WorldWideScience

Sample records for chest high-field magnetic

  1. Lung disease assessment in primary ciliary dyskinesia: a comparison between chest high-field magnetic resonance imaging and high-resolution computed tomography findings

    Directory of Open Access Journals (Sweden)

    Iacotucci Paola

    2009-08-01

    Full Text Available Abstract Background Primary ciliary dyskinesia (PCD is associated with pulmonary involvement that requires periodical assessment. Chest high-resolution computed tomography (HRCT has become the method of choice to evaluate chronic lung disease, but entails exposure to ionizing radiation. Magnetic resonance imaging (MRI has been proposed as a potential radiation-free technique in several chest disorders. Aim of our study is to evaluate whether high-field MRI is as effective as HRCT in identifying PCD pulmonary abnormalities. We also analyzed the relationships between the severity and extension of lung disease, and functional data. Methods Thirteen PCD patients (8 children/5 adults; median age, 15.2 yrs underwent chest HRCT and high-field 3T MRI, spirometry, and deep throat or sputum culture. Images were scored using a modified version of the Helbich system. Results HRCT and MRI total scores were 12 (range, 6–20 and 12 (range, 5–17, respectively. Agreement between HRCT and MRI scores was good or excellent (r > 0.8. HRCT and MRI total scores were significantly related to forced vital capacity (r = -0.5, p = 0.05; and r = -0.7, p = 0.009, respectively and forced expiratory volume at 1 second (r = -0.6, p = 0.03; and r = -0.7, p = 0.009, respectively. Conclusion Chest high-field 3T MRI appears to be as effective as HRCT in assessing the extent and severity of lung abnormalities in PCD. MRI scores might be used for longitudinal assessment and be an outcome surrogate in future studies.

  2. KEK effort for high field magnets

    CERN Document Server

    Nakamoto, T

    2011-01-01

    KEK has emphasized efforts to develop the RHQNb3Al superconductor and a sub-scale magnet reaching 13 T towards the HL-LHC upgrade in last years. In addition, relevant R&D regarding radiation resistance has been carried out. For higher field magnets beyond 15 T, HTS in combination with A15 superconductors should be one of baseline materials. However, all these superconductors are very sensitive to stress and strain and thorough understanding of behaviour is truly desired for realization of high field magnets. KEK has launched a new research subject on stress/strain sensitivity of HTS and A15 superconductors in collaboration with the neutron diffraction facility at J-PARC and High Field Laboratory in Tohoku University. Present activity for high field magnets at KEK is reported.

  3. Strain sensors for high field pulse magnets

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Christian [Los Alamos National Laboratory; Zheng, Yan [Los Alamos National Laboratory; Easton, Daniel [Los Alamos National Laboratory; Farinholt, Kevin M [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory

    2009-01-01

    In this paper we present an investigation into several strain sensing technologies that are being considered to monitor mechanical deformation within the steel reinforcement shells used in high field pulsed magnets. Such systems generally operate at cryogenic temperatures to mitigate heating issues that are inherent in the coils of nondestructive, high field pulsed magnets. The objective of this preliminary study is to characterize the performance of various strain sensing technologies at liquid nitrogen temperatures (-196 C). Four sensor types are considered in this investigation: fiber Bragg gratings (FBG), resistive foil strain gauges (RFSG), piezoelectric polymers (PVDF), and piezoceramics (PZT). Three operational conditions are considered for each sensor: bond integrity, sensitivity as a function of temperature, and thermal cycling effects. Several experiments were conducted as part of this study, investigating adhesion with various substrate materials (stainless steel, aluminum, and carbon fiber), sensitivity to static (FBG and RFSG) and dynamic (RFSG, PVDF and PZT) load conditions, and sensor diagnostics using PZT sensors. This work has been conducted in collaboration with the National High Magnetic Field Laboratory (NHMFL), and the results of this study will be used to identify the set of sensing technologies that would be best suited for integration within high field pulsed magnets at the NHMFL facility.

  4. Stability of high field superconducting dipole magnets

    International Nuclear Information System (INIS)

    Superconducting dipole magnets of the window-frame type were constructed and operated successfully at Brookhaven National Laboratory. Examples of this type of magnet are the 6 T ''Model T'' magnet, and the 4 T 80 superconducting bending magnet. The latter magnet operated reliably since October 1973 as part of the proton beam transport to the north experimental area at the BNL AGS with intensities of typically 8 x 1012 protons at 28.5 GeV/c passing through the magnet in a curved trajectory with the proton beam center only 2.0 cm from the beam pipe at both ends and the middle of each of the two units comprising the magnet. The energy in the beam is approximately 40 kJ per 3 μsec pulse. Targets were inserted in the beam at locations 2 m and 5.6 m upstream of the first magnet unit to observe the effects of radiation heating. The 80 magnet demonstrated ultrastability, surviving 3 μsec thermal pulses delivering up to 1 kJ into the cold magnet at repetition periods as short as 1.3 sec

  5. High Field Pulse Magnets with New Materials

    Science.gov (United States)

    Li, L.; Lesch, B.; Cochran, V. G.; Eyssa, Y.; Tozer, S.; Mielke, C. H.; Rickel, D.; van Sciver, S. W.; Schneider-Muntau, H. J.

    2004-11-01

    High performance pulse magnets using the combination of CuNb conductor and Zylon fiber composite reinforcement with bore sizes of 24, 15 and 10 mm have been designed, manufactured and tested to destruction. The magnets successfully reached the peak fields of 64, 70 and 77.8 T respectively with no destruction. Failures occurred near the end flanges at the layer. The magnet design, manufacturing and testing, and the mode of the failure are described and analyzed.

  6. High Field Magnetization of Tb Single Crystals

    DEFF Research Database (Denmark)

    Roeland, L. W.; Cock, G. J.; Lindgård, Per-Anker

    1975-01-01

    The magnetization of Tb single crystals was measured in magnetic fields to 34T along the hard direction at temperature of 1.8, 4.2, 65.5 and 77K, and along with easy direction at 4.2 and 77K. The data are compared with the results of a self-consistent spin wave calculation using a phenomenologica...

  7. High-Field Accelerator Magnets Beyond LHC

    CERN Document Server

    Devred, Arnaud

    2003-01-01

    The LHC magnet R&D Program has shown that the limit of NbTi technology at 1.8 K was in the range 10 to 10.5 T. Hence, to go beyond the 10-T threshold, it is necessary to change of superconducting material. Given the state of the art in HTS, the only serious candidate is Nb3Sn. A series of dipole magnet models built at Twente University and LBNL and a vigorous program underway at FNAL have demonstrated the feasibility of Nb3Sn magnet technology. The next step is to bring this technology to maturity, which requires further conductor and conductor insulation development and a simplification of manufacturing processes. After outlining a roadmap to address outstanding issues, we evoke the US proposal for a second generation of LHC Insertion Region (IR) magnets and the Next European Dipole (NED) initiative promoted by the European Steering Group on Accelerator R&D (ESGARD).

  8. A high field magnet design for a future hadron collider

    CERN Document Server

    Gupta, R; Dietderich, D R; Gourlay, S A; Millos, G; McInturff, A D; Scanlan, R M; Ramberger, S; Russenschuck, Stephan

    1999-01-01

    US high energy physics community is exploring the possibilities of building a Very Large Hadron Collider (VLHC) after the completion of LHC. This paper presents a high field magnet design option based on Nb/sub 3/Sn technology. A preliminary magnetic and mechanical design of a 14-16 T, 2-in-1 dipole based on the "common coil design" approach is presented. The computer code ROXIE has been upgraded to perform the field quality optimization of magnets based on the racetrack coil geometry. A magnet R&D program to investigate the issues related to high field magnet designs is also outlined. (10 refs).

  9. Radiofrequency solutions in clinical high field magnetic resonance

    NARCIS (Netherlands)

    Andreychenko, A.

    2013-01-01

    Magnetic resonance imaging (MRI) and spectroscopy (MRS) benefit from the sensitivity gain at high field (≥7T). However, high field brings also certain challenges associated with growing frequency and spectral dispersion. Frequency growth results in degraded performance of large volume radiofrequency

  10. Ultra-high-field magnetic resonance: Why and when?

    OpenAIRE

    Moser, Ewald

    2010-01-01

    This paper briefly summarizes the development of magnetic resonance imaging and spectroscopy in medicine. Aspects of magnetic resonancephysics and -technology relevant at ultra-high magnetic fields as well as current limitations are highlighted. Based on the first promising studies, potential clinical applications at 7 Tesla are suggested. Other aims are to stimulate awareness of the potential of ultra-high field magnetic resonance and to stimulate active participation in much needed basic or...

  11. The high field superconducting magnet program at LLNL: Annual report

    International Nuclear Information System (INIS)

    In FY 86 the program continued along several interrelated thrust areas. These thrust areas have been broadly labeled as follows: (1) Superconductor Research and Technology; (2) Magnet Systems Materials Technology; (3) Magnet Systems Design Technology; (4) High Field Test Facility; and (5) Technology Transfer

  12. Design of racetrack coils for high-field dipole magnets

    CERN Document Server

    Sabbi, G L; Gourlay, S A; Hafalia, R R; Jackson, A; Lietzke, A F; McInturff, A D; Scanlan, R M

    2001-01-01

    The magnet group at LBNL is in the process of developing high-field accelerator magnets for use in future colliders. One of the primary challenges is to provide a design which is cost-effective and simple to manufacture, at the same time resulting in good training performance and field quality adequate for accelerator operation. Studies have focused on a racetrack geometry that has the virtues of simplicity and conductor compatibility. The results have been applied to the design of a series of prototype high-field magnets based on Nb /sub 3/Sn conductor. (13 refs).

  13. Ultra-high-field magnets for future hadron colliders

    International Nuclear Information System (INIS)

    Several new concepts in magnetic design and coil fabrication are being incorporated into designs for ultra-high field collider magnets: a 16 Tesla block-coil dual dipole, also using Nb3Sn cable, featuring simple pancake coil construction and face-loaded prestress geometry; a 330 T/m block-coil quadrupole; and a ∼ 20 Tesla pipe-geometry dual dipole, using A15 or BSCCO tape. Field design and fabrication issues are discussed for each magnet

  14. Mechanical design of a high field common coil magnet

    CERN Document Server

    Caspi, S; Dietderich, D R; Gourlay, S A; Gupta, R; McInturff, A; Millos, G; Scanlan, R M

    1999-01-01

    A common coil design for high field 2-in-1 accelerator magnets has been previously presented as a "conductor-friendly" option for high field magnets applicable for a Very Large Hadron Collider. This paper presents the mechanical design for a 14 tesla 2-in-1 dipole based on the common coil design approach. The magnet will use a high current density Nb/sub 3/Sn conductor. The design addresses mechanical issues particular to the common coil geometry: horizontal support against coil edges, vertical preload on coil faces, end loading and support, and coil stresses and strains. The magnet is the second in a series of racetrack coil magnets that will provide experimental verification of the common coil design approach. (9 refs).

  15. On the origin of high-field magnetic white dwarfs

    CERN Document Server

    García-Berro, E; Lorén-Aguilar, P; Aznar-Siguán, G; Camacho, J; Külebi, B; Isern, J; Althaus, L G; Córsico, A H

    2012-01-01

    High-field magnetic white dwarfs have been long suspected to be the result of stellar mergers. However, the nature of the coalescing stars and the precise mechanism that produces the magnetic field are still unknown. Here we show that the hot, convective, differentially rotating corona present in the outer layers of the remnant of the merger of two degenerate cores is able to produce magnetic fields of the required strength that do not decay for long timescales. We also show, using an state-of-the-art Monte Carlo simulator, that the expected number of high-field magnetic white dwarfs produced in this way is consistent with that found in the solar neighborhood.

  16. Homogenous BSCCO-2212 Round Wires for Very High Field Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Scott Campbell

    2012-06-30

    The performance demands on modern particle accelerators generate a relentless push towards higher field magnets. In turn, advanced high field magnet development places increased demands on superconducting materials. Nb3Sn conductors have been used to achieve 16 T in a prototype dipole magnet and are thought to have the capability for {approx}18 T for accelerator magnets (primarily dipoles but also higher order multipole magnets). However there have been suggestions and proposals for such magnets higher than 20 T. The High Energy Physics Community (HEP) has identified important new physics opportunities that are enabled by extremely high field magnets: 20 to 50 T solenoids for muon cooling in a muon collider (impact: understanding of neutrinos and dark matter); and 20+ T dipoles and quadrupoles for high energy hadron colliders (impact: discovery reach far beyond present). This proposal addresses the latest SBIR solicitation that calls for grant applications that seek to develop new or improved superconducting wire technologies for magnets that operate at a minimum of 12 Tesla (T) field, with increases up to 15 to 20 T sought in the near future (three to five years). The long-term development of accelerator magnets with fields greater than 20 T will require superconducting wires having significantly better high-field properties than those possessed by current Nb{sub 3}Sn or other A15 based wires. Given the existing materials science base for Bi-2212 wire processing, we believe that Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub y} (Bi-2212) round wires can be produced in km-long piece lengths with properties suitable to meet both the near term and long term needs of the HEP community. The key advance will be the translation of this materials science base into a robust, high-yield wire technology. While the processing and application of A15 materials have advanced to a much higher level than those of the copper oxide-based, high T{sub c} (HTS) counterparts, the HTS materials have

  17. Stepped Impedance Resonators for High Field Magnetic Resonance Imaging

    OpenAIRE

    Akgun, Can E.; DelaBarre, Lance; Yoo, Hyoungsuk; Sohn, Sung-Min; Snyder, Carl J.; Adriany, Gregor; Ugurbil, Kamil; Gopinath, Anand; Vaughan, J. Thomas

    2014-01-01

    Multi-element volume radio-frequency (RF) coils are an integral aspect of the growing field of high field magnetic resonance imaging (MRI). In these systems, a popular volume coil of choice has become the transverse electromagnetic (TEM) multi-element transceiver coil consisting of microstrip resonators. In this paper, to further advance this design approach, a new microstrip resonator strategy in which the transmission line is segmented into alternating impedance sections referred to as step...

  18. Homogenous BSCCO-2212 Round Wires for Very High Field Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Scott Campbell

    2012-06-30

    The performance demands on modern particle accelerators generate a relentless push towards higher field magnets. In turn, advanced high field magnet development places increased demands on superconducting materials. Nb3Sn conductors have been used to achieve 16 T in a prototype dipole magnet and are thought to have the capability for {approx}18 T for accelerator magnets (primarily dipoles but also higher order multipole magnets). However there have been suggestions and proposals for such magnets higher than 20 T. The High Energy Physics Community (HEP) has identified important new physics opportunities that are enabled by extremely high field magnets: 20 to 50 T solenoids for muon cooling in a muon collider (impact: understanding of neutrinos and dark matter); and 20+ T dipoles and quadrupoles for high energy hadron colliders (impact: discovery reach far beyond present). This proposal addresses the latest SBIR solicitation that calls for grant applications that seek to develop new or improved superconducting wire technologies for magnets that operate at a minimum of 12 Tesla (T) field, with increases up to 15 to 20 T sought in the near future (three to five years). The long-term development of accelerator magnets with fields greater than 20 T will require superconducting wires having significantly better high-field properties than those possessed by current Nb{sub 3}Sn or other A15 based wires. Given the existing materials science base for Bi-2212 wire processing, we believe that Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub y} (Bi-2212) round wires can be produced in km-long piece lengths with properties suitable to meet both the near term and long term needs of the HEP community. The key advance will be the translation of this materials science base into a robust, high-yield wire technology. While the processing and application of A15 materials have advanced to a much higher level than those of the copper oxide-based, high T{sub c} (HTS) counterparts, the HTS materials have

  19. High-field small animal magnetic resonance oncology studies

    Science.gov (United States)

    Bokacheva, Louisa; Ackerstaff, Ellen; LeKaye, H. Carl; Zakian, Kristen; Koutcher, Jason A.

    2014-01-01

    This review focuses on the applications of high magnetic field magnetic resonance imaging (MRI) and spectroscopy (MRS) to cancer studies in small animals. High-field MRI can provide information about tumor physiology, the microenvironment, metabolism, vascularity and cellularity. Such studies are invaluable for understanding tumor growth and proliferation, response to treatment and drug development. The MR techniques reviewed here include 1H, 31P, chemical exchange saturation transfer imaging and hyperpolarized 13C MRS as well as diffusion-weighted, blood oxygen level dependent contrast imaging and dynamic contrast-enhanced MRI. These methods have been proven effective in animal studies and are highly relevant to human clinical studies.

  20. Micromagnetic simulation for high field sensors with perpendicular magnetizations

    Institute of Scientific and Technical Information of China (English)

    Jin Wei; Liu Yao-Wen

    2007-01-01

    In this paper, we present a micromagnetic design for high field sensors. The hard layer of the sensors is L10-FePt which is magnetized perpendicularly to film plane and the sense layer is NiFe which is magnetized in the film plane. The magnetization configurations of the hard and sense layers at different external magnetic fields have been simulated. In micromagnetic simulation, the sense field up to one tesla can be reached by using this sensor. We find that whether the sensor has a symmetric or an asymmetric field-sensing window is determined by the coercive field of the hard layer and the demagnetizing field of the sense layer.

  1. Nb$_{3}$Al high field accelerator magnet R&D

    CERN Document Server

    Sasaki, K; Tsuchiya, K; Terashima, A; Yamamoto, A; Rossi, L; Verweij, A; Oberli, L R; Kikuchi, A; Takeuchi, T; Sabbi, G L; Caspi, S; Ferracin, P; Felice, H; Hannaford, R; Hafalia, R; Yamada, R; Barzi, E; Zlobin, A

    2009-01-01

    KEK has been developing the Nb3Al strand and cable for a high field accelerator magnet in collaboration with NIMS for many years. And also the development of subscale magnet has been started practically since last year. KEK has studied on the effect of number of filaments and matrix ratio on non-Cu Jc for last two years and also developed continuous Cu electro-plating apparatus. NIMS has fabricated the trial Rutherford cable with 27 strands successfully in collaboration with Fermi lab. And also doublelayer common coil has been fabricated and tested successfully. The magnetic and mechanical design of 15 T subscale magnet has been started practically since last year, and the preparation of drawings and tools is ongoing in parallel.

  2. Chest magnetic resonance imaging: a protocol suggestion

    Directory of Open Access Journals (Sweden)

    Bruno Hochhegger

    2015-12-01

    Full Text Available Abstract In the recent years, with the development of ultrafast sequences, magnetic resonance imaging (MRI has been established as a valuable diagnostic modality in body imaging. Because of improvements in speed and image quality, MRI is now ready for routine clinical use also in the study of pulmonary diseases. The main advantage of MRI of the lungs is its unique combination of morphological and functional assessment in a single imaging session. In this article, the authors review most technical aspects and suggest a protocol for performing chest MRI. The authors also describe the three major clinical indications for MRI of the lungs: staging of lung tumors; evaluation of pulmonary vascular diseases; and investigation of pulmonary abnormalities in patients who should not be exposed to radiation.

  3. Magnetic resonance imaging and spectroscopy at ultra high fields

    Energy Technology Data Exchange (ETDEWEB)

    Neuberger, Thomas

    2009-06-23

    The goal of the work presented in this thesis was to explore the possibilities and limitations of MRI / MRS using an ultra high field of 17.6 tesla. A broad range of specific applications and MR methods, from MRI to MRSI and MRS were investigated. The main foci were on sodium magnetic resonance spectroscopic imaging of rodents, magnetic resonance spectroscopy of the mouse brain, and the detection of small amounts of iron labeled stem cells in the rat brain using MRI Sodium spectroscopic imaging was explored since it benefits tremendously from the high magnetic field. Due to the intrinsically low signal in vivo, originating from the low concentrations and short transverse relaxation times, only limited results have been achieved by other researchers until now. Results in the literature include studies conducted on large animals such as dogs to animals as small as rats. No studies performed on mice have been reported, despite the fact that the mouse is the most important laboratory animal due to the ready availability of transgenic strains. Hence, this study concentrated on sodium MRSI of small rodents, mostly mice (brain, heart, and kidney), and in the case of the brain on young rats. The second part of this work concentrated on proton magnetic resonance spectroscopy of the rodent brain. Due to the high magnetic field strength not only the increasing signal but also the extended spectral resolution was advantageous for such kind of studies. The difficulties/limitations of ultra high field MRS were also investigated. In the last part of the presented work detection limits of iron labeled stem cells in vivo using magnetic resonance imaging were explored. The studies provided very useful benchmarks for future researchers in terms of the number of labeled stem cells that are required for high-field MRI studies. Overall this work has shown many of the benefits and the areas that need special attention of ultra high fields in MR. Three topics in MRI, MRS and MRSI were

  4. Magnetic resonance imaging and spectroscopy at ultra high fields

    International Nuclear Information System (INIS)

    The goal of the work presented in this thesis was to explore the possibilities and limitations of MRI / MRS using an ultra high field of 17.6 tesla. A broad range of specific applications and MR methods, from MRI to MRSI and MRS were investigated. The main foci were on sodium magnetic resonance spectroscopic imaging of rodents, magnetic resonance spectroscopy of the mouse brain, and the detection of small amounts of iron labeled stem cells in the rat brain using MRI Sodium spectroscopic imaging was explored since it benefits tremendously from the high magnetic field. Due to the intrinsically low signal in vivo, originating from the low concentrations and short transverse relaxation times, only limited results have been achieved by other researchers until now. Results in the literature include studies conducted on large animals such as dogs to animals as small as rats. No studies performed on mice have been reported, despite the fact that the mouse is the most important laboratory animal due to the ready availability of transgenic strains. Hence, this study concentrated on sodium MRSI of small rodents, mostly mice (brain, heart, and kidney), and in the case of the brain on young rats. The second part of this work concentrated on proton magnetic resonance spectroscopy of the rodent brain. Due to the high magnetic field strength not only the increasing signal but also the extended spectral resolution was advantageous for such kind of studies. The difficulties/limitations of ultra high field MRS were also investigated. In the last part of the presented work detection limits of iron labeled stem cells in vivo using magnetic resonance imaging were explored. The studies provided very useful benchmarks for future researchers in terms of the number of labeled stem cells that are required for high-field MRI studies. Overall this work has shown many of the benefits and the areas that need special attention of ultra high fields in MR. Three topics in MRI, MRS and MRSI were

  5. High-field magnetization of dilute rare earths in yttrium

    DEFF Research Database (Denmark)

    Touborg, P.; Høg, J.; Cock, G. J.;

    1974-01-01

    Magnetization measurements have been performed on single crystals of Y containing small amounts of Tb, Dy, or Er at 4.2 K in fields up to 295 × 105 A/m (370 kOe). Crystal-field and molecular-field parameters obtained from measurements of the initial susceptibility versus temperature give a satisf......Magnetization measurements have been performed on single crystals of Y containing small amounts of Tb, Dy, or Er at 4.2 K in fields up to 295 × 105 A/m (370 kOe). Crystal-field and molecular-field parameters obtained from measurements of the initial susceptibility versus temperature give...... a satisfactory quantitative account of the high-field magnetization. This includes characteristic features due to the crossing and mixing of crystal-field levels....

  6. Ultra-high field magnets for whole-body MRI

    Science.gov (United States)

    Warner, Rory

    2016-09-01

    For whole-body MRI, an ultra-high field (UHF) magnet is currently defined as a system operating at 7 T or above. Over 70 UHF magnets have been built, all with the same technical approach originally developed by Magnex Scientific Ltd. The preferred coil configuration is a compensated solenoid. In this case, the majority of the field is generated by a simple long solenoid that stretches the entire length of the magnet. Additional coils are wound on a separate former outside the main windings with the purpose of balancing the homogeneity. Most of the magnets currently in operation are passively shielded systems where the magnet is surrounded by a steel box of 200-870 tonnes of carbon steel. More recently actively shielded magnets have been built for operation at 7 T; in this case the stray field is controlled by with reverse turns wound on a separate former outside the primary coils. Protection against quench damage is much more complex with an actively shielded magnet design due to the requirement to prevent the stray field from increasing during a quench. In the case of the 7 T 900 magnet this controlled by combining some of the screening coils into each section of the protection circuit. Correction of the field variations caused by manufacturing tolerances and environmental effects are made with a combination of superconducting shims and passive shims. Modern UHF magnets operate in zero boil-off mode with the use of cryocoolers with cooling capacity at 4.2 K. Although there are no cryogen costs associated with normal operation UHF magnets require a significant volume (10 000-20 000 l) of liquid helium for the cool-down. Liquid helium is expensive therefore new methods of cool-down using high-power cryocoolers are being implemented to reduce the requirement.

  7. Developments at the High Field Magnet Laboratory in Nijmegen

    Science.gov (United States)

    Perenboom, J. A. A. J.; Maan, J. C.; van Breukelen, M. R.; Wiegers, S. A. J.; den Ouden, A.; Wulffers, C. A.; van der Zande, W. J.; Jongma, R. T.; van der Meer, A. F. G.; Redlich, B.

    2013-03-01

    The High Field Magnet Laboratory at the Radboud University Nijmegen is rapidly expanding its capabilities. The developments encompass both organizational changes and new possibilities for research. The organization of the HFML was strengthened as a consequence of stronger participation of the Foundation for Fundamental Research on Matter (FOM), and an increase of the core-funding. This change makes that HFML is now considered on a national level as large research facility that operates at an international scale. At the same time work is underway to build new and powerful magnets, and provide electromagnetic radiation for magneto-spectroscopic studies. Electromagnetic radiation in the infrared and far-infrared spectrum will soon be available in the HFML with wavelengths between 3 μm and 1.5 mm, produced by the `FELIX' facility, comprising the long-wavelength free electron laser `FLARE' that in September 2011 produced its first light and the free electron lasers that have been moved from Rijnhuizen to Nijmegen. In magnet technology great strides are made to make magnets available for the user community with unprecedented performance: late in 2012 we hope to commission a new all-resistive magnet system that will generate a steady magnetic field as high as 38 T, by fully exploiting the maximum power of the installation, i.e. 20 MW, and using all available improvements in the design and construction of `Florida-Bitter' resistive magnets. We are also well underway with the design of a 45 T hybrid magnet system, using Nb3Sn superconductors and wind-and-react Cable-in-Conduit technology.

  8. Improved capacitive stress transducers for high-field superconducting magnets

    Science.gov (United States)

    Benson, Christopher Pete; Holik, Eddie Frank, III; Jaisle, Andrew; McInturff, A.; McIntyre, P.

    2012-06-01

    High-field (12-18 Tesla) superconducting magnets are required to enable an increase in the energy of future colliders. Such field strength requires the use of Nb3Sn superconductor, which has limited tolerance for compressive and shear strain. A strategy for stress management has been developed at Texas A&M University and is being implemented in TAMU3, a short-model 14 Tesla stress-managed Nb3Sn block dipole. The strategy includes the use of laminar capacitive stress transducers to monitor the stresses within the coil package. We have developed fabrication techniques and fixtures, which improve the reproducibility of the transducer response both at room temperature and during cryogenic operation. This is a report of the status of transducer development.

  9. High field nuclear magnetic resonance application to polysaccharide chemistry

    International Nuclear Information System (INIS)

    Nuclear magnetic resonance has been applied to polysaccharide chemistry using time averaging technique and high fields (100 and 250 MHz). The three methyl signals of methyl cellulose and cellulose triacetate are separated, and the C-6 substituent has been identified. Biosynthesis of bacterial cellulose has been performed using deuterium labelled D-glucose and Acetobacter xylinum. Per-acetylated derivative of bacterial cellulose has been studied by NMR; this study permitted us to determine the quantity of deuterium on each position of the anhydro-glucose unit in the polymer. NMR has also been used to see the anomeric end chain of cellulose and amylose derivatives and to show the fixation of bromine and t-butyl group on the free anomeric end chain of cellulose triacetate. (author)

  10. Applications of high dielectric materials in high field magnetic resonance

    Science.gov (United States)

    Haines, Kristina Noel

    At high magnetic fields, radiation losses, wavelength effects, self-resonance, and the high resistance of components all contribute to losses in conventional RF MRI coil designs. The hypothesis tested here is that these problems can be combated by the use of high permittivity ceramic materials at high fields. High permittivity ceramic dielectric resonators create strong uniform magnetic fields in compact structures at high frequencies and can potentially solve some of the challenges of high field coil design. In this study NMR probes were constructed for operation at 600 MHz (14.1 Tesla) and 900 MHz (21.1 Tesla) using inductively fed CaTiO3 (relative permittivity of 156-166) cylindrical hollow bore dielectric resonators. The designs showed the electric field is largely confined to the dielectric itself, with near zero values in the hollow bore, which accommodates the sample. The 600 MHz probe has an unmatched Q value greater than 2000. Experimental and simulation mapping of the RF field show good agreement, with the ceramic resonator giving a pulse width approximately 25% less than a loop gap resonator of similar inner dimensions. High resolution images, with voxel dimensions less than 50 microm3, have been acquired from fixed zebrafish samples, showing excellent delineation of several fine structures. The 900 MHz probe has an unmatched Q value of 940 and shows Q performance five times better than Alderman-Grant and loop-gap resonators of similar dimensions. High resolution images were acquired of an excised mouse spinal cord (25 microm 3) and an excised rat soleus muscle (20 microm3). The spatial distribution of electromagnetic fields within the human body can be tailored using external dielectric materials. Here, a new material is introduced with high dielectric constant and low background MRI signal. The material is based upon metal titanates, which can be made into geometrically formable suspensions in de-ionized water. The suspension's material properties are

  11. Resolution and sensitivity of high field nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    The arrival of very high field magnets and cryogenic circuitries, and the development of relaxation-optimized pulse sequences have added powerful tools for increasing sensitivity and resolution in NMR studies of biomacromolecules. The potential of these advances is not fully realized in practice, however, since current experimental protocols do not permit sufficient data sampling for optimal resolution in the indirect dimensions. Here we analyze quantitatively how increasing resolution in indirect dimensions affects the S/N ratio and compare this with currently used sampling routines. Optimal resolution would require sampling up to ∼3R2-1, and the S/N reaches a maximum at ∼1.2R2-1. Currently used data acquisition protocols rarely sample beyond 0.4R2-1, and extending evolution times would result in prohibitively long experiments. We show that a general solution to this problem is to use non-uniform sampling, where only a small subset of data points in the indirect sampling space are measured, and possibly different numbers of transients are collected for different evolution times. Coupled with modern methods of spectrum analysis, this strategy delivers substantially improved resolution and/or reduced measuring times compared to uniform sampling, without compromising sensitivity. Higher resolution in the indirect dimensions will facilitate the use of automated assignment programs

  12. Magnet Science and Technology for Basic Research at the High Field Laboratory for Superconducting Materials

    Institute of Scientific and Technical Information of China (English)

    渡辺和雄

    2007-01-01

    Since the first practical cryocooled superconducting magnet using a GM-cryocooler and high temperature superconducting current leads has been demonstrated successfully at the High Field Laboratory for Superconducting Materials (HFLSM), various kinds of cryocooled superconducting magnets in fields up to 15 T have been used to provide access for new research areas in fields of magneto-science. Recently, the HFLSM has succeeded in demonstrating a cryocooed 18 T high temperature superconducting magnet and a high field cryocooled 27.5 T hybrid magnet. Cryocooled magnet technology and basic research using high field magnets at the HFLSM are introduced.

  13. High field magnet program at Brookhaven National Laboratory

    CERN Document Server

    Ghosh, A; Muratore, J; Parker, B; Sampson, W; Wanderer, P J; Willen, E

    2000-01-01

    The magnet program at Brookhaven National Laboratory (BNL) is focussed on superconducting magnets for particle accelerators. The effort includes magnet production at the laboratory and in industry, magnet R&D, and test facilities for magnets and superconductors. Nearly 2000 magnets-dipoles, quadrupoles, sextupoles and correctors for the arc and insertion regions-were produced for the Relativistic Heavy Ion Collider (RHIC), which is being commissioned. Currently, production of helical dipoles for the polarized proton program at RHIC, insertion region dipoles for the Large Hadron Collider (LHC) at CERN, and an insertion magnet system for the Hadron-Elektron-Ring- Analage (HERA) collider at Deutsches Elektronen-Synchrotron (DESY) is underway. The R&D effort is exploring dipoles with fields above 10 T for use in post-LHC colliders. Brittle superconductors-Nb/sub 3/Sn or HTS-are being used for these magnets. The superconductor test facility measures short-sample currents and other characteristics of sample...

  14. High field properties of the AGS booster dipole magnet

    International Nuclear Information System (INIS)

    Various aspects of the design and use of the AGS booster dipole magnet are discussed. The original design criteria and choices are outlined and possible additional uses for the booster magnet are described. These include an antiproton beam storage ring and low energy antiproton beam acceleration. Emphasis, however, is placed on possible use for high energy antiproton beams. Initial calculations are presented which show that the magnet can be powered significantly above its design field, but more study is required on this option

  15. High-Field Magnetization of Light Rare-Earth Metals

    DEFF Research Database (Denmark)

    McEwen, K.A.; Cock, G.J.; Roeland, L.W.;

    1973-01-01

    The magnetization of single crystals of Eu, Sm, Nd, Pr, and Pr-Nd alloys has been measured in fields up to 37 T (370 kG). The results give new information on the magnetic properties of these metals. Of particular interest is a first-order transition from a nonmagnetic to a metamagnetic phase in d...

  16. High-field magnetization studies of NdNi5

    International Nuclear Information System (INIS)

    Magnetization studies on single-crystalline NdNi5 in external fields up to 35 T are reported. NdNi5 is a ferromagnet with a TC of 7.2 K and the easy magnetic direction is along the a direction. The spontaneous magnetic moment is 2.1μB/f.u. Along the c-axis, the magnetization amounts to 1.65μB/f.u. at 35 T. The magnetization process is analyzed within the crystalline electric field approach in combination with exchange interactions, taking into account the contribution of the Ni sublattice. The studies confirm that the charge-formed ground state of the f3 (Nd3+) subsystem is the state Γ8 with a dominant vertical stroke ±5/2 right angle contribution. The full magnetization curves, up to 300 T, have been calculated. The magnetization curve along the c-axis proceeds to saturation with a metamagnetic-like transition at 150 T. (orig.)

  17. Superconductor Requirements and Characterization for High Field Accelerator Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Barzi, E.; Zlobin, A. V.

    2015-05-01

    The 2014 Particle Physics Project Prioritization Panel (P5) strategic plan for U.S. High Energy Physics (HEP) endorses a continued world leadership role in superconducting magnet technology for future Energy Frontier Programs. This includes 10 to 15 T Nb3Sn accelerator magnets for LHC upgrades and a future 100 TeV scale pp collider, and as ultimate goal that of developing magnet technologies above 20 T based on both High Temperature Superconductors (HTS) and Low Temperature Superconductors (LTS) for accelerator magnets. To achieve these objectives, a sound conductor development and characterization program is needed and is herein described. This program is intended to be conducted in close collaboration with U.S. and International labs, Universities and Industry.

  18. A new support structure for high field magnets

    International Nuclear Information System (INIS)

    Pre-stress of superconducting magnets can be applied directly through the magnet yoke structure. We have replaced the collar functionality in our 14 Tesla R and D Nb3Sn dipole magnets with an assembly procedure based on an aluminum shell and bladders. Bladders, placed between the coil pack and surrounding yoke inside the shell, are pressurized up to 10 ksi [70 MPa] to create an interference gap. Keys placed into the interference gap replace the bladder functionality. Following the assembly, the bladders are deflated and removed. Strain gauges mounted directly on the shell are used to monitor the stress of the entire magnet structure, thereby providing a high degree of pre-stress control without the need for high tolerances. During assembly, a force of 8.2 x 105 lbs/ft [12 MN/m] is generated by the bladders and the stress in the 1.57 inch [40mm] aluminum shell reaches 20.3 ksi [140 MPa]. During cool-down the thermal expansion difference between shell and yoke generates an additional compressive force of 6.85 x 105 lbs/ft [10 MN/m], corresponding to a final stress in the shell of 39.2 ksi [270 MPa]. Pre-stress conditions are sufficient for 16 T before the coils separate at the bore. Bladders have now been used in the assembly and disassembly of two 14 T magnets. This paper describes the magnet structure, assembly procedure and test results

  19. Chest MRI

    Science.gov (United States)

    Nuclear magnetic resonance - chest; Magnetic resonance imaging - chest; NMR - chest; MRI of the thorax; Thoracic MRI ... healthy enough to filter the contrast. During the MRI, the person who operates the machine will watch ...

  20. High-Field Magnetization of Light Rare-Earth Metals

    DEFF Research Database (Denmark)

    McEwen, K.A.; Cock, G.J.; Roeland, L.W.;

    1973-01-01

    The magnetization of single crystals of Eu, Sm, Nd, Pr, and Pr-Nd alloys has been measured in fields up to 37 T (370 kG). The results give new information on the magnetic properties of these metals. Of particular interest is a first-order transition from a nonmagnetic to a metamagnetic phase in...... double-hexagonal close-packed Pr, due to the crossing of crystal-field levels, when a field of about 32 T is applied in the hard direction at low temperatures....

  1. Ultrasound versus high field magnetic resonance imaging in rheumatoid arthritis

    DEFF Research Database (Denmark)

    Tan, York Kiat; Østergaard, Mikkel; Bird, Paul;

    2014-01-01

    Over the past decade there have been significant advances in the field of musculoskeletal imaging, especially in the application of ultrasound (US) and magnetic resonance imaging (MRI) to the management of rheumatoid arthritis (RA). Both modalities offer significant advantages over the previous...

  2. A new support structure for high field magnets

    CERN Document Server

    Hafalia, R R; Caspi, S; Dietderich, D R; Gourlay, S A; Hannaford, R; Lietzke, A F; Liggins, N; McInturff, A D; Sabbi, G L; Scanlan, R M; O'Neill, J; Swanson, J H

    2002-01-01

    Pre-stress of superconducting magnets can be applied directly through the magnet yoke structure. We have replaced the collar functionality in our 14 Tesla R&D Nb//3Sn dipole magnets with an assembly procedure based on an aluminum shell and bladders. Bladders, placed between the coil pack and surrounding yoke inside the shell, are pressurized up to 10 ksi left bracket 70 MPa right bracket to create an interference gap. Keys placed into the interference gap replace the bladder functionality. Following the assembly, the bladders are deflated and removed. Strain gauges mounted directly on the shell are used to monitor the stress of the entire magnet structure, thereby providing a high degree of pre-stress control without the need for high tolerances. During assembly, a force of 8.2 multiplied by 10**5 lbs /ft left bracket 12 MN/m right bracket is generated by the bladders and the stress in the 1.57 double prime left bracket 40 mm right bracket aluminum shell reaches 20.3 ksi left bracket 140 MPa right bracket...

  3. 15 Years of R&D on High Field Accelerator Magnets at FNAL

    Energy Technology Data Exchange (ETDEWEB)

    Barzi, Emanuela [Fermilab; Zlobin, Alexander V. [Fermilab

    2015-12-10

    The High Field Magnet (HFM) Program at Fermi National Accelerator Laboratory (FNAL) has been developing Nb3Sn superconducting magnets, materials and technologies for present and future particle accelerators since the late 1990s. This paper summarizes the main results of the Nb3Sn accelerator magnet and superconductor R&D at FNAL and outlines the Program next steps.

  4. 15 Years of R&D on high field accelerator magnets at FNAL

    Science.gov (United States)

    Barzi, Emanuela; Zlobin, Alexander V.

    2016-07-01

    The High Field Magnet (HFM) Program at Fermi National Accelerator Laboratory (FNAL) has been developing Nb3Sn superconducting magnets, materials and technologies for present and future particle accelerators since the late 1990s. This paper summarizes the main results of the Nb3Sn accelerator magnet and superconductor R&D at FNAL and outlines the Program next steps.

  5. Gap Filling Ceramic Insulating Putty for High Field Magnets

    Science.gov (United States)

    Rice, J. A.; Rice, H. M.

    2008-03-01

    Gaps between the A15 superconducting cable and its supports can sometimes occur requiring expensive rework of the support or filling with a non-optimal material. Recently, a new ceramic putty has been developed that can fill these gaps to fully support the superconducting cable. This ceramic material can withstand the extreme temperature differences between the high temperature heat treatment and the cryogenic operation. Significant performance improvements have been made that will enable the insulating putty to be used in some accelerator magnet systems. Processing methods will be discussed as well as strength and thermal data.

  6. Correlating Hemodynamic Magnetic Resonance Imaging with high-field Intracranial Vessel Wall Imaging in Stroke

    Science.gov (United States)

    Langdon, Weston; Donahue, Manus J.; van der Kolk, Anja G.; Rane, Swati; Strother, Megan K.

    2014-01-01

    Vessel wall magnetic resonance imaging at ultra-high field (7 Tesla) can be used to visualize vascular lesions noninvasively and holds potential for improving stroke-risk assessment in patients with ischemic cerebrovascular disease. We present the first multi-modal comparison of such high-field vessel wall imaging with more conventional (i) 3 Tesla hemodynamic magnetic resonance imaging and (ii) digital subtraction angiography in a 69-year-old male with a left temporal ischemic infarct. PMID:25426229

  7. Correlating Hemodynamic Magnetic Resonance Imaging with high-field Intracranial Vessel Wall Imaging in Stroke

    OpenAIRE

    Langdon, Weston; Donahue, Manus J.; van der Kolk, Anja G.; Rane, Swati; Strother, Megan K.

    2014-01-01

    Vessel wall magnetic resonance imaging at ultra-high field (7 Tesla) can be used to visualize vascular lesions noninvasively and holds potential for improving stroke-risk assessment in patients with ischemic cerebrovascular disease. We present the first multi-modal comparison of such high-field vessel wall imaging with more conventional (i) 3 Tesla hemodynamic magnetic resonance imaging and (ii) digital subtraction angiography in a 69-year-old male with a left temporal ischemic infarct.

  8. DOUBLE DEGENERATE MERGERS AS PROGENITORS OF HIGH-FIELD MAGNETIC WHITE DWARFS

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Berro, Enrique; Loren-Aguilar, Pablo; Aznar-Siguan, Gabriela; Torres, Santiago; Camacho, Judit [Departament de Fisica Aplicada, Universitat Politecnica de Catalunya, c/Esteve Terrades, 5, 08860 Castelldefels (Spain); Althaus, Leandro G.; Corsico, Alejandro H. [Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque s/n, (1900) La Plata (Argentina); Kuelebi, Baybars; Isern, Jordi, E-mail: garcia@fa.upc.edu [Institute for Space Studies of Catalonia, c/Gran Capita 2-4, Edif. Nexus 104, 08034 Barcelona (Spain)

    2012-04-10

    High-field magnetic white dwarfs have been long suspected to be the result of stellar mergers. However, the nature of the coalescing stars and the precise mechanism that produces the magnetic field are still unknown. Here, we show that the hot, convective, differentially rotating corona present in the outer layers of the remnant of the merger of two degenerate cores can produce magnetic fields of the required strength that do not decay for long timescales. Using a state-of-the-art Monte Carlo simulator, we also show that the expected number of high-field magnetic white dwarfs produced in this way is consistent with that found in the solar neighborhood.

  9. Exploration of Traveling Waves in High Field Magnetic Resonance Imaging

    Science.gov (United States)

    Hernandez, Zachary

    2010-10-01

    MRI has been a remarkable means of medical imaging for the last three decades without exposure to ionizing radiation. The increase in MRI signal with the increase of magnetic field strength is the main motive in a move towards imaging at higher field strengths. However, the advent of higher field strength MRI has come with the challenge of maintaining homogeneous excitation fields (B1). One promising solution to this has been to transmit radio-frequency (RF) signals using a patch antenna instead of the usual RF coil. This technique exploits the theory of waveguides and traveling waves typically used in high frequency applications. In this particular study we have investigated this unique application by measuring B1 maps, geometric distortions, and signal-to-noise ratios (SNRs) in order to better quantify its potential in MRI. Using phantoms to match the similar physical features of the human head/torso region, we ran comparative scans using the traveling wave setup versus the conventional head volume coil setup on a Philips 7 Tesla MRI scanner. The goal of this experiment was to systematically measure B1 maps for flip angle efficiency and multi-planar rendering images for geometric distortion. Although the application of traveling wave in MRI does suffer from low excitation (small flip angles), there seems to be little to no correlation between traveling wave phase variability and frequency/phase encoding. Therefore, further experiments, if carried out, may enhance image quality such as RF shielding, the use of local receive coils, and/or the addition of a second patch antenna.

  10. High-Field Magnetization of the Pyrochlore Compound Gd2Ti2O7

    Science.gov (United States)

    Narumi, Yasuo; Kikkawa, Akiko; Katsumata, Koichi; Honda, Zentaro; Hagiwara, Masayuki; Kindo, Koichi

    2006-09-01

    High-field magnetization measurements have been preformed on a single crystal sample of the pyrochlore compound Gd2Ti2O7 using a pulse magnet in conjunction with a dilution refrigerator. The magnetization curve at 0.3 K reveals two magnetic phase transitions when the magnetic field is applied along b [111]. At temperatures slightly above TN, a magnetization plateau appears around 5 T and the magnetization increases again from about 15 T with a convex curvature. It is considered that this crossover is due to a competition among thermal fluctuations, short-range antiferromagnetic ordering and geometrical frustration.

  11. High-field magnetization of rare-earth ions in scandium

    DEFF Research Database (Denmark)

    Roeland, L. W.; Touborg, P.

    1978-01-01

    The magnetic moments of Tb, Dy, or Er ions in dilute Sc single-crystal alloys have been measured in fields up to 280 × 105 A/m (350 kOe). The Zeeman energies in this high field are comparable to the total crystal-field splittings. This gives rise to characteristic features in the magnetization cu...

  12. Nb$_3$Sn High Field Magnets for the High Luminosity LHC Upgrade Project

    Energy Technology Data Exchange (ETDEWEB)

    Ambrosio, Giorgio [Fermilab

    2015-01-01

    The High Luminosity upgrade of the Large Hadron Collider at CERN requires a new generation of high field superconducting magnets. High field large aperture quadrupoles (MQXF) are needed for the low-beta triplets close to the ATLAS and CMS detectors, and high field two-in-one dipoles (11 T dipoles) are needed to make room for additional collimation. The MQXF quadrupoles, with a field gradient of 140 T/m in 150 mm aperture, have a peak coil field of 12.1 T at nominal current. The 11 T dipoles, with an aperture of 60 mm, have a peak coil field of 11.6 T at nominal current. Both magnets require Nb3Sn conductor and are the first applications of this superconductor to actual accelerator magnets.

  13. Design of the EuCARD High-Field Model Dipole Magnet FRESCA2

    CERN Document Server

    Milanese, A; Durante, M; Manil, P; Perez, J C; Rifflet, J M; de Rijk, G; Rondeaux, F

    2012-01-01

    This paper reports on the design of FRESCA2, a dipole magnet model wound with Nb3Sn Rutherford cable. This magnet is one of the deliverables of the High Field Magnets work package of the European FP7-EuCARD project. The nominal magnetic flux density of 13 Tesla in a 100 mm bore will make it suitable for upgrading the FRESCA cable test facility at CERN. The magnetic layout is based on a block coil, with four layers per pole. The mechanical structure is designed to provide adequate pre-stress, through the use of bladders, keys and an aluminum alloy shrinking cylinder.

  14. Design of the EuCARD high field model dipole magnet FRESCA2

    CERN Document Server

    Milanese, A; Durante, M; Manil, P; Perez, J-C; Rifflet, J-M; de Rijk, G; Rondeaux, F

    2011-01-01

    This paper reports on the design of FRESCA2, a dipole magnet model wound with Nb3Sn Rutherford cable. This magnet is one of the deliverables of the High Field Magnets work package of the European FP7-EuCARD project. The nominal magnetic flux density of 13 Tesla in a 100 mm bore will make it suitable for upgrading the FRESCA cable test facility at CERN. The magnetic layout is based on a block coil, with four layers per pole. The mechanical structure is designed to provide adequate pre-stress, through the use of bladders, keys and an aluminum alloy shrinking cylinder.

  15. Double degenerate mergers as progenitors of high-field magnetic white dwarfs

    CERN Document Server

    García--Berro, E; Aznar--Siguán, G; Torres, S; Camacho, J; Althaus, L G; Córsico, A H; Külebi, B; Isern, J

    2012-01-01

    High-field magnetic white dwarfs have been long suspected to be the result of stellar mergers. However, the nature of the coalescing stars and the precise mechanism that produces the magnetic field are still unknown. Here we show that the hot, convective, differentially rotating corona present in the outer layers of the remnant of the merger of two degenerate cores is able to produce magnetic fields of the required strength that do not decay for long timescales. We also show, using an state-of-the-art Monte Carlo simulator, that the expected number of high-field magnetic white dwarfs produced in this way is consistent with that found in the Solar neighborhood.

  16. Development of High-Field Permanent Magnetic Circuits for NMRI/MRI and Imaging on Mice

    Directory of Open Access Journals (Sweden)

    Guangxin Wang

    2016-01-01

    Full Text Available The high-field permanent magnetic circuits of 1.2 T and 1.5 T with novel magnetic focusing and curved-surface correction are developed. The permanent magnetic circuit comprises a magnetic yoke, main magnetic steel, nonspherical curved-surface magnetic poles, plugging magnetic steel, and side magnetic steel. In this work, a novel shimming method is proposed for the effective correction of base magnetic field (B0 inhomogeneities, which is based on passive shimming on the telescope aspheric cutting, grinding, and fine processing technology of the nonspherical curved-surface magnetic poles and active shimming adding higher-order gradient coils. Meanwhile, the magnetic resonance imaging dedicated alloy with high-saturation magnetic field induction intensity and high electrical resistivity is developed, and nonspherical curved-surface magnetic poles which are made of the dedicated alloy have very good anti-eddy-current effect. In addition, the large temperature coefficient problem of permanent magnet can be effectively controlled by using a high quality temperature controller and deuterium external locking technique. Combining our patents such as gradient coil, RF coil, and integration computer software, two kinds of small animal Micro-MRI instruments are developed, by which the high quality MRI images of mice were obtained.

  17. A COMMON COIL DESIGN FOR HIGH FIELD 2 IN 1 ACCELERATOR MAGNETS.

    Energy Technology Data Exchange (ETDEWEB)

    GUPTA,R.

    2002-05-12

    A common coil design concept for 2-in-1 superconducting accelerator magnets is presented. It practically eliminates the major problems in the ends of high field magnets built with either high temperature superconductors (HTS) or conventional superconductors. Racetrack coils, consisting of rectangular blocks built with either superconducting tapes or cables, are common to both apertures with each aperture containing one half of each coil. The ends are easy to wind with the conductors experiencing little strain. The overall magnet design, construction and tooling are also expected to be simpler than in the conventional cosine theta magnets. The concept is also suitable for superferric and combined function magnet designs. A modular design for an HTS based R&D magnet is also presented.

  18. What Is Chest MRI?

    Science.gov (United States)

    ... from the NHLBI on Twitter. What Is Chest MRI? Chest MRI (magnetic resonance imaging) is a safe, noninvasive test. "Noninvasive" means that ... your chest wall, heart, and blood vessels. Chest MRI uses radio waves, magnets, and a computer to ...

  19. Very high field magnetization and AC susceptibility of native horse spleen ferritin

    Energy Technology Data Exchange (ETDEWEB)

    Guertin, R.P. [Department of Physics and Astronomy, Room 201, Science and Technology Center, Tufts University, Medford, MA 02155 (United States)]. E-mail: robert.guertin@tufts.edu; Harrison, N. [National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Zhou, Z.X. [MS6056, Oak Ridge National Laboratory, Oak Ridge, TN 37830 (United States); McCall, S. [Lawrence Livermore National Laboratory, PO Box 808, Livermore, CA 94551 (United States); Drymiotis, F. [Department of Physics and Astronomy, Clemson University, Clemson, SC 29634 (United States)

    2007-01-15

    The magnetization of native horse spleen ferritin protein is measured in pulsed magnetic fields to 55 T at T=1.52 K. The magnetization rises smoothly with negative curvature due to uncompensated Fe{sup 3+} spins and with a large high field slope due to the underlying antiferromagnetic ferritin core. Even at highest fields the magnetic moment is only {approx}4% of the saturation moment of the full complement of Fe{sup 3+} in the ferritin molecule. The AC magnetic susceptibility, {chi} {sub AC}(T,f), responding to the uncompensated spins, reaches a maximum near the superparamagnetic blocking temperature with the temperature of the maximum, T {sub M}, varying with excitation frequency, T {sub M} {sup -1} {alpha} log f for 10{<=}f{<=}10{sup 4} Hz.

  20. Development of superconducting magnet for high-field MR systems in China

    Science.gov (United States)

    Wang, Zanming; van Oort, Johannes M.; Zou, Mark X.

    2012-11-01

    In this paper we describe the development of superconducting magnets for high-field Magnetic Resonance Imaging (MRI) by various businesses and institutions in China. As the Chinese MR market rapidly expands, many foreign and domestic companies and research institutions are joining the race to meet the burgeoning demand by developing key MRI components for various magnetic field configurations. After providing a brief introduction to research on MRI superconducting magnets that dates back to the 1980s, the first large-bore 1.5 T superconducting magnet with 50-cm DSV for whole-body MRI - successfully developed and manufactured by AllTech Medical Systems in Chengdu, China-is presented and its specifications are described.

  1. High-field magnetic resonance imaging of the human temporal lobe ☆

    OpenAIRE

    Colon-Perez, Luis M.; Michael King; Mansi Parekh; Angelique Boutzoukas; Eduardo Carmona; Michelle Couret; Rosemary Klassen; Mareci, Thomas H.; Carney, Paul R.

    2015-01-01

    Background: Emerging high-field diffusion weighted MR imaging protocols, along with tractography, can elucidate microstructural changes associated with brain disease at the sub-millimeter image resolution. Epilepsy and other neurological disorders are accompanied by structural changes in the hippocampal formation and associated regions; however, these changes can be subtle and on a much smaller scale than the spatial resolution commonly obtained by current clinical magnetic resonance (MR) pro...

  2. Formation of high-field magnetic white dwarfs from common envelopes.

    Science.gov (United States)

    Nordhaus, Jason; Wellons, Sarah; Spiegel, David S; Metzger, Brian D; Blackman, Eric G

    2011-02-22

    The origin of highly magnetized white dwarfs has remained a mystery since their initial discovery. Recent observations indicate that the formation of high-field magnetic white dwarfs is intimately related to strong binary interactions during post-main-sequence phases of stellar evolution. If a low-mass companion, such as a planet, brown dwarf, or low-mass star, is engulfed by a post-main-sequence giant, gravitational torques in the envelope of the giant lead to a reduction of the companion's orbit. Sufficiently low-mass companions in-spiral until they are shredded by the strong gravitational tides near the white dwarf core. Subsequent formation of a super-Eddington accretion disk from the disrupted companion inside a common envelope can dramatically amplify magnetic fields via a dynamo. Here, we show that these disk-generated fields are sufficiently strong to explain the observed range of magnetic field strengths for isolated, high-field magnetic white dwarfs. A higher-mass binary analogue may also contribute to the origin of magnetar fields.

  3. Low magnetic moment PIN diodes for high field MRI surface coils.

    Science.gov (United States)

    Voskoboynik, Pavel; Joos, Ronald D; Doherty, W E; Goldfarb, Ron B

    2006-12-01

    Positive-intrinsic-negative (PIN) silicon diodes are commonly used in magnetic resonance imaging (MRI) coils to perform active or passive blocking and detuning, or to disable circuit functions. However, diode packages with large magnetic moments are known to cause image artifacts in high field MRI systems. In this study, diode packages with low magnetic moment were designed by compensating components of ferromagnetic nickel and paramagnetic tungsten with diamagnetic silver. The new diodes have an initial positive susceptibility up to fields of 1 T and a negative susceptibility from 1 to 7 T. Their magnetic moments are one to two orders of magnitude smaller than those of standard diodes; moments as small as 20 nJ/T at 7 T were achieved. PMID:17278801

  4. A new hybrid protection system for high-field superconducting magnets

    CERN Document Server

    Ravaioli, E; Kirby, G; ten Kate, H H J; Verweij, A P

    2014-01-01

    The new generation of high-field superconducting accelerator magnets poses a challenge concerning the protection of the magnet coil in the case of a quench. The very high stored energy per unit volume requires a fast and efficient quench heating system in order to avoid damage due to overheating. A new protection system for superconducting magnets is presented, comprising a combination of a novel coupling-loss induced quench (CLIQ) system and conventional quench heaters. CLIQ can provoke a very fast transition to the normal state in coil windings by introducing coupling loss and thus heat in the coil's conductor. The advantage of the hybrid protection system is a global transition, resulting in a much faster current decay, a significantly lower hot-spot temperature, and a more homogeneous temperature distribution in the magnet's coil.

  5. A high-field (30 Tesla) pulsed magnet instrument for single-crystal scattering studies

    Science.gov (United States)

    Islam, Zahirul; Nojiri, Hiroyuki; Narumi, Yasuo; Lang, Jonathan

    2010-03-01

    Pulsed magnets have emerged as a viable approach at synchrotron x-ray facilities for studying materials in high magnetic fields. We are developing a new high-field (30 Tesla) pulsed magnet system for single-crystal x-ray diffraction studies. It consists of a single 18mm-bore solenoid, designed and built at Tohoku University using high-tensile-strength and high conductivity CuAg wires. A dual-cryostat scheme has been developed at Advanced Photon Source in order to cool the coil using liquid nitrogen and the sample using a closed-cycle cryostat independently. Liquid nitrogen cooling allows repetition rate of a few minutes for peak fields near 30 Tesla. This scheme is unique in that it allows the applied magnetic field to be parallel to the scattering plane. Time-resolved scattering data are typically collected using a fast one-dimensional strip detector. Opportunities and challenges for experiments and instrumentation will be discussed.

  6. Stress management as an enabling technology for high-field superconducting dipole magnets

    Science.gov (United States)

    Holik, Eddie Frank, III

    This dissertation examines stress management and other construction techniques as means to meet future accelerator requirement demands by planning, fabricating, and analyzing a high-field, Nb3Sn dipole. In order to enable future fundamental research and discovery in high energy accelerator physics, bending magnets must access the highest fields possible. Stress management is a novel, propitious path to attain higher fields and preserve the maximum current capacity of advanced superconductors by managing the Lorentz stress so that strain induced current degradation is mitigated. Stress management is accomplished through several innovative design features. A block-coil geometry enables an Inconel pier and beam matrix to be incorporated in the windings for Lorentz Stress support and reduced AC loss. A laminar spring between windings and mica paper surrounding each winding inhibit any stress transferral through the support structure and has been simulated with ALGORRTM. Wood's metal filled, stainless steel bladders apply isostatic, surface-conforming preload to the pier and beam support structure. Sufficient preload along with mica paper sheer release reduces magnet training by inhibiting stick-slip motion. The effectiveness of stress management is tested with high-precision capacitive stress transducers and strain gauges. In addition to stress management, there are several technologies developed to assist in the successful construction of a high-field dipole. Quench protection has been designed and simulated along with full 3D magnetic simulation with OPERARTM. Rutherford cable was constructed, and cable thermal expansion data was analysed after heat treatment. Pre-impregnation analysis techniques were developed due to elemental tin leakage in varying quantities during heat treatment from each coil. Robust splicing techniques were developed with measured resistivites consistent with nO joints. Stress management has not been incorporated by any other high field dipole

  7. Powder-in-tube (PIT) $Nb_{3}Sn$ conductors for high-field magnets

    CERN Document Server

    Lindenhovius, J L H; den Ouden, A; Wessel, W A J; ten Kate, H H J

    2000-01-01

    New Nb/sub 3/Sn conductors, based on the powder-in-tube (PIT) process, have been developed for application in accelerator magnets and high-field solenoids. For application in accelerator magnets, SMI has developed a binary 504 filament PIT conductor by optimizing the manufacturing process and adjustment of the conductor lay-out. It uniquely combines a non-copper current density of 2680 A/mm/sup 2/@10 T with an effective filament diameter of about 20 mu m. This binary conductor may be used in a 10 T, wide bore model separator dipole magnet for the LHC, which is being developed by a collaboration of the University of Twente and CERN. A ternary (Nb/7.5wt%Ta)/sub 3/Sn conductor containing 37 filaments is particularly suited for application in extremely high-field superconducting solenoids. This wire features a copper content of 43%, a non-copper current density of 217 A/mm/sup 2/@20 T and a B/sub c2/ of 25.6 T. The main issues and the experimental results of the development program of PIT Nb/sub 3/Sn conductors a...

  8. Thermal Design of an Nb3Sn High Field Accelerator Magnet

    CERN Document Server

    Pietrowicz, S

    2011-01-01

    Within the framework of the European project EuCARD, a Nb3Sn high field accelerator magnet is under design to serve as a test bed for future high field magnets and to upgrade the vertical CERN cable test facility, Fresca. The Fresca 2 block coil type magnet will be operated at 1.9 K or 4.2 K and is designed to produce about 13 T. A 2D numerical thermal model was developed to determinate the temperature margin of the coil in working conditions and the appropriate cool-down scenario. The temperature margin, which is DTmarge=5.8 K at 1.9 K and DTmarge=3.5 K at 4.2 K, was investigated in steady state condition with the AC losses due to field ramp rate as input heat generation. Several cool-down scenarios were examined in order to minimize the temperature difference and therefore reducing the mechanical constraints within the structure. The paper presents the numerical model, the assumptions taken for the calculations and several results of the simulation for the cool-down and temperature distributions due to seve...

  9. A Method to Localize RF B1 Field in High-Field Magnetic Resonance Imaging Systems

    OpenAIRE

    Yoo, Hyoungsuk; Gopinath, Anand; Vaughan, J. Thomas

    2012-01-01

    In high-field magnetic resonance imaging (MRI) systems, B0 fields of 7 and 9.4 T, the RF field shows greater inhomogeneity compared to clinical MRI systems with B0 fields of 1.5 and 3.0 T. In multichannel RF coils, the magnitude and phase of the input to each coil element can be controlled independently to reduce the nonuniformity of the RF field. The convex optimization technique has been used to obtain the optimum excitation parameters with iterative solutions for homogeneity in a selected ...

  10. Superconductor and cable R&D for high field accelerator magnets at Fermilab

    CERN Document Server

    Barzi, E; Andreev, N; Bauer, P; Chichili, D R; Fratini, M; Elementi, L; Hoffman, J; Limon, P J; Mattafirri, S; Rey, J M; Yamada, R; Zlobin, A V

    2002-01-01

    This paper presents past results and future goals of the Nb/sub 3/Sn strand and cable R&D being performed within the High Field Magnet program at Fermilab. Research tools include a reaction site for Nb /sub 3/Sn, a Short Sample Test Facility, a Scanning Electron Microscope, and a 28-strand cabling machine. Strands of various designs and diameters produced with the Internal Tin, Modified Jelly Roll, and Powder-in-Tube methods, and several Rutherford-type cables were studied. (18 refs).

  11. High-field superconducting window-frame beam-transport magnets

    International Nuclear Information System (INIS)

    The window-frame design for high-field superconducting beam-transport magnets was first applied to two, 2-m-long, 4-T modules of an 80 bending magent which has operated for nine years in the primary proton beam line at the Brookhaven National Laboratory Alternating Gradient Synchrotron (AGS). The design of two 1.5-m long, 7.6-cm cold-bore superconducting windowframe magnets, described in this paper, intended for the external proton beam transport system at the AGS incorporated evolutionary changes. These magnets generated a maximum aperture field of 6.8 T with a peak field in the dipole coil of 7.1 T. Measured fields are very accurate and are compared to values calculated using the computer programs LINDA and POISSON. Results of quench-propagation studies demonstrate the excellent thermal stability of the magnets. The magnets quench safely without energy extraction at a maximum current density, J = 130 kA/cm2 in the superconductor, corresponding to J = 57.6 kA/cm2 overall the conductor at B = 6.7 T

  12. 2-D/3-D quench simulation using ANSYS for epoxy impregnated $Nb_{3}$ Sn high field magnets

    CERN Document Server

    Yamada, R; Marscin, E; Rey, J M; Wake, M

    2003-01-01

    A quench program using ANSYS is developed for the high field collider magnet for 3-D analysis. Its computational procedure is explained. The quench program is applied to a one meter Nb/sub 3/Sn high field model magnet, which is epoxy impregnated. The quench simulation program is used to estimate the temperature and mechanical stress inside the coil as well as over the whole magnet. It is concluded that for the one meter magnet with the presented cross section and configuration, the thermal effects due to the quench is tolerable. But we need much more quench study and improvements in the design for longer magnets. (6 refs).

  13. Oxypnictide SmFeAs(O,F) superconductor: a candidate for high-field magnet applications.

    Science.gov (United States)

    Iida, Kazumasa; Hänisch, Jens; Tarantini, Chiara; Kurth, Fritz; Jaroszynski, Jan; Ueda, Shinya; Naito, Michio; Ichinose, Ataru; Tsukada, Ichiro; Reich, Elke; Grinenko, Vadim; Schultz, Ludwig; Holzapfel, Bernhard

    2013-01-01

    The recently discovered oxypnictide superconductor SmFeAs(O,F) is the most attractive material among the Fe-based superconductors due to its highest transition temperature of 56 K and potential for high-field performance. In order to exploit this new material for superconducting applications, the knowledge and understanding of its electro-magnetic properties are needed. Recent success in fabricating epitaxial SmFeAs(O,F) thin films opens a great opportunity to explore their transport properties. Here we report on a high critical current density of over 10(5) A/cm(2) at 45 T and 4.2 K for both main field orientations, feature favourable for high-field magnet applications. Additionally, by investigating the pinning properties, we observed a dimensional crossover between the superconducting coherence length and the FeAs interlayer distance at 30-40 K, indicative of a possible intrinsic Josephson junction in SmFeAs(O,F) at low temperatures that can be employed in electronics applications such as a terahertz radiation source and a superconducting Qubit.

  14. A low-cost, high-field-strength magnetic resonance imaging-compatible actuator.

    Science.gov (United States)

    Secoli, Riccardo; Robinson, Matthew; Brugnoli, Michele; Rodriguez y Baena, Ferdinando

    2015-03-01

    To perform minimally invasive surgical interventions with the aid of robotic systems within a magnetic resonance imaging scanner offers significant advantages compared to conventional surgery. However, despite the numerous exciting potential applications of this technology, the introduction of magnetic resonance imaging-compatible robotics has been hampered by safety, reliability and cost concerns: the robots should not be attracted by the strong magnetic field of the scanner and should operate reliably in the field without causing distortion to the scan data. Development of non-conventional sensors and/or actuators is thus required to meet these strict operational and safety requirements. These demands commonly result in expensive actuators, which mean that cost effectiveness remains a major challenge for such robotic systems. This work presents a low-cost, high-field-strength magnetic resonance imaging-compatible actuator: a pneumatic stepper motor which is controllable in open loop or closed loop, along with a rotary encoder, both fully manufactured in plastic, which are shown to perform reliably via a set of in vitro trials while generating negligible artifacts when imaged within a standard clinical scanner. PMID:25833997

  15. Cost Effective Open Geometry HTS MRI System amended to BSCCO 2212 Wire for High Field Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Kennth Marken

    2006-08-11

    the project start and that date a substantial shift in the MRI marketplace occurred, with rapid growth for systems at higher fields (1.5 T and above) and a consequent decline in the low field market (<1.0 T). While the project aim appeared technically attainable at that time, the conclusion was reached that the system and market economics do not warrant additional investment. The program was redirected to develop BSCCO 2212 multifilament wire development for high field superconducting magnets for NMR and other scientific research upon an agreement between DOE and Oxford Instruments, Superconducting Technology. The work t took place between September, 2004 and the project end in early 2006 was focused on 2212 multifilamentary wire. This report summarizes the technical achievements both in 2212 dip coated for an HTS MRI system and in BSCCO 2212 multifilamentary wire for high field magnets.

  16. High-field electron transport in GaN under crossed electric and magnetic fields

    Science.gov (United States)

    Kochelap, V. A.; Korotyeyev, V. V.; Syngayivska, G. I.; Varani, L.

    2015-10-01

    High-field electron transport studied in crossed electric and magnetic fields in bulk GaN with doping of 1016 cm-3, compensation around 90% at the low lattice temperature (30 K). It was found the range of the magnetic and electric fields where the non-equilibrium electron distribution function has a complicated topological structure in the momentum space with a tendency to the formation of the inversion population. Field dependences of dissipative and Hall components of the drift velocity were calculated for the samples with short- and open- circuited Hall contacts in wide ranges of applied electric (0 — 20 kV/cm) and magnetic (1 — 10 T) fields. For former sample, field dependences of dissipative and Hall components of the drift velocity have a non-monotonic behavior. The dissipative component has the inflection point which corresponds to the maximum point of the Hall component. For latter sample, the drift velocity demonstrate a usual sub-linear growth without any critical points. We found that GaN samples with controlled resistance of the Hall circuit can be utilized as a electronic high-power switch.

  17. Costs of high-field superconducting strands for particle accelerator magnets

    CERN Document Server

    Cooley, L D; Scanlan, R M; 10.1088/0953-2048/18/4/R01

    2005-01-01

    The costs of superconducting magnet strands are compared by calculating a 'production scaling factor' P that relates purchase data to the cost of raw materials. Using a consistent method, we normalize for different conductor geometries and strand diameters to arrive at cost indices in $ kg/sup -1/, $ m/sup -1/, and $ kA/sup -1/ m/sup -1/. Analyses of Nb47Ti conductors taken from the past 25 years of high-field magnet projects reveal that the price of raw materials and, to a lesser extent, finished strands, have tracked the price of niobium pentoxide. Performance gains during the 1980s produced $ kA /sup -1/ m/sup -1/ indices that fell with time ahead of strand cost in $ m/sup -1/, a situation that may reflect the present status of Nb /sub 3/Sn magnet conductors. Analyses of present materials show that P decreases systematically with billet mass. While production strands in 200-500 kg billets have costs ~3 times the cost of raw materials, the 20-50 kg billet size for internal-tin Nb/sub 3/Sn composites drives ...

  18. Shrink Tube Insulation Apparatus for Rebco Superconducting Tapes for Use in High Field Magnets

    CERN Document Server

    Whittington, Andrew

    An increasing number of applications require the use of high temperature superconductors (HTS) such as (RE=Rare Earth) Ba2Cu3O7-x (REBCO) coated conductors [1]. HTS conductors show particularly great potential for high field magnets applications [1] due to their high upper critical fields [2], But several groups have shown that REBCO coated conductors are prone to delamination failure [3] [4] [5]. Under relatively low transverse stress the HTS film separates from the substrate and the conductor degrades [6]. This is problematic due to high transverse stresses that occur in fully epoxy impregnated solenoids wound with this conductor. Application of thin walled heat shrink tubing introduces a weak plane around the conductor, preventing delamination degradation [7]. However, manual application of the shrink tubing is impractical, requiring three operators limited to insulating 100 m lengths or less of REBCO conductor. The high risk of damage to the conductor, also associated with this process, shows the need for...

  19. Application of high-field-strength magnetic resonance imaging to diagnose recurrent gastric carcinoma

    International Nuclear Information System (INIS)

    Objective: To evaluate the clinical application of high-field-strength magnetic resonance imaging to diagnose recurrent gastric cancer. Methods: Forty three postoperative patients with gastric carcinoma were divided into two groups. The group with recurrent gastric carcinoma has 33 patients, they were clinically confirmed by barium meal of alimentary canal, CT or pathological results. There were 10 cases in control group confirmed by pathological results. All the subjects took hypotonicity agent, followed by water as negative contrast medium. Then patients underwent magnetic resonance imaging including fast spoiled gradient recalled T1WI, T2WI, diffusion weighted imaging, fast imaging employing steady state sequence, magnetic resonance cholangiopancreatography and dynamic contrast enhancement sequences when gastrointestinal tract was in hypotonic, patients drank or were primed with water as contrast. Results: Thirty patients were diagnosed as recurrent gastric cancer with MRI, 28 of them were confirmed by clinical results. Three patients were missed and two patients were incorrectly misdiagnosed by MRI. Wall thickness of gastric remnant was (4.5±0.3) mm and that of stomas was (6.3±1.4) mm in control group. Types of lesions were found on MRI: thickening of remnant stomach stomas was more than 8 mm (n=30), thickening of neighbor remnant stomach stomas was more than 5 mm (n=19), mass of stomas (n=11), metastasis of neighbor viscus (n=5), and metastasis of lymph nodes (n=9). On enhancement scan, 9 patients showed inhomogeneous enhancement in arterial phase and 30 patients showed gradual delayed enhancement in venous phase and equilibrium phase. Conclusion: MRI is an effective imaging method in illustrating wall thickness of gastric remnant and stomas, invasion depth by carcinoma, relationship with neighbor tissue structures and metastasis of lymph nodes and abdominal viscus. It plays an important role in directing clinical therapy. (authors)

  20. ECG-based gating in ultra high field cardiovascular magnetic resonance using an independent component analysis approach

    OpenAIRE

    Krug, Johannes W; Rose, Georg; Clifford, Gari D.; Oster, Julien

    2013-01-01

    Background In Cardiovascular Magnetic Resonance (CMR), the synchronization of image acquisition with heart motion is performed in clinical practice by processing the electrocardiogram (ECG). The ECG-based synchronization is well established for MR scanners with magnetic fields up to 3 T. However, this technique is prone to errors in ultra high field environments, e.g. in 7 T MR scanners as used in research applications. The high magnetic fields cause severe magnetohydrodynamic (MHD) effects w...

  1. A method to localize RF B₁ field in high-field magnetic resonance imaging systems.

    Science.gov (United States)

    Yoo, Hyoungsuk; Gopinath, Anand; Vaughan, J Thomas

    2012-12-01

    In high-field magnetic resonance imaging (MRI) systems, B₀ fields of 7 and 9.4 T, the RF field shows greater inhomogeneity compared to clinical MRI systems with B₀ fields of 1.5 and 3.0 T. In multichannel RF coils, the magnitude and phase of the input to each coil element can be controlled independently to reduce the nonuniformity of the RF field. The convex optimization technique has been used to obtain the optimum excitation parameters with iterative solutions for homogeneity in a selected region of interest. The pseudoinverse method has also been used to find a solution. The simulation results for 9.4- and 7-T MRI systems are discussed in detail for the head model. Variation of the simulation results in a 9.4-T system with the number of RF coil elements for different positions of the regions of interest in a spherical phantom are also discussed. Experimental results were obtained in a phantom in the 9.4-T system and are compared to the simulation results and the specific absorption rate has been evaluated. PMID:22929360

  2. Analysis of Uncertainties in Protection Heater Delay Time Measurements and Simulations in Nb$_{3}$Sn High-Field Accelerator Magnets

    CERN Document Server

    Salmi, Tiina; Marchevsky, Maxim; Bajas, Hugo; Felice, Helene; Stenvall, Antti

    2015-01-01

    The quench protection of superconducting high-field accelerator magnets is presently based on protection heaters, which are activated upon quench detection to accelerate the quench propagation within the winding. Estimations of the heater delay to initiate a normal zone in the coil are essential for the protection design. During the development of Nb3Sn magnets for the LHC luminosity upgrade, protection heater delays have been measured in several experiments, and a new computational tool CoHDA (Code for Heater Delay Analysis) has been developed for heater design. Several computational quench analyses suggest that the efficiency of the present heater technology is on the borderline of protecting the magnets. Quantifying the inevitable uncertainties related to the measured and simulated delays is therefore of pivotal importance. In this paper, we analyze the uncertainties in the heater delay measurements and simulations using data from five impregnated high-field Nb3Sn magnets with different heater geometries. ...

  3. A design of novel type superconducting magnet for super-high field functional magnetic resonance imaging by using the harmonic analysis method of magnetic vector potentials

    Institute of Scientific and Technical Information of China (English)

    俎栋林; 郭华; 宋枭禹; 包尚联

    2002-01-01

    The approach of expanding the magnetic scalar potential in a series of Legendre polynomials is suitable for designing a conventional superconducting magnetic resonance imaging magnet of distributed solenoidal configuration. Whereas the approach of expanding the magnetic vector potential in associated Legendre harmonics is suitable for designing a single-solenoid magnet that has multiple tiers, in which each tier may have multiple layers with different winding lengths. A set of three equations to suppress some of the lowest higher-order harmonics is found. As an example, a 4T single-solenoid magnetic resonance imaging magnet with 4 × 6 layers of superconducting wires is de signed The degree of homogeneity in the 0.5m diameter sphere volume is better than 5.8 ppm. The same degree of homogeneity is retained after optimal integralization of turns in each correction layer. The ratio Bm/Bo in the single-solenoid magnet is 30%lower than that in the conventional six-solenoid magnet. This tolerates higher rated superconducting current in the coil. The Lorentz force of the coil in the single-solenoid system is also much lower than in the six-solenoid system. This novel type of magnet possesses significant advantage over conventional magnets, especially when used as a super-high field functional magnetic resonance imaging magnet.

  4. Measuring aortic pulse wave velocity using high-field cardiovascular magnetic resonance: comparison of techniques

    Directory of Open Access Journals (Sweden)

    Shaffer Jean M

    2010-05-01

    Full Text Available Abstract Background The assessment of arterial stiffness is increasingly used for evaluating patients with different cardiovascular diseases as the mechanical properties of major arteries are often altered. Aortic stiffness can be noninvasively estimated by measuring pulse wave velocity (PWV. Several methods have been proposed for measuring PWV using velocity-encoded cardiovascular magnetic resonance (CMR, including transit-time (TT, flow-area (QA, and cross-correlation (XC methods. However, assessment and comparison of these techniques at high field strength has not yet been performed. In this work, the TT, QA, and XC techniques were clinically tested at 3 Tesla and compared to each other. Methods Fifty cardiovascular patients and six volunteers were scanned to acquire the necessary images. The six volunteer scans were performed twice to test inter-scan reproducibility. Patient images were analyzed using the TT, XC, and QA methods to determine PWV. Two observers analyzed the images to determine inter-observer and intra-observer variabilities. The PWV measurements by the three methods were compared to each other to test inter-method variability. To illustrate the importance of PWV using CMR, the degree of aortic stiffness was assessed using PWV and related to LV dysfunction in five patients with diastolic heart failure patients and five matched volunteers. Results The inter-observer and intra-observer variability results showed no bias between the different techniques. The TT and XC results were more reproducible than the QA; the mean (SD inter-observer/intra-observer PWV differences were -0.12(1.3/-0.04(0.4 for TT, 0.2(1.3/0.09(0.9 for XC, and 0.6(1.6/0.2(1.4 m/s for QA methods, respectively. The correlation coefficients (r for the inter-observer/intra-observer comparisons were 0.94/0.99, 0.88/0.94, and 0.83/0.92 for the TT, XC, and QA methods, respectively. The inter-scan reproducibility results showed low variability between the repeated

  5. Study of high field Nb3Sn superconducting dipoles: electrical insulation based made of ceramic and magnetic design

    International Nuclear Information System (INIS)

    In the framework of LHC upgrades, significant efforts are provided to design accelerator magnets using the superconducting alloy Nb3Sn, which allows to reach higher magnetic fields (≥12 T). The aim of this thesis is to propose new computation and manufacturing methods for high field Nb3Sn dipoles. A ceramic insulation, previously designed at CEA Saclay, has been tested for the first time on cables, in an accelerator magnet environment. Critical current measures, under magnetic field and mechanical stress, have been carried out in particular. With this test campaign, the current ceramic insulation has been shown to be too weak mechanically and the critical current properties are degraded. Then a study has been conducted, with the objective to improve the mechanical strength of the insulation and better distribute the stress inside the cable. Methods of magnetic design have also been proposed, in order to optimize the coils shape, while fulfilling constraints of field homogeneity, operational margins, forces minimization... Consequently, several optimization codes have been set up. They are based on new methods using analytical formulas. A 2D code has first been written for block designs. Then two 3D codes have been realized for the optimization of dipole ends. The former consists in modeling the coil with elementary blocs and the latter is based on a modeling of the superconducting cables with ribbons. These optimization codes allowed to propose magnetic designs for high field accelerator magnets. (author)

  6. High field magnetic behavior in Boron doped Fe2VAl Heusler alloys

    Science.gov (United States)

    Venkatesh, Ch.; Vasundhara, M.; Srinivas, V.; Rao, V. V.

    2016-11-01

    We have investigated the magnetic behavior of Fe2VAl1-xBx (x=0, 0.03, 0.06 and 0.1) alloys under high temperature and high magnetic field conditions separately. Although, the low temperature DC magnetization data for the alloys above x>0 show clear magnetic transitions, the zero field cooled (ZFC) and field cooled (FC) curves indicate the presence of spin cluster like features. Further, critical exponent (γ) deduced from the initial susceptibility above the Tc, does not agree with standard models derived for 3 dimensional long range magnetic systems. The deviation in γ values are consistent with the short range magnetic nature of these alloys. We further extend the analysis of magnetic behavior by carrying the magnetization measurements at high temperatures and high magnetic fields distinctly. We mainly emphasize the following observations; (i) The magnetic hysteresis loops show sharp upturns at lower fields even at 900 K for all the alloys. (ii) High temperature inverse susceptibility do not overlap until T=900 K, indicating the persistent short range magnetic correlations even at high temperatures. (iii) The Arrott's plot of magnetization data shows spontaneous moment (MS) for the x=0 alloy at higher magnetic fields which is absent at lower fields (<50 kOe), while the Boron doped samples show feeble MS at lower fields. The origin of this short range correlation is due to presence of dilute magnetic heterogeneous phases which are not detected from the X-ray diffraction method.

  7. Vol. 34 - Optimization of quench protection heater performance in high-field accelerator magnets through computational and experimental analysis

    CERN Document Server

    Salmi, Tiina

    2016-01-01

    Superconducting accelerator magnets with increasingly hi gh magnetic fields are being designed to improve the performance of the Large Hadron Collider (LHC) at CERN. One of the technical challenges is the magnet quench p rotection, i.e., preventing damage in the case of an unexpected loss of superc onductivity and the heat generation related to that. Traditionally this is d one by disconnecting the magnet current supply and using so-called protection he aters. The heaters suppress the superconducting state across a large fraction of the winding thus leading to a uniform dissipation of the stored energy. Preli minary studies suggested that the high-field Nb 3 Sn magnets under development for the LHC luminosity upgrade (HiLumi) could not be reliably protected using the existing heaters. In this thesis work I analyzed in detail the present state-of-the-art protection heater technology, aiming to optimize its perfo rmance and evaluate the prospects in high-field magnet protection. The heater efficiency analyses ...

  8. Safety implications of high-field MRI: actuation of endogenous magnetic iron oxides in the human body.

    Directory of Open Access Journals (Sweden)

    Jon Dobson

    Full Text Available BACKGROUND: Magnetic Resonance Imaging scanners have become ubiquitous in hospitals and high-field systems (greater than 3 Tesla are becoming increasingly common. In light of recent European Union moves to limit high-field exposure for those working with MRI scanners, we have evaluated the potential for detrimental cellular effects via nanomagnetic actuation of endogenous iron oxides in the body. METHODOLOGY: Theoretical models and experimental data on the composition and magnetic properties of endogenous iron oxides in human tissue were used to analyze the forces on iron oxide particles. PRINCIPAL FINDING AND CONCLUSIONS: Results show that, even at 9.4 Tesla, forces on these particles are unlikely to disrupt normal cellular function via nanomagnetic actuation.

  9. Windows on the Human Body – in Vivo High-Field Magnetic Resonance Research and Applications in Medicine and Psychology

    OpenAIRE

    Ewald Moser; Martin Meyerspeer; Fischmeister, Florian Ph. S.; Günther Grabner; Herbert Bauer; Siegfried Trattnig

    2010-01-01

    Analogous to the evolution of biological sensor-systems, the progress in “medical sensor-systems”, i.e., diagnostic procedures, is paradigmatically described. Outstanding highlights of this progress are magnetic resonance imaging (MRI) and spectroscopy (MRS), which enable non-invasive, in vivo acquisition of morphological, functional, and metabolic information from the human body with unsurpassed quality. Recent achievements in high and ultra-high field MR (at 3 and 7 Tesla) are described, an...

  10. A fast integral equation method for simulating high-field radio frequency coil arrays in magnetic resonance imaging

    International Nuclear Information System (INIS)

    A fast full-wave numerical approach was developed for simulating high-field multi-channel radio-frequency (RF) receive coil arrays in magnetic resonance imaging. To improve the efficiency, the impedance matrix was compressed by a multilevel adaptive cross approximation method. Furthermore, careful organization of multiple coil simulations was applied so that the impedance matrix associated with biological subjects is constructed and pre-conditioned only once. Numerical examples demonstrate the efficacy of the proposed approach for RF coil simulations.

  11. Fabrication and test results of a high field, Nb3Sn superconducting racetrack dipole magnet

    International Nuclear Information System (INIS)

    The LBNL Superconducting Magnet Program is extending accelerator magnet technology to the highest possible fields. A 1 meter long, racetrack dipole magnet, utilizing state-of-the-art Nb3Sn superconductor, has been built and tested. A record dipole filed of 14.7 Tesla has been achieved. Relevant features of the final assembly and tested results are discussed.

  12. A high-field pulsed magnet system for x-ray scattering studies in Voigt geometry

    CERN Document Server

    Islam, Zahirul; Ruff, Jacob P C; Das, Ritesh K; Trakhtenberg, Emil; Nojiri, Hiroyuki; Narumi, Yasuo; Canfield, Paul C

    2011-01-01

    We present a new pulsed-magnet system that enables x-ray single-crystal diffraction in addition to powder and spectroscopic studies in Voigt geometry. The apparatus consists of a large-bore solenoid, cooled by liquid nitrogen. A second independent closed-cycle cryostat is used for cooling samples near liquid helium temperatures. Pulsed magnetic fields up to ~30 T with a minimum of ~6 ms in total duration are generated by discharging a 40 kJ capacitor bank into the magnet coil. The unique characteristic of this instrument is the preservation of maximum scattering angle (~23.6 deg.) through the magnet bore by virtue of a novel double-funnel insert. This instrument would facilitate x-ray diffraction and spectroscopic studies that are impractical, if not impossible, to perform using conventional split-pair magnets and offers a practical solution for preserving optical access in future higher-field pulsed magnets.

  13. Halbach arrays consisting of cubic elements optimised for high field gradients in magnetic drug targeting applications

    International Nuclear Information System (INIS)

    A key challenge in the development of magnetic drug targeting (MDT) as a clinically relevant technique is designing systems that can apply sufficient magnetic force to actuate magnetic drug carriers at useful tissue depths. In this study an optimisation routine was developed to generate designs of Halbach arrays consisting of multiple layers of high grade, cubic, permanent magnet elements, configured to deliver the maximum pull or push force at a position of interest between 5 and 50 mm from the array, resulting in arrays capable of delivering useful magnetic forces to depths past 20 mm. The optimisation routine utilises a numerical model of the magnetic field and force generated by an arbitrary configuration of magnetic elements. Simulated field and force profiles of optimised arrays were evaluated, also taking into account the forces required for assembling the array in practice. The resultant selection for the array, consisting of two layers, was then constructed and characterised to verify the simulations. Finally the array was utilised in a set of in vitro experiments to demonstrate its capacity to separate and retain microbubbles loaded with magnetic nanoparticles against a constant flow. The optimised designs are presented as light-weight, inexpensive options for applying high-gradient, external magnetic fields in MDT applications. (paper)

  14. Halbach arrays consisting of cubic elements optimised for high field gradients in magnetic drug targeting applications.

    Science.gov (United States)

    Barnsley, Lester C; Carugo, Dario; Owen, Joshua; Stride, Eleanor

    2015-11-01

    A key challenge in the development of magnetic drug targeting (MDT) as a clinically relevant technique is designing systems that can apply sufficient magnetic force to actuate magnetic drug carriers at useful tissue depths. In this study an optimisation routine was developed to generate designs of Halbach arrays consisting of multiple layers of high grade, cubic, permanent magnet elements, configured to deliver the maximum pull or push force at a position of interest between 5 and 50 mm from the array, resulting in arrays capable of delivering useful magnetic forces to depths past 20 mm. The optimisation routine utilises a numerical model of the magnetic field and force generated by an arbitrary configuration of magnetic elements. Simulated field and force profiles of optimised arrays were evaluated, also taking into account the forces required for assembling the array in practice. The resultant selection for the array, consisting of two layers, was then constructed and characterised to verify the simulations. Finally the array was utilised in a set of in vitro experiments to demonstrate its capacity to separate and retain microbubbles loaded with magnetic nanoparticles against a constant flow. The optimised designs are presented as light-weight, inexpensive options for applying high-gradient, external magnetic fields in MDT applications. PMID:26458056

  15. The issues and tentative solutions for contrast-enhanced magnetic resonance imaging at ultra-high field strength.

    Science.gov (United States)

    Fries, Peter; Morelli, John N; Lux, Francois; Tillement, Olivier; Schneider, Günther; Buecker, Arno

    2014-01-01

    Magnetic resonance imaging (MRI) performed at ultra-high field strengths beyond 3 Tesla (T) has become increasingly prevalent in research and preclinical applications. As such, the inevitable clinical implementation of such systems lies on the horizon. The major benefit of ultra-high field MRI is the markedly increased signal-to-noise ratios achievable, enabling acquisition of MR images with simultaneously greater spatial and temporal resolution. However, at field strengths higher than 3 T, the efficacy of Gd(III)-based contrast agents is diminished due to decreased r1 relaxivity, somewhat limiting imaging of the vasculature and contrast-enhanced imaging of tumors. There have been extensive efforts to design new contrast agents with high r1 relaxivities based on macromolecular compounds or nanoparticles; however, the efficacy of these agents at ultra-high field strengths has not yet been proven. The aim of this review article is to provide an overview of the basic principles of MR contrast enhancement processes and to highlight the main factors influencing relaxivity. In addition, challenges and opportunities for contrast-enhanced MRI at ultra-high field strengths will be explored. Various approaches for the development of effective contrast agent molecules that are suitable for a broad spectrum of applied field strengths will be discussed in the context of the current literature.

  16. In vivo high field magnetic resonance imaging and spectroscopy of adult zebrafish

    NARCIS (Netherlands)

    Kabli, Samira

    2009-01-01

    This thesis contains the results of imaging of adult zebrafish by using different MR approaches. We present the first high resolution mMR images of adult zebrafish. To achieve high spatial resolution we used a magnetic field of 9.4T, in combination with strong magnetic field gradients (1000 mT/m) an

  17. High-field magnetic resonance imaging of the human temporal lobe

    Directory of Open Access Journals (Sweden)

    Luis M. Colon-Perez

    2015-01-01

    Conclusions: Fresh ex vivo MR imaging, along with tractography, revealed complex intra-temporal structural variation corresponding to neuronal cell body layers, dendritic fields, and axonal projection systems evident histologically. This is the first study to describe in detail the human temporal lobe structural organization using high-field MR imaging and tractography. By preserving the 3-dimensional structures of the hippocampus and surrounding structures, specific changes in anatomy may inform us about the changes that occur in TLE in relation to the disease process and structural underpinnings in epilepsy-related memory dysfunction.

  18. Pelvic endometriosis: a comparison between low-field (0.2 T) and high-field (1.5 T) magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Minaif, Karine; Ajzen, Sergio [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. of Imaging Diagnosis]. E-mail: kminaif@uol.com.br; Shigueoka, David Carlos; Minami, Cintia Cristina Satie; Sales, Danilo Moulin; Szejnfeld, Jacob [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. of Imaging Diagnosis. Unit of Abdomen; Ruano, Jose Maria Cordeiro [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. of General Gynecology. Sector of Videlaparoscopy; Noguti, Alberto Sinhiti [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. of General Gynecology

    2008-11-15

    Objective: to compare low-field (0.2 T) with high-field (1.5 T) magnetic resonance imaging in the assessment of pelvic endometriosis and adenomyosis. Materials and methods: twenty-seven female patients with clinically suspected endometriosis were prospectively evaluated by means of high-field and low-field magnetic resonance imaging. The reading of the images was performed by a single radiologist, initiating by the low-field, followed by the high-field images. High-field magnetic resonance imaging was utilized as the golden-standard. Results: among the 27 patients included in the present study, 18 (66.7%) had some type of lesion suggesting the presence of endometriosis demonstrated at high-field images. In 14 of these patients the diagnosis was correctly established by low-field magnetic resonance imaging. Endometriomas, tubal lesions, and endometriotic foci > 7 mm identified at the high-field images were also identified at low-field images with 100% accuracy, sensitivity and specificity. Among the nine patients diagnosed with adenomyosis by high-field images, eight were correctly diagnosed by low-field images with 88.9% accuracy, specificity and sensitivity. Conclusion: low-field magnetic resonance imaging demonstrated a low sensitivity in the detection of small endometriotic foci, high sensitivity in the detection of endometriomas and large endometriotic foci, and high accuracy in the detection of adenomyosis when compared with high-field magnetic resonance imaging. (author)

  19. A portable high-field pulsed magnet system for x-ray scattering studies.

    Energy Technology Data Exchange (ETDEWEB)

    Islam, Z.; Ruff, J.P.C.; Nojiri, H.; Matsuda, Y. H.; Ross, K. A.; Gaulin, B. D.; Qu, Z.; Lang, J. C. (X-Ray Science Division); ( PSC-USR); (McMaster Univ.); (Tohoku Univ.); (Tulane Univ.)

    2009-01-01

    We present a portable pulsed-magnet system for x-ray studies of materials in high magnetic fields (up to 30 T). The apparatus consists of a split-pair of minicoils cooled on a closed-cycle cryostat, which is used for x-ray diffraction studies with applied field normal to the scattering plane. A second independent closed-cycle cryostat is used for cooling the sample to near liquid helium temperatures. Pulsed magnetic fields (- 1 ms in total duration) are generated by discharging a configurable capacitor bank into the magnet coils. Time-resolved scattering data are collected using a combination of a fast single-photon counting detector, a multichannel scaler, and a high-resolution digital storage oscilloscope. The capabilities of this instrument are used to study a geometrically frustrated system revealing strong magnetostrictive effects in the spin-liquid state.

  20. Radio frequency probes for ultra-high field magnetic resonance imaging

    OpenAIRE

    Lee, Daniel James

    2011-01-01

    This thesis describes the design, construction and testing of a dome coil. The dome coil is hemispherical in shape and is intended to be used within a set of hemispherical gradient coils in a seven tesla magnetic resonance imaging magnet. The dome coil has eight independent elements and is designed to be used for parallel transmission and reception. It is shown that the dome coil produces less specific absorption rate than a conventional birdcage coil and is suitable for head imaging. A st...

  1. Magnetic resonance imaging of the chest: current and new applications, with an emphasis on pulmonology

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Marcel Koenigkam; Mauad, Fernando Marum, E-mail: marcelk46@yahoo.com.b [Universidade de Sao Paulo (HC/FMRP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Hospital das Clinicas; Elias Junior, Jorge; Muglia, Valdair Francisco [Universidade de Sao Paulo (FMRP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Secao de Radiologia

    2011-03-15

    The objective of the present review study was to present the principal applications of magnetic resonance imaging (MRI) of the chest, including the description of new techniques. Over the past decade, this method has evolved considerably because of the development of new equipment, including the simultaneous interconnection of phased-array multiple radiofrequency receiver coils and remote control of the table movement, in addition to faster techniques of image acquisition, such as parallel imaging and partial Fourier acquisitions, as well as the introduction of new contrast agents. All of these advances have allowed MRI to gain ground in the study of various pathologies of the chest, including lung diseases. Currently, MRI is considered the modality of choice for the evaluation of lesions in the mediastinum and in the chest wall, as well as of superior sulcus tumors. However, it can also facilitate the diagnosis of lung, pleural, and cardiac diseases, as well as of those related to the pulmonary vasculature. Pulmonary MRI angiography can be used in order to evaluate various pulmonary vascular diseases, and it has played an ever greater role in the study of thromboembolism. Because cardiac MRI allows morphological and functional assessment in the same test, it has also become part of the clinical routine in the evaluation of various cardiac diseases. Finally, the role of MRI has been extended to the identification and characterization of pulmonary nodules, the evaluation of airway diseases, and the characterization of pleural effusion. (author)

  2. Low and High Field Magnetic Resonance for in Vivo Analysis of Seeds

    Directory of Open Access Journals (Sweden)

    Thomas Neuberger

    2011-08-01

    Full Text Available Low field NMR has been successfully used for the evaluation of seed composition and quality, but largely only in crop species. We show here that 1.5T NMR provides a reliable means for analysing the seed lipid fraction present in a wide range of species, where both the seed size and lipid concentration differed by >10 fold. Little use of high field NMR has been made in seed research to date, even though it potentially offers many opportunities for studying seed development, metabolism and storage. Here we demonstrate how 17.5T and 20T NMR can be applied to image seed structure, and analyse lipid and metabolite distribution. We suggest that further technical developments in NMR/MRI will facilitate significant advances in our understanding of seed biology.

  3. Measuring remanence anisotropy of hematite in red beds: anisotropy of high-field isothermal remanence magnetization (hf-AIR)

    Science.gov (United States)

    Bilardello, Dario; Kodama, Kenneth P.

    2009-09-01

    The potential of using high-field anisotropy of isothermal remanence magnetization (hf-AIR) measurements for determining the origin of natural remanent magnetization in red beds and for identifying and correcting possible red-bed inclination shallowing was investigated for specimens of the Carboniferous Shepody Formation of New Brunswick and Nova Scotia, Canada. The technique makes it possible for a typical paleomagnetic laboratory to measure the remanence anisotropy of high-coercivity hematite. High-field (hf) AIR was used in conjunction with 100 mT alternating field (af) and 120°C thermal demagnetization to separate the contribution of hematite to the remanence anisotropy from that of magnetite/maghemite and goethite, respectively. A 5-T impulse DC magnetic field was used for the hf-AIR to reset the magnetic moment of high-coercivity hematite so that demagnetization between AIR orientations was not necessary. The ability of a 5-T field to reset the magnetization was tested by generating an isothermal remanent magnetization acquisition curve for hematite by using impulse DC magnetic fields up to 5 T in one orientation and followed by applying a field in the opposite direction at each step. Each field application was treated by 120°C heating and 100 mT af demagnetization before measurement. At 5 T, the difference between the magnetizations applied in opposite directions disappeared indicating that no magnetic memory persisted at this field strength. We performed a validity and reproducibility test of our hf-AIR measurement technique by measuring three specimens multiple times along two orthogonal coordinate systems. The method yielded highly reproducible results and, on rotating the specimen's coordinates, the fabric rotated by 90° as expected, showing that it is not an artifact of the technique. We also measured hf-AIR on samples that had previously been chemically demagnetized in 3N HCl to remove the secondary, chemically grown pigmentary hematite. The hf

  4. Invited Article: Development of high-field superconducting Ioffe magnetic traps

    Science.gov (United States)

    Yang, L.; Brome, C. R.; Butterworth, J. S.; Dzhosyuk, S. N.; Mattoni, C. E. H.; McKinsey, D. N.; Michniak, R. A.; Doyle, J. M.; Golub, R.; Korobkina, E.; O'Shaughnessy, C. M.; Palmquist, G. R.; Seo, P.-N.; Huffman, P. R.; Coakley, K. J.; Mumm, H. P.; Thompson, A. K.; Yang, G. L.; Lamoreaux, S. K.

    2008-03-01

    We describe the design, construction, and performance of three generations of superconducting Ioffe magnetic traps. The first two are low current traps, built from four racetrack shaped quadrupole coils and two solenoid assemblies. Coils are wet wound with multifilament NbTi superconducting wires embedded in epoxy matrices. The magnet bore diameters are 51 and 105mm with identical trap depths of 1.0T at their operating currents and at 4.2K. A third trap uses a high current accelerator-type quadrupole magnet and two low current solenoids. This trap has a bore diameter of 140mm and tested trap depth of 2.8T. Both low current traps show signs of excessive training. The high current hybrid trap, on the other hand, exhibits good training behavior and is amenable to quench protection.

  5. Research and Development of Nb3Sn Wires and Cables for High-Field Accelerator Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Barzi, Emanuela [Fermilab; Zlobin, Alexander V. [Fermilab

    2016-02-18

    The latest strategic plans for High Energy Physics endorse steadfast superconducting magnet technology R&D for future Energy Frontier Facilities. This includes 10 to 16 T Nb3Sn accelerator magnets for the luminosity upgrades of the Large Hadron Collider and eventually for a future 100 TeV scale proton-proton (pp) collider. This paper describes the multi-decade R&D investment in the Nb3Sn superconductor technology, which was crucial to produce the first reproducible 10 to 12 T accelerator-quality dipoles and quadrupoles, as well as their scale-up. We also indicate prospective research areas in superconducting Nb3Sn wires and cables to achieve the next goals for superconducting accelerator magnets. Emphasis is on increasing performance and decreasing costs while pushing the Nb3Sn technology to its limits for future pp colliders.

  6. Fiber optic quench detection via optimized Rayleigh Scattering in high-field YBCO accelerator magnets

    Energy Technology Data Exchange (ETDEWEB)

    Flanagan, Gene [North Carolina State Univ., Raleigh, NC (United States)

    2016-02-17

    Yttrium barium copper oxide (YBCO) coated conductors are known for their ability to operate in the superconducting state at relatively high temperatures, even above the boiling point of liquid nitrogen (77 K). When these same conductors are operated at lower temperatures, they are able to operate in much higher magnetic fields than traditional superconductors like NiTi or Nb3Sn. Thus, YBCO superconducting magnets are one of the primary options for generating the high magnetic fields needed for future high energy physics devices. Due to slow quench propagation, quench detection remains one of the primary limitations to YBCO magnets. Fiber optic sensing, based upon Rayleigh scattering, has the potential for spatial resolution approaching the wavelength of light, or very fast temporal resolution at low spatial resolution, and a continuum of combinations in between. This project has studied, theoretically and experimentally, YBCO magnets and Rayleigh scattering quench detection systems to demonstrate feasibility of the systems for YBCO quench protection systems. Under this grant an experimentally validated 3D quench propagation model was used to accurately define the acceptable range of spatial and temporal resolutions for effective quench detection in YBCO magnets and to evaluate present-day and potentially improved YBCO conductors. The data volume and speed requirements for quench detection via Rayleigh scattering required the development of a high performance fiber optic based quench detection/data acquisition system and its integration with an existing voltage tap/thermo-couple based system. In this project, optical fibers are tightly co-wound into YBCO magnet coils, with the fiber on top of the conductor as turn-to-turn insulation. Local changes in the temperature or strain of the conductor are sensed by the optical fiber, which is in close thermal and mechanical contact with the conductor. Intrinsic imperfections in the fiber reflect Rayleigh

  7. Progress in high field accelerator magnet development by the US LHC Accelerator Research Program

    CERN Document Server

    Sabbi, Gian Luca

    2011-01-01

    The maximum magnetic field available to guide and focus the proton beams will be the most important factor driving the design of the High Energy LHC. The US LHC Accelerator Research Program (LARP) is a collaboration of US National Laboratories aiming at demonstrating the feasibility of Nb3Sn magnet technology for application to future colliders. While LARP is primarily focused on the requirements of the High-Luminosity LHC (HL-LHC), it is also directly relevant to the High-Energy LHC (HE-LHC). Program results and future directions will be discussed.

  8. Design of HQ -- a High Field Large Bore Nb3Sn Quadrupole Magnet for LARP

    Energy Technology Data Exchange (ETDEWEB)

    Felice, H.; Ambrosio, G.; Anerella, M.; Bossert, R.; Caspi, S.; Cheng, D.; Dietderich, D.; Ferracin, P.; Ghosh, A. K.; Hafalia, R.; Hannaford, C. R.; Kashikhin, V.; Schmalze, J.; Prestemon, S.; Sabbi, G. L.; Wanderer, P.; Zlobin, A. V.

    2008-08-17

    In support of the Large Hadron Collider luminosity upgrade, a large bore (120 mm) Nb{sub 3}Sn quadrupole with 15 T peak coil field is being developed within the framework of the US LHC Accelerator Research Program (LARP). The 2-layer design with a 15 mm wide cable is aimed at pre-stress control, alignment and field quality while exploring the magnet performance limits in terms of gradient, forces and stresses. In addition, HQ will determine the magnetic, mechanical, and thermal margins of Nb{sub 3}Sn technology with respect to the requirements of the luminosity upgrade at the LHC.

  9. High Field Magnetization Studies of Low Dimensional Heisenberg S = 1/2 Antiferromagnets

    Science.gov (United States)

    Landee, C. P.; Turnbull, M. M.

    1998-03-01

    The magnetization curves of a number of low dimensional S=1/2 Heisenberg antiferromagnets have been determined in fields up to 30 tesla at low temperatures at the National High Magnetic Fields Laboratory. Materials studied include a family of 1D materials, based upon Cu(pyrazine)(NO_3)_2, 2D magnets consisting of pyrazine-bridged copper layers, and several spin ladders with singlet ground states. All of the magnetization data show upward curvature and are well described by T = 0 calculations based upon finite cluster models(Bonner and Fisher, Phys. Rev. A135, 640 (1964); Yang and Mutter, NANL cond-mat/9610092.). Chemical substitution on the pyrazine rings permits the variation of exchange constants by more than 25 percent for the family of well isolated chains. The spin ladder systems consist of ferromagnetic dimers weakly connected by antiferromagnetic intradimer interactions. Field induced transitions are seen at fields of less than one tesla for each of the three compounds.

  10. Development of high field magnets at the National Research Institute for Metals. Kinzoku zairyo gijutsu kenkyusho ni okeru kojikai magnet gun no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Kiyoshi, T.; Inoue, K.; Maeda, H. (National Research Inst. for Metals, Tsukuba (Japan))

    1993-06-20

    Sinece 1988, the Scince and Technology Agency has initiated the superconductor multicore project, which has a purpose of the versatile study on the high temperature superconducting materials of the oxide series. The National Research Institute for Metals is in charge of 5 cores out of them, and in the performance evaluation core which is one of them, the development of each kind of the high field magnets is being advanced for evaluating the characteristics under the high magnetic field. As the magnets, including the 40T class hybrid magnet which generates the steady state magnetic field of 40T, the superconducting magnet of 20T with a large diameter which generates the magnetic field over 20T with a superconductor, the condenser bank system for the pulse magnet to generate the pulse magnetic field up to 80T, and the ultra-precise magnet system which generates the magnetic field with a high uniformity will be consolidated. Keeping pace with a removal of the National Research Institute for Metals to Tsukuba, the construction of the strong magnetic field station is being advanced in the Sakura area. These several kinds of magnets are scheduled to be used in turn for the international joint study. 33 refs., 5 figs., 4 tabs.

  11. NANOSCOPIC MOLECULAR CLUSTER V15: HIGH-FIELD EPR AND MAGNETIZATION AT ULTRA-LOW TEMPERATURES

    Directory of Open Access Journals (Sweden)

    Boris Tsukerblat

    2007-06-01

    Full Text Available n this paper we give a short overview of our efforts in the understanding of the magnetic properties of the fascinating nanoscopic cluster K6[VIV15As6O42(H2O]·8H2O (hereafter V15 exhibiting layers of magnetization. We analyze EPR and adiabatic magnetization of the V15 cluster with a triangular VIV3 array causing spin frustration. A model for V15 includes isotropic and antisymmetric (AS exchange interactions in the general form compatible with the trigonal symmetry. Orientation of the AS vector (but not only its absolute value is shown to play an important physical role in spin-frustrated systems. We were able to reach perfect fit to the experimental data on the stepwise dependence of magnetization vs. field at ultra-low temperatures. Furthermore, it was possible for the first time to estimate precisely two components of the AS vector coupling constant, namely, in-plane component and the perpendicular part. We show that only intramultiplet transitions in EPR are allowed when the vector of AS exchange is normal to the plane of vanadium triangle, meanwhile the in-plane part of AS exchange gives rise to a series of weak intermultiplet transitions. Experimental data on high-frequency EPR of V15 at low temperatures are discussed. The spin-vibronic effects in trimeric spin frustrated clusters are also studied and an important role of the interplay between the AS exchange and Jahn-Teller interaction is revealed. The results clarify the concept of spin-frustration in view of its magnetic and spectroscopic manifestations in metal clusters.

  12. Critical current and instability threshold measurement of Nb$_{3}$ Sn cables for high field accelerator magnets

    CERN Document Server

    Ambrosio, Giorgio; Bartlett, S E; Barzi, E; Denarié, C H; Dietderich, D R; Ghosh, Arup K; Verweij, A P; Zlobin, A V

    2005-01-01

    Rutherford-type cables made of high critical current Nb/sub 3/Sn strands are being used in several laboratories for developing new generation superconducting magnets for present and future accelerators and upgrades. Testing of cable short samples is an important part of these R&D programs and the instability problem found in some short model magnets at Fermilab made these tests even more significant. Fermilab in collaboration with BNL, CERN and LBNL has developed sample holders and sample preparation infrastructure and procedures for testing Nb/sub 3/Sn cable short samples at BNL and CERN test facilities. This paper describes the sample holders, sample preparation and instrumentation, and test results. Several samples made of MJR or PIT strands 1 mm in diameter have been tested. Some samples were unstable (i.e. quenched at low transport currents) at low fields and reached the critical surface at higher fields.

  13. High-field (9.4 T) ~1H magnetic resonance microscopy of mouse brain

    Institute of Scientific and Technical Information of China (English)

    丁广良; 胡红兵; 李丽云; 叶朝辉

    1997-01-01

    The FLASH and STEAM pulse sequences were used to perform the microimaging and localized spectroscopy of brain of living and dead mice, respectively. The phase-shift presaturation approach was used to sup-press water NMR signal. The experimental results show that the differences in localized spectra and MR images of brain between live and dead mice can be observed by means of magnetic resonance microscopy.

  14. Demountable low stress high field toroidal field magnet system for tokamak fusion reactors

    International Nuclear Information System (INIS)

    A new type of superconducting magnet system for large fusion reactors is described. Instead of winding large planar or multi-axis coils, as has been proposed in previous fusion reactor designs, the superconducting coils are made by joining together several prefabricated conductor sections. The joints can be unmade and sections removed if they fail. Conductor sections can be made at a factory and shipped to the reactor site for assembly. The conductor stress level in the assembled coil can be kept small by external support of the coil at a number of points along its perimeter, so that the magnetic forces are transmitted to an external warm reinforcement structure. This warm reinforcement structure can also be the primary containment for the fusion reactor, constructed similar to a PCRV (Prestressed Concrete Reactor Vessel) used in fission reactors. Low thermal conductivity, high strength supports are used to transfer the magnetic forces to the external reinforcement through a hydraulic system. The hydraulic supports are movable and can be programmed to accommodate thermal contraction and to minimize stress in the superconducting coil. (author)

  15. High-field magnetic phase transitions and spin excitations in magnetoelectric LiNiPO4

    DEFF Research Database (Denmark)

    Toft-Petersen, Rasmus; Jensen, Jens; Jensen, Thomas Bagger Stibius;

    2011-01-01

    The magnetically ordered phases and spin dynamics of magnetoelectric LiNiPO4 have been studied in fields up to 17.3 T along the c axis. Using neutron diffraction, we show that a previously proposed linearly polarized incommensurate (IC) structure exists only for temperatures just below the Neel...... temperature T-N. The ordered IC structure at the lowest temperatures is shown instead to be an elliptically polarized canted spiral for fields larger than 12 T. The transition between the two IC phases is of second order and takes place about 2 K below T-N. For mu H-0 > 16 T and temperatures below 10 K......, the spiral structure is found to lock in to a period of five crystallographic unit cells along the b axis. Based on the neutron-diffraction data, combined with detailed magnetization measurements along all three crystallographic axes, we establish the magnetic phase diagrams for fields up to 17.3 T along c...

  16. High-field magnetic resonance imaging of brain iron: birth of a biomarker?

    Science.gov (United States)

    Schenck, John F; Zimmerman, Earl A

    2004-11-01

    The brain has an unusually high concentration of iron, which is distributed in an unusual pattern unlike that in any other organ. The physiological role of this iron and the reasons for this pattern of distribution are not yet understood. There is increasing evidence that several neurodegenerative diseases are associated with altered brain iron metabolism. Understanding these dysmetabolic conditions may provide important information for their diagnosis and treatment. For many years the iron distribution in the human brain could be studied effectively only under postmortem conditions. This situation was changed dramatically by the finding that T2-weighted MR imaging at high field strength (initially 1.5 T) appears to demonstrate the pattern of iron distribution in normal brains and that this imaging technique can detect changes in brain iron concentrations associated with disease states. Up to the present time this imaging capability has been utilized in many research applications but it has not yet been widely applied in the routine diagnosis and management of neurodegenerative disorders. However, recent advances in the basic science of brain iron metabolism, the clinical understanding of neurodegenerative diseases and in MRI technology, particularly in the availability of clinical scanners operating at the higher field strength of 3 T, suggest that iron-dependent MR imaging may soon provide biomarkers capable of characterizing the presence and progression of important neurological disorders. Such biomarkers may be of crucial assistance in the development and utilization of effective new therapies for Alzheimer's and Parkinson's diseases, multiple sclerosis and other iron-related CNS disorders which are difficult to diagnose and treat.

  17. Functional magnetic resonance imaging with ultra-high fields; Funktionelle Magnetresonanztomographie bei ultrahohen Feldern

    Energy Technology Data Exchange (ETDEWEB)

    Windischberger, C.; Schoepf, V.; Sladky, R.; Moser, E. [Medizinische Universitaet Wien, Exzellenzzentrum Hochfeld-MR, Wien (Austria); Medizinische Universitaet Wien, Zentrum fuer Medizinische Physik und Biomedizinische Technik, Wien (Austria); Fischmeister, F.P.S. [Medizinische Universitaet Wien, Exzellenzzentrum Hochfeld-MR, Wien (Austria); Universitaet Wien, Fakultaet fuer Psychologie, Wien (Austria)

    2010-02-15

    Functional magnetic resonance imaging (fMRI) is currently the primary method for non-invasive functional localization in the brain. With the emergence of MR systems with field strengths of 4 Tesla and above, neuronal activation may be studied with unprecedented accuracy. In this article we present different approaches to use the improved sensitivity and specificity for expanding current fMRT resolution limits in space and time based on several 7 Tesla studies. In addition to the challenges that arise with ultra-high magnetic fields possible solutions will be discussed. (orig.) [German] Die funktionelle Magnetresonanztomographie (fMRT) stellt zurzeit die wichtigste Methode zur nichtinvasiven Funktionslokalisation im Gehirn dar. Mit der Verfuegbarkeit von MRT-Geraeten mit Magnetfeldstaerken von 4 Tesla (T) und darueber ergeben sich neue Moeglichkeiten, mittels fMRT die neuronale Aktivitaet in bislang unerreichter Genauigkeit zu untersuchen. In diesem Artikel zeigen wir anhand mehrerer Studien bei 7 T, in wieweit die Zugewinne an Sensitivitaet und Spezifitaet verwendet werden koennen, um die bisherigen Grenzen der fMRT-Aufloesung in raeumlicher und zeitlicher Hinsicht auszuweiten. Die neuen Herausforderungen, die mit dem Schritt zu ultrahohen Magnetfeldern einhergehen, werden dabei ebenso diskutiert wie moegliche Ansaetze zu deren Loesung. (orig.)

  18. Estimation of the Required Amount of Superconductors for High-field Accelerator Dipole Magnets

    CERN Document Server

    Schwerg, N

    2007-01-01

    The coil size and the corresponding amount of superconducting material that is used during the design process of a magnet cross-section have direct impacts on the overall magnet cost. It is therefore of interest to estimate the minimum amount of conductors needed to reach the defined field strength before a detailed design process starts. Equally, it is useful to evaluate the efficiency of a given design by calculating the amount of superconducting cables that are used to reach the envisaged main field by simple rule. To this purpose, the minimum amount of conductors for the construction of a dipole of given main field strength and aperture size is estimated taking the actual critical current density of the used strands into account. Characteristic curves applicable for the NED Nb3Sn strand specification are given and some of the recently studied different dipole configurations are compared. Based on these results, it is shown how the required amount of conductors changes due to the iron yoke contribution and...

  19. Development of superconductors for applications in high-field, high-current-density magnets for fusion research

    International Nuclear Information System (INIS)

    The development of large-bore, high-field magnets for fusion energy applications requires a system approach to both magnet and conductor design. At Lawrence Livermore National Laboratory (LLNL), the criteria used to choose superconductors include: strain tolerance, radiation tolerance, heat removal, stability, fabricability, and cost. We report on the performance of industrially produced, prototype, Ti-modified Nb3Sn wires developed with LLNL support. Wire performance characteristics evaluated include critical current as a function of magnetic field, temperature, and applied strain. Tests were performed to determine how this performance translates to the performance of a cable-in-conduit conductor system using this wire. An alternative to Nb3Sn superconductors is NbN, which is strain and radiation insensitive. We report preliminary efforts to produce multifilamentary NbN conductors by liquid-metal infiltration of NbN-coated, high-strength fibers. In addition, we discuss the fabrication of multifilamentary NbN conductors and their possible impact on magnet design

  20. Characterization of a dielectric phantom for high-field magnetic resonance imaging applications

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Qi, E-mail: Qi.Duan@nih.gov; Duyn, Jeff H.; Gudino, Natalia; Zwart, Jacco A. de; Gelderen, Peter van [Advanced MRI Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892 (United States); Sodickson, Daniel K.; Brown, Ryan [The Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, New York 10016 (United States)

    2014-10-15

    Purpose: In this work, a generic recipe for an inexpensive and nontoxic phantom was developed within a range of biologically relevant dielectric properties from 150 MHz to 4.5 GHz. Methods: The recipe includes deionized water as the solvent, NaCl to primarily control conductivity, sucrose to primarily control permittivity, agar–agar to gel the solution and reduce heat diffusivity, and benzoic acid to preserve the gel. Two hundred and seventeen samples were prepared to cover the feasible range of NaCl and sucrose concentrations. Their dielectric properties were measured using a commercial dielectric probe and were fitted to a 3D polynomial to generate a recipe describing the properties as a function of NaCl concentration, sucrose concentration, and frequency. Results: Results indicated that the intuitive linear and independent relationships between NaCl and conductivity and between sucrose and permittivity are not valid. A generic polynomial recipe was developed to characterize the complex relationship between the solutes and the resulting dielectric values and has been made publicly available as a web application. In representative mixtures developed to mimic brain and muscle tissue, less than 2% difference was observed between the predicted and measured conductivity and permittivity values. Conclusions: It is expected that the recipe will be useful for generating dielectric phantoms for general magnetic resonance imaging (MRI) coil development at high magnetic field strength, including coil safety evaluation as well as pulse sequence evaluation (including B{sub 1}{sup +} mapping, B{sub 1}{sup +} shimming, and selective excitation pulse design), and other non-MRI applications which require biologically equivalent dielectric properties.

  1. Can Images Obtained With High Field Strength Magnetic Resonance Imaging Reduce Contouring Variability of the Prostate?

    International Nuclear Information System (INIS)

    Purpose: The objective of this study is to determine whether there is less contouring variability of the prostate using higher-strength magnetic resonance images (MRI) compared with standard MRI and computed tomography (CT). Methods and Materials: Forty patients treated with prostate brachytherapy were accrued to a prospective study that included the acquisition of 1.5-T MR and CT images at specified time points. A subset of 10 patients had additional 3.0-T MR images acquired at the same time as their 1.5-T MR scans. Images from each of these patients were contoured by 5 radiation oncologists, with a random subset of patients repeated to quantify intraobserver contouring variability. To minimize bias in contouring the prostate, the image sets were placed in folders in a random order with all identifiers removed from the images. Results: Although there was less interobserver contouring variability in the overall prostate volumes in 1.5-T MRI compared with 3.0-T MRI (p < 0.01), there was no significant differences in contouring variability in the different regions of the prostate between 1.5-T MRI and 3.0-T MRI. MRI demonstrated significantly less interobserver contouring variability in both 1.5-T and 3.0-T compared with CT in overall prostate volumes (p < 0.01, p = 0.01), with the greatest benefits being appreciated in the base of the prostate. Overall, there was less intraobserver contouring variability than interobserver contouring variability for all of the measurements analyzed. Conclusions: Use of 3.0-T MRI does not demonstrate a significant improvement in contouring variability compared with 1.5-T MRI, although both magnetic strengths demonstrated less contouring variability compared with CT.

  2. Effects of surgical implants on high-field magnetic resonance images of the normal canine stifle.

    Science.gov (United States)

    David, F H; Grierson, J; Lamb, C R

    2012-01-01

    To determine the effect of surgical implants on the depiction of canine stifle anatomy in magnetic resonance (MR) images, three canine cadaver limbs were imaged at 1.5 T before and after tibial plateau leveling osteotomy (TPLO), tibial tuberosity advancement (TTA), and extra-capsular stabilization (ECS), respectively. Susceptibility artifacts associated with implants were identified in MR images as a signal void and/or signal misregistration, which obscured or distorted the anatomy. Using the preoperative images as a reference, articular structures of the stifle in postoperative images were graded using an ordinal scale to describe to what degree each anatomic structure could be evaluated for clinical purposes. The TPLO implant, which contains ferromagnetic stainless steel, produced marked susceptibility artifacts that obscured or distorted most stifle anatomy. The titanium alloy TTA implants and the stainless steel crimps used for ECS produced susceptibility artifacts that mainly affected the lateral aspect of the stifle, but allowed the cruciate ligaments and medial meniscus to be evaluated satisfactorily. Susceptibility artifact was significantly less marked in images obtained using turbo spin-echo (TSE) sequences than in sequences employing spectral fat saturation. Clinical MR imaging of canine stifles containing certain metallic implants is feasible using TSE sequences without fat saturation. PMID:22372640

  3. Brain-heart interactions: challenges and opportunities with functional magnetic resonance imaging at ultra-high field.

    Science.gov (United States)

    Chang, Catie; Raven, Erika P; Duyn, Jeff H

    2016-05-13

    Magnetic resonance imaging (MRI) at ultra-high field (UHF) strengths (7 T and above) offers unique opportunities for studying the human brain with increased spatial resolution, contrast and sensitivity. However, its reliability can be compromised by factors such as head motion, image distortion and non-neural fluctuations of the functional MRI signal. The objective of this review is to provide a critical discussion of the advantages and trade-offs associated with UHF imaging, focusing on the application to studying brain-heart interactions. We describe how UHF MRI may provide contrast and resolution benefits for measuring neural activity of regions involved in the control and mediation of autonomic processes, and in delineating such regions based on anatomical MRI contrast. Limitations arising from confounding signals are discussed, including challenges with distinguishing non-neural physiological effects from the neural signals of interest that reflect cardiorespiratory function. We also consider how recently developed data analysis techniques may be applied to high-field imaging data to uncover novel information about brain-heart interactions.

  4. Brain-heart interactions: challenges and opportunities with functional magnetic resonance imaging at ultra-high field.

    Science.gov (United States)

    Chang, Catie; Raven, Erika P; Duyn, Jeff H

    2016-05-13

    Magnetic resonance imaging (MRI) at ultra-high field (UHF) strengths (7 T and above) offers unique opportunities for studying the human brain with increased spatial resolution, contrast and sensitivity. However, its reliability can be compromised by factors such as head motion, image distortion and non-neural fluctuations of the functional MRI signal. The objective of this review is to provide a critical discussion of the advantages and trade-offs associated with UHF imaging, focusing on the application to studying brain-heart interactions. We describe how UHF MRI may provide contrast and resolution benefits for measuring neural activity of regions involved in the control and mediation of autonomic processes, and in delineating such regions based on anatomical MRI contrast. Limitations arising from confounding signals are discussed, including challenges with distinguishing non-neural physiological effects from the neural signals of interest that reflect cardiorespiratory function. We also consider how recently developed data analysis techniques may be applied to high-field imaging data to uncover novel information about brain-heart interactions. PMID:27044994

  5. Manufacture and Testing of a High Field Gradient Magnetic Fractionation System for Quantitative Detection of Plasmodium falciparum Gametocytes

    Science.gov (United States)

    Karl, Stephan; Woodward, Robert C.; Davis, Timothy M. E.; St. Pierre, Tim G.

    2010-12-01

    Plasmodium falciparum is the most dangerous of the human malaria parasite species and accounts for millions of clinical episodes of malaria each year in tropical countries. The pathogenicity of Plasmodium falciparum is a result of its ability to infect erythrocytes where it multiplies asexually over 48 h or develops into sexual forms known as gametocytes. If sufficient male and female gametocytes are taken up by a mosquito vector, it becomes infectious. Therefore, the presence and density of gametocytes in human blood is an important indicator of human-to-mosquito transmission of malaria. Recently, we have shown that high field gradient magnetic fractionation improves gametocyte detection in human blood samples. Here we present two important new developments. Firstly we introduce a quantitative approach to replace the previous qualitative method and, secondly, we describe a novel method that enables cost-effective production of the magnetic fractionation equipment required to carry out gametocyte quantification. We show that our custom-made magnetic fractionation equipment can deliver results with similar sensitivity and convenience but for a small fraction of the cost.

  6. Windows on the Human Body – in Vivo High-Field Magnetic Resonance Research and Applications in Medicine and Psychology

    Directory of Open Access Journals (Sweden)

    Ewald Moser

    2010-06-01

    Full Text Available Analogous to the evolution of biological sensor-systems, the progress in “medical sensor-systems”, i.e., diagnostic procedures, is paradigmatically described. Outstanding highlights of this progress are magnetic resonance imaging (MRI and spectroscopy (MRS, which enable non-invasive, in vivo acquisition of morphological, functional, and metabolic information from the human body with unsurpassed quality. Recent achievements in high and ultra-high field MR (at 3 and 7 Tesla are described, and representative research applications in Medicine and Psychology in Austria are discussed. Finally, an overview of current and prospective research in multi-modal imaging, potential clinical applications, as well as current limitations and challenges is given.

  7. Magnetic resonance imaging of the chest in the evaluation of cancer patients: state of the art

    Directory of Open Access Journals (Sweden)

    Marcos Duarte Guimaraes

    2015-02-01

    Full Text Available Magnetic resonance imaging (MRI has several advantages in the evaluation of cancer patients with thoracic lesions, including involvement of the chest wall, pleura, lungs, mediastinum, esophagus and heart. It is a quite useful tool in the diagnosis, staging, surgical planning, treatment response evaluation and follow-up of these patients. In the present review, the authors contextualize the relevance of MRI in the evaluation of thoracic lesions in cancer patients. Considering that MRI is a widely available method with high contrast and spatial resolution and without the risks associated with the use of ionizing radiation, its use combined with new techniques such as cine-MRI and functional methods such as perfusion- and diffusion-weighted imaging may be useful as an alternative tool with performance comparable or complementary to conventional radiological methods such as radiography, computed tomography and PET/CT imaging in the evaluation of patients with thoracic neoplasias.

  8. Recent progress towards developing a high field, high-T(sub c) superconducting magnet for magnetic suspension and balance systems

    Science.gov (United States)

    Derochemont, L. Pierre; Oakes, Carlton E.; Squillante, Michael R.; Duan, Hong-Min; Hermann, Allen M.; Andrews, Robert J.; Poeppel, Roger B.; Maroni, Victor A.; Carlberg, Ingrid A.; Kelliher, Warren C.

    1992-01-01

    This paper reviews superconducting magnets and high T(sub c) superconducting oxide ceramic materials technology to identify areas of fundamental impasse to the fabrication of components and devices that tap what are believed to be the true potential of these new materials. High T(sub c) ceramics pose problems in fundamentally different areas which need to be solved unlike low T(sub c) materials. The authors map out an experimental plan designed to research process technologies which, if suitably implemented, should allow these deficiencies to be solved. Finally, assessments are made of where and on what regimes magnetic system designers should focus their attention to advance the practical development of systems based on these new materials.

  9. Non-selective Refocusing Pulse Design in Parallel Transmission for Magnetic Resonance Imaging of the Human Brain at Ultra High Field

    OpenAIRE

    Massire, Aurélien,

    2014-01-01

    In Magnetic Resonance Imaging (MRI), the increase of the static magnetic field strength is used to provide in theory a higher signal-to-noise ratio, thereby improving the overall image quality. The purpose of ultra-high-field MRI is to achieve a spatial image resolution sufficiently high to be able to distinguish structures so fine that they are currently impossible to view in a non-invasive manner. However, at such static magnetic fields strengths, the wavelength of the electromagnetic waves...

  10. Functionality of veterinary identification microchips following low- (0.5 tesla) and high-field (3 tesla) magnetic resonance imaging.

    Science.gov (United States)

    Piesnack, Susann; Frame, Mairi E; Oechtering, Gerhard; Ludewig, Eberhard

    2013-01-01

    The ability to read patient identification microchips relies on the use of radiofrequency pulses. Since radiofrequency pulses also form an integral part of the magnetic resonance imaging (MRI) process, the possibility of loss of microchip function during MRI scanning is of concern. Previous clinical trials have shown microchip function to be unaffected by MR imaging using a field strength of 1 Tesla and 1.5. As veterinary MRI scanners range widely in field strength, this study was devised to determine whether exposure to lower or higher field strengths than 1 Tesla would affect the function of different types of microchip. In a phantom study, a total of 300 International Standards Organisation (ISO)-approved microchips (100 each of three different types: ISO FDX-B 1.4 × 9 mm, ISO FDX-B 2.12 × 12 mm, ISO HDX 3.8 × 23 mm) were tested in a low field (0.5) and a high field scanner (3.0 Tesla). A total of 50 microchips of each type were tested in each scanner. The phantom was composed of a fluid-filled freezer pack onto which a plastic pillow and a cardboard strip with affixed microchips were positioned. Following an MRI scan protocol simulating a head study, all of the microchips were accurately readable. Neither 0.5 nor 3 Tesla imaging affected microchip function in this study.

  11. Preoperative 3T high field blood oxygen level dependent functional magnetic resonance imaging for glioma involving sensory cortical areas

    Institute of Scientific and Technical Information of China (English)

    LI Shao-wu; WANG Jiang-fei; JIANG Tao; LI Shou-wei; ZHANG Wen-bo; LI Zi-xiao; ZHANG Zhong; DAI Jian-ping; WANG Zhong-cheng

    2010-01-01

    Background Localization of sensory cortical areas during the operation is essential to preserve the sensory function.Intraoperative direct electrostimulation under awake anesthesia is the golden standard but time-consuming. We applied 3T high field blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to identify the relationship between glioma and cortical sensory areas preoperatively and to guide intraoperative direct electrostimulation for quick and precise localization.Methods Five glioma patients with sensory cortex involvement by or next to the lesion had preoperative BOLD fMRI to determine the spatial relationship of cortical sensory areas to the tumours. Bilateral hand opposite movement was performed by these patients for fMRI. Precentral and postcentral gyri were identified by electrical stimulation during the operation. Karnofsky Performance Status scores of the patients' pre- and postoperative and the role of BOLD fMRI were evaluated.Results The cortical sensory areas were all activated in five glioma patients involving postcentral gyrus areas by BOLDf MRI with bilateral hand opposite movement. The detected activation areas corresponded with the results from cortical electrical stimulation.Conclusions The relationship between cortical sensory areas and tumour can be accurately shown by BOLD fMRI before operation. And the information used to make the tumour resection could obtain good clinical results.

  12. Development of the Nb3Sn Rutherford Cable for the EuCARD High Field Dipole Magnet FRESCA2

    CERN Document Server

    Oberli, l

    2013-01-01

    This paper reports on the development of the Nb3Sn Rutherford cable for the EuCARD high field dipole magnet FRESCA2 designed to achieve a central field of 13 T at 4.2 K in a 100 mm bore. The FRESCA2 cable is rectangular and made of 40 strands of 1.0 mm diameter. The cable shall be able to carry a current of 15.7 kA at 4.2 K in a field of 15 T. In the first stage of cable development, focus was put on the cable parameters (cable width, cable mid-thickness and pitch length) to provide a cable made with Nb3Sn PIT strands achieving both a minimal critical current reduction of the strand during cabling and a good mechanical stability of the cable for coil winding. In the second stage of cable development, the cable was produced with Nb3Sn RRP strands. The cables, which were produced following an iterative process, were characterized and the results of the critical current measurements of extracted strands are discussed together with the cabling parameters and the type of strand.

  13. Magnetic properties of Zn doped Co2Y hexaferrite by using high-field Mössbauer spectroscopy

    International Nuclear Information System (INIS)

    The polycrystalline samples of Ba2Co2−xZnxFe12O22 (x = 0.5, 1.0, 1.5) were synthesized by using solid-state-reaction method. From the XRD patterns, analyzed by Rietveld refinement, the prepared samples are found to be single-phased with rhombohedral structure (R-3m). The magnetic properties of samples were investigated with vibrating sample magnetometer, and high-field Mössbauer spectrometer. From the zero-field-cooled curves under 100 Oe between 4.2 and 740 K, we observe that the samples show spin transition from helicalmagnetic to ferrimagnetic order. With increasing Zn ion concentration, the spin transition temperature (Ts) and Curie temperature (TC) decrease linearly. We have obtained Zero-field Mössbauer spectra of all samples at various temperatures ranging from 4.2 to 650 K, and analyzed the spectra below TC as six-sextets for Fe sites. From the temperature dependence of hyperfine field (Hhf), we have noticed an abrupt change in Hhf at Ts. In addition, Mössbauer spectra of all samples at 4.2 K were taken with applied field ranging from 0 to 50 kOe, indicating the canting angle between applied field and Hhf decreased with increasing Zn concentration

  14. Cardiovascular magnetic resonance of myocardial infarction after blunt chest trauma: a heartbreaking soccer-shot

    OpenAIRE

    Fogarassy Peter; Maunz Martin; Beck Torsten; Baccouche Hannibal; Beyer Martin

    2009-01-01

    Abstract Cardiac injury occasionally occurs as a result of blunt chest trauma. Most cardiac complications in chest trauma are due to myocardial contusion rather than direct damage to the coronary arteries. However, traumatic coronary injury has been reported, and a variety of underlying pathophysiological mechanisms have been proposed. We present a 26 year old patient presenting with an acute coronary syndrome as a consequence of a soccer-shot impact to the chest. CMR showed apical inferior i...

  15. A multireader reliability study comparing conventional high-field magnetic resonance imaging with extremity low-field MRI in rheumatoid arthritis

    DEFF Research Database (Denmark)

    Bird, Paul; Ejbjerg, Bo; Lassere, Marissa;

    2007-01-01

    The use of extremity low-field magnetic resonance imaging (E-MRI) is increasing, but relatively few data exist on its reproducibility and accuracy in comparison with high-field MRI, especially for multiple readers. The aim of this multireader exercise of rheumatoid arthritis wrist and metacarpoph...

  16. A multireader reliability study comparing conventional high-field magnetic resonance imaging with extremity low-field MRI in rheumatoid arthritis

    DEFF Research Database (Denmark)

    Bird, Paul; Ejbjerg, Bo; Lassere, Marissa;

    2007-01-01

    The use of extremity low-field magnetic resonance imaging (E-MRI) is increasing, but relatively few data exist on its reproducibility and accuracy in comparison with high-field MRI, especially for multiple readers. The aim of this multireader exercise of rheumatoid arthritis wrist...

  17. Cine magnetic resonance imaging, computed tomography and ultrasonography in the evaluation of chest wall invasion of lung cancer

    International Nuclear Information System (INIS)

    To assess the usefulness of cine-magnetic resonance imaging (cine-MRI) in the evaluation of chest wall invasion, we compared the results of cine-MRI with those of computed tomography (CT) and ultrasonography (US). Eleven patients were examined who had no pain and who were difficult to diagnose by routine examinations. MRI was performed with a Magnetom SP/4000, 1.5T unit (Siemens, Germany). For cine imaging, continuous turbo-FLUSH (ultra fast low angle shot) images were obtained at an orthogonal section to the chest wall during slow deep breathing. A CT scan was performed using a TCT 900S or Super Helix (Toshiba, Japan) at 1 cm intervals, with section thicknesses of 1 cm throughout the entire chest. US was performed with a model SSA-270A (Toshiba, Japan) with 7.5-MHz linear array scanners (PLF-705S; Toshiba, Japan). Sensitivity, specificity and accuracy were 67%, 75% and 73% for cine MRI, 67%, 63% and 64% for CT, 33%, 75% and 64% for US, respectively. These results indicate that cine MRI is potentially useful for the diagnosis of chest wall invasion of lung cancer. (author)

  18. An Ultra-High Field Magnetic Resonance Spectroscopy Study of Post Exercise Lactate, Glutamate and Glutamine Change in the Human Brain

    OpenAIRE

    Dennis, Andrea; Thomas, Adam G.; Rawlings, Nancy B.; Near, Jamie; Nichols, Thomas E.; Clare, Stuart; Johansen-Berg, Heidi; Stagg, Charlotte J.

    2015-01-01

    During strenuous exercise there is a progressive increase in lactate uptake and metabolism into the brain as workload and plasma lactate levels increase. Although it is now widely accepted that the brain can metabolize lactate, few studies have directly measured brain lactate following vigorous exercise. Here, we used ultra-high field magnetic resonance spectroscopy of the brain to obtain static measures of brain lactate, as well as brain glutamate and glutamine after vigorous exercise. The a...

  19. Cardiovascular magnetic resonance of myocardial infarction after blunt chest trauma: a heartbreaking soccer-shot

    Directory of Open Access Journals (Sweden)

    Fogarassy Peter

    2009-10-01

    Full Text Available Abstract Cardiac injury occasionally occurs as a result of blunt chest trauma. Most cardiac complications in chest trauma are due to myocardial contusion rather than direct damage to the coronary arteries. However, traumatic coronary injury has been reported, and a variety of underlying pathophysiological mechanisms have been proposed. We present a 26 year old patient presenting with an acute coronary syndrome as a consequence of a soccer-shot impact to the chest. CMR showed apical inferior infarction, as well as multiple small septal lesions which were presumed to have resulted from embolization. The culprit lesion was a proximal 75% LAD stenosis with a prominent plaque-rupture and thrombus-formation, and the distal LAD was occluded by thromboembolic material.

  20. Limits of NbTi and Nb3Sn, and Development of W&R Bi-2212 High Field Accelerator Magnets

    OpenAIRE

    Godeke, A; Cheng, D.; Dietderich, D. R.; Ferracin, P.; Prestemon, S. O.; Sabbi, G.; Scanlan, R.M.

    2008-01-01

    NbTi accelerator dipoles are limited to magneticfields (H) of about 10 T, due to an intrinsic upper critical field (Hc2) limitation of 14 T. To surpass this restriction, prototype Nb3Sn magnets are being developed which have reached 16 T. We show that Nb3Sn dipole technology is practically limited to 17 to 18 T due to insufficient high field pinning, and intrinsically to 20 to 22 T due to Hc2 limitations. Therefore, to obtain magnetic fields approaching 20 T and higher, a material is req...

  1. Use of movable high-field-strength intraoperative magnetic resonance imaging with awake craniotomies for resection of gliomas: preliminary experience.

    LENUS (Irish Health Repository)

    Leuthardt, Eric C

    2011-07-01

    Awake craniotomy with electrocortical mapping and intraoperative magnetic resonance imaging (iMRI) are established techniques for maximizing tumor resection and preserving function, but there has been little experience combining these methodologies.

  2. A portable high-field pulsed-magnet system for single-crystal x-ray scattering studies

    Science.gov (United States)

    Islam, Zahirul; Ruff, Jacob P. C.; Nojiri, Hiroyuki; Matsuda, Yasuhiro H.; Ross, Kathryn A.; Gaulin, Bruce D.; Qu, Zhe; Lang, Jonathan C.

    2009-11-01

    We present a portable pulsed-magnet system for x-ray studies of materials in high magnetic fields (up to 30 T). The apparatus consists of a split-pair of minicoils cooled on a closed-cycle cryostat, which is used for x-ray diffraction studies with applied field normal to the scattering plane. A second independent closed-cycle cryostat is used for cooling the sample to near liquid helium temperatures. Pulsed magnetic fields (˜1 ms in total duration) are generated by discharging a configurable capacitor bank into the magnet coils. Time-resolved scattering data are collected using a combination of a fast single-photon counting detector, a multichannel scaler, and a high-resolution digital storage oscilloscope. The capabilities of this instrument are used to study a geometrically frustrated system revealing strong magnetostrictive effects in the spin-liquid state.

  3. A portable high-field pulsed-magnet system for single-crystal x-ray scattering studies

    Energy Technology Data Exchange (ETDEWEB)

    Islam, Zahirul; Lang, Jonathan C. [X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439 (United States); Ruff, Jacob P. C.; Ross, Kathryn A.; Gaulin, Bruce D. [Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Nojiri, Hiroyuki; Matsuda, Yasuhiro H. [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Qu Zhe [Department of Physics, Tulane University, New Orleans, Louisiana 70118 (United States)

    2009-11-15

    We present a portable pulsed-magnet system for x-ray studies of materials in high magnetic fields (up to 30 T). The apparatus consists of a split-pair of minicoils cooled on a closed-cycle cryostat, which is used for x-ray diffraction studies with applied field normal to the scattering plane. A second independent closed-cycle cryostat is used for cooling the sample to near liquid helium temperatures. Pulsed magnetic fields ({approx}1 ms in total duration) are generated by discharging a configurable capacitor bank into the magnet coils. Time-resolved scattering data are collected using a combination of a fast single-photon counting detector, a multichannel scaler, and a high-resolution digital storage oscilloscope. The capabilities of this instrument are used to study a geometrically frustrated system revealing strong magnetostrictive effects in the spin-liquid state.

  4. A portable high-field pulsed-magnet system for single-crystal x-ray scattering studies

    International Nuclear Information System (INIS)

    We present a portable pulsed-magnet system for x-ray studies of materials in high magnetic fields (up to 30 T). The apparatus consists of a split-pair of minicoils cooled on a closed-cycle cryostat, which is used for x-ray diffraction studies with applied field normal to the scattering plane. A second independent closed-cycle cryostat is used for cooling the sample to near liquid helium temperatures. Pulsed magnetic fields (∼1 ms in total duration) are generated by discharging a configurable capacitor bank into the magnet coils. Time-resolved scattering data are collected using a combination of a fast single-photon counting detector, a multichannel scaler, and a high-resolution digital storage oscilloscope. The capabilities of this instrument are used to study a geometrically frustrated system revealing strong magnetostrictive effects in the spin-liquid state.

  5. First Observation of the High Field Side Sawtooth Crash and Heat Transfer during Driven Reconnection Processes in Magnetically Confined Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Park, HK; Luhmann, NC; Donne, AJH; Classen, IGJ; Domier, CW; Mazzucato, E; Munsat, T; van de Pol, MJ; Xia, Z

    2005-12-01

    High resolution (temporal and spatial), two-dimensional images of electron temperature fluctuations during sawtooth oscillations were employed to study driven reconnection processes in magnetically confined toroidal plasmas. The combination of kink and local pressure driven instabilities leads to an "X-point" reconnection process that is localized in the toroidal and poloidal planes. The reconnection is not always confined to the magnetic surfaces with minimum energy. The heat transport process from the core is demonstrated to be highly collective rather than stochastic.

  6. Orthodontic brackets in high field MR imaging: experimental evaluation of magnetic field interactions at 3.0 tesla

    International Nuclear Information System (INIS)

    Purpose: To evaluate static magnetic field interactions for 32 commonly used orthodontic brackets in a 3.0 T magnetic resonance imaging (MRI) system. Materials and methods: 32 orthodontic brackets consisting of a steel alloy (n=27), a cobalt-chromium alloy (n=2), ceramic (n=1), ceramic with a steel slot (n=1), and titanium (n=1) from 13 different manufacturers were tested for magnetic field interactions in a static magnetic field at 3.0 T (Gyroscan Intera 3.0 T, Philips Medical Systems, Best, Netherlands). The magnetic deflection force FZ [mN] was evaluated by determining the deflection angle β[ ] using the established deflection angle test according to the ASTM guidelines. The magnetic-field-induced rotational force Frot or torque was qualitatively determined using a 5-point grading scale (0: no torque; +4: very strong torque). Results: In 18 of the 32 brackets, the deflection angle β was found to be > 45 and the translational force exceeded the gravitational force FG on the particular bracket (FZ: 1.2-45.7 mN). The translational force FZ was found to be up to 68.5 times greater than the gravitational force FG (FZ/FG: 1.4-68.5). The rotational force Frot was correspondingly high (+3/+4) for those brackets. For the remaining 14 objects, the deflection angles were < 45 and the torque measurements ranged from 0 to +2. The static magnetic field did not affect the titanium bracket and the ceramic bracket. No measurable translational and rotational forces were found. (orig.)

  7. Survey of risks related to static magnetic fields in ultra high field MRI; Bestandsaufnahme zu Risiken durch statische Magnetfelder im Zusammenhang mit der Ultrahochfeld-MRT

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, H.E. [Max-Planck-Inst. fuer Kognitions- und Neurowissenschaften, Leipzig (Germany); Cramon, D.Y. von [Max-Planck-Inst. fuer Kognitions- und Neurowissenschaften, Leipzig (Germany); Max-Planck-Inst. fuer Neurologische Forschung, Koeln (Germany)

    2008-04-15

    In magnetic resonance imaging (MRI), substantial improvements with respect to sensitivity are expected due to the development of so-called ultra high field scanners, i.e., whole-body scanners with a magnetic field strength of 7 T or above. Users of this technology need to evaluate this benefit for potential risks since commercially available systems are not certified as a medical device for human use. This review provides a detailed survey of static field bioeffects related to the exposure of subjects being scanned, to occupational exposure, and to exposure of the general public under consideration of current standards and directives. According to present knowledge, it is not expected that exposure of human subjects to static magnetic fields of 7 T implies a specific risk of damage or disease provided that known contraindications are observed. The available database does not permit definition of exact thresholds for harmful effects. However, experience from previous application of ultra high field MRI indicates that transient phenomena, such as vertigo, nausea, metallic taste, or magnetophosphenes, are more frequently observed. In particular, movements in the field or the gradient of the fringe field seem to lead to detectable effects. Besides such observations, there is a strong demand for systematic investigation of potential interaction mechanisms related to static field exposure during MRI examinations. (orig.)

  8. [Comparative assessment of MR-semiotics of acutest intracerebral hematomas in low- and extra high-field frequency magnetic resonance tomography].

    Science.gov (United States)

    Skvortsova, V I; Burenchev, D V; Tvorogova, T V; Guseva, O I; Prokhorov, A V; Smirnov, A M; Kupriianov, D A; Pirogov, Iu A

    2009-01-01

    An objective of the study was to compare sensitivity of low- and extra high-field frequency magnetic resonance (MR) tomography of acutest intracerebral hematomas (ICH) and to assess differences between symptoms in obtained images. A study was conducted using experimental ICH in rats (n=6). Hematomas were formed by two injections of autologic blood into the brain. MR-devices "Bio Spec 70/30" with magnetic field strength of 7 T and "Ellipse-150" with magnetic field strength of 0,15 T were used in the study. MR-tomography was carried out 3-5 h after the injections. Both MR-devices revealed the presence of pathological lesion in all animals. Extra highfield frequency MR-tomography showed the specific signs of ICH caused by the paramagnetic effect of deoxyhemoglobin in T2 and T2*-weighted images (WI) and low frequency MR-tomography - in T2*-WI only. The comparable sensitivity of low- and extra high-field frequency MR-devices in acutest ICH was established.

  9. Neutron diffraction study of anomalous high-field magnetic phases in TmNi2B2C

    DEFF Research Database (Denmark)

    Toft, K.N.; Abrahamsen, A.B.; Eskildsen, M.R.;

    2004-01-01

    .90Yb0.10)Ni2B2C the Q(F)-->Q(AI) phase transition is also observed but at a larger transition field compared to the undoped compound. In (Tm0.85Yb0.15)Ni2B2C the Q(F) phase persists up to at least 1.8 T. The magnetic correlation length of the Q(AI) phase in TmNi2B2C measured parallel and perpendicular......We present a (B,T)-phase diagram of the magnetic superconductor TmNi2B2C obtained by neutron scattering. The measurements were performed in magnetic fields up to 6 T applied along the crystalline a axis. The observed phases are characterized by three ordering vectors, Q(F)=(0.094,0.094,0),Q(AI)=(0.......483,0,0), and Q(AII)=(0.496,0,0), all with the magnetic moment along the c axis. In zero and low fields the Tm 4f-moments order in a long wavelength transverse spin density wave with Q=Q(F). The magnetic Q(AI) structure is stabilized by an applied field of 1 T and a transition to Q(AII) is observed at 4 T...

  10. LBNL high field core program

    CERN Document Server

    Caspi, S

    2011-01-01

    The LBNL Superconducting Magnet Group mission is to develop and establish the technologies associated with high field superconducting magnets in order to provide cost-effective options for the next-generation high-energy physics accelerators. The research effort is part of the group core program and the development is part of the LARP program discussed elsewhere at this workshop.

  11. The design of the inelastic neutron scattering mode for the Extreme Environment Diffractometer with the 26 T High Field Magnet

    Energy Technology Data Exchange (ETDEWEB)

    Bartkowiak, Maciej, E-mail: maciej.bartkowiak@helmholtz-berlin.de; Stüßer, Norbert; Prokhnenko, Oleksandr

    2015-10-11

    The Extreme Environment Diffractometer is a neutron time-of-flight instrument, designed to work with a constant-field hybrid magnet capable of reaching fields over 26 T, unprecedented in neutron science; however, the presence of the magnet imposes both spatial and technical limitations on the surrounding instrument components. In addition to the existing diffraction and small-angle neutron scattering modes, the instrument will operate also in an inelastic scattering mode, as a direct time-of-flight spectrometer. In this paper we present the Monte Carlo ray-tracing simulations, the results of which illustrate the performance of the instrument in the inelastic-scattering mode. We describe the focussing neutron guide and the chopper system of the existing instrument and the planned design for the instrument upgrade. The neutron flux, neutron spatial distribution, divergence distribution and energy resolution are calculated for standard instrument configurations.

  12. Magnetofluorescent micelles incorporating Dy(III)-DOTA as potential bimodal agents for optical and high field magnetic resonance imaging.

    Science.gov (United States)

    Harris, Michael; Vander Elst, Luce; Laurent, Sophie; Parac-Vogt, Tatjana N

    2016-03-21

    Dysprosium(iii) was coordinated to four 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) bisamide derivatives functionalized with amphiphilic p-dodecylaniline and p-tetradecylaniline in a differing cis- and trans-orientation. The complexes were assembled into mono-disperse micelles having size distribution maxima ranging from 10 to 15 nm and the magnetic and optical properties of the micelles were examined in detail. The micelles show characteristic Dy(iii) emission with quantum yields reaching 0.8%. The transverse relaxivity r2 per Dy(iii) ion at 500 MHz and 310 K reaches maximum values of ca. 20 s(-1) mM(-1) which is a large increase when compared to a value of 0.8 s(-1) mM(-1) observed for Dy(III)-DTPA. The micelles were stable in water when incubated at 37 °C for 1 week and showed no relaxivity decrease when measured in the presence of 4% (w/v) human serum albumin. The efficient T2 relaxation, especially at strong magnetic fields, is sustained by the high magnetic moment of the dysprosium(iii) ion, the coordination of water molecules and long rotational correlation times. PMID:26865457

  13. Cardiothoracic ratio on chest radiograph in pediatric heart disease: How does it correlate with heart volumes at magnetic resonance imaging?

    Energy Technology Data Exchange (ETDEWEB)

    Grotenhuis, Heynric B. [The University of Toronto, Division of Cardiology, Department of Paediatrics, The Labatt Family Heart Centre, The Hospital for Sick Children, Toronto (Canada); Zhou, Cheng; Isaac, Kathryn V. [The University of Toronto, Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto (Canada); Tomlinson, George [University of Toronto, Department of Medicine, Toronto General Hospital and Mt. Sinai Hospital, Toronto (Canada); Seed, Mike; Grosse-Wortmann, Lars; Yoo, Shi-Joon [The University of Toronto, Division of Cardiology, Department of Paediatrics, The Labatt Family Heart Centre, The Hospital for Sick Children, Toronto (Canada); The University of Toronto, Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto (Canada)

    2015-10-15

    The cardiothoracic ratio by chest radiograph is widely used as a marker of cardiac size. The purpose of this study is to correlate cardiothoracic ratio and cardiac volumes as measured by cardiovascular magnetic resonance (MR) in common structural and myopathic heart disease with increased cardiac size due to volume overload or hypertrophy. A retrospective single center study was performed in all patients between 2007 and 2013 with repaired tetralogy of Fallot (TOF), aortic regurgitation, isolated left-to-right shunt and hypertrophic cardiomyopathy (HCM) who underwent cardiovascular MR and chest radiograph within 6 months of each other. Cardiothoracic ratios by chest radiograph (frontal and lateral) were compared to cardiac volumes (indexed for body surface area) by cardiovascular MR. One hundred twenty-seven patients (mean age: 11.2 ± 5.5 years) were included in this study (76 with TOF, 23 with isolated left-to-right shunt, 16 with aortic regurgitation and 12 with HCM). Frontal cardiothoracic ratio of all groups correlated with indexed right ventricular (RV) end-diastolic volume (EDVI) (r = 0.40, P < 0.01) and indexed total heart volume (THVI) (r = 0.27, P < 0.01). In TOF patients, frontal cardiothoracic ratio correlated with RVEDVI (r = 0.34, P < 0.01; coefficient of variation = 27.6%), indexed RV end-systolic volume (ESVI) (r = 0.44, P < 0.01; coefficient of variation = 33.3%) and THVI (r = 0.35, P < 0.01; coefficient of variation = 19.6%), although RV volumes and THVI showed widespread variation given the high coefficients of variation. In patients with aortic regurgitation, frontal cardiothoracic ratio correlated with left ventricular (LV) EDVI (r = 0.50, P = 0.047), but not with THVI and aortic regurgitant fraction, and widespread variation for LV EDVI (coefficient of variation = 19.2%), LV ESVI (coefficient of variation = 32.5%) and THVI (coefficient of variation = 13.6%) was also observed. Frontal cardiothoracic ratio was not correlated with cardiac volumes

  14. Cardiothoracic ratio on chest radiograph in pediatric heart disease: How does it correlate with heart volumes at magnetic resonance imaging?

    International Nuclear Information System (INIS)

    The cardiothoracic ratio by chest radiograph is widely used as a marker of cardiac size. The purpose of this study is to correlate cardiothoracic ratio and cardiac volumes as measured by cardiovascular magnetic resonance (MR) in common structural and myopathic heart disease with increased cardiac size due to volume overload or hypertrophy. A retrospective single center study was performed in all patients between 2007 and 2013 with repaired tetralogy of Fallot (TOF), aortic regurgitation, isolated left-to-right shunt and hypertrophic cardiomyopathy (HCM) who underwent cardiovascular MR and chest radiograph within 6 months of each other. Cardiothoracic ratios by chest radiograph (frontal and lateral) were compared to cardiac volumes (indexed for body surface area) by cardiovascular MR. One hundred twenty-seven patients (mean age: 11.2 ± 5.5 years) were included in this study (76 with TOF, 23 with isolated left-to-right shunt, 16 with aortic regurgitation and 12 with HCM). Frontal cardiothoracic ratio of all groups correlated with indexed right ventricular (RV) end-diastolic volume (EDVI) (r = 0.40, P < 0.01) and indexed total heart volume (THVI) (r = 0.27, P < 0.01). In TOF patients, frontal cardiothoracic ratio correlated with RVEDVI (r = 0.34, P < 0.01; coefficient of variation = 27.6%), indexed RV end-systolic volume (ESVI) (r = 0.44, P < 0.01; coefficient of variation = 33.3%) and THVI (r = 0.35, P < 0.01; coefficient of variation = 19.6%), although RV volumes and THVI showed widespread variation given the high coefficients of variation. In patients with aortic regurgitation, frontal cardiothoracic ratio correlated with left ventricular (LV) EDVI (r = 0.50, P = 0.047), but not with THVI and aortic regurgitant fraction, and widespread variation for LV EDVI (coefficient of variation = 19.2%), LV ESVI (coefficient of variation = 32.5%) and THVI (coefficient of variation = 13.6%) was also observed. Frontal cardiothoracic ratio was not correlated with cardiac volumes

  15. An ultra­high field Magnetic Resonance Spectroscopy study of post exercise brain lactate, glutamate and glutamine change in the human brain.

    Directory of Open Access Journals (Sweden)

    Andrea eDennis

    2015-12-01

    Full Text Available During strenuous exercise there is a progressive increase in lactate uptake and metabolism into the brain as workload and plasma lactate levels increase. Although it is now widely accepted that the brain can metabolise lactate, few studies have directly measured brain lactate following vigorous exercise. Here, we used ultra-high field Magnetic Resonance Spectroscopy of the brain to obtain static measures of brain lactate, as well as brain glutamate and glutamine after vigorous exercise. The aims of our experiment were to (a track the changes in brain lactate following recovery from exercise and, (b to simultaneously measure the signals from brain glutamate and glutamine. The results of our experiment showed that vigorous exercise resulted in a significant increase in brain lactate. Furthermore, both glutamate and glutamine were successfully resolved, and as expected, although contrary to some previous reports, we did not observe any significant change in either amino acid after exercise. We did however observe a negative correlation between glutamate and a measure of fitness. These results support the hypothesis that peripherally-derived lactate is taken up by the brain when available. Our data additionally highlight the potential of ultra-high field magnetic resonance spectroscopy as a non-invasive way of measuring multiple brain metabolite changes with exercise.

  16. ARC: A compact, high-field, fusion nuclear science facility and demonstration power plant with demountable magnets

    OpenAIRE

    Sorbom, B. N.; Ball, J.; Palmer, T. R.; Mangiarotti, F. J.; Sierchio, J. M.; Bonoli, P.; Kasten, C.; Sutherland, D. A.; Barnard, H. S.; Haakonsen, C. B.; Goh, J.; Sung, C; Whyte, D. G.

    2014-01-01

    The affordable, robust, compact (ARC) reactor conceptual design study aims to reduce the size, cost, and complexity of a combined fusion nuclear science facility (FNSF) and demonstration fusion Pilot power plant. ARC is a 200-250 MWe tokamak reactor with a major radius of 3.3 m, a minor radius of 1.1 m, and an on-axis magnetic field of 9.2 T. ARC has rare earth barium copper oxide (REBCO) superconducting toroidal field coils, which have joints to enable disassembly. This allows the vacuum ves...

  17. Low field-low cost: Can low-field magnetic resonance systems replace high-field magnetic resonance systems in the diagnostic assessment of multiple sclerosis patients?

    International Nuclear Information System (INIS)

    As low-field MR imaging is becoming a widely used imaging technique, we aimed at a prospective assessment of differences in imaging quality between low- and high-field MR imaging in multiple sclerosis patients possibly interfering with diagnostic or therapeutic decision making. Twenty patients with clinically proven multiple sclerosis were examined with optimized imaging protocols in a 1.5- and a 0.23-T MR scanner within 48 h. Images were assessed independently by two neuroradiologists. No statistically significant interrater discrepancies were observed. A significantly lower number of white matter lesions could be identified in low-field MR imaging both on T1- and on T2-weighted images (T2: high field 700, low field 481; T1: high field 253, low field 177). A total of 114 enhancing lesions were discerned in the high-field MR imaging as opposed to 45 enhancing lesions in low-field MR imaging. Blood-brain barrier disruption was identified in 11 of 20 patients in the high-field MR imaging, but only in 4 of 20 patients in low-field MR imaging. Since a significantly lower lesion load is identified in low-field MR imaging than in high-field MR imaging, and blood-brain barrier disruption is frequently missed, caution must be exercised in interpreting a normal low-field MR imaging scan in a patient with clinical signs of multiple sclerosis and in interpreting a scan without enhancing lesions in a patient with known multiple sclerosis and clinical signs of exacerbation. (orig.)

  18. A retunable surface coil for high field 31P and 1H magnetic resonance evaluations of the living mouse leg

    International Nuclear Information System (INIS)

    This study presents a retunable surface coil that can be adjusted to at least two Larmor frequencies sequentially without the need to remove the coil from the magnet and while avoiding interference between channels. A prototype 1H/31P surface coil for the analysis of the in vivo mouse leg under electrical stimulation was designed for operation at 11.75 T. The coil has a high-quality factor of over 100 for both operational frequencies. To demonstrate the capabilities of this simple design, in vivo experiments were conducted to acquire high-resolution 1H images and 31P spectra of the C57BL/6 mouse leg, both with high temporal resolution. Proton diffusion tensor imaging was also performed to evaluate rodent skeletal muscle architecture. This design makes the acquisition of physiological data about both muscle structure and energetics (PCr, ATP and Pi) possible in a single experimental session

  19. ARC: A compact, high-field, fusion nuclear science facility and demonstration power plant with demountable magnets

    CERN Document Server

    Sorbom, B N; Palmer, T R; Mangiarotti, F J; Sierchio, J M; Bonoli, P; Kasten, C; Sutherland, D A; Barnard, H S; Haakonsen, C B; Goh, J; Sung, C; Whyte, D G

    2014-01-01

    The affordable, robust, compact (ARC) reactor conceptual design study aims to reduce the size, cost, and complexity of a combined fusion nuclear science facility (FNSF) and demonstration fusion Pilot power plant. ARC is a 270 MWe tokamak reactor with a major radius of 3.3 m, a minor radius of 1.1 m, and an on-axis magnetic field of 9.2 T. ARC has rare earth barium copper oxide (REBCO) superconducting toroidal field coils, which have joints to enable disassembly. This allows the vacuum vessel to be replaced quickly, mitigating first wall survivability concerns, and permits a single device to test many vacuum vessel designs and divertor materials. The design point has a plasma fusion gain of Q_p~13.6, yet is fully non-inductive, with a modest bootstrap fraction of only ~63%. Thus ARC offers a high power gain with relatively large external control of the current profile. This highly attractive combination is enabled by the ~23 T peak field on coil with newly available REBCO superconductor technology. External cu...

  20. An Ultra-High Field Magnetic Resonance Spectroscopy Study of Post Exercise Lactate, Glutamate and Glutamine Change in the Human Brain.

    Science.gov (United States)

    Dennis, Andrea; Thomas, Adam G; Rawlings, Nancy B; Near, Jamie; Nichols, Thomas E; Clare, Stuart; Johansen-Berg, Heidi; Stagg, Charlotte J

    2015-01-01

    During strenuous exercise there is a progressive increase in lactate uptake and metabolism into the brain as workload and plasma lactate levels increase. Although it is now widely accepted that the brain can metabolize lactate, few studies have directly measured brain lactate following vigorous exercise. Here, we used ultra-high field magnetic resonance spectroscopy of the brain to obtain static measures of brain lactate, as well as brain glutamate and glutamine after vigorous exercise. The aims of our experiment were to (a) track the changes in brain lactate following recovery from exercise, and (b) to simultaneously measure the signals from brain glutamate and glutamine. The results of our experiment showed that vigorous exercise resulted in a significant increase in brain lactate. Furthermore, both glutamate and glutamine were successfully resolved, and as expected, although contrary to some previous reports, we did not observe any significant change in either amino acid after exercise. We did however observe a negative correlation between glutamate and a measure of fitness. These results support the hypothesis that peripherally derived lactate is taken up by the brain when available. Our data additionally highlight the potential of ultra-high field MRS as a non-invasive way of measuring multiple brain metabolite changes with exercise. PMID:26732236

  1. High-field open versus short-bore magnetic resonance imaging of the spine: a randomized controlled comparison of image quality.

    Directory of Open Access Journals (Sweden)

    Judith Enders

    Full Text Available BACKGROUND: The purpose of the present study was to compare the image quality of spinal magnetic resonance (MR imaging performed on a high-field horizontal open versus a short-bore MR scanner in a randomized controlled study setup. METHODS: Altogether, 93 (80% women, mean age 53 consecutive patients underwent spine imaging after random assignement to a 1-T horizontal open MR scanner with a vertical magnetic field or a 1.5-T short-bore MR scanner. This patient subset was part of a larger cohort. Image quality was assessed by determining qualitative parameters, signal-to-noise (SNR and contrast-to-noise ratios (CNR, and quantitative contour sharpness. RESULTS: The image quality parameters were higher for short-bore MR imaging. Regarding all sequences, the relative differences were 39% for the mean overall qualitative image quality, 53% for the mean SNR values, and 34-37% for the quantitative contour sharpness (P<0.0001. The CNR values were also higher for images obtained with the short-bore MR scanner. No sequence was of very poor (nondiagnostic image quality. Scanning times were significantly longer for examinations performed on the open MR scanner (mean: 32±22 min versus 20±9 min; P<0.0001. CONCLUSIONS: In this randomized controlled comparison of spinal MR imaging with an open versus a short-bore scanner, short-bore MR imaging revealed considerably higher image quality with shorter scanning times. TRIAL REGISTRATION: ClinicalTrials.gov NCT00715806.

  2. Development and testing of high field, high current density solenoids and magnets, wound with stabilized filamentary Nb/sub 3/Sn cable and reacted after winding

    CERN Document Server

    Asner, Alfred M; Hagedorn, Dietrich; Niqueletto, Christian; Thomi, W

    1981-01-01

    The development and testing of a 2.6 cm inner diameter, high field and high current density solenoid, wound with a Cu-stabilized, fine filamentary Nb/sub 3/Sn cable, and reacted after winding, is described. At an overall current density in the winding of 352 A/mm /sup 2/, corresponding to the current density of 565 A/mm/sup 2/ in the non-insulated cable, a maximum field of B/sub m/=8.8 T had been obtained without any training. Based on this result, a 0.9 m-long, 10 cm-warm bore, beam line quadrupole magnet, wound with the same cable, is being assembled. The nominal parameters are: field gradient 74 T/m, maximum field in the winding B/sub m/=7.4 T at an overall current density in the winding of 300 A/mm/sup 2/. The specific technological and design aspects of this magnet, related to the 'wind and react' technique, such as the conductor insulation, coil winding technique, execution of connections etc., are discussed. (2 refs).

  3. Chest drainage.

    Science.gov (United States)

    Carter, Chris

    2014-07-15

    As an intensive care nurse with experience of caring for critically ill patients in the UK and on deployed operations overseas, I found the CPD article useful in reviewing the pathophysiology of a pneumothorax, use of intrapleural chest drains, observations that should be recorded, and nursing care and management of a patient with an intrapleural chest drain. Reflecting on the time out activities in the CPD article was valuable. PMID:25005418

  4. The Travelling-Wave Primate System: A New Solution for Magnetic Resonance Imaging of Macaque Monkeys at 7 Tesla Ultra-High Field.

    Directory of Open Access Journals (Sweden)

    Tim Herrmann

    Full Text Available Neuroimaging of macaques at ultra-high field (UHF is usually conducted by combining a volume coil for transmit (Tx and a phased array coil for receive (Rx tightly enclosing the monkey's head. Good results have been achieved using vertical or horizontal magnets with implanted or near-surface coils. An alternative and less costly approach, the travelling-wave (TW excitation concept, may offer more flexible experimental setups on human whole-body UHF magnetic resonance imaging (MRI systems, which are now more widely available. Goal of the study was developing and validating the TW concept for in vivo primate MRI.The TW Primate System (TWPS uses the radio frequency shield of the gradient system of a human whole-body 7 T MRI system as a waveguide to propagate a circularly polarized B1 field represented by the TE11 mode. This mode is excited by a specifically designed 2-port patch antenna. For receive, a customized neuroimaging monkey head receive-only coil was designed. Field simulation was used for development and evaluation. Signal-to-noise ratio (SNR was compared with data acquired with a conventional monkey volume head coil consisting of a homogeneous transmit coil and a 12-element receive coil.The TWPS offered good image homogeneity in the volume-of-interest Turbo spin echo images exhibited a high contrast, allowing a clear depiction of the cerebral anatomy. As a prerequisite for functional MRI, whole brain ultrafast echo planar images were successfully acquired.The TWPS presents a promising new approach to fMRI of macaques for research groups with access to a horizontal UHF MRI system.

  5. Chemical spray pyrolysis of Tl-Ba-Ca-Cu-O high-T(sub c) superconductors for high-field bitter magnets

    Science.gov (United States)

    Derochemont, L. Pierre; Zhang, John G.; Squillante, Michael R.; Hermann, A. M.; Duan, H. M.; Andrews, Robert J.; Kelliher, Warren C.

    1991-01-01

    The deposition of Tl-Ba-Ca-Cu-O thick films by spray pyrolyzing a Ba-Ca-Cu-O precursor film and diffusing thallium into the film to form the superconducting phase is examined. This approach was taken to reduce exposure to thallium and its health and safety hazards. The Tl-Ba-Ca-Cu-O system was selected because it has very attractive features which make it appealing to device and manufacturing engineering. Tl-Ba-Ca-Cu-O will accommodate a number of superconducting phases. This attribute makes it very forgiving to stoichiometric fluctuations in the bulk and film. It has excellent thermal and chemical stability, and appears to be relatively insensitive to chemical impurities. Oxygen is tightly bound into the systems, consequently there is no orthorhombic (conductor) to tetragonal (insulator) transition which would affect a component's lifetime. More significantly, the thallium based superconductors appear to have harder magnetic properties than the other high-Tc oxide ceramics. Estimates using magnetoresistance measurements indicate that at 77 K Tl2Ba2CaCu2O10 will have an upper critical field, H(sub c2) fo 26 Tesla for applied fields parallel to the c-axis and approximately 1000 Tesla for fields oriented in the a-b plane. Results to date have shown that superconducting films can be reproducibly deposited on 100 oriented MgO substrates. One film had a zero resistance temperature of 111.5 K. Furthermore, x ray diffraction analysis of the films showed preferential c-axis orientation parallel to the plane of the substrate. These results have now made it possible to consider the manufacture of a superconducting tape wire which can be configured into a topology useful for high-field magnet designs. The research which leads to the preparation of these films and plans for further development are reviewed.

  6. Processing and characterization of superconducting solenoids made of Bi-2212/Ag-alloy multifilament round wire for high field magnet applications

    Science.gov (United States)

    Chen, Peng

    As the only high temperature superconductor with round wire (RW) geometry, Bi2Sr2CaCu2O8+x (Bi-2212) superconducting wire has the advantages of being multi-filamentary, macroscopically isotropic and twistable. With overpressure (OP) processing techniques recently developed by our group at the National High Magnetic Field Laboratory (NHMFL), the engineering current density (Je) of Bi-2212 RW can be dramatically increased. For example, Je of more than 600 A/mm 2 (4.2 K and 20 T) is achieved after 100 bar OP processing. With these intrinsically beneficial properties and recent processing progress, Bi-2212 RW has become very attractive for high field magnet applications, especially for nuclear magnetic resonance (NMR) magnets and accelerator magnets etc. This thesis summarizes my graduate study on Bi-2212 solenoids for high field and high homogeneity NMR magnet applications, which mainly includes performance study of Bi-2212 RW insulations, 1 bar and OP processing study of Bi-2212 solenoids, and development of superconducting joints between Bi-2212 RW conductors. Electrical insulation is one of the key components of Bi-2212 coils to provide sufficient electrical standoff within coil winding pack. A TiO 2/polymer insulation offered by nGimat LLC was systematically investigated by differential thermal analysis (DTA), thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), dielectric property measurements, and transport critical current (Ic) property measurements. About 29% of the insulation by weight is polymer. When the Bi-2212 wire is fully heat treated, this decomposes with slow heating to 400 °C in flowing O2. After the full reaction, we found that the TiO2 did not degrade the critical current properties, adhered well to the conductor, and provided a breakdown voltage of more than 100 V. A Bi-2212 RW wound solenoid coil was built using this insulation being offered by nGimat LLC. The coil resistance was constant through coil winding, polymer burn

  7. Magnetic resonance imaging of hindfoot involvement in patients with spondyloarthritides: Comparison of low-field and high-field strength units

    Energy Technology Data Exchange (ETDEWEB)

    Eshed, Iris; Althoff, Christian E. [Department of Radiology, Charite Medical School, Berlin (Germany); Feist, Eugen [Department of Rheumatology and Clinical Immunology, Charite Medical School, Berlin (Germany); Minden, Kirsten [Helios Clinics, 2nd Children' s Hospital Berlin-Buch, Rheumatology Unit, Berlin (Germany); German Rheumatology Research Center, Berlin (Germany); Schink, Tania [Department of Medical Biometry, Charite Medical School, Berlin (Germany); Hamm, Bernd [Department of Radiology, Charite Medical School, Berlin (Germany); Hermann, Kay-Geert A. [Department of Radiology, Charite Medical School, Berlin (Germany)], E-mail: kgh@charite.de

    2008-01-15

    Objective: To compare MRI evaluation of a painful hindfoot of patients with spondyloarthritides (SpA) on low-field (0.2 T) versus high-field (1.5 T) MRI. Materials and methods: Patients with SpA and hindfoot pain were randomly referred to either high-field or low-field MRI. Twenty-seven patients were evaluated (male/female: 17:10; mean age: 39 {+-} 1.4 years). Fifteen patients were examined by low-field and 12 by high-field MRI. Two patients (evaluated by high-field MRI) were excluded. Images were separately read by two radiologists who later reached a consensus. In each patient the prevalence of erosions, fluid, synovitis or bone marrow edema of the hindfoot joints, tendinosis or tenosynovitis of tendons, enthesitis of the plantar fascia and Achilles tendon and retrocalcaneal bursitis were recorded. Clinical and demographic parameters were comparable between both groups. Results: MRI evaluation of joints and tendons of the hindfoot revealed no significant differences in patients with SpA groups for all parameters. Analyzing all joints or tendons together, there was no statistically significant difference between the two groups. Conclusion: Low-field and high-field MRI provide comparable information for evaluation of inflammatory hindfoot involvement. Thus, low-field MRI can be considered as a reliable diagnostic tool for the detection of hindfoot abnormalities in SpA patients.

  8. Investigation of the metabolic changes in visual cortex due to visual stimulation using high field magnetic resonance spectroscopy at 7.0 T

    International Nuclear Information System (INIS)

    Objective: To investigate the metabolic changes in the visual cortex due to visual stimulation using high field functional proton magnetic resonance spectroscopy at 7.0 T. A clear picture of brain metabolism and neurotransmitter activity during activation was expected to be established. Methods: Nine healthy subjects participated in this study. All MR measurements were acquired using a 7.0 T MR system and a 16-channel SENSE head coil. An initial fMRI scan was performed prior to spectroscopic acquisition in order to determine the activated region in the visual cortex. A cubic ROI of 2 cm× 2 cm × 2 cm was positioned inside the activated region for functional MRS acquisition. A short TE STEAM sequence was used for acquiring the MRS data. The functional paradigm comprised 6.6 min baseline followed by 13.2 min of visual stimulation and 19.8 min recovery. Summed averaged spectra for visual stimulus off and visual stimulus on were analyzed separately using LC Model and internal reference of water. A Wilcoxon signed rank test was conducted to compare the metabolite changes. Results During stimulation, concentration in Asp [(3.20 ± 0.28) μmol/g], Gln [(2.07 ± 0.10) μmol/g] and Gly [(1.65 ± 0.11)μmol/g] was found to be significantly decreased,compared with that of (3.52 ± 0.28), (2.25 ± 0.10) and (1.85 ± 0.11) μmol/g in rest (Z=-2.073, -2.073 and -2.429, respectively, P<0.05). The level in Glu [(11.50 ± 0.11) μmol/g], GSH [(2.45 ± 0.10) μmol/g] and Lac [(0.89 ± 0.05) μmol/g] due to neuronal activation was found to be significantly increased,versus resting concentration of (11.28 ± 0.11), (2.28 ± 0.10) and (0.79 ± 0.05) μmol/g,respectively (Z=2.521, 2.310, 2.016, respectively, P<0.05). Glc level [(1.54 ± 0.23)μmol/g] exhibited a tendency to decrease throughout the period of stimulation, compared with that of [(1.78 ± 0.28) μmol/g] in rest,but the decrease did not reach statistical significance (Z=-1.897, P>0.05). Conclusions: Using a novel visual

  9. Some applications of a new, simple, very high-field (0-12 tesla) super-conducting magnet-cryostat based on a niobium-titanium mini-solenoid

    International Nuclear Information System (INIS)

    High magnetic fields have been and continue to be important in Moessbauer spectroscopy, especially in the study of the H vs. T characteristics of magnetically ordered materials. In this work we describe a new, particularly simple high-field magnet cryostat system for which the rated field at T=4.2 K is 9.0 T at 37.58 amps operating current and which is found capable of significant enhancement to 11.7 T on pumping the magnet bath to ≅ 1.7 K. The field enhancement (≅ 30%) is to our knowledge the largest achieved to date for such a niobium-titanium solenoid, the previous high for NbTi being ≅ 20%. Somewhat smaller enhancement (≅ 9.5%) is found on similar pumping of Nb3Sn solenoids, i.e., 137 kG at 4.2 K to 150 kG at 1.9 K. Among the unique features of the present system are its small volume (leading to minimal stored energy and liquid helium loss during quench excursions) and its high field: current ratio ≅ 2.4 kG/amp versus < 1 kG/amp values of typical larger NbTi solenoids currently in use. This leads to lower helium consumption during charging cycles to persistent mode operation and is especially important to field enhancement via continued pumping along the vapor cooled leads in addition to directly on the magnet bath. (orig./BHO)

  10. Effect of composition on Curie temperature, magnetic moment, and high-field susceptibility of amorphous Fe90-xMxZr10 (M=V, Cr, Mn, Co, Ni, Cu, Si, and B) alloys

    International Nuclear Information System (INIS)

    Magnetization measurements for amorphous Fe90-xMxZr10 (M=V, Cr, Mn, Co, Ni, Cu, Si, and B) alloys prepared by single-roller spin quenching have been made by an extracting sample magnetometer in magnetic fields up to 65 kOe and at temperatures ranging from 1.5 to 300 K. Preliminary results show that the magnetic properties of these amorphous alloys strongly depend upon the M concentration and display a similarity to those of the parent Fe-Zr base; compared with amorphous Fe-M-B alloys with the same concentration, all the samples are characterized by a large high-field susceptibility, a small magnetic moment, and a low Curie temperature, which, for low M concentration, are particularly sensitive to applied fields. The noncollinear spin structures that characterize Fe-rich Fe-Zr--based amorphous alloys have been proposed to explain the observed results

  11. High field superconducting magnet: Science, Technology and Applications%高场超导磁体科学技术与应用

    Institute of Scientific and Technical Information of China (English)

    王秋良

    2013-01-01

    科学技术的发展对于磁场强度质量的要求越来越高,极端强磁场条件是人类追求的永远的科学目标,它孕育着许多重大的科学发现和新技术的产生,对人类的科学和技术以及生活产生重大的影响.以磁体为核心与电力电子器件以及相关的软件等结合可以构成各种各样科学仪器和装置,广泛应用在科学研究和工业特种装备中.磁技术对于人类的科学与技术进步起到越来越重要的作用,尤其是极高磁场所带来的诸多优点,使得人类对于物质世界认识不断加深,对于生命的起源以及从事疾病的防治的研究有特别重要的意义.本文介绍磁体基本原理、磁场产生的方法与应用以及相关的发展.%Development of superconducting magnet science and technology requires a magnetic field with high strength and good quality.The pursuit of extremely high magnetic field is an eternal scientific goal forscientists and engineers.It is an exciting cutting-edge technology with full of challenges and has been essential for many significant discoveries in science and technology.Combined with power-electronic devices and related software,a whole magnet system can be built up as the key component of various types of scientific instruments and other equipment,and can be fund widespread applications in scientific research and industry.Magnet technology is currently playing a more and more important role in scientific and technological progress.Ultra-high magnetic fields help to give us much deeper understanding of the world of matter and have special significance for research into the origins of life and disease prevention.In this review article,basic magnet principles,methods of generating magnetic fields,magnetic field applications,and numerical methods for the design of magnet structures are briefly introduced and reviewed.

  12. The chest

    International Nuclear Information System (INIS)

    Radiographic interpretation of chest films of newborns in respiratory distress remains one of the most difficult aspects of pediatric radiology. Complex pulmonary and cardiac adjustments to extrauterine life are rapidly taking place. The small, fluid-filled fetal lung must rid itself of fluid and fill with air. The high vascular resistance of the fetal pulmonary bed and the open ductus arteriosus allow shunting of blood in both directions. Films taken in this period of time may show lungs that resemble those seen in congestive heart failure or fluid overload. When these findings are observed in infants who may appear dusky or even cyanotic, the result may be the diagnosis of disease in normal infants passing through a stormy transition period. To make things worse, the films are taken as portable surpine films, usually in an isolette in the intensive care unit (ICU). The phase of respiration is difficult, if not impossible, to control, and lateral films are usually not obtained. Many of the infants are on assisted ventilation either by tube or nasal prongs-nasal continuous positive airway pressure (CPAP)-and lungs can appear over-inflated or whited out, depending on the pressures used and the phase of the respiratory cycle. Prolonged crying itself can make lungs appear semiopaque; the next breath may show such a dramatic reinflation that it is hard to believe the two films are of the same infant, made only seconds apart. Is the heart large? Or is it the thymus? Are the lungs ''wet''? Is there infection? Is there pulmonary vascular engorgement? Why are these films so hard to interpret? They have no easy answers. The radiologist must realize that the neonatal intensive care personnel, armed though they may be with blood gas values, are no better at interpreting films. If anything, they read into them what they wish to see

  13. Chest X-Ray

    Medline Plus

    Full Text Available ... by: Image/Video Gallery Your radiologist explains chest x-ray. Transcript Welcome to Radiology Info dot org! Hello, ... you about chest radiography also known as chest x-rays. Chest x-rays are the most commonly performed ...

  14. Development of a 40 mm bore magnet cross section with high field uniformity for the 6.6T SSC dipole

    International Nuclear Information System (INIS)

    The SSC requires a very uniform dipole field. A 40 mm bore diameter winding cross section has been developed which has computed multipole coefficients less than 1 x 10-6 of the dipole field at 10 mm radius for an operating field of 6.6T at 4.35 K. This cross section has 4 conductor blocks (3 wedges, 16 turns) per quadrant in the inner layer, and two blocks (1 wedge, 20 turns) in the outer layer. ''Partially keystoned'' cable is used; the inner cable has 23 strands of .0318 inch diameter wire; the outer cable has 30 strands of .0255 inch diameter wire. Model magnets have been constructed and the fields measured at room temperature and at liquid helium temperature up to fields exceeding 6.6T. Measured fields are compared to the predicted field. In addition, the as-built conductor positions in several magnets have been determined after cutting up the magnets. The predictions based on as-built configurations are computed and compared to measurements

  15. Specific proof of various stages of Osler's disease of the brain via high field magnetic resonance tomography (1. 5 Tesla)

    Energy Technology Data Exchange (ETDEWEB)

    Billet, F.; Bluemm, R.G.; Beyer, H.K.

    1988-08-01

    MR is a sensitive noninvasive examination method for diagnosing parenchymatous cryptic arteriovenous malformations and sequels of cerebral haemorrhage. In a patient with recurring nosebleed and brain stem syndrome eleven so-called cryptic arteriovenous malformations or their haemorrhage sequels were diagnosed via magnetic resonance tomography. Basing on these specific findings, nosebleeding, and a positive family anamnesis, the findings could be classified as belonging to manifestations of Osler's disease (hereditary haemorrhagic telangiectasia). This rare disease is characterised by a triad of signs: telangiectasias, recurring bleeding, and heredity. In this article the specific MR image is compared with the CT pattern and the results are discussed against the background of literature on Osler's disease which is also known as Rendu-Osler-Weber disease.

  16. Future directions in fusion research: Super high field tokamaks

    International Nuclear Information System (INIS)

    Recent experimental results and advances in magnet engineering suggest that super high field, high aspect ratio tokamak devices could be a very efficient way to achieve burning plasma conditions and could open up a new area of research. Copper magnet devices with fields of 13 to 25 T at the plasma are considered. The super high field approach could also provide advantages for ETR and demonstration/commercial reactor concepts (magnetic fields at the plasma in the 8 to 13 T range)

  17. Magnetic resonance-guided upper abdominal biopsies in a high-field wide-bore 3-T MRI system: feasibility, handling, and needle artefacts

    Energy Technology Data Exchange (ETDEWEB)

    Kuehn, Jens-Peter; Langner, Soenke; Hegenscheid, Katrin; Hosten, Norbert; Puls, Ralf [Ernst Moritz Arndt University of Greifswald, Department of Radiology, Greifswald (Germany); Evert, Matthias [Ernst Moritz Arndt University of Greifswald, Department of Pathology, Greifswald (Germany); Kickhefel, Antje [Siemens Healthcare, Erlangen (Germany)

    2010-10-15

    To investigate the feasibility and handling of abdominal MRI-guided biopsies in a 3-T MRI system. Over a 1-year period, 50 biopsies were obtained in 47 patients with tumours of the upper abdominal organs guided by 3-T MRI with a large-bore diameter of 70 cm. Lesions in liver (47), spleen (1) and kidney (2) were biopsied with a coaxial technique using a 16-G biopsy needle guided by a T1-weighted three-dimensional gradient recalled echo volumetric interpolated breath-hold examination (T1w-3D-GRE-VIBE) sequence. Sensitivity, specificity, accuracy, complication rate, interventional complexity, room/intervention time and needle artefacts were determined. A sensitivity of 0.93, specificity of 1.0 and accuracy of 0.94 were observed. Three patients required a rebiopsy. There was a minor complications rate of 13.6%, and no major complications were observed. Histopathology revealed 38 malignant lesions, and 3-month follow-up confirmed 9 benign lesions. Mean lesion diameter was 3.4 {+-} 3.1 cm (50% being smaller than 2 cm). Mean needle tract length was 10.8 {+-} 3.3 cm. Median room time was 42.0 {+-} 19.8 min and intervention time 9.3 {+-} 8.1 min. Needle artefact size was about 9-fold greater for perpendicular access versus access parallel to the main magnetic field. Biopsies of the upper abdomen can be performed with great technical success and easy handling because of the large-bore diameter. The MRI-guided biopsy needle had an acceptable susceptibility artefact at 3 T. However future research must aim to reduce the susceptibility effects of the biopsy systems. (orig.)

  18. Chest X-Ray

    Medline Plus

    Full Text Available ... chest x-ray is used to evaluate the lungs, heart and chest wall and may be used ... diagnose and monitor treatment for a variety of lung conditions such as pneumonia, emphysema and cancer. A ...

  19. High-field magnetization of a two-dimensional spin frustration system, Ni{sub 5}(TeO{sub 3}){sub 4}X{sub 2} (X = Br, Cl)

    Energy Technology Data Exchange (ETDEWEB)

    Her, J L; Matsuda, Y H; Suga, K; Kindo, K; Takeyama, S [Institute for Solid State Physics, University of Tokyo (Japan); Berger, H [Institutes of Physics of Complex Matter, EPFL, Lausanne (Switzerland); Yang, H D [Department of Physics, Center for Nanoscience and Nanotechnology, National Sun Yat-sen University, Taiwan (China)

    2009-10-28

    The high-field magnetization, M(H), of Ni{sub 5}(TeO{sub 3}){sub 4}X{sub 2} (X = Br, Cl) was measured by using a pulse magnet. These compounds have a two-dimensional crystal structure and a distorted Kagome spin frustrated system which is built from the Ni{sup 2+} ions (S = 1). The Neel transition temperatures are T{sub N}approx28 and 23 K for X = Br and Cl, respectively. When TT{sub N}, the field-dependent magnetization curves behave like a monotonically increasing straight line up to 55 T. The H{sub c} value is close to those obtained in previous spin resonance studies in which a model of a spin-flop scenario was proposed to explain the field-dependent resonance spectra. With the earlier model a further transition at around 23 T was predicted; however, our observations did not show any plateau behaviors, saturation or other anomalies up to 55 T, suggesting that the further transition possibly exists in a much higher field region.

  20. High field magnetotransport and point contact Andreev reflection measurements on CuCr{sub 2}Se{sub 4} and CuCr{sub 2}Se{sub 3}Br—Degenerate magnetic semiconductor single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Borisov, K., E-mail: borisovk@tcd.ie; Coey, J. M. D.; Stamenov, P. [School of Physics and CRANN, Trinity College, Dublin 2 (Ireland); Alaria, J. [Department of Physics, University of Liverpool, Liverpool L69 7ZE (United Kingdom)

    2014-05-07

    Single crystals of the metallically degenerate fully magnetic semiconductors CuCr{sub 2}Se{sub 4} and CuCr{sub 2}Se{sub 3}Br have been prepared by the Chemical Vapour Transport method, using either Se or Br as transport agents. The high-quality, millimetre-sized, octahedrally faceted, needle- and platelet-shaped crystals are characterised by means of high field magnetotransport (μ{sub 0}H≤ 14 T) and Point Contact Andreev Reflection. The relatively high spin polarisation observed |P|>0.56, together with the relatively low minority carrier effective mass of 0.25 m{sub e}, and long scattering time  10{sup −13} s, could poise these materials for integration in low- and close-to-room temperature minority injection bipolar heterojunction transistor demonstrations.

  1. Chest computed tomography

    DEFF Research Database (Denmark)

    Loeve, Martine; Krestin, Gabriel P.; Rosenfeld, Margaret;

    2013-01-01

    are not suitable to study CF lung disease in young children. Chest computed tomography (CT) holds great promise for use as a sensitive surrogate endpoint in CF. A large body of evidence has been produced to validate the use of chest CT as primary endpoint to study CF lung disease. However, before chest CT can...

  2. Chest x-ray

    Science.gov (United States)

    Chest radiography; Serial chest x-ray; X-ray - chest ... You stand in front of the x-ray machine. You will be told to hold your breath when the x-ray is taken. Two images are usually taken. You will ...

  3. Ultra-High-Field MR Neuroimaging

    OpenAIRE

    Balchandani, P.; Naidich, T P

    2014-01-01

    At ultra-high magnetic fields, such as 7T, MR imaging can noninvasively visualize the brain in unprecedented detail and through enhanced contrast mechanisms. The increased SNR and enhanced contrast available at 7T enable higher resolution anatomic and vascular imaging. Greater spectral separation improves detection and characterization of metabolites in spectroscopic imaging. Enhanced blood oxygen level–dependent contrast affords higher resolution functional MR imaging. Ultra-high-field MR im...

  4. Evaluation of post-procedure changes in aneurysmal lumen following detachable coil-placement using multi-planar reconstruction of high-field (3.0T) magnetic resonance angiography

    International Nuclear Information System (INIS)

    Placement of detachable coil(s) for intracranial aneurysms has become one of the standard methods of management. Although detailed analysis of post-procedure changes in aneurysmal lumen is essential, technical difficulties often limit such evaluation. Development of higher magnetic field systems is steadily widening clinical usage of magnetic resonance imaging (MRI) primarily due to its significantly higher signal to noise ratio. In this study, we evaluated a multi-planar reconstruction (MPR) technique of magnetic resonance angiography (MRA) on a 3.0T system in an attempt to develop a routine method of post-procedure evaluation following detachable coil placement. Eleven patients with an intracranial aneurysm following placement of a Guglielmi detachable coil (GDC) participated in the study. Time of flight (TOF) magnetic resonance angiography (MRA) was obtained immediately after, and up to two years after coil embolisation utilising a GE 3.0T system. Data was analysed using standard maximum intensity projection (MIP) as well as the MPR technique and the results were compared to conventional catheter angiography. The study demonstrated that, compared to MIP, MPR can provide further information of alteration in aneurysm lumen, especially in analysis of jet of blood flow; thrombus formation; neck remnant or re-filling of blood; location and shape of coils including compaction; coil protrusion into the parent artery. Combined MPR/MIP analysis of high-field MRA appears to be a powerful non-invasive method for evaluating GDC-treatment that can potentially replace conventional catheter angiography in many clinical situations. (author)

  5. Chest X-Ray

    Medline Plus

    Full Text Available ... this Site RadiologyInfo.org is produced by: Image/Video Gallery Your radiologist explains chest x-ray. Transcript ... time! Spotlight Recently posted: Pediatric MRI Intravascular Ultrasound Video: Chest CT Video:Thyroid Ultrasound Video: Head CT ...

  6. Globally conditioned Granger causality in brain-brain and brain-heart interactions: a combined heart rate variability/ultra-high-field (7 T) functional magnetic resonance imaging study.

    Science.gov (United States)

    Duggento, Andrea; Bianciardi, Marta; Passamonti, Luca; Wald, Lawrence L; Guerrisi, Maria; Barbieri, Riccardo; Toschi, Nicola

    2016-05-13

    The causal, directed interactions between brain regions at rest (brain-brain networks) and between resting-state brain activity and autonomic nervous system (ANS) outflow (brain-heart links) have not been completely elucidated. We collected 7 T resting-state functional magnetic resonance imaging (fMRI) data with simultaneous respiration and heartbeat recordings in nine healthy volunteers to investigate (i) the causal interactions between cortical and subcortical brain regions at rest and (ii) the causal interactions between resting-state brain activity and the ANS as quantified through a probabilistic, point-process-based heartbeat model which generates dynamical estimates for sympathetic and parasympathetic activity as well as sympathovagal balance. Given the high amount of information shared between brain-derived signals, we compared the results of traditional bivariate Granger causality (GC) with a globally conditioned approach which evaluated the additional influence of each brain region on the causal target while factoring out effects concomitantly mediated by other brain regions. The bivariate approach resulted in a large number of possibly spurious causal brain-brain links, while, using the globally conditioned approach, we demonstrated the existence of significant selective causal links between cortical/subcortical brain regions and sympathetic and parasympathetic modulation as well as sympathovagal balance. In particular, we demonstrated a causal role of the amygdala, hypothalamus, brainstem and, among others, medial, middle and superior frontal gyri, superior temporal pole, paracentral lobule and cerebellar regions in modulating the so-called central autonomic network (CAN). In summary, we show that, provided proper conditioning is employed to eliminate spurious causalities, ultra-high-field functional imaging coupled with physiological signal acquisition and GC analysis is able to quantify directed brain-brain and brain-heart interactions reflecting

  7. Learning chest imaging

    Energy Technology Data Exchange (ETDEWEB)

    Pedrozo Pupo, John C. (ed.) [Magdalena Univ., Santa Maria (Colombia). Respire - Inst. for Respiratory Care

    2013-03-01

    Useful learning tool for practitioners and students. Overview of the imaging techniques used in chest radiology. Aid to the correct interpretation of chest X-ray images. Radiology of the thorax forms an indispensable element of the basic diagnostic process for many conditions and is of key importance in a variety of medical disciplines. This user-friendly book provides an overview of the imaging techniques used in chest radiology and presents numerous instructive case-based images with accompanying explanatory text. A wide range of clinical conditions and circumstances are covered with the aim of enabling the reader to confidently interpret chest images by correctly identifying structures of interest and the causes of abnormalities. This book, which will be an invaluable learning tool, forms part of the Learning Imaging series for medical students, residents, less experienced radiologists, and other medical staff. Learning Imaging is a unique case-based series for those in professional education in general and for physicians in prarticular.

  8. Chest X-Ray

    Medline Plus

    Full Text Available ... However, it’s important to consider the likelihood of benefit to your health. While a chest x-ray use a tiny dose of ionizing radiation, the benefit of an accurate diagnosis far outweighs any risk. ...

  9. Digital chest radiography

    DEFF Research Database (Denmark)

    Debess, Jeanne Elisabeth; Johnsen, Karen Kirstine; Thomsen, Henrik

    2015-01-01

    Background: Chest radiography is one of the most common examinations in radiology departments. In 2013 approximately 80,000 chest x-rays were performed on women in the fertile age. Even low dose for the examinationCorrect collimation Purpose: Quality improvement of basic radiography focusing...... on collimation and dose reduction in digital chest radiography Methods and Materials A retrospective study of digital chest radiography is performed to evaluate the primary x-ray tube collimation of the PA and lateral radiographs. Data from one hundred fifty self-reliant female patients between 15 and 55 years...... of age are included in the study. The clinical research is performed between September and November 2014 where 3rd year Radiography students collect data on four Danish x-ray departments using identical procedures under guidance of clinical supervisors. Optimal collimation is determined by European...

  10. Management of chest keloids

    Directory of Open Access Journals (Sweden)

    Kim June Kyu

    2011-04-01

    Full Text Available Abstract Keloid formation is one of the most challenging clinical problems in wound healing. With increasing frequency of open heart surgery, chest keloid formations are not infrequent in the clinical practice. The numerous treatment methods including surgical excision, intralesional steroid injection, radiation therapy, laser therapy, silicone gel sheeting, and pressure therapy underscore how little is understood about keloids. Keloids have a tendency to recur after surgical excision as a single treatment. Stretching tension is clearly associated with keloid generation, as keloids tend to occur on high tension sites such as chest region. The authors treated 58 chest keloid patients with surgical excision followed by intraoperative and postoperative intralesional steroid injection. Even with minor complications and recurrences, our protocol results in excellent outcomes in cases of chest keloids.

  11. Cardiac injuries in blunt chest trauma

    Directory of Open Access Journals (Sweden)

    Tobon-Gomez Catalina

    2009-09-01

    Full Text Available Abstract Blunt chest traumas are a clinical challenge, both for diagnosis and treatment. The use of Cardiovascular Magnetic Resonance can play a major role in this setting. We present two cases: a 12-year-old boy and 45-year-old man. Late gadolinium enhancement imaging enabled visualization of myocardial damage resulting from the trauma.

  12. Cardiac injuries in blunt chest trauma

    OpenAIRE

    Tobon-Gomez Catalina; Huguet Marina; Bijnens Bart H; Frangi Alejandro F; Petit Marius

    2009-01-01

    Abstract Blunt chest traumas are a clinical challenge, both for diagnosis and treatment. The use of Cardiovascular Magnetic Resonance can play a major role in this setting. We present two cases: a 12-year-old boy and 45-year-old man. Late gadolinium enhancement imaging enabled visualization of myocardial damage resulting from the trauma.

  13. The Pioneer XI high field fluxgate magnetometer

    Science.gov (United States)

    Acuna, M. A.; Ness, N. F.

    1975-01-01

    The high field fluxgate magnetometer experiment flown aboard the Pioneer XI spacecraft is described. This extremely simple instrument was used to extend the spacecraft's upper-limit measurement capability by approximately an order of magnitude (from 0.14 mT to 1.00 mT) with minimum power and volume requirements. This magnetometer was designed to complement the low-field measurements provided by a helium vector magnetometer and utilizes magnetic ring core sensors with biaxial orthogonal sense coils. The instrument is a single-range, triaxial-fluxgate magnetometer capable of measuring fields of up to 1 mT along each orthogonal axis, with a maximum resolution of 1 microT.

  14. Acute diaphragmatic paralysis caused by chest-tube trauma to phrenic nerve

    International Nuclear Information System (INIS)

    A 31/2-year-old child developed unilateral diaphragmatic paralysis after chest drain insertion. Plain chest X-ray demonstrated paravertebral positioning of the chest-tube tip, and magnetic resonance imaging revealed hematomas in the region of the chest-tube tip and the phrenic nerve fibers. The trauma to the phrenic nerve was apparently secondary to malposition of the chest tube. This is a rare complication and has been reported mainly in neonates. Radiologists should notify the treating physicians that the correct position of a chest drain tip is at least 2 cm distant from the vertebrae. (orig.)

  15. Imaging of Chest Wall Lesions in Children

    Directory of Open Access Journals (Sweden)

    A. Hekmatnia

    2008-01-01

    Full Text Available Chest wall lesions in childhood include a wide range of pathologies; Benign lesions include lipoma, neurofibroma, lymphangioma, hemangioma, and mesenchymal hamartoma."nMalignant lesions include Neuroblastoma, Rhabdo-myosarcoma, Ewing sarcoma, and Askin tumor."nSystemic diseases such as leukemia, lymphoma, Langerhans cell histiocytosis, and also infections such as tuberculosis, and actinomycosis may also cause chest wall lesions."nThe imaging characteristics of these lesions are re-viewed, but only a minority of the lesions shows diagnostic imaging features, and most of lesions re-quire biopsy and histopathological examination for "ndefinitive diagnosis."nThe role of different modalities is discussed with an emphasis on magnetic resonance imaging for demonstrating lesion morphology and local spread. Computed tomography and neuclear medicine being used mainly to assess remote disease."nIn this lecture, we discuss about imaging of chest wall lesions in children.

  16. Digital chest radiography

    DEFF Research Database (Denmark)

    Debess, Jeanne Elisabeth; Vejle-Sørensen, Jens Kristian; Thomsen, Henrik;

    2015-01-01

    of clinical supervisors. Optimal collimation is determined by European and Regional Danish guidelines. The areal between current and optimal collimation is calculated. The experimental research is performed in September - October 2014 Siemens Axiom Aristos digital radiography system DR using 150 kV, 1,25 -3......Purpose: Quality improvement of basic radiography focusing on collimation and dose reduction in digital chest radiography Methods and Materials:A retrospective study of digital chest radiography is performed to evaluate the primary x-ray tube collimation of the PA and lateral radiographs. Data from...

  17. Anterior chest wall examination reviewed

    Directory of Open Access Journals (Sweden)

    F. Trotta

    2011-09-01

    Full Text Available Anterior chest wall involvement is not infrequently observed within inflammatory arthropaties, particularly if one considers seronegative spondiloarthritides and SAPHO syndrome. Physical examination is unreliable and conventional X-rays analysis is an unsatisfactory tool during diagnostic work-up of this region. Scintigraphic techniques yield informations both on the activity and on the anatomical extent of the disease while computerized tomography visualize the elementary lesions, such as erosions, which characterize the process. Moreover, when available, magnetic resonance imaging couple the ability to finely visualize such lesions with the possibility to show early alterations and to characterize the “activity” of the disease, presenting itself as a powerful tool both for diagnosis and follow-up. This review briefly shows the applications of imaging techniques for the evaluation of the anterior chest wall focusing on what has been done in the SAPHO syndrome which can be considered prototypical for this regional involvement since it is the osteo-articular target mainly affected by the disease.

  18. High field, high repetition rate kicker

    CERN Document Server

    Ishi, Y; Muto, M; Shirakabe, Y; Takagi, A

    2001-01-01

    New kicker magnet systems and their related technologies are being developed and tested at KEK. The kickers are to be used both for the injection and for the fast extraction of two rings, the 50 GeV proton synchrotron in the 'Joint Project' of JAERI-KEK and the PRISM/FFAG ring for the muon beam. In order to obtain a sufficient kick on the high-intensity beam in the 50 GeV proton ring, the kicker systems must have both large apertures and high fields. In addition to this, the PRISM/FFAG ring demands muon beams with a high repetition rate of injection and extraction. The requested repetition rate is 1 kHz or higher. In order to fulfill those demands, new technologies have been introduced and are now being tested. Among them are high-power IGBT modules, a subordinated-gating system, 1 kHz repetition pulsed power supply, and kickers with magnetic-alloy cores used as return yokes.

  19. Chest X-Ray

    Medline Plus

    Full Text Available ... Pediatric Ultrasound Video: Angioplasty & vascular stenting Video: Arthrography Radiology and You About this Site RadiologyInfo.org is ... radiologist explains chest x-ray. Transcript Welcome to Radiology Info dot org! Hello, I’m Dr. Geoffrey ...

  20. Chest X-Ray

    Medline Plus

    Full Text Available ... this Site RadiologyInfo.org is produced by: Image/Video Gallery Your radiologist explains chest x-ray. Transcript ... Recently posted: Focused Ultrasound for Uterine Fibroids Dementia Video: General Ultrasound Video: Pediatric Nuclear Medicine Radiology and ...

  1. High field laser heated solenoids

    International Nuclear Information System (INIS)

    A 10 kJ pulsed CO2 laser and 3.8 cm bore, 15 T, 8 μs rise time, 1-m long fast solenoid facility has been constructed to demonstrate the feasibility of using long wavelength lasers to heat magnetically confined plasmas. The most critical physics requirement is the necessity of creating and maintaining an on-axis electron density minimum to trap the axially directed laser beam. Satisfaction of this requirement has been demonstrated by heating 1.5 Torr deuterium fill plasmas in 2.7 cm bore plasma tubes to line energies of approximately 1 kJ/m. (Auth.)

  2. High Field Phenomena of Qubits

    CERN Document Server

    van Tol, J; Takahashi, S; McCamey, D R; Boehme, C; Zvanut, M E

    2009-01-01

    Electron and nuclear spins are very promising candidates to serve as quantum bits (qubits) for proposed quantum computers, as the spin degrees of freedom are relatively isolated from their surroundings, and can be coherently manipulated e.g. through pulsed EPR and NMR. For solid state spin systems, impurities in crystals based on carbon and silicon in various forms have been suggested as qubits, and very long relaxation rates have been observed in such systems. We have investigated a variety of these systems at high magnetic fields in our multi-frequency pulsed EPR/ENDOR spectrometer. A high magnetic field leads to large electron spin polarizations at helium temperatures giving rise to various phenomena that are of interest with respect to quantum computing. For example, it allows the initialization of the both the electron spin as well as hyperfine-coupled nuclear spins in a well defined state by combining millimeter and RF radiation; it can increase the T2 relaxation times by eliminating decoherence due to ...

  3. High field superconductor development and understanding

    Energy Technology Data Exchange (ETDEWEB)

    Larbalestier, David C. [Florida State Univ., Tallahassee, FL (United States); Lee, Peter J. [Florida State Univ., Tallahassee, FL (United States); Tarantini, Chiara [Florida State Univ., Tallahassee, FL (United States)

    2014-09-28

    All present circular accelerators use superconducting magnets to bend and to focus the particle beams. The most powerful of these machines is the large hadron collider (LHC) at CERN. The main ring dipole magnets of the LHC are made from Nb-Ti but, as the machine is upgraded to higher luminosity, more powerful magnets made of Nb3Sn will be required. Our work addresses how to make the Nb3Sn conductors more effective and more suitable for use in the LHC. The most important property of the superconducting conductor used for an accelerator magnet is that it must have very high critical current density, the property that allows the generation of high magnetic fields in small spaces. Nb3Sn is the original high field superconductor, the material which was discovered in 1960 to allow a high current density in the field of about 9 T. For the high luminosity upgrade of the LHC, much higher current densities in fields of about 12 Tesla will be required. The critical value of the current density is of order 2600 A/mm2 in a field of 12 Tesla. But there are very important secondary factors that complicate the attainment of this critical current density. The first is that the effective filament diameter must be no larger than about 40 µm. The second factor is that 50% of the cross-section of the Nb3Sn conductor that is pure copper must be protected from any poisoning by any Sn leakage through the diffusion barrier that protects the package of niobium and tin from which the Nb3Sn is formed by a high temperature reaction. These three, somewhat conflicting requirements, mean that optimization of the conductor is complex. The work described in this contract report addresses these conflicting requirements. They show that very sophisticated characterizations can uncover the way to satisfy all 3 requirements and they also suggest that the ultimate optimization of Nb3Sn is still not yet in sight

  4. Endometriose pélvica: comparação entre imagens por ressonância magnética de baixo campo (0,2 T e alto campo (1,5 T Pelvic endometriosis: a comparison between low-field (0.2 T and high-field (1.5 T magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Karine Minaif

    2008-12-01

    Full Text Available OBJETIVO: Comparar a ressonância de baixo campo (0,2 T com a de alto campo (1,5 T na avaliação da endometriose pélvica e adenomiose. MATERIAIS E MÉTODOS: Foram estudadas, prospectivamente, 27 pacientes do sexo feminino com suspeita clínica de endometriose, realizando-se exames de ressonância magnética de alto campo e baixo campo. Um mesmo radiologista realizou a leitura dos exames, iniciando pelo baixo campo, seguido pelo alto campo, usando como padrão-ouro o alto campo. RESULTADOS: Das 27 pacientes estudadas, 18 (66,7% apresentaram alguma lesão indicativa de endometriose nos exames realizados no alto campo. Foram corretamente diagnosticados pelo baixo campo 14 destas pacientes. Endometriomas, lesões tubárias e focos de endometriose maiores do que 7 mm identificados pelo alto campo foram também identificados no baixo campo, com acurácia, sensibilidade e especificidade de 100%. Das nove pacientes com adenomiose caracterizadas pelo alto campo, oito foram corretamente identificadas pelo baixo campo, com acurácia, sensibilidade e especificidade de 88,9%. CONCLUSÃO: A ressonância de baixo campo apresentou baixa sensibilidade na detecção de pequenos focos de endometriose, alta sensibilidade na detecção de endometriomas e focos de endometriose grandes, e boa acurácia na detecção da adenomiose quando comparada com a ressonância de alto campo.OBJECTIVE: To compare low-field (0.2 T with high-field (1.5 T magnetic resonance imaging in the assessment of pelvic endometriosis and adenomyosis. MATERIALS AND METHODS: Twenty-seven female patients with clinically suspected endometriosis were prospectively evaluated by means of high-field and low-field magnetic resonance imaging. The reading of the images was performed by a single radiologist, initiating by the low-field, followed by the high-field images. High-field magnetic resonance imaging was utilized as the golden-standard. RESULTS: Among the 27 patients included in the present study

  5. Sandstorm in the chest?

    Directory of Open Access Journals (Sweden)

    Talluri MR

    2011-07-01

    Full Text Available A 32 year old female presented with dry cough and progressive breathlessness of one year duration. There was no history suggestive of collagen vascular disease, lung parenchymal infection or allergic airway disease. Clinical evaluation showed basal fine inspiratory crepitations. Radiographic examination of the chest revealed a black pleura line and lung parenchymal calcification. CT scan of the chest demonstrated nodular calcification of lung parenchyma with a “crazy pavement” pattern, which is suggestive of alveolar calcification. Pulmonary function test showed a severe restrictive defect. On transbronchial lung biopsy calcific spherules suggestive of the alveolar microlithiasis were seen. Diagnosis of pulmonary alveolar microlithiasis was made and symptomatic treatment was given, as there is no specific therapy available. The case illustrates an unusual cause of shortness of breath in a young female with striking radiographic features.

  6. CHEST PHYSIOTHERAPY FOR INFANTS

    OpenAIRE

    Preeti S. Christian (M.P.T Cardiopulmonary Conditions)

    2014-01-01

    In the normal lung, secretions are removed by Mucociliary activity, normal breathing cycles, and cough. In disease, increased secretion viscosity and volume, dyskinesia of the cilia, and ineffective cough combine to reduce the ability to clear secretions, and may increase exacerbations and infections. Many chest physiotherapy techniques like postural drainage, percussion and vibration are used since many years. These techniques are derived from adult studies but these techniques are quite str...

  7. HIGH FIELD Q-SLOPE AND THE BAKING EFFECT

    Energy Technology Data Exchange (ETDEWEB)

    Ciovati, Gianluigi [JLAB

    2009-11-01

    The performance of SRF cavities made of bulk Nb at high fields (peak surface magnetic field greater than about 90 mT) is characterized by exponentially increasing RF losses (high-field Q-slope), in the absence of field emission, which are often mitigated by a low temperature (100-140 °C, 12-48h) baking. In this contribution, recent experimental results and phenomenological models to explain this effect will be briefly reviewed. New experimental results on the high-field Q-slope will be presented for cavities that had been heat treated at high temperature in the presence of a small partial pressure of nitrogen. Improvement of the cavity performances have been obtained, while surface analysis measurements on Nb samples treated with the cavities revealed significantly lower hydrogen concentration than for samples that followed standard cavity treatments.

  8. High field, low current operation of engineering test reactors

    International Nuclear Information System (INIS)

    Steady state engineering test reactors with high field, low current operation are investigated and compared to high current, lower field concepts. Illustrative high field ETR parameters are R = 3 m, α ∼ 0.5 m, B ∼ 10 T, β = 2.2% and I = 4 MA. For similar wall loading the fusion power of an illustrative high field, low current concept could be about 50% that of a lower field device like TIBER II. This reduction could lead to a 50% decrease in tritium consumption, resulting in a substantial decrease in operating cost. Furthermore, high field operation could lead to substantially reduced current drive requirements and cost. A reduction in current drive source power on the order of 40 to 50 MW may be attainable relative to a lower field, high current design like TIBER II implying a possible cost savings on the order of $200 M. If current drive is less efficient than assumed, the savings could be even greater. Through larger β/sub p/ and aspect ratio, greater prospects for bootstrap current operation also exist. Further savings would be obtained from the reduced size of the first wall/blanket/shield system. The effects of high fields on magnet costs are very dependent on technological assumptions. Further improvements in the future may lie with advances in superconducting and structural materials

  9. The neonatal chest

    Energy Technology Data Exchange (ETDEWEB)

    Lobo, Luisa [Servico de Imagiologia Geral do Hospital de Santa Maria, Av. Prof. Egas Moniz, 1649-035 Lisbon (Portugal)]. E-mail: mluisalobo@gmail.com

    2006-11-15

    Lung diseases represent one of the most life threatening conditions in the newborn. Important progresses in modern perinatal care has resulted in a significantly improved survival and decreased morbidity, in both term and preterm infants. Most of these improvements are directly related to the better management of neonatal lung conditions, and infants of very low gestational ages are now surviving. This article reviews the common spectrum of diseases of the neonatal lung, including medical and surgical conditions, with emphasis to the radiological contribution in the evaluation and management of these infants. Imaging evaluation of the neonatal chest, including the assessment of catheters, lines and tubes are presented.

  10. The neonatal chest

    International Nuclear Information System (INIS)

    Lung diseases represent one of the most life threatening conditions in the newborn. Important progresses in modern perinatal care has resulted in a significantly improved survival and decreased morbidity, in both term and preterm infants. Most of these improvements are directly related to the better management of neonatal lung conditions, and infants of very low gestational ages are now surviving. This article reviews the common spectrum of diseases of the neonatal lung, including medical and surgical conditions, with emphasis to the radiological contribution in the evaluation and management of these infants. Imaging evaluation of the neonatal chest, including the assessment of catheters, lines and tubes are presented

  11. American College of Chest Physicians

    Science.gov (United States)

    ... American College of Chest Physicians and Sunovion announce strategic initiative focused on the importance of drug delivery in the management of COPD Sunovion Pharmaceuticals, Inc. (Sunovion) and the ...

  12. High-field spin dynamics of antiferromagnetic quantum spin chains

    DEFF Research Database (Denmark)

    Enderle, M.; Regnault, L.P.; Broholm, C.;

    2000-01-01

    The characteristic internal order of macroscopic quantum ground states in one-dimensional spin systems is usually not directly accessible, but reflected in the spin dynamics and the field dependence of the magnetic excitations. In high magnetic fields quantum phase transitions are expected. We...... present recent work on the high-field spin dynamics of the S = I antiferromagnetic Heisenberg chains NENP (Haldane ground state) and CsNiCl3 (quasi-1D HAF close to the quantum critical point), the uniform S = 1/2 chain CTS, and the spin-Peierls system CuGeO3. (C) 2000 Elsevier Science B,V. All rights...

  13. Optimizing brain tumor resection. High-field interventional MR imaging.

    Science.gov (United States)

    Tummala, R P; Chu, R M; Liu, H; Truwit, C L; Hall, W A

    2001-11-01

    High-field strength iMRI guidance is an effective tool for brain tumor resection. Although its use lengthens the average time for a craniotomy, the reward is a more extensive tumor excision compared with conventional neurosurgery without an increased risk to the patient (Table 4). Although intraoperative patient transfer into and out of the magnet is cumbersome, the possibility for complete resection, especially for a low-grade glioma, makes the effort worthwhile. The cost and technical support required for this system presently limits its use to only a few sites worldwide. As with any technology, further refinements will make this system less expensive and more attainable. Practical consideration aside, high-field strength iMRI is presently [table: see text] the most effective tool available for brain tumor resection. Because of its novelty, future studies are necessary to determine if this technology lowers the incidence of and extends the duration to tumor recurrence as the preliminary data in children suggests. These are the ultimate measures of efficacy for any brain tumor treatment. Based on the rapid advancement of technology, will today's high-field strength interventional magnet become tomorrow's low-field system? Very high-field strength designs may improve diagnostic capabilities through higher resolution, but their interventional applications may be hindered by increased sensitivity for clinically insignificant abnormalities and decreased specificity for clinically relevant lesions. As new technology is developed, clinicians must continue to explore and refine the existing high-field strength iMRI to make it cost-effective and widely applicable.

  14. SU-E-J-03: Characterization of the Precision and Accuracy of a New, Preclinical, MRI-Guided Focused Ultrasound System for Image-Guided Interventions in Small-Bore, High-Field Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Ellens, N [Johns Hopkins University, Baltimore, Maryland (United States); Farahani, K [National Cancer Institute, Bethesda, MD (United States)

    2015-06-15

    Purpose: MRI-guided focused ultrasound (MRgFUS) has many potential and realized applications including controlled heating and localized drug delivery. The development of many of these applications requires extensive preclinical work, much of it in small animal models. The goal of this study is to characterize the spatial targeting accuracy and reproducibility of a preclinical high field MRgFUS system for thermal ablation and drug delivery applications. Methods: The RK300 (FUS Instruments, Toronto, Canada) is a motorized, 2-axis FUS positioning system suitable for small bore (72 mm), high-field MRI systems. The accuracy of the system was assessed in three ways. First, the precision of the system was assessed by sonicating regular grids of 5 mm squares on polystyrene plates and comparing the resulting focal dimples to the intended pattern, thereby assessing the reproducibility and precision of the motion control alone. Second, the targeting accuracy was assessed by imaging a polystyrene plate with randomly drilled holes and replicating the hole pattern by sonicating the observed hole locations on intact polystyrene plates and comparing the results. Third, the practicallyrealizable accuracy and precision were assessed by comparing the locations of transcranial, FUS-induced blood-brain-barrier disruption (BBBD) (observed through Gadolinium enhancement) to the intended targets in a retrospective analysis of animals sonicated for other experiments. Results: The evenly-spaced grids indicated that the precision was 0.11 +/− 0.05 mm. When image-guidance was included by targeting random locations, the accuracy was 0.5 +/− 0.2 mm. The effective accuracy in the four rodent brains assessed was 0.8 +/− 0.6 mm. In all cases, the error appeared normally distributed (p<0.05) in both orthogonal axes, though the left/right error was systematically greater than the superior/inferior error. Conclusions: The targeting accuracy of this device is sub-millimeter, suitable for many

  15. SU-E-J-03: Characterization of the Precision and Accuracy of a New, Preclinical, MRI-Guided Focused Ultrasound System for Image-Guided Interventions in Small-Bore, High-Field Magnets

    International Nuclear Information System (INIS)

    Purpose: MRI-guided focused ultrasound (MRgFUS) has many potential and realized applications including controlled heating and localized drug delivery. The development of many of these applications requires extensive preclinical work, much of it in small animal models. The goal of this study is to characterize the spatial targeting accuracy and reproducibility of a preclinical high field MRgFUS system for thermal ablation and drug delivery applications. Methods: The RK300 (FUS Instruments, Toronto, Canada) is a motorized, 2-axis FUS positioning system suitable for small bore (72 mm), high-field MRI systems. The accuracy of the system was assessed in three ways. First, the precision of the system was assessed by sonicating regular grids of 5 mm squares on polystyrene plates and comparing the resulting focal dimples to the intended pattern, thereby assessing the reproducibility and precision of the motion control alone. Second, the targeting accuracy was assessed by imaging a polystyrene plate with randomly drilled holes and replicating the hole pattern by sonicating the observed hole locations on intact polystyrene plates and comparing the results. Third, the practicallyrealizable accuracy and precision were assessed by comparing the locations of transcranial, FUS-induced blood-brain-barrier disruption (BBBD) (observed through Gadolinium enhancement) to the intended targets in a retrospective analysis of animals sonicated for other experiments. Results: The evenly-spaced grids indicated that the precision was 0.11 +/− 0.05 mm. When image-guidance was included by targeting random locations, the accuracy was 0.5 +/− 0.2 mm. The effective accuracy in the four rodent brains assessed was 0.8 +/− 0.6 mm. In all cases, the error appeared normally distributed (p<0.05) in both orthogonal axes, though the left/right error was systematically greater than the superior/inferior error. Conclusions: The targeting accuracy of this device is sub-millimeter, suitable for many

  16. Advanced high-field coil designs: 20 TESLA

    International Nuclear Information System (INIS)

    This chapter examines the technology required for producing very high-field barrier solenoid coils. Topics considered include superfluid helium for advanced magnets, conductor reinforcement, the computer programs ADVMAGNET and CONDUCTOR, a sample coil design (20-T, 2-m diameter bore), and future research development needs. CONDUCTOR designs the conductor windings, insulation, stainless steel reinforcing, and coolant flow channels. ADVMAGNET takes the coil pack current densities given by CONDUCTOR, and derives the graded subcoil geometries for producing the required central on-axis magnetic field. The main goal of future research to optimize coil designs is to reduce the magnet's size. It is concluded that the designed magnets will greatly contribute to the national mirror fusion program

  17. Ressonância magnética do tórax: aplicações tradicionais e novas, com ênfase em pneumologia Magnetic resonance imaging of the chest: current and new applications, with an emphasis on pulmonology

    Directory of Open Access Journals (Sweden)

    Marcel Koenigkam Santos

    2011-04-01

    Full Text Available O objetivo deste estudo de revisão foi apresentar as principais aplicações da ressonância magnética (RM no estudo do tórax, incluindo a descrição de novas técnicas. Na ultima década, esse método teve grande evolução, com novos equipamentos, incluindo a interconexão simultânea de bobinas e a movimentação da mesa simultaneamente à aquisição das imagens, além do advento de novas técnicas rápidas de aquisição de imagem, tais como imagem paralela e aquisição parcial de dados, com ou sem utilização de apneia, somando-se ainda a introdução de novos agentes de contraste. Todos esses avanços fizeram com que a RM tenha ganhado espaço no estudo de diferentes patologias do tórax, incluindo as doenças pulmonares. Atualmente, a RM pode ser considerada a modalidade de escolha para a avaliação das lesões mediastinais, da parede torácica e dos tumores do sulco superior, mas também pode auxiliar no diagnóstico de doenças pulmonares, pleurais, cardíacas e da vasculatura pulmonar. A angiografia pulmonar por RM pode ser utilizada na avaliação de várias doenças vasculares pulmonares, e seu papel no estudo do tromboembolismo vem crescendo. A RM cardíaca, devido à possibilidade de avaliação morfológica e funcional em um mesmo exame, também já faz parte da rotina clínica na investigação de muitas patologias cardíacas. Por fim, o papel da RM vem sendo ampliado para a identificação e caracterização de nódulos pulmonares, avaliação das doenças das vias aéreas e caracterização dos derrames pleurais.The objective of the present review study was to present the principal applications of magnetic resonance imaging (MRI of the chest, including the description of new techniques. Over the past decade, this method has evolved considerably because of the development of new equipment, including the simultaneous interconnection of phased-array multiple radiofrequency receiver coils and remote control of the table

  18. High field superconductor development and understanding project, Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Larbalestier, David C.; Lee, Peter J.

    2009-07-15

    Over 25 years the Applied Superconductivity Center at the University of Wisconsin-Madison provided a vital technical resource to the High Energy Physics community covering development in superconducting strand for HEP accelerator magnet development. In particular the work of the group has been to develop the next generation of high field superconductors for high field application. Grad students Mike Naus, Chad Fischer, Arno Godeke and Matt Jewell improved our understanding of the microstructure and microchemistry of Nb3Sn and their impact on the physical and mechanical properties. The success of this work has led to the continued funding of this work at the ASC after it moved to the NHMFL and also to direct funding from BNL for some aspects of Nb3Sn cable evaluation.

  19. Radiology illustrated. Chest radiology

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyung Soo [Sungkyunkwan Univ. School of Medicine, Seoul (Korea, Republic of). Dept. of Radiology; Han, Joungho [Sungkyunkwan Univ. School of Medicine, Seoul (Korea, Republic of). Dept. of Pathology; Chung, Man Pyo [Sungkyunkwan Univ. School of Medicine, Seoul (Korea, Republic of). Dept. of Medicine; Jeong, Yeon Joo [Pusan National Univ. Hospital, Busan (Korea, Republic of). Dept. of Radiology

    2014-04-01

    Pattern approach to the diagnosis of lung diseases based on CT scan appearances. Guide to quick and reliable differential diagnosis. CT-pathology correlation. Emphasis on state-of-the-art MDCT. The purpose of this atlas is to illustrate how to achieve reliable diagnoses when confronted by the different abnormalities, or ''disease patterns'', that may be visualized on CT scans of the chest. The task of pattern recognition has been greatly facilitated by the advent of multidetector CT (MDCT), and the focus of the book is very much on the role of state-of-the-art MDCT. A wide range of disease patterns and distributions are covered, with emphasis on the typical imaging characteristics of the various focal and diffuse lung diseases. In addition, clinical information relevant to differential diagnosis is provided and the underlying gross and microscopic pathology is depicted, permitting CT-pathology correlation. The entire information relevant to each disease pattern is also tabulated for ease of reference. This book will be an invaluable handy tool that will enable the reader to quickly and easily reach a diagnosis appropriate to the pattern of lung abnormality identified on CT scans.

  20. Chest radiographic findings of leptospirosis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Mee Hyun; Jung, Hee Tae; Lee, Young Joong; Yoon, Jong Sup [Hallym University College of Medicine, Seoul (Korea, Republic of)

    1986-04-15

    1. A study on chest radiographic findings of 54 cases with pneumonia like symptoms was performed. Of 54 cases, 8 cases were confirmed to be leptospirosis and 7 cases were leptospirosis combined with Korean hemorrhagic fever. 2. Of 8 cases of leptospirosis, 4 cases showed abnormal chest radiographic findings: acinar nodular type 2, massive confluent consolidation type 2. Of 7 cases of leptospirosis combined with Korean hemorrhagic fever: acinar nodular type 3, massive confluent consolidation type 1, and increased interstitial markings type 1 respectively. 3. It was considered to be difficult to diagnose the leptospirosis on chest radiographic findings alone, especially the case combined with Korean hemorrhagic fever.

  1. High-field proton MRS of human brain

    Energy Technology Data Exchange (ETDEWEB)

    Di Costanzo, Alfonso E-mail: alfonso.dicostanzo@unina2.it; Trojsi, F.; Tosetti, M.; Giannatempo, G.M.; Nemore, F.; Piccirillo, M.; Bonavita, S.; Tedeschi, G.; Scarabino, T

    2003-11-01

    Proton magnetic resonance spectroscopy ({sup 1}H-MRS) of the brain reveals specific biochemical information about cerebral metabolites, which may support clinical diagnoses and enhance the understanding of neurological disorders. The advantages of performing {sup 1}H-MRS at higher field strengths include better signal to noise ratio (SNR) and increased spectral, spatial and temporal resolution, allowing the acquisition of high quality, easily quantifiable spectra in acceptable imaging times. In addition to improved measurement precision of N-acetylaspartate, choline, creatine and myo-inositol, high-field systems allow the high-resolution measurement of other metabolites, such as glutamate, glutamine, {gamma}-aminobutyric acid, scyllo-inositol, aspartate, taurine, N-acetylaspartylglutamate, glucose and branched amino acids, thus extending the range of metabolic information. However, these advantages may be hampered by intrinsic field-dependent technical difficulties, such as decreased T2 signal, chemical shift dispersion errors, J-modulation anomalies, increased magnetic susceptibility, eddy current artifacts, limitations in the design of homogeneous and sensitive radiofrequency (RF) coils, magnetic field instability and safety issues. Several studies demonstrated that these limitations could be overcome, suggesting that the appropriate optimization of high-field {sup 1}H-MRS would expand the application in the fields of clinical research and diagnostic routine.

  2. Interpretation of neonatal chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hye Kyung [Dept. of Radiology, Kangwon National University Hospital, Chuncheon (Korea, Republic of)

    2016-05-15

    Plain radiographs for infants in the neonatal intensive care unit are obtained using the portable X-ray equipment in order to evaluate the neonatal lungs and also to check the position of the tubes and catheters used for monitoring critically-ill neonates. Neonatal respiratory distress is caused by a variety of medical or surgical disease conditions. Clinical information about the gestational week, respiratory symptoms, and any events during delivery is essential for interpretation of the neonatal chest radiographs. Awareness of common chest abnormality in the prematurely born or term babies is also very important for chest evaluation in the newborn. Furthermore, knowledge about complications such as air leaks and bronchopulmonary dysplasia following treatment are required to accurately inform the clinicians. The purpose of this article was to briefly review radiographic findings of chest diseases in newborns that are relatively common in daily practice.

  3. Chest Pain (Beyond the Basics)

    Science.gov (United States)

    ... number of problems related to the stomach and intestines can cause pain that spreads to or even begins in the chest, including ulcers, gallbladder disease, pancreatitis, and irritable bowel syndrome. (See "Patient information: Peptic ulcer disease (Beyond the ...

  4. Metal-Metal Interactions in Trinuclear Copper(II) Complexes [Cu3(RCOO)4(H2TEA)2] and Binuclear [Cu2(RCOO)2(H2TEA)2]. Syntheses and Combined Structural, Magnetic, High-Field Electron Paramagnetic Resonance, and Theoretical Studies.

    Science.gov (United States)

    Ozarowski, Andrew; Calzado, Carmen J; Sharma, Raj Pal; Kumar, Santosh; Jezierska, Julia; Angeli, Celestino; Spizzo, Federico; Ferretti, Valeria

    2015-12-21

    The trinuclear [Cu3(RCOO)4(H2TEA)2] copper(II) complexes, where RCOO(-) = 2-furoate (1), 2-methoxybenzoate (2), and 3-methoxybenzoate (3, 4), as well as dimeric species [Cu2(H2TEA)2(RCOO)2]·2H2O, have been prepared by adding triethanolamine (H3TEA) at ambient conditions to hydrated Cu(RCOO)2 salts. The newly synthesized complexes have been characterized by elemental analyses, spectroscopic techniques (IR and UV-visible), magnetic susceptibility, single crystal X-ray structure determination and theoretical calculations, using a Difference Dedicated Configuration Interaction approach for the evaluation of magnetic coupling constants. In 1 and 2, the central copper atom lies on an inversion center, while in the polymorphs 3 and 4, the three metal centers are crystallographically independent. The zero-field splitting parameters of the trimeric compounds, D and E, were derived from high-field, high-frequency electron paramagnetic resonance spectra at temperatures ranging from 3 to 290 K and were used for the interpretation of the magnetic data. It was found that the dominant interaction between the terminal and central Cu sites J12 is ferromagnetic in nature in all complexes, even though differences have been found between the symmetrical or quasi-symmetrical complexes 1-3 and non-symmetrical complex 4, while the interaction between the terminal centers, J23, is negligible.

  5. Discrimination of soybean oil adulterated frying oil by high-field nuclear magnetic resonance%煎炸老油掺伪大豆油的高场核磁检测

    Institute of Scientific and Technical Information of China (English)

    李玉邯; 陈宇飞; 杨柳; 王维坚

    2016-01-01

    通过高场核磁共振仪检测了纯大豆油和掺伪了煎炸老油的大豆油并对谱图进行积分。通过谱图对比发现了三个鉴别指标,第一个鉴别指标是在δ=1.58处,纯大豆油有明显特征峰,而煎炸老油在该处无特征峰;第二个鉴别指标是在δ=2.77~2.84处,纯大豆油特征峰的积分面积高于掺伪了煎炸老油的大豆油(添加50%煎炸老油积分面积为1.51,纯大豆油积分面积为2.04),并且随着煎炸老油添加量的增加积分面积逐渐减小;第三个鉴别指标是在δ=5.25~5.42处,纯大豆油特征峰的积分面积明显高于掺伪了煎炸老油的大豆油(添加50%煎炸老油积分面积为3.98,纯大豆油积分面积为4.87),而且也随着煎炸老油添加量的增加积分面积逐渐减小。%The pure soybean oil and frying soybean oil were detected by high–field nuclear magnetic resonance instrument and the spectrograms were integrated. There were three identification methods. The first one was characteristic peak atδ=1.58 which could be detected obviously in the pure oil and couldn’t be detected in frying soybean oil. The second was atδ=2.77~2.84,where the integral area of pure soybean was higher than the frying oil (the integral area of add 50%frying oil was 1.51,and the integral area of pure soybean oil was 2.04). The third was atδ=5.25~5.42,where the integral area of pure soybean was also significantly higher than the frying oil(the integral area of add 50%frying oil was 3.98,the integral area of pure soybean oil was 4.87). And with the addition of frying oil,the integral area decreased.

  6. Lymphomas presenting as chest wall tumors

    OpenAIRE

    Witte, Biruta; Hürtgen, Martin

    2006-01-01

    Four cases of thoracic lymphoma mimicking chest wall tumors are presented. As resection is not the treatment of first choice in lymphomas, pretherapeutical evaluation of chest wall tumors should include a thoroughly staging and a biopsy for histopathological diagnosis. Chest wall destruction due to an anterior mediastinal mass, or a chest wall tumor associated with mediastinal lymph node enlargement, could be suspicious of thoracic lymphoma. Lymphoma with chest wall involvement mostly turns o...

  7. Imaging of blunt chest trauma

    Energy Technology Data Exchange (ETDEWEB)

    Wicky, S.; Wintermark, M.; Schnyder, P.; Capasso, P.; Denys, A. [Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland). Dept. of Radiology

    2000-10-01

    In western European countries most blunt chest traumas are associated with motor vehicle and sport-related accidents. In Switzerland, 39 of 10,000 inhabitants were involved and severely injured in road accidents in 1998. Fifty two percent of them suffered from blunt chest trauma. According to the Swiss Federal Office of Statistics, traumas represented in men the fourth major cause of death (4 %) after cardiovascular disease (38 %), cancer (28 %), and respiratory disease (7 %) in 1998. The outcome of chest trauma patients is determined mainly by the severity of the lesions, the prompt appropriate treatment delivered on the scene of the accident, the time needed to transport the patient to a trauma center, and the immediate recognition of the lesions by a trained emergency team. Other determining factors include age as well as coexisting cardiac, pulmonary, and renal diseases. Our purpose was to review the wide spectrum of pathologies related to blunt chest trauma involving the chest wall, pleura, lungs, trachea and bronchi, aorta, aortic arch vessels, and diaphragm. A particular focus on the diagnostic impact of CT is demonstrated. (orig.)

  8. High-field magnetization and ESR in the triangular-lattice antiferromagnets Ba{sub 3}MnSb{sub 2}O{sub 9} and Ba{sub 3}TNb{sub 2}O{sub 9} (T=Ni, Co)

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Y.C. [Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074 (China); School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China); Ouyang, Z.W., E-mail: zwouyang@mail.hust.edu.cn [Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074 (China); Ruan, M.Y.; Guo, Y.M.; Cheng, J.J. [Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074 (China); School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China); Tian, Z.M. [School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China); Xia, Z.C. [Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074 (China); Rao, G.H. [School of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004 (China)

    2015-11-01

    We report high-field magnetization and electronic spin resonance (ESR) study on the triangular-lattice antiferromagnets Ba{sub 3}MnSb{sub 2}O{sub 9} and Ba{sub 3}TNb{sub 2}O{sub 9} (T=Ni, Co). The antiferromagnetic (AFM) ordering at T{sub N} is clearly characterized by the temperature dependent ESR spectra. In Ba{sub 3}CoNb{sub 2}O{sub 9}, the complicated ESR peaks are observed above T{sub N}. No obvious frequency–field relationship could be deduced. In Ba{sub 3}NiNb{sub 2}O{sub 9}, the AFM resonance with easy-plane anisotropy is observed, and accordingly, the magnetic exchange interactions are estimated. For Ba{sub 3}MnSb{sub 2}O{sub 9}, the remarkable finding is that single resonance peak at paramagnetic state splits into double peaks below the ordering temperature. Possible interpretations for these unusual AFM resonance modes have been proposed. - Highlights: • In Ba{sub 3}NiNb{sub 2}O{sub 9}, anisotropy is observed, exchange interactions are estimated. • In Ba{sub 3}MnSb{sub 2}O{sub 9}, single resonance peaksplits into double peaks below T{sub N}. • Complicated ESR spectra have been observed in Ba{sub 3}CoNb{sub 2}O{sub 9} above T{sub N}.

  9. T1 and susceptibility contrast at high fields

    Science.gov (United States)

    Neelavalli, Jaladhar

    Clinical imaging at high magnetic field strengths (≥ 3Tesla) is sought after primarily due to the increased signal strength available at these fields. This increased SNR can be used to perform: (a) high resolution imaging in the same time as at lower field strengths; (b) the same resolution imaging with much faster acquisition; and (c) functional MR imaging (fMRI), dynamic perfusion and diffusion imaging with increased sensitivity. However they are also associated with increased power deposition (SAR) due to increase in imaging frequency and longer T1 relaxation times. Longer T1s mean longer imaging times for generating good T1 contrast images. On the other hand for faster imaging, at high fields fast spin echo or magnetization prepared sequences are conventionally proposed which are, however, associated with high SAR values. Imaging with low SAR is more and more important as we move towards high fields and particularly for patients with metallic implants like pacemakers or deep brain stimulator. The SAR limit acceptable for these patients is much less than the limit acceptable for normal subjects. A new method is proposed for imaging at high fields with good contrast with simultaneous reduction in power deposition. Further, T1 based contrast optimization problem in FLASH imaging is considered for tissues with different T1s but same spin densities. The solution providing optimal imaging parameters is simplified for quick and easy computation in a clinical setting. The efficacy of the simplification is evaluated and practical limits under which the simplification can be applied are worked out. The phase difference due to variation in magnetic susceptibility property among biological tissues is another unique source of contrast which is different from the conventional T1, T2 and T2* contrast. This susceptibility based phase contrast has become more and more important at high fields, partly due to contrast generation issues due to longer T 1s and shorter T2s and

  10. Chest Wall tumor: combined management

    International Nuclear Information System (INIS)

    Cancer is relatively rare disease among children and adolescents. The incidence of solid tumors other than CNS is less than 2/100,000. Tumors of the chest wall can arise either from the somatic tissue or ribs. These are rare, so either institutional reviews or multi institutional studies should determine optimal therapeutic management. Of the bony chest wall, Ewing's sarcoma or the family of tumor (peripheral neuro epithelioma, Askin tumor), are the most common. These lesions are lytic and have associated large extra pleural component. This large extra pleural component often necessitates major chest wall resection (3 or more ribs), and when lower ribs are involved, this entails resection of portion of diaphragm. Despite this resection, survival in the early 1970 was 10-20%. Since 1970 multi agent chemotherapy has increased survival rates. of importance, however, is these regimens have caused significant reduction of these extra pleural components so that major chest wall resections have become a rarity. With improved survival and decreased morbidity preoperative chemotherapy followed by surgery is now the accepted modality of treatment. Another major advantage of this regimen is that potential radiation therapy may be obviated. The most common chest wall lesion is rhabdomyosarcoma. In the IRS study of 1620 RMS patients, in 141 (9%) the primary lesion was in the chest wall. these are primarily alveolar histology. when lesions were superficial, wide local excision with supplemental radiation therapy was associated with low morbidity and good overall survival. however, a majority have significant intra- thoracic components. in these circumstances the resectability rate is less than 30% and the survival poor. Other lesions include non rhabdomyosarcomas, eosinophilic granuloma, chondrosarcoma, and osteomyelitis. The management of these lesions varies according to extent, histology, and patient characteristics

  11. Ultra-High Field MRI: Transition to Human 7 T in Finland - Workshop Memorandum

    OpenAIRE

    Auranen, Toni; Carlson, Synnöve; Hämäläinen, Matti; Jousmäki, Veikko; Renvall, Ville; Salmelin, Riitta

    2016-01-01

    A workshop “Ultra-High Field MRI: Transition to Human 7 T in Finland” was organized at Aalto University on October 8–9, 2015. The organizers included Aalto University School of Science, Finnish Infrastructures for Functional Imaging (FIFI), Aalto NeuroImaging (ANI), Aalto Brain Centre (ABC), and Department of Neuroscience and Biomedical Engineering (NBE). The purpose of the workshop was to demonstrate scientific achievements and possibilities enabled by ultra-high field (UHF) magnetic resonan...

  12. Contemporary management of flail chest.

    Science.gov (United States)

    Vana, P Geoff; Neubauer, Daniel C; Luchette, Fred A

    2014-06-01

    Thoracic injury is currently the second leading cause of trauma-related death and rib fractures are the most common of these injuries. Flail chest, as defined by fracture of three or more ribs in two or more places, continues to be a clinically challenging problem. The underlying pulmonary contusion with subsequent inflammatory reaction and right-to-left shunting leading to hypoxia continues to result in high mortality for these patients. Surgical stabilization of the fractured ribs remains controversial. We review the history of management for flail chest alone and when combined with pulmonary contusion. Finally, we propose an algorithm for nonoperative and surgical management. PMID:24887787

  13. Contemporary management of flail chest.

    Science.gov (United States)

    Vana, P Geoff; Neubauer, Daniel C; Luchette, Fred A

    2014-06-01

    Thoracic injury is currently the second leading cause of trauma-related death and rib fractures are the most common of these injuries. Flail chest, as defined by fracture of three or more ribs in two or more places, continues to be a clinically challenging problem. The underlying pulmonary contusion with subsequent inflammatory reaction and right-to-left shunting leading to hypoxia continues to result in high mortality for these patients. Surgical stabilization of the fractured ribs remains controversial. We review the history of management for flail chest alone and when combined with pulmonary contusion. Finally, we propose an algorithm for nonoperative and surgical management.

  14. Gunshot wounds to the chest

    OpenAIRE

    Holmen, Lillian Beate

    2013-01-01

    Introduction: This is a review of gunshot wounds to the chest. Although uncommon in Norway, they represent a big health problem in other parts of the world and in war situations. Method: A systematic literature search using PubMed and McMaster+. Results: Gunshot wounds to the chest can be highly lethal. Depending on the injured organ, a large percentage of the patients die before reaching the hospital. There is a big difference between low-velocity and high-velocity weapons. Low velocity inju...

  15. Accuracy of chest radiography versus chest computed tomography in hemodynamically stable patients with blunt chest trauma

    Institute of Scientific and Technical Information of China (English)

    Mojtaba Chardoli; Toktam Hasan-Ghaliaee; Hesam Akbari; Vafa Rahimi-Movaghar

    2013-01-01

    Objective:Thoracic injuries are responsible for 25% of deaths of blunt traumas.Chest X-ray (CXR) is the first diagnostic method in patients with blunt trauma.The aim of this study was to detect the accuracy of CXR versus chest computed tomograpgy (CT) in hemodynamically stable patients with blunt chest trauma.Methods:Study was conducted at the emergency department of S ina Hospital from March 2011 to March 2012.Hemodynamically stable patients with at least 16 years of age who had blunt chest trauma were included.All patients underwent the same diagnostic protocol which consisted of physical examination,CXR and CT scan respectively.Results:Two hundreds patients (84% male and 16% female) were included with a mean age of(37.9±13.7) years.Rib fracture was the most common finding of CXR (12.5%) and CT scan (25.5%).The sensitivity of CXR for hemothorax,thoracolumbar vertebra fractures and rib fractures were 20%,49% and 49%,respectively.Pneumothorax,foreign body,emphysema,pulmonary contusion,liver hematoma and sternum fracture were not diagnosed with CXR alone.Conclusion:Applying CT scan as the first-line diagnostic modality in hemodynamically stable patients with blunt chest trauma can detect pathologies which may change management and outcome.

  16. Ultra-high field magnetic resonance imaging of breast cancer

    NARCIS (Netherlands)

    Stehouwer, B.L.

    2014-01-01

    Dynamic contrast-enhanced (DCE) breast MRI plays an important role in the detection and staging of breast cancer. It has a high sensitivity of approximately 0.90 for the detection breast cancer, although the specificity of 0.72 is relatively low. Therefore, research has focused on improving specific

  17. An Atypical Cause of Atypical Chest Pain

    Directory of Open Access Journals (Sweden)

    Ahmad Zaheen

    2014-01-01

    Full Text Available The present report describes a case involving a 57-year-old HIV-positive man who presented with acute retrosternal chest pain accompanied by 24 h of fever. Septic arthritis of the manubriosternal joint was diagnosed based on magnetic resonance imaging findings in addition to Staphylococcus aureus bacteremia. To the authors’ knowledge, the present case is only the 12th reported case of manubriosternal septic arthritis, and the first in an HIV-positive patient. Early diagnosis and treatment can circumvent the need for surgical intervention. Based on the present case report and review of the literature, the authors summarize the epidemiology, appropriate imaging and suggestions for antibiotic therapy for this rare presentation.

  18. Actinomycosis involving the chest wall: CT findings

    International Nuclear Information System (INIS)

    Two cases of pulmonary actinomycosis with extension to involve the chest wall that were evaluated using computerized tomography are reported. In both cases, the relation of pulmonary and chest wall disease was best shown using CT

  19. Direct imaging of rf waveguide modes via ultra-high field NMR

    CERN Document Server

    Tonyushkin, A; Van de Moortele, P -F; Adriany, G; Kiruluta, A

    2016-01-01

    We demonstrate an experimental method for direct 2D and 3D imaging of magnetic rf field distribution in metal waveguides based on traveling wave (TW) nuclear-magnetic resonance (NMR) imaging at ultra-high field (>7T). The typical apparatus would include an ultra-high field whole body or small bore NMR scanner, waveguide elements filled with NMR active dielectrics with predefined electric and magnetic properties, and TW rf transmit-receive probes. We validated the technique by obtaining TW magnetic-resonance (MR) images of the magnetic field distribution of the rf modes of circular waveguide filled with deionized water in a 16.4 T small-bore NMR scanner and compared the MR images with numerical simulations. Our NMR technique opens up a practical way of imaging of previously inaccessible rf field distribution of modes inside of various shapes metal waveguides with inserted dielectric objects, including waveguide mode converters and transformers.

  20. Tritium system for compact high field devices

    International Nuclear Information System (INIS)

    Some theoretical results and the current status of the work on a prototype plant for the Tritium cycle of compact high-field tokamaks (such as, Ignitor, CIT, etc.), using the SAES Getter St 707 getter material, are described in this report. The schematics and present status of the main subplants of the cycle are reported together with some experimental results demostrating the possibility of utilizing the St 707 material to purify the inert atmosphere of the glove-boxes and the secondary containment of the double-containment metal canalization which is to eventually house the various parts of the plant. Finally, as an example, the FTU machine, under construction at ENEA Frascati, has been taken as a reference, and theoretical evaluations are given for the inventory, permeation and release of the Tritium from the first wall and the thermal shieldes of such a tokamak

  1. REVIEW OF HIGH FIELD Q SLOPE, CAVITY MEASUREMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Gianluigi Ciovati

    2008-01-23

    One of the most interesting phenomenon occurring in superconducting radio-frequency (SRF) cavities made of bulk niobium is represented by a sharp decrease of the quality factor above peak surface magnetic field of about 90 mT and is referred to as "high field Q-slope" or "Q-drop". This phenomenon was observed first in 1997 and since then some effort was devoted to the understanding of the causes behind it. Still, no clear physical interpretation of the Q-drop has emerged, despite several attempts. In this contribution, I will review the experimental results for various cavities measured in many laboratories and I will try to identify common features and differences related to the Q-drop.

  2. MRI of knee joint: first results of a comparison of a 0.2 T dedicated system with a 1.5 T high field strength magnet; MRT des Kniegelenks: Erste Ergebnisse eines Vergleichs von 0,2-T-Spezialsystem mit 1,5-T-Hochfeldmagnet

    Energy Technology Data Exchange (ETDEWEB)

    Kersting-Sommerhoff, B. [Inst. fuer Roentgendiagnostik, Klinikum der TU Muenchen (Germany); Gerhardt, P. [Inst. fuer Roentgendiagnostik, Klinikum der TU Muenchen (Germany); Golder, W. [Inst. fuer Roentgendiagnostik, Klinikum der TU Muenchen (Germany); Hof, N. [Inst. fuer Roentgendiagnostik, Klinikum der TU Muenchen (Germany); Riel, K.A. [Abt. fuer Sporttraumatologie, Orthopaedische Klinik, Klinikum der Technischen Univ. Muenchen (Germany); Helmberger, H. [Inst. fuer Roentgendiagnostik, Klinikum der TU Muenchen (Germany); Lenz, M. [Inst. fuer Roentgendiagnostik, Klinikum der TU Muenchen (Germany); Lehner, K. [Inst. fuer Roentgendiagnostik, Klinikum der TU Muenchen (Germany)

    1995-05-01

    Diagnostic accuracy and image quality of a specialised system for MR examinations of peripheral joints were evaluated. 20 patients with acute or chronic injuries of the knee were examined using a low-field MR system (0.2 T). For comparison, all patients were also studied with a 1.5 T high field strength magnet and all diagnoses were correlated with arthroscopic findings. We found compatible diagnostic accuracies (cruciate ligaments 90%, menisci 75-90%) and good image quality ratings for the low field system (`good` and `excellent` image quality in 83% of cases). (orig./MR) [Deutsch] Ein Spezialsystem zur MR-Diagnostik von peripheren Gelenkerkrankungen wurde auf diagnostische Treffsicherheit und Bildqualitaet untersucht. 20 Patienten mit akuten oder chronischen Kniegelenkslaesionen wurden in einem Niederfeld-Spezialsystem (0,2 T) sowie vergleichend in einem Hochfeldgeraet (1,5 T) kernspintomographisch untersucht. Alle Befunde wurden arthroskopisch ueberprueft. Es fanden sich vergleichbare diagnostische Trefsicherheiten (Kreuzbandlaesionen 90%, Meniskuslaesionen 75-90%) sowie eine gute Bildqualitaet (83% der Studien wurden als `gut` oder `sehr gut` beurteilt) des Niederfeldgeraetes. (orig./MG)

  3. Nuclear imaging of the chest

    Energy Technology Data Exchange (ETDEWEB)

    Bahk, Y.W. [Samsung Cheil General Hospital, Seoul (Korea, Republic of). Dept. of Radiology; Kim, E.E. [Texas Univ., Houston, TX (United States). Cancer Center; Isawa, T. [Yokohama Higashi National Hospital (Japan)

    1998-01-01

    This book provides up-to-the minute information on the diagnostic nuclear imaging of chest disorders. The authors have endeavored to integrate and consolidate the many different subspecialities in order to enable a holistic understanding of chest diseases from the nuclear medicine standpoint. Highlights of the book include in addition to the cardiac scan the description of aerosol lung imaging in COPD and other important pulmonary diseases and the updates on breast and lung cancer imaging, as well as imaging of the bony thorax and esophagus. It is required reading not only for nuclear medicine practitioners and researchers but also for all interested radiologists, traumatologists, pulmonologists, oncologists and cardiologists. (orig.) 217 figs., 25 tabs.

  4. Actinomycosis - Left Post Chest Wall

    Directory of Open Access Journals (Sweden)

    Kafil Akhtar, M. Naim, S. Shamshad Ahmad, Nazoora Khan, Uroos Abedi, A.H. Khan*

    2008-01-01

    Full Text Available A forty year old female of weak body built presented with recurring small hard lumps in let posteriorchest wall for 3 years and discharging ulcers for 3 months duration. Clinically, the provisional diagnosiswas malignancy with secondary infection. FNAC showed features suggestive of dysplasia buthistopathology confirmed the diagnosis as actinomycosis. The present case is reported due to rare incidenceof actinomycosis at post chest wall with muscle involvement.

  5. Chest wall, lung, and pleural space trauma.

    Science.gov (United States)

    Miller, Lisa A

    2006-03-01

    Chest radiographs frequently underestimate the severity and extent of chest trauma and, in some cases, fail to detect the presence of injury. CT is more sensitive than chest radiography in the detection of pulmonary, pleural, and osseous abnormalities in the patient who has chest trauma. With the advent of multidetector CT (MDCT), high-quality multiplanar reformations are obtained easily and add to the diagnostic capabilities of MDCT. This article reviews the radiographic and CT findings of chest wall, pleural, and pulmonary injuries that are seen in the patient who has experienced blunt thoracic trauma.

  6. Chest shape in preterm newborn infants

    International Nuclear Information System (INIS)

    The suggestion that thoracic shape of anteroposterior radiographs reflects lung compliance was examined in 62 preterm newborn infants (none with pulmonary hypoplasia) by measuring ratios of upper to lower chest widths. Chest shape did not vary significantly with the presence of respiratory distress syndrome (RDS) or with gender, Apgar score, endotracheal intubation, radiographic severity of RDS, or age at radiography. However, decreased maturity was associated with a relatively wide upper chest and narrow lower chest. Developmental factors may be more important than lung compliance (and the other factors noted) in determining the radiographic configuration of the infantile chest

  7. Gastric tumors on chest radiographs

    International Nuclear Information System (INIS)

    Gastric neoplasms of three patients protruded into their gas-containing fornices and were first visualized on plain chest radiographs. Endoscopy and/or surgery confirmed these to be a polyp, a leiomyoma, and an adenocarcinoma. The polyp, 1.3 cm in diameter, was the smallest of these three, but smaller lesions may be detectable under suitable conditions. Adequate technique and positioning, sufficiently large lesions in the upper portion of the stomach, a central beam tangential to the tumor, sufficient gas in the stomach, and careful scrutiny by the observer are required. Lesions may be more readily visualized during chest radiography when oral sodium bicarbonate is used to distend the stomach. In chest radiography, exposure limited to the lung fields has been advocated for economy and dose reduction. However, too small an exposure field may result in loss of information potentially beneficial to the patient. Using the smaller of two popular film sizes (35 x 43 cm and 35 x 35 cm), the saving in surface and bone marrow doses is negligible, and the saving in gonad dose may be nil over that when shielding is used. The interest of the observer may be absorbed by a concomitant cardiac or pulmonary lesion. Careful scrutiny of the entire radiograph is therefore essential. (author)

  8. Studies on the reliability of high-field intra-operative MRI in brain glioma resection

    Directory of Open Access Journals (Sweden)

    Zhi-jun SONG

    2011-07-01

    Full Text Available Objective To evaluate the reliability of high-field intra-operative magnetic resonance imaging(iMRI in detecting the residual tumors during glioma resection.Method One hundred and thirty-one cases of brain glioma(69 males and 62 females,aged from 7 to 79 years with mean of 39.6 years hospitalized from Nov.2009 to Aug.2010 were involved in present study.All the patients were evaluated using magnetic resonance imaging(MRI before the operation.The tumors were resected under conventional navigation microscope,and the high-field iMRI was used for all the patients when the operators considered the tumor was satisfactorily resected,while the residual tumor was difficult to detect under the microscope,but resected after being revealed by high-field iMRI.Histopathological examination was performed.The patients without residual tumors recieved high-field MRI scan at day 4 or 5 after operation to evaluate the accuracy of high-field iMRI during operation.Results High quality intra-operative images were obtained by using high-field iMRI.Twenty-eight cases were excluded because their residual tumors were not resected due to their location too close to functional area.Combined with the results of intra-operative histopathological examination and post-operative MRI at the early recovery stage,the sensitivity of high-field iMRI in residual tumor diagnosis was 98.0%(49/50,the specificity was 94.3%(50/53,and the accuracy was 96.1%(99/103.Conclusion High-quality intra-operative imaging could be acquired by high-field iMRI,which maybe used as a safe and reliable method in detecting the residual tumors during glioma resection.

  9. High-Field Phenomena of Qubits

    OpenAIRE

    van Tol, Johan; Morley, G. W.; Takahashi, S.; McCamey, D. R.; Boehme, C.; Zvanut, M. E.

    2009-01-01

    Electron and nuclear spins are very promising candidates to serve as quantum bits (qubits) for proposed quantum computers, as the spin degrees of freedom are relatively isolated from their surroundings and can be coherently manipulated, e.g., through pulsed electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR). For solid-state spin systems, impurities in crystals based on carbon and silicon in various forms have been suggested as qubits, and very long relaxation rates hav...

  10. 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.

  11. High-Field Phenomena of Qubits.

    Science.gov (United States)

    van Tol, Johan; Morley, G W; Takahashi, S; McCamey, D R; Boehme, C; Zvanut, M E

    2009-12-01

    Electron and nuclear spins are very promising candidates to serve as quantum bits (qubits) for proposed quantum computers, as the spin degrees of freedom are relatively isolated from their surroundings and can be coherently manipulated, e.g., through pulsed electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR). For solid-state spin systems, impurities in crystals based on carbon and silicon in various forms have been suggested as qubits, and very long relaxation rates have been observed in such systems. We have investigated a variety of these systems at high magnetic fields in our multifrequency pulsed EPR/ENDOR (electron nuclear double resonance) spectrometer. A high magnetic field leads to large electron spin polarizations at helium temperatures, giving rise to various phenomena that are of interest with respect to quantum computing. For example, it allows the initialization of both the electron spin as well as hyperfine-coupled nuclear spins in a well-defined state by combining millimeter and radio-frequency radiation. It can increase the T(2) relaxation times by eliminating decoherence due to dipolar interaction and lead to new mechanisms for the coherent electrical readout of electron spins. We will show some examples of these and other effects in Si:P, SiC:N and nitrogen-related centers in diamond. PMID:19946596

  12. U.S. EPA High-Field NMR Facility with Remote Accessibility

    Science.gov (United States)

    EPA’s High-Field Nuclear Magnetic Resonance Research Facility housed in Athens, GA has two Varian 600 MHz NMR spectrometers used for conducting sophisticated experiments in environmental science. Off-site users can ship their samples and perform their NMR experiments remotely fr...

  13. Lumbar Modic Changes - A Comparison Between Findings at Low-and High-field MRI

    DEFF Research Database (Denmark)

    Bendix, Tom; Sorensen, Joan S; Henriksson, Gustaf A C;

    2012-01-01

    Study Design. A cross-sectional observational study.Objective. To investigate if there is a difference in findings of lumbar Modic changes in low-field (0.3 Tesla) magnetic resonance imaging (MRI) as compared to high field (1.5 Tesla).Summary of Background Data. It is a challenge to give patients...

  14. The design of a large aperture high field dipole

    Energy Technology Data Exchange (ETDEWEB)

    Harfoush, F.; Harrison, M.; Kerby, J.; Koepke, K.; Mantsch, P.; Nicol, T.; Riddiford, A.; Theilacker, J.

    1989-12-01

    The impetus for this design report originated in the Snowmass 88 meeting where the subject of higher energies within the constraints of the existing Tevatron tunnel enclosure was investigated. It was determined that beam transport to the fixed target experimental areas was possible up to an energy of {approximately}1.5 Tev. Collider operation was feasible at somewhat higher energies (1.8 Tev), primarily limited by the ability to design a single turn beam abort system within the constraints of the straight section length. A new accelerator in the existing tunnel would, of necessity, have a similar though not identical lattice and straight section layout to the present Tevatron. Thus when issues arose in the magnet design requiring input from the accelerator standpoint we have assumed a Tevatron like machine. The possibility of using these high field magnets as elements in the existing Tevatron to create new warm space,' for another Interaction Region for example, also emphasizes compatibility with the present machine. 16 refs., 62 figs., 23 tabs.

  15. High field optical nonlinearities in gases

    Science.gov (United States)

    Cheng, Yu-Hsiang

    Optical femtosecond self-channeling in gases, also called femtosecond filamentation, has become an important area of research in high field nonlinear optics. Filamentation occurs when laser light self-focuses in a gas owing to self-induced nonlinearity, and then defocuses in the plasma generated by the self-focused beam. The result of this process repeating itself multiple times is an extended region of plasma formation. Filamentation studies have been motivated by the extremely broad range of applications, especially in air, including pulse compression, supercontinuum generation, broadband high power terahertz pulse generation, discharge triggering and guiding, and remote sensing. Despite the worldwide work in filamentation, the fundamental gas nonlinearities governing self-focusing had never been directly measured in the range of laser intensity up to and including the ionization threshold. This dissertation presents the first such measurements. We absolutely measured the temporal refractive index change of O2, N2, Ar, H2, D2 and N2O caused by highfield ultrashort optical pulses with single-shot supercontinuum spectral interferometry, cleanly separating for the first time the instantaneous electronic and delayed rotational nonlinear response in diatomic gases. We conclusively showed that a recent claim by several European groups that the optical bound electron nonlinearity saturates and goes negative is not correct. Such a phenomenon would preclude the need for plasma to provide the defocusing contribution for filamentation. Our results show that the 'standard model of filamentation', where the defocusing is provided by plasma, is correct. Finally, we demonstrated that high repetition rate femtosecond laser pulses filamenting in gases can generate long-lived gas density `holes' which persist on millisecond timescales, long after the plasma has recombined. Gas density decrements up to ~20% have been measured. The density hole refilling is dominated by thermal

  16. Threats to ultra-high-field MRI

    Science.gov (United States)

    Le Bihan, Denis

    2009-08-01

    In 2004 the European Commission (EC) adopted a directive restricting occupational exposure to electromagnetic fields. This directive (2004/40/CE), which examines the possible health risks of the electromagnetic fields from mobile phones, Wi-Fi, Bluetooth and other devices, concluded that upper limits on radiation and applied electromagnetic fields are necessary to prevent workers from suffering any undue acute health effects. But although not initially intended, the biggest impact of the directive could be on magnetic resonance imaging (MRI), which is used in hospitals worldwide to produce images of unrivalled quality of the brain and other soft tissues.

  17. Imaging of fetal chest masses

    Energy Technology Data Exchange (ETDEWEB)

    Barth, Richard A. [Lucile Packard Children' s Hospital, Stanford University School of Medicine, Department of Radiology, Stanford, CA (United States)

    2012-01-15

    Prenatal imaging with high-resolution US and rapid acquisition MRI plays a key role in the accurate diagnosis of congenital chest masses. Imaging has enhanced our understanding of the natural history of fetal lung masses, allowing for accurate prediction of outcome, parental counseling, and planning of pregnancy and newborn management. This paper will focus on congenital bronchopulmonary malformations, which account for the vast majority of primary lung masses in the fetus. In addition, anomalies that mimic masses and less common causes of lung masses will be discussed. (orig.)

  18. Chest neoplasms with infectious etiologies.

    Science.gov (United States)

    Restrepo, Carlos S; Chen, Melissa M; Martinez-Jimenez, Santiago; Carrillo, Jorge; Restrepo, Catalina

    2011-12-28

    A wide spectrum of thoracic tumors have known or suspected viral etiologies. Oncogenic viruses can be classified by the type of genomic material they contain. Neoplastic conditions found to have viral etiologies include post-transplant lymphoproliferative disease, lymphoid granulomatosis, Kaposi's sarcoma, Castleman's disease, recurrent respiratory papillomatosis, lung cancer, malignant mesothelioma, leukemia and lymphomas. Viruses involved in these conditions include Epstein-Barr virus, human herpes virus 8, human papillomavirus, Simian virus 40, human immunodeficiency virus, and Human T-lymphotropic virus. Imaging findings, epidemiology and mechanism of transmission for these diseases are reviewed in detail to gain a more thorough appreciation of disease pathophysiology for the chest radiologist.

  19. Potential of ultrasound in the pediatric chest

    Energy Technology Data Exchange (ETDEWEB)

    Trinavarat, Panruethai, E-mail: pantrinavarat@hotmail.com [Department of Radiology, Faculty of Medicine, Chulalongkorn University, Rama IV Road, Pathumwan, Bangkok 10330 (Thailand); Riccabona, Michael, E-mail: michael.riccabona@klinikum-graz.at [Department of Radiology, Division of Pediatric Radiology, University Hospital Graz (Austria)

    2014-09-15

    Ultrasound (US) of chest, even with inherent limitations of the US beam and air, has been useful in many pediatric chest conditions. It has extended its role and is now widely used by many subspecialists in medicine. This review article will cover techniques, indications, and applications of chest US in neonates, infants and children, including also different common as well as some rare and modern aspects and applications, such as pleural effusion, pneumothorax, pulmonary lesions, mediastinum, diaphragm, and chest wall. Other related imaging modalities are also briefly discussed.

  20. Alternative Approach to the Provision of the High-field Dipole for FCC-hh

    CERN Document Server

    AUTHOR|(SzGeCERN)435046

    2015-01-01

    This paper describes a possible approach to reducing the complexity and cost of the high field dipole magnets. In addition the cooling of the winding could be improved in the proposed design, with a consequent reduction in the shielding requirements. The correction of multipoles is also addressed: this feature may impact on the dynamic range of operation of the magnets. Noting that it would be possible to add a small gradient component to the dipole, it is suggested that a (partially) combined function lattice should be considered. The proposals lead to a brief re-appraisal of how best to apply superconductivity to magnets for large accelerators.

  1. Anteroposterior chest radiograph vs. chest CT scan in early detection of pneumothorax in trauma patients

    OpenAIRE

    Omar, Hesham R.; Mangar, Devanand; Khetarpal, Suneel; Shapiro, David H; Kolla, Jaya; Rashad, Rania; Helal, Engy; Camporesi, Enrico M

    2011-01-01

    Pneumothorax is a common complication following blunt chest wall trauma. In these patients, because of the restrictions regarding immobilization of the cervical spine, Anteroposterior (AP) chest radiograph is usually the most feasible initial study which is not as sensitive as the erect chest X-ray or CT chest for detection of a pneumothorax. We will present 3 case reports which serve for better understanding of the entity of occult pneumothorax. The first case is an example of a true occult ...

  2. High field superconductors for superconducting machines

    International Nuclear Information System (INIS)

    By the solid state diffusion process high current capacity Nb3Sn multifilament conductors were fabricated with filament numbers up to 70 000 and filament diameters down to 1,5 μm and with effective current densities up to 8.6 x 104 A/cm2 at 10 T and 4.2 K. Conductors without additional stabilization as well as monolithic conductors with external or internal copper stabilization and with tantalum diffusion barriers are being developed. Moreover, calibrated flattened cables of twisted strands were fabricated for higher currents (up to 1000 A at 10 T). Generally quantitative relations could be given for the rise of the critical current of Nb3Sn multifilament conductors observed under the influence of mechanical stresses. Long lengths (km) of these conductors were used to manufacture superconducting solenoids by two different ways. These reached the short sample current usually without training and delivered magnetic flux densities up to 14 T with an 8.5 T NbTi background field. (orig.)

  3. 3.0T高场强核磁共振设备机房布局及施工准备%Research on the layout and construction preparation for 3.0T high-field nuclear magnetic resonance equipment room

    Institute of Scientific and Technical Information of China (English)

    孙继江; 何晓彬; 步岩生

    2013-01-01

    目的:通过对3.0T核磁共振设备机房施工前期的合理布局、充分准备,缩短了施工时间,使得后期使用安全便捷,为医院节约了资金。方法:根据医院具体特点,在选址时充分考虑运输、配电、通风、承重及电磁干扰等问题,逐步进行落实、做好施工准备。结果:机房选址要求承重在10t以上、磁体中心点3 m内铁磁物质要做评估,周围移动的汽车及变压器必须在3G线以外,要求有专用变压器且容量>150 kVA。设备接地电阻<2Ω,屏蔽房对地绝缘>1000Ω。失超管高出地面3.8 m以上,周围不能有空调进风口。水冷机通风良好,北方地区还要做好室外机的冬季防冻。磁体间排风按每小时换气≥12次设计。结论:医院大型设备施工准备及辅助设备安装过程中的各个环节要匹配合理,同时注重和不同单位之间的协作。合理的设备布局和施工准备,是设备顺利安装的保证。%Objective:To do the research on the layout and construction preparation for 3.0T high-field nuclear magnetic resonance equipment room, greatly shorten the construction time and save money for hospital by the safe and convenient usage. Methods: According to the specific characteristics of hospital sitting in full consideration of transportation and distribution, ventilation, bearing, electromagnetic interference and so on, we implement gradually, were ready to work in the construction. Results: Computer room location requirements bearing within 10 tons, magnets, center of 3 m in ferromagnetic material to do assessment, and moving around the car and the transformer must be beyond 3G line, required a special transformer and the capacity of more than 150 kVA. Equipment grounding resistance is less than 2 ohms, shielding room of insulation is greater than 1000 ohms. Super tube is higher than 3.8 m above the ground, there be no air conditioning air inlet. Water-cooled machine well

  4. The value of conventional high-field MRI in MS in the light of the McDonald criteria: a literature review

    DEFF Research Database (Denmark)

    Larsen, Line Sofie Lunde; Larsson, H B W; Frederiksen, Jette Lautrup Battistini

    2010-01-01

    The diagnosis of MS is based on the revised McDonald criteria and is multidisciplinary. Both clinical and paraclinical measures are included. High-field magnetic resonance imaging (MRI) is becoming increasingly available and it is therefore necessary to clarify possible advantages of high-field MRI...... of lesions to be better at high field. Of the seven studies, six found more and bigger lesions at high-field MRI. In the present paper, the relevant MRI sequences are evaluated in detail. The detection of more lesions at high-field strength did not seem to lead to earlier diagnosis of clinically definite...

  5. General Atomic's superconducting high field test facility and initial performance

    International Nuclear Information System (INIS)

    General Atomic has established a high field test facility whose primary mission is to investigate the J-B-T and stability performance margins of commercial NbTi superconductor in the 10 tesla, 4.20K region. This work is part of the overall DOE/MFE/MAGNETIC SYSTEMS effort to provide an adequate technological base for construction of superconducting toroidal field coils for the next generation of large tokamak fusion devices. The principal components of the facility are the coil/cryostat assembly, the helium refrigerator-liquefier/compressor system, and the gaseous helium recovery and storage system. The epoxy impregnated, layer wound main background field coil generates 8 tesla within its 40 cm diameter bore. The insert background field coil was layer wound with cooling channels provided by ''barber pole'' mylar conductor insulation. Ten tesla is generated within its 22 cm bore. The initial performance of the facility will be discussed. Future testing calls for operating test coils with implanted heating elements to simulate mechanically induced perturbations. The normal zone growth and recovery behavior will be observed for various disturbance energies. This data will then be compared with results obtained from the transient recovery analysis developed at General Atomic

  6. Remote interpretation of chest roentgenograms.

    Science.gov (United States)

    Andrus, W S; Hunter, C H; Bird, K T

    1975-04-01

    A series of 98 chest films was interpreted by two physicians on the basis of monitor display of the transmitted television signal representing the roentgenographic image. The transmission path was 14 miles long, and included one active repeater station. Receiver operating characteristic curves were drawn to compare interpretations rendered on television view of the image with classic, direct view interpretations of the same films. Performance in these two viewing modes was found to be quite similar. When films containing only hazy densities lacking internal structure or sharp margins, were removed from the sample, interpretation of the remaining films was essentially identical via the two modes. Since hazy densities are visible on retrospective examination, interpretation of roentgenograms at a distance via television appears to be a feasible route for delivery of radiologic services.

  7. Chest pain in focal musculoskeletal disorders

    DEFF Research Database (Denmark)

    Stochkendahl, Mette Jensen; Christensen, Henrik Wulff

    2010-01-01

    The musculoskeletal system is a recognized source of chest pain. However, despite the apparently benign origin, patients with musculoskeletal chest pain remain under-diagnosed, untreated, and potentially continuously disabled in terms of anxiety, depression, and activities of daily living. Several...

  8. Chest pain and exacerbations of bronchiectasis

    Directory of Open Access Journals (Sweden)

    King PT

    2012-12-01

    Full Text Available Paul T King,1,2 Stephen R Holdsworth,2 Michael Farmer,1 Nicholas J Freezer,1 Peter W Holmes11Department of Respiratory and Sleep Medicine, 2Monash University Department of Medicine, Monash Medical Centre, Melbourne, Victoria, AustraliaBackground: Bronchiectasis is a common disease and a major cause of respiratory morbidity. Chest pain has been described as occurring in the context of bronchiectasis but has not been well characterized. This study was performed to describe the characteristics of chest pain in adult bronchiectasis and to define the relationship of this pain to exacerbations.Subjects and methods: We performed a prospective study of 178 patients who were followed-up for 8 years. Subjects were reviewed on a yearly basis and assessed for the presence of chest pain. Subjects who had chest pain at the time of clinical review by the investigators were included in this study. Forty-four patients (25% described respiratory chest pain at the time of assessment; in the majority of cases 39/44 (89%, this occurred with an exacerbation and two distinct types of chest pain could be described: pleuritic (n = 4 and non-pleuritic (n = 37, with two subjects describing both forms. The non-pleuritic chest pain occurred most commonly over both lower lobes and was mild to moderate in severity. The pain subsided as patients recovered. Conclusion: Non-pleuritic chest pain occurs in subjects with bronchiectasis generally in association with exacerbations.Keywords: sputum, collapse, bronchitis, airway obstruction

  9. Solitary Plasmacytoma of the Chest Wall

    Directory of Open Access Journals (Sweden)

    Servet Kayhan

    2014-03-01

    Full Text Available A previously healthy 55-year-old man with right sided lateral chest pain admitted to clinic. It was found a solid and painful mass at the right 4th rib in physical examination. Chest X-ray and thoracic computarized tomography showed an opacity measured 60x33 mm within the right chest wall destructing the 4th rib. Needle aspiration was performed from tumor and cytologic examination showed atypic plasma cell infiltration. The patient was scheduled for a chest wall resection and reconstructive surgery. Examination of a permanent section showed that the chest wall tumor was solitary plasmacytoma. There was no evidence of multiple myeloma recurrence after two years from the operation.

  10. High-Field Wave Packets in Semiconductor Quantum Wells: A Real-Space Finite-Difference Time-Domain Formalism

    OpenAIRE

    Hughes, S

    2004-01-01

    An untraditional space-time method for describing the dynamics of high-field electron-hole wave packets in semiconductor quantum wells is presented. A finite-difference time-domain technique is found to be computationally efficient and can incorporate Coulomb, static, terahertz, and magnetic fields to all orders, and thus can be applied to study many areas of high-field semiconductor physics. Several electro-optical and electro-magneto-optical excitation schemes are studied, some well known a...

  11. Radiological imaging of the neonatal chest. 2. rev. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Donoghue, Veronica (ed.) [Children' s University Hospital, Dublin (Ireland). Dept. of Radiology; National Maternity Hospital, Dublin (Ireland)

    2008-07-01

    This second, revised edition of Radiological Imaging of the Neonatal Chest provides a comprehensive and up-to-date discussion of the subject. It is written primarily from the point of view of the paediatric radiologist but will be of particular interest to all antenatal ultrasonographers, neonatologists, paediatric cardiologists, paediatricians and paediatric surgeons. It includes an update on clinical management and appraises the advantages of the various techniques available to image the newborn chest. There is particular emphasis on the impact of recent therapeutic advances on imaging findings. Extensive consideration is given to both antenatal and postnatal imaging of congenital chest malformations, as well as to controversies regarding the postnatal management of asymptomatic infants with these anomalies. There are dedicated chapters on upper airway problems, infection and congenital heart disease, with special emphasis on the current role of magnetic resonance imaging, computed tomography and interventional therapy. There is also a chapter devoted to computed radiography and digital radiography. This book contains important information for all those involved in caring for the neonate. (orig.)

  12. USE OF SUPERCONDUCTING MAGNETS IN MAGNETIC SEPARATION

    OpenAIRE

    Parker, M.

    1984-01-01

    A review is given assessing the potential for superconducting high-field magnet systems in magnetic separation. Particular attention is given to the advantages of the reciprocating canister approach to high gradient magnetic separation and to the use of quadrupole magnets in open gradient magnetic separation.

  13. CT of blunt chest trauma in children

    International Nuclear Information System (INIS)

    While trauma is still the leading cause of death in the pediatric age range, it is surprising how little the CT appearances of pediatric chest injury have been investigated in the literature. We have reviewed the CT findings of blunt chest trauma in 44 children for whom chest CT examinations were requested to investigate the extent of intrathoracic injury. We noted a propensity for pulmonary contusions to be located posteriorly or posteromedially, and for them to be anatomically nonsegmental and crescentic in shape. This is possibly attributable to the relatively compliant anterior chest wall in children. The CT appearances of other major thoracic injuries are described, including pulmonary lacerations, pneumothoraces, malpositioned chest tubes, mediastinal hematomas, aortic injury, tracheobronchial injury, hemopericardium, and spinal injuries with paraspinal fluid collections. Children demonstrating findings incidental to the actual injury yet important to the subsequent therapy are also presented. We conclude that, in the event of clinically significant blunt chest trauma, the single supine chest examination in the trauma room is insufficient to adequately identify the extent of intrathoracic injury. With the exception of concern for aortic injury for which aortography is indicated, a dynamically enhanced CT scan of the thorax should be performed as clinically significant findings may result in altered therapy. (orig.)

  14. Integration of ultra-high field MRI and histology for connectome based research of brain disorders

    OpenAIRE

    Shan Yang; Zhengyi Yang; Karin Fischer; Kai Zhong; Christian Mawrin; David Reutens; Oliver Speck; Martin Walter

    2013-01-01

    Ultra-high field magnetic resonance imaging (MRI) became increasingly relevant for in vivo neuroscientific research because of improved spatial resolutions. However, this is still the unchallenged domain of histological studies, which long played an important role in the investigation of neuropsychiatric disorders. While the field of biological psychiatry strongly advanced on macroscopic levels, current developments are rediscovering the richness of immunohistological information when attempt...

  15. Chest CT in children: anesthesia and atelectasis

    Energy Technology Data Exchange (ETDEWEB)

    Newman, Beverley; Gawande, Rakhee [Lucile Packard Children' s Hospital, Department of Radiology, Stanford, CA (United States); Krane, Elliot J. [Stanford University School of Medicine, Lucile Packard Children' s Hospital, Department of Anesthesiology, Perioperative and Pain Medicine, Stanford, CA (United States); Holmes, Tyson H. [Stanford University School of Medicine, Lucile Packard Children' s Hospital, Department of Psychiatry and Behavioral Sciences, Stanford, CA (United States); Robinson, Terry E. [Stanford University School of Medicine, Lucile Packard Children' s Hospital, Department of Pulmonary Medicine and Cystic Fibrosis Center for Excellence in Pulmonary Biology, Stanford, CA (United States)

    2014-02-15

    There has been an increasing tendency for anesthesiologists to be responsible for providing sedation or anesthesia during chest CT imaging in young children. Anesthesia-related atelectasis noted on chest CT imaging has proven to be a common and troublesome problem, affecting image quality and diagnostic sensitivity. To evaluate the safety and effectiveness of a standardized anesthesia, lung recruitment, controlled-ventilation technique developed at our institution to prevent atelectasis for chest CT imaging in young children. Fifty-six chest CT scans were obtained in 42 children using a research-based intubation, lung recruitment and controlled-ventilation CT scanning protocol. These studies were compared with 70 non-protocolized chest CT scans under anesthesia taken from 18 of the same children, who were tested at different times, without the specific lung recruitment and controlled-ventilation technique. Two radiology readers scored all inspiratory chest CT scans for overall CT quality and atelectasis. Detailed cardiorespiratory parameters were evaluated at baseline, and during recruitment and inspiratory imaging on 21 controlled-ventilation cases and 8 control cases. Significant differences were noted between groups for both quality and atelectasis scores with optimal scoring demonstrated in the controlled-ventilation cases where 70% were rated very good to excellent quality scans compared with only 24% of non-protocol cases. There was no or minimal atelectasis in 48% of the controlled ventilation cases compared to 51% of non-protocol cases with segmental, multisegmental or lobar atelectasis present. No significant difference in cardiorespiratory parameters was found between controlled ventilation and other chest CT cases and no procedure-related adverse events occurred. Controlled-ventilation infant CT scanning under general anesthesia, utilizing intubation and recruitment maneuvers followed by chest CT scans, appears to be a safe and effective method to obtain

  16. Chest CT in children: anesthesia and atelectasis

    International Nuclear Information System (INIS)

    There has been an increasing tendency for anesthesiologists to be responsible for providing sedation or anesthesia during chest CT imaging in young children. Anesthesia-related atelectasis noted on chest CT imaging has proven to be a common and troublesome problem, affecting image quality and diagnostic sensitivity. To evaluate the safety and effectiveness of a standardized anesthesia, lung recruitment, controlled-ventilation technique developed at our institution to prevent atelectasis for chest CT imaging in young children. Fifty-six chest CT scans were obtained in 42 children using a research-based intubation, lung recruitment and controlled-ventilation CT scanning protocol. These studies were compared with 70 non-protocolized chest CT scans under anesthesia taken from 18 of the same children, who were tested at different times, without the specific lung recruitment and controlled-ventilation technique. Two radiology readers scored all inspiratory chest CT scans for overall CT quality and atelectasis. Detailed cardiorespiratory parameters were evaluated at baseline, and during recruitment and inspiratory imaging on 21 controlled-ventilation cases and 8 control cases. Significant differences were noted between groups for both quality and atelectasis scores with optimal scoring demonstrated in the controlled-ventilation cases where 70% were rated very good to excellent quality scans compared with only 24% of non-protocol cases. There was no or minimal atelectasis in 48% of the controlled ventilation cases compared to 51% of non-protocol cases with segmental, multisegmental or lobar atelectasis present. No significant difference in cardiorespiratory parameters was found between controlled ventilation and other chest CT cases and no procedure-related adverse events occurred. Controlled-ventilation infant CT scanning under general anesthesia, utilizing intubation and recruitment maneuvers followed by chest CT scans, appears to be a safe and effective method to obtain

  17. Classification of chest wall diseases.

    Science.gov (United States)

    Pozzi, E; Gulotta, C

    1993-01-01

    Several disorders of the thoracic cage are known to cause respiratory failure, by means of relatively simple mechanisms, such as the increased work of breathing, which results in alveolar hypoventilation. A variety of pathogenic mechanisms may be considered, as functions of the types of thoracic disorders present. As causes of these additional potential mechanisms, we considered the following: 1) ventilation-perfusion (V/Q) inhomogeneity; 2) inability to cough; 3) malformation or acquired defect of the respiratory centres; and 4) excess blood volume and fluid retention, which aggravate work of breathing and V/Q inhomogeneity. All of these disorders can be grouped into two major categories (which nevertheless have some of the pathophysiology in common): the mechanical syndrome and the neuromuscular or paralytic syndrome. In this paper we discuss chest wall diseases falling into the first category; namely, kyphoscoliosis, fibrothorax, thoracoplasty, ankylosing spondylitis and obesity-hypoventilation. Congenital deformities of the thoracic cage, which do not have important effects on ventilatory apparatus (e.g. pectus excavatum and pectus carinatum), were also considered. PMID:8472068

  18. Impacts to the chest of PMHSs - Influence of impact location and load distribution on chest response.

    Science.gov (United States)

    Holmqvist, Kristian; Svensson, Mats Y; Davidsson, Johan; Gutsche, Andreas; Tomasch, Ernst; Darok, Mario; Ravnik, Dean

    2016-02-01

    The chest response of the human body has been studied for several load conditions, but is not well known in the case of steering wheel rim-to-chest impact in heavy goods vehicle frontal collisions. The aim of this study was to determine the response of the human chest in a set of simulated steering wheel impacts. PMHS tests were carried out and analysed. The steering wheel load pattern was represented by a rigid pendulum with a straight bar-shaped front. A crash test dummy chest calibration pendulum was utilised for comparison. In this study, a set of rigid bar impacts were directed at various heights of the chest, spanning approximately 120mm around the fourth intercostal space. The impact energy was set below a level estimated to cause rib fracture. The analysed results consist of responses, evaluated with respect to differences in the impacting shape and impact heights on compression and viscous criteria chest injury responses. The results showed that the bar impacts consistently produced lesser scaled chest compressions than the hub; the Middle bar responses were around 90% of the hub responses. A superior bar impact provided lesser chest compression; the average response was 86% of the Middle bar response. For inferior bar impacts, the chest compression response was 116% of the chest compression in the middle. The damping properties of the chest caused the compression to decrease in the high speed bar impacts to 88% of that in low speed impacts. From the analysis it could be concluded that the bar impact shape provides lower chest criteria responses compared to the hub. Further, the bar responses are dependent on the impact location of the chest. Inertial and viscous effects of the upper body affect the responses. The results can be used to assess the responses of human substitutes such as anthropomorphic test devices and finite element human body models, which will benefit the development process of heavy goods vehicle safety systems. PMID:26687541

  19. Technique for chest radiography for pneumoconiosis

    International Nuclear Information System (INIS)

    Routine radiographic chest examinations have been performed using a variety of techniques. Although chest radiography is one of the most commonly performed radiographic examinations, it is often difficult to obtain consistently good quality roentgenograms. This publication provides a simple guide and relatively easy solution to the many problems that radiologic technologists might encounter. The language is purposely relatively simple and care has been taken to avoid difficult mathematical and physical explanations. The intent is to provide an easily referrable text for those who may encounter difficulties in producing acceptable chest radiographs

  20. Chest pain: a time for concern?

    Science.gov (United States)

    King, Joan E; Magdic, Kathy S

    2014-01-01

    When a patient complains of chest pain, the first priority is to establish whether the situation is life threatening. Life-threatening differential diagnoses that clinicians must consider include acute coronary syndrome, cardiac tamponade, pulmonary embolus, aortic dissection, and tension pneumothorax. Nonthreatening causes of chest pain that should be considered include spontaneous pneumothorax, pleural effusion, pneumonia, valvular diseases, gastric reflux, and costochondritis. The challenge for clinicians is not to be limited by "satisfaction of search" and fail to consider important differential diagnoses. The challenge, however, can be met by developing a systematic method to assess chest pain that will lead to the appropriate diagnosis and appropriate treatment plan.

  1. High-field 3He-F interaction at the surface of fluorocarbon spheres

    DEFF Research Database (Denmark)

    Schuhl, A.; Chapellier, M.; Rasmussen, Finn Berg

    1984-01-01

    High-field experiments on the relaxation betweenF in small Teflon spheres andHe on the surface are reported. WithHe as a monolayer, coupling times are found to be less than 5 sec, in magnetic fields up to 3 T and temperatures down to 50 mK, where electronic centers are completely polarized....... The results between 200 and 300 mK and for three magnetic fields fit a coupling model involving an unusually large exchange interaction in the monolayer. With liquidHe we obtain a linear dependence of theHe relaxation time upon both field and temperature. © 1984 Plenum Publishing Corporation....

  2. Common Acupoints in Chest and Abdomen

    Institute of Scientific and Technical Information of China (English)

    Journal of Acupuncture and Tuina Science Editor; CUI Xue-jun

    2003-01-01

    @@ Tiantu (CV 21) Location: In the center of the suprasternal fossa(Fig. l ). Indications: Cough, dyspnea, chest pain, pharyngolaryngeal swelling and pains, sudden hoarseness of the voice, goiter, globus hystericus, and dysphagia.

  3. Tuberculosis, advanced - chest x-rays (image)

    Science.gov (United States)

    Tuberculosis is an infectious disease that causes inflammation, the formation of tubercules and other growths within tissue, ... death. These chest x-rays show advanced pulmonary tuberculosis. There are multiple light areas (opacities) of varying ...

  4. Aspergillosis - chest x-ray (image)

    Science.gov (United States)

    ... usually occurs in immunocompromised individuals. Here, a chest x-ray shows that the fungus has invaded the lung ... are usually seen as black areas on an x-ray. The cloudiness on the left side of this ...

  5. Angina - when you have chest pain

    Science.gov (United States)

    ... or having sex. How to treat your chest pain Sit, stay calm, and rest. Your symptoms will often go away soon after you stop activity. If you are lying down, sit up in bed. Try deep breathing to ...

  6. Open-Chest Management after Heart Transplantation

    OpenAIRE

    Takayama, Hiroo; Leone, Richard J.; Aldea, Gabriel S.; Fishbein, Daniel P.; Verrier, Edward D.; Salerno, Christopher T.

    2006-01-01

    Postcardiotomy open-chest management has been widely used in cardiac surgery. Although this strategy can be applied to heart transplantation, the use of immunosuppressants in transplant recipients raises particular concerns about sternal wound infection and impaired healing.

  7. [Dedifferentiated Chondrosarcoma of the Chest Wall].

    Science.gov (United States)

    Saitoh, Genkichi; Yoneshima, Yasuto; Nakamura, Toshihiko; Kitagawa, Dai; Kinjo, Nao; Ohgaki, Kippei; Maehara, Shinichiro; Teramoto, Seiichi; Adachi, Eisuke; Ikeda, Yoichi; Mine, Mari

    2016-08-01

    A 79-year-old man complaining of an anterior chest mass with pain had an abnormal shadow on chest X-ray. A mass, 7 cm in size, with destruction of the right 4th rib was found on chest computed tomography. A F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) corresponding to the lesion showed an abnormal accumulation of FDG with the standardized uptake value(SUV) max=16.19. A malignant tumor of the chest wall origin was suspected and the tumor was resected with the 3th, 4th, and 5th ribs. Histologically, the tumor was diagnosed as dedifferentiated chondrosarcoma. He died of local recurrence about 5 months after the operation. PMID:27476566

  8. Surface Chest Motion Decomposition for Cardiovascular Monitoring

    OpenAIRE

    Ghufran Shafiq; Kalyana C. Veluvolu

    2014-01-01

    Surface chest motion can be easily monitored with a wide variety of sensors such as pressure belts, fiber Bragg gratings and inertial sensors, etc. The current applications of these sensors are mainly restricted to respiratory motion monitoring/analysis due to the technical challenges involved in separation of the cardiac motion from the dominant respiratory motion. The contribution of heart to the surface chest motion is relatively very small as compared to the respiratory motion. Further, t...

  9. Misdiagnosed Chest Pain: Spontaneous Esophageal Rupture

    OpenAIRE

    Inci, Sinan; Gundogdu, Fuat; Gungor, Hasan; Arslan, Sakir; Turkyilmaz, Atila; Eroglu, Atila

    2013-01-01

    Chest pain is one of themost common complaints expressed by patients presenting to the emergency department, and any initial evaluation should always consider life-threatening causes. Esophageal rupture is a serious condition with a highmortality rate. If diagnosed, successful therapy depends on the size of the rupture and the time elapsed between rupture and diagnosis.We report on a 41-year-old woman who presented to the emergency department complaining of left-sided chest pain for two hours.

  10. DT and DHe3 tokamak test reactor concepts using advanced, high field superconductors

    International Nuclear Information System (INIS)

    If practical high temperature superconducting ceramic magnets can be developed, there could be a significant impact on reactor design. Potential advantages include a simpler, more robust magnet design, the possibility of demountable superconducting toroidal field coils and reduced shielding requirements. The high temperature superconductors can also have very high critical fields and could provide super high field operation. This could substantially increase eta tau/sub E/ values, reduce β requirements, and improve prospects for ohmic heating to ignition. The combination of moderately high β and super high field could make DHe3 operation possible in a JET size tokamak. In this paper we discuss possibilities for test reactor designs using high temperature high field superconductors. An illustrative design has a field at the plasma of 15 T. This reduces the required β to less than 2% for DT operation. The required plasma current is 5 MA. For a reactor size of R0 = 3.4m and a = 0.6m, the neutron wall loading is 3.3 MW/m2 at β = 1.5% for DT operation and an equal amount of fusion power is produced at β = 10% for DHe3 operation. One possible mode of operation is to use ohmic heating to ignition in a DT plasma followed by thermal runaway to DHe3 temperatures. 7 refs., 1 fig., 2 tabs

  11. Radiographic, CT and MRI spectrum of hydatid disease of the chest: a pictorial essay

    Energy Technology Data Exchange (ETDEWEB)

    Sinner, W.N. von [Dept. of Radiology MBC28, King Faisal Specialist Hospital and Research Centre, Riyadh (Saudi Arabia)

    1993-01-01

    Thirty patients with thoracic hydatidosis (Echinococcus granulosus) were studied. The hydatid cysts were located in the lung parenchyma (70%), mediastinum (6.7%), inside the heart (10%), the pleurae (10%) and the chest wall (3.3%). Complications of thoracic hydatid cysts, such as rupture, infection, pleural involvement, spread and calcifications are presented. Computed tomography (CT) without and/or with contrast enhancement was performed in all patients (30). Findings from conventional chest radiographs were compared with CT and confirmed by pathology (30). In 10 cases (33.3%), magnetic resonance imaging was also performed. The diagnostic spectrum of hydatid cysts, including variations and developmental stages, is presented in this pictorial essay. (orig.)

  12. Radiographic, CT and MRI spectrum of hydatid disease of the chest: a pictorial essay

    International Nuclear Information System (INIS)

    Thirty patients with thoracic hydatidosis (Echinococcus granulosus) were studied. The hydatid cysts were located in the lung parenchyma (70%), mediastinum (6.7%), inside the heart (10%), the pleurae (10%) and the chest wall (3.3%). Complications of thoracic hydatid cysts, such as rupture, infection, pleural involvement, spread and calcifications are presented. Computed tomography (CT) without and/or with contrast enhancement was performed in all patients (30). Findings from conventional chest radiographs were compared with CT and confirmed by pathology (30). In 10 cases (33.3%), magnetic resonance imaging was also performed. The diagnostic spectrum of hydatid cysts, including variations and developmental stages, is presented in this pictorial essay. (orig.)

  13. Pediatric chest imaging. Chest imaging in infants and children. 2. rev. ed.

    International Nuclear Information System (INIS)

    Imaging of the pediatric chest continues to evolve rapidly. All chapters in this 2nd edition of Pediatric Chest Imaging have been extensively updated, with additional disease-specific information and numerous new illustrations. The book thus presents the state of the art in the diagnosis of pediatric chest disorders, highlighting the role played by advanced technology. As the conventional features of most of these disorders are extremely well known, special attention is devoted to the technical aspects of the modern imaging modalities, their indications, and the diagnostic information that they supply. Individual chapters focus on chest ultrasound, nuclear medicine imaging, high-resolution chest CT, helical CT, and pediatric cardiac CT and pediatric cardiacMRI. Others are directed towards specific disorders, including congenital malformations of the chest, chest tumors, pulmonary infection, trauma, the lung in systemic diseases, the pediatric airway, foreign bodies, the thymus, and the chest wall. Without exception, the authors of this book are internationally known specialists with great expertise in the field. This book will serve as a handy, superbly illustrated reference for all who routinely image children, as well as for those who need access to information on how best to image them. (orig.)

  14. Evaluation of pneumonia in children: comparison of MRI with fast imaging sequences at 1.5T with chest radiographs

    International Nuclear Information System (INIS)

    Background Although there has been a study aimed at magnetic resonance imaging (MRI) evaluation of pneumonia in children at a low magnetic field (0.2T), there is no study which assessed the efficacy of MRI, particularly with fast imaging sequences at 1.5T, for evaluating pneumonia in children. Purpose To investigate the efficacy of chest MRI with fast imaging sequences at 1.5T for evaluating pneumonia in children by comparing MRI findings with those of chest radiographs. Material and Methods This was an Institutional Review Board-approved, HIPPA-compliant prospective study of 40 consecutive pediatric patients (24 boys, 16 girls; mean age 7.3 years ± 6.6 years) with pneumonia, who underwent PA and lateral chest radiographs followed by MRI within 24 h. All MRI studies were obtained in axial and coronal planes with two different fast imaging sequences: T1-weighted FFE (Fast Field Echo) (TR/TE: 83/4.6) and T2-weighted B-FFE M2D (Balanced Fast Field Echo Multiple 2D Dimensional) (TR/TE: 3.2/1.6). Two experienced pediatric radiologists reviewed each chest radiograph and MRI for the presence of consolidation, necrosis/abscess, bronchiectasis, and pleural effusion. Chest radiograph and MRI findings were compared with Kappa statistics. Results All consolidation, lung necrosis/abscess, bronchiectasis, and pleural effusion detected with chest radiographs were also detected with MRI. There was statistically substantial agreement between chest radiographs and MRI in detecting consolidation (k = 0.78) and bronchiectasis (k = 0.72) in children with pneumonia. The agreement between chest radiographs and MRI was moderate for detecting necrosis/abscess (k = 0.49) and fair for detecting pleural effusion (k = 0.30). Conclusion MRI with fast imaging sequences is comparable to chest radiographs for evaluating underlying pulmonary consolidation, bronchiectasis, necrosis/abscess, and pleural effusion often associated with pneumonia in children

  15. Evaluation of pneumonia in children: comparison of MRI with fast imaging sequences at 1.5T with chest radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Yikilmaz, Ali; Koc, Ali; Coskun, Abdulhakim (Dept. of Radiology, Erciyes Medical School, Kayseri (Turkey)); Ozturk, Mustafa K (Dept. of Pediatric Infectious Diseases, Erciyes Medical School, Kayseri (Turkey)); Mulkern, Robert V; Lee, Edward Y (Dept. of Radiology and Dept. of Medicine, Pulmonary Div., Children' s Hospital Boston and Harvard Medical School, Boston (United States)), email: Edward.lee@childrens.harvard.edu

    2011-10-15

    Background Although there has been a study aimed at magnetic resonance imaging (MRI) evaluation of pneumonia in children at a low magnetic field (0.2T), there is no study which assessed the efficacy of MRI, particularly with fast imaging sequences at 1.5T, for evaluating pneumonia in children. Purpose To investigate the efficacy of chest MRI with fast imaging sequences at 1.5T for evaluating pneumonia in children by comparing MRI findings with those of chest radiographs. Material and Methods This was an Institutional Review Board-approved, HIPPA-compliant prospective study of 40 consecutive pediatric patients (24 boys, 16 girls; mean age 7.3 years +- 6.6 years) with pneumonia, who underwent PA and lateral chest radiographs followed by MRI within 24 h. All MRI studies were obtained in axial and coronal planes with two different fast imaging sequences: T1-weighted FFE (Fast Field Echo) (TR/TE: 83/4.6) and T2-weighted B-FFE M2D (Balanced Fast Field Echo Multiple 2D Dimensional) (TR/TE: 3.2/1.6). Two experienced pediatric radiologists reviewed each chest radiograph and MRI for the presence of consolidation, necrosis/abscess, bronchiectasis, and pleural effusion. Chest radiograph and MRI findings were compared with Kappa statistics. Results All consolidation, lung necrosis/abscess, bronchiectasis, and pleural effusion detected with chest radiographs were also detected with MRI. There was statistically substantial agreement between chest radiographs and MRI in detecting consolidation (k = 0.78) and bronchiectasis (k = 0.72) in children with pneumonia. The agreement between chest radiographs and MRI was moderate for detecting necrosis/abscess (k = 0.49) and fair for detecting pleural effusion (k = 0.30). Conclusion MRI with fast imaging sequences is comparable to chest radiographs for evaluating underlying pulmonary consolidation, bronchiectasis, necrosis/abscess, and pleural effusion often associated with pneumonia in children

  16. Chest trauma in children: A local experience

    International Nuclear Information System (INIS)

    Chest trauma in childhood is relatively uncommon in clinical practice andhas been the subject of few reports in literature. This study was undertakento examine our experience in dealing with chest trauma in children. This wasa retrospective study of 74 children who sustained chest trauma and werereferred to King Fahd Hospital in Medina over a two-year period. The age,cause of injury, severity of injury, associated extrathoracic injuries,treatment and outcome were analyzed. The median age of patients was nineyears. Fifty-nine of them (80%) sustained blunt trauma in 62% of thechildren, gun shot wounds were seen in five and stab wounds in 10 children.Head injury was the most common injury associated with thoracic trauma andwas seen in 14 patients (19%) and associated intra-abdominal injuries wereseen in nine patients. Chest x-ray of the blunt trauma patients revealedfractured ribs in 24 children, pneumothorax in six, hemothorax in four,hemoneumothorax in three, and pulmonary contusions in 22 patients. Fifty onepercent of children were managed conservatively, 37% required tubethoracostomy, 8% were mechanically ventilated and 4% underwent thoractomy.The prevalence of chest trauma in children due to road traffic accidents ishigh in Saudi Arabia. Head injury is thought to be the most common associatedextrathoracic injuries, however, most of these patients can be managedconservatively. (author)

  17. Radiation induced osteosarcoma of the chest wall

    Energy Technology Data Exchange (ETDEWEB)

    Sugimoto, Tsutomu; Yuki, Yoshihiro; Oizumi, Hiroyuki; Iijima, Yoshiyuki; Fujishima, Tsukasa; Shimazaki, Yasuhisa [Yamagata Univ. (Japan). School of Medicine

    1996-11-01

    We report a successful resection of an osteosarcoma in the chest wall developed 25 years after irradiation. A 74-year-old woman was admitted to our hospital for her swelling in the left chest wall at August 24, 1995. At 49-year-old, she had undergone an operation and postoperative irradiation for left breast cancer. A computed tomography demonstrated a mass in the left chest wall that destructed the first rib, extending into the pleural space and invaded into the left common carotid and subclavian arteries. We planned a radical resection of the mass after repeated CT scannings, since it was histopathologically diagnosed as a chondrosarcoma and showed a rapid growth. The tumor was completely removed with radical transmediastinal forequarter amputation of the partial chest wall and total left upper extremity. The left common carotid artery was partially replaced with 6 mm EPTFE vascular prosthesis. The chest wall was reconstructed with Marlex-mesh prosthesis and a myocutaneous flap. She was discharged uneventfully and has not shown any evidence of recurrence. (author)

  18. Heat treatment study of $Nb_{3}Sn$ strands for the Fermilab's high field dipole model

    CERN Document Server

    Barzi, E; Limon, P J; Ozelis, J P; Yamada, R; Zlobin, A V; Gregory, E; Pyon, T; Wake, M

    2000-01-01

    Fermilab is developing high field superconducting dipole magnets based on Nb/sub 3/Sn for a post-LHC very large hadron collider (VLHC) . The first prototype is a 1 meter long two-layer shell-type (cos- theta) coil with a nominal field of 11 T. A keystoned Rutherford-type cable made of 28 Nb/sub 3/Sn strands of 1 mm in diameter is used. The development of high J/sub c/ multifilamentary Nb/sub 3/Sn strands with low magnetization is an important step of this program. To achieve this goal, strand R&D is actively pursued by Fermilab and IGC using the internal tin process. Conductor designs, heat treatment studies, and results of measurements, including I/sub c/, n-value, RRR, magnetization, and chemical analyses, are presented. (4 refs).

  19. Cardiogenic shock following blunt chest trauma

    Directory of Open Access Journals (Sweden)

    Rodríguez-González Fayna

    2010-01-01

    Full Text Available Cardiac contusion, usually caused by blunt chest trauma, has been recognized with increased frequency over the past decades. Traffic accidents are the most frequent cause of cardiac contusions resulting from a direct blow to the chest. Other causes of blunt cardiac injury are numerous and include violent fall impacts, interpersonal aggression, explosions, and various types of high-risk sports. Myocardial contusion is difficult to diagnose; clinical presentation varies greatly, ranging from lack of symptoms to cardiogenic shock and arrhythmia. Although death is rare, cardiac contusion can be fatal. We present a case of cardiac contusion due to blunt chest trauma secondary to a fall impact, which manifested as cardiogenic shock.

  20. Misdiagnosed Chest Pain: Spontaneous Esophageal Rupture

    Science.gov (United States)

    Inci, Sinan; Gundogdu, Fuat; Gungor, Hasan; Arslan, Sakir; Turkyilmaz, Atila; Eroglu, Atila

    2013-01-01

    Chest pain is one of themost common complaints expressed by patients presenting to the emergency department, and any initial evaluation should always consider life-threatening causes. Esophageal rupture is a serious condition with a highmortality rate. If diagnosed, successful therapy depends on the size of the rupture and the time elapsed between rupture and diagnosis.We report on a 41-year-old woman who presented to the emergency department complaining of left-sided chest pain for two hours. PMID:27122690

  1. ADX: a high field, high power density, Advanced Divertor test eXperiment

    Science.gov (United States)

    Vieira, R.; Labombard, B.; Marmar, E.; Irby, J.; Shiraiwa, S.; Terry, J.; Wallace, G.; Whyte, D. G.; Wolfe, S.; Wukitch, S.; ADX Team

    2014-10-01

    The MIT PSFC and collaborators are proposing an advanced divertor experiment (ADX) - a tokamak specifically designed to address critical gaps in the world fusion research program on the pathway to FNSF/DEMO. This high field (6.5 tesla, 1.5 MA), high power density (P/S ~ 1.5 MW/m2) facility would utilize Alcator magnet technology to test innovative divertor concepts for next-step DT fusion devices (FNSF, DEMO) at reactor-level boundary plasma pressures and parallel heat flux densities while producing high performance core plasma conditions. The experimental platform would also test advanced lower hybrid current drive (LHCD) and ion-cyclotron range of frequency (ICRF) actuators and wave physics at the plasma densities and magnetic field strengths of a DEMO, with the unique ability to deploy launcher structures both on the low-magnetic-field side and the high-field side - a location where energetic plasma-material interactions can be controlled and wave physics is most favorable for efficient current drive, heating and flow drive. This innovative experiment would perform plasma science and technology R&D necessary to inform the conceptual development and accelerate the readiness-for-deployment of FNSF/DEMO - in a timely manner, on a cost-effective research platform. Supported by DE-FC02-99ER54512.

  2. 7.0T功能MR波谱动态定量检测视觉皮层代谢物对视觉刺激的反应%Investigation of the metabolic changes in visual cortex due to visual stimulation using high field magnetic resonance spectroscopy at 7.0 T

    Institute of Scientific and Technical Information of China (English)

    林艳; Morris Peter; 吴仁华

    2012-01-01

    investigate the metabolic changes in the visual cortex due to visual stimulation using high field functional proton magnetic resonance spectroscopy at 7.0 T.A clear picture of brain metabolism and neurotransmitter activity during activation was expected to be established.Methods Nine healthy subjects participated in this study. All MR measurements were acquired using a 7.0 T MR system and a 16-channel SENSE head coil. An initial fMRI scan was performed prior to spectroscopic acquisition in order to determine the activated region in the visual cortex.A cubic ROI of 2 cm× 2 cm × 2 cm was positioned inside the activated region for functional MRS acquisition.A short TE STEAM sequence was used for acquiring the MRS data. The functional paradigm comprised 6.6 min baseline followed by 13.2 min of visual stimulation and 19.8 min recovery.Summed averaged spectra for visual stimulus off and visual stimulus on were analyzed separately using LC Model and internal reference of water. A Wilcoxon signed rank test was conducted to compare the metabolite changes. Results During stimulation,concentration in Asp [ ( 3.20 ± 0.28 ) μmol/g ],Gln [ ( 2.07 ± 0.10 ) μmol/g ] and Gly [ ( 1.65 ± 0.11 )μmol/g ] was found to be significantly decreased,compared with that of ( 3.52 ± 0.28 ),( 2.25 ± 0.10 ) and ( 1.85 ± 0.11 ) μmol/g in rest ( Z =- 2.073,- 2.073 and - 2.429,respectively,P < 0.05 ).The level in Glu [ ( 11.50 ± 0.11 ) μmol/g],GSH[ (2.45 ± 0.10) μmol/g] and Lac[ (0.89 ± 0.05) μ.mol/g]due to neuronal activation was found to be significantly increased,versus resting concentration of ( 11.28 ± 0.11 ),( 2.28 ± 0.10 ) and (0.79 ± 0.05 ) μmol/g,respectively ( Z =2.521,2.310,2.016,respectively,P <0.05).Glc level [ (1.54 ± 0.23 )μmol/g] exhibited a tendency to decrease throughout the period of stimulation,compared with that of [ (1.78 ± 0.28 ) μmol/g ] in rest,but the decrease did not reach statistical significance (Z =- 1.897,P > 0.05 ).Conclusions Using a novel visual

  3. Observation of Thermoelectric Currents in High-Field Superconductor-Ferromagnet Tunnel Junctions.

    Science.gov (United States)

    Kolenda, S; Wolf, M J; Beckmann, D

    2016-03-01

    We report on the experimental observation of spin-dependent thermoelectric currents in superconductor-ferromagnet tunnel junctions in high magnetic fields. The thermoelectric signals are due to a spin-dependent lifting of the particle-hole symmetry, and are found to be in excellent agreement with recent theoretical predictions. The maximum Seebeck coefficient inferred from the data is about -100  μV/K, much larger than commonly found in metallic structures. Our results directly prove the coupling of spin and heat transport in high-field superconductors.

  4. Observation of Thermoelectric Currents in High-Field Superconductor-Ferromagnet Tunnel Junctions

    Science.gov (United States)

    Kolenda, S.; Wolf, M. J.; Beckmann, D.

    2016-03-01

    We report on the experimental observation of spin-dependent thermoelectric currents in superconductor-ferromagnet tunnel junctions in high magnetic fields. The thermoelectric signals are due to a spin-dependent lifting of the particle-hole symmetry, and are found to be in excellent agreement with recent theoretical predictions. The maximum Seebeck coefficient inferred from the data is about -100 μ V /K , much larger than commonly found in metallic structures. Our results directly prove the coupling of spin and heat transport in high-field superconductors.

  5. High Field Seeking State Atom Laser and Properties of Flux

    Institute of Scientific and Technical Information of China (English)

    XIA Lin; XIONG Wei; YANG Fan; YI Lin; ZHOU Xiao-Ji; CHEN Xu-Zong

    2008-01-01

    We present an experimental study on the continuous atom laser. The experiments show that a high field seeking state atom laser with stable flux can be formed by increasing the strength of outcoupling before large density fluctuations appear. It is easy to obtain a long length or high speed output with this kind of atom laser.

  6. Chest trauma in childhood. Radiological findings

    International Nuclear Information System (INIS)

    Blunt thoracic trauma is frequently associated with further injuries (head and/or blunt abdominal trauma). The prognosis also depends on the concurrent injuries. The initial evaluation of an injured child is based on the chest X-ray and abdominal ultrasound examination. Additional information can be obtained by a CT scan in mediastinal injuries. (orig./MG)

  7. Coccidioidomycosis - chest x-ray (image)

    Science.gov (United States)

    This chest x-ray shows the affects of a fungal infection, coccidioidomycosis. In the middle of the left lung (seen on the ... defined borders. Other diseases that may explain these x-ray findings include lung abscesses, chronic pulmonary tuberculosis, chronic ...

  8. Adenocarcinoma - chest x-ray (image)

    Science.gov (United States)

    This chest x-ray shows adenocarcinoma of the lung. There is a rounded light spot in the right upper lung (left side ... density. Diseases that may cause this type of x-ray result would be tuberculous or fungal granuloma, and ...

  9. Chest Pain: Delays in seeking medical attention

    OpenAIRE

    Dickson, R.; Shuster, M; Brown, G B

    1992-01-01

    A multicenter prospective survey of 101 patients who presented to the emergency departments of five metropolitan medical centers complaining of non-traumatic chest pain showed that many delayed going to hospital. We call for more effective communication between physicians, patients, and the public and for improved public education on the signs and symptoms of myocardial infarction and the correct response.

  10. Treatment of 336 cases of chest trauma

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jing; CHU Xiang-yang; LIU Yi; WANG Yun-xi

    2012-01-01

    Objective: To summarize the clinical features,diagnosis and treatment of chest trauma.Methods: A retrospective analysis was conducted among 336 cases of chest trauma admitted to our hospital from January 2009 to May 2011.Results:Out of all cases,325 were cured,accounting for 96.7%; 11 died,accounting for 3.3%.Among the dead cases,one died of hemorrhagic shock,three of acute respiratory distress syndrome,three of multiple organ failure,and four of severe multiple traumas.Conclusions:(1) For patients with severe chest trauma,early emergency treatment is crucial to save life.(2) Open thoracic surgery is needed for acute cardiac tamponade,intrapulmonary vascular injuries,progressive intrathoracic bleeding,lung laceration,tracheal breakage,and diaphragmatic injury.In addition,operative timing and method should be well chosen.(3) Pulmonary contusion is one of common complications in chest trauma,for which the combination of strong anti-infection therapy and mechanical ventilation is an effective treatment strategy.

  11. The HEART score for chest pain patients

    NARCIS (Netherlands)

    Backus, B.E.

    2012-01-01

    The HEART score was developed to improve risk stratification in chest pain patients in the emergency department (ED). This thesis describes series of validation studies of the HEART score and sub studies for individual elements of the score. The predictive value of the HEART score for the occurrence

  12. VAC® for external fixation of flail chest

    DEFF Research Database (Denmark)

    Winge, Rikke; Berg, Jais O; Albret, Rikke;

    2012-01-01

    A large aterior chest wall defect following tumor resection was reconstructed with a Gore-Tex® membrane and a combined musculocutaneous rectus femoris and tensor fasciae latae free flap. Subsequent paradoxical respiration impeded weaning from the ventilator. Appliance of Vacuum Assisted Closure...

  13. Chest injury in victims of Bam earthquake

    Institute of Scientific and Technical Information of China (English)

    Seyed Mohammad Ghodsi; Moosa Zargar; Ali Khaji; Mojgan Karbakhsh

    2006-01-01

    Objective: To analyze the data of trauma patients with thoracic injury in the earthquake of Bam admitted to hospitals of Tehran University of Medical Science (TUMS)for better understanding the type and consequence of thoracic injuries in a major earthquake.Methods: After Bam earthquake registering 6.5 on the Richter scale, 526 trauma patients were admitted to hospitals of TUMS. Among them, 53 patients sustained thoracic injury.Results: This group was composed of 21 females (39.6%) and 32 males (60.4%). Fifteen patients (28.3%) had isolated chest injuries. Rib fracture (36.4%) was the most common injury in our patients and haemo/pneumothorax (25.5%) followed. Superficial injury was the most common accompanying injury. Multipletrauma patients with chest injury had higher injury severity score (ISS) versus patients with isolated chest injury (P =0.003).Conclusions: Chest wall injuries and haemo/pneumothorax comprise a considerable number of injuries in survival victims of earthquakes. Consequently, the majority of these patients can be treated with observation or tube thoracostomy. We should train and equip the health workers and members of rescue teams to treat and manage these patients in the field.

  14. Algorithm of chest wall keloid treatment.

    Science.gov (United States)

    Long, Xiao; Zhang, Mingzi; Wang, Yang; Zhao, Ru; Wang, Youbin; Wang, Xiaojun

    2016-08-01

    Keloids are common in the Asian population. Multiple or huge keloids can appear on the chest wall because of its tendency to develop acne, sebaceous cyst, etc. It is difficult to find an ideal treatment for keloids in this area due to the limit of local soft tissues and higher recurrence rate. This study aims at establishing an individualized protocol that could be easily applied according to the size and number of chest wall keloids.A total of 445 patients received various methods (4 protocols) of treatment in our department from September 2006 to September 2012 according to the size and number of their chest wall keloids. All of the patients received adjuvant radiotherapy in our hospital. Patient and Observer Scar Assessment Scale (POSAS) was used to assess the treatment effect by both doctors and patients. With mean follow-up time of 13 months (range: 6-18 months), 362 patients participated in the assessment of POSAS with doctors.Both the doctors and the patients themselves used POSAS to evaluate the treatment effect. The recurrence rate was 0.83%. There was an obvious significant difference (P keloids. This algorithm could play a guiding role for surgeons when dealing with chest wall keloid treatment. PMID:27583896

  15. Value of in vivo monitoring of abdominal aortic atherosclerosis by high field magnetic resonance imaging in apoE -/- mice fed a high fat diet or infused with angiotensin Ⅱ%小鼠腹主动脉斑块模型建立的两种方法及超高场强磁共振成像的应用价值

    Institute of Scientific and Technical Information of China (English)

    赵瑞; 姚玉宇; 邓钢; 居胜红; 王中娟; 文颂; 陈骏; 金晖

    2010-01-01

    差异有统计学意义(P=0.017),分别为(2.65±0.48)mm2和(1.21±0.21)mm2,部分小鼠可见夹层动脉瘤形成.AngⅡ500 ng·kg-1·min-1组灌注后斑块面积也比灌注前有所进展,面积分别为(1.01±0.17)mm2和(0.85±0.11)mm2,MRI测量的斑块面积与病理测量的斑块面积有较高的一致性(r值为0.93).结论 AngⅡ灌注显著加快动脉粥样硬化进展并促进腹主动脉夹层动脉瘤形成,长期高脂饮食亦可形成晚期斑块.超高场强MRI多种序列黑血技术的综合应用能显示小鼠腹主动脉粥样硬化斑块的进展,其检测分析斑块大小结果与病理表现基本一致,对斑块成分的判定亦有一定价值.%Objective To explore the value of in vivo dynamic monitoring of abdominal aortic atherosclerosis (AS) by high field magnetic resonance (MR) imaging (MRI) in apoE - / - mice fed a high fat diet or infused with angiotensin. Methods High fat diet or angiotensin Ⅱ infusion was applied to apoE-/- mice for establishment of abdominal aortic atherosclerosis model. Abdominal aorta MRI was performed at 3 time points (baseline, 3 and 6 months) in 13 high fat diet fed apoE -/- mice aged 10 -12months and 3 wild-type control mice; 10 apoE -/- mice aged 6 months were infused with angiotensin Ⅱaortic artery MRI was performed at baseline and 14 d after infusion. Black blood sequences of FLASH T1 weighted images and Proton density weighted -T2 weighted dual echo images were obtained. At each observation time post MRI, mice (n =3, 5 and 5 for high fat diet group and n =5 and 5 for angiotensin Ⅱinfusion group) were sacrificed for pathological examination of the abdominal artery. Results ( 1 ) The abdominal aorta atherosclerosis was identified in both high fat diet and angiotensin Ⅱ treated apoE -/-mice but in WT controls. Lesion progression was documented in high fat diet fed apoE -/- mice characterized by significantly increased vessel wall( a marker of atherosclerotic burden, F = 29. 94, P < 0. 05 )and gradually increased plaque

  16. Get Smart: Know When Antibiotics Work - Bronchitis (Chest Cold)

    Science.gov (United States)

    ... Farm Get Smart About Antibiotics Week Bronchitis (Chest Cold) Language: English Español (Spanish) Recommend on Facebook Tweet ... types—acute bronchitis. Causes Acute bronchitis, or chest cold, often occurs after an upper respiratory infection like ...

  17. CNE article: pain after lung transplant: high-frequency chest wall oscillation vs chest physiotherapy.

    Science.gov (United States)

    Esguerra-Gonzalez, Angeli; Ilagan-Honorio, Monina; Fraschilla, Stephanie; Kehoe, Priscilla; Lee, Ai Jin; Marcarian, Taline; Mayol-Ngo, Kristina; Miller, Pamela S; Onga, Jay; Rodman, Betty; Ross, David; Sommer, Susan; Takayanagi, Sumiko; Toyama, Joy; Villamor, Filma; Weigt, S Samuel; Gawlinski, Anna

    2013-03-01

    Background Chest physiotherapy and high-frequency chest wall oscillation (HFCWO) are routinely used after lung transplant to facilitate removal of secretions. To date, no studies have been done to investigate which therapy is more comfortable and preferred by lung transplant recipients. Patients who have less pain may mobilize secretions, heal, and recover faster. Objectives To compare effects of HFCWO versus chest physiotherapy on pain and preference in lung transplant recipients. Methods In a 2-group experimental, repeated-measures design, 45 lung transplant recipients (27 single lung, 18 bilateral) were randomized to chest physiotherapy (10 AM, 2 PM) followed by HFCWO (6 PM, 10 PM; group 1, n=22) or vice versa (group 2, n=23) on postoperative day 3. A verbal numeric rating scale was used to measure pain before and after treatment. At the end of the treatment sequence, a 4-item patient survey was administered to assess treatment preference, pain, and effectiveness. Data were analyzed with χ(2) and t tests and repeated-measures analysis of variance. Results A significant interaction was found between mean difference in pain scores from before to after treatment and treatment method; pain scores decreased more when HFCWO was done at 10 AM and 6 PM (P =.04). Bilateral transplant recipients showed a significant preference for HFCWO over chest physiotherapy (11 [85%] vs 2 [15%], P=.01). However, single lung recipients showed no significant difference in preference between the 2 treatments (11 [42%] vs 14 [54%]). Conclusions HFCWO seems to provide greater decreases in pain scores than does chest physiotherapy. Bilateral lung transplant recipients preferred HFCWO to chest physiotherapy. HFCWO may be an effective, feasible alternative to chest physiotherapy. (American Journal of Critical Care. 2013;22:115-125).

  18. Hyperfine coupling constant for {sup 59}Co estimated from a high-field susceptibility and high-field NMR shift in ferromagnetic Co{sub 2}TiGa and Co{sub 2}VGa

    Energy Technology Data Exchange (ETDEWEB)

    Nishihara, H; Furutani, Y; Wada, T [Faculty of Science and Technology, Ryukoku University, Otsu 520-2194 (Japan); Kanomata, T [Faculty of Engineering, Tohoku Gakuin University, Tagajo 985-8537 (Japan); Kobayashi, K; Ishida, K [Graduate School of Engineering, Tohoku University, Sendai 980-8579 (Japan); Kainuma, R [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Koyama, K; Watanabe, K, E-mail: nishihara@rins.ryukoku.ac.j [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)

    2010-01-01

    The hyperfine coupling constant for {sup 59}Co in the ferromagnetic state of a Heusler alloy Co{sub 2}TiGa in the high-field range has been estimated to be 170 kOe per 1 {mu}{sub B} of the moment of cobalt atom from the high-field magnetic susceptibility of 2.3 x 10{sup -6} emu/gOe measured at 5 K in a field range from 20 to 70 kOe and a reported positive high-field NMR shift of +0.83 percent. The value of the hyperfine coupling constant has been found to be even larger in the case of Co{sub 2}VGa. These features suggest that the positive hyperfine field at Co nucleus in the Co-based Heusler alloys is due to conduction electron polarization rather than a transferred hyperfine field.

  19. MAGNET

    CERN Multimedia

    by B. Curé

    2011-01-01

    The magnet operation was very satisfactory till the technical stop at the end of the year 2010. The field was ramped down on 5th December 2010, following the successful regeneration test of the turbine filters at full field on 3rd December 2010. This will limit in the future the quantity of magnet cycles, as it is no longer necessary to ramp down the magnet for this type of intervention. This is made possible by the use of the spare liquid Helium volume to cool the magnet while turbines 1 and 2 are stopped, leaving only the third turbine in operation. This obviously requires full availability of the operators to supervise the operation, as it is not automated. The cryogenics was stopped on 6th December 2010 and the magnet was left without cooling until 18th January 2011, when the cryoplant operation resumed. The magnet temperature reached 93 K. The maintenance of the vacuum pumping was done immediately after the magnet stop, when the magnet was still at very low temperature. Only the vacuum pumping of the ma...

  20. Investigation of the Chest-Ear Radio Propagation Channel

    DEFF Research Database (Denmark)

    Kvist, Søren Helstrup; Jakobsen, Kaj Bjarne

    2010-01-01

    The path gain (|S21|) between antennas on the chest and at the ear is presented as a function of the position of the antenna on the chest. A monopole antenna and a printed Inverted-F Antenna (IFA) are considered for placement on the chest. The path gain is found by HFSS simulations as well as...

  1. Multi-shot PROPELLER for high-field preclinical MRI

    Science.gov (United States)

    Pandit, Prachi; Qi, Yi; Story, Jennifer; King, Kevin F.; Johnson, G. Allan

    2012-01-01

    With the development of numerous mouse models of cancer, there is a tremendous need for an appropriate imaging technique to study the disease evolution. High-field T2-weighted imaging using PROPELLER MRI meets this need. The 2-shot PROPELLER technique presented here, provides (a) high spatial resolution, (b) high contrast resolution, and (c) rapid and non-invasive imaging, which enables high-throughput, longitudinal studies in free-breathing mice. Unique data collection and reconstruction makes this method robust against motion artifacts. The 2-shot modification introduced here, retains more high-frequency information and provides higher SNR than conventional single-shot PROPELLER, making this sequence feasible at high-fields, where signal loss is rapid. Results are shown in a liver metastases model to demonstrate the utility of this technique in one of the more challenging regions of the mouse, which is the abdomen. PMID:20572138

  2. Low-field MRI can be more sensitive than high-field MRI

    Science.gov (United States)

    Coffey, Aaron M.; Truong, Milton L.; Chekmenev, Eduard Y.

    2013-12-01

    MRI signal-to-noise ratio (SNR) is the key factor for image quality. Conventionally, SNR is proportional to nuclear spin polarization, which scales linearly with magnetic field strength. Yet ever-stronger magnets present numerous technical and financial limitations. Low-field MRI can mitigate these constraints with equivalent SNR from non-equilibrium ‘hyperpolarization' schemes, which increase polarization by orders of magnitude independently of the magnetic field. Here, theory and experimental validation demonstrate that combination of field independent polarization (e.g. hyperpolarization) with frequency optimized MRI detection coils (i.e. multi-turn coils using the maximum allowed conductor length) results in low-field MRI sensitivity approaching and even rivaling that of high-field MRI. Four read-out frequencies were tested using samples with identical numbers of 1H and 13C spins. Experimental SNRs at 0.0475 T were ∼40% of those obtained at 4.7 T. Conservatively, theoretical SNRs at 0.0475 T 1.13-fold higher than those at 4.7 T were possible despite an ∼100-fold lower detection frequency, indicating feasibility of high-sensitivity MRI without technically challenging, expensive high-field magnets. The data at 4.7 T and 0.0475 T was obtained from different spectrometers with different RF probes. The SNR comparison between the two field strengths accounted for many differences in parameters such as system noise figures and variations in the probe detection coils including Q factors and coil diameters.

  3. Systems studies of high-field tokamak ignition experiments

    International Nuclear Information System (INIS)

    A study of the interaction between the physics of ignition and the engineering constraints in the design of compact, high-field tokamak ignition demonstration devices is presented. The studies investigate the effects the various electron and ion thermal diffusivities, which result from the many tokamak scaling laws, have on the design parameters of an ignition device and show the feasibility of building and igniting a compact tokamak (R<1m). The relevant machine technology is discussed

  4. High field optical nonlinearity and the Kramers-Kronig relations.

    Science.gov (United States)

    Wahlstrand, J K; Cheng, Y-H; Milchberg, H M

    2012-09-14

    The nonlinear optical response to high fields is absolutely measured for the noble gas atoms He, Ne, Ar, Kr, and Xe. We find that the response is quadratic in the laser field magnitude up to the ionization threshold of each gas. Its size and quadratic dependence are well predicted by a Kramers-Kronig analysis employing known ionization probabilities, and the results are consistent with calculations using the time-dependent Schrödinger equation.

  5. Another cause of chest pain: Staphylococcus aureus sternal osteomyelitis in an otherwise healthy adult

    Directory of Open Access Journals (Sweden)

    Vacek TP

    2014-09-01

    Full Text Available Thomas P Vacek, Shahnaz Rehman, Shipeng Yu, Ankush Moza, Ragheb Assaly Department of Internal Medicine, The University of Toledo Medical Center, Toledo OH, USAAbstract: Chest pain requires a detailed differential diagnosis with good history-taking skills to differentiate between cardiogenic and noncardiogenic causes. Moreover, when other symptoms such as fever and elevated white blood cell count are involved, it may be necessary to consider causes that include infectious sources. A 53-year-old female with no significant past medical history returned to the hospital with recurrent complaints of chest pain that was constant, substernal, reproducible, and exacerbated with inspiration and expiration. The chest pain was thought to be noncardiogenic, as electrocardiography did not demonstrate changes, and cardiac enzymes were found to be negative for signs of ischemia. The patient's blood cultures were analyzed from a previous admission and were shown to be positive for Staphylococcus aureus. The patient was started empirically on vancomycin, which was later switched to ceftriaxone as the bacteria were more sensitive to this antibiotic. A transthoracic echocardiogram did not demonstrate any vegetation or signs of endocarditis. There was a small right pleural effusion discovered on X-ray. Therefore, computed tomography as well as magnetic resonance imaging of the chest were performed, and showed osteomyelitis of the chest. The patient was continued on intravenous ceftriaxone for a total of 6 weeks. Tests for HIV, hepatitis A, B, and C were all found to be negative. The patient had no history of childhood illness, recurrent infections, or previous trauma to the chest, and had had no recent respiratory infections, pneumonia, or any underlying lung condition. Hence, her condition was thought to be a case of primary sternal osteomyelitis without known cause.Keywords: substernal, pleuritic, myocardial infarction, differential

  6. Hole-exciton interaction induced high field decay of magneto-electroluminescence in Alq3-based organic light-emitting diodes at room temperature

    International Nuclear Information System (INIS)

    The magnetic field effects on the electroluminescence of aluminium tris-(8-hydroxyqinoline) (Alq3) based organic light emitting diodes have been investigated by varying the electron/hole ratio in the emissive layer. Experimental results reveal that a negative high field effect in the magneto-electroluminescence (MEL) can be found in devices with very low triplet exciton concentration at room temperature. This suggests triplet-triplet annihilation cannot be used to explain the negative high field MEL in the Alq3 system. Our results suggest that hole-exciton interaction may be the origin of the negative high field MEL and also, in parallel with this interaction, there is also the more common positive high field process occurring which has been tentatively attributed to electron-exciton interactions. The competition between these different processes decides the final shape of the MEL at high fields

  7. Hole-exciton interaction induced high field decay of magneto-electroluminescence in Alq{sub 3}-based organic light-emitting diodes at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Tingting; Holford, D. F.; Gu, Hang; Kreouzis, T. [Materials Research Institute and School of Physics and Astronomy, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom); Zhang, Sijie, E-mail: Sijie.zhang@scu.edu.cn, E-mail: w.gillin@qmul.ac.uk [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Gillin, W. P., E-mail: Sijie.zhang@scu.edu.cn, E-mail: w.gillin@qmul.ac.uk [Materials Research Institute and School of Physics and Astronomy, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom); College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China)

    2016-01-11

    The magnetic field effects on the electroluminescence of aluminium tris-(8-hydroxyqinoline) (Alq{sub 3}) based organic light emitting diodes have been investigated by varying the electron/hole ratio in the emissive layer. Experimental results reveal that a negative high field effect in the magneto-electroluminescence (MEL) can be found in devices with very low triplet exciton concentration at room temperature. This suggests triplet-triplet annihilation cannot be used to explain the negative high field MEL in the Alq{sub 3} system. Our results suggest that hole-exciton interaction may be the origin of the negative high field MEL and also, in parallel with this interaction, there is also the more common positive high field process occurring which has been tentatively attributed to electron-exciton interactions. The competition between these different processes decides the final shape of the MEL at high fields.

  8. Digital chest radiography: collimation and dose reduction

    DEFF Research Database (Denmark)

    Debess, Jeanne; Johnsen, Karen Kirstine; Vejle-Sørensen, Jens Kristian;

    Purpose: Quality improvement of basic radiography focusing on collimation and dose reduction in digital chest radiography Methods and Materials:A retrospective study of digital chest radiography is performed to evaluate the primary x-ray tube collimation of the PA and lateral radiographs. Data from...... one hundred fifty self-reliant female patients between 15 and 55 years of age are included in the study. The clinical research is performed between September and November 2014 where 3rd year Radiography students collect data on four Danish x-ray departments using identical procedures under guidance...... of clinical supervisors. Optimal collimation is determined by European and Regional Danish guidelines. The areal between current and optimal collimation is calculated. The experimental research is performed in September - October 2014 Siemens Axiom Aristos digital radiography system DR using 150 kV, 1,25 -3...

  9. Salmonella typhimurium abscess of the chest wall

    OpenAIRE

    Tonziello, Gilda; Valentinotti, Romina; Arbore, Enrico; Cassetti, Paolo; Luzzati, Roberto

    2013-01-01

    Patient: Male, 73 Final Diagnosis: Salmonella typhimurium abscess of the chest wall Symptoms: — Medication: Ciprofloxacin Clinical Procedure:— Specialty: Infectious Diseases Objective: Unusual clinical course Background: Non-typhoid Salmonella extra-intestinal infections usually develop in infants and in adult patients with pre-existing predisposing conditions. Blood stream infections and urinary tract infections are the most common clinical presentations, but other sites of infection may be ...

  10. Primary Burkitt Lymphoma of the Chest Wall

    OpenAIRE

    Rommel Lu

    2012-01-01

    Burkitt lymphoma (BL) originating in the skin and soft tissue at any site is exceedingly rare. This paper is about a case of primary sporadic BL that presented as an isolated, rapidly enlarging chest wall mass arising from skin and/or soft tissue in an adult. As with other BL presentations, this patient was treated with aggressive chemotherapy with central nervous system (CNS) chemoprophylaxis, but he later died because of sepsis.

  11. Primary Burkitt Lymphoma of the Chest Wall

    Directory of Open Access Journals (Sweden)

    Rommel Lu

    2012-01-01

    Full Text Available Burkitt lymphoma (BL originating in the skin and soft tissue at any site is exceedingly rare. This paper is about a case of primary sporadic BL that presented as an isolated, rapidly enlarging chest wall mass arising from skin and/or soft tissue in an adult. As with other BL presentations, this patient was treated with aggressive chemotherapy with central nervous system (CNS chemoprophylaxis, but he later died because of sepsis.

  12. Reconstruction of chest, abdominal walls and perineum

    OpenAIRE

    Vijaykumar D; Vijayaraghavan Sundeep

    2007-01-01

    The structural integrity of the chest and abdominal walls and perineum is frequently altered by cancer extirpation. Advances in reconstructive surgery and the availability of innovative techniques have helped the cancer surgeon to proceed with radical excisions with minimum morbidity. The ability to harvest flaps from distant sites and the availability of good prosthetic materials have now become part of the routine armamentarium of the plastic surgeon engaged in reconstructive surgery of the...

  13. Effective dose from chest tomosynthesis in children

    International Nuclear Information System (INIS)

    Tomosynthesis (digital tomography) is a recently introduced low-dose alternative to CT in the evaluation of the lungs in patients with cystic fibrosis and pulmonary nodules. Previous studies have reported an adult effective dose of 0.12-0.13 mSv for chest tomosynthesis. The aim of this study was to determine the paediatric effective dose from the dose-area-product. During a 3-y period, 38 children with cystic fibrosis and 36 paediatric oncology patients were examined with chest tomosynthesis, totally 169 posteroanterior and 17 anteroposterior examinations (40 boys and 34 girls, mean age 13.7 y, range 7-20 y). Using recently reported paediatric chest tomosynthesis conversion factors (0.23-1.09 mSv Gy cm-2) corrected for sex, age and energy, the mean posteroanterior effective dose calculated was 0.17 mSv; using the proposed simplified conversion factors of 0.6 (8-10 y), 0.4 (11-14 y) and 0.3 mSv Gy cm-2 (15-19 y), the mean posteroanterior effective dose calculated was 0.15 mSv. As the difference in the calculated effective dose was minor, it is recommendable to use the simplified conversion factors. Using the conversion factor for adult chest tomosynthesis (0.26 mSv Gy cm-2), the mean effective dose was 0.11 mSv. Anteroposterior exposures had considerably higher effective dose. By using conversion factors adapted for children, the calculated risks from radiologic procedures will be more accurate. (authors)

  14. Injuries of the chestFNx01

    Directory of Open Access Journals (Sweden)

    Deodhar S

    1979-01-01

    Full Text Available Thirty cases of chest injuries were admitted in the Department of Surgery, K.E.M. Hospital, Bombay. These injuries seem to be fairly common. Detailed examination at the time of admission is necessary to assess the clinical presentation and the presence of major complications. Institution of intra-peritoneal drainage, restoration of negative intra-pleural pressure and active respiratory physiotherapy constitute an important part of the treatment. The literature on this subject is briefly reviewed

  15. MAGNET

    CERN Multimedia

    Benoit Curé

    2010-01-01

    Operation of the magnet has gone quite smoothly during the first half of this year. The magnet has been at 4.5K for the full period since January. There was an unplanned short stop due to the CERN-wide power outage on May 28th, which caused a slow dump of the magnet. Since this occurred just before a planned technical stop of the LHC, during which access in the experimental cavern was authorized, it was decided to leave the magnet OFF until 2nd June, when magnet was ramped up again to 3.8T. The magnet system experienced a fault also resulting in a slow dump on April 14th. This was triggered by a thermostat on a filter choke in the 20kA DC power converter. The threshold of this thermostat is 65°C. However, no variation in the water-cooling flow rate or temperature was observed. Vibration may have been the root cause of the fault. All the thermostats have been checked, together with the cables, connectors and the read out card. The tightening of the inductance fixations has also been checked. More tem...

  16. MAGNET

    CERN Multimedia

    B. Curé

    2012-01-01

      Following the unexpected magnet stops last August due to sequences of unfortunate events on the services and cryogenics [see CMS internal report], a few more events and initiatives again disrupted the magnet operation. All the magnet parameters stayed at their nominal values during this period without any fault or alarm on the magnet control and safety systems. The magnet was stopped for the September technical stop to allow interventions in the experimental cavern on the detector services. On 1 October, to prepare the transfer of the liquid nitrogen tank on its new location, several control cables had to be removed. One cable was cut mistakenly, causing a digital input card to switch off, resulting in a cold-box (CB) stop. This tank is used for the pre-cooling of the magnet from room temperature down to 80 K, and for this reason it is controlled through the cryogenics control system. Since the connection of the CB was only allowed for a field below 2 T to avoid the risk of triggering a fast d...

  17. MAGNET

    CERN Multimedia

    B. Curé

    2012-01-01

      The magnet was energised at the beginning of March 2012 at a low current to check all the MSS safety chains. Then the magnet was ramped up to 3.8 T on 6 March 2012. Unfortunately two days later an unintentional switch OFF of the power converter caused a slow dump. This was due to a misunderstanding of the CCC (CERN Control Centre) concerning the procedure to apply for the CMS converter control according to the beam-mode status at that time. Following this event, the third one since 2009, a discussion was initiated to define possible improvement, not only on software and procedures in the CCC, but also to evaluate the possibility to upgrade the CMS hardware to prevent such discharge from occurring because of incorrect procedure implementations. The magnet operation itself was smooth, and no power cuts took place. As a result, the number of magnetic cycles was reduced to the minimum, with only two full magnetic cycles from 0 T to 3.8 T. Nevertheless the magnet suffered four stops of the cryogeni...

  18. VAC® for external fixation of flail chest

    Directory of Open Access Journals (Sweden)

    Rikke Winge

    2012-06-01

    Full Text Available A large anterior chest wall defect following tumor resection was reconstructed with a Gore- Tex® membrane and a combined musculocutaneous rectus femoris and tensor fasciae latae free flap. Subsequent paradoxical respiration impeded weaning from the ventilator. Appliance of Vacuum Assisted Closure® (VAC® resulted in immediate chest wall stability and a decrease in the patient’s need for respiratory support. Shortly thereafter, the VAC® was discontinued and the patient was discharged from the intensive care unit (ICU. This case report is the first to describe the successful use of VAC® as an adjuvant to a one-stage procedure for large thoracic wall reconstruction, allowing sufficient temporary external fixation to eliminate paradoxical respiration and plausibly shorten the stay in the ICU. No adverse effects on flap healing or haemodynamics were recorded. It is likely that external VAC® can improve thoracic stability and pulmonary function in a patient with flail chest and decrease the need for mechanical ventilation.

  19. Lung involvement quantification in chest radiographs

    International Nuclear Information System (INIS)

    Tuberculosis (TB) caused by Mycobacterium tuberculosis, is an infectious disease which remains a global health problem. The chest radiography is the commonly method employed to assess the TB's evolution. The methods for quantification of abnormalities of chest are usually performed on CT scans (CT). This quantification is important to assess the TB evolution and treatment and comparing different treatments. However, precise quantification is not feasible for the amount of CT scans required. The purpose of this work is to develop a methodology for quantification of lung damage caused by TB through chest radiographs. It was developed an algorithm for computational processing of exams in Matlab, which creates a lungs' 3D representation, with compromised dilated regions inside. The quantification of lung lesions was also made for the same patients through CT scans. The measurements from the two methods were compared and resulting in strong correlation. Applying statistical Bland and Altman, all samples were within the limits of agreement, with a confidence interval of 95%. The results showed an average variation of around 13% between the two quantification methods. The results suggest the effectiveness and applicability of the method developed, providing better risk-benefit to the patient and cost-benefit ratio for the institution. (author)

  20. Chest pain associated with moderator band pacing.

    Science.gov (United States)

    Goli, Anil K; Kaszala, Karoly; Osman, Mohammed N; Lucke, John; Carrillo, Roger

    2014-10-01

    A 65-year-old man was evaluated for chronic chest pain that had been present for 8 years after placement of a dual-chamber implantable cardioverter-defibrillator to treat inducible ventricular tachycardia. Previous coronary angiography had revealed nonobstructive coronary artery disease and a left ventricular ejection fraction of 0.45 to 0.50, consistent with mild idiopathic nonischemic cardiomyopathy. Evaluation with chest radiography and transthoracic echocardiography showed the implantable cardioverter-defibrillator lead to be embedded within the right ventricle at the moderator band, which had mild calcification. Treatment included extraction of the dual-coil lead and placement of a new single-coil right ventricular lead at the mid septum. The patient had complete relief of symptoms after the procedure. This case shows that chest pain can be associated with the placement of a right ventricular implantable cardioverter-defibrillator lead in the moderator band and that symptomatic relief can occur after percutaneous lead extraction and the implantation of a new right ventricular lead to the mid septal region.

  1. Surface Chest Motion Decomposition for Cardiovascular Monitoring

    Science.gov (United States)

    Shafiq, Ghufran; Veluvolu, Kalyana C.

    2014-05-01

    Surface chest motion can be easily monitored with a wide variety of sensors such as pressure belts, fiber Bragg gratings and inertial sensors, etc. The current applications of these sensors are mainly restricted to respiratory motion monitoring/analysis due to the technical challenges involved in separation of the cardiac motion from the dominant respiratory motion. The contribution of heart to the surface chest motion is relatively very small as compared to the respiratory motion. Further, the heart motion spectrally overlaps with the respiratory harmonics and their separation becomes even more challenging. In this paper, we approach this source separation problem with independent component analysis (ICA) framework. ICA with reference (ICA-R) yields only desired component with improved separation, but the method is highly sensitive to the reference generation. Several reference generation approaches are developed to solve the problem. Experimental validation of these proposed approaches is performed with chest displacement data and ECG obtained from healthy subjects under normal breathing and post-exercise conditions. The extracted component morphologically matches well with the collected ECG. Results show that the proposed methods perform better than conventional band pass filtering.

  2. High-field paramagnetic Meissner effect and flux creep in low-T c Ti-V alloy superconductors

    Science.gov (United States)

    Matin, M.; Chattopadhyay, M. K.; Sharath Chandra, L. S.; Roy, S. B.

    2016-02-01

    We report an experimental study on the high-field paramagnetic Meissner effect (HFPME) performed by measuring both the temperature and time dependence of magnetization in the two compositions of superconducting Ti-V alloys where certain secondary phases are non-superconducting, and thereby act as efficient pinning centres for the flux lines. While spatially non-uniform flux density driven by flux line pinning at these secondary phases is the necessary condition for the observation of the HFPME, our study indicates that the flux creep effect plays a supplementary role to reinforce the HFPME. It is found that in the temperature and magnetic field regime of the HFPME, the field-cooled magnetization of these samples relaxes monotonically towards a more positive value with elapsed time. We comment on how this paramagnetic relaxation behaviour of the field-cooled magnetization is correlated with the unusual thermo-magnetic responses related to the HFPME.

  3. MAGNET

    CERN Multimedia

    B. Curé

    2012-01-01

      The magnet and its sub-systems were stopped at the beginning of the winter shutdown on 8th December 2011. The magnet was left without cooling during the cryogenics maintenance until 17th January 2012, when the cryoplant operation resumed. The magnet temperature reached 93 K. The vacuum pumping was maintained during this period. During this shutdown, the yearly maintenance was performed on the cryogenics, the vacuum pumps, the magnet control and safety systems, and the power converter and discharge lines. Several preventive actions led to the replacement of the electrovalve command coils, and the 20A DC power supplies of the magnet control system. The filters were cleaned on the demineralised water circuits. The oil of the diffusion pumps was changed. On the cryogenics, warm nitrogen at 343 K was circulated in the cold box to regenerate the filters and the heat exchangers. The coalescing filters have been replaced at the inlet of both the turbines and the lubricant trapping unit. The active cha...

  4. MAGNET

    CERN Multimedia

    Benoit Curé

    2010-01-01

    The magnet was successfully operated at the end of the year 2009 despite some technical problems on the cryogenics. The magnet was ramped up to 3.8 T at the end of November until December 16th when the shutdown started. The magnet operation met a few unexpected stops. The field was reduced to 3.5 T for about 5 hours on December 3rd due to a faulty pressure sensor on the helium compressor. The following day the CERN CCC stopped unintentionally the power converters of the LHC and the experiments, triggering a ramp down that was stopped at 2.7 T. The magnet was back at 3.8 T about 6 hours after CCC sent the CERN-wide command. Three days later, a slow dump was triggered due to a stop of the pump feeding the power converter water-cooling circuit, during an intervention on the water-cooling plant done after several disturbances on the electrical distribution network. The magnet was back at 3.8 T in the evening the same day. On December 10th a break occurred in one turbine of the cold box producing the liquid ...

  5. MAGNET

    CERN Multimedia

    B. Curé

    2011-01-01

    The CMS magnet has been running steadily and smoothly since the summer, with no detected flaw. The magnet instrumentation is entirely operational and all the parameters are at their nominal values. Three power cuts on the electrical network affected the magnet run in the past five months, with no impact on the data-taking as the accelerator was also affected at the same time. On 22nd June, a thunderstorm caused a power glitch on the service electrical network. The primary water cooling at Point 5 was stopped. Despite a quick restart of the water cooling, the inlet temperature of the demineralised water on the busbar cooling circuit increased by 5 °C, up to 23.3 °C. It was kept below the threshold of 27 °C by switching off other cooling circuits to avoid the trigger of a slow dump of the magnet. The cold box of the cryogenics also stopped. Part of the spare liquid helium volume was used to maintain the cooling of the magnet at 4.5 K. The operators of the cryogenics quickly restarted ...

  6. MAGNET

    CERN Multimedia

    B. Curé

    2013-01-01

      The magnet was operated without any problem until the end of the LHC run in February 2013, apart from a CERN-wide power glitch on 10 January 2013 that affected the CMS refrigerator, causing a ramp down to 2 T in order to reconnect the coldbox. Another CERN-wide power glitch on 15 January 2013 didn’t affect the magnet subsystems, the cryoplant or the power converter. At the end of the magnet run, the reconnection of the coldbox at 2.5 T was tested. The process will be updated, in particular the parameters of some PID valve controllers. The helium flow of the current leads was reduced but only for a few seconds. The exercise will be repeated with the revised parameters to validate the automatic reconnection process of the coldbox. During LS1, the water-cooling services will be reduced and many interventions are planned on the electrical services. Therefore, the magnet cryogenics and subsystems will be stopped for several months, and the magnet cannot be kept cold. In order to avoid unc...

  7. Unusual chest wall pain caused by thoracic disc herniation in a professional baseball pitcher.

    Science.gov (United States)

    Kato, Kinshi; Yabuki, Shoji; Otani, Koji; Nikaido, Takuya; Otoshi, Ken-Ichi; Watanabe, Kazuyuki; Kikuchi, Shin-Ichi; Konno, Shin-Ichi

    2016-06-01

    Symptomatic thoracic disc herniation is clinically rare. There are few cases of disc herniation of the thoracic spine in top athletes described in the literature. We herein present a rare case of chest wall pain due to thoracic disc herniation in a professional baseball pitcher. A 30-year-old, left-handed pitcher complained of left-sided chest wall pain in the region of his lower ribs during a game. Neurological examination revealed hypoesthesia of the left side of the chest at the level of the lower thoracic spine. Magnetic resonance imaging (MRI) of the thoracic spine showed a left-sided paramedian disc herniation at the T9-T10 level. The player was initially prescribed rest, administration of pregabalin (150 mg twice a day), and subsequent physical rehabilitation. He was able to resume full training and pitching without medication 6 months after the onset. A follow-up MRI of the thoracic spine showed a reduction in the size of the herniated disc compared to the initial findings. Though relatively rare, thoracic disc herniation should be considered in cases of chest wall pain in athletes. PMID:26983590

  8. MAGNETS

    Science.gov (United States)

    Hofacker, H.B.

    1958-09-23

    This patent relates to nmgnets used in a calutron and more particularly to means fur clamping an assembly of magnet coils and coil spacers into tightly assembled relation in a fluid-tight vessel. The magnet comprises windings made up of an assembly of alternate pan-cake type coils and spacers disposed in a fluid-tight vessel. At one end of the tank a plurality of clamping strips are held firmly against the assembly by adjustable bolts extending through the adjacent wall. The foregoing arrangement permits taking up any looseness which may develop in the assembly of coils and spacers.

  9. Detecting breast microcalcifications with high-field MRI.

    Science.gov (United States)

    de Leeuw, Hendrik; Stehouwer, Bertine L; Bakker, Chris J G; Klomp, Dennis W J; van Diest, Paul J; Luijten, Peter R; Seevinck, Peter R; van den Bosch, Maurice A A J; Viergever, Max A; Veldhuis, Wouter B

    2014-05-01

    The aim of this study was to detect microcalcifications in human whole breast specimens using high-field MRI. Four mastectomy specimens, obtained with approval of the institutional review board, were subjected to gradient-echo MRI acquisitions on a high-field MR scanner. The phase derivative was used to detect microcalcifications. The echo time and imaging resolution were varied to study the sensitivity of the proposed method. Computed tomography images of the mastectomy specimens and prior acquired mammography images were used to validate the results. A template matching algorithm was designed to detect microcalcifications automatically. The three spatial derivatives of the signal phase surrounding a field-perturbing object allowed three-dimensional localization, as well as the discrimination of diamagnetic field-perturbing objects, such as calcifications, and paramagnetic field-perturbing structures, e.g. blood. A longer echo time enabled smaller disturbances to be detected, but also resulted in shading as a result of other field-disturbing materials. A higher imaging resolution increased the detection sensitivity. Microcalcifications in a linear branching configuration that spanned over 8 mm in length were detected. After manual correction, the automatic detection tool identified up to 18 microcalcifications within the samples, which was in close agreement with the number of microcalcifications found on previously acquired in vivo mammography images. Microcalcifications can be detected by MRI in human whole breast specimens by the application of phase derivative imaging. PMID:24535752

  10. MAGNET

    CERN Multimedia

    B. Curé

    2011-01-01

    The magnet ran smoothly in the last few months until a fast dump occurred on 9th May 2011. Fortunately, this occurred in the afternoon of the first day of the technical stop. The fast dump was due to a valve position controller that caused the sudden closure of a valve. This valve is used to regulate the helium flow on one of the two current leads, which electrically connects the coil at 4.5 K to the busbars at room temperature. With no helium flow on the lead, the voltage drop and the temperatures across the leads increase up to the defined thresholds, triggering a fast dump through the Magnet Safety System (MSS). The automatic reaction triggered by the MSS worked properly. The helium release was limited as the pressure rise was just at the limit of the safety valve opening pressure. The average temperature of the magnet reached 72 K. It took four days to recover the temperature and refill the helium volumes. The faulty valve controller was replaced by a spare one before the magnet ramp-up resumed....

  11. Segmentation of ribs in digital chest radiographs

    Science.gov (United States)

    Cong, Lin; Guo, Wei; Li, Qiang

    2016-03-01

    Ribs and clavicles in posterior-anterior (PA) digital chest radiographs often overlap with lung abnormalities such as nodules, and cause missing of these abnormalities, it is therefore necessary to remove or reduce the ribs in chest radiographs. The purpose of this study was to develop a fully automated algorithm to segment ribs within lung area in digital radiography (DR) for removal of the ribs. The rib segmentation algorithm consists of three steps. Firstly, a radiograph was pre-processed for contrast adjustment and noise removal; second, generalized Hough transform was employed to localize the lower boundary of the ribs. In the third step, a novel bilateral dynamic programming algorithm was used to accurately segment the upper and lower boundaries of ribs simultaneously. The width of the ribs and the smoothness of the rib boundaries were incorporated in the cost function of the bilateral dynamic programming for obtaining consistent results for the upper and lower boundaries. Our database consisted of 93 DR images, including, respectively, 23 and 70 images acquired with a DR system from Shanghai United-Imaging Healthcare Co. and from GE Healthcare Co. The rib localization algorithm achieved a sensitivity of 98.2% with 0.1 false positives per image. The accuracy of the detected ribs was further evaluated subjectively in 3 levels: "1", good; "2", acceptable; "3", poor. The percentages of good, acceptable, and poor segmentation results were 91.1%, 7.2%, and 1.7%, respectively. Our algorithm can obtain good segmentation results for ribs in chest radiography and would be useful for rib reduction in our future study.

  12. Pitfalls and variants in pediatric chest imaging.

    Science.gov (United States)

    García Asensio, D; Fernández Martín, M

    2016-05-01

    Most pitfalls in the interpretation of pediatric chest imaging are closely related with the technique used and the characteristics of pediatric patients. To obtain a quality image that will enable the correct diagnosis, it is very important to use an appropriate technique. It is important to know how technical factors influence the image and to be aware of the possible artifacts that can result from poor patient cooperation. Moreover, radiologists need to be familiar with the normal anatomy in children, with the classic radiologic findings, and with the anatomic and developmental variants to avoid misinterpreting normal findings as pathological.

  13. Radiological diagnosis and therapy of chest pain

    International Nuclear Information System (INIS)

    The causes and localization of chest pain are numerous. They can derive from infections, traumas, or tumors. Possible sites of origin are: skeletal portions, vertebral column, ribs, and sternum, as well as mediastinum and pleura. In women, occurrence tends to be cyclic and affect the mamma region. Radiological diagnosis includes radiography, nuclear techniques as well as whole body computer-tomography. Radiation therapy is indicated in cases of mediastinal tumor formation. Radiation of painful osteolytic vertebral metastases and rib destructions proves to be an efficient palliative measure. (orig.)

  14. B0 mapping with multi-channel RF coils at high field.

    Science.gov (United States)

    Robinson, Simon; Jovicich, Jorge

    2011-10-01

    Mapping the static magnetic field via the phase evolution over gradient echo scans acquired at two or more echo times is an established method. A number of possibilities exist, however, for combining phase data from multi-channel coils, denoising and thresholding field maps for high field applications. Three methods for combining phase images when no body/volume coil is available are tested: (i) Hermitian product, (ii) phase-matching over channels, and (iii) a new approach based on calculating separate field maps for each channel. The separate channel method is shown to yield field maps with higher signal-to-noise ratio than the Hermitian product and phase-matching methods and fewer unwrapping errors at low signal-to-noise ratio. Separate channel combination also allows unreliable voxels to be identified via the standard deviation over channels, which is found to be the most effective means of denoising field maps. Tests were performed using multichannel coils with between 8 and 32 channels at 3 T, 4 T, and 7 T. For application in the correction of distortions in echo-planar images, a formulation is proposed for reducing the local gradient of field maps to eliminate signal pile-up or swapping artifacts. Field maps calculated using these techniques, implemented in a freely available MATLAB toolbox, provide the basis for an effective correction for echo-planar imaging distortions at high fields. PMID:21608027

  15. High field volume coil with unbalance current distribution for MRI applications of rodents

    Science.gov (United States)

    Marrufo, O. R.; Hernández, J.; Rodríguez, A. O.

    2010-12-01

    The development of transceiver volume coils for high field MRI is still a very dynamic field of investigation and development Temnikov has been recently proposed a new volume coil design, similar to the to the gradiometer coil. It is also claimed that it is possible to individually tune it with a single chip capacitor. This motivated the development of a coil prototype based on this idea for whole-body MRI of rodents at 7 Tesla. Electromagnetic simulations of the RF field generated by this coil design were previously performed to study its properties. Electromagnetic simulations were also conducted for a standard birdcage coil with similar dimensions for fare comparison. In all numerical simulations, an unbalanced currents distribution was assumed by applying half the current intensity to designated legs. This coil design operated in the transceiver mode and was linear-driven. The coil size was manufactured to accommodate small rodents. Numerical simulations showed a field uniformity improvement of our coil over the standard birdcage coil. A popular birdcage coil was also constructed to compare their performances. Phantom and rat images were acquired for both volume coils to prove the viability of this coil design for high field MRI applications and standard spin echo pulse sequences Thus, these preliminary results make this coil design a good candidate for MRI and MRS applications of high magnetic fields.

  16. Test results of HD2, a high field Nb$_{3}$Sn dipole with a 36 mm bore

    CERN Document Server

    Ferracin, P

    2009-01-01

    The Superconducting Magnet Program at Lawrence Berkeley National Laboratory (LBNL) has developed the 1 m long Nb3Sn dipole magnet HD2. With tilted (flared) ends to avoid obstructing a 36 mm clear bore, HD2 represents a step towards the use of block-type coils in high-field accelerator magnets. The coil design has been optimized to minimize geometric harmonics and reduce the conductor peak field in the end region, resulting in an expected short sample dipole field of 15 T. The support structure is composed by an external aluminum shell pretensioned with pressurized bladders and interference keys, and by two stainless steel end plates compressing the coil ends through four aluminum axial rods. We report on magnet design, assembly, and test results, including training performance, quench locations, and strain gauge measurements

  17. Bacteriological research for the contamination of equipment in chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Seung Gu; Song, Woon Heung; Kweon, Dae Cheol [Shinhan University, Uijeongbu (Korea, Republic of)

    2015-12-15

    The purpose is to determine the degree of contamination of the equipment for infection control in chest radiography of the radiology department. We confirmed by chemical and bacterial identification of bacteria of the equipment and established a preventive maintenance plan. Chest X-ray radiography contact area on the instrument patients shoulder, hand, chin, chest lateral radiography patient contact areas with a 70% isopropyl alcohol cotton swab were compared to identify the bacteria before and after sterilization on the patient contact area in the chest radiography equipment of the department. The gram positive Staphylococcus was isolated from side shoots handle before disinfection in the chest radiography equipment. For the final identification of antibiotic tested that it was determined by performing the nobobiocin to the sensitive Staphylococcus epidermidis. Chest radiography equipment before disinfecting the handle side of Staphylococcus epidermidis bacteria were detected using a disinfectant should be to prevent hospital infections.

  18. Effectiveness of chest physiotherapy in the management of bronchiectasis

    International Nuclear Information System (INIS)

    Bronchiectasis is a chronic disease in which clearance of sputum is disturbed because bronchi dilated permanently. So for the clearance of sputum we have to use physiotherapy techniques such as postural drainage percussion and vibration (PDPY), active cycle of breathing technique (ACBT), autogenic drainage, positive expiratory pressure, high frequency chest wall oscillation. Objective: To determine the role of Chest Physical therapy intervention in the management of Bronchi ectasis. To compare the prognosis of bronchiectasis with and without chest physiotherapy. Methodology: Data was collected from Gulab Devi Chest Hospital, Lahore. A Randomized Control Trial (RCT) study method was used and 60 patients are studied. In this study, they were divided into 03 groups 1- Antibiotics Therapy 2-Chest Physical therapy 3-Antibiotics and Chest Physical therapy. Each group consistant. (author)

  19. High-Gain High-Field Fusion Plasma

    Science.gov (United States)

    Li, Ge

    2015-10-01

    A Faraday wheel (FW)—an electric generator of constant electrical polarity that produces huge currents—could be implemented in an existing tokamak to study high-gain high-field (HGHF) fusion plasma, such as the Experimental Advanced Superconducting Tokamak (EAST). HGHF plasma can be realized in EAST by updating its pulsed-power system to compress plasma in two steps by induction fields; high gains of the Lawson trinity parameter and fusion power are both predicted by formulating the HGHF plasma. Both gain rates are faster than the decrease rate of the plasma volume. The formulation is checked by earlier ATC tests. Good agreement between theory and tests indicates that scaling to over 10 T at EAST may be possible by two-step compressions with a compression ratio of the minor radius of up to 3. These results point to a quick new path of fusion plasma study, i.e., simulating the Sun by EAST.

  20. The new high field photoexcitation muon spectrometer at the ISIS pulsed neutron and muon source

    CERN Document Server

    Yokoyama, K; Murahari, P; Wang, K; Dunstan, D J; Waller, S P; McPhail, D J; Hillier, A D; Henson, J; Harper, M R; Heathcote, P; Drew, A J

    2016-01-01

    A high power pulsed laser system has been installed on the high magnetic field muon instrument (HiFi) at the ISIS pulsed neutron and muon source, situated at the STFC Rutherford Appleton Laboratory in the UK. The upgrade enables one to perform light-pump muon-probe experiments under a high field, which opens up a brand-new area in the muon spin spectroscopy. In this report we overview the principle of the HiFi Laser system, and describe the newly developed techniques and devices that enable a controlled photoexcitation in the muon instrument. A demonstration experiment illustrates the unique combination of the photoexcited system and avoided level crossing technique.

  1. ANALYSIS OF HIGH FIELD NON-LINEAR LOSSES ON SRF SURFACES DUE TO SPECIFIC TOPOGRAPHIC ROUGHNESS

    Energy Technology Data Exchange (ETDEWEB)

    Chen Xu,Charles Reece,Michael Kelley

    2012-07-01

    The high-field performance of SRF cavities will eventually be limited by the realization of fundamental material limits, whether it is Hc1 or Hsh, or some derivative thereof, at which the superconductivity is lost. Before reaching this fundamental field limit at the macro level, it must be encountered at localized, perhaps microscopic, sites of field enhancement due to local topography. If such sites are small enough, they may produce thermally stabilized normal-conducting regions which contribute non-linear losses when viewed from the macro resonant field perspective, and thus produce degradation in Q0. We have undertaken a calculation of local surface magnetic field enhancement from specific fine topographic structure by conformal mapping method and numerically. A solution of the resulting normal conducting volume has been derived and the corresponding RF Ohmic loss simulated.

  2. MAGNET

    CERN Multimedia

    B. Curé

    MAGNET During the winter shutdown, the magnet subsystems went through a full maintenance. The magnet was successfully warmed up to room temperature beginning of December 2008. The vacuum was broken later on by injecting nitrogen at a pressure just above one atmosphere inside the vacuum tank. This was necessary both to prevent any accidental humidity ingress, and to allow for a modification of the vacuum gauges on the vacuum tank and maintenance of the diffusion pumps. The vacuum gauges had to be changed, because of erratic variations on the measurements, causing spurious alarms. The new type of vacuum gauges has been used in similar conditions on the other LHC experiments and without problems. They are shielded against the stray field. The lubricants of the primary and diffusion pumps have been changed. Several minor modifications were also carried out on the equipment in the service cavern, with the aim to ease the maintenance and to allow possible intervention during operation. Spare sensors have been bough...

  3. MAGNET

    CERN Multimedia

    Benoit Curé

    2010-01-01

    The magnet worked very well at 3.8 T as expected, despite a technical issue that manifested twice in the cryogenics since June. All the other magnet sub-systems worked without flaw. The issue in the cryogenics was with the cold box: it could be observed that the cold box was getting progressively blocked, due to some residual humidity and air accumulating in the first thermal exchanger and in the adsorber at 65 K. This was later confirmed by the analysis during the regeneration phases. An increase in the temperature difference between the helium inlet and outlet across the heat exchanger and a pressure drop increase on the filter of the adsorber were observed. The consequence was a reduction of the helium flow, first compensated by the automatic opening of the regulation valves. But once they were fully opened, the flow and refrigeration power reduced as a consequence. In such a situation, the liquid helium level in the helium Dewar decreased, eventually causing a ramp down of the magnet current and a field...

  4. MAGNET

    CERN Multimedia

    Benoit Curé.

    The magnet operation restarted end of June this year. Quick routine checks of the magnet sub-systems were performed at low current before starting the ramps up to higher field. It appeared clearly that the end of the field ramp down to zero was too long to be compatible with the detector commissioning and operations plans. It was decided to perform an upgrade to keep the ramp down from 3.8T to zero within 4 hours. On July 10th, when a field of 1.5T was reached, small movements were observed in the forward region support table and it was decided to fix this problem before going to higher field. At the end of July the ramps could be resumed. On July 28th, the field was at 3.8T and the summer CRAFT exercise could start. This run in August went smoothly until a general CERN wide power cut took place on August 3rd, due to an insulation fault on the high voltage network outside point 5. It affected the magnet powering electrical circuit, as it caused the opening of the main circuit breakers, resulting in a fast du...

  5. MAGNET

    CERN Multimedia

    B. Curé

    2013-01-01

    The magnet is fully stopped and at room temperature. The maintenance works and consolidation activities on the magnet sub-systems are progressing. To consolidate the cryogenic installation, two redundant helium compressors will be installed as ‘hot spares’, to avoid the risk of a magnet downtime in case of a major failure of a compressor unit during operation. The screw compressors, their motors, the mechanical couplings and the concrete blocks are already available and stored at P5. The metallic structure used to access the existing compressors in SH5 will be modified to allow the installation of the two redundant ones. The plan is to finish the installation and commissioning of the hot spare compressors before the summer 2014. In the meantime, a bypass on the high-pressure helium piping will be installed for the connection of a helium drier unit later during the Long Shutdown 1, keeping this installation out of the schedule critical path. A proposal is now being prepared for the con...

  6. EUCARD magnet development

    CERN Document Server

    de Rijk, Gijs

    2011-01-01

    The FP7-EuCARD work package 7 (WP7), "HFM: Superconducting High Field Magnets for higher luminosities and energies" is a collaboration between 12 European institutes and firms with the objective of developing high field magnet technology. WP7 foresees to construct a 13 T dipole with a 100 mm aperture, a B = 6 T high temperature superconductor (HTS) dipole insert, a superconducting HTS link and a superconducting helical undulator.

  7. Evaluation of radiation doses delivered in different chest CT protocols

    OpenAIRE

    Gorycki, Tomasz; Lasek, Iwona; Kamiński, Kamil; Studniarek, Michał

    2014-01-01

    Summary Background There are differences in the reference diagnostic levels for the computed tomography (CT) of the chest as cited in different literature sources. The doses are expressed either in weighted CT dose index (CTDIVOL) used to express the dose per slice, dose-length product (DLP), and effective dose (E). The purpose of this study was to assess the radiation dose used in Low Dose Computer Tomography (LDCT) of the chest in comparison with routine chest CT examinations as well as to ...

  8. Severe Pulmonary Valve Regurgitation 40 Years After Blunt Chest Trauma.

    Science.gov (United States)

    Fuglsang, Simon; Heiberg, Johan; Hjortdal, Vibeke Elisabeth

    2015-10-01

    Severe pulmonary valve regurgitation caused by a pulmonary valve tear is a rare complication to a blunt chest trauma. In this case report, we present a patient with pulmonary regurgitation originating from a chest trauma 40 years ago. Possible mechanisms are osseous pinch of the pulmonary valve between the anterior chest wall and the vertebral column, and retrograde blowout from severe compression of the lungs. PMID:26434447

  9. Chest Radiography Findings in Primary Pulmonary Tuberculosis in Children

    OpenAIRE

    Milković, Đurđica; Richter, Darko; Zoričić-Letoja, Ivka; Raos, Miljenko; Koncul, Ivan

    2005-01-01

    Plain chest radiography plays a major role in the diagnosis and follow-up of pulmonary tuberculosis in childhood. The aim of our study was to investigate the distribution of characteristic chest radiographic findings at diagnosis in children with pulmonary tuberculosis. The age of the patients and the type and localization of radiographic changes at admission were retrospectively analyzed. We reviewed chest radiographs in 204 children admitted from January 1, 1991 until June 30, 1994 for newl...

  10. Spectral characteristics of chest wall breath sounds in normal subjects.

    OpenAIRE

    Gavriely, N; Nissan, M.; Rubin, A. H.; Cugell, D. W.

    1995-01-01

    BACKGROUND--This study was carried out to establish a reliable bank of information on the spectral characteristics of chest wall breath sounds from healthy men and women, both non-smokers and smokers. METHODS--Chest wall breath sounds from 272 men and 81 women were measured using contact acoustic sensors, amplifiers, and fast Fourier transform (FFT) based spectral analysis software. Inspiratory and expiratory sounds were picked up at three standard locations on the chest wall during breathing...

  11. Optical compensation device for chest film radiography

    Science.gov (United States)

    Gould, Robert G.; Hasegawa, Bruce H.; DeForest, Sherman E.; Schmidt, Gregory W.; Hier, Richard G.

    1990-07-01

    Although chest radiography is the most commonly performed radiographic examination and one of the most valuable and cost-effective studies in medicine it suffers from relatively high error rates in both missing pathology and false positive interpretations. Detectability of lung nodules and other structures in underpenetrated regions of the chest film can be improved by both exposure and optical compensation but current compensation systems require major capital cost or a significant change in normal clinical practice. A new optical compensation system called the " Intelligent X-Ray Illuminator" (IXI) automatically and virtually instantaneously generates a patient-specific optical unsharp mask that is projected directly on a radiograph. When a radiograph is placed on the IXI which looks much like a conventional viewbox it acquires a low-resolution electronic image of this film from which the film transmission is derived. The transmission information is inverted and blurred in an image processor to form an unsharp mask which is fed into a spatial light modulator (SLM) placed between a light source and the radiograph. The SLM tailors the viewbox luminance by decreasing illumination to underexposed (i. e. transmissive) areas of the radiograph presenting the observer with an optically unsharp-masked image. The IXI uses the original radiograph and will allow it to be viewed on demand with conventional (uniform illumination. Potentially the IXI could introduce the known beneficial aspects of optical unsharp masking into radiology at low capital

  12. Chest Traumas due to Fall in Childhood

    Directory of Open Access Journals (Sweden)

    Ufuk Cobanoglu

    2011-09-01

    Full Text Available Aim: Falls are the most common reason for childhood traumas. The aim of this study is to investigate the causes, types, monthly frequencies and results f injuries due to fall of children in our region and to recommend somep recautions for preventing these injuries. Material and Methods: A retrospective evaluation was performed in 47 pediatric patients admitted to the Department of Thoracic Surgery during 2006-2009 with a diagnosis of chest trauma due to fall. For every patient, a pediatric trauma score (PTS was calculated. Descriptive statistics were performed for PTS and the duration of hospital stay. Results: The mean PTS of the cases who had additional system injuries were significantly worse than the cases who had isolated chest traumas. Similarly, the length of hospital stay was also much longer in the cases with associated system injuries.Conclusions: Injuries occur mostly in summer season. It may be due to the fact that the children do not go to the school and usually spend their times outside in this period. The children and their parents should be educated about the prevention of these accidents. Additionally, the accident and injury rates may also be reduced by constructing safer games and sports grounds with robust infrastructure.

  13. Cross-chest liposuction in gynaecomastia

    Directory of Open Access Journals (Sweden)

    Biju Murali

    2011-01-01

    Full Text Available Background: Gynaecomastia is usually treated with liposuction or liposuction with excision of the glandular tissue. The type of surgery chosen depends on the grade of the condition. Objective: Because gynaecomastia is treated primarily as a cosmetic procedure, we aimed at reducing the invasiveness of the surgery. Materials and Methods: The technique complies with all recommended protocols for different grades of gynaecomastia. It uses liposuction, gland excision, or both, leaving only minimal post-operative scars. The use of cross-chest liposuction through incisions on the edge of the areola helps to get rid of all the fat under the areola without an additional scar as in the conventional method. Results: This is a short series of 20 patients, all with bilateral gynaecomastia (i.e., 40 breasts, belonging to Simon′s Stage 1 and 2, studied over a period of 2 years. The average period of follow-up was 15 months. Post-operative complications were reported in only two cases, with none showing long-term complications or issues specifically due to the procedure. Conclusions : Cross-chest liposuction for gynaecomastia is a simple yet effective surgical tool in bilateral gynaecomastia treatment to decrease the post-operative scars. The use of techniques like incision line drain placement and post-drain removal suturing of wounds aid in decreasing the scar.

  14. Acute chest pain emergencies - spouses' prehospital experiences.

    Science.gov (United States)

    Forslund, Kerstin; Quell, Robin; Sørlie, Venke

    2008-10-01

    The call to the Emergency Medical Dispatch Centre is often a person's first contact with the health-care system in cases of acute illness or injury and acute chest pain is a common reason for calling. The aim was to illuminate how spouses to persons with acute chest pain experienced the alarm situation, the emergency call and the prehospital emergency care. Interviews were conducted with nineteen spouses. A phenomenological-hermeneutic approach was used for the analyses. The themes responsibility and uneasiness emerged as well as an overall theme of aloneness. Being a spouse to a person in need of acute medical and nursing assistance was interpreted as "Being responsible and trying to preserve life" and "Being able to manage the uneasiness and having trust in an uncertain situation." When their partners' life was at risk the spouses were in an escalating spiral of worry, uncertainty, stress, fear of loss, feeling of loneliness and desperation. They had to manage emotional distress and felt compelled to act to preserve life, a challenging situation. PMID:18929341

  15. Multidetector Computer Tomography: Evaluation of Blunt Chest Trauma in Adults

    Directory of Open Access Journals (Sweden)

    João Palas

    2014-01-01

    Full Text Available Imaging plays an essential part of chest trauma care. By definition, the employed imaging technique in the emergency setting should reach the correct diagnosis as fast as possible. In severe chest blunt trauma, multidetector computer tomography (MDCT has become part of the initial workup, mainly due to its high sensitivity and diagnostic accuracy of the technique for the detection and characterization of thoracic injuries and also due to its wide availability in tertiary care centers. The aim of this paper is to review and illustrate a spectrum of characteristic MDCT findings of blunt traumatic injuries of the chest including the lungs, mediastinum, pleural space, and chest wall.

  16. Multidetector Computer Tomography: Evaluation of Blunt Chest Trauma in Adults

    International Nuclear Information System (INIS)

    Imaging plays an essential part of chest trauma care. By definition, the employed imaging technique in the emergency setting should reach the correct diagnosis as fast as possible. In severe chest blunt trauma, multidetector computer tomography (MDCT) has become part of the initial workup, mainly due to its high sensitivity and diagnostic accuracy of the technique for the detection and characterization of thoracic injuries and also due to its wide availability in tertiary care centers. The aim of this paper is to review and illustrate a spectrum of characteristic MDCT findings of blunt traumatic injuries of the chest including the lungs, mediastinum, pleural space, and chest wall.

  17. Staphylococcus aureus sternal osteomyelitis: a rare cause of chest pain

    Directory of Open Access Journals (Sweden)

    Kaur M

    2015-10-01

    Full Text Available Chest pain is a common presenting symptom with a broad differential. Life-threatening cardiac and pulmonary etiologies of chest pain should be evaluated first. However, it is critical to perform a thorough assessment for other sources of chest pain in order to limit morbidity and mortality from less common causes. We present a rare case of a previously healthy 45 year old man who presented with focal, substernal, reproducible chest pain and Staphylococcus aureus bacteremia who was later found to have primary Staphylococcus aureus sternal osteomyelitis.

  18. Chest trauma in children: current imaging guidelines and techniques.

    LENUS (Irish Health Repository)

    Moore, Michael A

    2011-09-01

    Given the heterogeneous nature of pediatric chest trauma, the optimal imaging approach is tailored to the specific patient. Chest radiography remains the most important imaging modality for initial triage. The decision to perform a chest computed tomography scan should be based on the nature of the trauma, the child\\'s clinical condition, and the initial radiographic findings, taking the age-related pretest probabilities of serious injury into account. The principles of as low as reasonably achievable and Image Gently should be followed. The epidemiology and pathophysiology, imaging techniques, characteristic findings, and evidence-based algorithms for pediatric chest trauma are discussed.

  19. HIFI - a dedicated HIgh-FIeld diffraction and spectroscopy instrument

    International Nuclear Information System (INIS)

    The outstanding scientific impact of single-crystal neutron diffraction and spectroscopy in steady state vertical magnetic fields up to 15 T (17 T without dilution fringe) is reflected in numerous high-profile publications. Magnetic fields 30 T - 35 T in vertical geometry allow to address enigmatic questions without equivalence at lower fields. The constraints implied by such magnetic fields demand a specially designed dedicated instrument. Since the vertical field geometry is crucial for single-crystal diffraction as well as spectroscopy, the solid angle of scattered neutrons is restricted, and a high-flux reactor is best suited to host a corresponding instrument. We propose a world-wide unique versatile instrument for diffraction and spectroscopy in vertical steady fields of 30 T. (authors)

  20. Primary Chest Wall Abscess Mimicking a Breast Tumor That Occurred after Blunt Chest Trauma: A Case Report

    Directory of Open Access Journals (Sweden)

    Yusuke Yamaoka

    2014-01-01

    Full Text Available Primary chest wall abscess occurring after blunt chest trauma is rare. We present the case of a 50-year-old woman who presented with a swelling in her left breast. The patient had experienced blunt chest trauma 2 months back. Needle aspiration revealed pus formation in the patient’s chest. Computed tomography revealed a mass in the lower region of the left mammary gland, with thickening of the parietal pleura and skin and fracture of the fifth rib under the abscess. Following antibiotic administration and irrigation of the affected region, surgical debridement was performed. During surgery, we found that the pectoralis major muscle at the level of the fifth rib was markedly damaged, although the necrotic tissue did not contact the mammary gland. We diagnosed the lesion as a chest wall abscess that occurred in response to blunt chest trauma. Her postoperative course was uneventful. There has been no recurrence for six months after surgery.

  1. Functional MRI and the benefits of ultra-high-field

    International Nuclear Information System (INIS)

    The tremendous impact of MRI on medical diagnosis was recently recognised in the award of the 2003 Nobel Prize for Medicine to Paul Lauterbur and Sir Peter Mansfield. The development, in the last decade or so, of functional magnetic resonance imaging (fMRI), promises no less a revolution in neuroscience, it is the tool with which we can begin to understand the workings of the human mind. This lecture will review the developments which have made this possible; it will also explore future prospects as much stronger magnets (7T and up) become available. (author)

  2. Transceiver 4-leg birdcage for high field MRI: knee imaging

    OpenAIRE

    S.E. Solis; G. Cuellar; R. L. Wang; Tomasi, D; Rodríguez, A.O.

    2008-01-01

    The radiofrequency coil is a crucial component of the magnetic resonance imaging scanners, so that a solid knowledge on the design and physical characteristics is important for those interested in its development. A birdcage coil with a 10 cm radius and 4 legs (length = 12cm), and a separation between the copper strips of 4 cm, was developed for magnetic resonance imaging (MRI) of the human knee and tuned at the resonance frequency of protons at 4 Tesla (170.3 MHz). MR images were acquired wi...

  3. High Field Magnetoresistance of Graphene at the Dirac Point

    Science.gov (United States)

    Checkelsky, Joseph; Li, Lu; Ong, N. P.

    2008-03-01

    The longitudinal and Hall resistance of graphene near the charge neutral point have been studied down to low temperature (20 mK) in high magnetic field (20 T). At issue is the nature of the ground state in the vicinity of the Dirac point in high magnetic fields. In samples in which the offset voltage is small, we observe a highly unusual approach to an insulating state as the field increases. In samples with μ> 0.5 T-1 and V0Hall Ferromagnetism will be discussed in the context of these results.

  4. Short-lived charge-transfer excitons in organic photovoltaic cells studied by high-field magneto-photocurrent.

    Science.gov (United States)

    Devir-Wolfman, Ayeleth H; Khachatryan, Bagrat; Gautam, Bhoj R; Tzabary, Lior; Keren, Amit; Tessler, Nir; Vardeny, Z Valy; Ehrenfreund, Eitan

    2014-07-29

    The main route of charge photogeneration in efficient organic photovoltaic cells based on bulk hetero-junction donor-acceptor blends involves short-lived charge-transfer excitons at the donor-acceptor interfaces. The cell efficiency is critically affected by the charge-transfer exciton recombination and dissociation processes. By measuring the magneto-photocurrent under ambient conditions at room temperature, we show here that magnetic field-induced spin-mixing among the charge-transfer exciton spin sublevels occurs in fields up to at least 8.5 Tesla. The resulting magneto-photocurrent increases at high fields showing non-saturating behaviour up to the highest applied field. We attribute the observed high-field spin-mixing mechanism to the difference in the donor-acceptor g-factors. The non-saturating magneto-photocurrent response at high field indicates that there exist charge-transfer excitons with lifetime in the sub-nanosecond time domain. The non-Lorentzian high-field magneto-photocurrent response indicates a dispersive decay mechanism that originates due to a broad distribution of charge-transfer exciton lifetimes.

  5. High field magnetic resonance background suppression diffusion imaging in the diagnosis of liver foci of space occupying lesion%高场磁共振背景抑制扩散成像技术对肝局灶性占位病变的诊断价值

    Institute of Scientific and Technical Information of China (English)

    李华兵; 肖恩华; 肖立志; 贺忠; 卞读军

    2013-01-01

    Objective: To explore the diagnostic value of the 3.0T magnetic resonance liver diffusion weighted imaging with background suppression (DWIBS) in liver foci of space occupying lesion. Methods: A total of 43 cases of liver bureau stove perch pathological change were included: IS were hepatocellular carcinoma (HCC) with 24 lesions; 7 were liver metastatic tumor with 13 lesions; 10 were liver hemangioma with 12 lesions; and 11 liver cyst with 20 lesions. After taking the conventional T1WI and T2WI sequence, the magnetic resonance background suppression diffusion imaging technology (diffusion weighted imaging with background suppression, DWIBS) was applied, following the dynamic enhanced scan. With the MRI to DWIBS workstation for classifying positron emission computed tomography (PET) processing, the T2WI diagram and dynamic enhanced diagram were compared respectively for the 3 sequences of lesion detection rate, T2WI, and DWIBS, to enhance the delay time between the two joint and combined lesion detection rate. With the MRI workstation software scanning image generation ADC diagram, the ADC values were measured for liver cancer, liver metastatic tumor, liver hemangioma and liver cysts. Results: The 3 sequences of detection rates of the T2WI, DWIBS and enhanced delay period T1WI were 91.3%, 94.2%, and 95.6%. The detection rate of DWIBS plus T2WI was 92.7%; that of T2WI plus enhanced delay time was 94.9%, and that of DWIBS plus enhanced delay time was 96.3%, with the rate of DWIBS plus enhanced delay period obviously higher than that of the DWIBS plus T2WI (P<0.05). The ADC value of the benign liver tumor was obviously higher than that of the malignant tumors: hepatic cyst (2.614±0.57)×l0-3mm2/s, liver hemangioma (2.055±0.21)×10-3mm2/s, metastatic carcinoma (1.374±0.32)×10-3mm2/s, and liver cancer (1.287±0.14)×10-3mm2/s. Except for the liver cancer and the liver metastatic tumor, there was significant difference between the other groups (P<0.05). Conclusion

  6. Comparison of chest compression quality between the modified chest compression method with the use of smartphone application and the standardized traditional chest compression method during CPR.

    Science.gov (United States)

    Park, Sang-Sub

    2014-01-01

    The purpose of this study is to grasp difference in quality of chest compression accuracy between the modified chest compression method with the use of smartphone application and the standardized traditional chest compression method. Participants were progressed 64 people except 6 absentees among 70 people who agreed to participation with completing the CPR curriculum. In the classification of group in participants, the modified chest compression method was called as smartphone group (33 people). The standardized chest compression method was called as traditional group (31 people). The common equipments in both groups were used Manikin for practice and Manikin for evaluation. In the meantime, the smartphone group for application was utilized Android and iOS Operating System (OS) of 2 smartphone products (G, i). The measurement period was conducted from September 25th to 26th, 2012. Data analysis was used SPSS WIN 12.0 program. As a result of research, the proper compression depth (mm) was shown the proper compression depth (p< 0.01) in traditional group (53.77 mm) compared to smartphone group (48.35 mm). Even the proper chest compression (%) was formed suitably (p< 0.05) in traditional group (73.96%) more than smartphone group (60.51%). As for the awareness of chest compression accuracy, the traditional group (3.83 points) had the higher awareness of chest compression accuracy (p< 0.001) than the smartphone group (2.32 points). In the questionnaire that was additionally carried out 1 question only in smartphone group, the modified chest compression method with the use of smartphone had the high negative reason in rescuer for occurrence of hand back pain (48.5%) and unstable posture (21.2%). PMID:24704648

  7. Ultrasonic measurements of chest wall thickness and realistic chest phantom for calibration of Pu lung counting facilities

    International Nuclear Information System (INIS)

    There are four important problems for the measurements of chest wall thickness using ultrasonic device: (1) selection of optimum position of transducer and the number of measured points on the chest covered with detector, (2) estimation of adipose-to-muscle ratio in the chest wall, especially for dispersed adipose like 'marbled beef', (3) determination of regression equations for the prediction of chest wall thickness, derived from groups of different body shape, i.e. corpulent and lean, and (4) estimation of effective chest wall thickness involved self-absorption layer of lung tissue, which changes with distribution of activity in the lungs. This quantity can not be measured with ultrasonic device. Realistic chest phantom was developed. The phantom contains removable model organs (lungs, liver, kidneys and heart), model trachea and artificial rib cage, and also includes chest plates that can be placed over the chest to simulate wide range adipose-to-muscle ratio in the chest wall. Various soft tissue substitutes were made of polyurethane with different concentrations of additive, and the rib cage were made of epoxy resin with calcium carbonate. The experimental data have shown that the phantom can be used as a standard phantom for the calibration. (author)

  8. MAGNET

    CERN Multimedia

    Benoit Curé

    The magnet subsystems resumed operation early this spring. The vacuum pumping was restarted mid March, and the cryogenic power plant was restarted on March 30th. Three and a half weeks later, the magnet was at 4.5 K. The vacuum pumping system is performing well. One of the newly installed vacuum gauges had to be replaced at the end of the cool-down phase, as the values indicated were not coherent with the other pressure measurements. The correction had to be implemented quickly to be sure no helium leak could be at the origin of this anomaly. The pressure measurements have been stable and coherent since the change. The cryogenics worked well, and the cool-down went quite smoothly, without any particular difficulty. The automated start of the turbines had to be fine-tuned to get a smooth transition, as it was observed that the cooling power delivered by the turbines was slightly higher than needed, causing the cold box to stop automatically. This had no consequence as the cold box safety system acts to keep ...

  9. MAGNET

    CERN Multimedia

    B. Curé

    During the winter shutdown, the magnet subsystems went through a full maintenance. The magnet was successfully warmed up to room temperature beginning of December 2008. The vacuum was broken later on by injecting nitrogen at a pressure just above one atmosphere inside the vacuum tank. This was necessary both to prevent any accidental humidity ingress, and to allow for a modification of the vacuum gauges on the vacuum tank and maintenance of the diffusion pumps. The vacuum gauges had to be changed, because of erratic variations on the measurements, causing spurious alarms. The new type of vacuum gauges has been used in similar conditions on the other LHC experiments and without problems. They are shielded against the stray field. The lubricants of the primary and diffusion pumps have been changed. Several minor modifications were also carried out on the equipment in the service cavern, with the aim to ease the maintenance and to allow possible intervention during operation. Spare sensors have been bought. Th...

  10. Alternative Contrast Mechanisms in High Field MR Microscopy.

    Science.gov (United States)

    Engelhardt, Robert Thomas

    1995-01-01

    In high-field MR Microscopy, the T_1 relaxation times may become long and converge while the T_2 relaxation times may become short and converge. As a result, much of the contrast is due solely to differences in spin density. The use of T_{1rho} as an alternative contrast parameter in high-field MR Microscopy has been explored here. To this end, MR Microscopy experiments have been performed using 2.0 and 9.4 Tesla Bruker MRI systems. Spectroscopy experiments at 9.4 Tesla were performed on several phantoms (5.75% agar gel, 1.0 mM MnCl_2, 7.3% and 20% gelatin). Imaging experiments were performed on two, 17.5 day old, perfusion fixed, mouse embryos, embedded in 7.3% gelatin to minimize drying and susceptibility differences. The relaxation times, T_1, T _2, and T_{1rho }, the signal to noise ratios (SNR) and contrast to noise ratios (CNR), have been measured for several types of tissue. The T_{1rho} relaxation times were measured at four locking field strengths, 0.7, 0.9, 1.3 and 1.7 G. T_1 and T_2 imaging experiments were performed using a conventional spin warp imaging sequence. T_{1rho } imaging experiments were performed using a presaturating spin locking pulse, followed by a conventional spin warp imaging sequence. Muscle, diencephalon, lung and liver were chosen for the relaxation time measurements as they offered both good tissue specificity and size. Both static and locking field dispersion of T _{1rho} were observed in the selected mouse embryo tissues. The observed T _{1rho} relaxation times were generally longer than the T_2 relaxation times, increased with locking field strength, and were consistently shorter at 9.4 Tesla than at 2.0 Tesla. The static field dispersion of T_ {1rho} and T_2 are both believed to be due, in part, to diffusion losses through susceptibility induced gradients. The losses are much smaller in the T_{1rho} images, and decrease as the locking pulse is increased. Finally, under certain circumstances, T_{1rho }-weighting could produce

  11. High-field MR imaging of spinal cord multiple sclerosis

    International Nuclear Information System (INIS)

    Fifty-one high-field MR imaging studies (1.5 T, General Electric Signa) of the spinal cord were performed in 42 patients (27 female, 15 male; mean age, 40 years) with clinically definitive (n = 34) or probable (n = 8) multiple sclerosis and suspected spinal cord lesions. MR imaging showed focal spinal cord abnormalities in 38 (75%) of 51 studies. T2-weighted images were abnormal (showing foci of high signal intensity) in 38 studies, T1-weighted images were abnormal (showing areas of low signal intensity or mass effect) in 16 (42%) of 38, and GRASS images were abnormal (showing foci of high signal intensity) in 9 (82%) of 11 cases. Brain MR imaging showed periventricular lesions typical of multiple sclerosis in 34 (81%) of 42 studies. Spinal cord studies were positive in eight cases with normal brain MR images, and brain studies were positive in 13 instances of normal spinal cord MR images. Four lesions were at the cervicomedullary junction, 44 in the cervical spinal cord, and three in the thoracic cord. Mass effect in cord lesions, simulating neoplasm, was seen in seven patients during the acute symptomatic phase. Serial studies in three patients with decreasing symptoms showed a reduction after 3-4 weeks and resolution of the mass effect after 2-6 months

  12. An unusual cause for recurrent chest infections.

    LENUS (Irish Health Repository)

    Lobo, Ronstan

    2012-10-01

    We present a case of an elderly non-smoking gentleman who, since 2005, had been admitted multiple times for recurrent episodes of shortness of breath, wheeze, cough and sputum. The patient was treated as exacerbations of chronic obstructive pulmonary disease (COPD) and\\/or lower respiratory tract infections. Bronchoscopy was done which revealed multiple hard nodules in the trachea and bronchi with posterior tracheal wall sparing. Biopsies confirmed this as tracheopathia osteochondroplastica (TO). He had increasing frequency of admission due to methicillin-resistant Staphylococcus aureus and pseudomonas infections, which failed to clear despite intravenous, prolonged oral and nebulised antibiotics. The patient developed increasing respiratory distress and respiratory failure. The patient died peacefully in 2012. This case report highlights the typical pathological and radiological findings of TO and the pitfalls of misdiagnosing patients with recurrent chest infections as COPD.

  13. Relevance of an incidental chest finding

    Science.gov (United States)

    Cortés-Télles, Arturo; Mendoza, Daniel

    2012-01-01

    Solitary pulmonary nodule represents 0.2% of incidental findings in routine chest X-ray images. One of the main diagnoses includes lung cancer in which small-cell subtype has a poor survival rate. Recently, a new classification has been proposed including the very limited disease stage (VLD stage) or T1-T2N0M0 with better survival rate, specifically in those patients who are treated with surgery. However, current recommendations postulate that surgery remains controversial as a first-line treatment in this stage. We present the case of a 46-year-old female referred to our hospital with a preoperative diagnosis of a solitary pulmonary nodule. On initial approach, a biopsy revealed a small cell lung cancer. She received multimodal therapy with surgery, chemotherapy, and prophylactic cranial irradiation and is currently alive without recurrence on a 2-year follow-up. PMID:22345914

  14. Pleural fluids associated with chest infection.

    Science.gov (United States)

    Quadri, Amal; Thomson, Anne H

    2002-12-01

    Pleural effusions are commonly associated with pneumonias and a small number of these progress to empyema. An understanding of the physiology and pathophysiology of pleural fluid aids the clinician in the management of empyema. There remains much debate about the optimal treatment of empyema in children. Early recognition of the condition is important since delayed therapy may result in unnecessary morbidity. Conventional management with high dose parenteral antibiotics and chest tube drainage remains the mainstay of therapy. However, this treatment modality may fail if the pleural fluid becomes viscous and loculated and, therefore, a more aggressive approach is required. Intrapleural fibrinolytic therapy has been shown to decrease the length of hospital stay and may reduce the need for surgical intervention. The prognosis in children with parapneumonic empyema is excellent with the vast majority retaining normal lung function at long term follow-up.

  15. Digital luminescence radiography of the chest

    International Nuclear Information System (INIS)

    The aim of the present study was to evaluate the efficacy of a digital system in chest radiology compared to the conventional film-screen system. The first studies (1-3) were purely clinical, had two parts, one clinical and one using phantoms, and the 5:th used solely phantoms. Except for the first - pilot - study, the studies were performed as receiver operating characteristic (ROC) analysis. From one exposure, two digital radiographs were obtained, one simulating the film-screen radiograph and one enhanced, using an unsharp mask. The conventional radiograph was compared to this double-image, but in addition to this, even to the simulated normal and enhanced separately (1-3). To evaluate the value of inverted (positive) radiographs, the original digital (negative) radiographs were inverted, and then compared to the originals (4). As digitzation means easy storing and transfer of data and possibility of electronic display, the diagnostic performance of an interactive workstation was assessed (5). In the clinical studies, a variety of chest affections were used: atelectasis, tumor, pneumothorax, fibrosis, mediastinal and bony changes, tuberculosis, incompensations and enlargement of the heart (1), pneumothorax (2), fibrosis (3), and tumor (4). In the phantom studies, test objects simulating tumors (4) and pneumothorax (5) were used. In no study was statistical significant difference seen between the digital and conventional system (p>0.05). Neither in the clinical nor the phantom study did inversion of the radiographs improve diagnostic performance. The workstation performed almost equally well as the radiographs even with a resolution of 1.25 1p/mm compared to the digital radiographs 2.5 and film-screen radiographs 5 1p/mm. (au) (50 refs.)

  16. Clinical assessment of chest pain and guidelines for imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gruettner, J., E-mail: joachim.gruettner@umm.de [1st Department of Medicine (Cardiology), University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim (Germany); Henzler, T. [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim (Germany); Sueselbeck, T. [1st Department of Medicine (Cardiology), University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim (Germany); Fink, C. [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim (Germany); Borggrefe, M.; Walter, T. [1st Department of Medicine (Cardiology), University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim (Germany)

    2012-12-15

    For many emergency facilities, risk assessment of patients with diffuse chest pain still poses a major challenge. In their currently valid recommendations, the international cardiological societies have defined a standardized assessment of the prognostically relevant cardiac risk criteria. Here the classic sequence of basic cardiac diagnostics including case history (cardiac risk factors), physical examination (haemodynamic and respiratory vital parameters), ECG (ST segment analysis) and laboratory risk markers (troponin levels) is paramount. The focus is, on the one hand, on timely indication for percutaneous catheterization, especially in patients at high cardiac risk with or without ST-segment elevation in the ECG, and, on the other hand, on the possibility of safely discharging patients with intermediate or low cardiac risk after non-invasive exclusion of a coronary syndrome. For patients in the intermediate or low risk group, physical or pharmacological stress testing in combination with scintigraphy, echocardiography or magnetic resonance imaging is recommended in addition to basic diagnostics. Moreover, the importance of non-invasive coronary imaging, primarily cardiac CT angiography (CCTA), is increasing. Current data show that in intermediate or low risk patients this method is suitable to reliably rule out coronary heart disease. In addition, attention is paid to the major differential diagnoses of acute coronary syndrome, particularly pulmonary embolism and aortic dissection. Here the diagnostic method of choice is thoracic CT, possibly also in combination with CCTA aiming at a triple rule-out.

  17. Clinical assessment of chest pain and guidelines for imaging

    International Nuclear Information System (INIS)

    For many emergency facilities, risk assessment of patients with diffuse chest pain still poses a major challenge. In their currently valid recommendations, the international cardiological societies have defined a standardized assessment of the prognostically relevant cardiac risk criteria. Here the classic sequence of basic cardiac diagnostics including case history (cardiac risk factors), physical examination (haemodynamic and respiratory vital parameters), ECG (ST segment analysis) and laboratory risk markers (troponin levels) is paramount. The focus is, on the one hand, on timely indication for percutaneous catheterization, especially in patients at high cardiac risk with or without ST-segment elevation in the ECG, and, on the other hand, on the possibility of safely discharging patients with intermediate or low cardiac risk after non-invasive exclusion of a coronary syndrome. For patients in the intermediate or low risk group, physical or pharmacological stress testing in combination with scintigraphy, echocardiography or magnetic resonance imaging is recommended in addition to basic diagnostics. Moreover, the importance of non-invasive coronary imaging, primarily cardiac CT angiography (CCTA), is increasing. Current data show that in intermediate or low risk patients this method is suitable to reliably rule out coronary heart disease. In addition, attention is paid to the major differential diagnoses of acute coronary syndrome, particularly pulmonary embolism and aortic dissection. Here the diagnostic method of choice is thoracic CT, possibly also in combination with CCTA aiming at a triple rule-out.

  18. Control and data acquisition systems for high field superconducting wigglers

    CERN Document Server

    Batrakov, A; Karpov, G; Kozak, V; Kuzin, M; Kuper, E; Mamkin, V; Mezentsev, N A; Repkov, V V; Selivanov, A; Shkaruba, V A

    2001-01-01

    This paper describes the control and DAQ system of superconducting wigglers with magnetic field range up to 10.3 T. The first version of the system controls a 7 T superconducting wiggler prepared for installation at Bessy-II (Germany). The second one controls a 10 T wiggler which is under testing now at the SPring-8 site (Japan). Both systems are based on VME apparatus. The set of specialized VME modules is elaborated to arrange wiggler power supply control, full time wiggler monitoring, and magnetic field high accuracy measurement and field stabilization. The software for the control of the wigglers is written in C language for VxWorks operation system for a Motorola-162 VME controller. The task initialization, stops and acquisition of the data can be done from the nearest personal computer (FTP host for VME), or from the remote system as well.

  19. Diagnostic relevance of high field MRI in clinical neuroradiology: the advantages and challenges of driving a sports car

    International Nuclear Information System (INIS)

    High field MRI operating at 3 T is increasingly being used in the field of neuroradiology on the grounds that higher magnetic field strength should theoretically lead to a higher diagnostic accuracy in the diagnosis of several disease entities. This Editorial discusses the exhaustive review by Wardlaw and colleagues of research comparing 3 T MRI with 1.5 T MRI in the field of neuroradiology. Interestingly, the authors found no convincing evidence of improved image quality, diagnostic accuracy, or reduced total examination times using 3 T MRI instead of 1.5 T MRI. These findings are highly relevant since a new generation of high field MRI systems operating at 7 T has recently been introduced. (orig.)

  20. Diagnostic relevance of high field MRI in clinical neuroradiology: the advantages and challenges of driving a sports car

    Energy Technology Data Exchange (ETDEWEB)

    Wattjes, Mike P.; Barkhof, Frederik [VU University Medical Center, Department of Radiology, Amsterdam (Netherlands)

    2012-11-15

    High field MRI operating at 3 T is increasingly being used in the field of neuroradiology on the grounds that higher magnetic field strength should theoretically lead to a higher diagnostic accuracy in the diagnosis of several disease entities. This Editorial discusses the exhaustive review by Wardlaw and colleagues of research comparing 3 T MRI with 1.5 T MRI in the field of neuroradiology. Interestingly, the authors found no convincing evidence of improved image quality, diagnostic accuracy, or reduced total examination times using 3 T MRI instead of 1.5 T MRI. These findings are highly relevant since a new generation of high field MRI systems operating at 7 T has recently been introduced. (orig.)

  1. Coping in Chest Pain Patients with and without Psychiatric Disorders.

    Science.gov (United States)

    Vitaliano, Peter P.; And Others

    1989-01-01

    Examined relations between psychiatric disorder and coronary heart disease (CHD) in 77 patients with chest pain, and compared coping profiles of chest pain patients with and without psychiatric disorders and CHD. Psychiatric patients with no medical disease were also studied. Results are discussed in the context of illness behavior and…

  2. Low dose computed tomography of the chest : Applications and limitations

    NARCIS (Netherlands)

    Gietema, H.A.

    2007-01-01

    In areas with a high intrinsic contrast such as the chest, radiation dose can be reduced for specific indications. Low dose chest CT is feasible and cannot only be applied for lung cancer screening, but also in daily routine and for early detection of lung destruction. We showed in a small sample of

  3. Segmentation of anatomical structures in chest CT scans

    NARCIS (Netherlands)

    van Rikxoort, E.M.

    2009-01-01

    In this thesis, methods are described for the automatic segmentation of anatomical structures from chest CT scans. First, a method to segment the lungs from chest CT scans is presented. Standard lung segmentation algorithms rely on large attenuation differences between the lungs and the surrounding

  4. Chest physical therapy in acute viral bronchiolitis: an updated review.

    Science.gov (United States)

    Postiaux, Guy; Zwaenepoel, Bruno; Louis, Jacques

    2013-09-01

    We describe the various therapies for infant acute viral bronchiolitis and the contradictory results obtained with chest physical therapy. The treatment target is bronchial obstruction, which is a multifactorial phenomenon that includes edema, bronchoconstriction, and increased mucus production, with a clinical grading defined as severe, moderate, or mild. Chest physical therapy is revisited in its various modalities, according to preliminary scoring of the disease.

  5. Effect of rib-cage structure on acoustic chest impedance

    DEFF Research Database (Denmark)

    Zimmermann, Niels Henrik; Møller, Henrik; Hansen, John;

    2011-01-01

    When a stethoscope is placed on the surface of the chest, the coupler picks up sound from heart and lungs transmitted through the tissues of the ribcage and from the surface of the skin. If the acoustic impedance of the chest surface is known, it is possible to optimize the coupler for picking up...

  6. Giant pericardial cyst mimicking dextrocardia on chest X-ray.

    Science.gov (United States)

    Hamad, Hamad M; Galrinho, Ana; Abreu, João; Valente, Bruno; Bakero, Luis; Ferreira, Rui C

    2013-01-01

    Pericardial cysts are rare benign congenital malformations, usually small, asymptomatic and detected incidentally on chest X-ray as a mass located in the right costophrenic angle. Giant pericardial cysts are very uncommon and produce symptoms by compressing adjacent structures. In this report, the authors present a case of a symptomatic giant pericardial cyst incorrectly diagnosed as dextrocardia on chest X-ray.

  7. Lung mass, right upper lung - chest x-ray (image)

    Science.gov (United States)

    This picture is a chest x-ray of a person with a lung mass. This is a front view, where the lungs are the two dark areas and ... visible in the middle of the chest. The x-ray shows a mass in the right upper lung, ...

  8. Sexual, Physical, Verbal/Emotional Abuse and Unexplained Chest Pain

    Science.gov (United States)

    Eslick, Guy D.; Koloski, Natasha A.; Talley, Nicholas J.

    2011-01-01

    Objectives: Approximately one third of patients with non cardiac chest pain (NCCP) report a history of abuse, however no data exists on the prevalence of abuse among people with unexplained chest pain in the general population. We aimed to determine if there is a relationship between childhood sexual, physical, emotional abuse and unexplained…

  9. Resuscitation, prolonged cardiac arrest, and an automated chest compression device

    DEFF Research Database (Denmark)

    Risom, Martin; Jørgensen, Henrik; Rasmussen, Lars S;

    2010-01-01

    The European Resuscitation Council's 2005 guidelines for cardiopulmonary resuscitation (CPR) emphasize the delivery of uninterrupted chest compressions of adequate depth during cardiac arrest.......The European Resuscitation Council's 2005 guidelines for cardiopulmonary resuscitation (CPR) emphasize the delivery of uninterrupted chest compressions of adequate depth during cardiac arrest....

  10. Management of chest drainage tubes after lung surgery.

    Science.gov (United States)

    Satoh, Yukitoshi

    2016-06-01

    Since chest tubes have been routinely used to drain the pleural space, particularly after lung surgery, the management of chest tubes is considered to be essential for the thoracic surgeon. The pleural drainage system requires effective drainage, suction, and water-sealing. Another key point of chest tube management is that a water seal is considered to be superior to suction for most air leaks. Nowadays, the most common pleural drainage device attached to the chest tube is the three-bottle system. An electronic chest drainage system has been developed that is effective in standardizing the postoperative management of chest tubes. More liberal use of digital drainage devices in the postoperative management of the pleural space is warranted. The removal of chest tubes is a common procedure occurring almost daily in hospitals throughout the world. Extraction of the tube is usually done at the end of full inspiration or at the end of full expiration. The tube removal technique is not as important as how it is done and the preparation for the procedure. The management of chest tubes must be based on careful observation, the patient's characteristics, and the operative procedures that had been performed. PMID:27048219

  11. Measurement of characteristic leap interval between chest and falsetto registers

    NARCIS (Netherlands)

    Miller, DG; Svec, JG; Schutte, HK

    2002-01-01

    A markedly smaller time constant distinguishes a chest-falsetto leap from the more usual execution of a sung interval by muscular adjustments in the length and tension of the vocal folds. The features of such a chest-falsetto leap are examined in detail with respect to F-0, peak-to-peak amplitude of

  12. High field dynamic nuclear polarization—the renaissance

    OpenAIRE

    Griffin, R. G.; Prisner, T. F.

    2010-01-01

    Sensitivity is a critical issue in NMR spectroscopy, microscopy and imaging, and the factor that often limits the success of various applications. The origin of low sensitivity in NMR is well known to be due to the small magnetic moment of nuclear spins, which yields small Boltzmann polarizations and weak absorption signals. Historically, each advance in technology and methodology that has increased the signal-to-noise in NMR has shifted the boundary of what is achievable, often opening new a...

  13. High-field phase-diagram of Fe arsenide superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Y.J.; Jaroszynski, J.; Yamamoto, A.; Gurevich, A.; Riggs, S.C.; Boebinger, G.S.; Larbalestier, D. [National High Magnetic Field Laboratory, Florida State University, Tallahassee-FL 32310 (United States); Wen, H.H. [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Zhigadlo, N.D.; Katrych, S.; Bukowski, Z.; Karpinski, J. [Laboratory for Solid State Physics, ETH Zuerich, CH-8093 Zuerich (Switzerland); Liu, R.H.; Chen, H.; Chen, X.H. [Hefei National Laboratory for Physical Science a Microscale and Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Balicas, L., E-mail: balicas@magnet.fsu.ed [National High Magnetic Field Laboratory, Florida State University, Tallahassee-FL 32310 (United States)

    2009-05-01

    Here, we report an overview of the phase-diagram of single-layered and double-layered Fe arsenide superconductors at high magnetic fields. Our systematic magneto-transport measurements of polycrystalline SmFeAsO{sub 1-x}F{sub x} at different doping levels confirm the upward curvature of the upper critical magnetic field H{sub c2}(T) as a function of temperature T defining the phase boundary between the superconducting and metallic states for crystallites with the ab planes oriented nearly perpendicular to the magnetic field. We further show from measurements on single-crystals that this feature, which was interpreted in terms of the existence of two superconducting gaps, is ubiquitous among both series of single- and double-layered compounds. In all compounds explored by us the zero temperature upper critical field H{sub c2}(0), estimated either through the Ginzburg-Landau or the Werthamer-Helfand-Hohenberg single gap theories, strongly surpasses the weak-coupling Pauli paramagnetic limiting field. This clearly indicates the strong-coupling nature of the superconducting state and the importance of magnetic correlations for these materials. Our measurements indicate that the superconducting anisotropy, as estimated through the ratio of the effective masses gamma = (m{sub c}/m{sub ab}){sup 1/2} for carriers moving along the c-axis and the ab-planes, respectively, is relatively modest as compared to the high-T{sub c} cuprates, but it is temperature, field and even doping dependent. Finally, our preliminary estimations of the irreversibility field H{sub m}(T), separating the vortex-solid from the vortex-liquid phase in the single-layered compounds, indicates that it is well described by the melting of a vortex lattice in a moderately anisotropic uniaxial superconductor.

  14. Superconductivity and the high-field ordered phase in the heavy-fermion compound PrOs4Sb12

    International Nuclear Information System (INIS)

    Superconductivity is observed in the filled skutterudite compound PrOs4Sb12 below a critical temperature Tc = 1.85 K and appears to develop out of a nonmagnetic heavy Fermi liquid with an effective mass m* ∼ 50 me, where me is the free electron mass. Features associated with a cubic crystalline electric field are present in magnetic susceptibility, specific heat, electrical resistivity, and inelastic neutron scattering measurements, yielding a Pr3+ energy level scheme consisting of a Γ3 nonmagnetic doublet ground state, a low-lying Γ5 triplet excited state at ∼10 K, and Γ4 triplet and Γ1 singlet excited states at much higher temperatures. Measurements also indicate that the superconducting state is unconventional and consists of two distinct superconducting phases. At high fields and low temperatures, an ordered phase of magnetic or quadrupolar origin is observed, suggesting that the superconductivity may occur in the vicinity of a magnetic or quadrupolar quantum critical point

  15. Electronic versus traditional chest tube drainage following lobectomy

    DEFF Research Database (Denmark)

    Lijkendijk, Marike; Licht, Peter B; Neckelmann, Kirsten

    2015-01-01

    OBJECTIVES: Electronic drainage systems have shown superiority compared with traditional (water seal) drainage systems following lung resections, but the number of studies is limited. As part of a medico-technical evaluation, before change of practice to electronic drainage systems for routine...... thoracic surgery, we conducted a randomized controlled trial (RCT) investigating chest tube duration and length of hospitalization. METHODS: Patients undergoing lobectomy were included in a prospective open label RCT. A strict algorithm was designed for early chest tube removal, and this decision...... time for chest tube removal, as well as length of hospitalization. RESULTS: A total of 105 patients were randomized. We found no significant difference between the electronic group and traditional group in optimal chest tube duration (HR = 0.83; 95% CI: 0.55-1.25; P = 0.367), actual chest tube duration...

  16. Pioneering Structural Solutions for Compact High Field Experiments Developed for the Alcator and the Ignitor Programs

    Science.gov (United States)

    Salvetti, M.; Coppi, B.

    2015-11-01

    Recently there has been an increased awareness of the fact that the line of research based on compact high field machines is the most promising to approach ignition conditions in DT burning plasmas and has acquired new perspectives for its applications. Then the technological solutions that have made these machines possible have become subject to new attention and, in some cases, to rediscovery. The Alcator Program and, followed by Ignitor Program, has led to invent the coupled air-core former poloidal field system that has made compact machine possible and has been adopted on all advanced toroidal machines that came after Alcator. A recently rediscovered solution aimed at reducing the mechanical stresses in the inner legs of the toroidal magnet coils is the ``Upper and Lower Bracing Rings'' system that has had a key role in the design of the Ignitor machine and its evolution. Another solution to minimize the machine dimensions while maintaining high toroidal fields, in order to achieve high plasma current densities, is that of ``bucking and wedging'' of the toroidal magnet by coupling it mechanically to the central solenoid. Sponsored in part by the U.S. DoE.

  17. Nitrogen detected TROSY at high field yields high resolution and sensitivity for protein NMR

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, Koh [National Institute for Advanced Industrial Science and Technology, Molecular Profiling Research Center for Drug Discovery (Japan); Arthanari, Haribabu [Harvard Medical School, Department of Biochemistry and Molecular Pharmacology (United States); Shimada, Ichio, E-mail: shimada@iw-nmr.f.u-tokyo.ac.jp [National Institute for Advanced Industrial Science and Technology, Molecular Profiling Research Center for Drug Discovery (Japan); Wagner, Gerhard, E-mail: gerhard-wagner@hms.harvard.edu [Harvard Medical School, Department of Biochemistry and Molecular Pharmacology (United States)

    2015-12-15

    Detection of {sup 15}N in multidimensional NMR experiments of proteins has sparsely been utilized because of the low gyromagnetic ratio (γ) of nitrogen and the presumed low sensitivity of such experiments. Here we show that selecting the TROSY components of proton-attached {sup 15}N nuclei (TROSY {sup 15}N{sub H}) yields high quality spectra in high field magnets (>600 MHz) by taking advantage of the slow {sup 15}N transverse relaxation and compensating for the inherently low {sup 15}N sensitivity. The {sup 15}N TROSY transverse relaxation rates increase modestly with molecular weight but the TROSY gain in peak heights depends strongly on the magnetic field strength. Theoretical simulations predict that the narrowest line width for the TROSY {sup 15}N{sub H} component can be obtained at 900 MHz, but sensitivity reaches its maximum around 1.2 GHz. Based on these considerations, a {sup 15}N-detected 2D {sup 1}H–{sup 15}N TROSY-HSQC ({sup 15}N-detected TROSY-HSQC) experiment was developed and high-quality 2D spectra were recorded at 800 MHz in 2 h for 1 mM maltose-binding protein at 278 K (τ{sub c} ∼ 40 ns). Unlike for {sup 1}H detected TROSY, deuteration is not mandatory to benefit {sup 15}N detected TROSY due to reduced dipolar broadening, which facilitates studies of proteins that cannot be deuterated, especially in cases where production requires eukaryotic expression systems. The option of recording {sup 15}N TROSY of proteins expressed in H{sub 2}O media also alleviates the problem of incomplete amide proton back exchange, which often hampers the detection of amide groups in the core of large molecular weight proteins that are expressed in D{sub 2}O culture media and cannot be refolded for amide back exchange. These results illustrate the potential of {sup 15}N{sub H}-detected TROSY experiments as a means to exploit the high resolution offered by high field magnets near and above 1 GHz.

  18. ADX: a high field, high power density, advanced divertor and RF tokamak

    Science.gov (United States)

    LaBombard, B.; Marmar, E.; Irby, J.; Terry, J. L.; Vieira, R.; Wallace, G.; Whyte, D. G.; Wolfe, S.; Wukitch, S.; Baek, S.; Beck, W.; Bonoli, P.; Brunner, D.; Doody, J.; Ellis, R.; Ernst, D.; Fiore, C.; Freidberg, J. P.; Golfinopoulos, T.; Granetz, R.; Greenwald, M.; Hartwig, Z. S.; Hubbard, A.; Hughes, J. W.; Hutchinson, I. H.; Kessel, C.; Kotschenreuther, M.; Leccacorvi, R.; Lin, Y.; Lipschultz, B.; Mahajan, S.; Minervini, J.; Mumgaard, R.; Nygren, R.; Parker, R.; Poli, F.; Porkolab, M.; Reinke, M. L.; Rice, J.; Rognlien, T.; Rowan, W.; Shiraiwa, S.; Terry, D.; Theiler, C.; Titus, P.; Umansky, M.; Valanju, P.; Walk, J.; White, A.; Wilson, J. R.; Wright, G.; Zweben, S. J.

    2015-05-01

    The MIT Plasma Science and Fusion Center and collaborators are proposing a high-performance Advanced Divertor and RF tokamak eXperiment (ADX)—a tokamak specifically designed to address critical gaps in the world fusion research programme on the pathway to next-step devices: fusion nuclear science facility (FNSF), fusion pilot plant (FPP) and/or demonstration power plant (DEMO). This high-field (⩾6.5 T, 1.5 MA), high power density facility (P/S ˜ 1.5 MW m-2) will test innovative divertor ideas, including an ‘X-point target divertor’ concept, at the required performance parameters—reactor-level boundary plasma pressures, magnetic field strengths and parallel heat flux densities entering into the divertor region—while simultaneously producing high-performance core plasma conditions that are prototypical of a reactor: equilibrated and strongly coupled electrons and ions, regimes with low or no torque, and no fuelling from external heating and current drive systems. Equally important, the experimental platform will test innovative concepts for lower hybrid current drive and ion cyclotron range of frequency actuators with the unprecedented ability to deploy launch structures both on the low-magnetic-field side and the high-magnetic-field side—the latter being a location where energetic plasma-material interactions can be controlled and favourable RF wave physics leads to efficient current drive, current profile control, heating and flow drive. This triple combination—advanced divertors, advanced RF actuators, reactor-prototypical core plasma conditions—will enable ADX to explore enhanced core confinement physics, such as made possible by reversed central shear, using only the types of external drive systems that are considered viable for a fusion power plant. Such an integrated demonstration of high-performance core-divertor operation with steady-state sustainment would pave the way towards an attractive pilot plant, as envisioned in the ARC concept

  19. Diffuse axonal injury at ultra-high field MRI.

    Directory of Open Access Journals (Sweden)

    Christoph Moenninghoff

    Full Text Available Diffuse axonal injury (DAI is a specific type of traumatic brain injury caused by shearing forces leading to widespread tearing of axons and small vessels. Traumatic microbleeds (TMBs are regarded as a radiological marker for DAI. This study aims to compare DAI-associated TMBs at 3 Tesla (T and 7 T susceptibility weighted imaging (SWI to evaluate possible diagnostic benefits of ultra-high field (UHF MRI.10 study participants (4 male, 6 female, age range 20-74 years with known DAI were included. All MR exams were performed with a 3 T MR system (Magnetom Skyra and a 7 T MR research system (Magnetom 7 T, Siemens AG, Healthcare Sector, Erlangen, Germany each in combination with a 32-channel-receive coil. The average time interval between trauma and imaging was 22 months. Location and count of TMBs were independently evaluated by two neuroradiologists on 3 T and 7 T SWI images with similar and additionally increased spatial resolution at 7 T. Inter- and intraobserver reliability was assessed using the interclass correlation coefficient (ICC. Count and diameter of TMB were evaluated with Wilcoxon signed rank test.Susceptibility weighted imaging revealed a total of 485 TMBs (range 1-190, median 25 at 3 T, 584 TMBs (plus 20%, range 1-262, median 30.5 at 7 T with similar spatial resolution, and 684 TMBs (plus 41%, range 1-288, median 39.5 at 7 T with 10-times higher spatial resolution. Hemorrhagic DAI appeared significantly larger at 7 T compared to 3 T (p = 0.005. Inter- and intraobserver correlation regarding the counted TMB was high and almost equal 3 T and 7 T.7 T SWI improves the depiction of small hemorrhagic DAI compared to 3 T and may be supplementary to lower field strengths for diagnostic in inconclusive or medicolegal cases.

  20. MAGNET

    CERN Multimedia

    Benoit Curé

    The cooling down to the nominal temperature of 4.5 K was achieved at the beginning of August, in conjunction with the completion of the installation work of the connection between the power lines and the coil current leads. The temperature gradient on the first exchanger of the cold box is now kept within the nominal range. A leak of lubricant on a gasket of the helium compressor station installed at the surface was observed and several corrective actions were necessary to bring the situation back to normal. The compressor had to be refilled with lubricant and a regeneration of the filters and adsorbers was necessary. The coil cool down was resumed successfully, and the cryogenics is running since then with all parameters being nominal. Preliminary tests of the 20kA coil power supply were done earlier at full current through the discharge lines into the dump resistors, and with the powering busbars from USC5 to UXC5 without the magnet connected. On Monday evening August 25th, at 8pm, the final commissionin...

  1. MAGNET

    CERN Multimedia

    Benoit Curé

    2013-01-01

    Maintenance work and consolidation activities on the magnet cryogenics and its power distribution are progressing according to the schedules. The manufacturing of the two new helium compressor frame units has started. The frame units support the valves, all the sensors and the compressors with their motors. This activity is subcontracted. The final installation and the commissioning at CERN are scheduled for March–April 2014. The overhauls of existing cryogenics equipment (compressors, motors) are in progress. The reassembly of the components shall start in early 2014. The helium drier, to be installed on the high-pressure helium piping, has been ordered and will be delivered in the first trimester of 2014. The power distribution for the helium compressors in SH5 on the 3.3kV network is progressing. The 3.3kV switches, between each compressor and its hot spare compressor, are being installed, together with the power cables for the new compressors. The 3.3kV electrical switchboards in SE5 will ...

  2. MAGNET

    CERN Multimedia

    B. Curé

    The first phase of the commissioning ended in August by a triggered fast dump at 3T. All parameters were nominal, and the temperature recovery down to 4.5K was carried out in two days by the cryogenics. In September, series of ramps were achieved up to 3 and finally 3.8T, while checking thoroughly the detectors in the forward region, measuring any movement of and around the HF. After the incident of the LHC accelerator on September 19th, corrective actions could be undertaken in the forward region. When all these displacements were fully characterized and repetitive, with no sign of increments in displacement at each field ramp, it was possible to start the CRAFT, Cosmic Run at Four Tesla (which was in fact at 3.8T). The magnet was ramped up to 18.16kA and the 3 week run went smoothly, with only 4 interruptions: due to the VIP visits on 21st October during the LHC inauguration day; a water leak on the cooling demineralized water circuit, about 1 l/min, that triggered a stop of the cooling pumps, and resulte...

  3. High-field magnetotransmission investigation of natural graphite

    OpenAIRE

    Ubrig, N.; Plochocka, P.; Kossacki, P.; Orlita, M.; Maude, D. K.; Portugall, O.; Rikken, G.L.J.A.

    2011-01-01

    Magneto-transmission measurements in magnetic fields in the range B=20-60T have been performed to probe the H and K-point Landau level transitions in natural graphite. At the H-point, two series of transitions, whose energy evolves as $\\sqrt{B}$ are observed. A reduced Slonczewski, Weiss and McClure (SWM) model with only two parameters to describe the intra-layer (gamma0) and inter-layer (gamma1) coupling correctly describes all observed transitions. Polarization resolved measurements confirm...

  4. High-field thermal transports properties of REBCO coated conductors

    CERN Document Server

    Bonura, M

    2015-01-01

    The use of REBCO coated conductors is envisaged for many applications, extending from power cables to high-field magnets. Whatever the case, thermal properties of REBCO tapes play a key role for the stability of superconducting devices. In this work, we present the first study on the longitudinal thermal conductivity (k) of REBCO coated conductors in magnetic fields up to 19 T applied both parallelly and perpendicularly to the thermal-current direction. Copper-stabilized tapes from six industrial manufacturers have been investigated. We show that zero-field k of coated conductors can be calculated with an accuracy of ‡ 15% from the residual resistivity ratio of the stabilizer and the Cu/non-Cu ratio. Measurements performed at high fields have allowed us to evaluate the consistency of the procedures generally used for estimating in-field k in the framework of the Wiedemann-Franz law from an electrical characterization of the materials. In-field data are intended to provide primary ingredients for the ...

  5. Advances in High-Field BOLD fMRI

    Directory of Open Access Journals (Sweden)

    Markus Barth

    2011-11-01

    Full Text Available This review article examines the current state of BOLD fMRI at a high magnetic field strength of 7 Tesla. The following aspects are covered: a short description of the BOLD contrast, spatial and temporal resolution, BOLD sensitivity, localization and spatial specificity, technical challenges as well as an outlook on future developments are given. It is shown that the main technical challenges of performing BOLD fMRI at high magnetic field strengths—namely development of array coils, imaging sequences and parallel imaging reconstruction—have been solved successfully. The combination of these developments has lead to the availability of high-resolution BOLD fMRI protocols that are able to cover the whole brain with a repetition time (TR shorter than 3 s. The structural information available from these high-resolution fMRI images itself is already very detailed, which helps to co-localize structure and function. Potential future applications include whole-brain connectivity analysis on a laminar resolution and single subject examinations.

  6. Spontaneous massive hemothorax secondary to chest wall chondrosarcoma: a case report.

    Science.gov (United States)

    Rad, Mohammad Ghasemi; Mahmodlou, Rahim; Mohammadi, Afshin; Mladkova, Nikol; Noorozinia, Farahnaz

    2011-01-01

    We present the case of a 30-year-old man with no past history of disease or recent trauma, who was seen in the emergency room after developing sharp pain in the left hemithorax. Chest roentgenogram showed costopherenic angle blunting and an oval mass in the left mediastinum. A computed tomographic scan showed extrapleural mass with coarse calcifications and pleural effusion, confirmed by magnetic resonance imaging. The tumor was biopsied and removed during thoracotomy. The pathology reported revealed chondrosarcoma, which is a rare cause for a spontaneous massive hemothorax. Invasion of the intercostals vessels by the tumor was the probable cause of hemothorax in this patient. PMID:21740393

  7. Prospects for the use of HTS in high field magnets for future accelerator facilities

    CERN Document Server

    Ballarino, A

    2014-01-01

    The enthusiasm that followed discovery of High Temperature Superconductors (HTS) and the initial genuine hope of a replacement technology that could have taken over from conventional Low Temperature Superconductors (LTS) was damped during the years by difficulties in reaching performance levels of competing materials: insufficient current-carrying performance, short piece lengths, and fragility of the brittle oxide superconductors made development of applications slow and limited to demonstrators or devices less demanding from the point of view of conductor performance. However, thanks to a continuous R&D effort, significant progress was made in the past years on the development of cuprate superconductors. Today long lengths of BSCCO 2223 (km range) and REBCO (a more general acronym for YBCO, where RE = Rare Earth) tape (hundreds of meters range) conductor with controlled and homogeneous characteristics are commercially available, and tremendous progress has been made in the development of BSSCO 2212 roun...

  8. Development of Cu-Nb alloy microcomposite conductors for high field pulsed magnets. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Pantsyrnyi, V.I.; Shikov, A.K.; Nikulin, A.D.; Belyiakov, N.M.; Potapenko, I.I.; Vorob`ova, A.E.; Silaev, A.G.; Kozlenkova, N.I.; Zinov`ev, V.G.; Drobyshev, V.A. [Vsesoyuznyj Nauchno-Issledovatel`skij Inst. Neorganicheskikh Materialov, Moscow (Russian Federation)

    1995-12-31

    Primary goal is to develop high strength-high conductivity composite wires with enhanced cross section. The following research areas were started: melting, deformation, TEM, SEM, and mechanical/electrical characterization of in-situ Cu-Nb microcomposites. Consumable arc melting using initial composite electrodes produced by cold deformation was chosen for preparing initial ingots of Cu-(16- 18)wt%Nb alloy. The deformation process including extrusion, drawing with intermediate heat treatments, and rolling was analyzed. Structure of Cu-Nb composite was investigated at all stages of its fabrication. Rebundling was successfully used to manufacture conductors with enhanced cross sections. Wire with 3x7mm{sup 2} cross section and 50m length was produced with UTS (20 C) = 1000 MPa and electroconductivity 70% IACS.

  9. High-field functional magnetic resonance imaging of vocalization processing in marmosets

    OpenAIRE

    Sadagopan, Srivatsun; Temiz-Karayol, Nesibe Z.; Henning U. Voss

    2015-01-01

    Vocalizations are behaviorally critical sounds, and this behavioral importance is reflected in the ascending auditory system, where conspecific vocalizations are increasingly over-represented at higher processing stages. Recent evidence suggests that, in macaques, this increasing selectivity for vocalizations might culminate in a cortical region that is densely populated by vocalization-preferring neurons. Such a region might be a critical node in the representation of vocal communication sou...

  10. Niobium-germanium superconducting tapes for high-field magnet applications

    Science.gov (United States)

    Braginski, A. I.; Roland, G. W.; Daniel, M. R.; Woolam, J. A.

    1977-01-01

    A process of fabricating superconducting Nb3Ge tapes by chemical vapor deposition (CVD) has been developed and tapes up to 10 meters long fabricated. The typical properties achieved were: critical temperature T sub c = 20 K, upper critical field H sub c2 = 29 tesla at 4.2 K, and J sub c = 3 to 4 x 10 to the 8th power A m(-2) at 4.2 K, 18 tesla. The relative depression of T sub c and H sub c2 compared with the best thin film samples sputtered on sapphire was due to the presence of Nb5Ge3 second-phase particles used as flux pinning centers and to strains induced by thermal mixmatch with Hastelloy B tape substrates. A peculiar field dependence of flux pinning force that was observed in both CVD and sputtered Nb3Ge indicated a premature pin-breaking mechanism or a phase inhomogeneity. Directions of further optimization work were defined.

  11. Age-related changes in chest geometry during cardiopulmonary resuscitation.

    Science.gov (United States)

    Dean, J M; Koehler, R C; Schleien, C L; Michael, J R; Chantarojanasiri, T; Rogers, M C; Traystman, R J

    1987-06-01

    We studied alterations of chest geometry during conventional cardiopulmonary resuscitation in anesthetized immature swine. Pulsatile force was applied to the sternum in increments to determine the effects of increasing compression on chest geometry and intrathoracic vascular pressures. In 2-wk- and 1-mo-old piglets, permanent changes in chest shape developed due to incomplete recoil of the chest along the anteroposterior axis, and large intrathoracic vascular pressures were generated. In 3-mo-old animals, permanent chest deformity did not develop, and large intrathoracic vascular pressures were not produced. We propose a theoretical model of the chest as an elliptic cylinder. Pulsatile displacement along the minor axis of an ellipse produces a greater decrease in cross-sectional area than displacement of a circular cross section. As thoracic cross section became less circular due to deformity, greater changes in thoracic volume, and hence pressure, were produced. With extreme deformity at high force, pulsatile displacement became limited, diminishing pressure generation. We conclude that changes in chest geometry are important in producing intrathoracic intravascular pressure during conventional cardiopulmonary resuscitation in piglets. PMID:3610916

  12. Measurement of chest wall displacement based on terahertz wave

    Science.gov (United States)

    Li, Hui; Lv, Hao; Jiao, Teng; Lu, Guohua; Li, Sheng; Li, Zhao; Liu, Miao; Jing, Xijing; Wang, Jianqi

    2015-02-01

    Measurement of chest wall displacement is an important approach for measuring mechanics of chest wall, which has considerable significance for assessing respiratory system and diagnosing pulmonary diseases. However, existing optical methods for measuring chest wall displacement are inconvenient for some specific patients such as the female patients and the patients with bandaged chest. In this letter, we proposed a method for measuring chest wall displacement based on terahertz wave and established corresponding mathematic model and set up a terahertz measurement system. The main advantages of this method are that it can measure the chest wall displacement of the subjects without taking off clothes or arranging any markers. To validate this method and assess the performance of the terahertz system, in vitro, the displacement of a water module driven by a linear guide rail was measured by the terahertz system and compared with the actual displacement of the water module. The results showed that the waveforms measured with two methods have a good agreement, and the relative error is less than 5% and sufficiently good for measurement demands. In vivo, the synchronous experiment was performed on five human volunteers with the terahertz system and a respiratory belt transducer. The results demonstrate that this method has good performance and promising prospects for measuring chest wall displacement.

  13. Acquisition and analysis strategies in functional MRI at high fields

    CERN Document Server

    Windischberger, C

    2001-01-01

    Functional magnetic resonance imaging represents a non-invasive technique to examine neuronal activity in the brain. It applies radio waves to excite nuclear spins, using the emitted signal during relaxation for image generation. Signal modulations from local blood flow and oxygenation level changes caused by neuronal activity are the basis for calculating functional brain maps with high spatial resolution. The present work discusses concepts for improving the spatial and temporal resolution, as well as sophisticated analysis approaches. Besides an exhaustive description of image reconstruction algorithms, computational simulations on echo-shifting in echo-planar imaging are presented and effects on spatial resolution are quantified. The results demonstrate that echo-shifting causes only minimal resolution losses for high signal-to-noise data, but leads to severe resolution degradation (up to 30 %) in images with low signal-to-noise ratios. After an overview of the mechanisms that cause fMRI signal changes su...

  14. Dose profile in computed tomography chest scan

    International Nuclear Information System (INIS)

    For the optimization of the patient dose in computed tomography (CT), the Brazilian legislation only established the diagnostic reference levels (DRL's) in terms of Multiple Scan Average Dose (MSAD) in a typical adult as a parameter of quality control of CT scanners. Conformity to the DRL's can be verified by measuring the dose distribution in CT scans and MSAD determination. An analysis of the quality of CT scans of the metropolitan region of Belo Horizonte is necessary by conducting pertinent tests to the study that are presented in the ANVISA (National Agency of Sanitary Vigilance) Guide. The purpose of this study is to investigate, in a chest scan, the variation of dose in CT. To measure the dose profile are used lithium fluoride thermoluminescent dosimeters (TLD-100 Rod) distributed in cylinders positioned in peripheral and central regions of a phantom of polymethylmethacrylate (PMMA). The data obtained allow us to observe the variation of the dose profile inside the phantom. The peripheral region shows higher dose values than the central region. The longitudinal variation can be observed and the maximum dose was recorded at the edges of the phantom (41,58±5,10) mGy at the midpoint of the longitudinal axis. The results will contribute to disseminate the proper procedure and optimize the dosimetry and the tests of quality control in CT, as well as make a critical analysis of the DRL's. (author)

  15. ISR magnet model

    CERN Multimedia

    1965-01-01

    Field measurements being made on the ISR magnet model. In the foreground, the poleface windings can be seen - as distinct from the large exciting coils - together with their supply cables. These windings are mainly used to compensate the saturation effects at high fields. The steel plates forming the yoke are welded together along the whole length of the magnet.

  16. An uncommon cause of chest pain - penetrating atherosclerotic aortic ulcer

    OpenAIRE

    Kyaw, Htoo; Sadiq, Sanah; Chowdhury, Arnab; Gholamrezaee, Rashin; Yoe, Linus

    2016-01-01

    Chest pain is a very common symptom and can be of cardiac or non-cardiac origin. It accounts for approximately 5.5 million annual emergency room visits in the United States, according to 2011 CDC data. Penetrating atherosclerotic aortic ulcer (PAU), an uncommon condition, is also a potential cause of chest pain. We here report the case of a 65-year-old woman who presented with atypical chest and back pain. The pain persisted for 4 weeks necessitating two emergency room visits. Initial tests w...

  17. Chest X-ray in newborns and infants

    International Nuclear Information System (INIS)

    Chest X-ray in newborns and infants shows great differences to that in adults. Therefore all radiologists, who engage in X-rays in this age group, must be familiar with the special features. At the beginning specific items of examination methods are explained, which must be strictly followed due to radiological protection. Focus of the paper is the discussion of the important chest diseases in newborn and infants, which are mostly unknown in chest diagnosis in adults. Many of them can be life-threatening, thus their knowledge is essential. Pathophysiological explanations shall make the special radiological signs understandable. (orig.)

  18. Simultaneous EEG-fMRI at ultra-high field: artifact prevention and safety assessment.

    Science.gov (United States)

    Jorge, João; Grouiller, Frédéric; Ipek, Özlem; Stoermer, Robert; Michel, Christoph M; Figueiredo, Patrícia; van der Zwaag, Wietske; Gruetter, Rolf

    2015-01-15

    The simultaneous recording of scalp electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) can provide unique insights into the dynamics of human brain function, and the increased functional sensitivity offered by ultra-high field fMRI opens exciting perspectives for the future of this multimodal approach. However, simultaneous recordings are susceptible to various types of artifacts, many of which scale with magnetic field strength and can seriously compromise both EEG and fMRI data quality in recordings above 3T. The aim of the present study was to implement and characterize an optimized setup for simultaneous EEG-fMRI in humans at 7 T. The effects of EEG cable length and geometry for signal transmission between the cap and amplifiers were assessed in a phantom model, with specific attention to noise contributions from the MR scanner coldheads. Cable shortening (down to 12 cm from cap to amplifiers) and bundling effectively reduced environment noise by up to 84% in average power and 91% in inter-channel power variability. Subject safety was assessed and confirmed via numerical simulations of RF power distribution and temperature measurements on a phantom model, building on the limited existing literature at ultra-high field. MRI data degradation effects due to the EEG system were characterized via B0 and B1(+) field mapping on a human volunteer, demonstrating important, although not prohibitive, B1 disruption effects. With the optimized setup, simultaneous EEG-fMRI acquisitions were performed on 5 healthy volunteers undergoing two visual paradigms: an eyes-open/eyes-closed task, and a visual evoked potential (VEP) paradigm using reversing-checkerboard stimulation. EEG data exhibited clear occipital alpha modulation and average VEPs, respectively, with concomitant BOLD signal changes. On a single-trial level, alpha power variations could be observed with relative confidence on all trials; VEP detection was more limited, although

  19. Response to the argument on the risk of cancer with chest CT screening. Is low-dose chest CT safe?

    International Nuclear Information System (INIS)

    The steady increase in the annual number of chest CT screening has become a worldwide concern because of its associated risk of lung cancer. Epidemiological studies, however, have shown that repeated exposure to low-dose radiation does not increase the risk of lung cancer. In addition, a recent randomized controlled study on chest CT screening has shown its usefulness for reducing lung cancer mortality. We reviewed the risk of lung cancer after repeated exposure to low-dose radiation, the efficacy of chest CT screening, and device technology for reducing the irradiation dose. (author)

  20. Chest trauma: A case for single lung ventilation

    Directory of Open Access Journals (Sweden)

    Nagaraj Pandharikar

    2016-01-01

    Full Text Available Chest trauma is one of the important causes of mortality and morbidity in pediatric trauma patients. The complexity, magnitude, and type of lung injury make it extremely challenging to provide optimal oxygenation and ventilation while protecting the lung from further injury due to mechanical ventilation. Independent lung ventilation is used sporadically in these patients who do not respond to these conventional ventilatory strategies using double-lumen endotracheal tubes, bronchial blocker balloons, etc. However, this equipment may not be easily available in developing countries, especially for pediatric patients. Here, we present a case of severe chest trauma with pulmonary contusion, flail chest, and bronchopleural fistula, who did not respond to conventional lung protective strategies. She was successfully managed with bronchoscopy-guided unilateral placement of conventional endotracheal tube followed by single lung ventilation leading to resolution of a chest injury.

  1. Evaluation of different imaging chains in clinical chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Manninen, H.; Terho, E.O.; Wiljasalo, M.; Wiljasalo, S.; Soimakallio, S. (Kuopio Central Hospital (Finland))

    1984-11-01

    Six imaging techniques in clinical chest radiography have been evaluated: four film-screen combinations in the conventional grid technique and two combinations in the air gap technique. Five parameters characterising the quality of a chest radiograph were evaluated by three radiologists and one chest physician by using a nominal grading scale from -2 to +2 compared with the standard technique. The quality parameters judged were: the visibility of peripheral lung vessels, lung parenchyme, the pulmonary hilum, and lung structure behind the heart shadow, as well as the visibility of miscellaneous findings of clinical interest. The air gap technique was shown to be superior to the ordinary grid technique. The diagnostic quality of chest radiography does not necessarily deteriorate with the screen speed. However, statistically significant differences were noticed, even between techniques which had equal speed and physical resolution.

  2. Thoracoscopic pulmonary wedge resection without post-operative chest drain

    DEFF Research Database (Denmark)

    Holbek, Bo Laksáfoss; Hansen, Henrik Jessen; Kehlet, Henrik;

    2016-01-01

    effusion and coagulopathy. Chest X-rays were done twice on the day of surgery. 30-day complications were compiled from patient records. RESULTS: 49 patients underwent 51 unilateral VATS wedge resections without using a post-operative chest drain. No patient required reinsertion of a chest drain. 30 (59...... %) patients had a pneumothorax of mean size 12 ± 12 mm on supine 8-h post-operative X-ray for which the majority resolved spontaneously within 2-week control. There were no complications on 30-day follow-up. Median length of stay was 1 day. CONCLUSIONS: The results support that VATS wedge resection...... for pulmonary nodules without a post-operative chest drain may be safe in a selected group of patients....

  3. Chest X ray examination of workers exposed to pneumoconiosis risk

    International Nuclear Information System (INIS)

    Chest X-ray examination of workers exposed to pneumoconiosis risk: critical analysis of legal and radiation protection aspects. Chest X-ray examination is one of the most common radiological examinations practised in Italy. According to Presidential Decree 1124/65, workers exposed to risk of asbestosis and silicosis must undergo a chest radiography once a year, on occasion of the periodic medical examination. Basic requirements aimed at the radiation protection of the patient must therefore be complied with, and optimization of the chest radiography execution procedures is required. This paper illustrates the results obtained with the implementation of the NEXT programme in Italy for this kind of X-ray examination. The main objective of the NEXT programme is the optimization of radiological techniques. On the basis of the most recent publications in the field of radiation protection, a critical analysis is made of the laws in force in Italy

  4. Radiological chest manifestations in diffuse infiltrative lymphocytosis syndrome (DILS

    Directory of Open Access Journals (Sweden)

    F Ismail

    2011-06-01

    Full Text Available This report focuses on the radiological manifestations of diffuse interstitial lymphocytosis syndrome (DILS in the chest. Awareness of this entity and early diagnosis by radiologists will enable timeous intervention by clinicians.

  5. The chest pain center in the emergency department.

    Science.gov (United States)

    Zalenski, R J; Grzybowski, M

    2001-05-01

    Despite the improvement of medical treatment for acute coronary syndromes throughout the 20th century, the authors believe that many cases of life-threatening coronary events could be avoided through early detection of CAD and the use of preventive strategies. Establishing chest pain units that are linked to the ED is one excellent strategy to risk-stratify patients with symptoms who are at risk for sustaining an AMI or having lethal arrhythmias. There is a need for more research on chest pain units to determine the value for cost and to further optimize strategies for ACI detection and screening. In EDs with high volumes of chest pain patients, or high pressures to avoid hospital admissions, a planned, systematic, and rapid approach to the treatment of AMI and the diagnosis of chest pain is a rewarding necessity. PMID:11373990

  6. Radiology of chest diseases. 3. tot. rev. and upd. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Lange, S. [Knappschaftshospital Recklinghausen (Germany). Dept. of Radiology; Walsh, G. [Royal Berkshire Hospital, Reading (United Kingdom). Dept. of Radiology

    2007-07-01

    Almost a decade has passed since the publication of the second edition of Radiology of Chest Diseases in 1997. This period has seen tremendous advances in imaging technology. Single-slice helical CT has given way to multi-detector row CT (MDCT), and with increasing numbers of detectors we move toward the concept of 'isotropic' spatial resolution. This has been combined with decreased scan times and improved temporal resolution. The rapid evolution of CT technology has led to marked improvements in the quality of thoracic CT studies and has allowed us to contemplate and perform with some success cardiac evaluation and CT coronary angiography. Positron emission tomography (PET)/PET-CT has been incorporated into everyday clinical practice in the past decade and today plays a significant role in imagin evaluation of thoracic disease, particularly in oncologic staging and assessment. Advances in magnetic resonance imaging (MRI) today allow improved cardiac evaluation and particularly myocardial first-pass perfusion and viability assessment. In this text, we have tried to convey how these exciting advances in technology fit into the clinical setting of cardiothoracic imaging evaluation. We also recognize the ever-increasing availability and use of CT as an 'early' second-line imaging tool in assessment of the patient with suspected pulmonary disease and have placed a greater emphasis on the role of high-resolution/thin-section CT in evaluation of parenchymal lung disease. A new chapter on interventional procedures in the thorax describes a spectrum of procedures from the standard image-guided biopsy and drainage through to the more specialized interventions of pulmonary AVM and pulmonary false aneurysm embolization. Once again, we hope that this text conveys the fascinating diversity of cardiothoracic radiology and that it will prove a useful guide to the practitioner in the every-day clinical setting. (orig.)

  7. Histiocytic disorders of the chest: imaging findings.

    Science.gov (United States)

    Ahuja, Jitesh; Kanne, Jeffrey P; Meyer, Cristopher A; Pipavath, Sudhakar N J; Schmidt, Rodney A; Swanson, Jonathan O; Godwin, J David

    2015-01-01

    Histiocytic disorders of the chest comprise a broad spectrum of diseases. The lungs may be involved in isolation or as part of systemic disease. Some of these disorders are primary and have unknown etiology, and others result from a histiocytic response to a known cause. Among primary histiocytic disorders, pulmonary Langerhans cell histiocytosis (PLCH) is the most common; others include Erdheim-Chester disease and Rosai-Dorfman disease. Adult PLCH occurs almost exclusively in adults aged 20-40 years who smoke. Pediatric PLCH is extremely rare and typically occurs as part of multisystemic disease. Erdheim-Chester disease affects middle-aged and older adults; thoracic involvement usually occurs as part of systemic disease. Rosai-Dorfman disease affects children and young adults and manifests as painless cervical lymphadenopathy. Examples of secondary histiocytic disorders are storage diseases such as Gaucher disease, Niemann-Pick disease, and Fabry disease; pneumoconiosis such as silicosis and coal workers' pneumoconiosis; and infections such as Whipple disease and malakoplakia. These disorders are characterized at histopathologic examination on the basis of infiltration of alveoli or the pulmonary interstitium by histiocytes, which are a group of cells that includes macrophages and dendritic cells. Dendritic cells are a heterogeneous group of nonphagocytic antigen-presenting immune cells. Immunohistochemical markers help to distinguish among various primary histiocytic disorders. Characteristic radiologic findings in the appropriate clinical context may obviate biopsy to establish a correct diagnosis. However, in the absence of these findings, integration of clinical, pathologic, and radiologic features is required to establish a diagnosis. PMID:25763722

  8. High-Frequency Chest Compression: A Summary of the Literature

    OpenAIRE

    Dosman, Cara F; Jones, Richard L

    2005-01-01

    The purpose of the present literature summary is to describe high-frequency chest compression (HFCC), summarize its history and outline study results on its effect on mucolysis, mucus transport, pulmonary function and quality of life. HFCC is a mechanical method of self-administered chest physiotherapy, which induces rapid air movement in and out of the lungs. This mean oscillated volume is an effective method of mucolysis and mucus clearance. HFCC can increase independence. Some studies have...

  9. Computer-aided recognition of emphysema on digital chest radiography.

    OpenAIRE

    Miniati, Massimo; Coppini, Giuseppe; Monti, Simonetta; Bottai, Matteo; Paterni, Marco; Ferdeghini, Ezio Maria

    2011-01-01

    Background Computed tomography (CT) is the benchmark for diagnosis emphysema, but is costly and imparts a substantial radiation burden to the patient. Objective To develop a computer-aided procedure that allows recognition of emphysema on digital chest radiography by using simple descriptors of the lung shape. The procedure was tested against CT. Methods Patients (N=225), who had undergone postero-anterior and lateral digital chest radiographs and CT for diagnostic purposes, were studied and ...

  10. The molecular fingerprint of lung inflammation after blunt chest trauma

    OpenAIRE

    Ehrnthaller, Christian; Flierl, Michael; Perl, Mario; Denk, Stephanie; Unnewehr, Heike; Ward, Peter A.; Radermacher, Peter; Ignatius, Anita; Gebhard, Florian; Chinnaiyan, Arul; Huber-Lang, Markus

    2015-01-01

    Background After severe blunt chest trauma, the development of an acute lung injury (ALI) is often associated with severe or even lethal complications. Especially in multiple injured patients after blunt chest trauma ALI/ARDS [acute respiratory distress syndrome (ARDS)] is frequent. However, in the initial posttraumatic phase, inflammatory clinical signs are often not apparent and underlying changes in gene-expression profile are unknown. Methods Therefore, inflammation in lung tissue followi...

  11. Quick identification of acute chest pain patients study (QICS

    Directory of Open Access Journals (Sweden)

    van der Horst Iwan CC

    2009-06-01

    Full Text Available Abstract Background Patients with acute chest pain are often referred to the emergency ward and extensively investigated. Investigations are costly and could induce unnecessary complications, especially with invasive diagnostics. Nevertheless, chest pain patients have high mortalities. Fast identification of high-risk patients is crucial. Therefore several strategies have been developed including specific symptoms, signs, laboratory measurements, and imaging. Methods/Design The Quick Identification of acute Chest pain Study (QICS will investigate whether a combined use of specific symptoms and signs, electrocardiography, routine and new laboratory measures, adjunctive imaging including electron beam (EBT computed tomography (CT and contrast multislice CT (MSCT will have a high diagnostic yield for patients with acute chest pain. All patients will be investigated according a standardized protocol in the Emergency Department. Serum and plasma will be frozen for future analysis for a wide range of biomarkers at a later time point. The primary endpoint is the safe recognition of low-risk chest pain patients directly at presentation. Secondary endpoint is the identification of a wide range of sensitive predictive clinical markers, chemical biomarkers and radiological markers in acute chest pain patients. Chemical biomarkers will be compared to quantitative CT measurements of coronary atherosclerosis as a surrogate endpoint. Chemical biomarkers will also be compared in head to head comparison and for their additional value. Discussion This will be a very extensive investigation of a wide range of risk predictors in acute chest pain patients. New reliable fast and cheap diagnostic algorithm resulting from the test results might improve chest pain patients' prognosis, and reduce unnecessary costs and diagnostic complications.

  12. Comparison of Fentanyl with Sufentanil for Chest Tube Removal

    Directory of Open Access Journals (Sweden)

    M Golmohammadi

    2008-11-01

    Full Text Available Background: After cardiac surgery, the chest tubes cause pain and their removal is painful and unpleasant forpatients. The aim of this research was to study and compare the analgesic effect of fentanyl and sufentanil on painrelief during chest tube removal in post-cardiac surgical patients.Patients and Methods: A total of 80 patients scheduled for elective cardiac surgery, were recruited in prospective,randomized and double-blind study. Patients received 1.5μg/kg fentanyl or 0.15μg/kg sufentanyl, intravenously10 minutes before removal of chest tube. Pain intensity was assessed by measuring visual analogscale (VAS pain score, 10 minutes before, during, and 5 and10 minutes after removing chest tubes. Level ofsedation, heart rate, arterial blood pressure, and oxygenation saturation were recorded at each stage by a blindedobserver.Results: Mean pain intensity scores 10 minutes before removal of chest tube in fentanyl, and sufentanil groupswere 29.5±12.1 and 31±11.2 respectively. Pain scores during chest tube removal were 38.5±11.6 in fentanylgroup and 44.7±12.8 in sufentanil group (P =0.02. In addition, pain scores during chest tube removal were significantly(P value=0.02 more reduced in fentanyl (17.21±7.5 than in sufentanil group (21.51±11.2. Sedationscores remained low in two groups. None of the patients showed any adverse side effects of opioids. No differenceswere seen in the heart rate or arterial blood pressure, but oxygenation saturation was significantly greaterin sufentanil group than in fentanyl group.Conclusion: Both fentanyl and sufentanil provide adequate analgesia for chest tube removal without increasinguntoward side effects.

  13. Incidentally Detected Enhancing Breast Lesions on Chest Computed Tomography

    OpenAIRE

    Lin, Wen-Chiung; Hsu, Hsian-He; Li, Chao-Shiang; Yu, Jyh-Cherng; Hsu, Giu-Cheng; Yu, Cheng-Ping; Chang, Tsun-Hou; Huang, Guo-Shu

    2011-01-01

    Objective To evaluate the nature and imaging appearance of incidental enhancing breast lesions detected on a routine contrast-enhanced chest CT. Materials and Methods Twenty-three patients with incidental enhancing breast lesions on contrast-enhanced chest CT were retrospectively reviewed. The breast lesions were reviewed by unenhanced and enhanced CT, and evaluated by observing the shapes, margins, enhancement patterns and backgrounds of breast lesions. A histopathologic diagnosis or long-te...

  14. Pleuritic Chest Pain; Where Should We Search for?

    Directory of Open Access Journals (Sweden)

    Mohammad-Hassan Moradinejad

    2011-12-01

    Full Text Available Pleuritic pain is not an unusual problem in children. Other concomitant symptoms should be considered for diagnostic approach in a child with pleuritic chest pain. In this report we discuss chest pain in a 6-year-old child with regard to other signs and symptoms. Finally, we found a rare life-threatening complication of juvenile systemic lupus erythematosus (JSLE in our patient.

  15. Comparison of expectorated sputum after manual chest physical therapy and high-frequency chest compression.

    Science.gov (United States)

    Warwick, Warren J; Wielinski, Catherine L; Hansen, Leland G

    2004-01-01

    This study is a quantitative comparison of the sputum produced by 12 subjects with cystic fibrosis (CF) who received high-frequency chest compression (HFCC) and standard chest physical therapy (CPT) in randomized order. Six subjects routinely used manual CPT and six routinely used the HFCC. None had acute infections or hospitalization in the six weeks before the study. Two certified respiratory therapists alternated subjects and CPT vs HFCC order during the two weeks of the matched study. For all sessions, the expectorated sputum was collected in preweighed cups, which were reweighed immediately after collection and again after evaporation to dryness. The wet and dry weights of the sputum produced as a result of the two techniques were significantly different, with HFCC having greater weight. Regardless of the mode of therapy, the sputum produced by the subjects who regularly received HFCC had greater water content than did the sputum produced by those subjects who regularly received CPT. No significant difference was found between the two therapists regarding sputum expectorated by the subjects during CPT. These results show that sputum production by subjects with CF who receive CPT by certified respiratory therapists can be as great as the sputum produced by the same subjects who receive HFCC. The results also suggest that unknown factors attributed to the therapists may produce different levels of effort from time to time that may decrease the respiratory therapists' effectiveness, whereas the HFCC therapy may be more consistently effective because it is entirely machine based.

  16. Acquisition and analysis strategies in functional MRI at high fields

    International Nuclear Information System (INIS)

    Functional magnetic resonance imaging represents a non-invasive technique to examine neuronal activity in the brain. It applies radio waves to excite nuclear spins, using the emitted signal during relaxation for image generation. Signal modulations from local blood flow and oxygenation level changes caused by neuronal activity are the basis for calculating functional brain maps with high spatial resolution. The present work discusses concepts for improving the spatial and temporal resolution, as well as sophisticated analysis approaches. Besides an exhaustive description of image reconstruction algorithms, computational simulations on echo-shifting in echo-planar imaging are presented and effects on spatial resolution are quantified. The results demonstrate that echo-shifting causes only minimal resolution losses for high signal-to-noise data, but leads to severe resolution degradation (up to 30 %) in images with low signal-to-noise ratios. After an overview of the mechanisms that cause fMRI signal changes subsequent to neuronal activity, explorative analysis algorithms like Fuzzy Cluster Analysis, as well as parametric approaches are described and discussed. In the context of fMRI artifacts, effects of respiratory motion are examined. For the first time, well-defined breathing patterns are used to quantify the influences on fMRI signal intensity. Also, the variability of fMRI activation in a mental rotation paradigm are investigated, using single-trial analysis. Such, intra-subject activation consistency was determined successfully. Finally, in a second study on mental rotation explorative data analysis was applied to retrieve neuro-functional hypotheses. (author)

  17. High-Field MRI and Mercury Release from Dental Amalgam Fillings

    Directory of Open Access Journals (Sweden)

    SMJ Mortazavi

    2014-04-01

    Full Text Available Mercury is among the most toxic nonradioactive elements which may cause toxicity even at low doses. Some studies showed release of mercury from dental amalgam fillings in individuals who used mobile phone. This study was conducted to assess the effect of high-field MRI on mercury release from dental amalgam filling. We studied two groups of students with identical tooth decays requiring a similar pattern of restorative dentistry. They were exposed to a magnetic flux density of 1.5 T produced by a MRI machine. 16 otherwise healthy students with identical dental decay participated in this study. They underwent similar restorative dentistry procedures and randomly divided into two groups of MRI-exposed and control arms. Urinary concentrations of mercury in the control subjects were measured before (hour 0 and 48 and 72 hrs after amalgam restoration, using cold vapor atomic absorption spectrometry. Urinary concentrations of mercury in exposed individuals were determined before (hour 0, and 24, 48, 72 and 96 hrs after amalgam restoration. Unlike control subjects, they underwent conventional brain MRI (15 min, 99 slices, 24 hrs after amalgam restoration. The mean±SD urinary mercury levels in MRI-exposed individuals increased linearly from a baseline value of 20.70±17.96 to 24.83±22.91 μg/L 72 hrs after MRI. In the control group, the concentration decreased linearly from 20.70±19.77 to 16.14±20.05 μg/L. The difference between urinary mercury in the exposed and control group, 72 hrs after MRI (96 h after restoration,was significant (p=0.046. These findings provide further support for the noxious effect of MRI (exposure to strong magnetic fieldand release of mercury from dental amalgam fillings.

  18. High-field MRI and mercury release from dental amalgam fillings.

    Science.gov (United States)

    Mortazavi, S M J; Neghab, M; Anoosheh, S M H; Bahaeddini, N; Mortazavi, G; Neghab, P; Rajaeifard, A

    2014-04-01

    Mercury is among the most toxic nonradioactive elements which may cause toxicity even at low doses. Some studies showed release of mercury from dental amalgam fillings in individuals who used mobile phone. This study was conducted to assess the effect of high-field MRI on mercury release from dental amalgam filling. We studied two groups of students with identical tooth decays requiring a similar pattern of restorative dentistry. They were exposed to a magnetic flux density of 1.5 T produced by a MRI machine. 16 otherwise healthy students with identical dental decay participated in this study. They underwent similar restorative dentistry procedures and randomly divided into two groups of MRI-exposed and control arms. Urinary concentrations of mercury in the control subjects were measured before (hour 0) and 48 and 72 hrs after amalgam restoration, using cold vapor atomic absorption spectrometry. Urinary concentrations of mercury in exposed individuals were determined before (hour 0), and 24, 48, 72 and 96 hrs after amalgam restoration. Unlike control subjects, they underwent conventional brain MRI (15 min, 99 slices), 24 hrs after amalgam restoration. The mean±SD urinary mercury levels in MRI-exposed individuals increased linearly from a baseline value of 20.70±17.96 to 24.83±22.91 μg/L 72 hrs after MRI. In the control group, the concentration decreased linearly from 20.70±19.77 to 16.14±20.05 μg/L. The difference between urinary mercury in the exposed and control group, 72 hrs after MRI (96 h after restoration),was significant (p=0.046). These findings provide further support for the noxious effect of MRI (exposure to strong magnetic field)and release of mercury from dental amalgam fillings.

  19. Chest X ray effective doses estimation in computed radiography

    International Nuclear Information System (INIS)

    Conventional chest radiography is technically difficult because of wide in tissue attenuations in the chest and limitations of screen-film systems. Computed radiography (CR) offers a different approach utilizing a photostimulable phosphor. photostimulable phosphors overcome some image quality limitations of chest imaging. The objective of this study was to estimate the effective dose in computed radiography at three hospitals in Khartoum. This study has been conducted in radiography departments in three centres Advanced Diagnostic Center, Nilain Diagnostic Center, Modern Diagnostic Center. The entrance surface dose (ESD) measurement was conducted for quality control of x-ray machines and survey of operators experimental techniques. The ESDs were measured by UNFORS dosimeter and mathematical equations to estimate patient doses during chest X rays. A total of 120 patients were examined in three centres, among them 62 were males and 58 were females. The overall mean and range of patient dosed was 0.073±0.037 (0.014-0.16) mGy per procedure while the effective dose was 3.4±01.7 (0.6-7.0) mSv per procedure. This study compared radiation doses to patients radiographic examinations of chest using computed radiology. The radiation dose was measured in three centres in Khartoum- Sudan. The results of the measured effective dose showed that the dose in chest radiography was lower in computed radiography compared to previous studies.(Author)

  20. Chest wall segmentation in automated 3D breast ultrasound scans.

    Science.gov (United States)

    Tan, Tao; Platel, Bram; Mann, Ritse M; Huisman, Henkjan; Karssemeijer, Nico

    2013-12-01

    In this paper, we present an automatic method to segment the chest wall in automated 3D breast ultrasound images. Determining the location of the chest wall in automated 3D breast ultrasound images is necessary in computer-aided detection systems to remove automatically detected cancer candidates beyond the chest wall and it can be of great help for inter- and intra-modal image registration. We show that the visible part of the chest wall in an automated 3D breast ultrasound image can be accurately modeled by a cylinder. We fit the surface of our cylinder model to a set of automatically detected rib-surface points. The detection of the rib-surface points is done by a classifier using features representing local image intensity patterns and presence of rib shadows. Due to attenuation of the ultrasound signal, a clear shadow is visible behind the ribs. Evaluation of our segmentation method is done by computing the distance of manually annotated rib points to the surface of the automatically detected chest wall. We examined the performance on images obtained with the two most common 3D breast ultrasound devices in the market. In a dataset of 142 images, the average mean distance of the annotated points to the segmented chest wall was 5.59 ± 3.08 mm. PMID:23273891

  1. A new specifically designed forceps for chest drain insertion.

    LENUS (Irish Health Repository)

    Andrews, Emmet

    2012-02-03

    Insertion of a chest drain can be associated with serious complications. It is recommended that the drain is inserted with blunt dissection through the chest wall but there is no specific instrument to aid this task. We describe a new reusable forceps that has been designed specifically to facilitate the insertion of chest drains.A feasibility study of its use in patients who required a chest drain as part of elective cardiothoracic operations was undertaken. The primary end-point was successful and accurate placement of the drain. The operators also completed a questionnaire rating defined aspects of the procedure. The new instrument was used to insert the chest drain in 30 patients (19 male, 11 female; median age 61.5 years (range 16-81 years)). The drain was inserted successfully without the trocar in all cases and there were no complications. Use of the instrument rated as significantly easier relative to experience of previous techniques in all specified aspects. The new device can be used to insert intercostal chest drains safely and efficiently without using the trocar or any other instrument.

  2. Chest wall segmentation in automated 3D breast ultrasound scans.

    Science.gov (United States)

    Tan, Tao; Platel, Bram; Mann, Ritse M; Huisman, Henkjan; Karssemeijer, Nico

    2013-12-01

    In this paper, we present an automatic method to segment the chest wall in automated 3D breast ultrasound images. Determining the location of the chest wall in automated 3D breast ultrasound images is necessary in computer-aided detection systems to remove automatically detected cancer candidates beyond the chest wall and it can be of great help for inter- and intra-modal image registration. We show that the visible part of the chest wall in an automated 3D breast ultrasound image can be accurately modeled by a cylinder. We fit the surface of our cylinder model to a set of automatically detected rib-surface points. The detection of the rib-surface points is done by a classifier using features representing local image intensity patterns and presence of rib shadows. Due to attenuation of the ultrasound signal, a clear shadow is visible behind the ribs. Evaluation of our segmentation method is done by computing the distance of manually annotated rib points to the surface of the automatically detected chest wall. We examined the performance on images obtained with the two most common 3D breast ultrasound devices in the market. In a dataset of 142 images, the average mean distance of the annotated points to the segmented chest wall was 5.59 ± 3.08 mm.

  3. Intermediate length scale organisation in tin borophosphate glasses: new insights from high field correlation NMR.

    Science.gov (United States)

    Tricot, G; Saitoh, A; Takebe, H

    2015-11-28

    The structure of tin borophosphate glasses, considered for the development of low temperature sealing glasses or anode materials for Li-batteries, has been analysed at the intermediate length scale by a combination of high field standard and advanced 1D/2D nuclear magnetic resonance techniques. The nature and extent of B/P mixing were analysed using the (11)B((31)P) dipolar heteronuclear multiple quantum coherence NMR sequence and the data interpretation allowed (i) detecting the presence and analysing the nature of the B-O-P linkages, (ii) re-interpreting the 1D (31)P spectra and (iii) extracting the proportion of P connected to borate species. Interaction between the different borate species was analysed using the (11)B double quantum-simple quantum experiment to (i) investigate the presence and nature of the B-O-B linkage, (ii) assign the different borate species observed all along the composition line and (iii) monitor the borate network formation. In addition, (119)Sn static NMR was used to investigate the evolution of the chemical environment of the tin polyhedra. Altogether, the set of data allowed determining the structural units constituting the glass network and quantifying the extent of B/P mixing. The structural data were then used to explain the non-linear and unusual evolution of the glass transition temperature.

  4. Spin dynamics of S = 1/2 kagome lattice antiferromagnets observed by high-field ESR

    Energy Technology Data Exchange (ETDEWEB)

    Ohta, Hitoshi [Molecular Photoscience Research Center, Kobe University, Kobe 657-8501 (Japan); Graduate School of Science, Kobe University, Kobe 657-8501 (Japan); Zhang, Wei-min [Graduate School of Science, Kobe University, Kobe 657-8501 (Japan); Okubo, Susumu; Fujisawa, Masashi [Molecular Photoscience Research Center, Kobe University, Kobe 657-8501 (Japan); Sakurai, Takahiro [Center for Supports to Research and Education Activities, Kobe University, Kobe 657-8501 (Japan); Okamoto, Yoshihiko; Yoshida, Hiroyuki; Hiroi, Zenji [Institute for Solid State Physics (ISSP), University of Tokyo, Kashiwa, Chiba 277-8581 (Japan)

    2010-03-15

    Due to the existence of strong spin frustration in a system, the spin dynamics of S = 1/2 kagome lattice antiferromagnet at low temperature has attracted much interest. High-field ESR has been measured on its model substances, Cu{sub 3}V{sub 2}O{sub 7}(OH){sub 2} . 2H{sub 2}O (volborthite) and BaCu{sub 3}V{sub 2}O{sub 3}(OH){sub 2} (vesignieite), down to 1.8 K using pulsed magnetic fields up to 16 T. The measurements are performed for 160 and 315 GHz using polycrys-talline samples. Although both samples showed the g-shift and the change of linewidth at low temperature, volborthite showed a small gap excitation of the order of 40 GHz (1.9 K) while vesignieite showed a paramagnetic behavior down to 1.9 K. Observed difference will be discussed in connection with the crystal structure, and the possible spin liquid state in vesignieite will be discussed. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  5. Methane storage in nanoporous media as observed via high field NMR relaxometry

    CERN Document Server

    Papaioannou, Antonios

    2015-01-01

    The storage properties of methane gas in Vycor porous glass (5.7 nm) are characterized in a wide pressure range from 0.7 MPa-89.7 MPa using Nuclear Magnetic Resonance (NMR). We demonstrate the capability of high field NMR relaxometry for the determination of the methane gas storage capacity and the measurement of the Hydrogen Index, to a high degree of accuracy. This helps determine the excess gas in the pore space which can be identified to exhibit Langmuir properties in the low pressure regime of 0.7 MPa to 39.6 Mpa. The Langmuir model enables us to determine the equilibrium density of the monolayer of adsorbed gas to be 8.5% lower than that of liquid methane. We also identify the signatures of multilayer adsorption at the high pressure regime from 39.6 Mpa to 89.7 Mpa and use the Brunauer-Emmet-Teller (BET) theory to determine the number of adsorbed layers of methane gas. We show how these measurements help us differentiate the gas stored in the Vycor pore space into free and adsorbed fractions for the ent...

  6. Effects of anesthetic agents on brain blood oxygenation level revealed with ultra-high field MRI.

    Directory of Open Access Journals (Sweden)

    Luisa Ciobanu

    Full Text Available During general anesthesia it is crucial to control systemic hemodynamics and oxygenation levels. However, anesthetic agents can affect cerebral hemodynamics and metabolism in a drug-dependent manner, while systemic hemodynamics is stable. Brain-wide monitoring of this effect remains highly challenging. Because T(2*-weighted imaging at ultra-high magnetic field strengths benefits from a dramatic increase in contrast to noise ratio, we hypothesized that it could monitor anesthesia effects on brain blood oxygenation. We scanned rat brains at 7T and 17.2T under general anesthesia using different anesthetics (isoflurane, ketamine-xylazine, medetomidine. We showed that the brain/vessels contrast in T(2*-weighted images at 17.2T varied directly according to the applied pharmacological anesthetic agent, a phenomenon that was visible, but to a much smaller extent at 7T. This variation is in agreement with the mechanism of action of these agents. These data demonstrate that preclinical ultra-high field MRI can monitor the effects of a given drug on brain blood oxygenation level in the absence of systemic blood oxygenation changes and of any neural stimulation.

  7. Posterior diaphragmatic defect detected on chest CT: the incidence according to age and the lateral chest radiographic appearances

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Son Youl; Choi, Yo Won; Jeon, Seok Chol; Heo, Jeong Nam; Park, Choong Ki [College of Medicine, Hanyang University, Seoul (Korea, Republic of)

    2007-03-15

    We wanted to investigate the incidence of posterior diaphragmatic defect on chest CT in various age groups and its lateral chest radiographic appearances. The chest CT scans of 78 patients of various ages with posterior diaphragmatic defect were selected among 1,991 patients, and they were analyzed for the incidence of defect in various age groups, the defect location and the herniated contents. Their lateral chest radiographs were analyzed for the shape of the posterior diaphragm and the posterior costophrenic sulcus. The patients' ages ranged from 34 to 87 with the tendency of a higher incidence in the older patients. The defect most frequently involved the medial two thirds (n = 49, 50.4%) and middle one third (n = 36, 37%) of the posterior diaphragm. The retroperitoneal fat was herniated into the thorax through the defect in all patients, and sometimes with the kidney (n = 8). Lateral chest radiography showed a normal diaphragmatic contour (n = 51, 49.5%), blunting of the posterior costophrenic sulcus (n = 41, 39.8%), focal humping of the posterior diaphragm (n = 7, 6.8%), or upward convexity (n = 4, 3.9%) of the posterior costophrenic sulcus on the affected side. The posterior diaphragmatic defect discovered in asymptomatic patients who are without a history of peridiaphragmatic disease is most likely acquired, and this malady increases in incidence according to age. An abnormal contour of the posterior diaphragm or the costophrenic sulcus on a lateral chest radiograph may be a finding of posterior diaphragmatic defect.

  8. [Chest pain - not always the heart! Clinical impact of gastrointestinal diseases in non-cardiac chest pain].

    Science.gov (United States)

    Frieling, T; Bergdoldt, G; Allescher, H D; Riemann, J F

    2015-02-01

    Non cardiac chest pain (NCCP) are recurrent angina pectoris like pain without evidence of coronary heart disease in conventional diagnostic evaluation. The prevalence of NCCP is up to 70 % and may be detected in this order at all levels of the medical health care system (general practitioner, emergency department, chest pain unit, coronary care). Reduction of quality of life in NCCP is comparable, partially even higher compared to cardiac chest pain. Reasons for psychological strain are symptom recurrence in app. 50 %, nonspecific diagnosis with resulting uncertainty and insufficient integration of other medical disciplines in diagnostic work-up. Managing of patients with NCCP has to be interdisciplinary because non cardiac causes of chest pain may be found frequently. Especially gastroenterological expertise is required because in 50 - 60 % of cases gastroesophageal reflux disease (GERD), in 15 - 18 % hypercontractile esophageal motility disorders with nutcracker, jackhammer esophagus or distal esophageal spasmus or achalasia and in 32 - 35 % other esophageal alterations (e. g. infectious esophageal inflammation, drug-induced ulcer, rings, webs, eosinophilic esophagitis) as cause of chest pain may be detected. This implicates that regular interdisciplinary round wards and management of chest pain units are mandatory.

  9. Chest radiograph usefulness in the diagnosis of acute aortic dissection

    Institute of Scientific and Technical Information of China (English)

    Nancy Welch; Chat Dang; Carlton Allen; Robert Cook

    2005-01-01

    Objective To assess the diagnostic value of chest radiographs in patients presenting to a busy inner-city Emergency Department with subsequently proven acute aortic dissection. Methods A retrospective review of initial chest radiographs and charts of patients with the confirmed diagnosis of acute aortic dissection was done for a period of 5 years from 1998 to 2003. A comparison was made between the initial readings of chest radiographs prior to confirmation of the aortic dissection, and a retrospective review of the same radiographs by two board-certified radiologists with special attention to the classic findings of acute aortic dissection identifiable on plain films. Results The charts of nine patients (four men, five women) with proven acute aortic dissection were reviewed. All nine patients were suspected of having acute aortic dissection based on presenting history and symptoms of chest pain (66% ), migratory pain (89% ), back pain (89% ), and the abruptness of onset of pain (89% ). Initial plain portable chest X-rays were obtained in the Emergency Department in all nine patients. Six of nine (67%) radiographs were read as normal, while three (33%) demonstrated a widened mediastinum (> 8.0cm), two (22%) showed an abnormal aortic contour, with one ( 11% ) displaying an apical cap. Confirmation of the diagnosis was obtained with either a spiral CT angiogram or transesophageal echocardiography (TEE). All nine plain radiographs were retrospectively reviewed by two board-certified radiologists aware of the diagnosis of acute dissection without a change in the readings. Conclusions Plain portable chest radiographs are of limited usefulness for the screening of acute aortic dissection. Further radiologic evaluation should be dictated by the clinical presentation and an awareness of the low sensitivity of portable chest X- rays.

  10. Dose and perceived image quality in chest radiography

    International Nuclear Information System (INIS)

    Chest radiography is the most commonly performed diagnostic X-ray examination. The radiation dose to the patient for this examination is relatively low but because of its frequent use, the contribution to the collective dose is considerable. Consequently, optimization of dose and image quality offers a challenging area of research. In this article studies on dose reduction, different detector technologies, optimization of image acquisition and new technical developments in image acquisition and post processing will be reviewed. Studies indicate that dose reduction in PA chest images to at least 50% of commonly applied dose levels does not affect diagnosis in the lung fields; however, dose reduction in the mediastinum, upper abdomen and retrocardiac areas appears to directly deteriorate diagnosis. In addition to patient dose, also the design of the various digital detectors seems to have an effect on image quality. With respect to image acquisition, studies showed that using a lower tube voltage improves visibility of anatomical structures and lesions in digital chest radiographs but also increases the disturbing appearance of ribs. New techniques that are currently being evaluated are dual energy, tomosynthesis, temporal subtraction and rib suppression. These technologies may improve diagnostic chest X-ray further. They may for example reduce the negative influence of over projection of ribs, referred to as anatomic noise. In chest X-ray this type of noise may be the dominating factor in the detection of nodules. In conclusion, optimization and new developments will enlarge the value of chest X-ray as a mainstay in the diagnosis of chest diseases.

  11. Chest X-ray imaging of patients with SARS

    Institute of Scientific and Technical Information of China (English)

    陆普选; 周伯平; 陈心春; 袁明远; 龚小龙; 杨根东; 刘锦清; 袁本通; 郑广平; 杨桂林; 王火生

    2003-01-01

    Objective To investigate the chest X-ray manifestations of SARS cases.Methods A retrospective study was conducted among 52 clinically confirmed SARS patients from February 9 to May 10, 2003. Chest X-ray scanning was performed at a interval of 1-3 days according to the requirements. The manifestations and special features of SARS in X-ray were analyzed. Results Small or large patchy shadows with intensive density in both lungs were observed in 31 cases, ground-glass like opacification in 16, small patchy shadows in one lung lobe or one lung segment in 18, nodular shadows in one lung segment in 1, and increased lung marking in lung interstitial tissues in 2. Rapidly changing consolidations revealed in chest X-ray images were found to be associated with SARS infections, and they were not affected by treatment with antibiotics.Conclusion Chest X-ray provides a sensitive and specific method for the diagnosis and treatment of SARS, and those present with symptoms and signs should undergo chest X-ray scanning every 1-3 days.

  12. Chest physiotherapy in children with acute bacterial pneumonia

    Directory of Open Access Journals (Sweden)

    Lieselotte Corten

    2015-04-01

    Full Text Available Background: Pneumonia is the single leading cause of death in children younger than 5 years of age. Chest physiotherapy is often prescribed as an additional therapy in children with pneumonia. Different chest physiotherapy techniques are available that aim to improve airway clearance, gas exchange and reduce the work of breathing. However, it is unclear if these techniques are effective in this population.Objective: The present review aimed to determine the efficacy of different chest physiotherapy techniques compared with no physiotherapy or other chest physiotherapy treatments in hospitalised children with bacterial pneumonia.Method: Six electronic databases (PubMed, Medline, Cochrane Library, PEDro, CINAHL and Africa-wide information, clinicaltrials.gov and pactr.org were searched for eligible studies.Results: Two randomised controlled trials and one ongoing study were identified. Neither completed trial reported differences between the control and intervention groups, although one study reported a longer duration of coughing (p = 0.04 and rhonchi (p = 0.03 in the intervention group.Conclusion: Because of the limited number of included articles and different presentations of outcome measures, we could not reject or accept chest physiotherapy as either an effective or harmful treatment option in this population.

  13. Pleural controversy: optimal chest tube size for drainage.

    Science.gov (United States)

    Light, Richard W

    2011-02-01

    In recent years, a higher and higher percentage of patients with pleural effusions or pneumothorax are being treated with small-bore (10-14 F) chest tubes rather than large-bore (>20 F). However, there are very few randomized controlled studies comparing the efficacy and complication rates with the small- and large-bore catheters. Moreover, the randomized trials that are available have flaws in their design. The advantages of the small-bore catheters are that they are easier to insert and there is less pain with their insertion while they are in place. The placement of the small-bore catheters is probably more optimal when placement is done with ultrasound guidance. Small-bore chest tubes are recommended when pleurodesis is performed. The success of the small-bore indwelling tunnelled catheters that are left in place for weeks documents that the small-bore tubes do not commonly become obstructed with fibrin. Patients with complicated parapneumonic effusions are probably best managed with small-bore catheters even when the pleural fluid is purulent. Patients with haemothorax are best managed with large-bore catheters because of blood clots and the high volume of pleural fluid. Most patients with pneumothorax can be managed with aspiration or small-bore chest tubes. If these fail, a large-bore chest tube may be necessary. Patients on mechanical ventilation with barotrauma induced pneumothoraces are best managed with large-bore chest tubes.

  14. CT chest under general anesthesia: pulmonary, anesthetic and radiologic dilemmas

    Energy Technology Data Exchange (ETDEWEB)

    Mahmoud, Mohamed [Cincinnati Children' s Hospital Medical Center, Department of Anesthesiology, Cincinnati, OH (United States); Towe, Christopher [Cincinnati Children' s Hospital Medical Center, Department of Pulmonary Medicine, Cincinnati, OH (United States); Fleck, Robert J. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)

    2015-07-15

    Today's practice of medicine involves ever more complex patients whose care is coordinated with multidisciplinary teams. Caring for these patients can challenge all members of the health care team. Sedation/anesthesia in infants/toddlers as well as uncooperative or intellectually or emotionally impaired children who require imaging studies of the chest are ongoing challenges. High-quality computed tomography (CT) chest imaging studies in children under general anesthesia are extremely important for accurate interpretation and subsequent medical decision-making. Anesthesia-induced atelectasis may obscure or mimic true pathology creating a significant quality issue. Obtaining a high-quality, motion-free chest imaging study in infants and children under general anesthesia remains a difficult task in many institutions. Meticulous attention to anesthesia and imaging techniques and specialized knowledge are required to properly perform and interpret chest imaging studies. In this commentary, we discuss the continuous struggle to obtain high-quality CT chest imaging under general anesthesia. We will also discuss the major concerns of the anesthesiologist, radiologist and pulmonologist and why cooperation and coordination among these providers are critical for an optimal quality study.

  15. Chest x-ray analysis by computer: final technical report

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate and demonstrate the feasibility of the automated analysis of chest x-rays for the classification of pneumoconiosis films according to the U.I.C.C./Cincinnati standard films. Toward this end, computer programs simulating the proposed systems were prepared. Using these programs, the authors then examined three sets of chest radiographs to determine the extent of pneumoconiosis present. The results of the examinations of these x-rays clearly indicated the feasibility of the proposed system. Based on the outcome of these examinations, a complete set of hardware and software specifications were established for a system which can be used for the large scale automatic analysis of chest x-rays

  16. Massive chest wall resection and reconstruction for malignant disease

    Directory of Open Access Journals (Sweden)

    Foroulis CN

    2016-04-01

    Full Text Available Christophoros N Foroulis,1 Athanassios D Kleontas,1 George Tagarakis,1 Chryssoula Nana,1 Ioannis Alexiou,1 Vasilis Grosomanidis,1 Paschalis Tossios,1 Elena Papadaki,2 Ioannis Kioumis,2 Sofia Baka,3 Paul Zarogoulidis,2 Kyriakos Anastasiadis11Department of Cardiothoracic Surgery, Aristotle University School of Medicine, AHEPA University Hospital, 2Pulmonary Department-Oncology Unit, “G. Papanikolaou” General Hospital, Aristotle University of Thessaloniki, 3Oncology Department, European Interbalkan Medical Center, Thessaloniki, GreeceObjective: Malignant chest wall tumors are rare neoplasms. Resection with wide-free margins is an important prognostic factor, and massive chest wall resection and reconstruction are often necessary. A recent case series of 20 consecutive patients is reported in order to find any possible correlation between tumor histology, extent of resection, type of reconstruction, and adjuvant treatment with short- and long-term outcomes.Methods: Twenty patients were submitted to chest wall resection and reconstruction for malignant chest wall neoplasms between 2006 and 2014. The mean age (ten males was 59±4 years. The size and histology of the tumor, the technique of reconstruction, and the short- and long-term follow-up records were noted.Results: The median maximum diameter of tumors was 10 cm (5.4–32 cm. Subtotal sternal resection was performed in nine cases, and the resection of multiple ribs was performed in eleven cases. The median area of chest wall defect was 108 cm2 (60–340 cm2. Histology revealed soft tissue, bone, and cartilage sarcomas in 16 cases (80%, most of them chondrosarcomas. The rest of the tumors was metastatic tumors in two cases and localized malignant pleural mesothelioma and non-Hodgkin lymphoma in one case. The chest wall defect was reconstructed by using the “sandwich technique” (propylene mesh/methyl methacrylate/propylene mesh in nine cases of large anterior defects or by using a 2

  17. Computer-aided diagnosis in chest radiography: Beyond nodules

    Energy Technology Data Exchange (ETDEWEB)

    Ginneken, Bram van [University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands)], E-mail: bram@isi.uu.nl; Hogeweg, Laurens; Prokop, Mathias [University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands)

    2009-11-15

    Chest radiographs are the most common exam in radiology. They are essential for the management of various diseases associated with high mortality and morbidity and display a wide range of findings, many of them subtle. In this survey we identify a number of areas beyond pulmonary nodules that could benefit from computer-aided detection and diagnosis (CAD) in chest radiography. These include interstitial infiltrates, catheter tip detection, size measurements, detection of pneumothorax and detection and quantification of emphysema. Recent work in these areas is surveyed, but we conclude that the amount of research devoted to these topics is modest. Reasons for the slow pace of CAD development in chest radiography beyond nodules are discussed.

  18. Poor interpretation of chest X-rays by junior doctors

    DEFF Research Database (Denmark)

    Christiansen, Janus Mølgaard; Gerke, Oke; Karstoft, Jens;

    2014-01-01

    INTRODUCTION: Studies targeting medical students and junior doctors have shown that their radiological skills are insufficient. Despite the widespread use of chest X-ray; however, a study of Danish junior doctors' skills has not previously been performed. MATERIAL AND METHODS: A total of 22...... participants per-used a standardised series of ten chest X-rays. The test used a multiple-choice form for each image, and the clinical data and the tentative diagnosis of each image were also made available to the participants. For each image, the participant chose a single primary diagnosis; and for each......): 0.41-0.57) and the specificity to 0.55 (95% CI: 0.41-0.68). CONCLUSION: Based on the results from this study, we conclude that BCE doctors do not meet the minimum requirements for radiological diagnostic skills for the use of chest X-ray that were established for this study. FUNDING: not relevant...

  19. RECURRENT SALMONELLA TYPHI CHEST WALL ABSCESSES IN A DIABETIC LADY

    Directory of Open Access Journals (Sweden)

    Jayasri Helen

    2014-09-01

    Full Text Available : Salmonella enterica serovar typhi causing typhoid fever is common in many parts of the world particularly in developing countries. Extra intestinal manifestations are uncommon and occur in immunocompromised individuals such as patients with diabetes, HIV infection, chronic steroid use, chemotherapy and malignancy. We report a case of Salmonella typhi causing recurrent chest wall abscesses in a lady with uncontrolled diabetes. She was admitted with high grade fever, left sided chest wall abscess and a previous history of two similar chest wall abscesses. After hospitalization prompt incision and drainage was done and aerobic culture of pus grew moderate growth of Salmonella typhi resistant to ciprofloxacin and sensitive to cephalosporins. Based on culture report our patient was treated with oral azithromycin for ten days and parenteral ceftriaxone for six weeks. There was rapid and full recovery and six months follow up revealed no recurrence.

  20. Generation and evaluation of an ultra-high-field atlas with applications in DBS planning

    Science.gov (United States)

    Wang, Brian T.; Poirier, Stefan; Guo, Ting; Parrent, Andrew G.; Peters, Terry M.; Khan, Ali R.

    2016-03-01

    Purpose Deep brain stimulation (DBS) is a common treatment for Parkinson's disease (PD) and involves the use of brain atlases or intrinsic landmarks to estimate the location of target deep brain structures, such as the subthalamic nucleus (STN) and the globus pallidus pars interna (GPi). However, these structures can be difficult to localize with conventional clinical magnetic resonance imaging (MRI), and thus targeting can be prone to error. Ultra-high-field imaging at 7T has the ability to clearly resolve these structures and thus atlases built with these data have the potential to improve targeting accuracy. Methods T1 and T2-weighted images of 12 healthy control subjects were acquired using a 7T MR scanner. These images were then used with groupwise registration to generate an unbiased average template with T1w and T2w contrast. Deep brain structures were manually labelled in each subject by two raters and rater reliability was assessed. We compared the use of this unbiased atlas with two other methods of atlas-based segmentation (single-template and multi-template) for subthalamic nucleus (STN) segmentation on 7T MRI data. We also applied this atlas to clinical DBS data acquired at 1.5T to evaluate its efficacy for DBS target localization as compared to using a standard atlas. Results The unbiased templates provide superb detail of subcortical structures. Through one-way ANOVA tests, the unbiased template is significantly (p brain nuclei and an increase in accuracy over single-template and lower field strength atlases.

  1. Integration of ultra-high field MRI and histology for connectome based research of brain disorders

    Directory of Open Access Journals (Sweden)

    Shan eYang

    2013-09-01

    Full Text Available Ultra-high field magnetic resonance imaging (MRI became increasingly relevant for in vivo neuroscientific research because of improved spatial resolutions. However, this is still the unchallenged domain of histological studies, which long played an important role in the investigation of neuropsychiatric disorders. While the field of biological psychiatry strongly advanced on macroscopic levels, current developments are rediscovering the richness of immunohistological information when attempting a multi-level systematic approach to brain function and dysfunction. For most studies, histology sections lost information on three-dimensional reconstructions. Translating histological sections to 3D-volumes would thus not only allow for multi-stain and multi-subject alignment in post mortem data, but also provide a crucial step in big data initiatives involving the network analyses currently performed with in vivo MRI. We therefore investigated potential pitfalls during integration of MR and histological information where no additional blockface information is available. We demonstrated that strengths and requirements from both methods seem to be ideally merged at a spatial resolution of 200 μm. However, the success of this approach is heavily dependent on choices of hardware, sequence and reconstruction. We provide a fully automated pipeline that optimizes histological 3D reconstructions, providing a potentially powerful solution not only for primary human post mortem research institutions in neuropsychiatric research, but also to help alleviate the massive workloads in neuroanatomical atlas initiatives. We further demonstrate (for the first time the feasibility and quality of ultra-high spatial resolution (150 µm isotopic imaging of the entire human brain MRI at 7T, offering new opportunities for analyses on MR-derived information.

  2. High-Field Functional Imaging of Pitch Processing in Auditory Cortex of the Cat.

    Directory of Open Access Journals (Sweden)

    Blake E Butler

    Full Text Available The perception of pitch is a widely studied and hotly debated topic in human hearing. Many of these studies combine functional imaging techniques with stimuli designed to disambiguate the percept of pitch from frequency information present in the stimulus. While useful in identifying potential "pitch centres" in cortex, the existence of truly pitch-responsive neurons requires single neuron-level measures that can only be undertaken in animal models. While a number of animals have been shown to be sensitive to pitch, few studies have addressed the location of cortical generators of pitch percepts in non-human models. The current study uses high-field functional magnetic resonance imaging (fMRI of the feline brain in an attempt to identify regions of cortex that show increased activity in response to pitch-evoking stimuli. Cats were presented with iterated rippled noise (IRN stimuli, narrowband noise stimuli with the same spectral profile but no perceivable pitch, and a processed IRN stimulus in which phase components were randomized to preserve slowly changing modulations in the absence of pitch (IRNo. Pitch-related activity was not observed to occur in either primary auditory cortex (A1 or the anterior auditory field (AAF which comprise the core auditory cortex in cats. Rather, cortical areas surrounding the posterior ectosylvian sulcus responded preferentially to the IRN stimulus when compared to narrowband noise, with group analyses revealing bilateral activity centred in the posterior auditory field (PAF. This study demonstrates that fMRI is useful for identifying pitch-related processing in cat cortex, and identifies cortical areas that warrant further investigation. Moreover, we have taken the first steps in identifying a useful animal model for the study of pitch perception.

  3. Proton density differences in signal characteristics of multiple sclerosis plaques versus white matter lesions of small vessel disease and vasculitis on high-field strength MR images

    International Nuclear Information System (INIS)

    This paper determines if variations in signal intensity characteristics on multi-spin-echo images obtained with a high-field-strength magnet can be useful in differentiating demyelinating plaques of multiple sclerosis from other pathologic white matter processes due to small vessel disease and vasculities. Using the first of two multi-spin-echo images obtained with a General Electric 1.5-T magnet, the investigators compared signal intensity characteristics in 30 patients with a firm clinical diagnosis of multiple sclerosis versus a control group of 30 patients with a known clinical history of small-vessel disease and vasculitis are isodense to gray matter on proton-density images

  4. Role of small calibre chest tube drainage for iatrogenic pneumothorax.

    OpenAIRE

    Laub, M; Milman, N.; Müller, D.; Struve-Christensen, E

    1990-01-01

    A 2 mm Teflon catheter was used as a chest tube in 28 patients with iatrogenic pneumothorax. Frequent aspirations through the catheter were performed in 16 of the patients. In the remaining 12 patients the catheter was connected to a one way flutter valve. The treatment was successful in 27 of the 28 patients--one patient required a large calibre chest tube. The mean drainage time was 48 hours. The small catheter technique is superior to the use of a large intercostal drain as it is much less...

  5. Computer Analysis Of ILO Standard Chest Radiographs Of Pneumoconiosis

    Science.gov (United States)

    Li, C. C.; Shu, David B. C.; Tai, H. T.; Hou, W.; Kunkle, G. A.; Wang, Y.; Hoy, R. J.

    1982-11-01

    This paper presents study of computer analysis of the 1980 ILO standard chest radiographs of pneumoconiosis. Algorithms developed for detection of individual small rounded and irregular opacities have been experimented and evaluated on these standard radiographs. The density, shape, and size distribution of the detected objects in the lung field, in spite of false positives, can be used as indicators for the beginning of pneumoconiosis. This approach is potentially useful in computer-assisted screening and early detection process where the annual chest radiograph of each worker is compared with his (her) own normal radiograph obtained previously.

  6. Melioidosis:a rare cause of anterior chest wall abscess

    Institute of Scientific and Technical Information of China (English)

    Rashidi Ahmad; Azhar Amir Hamzah; Ahmad Kasfi Abdul Rahman; Phee Kheng Cheah

    2010-01-01

    Melioidosis is an unusual tropical infectious disease caused by the gram-negative bacterium Burkholderia pseudomallei, which was formerly known asPseudomonas pseudomallei. Melioidosis is characterized by abscess formation and it may manifest in any part of the human body, however, musculoskeletel melioidosis is uncommon and chest wall melioidosis is very rare. To determine the exact organism based solely on clinical presentation poses a great challenge to the physician. Yet, delay administration of antibiotic may be harmful. We describe a diabetic patient who had anterior chest wall melioidosis that mimicsStaphylococcus aureus infection. A description of his presentation and management, along with a review of literature is presented.

  7. Radiodiagnostic measurements radiation load of children by chest

    International Nuclear Information System (INIS)

    With the aim of optimisation of the radiographic examinations in paediatric radiology the entrance surface doses measured by chest examinations, as the most frequent procedure for children in Slovakia were surveyed. In this paper the results of measurements and calculations of doses obtained by paediatric patients with ages ranging from newborn to 15 years, who undergone chest radiodiagnostic examinations during the year 1996 are presented.. The obtained results are compared with dose assessment procedures based on total absorbed dose calculations using the published conversion factors between energy impaired to the patient and and entrance surface doses integrated over the beam area

  8. HRCT findings of chest complications in patients with leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Nobuyuki; Matsumoto, Tsuneo; Miura, Gouji; Emoto, Takuya; Matsunaga, Naofumi [Department of Radiology, Yamaguchi University School of Medicine (Japan)

    2002-06-01

    High-resolution CT (HRCT) findings of several chest complications occurring in leukemic patients were reviewed. Although most entities show non-specific HRCT findings including ground-glass opacity and air-space consolidation, characteristic findings are observed in several pulmonary complications including Pneumocystis carinii pneumonia, fungal infections, miliary tuberculosis, leukemic infiltration, pulmonary edema, bronchiolitis obliterans, and bronchiolitis obliterans organizing pneumonia. A combination of these characteristic HRCT findings and the information obtained from the clinical setting may help in achieving a correct diagnosis of chest complications occurring in leukemic patients. (orig.)

  9. Evaluation and Management of Chest Pain in the Elderly.

    Science.gov (United States)

    Gupta, Rohit; Munoz, Robert

    2016-08-01

    Geriatric patients are at increased risk for serious morbidity and mortality from life-threatening causes of chest pain. This article covers 5 life-threatening causes of chest pain in the elderly: acute coronary syndrome, aortic dissection, pulmonary embolism, pneumothorax, and esophageal rupture. Atypical presentations, frailty, and significant comorbidities that characterize the elderly make the diagnosis and treatment of these already complicated conditions even more complicated. The emergency provider must be vigilant and maintain a low threshold to test. When a diagnosis is made, treatment must be aggressive. The elderly benefit from optimal care. PMID:27475013

  10. CYSTIC HYGROMA OF CHEST WALL- 2 Reported Cases

    Directory of Open Access Journals (Sweden)

    Tapan Shah

    2012-07-01

    Full Text Available Hygromas arise in the sites of primitive lymphatic lakes, on the floor of the mouth, under the jaw, in the neck and in the axillae, but they can occur virtually anywhere in the body. Their occurrence on the chest wall is very rare and they progressively grow with age infiltrating into the local tissues, insinuating lymphatic pseudopods and form cysts in and around muscle fibers and nerves, making them difficult and hazardous to remove. Here, we have reported 2 cases of cystic hygroma of chest wall in children

  11. CYSTIC HYGROMA OF CHEST WALL- 2 Reported Cases

    OpenAIRE

    Tapan Shah; Dipen Patel; Yash Vaidhya; Jigar Jadeja; Sharad Patel; Asit Patel

    2012-01-01

    Hygromas arise in the sites of primitive lymphatic lakes, on the floor of the mouth, under the jaw, in the neck and in the axillae, but they can occur virtually anywhere in the body. Their occurrence on the chest wall is very rare and they progressively grow with age infiltrating into the local tissues, insinuating lymphatic pseudopods and form cysts in and around muscle fibers and nerves, making them difficult and hazardous to remove. Here, we have reported 2 cases of cystic hygroma of chest...

  12. Chest surgical disorders in ancient Egypt: evidence of advanced knowledge.

    Science.gov (United States)

    Jungraithmayr, Wolfgang; Weder, Walter

    2012-03-01

    The ancient Egyptians laid the foundation for the development of the earliest recorded systems of medical treatment. Many specialties such as gynecology, neurosurgery, ophthalmology, and chest disorders were subject to diagnosis, which were followed by an appropriate treatment. Here, we elucidate the remarkable level of their knowledge and understanding of anatomy and physiology in the field of chest medicine. Furthermore, we look at how ancient Egyptian physicians came to a diagnosis and treatment based on the thoracic cases in the Edwin Smith papyrus. PMID:22330033

  13. Chest X-ray : a cost-diagnostic benefit analysis

    International Nuclear Information System (INIS)

    Although plain chest radiography is one of the most useful diagnostic tools available to the physician, this procedure has not evolved into a consistent method. Two Large Field of View Image Intensifiers (LFOV-II) became available; the large imaging area makes them suitable for chest imaging. Both modalities supply 100 mm images to the radiologist. In this thesis the 'diagnostic benefits and 'costs' of these modalities are evaluated and related to the 'gold' standard (conventional full-size). The emphasis is on diagnostic image quality using phantoms for observer performance qualities. (author). 170 refs.; 21 figs.; 47 tabs

  14. An Unusual Presentation of Adult Tethered Cord Syndrome Associated with Severe Chest and Upper Back Pain

    Directory of Open Access Journals (Sweden)

    Shotaro Kanda

    2015-01-01

    Full Text Available Adult tethered cord syndrome (ATCS is a rare entity that usually presents with multiple neurological symptoms, including lower extremity pain, backache, lower extremity muscle weakness, and bowel/bladder disturbances. Prompt surgical treatment is often necessary to avoid permanent sequelae. We report a 63-year-old man with sudden-onset severe right chest and upper back pain, followed by urinary retention. His initial workup included computed tomography of the abdomen and pelvis, which showed a presacral mass. His symptom-driven neurological workup focused on the cervical and thoracic spine, the results of which were normal. Pelvic radiographs and magnetic resonance imaging of the lumbosacral spine showed spina bifida occulta, meningocele, and presacral masses consistent with a teratomatous tumor. His symptoms, except for urinary retention, improved dramatically with surgical treatment. The excised specimen contained a teratomatous lesion plus an organized hematoma. Hematoma formation was suspected as the trigger of his sudden-onset right chest and upper back pain.

  15. Comparison of high frequency chest compression and conventional chest physiotherapy in hospitalized patients with cystic fibrosis.

    Science.gov (United States)

    Arens, R; Gozal, D; Omlin, K J; Vega, J; Boyd, K P; Keens, T G; Woo, M S

    1994-10-01

    Clearance of bronchial secretions is essential in the management of cystic fibrosis (CF) patients admitted for acute pulmonary exacerbation. Conventional physiotherapy (CPT) is labor-intensive, time-consuming, expensive, and may not be available as frequently as desired during hospitalization. High frequency chest compression (HFCC), which uses an inflatable vest linked to an air-pulse delivery system, may offer an attractive alternative. To study this, we prospectively studied 50 CF patients admitted for acute pulmonary exacerbation who were randomly allocated to receive either HFCC or CPT three times a day. On admission, clinical status and pulmonary function tests (PFT) in the HFCC group were not significantly different from those measured in the CPT group. Significant improvements in clinical status and PFT were observed after 7 and 14 d of treatment, and were similar in the two study groups, leading to patient discharge after similar periods of hospitalization. We conclude that HFCC and CPT are equally safe and effective when used during acute pulmonary exacerbations in CF patients. We speculate that HFCC may provide an adequate alternative in management of CF patients in a hospital setting.

  16. Electron localization effects on the low-temperature high-field magnetoresistivity of three-dimensional amorphous superconductors

    Science.gov (United States)

    Samoilov, A. V.; Yeh, N.-C.; Tsuei, C. C.

    1998-01-01

    The electrical resistivity ρ of three-dimensional amorphous superconducting films a-Mo3Si and a-Nb3Ge is measured in magnetic fields μ0H up to 30 T. At low temperatures and at magnetic fields above the upper critical field Hc2, ρ is temperature independent and decreases as a function of magnetic field. This field dependence is consistent with localization theory in the high-field limit [μ0H>>ħ/(4eL2φ), where Lφ is the phase-coherence length]. Above the superconducting transition temperature Tc, the temperature dependence of the conductivity is consistent with inelastic scattering processes which are destructive to the phase coherence for electron localization, thereby allowing estimates for Lφ(T). The Hall effect data on a-Mo3Si, in conjunction with the resistivity data, allow the determination of the carrier concentration and mean free path. The upper critical field is comparable to (in a-Mo3Si) and significantly larger than (in a-Nb3Ge) the Clogston-Chandrasekhar paramagnetic limit. This phenomenon is discussed in the context of electron localization.

  17. Diagnosis of chest pain with foregut symptoms in Chinese patients

    Institute of Scientific and Technical Information of China (English)

    Bo Deng; Ru-Wen Wang; Yao-Guang Jiang; Qun-You Tan; Xiang-Li Liao; Jing-Hai Zhou; Yun-Ping Zhao; Tai-Qian Gong; Zheng Ma

    2009-01-01

    AIM: To evaluate the diagnosis of chest pain with foregut symptoms in Chinese patients. METHODS: Esophageal manomet r ic studies, 24-h introesophageal pH monitoring and 24-h electrocardiograms (Holter electrocardiography) were performed in 61 patients with chest pain. RESULTS: Thirty-nine patients were diagnosed with non-specific esophageal motility disorders (29 patients with abnormal gastroesophageal reflux and eight patients with myocardial ischemia). Five patients had diffuse spasm of the esophagus plus abnormal gastroesophageal reflux (two patients had concomitant myocardial ischemia), and one patient was diagnosed with nutcracker esophagus. CONCLUSION: The esophageal manometric studies, 24-h intra-esophageal pH monitoring and Holter electrocardiography are significant for the differential diagnosis of chest pain, particularly in patients with foregut symptoms. In cases of esophageal motility disorders, pathological gastroesophageal reflux may be a major cause of chest pain with non-specific esophageal motility disorders. Spasm of the esophageal smooth muscle might affect the heart-coronary smooth muscle, leading to myocardial ischemia.

  18. Picture quiz: a case of sudden severe chest pain.

    Science.gov (United States)

    Rabia, Mustafa Abu; Sullivan, P; Stivaros, Stavros M

    2007-01-01

    An 18-year-old male with no previous medical history presented to hospital with sudden onset of acute epigastric pain radiating to the anterior chest wall and both shoulders. There was no history of recent trauma and he had not been vomiting. PMID:21611610

  19. Chest wall tuberculosis; CT findings in 14 patients

    International Nuclear Information System (INIS)

    To present CT findings of chest wall tuberculosis. CT scans were obtained in 14 patients with proven chest wall tuberculosis. Diagnosis was confirmed by means of right open thoracostomy with abscess evacuation (n=1), excision and curettage (n=11) or excision and curettage along with resection of the involved lung (n=2). The images were assessed with emphasis for the extrapleural, pleural, and pulmonary lesions. All patients showed juxtacostal soft tissue mass with central low attenuation and peripheral rim enhancement. The lesions were located in the left hemithorax in eight patients and in the right in six. Multiple lesions were found in three patients (two in one and three in two). Rib destruction was observed in four patients. Intercostal muscle involvement of thickening and enhancement were shown in all patients. Thirteen patients (93%) had evidence of pulmonary tuberculosis: active pulmonary tuberculosis in nine and stable tuberculosis in four. Pleural lesions, including empyema necessitatis in six, were observed in eleven (79%). On CT scan, chest wall tuberculosis is characterized by juxtacostal soft tissue lesion with central low attenuation and peripheral rim enhancement. Rib destruction may be associated. Additionally, enhancing intercostal muscle suggest direct inflammatory process of tuberculosis and spread channel to the chest wall involvement of pleuropulmonary tuberculosis

  20. Assessment of chest impedance in relation to phonocardiography

    DEFF Research Database (Denmark)

    Zimmermann, Niels Henrik; Møller, Henrik; Hammershøi, Dorte;

    2010-01-01

    ), it is possible to measure the impedance of the surface of the skin and at the same time investigate the influence of different pressures and diameters of a transducer. The impedance tube is made specifically with the purpose of measuring chest impedances in the frequency range from 50 Hz to 5 kHz. An MLS...