally significant, with the values for the o-hpspa and tspa derivatives being particularly high. PMID:18563877

  5. Neurotransmission imaging by PET

    International Nuclear Information System (INIS)

    PET studies on neurotransmission in psychological disorders to evaluate abnormal neurotransmission and therapeutic effects are thoroughly reviewed by type of major neurotransmitters. Studies on dopaminergic neurotransmission have focused on the function of dopamine D2 receptors, receptor subtypes, such as the D1 receptor, and ligands, such as transporters. PET studies of dopamine D2 receptor, which began in the early 1980s, have predominantly been performed in schizophrenia, and most have failed to detect any statistically significant differences between schizophrenia patients and controls. The studies in the early 1980s were performed by using [11C]N-methyl-spiperone (NMSP) and [11C]raclopride, ligands for striatal dopamine D2 receptors. [11C]FLB457, which has much higher affinity for D2 receptors than raclopride, began to be used in the 1990s. Dopamine D2 occupancy after drug ingestion has also been investigated to clarify the mechanisms and effects of antipsychotic drugs, and there have also been studies on the effect of aging and personality traits on dopamine D2 receptor levels in healthy subjects. In studies on dopamine receptor subtypes other than D2, dopamine D1 receptors have been studied in connection with assessments of cognitive functions. Most studies on dopamine transporters have been related to drug dependence. Serotonin 5-HT2A receptors have been studied with [11C]NMSP in schizophrenia patients, while studies of another serotonin receptor subtype, 5-HT1A receptors, have been mainly conducted in patients with depression. [11C]NMSP PET showed no difference between schizophrenia patients who had not undergone phamacotherapy and normal subjects. Because serotonin selective reuptake inhibitors (SSRIs) affect serotonin transporters, and abnormalities in serotonin transporters detected in mood disorders, PET ligands for serotonin transporters have increasingly been developed, and serotonin transporters have recently begun to be examined. GABA has been

  6. Neurotransmission imaging by PET

    Energy Technology Data Exchange (ETDEWEB)

    Takano, Akihiro; Suhara, Tetsuya [National Inst. of Radiological Sciences, Chiba (Japan)

    2001-08-01

    PET studies on neurotransmission in psychological disorders to evaluate abnormal neurotransmission and therapeutic effects are thoroughly reviewed by type of major neurotransmitters. Studies on dopaminergic neurotransmission have focused on the function of dopamine D{sub 2} receptors, receptor subtypes, such as the D{sub 1} receptor, and ligands, such as transporters. PET studies of dopamine D{sub 2} receptor, which began in the early 1980s, have predominantly been performed in schizophrenia, and most have failed to detect any statistically significant differences between schizophrenia patients and controls. The studies in the early 1980s were performed by using [{sup 11}C]N-methyl-spiperone (NMSP) and [{sup 11}C]raclopride, ligands for striatal dopamine D{sub 2} receptors. [{sup 11}C]FLB457, which has much higher affinity for D{sub 2} receptors than raclopride, began to be used in the 1990s. Dopamine D{sub 2} occupancy after drug ingestion has also been investigated to clarify the mechanisms and effects of antipsychotic drugs, and there have also been studies on the effect of aging and personality traits on dopamine D{sub 2} receptor levels in healthy subjects. In studies on dopamine receptor subtypes other than D{sub 2}, dopamine D{sub 1} receptors have been studied in connection with assessments of cognitive functions. Most studies on dopamine transporters have been related to drug dependence. Serotonin 5-HT{sub 2A} receptors have been studied with [{sup 11}C]NMSP in schizophrenia patients, while studies of another serotonin receptor subtype, 5-HT{sub 1A} receptors, have been mainly conducted in patients with depression. [{sup 11}C]NMSP PET showed no difference between schizophrenia patients who had not undergone phamacotherapy and normal subjects. Because serotonin selective reuptake inhibitors (SSRIs) affect serotonin transporters, and abnormalities in serotonin transporters detected in mood disorders, PET ligands for serotonin transporters have increasingly

  7. Value of a dixon-based MR/PET attenuation correction sequence for the localization and evaluation of PET-positive lesions

    Energy Technology Data Exchange (ETDEWEB)

    Eiber, Matthias; Holzapfel, Konstantin; Rummeny, Ernst J. [Technische Universitaet Muenchen, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Martinez-Moeller, Axel; Souvatzoglou, Michael; Ziegler, Sibylle; Schwaiger, Markus; Nekolla, Stephan G.; Beer, Ambros J. [Technische Universitaet Muenchen, Department of Nuclear Medicine, Munich (Germany); Pickhard, Anja [Technische Universitaet Muenchen, Department of Otorhinolaryngology, Munich (Germany); Loeffelbein, Dennys [Technische Universitaet Muenchen, Department of Maxillofacial Surgery, Munich (Germany); Santi, Ivan [University of Bologna, Service of Nuclear Medicine, PET Center, Policlinico S.Orsola-Malpighi, Bologna (Italy)

    2011-09-15

    In this study, the potential contribution of Dixon-based MR imaging with a rapid low-resolution breath-hold sequence, which is a technique used for MR-based attenuation correction (AC) for MR/positron emission tomography (PET), was evaluated for anatomical correlation of PET-positive lesions on a 3T clinical scanner compared to low-dose CT. This technique is also used in a recently installed fully integrated whole-body MR/PET system. Thirty-five patients routinely scheduled for oncological staging underwent {sup 18}F-fluorodeoxyglucose (FDG) PET/CT and a 2-point Dixon 3-D volumetric interpolated breath-hold examination (VIBE) T1-weighted MR sequence on the same day. Two PET data sets reconstructed using attenuation maps from low-dose CT (PET{sub AC{sub CT}}) or simulated MR-based segmentation (PET{sub AC{sub MR}}) were evaluated for focal PET-positive lesions. The certainty for the correlation with anatomical structures was judged in the low-dose CT and Dixon-based MRI on a 4-point scale (0-3). In addition, the standardized uptake values (SUVs) for PET{sub AC{sub CT}} and PET{sub AC{sub MR}} were compared. Statistically, no significant difference could be found concerning anatomical localization for all 81 PET-positive lesions in low-dose CT compared to Dixon-based MR (mean 2.51 {+-} 0.85 and 2.37 {+-} 0.87, respectively; p = 0.1909). CT tended to be superior for small lymph nodes, bone metastases and pulmonary nodules, while Dixon-based MR proved advantageous for soft tissue pathologies like head/neck tumours and liver metastases. For the PET{sub AC{sub CT}}- and PET{sub AC{sub MR}}-based SUVs (mean 6.36 {+-} 4.47 and 6.31 {+-} 4.52, respectively) a nearly complete concordance with a highly significant correlation was found (r = 0.9975, p < 0.0001). Dixon-based MR imaging for MR AC allows for anatomical allocation of PET-positive lesions similar to low-dose CT in conventional PET/CT. Thus, this approach appears to be useful for future MR/PET for body regions not

  8. Sparsity-constrained PET image reconstruction with learned dictionaries

    Science.gov (United States)

    Tang, Jing; Yang, Bao; Wang, Yanhua; Ying, Leslie

    2016-09-01

    PET imaging plays an important role in scientific and clinical measurement of biochemical and physiological processes. Model-based PET image reconstruction such as the iterative expectation maximization algorithm seeking the maximum likelihood solution leads to increased noise. The maximum a posteriori (MAP) estimate removes divergence at higher iterations. However, a conventional smoothing prior or a total-variation (TV) prior in a MAP reconstruction algorithm causes over smoothing or blocky artifacts in the reconstructed images. We propose to use dictionary learning (DL) based sparse signal representation in the formation of the prior for MAP PET image reconstruction. The dictionary to sparsify the PET images in the reconstruction process is learned from various training images including the corresponding MR structural image and a self-created hollow sphere. Using simulated and patient brain PET data with corresponding MR images, we study the performance of the DL-MAP algorithm and compare it quantitatively with a conventional MAP algorithm, a TV-MAP algorithm, and a patch-based algorithm. The DL-MAP algorithm achieves improved bias and contrast (or regional mean values) at comparable noise to what the other MAP algorithms acquire. The dictionary learned from the hollow sphere leads to similar results as the dictionary learned from the corresponding MR image. Achieving robust performance in various noise-level simulation and patient studies, the DL-MAP algorithm with a general dictionary demonstrates its potential in quantitative PET imaging.

  9. Bulk and track etching of PET studied by spectrophotometer

    International Nuclear Information System (INIS)

    UV-VIS spectra of poly(ethylene terephthalate) (PET) solutions formed by etching PET in NaOH solution were analyzed with respect to the etching time. A linear relationship between absorptions centered at 4.45 and 5.11 eV with weight loss of PET in NaOH solution was established. The relation was applied to study the influence of UV light illumination on bulk etching of PET and to evaluate pore size of etched-through tracks. It is found that bulk etching of PET can be greatly enhanced by UV illumination in air in the wavelength range around 313 nm. A surface area of about 350 nm in thickness shows a 23 times increase in bulk-etching rate after illuminated for 6 h. The phenomenon is attributed to the oxygen-assisted photo-degradation through generating of new photo-unstable species. The enhancement in bulk etching was immediately reduced as the etching proceeds below the surface with an exponential decay constant of about 1.5 μm-1. Etching of Xe ion irradiated PET films gives extra etching products with similar chemical structure as revealed by spectrophotometer measurements. Quantitative analysis of etching products from latent tracks implies that pores of about 14.6 nm in radius are formed after etching in 0.74 N NaOH at 40 deg. C for 35 min, which is in agreement with the conductometric measurement

  10. Fusion of PET and MRI for Hybrid Imaging

    Science.gov (United States)

    Cho, Zang-Hee; Son, Young-Don; Kim, Young-Bo; Yoo, Seung-Schik

    Recently, the development of the fusion PET-MRI system has been actively studied to meet the increasing demand for integrated molecular and anatomical imaging. MRI can provide detailed anatomical information on the brain, such as the locations of gray and white matter, blood vessels, axonal tracts with high resolution, while PET can measure molecular and genetic information, such as glucose metabolism, neurotransmitter-neuroreceptor binding and affinity, protein-protein interactions, and gene trafficking among biological tissues. State-of-the-art MRI systems, such as the 7.0 T whole-body MRI, now can visualize super-fine structures including neuronal bundles in the pons, fine blood vessels (such as lenticulostriate arteries) without invasive contrast agents, in vivo hippocampal substructures, and substantia nigra with excellent image contrast. High-resolution PET, known as High-Resolution Research Tomograph (HRRT), is a brain-dedicated system capable of imaging minute changes of chemicals, such as neurotransmitters and -receptors, with high spatial resolution and sensitivity. The synergistic power of the two, i.e., ultra high-resolution anatomical information offered by a 7.0 T MRI system combined with the high-sensitivity molecular information offered by HRRT-PET, will significantly elevate the level of our current understanding of the human brain, one of the most delicate, complex, and mysterious biological organs. This chapter introduces MRI, PET, and PET-MRI fusion system, and its algorithms are discussed in detail.

  11. SPECT-PET in Epilepsy and Clinical Approach in Evaluation.

    Science.gov (United States)

    Ergün, Eser Lay; Saygi, Serap; Yalnizoglu, Dilek; Oguz, Kader Karli; Erbas, Belkis

    2016-07-01

    In epilepsy, a detailed history, blood chemistry, routine electroencephalography, and brain MRI are important for the diagnosis of seizure type or epilepsy syndrome for the decision of appropriate drug treatment. Although antiepileptic drugs are mostly successful for controlling epileptic seizures, 20%-30% patients are resistant to medical treatment and continue to have seizures. In this intractable patient group, surgical resection is the primarily preferred treatment option. This particular group of patients should be referred to the epilepsy center for detailed investigation and further treatment. When the results of electroencephalography, MRI, and clinical status are discordant or there is no structural lesion on MRI, ictal-periictal SPECT, and interictal PET play key roles for lateralization or localization of epileptic region and guidance for the subsequent subdural electrode placement in intractable epilepsy. SPECT and PET show the functional status of the brain. SPECT and PET play important roles in the evaluation of epilepsy sydromes in childhood by showing abnormal brain regions. Most of the experience has been gained with (18)FDG-PET, in this respect. (11)C-flumazenil-PET usually deliniates the seizure focus more smaller than (18)FDG-PET and is sensitive in identifying medial temporal sclerosis. (11)C-alpha-methyl-l-tryptophan is helpful in the differentiation of epileptogenic and nonepileptogenic regions in children especially in tuberous sclerosis and multifocal cortical dysplasia for the evaluation of surgery. Finally, when there is concordance among these detailed investigations, resective surgery or palliative procedures can be discussed individually. PMID:27237440

  12. Mechanical and thermal properties of commercial multilayer PET/PP film irradiated with electron-beam

    International Nuclear Information System (INIS)

    The effects of electron-beam irradiation on mechanical and thermal properties, for one commercial flexible food packaging multilayer structure, were studied. The laminated poly(ethylene terephthalate) (PET)/ polypropylene (PP) structure was irradiated up to 60 kGy, using a 1.5 MeV electron beam accelerator, at room temperature in the presence of air. Mechanical properties showed significant changes (p < 0.05). In addition, the DSC analysis, after treatment, showed that the fusion enthalpy and crystallinity of the PET/PP structure components presented significant changes (p < 0.05) with the electron-beam radiation doses applied. It was observed an increase in PP crystallinity while the PET crystallinity decreases. Such decrease in PET crystallinity indicates the predominance of a cross-linking process on the irradiated PET layer; responsible for the increase in some mechanical properties of the studied film. (author)

  13. Topography of pulmonary structure and function in man using positron emission tomography (PET) with special reference to methodology and normal physiology

    International Nuclear Information System (INIS)

    Positron emission tomography (PET) allows regional quantification of specific tracer compounds to be made within a tomographic slice of the body. The present thesis which is methodological and descriptive, centers on in vivo measurements of regional lung compartments (gas, red cells, plasma and extravascular tissue) and ventilation and blood flow in normal subjects. A method of measuring regional lung hematocrit (rH) was developed and rH was found to be found to be 90% of the peripheral hematocrit in normal subjects. No significant regional variations within the lung fields were found in normal subjects or in patients with anemia or pneumonia, which enables the pulmonary whole blood volume to be regionally quantified using a single vascular tracer. This allowed a deeper examination of the interrelationship between the different lung compartments and their variation in the gravity dependent axis and during hyperinflation. Smokers were found to have higher extravascular density than non-smokers. By combining measurement of ventilation and .VA/.Q, methods were developed to 1. correct the measured .VA/.Q for incomplete equilibrium of 13N within the alveolar space. 2. calculate regional pulmonary perfusion. By further combining these measurements with measurements of vascular and extravascular lung volumes 1. relationship between ventilation and vascular and extravascular volumes were explored and found to be consistent with the theory that ventilation is determined by the elastic properties of lung tissue and 2. relationships between blood flow and blood volume (transit times) were investigated. We conclude that blood volume plays a significant role in the matching of ventilation and perfusion and that blood flow is fairly well matched by blood volumes, thus reducing the gravitational impact on capillary transit time and hematocrit ratio which might be of rheological importance. (au)

  14. Topography of pulmonary structure and function in man using positron emission tomography (PET) with special reference to methodology and normal physiology

    Energy Technology Data Exchange (ETDEWEB)

    Brundin, L.H. (MRC, Cyclotron Unit and Dept. of Medicine, Hammersmith Hospital, London (United Kingdom) and Lund Univ. (Sweden). Dept. of Clinical Physiology)

    1992-01-01

    Positron emission tomography (PET) allows regional quantification of specific tracer compounds to be made within a tomographic slice of the body. The present thesis which is methodological and descriptive, centers on in vivo measurements of regional lung compartments (gas, red cells, plasma and extravascular tissue) and ventilation and blood flow in normal subjects. A method of measuring regional lung hematocrit (rH) was developed and rH was found to be found to be 90% of the peripheral hematocrit in normal subjects. No significant regional variations within the lung fields were found in normal subjects or in patients with anemia or pneumonia, which enables the pulmonary whole blood volume to be regionally quantified using a single vascular tracer. This allowed a deeper examination of the interrelationship between the different lung compartments and their variation in the gravity dependent axis and during hyperinflation. Smokers were found to have higher extravascular density than non-smokers. By combining measurement of ventilation and [sup .]V[sub A]/[sup .]Q, methods were developed to 1. correct the measured [sup .]V[sub A]/[sup .]Q for incomplete equilibrium of [sup 13]N within the alveolar space. 2. calculate regional pulmonary perfusion. By further combining these measurements with measurements of vascular and extravascular lung volumes 1. relationship between ventilation and vascular and extravascular volumes were explored and found to be consistent with the theory that ventilation is determined by the elastic properties of lung tissue and 2. relationships between blood flow and blood volume (transit times) were investigated. We conclude that blood volume plays a significant role in the matching of ventilation and perfusion and that blood flow is fairly well matched by blood volumes, thus reducing the gravitational impact on capillary transit time and hematocrit ratio which might be of rheological importance. (au).

  15. Topography of pulmonary structure and function in man using positron emission tomography (PET) with special reference to methodology and normal physiology

    Energy Technology Data Exchange (ETDEWEB)

    Brundin, L.H. [MRC, Cyclotron Unit and Dept. of Medicine, Hammersmith Hospital, London (United Kingdom) and Lund Univ. (Sweden). Dept. of Clinical Physiology

    1992-12-31

    Positron emission tomography (PET) allows regional quantification of specific tracer compounds to be made within a tomographic slice of the body. The present thesis which is methodological and descriptive, centers on in vivo measurements of regional lung compartments (gas, red cells, plasma and extravascular tissue) and ventilation and blood flow in normal subjects. A method of measuring regional lung hematocrit (rH) was developed and rH was found to be found to be 90% of the peripheral hematocrit in normal subjects. No significant regional variations within the lung fields were found in normal subjects or in patients with anemia or pneumonia, which enables the pulmonary whole blood volume to be regionally quantified using a single vascular tracer. This allowed a deeper examination of the interrelationship between the different lung compartments and their variation in the gravity dependent axis and during hyperinflation. Smokers were found to have higher extravascular density than non-smokers. By combining measurement of ventilation and {sup .}V{sub A}/{sup .}Q, methods were developed to 1. correct the measured {sup .}V{sub A}/{sup .}Q for incomplete equilibrium of {sup 13}N within the alveolar space. 2. calculate regional pulmonary perfusion. By further combining these measurements with measurements of vascular and extravascular lung volumes 1. relationship between ventilation and vascular and extravascular volumes were explored and found to be consistent with the theory that ventilation is determined by the elastic properties of lung tissue and 2. relationships between blood flow and blood volume (transit times) were investigated. We conclude that blood volume plays a significant role in the matching of ventilation and perfusion and that blood flow is fairly well matched by blood volumes, thus reducing the gravitational impact on capillary transit time and hematocrit ratio which might be of rheological importance. (au).

  16. FDG PET imaging dementia

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Byeong Cheol [Kyungpook National University Medical School and Kyungpook National University Hospital, Daegu (Korea, Republic of)

    2007-04-15

    Dementia is a major burden for many countries including South Korea, where life expectancy is continuously growing and the proportion of aged people is rapidly growing. Neurodegenerative disorders, such as, Alzheimer disease, dementia with Lewy bodies, frontotemporal dementia. Parkinson disease, progressive supranuclear palsy, corticobasal degeneration, Huntington disease, can cause dementia, and cerebrovascular disease also can cause dementia. Depression or hypothyroidism also can cause cognitive deficits, but they are reversible by management of underlying cause unlike the forementioned dementias. Therefore these are called pseudodementia. We are entering an era of dementia care that will be based upon the identification of potentially modifiable risk factors and early disease markers, and the application of new drugs postpone progression of dementias or target specific proteins that cause dementia. Efficient pharmacologic treatment of dementia needs not only to distinguish underlying causes of dementia but also to be installed as soon as possible. Therefore, differential diagnosis and early diagnosis of dementia are utmost importance. F-18 FDG PET is useful for clarifying dementing diseases and is also useful for early detection of the disease. Purpose of this article is to review the current value of FDG PET for dementing diseases including differential diagnosis of dementia and prediction of evolving dementia.

  17. Neuropsychiatry: PET and SPECT

    International Nuclear Information System (INIS)

    Functional brain imaging with PET and SPECT have a definitive and well established role in the investigation of a variety of conditions such as dementia, epilepsy and drug addiction. With these methods it is possible to detect early rCBF (regional Cerebral Blood Flow) changes seen in dementia (even before clinical symptoms) and differentiate Alzheimer's disease from other dementias by means of the rCBF pattern change. 18-F-FDG PET imaging is a useful tool in partial epilepsy because both rCBF and brain metabolism are compromised at the epileptogenic focus. During the seizure, rCBF dramatically increases locally. Using SPECT it is possible to locate such foci with 97% accuracy. In drug addiction, particularly with cocaine, functional imaging has proven to be very sensitive to detect brain flow and metabolism derangement early in the course of this condition. These findings are important in many ways: prognostic value, they are used as a powerful reinforcement tool and to monitor functional recovery with rehabilitation. There are many other conditions in which functional brain imaging is of importance such as acute stroke treatment assessment, trauma rehabilitation and in psychiatric and abnormal movement diseases specially with the development of receptor imaging (au)

  18. FDG PET imaging dementia

    International Nuclear Information System (INIS)

    Dementia is a major burden for many countries including South Korea, where life expectancy is continuously growing and the proportion of aged people is rapidly growing. Neurodegenerative disorders, such as, Alzheimer disease, dementia with Lewy bodies, frontotemporal dementia. Parkinson disease, progressive supranuclear palsy, corticobasal degeneration, Huntington disease, can cause dementia, and cerebrovascular disease also can cause dementia. Depression or hypothyroidism also can cause cognitive deficits, but they are reversible by management of underlying cause unlike the forementioned dementias. Therefore these are called pseudodementia. We are entering an era of dementia care that will be based upon the identification of potentially modifiable risk factors and early disease markers, and the application of new drugs postpone progression of dementias or target specific proteins that cause dementia. Efficient pharmacologic treatment of dementia needs not only to distinguish underlying causes of dementia but also to be installed as soon as possible. Therefore, differential diagnosis and early diagnosis of dementia are utmost importance. F-18 FDG PET is useful for clarifying dementing diseases and is also useful for early detection of the disease. Purpose of this article is to review the current value of FDG PET for dementing diseases including differential diagnosis of dementia and prediction of evolving dementia

  19. PET AND PET-CT: PHYSICAL PRINCIPLE AND MEDICAL APLICATIONS

    OpenAIRE

    Rusu, V.; Cipriana Ştefănescu

    2007-01-01

    Positron emission tomography (PET) is a noninvasive imaging method that can “see” the metabolisms inside the living cells. It involves the acquisition of functional images based on the detection of radiation coming from the positron emission of a radiotracer administered to the patient. This radiotracer can be a metabolic analog, like is the case of glucose analog 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (18FDG), the most commonly used PET radiotracer. PET images of the human body are used to...

  20. Choke-mode damped structure design for the Compact Linear Collider main linac

    CERN Document Server

    Zha, Hao; Grudiev, Alexej; Huang, Wenhui; Shi, Jiaru; Tang, Chuanxiang; Wuensch, Walter

    2012-01-01

    Choke-mode damped structures are being studied as an alternative design to waveguide damped structures for the main linac of the Compact Linear Collider (CLIC). Choke-mode structures have the potential for lower pulsed temperature rise and simpler and less expensive fabrication. An equivalent circuit model based on transmission line theory for higher-order-mode damping is presented. Using this model, a new choke geometry is proposed and the wakefield performance is verified using GDFIDL. This structure has a comparable wakefield damping effect to the baseline design which uses waveguide damping. A prototype structure with the same iris dimensions and accelerating gradient as the nominal CLIC design, but with the new choke geometry, has been designed for high-power tests. DOI: 10.1103/PhysRevSTAB.15.122003

  1. PET i prekirurgisk evaluering av epilepsi

    OpenAIRE

    2010-01-01

    PET in presurgical evaluation of epilepsy. Background: Today, at Rikshospitalet PET medical center, FDG is used as a tracer in the PET investigations during the presurgical evaluation of patients with epilepsy. The purpose of this paper is to see if FGD-PET gives additional information compared with EEG and MR. Another purpose was to find out whether there is a need for new ligands, and which ones. Material and methods: All epilepsy order forms to FDG-PET at Rikshopitalet, during 2007...

  2. Preparation and biocompatibility of grafted functional β-cyclodextrin copolymers from the surface of PET films

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Yan, E-mail: yan_jiang_72@126.com [College of Materials Science and Engineering, Changzhou University, Changzhou 213164, Jiangsu (China); Liang, Yuan; Zhang, Hongwen [College of Materials Science and Engineering, Changzhou University, Changzhou 213164, Jiangsu (China); Zhang, Weiwei [College of Life Science, Agriculture and Forestry, Qiqihar University, Qiqihar 161006, Heilongjiang (China); Tu, Shanshan [College of Materials Science and Engineering, Changzhou University, Changzhou 213164, Jiangsu (China)

    2014-08-01

    The hydrophobic inert surface of poly(ethylene terephthalate) (PET) film has limited its practical bioapplications, in which case, better biocompatibility should be achieved by surface modification. In this work, the copolymer of functional β-cyclodextrin derivatives and styrene grafted surfaces was prepared via surface-initiated atom transfer radical polymerization (SI-ATRP) on initiator-immobilized PET. The structures, composition, properties, and surface morphology of the modified PET films were characterized by fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), contact angle measurement, and scanning electronic microscopy (SEM). The results show that the surface of PET films was covered by a thick targeted copolymer layer, and the hydrophobic surface of PET was changed into an amphiphilic surface. The copolymer-grafted surfaces were also shown good biocompatibility on which SGC-7901 A549 and A549/DDP cells readily attached and proliferated, demonstrating that the functional copolymer-grafted PET films could be a promising alternative to biomaterials especially for tissue engineering. - Highlights: • The PET film was grafted by functional β-CD copolymers, which owns amphiphilicity. • The surface of grafted PET film by copolymers enhanced the cell adhesion and growth. • The biocompatible PET film may be used in tissue engineering and cell cultivation.

  3. Role of PET-CT in cancers around the esophagus and the bronchus

    International Nuclear Information System (INIS)

    Fluorodeoxyglucose-positron emission tomography (FDG-PET) is a useful modality for cancer diagnosis. It, however, often needs assistance from morphological imaging modalities such as CT or MRI for accurate diagnosis. PET-CT is a combination of a functional imaging tool. PET, and a morphological imaging tool, CT. The areas around the esophagus and bronchi contain complicated anatomical structures and display many variations of physiological uptake of FDG, which makes PET interpretation difficult. PET-CT solves this problem and allows easier and more confident interpretations. Though MRI may be superior to FDG-PET in diagnosis of primary cancer, FDG-PET is very useful in detecting unknown primary cancers which are negative on CT or MRI. In staging, it is possible to accurately localize nodal or other metastases, which has a bearing on surgical or radiation treatment planning. There are some issues in determining therapeutic efficacy, such as optimal timing of evaluation and avoiding false positive findings due to postradiation inflammation. Nonetheless, there is a report recommending evaluation using the change of standardized uptake value (SUV) of FDG uptake in the tumor. Radiation therapy planning using PET-CT has been tried in several institutes and new challenges using PET-CT are to be expected. (author)

  4. Preparation and biocompatibility of grafted functional β-cyclodextrin copolymers from the surface of PET films

    International Nuclear Information System (INIS)

    The hydrophobic inert surface of poly(ethylene terephthalate) (PET) film has limited its practical bioapplications, in which case, better biocompatibility should be achieved by surface modification. In this work, the copolymer of functional β-cyclodextrin derivatives and styrene grafted surfaces was prepared via surface-initiated atom transfer radical polymerization (SI-ATRP) on initiator-immobilized PET. The structures, composition, properties, and surface morphology of the modified PET films were characterized by fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), contact angle measurement, and scanning electronic microscopy (SEM). The results show that the surface of PET films was covered by a thick targeted copolymer layer, and the hydrophobic surface of PET was changed into an amphiphilic surface. The copolymer-grafted surfaces were also shown good biocompatibility on which SGC-7901 A549 and A549/DDP cells readily attached and proliferated, demonstrating that the functional copolymer-grafted PET films could be a promising alternative to biomaterials especially for tissue engineering. - Highlights: • The PET film was grafted by functional β-CD copolymers, which owns amphiphilicity. • The surface of grafted PET film by copolymers enhanced the cell adhesion and growth. • The biocompatible PET film may be used in tissue engineering and cell cultivation

  5. Scintillation crystals required for PET

    International Nuclear Information System (INIS)

    In PET, inorganic scintillator crystals are used to record γ rays produced by the annihilation of positrons emitted by injected tracers. The ultimate performance of the camera is strongly tied to both the physical and scintillation properties of the crystals. For this reason, researchers have investigated virtually all known scintillator crystals for possible use in PET. Despite this massive research effort, only a few different scintillators have been found that have a suitable use. Two recently developed scintillator crystals (LSO and GSO), appears to surpass all previously used materials in most respects and promises to be the basis for the next generation of PET cameras. (authors)

  6. PET and PET/CT in tumour of undetermined origin

    International Nuclear Information System (INIS)

    In this presentation the following conclusions were obtained regarding the use of PET and PET/CT in patient with cancer of unknown primary: 1. Detection of the primary one in 1/3 at 1/2 of patient. 2. It detects metastases in other places in 50%. 3. It changes the initial therapy planned in 1/3 at 1/2 of patient. 4. Useful in initial phases of protocol study to limit the other procedures. After standard evaluation. Before advanced protocol. 5. PET/CT study increases the % of primary detection, although in a non significant way vs. PET. 6. They are required more studies to value their utility to a more objective manner. (Author)

  7. Physical Impacts of Compaction Treatments on PET Textile Vascular Prostheses

    Directory of Open Access Journals (Sweden)

    Meriem Azaiez

    2011-06-01

    Full Text Available Textile cardiovascular prostheses are woven or knitted structures made generally from biocompatible polyester fibres. After production, they have to undergo special treatments before packaging such as compaction. This treatment is necessary to reduce porosity especially for knitted structures, but it can modify poly(ethylene terephthalate (PET polymer’s properties. We have studied the effect of chemical and thermal compaction process parameters on physical properties of PET with DSC and XRD techniques. The obtained results show changes of glass transition temperature according to compaction parameters. A multiple melting peaks thermograms were observed for untreated and most compacted samples indicating differences between crystallites sizes. The compaction treatment involves an increase of PET crystallites size because of molecular bonds rearrangement among the polymeric chains. With DRX, we have showed crystallites size increases for compacted samples when compared with untreated samples. This increase is particularly important in perpendicular direction to (010 crystallographic plane.

  8. Physical Impacts of Compaction Treatments on Pet Textile Vascular Prostheses

    Directory of Open Access Journals (Sweden)

    Meriem Azaiez

    2010-12-01

    Full Text Available Textile cardiovascular prostheses are woven or knitted structures made generally from biocompatible polyester fibres. After production, they have to undergo special treatments before packaging such as compaction. This treatment is necessary to reduce porosity especially for knitted structures, but it can modify poly(ethylene terephthalate (PET polymer’s properties. We have studied the effect of chemical and thermal compaction process parameters on physical properties of PET with DSC and XRD techniques. The obtainedresults show changes of glass transition temperature according to compaction parameters. A multiple melting peaks thermograms were observed for untreated and most compacted samples indicating differences between crystallites sizes. The compaction treatment involves an increase of PET crystallites size because of molecular bonds rearrangement among the polymeric chains. With DRX, we have showed crystallites size increases for compacted samples when compared with untreated samples. This increase is particularly important in perpendicular direction to (010 crystallographic plane.

  9. Measurement of the branching ratios for the Standard Model Higgs decays into muon pairs and into Z boson pairs at a 1.4 TeV CLIC

    CERN Document Server

    AUTHOR|(SzGeCERN)701211; Bozovic-Jelisavcic, Ivanka; Grefe, Christian; Kacarevic, Goran; Lukic, Strahinja; Pandurovic, Mila; Roloff, Philipp Gerhard; Smiljanic, Ivan

    2016-01-01

    The measurement of the Higgs production cross-section times the branching ratios for its decays into μ+μ- and ZZ* pairs at a 1.4 TeV CLIC collider is investigated in this paper. The Standard Model Higgs boson with a mass of 126 GeV is dominantly produced via WW fusion in e+e- collisions at 1.4 TeV centre-of-mass energy. Analyses for both decay channels are based on a full simulation of the CLIC_ILD detector. All relevant physics and beam-induced background processes are taken into account. An integrated luminosity of 1.5 ab 1 and unpolarised beams are assumed. For the H-->ZZ* decay, the purely hadronic final state (ZZ*--> qq ̄qq ̄) is considered as well as ZZ* decays into two jets and two leptons (ZZ*--> qq ̄l+l- ). It is shown that the branching ratio for the Higgs decay into a muon pair times the Higgs production cross-section can be measured with 38% statistical uncertainty. It is also shown that the statistical uncertainty of the Higgs branching fraction for decay into a Z boson pair times the Hi...

  10. Adhesion of nitrile rubber to UV-assisted surface chemical modified PET fabric, part II: Interfacial characterization of MDI grafted PET

    Science.gov (United States)

    Razavizadeh, Mahmoud; Jamshidi, Masoud

    2016-08-01

    Fiber to rubber adhesion is an important subject in rubber industry. It is well known that surface treatment (i.e. physical, mechanical and chemical) is an effective method to improve interfacial bonding of fibers and/or fabrics to rubbers. UV irradiation is an effective method which has been used to increase fabric-rubber interfacial interactions. In this research UV assisted chemical modification of PET fabrics was used to increase PET to nitrile rubber (NBR) adhesion. Nitrile rubber is a perfect selection as fuel and oil resistant rubber. However it has weak bonding to PET fabric. For this purpose PET fabric was carboxylated under UV irradiation and then methylenediphenyl diisocyanate (MDI) was grafted on carboxylated PET. The chemical composition of the fabric before and after surface treatment was investigated by X-ray photoelectron spectroscopy (XPS). The sectional morphology of the experimental PET fibers and the interface between rubber compound and PET fabric was studied using scanning electron microscope (SEM). The morphology and structure of the product were analyzed by an energy dispersive X-ray spectrometer (EDX). FTIR-ATR and H NMR analysis were used to assess surface modifications on the PET irradiated fabrics.

  11. PET/TAC in Oncology; PET/TAC en Oncologia

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez V, A.M. [Especialista en Medicina Nuclear, Profa. Depto. Radiologia de la Facultad de Medicina, Universidad Complutense de Madrid, Madrid (Spain)

    2007-07-01

    From this presentation of PET-TAC in oncology the following advantages on the conventional PET are obtained: 1. More short study and stadium in one session. 2. It adds the information of both techniques. 3. Better localization of leisure: affected organ, stadium change (neck, mediastinum, abdomen). 4. Reduction of false positive (muscle, brown fat, atelectasis, pneumonias, intestine, urinary vials, etc.). 5. Reduction of negative false. 6. Reduction of not conclusive. 7. More understandable for other specialists. 8. Biopsies guide. 9. Planning radiotherapy.

  12. SPECT and PET imaging in Parkinson's disease

    International Nuclear Information System (INIS)

    Parkinson disease (PD) is the second most common neurodegenerative disorder after Alzheimer's dementia (AD) with a prevalence of 2/1000 in the whole population. This number increases to 2/100 in the aging population and the total number of patients will rise further with increasing life expectancy. Modern imaging techniques such as SPECT (single photon emission tomography) and PET(positron emission tomography) can visualize function and molecular structures in the living human brain and are important clinical and research tools in the evaluation of FP. Because the brain dopamine (DA) system plays a pivotal role in the pathogenesis of PD and related disorders most SPECT and PET studies in PD deal with different aspects of DA-ergic function. However, PD also affects noradrenaline (NA) and serotonin (5HT) producing neurons which contribute to non-motor symptoms. Recent SPECT and PET studies also address this issue. SPECT is a technique which is widely available and is increasingly used in the clinical evaluation of PF patients. With SPECT and specific 123I labelled ligands pre- and postsynaptic structures of the nigrostriatal DA-ergic system can be labelled and visualized. Thus, it is possible to detect and to quantify lesions of the DA-ergic system on the one hand and lesions of the striatal output neurons on the other. This technique also enables studies of pharmacological interactions at the receptor level. With the help of β-CIT, a cocaine derivative, and other similar ligands DA transporters (DATs) can be labelled on DA-ergic nerve terminals. DAT imaging clearly differentiates between normal controls and PD patients even in early stages of the disease. Patients with subcortical vascular encephalopathy presenting with symptoms resembling PD ('lower body Parkinson') can be distinguished with high specificity and sensitivity. PET has the advantage of a better resolution and quantification and a larger number of tracers have mainly been used as a research tool. With

  13. NEUROPSIQUIATRIA: PET Y SPECT

    Directory of Open Access Journals (Sweden)

    Juan Carlos Quintana F

    2002-01-01

    Full Text Available Existen numerosas indicaciones claramente establecidas para el uso del SPECT y PET en patología neuro-psiquiátrica, particularmente en el estudio de demencias, epilepsia y adicción a drogas. Estos métodos permiten detectar precozmente (aun antes de las manifestaciones clínicas cambios en la perfusión y metabolismo cerebral en pacientes con demencias. Es posible además diferenciar la enfermedad de Alzheimer de otras causas de demencia, analizando el patrón de la alteración neuro- funcional. En epilepsia parcial, tanto el metabolismo como la perfusión están alterados en el foco epileptogénico, lo que puede ser detectado con F-18FDG PET. Durante la crisis epiléptica, el flujo sanguíneo puede aumentar dramáticamente en el foco epileptogénico, lo que puede ser detectado con SPECT con 97% de certeza. En pacientes drogadictos, especialmente a la cocaína, estos métodos han demostrado ser muy sensibles para la detección precoz de cambios en el flujo y metabolismo cerebral, lo que es clínicamente importante en varios aspectos: 1 Tiene valor pronóstico (neuro-funcional, 2 Se puede usar para aumentar la adherencia a la terapia y 3 Permite evaluar objetivamente la recuperación funcional. Existen muchas otras indicaciones presentes y futuras, por ejemplo: en la monitorización de la revascularización en accidentes vasculares cerebrales agudos, rehabilitación post TEC, estudio de patología psiquiátrica y movimientos anormales especialmente con el desarrollo de radioligandosFunctional brain imaging with PET and SPECT have a definitive and well established role in the investigation of a variety of conditions such as dementia, epilepsy and drug addiction. With these methods it is possible to detect early rCBF (regional Cerebral Blood Flow changes seen in dementia (even before clinical symptoms and differentiate Alzheimer's disease from other dementias by means of the rCBF pattern change. 18-F-FDG PET imaging is a useful tool in partial

  14. Measuring PET scanner sensitivity

    International Nuclear Information System (INIS)

    Sensitivity parameters derived from a plot of a scanner's true coincidence count (TCC) rates as a function of activity in a 20 cm cylindrical phantom have no direct link to image quality. Noise equivalent count (NEC) rate curves, which incorporate the noise effects of subtracting the randoms and scatter count components provide a direct link between image signal-to-noise ratios and the scatter, randoms and trues coincidence count rates. The authors have measured TCC and NEC curves with a standardized 20 cm diameter nylon cylinder for five different PET scanners with several scanner-collimator combinations. In addition, the authors have compared TCC and NEC curves on one scanner with those from an Alderson brain phantom

  15. Specification and estimation of sources of bias affecting neurological studies in PET/MR with an anatomical brain phantom

    International Nuclear Information System (INIS)

    Selection of reconstruction parameters has an effect on the image quantification in PET, with an additional contribution from a scanner-specific attenuation correction method. For achieving comparable results in inter- and intra-center comparisons, any existing quantitative differences should be identified and compensated for. In this study, a comparison between PET, PET/CT and PET/MR is performed by using an anatomical brain phantom, to identify and measure the amount of bias caused due to differences in reconstruction and attenuation correction methods especially in PET/MR. Differences were estimated by using visual, qualitative and quantitative analysis. The qualitative analysis consisted of a line profile analysis for measuring the reproduction of anatomical structures and the contribution of the amount of iterations to image contrast. The quantitative analysis consisted of measurement and comparison of 10 anatomical VOIs, where the HRRT was considered as the reference. All scanners reproduced the main anatomical structures of the phantom adequately, although the image contrast on the PET/MR was inferior when using a default clinical brain protocol. Image contrast was improved by increasing the amount of iterations from 2 to 5 while using 33 subsets. Furthermore, a PET/MR-specific bias was detected, which resulted in underestimation of the activity values in anatomical structures closest to the skull, due to the MR-derived attenuation map that ignores the bone. Thus, further improvements for the PET/MR reconstruction and attenuation correction could be achieved by optimization of RAMLA-specific reconstruction parameters and implementation of bone to the attenuation template. -- Highlights: • Comparison between PET, PET/CT and PET/MR was performed with a novel brain phantom. • The performance of reconstruction and attenuation correction in PET/MR was studied. • A recently developed brain phantom was found feasible for PET/MR imaging. • Contrast reduction

  16. Chemical recycling of post-consumer PET: structural characterization of terephthalic acid and the effect of Alkaline Hydrolysis at low temperature; Reciclagem quimica do PET pos-consumo: caracterizacao estrutural do acido tereftalico e efeito da hidrolise alcalina em baixa temperatura

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, Talitha Granja; Almeida, Yeda Medeiros Bastos de; Vinhas, Gloria Maria, E-mail: gmvinhas@yahoo.com.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Engenharia Quimica

    2014-09-15

    Due to the environmental impact caused by PET packaging disposal, this material recycling has been thoroughly discussed and evaluated. In particular, chemical recycling enables achievement of the monomers that are used in PET resin manufacture: ethylene glycol (EG) and terephthalic acid (PTA). Therefore, studies for this process optimization are important from environmental and economic points of view. The present study investigated certain parameters that influence the depolymerization reaction of PET post-consumer via alkaline hydrolysis in order to obtain PTA. Assays were performed at 70 °C by varying the concentration of sodium hydroxide and the reaction time. The best results were obtained at 10.82 mol L{sup -1} NaOH and 9 h reaction time. Consequently, it was possible to prove this process viability, once analyses by infrared and nuclear magnetic resonance confirmed that PTA was obtained in all reactions performed. (author)

  17. Pets and the immunocompromised person

    Science.gov (United States)

    ... affect the cat's immune system. This puts your cat at risk of other infections that may be spread to humans. Feed your pet only commercially prepared food and treats. Animals can get sick from undercooked ...

  18. 10 "Poison Pills" for Pets

    Science.gov (United States)

    ... Care Animal Welfare Veterinary Careers Public Health 10 "Poison Pills" for Pets Anyone who takes medication prescribed ... of all phone calls to the ASPCA Animal Poison Control Center (APCC) are about human medications. Your ...

  19. PET and PET/CT in tumour of undetermined origin; PET y PET/CT en tumor de origen indeterminado

    Energy Technology Data Exchange (ETDEWEB)

    Garcia O, J.R. [Nuclear Medicine and Molecular Imaging, PET/CT, Centro Medico ABC, Mexico D.F. (Mexico)

    2007-07-01

    In this presentation the following conclusions were obtained regarding the use of PET and PET/CT in patient with cancer of unknown primary: 1. Detection of the primary one in 1/3 at 1/2 of patient. 2. It detects metastases in other places in 50%. 3. It changes the initial therapy planned in 1/3 at 1/2 of patient. 4. Useful in initial phases of protocol study to limit the other procedures. After standard evaluation. Before advanced protocol. 5. PET/CT study increases the % of primary detection, although in a non significant way vs. PET. 6. They are required more studies to value their utility to a more objective manner. (Author)

  20. 89Zr Radiochemistry for PET

    OpenAIRE

    Severin, G. W.; Engle, J W; Nickles, R.J.; Barnhart, T. E.

    2011-01-01

    The positron emitting isotope 89Zr is an ideal radiolabel for PET imaging of monoclonal antibodies (mAbs). This article reviews the chemistry and physics involved in production, separation, chelation, and labeling of 89Zr mAbs.

  1. Selecting Safe Pets (For Parents)

    Science.gov (United States)

    ... Reports? What to Say Vaccines: Which Ones & When? Smart School Lunches Emmy-Nominated Video "Cerebral Palsy: Shannon's ... pets. If you're interested in rabbits, the House Rabbit Society is an excellent resource — visit its ...

  2. Preventing Ticks on Your Pets

    Science.gov (United States)

    ... Tickborne diseases abroad Borrelia miyamotoi Borrelia mayonii Preventing ticks on your pets Recommend on Facebook Tweet Share ... your cats without first consulting your veterinarian! Kill Ticks on Dogs A pesticide product that kills ticks ...

  3. Disaster Preparedness for Your Pet

    Science.gov (United States)

    ... Do not let your pet interact with other animals Use disinfectant to clean the cage and litter box Leptospirosis is a bacterial disease found in the urine of infected animals that can cause kidney damage and affect other ...

  4. [F-18]fluoro-meta-L-tyrosine is a better PET tracer than [F-18]fluoro-L-dopa for the delineation of dopaminergic structures in the human brain

    International Nuclear Information System (INIS)

    Fluorine-18 labelled fluoro-m-L-tyrosine (FmLtyr) and fluoro-L-Dopa (F-Dopa) have been synthesized, and the utility of FmLtyr for PET investigations of dopaminergic brain regions has been compared to that of F-dopa. Experimental results from both monkey and human studies indicate that FmLtyr gives better delineation of striatum, and is a better PET tracer than F-dopa

  5. Radiation monitoring of PET staff

    International Nuclear Information System (INIS)

    Full text: Positron emission tomography (PET) is becoming a common diagnostic tool in hospitals, often located in and employing staff from the Nuclear Medicine or Radiology departments. Although similar in some ways, staff in PET departments are commonly found to have the highest radiation doses in the hospital environment due to unique challenges which PET tracers present in administration as well as production. The establishment of a PET centre with a dedicated cyclotron has raised concerns of radiation protection to the staff at the WA PET Centre and the Radiopharmaceutical Production and Development (RAPID) team. Since every PET centre has differing designs and practices, it was considered important to closely monitor the radiation dose to our staff so that improvements to practices and design could be made to reduce radiation dose. Electronic dosimeters (MGP DMC 2000XB), which have a facility to log time and dose at 10 second intervals, were provided to three PET technologists and three PET nurses. These were worn in the top pocket of their lab coats throughout a whole day. Each staff member was then asked to note down their duties throughout the day and also note the time they performed each duty. The duties would then correlate with the dose with which the electronic monitor recorded and an estimate of radiation dose per duty could be given. Also an estimate of the dose per day to each staff member could be made. PET nurses averaged approximately 20 μ8v per day getting their largest dose from caring for occasional problematic patients. Smaller doses of a 1-2 μ8v were recorded for injections and removing cannulas. PET technologists averaged approximately 15 μ8v per day getting their largest dose of 1-5μ8v mainly from positioning of patients and sometimes larger doses due to problematic patients. Smaller doses of 1-2 μ5v were again recorded for injections and removal of cannulas. Following a presentation given to staff, all WA PET Centre and RAPID staff

  6. Biometric Recognition for Pet Animal

    OpenAIRE

    Santosh Kumar; Sanjay Kumar Singh

    2014-01-01

    Missing, swapping, false insurance claims and reallocation of pet animals (dog) are global problems throughout the world and research done to solve this problem is minimal. Traditional biometrics and non-biometrics methods have their own boundaries and they fail to provide competent level of security to pet animal (dog). The work on animal identification based on their phenotype appearance (coat patterns) has been an active research area in recent years and automatic face recognition for...

  7. PET/TAC in Oncology

    International Nuclear Information System (INIS)

    From this presentation of PET-TAC in oncology the following advantages on the conventional PET are obtained: 1. More short study and stadium in one session. 2. It adds the information of both techniques. 3. Better localization of leisure: affected organ, stadium change (neck, mediastinum, abdomen). 4. Reduction of false positive (muscle, brown fat, atelectasis, pneumonias, intestine, urinary vials, etc.). 5. Reduction of negative false. 6. Reduction of not conclusive. 7. More understandable for other specialists. 8. Biopsies guide. 9. Planning radiotherapy

  8. Nutritional sustainability of pet foods.

    Science.gov (United States)

    Swanson, Kelly S; Carter, Rebecca A; Yount, Tracy P; Aretz, Jan; Buff, Preston R

    2013-03-01

    Sustainable practices meet the needs of the present without compromising the ability of future generations to meet their needs. Applying these concepts to food and feed production, nutritional sustainability is the ability of a food system to provide sufficient energy and essential nutrients required to maintain good health in a population without compromising the ability of future generations to meet their nutritional needs. Ecological, social, and economic aspects must be balanced to support the sustainability of the overall food system. The nutritional sustainability of a food system can be influenced by several factors, including the ingredient selection, nutrient composition, digestibility, and consumption rates of a diet. Carbon and water footprints vary greatly among plant- and animal-based ingredients, production strategy, and geographical location. Because the pet food industry is based largely on by-products and is tightly interlinked with livestock production and the human food system, however, it is quite unique with regard to sustainability. Often based on consumer demand rather than nutritional requirements, many commercial pet foods are formulated to provide nutrients in excess of current minimum recommendations, use ingredients that compete directly with the human food system, or are overconsumed by pets, resulting in food wastage and obesity. Pet food professionals have the opportunity to address these challenges and influence the sustainability of pet ownership through product design, manufacturing processes, public education, and policy change. A coordinated effort across the industry that includes ingredient buyers, formulators, and nutritionists may result in a more sustainable pet food system. PMID:23493530

  9. Two 352 MHz push pull linac pairs to generate two drive beams for CLIC multibunch operation

    International Nuclear Information System (INIS)

    The present note describes a drive beam generation scheme for multibunch operation at 1 TeV continuous mode and the luminosity of 1034 cm-2s-1. This rather conventional scheme is essentially based on acceleration with 352 MHz superconducting cavities. Contrary to a previous proposal for single bunch operation, an independent push pull linac pair per drive beam is foreseen mainly for the following reasons. Twice as many drive bunchlets per 352 MHz period halves the required charge per bunchlet. With two trains, the bunchlet deceleration variation inside one train is reduced. A good drive beam to RF efficiencies are obtained through matching of the train energy profile to the decelerating wake pattern in the drive linac. The reduced wake variation makes it feasible to preshape the train energy profile to the required ramp by simple phase shifting of the 352 MHz voltage in the superconducting cavities in conjunction with a small harmonics correction. The layout of the system consists of the 30 GHz accelerating structures, 30 GHz transfer structures, fourth harmonics (1408 MHz) superconducting structures, push pull fundamental (352 MHz) linac pair and switch yards. Emphasis has been put on wall-plug to main beam efficiency and minimum capital cost to the extent possible for the concept chosen. The issues of studies are harmonic synthesis of an optimum acceleration ramp, beam loading compensation for fundamental frequency cavities, acceleration of 22 bunchlets, fourth harmonic cavities, wall plug to main beam efficiency and RF deflectors. The main disadvantage of the scheme seem to be: a) high bunchlet charge of 45 n C. b) overall efficiency of only 10.1%, essentially because of the limited stored RF energy in the 352 MHz structures, which limits the number of drive bunchlet trains per pulse. c) significant amount of RF and cryogenics hardware for complete drive beam generation complex. The main advantage appears to be: a) no long drive beam transport lines, no 180 and

  10. Developments of PET radioligands for NMDA receptors

    International Nuclear Information System (INIS)

    Aim: There has been a great demand for developments of the radioligands to visualize the N-methyl-D-aspartate (NMDA) receptors by PET/SPECT. We have recently synthesized two C-11 labeled antagonists for the glycine-binding site on NMDA receptors. The aim of this work is to examine for their in vitro and in vivo binding characteristics, and to evaluate their potentials as PET radioligands for the NMDA receptors. Materials and methods: Two C-11 labeled 4-hydroxy-2-quinolones (1 and 2) were synthesized by conventional methylation of the corresponding phenols with [11C]methyl iodide. In vitro and ex vivo quantitative autoradiographs with imaging plate, as well as animal PET, were employed in order to evaluate their in vitro and in vivo binding to the NMDA receptors. Results: The compound 1 showed the specific binding to rat brain slices with higher localization in the hippocampus and cerebral cortex than in the cerebellum. Both glycine antagonists and agonists (glycine and D-serine) inhibited the in vitro binding of 1. On the other hand, the compound 2 displayed the specific binding to rat brain slices with no regional difference. Very interestingly, glycine agonists gave no significant change in the in vitro binding of 2, while glycine antagonists strongly inhibited the binding. Ex vivo autoradiography and monkey PET studies showed that 1 localizes only in the cerebellum, whereas 2 localizes in the cortex regions than in the cerebellum. Simultaneous injection with non-radioactive 1 or 2 (2 mg/kg) reduced the radioactivity to their non-specific level. Conclusion: The present studies indicated that the structural change of 4-hydroxy-2-quinolones results in the great change in both in vitro and in vivo binding characteristics of the antagonists. We have recently reported that in vivo binding of 1 ([11C]L-703,717) is inhibited by high content of endogenous glycine and D-serine, and that 1 localizes only in the cerebellum having low content of the agonists. The present in

  11. The implementation of PET technology in Brazil

    International Nuclear Information System (INIS)

    According to the Brazilian Geography and Statistics Institute, Brazil has an estimated population of 188 million inhabitants spread over 8,500,000 km2: The distribution of resident population in major regions of Brazil is shown: North Region - 7.6%; Northeast Region - 28.1%; Southeast Region - 42.6%; South Region - 14.8%; Central West Region - 6.9%. Nuclear Medicine is growing fast in Brazil and this has resulted in an increasing demand for radioisotopes and radiopharmaceuticals. Positron emission tomography (PET), which is a non-invasive molecular imaging procedure, is one of the causes of this increase. PET detects changes in metabolic activities, which may take place before any detectable change in anatomical structure occurs. PET is used to help diagnose and to plan and assess the treatment of cancer, heart disease, and brain disorders. Taking into account all these advantages, it was decided to start the production of PET radiopharmaceuticals at IPEN - Energy and Nuclear Research Institute of CNEN - the Brazilian National Nuclear Energy Commission, located in the city of Sao Paulo, the largest city in Brazil. The production of FDG started in 1998. In 2003, a second FDG production unit was installed at IEN - Nuclear Engineering Institute of CNEN - in Rio de Janeiro, the second largest city in Brazil. Both have much experience in radioisotope and radiopharmaceutical production, and both centres have had cyclotrons for a long time. It is interesting that the production of FDG has increased more than a factor of 17 since 2000 in Brazil. One of the greatest advantages of PET radiopharmaceuticals is due to their short lives. On the other hand, this is also a problem because it means that the production centre needs to be located not too far from the place where it will be used. This can limit the population access to PET technology. Taking into account this scenario and considering that short-lived radioisotope production was a State monopoly until 2006, the

  12. Pet fish radiography: technique and case history reports

    International Nuclear Information System (INIS)

    Radiography can be used to aid in the diagnosis and treatment of pet fish diseases. Handling, restraint and radiographic technique for the radiographic examination of pet fish is described. Quality diagnostic images can be obtained with standard radiographic equipment and radiographic techniques. Fishes with undifferentiated sarcoma, swim bladder herniation and scoliosis are three clinical examples that are described where radiography was used in the management of the patient. Conventional radiography appears to be best for evaluating skeletal and swim bladder diseases. Alternate imaging techniques such as computed tomography and magnetic resonance imaging may enhance the evaluation of coelomic soft tissue structures

  13. Cardiovascular PET-CT imaging: a new frontier?

    Science.gov (United States)

    Adamson, P D; Williams, M C; Newby, D E

    2016-07-01

    Cardiovascular positron-emission tomography combined with computed tomography (PET-CT) has recently emerged as an imaging technology with the potential to simultaneously describe both anatomical structures and physiological processes in vivo. The scope for clinical application of this technique is vast, but to date this promise has not been realised. Nonetheless, significant research activity is underway to explore these possibilities and it is likely that the knowledge gained will have important diagnostic and therapeutic implications in due course. This review provides a brief overview of the current state of cardiovascular PET-CT and the likely direction of future developments. PMID:26951964

  14. Cyclotron, positrons and PET [positron emission tomography]. An overview

    International Nuclear Information System (INIS)

    PET (positron emission tomography) is a powerful new scientific tool which is capable of revealing biochemical transformations while they are occurring in the brain and other organs in the living human body. The application of PET to problems in biology and medicine is dominated by the short half-life of the isotopes used to prepare the radiotracers. The most commonly used positron emitting isotopes are carbon-11, fluorine-18, nitrogen-13, and oxygen-15 which have half-lives of 20.4, 110, 10 and 2 minutes, respectively. Their incorporation into radiotracers having diverse chemical structures and biochemical specificities has allowed the study of blood flow, sugar metabolism, oxygen metabolism, neurotransmission, enzyme activity and binding sites for therapeutic drugs and substances of abuse. PET research is most commonly carried out at a Cyclotron-PET Center (cyclotron, positron emission tomography, chemistry laboratory) where the short-lived isotopes can be produced and used efficiently. The number of Cyclotron-PET Centers has grown from 4 in 1976 to several dozen in 1988 and the number is expected to double in the next five years attesting to the vitality of the field and the current and anticipated contributions to research in biology and medicine

  15. Lung tumor segmentation in PET images using graph cuts.

    Science.gov (United States)

    Ballangan, Cherry; Wang, Xiuying; Fulham, Michael; Eberl, Stefan; Feng, David Dagan

    2013-03-01

    The aim of segmentation of tumor regions in positron emission tomography (PET) is to provide more accurate measurements of tumor size and extension into adjacent structures, than is possible with visual assessment alone and hence improve patient management decisions. We propose a segmentation energy function for the graph cuts technique to improve lung tumor segmentation with PET. Our segmentation energy is based on an analysis of the tumor voxels in PET images combined with a standardized uptake value (SUV) cost function and a monotonic downhill SUV feature. The monotonic downhill feature avoids segmentation leakage into surrounding tissues with similar or higher PET tracer uptake than the tumor and the SUV cost function improves the boundary definition and also addresses situations where the lung tumor is heterogeneous. We evaluated the method in 42 clinical PET volumes from patients with non-small cell lung cancer (NSCLC). Our method improves segmentation and performs better than region growing approaches, the watershed technique, fuzzy-c-means, region-based active contour and tumor customized downhill. PMID:23146420

  16. Brain dopamine receptors in relation to clinical PET-studies

    International Nuclear Information System (INIS)

    A number of published PET Models are discussed with regard to their structure and some of the underlying assumptions. Results of experiments with spiperone and N-methylspiperone in the rat and human brain, which challenge some of these assumptions, are summarized. (author). 37 refs.; 6 figs.; 1 tab

  17. Diagnosis of maxillofacial tumor with L-3-[18F]-fluoro-alpha-methyltyrosine (FMT) PET. A comparative study with FDG-PET

    International Nuclear Information System (INIS)

    The objective of this study was to compare L-3-[18F]-fluoro-α-methyltyrosine (FMT)-positron emission tomography (PET) and 2-[18F]-fluoro-2-deoxy-D-glucose (FDG)-PET in the differential diagnosis of maxillofacial tumors. This study included 36 patients (16 males, 20 females; 31-90 years old) with untreated malignant tumors (34 squamous cell carcinoma, one mucoepidermoid carcinoma, one rhabdomyosarcoma) and seven patients (five males, two females; 32-81 years old) with benign lesions. In all patients, both FMT-PET and FDG-PET were performed within two weeks before biopsy or treatment of the lesions. To evaluate the diagnostic usefulness of FMT-PET and FDG-PET, visual interpretation and semiquantitative analysis were performed. PET images were rated according to the contrast of tumor uptake as compared with background, and were statistically analyzed. As a semiquantitative analysis, standardized uptake values (SUV) of the primary tumors were measured, and the SUV data were analyzed using receiver operating characteristic (ROC) curves. The mean SUV of the malignant lesions were significantly higher than those of the benign lesions in both FMT-PET (2.62±1.58 vs. 1.20±0.30, p<0.01) and FDG-PET (9.17±5.06 vs. 3.14±1.34, p<0.01). A positive correlation (r=0.567, p<0.0001, n=46) was noted between FMT and FDG. ROC analysis revealed that there was no statistically significant difference in SUVs between FMT and FDG for differentiating malignant tumors. In 27 of 36 patients, FMT-PET had better contrast of malignant tumor visualization to the surrounding normal structures by visual assessment (p<0.005, binomial proportion test). Differential diagnosis of FMT-PET based on the uptake in maxillofacial tumors is equivalent to FDG-PET. However, the contrast of FMT uptake between maxillofacial tumors and the surrounding normal structures is higher than that of FDG, indicating the possibility of accurate diagnosis of maxillofacial tumors by FMT-PET. (author)

  18. CTF3 Drive Beam Accelerating Structures

    CERN Document Server

    Jensen, E

    2002-01-01

    The 3 GHz drive beam accelerator of the CLIC Test Facility CTF3, currently under construction at CERN, will be equipped with 16 novel SICA (Slotted Iris – Constant Aperture) accelerating structures. The slotted irises couple out the potentially disruptive induced transverse HOM energy to integrated silicon carbide loads (dipole mode Q's below 20). The use of nose cones for detuning allows a constant inner aperture (34 mm). The structures will be 1.2 m long and consist of 34 cells. A first 6 cell prototype structure has been tested successfully up to power levels of 100 MW (nominal: 30 MW), corresponding to surface electric field levels of 180 MV/m.

  19. PET-CT: Evolving role in hadron therapy

    International Nuclear Information System (INIS)

    Computer-assisted fused-image and/or single-machine-integrated PET-CT can show early tissue biochemical changes with improved anatomic resolution, often before there is any structural change. This approach enables the clinician to view and assess the patient's body from a biochemical perspective. In an era of rapidly evolving 3D-conformal hadron treatment, accurate target delineation is a crucial factor in optimization of clinical results. Using PET-CT for better target delineation improves the ability to escalate tumor dose and to minimize dose to adjacent normal tissues, thereby enhancing the potential for improved efficacy of hadron therapy. This paper reviews some of the basic-science underpinnings of PET-CT, and highlights some important findings in the early clinical work thus far performed

  20. Gamma camera based FDG PET in oncology

    International Nuclear Information System (INIS)

    Positron Emission Tomography(PET) was introduced as a research tool in the 1970s and it took about 20 years before PET became an useful clinical imaging modality. In the USA, insurance coverage for PET procedures in the 1990s was the turning point, I believe, for this progress. Initially PET was used in neurology but recently more than 80% of PET procedures are in oncological applications. I firmly believe, in the 21st century, one can not manage cancer patients properly without PET and PET is very important medical imaging modality in basic and clinical sciences. PET is grouped into 2 categories; conventional (c) and gamma camera based (CB) PET. CBPET is more readily available utilizing dual-head gamma cameras and commercially available FDG to many medical centers at low cost to patients. In fact there are more CBPET in operation than cPET in the USA. CBPET is inferior to cPET in its performance but clinical studies in oncology is feasible without expensive infrastructures such as staffing, rooms and equipments. At Ajou university Hospital, CBPET was installed in late 1997 for the first time in Korea as well as in Asia and the system has been used successfully and effectively in oncological applications. Our was the fourth PET operation in Korea and I believe this may have been instrumental for other institutions got interested in clinical PET. The following is a brief description of our clinical experience of FDG CBPET in oncology

  1. Positron sources for electron-positron colliders application to the ILC and CLIC

    CERN Document Server

    CERN. Geneva

    2008-01-01

    The increased demanding qualities for positron sources dedicated to e+e- colliders pushed on investigations oriented on new kinds of e+ sources. The different kinds of positron sources polarized and no polarized are considered. Their main features (intensity, emittance) are described and analysed. Comparison between the different sources is worked out. The characteristics of the positron beam available in the collision point are greatly depending on the capture device and on the positron accelerator. Different kinds of capture systems are considered and their qualities, compared. Intense positron sources which are necessary for the colliders require intense incident beams (electrons or photons). The large number of pairs created in the targets leads to important energy deposition and so, thermal heating, which associated to temperature gradients provoke mechanical stresses often destructive. Moreover, the important Coulomb collisions, can affect the atomic structure in crystal targets and the radiation resist...

  2. A sensitiviy analysis for the stabilization of the CLIC main beam quadrupoles

    CERN Document Server

    Janssens, S; Artoos, K; Fernandez Carmona, P; Hauviller, C

    2010-01-01

    In particle colliders (like the LHC), particles are highly accelerated in a circular beam pipe before the collision. However, due to the curved trajectory of the particles, they are also loosing energy because of the so-called Bremsstrahlung. In order to bypass this fundamental limitation imposed by circular beams, the next generation of particle colliders will accelerate two straight beams of particles before the collision. One of them, the Compact Linear Collider, is currently under study at CERN. The machine is constituted of a huge number of accelerating structures (used to accelerate the particles) and quadrupoles (electromagnets used to focus the particles). The latter ones are required to be stable at the nanometer level. This extreme stability has to be guaranteed by active vibration isolation from all types of disturbances like ground vibrations, ventilation, cooling system, or acoustic noise. Because of the huge number of quadrupoles (about 4000), it is critical that the strategy adopted for the act...

  3. PET/MRI for Preoperative Planning in Patients with Soft Tissue Sarcoma

    DEFF Research Database (Denmark)

    Loft Jakobsen, Annika; Jensen, Karl Erik; L�fgren, Johan;

    2013-01-01

    Clinical positron emission tomography (PET)/magnetic resonance imaging (MRI) acquisition protocols may improve the evaluation of soft tissue sarcomas (STS) prior to surgical planning. We examined two patients with lower extremity STS using a Siemens Biograph mMR PET/MRI scanner and the glucose...... analogue 18F-fluoro-deoxyglucose (FDG). We investigated clinically relevant tumor volumes and evaluated the relations to skeletal periosteum and nerve bundles. The patient scans suggest that FDG PET/MRI improved the edge detection, and invasion of tumor tissue into important adjacent anatomical structures...... can be evaluated. FDG PET/MRI also provided additional information compared to conventional Gadolinium enhanced MR imaging. The findings were proven by subsequent pathological examination of the resected tumor tissue. In the future, clinical FDG PET/MRI may be an important modality for preoperative...

  4. PET/CT in malignant melanoma: contrast-enhanced CT versus plain low-dose CT

    International Nuclear Information System (INIS)

    The aim of this study was to evaluate the diagnostic value of contrast-enhanced CT (CECT) versus non-enhanced low-dose CT (NECT) in the staging of advanced malignant melanoma with 18F-fluordeoxyglucose (FDG) positron emission tomography (PET)/CT. In total, 50 18F-FDG PET/CT examinations were performed in 50 patients with metastasized melanoma. For attenuation correction, whole-body NECT was performed followed by diagnostic CECT with contrast agent. For the whole-body PET, 18F-FDG was applied. Criteria for evaluation were signs of vital tumour tissue (extent of lesions, contrast enhancement, maximum standardized uptake value >2.5). Findings suspicious for melanoma were considered lesions. NECT, CECT and 18F-FDG PET were evaluated separately, followed by combined analysis of PET/NECT and PET/CECT. Findings were verified histologically and/or by follow-up (>6 months). Overall, 232 lesions were analysed, and 151 proved to be metastases. The sensitivity of NECT, CECT, PET, PET/NECT and PET/CECT was 62, 85, 90, 97 and 100%, and specificity was 52, 63, 88, 93 and 93%, respectively. Compared to CECT, NECT obtained additional false-negative results: lymph node (n = 19) and liver/spleen metastases (n = 9). Misinterpreted physiological structures mainly caused additional false-positive findings (n = 17). In combined analysis of PET/NECT, six false-positive [other tumours (n = 2), inflammatory lymph nodes (n = 2), inflammatory lung lesion (n = 1), blood vessel (n = 1)] and five false-negative findings [liver (n = 3), spleen (n = 1), lymph node metastases (n = 1)] remained. On PET/CECT, six false-positive [inflammatory lymph nodes (n = 3), other tumours (n = 2), inflammatory lung lesion (n = 1)] and no false-negative findings occurred. However, additional false findings on PET/NECT (6 of 232) did not change staging compared to PET/CECT. Our results indicate that it is justified to perform PET/NECT instead of PET/CECT for melanoma staging. (orig.)

  5. Parasites in pet reptiles

    Directory of Open Access Journals (Sweden)

    Mavri Urška

    2011-05-01

    Full Text Available Abstract Exotic reptiles originating from the wild can be carriers of many different pathogens and some of them can infect humans. Reptiles imported into Slovenia from 2000 to 2005, specimens of native species taken from the wild and captive bred species were investigated. A total of 949 reptiles (55 snakes, 331 lizards and 563 turtles, belonging to 68 different species, were examined for the presence of endoparasites and ectoparasites. Twelve different groups (Nematoda (5, Trematoda (1, Acanthocephala (1, Pentastomida (1 and Protozoa (4 of endoparasites were determined in 26 (47.3% of 55 examined snakes. In snakes two different species of ectoparasites were also found. Among the tested lizards eighteen different groups (Nematoda (8, Cestoda (1, Trematoda (1, Acanthocephala (1, Pentastomida (1 and Protozoa (6 of endoparasites in 252 (76.1% of 331 examined animals were found. One Trombiculid ectoparasite was determined. In 563 of examined turtles eight different groups (Nematoda (4, Cestoda (1, Trematoda (1 and Protozoa (2 of endoparasites were determined in 498 (88.5% animals. In examined turtles three different species of ectoparasites were seen. The established prevalence of various parasites in reptiles used as pet animals indicates the need for examination on specific pathogens prior to introduction to owners.

  6. Specific recommendations for accurate and direct use of PET-CT in PET guided radiotherapy for head and neck sites

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, C. M., E-mail: christopher.thomas@gstt.nhs.uk; Convery, D. J.; Greener, A. G. [Guy' s and St. Thomas’ NHS Foundation Trust, Medical Physics Department, St. Thomas’ Hospital, London SE1 7EH (United Kingdom); Pike, L. C.; Baker, S.; Woods, E. [Division of Imaging Sciences and Biomedical Engineering, King' s College London, King' s Health Partners, St. Thomas’ Hospital, London SE1 7EH (United Kingdom); Hartill, C. E. [Guy' s and St. Thomas’ NHS Foundation Trust, Radiotherapy, Clinical Outpatients Clinic, St. Thomas’ Hospital, London SE1 7EH (United Kingdom)

    2014-04-15

    Purpose: To provide specific experience-based guidance and recommendations for centers wishing to develop, validate, and implement an accurate and efficient process for directly using positron emission tomography-computed tomography (PET-CT) for the radiotherapy planning of head and neck cancer patients. Methods: A PET-CT system was modified with hard-top couch, external lasers and radiotherapy immobilization and indexing devices and was subject to a commissioning and quality assurance program. PET-CT imaging protocols were developed specifically for radiotherapy planning and the image quality and pathway tested using phantoms and five patients recruited into an in-house study. Security and accuracy of data transfer was tested throughout the whole data pathway. The patient pathway was fully established and tested ready for implementation in a PET-guided dose-escalation trial for head and neck cancer patients. Results: Couch deflection was greater than for departmental CT simulator machines. An area of high attenuation in the couch generated image artifacts and adjustments were made accordingly. Using newly developed protocols CT image quality was suitable to maintain delineation and treatment accuracy. Upon transfer of data to the treatment planning system a half pixel offset between PET and CT was observed and corrected. By taking this into account, PET to CT alignment accuracy was maintained below 1 mm in all systems in the data pathway. Transfer of structures delineated in the PET fusion software to the radiotherapy treatment planning system was validated. Conclusions: A method to perform direct PET-guided radiotherapy planning was successfully validated and specific recommendations were developed to assist other centers. Of major concern is ensuring that the quality of PET and CT data is appropriate for radiotherapy treatment planning and on-treatment verification. Couch movements can be compromised, bore-size can be a limitation for certain immobilization

  7. Specific recommendations for accurate and direct use of PET-CT in PET guided radiotherapy for head and neck sites

    International Nuclear Information System (INIS)

    Purpose: To provide specific experience-based guidance and recommendations for centers wishing to develop, validate, and implement an accurate and efficient process for directly using positron emission tomography-computed tomography (PET-CT) for the radiotherapy planning of head and neck cancer patients. Methods: A PET-CT system was modified with hard-top couch, external lasers and radiotherapy immobilization and indexing devices and was subject to a commissioning and quality assurance program. PET-CT imaging protocols were developed specifically for radiotherapy planning and the image quality and pathway tested using phantoms and five patients recruited into an in-house study. Security and accuracy of data transfer was tested throughout the whole data pathway. The patient pathway was fully established and tested ready for implementation in a PET-guided dose-escalation trial for head and neck cancer patients. Results: Couch deflection was greater than for departmental CT simulator machines. An area of high attenuation in the couch generated image artifacts and adjustments were made accordingly. Using newly developed protocols CT image quality was suitable to maintain delineation and treatment accuracy. Upon transfer of data to the treatment planning system a half pixel offset between PET and CT was observed and corrected. By taking this into account, PET to CT alignment accuracy was maintained below 1 mm in all systems in the data pathway. Transfer of structures delineated in the PET fusion software to the radiotherapy treatment planning system was validated. Conclusions: A method to perform direct PET-guided radiotherapy planning was successfully validated and specific recommendations were developed to assist other centers. Of major concern is ensuring that the quality of PET and CT data is appropriate for radiotherapy treatment planning and on-treatment verification. Couch movements can be compromised, bore-size can be a limitation for certain immobilization

  8. Introduction of a stack-phantom for PET

    International Nuclear Information System (INIS)

    Aim: We have previously developed a new flexible phantom system for SPECT, i.e. 'the stack phantom' (Eur. J. Nucl. Med. 27, No.2, 131-139, 2000). The unique feature of this phantom system is that it allows studies with, as well as without major degrading impacts from photon attenuation and Compton scattering. The specific aim of this work was to further develop the system with special reference to PET. Material and methods: The principle of the phantom concept is discrete sampling of 3D objects by a series of equidistant 2D planes. The 2D planes are a digitised set of 2D sections, representing the radioactivity distribution in the object of interest. Using a grey scale related to the radioactivity concentration, selected images are printed by radioactive ink on thin paper sheets and stacked into the 3D structure with low-density or with tissue equivalent material in between. Using positron emitting radionuclides, the paper sheets alone may not be sufficiently thick to avoid annihilation losses due to escaping positrons. In order to investigate the amount of additional material needed, a spot of radioactivity (18F) was printed out and subsequently covered by adding thin plastic films (0.055mm) on both sides of the paper. Short PET scans (ECAT 921) were performed and the count-rate was registered after each additional layer of plastic cover. A first prototype, a cylindrical cold-spot phantom was constructed on the basis of these results. Nine identical sheets were printed out and first mounted in between 4 mm plates of polystyrene (density 1.04 g/cm3). After a PET-scan, the paper sheets were re-mounted in between a low-density material (Divinycell, H30, density 0.03 g/cm3) before repeating the PET scan. Results: For 18F, the number of registered annihilation photons increased with increasing number of plastic sheets from 70% for the pure paper sheet to about 100% with 0.5 mm plastic cover on each side. PET of the low-density stacked cold spot phantom demonstrated

  9. Quantitative PET imaging with the 3T MR-BrainPET

    International Nuclear Information System (INIS)

    The new hybrid imaging technology of MR-PET allows for simultaneous acquisition of versatile MRI contrasts and the quantitative metabolic imaging with PET. In order to achieve the quantification of PET images with minimal residual error the application of several corrections is crucial. In this work we present our results on quantification with the 3T MR BrainPET scanner

  10. PET and PET/CT in oncology: the key of diagnostic challenge

    International Nuclear Information System (INIS)

    In this presentation authors present use of positron emission tomography (PET) in oncology. This lecture is divided to the following parts: (1) Assessment of treatment response; (2) Treatment monitoring by PET: clinical examples; (3) PET for early response assessment; (4) Use of PET in Radiotherapy planning

  11. Unparalleled impact of PET, PET-CT and PET-MRI on the day to day practice of medicine

    International Nuclear Information System (INIS)

    The past 4 decades have witnessed a true revolution in medical imaging. The introduction of single photon emission computed tomography (SPEeT), x-ray computed tomography (CT), positron emission tomography (PET), and magnetic resonance imaging (MRI) have brought about a truly unprecedented era in medicine. While structural imaging with either CT or MRI have been of great value for specialties in medicine such as surgery and radiation therapy, the impact of molecular imaging with either SPECT or PET has been much wider in scope. By now, it has become evident that most diseases and disorders are initiated at the molecular level and may or may not eventually translate to structural abnormalities. Thus, relying on structural imaging alone may prevent accurate detection, and therefore, early interventions for many serious disorders such as cancer and cardiovascular diseases. When the diseases are detected at the structural level, they may be irreversible and cannot be treated effectively. Also, for most human disorders, physicians employ treatments that are only effective in a relatively small segment of the affected patients. This would mean that frequently, they may decide to change the course of treatment because of failure of the initial intervention. Again, structural imaging techniques are quite insensitive for demonstrating the efficacy of most drugs soon after they are initiated, and as such, are inadequate for guiding the clinicians about their decision about adopting alternate therapies. In contrast, molecular imaging techniques allow detecting of failure early on, and therefore, allow shifting to other drugs. Finally, structural imaging techniques are non-specific and cannot differentiate between active and inactive processes. Therefore, many patients will be subjected to invasive and costly procedures based on nonspecific information provided by modalities such as CT and MRI

  12. Children's drawings and attachment to pets.

    Science.gov (United States)

    Kidd, A H; Kidd, R M

    1995-08-01

    To help confirm the concept that distances placed between the self and other figures in children's drawings represent emotional distances, 242 pet-owning and 35 nonpet-owning kindergartners through eighth graders drew pictures of themselves, a pet, and/or a family member. Owners drew pets significantly closer than family-figures although the younger the child, the greater the distance between self and pet. Older children drew themselves holding pets significantly more often, but younger children placed the family-figure between the self and the pet significantly more often. There were no significant gender differences in self-figure/pet-figure distances, but cats, dogs, caged animals, and farm animals were placed significantly closer to self-figures than were fish. Over-all, owners were clearly emotionally closer to pets than to family members, but nonowners were as close emotionally to family members as were owners. PMID:7501763

  13. PET/MRI in cancer patients

    DEFF Research Database (Denmark)

    Kjær, Andreas; Loft, Annika; Law, Ian;

    2013-01-01

    described include brain tumors, pediatric oncology as well as lung, abdominal and pelvic cancer. In general the cases show that PET/MRI performs well in all these types of cancer when compared to PET/CT. However, future large-scale clinical studies are needed to establish when to use PET/MRI. We envision......Combined PET/MRI systems are now commercially available and are expected to change the medical imaging field by providing combined anato-metabolic image information. We believe this will be of particular relevance in imaging of cancer patients. At the Department of Clinical Physiology, Nuclear...... Medicine & PET at Rigshospitalet in Copenhagen we installed an integrated PET/MRI in December 2011. Here, we describe our first clinical PET/MR cases and discuss some of the areas within oncology where we envision promising future application of integrated PET/MR imaging in clinical routine. Cases...

  14. Initial clinical results for breath-hold CT-based processing of respiratory-gated PET acquisitions

    Energy Technology Data Exchange (ETDEWEB)

    Fin, Loic; Daouk, Joel; Morvan, Julie; Esper, Isabelle El; Saidi, Lazhar; Meyer, Marc-Etienne [Amiens University Hospital, Nuclear Medicine Department, Amiens (France); Bailly, Pascal [Amiens University Hospital, Nuclear Medicine Department, Amiens (France); CHU d' Amiens, Service de Medecine Nucleaire, unite TEP, Hopital Sud, Amiens cedex (France)

    2008-11-15

    Respiratory motion causes uptake in positron emission tomography (PET) images of chest structures to spread out and misregister with the CT images. This misregistration can alter the attenuation correction and thus the quantisation of PET images. In this paper, we present the first clinical results for a respiratory-gated PET (RG-PET) processing method based on a single breath-hold CT (BH-CT) acquisition, which seeks to improve diagnostic accuracy via better PET-to-CT co-registration. We refer to this method as ''CT-based'' RG-PET processing. Thirteen lesions were studied. Patients underwent a standard clinical PET protocol and then the CT-based protocol, which consists of a 10-min List Mode RG-PET acquisition, followed by a shallow end-expiration BH-CT. The respective performances of the CT-based and clinical PET methods were evaluated by comparing the distances between the lesions' centroids on PET and CT images. SUV{sub MAX} and volume variations were also investigated. The CT-based method showed significantly lower (p=0.027) centroid distances (mean change relative to the clinical method =-49%; range =-100% to 0%). This led to higher SUV{sub MAX} (mean change =+33%; range =-4% to 69%). Lesion volumes were significantly lower (p=0.022) in CT-based PET volumes (mean change =-39%: range =-74% to -1%) compared with clinical ones. A CT-based RG-PET processing method can be implemented in clinical practice with a small increase in radiation exposure. It improves PET-CT co-registration of lung lesions and should lead to more accurate attenuation correction and thus SUV measurement. (orig.)

  15. Initial clinical results for breath-hold CT-based processing of respiratory-gated PET acquisitions

    International Nuclear Information System (INIS)

    Respiratory motion causes uptake in positron emission tomography (PET) images of chest structures to spread out and misregister with the CT images. This misregistration can alter the attenuation correction and thus the quantisation of PET images. In this paper, we present the first clinical results for a respiratory-gated PET (RG-PET) processing method based on a single breath-hold CT (BH-CT) acquisition, which seeks to improve diagnostic accuracy via better PET-to-CT co-registration. We refer to this method as ''CT-based'' RG-PET processing. Thirteen lesions were studied. Patients underwent a standard clinical PET protocol and then the CT-based protocol, which consists of a 10-min List Mode RG-PET acquisition, followed by a shallow end-expiration BH-CT. The respective performances of the CT-based and clinical PET methods were evaluated by comparing the distances between the lesions' centroids on PET and CT images. SUVMAX and volume variations were also investigated. The CT-based method showed significantly lower (p=0.027) centroid distances (mean change relative to the clinical method =-49%; range =-100% to 0%). This led to higher SUVMAX (mean change =+33%; range =-4% to 69%). Lesion volumes were significantly lower (p=0.022) in CT-based PET volumes (mean change =-39%: range =-74% to -1%) compared with clinical ones. A CT-based RG-PET processing method can be implemented in clinical practice with a small increase in radiation exposure. It improves PET-CT co-registration of lung lesions and should lead to more accurate attenuation correction and thus SUV measurement. (orig.)

  16. Proton Therapy Verification with PET Imaging

    OpenAIRE

    Zhu, Xuping; Fakhri, Georges El

    2013-01-01

    Proton therapy is very sensitive to uncertainties introduced during treatment planning and dose delivery. PET imaging of proton induced positron emitter distributions is the only practical approach for in vivo, in situ verification of proton therapy. This article reviews the current status of proton therapy verification with PET imaging. The different data detecting systems (in-beam, in-room and off-line PET), calculation methods for the prediction of proton induced PET activity distributions...

  17. Diagnostic value of 18F-FDG PET and 11C-PIB PET on early stage posterior cortical atrophy

    Directory of Open Access Journals (Sweden)

    Shuai LIU

    2015-08-01

    Full Text Available Background  Posterior cortical atrophy (PCA is a kind of progressive neurodegenerative disease with cortical visual impairment as the first symptom. Because of rare clinical incidence, early onset age, special clinical symptoms and unobvious MRI abnormality, the definitive diagnosis of PCA is difficult. This study used 18F-fluoro-2-deoxy-D-glucose (18F-FDG PET and 11C-Pittsburgh compound B (11C-PIB PET for PCA patients with unobvious MRI abnormality, so as to discuss the value of PET in the early diagnosis of PCA.  Methods  Five patients diagnosed as PCA in our hospital between April 2012 and March 2015 were enrolled in this study. Cognitive function was measured by Mini-Mental State Examination (MMSE, Montreal Cognitive Assessment (MoCA, Activities of Daily Living (ADL and Clock Drawing Test (CDT. Brain MRI, 18F-FDG PET and 11C-PIB PET were performed to analyze glucose metabolism and perfusion of posterior cortex.  Results Neuropsychological tests revealed that the ability of writing, calculating, visuospatial and executive function of all these patients were impaired. Color vision tests showed abnormal results. MRI showed that the posterior atrophy (PA scores were 0-2 (average 1 on the left side and 0-1 (average 0.80 on the right side. The medial temporal atrophy (MTA scores were 1-3 (average 1.80 on the left side and 1-4 (average 2 on the right side. The ventricular enlargement (VE scores were 1-2 (average 1.80 on the left side and 1-2 (average 1.60 on the right side. 18F-FDG PET showed glucose metabolism decreased obviously on bilateral temporo-parieto-occipital cortex, precuneus and cingulate gyrus, and slightly on frontal lobes and subcortical structure. 11C-PIB PET showed radioactive 11C-PIB deposition on bilateral frontal, temporal, parietal and occipital cortex, and the outline of cerebellar cortex was clear.  Conclusions  For PCA patients whose parietal and occipital cortical atrophy is not obvious on MRI, 18F-FDG PET

  18. Combined PET/CT with iodine-124 in diagnosis of spread metastatic thyroid carcinoma: a case report

    International Nuclear Information System (INIS)

    Iodine-124 positron emission tomography (PET) is a useful 3D imaging technique for diagnosis and management of thyroid diseases. The difficulty in interpretation of the PET scans with highly selective tracers, such as iodine-124, is the lack of identifiable anatomical structures, so an accurate anatomical localization of foci presenting abnormal uptake is problematic. Consequently, a combined PET/CT scanner can resolve these difficulties by co-registering PET and CT data in a single session allowing a correlation of functional and morphologic imaging. A case is presented where iodine-124 produced by a clinical cyclotron and FDG were used to acquire images with a combined PET/CT scanner for clinical staging. On the basis of the PET/CT exams the treatment of the patient was modified. (orig.)

  19. The rise and fall of PET and PET/CT. A German perspective

    International Nuclear Information System (INIS)

    PET is being considered a diagnostic commodity in clinical practice worldwide and thus receives increasing attention by health insurances and governmental organizations. In Germany, however, neither PET nor PET/CT are subject to reimbursement. This renders clinical PET and PET/CT imaging a challenge both in general hospital environment and in private practice. This article describes briefly these challenges, which are not solely related to turf battles and associated costs. (orig.)

  20. Kinetic modeling in PET imaging of hypoxia

    DEFF Research Database (Denmark)

    Li, Fan; Jørgensen, Jesper Tranekjær; Hansen, Anders E;

    2014-01-01

    used for non-invasive mapping of tissue oxygenation in vivo and several hypoxia specific PET tracers have been developed. Evaluation of PET data in the clinic is commonly based on visual assessment together with semiquantitative measurements e.g. standard uptake value (SUV). However, dynamic PET...

  1. Pet care during preadolescence: developmental considerations.

    Science.gov (United States)

    Davis, J H

    1987-01-01

    This exploratory study investigated pet care in relation to psychosocial development during preadolescence. A group of male and female preadolescents (n = 22) at appropriate grade level for age completed a dog care responsibility inventory. The results revealed that preadolescents in general do not routinely care for pets. Mothers appear to assume most pet care tasks. PMID:3664972

  2. Saying Goodbye: Pet Loss and Its Implications

    Science.gov (United States)

    Duffey, Thelma

    2005-01-01

    Pets can be loyal, loving, and entertaining members of a family. Their deaths are generally experienced as painful losses by the people who love them, even though the grief experience is often culturally disenfranchised. In this manuscript, we discuss the role that pets can play in a person's life; the effects that pet loss can have on the people…

  3. 36 CFR 13.1234 - Pets.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Pets. 13.1234 Section 13.1234 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK... § 13.1234 Pets. Possessing a pet in the BCDA is prohibited....

  4. PET and SPECT in neurology

    Energy Technology Data Exchange (ETDEWEB)

    Dierckx, Rudi A.J.O. [Groningen University Medical Center (Netherlands). Dept. of Nuclear Medicine and Molecular Imaging; Ghent Univ. (Belgium). Dept. of Radiology and Nuclear Medicine; Vries, Erik F.J. de; Waarde, Aren van [Groningen University Medical Center (Netherlands). Dept. of Nuclear Medicine and Molecular Imaging; Otte, Andreas (ed.) [Univ. of Applied Sciences Offenburg (Germany). Faculty of Electrical Engineering and Information Technology

    2014-07-01

    PET and SPECT in Neurology highlights the combined expertise of renowned authors whose dedication to the investigation of neurological disorders through nuclear medicine technology has achieved international recognition. Classical neurodegenerative disorders are discussed as well as cerebrovascular disorders, brain tumors, epilepsy, head trauma, coma, sleeping disorders, and inflammatory and infectious diseases of the CNS. The latest results in nuclear brain imaging are detailed. Most chapters are written jointly by a clinical neurologist and a nuclear medicine specialist to ensure a multidisciplinary approach. This state-of-the-art compendium will be valuable to anybody in the field of neuroscience, from the neurologist and the radiologist/nuclear medicine specialist to the interested general practitioner and geriatrician. It is the second volume of a trilogy on PET and SPECT imaging in the neurosciences, the other volumes covering PET and SPECT in psychiatry and in neurobiological systems.

  5. Understanding advertising in pet nutrition.

    Science.gov (United States)

    Brown, R G

    1994-04-01

    Advertising is part of the effort to attract attention of consumers to products, in this case, pet foods. It is generally benign in its effect, but it can be misleading, although rarely deliberately so. It uses a specialized vocabulary, which must be mastered if one is to understand what is intended. For all of the expense and effort, advertising figures directly in relatively few decisions to purchase. Its main intention is to call our attention to a particular pet food and to give that product an image. If the pet food does not perform in the consumer's hands, then all of the advertising on earth will not be persuasive. On the other hand, if a product performs well, the word-of-mouth will be positive and that mode of advertising is one of the most effective. PMID:8076285

  6. Promoting the exotic pet practice.

    Science.gov (United States)

    Harris, Don J

    2005-09-01

    The marketing and promotion of an exotic pet veterinary practice allows the use of strategies that are not necessarily available in other veterinary disciplines. The advantage that an exotics practice enjoys is that it is able to capitalize not only on the unique nature of the species being attended but also on the specialized features of the hospital itself that make it specifically appropriate in caring for exotic pets. Before marketing, however, comes the responsibility that the practice live up to the claims made in promotional materials. A practice cannot ethically be presented as an "exotics" practice if it is nothing more than a dog and cat facility that is willing to attend to exotic pets. It is the competence of the veterinary staff and the appropriateness of the facility that determines the suitability of the practice for exotics management. PMID:16129354

  7. PET and SPECT in neurology

    International Nuclear Information System (INIS)

    PET and SPECT in Neurology highlights the combined expertise of renowned authors whose dedication to the investigation of neurological disorders through nuclear medicine technology has achieved international recognition. Classical neurodegenerative disorders are discussed as well as cerebrovascular disorders, brain tumors, epilepsy, head trauma, coma, sleeping disorders, and inflammatory and infectious diseases of the CNS. The latest results in nuclear brain imaging are detailed. Most chapters are written jointly by a clinical neurologist and a nuclear medicine specialist to ensure a multidisciplinary approach. This state-of-the-art compendium will be valuable to anybody in the field of neuroscience, from the neurologist and the radiologist/nuclear medicine specialist to the interested general practitioner and geriatrician. It is the second volume of a trilogy on PET and SPECT imaging in the neurosciences, the other volumes covering PET and SPECT in psychiatry and in neurobiological systems.

  8. Fluorine-18 labeled tracers for PET studies in the neurosciences

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Yu-Shin; Fowler, J.S.

    1995-12-31

    This chapter focuses on fluorine-18, the positron emitter with the longest half-life, the lowest positron energy and probably, the most challenging chemistry. The incorporation of F-18 into organic compounds presents many challenges, including: the need to synthesize and purify the compound within a 2--3 hour time frame; the limited number of labeled precursor molecules; the need to work on a microscale; and the need to produce radiotracers which are chemically and radiochemically pure, sterile and pyrogen-free, and suitable for intravenous injection. The PET method and F-18 labeling of organic molecules are described followed by highlights of the applications of F-18 labeled compounds in the neurosciences and neuropharmacology. It is important to emphasize the essential and pivotal role that organic synthesis has played in the progression of the PET field over the past twenty years from one in which only a handful of institutions possessed the instrumentation and staff to carry out research to the present-day situation where there are more than 200 PET centers worldwide. During this period PET has become an important scientific tool in the neurosciences, cardiology and oncology. It is important to point out that PET is by no means a mature field. The fact that a hundreds of different F-18 labeled compounds have been developed but only a few possess the necessary selectivity and sensitivity in vivo to track a specific biochemical process illustrates this and underscores a major difficulty in radiotracer development, namely the selection of priority structures for synthesis and the complexities of the interactions between chemical compounds and living systems. New developments in rapid organic synthesis are needed in order to investigate new molecular targets and to improve the quantitative nature of PET experiments.

  9. Fluorine-18 labeled tracers for PET studies in the neurosciences

    International Nuclear Information System (INIS)

    This chapter focuses on fluorine-18, the positron emitter with the longest half-life, the lowest positron energy and probably, the most challenging chemistry. The incorporation of F-18 into organic compounds presents many challenges, including: the need to synthesize and purify the compound within a 2--3 hour time frame; the limited number of labeled precursor molecules; the need to work on a microscale; and the need to produce radiotracers which are chemically and radiochemically pure, sterile and pyrogen-free, and suitable for intravenous injection. The PET method and F-18 labeling of organic molecules are described followed by highlights of the applications of F-18 labeled compounds in the neurosciences and neuropharmacology. It is important to emphasize the essential and pivotal role that organic synthesis has played in the progression of the PET field over the past twenty years from one in which only a handful of institutions possessed the instrumentation and staff to carry out research to the present-day situation where there are more than 200 PET centers worldwide. During this period PET has become an important scientific tool in the neurosciences, cardiology and oncology. It is important to point out that PET is by no means a mature field. The fact that a hundreds of different F-18 labeled compounds have been developed but only a few possess the necessary selectivity and sensitivity in vivo to track a specific biochemical process illustrates this and underscores a major difficulty in radiotracer development, namely the selection of priority structures for synthesis and the complexities of the interactions between chemical compounds and living systems. New developments in rapid organic synthesis are needed in order to investigate new molecular targets and to improve the quantitative nature of PET experiments

  10. Understanding advertising in pet nutrition.

    OpenAIRE

    Brown, R G

    1994-01-01

    Advertising is part of the effort to attract attention of consumers to products, in this case, pet foods. It is generally benign in its effect, but it can be misleading, although rarely deliberately so. It uses a specialized vocabulary, which must be mastered if one is to understand what is intended. For all of the expense and effort, advertising figures directly in relatively few decisions to purchase. Its main intention is to call our attention to a particular pet food and to give that prod...

  11. The Petit Rat (pet/pet), a New Semilethal Mutant Dwarf Rat with Thymic and Testicular Anomalies

    OpenAIRE

    Chiba, Junko; Suzuki, Katsushi; Suzuki, Hiroetsu

    2008-01-01

    The petit rat (pet/pet) is a recently discovered semilethal mutant dwarf. The neonatal pet/pet rats had a low body weight and small thymus and testis. During the first 3 d after birth, 50% of the male and 80% of the female pet/pet pups were lost or found dead. Surviving pet/pet rats showed marked retardation of postnatal growth, and their body weights were 41% (female rats) and 32% (male rats) of those of normal rats at the adult stage. The pet/pet rats exhibited proportional dwarfism, and th...

  12. A unified Fourier theory for time-of-flight PET data.

    Science.gov (United States)

    Li, Yusheng; Matej, Samuel; Metzler, Scott D

    2016-01-21

    Fully 3D time-of-flight (TOF) PET scanners offer the potential of previously unachievable image quality in clinical PET imaging. TOF measurements add another degree of redundancy for cylindrical PET scanners and make photon-limited TOF-PET imaging more robust than non-TOF PET imaging. The data space for 3D TOF-PET data is five-dimensional with two degrees of redundancy. Previously, consistency equations were used to characterize the redundancy of TOF-PET data. In this paper, we first derive two Fourier consistency equations and Fourier-John equation for 3D TOF PET based on the generalized projection-slice theorem; the three partial differential equations (PDEs) are the dual of the sinogram consistency equations and John's equation. We then solve the three PDEs using the method of characteristics. The two degrees of entangled redundancy of the TOF-PET data can be explicitly elicited and exploited by the solutions of the PDEs along the characteristic curves, which gives a complete understanding of the rich structure of the 3D x-ray transform with TOF measurement. Fourier rebinning equations and other mapping equations among different types of PET data are special cases of the general solutions. We also obtain new Fourier rebinning and consistency equations (FORCEs) from other special cases of the general solutions, and thus we obtain a complete scheme to convert among different types of PET data: 3D TOF, 3D non-TOF, 2D TOF and 2D non-TOF data. The new FORCEs can be used as new Fourier-based rebinning algorithms for TOF-PET data reduction, inverse rebinnings for designing fast projectors, or consistency conditions for estimating missing data. Further, we give a geometric interpretation of the general solutions--the two families of characteristic curves can be obtained by respectively changing the azimuthal and co-polar angles of the biorthogonal coordinates in Fourier space. We conclude the unified Fourier theory by showing that the Fourier consistency equations are

  13. Competitive advantage of PET/MRI

    International Nuclear Information System (INIS)

    Multimodality imaging has made great strides in the imaging evaluation of patients with a variety of diseases. Positron emission tomography/computed tomography (PET/CT) is now established as the imaging modality of choice in many clinical conditions, particularly in oncology. While the initial development of combined PET/magnetic resonance imaging (PET/MRI) was in the preclinical arena, hybrid PET/MR scanners are now available for clinical use. PET/MRI combines the unique features of MRI including excellent soft tissue contrast, diffusion-weighted imaging, dynamic contrast-enhanced imaging, fMRI and other specialized sequences as well as MR spectroscopy with the quantitative physiologic information that is provided by PET. Most evidence for the potential clinical utility of PET/MRI is based on studies performed with side-by-side comparison or software-fused MRI and PET images. Data on distinctive utility of hybrid PET/MRI are rapidly emerging. There are potential competitive advantages of PET/MRI over PET/CT. In general, PET/MRI may be preferred over PET/CT where the unique features of MRI provide more robust imaging evaluation in certain clinical settings. The exact role and potential utility of simultaneous data acquisition in specific research and clinical settings will need to be defined. It may be that simultaneous PET/MRI will be best suited for clinical situations that are disease-specific, organ-specific, related to diseases of the children or in those patients undergoing repeated imaging for whom cumulative radiation dose must be kept as low as reasonably achievable. PET/MRI also offers interesting opportunities for use of dual modality probes. Upon clear definition of clinical utility, other important and practical issues related to business operational model, clinical workflow and reimbursement will also be resolved

  14. PET and PET/CT in malignant melanoma

    International Nuclear Information System (INIS)

    The advantages that it has the PET/CT are: 1. It diminishes mainly positive false lesions. It identifies physiologic accumulate places. 2. It diminishes in smaller grade false negative. Small injuries. Injuries with low grade concentration. Injure on intense activity areas. 3. Precise anatomical localization of accumulate places. 4. Reduction of the acquisition time. (Author)

  15. Hybrid MR-PET in Neuroimaging.

    Science.gov (United States)

    Bisdas, S; Lá Fougere, C; Ernemann, U

    2015-10-01

    Hybrid magnetic resonance (MR)-positron emission tomography (MR-PET) is a novel technology with advantages over sequential MR and PET imaging, allowing maintain full individual diagnostic performance with negligible mutual interference between the two hardware settings. Obvious synergies between MR and PET in acquisition of anatomical, functional, and molecular information for neurological diseases into one single image pave the way for establishing clear clinical indications for hybrid MR-PET as well as addressing unmet neuroimaging needs in future clinics and research. Further developments in attenuation correction, quantification, workflow, and effective MR-PET data management might unfold the full potential of integrated multimodality imaging. PMID:26227618

  16. FDG-PET response-adapted therapy

    DEFF Research Database (Denmark)

    Hutchings, Martin

    2014-01-01

    Fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) is the most accurate tool for staging, treatment monitoring, and response evaluation in Hodgkin lymphoma (HL). Early determination of treatment sensitivity by FDG-PET is the best tool to guide individualized......, response-adapted treatment. Several ongoing or recently completed trials have investigated the use of FDG-PET/CT for early response-adapted HL therapy. The results are encouraging, but the data are immature, and PET response-adapted HL therapy is discouraged outside the setting of clinical trials. PET...

  17. Development of PET/MRI with insertable PET for simultaneous PET and MR imaging of human brain

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jin Ho; Choi, Yong, E-mail: ychoi.image@gmail.com; Jung, Jiwoong; Kim, Sangsu; Lim, Hyun Keong; Im, Ki Chun [Department of Electronic Engineering, Sogang University, 35 Baekbeom-ro, Mapo-gu, Seoul 121-742 (Korea, Republic of); Oh, Chang Hyun; Park, Hyun-wook [Department of Electrical Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Kim, Kyung Min; Kim, Jong Guk [Korea Institute of Radiological and Medical Science, 75 Nowon-ro, Nowon-gu, Seoul 139-709 (Korea, Republic of)

    2015-05-15

    Purpose: The purpose of this study was to develop a dual-modality positron emission tomography (PET)/magnetic resonance imaging (MRI) with insertable PET for simultaneous PET and MR imaging of the human brain. Methods: The PET detector block was composed of a 4 × 4 matrix of detector modules, each consisting of a 4 × 4 array LYSO coupled to a 4 × 4 Geiger-mode avalanche photodiode (GAPD) array. The PET insert consisted of 18 detector blocks, circularly mounted on a custom-made plastic base to form a ring with an inner diameter of 390 mm and axial length of 60 mm. The PET gantry was shielded with gold-plated conductive fabric tapes with a thickness of 0.1 mm. The charge signals of PET detector transferred via 4 m long flat cables were fed into the position decoder circuit. The flat cables were shielded with a mesh-type aluminum sheet with a thickness of 0.24 mm. The position decoder circuit and field programmable gate array-embedded DAQ modules were enclosed in an aluminum box with a thickness of 10 mm and located at the rear of the MR bore inside the MRI room. A 3-T human MRI system with a Larmor frequency of 123.7 MHz and inner bore diameter of 60 cm was used as the PET/MRI hybrid system. A custom-made radio frequency (RF) coil with an inner diameter of 25 cm was fabricated. The PET was positioned between gradient and the RF coils. PET performance was measured outside and inside the MRI scanner using echo planar imaging, spin echo, turbo spin echo, and gradient echo sequences. MRI performance was also evaluated with and without the PET insert. The stability of the newly developed PET insert was evaluated and simultaneous PET and MR images of a brain phantom were acquired. Results: No significant degradation of the PET performance caused by MR was observed when the PET was operated using various MR imaging sequences. The signal-to-noise ratio of MR images was slightly degraded due to the PET insert installed inside the MR bore while the homogeneity was

  18. Development of PET/MRI with insertable PET for simultaneous PET and MR imaging of human brain

    International Nuclear Information System (INIS)

    Purpose: The purpose of this study was to develop a dual-modality positron emission tomography (PET)/magnetic resonance imaging (MRI) with insertable PET for simultaneous PET and MR imaging of the human brain. Methods: The PET detector block was composed of a 4 × 4 matrix of detector modules, each consisting of a 4 × 4 array LYSO coupled to a 4 × 4 Geiger-mode avalanche photodiode (GAPD) array. The PET insert consisted of 18 detector blocks, circularly mounted on a custom-made plastic base to form a ring with an inner diameter of 390 mm and axial length of 60 mm. The PET gantry was shielded with gold-plated conductive fabric tapes with a thickness of 0.1 mm. The charge signals of PET detector transferred via 4 m long flat cables were fed into the position decoder circuit. The flat cables were shielded with a mesh-type aluminum sheet with a thickness of 0.24 mm. The position decoder circuit and field programmable gate array-embedded DAQ modules were enclosed in an aluminum box with a thickness of 10 mm and located at the rear of the MR bore inside the MRI room. A 3-T human MRI system with a Larmor frequency of 123.7 MHz and inner bore diameter of 60 cm was used as the PET/MRI hybrid system. A custom-made radio frequency (RF) coil with an inner diameter of 25 cm was fabricated. The PET was positioned between gradient and the RF coils. PET performance was measured outside and inside the MRI scanner using echo planar imaging, spin echo, turbo spin echo, and gradient echo sequences. MRI performance was also evaluated with and without the PET insert. The stability of the newly developed PET insert was evaluated and simultaneous PET and MR images of a brain phantom were acquired. Results: No significant degradation of the PET performance caused by MR was observed when the PET was operated using various MR imaging sequences. The signal-to-noise ratio of MR images was slightly degraded due to the PET insert installed inside the MR bore while the homogeneity was

  19. Role of 68Ga-DOTANOC PET/CT in the dedifferentiated thyroid cancer and comparison with 18F-FDG PET/CT: preliminary data

    International Nuclear Information System (INIS)

    Full text: Aim: To evaluate the role of 68Ga-DOTANOC PET/CT in whole body radioiodine scan negative recurrent differentiated thyroid cancer and comparison with 18F-FDG PET/CT. Materials and Methods: In this prospective study 32 patients of differentiated thyroid cancer presenting with increased Tg value and having no abnormal concentration on whole body radioiodine scan were included. Patients underwent both 68Ga-DOTANOC PET/CT and 18F-FDG PET/CT in random order within 4 weeks time interval. Patient showing lesion(s) on either of scan was considered as recurrent disease positive and substantiated by structural imaging. Tumor lesions were categorised according to four sites-local, nodal, pulmonary and skeletal for comparison of detection rate between two functional modalities. Total number of lesions was defined as sum of number of lesions detected by at least one of the two scans. The analysis is performed on the basis of patient data, and as well as lesion wise. Results: Positive recurrent disease was observed in 24/32 (75%) on either of the scans. In 13/32 (40%) of these patients both imaging modalities detected metastatic disease. In 8/32 (26%) patients disease was detected only by 18F-FDG PET/CT and in 3/32 (9%) patients only 68Ga-DOTANOC PET/CT diagnosed disease. 18F-FDG PET/CT and 68Ga-DOTANOC PET/CT showed moderate agreement (k=0.313, P-value=0.03) in detecting disease on patient basis which is statistically significant. Total number of positive lesions detected on either of the modality was 73. 18F-FDG PET/CT showed 64/73 (87%) lesions and 68Ga-DOTANOC PET/CT detected 31/73 (42%) lesions. 18F-FDG PET/CT and 68Ga-DOTANOC PET/CT showed 22/73 (30%) concordant lesions. Lesions detected only by 18F-FDG PET/CT were 33/73 (45%) and only by 68Ga-DOTANOC PET/CT 9/73 (12%). Location-wise tumor lesion detection showed fair agreement between two modalities for local (k=0.720) and skeletal (k=0.6) disease. However, detection for nodal (k=0.32) and pulmonary (k=0

  20. The MiniPET: a didactic PET system

    Science.gov (United States)

    Pedro, R.; Silva, J.; Gurriana, L.; Silva, J. M.; Maio, A.; Soares Augusto, J.

    2013-03-01

    The MiniPET project aims to design and build a small PET system. It consists of two 4 × 4 matrices of 16 LYSO scintillator crystals and two PMTs with 16 channels resulting in a low cost system with the essential functionality of a clinical PET instrument. It is designed to illustrate the physics of the PET technique and to provide a didactic platform for the training of students and nuclear imaging professionals as well as for scientific outreach. The PET modules can be configured to test for the coincidence of 511 keV gamma rays. The model has a flexible mechanical setup [1] and can simulate 14 diferent ring geometries, from a configuration with as few as 18 detectors per ring (ring radius phi=51 mm), up to a geometry with 70 detectors per ring (phi=200 mm). A second version of the electronic system [2] allowed measurement and recording of the energy deposited in 4 detector channels by photons from a 137Cs radioactive source and by photons resulting of the annihilation of positrons from a 22Na radioactive source. These energy spectra are used for detector performance studies, as well as angular dependency studies. In this paper, the mechanical setup, the front-end high-speed analog electronics, the digital acquisition and control electronics implemented in a FPGA, as well as the data-transfer interface between the FPGA board and a host PC are described. Recent preliminary results obtained with the 4 active channels in the prototype are also presented.