WorldWideScience

Sample records for radiation group velocity

  1. Group Velocity for Leaky Waves

    Science.gov (United States)

    Rzeznik, Andrew; Chumakova, Lyubov; Rosales, Rodolfo

    2017-11-01

    In many linear dispersive/conservative wave problems one considers solutions in an infinite medium which is uniform everywhere except for a bounded region. In general, localized inhomogeneities of the medium cause partial internal reflection, and some waves leak out of the domain. Often one only desires the solution in the inhomogeneous region, with the exterior accounted for by radiation boundary conditions. Formulating such conditions requires definition of the direction of energy propagation for leaky waves in multiple dimensions. In uniform media such waves have the form exp (d . x + st) where d and s are complex and related by a dispersion relation. A complex s is required since these waves decay via radiation to infinity, even though the medium is conservative. We present a modified form of Whitham's Averaged Lagrangian Theory along with modulation theory to extend the classical idea of group velocity to leaky waves. This allows for solving on the bounded region by representing the waves as a linear combination of leaky modes, each exponentially decaying in time. This presentation is part of a joint project, and applications of these results to example GFD problems will be presented by L. Chumakova in the talk ``Leaky GFD Problems''. This work is partially supported by NSF Grants DMS-1614043, DMS-1719637, and 1122374, and by the Hertz Foundation.

  2. On whistler-mode group velocity

    International Nuclear Information System (INIS)

    Sazhin, S.S.

    1986-01-01

    An analytical of the group velocity of whistler-mode waves propagating parallel to the magnetic field in a hot anisotropic plasma is presented. Some simple approximate formulae, which can be used for the magnetospheric applications, are derived. These formulae can predict some properties of this group velocity which were not previously recognized or were obtained by numerical methods. In particular, it is pointed out that the anisotropy tends to compensate for the influence of the electron temperature on the value of the group velocity when the wave frequency is well below the electron gyrofrequency. It is predicted, that under conditions at frequencies near the electron gyrofrequency, this velocity tends towards zero

  3. Crack velocity measurement by induced electromagnetic radiation

    International Nuclear Information System (INIS)

    Frid, V.; Rabinovitch, A.; Bahat, D.

    2006-01-01

    Our model of electromagnetic radiation (EMR) emanated from fracture implies that EMR amplitude is proportional to crack velocity. Soda lime glass samples were tested under uniaxial tension. Comparison of crack velocity observed by Wallner line analysis and the peak amplitude of EMR signals registered during the test, showed very good correlation, validating this proportionality

  4. Crack velocity measurement by induced electromagnetic radiation

    Energy Technology Data Exchange (ETDEWEB)

    Frid, V. [Deichmann Rock Mechanics Laboratory of the Negev, Geological and Environmental Sciences Department, Ben Gurion University of the Negev, Beer Sheva (Israel)]. E-mail: vfrid@bgu.ac.il; Rabinovitch, A. [Deichmann Rock Mechanics Laboratory of the Negev, Physics Department, Ben Gurion University of the Negev, Beer Sheva (Israel); Bahat, D. [Deichmann Rock Mechanics Laboratory of the Negev, Geological and Environmental Sciences Department, Ben Gurion University of the Negev, Beer Sheva (Israel)

    2006-07-31

    Our model of electromagnetic radiation (EMR) emanated from fracture implies that EMR amplitude is proportional to crack velocity. Soda lime glass samples were tested under uniaxial tension. Comparison of crack velocity observed by Wallner line analysis and the peak amplitude of EMR signals registered during the test, showed very good correlation, validating this proportionality.

  5. Comparison of high group velocity accelerating structures

    International Nuclear Information System (INIS)

    Farkas, Z.D.; Wilson, P.B.

    1987-02-01

    It is well known that waveguides with no perturbations have phase velocities greater than the velocity of light c. If the waveguide dimensions are chosen so that the phase velocity is only moderately greater than c, only small perturbations are required to reduce the phase velocity to be synchronous with a high energy particle bunch. Such a lightly loaded accelerator structure will have smaller longitudinal and transverse wake potentials and hence will lead to lower emittance growth in an accelerated beam. Since these structures are lightly loaded, their group velocities are only slightly less than c and not in the order of 0.01c, as is the case for the standard disk-loaded structures. To ascertain that the peak and average power requirements for these structures are not prohibitive, we examine the elastance and the Q for several traveling wave structures: phase slip structures, bellows-like structures, and lightly loaded disk-loaded structures

  6. Tailoring group velocity by topology optimization

    DEFF Research Database (Denmark)

    Stainko, Roman; Sigmund, Ole

    2007-01-01

    The paper describes a systematic method for the tailoring of dispersion properties of slab-based photonic crystal waveguides. The method is based on the topology optimization method which consists in repeated finite element frequency domain analyses. The goal of the optimization process is to come...... up with slow light, zero group velocity dispersion photonic waveguides or photonic waveguides with tailored dispersion properties for dispersion compensation purposes. An example concerning the design of a wide bandwidth, constant low group velocity waveguide demonstrate the e±ciency of the method....

  7. Group: radiation dosimetry

    International Nuclear Information System (INIS)

    Caldas, L.V.E.

    1990-01-01

    The main activities of the radiation dosimetry group is described, including the calibration of instruments, sources and radioactive solutions and the determination of neutron flux; development, production and market dosimetric materials; development radiation sensor make the control of radiation dose received by IPEN workers; development new techniques for monitoring, etc. (C.G.C.)

  8. Radiation Protection Group

    CERN Document Server

    2006-01-01

    The Radioactive Waste Section of the Radiation Protection Group wishes to inform you that the Radioactive Waste Treatment Centre will be closed on the afternoon of Tuesday 19 December 2006. Thank-you for your understanding.

  9. Rogue events in the group velocity horizon.

    Science.gov (United States)

    Demircan, Ayhan; Amiranashvili, Shalva; Brée, Carsten; Mahnke, Christoph; Mitschke, Fedor; Steinmeyer, Günter

    2012-01-01

    The concept of rogue waves arises from a mysterious and potentially calamitous phenomenon of oceanic surfaces. There is mounting evidence that they are actually commonplace in a variety of different physical settings. A set of defining criteria has been advanced; this set is of great generality and therefore applicable to a wide class of systems. The question arises naturally whether there are generic mechanisms responsible for extreme events in different systems. Here we argue that under suitable circumstances nonlinear interaction between weak and strong waves results in intermittent giant waves with all the signatures of rogue waves. To obtain these circumstances only a few basic conditions must be met. Then reflection of waves at the so-called group-velocity horizon occurs. The connection between rogue waves and event horizons, seemingly unrelated physical phenomena, is identified as a feature common in many different physical systems.

  10. Distinguishing zero-group-velocity modes in photonic crystals

    International Nuclear Information System (INIS)

    Ghebrebrhan, M.; Ibanescu, M.; Johnson, Steven G.; Soljacic, M.; Joannopoulos, J. D.

    2007-01-01

    We examine differences between various zero-group-velocity modes in photonic crystals, including those that arise from Bragg diffraction, anticrossings, and band repulsion. Zero-group velocity occurs at points where the group velocity changes sign, and therefore is conceptually related to 'left-handed' media, in which the group velocity is opposite to the phase velocity. We consider this relationship more quantitatively in terms of the Fourier decomposition of the modes, by defining a measure of how much the ''average'' phase velocity is parallel to the group velocity--an anomalous region is one in which they are mostly antiparallel. We find that this quantity can be used to qualitatively distinguish different zero-group-velocity points. In one dimension, such anomalous regions are found never to occur. In higher dimensions, they are exhibited around certain zero-group-velocity points, and lead to unusual enhanced confinement behavior in microcavities

  11. Propagation of the Semidiurnal Internal Tide: Phase Velocity Versus Group Velocity

    Science.gov (United States)

    Zhao, Zhongxiang

    2017-12-01

    The superposition of two waves of slightly different wavelengths has long been used to illustrate the distinction between phase velocity and group velocity. The first-mode M2 and S2 internal tides exemplify such a two-wave model in the natural ocean. The M2 and S2 tidal frequencies are 1.932 and 2 cycles per day, respectively, and their superposition forms a spring-neap cycle in the semidiurnal band. The spring-neap cycle acts like a wave, with its frequency, wave number, and phase being the differences of the M2 and S2 internal tides. The spring-neap cycle and energy of the semidiurnal internal tide propagate at the group velocity. Long-range propagation of M2 and S2 internal tides in the North Pacific is observed by satellite altimetry. Along a 3,400 km beam spanning 24°-54°N, the M2 and S2 travel times are 10.9 and 11.2 days, respectively. For comparison, it takes the spring-neap cycle 21.1 days to travel over this distance. Spatial maps of the M2 phase velocity, the S2 phase velocity, and the group velocity are determined from phase gradients of the corresponding satellite observed internal tide fields. The observed phase and group velocities agree with theoretical values estimated using the World Ocean Atlas 2013 annual-mean ocean stratification.

  12. Advisory group on ionising radiation

    International Nuclear Information System (INIS)

    Harrison, J.R.

    1996-01-01

    The Advisory Group on Ionising Radiation has a busy and challenging work programme. Its reports will be published in the Documents of the NRPB series. These may advise further research or could form the basis of formal NRPB advice. Covering the full spectrum of radiation issues at work, in public health and clinical medicine, and the environment, it should enhance the radiation advice available to NRPB. (author)

  13. Control of group velocity by phase-changing collisions

    International Nuclear Information System (INIS)

    Goren, C.; Rosenbluh, M.; Wilson-Gordon, A.D.; Friedmann, H.

    2005-01-01

    We discuss the influence of phase-changing collisions on the group velocities in Doppler-broadened, cycling, degenerate two-level systems where F e =F g +1 and F g >0, interacting with pump and probe lasers, that exhibit electromagnetically induced absorption (EIA). Two model systems are considered: the N system where the pump and probe are polarized perpendicularly, and EIA is due to transfer of coherence (TOC), and the double two-level system (TLS) where both lasers have the same polarization, and EIA is due to transfer of population (TOP). For the case of Doppler-broadened EIA TOC, which occurs at low pump intensity, there is a switch from positive to negative dispersion and group velocity, as the rate of phase-changing collisions is increased. For the case of EIA TOP at low pump intensity, the dispersion and group velocity remain negative even when the collision rate is increased. Pressure-induced narrowing, accompanied by an increase in the magnitude of the negative dispersion and a decrease in the magnitude of the negative group velocity, occurs in both EIA TOC and EIA TOP, at low pump intensity. When the pump intensity is increased, a switch from negative to positive dispersion and group velocity, with increasing collision rate, also occurs in the double TLS system. However, the effect is far smaller than in the case of the N system at low pump intensity

  14. Group-velocity matched nonlinear photonic crystal fibers

    DEFF Research Database (Denmark)

    Bache, Morten; Lægsgaard, Jesper; Bang, Ole

    2006-01-01

    A quadratic nonlinear index-guiding silica PCF is optimized for efficient second-harmonic generation through dispersion calculations. Zero group-velocity mismatch is possible for any pump wavelength above 780 nm. Very high conversion efficiencies and bandwidths are found....

  15. Group velocity tomography and regionalization in Italy and bordering areas

    International Nuclear Information System (INIS)

    Pontevivo, A.; Panza, G.F.

    2001-10-01

    More than one hundred group velocity dispersion curves of the fundamental mode of Rayleigh waves have been processed to obtain tomographic maps, in the period range from 10 s to 35 s, for the Italian peninsula and bordering areas. We compute average dispersion relations over a 1 deg. x 1 deg. grid, and, since the lateral resolving power of our data set is about 200 km, we group the cells of the grid accordingly to their dispersion curves. In this way and without a priori geological constraints, we define seven different regions, each characterised by a distinctive mean group velocity dispersion curve. The resulting regionalization can be easily correlated with the main tectonic features of the study area and mimics a recently proposed structural sketch. Average models of the shear wave velocity in the crust and in the upper mantle for a few selected regions are presented. The very low S-wave velocity values found in the uppermost upper mantle of the Southern Tyrrhenian basin are consistent with a large percentage of partial melting, well in agreement with the presence of the Vavilov-Magnaghi and Marsili huge volcanic bodies. (author)

  16. Slow light with low group-velocity dispersion at the edge of photonic graphene

    Energy Technology Data Exchange (ETDEWEB)

    Ouyang Chunfang; Dong Biqin; Liu Xiaohan; Zi Jian [Department of Physics, Key Laboratory of Micro- and Nanophotonic Structures, Ministry of Education, and Key Laboratory of Surface Physics, Fudan University, Shanghai 200433 (China); Xiong Zhiqiang; Zhao Fangyuan; Hu Xinhua [Department of Material Science and Laboratory of Advanced Materials, Fudan University, Shanghai 200433 (China)

    2011-07-15

    We theoretically study the light propagation at the zigzag edges of a honeycomb photonic crystal (PC), or photonic graphene. It is found that the corresponding edge states have a sinusoidal dispersion similar to those found in PC coupled resonator optical waveguides [CROWs; M. Notomi et al., Nature Photon. 2, 741 (2008)]. The sinusoidal dispersion curve can be made very flat by carefully tuning edge parameters. As a result, low group velocity and small group velocity dispersion can be simultaneously obtained for light propagating at the zigzag edge of photonic graphene. Compared with PC CROWs, our slow-light system exhibits no intrinsic radiation loss and has a larger group velocity bandwidth product. Our results could find applications in on-chip optical buffers and enhanced light-matter interaction.

  17. Real group velocity in a medium with dissipation

    International Nuclear Information System (INIS)

    Muschietti, L.; Dum, C.T.

    1993-01-01

    When a medium is dissipative, the classic expression for the group velocity, dω/dk, is complex with an imaginary part often being far from negligible. To clarify the role of this imaginary term, the motion of a wave packet in a dissipative, homogeneous medium is examined. The integral representation of the packet is analyzed by means of a saddle-point method. It is shown that in a moving frame attached to its maximum the packet looks self-similar. A Gaussian packet keeps its Gaussian identity, as is familiar for the case of a nondissipative medium. However, the central wave number of the packet slowly changes because of a differential damping among the Fourier components: Im(dω/dk)=dγ/dk≠0, where ω≡ω r +iγ. The packet height can be computed self-consistently as integrated damping (or growth). The real group velocity becomes a time-dependent combination of Re(dω/dk) and Im(dω/dk). Only where the medium is both homogeneous and loss free, does the group velocity remain constant. Simple ''ray-tracing equations'' are derived to follow the packet centers in coordinate and Fourier spaces. The analysis is illustrated with a comparison to geometric optics, and by two applications: the case of a medium with some resonant damping (or growth) and the propagation of whistler waves in a collisional plasma

  18. Revisiting the radiative vertical velocity paradigm in the TTL

    Science.gov (United States)

    Bolot, Maximilien; Moyer, Elisabeth

    2015-04-01

    We demonstrate that uplift rates in the TTL (tropical tropopause layer) may be commonly overestimated. The mass balance of any tracer in the TTL depends on the vertical speed of large-scale uplift and the rate of convective detrainment from overshoots. Generally, uplift velocity is retrieved from the conservation of energy, assuming that the only significant factor is radiative heating.1,2 The detrainment rate is then computed from the convergence of the uplift flux, with the assumption that detrainment dominates over entrainment in the TTL. We show that this commonly calculated 'radiative vertical velocity' and the associated rate of detrainment are necessarily flawed for either of two mutually exclusive reasons. If radiative heating is the sole diabatic term in the energy budget, then significant convective entrainment must occur at TTL levels. If detrainment dominates over entrainment, then the heat budget must include the cooling rate from the export of sensible heat deficit in overshooting convection. We illustrate the calculations using tropical values of radiative heating rates and large-scale divergence fluxes from ERA-Interim reanalysis. For undilute convection, the export of heat deficit in detrained overshoots would substantially offset radiative heating, lowering the resulting assumed vertical velocity at 16 km by a factor of three. The computed detrainment rate at this altitude also increases significantly, by a factor of five. Because these changes would alter interpretation of tracer profiles, it is important to include all terms in the heat budget in tracer studies. Conversely, tracer transport properties can be used to help constrain the impact of convection on the TTL heat budget.3 [1] Folkins, I. et al., J. Geophys. Res., 111, D23304, (2006). [2] Read, W. G. et al., Atmos. Chem. Phys., 8, 6051-6067, (2008). [3] Kuang, Z. and Bretherton, C. S., J. Atmos. Sci., 61, 2919-2927, (2004)

  19. Renal shear wave velocity by acoustic radiation force impulse did not reflect advanced renal impairment.

    Science.gov (United States)

    Takata, Tomoaki; Koda, Masahiko; Sugihara, Takaaki; Sugihara, Shinobu; Okamoto, Toshiaki; Miyoshi, Kenichi; Matono, Tomomitsu; Hosho, Keiko; Mae, Yukari; Iyama, Takuji; Fukui, Takeaki; Fukuda, Satoko; Munemura, Chishio; Isomoto, Hajime

    2016-12-01

    Acoustic radiation force impulse is a noninvasive method for evaluating tissue elasticity on ultrasound. Renal shear wave velocity measured by this technique has not been fully investigated in patients with renal disease. The aim of the present study was to compare renal shear wave velocity in end-stage renal disease patients and that in patients without chronic kidney disease and to investigate influencing factors. Renal shear wave velocities were measured in 59 healthy young subjects (control group), 31 subjects without chronic kidney disease (non-CKD group), and 39 end-stage renal disease patients (ESRD group). Each measurement was performed 10 times at both kidneys, and the mean value of eight of 10 measurements, excluding the maximum and minimum values, was compared. Renal shear wave velocity could be measured in all subjects. Renal shear wave velocity in the control group was higher than in the non-CKD group and in the ESRD group, and no difference was found between the non-CKD group and the ESRD group. Age and depth were negatively correlated to the renal shear wave velocity. In multiple regression analysis, age and depth were independent factors for renal shear wave velocity, while renal impairment was not. There was no difference between the non-CKD group and the ESRD group, even when ages were matched and depth was adjusted. Renal shear wave velocity was not associated with advanced renal impairment. However, it reflected alteration of renal aging, and this technique may be useful to detect renal impairment in the earlier stages. © 2015 Asian Pacific Society of Nephrology.

  20. Radiation sources working group summary

    International Nuclear Information System (INIS)

    Fazio, M.V.

    1998-01-01

    The Radiation Sources Working Group addressed advanced concepts for the generation of RF energy to power advanced accelerators. The focus of the working group included advanced sources and technologies above 17 GHz. The topics discussed included RF sources above 17 GHz, pulse compression techniques to achieve extreme peak power levels, components technology, technology limitations and physical limits, and other advanced concepts. RF sources included gyroklystrons, magnicons, free-electron masers, two beam accelerators, and gyroharmonic and traveling wave devices. Technology components discussed included advanced cathodes and electron guns, high temperature superconductors for producing magnetic fields, RF breakdown physics and mitigation, and phenomena that impact source design such as fatigue in resonant structures due to RF heating. New approaches for RF source diagnostics located internal to the source were discussed for detecting plasma and beam phenomena existing in high energy density electrodynamic systems in order to help elucidate the reasons for performance limitations

  1. Waves in microstructured solids and negative group velocity

    Science.gov (United States)

    Peets, T.; Kartofelev, D.; Tamm, K.; Engelbrecht, J.

    2013-07-01

    Waves with negative group velocity (NGV) were discovered in optics by Sommerfeld and Brillouin, and experimentally verified in many cases, for example in left-handed media. For waves in solids, such an effect is described mostly in layered media. In this paper, it is demonstrated that in microstructured solids, waves with NGV may also exist leading to backwards pulse propagation. Two physical cases are analysed: a Mindlin-type hierarchical (a scale within a scale) material and a felt-type (made of fibres) material. For both cases, the dispersion analysis of one-dimensional waves shows that there exists certain ranges of physical parameters which lead to NGV. The results can be used in dispersion engineering for designing materials with certain properties.

  2. Rayleigh wave group velocity and shear wave velocity structure in the San Francisco Bay region from ambient noise tomography

    Science.gov (United States)

    Li, Peng; Thurber, Clifford

    2018-06-01

    We derive new Rayleigh wave group velocity models and a 3-D shear wave velocity model of the upper crust in the San Francisco Bay region using an adaptive grid ambient noise tomography algorithm and 6 months of continuous seismic data from 174 seismic stations from multiple networks. The resolution of the group velocity models is 0.1°-0.2° for short periods (˜3 s) and 0.3°-0.4° for long periods (˜10 s). The new shear wave velocity model of the upper crust reveals a number of important structures. We find distinct velocity contrasts at the Golden Gate segment of the San Andreas Fault, the West Napa Fault, central part of the Hayward Fault and southern part of the Calaveras Fault. Low shear wave velocities are mainly located in Tertiary and Quaternary basins, for instance, La Honda Basin, Livermore Valley and the western and eastern edges of Santa Clara Valley. Low shear wave velocities are also observed at the Sonoma volcanic field. Areas of high shear wave velocity include the Santa Lucia Range, the Gabilan Range and Ben Lomond Plutons, and the Diablo Range, where Franciscan Complex or Silinian rocks are exposed.

  3. Radiation Protection Group annual report (1997)

    International Nuclear Information System (INIS)

    Hoefert, M.

    1998-01-01

    The Annual Report of the Radiation Protection Group is intended to inform the Host State Authorities, as well as the CERN Management and staff, about the radiological situation at CERN during the year 1997. The structure of the present report follows that of previous years and has five sections. It presents the results of environmental radiation monitoring, gives information about the radiation control on the sites of the Organization, describes the radiation protection activities around the CERN accelerators, reports on personnel dosimetry, calibration and instrumentation, and briefly comments on the non-routine activities of the Radiation Protection Group

  4. Radiation Protection Group annual report (1996)

    International Nuclear Information System (INIS)

    Hoefert, M.

    1997-01-01

    The Annual Report of the Radiation Protection Group is intended to inform the Host State Authorities, as well as the CERN Management and staff, about the radiological situation at CERN during the year 1996. The structure of the present report follows that of previous years and has five sections. It presents the results of environmental radiation monitoring, gives information about the radiation control on the sites of the Organization, describes the radiation protection activities around the CERN accelerators, reports on personnel dosimetry, calibration and instrumentation, and briefly comments on the non-routine activities of the Radiation Protection Group

  5. Radiation Protection Group annual report (1998)

    International Nuclear Information System (INIS)

    Hoefert, M.

    1999-01-01

    The Annual Report of the Radiation Protection Group is intended to inform the Host State Authorities, as well as the CERN Management and staff, about the radiological situation at CERN during the year 1998. The structure of the present report follows that of previous years and has five sections. It presents the results of environmental radiation monitoring, gives information about the radiation control on the sites of the Organization, describes the radiation protection activities around the CERN accelerators, reports on personnel dosimetry, calibration and instrumentation, and briefly comments on the non-routine activities of the Radiation Protection Group

  6. Radiation Protection Group annual report (1996)

    Energy Technology Data Exchange (ETDEWEB)

    Hoefert, M [ed.

    1997-03-25

    The Annual Report of the Radiation Protection Group is intended to inform the Host State Authorities, as well as the CERN Management and staff, about the radiological situation at CERN during the year 1996. The structure of the present report follows that of previous years and has five sections. It presents the results of environmental radiation monitoring, gives information about the radiation control on the sites of the Organization, describes the radiation protection activities around the CERN accelerators, reports on personnel dosimetry, calibration and instrumentation, and briefly comments on the non-routine activities of the Radiation Protection Group.

  7. Radiation Protection Group annual report (1998)

    Energy Technology Data Exchange (ETDEWEB)

    Hoefert, M [ed.

    1999-04-15

    The Annual Report of the Radiation Protection Group is intended to inform the Host State Authorities, as well as the CERN Management and staff, about the radiological situation at CERN during the year 1998. The structure of the present report follows that of previous years and has five sections. It presents the results of environmental radiation monitoring, gives information about the radiation control on the sites of the Organization, describes the radiation protection activities around the CERN accelerators, reports on personnel dosimetry, calibration and instrumentation, and briefly comments on the non-routine activities of the Radiation Protection Group.

  8. Radiation Protection Group annual report (1997)

    Energy Technology Data Exchange (ETDEWEB)

    Hoefert, M [ed.

    1998-04-10

    The Annual Report of the Radiation Protection Group is intended to inform the Host State Authorities, as well as the CERN Management and staff, about the radiological situation at CERN during the year 1997. The structure of the present report follows that of previous years and has five sections. It presents the results of environmental radiation monitoring, gives information about the radiation control on the sites of the Organization, describes the radiation protection activities around the CERN accelerators, reports on personnel dosimetry, calibration and instrumentation, and briefly comments on the non-routine activities of the Radiation Protection Group.

  9. Radiation Protection Group annual report (1995)

    International Nuclear Information System (INIS)

    Hoefert, M.

    1996-01-01

    The Annual Report of the Radiation Protection Group is intended to inform the Host State Authorities, as well as the CERN Management and staff, about the radiological situation at CERN during the year 1995. The structure of the present report follows that of previous years and has five sections. It presents the results of environmental radiation monitoring, gives information about the radiation control on the sites of the Organization, describes the radiation protection activities around the CERN accelerators, reports on personnel dosimetry, calibration and instrumentation, and briefly comments on the non-routine activities of the Radiation Protection Group

  10. The peculiar velocity of the Local Group: Pt. 3

    International Nuclear Information System (INIS)

    Staveley-Smith, L.; Davies, R.D.

    1989-01-01

    Utilizing our all-sky survey of spiral galaxies, we have derived a basic description of the extragalactic peculiar velocity field. In agreement with the results of previous authors, highly significant dipole and quadrupole terms are found. These are interpreted using a number of physically simple, but plausible models. No single attractor is able to explain all of the motions observed in nearby galaxies, but the region surrounding the Centaurus cluster appears to have the dominant effect. (author)

  11. THE VELOCITY DISTRIBUTION OF NEARBY STARS FROM HIPPARCOS DATA. II. THE NATURE OF THE LOW-VELOCITY MOVING GROUPS

    International Nuclear Information System (INIS)

    Bovy, Jo; Hogg, David W.

    2010-01-01

    The velocity distribution of nearby stars (∼<100 pc) contains many overdensities or 'moving groups', clumps of comoving stars, that are inconsistent with the standard assumption of an axisymmetric, time-independent, and steady-state Galaxy. We study the age and metallicity properties of the low-velocity moving groups based on the reconstruction of the local velocity distribution in Paper I of this series. We perform stringent, conservative hypothesis testing to establish for each of these moving groups whether it could conceivably consist of a coeval population of stars. We conclude that they do not: the moving groups are neither trivially associated with their eponymous open clusters nor with any other inhomogeneous star formation event. Concerning a possible dynamical origin of the moving groups, we test whether any of the moving groups has a higher or lower metallicity than the background population of thin disk stars, as would generically be the case if the moving groups are associated with resonances of the bar or spiral structure. We find clear evidence that the Hyades moving group has higher than average metallicity and weak evidence that the Sirius moving group has lower than average metallicity, which could indicate that these two groups are related to the inner Lindblad resonance of the spiral structure. Further, we find weak evidence that the Hercules moving group has higher than average metallicity, as would be the case if it is associated with the bar's outer Lindblad resonance. The Pleiades moving group shows no clear metallicity anomaly, arguing against a common dynamical origin for the Hyades and Pleiades groups. Overall, however, the moving groups are barely distinguishable from the background population of stars, raising the likelihood that the moving groups are associated with transient perturbations.

  12. Group velocity measurement using spectral interference in near-field scanning optical microscopy

    International Nuclear Information System (INIS)

    Mills, John D.; Chaipiboonwong, Tipsuda; Brocklesby, William S.; Charlton, Martin D. B.; Netti, Caterina; Zoorob, Majd E.; Baumberg, Jeremy J.

    2006-01-01

    Near-field scanning optical microscopy provides a tool for studying the behavior of optical fields inside waveguides. In this experiment the authors measure directly the variation of group velocity between different modes of a planar slab waveguide as the modes propagate along the guide. The measurement is made using the spectral interference between pulses propagating inside the waveguide with different group velocities, collected using a near-field scanning optical microscope at different points down the guide and spectrally resolved. The results are compared to models of group velocities in simple guides

  13. Transverse velocity modulator and generator schemes based on non-collinear radiation and electron beams

    CERN Document Server

    Varfolomeev, A A

    2000-01-01

    New non-collinear schemes are suggested for transverse velocity modulation of electron beams and for the generation of coherent spontaneous radiation by these transversely modulated beams. It is shown that due to the non-collinearity some orders of magnitude enhancement can be achieved for the coherent spontaneous radiation (CSR) power at both the fundamental and harmonic frequencies.

  14. High resolution Rayleigh wave group velocity tomography in North-China from ambient seismic noise

    International Nuclear Information System (INIS)

    Fang Lihua; Wu Jianping; Ding Zhifeng; Panza, G.F.

    2009-03-01

    This study presents the results of the Rayleigh wave group velocity tomography in North-China performed using ambient seismic noise observed at 190 broadband and 10 very broadband stations of the North-China Seismic Array. All available vertical component time-series for the 14 months span between January, 2007 and February, 2008 are cross-correlated to obtain empirical Rayleigh wave Green functions that are subsequently processed, with the multiple filter method, to isolate the group velocity dispersion curves of the fundamental mode of Rayleigh wave. Tomographic maps, with a grid spacing of 0.25 deg. x 0.25 deg., are computed at the periods of 4.5s, 12s, 20s, 28s. The maps at short periods reveal an evident lateral heterogeneity in the crust of North-China, quite well in agreement with known geological and tectonic features. The North China Basin is imaged as a broad low velocity area, while the Taihangshan and Yanshan uplifts and Ordos block are imaged as high velocity zones, and the Quaternary intermountain basins show up as small low-velocity anomalies. The group velocity contours at 4.5s, 12s and 20s are consistent with the Bouguer gravity anomalies measured in the area of the Taihangshan fault, that cuts through the lower crust at least. Most of the historical strong earthquakes (M≥6.0) are located where the tomographic maps show zones with moderate velocity gradient. (author)

  15. Phase and group velocities for Lamb waves in DOP-26 iridium alloy sheet

    International Nuclear Information System (INIS)

    Simpson, W.A.; McGuire, D.J.

    1994-07-01

    The relatively coarse grain structure of iridium weldments limits the ultrasonic inspection of these structures to frequencies in the low megahertz range. As the material thickness is nominally 0.635 mm for clad vent set capsules, the low frequencies involved necessarily entail the generation of Lamb waves m the specimen. These waves are, of course, dispersive and detailed knowledge of both the phase and group velocities is required in order to determine accurately the location of flaws detected using Lamb waves. Purpose of this study is to elucidate the behavior of Lamb waves propagating in the capsule alloy and to quantify the velocities so that accurate flaw location is ensured. We describe a numerical technique for computing the phase velocities of Lamb waves (or of any other type of guided wave) and derive the group velocities from this information. A frequency-domain method is described for measuring group velocity when multiple Lamb modes are present and mutually interfering in the time domain, and experimental confirmation of the group velocity is presented for the capsule material

  16. Radiation Protection Group Annual Report 2003

    CERN Document Server

    Silari, M

    2004-01-01

    The RP Annual Report summarises the activities carried out by CERN’s Radiation Protection Group in the year 2003. It includes contribution from the EN section of the TIS/IE Group on environmental monitoring. Chapter 1 reports on the measurements and estimations of the impact on the environment and public exposure due to the Organisation’s activities. Chapter 2 provides the results of the monitoring of CERN’s staff, users and contractors to occupational exposure. Chapter 3 deals with operational radiation protection around the accelerators and in the experimental areas. Chapter 4 reports on RP design studies for the LHC and CNGS projects. Chapter 5 addresses the various services provided by the RP Group to other Groups and Divisions at CERN, which include managing radioactive waste, high-level dosimetry, lending radioactive test sources and shipping radioactive materials. Chapter 6 describes activities other than the routine and service tasks, i.e. development work in the field of instrumentation and res...

  17. Helioseismic measurements in the solar envelope using group velocities of surface waves

    Science.gov (United States)

    Vorontsov, S. V.; Baturin, V. A.; Ayukov, S. V.; Gryaznov, V. K.

    2014-07-01

    At intermediate- and high-degree l, solar p and f modes can be considered as surface waves. Using variational principle, we derive an integral expression for the group velocities of the surface waves in terms of adiabatic eigenfunctions of normal modes, and address the benefits of using group-velocity measurements as a supplementary diagnostic tool in solar seismology. The principal advantage of using group velocities, when compared with direct analysis of the oscillation frequencies, comes from their smaller sensitivity to the uncertainties in the near-photospheric layers. We address some numerical examples where group velocities are used to reveal inconsistencies between the solar models and the seismic data. Further, we implement the group-velocity measurements to the calibration of the specific entropy, helium abundance Y, and heavy-element abundance Z in the adiabatically stratified part of the solar convective envelope, using different recent versions of the equation of state. The results are in close agreement with our earlier measurements based on more sophisticated analysis of the solar oscillation frequencies. These results bring further support to the downward revision of the solar heavy-element abundances in recent spectroscopic measurements.

  18. Offshore Rayleigh Group Velocity Observations of the South Island, New Zealand, from Ambient Noise Data

    KAUST Repository

    Yeck, William L.; Sheehan, Anne F.; Stachnik, Joshua C.; Lin, Fan-Chi

    2017-01-01

    We present azimuthally anisotropic Rayleigh group velocity models from 8 - 35 s both offshore and onshore of the South Island of New Zealand. We use MOANA (Marine Observations of Anisotropy Near Aotearoa) broadband ocean seismic data in combination with on land data from the New Zealand National Seismography Network (NZNSN) to investigate the seismic structure of the flanks of the Australian-Pacific plate boundary. At 8 s, we observe low offshore group velocities best explained by the influence of the water layer and thick water-laden sediments. At long periods (20-30 s), group velocities are lower on the South Island relative to its offshore flanks, due to thickened crust beneath the island, with the lowest velocities primarily beneath the Southern Alps. Group velocity azimuthal anisotropy fast directions near the Alpine Fault align with the direction of relative plate motion between the Australian and Pacific plates. In the southern portion of the island, fast directions rotate anticlockwise, likely in response to a decrease in dextral shearing away from the plate boundary. Azimuthal anisotropy fast directions align with absolute plate motion offshore on the Pacific plate. Based on the depth sensitivity of our observations, we suggest diffuse deformation occurs throughout the crust. Our observations match trends in previous Pn anisotropy and SKS shear wave splitting observations, and therefore suggest a consistent pattern of distributed deformation throughout the lithosphere.

  19. Offshore Rayleigh Group Velocity Observations of the South Island, New Zealand, from Ambient Noise Data

    KAUST Repository

    Yeck, William L.

    2017-02-15

    We present azimuthally anisotropic Rayleigh group velocity models from 8 - 35 s both offshore and onshore of the South Island of New Zealand. We use MOANA (Marine Observations of Anisotropy Near Aotearoa) broadband ocean seismic data in combination with on land data from the New Zealand National Seismography Network (NZNSN) to investigate the seismic structure of the flanks of the Australian-Pacific plate boundary. At 8 s, we observe low offshore group velocities best explained by the influence of the water layer and thick water-laden sediments. At long periods (20-30 s), group velocities are lower on the South Island relative to its offshore flanks, due to thickened crust beneath the island, with the lowest velocities primarily beneath the Southern Alps. Group velocity azimuthal anisotropy fast directions near the Alpine Fault align with the direction of relative plate motion between the Australian and Pacific plates. In the southern portion of the island, fast directions rotate anticlockwise, likely in response to a decrease in dextral shearing away from the plate boundary. Azimuthal anisotropy fast directions align with absolute plate motion offshore on the Pacific plate. Based on the depth sensitivity of our observations, we suggest diffuse deformation occurs throughout the crust. Our observations match trends in previous Pn anisotropy and SKS shear wave splitting observations, and therefore suggest a consistent pattern of distributed deformation throughout the lithosphere.

  20. Radiation Sources Working Group Summary Report

    International Nuclear Information System (INIS)

    Fazio, Michael V.

    1999-01-01

    The Radiation Sources Working Group addressed advanced concepts for the generation of RF energy to power advanced accelerators. The focus of the working group included advanced sources and technologies above 17 GHz. The topics discussed included RF sources above 17 GHz, pulse compression techniques to achieve extreme peak power levels, component technology, technology limitations and physical limits, and other advanced concepts. RF sources included gyroklystrons, magnicons, free-electron masers, two beam accelerators, and gyroharmonic and traveling wave devices. Technology components discussed included advanced cathodes and electron guns, high temperature superconductors for producing magnetic fields, RF breakdown physics and mitigarion, and phenomena that impact source design such as fatigue in resonant structures due to pulsed RF heating. New approaches for RF source diagnostics located internal to the source were discussed for detecting plasma and beam phenomena existing in high energy density electrodynamic systems in order to help elucidate the reasons for performance limitations

  1. Radiation Sources Working Group Summary Report

    International Nuclear Information System (INIS)

    Fazio, M.V.

    1999-01-01

    The Radiation Sources Working Group addressed advanced concepts for the generation of RF energy to power advanced accelerators. The focus of the working group included advanced sources and technologies above 17 GHz. The topics discussed included RF sources above 17 GHz, pulse compression techniques to achieve extreme peak power levels, component technology, technology limitations and physical limits, and other advanced concepts. RF sources included gyroklystrons, magnicons, free-electron masers, two beam accelerators, and gyroharmonic and traveling wave devices. Technology components discussed included advanced cathodes and electron guns, high temperature superconductors for producing magnetic fields, RF breakdown physics and mitigarion, and phenomena that impact source design such as fatigue in resonant structures due to pulsed RF heating. New approaches for RF source diagnostics located internal to the source were discussed for detecting plasma and beam phenomena existing in high energy density electrodynamic systems in order to help elucidate the reasons for performance limitations. copyright 1999 American Institute of Physics

  2. An experiment to measure the one-way velocity of propagation of electromagnetic radiation

    Science.gov (United States)

    Kolen, P.; Torr, D. G.

    1982-01-01

    An experiment involving commercially available instrumentation to measure the velocity of the earth with respect to absolute space is described. The experiment involves the measurement of the one-way propagation velocity of electromagnetic radiation down a high-quality coaxial cable. It is demonstrated that the experiment is both physically meaningful and exceedingly simple in concept and in implementation. It is shown that with currently available commercial equipment one might expect to detect a threshold value for the component of velocity of the earth's motion with respect to absolute space in the equatorial plane of approximately 10 km/s, which greatly exceeds the velocity resolution required to detect the motion of the solar system with respect to the center of the galaxy.

  3. Determination of group velocity of propagation of Lamb waves in aluminium plate using piezoelectric transducers

    Directory of Open Access Journals (Sweden)

    Lašová Z.

    2017-06-01

    Full Text Available A prior knowledge of group velocities of Lamb wave modes is a key for analysis of time signals in guidedwave based structural health monitoring. The identification of multiple wave modes may be complicated due to dependency of group velocity on frequency (dispersion. These dependencies for infinite plate of constant thickness can be calculated by a numerical solution of analytic equation. Two alternative approaches to determine group velocities of zero-order Lamb wave modes in aluminum plate were used in this work: Two-dimensional Fast Fourier Transform (2D-FFT and methods of time-frequency processing. 2D-FFT requires a high number of time signals in equidistant points, therefore it was applied on data from finite element analysis of wave propagation in the plate. Group velocities for chosen frequencies were also determined using wavelet transform (WT of signals as differencies of times of arrival measured by a pair of piezoelectric transducers. The results from 2D-FFT and wavelet transform were compared to the analytic solution.

  4. Effect of group velocity mismatch on acousto-optic interaction of ultrashort laser pulses

    International Nuclear Information System (INIS)

    Yushkov, K B; Molchanov, V Ya

    2011-01-01

    Equations describing acousto-optic diffraction of ultrashort laser pulses in an anisotropic medium are derived, taking into account the group velocity mismatch of optical eigenmodes. It is shown that the solution of the modified coupled-mode equations taking into account the group delay is characterised by an increase in the pulse duration, a decrease in diffraction efficiency, a change in the shape of the wave packet envelope, as well as by an increase in the width of the transmission function.

  5. Motor conduction velocity in the human spinal cord: slowed conduction in multiple sclerosis and radiation myelopathy

    International Nuclear Information System (INIS)

    Snooks, S.J.; Swash, M.

    1985-01-01

    Transcutaneous electrical stimulation of the central nervous system was used to measure motor conduction velocity in the human spinal cord in 21 subjects aged 22 to 75 years (mean 55 years), none of whom had neurological disease. The motor conduction velocity between the sixth cervical (C6) and first lumbar (L1) vertebral levels was 67.4+-9.1 m/s. This probably represents conduction velocity in the corticospinal tracts. In these subjects the motor conduction velocity in the cauda equina, between the first lumbar (L1) and fourth lumbar (L4) vertebral levels, was 57.9+-10.3 m/s. In four of five patients with multiple sclerosis, all with corticospinal signs in the legs, motor conduction velocity between C6 and L1 was slowed (41.8+-16.8 m/s), but cauda equina conduction was normal (55.8+-7.8 m/s). Similar slowing of spinal cord motor conduction was found in a patient with radiation myelopathy. This method should provide a relevant, simple clinical test in patients with spinal cord disease. (author)

  6. Group velocity measurement from the propagation of the ionization front in a surface-wave-produced plasma

    International Nuclear Information System (INIS)

    Cotrino, J.; Gamero, A.; Sola, A.; Lao, C.

    1989-01-01

    During the first instant, previous to steady-state in a surface-wave-produced plasma, an ionization front advance front the launcher to the plasma column end. The velocity of the ionization front is much slower than the group velocity of the surface wave, this give a reflection of the incident signal on the moving ionization front. In this paper, the authors use this effect to calculate the surface wave group velocity

  7. Rayleigh wave group-velocity across the Dominican Republic and Puerto Rico from ambient noise tomography

    Science.gov (United States)

    Quiros, D.; Pulliam, J.; Polanco Rivera, E.; Huerfano Moreno, V. A.

    2017-12-01

    The eastern North America-Caribbean (NA-CAR) plate boundary near the islands of Hispaniola (which is comprised of the Dominican Republic and Haiti) and Puerto Rico is a complex transition zone in which strain is accommodated by two transform fault systems and oblique subduction. In 2013, scientists from Baylor University, the Autonomous University of Santo Domingo, and the Puerto Rico Seismic Network deployed 16 broadband stations on the Dominican Republic to expand the local permanent network. The goal of the Greater Antilles Seismic Program (GrASP) is to combine its data with that from permanent networks in Puerto Rico, Haiti, Cuba, the Cayman Islands, and Jamaica to develop a better understanding of the crust and upper mantle structure in the Northeastern Caribbean (Greater Antilles). One important goal of GrASP is to develop robust velocity models that can be used to improve earthquake location and seismic hazard efforts. In this study, we focus on obtaining Rayleigh wave group velocity maps from ambient noise tomography. By cross-correlating ambient seismic noise recorded at 53 stations between 2010 to present, we obtain Green's functions between 1165 pairs of stations. From these, we obtain dispersion curves by the application of FTAN methods with phase-matched filtering. Selection criteria depend on the signal-to-noise ratio and seasonal variability, with further filtering done by rejecting velocities incompatible with maps produced from overdamped tomographic inversions. Preliminary dispersion maps show strong correlations with large-scale geological and tectonic features for periods between 5 - 20 s, such as the Cordillera Central in both the Dominican Republic and Puerto Rico, the Mona Passage, and the NA-CAR subduction zone. Ongoing efforts focus on including shorter periods in Puerto Rico as its denser station distribution could allow us to retrieve higher resolution group velocity maps.

  8. Laser polarization dependent and magnetically control of group velocity in a dielectric medium doped with nanodiamond nitrogen vacancy centers

    Energy Technology Data Exchange (ETDEWEB)

    Asadpour, Seyyed Hossein; Rahimpour Soleimani, H., E-mail: Rahimpour@guilan.ac.ir

    2014-03-01

    In this paper, group velocity control of Gaussian beam in a dielectric medium doped with nanodiamond nitrogen vacancy (NV) centers under optical excitation is discussed. The shape of transmitted and reflected pulses from dielectric can be tuned by changing the intensity of magnetic field and polarization of the control beam. The effect of intensity of control beam on group velocity is also investigated.

  9. On the evolution of magnetic and velocity fields of an originating sunspot group

    International Nuclear Information System (INIS)

    Bachmann, G.

    1978-01-01

    Magnetographic measurements were made to derive longitudinal magnetic field strengths, line-of-sight velocities and the brightness distribution in an originating sunspot group. These results and photographs of the group are used to compare the evaluation of a relatively simple active region with our present ideas about the evolution of active regions in general. We found that the total magnetic flux increased from about 4 to 20x10 20 Mx over three days. The downward flow of gas in regions with stronger magnetic fields is formed only after the magnetic field has already been bipolar for two days. The maximum velocity always occurred in the main spots of the preceding and the subsequent parts of the sunspot group. Transformation into a flow pattern, which looks like Evershed motion, is observed in the main preceding sunspot after the formation of the penumbra. The generation of new active regions by concentration and amplification of magnetic fields, under the action of supergranulation flow in photospheric layers, cannot play an important role. On the contrary, the behaviour of the active region is in agreement with the conception of rising flux tubes, out of which the gas flows down. Our observations confirm that a magnetic field strength, leading to the generation of sunspots, is attained earlier in the preceding part of the originating active region than in its subsequent part. A series of subflares occurred in the active region, when short-lived small magnetic structure elements emerged in the larger bipolar magnetic field. (author)

  10. Interference effects on quantum light group velocity in cavity induced transparency

    International Nuclear Information System (INIS)

    Eilam, Asaf; Thanopulos, Ioannis

    2015-01-01

    We investigate the propagation of a quantized probe field in a dense medium composed of three-level Λ-type systems under cavity electromagnetically induced transparency conditions. We treat the medium as composed of collective states of the three-level systems while the light-medium interaction occurs within clusters of such collective states depending on the photon number state of the probe field. We observe slower group velocity for lower photon number input probe field only under conditions of no interference between different clusters of collective states in the system. (paper)

  11. Quantitative evaluation of standard deviations of group velocity dispersion in optical fibre using parametric amplification

    DEFF Research Database (Denmark)

    Rishøj, Lars Søgaard; Svane, Ask Sebastian; Lund-Hansen, Toke

    2014-01-01

    A numerical model for parametric amplifiers, which include stochastic variations of the group velocity dispersion (GVD), is presented. The impact on the gain is investigated, both with respect to the magnitude of the variations and by the effect caused by changing the wavelength of the pump. It i....... It is demonstrated that the described model is able to predict the experimental results and thereby provide a quantitative evaluation of the standard deviation of the GVD. For the investigated fibre, a standard deviation of 0.01 ps/(nm km) was found....

  12. All-optical control of group velocity dispersion in tellurite photonic crystal fibers.

    Science.gov (United States)

    Liu, Lai; Tian, Qijun; Liao, Meisong; Zhao, Dan; Qin, Guanshi; Ohishi, Yasutake; Qin, Weiping

    2012-12-15

    We demonstrate all-optical control of group velocity dispersion (GVD) via optical Kerr effect in highly nonlinear tellurite photonic crystal fibers. The redshift of the zero-dispersion wavelength is over 307 nm, measured by soliton self-frequency shift cancellation, when the pump peak power of a 1.56 μm femtosecond fiber laser is increased to 11.6 kW. The all-optical control of GVD not only offers a new platform for constructing all-optical-control photonic devices but also promises a new class of experiments in nonlinear fiber optics and light-matter interactions.

  13. Generation of High-order Group-velocity-locked Vector Solitons

    OpenAIRE

    Jin, X. X.; Wu, Z. C.; Zhang, Q.; Li, L.; Tang, D. Y.; Shen, D. Y.; Fu, S. N.; Liu, D. M.; Zhao, L. M.

    2015-01-01

    We report numerical simulations on the high-order group-velocity-locked vector soliton (GVLVS) generation based on the fundamental GVLVS. The high-order GVLVS generated is characterized with a two-humped pulse along one polarization while a single-humped pulse along the orthogonal polarization. The phase difference between the two humps could be 180 degree. It is found that by appropriate setting the time separation between the two components of the fundamental GVLVS, the high-order GVLVS wit...

  14. General analysis of group velocity effects in collinear optical parametric amplifiers and generators.

    Science.gov (United States)

    Arisholm, Gunnar

    2007-05-14

    Group velocity mismatch (GVM) is a major concern in the design of optical parametric amplifiers (OPAs) and generators (OPGs) for pulses shorter than a few picoseconds. By simplifying the coupled propagation equations and exploiting their scaling properties, the number of free parameters for a collinear OPA is reduced to a level where the parameter space can be studied systematically by simulations. The resulting set of figures show the combinations of material parameters and pulse lengths for which high performance can be achieved, and they can serve as a basis for a design.

  15. Effects of spontaneously generated coherence on the group velocity in a V system

    International Nuclear Information System (INIS)

    Bai Yanfeng; Guo Hong; Han, Dingan; Sun Hui

    2005-01-01

    We show how the application of an incoherent pumping can produce a variety of effects on the propagation of a weak electromagnetic pulse in a V system with spontaneously generated coherence (SGC). There exists an incoherent pumping rate which makes the group velocity reach the extremum near the region of two-photon resonant excitation. The existence of SGC is just the cause for the occurrence of the extremum, and it may also be regarded as a knob which can be used to manipulate light propagation from subluminal to superluminal

  16. High-energy radiation from collisions of high-velocity clouds and the Galactic disc

    Science.gov (United States)

    del Valle, Maria V.; Müller, A. L.; Romero, G. E.

    2018-04-01

    High-velocity clouds (HVCs) are interstellar clouds of atomic hydrogen that do not follow normal Galactic rotation and have velocities of a several hundred kilometres per second. A considerable number of these clouds are falling down towards the Galactic disc. HVCs form large and massive complexes, so if they collide with the disc a great amount of energy would be released into the interstellar medium. The cloud-disc interaction produces two shocks: one propagates through the cloud and the other through the disc. The properties of these shocks depend mainly on the cloud velocity and the disc-cloud density ratio. In this work, we study the conditions necessary for these shocks to accelerate particles by diffusive shock acceleration and we study the non-thermal radiation that is produced. We analyse particle acceleration in both the cloud and disc shocks. Solving a time-dependent two-dimensional transport equation for both relativistic electrons and protons, we obtain particle distributions and non-thermal spectral energy distributions. In a shocked cloud, significant synchrotron radio emission is produced along with soft gamma rays. In the case of acceleration in the shocked disc, the non-thermal radiation is stronger; the gamma rays, of leptonic origin, might be detectable with current instruments. A large number of protons are injected into the Galactic interstellar medium, and locally exceed the cosmic ray background. We conclude that under adequate conditions the contribution from HVC-disc collisions to the galactic population of relativistic particles and the associated extended non-thermal radiation might be important.

  17. Corrosion and erosion monitoring in plates and pipes using constant group velocity Lamb wave inspection.

    Science.gov (United States)

    Nagy, Peter B; Simonetti, Francesco; Instanes, Geir

    2014-09-01

    Recent improvements in tomographic reconstruction techniques generated a renewed interest in short-range ultrasonic guided wave inspection for real-time monitoring of internal corrosion and erosion in pipes and other plate-like structures. Emerging evidence suggests that in most cases the fundamental asymmetric A0 mode holds a distinct advantage over the earlier market leader fundamental symmetric S0 mode. Most existing A0 mode inspections operate at relatively low inspection frequencies where the mode is highly dispersive therefore very sensitive to variations in wall thickness. This paper examines the potential advantages of increasing the inspection frequency to the so-called constant group velocity (CGV) point where the group velocity remains essentially constant over a wide range of wall thickness variation, but the phase velocity is still dispersive enough to allow accurate wall thickness assessment from phase angle measurements. This paper shows that in the CGV region the crucial issue of temperature correction becomes especially simple, which is particularly beneficial when higher-order helical modes are also exploited for tomography. One disadvantage of working at such relatively high inspection frequency is that, as the slower A0 mode becomes faster and less dispersive, the competing faster S0 mode becomes slower and more dispersive. At higher inspection frequencies these modes cannot be separated any longer based on their vibration polarization only, which is mostly tangential for the S0 mode while mostly normal for the A0 at low frequencies, as the two modes become more similar as the frequency increases. Therefore, we propose a novel method for suppressing the unwanted S0 mode based on the Poisson effect of the material by optimizing the angle of inclination of the equivalent transduction force of the Electromagnetic Acoustic Transducers (EMATs) used for generation and detection purposes. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Anomalous group velocity at the high energy range of real 3D photonic nanostructures

    Science.gov (United States)

    Botey, Muriel; Martorell, Jordi; Lozano, Gabriel; Míguez, Hernán; Dorado, Luis A.; Depine, Ricardo A.

    2010-05-01

    We perform a theoretical study on the group velocity for finite thin artificial opal slabs made of a reduced number of layers in the spectral range where the light wavelength is on the order of the lattice parameter. The vector KKR method including extinction allows us to evaluate the finite-size effects on light propagation in the ΓL and ΓX directions of fcc close-packed opal films made of dielectric spheres. The group is index determined from the phase delay introduced by the structure to the forwardly transmitted electric field. We show that for certain frequencies, light propagation can either be superluminal -positive or negative- or approach zero depending on the crystal size and absorption. Such anomalous behavior can be attributed to the finite character of the structure and provides confirmation of recently emerged experimental results.

  19. Rayleigh Wave Group Velocity Tomography from Microseisms in the Acambay Graben

    Science.gov (United States)

    Valderrama Membrillo, S.; Aguirre, J.; Zuñiga-Davila, R.; Iglesias, A.

    2017-12-01

    The Acambay graben is one of the most outstanding structures of the Trans-Mexican Volcanic Belt. The Acambay graben has a length of 80km and 15 to 18 km wide and reaches a maximum height of 400 m in its central part. We obtained the group velocity seismic tomography for the Acamaby graben for three different frequencies (f = 0.1, 0.2 and 0.3 Hz). The graben was divided into 6x6 km cells for the tomography and covered a total area of 1008 km2. Seismic noise data from 10 broadband seismic stations near the Acambay graben were used to extract the surface wave arrival-times between all station pairs. The Green's function was recovered in each stations pair by cross-correlation technique. This technique was applied to seismic recordings collected on the vertical component of 10 broadband stations for a continuous recording period of 5 months. Data processing consisted of removing instrumental response, mean, and trend. After that, we applied time domain normalization, a spectral whitening and applied band-pas filtering of 0.1 to 1 Hz. There are shallow studies of the Acambay graben. But little is known of the distribution of deep graben structures. This study estimated the surface wave velocity deep structure. The structures at the frequency 0.3 Hz indicate a lower depth than the remaining frequencies. The result for this frequency show consistencies with previous studies of gravimetry and resistivity, also defines the fault system of Temascalcingo.

  20. A First Layered Crustal Velocity Model for the Western Solomon Islands: Inversion of Measured Group Velocity of Surface Waves using Ambient Noise Cross-Correlation

    Science.gov (United States)

    Ku, C. S.; Kuo, Y. T.; Chao, W. A.; You, S. H.; Huang, B. S.; Chen, Y. G.; Taylor, F. W.; Yih-Min, W.

    2017-12-01

    Two earthquakes, MW 8.1 in 2007 and MW 7.1 in 2010, hit the Western Province of Solomon Islands and caused extensive damage, but motivated us to set up the first seismic network in this area. During the first phase, eight broadband seismic stations (BBS) were installed around the rupture zone of 2007 earthquake. With one-year seismic records, we cross-correlated the vertical component of ambient noise recorded in our BBS and calculated Rayleigh-wave group velocity dispersion curves on inter-station paths. The genetic algorithm to invert one-dimensional crustal velocity model is applied by fitting the averaged dispersion curves. The one-dimensional crustal velocity model is constituted by two layers and one half-space, representing the upper crust, lower crust, and uppermost mantle respectively. The resulted thickness values of the upper and lower crust are 6.4 and 14.2 km, respectively. Shear-wave velocities (VS) of the upper crust, lower crust, and uppermost mantle are 2.53, 3.57 and 4.23 km/s with the VP/VS ratios of 1.737, 1.742 and 1.759, respectively. This first layered crustal velocity model can be used as a preliminary reference to further study seismic sources such as earthquake activity and tectonic tremor.

  1. Lithospheric structure of the Arabian Shield and Platform from complete regional waveform modelling and surface wave group velocities

    Science.gov (United States)

    Rodgers, Arthur J.; Walter, William R.; Mellors, Robert J.; Al-Amri, Abdullah M. S.; Zhang, Yu-Shen

    1999-09-01

    Regional seismic waveforms reveal significant differences in the structure of the Arabian Shield and the Arabian Platform. We estimate lithospheric velocity structure by modelling regional waveforms recorded by the 1995-1997 Saudi Arabian Temporary Broadband Deployment using a grid search scheme. We employ a new method whereby we narrow the waveform modelling grid search by first fitting the fundamental mode Love and Rayleigh wave group velocities. The group velocities constrain the average crustal thickness and velocities as well as the crustal velocity gradients. Because the group velocity fitting is computationally much faster than the synthetic seismogram calculation this method allows us to determine good average starting models quickly. Waveform fits of the Pn and Sn body wave arrivals constrain the mantle velocities. The resulting lithospheric structures indicate that the Arabian Platform has an average crustal thickness of 40 km, with relatively low crustal velocities (average crustal P- and S-wave velocities of 6.07 and 3.50 km s^-1 , respectively) without a strong velocity gradient. The Moho is shallower (36 km) and crustal velocities are 6 per cent higher (with a velocity increase with depth) for the Arabian Shield. Fast crustal velocities of the Arabian Shield result from a predominantly mafic composition in the lower crust. Lower velocities in the Arabian Platform crust indicate a bulk felsic composition, consistent with orogenesis of this former active margin. P- and S-wave velocities immediately below the Moho are slower in the Arabian Shield than in the Arabian Platform (7.9 and 4.30 km s^-1 , and 8.10 and 4.55 km s^-1 , respectively). This indicates that the Poisson's ratios for the uppermost mantle of the Arabian Shield and Platform are 0.29 and 0.27, respectively. The lower mantle velocities and higher Poisson's ratio beneath the Arabian Shield probably arise from a partially molten mantle associated with Red Sea spreading and continental

  2. Group-velocity dispersion effects on quantum noise of a fiber optical soliton in phase space

    International Nuclear Information System (INIS)

    Ju, Heongkyu; Lee, Euncheol

    2010-01-01

    Group-velocity dispersion (GVD) effects on quantum noise of ultrashort pulsed light are theoretically investigated at the soliton energy level, using Gaussian-weighted pseudo-random distribution of phasors in phase space for the modeling of quantum noise properties including phase noise, photon number noise, and quantum noise shape in phase space. We present the effects of GVD that mixes the different spectral components in time, on the self-phase modulation(SPM)-induced quantum noise properties in phase space such as quadrature squeezing, photon-number noise, and tilting/distortion of quantum noise shape in phase space, for the soliton that propagates a distance of the nonlinear length η NL = 1/( γP 0 ) (P 0 is the pulse peak power and γ is the SPM parameter). The propagation dependence of phase space quantum noise properties for an optical soliton is also provided.

  3. Dynamical diffusion and renormalization group equation for the Fermi velocity in doped graphene

    International Nuclear Information System (INIS)

    Ardenghi, J.S.; Bechthold, P.; Jasen, P.; Gonzalez, E.; Juan, A.

    2014-01-01

    The aim of this work is to study the electron transport in graphene with impurities by introducing a generalization of linear response theory for linear dispersion relations and spinor wave functions. Current response and density response functions are derived and computed in the Boltzmann limit showing that in the former case a minimum conductivity appears in the no-disorder limit. In turn, from the generalization of both functions, an exact relation can be obtained that relates both. Combining this result with the relation given by the continuity equation it is possible to obtain general functional behavior of the diffusion pole. Finally, a dynamical diffusion is computed in the quasistatic limit using the definition of relaxation function. A lower cutoff must be introduced to regularize infrared divergences which allow us to obtain a full renormalization group equation for the Fermi velocity, which is solved up to order O(ℏ 2 )

  4. Angular beam width of a slit-diffracted wave with noncollinear group and phase velocities

    International Nuclear Information System (INIS)

    Lock, Edwin H

    2012-01-01

    Taking magnetostatic surface wave diffraction as an example, this paper theoretically investigates the 2D diffraction pattern arising in the far-field region of a ferrite slab in the case of a plane wave with noncollinear group and phase velocities incident on a wide, arbitrarily oriented slit in an opaque screen. A universal analytical formula for the angular width of a diffracted beam is derived, which is valid for magnetostatic and other types of waves in anisotropic media and structures (including metamaterials) in 2D geometries. It is shown that the angular width of a diffracted beam in an anisotropic medium can not only take values greater or less than λ 0 /D (where λ 0 is the incident wavelength, and D is the slit width), but can also be zero under certain conditions. (methodological notes)

  5. Controllable group velocity of the probe light in a Λ-type system with two fold levels

    International Nuclear Information System (INIS)

    Jin Lihui; Gong Shangqing; Niu Yueping; Li Ruxin; Jin Shiqi

    2006-01-01

    The group velocities of the probe laser field are studied in a Λ-type system where one lower state has two fold levels coupled by a control field. It is found that the interaction of double dark states leads to controllable group velocity of the probe field in this system. It can be easily realized, due to the interacting double dark resonances, that one of the group velocities at transparency positions is much slower than the other by tuning the control field to be off resonance. In particular, when the control field is on resonance, we can obtain two equal slow group velocities with a broader EIT width, which provides potential applications in quantum storage and retrieval of light

  6. Crust and upper mantle structure in the Caribbean region by group velocity tomography and regionalization

    International Nuclear Information System (INIS)

    O'Leary, Gonzalez; Alvarez, L.; Chimera, G.; Panza, G.F.

    2004-04-01

    An overview of the crust and upper mantle structure of the Central America and Caribbean region is presented as a result of the processing of more than 200 seismograms recorded by digital broadband stations from SSSN and GSN seismic networks. By FTAN analysis of the fundamental mode of the Rayleigh waves, group velocity dispersion curves are obtained in the period range from 10 s to 40 s; the error of these measurements varies from 0.06 and 0.10 km/s. From the dispersion curves, seven tomographic maps at different periods and with average spatial resolution of 500 km are obtained. Using the logical combinatorial classification techniques, eight main groups of dispersion curves are determined from the tomographic maps and eleven main regions, each one characterized by one kind of dispersion curves, are identified. The average dispersion curves obtained for each region are extended to 150 s by adding data from the tomographic study of and inverted using a non-linear procedure. As a result of the inversion process, a set of models of the S-wave velocity vs. depth in the crust and upper mantle are found. In six regions, we identify a typically oceanic crust and upper mantle structure, while in the other two the models are consistent with the presence of a continental structure. Two regions, located over the major geological zones of the accretionary crust of the Caribbean region, are characterized by a peculiar crust and upper mantle structure, indicating the presence of lithospheric roots reaching, at least, about 200 km of depth. (author)

  7. The 1994 Northridge, California, earthquake: Investigation of rupture velocity, risetime, and high-frequency radiation

    Science.gov (United States)

    Hartzell, S.; Liu, P.; Mendoza, C.

    1996-01-01

    A hybrid global search algorithm is used to solve the nonlinear problem of calculating slip amplitude, rake, risetime, and rupture time on a finite fault. Thirty-five strong motion velocity records are inverted by this method over the frequency band from 0.1 to 1.0 Hz for the Northridge earthquake. Four regions of larger-amplitude slip are identified: one near the hypocenter at a depth of 17 km, a second west of the hypocenter at about the same depth, a third updip from the hypocenter at a depth of 10 km, and a fourth updip from the hypocenter and to the northwest. The results further show an initial fast rupture with a velocity of 2.8 to 3.0 km/s followed by a slow termination of the rupture with velocities of 2.0 to 2.5 km/s. The initial energetic rupture phase lasts for 3 s, extending out 10 km from the hypocenter. Slip near the hypocenter has a short risetime of 0.5 s, which increases to 1.5 s for the major slip areas removed from the hypocentral region. The energetic rupture phase is also shown to be the primary source of high-frequency radiation (1-15 Hz) by an inversion of acceleration envelopes. The same global search algorithm is used in the envelope inversion to calculate high-frequency radiation intensity on the fault and rupture time. The rupture timing from the low- and high-frequency inversions is similar, indicating that the high frequencies are produced primarily at the mainshock rupture front. Two major sources of high-frequency radiation are identified within the energetic rupture phase, one at the hypocenter and another deep source to the west of the hypocenter. The source at the hypocenter is associated with the initiation of rupture and the breaking of a high-stress-drop asperity and the second is associated with stopping of the rupture in a westerly direction.

  8. Medical Managment of the Acute Radiation Syndrome: Recommendations of the Strategic National Stockpile Radiation Working Group

    National Research Council Canada - National Science Library

    Waselenka, Jamie K; MacVittie, Thomas J; Blakely, William F; Pesik, Nicki; Wiley, Albert L; Dickerson, William E; Tsu, Horace; Confer, Dennis L; Coleman, Norman; Seed, Thomas

    2004-01-01

    .... This consensus document was developed by the Strategic National Stockpile Radiation Working Group to provide a framework for physicians in internal medicine and the medical subspecialties to evaluate...

  9. Risk management of radiation therapy. Survey by north Japan radiation therapy oncology group

    International Nuclear Information System (INIS)

    Aoki, Masahiko; Abe, Yoshinao; Yamada, Shogo; Hareyama, Masato; Nakamura, Ryuji; Sugita, Tadashi; Miyano, Takashi

    2004-01-01

    A North Japan Radiation Oncology Group (NJRTOG) survey was carried out to disclose the risk management of radiation therapy. During April 2002, we sent questionnaires to radiation therapy facilities in northern Japan. There were 31 replies from 27 facilities. Many incidents and accidents were reported, including old cases. Although 60% of facilities had a risk management manual and/or risk manager, only 20% had risk management manuals for radiation therapy. Eighty five percent of radiation oncologists thought that incidents may be due to a lack of manpower. Ninety percent of radiation oncologists want to know the type of cases happened in other facilities. The risk management system is still insufficient for radiation therapy. We hope that our data will be a great help to develop risk management strategies for radiation therapy for all radiation oncologists in Japan. (author)

  10. Tomographic Rayleigh wave group velocities in the Central Valley, California, centered on the Sacramento/San Joaquin Delta

    Science.gov (United States)

    Fletcher, Jon B.; Erdem, Jemile; Seats, Kevin; Lawrence, Jesse

    2016-04-01

    If shaking from a local or regional earthquake in the San Francisco Bay region were to rupture levees in the Sacramento/San Joaquin Delta, then brackish water from San Francisco Bay would contaminate the water in the Delta: the source of freshwater for about half of California. As a prelude to a full shear-wave velocity model that can be used in computer simulations and further seismic hazard analysis, we report on the use of ambient noise tomography to build a fundamental mode, Rayleigh wave group velocity model for the region around the Sacramento/San Joaquin Delta in the western Central Valley, California. Recordings from the vertical component of about 31 stations were processed to compute the spatial distribution of Rayleigh wave group velocities. Complex coherency between pairs of stations was stacked over 8 months to more than a year. Dispersion curves were determined from 4 to about 18 s. We calculated average group velocities for each period and inverted for deviations from the average for a matrix of cells that covered the study area. Smoothing using the first difference is applied. Cells of the model were about 5.6 km in either dimension. Checkerboard tests of resolution, which are dependent on station density, suggest that the resolving ability of the array is reasonably good within the middle of the array with resolution between 0.2 and 0.4°. Overall, low velocities in the middle of each image reflect the deeper sedimentary syncline in the Central Valley. In detail, the model shows several centers of low velocity that may be associated with gross geologic features such as faulting along the western margin of the Central Valley, oil and gas reservoirs, and large crosscutting features like the Stockton arch. At shorter periods around 5.5 s, the model's western boundary between low and high velocities closely follows regional fault geometry and the edge of a residual isostatic gravity low. In the eastern part of the valley, the boundaries of the low-velocity

  11. Tomographic Rayleigh-wave group velocities in the Central Valley, California centered on the Sacramento/San Joaquin Delta

    Science.gov (United States)

    Fletcher, Jon Peter B.; Erdem, Jemile; Seats, Kevin; Lawrence, Jesse

    2016-01-01

    If shaking from a local or regional earthquake in the San Francisco Bay region were to rupture levees in the Sacramento/San Joaquin Delta then brackish water from San Francisco Bay would contaminate the water in the Delta: the source of fresh water for about half of California. As a prelude to a full shear-wave velocity model that can be used in computer simulations and further seismic hazard analysis, we report on the use of ambient noise tomography to build a fundamental-mode, Rayleigh-wave group velocity model for the region around the Sacramento/San Joaquin Delta in the western Central Valley, California. Recordings from the vertical component of about 31 stations were processed to compute the spatial distribution of Rayleigh wave group velocities. Complex coherency between pairs of stations were stacked over 8 months to more than a year. Dispersion curves were determined from 4 to about 18 seconds. We calculated average group velocities for each period and inverted for deviations from the average for a matrix of cells that covered the study area. Smoothing using the first difference is applied. Cells of the model were about 5.6 km in either dimension. Checkerboard tests of resolution, which is dependent on station density, suggest that the resolving ability of the array is reasonably good within the middle of the array with resolution between 0.2 and 0.4 degrees. Overall, low velocities in the middle of each image reflect the deeper sedimentary syncline in the Central Valley. In detail, the model shows several centers of low velocity that may be associated with gross geologic features such as faulting along the western margin of the Central Valley, oil and gas reservoirs, and large cross cutting features like the Stockton arch. At shorter periods around 5.5s, the model’s western boundary between low and high velocities closely follows regional fault geometry and the edge of a residual isostatic gravity low. In the eastern part of the valley, the boundaries

  12. Fourier analysis of cerebrospinal fluid flow velocities: MR imaging study. The Scandinavian Flow Group

    DEFF Research Database (Denmark)

    Thomsen, C; Ståhlberg, F; Stubgaard, M

    1990-01-01

    images. The phase information in the resultant image was converted to flow velocity with a calibration curve with the slope 26.5 radian.m-1.sec. The velocity versus time function was Fourier transformed and a continuous curve was fitted to the measured data with use of the first three harmonics...

  13. Working Group on Ionising Radiations. Report 1987-88

    International Nuclear Information System (INIS)

    1989-01-01

    The programme of work for 1987/88 by the Working Group on Ionising Radiation, Health and Safety Commision in February 1988, included the main topics of continuing interest and concern in relation to ionising radiations in general and the Ionising Radiations Regulations 1985 (IRR 85) (Ref 1) in particular. These were: emergency dose limitation, occupational dose limitation, practical experience of the principle of keeping doses as low as reasonably practicable, experience of the regulatory requirements in respect of internal dosimetry and the need for a standing advisory committee on ionising radiations. Calibration of radiotherapy equipment was also considered as a matter of principle following a specific incident involving cancer patients. This report of progress during the first year summarises the Group's opinions on each topic and gives recommendations. (author)

  14. Pitfalls in velocity analysis for strongly contrasting, layered media - Example from the Chalk Group, North Sea

    Science.gov (United States)

    Montazeri, Mahboubeh; Uldall, Anette; Moreau, Julien; Nielsen, Lars

    2018-02-01

    Knowledge about the velocity structure of the subsurface is critical in key seismic processing sequences, for instance, migration, depth conversion, and construction of initial P- and S-wave velocity models for full-waveform inversion. Therefore, the quality of subsurface imaging is highly dependent upon the quality of the seismic velocity analysis. Based on a case study from the Danish part of the North Sea, we show how interference caused by multiples, converted waves, and thin-layer effects may lead to incorrect velocity estimation, if such effects are not accounted for. Seismic wave propagation inside finely layered reservoir rocks dominated by chalk is described by two-dimensional finite-difference wave field simulation. The rock physical properties used for the modeling are based on an exploration well from the Halfdan field in the Danish sector of the North Sea. The modeling results are compared to seismic data from the study area. The modeling shows that interference of primaries with multiples, converted waves and thin-bed effects can give rise to strong anomalies in standard velocity analysis plots. Consequently, root-mean-square (RMS) velocity profiles may be erroneously picked. In our study area, such mis-picking can introduce errors in, for example, the thickness estimation of the layers near the base of the studied sedimentary strata by 11% to 26%. Tests show that front muting and bandpass filtering cannot significantly improve the quality of velocity analysis in our study. However, we notice that spiking deconvolution applied before velocity analysis may to some extent reduce the impact of interference and, therefore, reduce the risk of erroneous picking of the velocity function.

  15. Group consensus peer review in radiation oncology: commitment to quality.

    Science.gov (United States)

    Duggar, W Neil; Bhandari, Rahul; Yang, Chunli Claus; Vijayakumar, Srinivasan

    2018-03-27

    Peer review, especially prospective peer review, has been supported by professional organizations as an important element in optimal Radiation Oncology practice based on its demonstration of efficacy at detecting and preventing errors prior to patient treatment. Implementation of peer review is not without barriers, but solutions do exist to mitigate or eliminate some of those barriers. Peer review practice at our institution involves three key elements: new patient conference, treatment planning conference, and chart rounds. The treatment planning conference is an adaptation of the group consensus peer review model from radiology which utilizes a group of peers reviewing each treatment plan prior to implementation. The peer group in radiation oncology includes Radiation Oncologists, Physician Residents, Medical Physicists, Dosimetrists, and Therapists. Thus, technical and clinical aspects of each plan are evaluated simultaneously. Though peer review is held in high regard in Radiation Oncology, many barriers commonly exist preventing optimal implementation such as time intensiveness, repetition, and distraction from clinic time with patients. Through the use of automated review tools and commitment by individuals and administration in regards to staffing, scheduling, and responsibilities, these barriers have been mitigated to implement this Group Consensus Peer Review model into a Radiation Oncology Clinic. A Group Consensus Peer Review model has been implemented with strategies to address common barriers to effective and efficient peer review.

  16. Cyclotron radiation by a multi-group method

    International Nuclear Information System (INIS)

    Chu, T.C.

    1980-01-01

    A multi-energy group technique is developed to study conditions under which cyclotron radiation emission can shift a Maxwellian electron distribution into a non-Maxwellian; and if the electron distribution is non-Maxwellian, to study the rate of cyclotron radiation emission as compared to that emitted by a Maxwellian having the same mean electron density and energy. The assumptions in this study are: the electrons should be in an isotropic medium and the magnetic field should be uniform. The multi-group technique is coupled into a multi-group Fokker-Planck computer code to study electron behavior under the influence of cyclotron radiation emission in a self-consistent fashion. Several non-Maxwellian distributions were simulated to compare their cyclotron emissions with the corresponding energy and number density equivalent Maxwellian distribtions

  17. Reflection Group on 'Ethical Choices in Radiation Protection'

    International Nuclear Information System (INIS)

    Eggermont, G.

    2000-01-01

    As part of SCK-CEN's social sciences and humanities programme, a reflection group on 'Ethical Choices in Radiation Protection' was created. The objectives of the reflection group are (1) to brainstorm on critical issues of radiation protection; (2) to create a discussion forum with a variety os SCK-CEN researchers and external experts; (3) to make value judgements and open questions in radiation protection explicit; (4) to create an output for a topical day or workshop by editing a 'cahier' of contributed articles and discussion reports; (5) to complement the output of the SCK-CEN contribution in international ALARA workshops. The programme, achievements and perspectives of the refection group are summarised

  18. On excitation and radiation of detector moving in vacuum with acceleration or moving rectilinearly with superluminal velocity in a medium

    International Nuclear Information System (INIS)

    Ginzburg, V.L.; Frolov, V.P.

    1986-01-01

    The problem of excitation of a detector moving in vacuum with constant acceleration is being discussed in recent years. It is noted in the paper that this excitation and radiation associated with it are similar to those taking place in the range of anomalous Doppler effect occurring during motion of the detector with constant superluminal velocity in medium

  19. Perception of radiation related risks among three population groups

    International Nuclear Information System (INIS)

    Mihai, L.T.; Milu, C.; Voicu, B.; Enachescu, D.

    2003-01-01

    A questionnaire survey was conducted among three groups that mainly differ in socioeconomic status and professional exposure to ionizing radiations. Seventy-seven (26.3%) of the respondents were professionally exposed to radiation, 35 (11.9%) were medical doctors without professional exposure and 177 (68.4%) belonged to the general population group. The level of anxiety toward radiation, expressed as a concernedness index, is significantly lower in people who are professionally exposed to radiation compared to medical doctors and general population (0.81±0.94, 1.42±1.21 and 1.72±1.34 respectively, p < 0.001). In a similar manner, concernedness index values varied with the education status, with lowest values among medical university graduates and highest among public school graduates (p < 0.001). Both university-graduated groups significantly differ from the non-university groups (p < 0.05). Knowledge about radiation and knowledge about emergency plans in nuclear accident/incident were also checked in relation with concernedness, the results confirming the hypothesis that better knowledge associates lower concernedness. The extent to which people accept the civil utilization of nuclear power is also related to concernedness and knowledge, significant associations having been found. The results suggest that a political decision in radiation matter requires a valid analysis of the public's understanding and acceptance. For that reason, it is important that radiological protection authorities develop new plans and materials for communicating with people, in order to improve knowledge upon ionizing radiation, irradiation risks and safety of nuclear energy application for civil purposes. (author)

  20. Ultra-compact high velocity clouds in the ALFALFA HI survey: Candidate Local Group galaxies?

    Science.gov (United States)

    Adams, Elizabeth Ann Kovenz

    The increased sensitivity and spatial resolution of the ALFALFA HI survey has resulted in the detection of ultra-compact high velocity clouds (UCHVCs). These objects are good candidates to represent low mass gas-rich galaxies in the Local Group and Local Volume with stellar populations that are too faint to be detected in extant optical surveys. This idea is referred to as the "minihalo hypothesis". We identify the UCHVCs within the ALFALFA dataset via the use of a 3D matched filtering signal identification algorithm. UCHVCs are selected based on a compact size ( 120 km s-1) and isolation. Within the 40% complete ALFALFA survey (alpha.40), 59 UCHVCs are identified; 19 are in a most-isolated subset and are the best galaxy candidates. Due to the presence of large HVC complexes in the fall sky, most notably the Magellanic Stream, the association of UCHVCs with existing structure cannot be ruled out. In the spring sky, the spatial and kinematic distribution of the UCHVCs is consistent with simulations of dark matter halos within the Local Group. In addition, the HI properties of the UCHVCs (if placed at 1 Mpc) are consistent with both theoretical and observational predictions for low mass gas-rich galaxies. Importantly, the HI properties of the UCHVCs are consistent with those of two recently discovered low mass gas-rich galaxies in the Local Group and Local Volume, Leo T and Leo P. Detailed follow-up observations are key for addressing the minihalo hypothesis. High resolution HI observations can constrain the environment of a UCHVC and offer evidence for a hosting dark matter halo through evidence of rotation support and comparison to theoretical models. Observations of one UCHVC at high resolution (15'') reveal the presence of a clumpy HI distribution, similar to both low mass galaxies and circumgalactic compact HVCs. An extended envelope containing ˜50% of the HI flux is resolved out by the array configuration; observations at lower spatial resolution can recover

  1. Crust and uppermost-mantle structure of Greenland and the Northwest Atlantic from Rayleigh wave group velocity tomography

    Science.gov (United States)

    Darbyshire, Fiona A.; Dahl-Jensen, Trine; Larsen, Tine B.; Voss, Peter H.; Joyal, Guillaume

    2018-03-01

    The Greenland landmass preserves ˜4 billion years of tectonic history, but much of the continent is inaccessible to geological study due to the extensive inland ice cap. We map out, for the first time, the 3-D crustal structure of Greenland and the NW Atlantic ocean, using Rayleigh wave anisotropic group velocity tomography, in the period range 10-80 s, from regional earthquakes and the ongoing GLATIS/GLISN seismograph networks. 1-D inversion gives a pseudo-3-D model of shear wave velocity structure to depths of ˜100 km with a horizontal resolution of ˜200 km. Crustal thickness across mainland Greenland ranges from ˜25 km to over 50 km, and the velocity structure shows considerable heterogeneity. The large sedimentary basins on the continental shelf are clearly visible as low velocities in the upper ˜5-15 km. Within the upper continental basement, velocities are systematically lower in northern Greenland than in the south, and exhibit a broadly NW-SE trend. The thinning of the crust at the continental margins is also clearly imaged. Upper-mantle velocities show a clear distinction between typical fast cratonic lithosphere (Vs ≥4.6 km s-1) beneath Greenland and its NE margin and anomalously slow oceanic mantle (Vs ˜4.3-4.4 km s-1) beneath the NW Atlantic. We do not observe any sign of pervasive lithospheric modification across Greenland in the regions associated with the presumed Iceland hotspot track, though the average crustal velocity in this region is higher than that of areas to the north and south. Crustal anisotropy beneath Greenland is strong and complex, likely reflecting numerous episodes of tectonic deformation. Beneath the North Atlantic and Baffin Bay, the dominant anisotropy directions are perpendicular to the active and extinct spreading centres. Anisotropy in the subcontinental lithosphere is weaker than that of the crust, but still significant, consistent with cratonic lithosphere worldwide.

  2. Experimental validation of alternate integral-formulation method for predicting acoustic radiation based on particle velocity measurements.

    Science.gov (United States)

    Ni, Zhi; Wu, Sean F

    2010-09-01

    This paper presents experimental validation of an alternate integral-formulation method (AIM) for predicting acoustic radiation from an arbitrary structure based on the particle velocities specified on a hypothetical surface enclosing the target source. Both the normal and tangential components of the particle velocity on this hypothetical surface are measured and taken as the input to AIM codes to predict the acoustic pressures in both exterior and interior regions. The results obtained are compared with the benchmark values measured by microphones at the same locations. To gain some insight into practical applications of AIM, laser Doppler anemometer (LDA) and double hotwire sensor (DHS) are used as measurement devices to collect the particle velocities in the air. Measurement limitations of using LDA and DHS are discussed.

  3. Crustal structure beneath discovery bank in the South Scotia Sea from group velocity tomography and seismic reflection data

    International Nuclear Information System (INIS)

    Vuan, A.; Lodolo, E.; Panza, G.F.

    2003-09-01

    Bruce, Discovery, Herdman and Jane Banks, all located along the central-eastern part of the South Scotia Ridge (i.e., the Antarctica-Scotia plate boundary), represent isolated topographic reliefs surrounded by relatively young oceanic crust, whose petrological and structural nature is still the subject of speculations due to the lack of resolving data. In the Scotia Sea and surrounding regions negative anomalies of about 34% are reported in large-scale group velocity tomography maps. The spatial resolution (∼500 km) of these maps does not warrant any reliable interpretation of such anomalies. A recent surface wave tomography in the same area, performed using broad band seismic stations and 300 regional events, shows that in the period range from 15 s to 50 s the central-eastern part of the South Scotia Ridge is characterized by negative anomalies of the group velocities as large as 6. The resolution of our data set (∼300 km) makes it possible to distinguish an area (centered at 61 deg S and 36 deg W) with a crust thicker than 25 km, and a shear wave velocity vs. depth profile similar to that found beneath the northern tip of the Antarctic Peninsula and southern South America. Rayleigh and Love wave dispersion curves are inverted in the period range from 15 s to 80 s to obtain shear wave velocity profiles that suggest a continental nature of Discovery Bank. The continental-type crust of this topographic relief is in agreement with the interpretation of a multi-channel seismic reflection profile acquired across this rise. Peculiar acoustic facies are observed in this profile and are interpreted as thinned and faulted continental plateau. The boundaries of the negative group velocity anomalies are marked by a high seismicity rate. Historical normal faulting earthquakes with magnitude around 7 are localised between the low velocity anomaly region in the eastern South Scotia Ridge and the high velocity anomaly region associated with the surrounding oceanic crust

  4. The control of superluminal group velocity in a system equivalent to the Y-type four-level atomic system

    International Nuclear Information System (INIS)

    Li Luming; Guo Hong; Xiao Feng; Peng Xiang; Chen Xuzong

    2005-01-01

    We study a new way to control the superluminal group velocity of light pulse in hot atomic gases with the five-level atomic configuration. The model of an equivalent Y-type four-level is applied and shows that the light goes faster by using an additional incoherent pumping field. The experiment is performed and shows in good agreement with our theoretical predictions

  5. Coherent control of the group velocity in a dielectric slab doped with duplicated two-level atoms

    Science.gov (United States)

    Ziauddin; Chuang, You-Lin; Lee, Ray-Kuang; Qamar, Sajid

    2016-01-01

    Coherent control of reflected and transmitted pulses is investigated theoretically through a slab doped with atoms in a duplicated two-level configuration. When a strong control field and a relatively weak probe field are employed, coherent control of the group velocity is achieved via changing the phase shift ϕ between control and probe fields. Furthermore, the peak values in the delay time of the reflected and transmitted pulses are also studied by varying the phase shift ϕ.

  6. Radiation polymerisable compositions containing 3-sorboyloxy-2-hydroxypropyl groups

    International Nuclear Information System (INIS)

    Green, G.E.

    1976-01-01

    Compounds having at least three 3-sorboyloxy-2-hydroxypropyl groups directly attached to ether oxygen atoms are polymerised by exposure to actinic radiation, preferably in the presence of a sensitizer such as Michler's ketone or benzoin. The compounds may be obtained by the reaction either of sorbic acid with a substance having at least three glycidyl ether groups or of glycidyl sorbate with a substance having at least three phenolic or alcoholic hydroxyl groups: if desired, not all of the glycidyl groups may be consumed, so that, after actinically induced polymerisation, the epoxide-containing polymer may be cross-linked by reaction with a curing agent for epoxide resins. The compounds are useful in making printed circuits or printing plates for offset printing

  7. Acoustic radiation force impulse elastography of the kidneys: is shear wave velocity affected by tissue fibrosis or renal blood flow?

    Science.gov (United States)

    Asano, Kenichiro; Ogata, Ai; Tanaka, Keiko; Ide, Yoko; Sankoda, Akiko; Kawakita, Chieko; Nishikawa, Mana; Ohmori, Kazuyoshi; Kinomura, Masaru; Shimada, Noriaki; Fukushima, Masaki

    2014-05-01

    The aim of this study was to identify the main influencing factor of the shear wave velocity (SWV) of the kidneys measured by acoustic radiation force impulse elastography. The SWV was measured in the kidneys of 14 healthy volunteers and 319 patients with chronic kidney disease. The estimated glomerular filtration rate was calculated by the serum creatinine concentration and age. As an indicator of arteriosclerosis of large vessels, the brachial-ankle pulse wave velocity was measured in 183 patients. Compared to the degree of interobserver and intraobserver deviation, a large variance of SWV values was observed in the kidneys of the patients with chronic kidney disease. Shear wave velocity values in the right and left kidneys of each patient correlated well, with high correlation coefficients (r = 0.580-0.732). The SWV decreased concurrently with a decline in the estimated glomerular filtration rate. A low SWV was obtained in patients with a high brachial-ankle pulse wave velocity. Despite progression of renal fibrosis in the advanced stages of chronic kidney disease, these results were in contrast to findings for chronic liver disease, in which progression of hepatic fibrosis results in an increase in the SWV. Considering that a high brachial-ankle pulse wave velocity represents the progression of arteriosclerosis in the large vessels, the reduction of elasticity succeeding diminution of blood flow was suspected to be the main influencing factor of the SWV in the kidneys. This study indicates that diminution of blood flow may affect SWV values in the kidneys more than the progression of tissue fibrosis. Future studies for reducing data variance are needed for effective use of acoustic radiation force impulse elastography in patients with chronic kidney disease.

  8. Structure of the crust beneath Cameroon, West Africa, from the joint inversion of Rayleigh wave group velocities and receiver functions

    Science.gov (United States)

    Tokam, Alain-Pierre K.; Tabod, Charles T.; Nyblade, Andrew A.; Julià, Jordi; Wiens, Douglas A.; Pasyanos, Michael E.

    2010-11-01

    The Cameroon Volcanic Line (CVL) consists of a linear chain of Tertiary to Recent, generally alkaline, volcanoes that do not exhibit an age progression. Here we study crustal structure beneath the CVL and adjacent regions in Cameroon using 1-D shear wave velocity models obtained from the joint inversion of Rayleigh wave group velocities and P-receiver functions for 32 broad-band seismic stations deployed between 2005 January and 2007 February. We find that (1) crustal thickness (35-39km) and velocity structure is similar beneath the CVL and the Pan African Oubanguides Belt to the south of the CVL, (2) crust is thicker (43-48km) under the northern margin of the Congo Craton and is characterized by shear wave velocities >=4.0kms-1 in its lower part and (3) crust is thinner (26-31km) under the Garoua rift and the coastal plain. In addition, a fast velocity layer (Vs of 3.6-3.8kms-1) in the upper crust is found beneath many of the seismic stations. Crustal structure beneath the CVL and the Oubanguides Belt is very similar to Pan African crustal structure in the Mozambique Belt, and therefore it appears not to have been modified significantly by the magmatic activity associated with the CVL. The crust beneath the coastal plain was probably thinned during the opening of the southern Atlantic Ocean, while the crust beneath the Garoua rift was likely thinned during the formation of the Benue Trough in the early Cretaceous. We suggest that the thickened crust and the thick mafic lower crustal layer beneath the northern margin of the Congo Craton may be relict features from a continent-continent collision along this margin during the formation of Gondwana.

  9. Using velocity dispersion to estimate halo mass: Is the Local Group in tension with ΛCDM?

    Science.gov (United States)

    Elahi, Pascal J.; Power, Chris; Lagos, Claudia del P.; Poulton, Rhys; Robotham, Aaron S. G.

    2018-06-01

    Satellite galaxies are commonly used as tracers to measure the line-of-sight (LOS)velocity dispersion (σLOS) of the dark matter halo associated with their central galaxy, and thereby to estimate the halo's mass. Recent observational dispersion estimates of the Local Group, including the Milky Way and M31, suggest σ ˜50 km s-1, which is surprisingly low when compared to the theoretical expectation of σ ˜100 km s-1 for systems of their mass. Does this pose a problem for Lambda cold dark matter (ΛCDM)? We explore this tension using the SURFS suite of N-body simulations, containing over 10000 (sub)haloes with well tracked orbits. We test how well a central galaxy's host halo velocity dispersion can be recovered by sampling σLOS of subhaloes and surrounding haloes. Our results demonstrate that σLOS is biased mass proxy. We define an optimal window in vLOS and projected distance (Dp) - 0.5 ≲ Dp/Rvir ≲ 1.0 and vLOS ≲ 0.5Vesc, where Rvir is the virial radius and Vesc is the escape velocity - such that the scatter in LOS to halo dispersion is minimized - σLOS = (0.5 ± 0.1)σv, H. We argue that this window should be used to measure LOS dispersions as a proxy for mass, as it minimises scatter in the σLOS-Mvir relation. This bias also naturally explains the results from McConnachie (2012), who used similar cuts when estimating σLOS, LG, producing a bias of σLG = (0.44 ± 0.14)σv, H. We conclude that the Local Group's velocity dispersion does not pose a problem for ΛCDM and has a mass of log M_{LG, vir}/M_{⊙}=12.0^{+0.8}_{-2.0}.

  10. One-velocity neutron diffusion calculations based on a two-group reactor model

    Energy Technology Data Exchange (ETDEWEB)

    Bingulac, S; Radanovic, L; Lazarevic, B; Matausek, M; Pop-Jordanov, J [Boris Kidric Institute of Nuclear Sciences, Vinca, Belgrade (Yugoslavia)

    1965-07-01

    Many processes in reactor physics are described by the energy dependent neutron diffusion equations which for many practical purposes can often be reduced to one-dimensional two-group equations. Though such two-group models are satisfactory from the standpoint of accuracy, they require rather extensive computations which are usually iterative and involve the use of digital computers. In many applications, however, and particularly in dynamic analyses, where the studies are performed on analogue computers, it is preferable to avoid iterative calculations. The usual practice in such situations is to resort to one group models, which allow the solution to be expressed analytically. However, the loss in accuracy is rather great particularly when several media of different properties are involved. This paper describes a procedure by which the solution of the two-group neutron diffusion. equations can be expressed analytically in the form which, from the computational standpoint, is as simple as the one-group model, but retains the accuracy of the two-group treatment. In describing the procedure, the case of a multi-region nuclear reactor of cylindrical geometry is treated, but the method applied and the results obtained are of more general application. Another approach in approximate solution of diffusion equations, suggested by Galanin is applicable only in special ideal cases.

  11. Epidemiological studies of groups with occupational exposure to radiation

    International Nuclear Information System (INIS)

    Davies, J.M.

    1985-01-01

    The exposure of man to radiation and the resulting risk of carcinogenesis continues to be of concern to the public. In this context, there is often a tendency to carry out epidemiological studies concerning the induction of cancer in radiation workers and members of the public which are not supported by a statistically valid data base or whose results are misinterpreted or misused. To assist national authorities in evaluating radiological risks, the Nuclear Energy Agency has sponsored a critical review of the methodologies for, and the limitations of, these epidemiological studies, and of the precautions to be adopted in interpreting their results. Prepared by a consultant, Dr. Joan M. Davies, the review focuses on the problems encountered when carrying out epidemiological studies on groups of workers occupationally exposed to radiations, and using their results for radiological protection purposes. It is published under the responsibility of the Secretary General of the OECD, and does not necessarily reflect the views of Member Governments. The primary objective is to provide background material to be used by national authorities that have responsibilities in the field of radiological protection as well as by other persons interested in this subject

  12. Radiation Therapy Oncology Group clinical trials with misonidazole

    International Nuclear Information System (INIS)

    Wasserman, T.H.; Stetz, J.; Phillips, T.L.

    1981-01-01

    This paper presents a review of the progressive clinical trials of the hypoxic cell radiosensitizer, misonidazole, in the Radiation Therapy Oncology Group (RTOG). Presentation is made of all the schemas of the recently completed and currently active RTOG Phase II and Phase III studies. Detailed information is provided on the clinical toxicity of the Phase II trials, specifically regarding neurotoxicity. With limitations in drug total dose, a variety of dose schedules have proven to be tolerable, with a moderate incidence of nausea and vomiting and mild peripheral neuropathy or central neuropathy. No other organ toxicity has been seen, specifically no liver, renal or bone marrow toxicities. An additional Phase III malignant glioma trial in the Brain Tumor Study Group is described

  13. Three-dimensional P-wave velocity structure derived from local earthquakes at the Katmai group of volcanoes, Alaska

    Science.gov (United States)

    Jolly, A.D.; Moran, S.C.; McNutt, S.R.; Stone, D.B.

    2007-01-01

    The three-dimensional P-wave velocity structure beneath the Katmai group of volcanoes is determined by inversion of more than 10,000 rays from over 1000 earthquakes recorded on a local 18 station short-period network between September 1996 and May 2001. The inversion is well constrained from sea level to about 6??km below sea level and encompasses all of the Katmai volcanoes; Martin, Mageik, Trident, Griggs, Novarupta, Snowy, and Katmai caldera. The inversion reduced the average RMS travel-time error from 0.22??s for locations from the standard one-dimensional model to 0.13??s for the best three-dimensional model. The final model, from the 6th inversion step, reveals a prominent low velocity zone (3.6-5.0??km/s) centered at Katmai Pass and extending from Mageik to Trident volcanoes. The anomaly has values about 20-25% slower than velocities outboard of the region (5.0-6.5??km/s). Moderately low velocities (4.5-6.0??km/s) are observed along the volcanic axis between Martin and Katmai Caldera. Griggs volcano, located about 10??km behind (northwest of) the volcanic axis, has unremarkable velocities (5.0-5.7??km/s) compared to non-volcanic regions. The highest velocities are observed between Snowy and Griggs volcanoes (5.5-6.5??km/s). Relocated hypocenters for the best 3-D model are shifted significantly relative to the standard model with clusters of seismicity at Martin volcano shifting systematically deeper by about 1??km to depths of 0 to 4??km below sea level. Hypocenters for the Katmai Caldera are more tightly clustered, relocating beneath the 1912 scarp walls. The relocated hypocenters allow us to compare spatial frequency-size distributions (b-values) using one-dimensional and three-dimensional models. We find that the distribution of b is significantly changed for Martin volcano, which was characterized by variable values (0.8 < b < 2.0) with standard locations and more uniform values (0.8 < b < 1.2) after relocation. Other seismic clusters at Mageik (1.2 < b

  14. Structure of the Crust Beneath Cameroon, West Africa, from the Joint Inversion of Rayleigh Wave Group Velocities and Receiver Functions

    International Nuclear Information System (INIS)

    Tokam, Alain-Pierre K.; Tabod, Charles T.; Nyblade, Andrew A.; Jordi Julia; Wiens, Douglas A.; Pasyanos, Michael E.

    2009-09-01

    The joint inversion of Rayleigh wave group velocities and receiver functions was carried out to investigate the crustal and uppermost mantle structures beneath Cameroon. This was achieved using data from 32 broadband seismic stations installed for 2 years across Cameroon. The Moho depth estimates reveal that the Precambrian crust is variable across the country and shows some significant differences compared to other similar geologic units in East and South Africa. These differences suggest that the setting of the Cameroon Volcanic Line (CVL) and the eastward extension of the Benue Trough have modified the crust of the Panafrican mobile belt in Cameroon by thinning beneath the Rift area and CVL. The velocity models obtained from the joint inversion show at most stations, a layer with shear wave velocities ≥ 4.0 km/s, indicating the presence of a mafic component in the lower crust, predominant beneath the Congo Craton. The lack of this layer at stations within the Panafrican mobile belt may partly explain the crustal thinning observed beneath the CVL and rift area. The significant presence of this layer beneath the Craton, results from the 2100 Ma magmatic events at the origin of the emplacement of swarms of mafic dykes in the region. The CVL stations are underlain by a crust of 35 km on average except near Mt-Cameroon where it is about 25 km. The crustal thinning observed beneath Mt. Cameroon supported by the observed positive gravity anomalies here, suggests the presence of dense astenospheric material within the lithosphere. Shear wave velocities are found to be slower in the crust and uppermost mantle beneath the CVL than the nearby tectonic terrains, suggesting that the origin of the line may be an entirely mantle process through the edge-flow convection process. (author)

  15. Report of the radiation group on radiation backgrounds and damage in the ISABELLE intersection regions

    International Nuclear Information System (INIS)

    Ludlam, T.; Kistiakowsky, V.; Toohig, T.E.

    1976-01-01

    The Radiation Group was charged to examine radiation aspects of the current ISABELLE design and the projected experimental arrangements. Some samples of questions to be addressed were: (1) how does the overall shielding design impact the experimental design, (2) what backgrounds might be expected from the proposed beam scraping, shaving, etc. schemes, (3) what are the radiation damage considerations for experimental electronics near the beam, and (4) what backgrounds might be expected in an experiment from operation of another experiment in the same or the adjacent intersection region. A review is given based on the ISABELLE Proposal, The Proceedings of the 1975 ISABELLE Summer Study, and the estimate of ISABELLE shielding requirements by Stevens and Thorndike

  16. PERIGEE computer codes for reactor simulation in 3 dimensions, using 1 or 2 neutron velocity groups

    International Nuclear Information System (INIS)

    Olson, A.P.

    1964-02-01

    PERIGEE is a code written in SNAP for the G-20 computer. It solves the one- or two-group neutron diffusion equations by finite-difference methods on a three-dimensional, uniform mesh having a common spacing in the two directions normal to the fuel channels. The positions of mesh points along a fuel channel, relative to points in adjacent channels, may correspond to either NPD or CANDU fuel bundle positions. The extrapolated flux boundary may be specified in sufficient detail to represent a tapered or stepped circumferential reflector, a variable axial length and, for a reactor with axis horizontal, a variable moderator level and a variable plane bottom surface equivalent to the CANDU dump structure. The neutron flux may be normalized to give a specified power output from the hottest fuel bundle or hottest channel, or to give a total thermal power limited by the turbine and generator. Reactor operation may be simulated in finite time steps, taking into account any fuel shifts, any changes in moderator level and the change in nuclear properties of the fuel with increasing irradiation. The appropriate properties are obtained by interpolation from tables supplied for as many as 8 types of fuel bundle. The mean fuel exit burnup can be calculated at equilibrium for a reactor in which the exit burnups for two zones may be adjusted to give radial power flattening and the fuelling schedules may be designed to give axial power flattening in one or both zones. (author)

  17. A CATALOG OF ULTRA-COMPACT HIGH VELOCITY CLOUDS FROM THE ALFALFA SURVEY: LOCAL GROUP GALAXY CANDIDATES?

    International Nuclear Information System (INIS)

    Adams, Elizabeth A. K.; Giovanelli, Riccardo; Haynes, Martha P.

    2013-01-01

    We present a catalog of 59 ultra-compact high velocity clouds (UCHVCs) extracted from the 40% complete ALFALFA HI-line survey. The ALFALFA UCHVCs have median flux densities of 1.34 Jy km s –1 , median angular diameters of 10', and median velocity widths of 23 km s –1 . We show that the full UCHVC population cannot easily be associated with known populations of high velocity clouds. Of the 59 clouds presented here, only 11 are also present in the compact cloud catalog extracted from the commensal GALFA-HI survey, demonstrating the utility of this separate dataset and analysis. Based on their sky distribution and observed properties, we infer that the ALFALFA UCHVCs are consistent with the hypothesis that they may be very low mass galaxies within the Local Volume. In that case, most of their baryons would be in the form of gas, and because of their low stellar content, they remain unidentified by extant optical surveys. At distances of ∼1 Mpc, the UCHVCs have neutral hydrogen (H I) masses of ∼10 5 -10 6 M ☉ , H I diameters of ∼2-3 kpc, and indicative dynamical masses within the H I extent of ∼10 7 -10 8 M ☉ , similar to the Local Group ultra-faint dwarf Leo T. The recent ALFALFA discovery of the star-forming, metal-poor, low mass galaxy Leo P demonstrates that this hypothesis is true in at least one case. In the case of the individual UCHVCs presented here, confirmation of their extragalactic nature will require further work, such as the identification of an optical counterpart to constrain their distance.

  18. A CATALOG OF ULTRA-COMPACT HIGH VELOCITY CLOUDS FROM THE ALFALFA SURVEY: LOCAL GROUP GALAXY CANDIDATES?

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Elizabeth A. K.; Giovanelli, Riccardo; Haynes, Martha P., E-mail: betsey@astro.cornell.edu, E-mail: riccardo@astro.cornell.edu, E-mail: haynes@astro.cornell.edu [Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States)

    2013-05-01

    We present a catalog of 59 ultra-compact high velocity clouds (UCHVCs) extracted from the 40% complete ALFALFA HI-line survey. The ALFALFA UCHVCs have median flux densities of 1.34 Jy km s{sup -1}, median angular diameters of 10', and median velocity widths of 23 km s{sup -1}. We show that the full UCHVC population cannot easily be associated with known populations of high velocity clouds. Of the 59 clouds presented here, only 11 are also present in the compact cloud catalog extracted from the commensal GALFA-HI survey, demonstrating the utility of this separate dataset and analysis. Based on their sky distribution and observed properties, we infer that the ALFALFA UCHVCs are consistent with the hypothesis that they may be very low mass galaxies within the Local Volume. In that case, most of their baryons would be in the form of gas, and because of their low stellar content, they remain unidentified by extant optical surveys. At distances of {approx}1 Mpc, the UCHVCs have neutral hydrogen (H I) masses of {approx}10{sup 5}-10{sup 6} M{sub Sun }, H I diameters of {approx}2-3 kpc, and indicative dynamical masses within the H I extent of {approx}10{sup 7}-10{sup 8} M{sub Sun }, similar to the Local Group ultra-faint dwarf Leo T. The recent ALFALFA discovery of the star-forming, metal-poor, low mass galaxy Leo P demonstrates that this hypothesis is true in at least one case. In the case of the individual UCHVCs presented here, confirmation of their extragalactic nature will require further work, such as the identification of an optical counterpart to constrain their distance.

  19. Acoustic holography for piston sound radiation with non-uniform velocity profiles

    NARCIS (Netherlands)

    Aarts, R.M.; Janssen, A.J.E.M.

    2010-01-01

    The theory of orthogonal (Zernike) expansions of functions on a disk, as used in the diffraction theory of optical aberrations, is applied to obtain (semi-) analytical results for the radiation of sound due to a non-uniformly moving, baffled, circular piston. For this particular case, a scheme for

  20. Velocity-space tomography of fusion plasmas by collective Thomson scattering of gyrotron radiation

    DEFF Research Database (Denmark)

    Salewski, Mirko; Jacobsen, A.S.; Jensen, Thomas

    2016-01-01

    -tonoise ratio becomes fairly low for MeV-range ions. Ions at any energy can be detected well by collective Thomson scattering of mm-wave radiation from a high-power gyrotron. We demonstrate how collective Thomson scattering can be used to measure 푓2퐷푣 in the MeV-range in reactor relevant plasmas...

  1. New Observations of Seismic Group Velocities in the Western Solomon Islands from Cross-Correlation of Ambient Seismic Noise

    Science.gov (United States)

    Ku, C. S.; You, S. H.; Kuo, Y. T.; Huang, B. S.; Wu, Y. M.; Chen, Y. G.; Taylor, F. W.

    2015-12-01

    A MW 8.1 earthquake occurred on 1 April 2007 in the western Solomon Islands. Following this event, a damaging tsunami was induced and hit the Island Gizo where the capital city of Western Province of Solomon Islands located. Several buildings of this city were destroyed and several peoples lost their lives during this earthquake. However, during this earthquake, no near source seismic instrument has been installed in this region. The seismic evaluations for the aftershock sequence, the possible earthquake early warning and tsunami warning were unavailable. For the purpose of knowing more detailed information about seismic activity in this region, we have installed 9 seismic stations (with Trillium 120PA broadband seismometer and Q330S 24bit digitizer) around the rupture zone of the 2007 earthquake since September of 2009. Within a decade, it has been demonstrated both theoretically and experimentally that the Green's function or impulse response between two seismic stations can be retrieved from the cross-correlation of ambient noise. In this study, 6 stations' observations which are more complete during 2011/10 ~ 2012/12 period, were selected for the purpose of the cross-correlation analysis of ambient seismic noise. The group velocities at period 2-20 seconds of 15 station-pairs were extracted by using multiple filter technique (MFT) method. The analyzed results of this study presented significant results of group velocities with higher frequency contents than other studies (20-60 seconds in usually cases) and opened new opportunities to study the shallow crustal structure of the western Solomon Islands.

  2. Pelvic Normal Tissue Contouring Guidelines for Radiation Therapy: A Radiation Therapy Oncology Group Consensus Panel Atlas

    Energy Technology Data Exchange (ETDEWEB)

    Gay, Hiram A., E-mail: hgay@radonc.wustl.edu [Washington University School of Medicine, St Louis, MO (United States); Barthold, H. Joseph [Commonwealth Hematology and Oncology, Weymouth, MA (United States); Beth Israel Deaconess Medical Center, Boston, MA (Israel); O' Meara, Elizabeth [Radiation Therapy Oncology Group, Philadelphia, PA (United States); Bosch, Walter R. [Washington University School of Medicine, St Louis, MO (United States); El Naqa, Issam [Department of Radiation Oncology, McGill University Health Center, Montreal, Quebec (Canada); Al-Lozi, Rawan [Washington University School of Medicine, St Louis, MO (United States); Rosenthal, Seth A. [Radiation Oncology Centers, Radiological Associates of Sacramento, Sacramento, CA (United States); Lawton, Colleen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Lee, W. Robert [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Sandler, Howard [Cedars-Sinai Medical Center, Los Angeles, CA (United States); Zietman, Anthony [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Myerson, Robert [Washington University School of Medicine, St Louis, MO (United States); Dawson, Laura A. [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Willett, Christopher [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Kachnic, Lisa A. [Department of Radiation Oncology, Boston Medical Center, Boston University School of Medicine, Boston, MA (United States); Jhingran, Anuja [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Portelance, Lorraine [University of Miami, Miami, FL (United States); Ryu, Janice [Radiation Oncology Centers, Radiological Associates of Sacramento, Sacramento, CA (United States); and others

    2012-07-01

    Purpose: To define a male and female pelvic normal tissue contouring atlas for Radiation Therapy Oncology Group (RTOG) trials. Methods and Materials: One male pelvis computed tomography (CT) data set and one female pelvis CT data set were shared via the Image-Guided Therapy QA Center. A total of 16 radiation oncologists participated. The following organs at risk were contoured in both CT sets: anus, anorectum, rectum (gastrointestinal and genitourinary definitions), bowel NOS (not otherwise specified), small bowel, large bowel, and proximal femurs. The following were contoured in the male set only: bladder, prostate, seminal vesicles, and penile bulb. The following were contoured in the female set only: uterus, cervix, and ovaries. A computer program used the binomial distribution to generate 95% group consensus contours. These contours and definitions were then reviewed by the group and modified. Results: The panel achieved consensus definitions for pelvic normal tissue contouring in RTOG trials with these standardized names: Rectum, AnoRectum, SmallBowel, Colon, BowelBag, Bladder, UteroCervix, Adnexa{sub R}, Adnexa{sub L}, Prostate, SeminalVesc, PenileBulb, Femur{sub R}, and Femur{sub L}. Two additional normal structures whose purpose is to serve as targets in anal and rectal cancer were defined: AnoRectumSig and Mesorectum. Detailed target volume contouring guidelines and images are discussed. Conclusions: Consensus guidelines for pelvic normal tissue contouring were reached and are available as a CT image atlas on the RTOG Web site. This will allow uniformity in defining normal tissues for clinical trials delivering pelvic radiation and will facilitate future normal tissue complication research.

  3. Reflection of electromagnetic radiation from plasma with an anisotropic electron velocity distribution

    International Nuclear Information System (INIS)

    Vagin, K. Yu.; Uryupin, S. A.

    2013-01-01

    The reflection of a test electromagnetic pulse from the plasma formed as a result of tunnel ionization of atoms in the field of a circularly polarized high-power radiation pulse is analyzed using the kinetic approach to describe electron motion. It is shown that the reflected pulse is significantly amplified due to the development of Weibel instability. The amplification efficiency is determined by the maximum value of the instability growth rate, which depends on the degree of anisotropy of the photoelectron distribution function

  4. Free electron laser and coherent radiation. Working group summary

    International Nuclear Information System (INIS)

    Gover, A.; Csonka, P.; Deacon, D.

    1984-01-01

    The planned development of a new storage ring at SSRL gives hope for the exciting possibility that an x-ray laser may become available in a users facility. Such a device would certainly be a unique and revolutionary tool for scientific research and industrial applications, which may take advantage of the spatial and temporal coherence, high power and high brightness of this device in a wavelength regime where no alternative coherent radiation sources exist. The feasibility of implementing such a device in the new ring should be examined carefully by the ring designers. If conclusions are positive, the ring design should take into account the special requirements which are set by the x-ray laser design parameters. Our working group made the first step in this examination process. Most of the emphasis was put on the consideration of an X-Ray Free Electron Laser (XR FEL). FEL technology has developed in the last few years and was recently demonstrated to operate successfully in the visible wavelength regime in the ACO storage ring in Orsay

  5. Evaporation of Arabian light crude oil spilled on sea and on beach sands : influence of solar radiation and wind velocity

    International Nuclear Information System (INIS)

    Bergueiro, J.R.; Marti, A.; Fuertes, A.; Moreno, S.; Guijarro, S.

    1998-01-01

    The evaporation of crude oil resulting from a spill on sea water was studied to develop a simulation model. Evaporation takes place within a complex process of mass and energy transfer. The effects of physical and chemical variables (such as wind velocity and direct and diffused solar radiation) and the environmental conditions of the spillage were also considered. Arabian crude oil was used in the simulation model for crude oil spillage on sea water. An equation for the evaporation process was used to correlate the evaporated fraction of oil as a function of time. The area of spreading was determined as a function of the dominant stage at each moment of spreading. The evaporation of spilled crude oil on beach sand consisting of three different particle sizes was also studied and used for a simulation model for crude oil spillage on a polluted beach. 7 refs., 6 tabs., 10 figs

  6. Low Energy Gamma Radiation Induced Effects on Ultrasonic Velocity and Acoustic Parameters in Polyvinylidene Fluoride Solution

    Directory of Open Access Journals (Sweden)

    S. S. Kulkarni

    2016-01-01

    Full Text Available The modification of polyvinylidene fluoride (PVDF polymer properties with irradiation is of interest as it possesses unique piezo-, pyro-, and ferroelectric properties. In this paper, we report the results of acoustic parameters of irradiated PVDF mixed with dimethylacetamide (DMAC solution with low energy γ-source (Cs-137. The polymer solution covered with mica film assures only γ-ray passage and the duration was increased from 18 to 50 hours to achieve the higher dose rate. The dose rate was estimated using the strength of the radioactive source and the duration of the exposure. The ultrasonic velocity (v, density (ρ, and viscosity (η of 0.2 wt% and 0.5 wt% PVDF dissolved in pure DMAC solution, irradiated with different dose rate were measured using ultrasonic interferometer (Mittal make, Pyknometer, and Oswald’s viscometer, respectively. It is observed that the values of v, ρ, and η change with dose rate. The acoustic parameters such as adiabatic compressibility (β, intermolecular free path length (Lf, acoustic impedance (Z, relative association (RA, ultrasonic attenuation (α/f2, and relaxation time (τ are calculated using the experimental data. These results are interpreted in terms of the solute-solvent interaction in a polymer solution and scissoring chain damage.

  7. Structure of the Crust beneath Cameroon, West Africa, from the Joint Inversion of Rayleigh Wave Group Velocities and Receiver Functions

    Energy Technology Data Exchange (ETDEWEB)

    Tokam, A K; Tabod, C T; Nyblade, A A; Julia, J; Wiens, D A; Pasyanos, M E

    2010-02-18

    Cameroon using 1-D shear wave velocity models obtained from the joint inversion of Rayleigh wave group velocities and P-receiver functions for 32 broadband seismic stations. From the 1-D shear wave velocity models, we obtain new insights into the composition and structure of the crust and upper mantle across Cameroon. After briefly reviewing the geological framework of Cameroon, we describe the data and the joint inversion method, and then interpret variations in crustal structure found beneath Cameroon in terms of the tectonic history of the region.

  8. Modification of Acute Radiation Response in Different Demographic Age Groups

    Science.gov (United States)

    2017-10-25

    greater radiosensitivity. Other studies provided further mechanistic insight into the observed age effect of radiation responses. For example ...DISTRIBUTION A. Approved for public release; distribution is unlimited. October 2017 HDTRA1-14-0003; 0005 Prepared by: Applied ... Research Associates, Inc. 801 N. Quincy Street Suite 700 Arlington, VA 22203 Modification of Acute Radiation Response in Different Demographic Age

  9. Developing regionalized models of lithospheric thickness and velocity structure across Eurasia and the Middle East from jointly inverting P-wave and S-wave receiver functions with Rayleigh wave group and phase velocities

    Energy Technology Data Exchange (ETDEWEB)

    Julia, J; Nyblade, A; Hansen, S; Rodgers, A; Matzel, E

    2009-07-06

    In this project, we are developing models of lithospheric structure for a wide variety of tectonic regions throughout Eurasia and the Middle East by regionalizing 1D velocity models obtained by jointly inverting P-wave and S-wave receiver functions with Rayleigh wave group and phase velocities. We expect the regionalized velocity models will improve our ability to predict travel-times for local and regional phases, such as Pg, Pn, Sn and Lg, as well as travel-times for body-waves at upper mantle triplication distances in both seismic and aseismic regions of Eurasia and the Middle East. We anticipate the models will help inform and strengthen ongoing and future efforts within the NNSA labs to develop 3D velocity models for Eurasia and the Middle East, and will assist in obtaining model-based predictions where no empirical data are available and for improving locations from sparse networks using kriging. The codes needed to conduct the joint inversion of P-wave receiver functions (PRFs), S-wave receiver functions (SRFs), and dispersion velocities have already been assembled as part of ongoing research on lithospheric structure in Africa. The methodology has been tested with synthetic 'data' and case studies have been investigated with data collected at an open broadband stations in South Africa. PRFs constrain the size and S-P travel-time of seismic discontinuities in the crust and uppermost mantle, SRFs constrain the size and P-S travel-time of the lithosphere-asthenosphere boundary, and dispersion velocities constrain average S-wave velocity within frequency-dependent depth-ranges. Preliminary results show that the combination yields integrated 1D velocity models local to the recording station, where the discontinuities constrained by the receiver functions are superimposed to a background velocity model constrained by the dispersion velocities. In our first year of this project we will (i) generate 1D velocity models for open broadband seismic stations

  10. Evidence for crustal low shear-wave speed in western Saudi Arabia from multi-scale fundamental-mode Rayleigh-wave group-velocity tomography

    KAUST Repository

    Tang, Zheng

    2018-05-15

    We investigate the crustal and upper-mantle shear-velocity structure of Saudi Arabia by fundamental-mode Rayleigh-wave group-velocity tomography and shear-wave velocity inversion. The seismic dataset is compiled using ∼140 stations of the Saudi National Seismic Network (SNSN) operated by the Saudi Geological Survey (SGS). We measure Rayleigh-wave group-velocities at periods of 8–40 s from regional earthquakes. After obtaining 1-D shear-wave velocity models by inverting group-velocities at each grid node, we construct a 3-D shear-velocity model for Saudi Arabia and adjacent regions by interpolating the 1-D models. Our 3-D model indicates significant lateral variations in crustal and lithospheric thickness, as well as in the shear-wave velocity over the study region. In particular, we identify zones of reduced shear-wave speed at crustal levels beneath the Cenozoic volcanic fields in the Arabian Shield. The inferred reductions of 2–5% in shear-wave speed may be interpreted as possibly indicating the presence of partial melts. However, their precise origin we can only speculate about. Our study also reveals an upper-mantle low velocity zone (LVZ) below the Arabian Shield, supporting the model of lateral mantle flow from the Afar plume. Further geophysical experiments are needed to confirm (or refute) the hypothesis that partial melts may exist below the Cenozoic volcanism in western Saudi Arabia, and to build a comprehensive geodynamic–geological model for the evolution and present state of the lithosphere of the Arabian Plate and the Red Sea.

  11. Evidence for crustal low shear-wave speed in western Saudi Arabia from multi-scale fundamental-mode Rayleigh-wave group-velocity tomography

    KAUST Repository

    Tang, Zheng; Mai, Paul Martin; Chang, Sung-Joon; Zahran, Hani

    2018-01-01

    We investigate the crustal and upper-mantle shear-velocity structure of Saudi Arabia by fundamental-mode Rayleigh-wave group-velocity tomography and shear-wave velocity inversion. The seismic dataset is compiled using ∼140 stations of the Saudi National Seismic Network (SNSN) operated by the Saudi Geological Survey (SGS). We measure Rayleigh-wave group-velocities at periods of 8–40 s from regional earthquakes. After obtaining 1-D shear-wave velocity models by inverting group-velocities at each grid node, we construct a 3-D shear-velocity model for Saudi Arabia and adjacent regions by interpolating the 1-D models. Our 3-D model indicates significant lateral variations in crustal and lithospheric thickness, as well as in the shear-wave velocity over the study region. In particular, we identify zones of reduced shear-wave speed at crustal levels beneath the Cenozoic volcanic fields in the Arabian Shield. The inferred reductions of 2–5% in shear-wave speed may be interpreted as possibly indicating the presence of partial melts. However, their precise origin we can only speculate about. Our study also reveals an upper-mantle low velocity zone (LVZ) below the Arabian Shield, supporting the model of lateral mantle flow from the Afar plume. Further geophysical experiments are needed to confirm (or refute) the hypothesis that partial melts may exist below the Cenozoic volcanism in western Saudi Arabia, and to build a comprehensive geodynamic–geological model for the evolution and present state of the lithosphere of the Arabian Plate and the Red Sea.

  12. Renormalization-group approach to nonlinear radiation-transport problems

    International Nuclear Information System (INIS)

    Chapline, G.F.

    1980-01-01

    A Monte Carlo method is derived for solving nonlinear radiation-transport problems that allows one to average over the effects of many photon absorptions and emissions at frequencies where the opacity is large. This method should allow one to treat radiation-transport problems with large optical depths, e.g., line-transport problems, with little increase in computational effort over that which is required for optically thin problems

  13. Air crews - a new group of radiation workers

    International Nuclear Information System (INIS)

    Antic, D.

    1997-01-01

    Air crews on commercial flights are not generally regarded as occupationally exposed radiation workers. The studies show that they may receive radiation doses in excess of the ICRP recommended limits for members of the public. An international approach to this problem could be enforced through IATA and other organizations in commercial air traffic. The results of the analysis for air crews of Yugoslav Airlines are used as example. (author)

  14. Velocities of dislocation groups in very thin neutron-irradiated copper single crystals measured by slip line cinematography

    Energy Technology Data Exchange (ETDEWEB)

    Potthoff, H.H. (Technische Univ. Braunschweig (Germany, F.R.). Inst. fuer Metallphysik und Nukleare Festkoerperphysik)

    1983-05-16

    Slip line development on very thin flat single crystals of neutron-irradiated Cu (thickness down to only 15 to 20 ..mu..m, orientation for single glide, yield region, room temperature) is recorded by high-speed cinematography during tensile deformation. In such very thin crystals glide dislocations on the slip plane must be arranged in a rather simple way. Drops in tensile load occuring during initiation of single slip lines at the Lueders band front indicate that in the beginning of a slip line development dislocation groups traverse the whole glide plane in very short times. Evaluating the data measured for the slip line growth v/sub s/ >= 10 cm/s is found for screw dislocations and v/sub e/ >= v/sub s/ for edge dislocations. For later stages on thin crystals and for all stages on thick crystals (>= several 100 ..mu..m) slip line development is much slower and slip line show many cross slip events which then appear to control the mean velocity of the dislocations.

  15. Velocities of dislocation groups in very thin neutron-irradiated copper single crystals measured by slip line cinematography

    International Nuclear Information System (INIS)

    Potthoff, H.H.

    1983-01-01

    Slip line development on very thin flat single crystals of neutron-irradiated Cu (thickness down to only 15 to 20 μm, orientation for single glide, yield region, room temperature) is recorded by high-speed cinematography during tensile deformation. In such very thin crystals glide dislocations on the slip plane must be arranged in a rather simple way. Drops in tensile load occuring during initiation of single slip lines at the Lueders band front indicate that in the beginning of a slip line development dislocation groups traverse the whole glide plane in very short times. Evaluating the data measured for the slip line growth v/sub s/ >= 10 cm/s is found for screw dislocations and v/sub e/ >= v/sub s/ for edge dislocations. For later stages on thin crystals and for all stages on thick crystals (>= several 100 μm) slip line development is much slower and slip line show many cross slip events which then appear to control the mean velocity of the dislocations. (author)

  16. Commercial airline crews. A new group of occupational radiation workers

    International Nuclear Information System (INIS)

    Brown, D.L.

    1996-01-01

    Aircrews on regular commercial flights are not generally regarded as occupationally exposed radiation workers. Although several studies have indicated that they may receive radiation doses in excess of the ICRP recommended limit for members of the public, the same is true of individuals living at ground level in one of the areas of abnormally high background gamma radiation; and in the past it has been general practice to avoid regarding either of these situations as coming within the radiation dose control practices of the venous regulatory agencies. Furthermore it must be recognized that in areas prone to high background radon levels. even greater unregulated radiation exposures of many individuals take place. ICRP 65 recommends an action level for correcting high radon concentrations in dwellings which comes in the range corresponding to effective doses of between 3 and 10 mSv/y but experience has shown that few homeowners voluntarily carry out remedial work even at these levels. An aircrew member living in a home with abnormally high radon levels may well experience lower effective dose rates whilst in flight than whilst relaxing at home. (author)

  17. Magnetohydrodynamic and thermal radiation effects on the boundary-layer flow due to a moving extensible surface with the velocity slip model: A comparative study of four nanofluids

    Energy Technology Data Exchange (ETDEWEB)

    Aly, Emad H., E-mail: efarag@uj.edu.sa [Department of Mathematics, Faculty of Science, University of Jeddah, Jeddah 21589 (Saudi Arabia); Department of Mathematics, Faculty of Education, Ain Shams University, Roxy, Cairo 11757 (Egypt); Sayed, Hamed M. [Department of Mathematics, Faculty of Education, Ain Shams University, Roxy, Cairo 11757 (Egypt); Department of Mathematics, Faculty of Sciences, Taibah University, Yanbu (Saudi Arabia)

    2017-01-15

    In the current work, we investigated effects of the velocity slip for the flow and heat transfer of four nanofluids over a non-linear stretching sheet taking into account the thermal radiation and magnetic field in presence of the effective electrical conductivity. The governing partial differential equations were transformed into a set of nonlinear ordinary differential equation using similarity transformations before being solved numerically by the Chebyshev pseudospectral differentiation matrix (ChPDM). It was found that the investigated parameters affect remarkably on the nanofluid stream function for the whole investigated nanoparticles. In addition, velocity and skin friction profiles of the four investigated nanofluids decreases and increases, respectively, with the increase of the magnetic parameter, first-order and second-order velocity slips. Further, the flow velocity, surface shear stress and temperature are strongly influenced on applying the velocity slip model, where lower values of the second-order imply higher surface heat flux and thereby making the fluid warmer. - Highlights: • A comparative study for four nanoparticles with MHD and thermal radiation effects was studied. • The effective electrical conductivity is mandatory; otherwise a spurious physical sight will be gained. • The investigated parameters affect remarkably on the nanofluids' flow. • The flow velocity, surface shear stress and temperature are strongly influenced by the slip model. • Lower values of the second-order imply higher surface heat flux and thereby making the fluid warmer.

  18. Radiation protection dosimetry in medicine - Report of the working group n.9 of the European radiation dosimetry group (EURADOS) - coordinated network for radiation dosimetry (CONRAD - contract EC N) fp6-12684; Dosimetrie pour la radioprotection en milieu medical - rapport du groupe de travail n. 9 du European radiation dosimetry group (EURADOS) - coordinated netword for radiation dosimetry (CONRAD - contrat CE fp6-12684)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    This report present the results achieved within the frame of the work the WP 7 (Radiation Protection Dosimetry of Medical Staff) of the coordination action CONRAD (Coordinated Network for Radiation Dosimetry) funded through the 6. EU Framework Program. This action was coordinated by EURADOS (European Radiation Dosimetry Group). EURADOS is an organization founded in 1981 to advance the scientific understanding and the technical development of the dosimetry of ionising radiation in the fields of radiation protection, radiobiology, radiation therapy and medical diagnosis by promoting collaboration between European laboratories. WP7 coordinates and promotes European research for the assessment of occupational exposures to staff in therapeutic and diagnostic radiology workplaces. Research is coordinated through sub-groups covering three specific areas: 1. Extremity dosimetry in nuclear medicine and interventional radiology: this sub-group coordinates investigations in the specific fields of the hospitals and studies of doses to different parts of the hands, arms, legs and feet; 2. Practice of double dosimetry: this sub-group reviews and evaluates the different methods and algorithms for the use of dosemeters placed above and below lead aprons in large exposure during interventional radiology procedures, especially to determine effective doses to cardiologists during cardiac catheterization; and 3. Use of electronic personal dosemeters in interventional radiology: this sub-group coordinates investigations in laboratories and hospitals, and intercomparisons with passive dosemeters with the aim to enable the formulation of standards. (authors)

  19. Working group 6: Health. 2. Biological radiation effects

    International Nuclear Information System (INIS)

    Maisin, J.R.

    1976-01-01

    Health hazards associated with the increasing development of nuclear energy have been evaluated for the Belgian population. Nuclear industry has been shown to be safer than conventional industry, epidemiological and toxicological data connected with the nuclear energy being more complete than those related to the conventional energy. Somatic and genetic effects of small and high doses of ionizing radiations on the Belgian population have been estimated. Small doses of ionizing radiations are expected to promote only carcinogenic effects. The latent period of cancers, the plateau region (period of high risk) and the absolute and relative risk expressed per rem per 10 6 people per year for leukaemia (having the highest risk) and for the ''other cancers'' have been also estimated. These estimations were obtained by linear extrapolation to the 1 rem level from observations made after irradiation at relatively high dose levels and much higher dose rates. Strict protective regulations have been recommended in order to reduce to a minimum the exposure of population to ionizing radiations as well as to get more information on the radioactive genetic and somatic consequences on population. (G.C.)

  20. Radiation protection Group (SC/RP) desperately seeking...

    CERN Document Server

    A. Hervé, Y. Donjoux / SC

    2006-01-01

    We are trying to trace two transit permits (passavants), which constitute the customs clearance documentation for two 'AD6'portable radiation detectors. The two permits (No. 1308 and No. 1309) were sent in the same internal mail envelope towards the middle of March 2006 but never reached their final destination. After weeks of searching in vain, we are now appealing for your help. If you have these two permits in your possession, please get in touch with us. Many thanks in advance. A.HERVE - SC/RP- ( 163168 / 70927) Y.DONJOUX - SC/RP - (160105 / 73171)

  1. Radiation-induced crosslinking of aromatic polymers with cardo group

    International Nuclear Information System (INIS)

    Xu Jun; Zhang Wanxi

    1991-01-01

    The effects of irradiation on the aromatic polymers with cardo group, such as polyetherketone with cardo group (PEK-C) and polyethersulfone with cardo group (PES-C) were studied. It was found that PEK-C and PES-C can be crosslinked by irradiation under vacuum. Moreover, it was also found that the intensity of the shake-up peak of X-ray photoelectron spectroscopy (XPS) for PEK-C and PES-C varies as irradiation dose. Gelation doses (Rg) of PEK-C and PES-C were estimated by shake-up peaks of XPS. (author) 6 refs.; 8 figs.; 3 tabs

  2. Determining the group velocity dispersion by field analysis for the LP0X, LP1X, and LP2X mode groups independently of the fiber length: applications to step-index fibers

    DEFF Research Database (Denmark)

    Israelsen, Stine Møller; Usuga Castaneda, Mario A.; Rottwitt, Karsten

    2017-01-01

    By knowing the electric field distribution of a guided mode in an optical fiber, we are able to evaluate the group velocity dispersion in a weakly guiding step-index fiber for a pure mode in the LP0X, LP1X, and LP2X mode groups independently of the fiber length. We demonstrate the method numerica...

  3. Canadian space agency discipline working group for space dosimetry and radiation science

    International Nuclear Information System (INIS)

    Waker, Anthony; Waller, Edward; Lewis, Brent; Bennett, Leslie; Conroy, Thomas

    2008-01-01

    Full text: One of the great technical challenges in the human and robotic exploration of space is the deleterious effect of radiation on humans and physical systems. The magnitude of this challenge is broadly understood in terms of the sources of radiation, however, a great deal remains to be done in the development of instrumentation, suitable for the space environment, which can provide real-time monitoring of the complex radiation fields encountered in space and a quantitative measure of potential biological risk. In order to meet these research requirements collaboration is needed between experimental nuclear instrumentation scientists, theoretical scientists working on numerical modeling techniques and radiation biologists. Under the auspices of the Canadian Space Agency such a collaborative body has been established as one of a number of Discipline Working Groups. Members of the Space Dosimetry and Radiation Science working group form a collaborative network across Canada including universities, government laboratories and the industrial sector. Three central activities form the core of the Space Dosimetry and Radiation Science DWG. An instrument sub-group is engaged in the development of instruments capable of gamma ray, energetic charged particle and neutron dosimetry including the ability to provide dosimetric information in real-time. A second sub-group is focused on computer modeling of space radiation fields in order to assess the performance of conceptual designs of detectors and dosimeters or the impact of radiation on cellular and sub-cellular biological targets and a third sub-group is engaged in the study of the biological effects of space radiation and the potential of biomarkers as a method of assessing radiation impact on humans. Many working group members are active in more than one sub-group facilitating communication throughout the whole network. A summary progress-report will be given of the activities of the Discipline Working Group and the

  4. Shear wave velocity measurements using acoustic radiation force impulse in young children with normal kidneys versus hydronephrotic kidneys

    Energy Technology Data Exchange (ETDEWEB)

    Shon, Beom Seok; Kim, Myung Joon; Han, Sang Won; Im, Young Jae; Lee, Mi Jung [Severance Children' s Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2014-04-15

    To measure shear wave velocities (SWVs) by acoustic radiation force impulse (ARFI) ultrasound elastography in normal kidneys and in hydronephrotic kidneys in young children and to compare SWVs between the hydronephrosis grades. This study was approved by an institutional review board, and informed consent was obtained from the parents of all the children included. Children under the age of 24 months were prospectively enrolled. Hydronephrosis grade was evaluated on ultrasonography, and three valid ARFI measurements were attempted using a high-frequency transducer for both kidneys. Hydronephrosis was graded from 0 to 4, and high-grade hydronephrosis was defined as grades 3 and 4. Fifty-one children underwent ARFI measurements, and three valid measurements for both kidneys were obtained in 96% (49/51) of the patients. Nineteen children (38.8%) had no hydronephrosis. Twenty-three children (46.9%) had unilateral hydronephrosis, and seven children (14.3%) had bilateral hydronephrosis. Seven children had ureteropelvic junction obstruction (UPJO). Median SWVs in kidneys with high-grade hydronephrosis (2.02 m/sec) were higher than those in normal kidneys (1.75 m/sec; P=0.027). However, the presence of UPJO did not influence the median SWVs in hydronephrotic kidneys (P=0.362). Obtaining ARFI measurements of the kidney is feasible in young children with median SWVs of 1.75 m/sec in normal kidneys. Median SWVs increased in high-grade hydronephrotic kidneys but were not different between hydronephrotic kidneys with and without UPJO.

  5. Shear wave velocity measurements using acoustic radiation force impulse in young children with normal kidneys versus hydronephrotic kidneys

    International Nuclear Information System (INIS)

    Shon, Beom Seok; Kim, Myung Joon; Han, Sang Won; Im, Young Jae; Lee, Mi Jung

    2014-01-01

    To measure shear wave velocities (SWVs) by acoustic radiation force impulse (ARFI) ultrasound elastography in normal kidneys and in hydronephrotic kidneys in young children and to compare SWVs between the hydronephrosis grades. This study was approved by an institutional review board, and informed consent was obtained from the parents of all the children included. Children under the age of 24 months were prospectively enrolled. Hydronephrosis grade was evaluated on ultrasonography, and three valid ARFI measurements were attempted using a high-frequency transducer for both kidneys. Hydronephrosis was graded from 0 to 4, and high-grade hydronephrosis was defined as grades 3 and 4. Fifty-one children underwent ARFI measurements, and three valid measurements for both kidneys were obtained in 96% (49/51) of the patients. Nineteen children (38.8%) had no hydronephrosis. Twenty-three children (46.9%) had unilateral hydronephrosis, and seven children (14.3%) had bilateral hydronephrosis. Seven children had ureteropelvic junction obstruction (UPJO). Median SWVs in kidneys with high-grade hydronephrosis (2.02 m/sec) were higher than those in normal kidneys (1.75 m/sec; P=0.027). However, the presence of UPJO did not influence the median SWVs in hydronephrotic kidneys (P=0.362). Obtaining ARFI measurements of the kidney is feasible in young children with median SWVs of 1.75 m/sec in normal kidneys. Median SWVs increased in high-grade hydronephrotic kidneys but were not different between hydronephrotic kidneys with and without UPJO.

  6. Acoustic radiation force impulse imaging with Virtual Touch™ tissue quantification: mean shear wave velocity of malignant and benign breast masses.

    Science.gov (United States)

    Wojcinski, Sebastian; Brandhorst, Kathrin; Sadigh, Gelareh; Hillemanns, Peter; Degenhardt, Friedrich

    2013-01-01

    Acoustic radiation force impulse imaging (ARFI) with Virtual Touch™ tissue quantification (VTTQ) enables the determination of shear wave velocity (SWV) in meters per second (m/s). The aim of our study was to describe the mean SWV in normal breast tissue and various breast masses. We performed measurements of SWV with ARFI VTTQ in 145 breast masses (57 malignant, 88 benign) and in the adjacent breast parenchyma and adipose tissue. The mean SWV as well as the rate of successful measurements were analyzed. The difference between adipose tissue and parenchyma was statistically significant (3.05 versus 3.65 m/s) (P breast masses, numerous measurements exceeded the upper limit of possible measurement (≥9.10 m/s, indicated as "X.XX m/s"). Nevertheless, the difference between the malignant and benign masses was statistically significant (8.38 ± 1.99 m/s versus 5.39 ± 2.95 m/s) (P < 0.001). The best diagnostic accuracy (75.9%) was achieved when the cutoff point for malignancy was set to 9.10 m/s in ARFI VTTQ. This implies that the SWV was regarded as suspicious when the upper limit of possible measurement was exceeded and the machine returned the value X.XX m/s. In conclusion, ARFI VTTQ is a feasible method for measurement of SWV in a region of interest. Furthermore, we propose the event of a highly elevated SWV as a significant criterion for malignancy. However, the method is technically not yet fully developed, and the problem of unsuccessful measurements must still be solved.

  7. Phase and group velocity tracing analysis of projected wave packet motion along oblique radar beams – qualitative analysis of QP echoes

    Directory of Open Access Journals (Sweden)

    F. S. Kuo

    2007-02-01

    Full Text Available The wave packets of atmospheric gravity waves were numerically generated, with a given characteristic wave period, horizontal wave length and projection mean wind along the horizontal wave vector. Their projection phase and group velocities along the oblique radar beam (vpr and vgr, with different zenith angle θ and azimuth angle φ, were analyzed by the method of phase- and group-velocity tracing. The results were consistent with the theoretical calculations derived by the dispersion relation, reconfirming the accuracy of the method of analysis. The RTI plot of the numerical wave packets were similar to the striation patterns of the QP echoes from the FAI irregularity region. We propose that the striation range rate of the QP echo is equal to the radial phase velocity vpr, and the slope of the energy line across the neighboring striations is equal to the radial group velocity vgr of the wave packet; the horizontal distance between two neighboring striations is equal to the characteristic wave period τ. Then, one can inversely calculate all the properties of the gravity wave responsible for the appearance of the QP echoes. We found that the possibility of some QP echoes being generated by the gravity waves originated from lower altitudes cannot be ruled out.

  8. Joint inversion of teleseismic P waveforms and surface-wave group velocities from ambient seismic noise in the Bohemian Massif

    Czech Academy of Sciences Publication Activity Database

    Růžek, Bohuslav; Plomerová, Jaroslava; Babuška, Vladislav

    2012-01-01

    Roč. 56, č. 1 (2012), s. 107-140 ISSN 0039-3169 R&D Projects: GA ČR GA205/07/1088; GA AV ČR IAA300120709; GA MŠk LM2010008 Institutional research plan: CEZ:AV0Z30120515 Keywords : receiver function * seismic noise * joint inversion * Bohemian Massif * velocity structure Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 0.975, year: 2012

  9. Multiple group radiator and hybrid test heads, possibilities of combining the array technique

    International Nuclear Information System (INIS)

    Wuestenberg, H.

    1993-01-01

    This article is intended to show the important considerations, which led to the development of the multichannel group radiator technique. Trends in development and the advantages and disadvantages of the different possibilities are introduced, against the background of experience now available for these configurative variants of ultrasonic test heads. For this reason, a series of experiences and arguments is reported, from the point of view of the developer of the multi-channel group radiator technique. (orig./HP) [de

  10. Acoustic radiation force impulse imaging with Virtual Touch™ tissue quantification: mean shear wave velocity of malignant and benign breast masses

    Directory of Open Access Journals (Sweden)

    Wojcinski S

    2013-09-01

    Full Text Available Sebastian Wojcinski,1 Kathrin Brandhorst,2 Gelareh Sadigh,3 Peter Hillemanns,1 Friedrich Degenhardt2 1Department of Obstetrics and Gynecology, Hannover Medical School, Hannover, Germany; 2Department of Obstetrics and Gynecology, Franziskus Hospital, Bielefeld, Germany; 3Department of Radiology, Emory University, Atlanta, GA, USA Abstract: Acoustic radiation force impulse imaging (ARFI with Virtual Touch™ tissue quantification (VTTQ enables the determination of shear wave velocity (SWV in meters per second (m/s. The aim of our study was to describe the mean SWV in normal breast tissue and various breast masses. We performed measurements of SWV with ARFI VTTQ in 145 breast masses (57 malignant, 88 benign and in the adjacent breast parenchyma and adipose tissue. The mean SWV as well as the rate of successful measurements were analyzed. The difference between adipose tissue and parenchyma was statistically significant (3.05 versus 3.65 m/s (P < 0.001. Focusing on breast masses, numerous measurements exceeded the upper limit of possible measurement (≥9.10 m/s, indicated as "X.XX m/s". Nevertheless, the difference between the malignant and benign masses was statistically significant (8.38 ± 1.99 m/s versus 5.39 ± 2.95 m/s (P < 0.001. The best diagnostic accuracy (75.9% was achieved when the cutoff point for malignancy was set to 9.10 m/s in ARFI VTTQ. This implies that the SWV was regarded as suspicious when the upper limit of possible measurement was exceeded and the machine returned the value X.XX m/s. In conclusion, ARFI VTTQ is a feasible method for measurement of SWV in a region of interest. Furthermore, we propose the event of a highly elevated SWV as a significant criterion for malignancy. However, the method is technically not yet fully developed, and the problem of unsuccessful measurements must still be solved. Keywords: ARFI VTTQ, elastography, ultrasound, breast imaging

  11. Summary Report of Working Group 5: Beam and Radiation Generation, Monitoring, and Control

    International Nuclear Information System (INIS)

    Church, Mike; Kim, Kiyong

    2010-01-01

    This paper summarizes the activities and presentations of Working Group 5 of the Advanced Accelerator Concepts Workshop held at Annapolis, Maryland in June 2010. Working Group 5 touched on a broad range of topics in the fields of beam and radiation generation and their monitoring and control. These topics were not comprehensively covered in this Workshop, but rather the Working Group concentrated on specific new developments and recent investigations. The Working Group divided its sessions into four broad categories: cathodes and electron guns, radiation generation, beam diagnostics, and beam control and dynamics. This summary is divided into the same structure.

  12. Continuous control of light group velocity from subluminal to superluminal propagation with a standing-wave coupling field in a Rb vapor cell

    International Nuclear Information System (INIS)

    Bae, In-Ho; Moon, Han Seb

    2011-01-01

    We present the continuous control of the light group velocity from subluminal to superluminal propagation with an on-resonant standing-wave coupling field in the 5S 1/2 -5P 1/2 transition of the Λ-type system of 87 Rb atoms. When a coupling field was changed from a traveling-wave to a standing-wave field by adjusting the power of a counterpropagating coupling field, the probe pulse propagation continuously transformed from subluminal propagation, due to electromagnetically induced transparency with the traveling-wave coupling field, to superluminal propagation, due to narrow enhanced absorption with the standing-wave coupling field. The group velocity of the probe pulse was measured to be approximately 0.004c to -0.002c as a function of the disparity between the powers of the copropagating and the counterpropagating coupling fields.

  13. Decomposition of group-velocity-locked-vector-dissipative solitons and formation of the high-order soliton structure by the product of their recombination.

    Science.gov (United States)

    Wang, Xuan; Li, Lei; Geng, Ying; Wang, Hanxiao; Su, Lei; Zhao, Luming

    2018-02-01

    By using a polarization manipulation and projection system, we numerically decomposed the group-velocity-locked-vector-dissipative solitons (GVLVDSs) from a normal dispersion fiber laser and studied the combination of the projections of the phase-modulated components of the GVLVDS through a polarization beam splitter. Pulses with a structure similar to a high-order vector soliton could be obtained, which could be considered as a pseudo-high-order GVLVDS. It is found that, although GVLVDSs are intrinsically different from group-velocity-locked-vector solitons generated in fiber lasers operated in the anomalous dispersion regime, similar characteristics for the generation of pseudo-high-order GVLVDS are obtained. However, pulse chirp plays a significant role on the generation of pseudo-high-order GVLVDS.

  14. Engineering the Frequency Spectrum of Bright Squeezed Vacuum via Group Velocity Dispersion in an SU(1,1) Interferometer

    OpenAIRE

    Lemieux, Samuel; Manceau, Mathieu; Sharapova, Polina R.; Tikhonova, Olga V.; Boyd, Robert W.; Leuchs, Gerd; Chekhova, Maria V.

    2016-01-01

    Bright squeezed vacuum, a promising tool for quantum information, can be generated by high-gain parametric down-conversion. However, its frequency and angular spectra are typically quite broad, which is undesirable for applications requiring single-mode radiation. We tailor the frequency spectrum of high-gain parametric down-conversion using an SU(1,1) interferometer consisting of two nonlinear crystals with a dispersive medium separating them. The dispersive medium allows us to select a narr...

  15. Retrieving robust noise-based seismic velocity changes from sparse data sets: synthetic tests and application to Klyuchevskoy volcanic group (Kamchatka)

    Science.gov (United States)

    Gómez-García, C.; Brenguier, F.; Boué, P.; Shapiro, N. M.; Droznin, D. V.; Droznina, S. Ya; Senyukov, S. L.; Gordeev, E. I.

    2018-05-01

    Continuous noise-based monitoring of seismic velocity changes provides insights into volcanic unrest, earthquake mechanisms and fluid injection in the sub-surface. The standard monitoring approach relies on measuring travel time changes of late coda arrivals between daily and reference noise cross-correlations, usually chosen as stacks of daily cross-correlations. The main assumption of this method is that the shape of the noise correlations does not change over time or, in other terms, that the ambient-noise sources are stationary through time. These conditions are not fulfilled when a strong episodic source of noise, such as a volcanic tremor for example, perturbs the reconstructed Green's function. In this paper we propose a general formulation for retrieving continuous time series of noise-based seismic velocity changes without the requirement of any arbitrary reference cross-correlation function. Instead, we measure the changes between all possible pairs of daily cross-correlations and invert them using different smoothing parameters to obtain the final velocity change curve. We perform synthetic tests in order to establish a general framework for future applications of this technique. In particular, we study the reliability of velocity change measurements versus the stability of noise cross-correlation functions. We apply this approach to a complex dataset of noise cross-correlations at Klyuchevskoy volcanic group (Kamchatka), hampered by loss of data and the presence of highly non-stationary seismic tremors.

  16. Brain Metastasis Velocity: A Novel Prognostic Metric Predictive of Overall Survival and Freedom From Whole-Brain Radiation Therapy After Distant Brain Failure Following Upfront Radiosurgery Alone

    Energy Technology Data Exchange (ETDEWEB)

    Farris, Michael, E-mail: mfarris@wakehealth.edu [Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, North Carolina (United States); McTyre, Emory R.; Cramer, Christina K.; Hughes, Ryan; Randolph, David M.; Ayala-Peacock, Diandra N.; Bourland, J. Daniel [Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, North Carolina (United States); Ruiz, Jimmy [Department of Medicine - Hematology & Oncology, Wake Forest School of Medicine, Winston-Salem, North Carolina (United States); Watabe, Kounosuke [Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, North Carolina (United States); Laxton, Adrian W.; Tatter, Stephen B. [Department of Neurosurgery, Wake Forest School of Medicine, Winston-Salem, North Carolina (United States); Zhou, Xiaobo [Center for Bioinformatics & Systems Biology, Wake Forest School of Medicine, Winston-Salem, North Carolina (United States); Chan, Michael D. [Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, North Carolina (United States)

    2017-05-01

    Purpose: Prior statistical models attempted to identify risk factors for time to distant brain failure (DBF) or time to salvage whole-brain radiation therapy (WBRT) to predict the benefit of early WBRT versus stereotactic radiosurgery (SRS) alone. We introduce a novel clinical metric, brain metastasis velocity (BMV), for predicting clinical outcomes after initial DBF following upfront SRS alone. Methods and Materials: BMV was defined as the cumulative number of new brain metastases that developed over time since first SRS in years. Patients were classified by BMV into low-, intermediate-, and high-risk groups, consisting of <4, 4 to 13, and >13 new metastases per year, respectively. Histology, number of metastases at the time of first SRS, and systemic disease status were assessed for effect on BMV. Results: Of 737 patients treated at our institution with upfront SRS without WBRT, 286 had ≥1 DBF event. A lower BMV predicted for improved overall survival (OS) following initial DBF (log-rank P<.0001). Median OS for the low, intermediate, and high BMV groups was 12.4 months (95% confidence interval [CI], 10.4-16.9 months), 8.2 months (95% CI, 5.0-9.7 months), and 4.3 months (95% CI, 2.6-6.7 months), respectively. Multivariate analysis showed that BMV remained the dominant predictor of OS, with a hazard ratio of 2.75 for the high BMV group (95% CI, 1.94-3.89; P<.0001) and a hazard ratio of 1.65 for the intermediate BMV group (95% CI, 1.18-2.30; P<.004). A lower BMV was associated with decreased rates of salvage WBRT (P=.02) and neurologic death (P=.008). Factors predictive for a higher BMV included ≥2 initial brain metastases (P=.004) and melanoma histology (P=.008). Conclusions: BMV is a novel metric associated with OS, neurologic death, and need for salvage WBRT after initial DBF following upfront SRS alone.

  17. Brain Metastasis Velocity: A Novel Prognostic Metric Predictive of Overall Survival and Freedom From Whole-Brain Radiation Therapy After Distant Brain Failure Following Upfront Radiosurgery Alone

    International Nuclear Information System (INIS)

    Farris, Michael; McTyre, Emory R.; Cramer, Christina K.; Hughes, Ryan; Randolph, David M.; Ayala-Peacock, Diandra N.; Bourland, J. Daniel; Ruiz, Jimmy; Watabe, Kounosuke; Laxton, Adrian W.; Tatter, Stephen B.; Zhou, Xiaobo; Chan, Michael D.

    2017-01-01

    Purpose: Prior statistical models attempted to identify risk factors for time to distant brain failure (DBF) or time to salvage whole-brain radiation therapy (WBRT) to predict the benefit of early WBRT versus stereotactic radiosurgery (SRS) alone. We introduce a novel clinical metric, brain metastasis velocity (BMV), for predicting clinical outcomes after initial DBF following upfront SRS alone. Methods and Materials: BMV was defined as the cumulative number of new brain metastases that developed over time since first SRS in years. Patients were classified by BMV into low-, intermediate-, and high-risk groups, consisting of <4, 4 to 13, and >13 new metastases per year, respectively. Histology, number of metastases at the time of first SRS, and systemic disease status were assessed for effect on BMV. Results: Of 737 patients treated at our institution with upfront SRS without WBRT, 286 had ≥1 DBF event. A lower BMV predicted for improved overall survival (OS) following initial DBF (log-rank P<.0001). Median OS for the low, intermediate, and high BMV groups was 12.4 months (95% confidence interval [CI], 10.4-16.9 months), 8.2 months (95% CI, 5.0-9.7 months), and 4.3 months (95% CI, 2.6-6.7 months), respectively. Multivariate analysis showed that BMV remained the dominant predictor of OS, with a hazard ratio of 2.75 for the high BMV group (95% CI, 1.94-3.89; P<.0001) and a hazard ratio of 1.65 for the intermediate BMV group (95% CI, 1.18-2.30; P<.004). A lower BMV was associated with decreased rates of salvage WBRT (P=.02) and neurologic death (P=.008). Factors predictive for a higher BMV included ≥2 initial brain metastases (P=.004) and melanoma histology (P=.008). Conclusions: BMV is a novel metric associated with OS, neurologic death, and need for salvage WBRT after initial DBF following upfront SRS alone.

  18. Report on the BWR owners group radiation protection/ALARA Committee

    Energy Technology Data Exchange (ETDEWEB)

    Aldrich, L.R. [Commonwealth Edison Co., Downers Grove, IL (United States)

    1995-03-01

    Radiation protection programs at U.S. boiling water reactor (BWR) stations have evolved during the 1980s and early 1990s from a regulatory adherence-based endeavor to a proactive, risk-based radiation protection and prevention mission. The objectives are no longer to merely monitor and document exposure to radiation and radioactive materials. The focus of the current programs is the optimization of radiation protection of occupational workers consistent with the purpose of producing cost-effective electric power. The newly revised 10 CFR 20 defines the term ALARA (as low as reasonably achievable) to take into account the state of technology, the economics of improvements in relation to the state of the technology, and the benefits to the public health and safety. The BWR Owners Group (BWROG) initially formed the Radiation Protection/ALARA Committee in January 1990 to evaluate methods of reducing occupational radiation exposure during refueling outages. Currently, twenty U.S. BWR owner/operators (representing 36 of the operational 37 domestic BWR units), as well as three foreign BWR operators (associate members), have broadened the scope to promote information exchange between BWR radiation protection professionals and develop good practices which will affect optimization of their radiation protection programs. In search of excellence and the challenge of becoming {open_quotes}World Class{close_quotes} performers in radiation protection, the BWROG Radiation Protection/ALARA Committee has recently accepted a role in assisting the member utilities in improving radiation protection performance in a cost-effective manner. This paper will summarize the recent activities of this Committee undertaken to execute their role of exchanging information in pursuit of optimizing the improvement of their collective radiation protection performance.

  19. Report on the BWR owners group radiation protection/ALARA Committee

    International Nuclear Information System (INIS)

    Aldrich, L.R.

    1995-01-01

    Radiation protection programs at U.S. boiling water reactor (BWR) stations have evolved during the 1980s and early 1990s from a regulatory adherence-based endeavor to a proactive, risk-based radiation protection and prevention mission. The objectives are no longer to merely monitor and document exposure to radiation and radioactive materials. The focus of the current programs is the optimization of radiation protection of occupational workers consistent with the purpose of producing cost-effective electric power. The newly revised 10 CFR 20 defines the term ALARA (as low as reasonably achievable) to take into account the state of technology, the economics of improvements in relation to the state of the technology, and the benefits to the public health and safety. The BWR Owners Group (BWROG) initially formed the Radiation Protection/ALARA Committee in January 1990 to evaluate methods of reducing occupational radiation exposure during refueling outages. Currently, twenty U.S. BWR owner/operators (representing 36 of the operational 37 domestic BWR units), as well as three foreign BWR operators (associate members), have broadened the scope to promote information exchange between BWR radiation protection professionals and develop good practices which will affect optimization of their radiation protection programs. In search of excellence and the challenge of becoming open-quotes World Classclose quotes performers in radiation protection, the BWROG Radiation Protection/ALARA Committee has recently accepted a role in assisting the member utilities in improving radiation protection performance in a cost-effective manner. This paper will summarize the recent activities of this Committee undertaken to execute their role of exchanging information in pursuit of optimizing the improvement of their collective radiation protection performance

  20. The selection and use of control groups in epidemiologic studies of radiation and cancer

    International Nuclear Information System (INIS)

    Howe, G.R.; Friedenreich, C.M.; Howe, P.D.

    1990-09-01

    Current risk estimates for radiation-induced cancer are based on epidemiologic studies of humans exposed to high doses of radiation. A critical feature of such studies is the selection of an appropriate control group. This report presents a detailed examination of the principles underlying the selection and use of control groups in such epidemiologic studies. It is concluded that the cohort study is the preferred design, because of the rarity of exposure to high levels of radiation in the general population and because the cohort design is less susceptible to bias. This report also assesses potential bias in current risk estimates for radiation-induced cancer due to inappropriate choice and use of control groups. Detailed summaries are presented for those epidemiologic studies on which the BEIR IV risk estimates are based. It is concluded that confounding is by far the major potential concern. Bias is probably negligible in risk estimates for breast cancer. For lung cancer, risk estimates may be underestimated by about 30 percent for males and 10 percent for females due to confounding of smoking and radiation exposure. For leukemia and cancers of the thyroid and bone, the absence of established non-radiation risk factors with a high prevalence in the population under study suggests that there is unlikely to be any substantial confounding radiation risk estimates. Finally, lifetime excess mortality risks have been estimated for several of the cancers of interest following exposure to radiation based on Canadian age-, sex- and cause-specific mortality rates. It is concluded that errors in measurement exposure, uncertainty in extrapolating the results of high dose studies to low doses and low dose rates, and sampling variation in the epidemiologic studies contribute far more to uncertainty in current risk estimates than do any biases in the epidemiologic studies introduced by inappropriate selection and use of control groups. (161 refs., 19 tabs.)

  1. Modern Radiation Therapy for Extranodal Lymphomas: Field and Dose Guidelines From the International Lymphoma Radiation Oncology Group

    Energy Technology Data Exchange (ETDEWEB)

    Yahalom, Joachim, E-mail: yahalomj@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Illidge, Tim [Institute of Cancer Sciences, University of Manchester, Manchester Academic Health Sciences Centre, The Christie National Health Service Foundation Trust, Manchester (United Kingdom); Specht, Lena [Department of Oncology and Hematology, Rigshospitalet, University of Copenhagen, Copenhagen (Denmark); Hoppe, Richard T. [Department of Radiation Oncology, Stanford University, Palo Alto, California (United States); Li, Ye-Xiong [Department of Radiation Oncology, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Tsang, Richard [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Wirth, Andrew [Division of Radiation Oncology, Peter MacCallum Cancer Institute, St. Andrews Place, East Melbourne (Australia)

    2015-05-01

    Extranodal lymphomas (ENLs) comprise about a third of all non-Hodgkin lymphomas (NHL). Radiation therapy (RT) is frequently used as either primary therapy (particularly for indolent ENL), consolidation after systemic therapy, salvage treatment, or palliation. The wide range of presentations of ENL, involving any organ in the body and the spectrum of histological sub-types, poses a challenge both for routine clinical care and for the conduct of prospective and retrospective studies. This has led to uncertainty and lack of consistency in RT approaches between centers and clinicians. Thus far there is a lack of guidelines for the use of RT in the management of ENL. This report presents an effort by the International Lymphoma Radiation Oncology Group (ILROG) to harmonize and standardize the principles of treatment of ENL, and to address the technical challenges of simulation, volume definition and treatment planning for the most frequently involved organs. Specifically, detailed recommendations for RT volumes are provided. We have applied the same modern principles of involved site radiation therapy as previously developed and published as guidelines for Hodgkin lymphoma and nodal NHL. We have adopted RT volume definitions based on the International Commission on Radiation Units and Measurements (ICRU), as has been widely adopted by the field of radiation oncology for solid tumors. Organ-specific recommendations take into account histological subtype, anatomy, the treatment intent, and other treatment modalities that may be have been used before RT.

  2. Modern Radiation Therapy for Extranodal Lymphomas: Field and Dose Guidelines From the International Lymphoma Radiation Oncology Group

    International Nuclear Information System (INIS)

    Yahalom, Joachim; Illidge, Tim; Specht, Lena; Hoppe, Richard T.; Li, Ye-Xiong; Tsang, Richard; Wirth, Andrew

    2015-01-01

    Extranodal lymphomas (ENLs) comprise about a third of all non-Hodgkin lymphomas (NHL). Radiation therapy (RT) is frequently used as either primary therapy (particularly for indolent ENL), consolidation after systemic therapy, salvage treatment, or palliation. The wide range of presentations of ENL, involving any organ in the body and the spectrum of histological sub-types, poses a challenge both for routine clinical care and for the conduct of prospective and retrospective studies. This has led to uncertainty and lack of consistency in RT approaches between centers and clinicians. Thus far there is a lack of guidelines for the use of RT in the management of ENL. This report presents an effort by the International Lymphoma Radiation Oncology Group (ILROG) to harmonize and standardize the principles of treatment of ENL, and to address the technical challenges of simulation, volume definition and treatment planning for the most frequently involved organs. Specifically, detailed recommendations for RT volumes are provided. We have applied the same modern principles of involved site radiation therapy as previously developed and published as guidelines for Hodgkin lymphoma and nodal NHL. We have adopted RT volume definitions based on the International Commission on Radiation Units and Measurements (ICRU), as has been widely adopted by the field of radiation oncology for solid tumors. Organ-specific recommendations take into account histological subtype, anatomy, the treatment intent, and other treatment modalities that may be have been used before RT

  3. Role of Slip Velocity in a Magneto-Micropolar Fluid Flow from a Radiative Surface with Variable Permeability: A Numerical Study

    Directory of Open Access Journals (Sweden)

    Sharma B.K.

    2017-08-01

    Full Text Available An analysis is presented to describe the hydromagnetic mixed convection flow of an electrically conducting micropolar fluid past a vertical plate through a porous medium with radiation and slip flow regime. A uniform magnetic field has been considered in the study which absorbs the micropolar fluid with a varying suction velocity and acts perpendicular to the porous surface of the above plate. The governing non-linear partial differential equations have been transformed into linear partial differential equations, which are solved numerically by applying the explicit finite difference method. The numerical results are presented graphically in the form of velocity, micro-rotation, concentration and temperature profiles, the skin-friction coefficient, the couple stress coefficient, the rate of heat and mass transfers at the wall for different material parameters.

  4. American Association of Physicists in Medicine Task Group 263: Standardizing Nomenclatures in Radiation Oncology.

    Science.gov (United States)

    Mayo, Charles S; Moran, Jean M; Bosch, Walter; Xiao, Ying; McNutt, Todd; Popple, Richard; Michalski, Jeff; Feng, Mary; Marks, Lawrence B; Fuller, Clifton D; Yorke, Ellen; Palta, Jatinder; Gabriel, Peter E; Molineu, Andrea; Matuszak, Martha M; Covington, Elizabeth; Masi, Kathryn; Richardson, Susan L; Ritter, Timothy; Morgas, Tomasz; Flampouri, Stella; Santanam, Lakshmi; Moore, Joseph A; Purdie, Thomas G; Miller, Robert C; Hurkmans, Coen; Adams, Judy; Jackie Wu, Qing-Rong; Fox, Colleen J; Siochi, Ramon Alfredo; Brown, Norman L; Verbakel, Wilko; Archambault, Yves; Chmura, Steven J; Dekker, Andre L; Eagle, Don G; Fitzgerald, Thomas J; Hong, Theodore; Kapoor, Rishabh; Lansing, Beth; Jolly, Shruti; Napolitano, Mary E; Percy, James; Rose, Mark S; Siddiqui, Salim; Schadt, Christof; Simon, William E; Straube, William L; St James, Sara T; Ulin, Kenneth; Yom, Sue S; Yock, Torunn I

    2018-03-15

    A substantial barrier to the single- and multi-institutional aggregation of data to supporting clinical trials, practice quality improvement efforts, and development of big data analytics resource systems is the lack of standardized nomenclatures for expressing dosimetric data. To address this issue, the American Association of Physicists in Medicine (AAPM) Task Group 263 was charged with providing nomenclature guidelines and values in radiation oncology for use in clinical trials, data-pooling initiatives, population-based studies, and routine clinical care by standardizing: (1) structure names across image processing and treatment planning system platforms; (2) nomenclature for dosimetric data (eg, dose-volume histogram [DVH]-based metrics); (3) templates for clinical trial groups and users of an initial subset of software platforms to facilitate adoption of the standards; (4) formalism for nomenclature schema, which can accommodate the addition of other structures defined in the future. A multisociety, multidisciplinary, multinational group of 57 members representing stake holders ranging from large academic centers to community clinics and vendors was assembled, including physicists, physicians, dosimetrists, and vendors. The stakeholder groups represented in the membership included the AAPM, American Society for Radiation Oncology (ASTRO), NRG Oncology, European Society for Radiation Oncology (ESTRO), Radiation Therapy Oncology Group (RTOG), Children's Oncology Group (COG), Integrating Healthcare Enterprise in Radiation Oncology (IHE-RO), and Digital Imaging and Communications in Medicine working group (DICOM WG); A nomenclature system for target and organ at risk volumes and DVH nomenclature was developed and piloted to demonstrate viability across a range of clinics and within the framework of clinical trials. The final report was approved by AAPM in October 2017. The approval process included review by 8 AAPM committees, with additional review by ASTRO

  5. Radiation protection dosimetry in medicine - Report of the working group n.9 of the European radiation dosimetry group (EURADOS) - coordinated network for radiation dosimetry (CONRAD - contract EC N) fp6-12684

    International Nuclear Information System (INIS)

    2009-01-01

    This report present the results achieved within the frame of the work the WP 7 (Radiation Protection Dosimetry of Medical Staff) of the coordination action CONRAD (Coordinated Network for Radiation Dosimetry) funded through the 6. EU Framework Program. This action was coordinated by EURADOS (European Radiation Dosimetry Group). EURADOS is an organization founded in 1981 to advance the scientific understanding and the technical development of the dosimetry of ionising radiation in the fields of radiation protection, radiobiology, radiation therapy and medical diagnosis by promoting collaboration between European laboratories. WP7 coordinates and promotes European research for the assessment of occupational exposures to staff in therapeutic and diagnostic radiology workplaces. Research is coordinated through sub-groups covering three specific areas: 1. Extremity dosimetry in nuclear medicine and interventional radiology: this sub-group coordinates investigations in the specific fields of the hospitals and studies of doses to different parts of the hands, arms, legs and feet; 2. Practice of double dosimetry: this sub-group reviews and evaluates the different methods and algorithms for the use of dosemeters placed above and below lead aprons in large exposure during interventional radiology procedures, especially to determine effective doses to cardiologists during cardiac catheterization; and 3. Use of electronic personal dosemeters in interventional radiology: this sub-group coordinates investigations in laboratories and hospitals, and intercomparisons with passive dosemeters with the aim to enable the formulation of standards. (authors)

  6. Radiation Therapy for Primary Cutaneous Anaplastic Large Cell Lymphoma: An International Lymphoma Radiation Oncology Group Multi-institutional Experience

    Energy Technology Data Exchange (ETDEWEB)

    Million, Lynn, E-mail: lmillion@stanford.edu [Stanford Cancer Institute, Stanford, California (United States); Yi, Esther J.; Wu, Frank; Von Eyben, Rie [Stanford Cancer Institute, Stanford, California (United States); Campbell, Belinda A. [Department of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, East Melbourne (Australia); Dabaja, Bouthaina [The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Tsang, Richard W. [Department of Radiation Oncology, Princess Margaret Cancer Centre, Toronto, Ontario (Canada); Ng, Andrea [Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Wilson, Lynn D. [Department of Therapeutic Radiology/Radiation Oncology, Yale School of Medicine, Yale Cancer Center, New Haven, Connecticut (United States); Ricardi, Umberto [Department of Oncology, University of Turin, Turin (Italy); Kirova, Youlia [Institut Curie, Paris (France); Hoppe, Richard T. [Stanford Cancer Institute, Stanford, California (United States)

    2016-08-01

    Purpose: To collect response rates of primary cutaneous anaplastic large cell lymphoma, a rare cutaneous T-cell lymphoma, to radiation therapy (RT), and to determine potential prognostic factors predictive of outcome. Methods and Materials: The study was a retrospective analysis of patients with primary cutaneous anaplastic large cell lymphoma who received RT as primary therapy or after surgical excision. Data collected include initial stage of disease, RT modality (electron/photon), total dose, fractionation, response to treatment, and local recurrence. Radiation therapy was delivered at 8 participating International Lymphoma Radiation Oncology Group institutions worldwide. Results: Fifty-six patients met the eligibility criteria, and 63 tumors were treated: head and neck (27%), trunk (14%), upper extremities (27%), and lower extremities (32%). Median tumor size was 2.25 cm (range, 0.6-12 cm). T classification included T1, 40 patients (71%); T2, 12 patients (21%); and T3, 4 patients (7%). The median radiation dose was 35 Gy (range, 6-45 Gy). Complete clinical response (CCR) was achieved in 60 of 63 tumors (95%) and partial response in 3 tumors (5%). After CCR, 1 tumor recurred locally (1.7%) after 36 Gy and 7 months after RT. This was the only patient to die of disease. Conclusions: Primary cutaneous anaplastic large cell lymphoma is a rare, indolent cutaneous lymphoma with a low death rate. This analysis, which was restricted to patients selected for treatment with radiation, indicates that achieving CCR was independent of radiation dose. Because there were too few failures (<2%) for statistical analysis on dose response, 30 Gy seems to be adequate for local control, and even lower doses may suffice.

  7. Advisory group meeting on new trends and developments in radiation technology

    International Nuclear Information System (INIS)

    1993-02-01

    High energy, ionizing radiation (gamma and electron beams) has been used by industry for many years and for different applications. Well established applications include: industrial sterilization of health care products (medical products and medicinals), radiation modification of plastics (crosslinking of wire and cable insulation, heat shrinkable materials, etc.) and radiation curing of adhesives and coatings on different substrates. The main purpose of the Advisory Group Meeting was to provide a forum for an exchange of information about the new developments in radiation technology, to review the status of these developments and to discuss potential for commercial applications. A further objective was to discuss the role of the International Atomic Energy Agency in promoting new technologies, research and transfer of technology to developing countries. The meeting was expected to prepare recommendations to the Agency for future activities and programmes in this field. Refs, figs and tabs

  8. Modern Radiation Therapy for Hodgkin Lymphoma: Field and Dose Guidelines From the International Lymphoma Radiation Oncology Group (ILROG)

    International Nuclear Information System (INIS)

    Specht, Lena; Yahalom, Joachim; Illidge, Tim; Berthelsen, Anne Kiil; Constine, Louis S.; Eich, Hans Theodor; Girinsky, Theodore; Hoppe, Richard T.; Mauch, Peter; Mikhaeel, N. George; Ng, Andrea

    2014-01-01

    use of ISRT has not yet been validated in a formal study, it is more conservative than INRT, accounting for suboptimal information and appropriately designed for safe local disease control. The goal of modern smaller field radiation therapy is to reduce both treatment volume and treatment dose while maintaining efficacy and minimizing acute and late sequelae. This review is a consensus of the International Lymphoma Radiation Oncology Group (ILROG) Steering Committee regarding the modern approach to RT in the treatment of HL, outlining a new concept of ISRT in which reduced treatment volumes are planned for the effective control of involved sites of HL. Nodal and extranodal non-Hodgkin lymphomas (NHL) are covered separately by ILROG guidelines

  9. Medical Management of the Acute Radiation Syndrome: Recommendations of the Strategic National Stockpile Radiation Working Group

    Science.gov (United States)

    2004-06-15

    STATEMENT Approved for public release; distribution unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT 15. SUBJECT TERMS 16. SECURITY ...Assistance Medicine http://usuhs.mil U.S. Army www.nbc-med.org U.S. Department of Homeland Security Working Group on Radiological Dispersal Device...22. 97. Abbott B, Ippoliti C, Bruton J, Neumann J, Whaley R, Champlin R. Antiemetic efficacy of granisetron plus dexamethasone in bone marrow

  10. Medical Managment of the Acute Radiation Syndrome: Recommendations of the Strategic National Stockpile Radiation Working Group

    Science.gov (United States)

    2004-06-15

    AVAILABILITY STATEMENT Approved for public release; distribution unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT 15. SUBJECT TERMS 16. SECURITY ...Humanitarian Assistance Medicine http://usuhs.mil U.S. Army www.nbc-med.org U.S. Department of Homeland Security Working Group on Radiological Dispersal...2002:11-22. 97. Abbott B, Ippoliti C, Bruton J, Neumann J, Whaley R, Champlin R. Antiemetic efficacy of granisetron plus dexamethasone in bone marrow

  11. MHD free convection flow of a visco-elastic (Kuvshiniski type dusty gas through a semi infinite plate moving with velocity decreasing exponentially with time and radiative heat transfer

    Directory of Open Access Journals (Sweden)

    Om Prakash

    2011-06-01

    Full Text Available The present paper is concerned with the study of MHD free convective flow of a visco-elastic (Kuvshinski type dusty gas through a porous medium induced by the motion of a semi-infinite flat plate under the influence of radiative heat transfer moving with velocity decreasing exponentially with time. The expressions for velocity distribution of a dusty gas and dust particles, concentration profile and temperature field are obtained. The effect of Schmidt number (Sc, Magnetic field parameter (M and Radiation parameter (N on velocity distribution of dusty gas and dust particles, concentration and temperature distribution are discussed graphically.

  12. Intraoperative radiation therapy using mobile electron linear accelerators: Report of AAPM Radiation Therapy Committee Task Group No. 72

    International Nuclear Information System (INIS)

    Sam Beddar, A.; Biggs, Peter J.; Chang Sha; Ezzell, Gary A.; Faddegon, Bruce A.; Hensley, Frank W.; Mills, Michael D.

    2006-01-01

    Intraoperative radiation therapy (IORT) has been customarily performed either in a shielded operating suite located in the operating room (OR) or in a shielded treatment room located within the Department of Radiation Oncology. In both cases, this cancer treatment modality uses stationary linear accelerators. With the development of new technology, mobile linear accelerators have recently become available for IORT. Mobility offers flexibility in treatment location and is leading to a renewed interest in IORT. These mobile accelerator units, which can be transported any day of use to almost any location within a hospital setting, are assembled in a nondedicated environment and used to deliver IORT. Numerous aspects of the design of these new units differ from that of conventional linear accelerators. The scope of this Task Group (TG-72) will focus on items that particularly apply to mobile IORT electron systems. More specifically, the charges to this Task Group are to (i) identify the key differences between stationary and mobile electron linear accelerators used for IORT (ii) describe and recommend the implementation of an IORT program within the OR environment, (iii) present and discuss radiation protection issues and consequences of working within a nondedicated radiotherapy environment, (iv) describe and recommend the acceptance and machine commissioning of items that are specific to mobile electron linear accelerators, and (v) design and recommend an efficient quality assurance program for mobile systems

  13. Formation of potential radiation risk groups to render timely targeted medical care: Lessons of Chernobyl

    International Nuclear Information System (INIS)

    Ivanov, V. K.; Kashcheev, V. V.; Zamulaeva, I. A.; Saenko, A. S.; Orlova, N. V.; Smirnova, S. G.; Korelo, A. M.; Gorsky, A. I.; Maksioutov, M. A.

    2012-01-01

    The paper discusses technology for establishing potential cancer risk groups, based on methods of molecular and radiation epidemiology. Assay of gene mutations at the T-cell receptor (TCR) locus as the method of molecular epidemiology was used for measuring the frequency of TCR-mutations in 320 nuclear workers of the Inst. of Physics and Power Engineering (IPPE). The method of radiation epidemiology was applied to the estimation of attributable risk fraction (ARF) for solid cancers in these groups. The main estimates of radiation risk after the Chernobyl accident are in close agreement with the International Commission on Radiological Protection (ICRP) Publication, 103 models published in 2007. In nuclear workers of the IPPE with ARF ≥ 10%, the increased level of TCR-mutations occurs more often (risk ratio=9.7; 95% CI: 2.9; 32.1). (authors)

  14. Production of urethane group containing coatings by curing with ionizing radiation

    International Nuclear Information System (INIS)

    Spoor, H.; Demmler, K.

    1975-01-01

    A process is described for the manufacture of coatings by applying ionizing radiation to a composition which contains olefinically unsaturated polymeric materials having urethane groups and which has been applied to a substrate. The polymeric materials may be used in combination with olefinically unsaturated monomeric compounds and conventional additives. (U.S.)

  15. An organic group contribution approach to radiative efficiency estimation of organic working fluid

    International Nuclear Information System (INIS)

    Zhang, Xinxin; Kobayashi, Noriyuki; He, Maogang; Wang, Jingfu

    2016-01-01

    Highlights: • We use group contribution method to estimate radiative efficiency. • CFC, HCFC, HFC, HFE, and PFC were estimated using this method. • In most cases, the estimation value has a good precision. • The method is reliable for the estimation of molecule with a symmetric structure. • This estimation method can offer good reference for working fluid development. - Abstract: The ratification of the Montreal Protocol in 1987 and the Kyoto Protocol in 1997 mark an environment protection era of the development of organic working fluid. Ozone depletion potential (ODP) and global warming potential (GWP) are two most important indices for the quantitative comparison of organic working fluid. Nowadays, more and more attention has been paid to GWP. The calculation of GWP is an extremely complicated process which involves interactions between surface and atmosphere such as atmospheric radiative transfer and atmospheric chemical reactions. GWP of a substance is related to its atmospheric abundance and is a variable in itself. However, radiative efficiency is an intermediate parameter for GWP calculation and it is a constant value used to describe inherent property of a substance. In this paper, the group contribution method was adopted to estimate the radiative efficiency of the organic substance which contains more than one carbon atom. In most cases, the estimation value and the standard value are in a good agreement. The biggest estimation error occurs in the estimation of the radiative efficiency of fluorinated ethers due to its plenty of structure groups and its complicated structure compared with hydrocarbon. This estimation method can be used to predict the radiative efficiency of newly developed organic working fluids.

  16. Radiation effects analysis in a group of interventional radiologists using biological and physical dosimetry methods

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, M., E-mail: WEMLmirapas@iqn.upv.e [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera s/n, 46022 Valencia (Spain); Montoro, A.; Almonacid, M. [Radiation Protection Service, Hospital Universitario La Fe Valencia (Spain); Ferrer, S. [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera s/n, 46022 Valencia (Spain); Barquinero, J.F. [Biological Dosimetry Service, Unit of Anthropology, Department of Animal and Vegetable Biology and Ecology, Universitat Autonoma de Barcelona (UAB) (Spain); Tortosa, R. [Radiation Protection Service, Hospital Universitario La Fe Valencia (Spain); Verdu, G. [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera s/n, 46022 Valencia (Spain); Rodriguez, P. [Biological Dosimetry Service, Unit of Anthropology, Department of Animal and Vegetable Biology and Ecology, Universitat Autonoma de Barcelona (UAB) (Spain); Barrios, L.L. [Department of Physiology and Cellular Biology, Unit of Cellular Biology (UAB) (Spain); Villaescusa, J.I. [Radiation Protection Service, Hospital Universitario La Fe Valencia (Spain)

    2010-08-15

    Interventional radiologists and staff members are frequently exposed to protracted and fractionated low doses of ionizing radiation, which extend during all their professional activities. These exposures can derive, due to the effects of direct and scattered radiation, in deterministic effects (radiodermitis, aged skin, cataracts, telangiectasia in nasal region, vasocellular epitelioms, hands depilation) and/or stochastic ones (cancer incidence). A methodology has been proposed for estimating the radiation risk or detriment from a group of six exposed interventional radiologists of the Hospital Universitario La Fe (Valencia, Spain), which had developed general exposition symptoms attributable to deterministic effects of ionizing radiation. Equivalent doses have been periodically registered using TLD's and wrist dosimeters, H{sub p}(10) and H{sub p}(0.07), respectively, and estimated through the observation of translocations in lymphocytes of peripheral blood (biological methods), by extrapolating the yield of translocations to their respective dose-effect curves. The software RADRISK has been applied for estimating radiation risks in these occupational radiation exposures. This software is based on transport models from epidemiological studies of population exposed to external sources of ionizing radiation, such as Hiroshima and Nagasaki atomic bomb survivors [UNSCEAR, Sources and effects of ionizing radiation: 2006 report to the general assembly, with scientific annexes. New York: United Nations; 2006]. The minimum and maximum average excess ratio for skin cancer has been, using wrist physical doses, of [1.03x10{sup -3}, 5.06x10{sup -2}], concluding that there is not an increased risk of skin cancer incidence. The minimum and maximum average excess ratio for leukemia has been, using TLD physical doses, of [7.84x10{sup -2}, 3.36x10{sup -1}], and using biological doses, of [1.40x10{sup -1}, 1.51], which is considerably higher than incidence rates, showing an

  17. The level of sulphydryl groups as an indicator of radiation treatment of meat

    International Nuclear Information System (INIS)

    Stockhausen, K.; Boegl, W.

    1978-01-01

    A biochemical procedure for the identification of irradiated pork meat (fillet, liver and heart) for doses ranging between 0.1 and 2.5 Mrad is described. Spectrophotometric determination of the sulphydryl content in irradiated and unirradiated (control) animal tissue using 6,6'-dithiodinicotinic acid (DTDNA) is applied. Ionizing radiation causes a permanent loss of sulphydryl groups in animal tissue such as meat. The dose-effect relations for this radiation-induced decrease in sulphydryl content does not follow a single function. It may be correlated with a double-exponential function, indicating that the sulphydryl content consists of two classes of widely different radiosensitivity. The most radiosensitive fraction represents approximately 20-50% of the total sulphydryl content. The G-values for the radiation-induced oxidation of sulphydryl groups in this fraction are close to 23 molecules per 100eV radiation energy absorbed by the animal tissue. For the fraction of the lower radiosensitivity the G-values reach 3-7 molecules per 100eV. Irradiation conditions, preparations of protein suspensions from meat, spectrophotometric investigations and other experimental details are reported. The results presented demonstrate that spectrophotometric determination of sulphydryl groups in irradiated meat is a promising specific and comparatively simple method of irradiation control in the dose range between a few krad and several Mrad. (author)

  18. BANYAN. III. Radial velocity, rotation, and X-ray emission of low-mass star candidates in nearby young kinematic groups

    Energy Technology Data Exchange (ETDEWEB)

    Malo, Lison; Artigau, Étienne; Doyon, René; Lafrenière, David; Albert, Loïc; Gagné, Jonathan, E-mail: malo@astro.umontreal.ca, E-mail: doyon@astro.umontreal.ca [Département de physique and Observatoire du Mont-Mégantic, Université de Montréal, Montréal, QC H3C 3J7 (Canada)

    2014-06-10

    Based on high-resolution spectra obtained with PHOENIX at Gemini-South, CRIRES at VLT-UT1, and ESPaDOnS at the Canada-France-Hawaii Telescope, we present new measurements of the radial and projected rotational velocities of 219 low-mass stars. The target likely membership was initially established using the Bayesian analysis tool recently presented in Malo et al., taking into account only the position, proper motion, and photometry of the stars to assess their membership probability. In the present study, we include radial velocity as an additional input to our analysis, and in doing so we confirm the high membership probability for 130 candidates: 27 in β Pictoris, 22 in Tucana-Horologium, 25 in Columba, 7 in Carina, 18 in Argus and 18 in AB Doradus, and 13 with an ambiguous membership. Our analysis also confirms the membership of 57 stars proposed in the literature. A subsample of 16 candidates was observed at 3 or more epochs, allowing us to discover 6 new spectroscopic binaries. The fraction of binaries in our sample is 25%, consistent with values in the literature. Of the stars in our sample, 20% show projected rotational velocities (vsin i) higher than 30 km s{sup –1} and therefore are considered as fast rotators. A parallax and other youth indicators are still needed to fully confirm the 130 highly probable candidates identified here as new bona fide members. Finally, based on the X-ray emission of bona fide and highly probable group members, we show that for low-mass stars in the 12-120 Myr age range, the X-ray luminosity is an excellent indicator of youth and better than the more traditionally used R {sub X} parameter, the ratio of X-ray to bolometric luminosity.

  19. Integration of social aspects in radiation protection. The AIRP Work group on communication

    International Nuclear Information System (INIS)

    Cantone, Marie C.; Magnoni, Mauro; Sturloni, Giancarlo

    2008-01-01

    Radiation protection has never been confined just to its scientific and quantitative aspects as it also incorporates a real and proper social factor. In most developed countries, considerations on the social and ethical issues of radiation protection and discussions on the approaches to stakeholder involvement are in a state of positive turmoil. Scientific and practical experts are identifying and promoting dialogue procedures, embracing ethical and social aspects, and are moving together to add to their experience in new and improved practices for the decision-making process. In early 2006, the Italian Radiation Protection Association (AIRP) set up a workgroup for the purpose of: 1-) Promoting dialogue among RP experts, experts in other disciplines, national and local authorities and the public, in relation to social awareness issues in the fields of ionising and non-ionising radiation protection; 2-) Promoting reflection on the mutual interactions between radiation protection and society; 3-) Contributing to the development and diffusion in the RP community of the culture of stakeholder engagement in the decision-making process. Aiming at promoting continual dialogue between the radiation protection community and society, an initial meeting was held in June 2006 on the fundamentals and objectives of RP communication, by focusing on issues such as: the credibility of information sources, the role of the mass media and institutions in risk communication. A workshop was held in November 2006 on the social aspects of radiation protection: experts in scientific journalism, sociology and medical physics, representatives of consumer associations, participants in a Government task commission, local authorities and representatives of the leading local and national institutions involved in RP, were given the opportunity of communicating and discussing the main socially-sensitive aspects of RP. The work of the AIRP group continued in 2007 with two events related on the

  20. Multi-Group Reductions of LTE Air Plasma Radiative Transfer in Cylindrical Geometries

    Science.gov (United States)

    Scoggins, James; Magin, Thierry Edouard Bertran; Wray, Alan; Mansour, Nagi N.

    2013-01-01

    Air plasma radiation in Local Thermodynamic Equilibrium (LTE) within cylindrical geometries is studied with an application towards modeling the radiative transfer inside arc-constrictors, a central component of constricted-arc arc jets. A detailed database of spectral absorption coefficients for LTE air is formulated using the NEQAIR code developed at NASA Ames Research Center. The database stores calculated absorption coefficients for 1,051,755 wavelengths between 0.04 µm and 200 µm over a wide temperature (500K to 15 000K) and pressure (0.1 atm to 10.0 atm) range. The multi-group method for spectral reduction is studied by generating a range of reductions including pure binning and banding reductions from the detailed absorption coefficient database. The accuracy of each reduction is compared to line-by-line calculations for cylindrical temperature profiles resembling typical profiles found in arc-constrictors. It is found that a reduction of only 1000 groups is sufficient to accurately model the LTE air radiation over a large temperature and pressure range. In addition to the reduction comparison, the cylindrical-slab formulation is compared with the finite-volume method for the numerical integration of the radiative flux inside cylinders with varying length. It is determined that cylindrical-slabs can be used to accurately model most arc-constrictors due to their high length to radius ratios.

  1. Existence and switching behavior of bright and dark Kerr solitons in whispering-gallery mode resonators with zero group-velocity dispersion

    Science.gov (United States)

    Talla Mbé, Jimmi H.; Milián, Carles; Chembo, Yanne K.

    2017-07-01

    We use the generalized Lugiato-Lefever model to investigate the phenomenon of Kerr optical frequency comb generation when group-velocity dispersion is null. In that case, the first dispersion term that plays a leading role is third-order dispersion. We show that this term is sufficient to allow for the existence of both bright and dark solitons. We identify the areas in the parameter space where both kind of solitons can be excited inside the resonator. We also unveil a phenomenon of hysteretic switching between these two types of solitons when the power of the pump laser is cyclically varied. Contribution to the Topical Issue "Theory and Applications of the Lugiato-Lefever Equation", edited by Yanne K. Chembo, Damia Gomila, Mustapha Tlidi, Curtis R. Menyuk.

  2. High-order-harmonic generation from solids: The contributions of the Bloch wave packets moving at the group and phase velocities

    Science.gov (United States)

    Du, Tao-Yuan; Huang, Xiao-Huan; Bian, Xue-Bin

    2018-01-01

    We study numerically the Bloch electron wave-packet dynamics in periodic potentials to simulate laser-solid interactions. We introduce an alternative perspective in the coordinate space combined with the motion of the Bloch electron wave packets moving at group and phase velocities under the laser fields. This model interprets the origins of the two contributions (intra- and interband transitions) in the high-order harmonic generation (HHG) processes by investigating the local and global behaviours of the wave packets. It also elucidates the underlying physical picture of the HHG intensity enhancement by means of carrier-envelope phase, chirp, and inhomogeneous fields. It provides a deep insight into the emission of high-order harmonics from solids. This model is instructive for experimental measurements and provides an alternative avenue to distinguish mechanisms of the HHG from solids in different laser fields.

  3. Slowdown of group velocity of light in dual-frequency laser-pumped cascade structure of Er3+-doped optical fiber at room temperature

    Science.gov (United States)

    Qiu, Wei; Yang, Yujing; Gao, Yuan; Liu, Jianjun; Lv, Pin; Jiang, Qiuli

    2018-04-01

    Slow light is demonstrated in the cascade structure of an erbium-doped fiber with two forward propagation pumps. The results of the numerical simulation of the time delay and the optimum modulation frequency complement each other. The time delay and the optimum modulation frequency depend on the pump ratio G (G  =  {{P}1480}:{{P}980} ). The discussion results of this paper show that a larger time delay of slow light propagation can be obtained in the cascade structure of Er3+-doped optical fibers with dual-frequency laser pumping. Compared to previous research methods, the dual-frequency laser-pumped cascade structure of an Er3+-doped optical fiber is more controllable. Based on our discussion the pump ratio G should be selected in order to obtain a more appropriate time delay and the slowdown of group velocity.

  4. An HST/COS legacy survey of high-velocity ultraviolet absorption in the Milky Way's circumgalactic medium and the Local Group

    Science.gov (United States)

    Richter, P.; Nuza, S. E.; Fox, A. J.; Wakker, B. P.; Lehner, N.; Ben Bekhti, N.; Fechner, C.; Wendt, M.; Howk, J. C.; Muzahid, S.; Ganguly, R.; Charlton, J. C.

    2017-11-01

    Context. The Milky Way is surrounded by large amounts of diffuse gaseous matter that connects the stellar body of our Galaxy with its large-scale Local Group (LG) environment. Aims: To characterize the absorption properties of this circumgalactic medium (CGM) and its relation to the LG we present the so-far largest survey of metal absorption in Galactic high-velocity clouds (HVCs) using archival ultraviolet (UV) spectra of extragalactic background sources. The UV data are obtained with the Cosmic Origins Spectrograph (COS) onboard the Hubble Space Telescope (HST) and are supplemented by 21 cm radio observations of neutral hydrogen. Methods: Along 270 sightlines we measure metal absorption in the lines of Si II, Si III, C II, and C iv and associated H I 21 cm emission in HVCs in the velocity range | vLSR | = 100-500 km s-1. With this unprecedented large HVC sample we were able to improve the statistics on HVC covering fractions, ionization conditions, small-scale structure, CGM mass, and inflow rate. For the first time, we determine robustly the angular two point correlation function of the high-velocity absorbers, systematically analyze antipodal sightlines on the celestial sphere, and compare the HVC absorption characteristics with that of damped Lyman α absorbers (DLAs) and constrained cosmological simulations of the LG (CLUES project). Results: The overall sky-covering fraction of high-velocity absorption is 77 ± 6 percent for the most sensitive ion in our survey, Si III, and for column densities log N(Si III)≥ 12.1. This value is 4-5 times higher than the covering fraction of 21 cm neutral hydrogen emission at log N(H I)≥ 18.7 along the same lines of sight, demonstrating that the Milky Way's CGM is multi-phase and predominantly ionized. The measured equivalent-width ratios of Si II, Si III, C II, and C iv are inhomogeneously distributed on large and small angular scales, suggesting a complex spatial distribution of multi-phase gas that surrounds the

  5. Influence of a sampling review process for radiation oncology quality assurance in cooperative group clinical trials -- results of the Radiation Therapy Oncology Group (RTOG) analysis

    International Nuclear Information System (INIS)

    Martin, Linda A.; Krall, John M.; Curran, Walter J.; Leibel, Steven A.; Cox, James D.

    1995-01-01

    The Radiation Therapy Oncology Group (RTOG) designed a random sampling process and observed its influence upon radiotherapy review mechanisms in cooperative group clinical trials. The method of sampling cases for review was modeled from sampling techniques commonly used in pharmaceutical quality assurance programs, and applied to the initial (on-study) review of protocol cases. 'In control' (IC) status is defined for a given facility as the ability to meet minimum compliance standards. Upon achieving IC status, activation of the sampling process was linked to the rate of continued patient accrual for each participating institution in a given protocol. The sampling design specified that ≥ 30% cases not in compliance would be detected with 80% power. A total of 458 cases was analyzed for initial review findings in four RTOG Phase III protocols. Initial review findings were compared with retrospective (final) review results. Of the 458 cases analyzed, 370 underwent initial review at on-study, while 88 did not require review as they were enrolled from institutions that had demonstrated protocol compliance. In the group that had both initial and final review, (345(370)) (93%) were found to have followed the protocol or had a minor variation. Of the exempted cases, (79(88)) (90%) were found to be per protocol or a minor variant. The sampling process proved itself to be cost-effective and resulted in a noticeable reduction in the workload, thus providing an improved approach to resource allocation for the group. Continued evaluation of the sampling mechanism is appropriate as study designs and participants vary over time, and as more data become available to study. Further investigation of individual protocol compliance is appropriate to identify problems specific to new trial investigations

  6. Implementation of Remote 3-Dimensional Image Guided Radiation Therapy Quality Assurance for Radiation Therapy Oncology Group Clinical Trials

    Energy Technology Data Exchange (ETDEWEB)

    Cui Yunfeng [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Galvin, James M. [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Radiation Therapy Oncology Group, American College of Radiology, Philadelphia, Pennsylvania (United States); Parker, William [Department of Medical Physics, McGill University Health Center, Montreal, QC (Canada); Breen, Stephen [Department of Radiation Physics, Princess Margaret Hospital, Toronto, ON (Canada); Yin Fangfang; Cai Jing [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Papiez, Lech S. [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Li, X. Allen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Bednarz, Greg [Department of Radiation Oncology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States); Chen Wenzhou [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Xiao Ying, E-mail: ying.xiao@jefferson.edu [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Radiation Therapy Oncology Group, American College of Radiology, Philadelphia, Pennsylvania (United States)

    2013-01-01

    Purpose: To report the process and initial experience of remote credentialing of three-dimensional (3D) image guided radiation therapy (IGRT) as part of the quality assurance (QA) of submitted data for Radiation Therapy Oncology Group (RTOG) clinical trials; and to identify major issues resulting from this process and analyze the review results on patient positioning shifts. Methods and Materials: Image guided radiation therapy datasets including in-room positioning CT scans and daily shifts applied were submitted through the Image Guided Therapy QA Center from institutions for the IGRT credentialing process, as required by various RTOG trials. A centralized virtual environment is established at the RTOG Core Laboratory, containing analysis tools and database infrastructure for remote review by the Physics Principal Investigators of each protocol. The appropriateness of IGRT technique and volumetric image registration accuracy were evaluated. Registration accuracy was verified by repeat registration with a third-party registration software system. With the accumulated review results, registration differences between those obtained by the Physics Principal Investigators and from the institutions were analyzed for different imaging sites, shift directions, and imaging modalities. Results: The remote review process was successfully carried out for 87 3D cases (out of 137 total cases, including 2-dimensional and 3D) during 2010. Frequent errors in submitted IGRT data and challenges in the review of image registration for some special cases were identified. Workarounds for these issues were developed. The average differences of registration results between reviewers and institutions ranged between 2 mm and 3 mm. Large discrepancies in the superior-inferior direction were found for megavoltage CT cases, owing to low spatial resolution in this direction for most megavoltage CT cases. Conclusion: This first experience indicated that remote review for 3D IGRT as part of QA

  7. Introduction of various amine groups onto polyethylene bead prepared by radiation-induced polymerization

    International Nuclear Information System (INIS)

    Kim, M.S.; Choi, S.H.; Lee, K.P.

    2002-01-01

    Complete text of publication follows. Radiation-induced graft polymerization is a good method for modification of chemical and physical properties of polymeric materials because it can endow properties such as membrane quality, ion exchange, blood compatibility, dyeability, protein adsorption, and immobilization of bioactive materials. Polyethylene microbead is very useful material due to the following advantages; low price, simple purchase, high sensitivity, and simple analysis. On the other hand, the epoxy group of the glycidyl methacrylate (GMA) can easily be converted to the various functional groups such as amines, alcohols, phosphoric acid, sulfonic acid, and amino acid, etc. Cyclodextrin have been applied universally in various industries such as foods, cosmetics, pharmaceutical industry, analytical chemistry, and chemical industry. In order to obtain cyclodextrins, polyethylene microbead with the epoxy group were prepared by radiation-induced graft polymerization of GMA onto polyethylene microbead. The physical and chemical properties of the GMA-induced polyethylene microbeads were investigated by IR, thermal analysis (TGA/DSC), and SEM, respectively. Subsequently, the various amine groups such as diethylamine. diethylenetriamine, triethylamine, triethylenetetramine, and 1,6-hexanediamine were induced onto the epoxy group in polyethylene microbead. Finally, cyclodextrin glucanotransferase were immobilized onto polyethylene microbead with various amines under the various experimental conditions, such as pH, amin content, immobilization time, and etc. The activity of CGTase-immobilized polyethylene microbead was determined by Phenolphthein method. The production of the cyclodextrins from starch is in progress

  8. Post-prostatectomy radiation therapy: Consensus guidelines of the Australian and New Zealand Radiation Oncology Genito-Urinary Group

    International Nuclear Information System (INIS)

    Sidhom, Mark A.; Kneebone, Andrew B.; Lehman, Margot; Wiltshire, Kirsty L.; Millar, Jeremy L.; Mukherjee, Rahul K.; Shakespeare, Thomas P.; Tai, Keen-Hun

    2008-01-01

    Background and purpose: Three randomised trials have demonstrated the benefit of adjuvant post-prostatectomy radiotherapy (PPRT) for high risk patients. Data also documents the effectiveness of salvage radiotherapy following a biochemical relapse post-prostatectomy. The Radiation Oncology Genito-Urinary Group recognised the need to develop consensus guidelines on to whom, when and how to deliver PPRT. Materials and methods: Draft guidelines were developed and refined at a consensus conference in June 2006 attended by 63 delegates where urological, radiotherapy and diagnostic imaging experts spoke on aspects of PPRT. Unresolved issues were further developed by working parties and redistributed until consensus was reached. Results: Central to the recommendations is that patients with positive surgical margins, seminal vesicle invasion and/or extracapsular extension have a high risk of residual local disease and should be informed of the options of either immediate adjuvant radiotherapy or active surveillance with early salvage in the event of biochemical recurrence. Salvage radiotherapy should be instituted at the earliest confirmation of biochemical recurrence. Detailed contouring guidelines have been developed, defining the regions at risk of residual microscopic disease which should be included in the clinical target volume. The recommended doses are 60-64 Gy for adjuvant, and 60-66 Gy for salvage radiotherapy. The role of hormone therapy in conjunction with PPRT is yet to be defined. Conclusions: These consensus guidelines have been developed to give clinical and technical guidance to radiation oncologists and urologists in the management of high risk post-prostatectomy patients

  9. Effects of gamma radiation on banana 'nanica' (Musa sp., group AAA) irradiated in pre climacteric phase

    International Nuclear Information System (INIS)

    Silva, Simone Faria; Dionisio, Ana Paula; Walder, Julio Marcos Melges

    2007-01-01

    The present work verified the effect of gamma radiation on physical and chemical parameters of banana 'nanica', analyzing possible alterations on the period of conservation and the possibility of commercial irradiation aiming the exportation. The results had demonstrated that the radiations had not produced effect on pH and total acidity. However, the bananas of the 'control group' and those that had received 0,75 kGy, had presented greater maturation degree and, radiated with 0,30 kGy, had presented greater firmness. In accordance with the results of the organoleptic analysis, can be perceived that the bananas most mature, especially of the 'control group', had had greater acceptance. The bananas of treatments 0,30 and 0,60 kGy had had minors notes for presenting minor maturation stadium. Knowing that the irradiation in adequate dose and fruits of good quality brings benefits to the storage and the process of exportation, we conclude that the dose most appropriate for the control of the maturation of the 'nanica' banana is 0,30 kGy. (author)

  10. Penetrating heavy ion charge and velocity discrimination with a TimePix-based Si detector (for space radiation applications)

    Energy Technology Data Exchange (ETDEWEB)

    Pinsky, Lawrence S., E-mail: pinsky@uh.edu [University of Houston, 4800 Calhoun Blvd., Houston, TX 77204-5005 (United States); Empl, Anton [University of Houston, 4800 Calhoun Blvd., Houston, TX 77204-5005 (United States); Gutierrez, Andrea [University of Montreal, 2905 Chemin des services, Montreal, Que., H3T 1J4 (Canada); Jakubek, Jan [Institute of Experimental and Applied Physics, Czech Technical University, Horska 3a/22, CZ-12800 Prague 2-Albertov (Czech Republic); Kitamura, Hisashi [National Institute for Radiological Sciences, Anagawa 4-9-1, Inage, Chiba 263-8555 (Japan); Miller, Jack [Space Sciences Laboratory, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Leroy, Claude [University of Montreal, 2905 Chemin des services, Montreal, Que., H3T 1J4 (Canada); Stoffle, Nicholas [University of Houston, 4800 Calhoun Blvd., Houston, TX 77204-5005 (United States); Pospisil, Stanislav [Institute of Experimental and Applied Physics, Czech Technical University, Horska 3a/22, CZ-12800 Prague 2-Albertov (Czech Republic); Uchihori, Yukio; Yasuda, Nakahiro [National Institute for Radiological Sciences, Anagawa 4-9-1, Inage, Chiba 263-8555 (Japan); Zeitlin, Cary [Southwest Research Institute, 6220 Culebra Rd., San Antonio, TX 78238-5166 (United States)

    2011-05-15

    Exposures were made with Medipix2 TimePix-based Si detectors at the HIMAC facility in Japan to explore the potential for discrimination between tracks with differing charges and energies, but with very similar dE/dx values. Data were taken at 15 deg. increments for a number of different beams including 600 and 800 MeV/A Si, 180 MeV/A Ne and 100 MeV/A O. Data were also obtained for 400 MeV/A Si and 500 MeV/A Fe along with 290 and 180 MeV/A N. The TimePix chips have been calibrated to achieve the maximum resolution. Estimates for the angular resolution for these types of tracks are also possible from these data, which are essential in the development of a TimePix-based dosimetric device for use in a space radiation environment. One of the principal objectives of these data runs was to explore the resolution of TimePix-based Si detectors to discriminate between various ions with different energies and charges, but with similar dE/dx values in Si. Analysis of the images obtained shows the clear differences in the {delta}-ray halos for particles with similar dE/dx values but for differing charges and energies. These measurements are part of an ongoing program to explore the range of capabilities of the TimePix-based detector with respect to dosimetry uses in space.

  11. Radiative corrections to e+e- reactions to all orders in α using the renormalization group

    International Nuclear Information System (INIS)

    Tsai, Y.S.

    1983-01-01

    Renormalization group technique is used to improve the accuracy of the lowest order radiative corrections in QED. The exponentiation of infrared terms comes automatically. It also leads to exponentiation of the vertex functions. It predicts the existence of conversion of photons into pairs and the result agrees with the Kroll-Wada relation. Kinoshita-Lee-Nauenberg cancellation of mass singularities occurs to all order in α in leading log approximation in the final state if we sum over all the final states. Higher order corrections to the order α 3 asymmetry is shown to be small. The results are used to derive useful formulas for the radiative corrections to processes such as e + e - → μ + μ - , e + e - → μ + μ - γ, e + e - → hadron continuum, e + e - → very narrow resonance such as phi, and e + e - → not very narrow resonance such as Z 0

  12. Development of identification process for insect group using radiation marker DNA

    International Nuclear Information System (INIS)

    Muraji, M.; Tamura, T.

    2004-01-01

    Detection of a band pattern for insect groups was tried by using radiation marked DNA clone. A rapid segregation process for poly-type DNA segment was investigated. A band pattern of silkworm was detected by analysis using DNA type transposon, K1.4. The exon regions on genes of hemiptera insect were segregated by in vitro cloning. Band patterns of the silkworm and the other insects were detected by identification process of DNA clone and radiation marker. Family singularity mutation existed in the inserted position of transposon. The family of insect was identified easily by the difference of the detection band patterns. Effective band pattern for family discrimination were obtained by analysis for a part of mitochondria DNA and ribosomal DNA. DNA segregation process was investigated by using the enriched library, also. (M. Suetake)

  13. Radioprotective effect of sulphydryl group containing triazole derivative to modulate the radiation-induced clastogenic effects

    International Nuclear Information System (INIS)

    Suchetha Kumari, N.; Madhu, L.N.

    2012-01-01

    Protection of biological systems against radiation damage is of paramount importance during accidental and unavoidable exposure to radiation. Several physico-chemical and biological factors collectively contribute to the damage caused by radiation and are, therefore, targets for developing radioprotectors. Chemicals capable of scavenging free radicals, relieving oxidative stress, promoting antioxidant activity and modulating immune response have been some of the radioprotectors extensively investigated with limited success. It has long been known that some of the most effective radioprotective agents are those which contain sulphydryl groups. The present study reports an evaluation of radical scavenging property and radioprotective property of sulphydryl group containing triazole derivative. The lethal dose of Electron beam radiation (EBR) was studied by survival assay. The dose reduction factor (DRF) of 4-amino-5-mercapto-3-methyl-1,2,4-triazole (TR1) was calculated by taking the ratio between LD 50 of EBR with and without TR1 treatment. Radical scavenging property of TR1 was assessed by DPPH radical scavenging assay. The clastogenic effects of EBR were recorded by Micronucleus test in bone marrow cells and DNA fragmentation assay in hepatic cells of mice. The survival assay results showed that 10Gy was the LD 50 of EBR. The calculated DRF for TR1 was found to be 1.2. DPPH radical scavenging assay showed a positive result when it compared with the standard glutathione. Treatment of mice with 100 mg of TR1 for 15 days before irradiation significantly (P<0.05) reduced the frequency of micronucleus formation in bone marrow cells and also reduced the DNA fragmentation in hepatic cells. The result obtained in the present study concludes that TR1 has a protective effect against the EBR-induced mortality and clastogenicity. (author)

  14. Defining fitness to practise in Australian radiation therapy: A focus group study

    International Nuclear Information System (INIS)

    Wright, Caroline A.; Jolly, Brian; Schneider-Kolsky, Michal E.; Baird, Marilyn A.

    2011-01-01

    Purpose: This paper presents the results of a study undertaken to investigate how Australian radiation therapists define fitness to practise. Method: A qualitative approach was taken to data collection with focus groups being employed to gather the data. Analysis was informed by grounded theory. Following ethics approval, three homogeneous focus groups were conducted comprising a total of 21 participants, with 5-8 participants per group. The discussions were transcribed, verified by the researcher and participants, then unitised, coded and a sample checked by a second coder. Findings: There was no consensus on the definition of fitness to practise. The terms professionalism and competence were used interchangeably in some definitions. Four themes emerged from the data, these were; fitness as a continuum (individual differences and longevity in the profession), fitness as behaviour and conduct (professionalism and competence), fitness as a state of mind (attitudes and intangible elements) and fitness as being qualified (course completion means fitness to practise). Three concepts which were not raised were illegal behaviour, impaired practice and dose errors. Conclusion: There is no consensus among radiation therapists about fitness to practise. There was confusion with how Fitness to practise relates to professionalism and competence with little mention of how impairment is interwoven into the notion of fitness to practise. Without an unambiguous definition and robust criteria, making the 'judgement call' as to whether a practitioners' fitness to practise is impaired will continue to be a challenge for educators, departmental managers and registration boards.

  15. Defining fitness to practise in Australian radiation therapy: A focus group study

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Caroline A., E-mail: caroline.wright@med.monash.edu.a [Monash University, Medical Imaging and Radiation Sciences, Clayton Campus, Wellington Road Clayton, Melbourne, Victoria 3800 (Australia); Jolly, Brian [Monash University, Centre for Medical and Health Sciences Education (Australia); Schneider-Kolsky, Michal E.; Baird, Marilyn A. [Monash University, Medical Imaging and Radiation Sciences, Clayton Campus, Wellington Road Clayton, Melbourne, Victoria 3800 (Australia)

    2011-02-15

    Purpose: This paper presents the results of a study undertaken to investigate how Australian radiation therapists define fitness to practise. Method: A qualitative approach was taken to data collection with focus groups being employed to gather the data. Analysis was informed by grounded theory. Following ethics approval, three homogeneous focus groups were conducted comprising a total of 21 participants, with 5-8 participants per group. The discussions were transcribed, verified by the researcher and participants, then unitised, coded and a sample checked by a second coder. Findings: There was no consensus on the definition of fitness to practise. The terms professionalism and competence were used interchangeably in some definitions. Four themes emerged from the data, these were; fitness as a continuum (individual differences and longevity in the profession), fitness as behaviour and conduct (professionalism and competence), fitness as a state of mind (attitudes and intangible elements) and fitness as being qualified (course completion means fitness to practise). Three concepts which were not raised were illegal behaviour, impaired practice and dose errors. Conclusion: There is no consensus among radiation therapists about fitness to practise. There was confusion with how Fitness to practise relates to professionalism and competence with little mention of how impairment is interwoven into the notion of fitness to practise. Without an unambiguous definition and robust criteria, making the 'judgement call' as to whether a practitioners' fitness to practise is impaired will continue to be a challenge for educators, departmental managers and registration boards.

  16. Radiation Therapy Planning for Early-Stage Hodgkin Lymphoma: Experience of the International Lymphoma Radiation Oncology Group

    International Nuclear Information System (INIS)

    Maraldo, Maja V.; Dabaja, Bouthaina S.; Filippi, Andrea R.; Illidge, Tim; Tsang, Richard; Ricardi, Umberto; Petersen, Peter M.; Schut, Deborah A.; Garcia, John; Headley, Jayne; Parent, Amy; Guibord, Benoit; Ragona, Riccardo; Specht, Lena

    2015-01-01

    Purpose: Early-stage Hodgkin lymphoma (HL) is a rare disease, and the location of lymphoma varies considerably between patients. Here, we evaluate the variability of radiation therapy (RT) plans among 5 International Lymphoma Radiation Oncology Group (ILROG) centers with regard to beam arrangements, planning parameters, and estimated doses to the critical organs at risk (OARs). Methods: Ten patients with stage I-II classic HL with masses of different sizes and locations were selected. On the basis of the clinical information, 5 ILROG centers were asked to create RT plans to a prescribed dose of 30.6 Gy. A postchemotherapy computed tomography scan with precontoured clinical target volume (CTV) and OARs was provided for each patient. The treatment technique and planning methods were chosen according to each center's best practice in 2013. Results: Seven patients had mediastinal disease, 2 had axillary disease, and 1 had disease in the neck only. The median age at diagnosis was 34 years (range, 21-74 years), and 5 patients were male. Of the resulting 50 treatment plans, 15 were planned with volumetric modulated arc therapy (1-4 arcs), 16 with intensity modulated RT (3-9 fields), and 19 with 3-dimensional conformal RT (2-4 fields). The variations in CTV-to-planning target volume margins (5-15 mm), maximum tolerated dose (31.4-40 Gy), and plan conformity (conformity index 0-3.6) were significant. However, estimated doses to OARs were comparable between centers for each patient. Conclusions: RT planning for HL is challenging because of the heterogeneity in size and location of disease and, additionally, to the variation in choice of treatment techniques and field arrangements. Adopting ILROG guidelines and implementing universal dose objectives could further standardize treatment techniques and contribute to lowering the dose to the surrounding OARs

  17. Interagency task force on the health effects of ionizing radiation: report of the work group on public information

    International Nuclear Information System (INIS)

    1979-06-01

    The health effects of ionizing radiation recently have been the focus of increased public concern. In response to this concern, in a May 9, 1978, memorandum the White House requested the Secretary of Health, Education, and Welfare to coordinate an interagency program that would, among other things, ensure public awareness and knowledge of the health effects of ionizing radiation. As a result, the Interagency Task Force on Ionizing Radiation was formed. The Information Work Group of the Task Force was asked to outline a public information program to meet the needs of the general public, the health and scientific community, workers, and other persons exposed to low levels of ionizing radiation in the past and at present or who may be exposed in the future. The Work Group is composed of 16 members, each representing an agency participating on the Interagency Task Force on Ionizing Radiation. The Work Group members used the draft Reports of the Science Work Group, the Radiation Exposure Reduction Work Group, the Care and Benefits Work Group, and the Privacy Work Group as a basis for developing the Information Report. In addition, the Information Work Group conducted a preliminary review of existing federal information programs. Meetings were held with representatives of environmental and trade groups, unions, and professional societies to help define the dimensions and priorities of a public information program

  18. Epidemiological studies of general population groups exposed to low-level radiation

    International Nuclear Information System (INIS)

    Davies, J.M.; Inskip, H.

    1986-01-01

    The exposure of man to radiation and the resulting risk of carcinogenesis continue to be of concern to the public. In this context, there is often a tendency to carry out epidemiological studies concerning the induction of cancer in radiation workers and members of the public which are not supported by a statistically valid data base or whose result are misinterpreted or misused. To assist national authorities in evaluating radiological risks, the Nuclear Energy Agency has sponsored a critical review of the methodologies for, and the limitations of, these epidemiological studies, and of the precautions to be adopted in interpreting their results. Prepared by two consultants, Dr. Joan M. Davies and Dr. Hazel Inskip, the review focuses on the problems encountered when carrying out epidemiological studies on groups of the general population exposed to radiation, and using their results for radiological protection purposes. The primary objective is to provide background material for national authorities who have responsibilities in the field of radiological protection, as well as to other persons interested in this subject. It is published under the responsibility of the Secretary General of the OECD, and does not necessarily reflect the views of Member Governments

  19. Crosslink the Novel Group of Polymeric Binders BioCo by the UV-radiation

    Directory of Open Access Journals (Sweden)

    Grabowska B.

    2016-06-01

    Full Text Available The spectroscopic FT-IR and FT-Raman methods allowed to identify the cross-linking process of the aqueous composition of poly(acrylic acid/sodium salt of carboxymethyl starch (PAA/CMS-Na applied as a binder for moulding sands (as a novel group binders BioCo. The cross-linking was performed by physical agent, applying the UV-radiation. The results of structural studies (IR, Raman confirm the overlapping of the process of cross-linking polymer composition PAA/CMS-Na in UV radiation. Taking into account the ingredients and structure of the polymeric composition can also refer to a curing process in a binder - mineral matrix mixture. In the system of binder-mineral matrix under the influence of ultraviolet radiation is also observed effect of binding. However, the bonding process does not occur in the entire volume of the investigated system, but only on the surface, which gives some possibilities for application in the use of UV curing surface of cores, and also to cure sand moulds in 3D printing technology.

  20. Radiation dosimetry in digital breast tomosynthesis: Report of AAPM Tomosynthesis Subcommittee Task Group 223

    Energy Technology Data Exchange (ETDEWEB)

    Sechopoulos, Ioannis, E-mail: isechop@emory.edu [Departments of Radiology and Imaging Sciences, Hematology and Medical Oncology and Winship Cancer Institute, Emory University, 1701 Uppergate Drive Northeast, Suite 5018, Atlanta, Georgia 30322 (United States); Sabol, John M. [GE Healthcare, Global Diagnostic X-Ray, Mailstop W-701, 3000 North Grandview Boulevard, Waukesha, Wisconsin 53188 (United States); Berglund, Johan [Research and Development, Philips Women' s Healthcare, Solna (Sweden); Bolch, Wesley E. [J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, Florida 32611 (United States); Brateman, Libby [University of Florida, Gainesville, Florida 32611 (United States); Christodoulou, Emmanuel; Goodsitt, Mitchell [Department of Radiology, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109 (United States); Flynn, Michael [Department of Radiology, Henry Ford Health System, Radiology Research 2F, 1 Ford Place, Detroit, Michigan 48202 (United States); Geiser, William [Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030-4009 (United States); Kyle Jones, A. [Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Lo, Joseph Y.; Paul Segars, W. [Department of Radiology, Medical Physics Graduate Program, and Department of Biomedical Engineering, Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 (United States); Maidment, Andrew D. A. [Department of Radiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104-4206 (United States); Nishino, Kazuyoshi [R and D X-ray Products Group, Shimadzu Corporation, Tokyo (Japan); Nosratieh, Anita [Biomedical Engineering Graduate Group, Department of Radiology, University of California, Davis, California 95817 (United States); and others

    2014-09-15

    The radiation dose involved in any medical imaging modality that uses ionizing radiation needs to be well understood by the medical physics and clinical community. This is especially true of screening modalities. Digital breast tomosynthesis (DBT) has recently been introduced into the clinic and is being used for screening for breast cancer in the general population. Therefore, it is important that the medical physics community have the required information to be able to understand, estimate, and communicate the radiation dose levels involved in breast tomosynthesis imaging. For this purpose, the American Association of Physicists in Medicine Task Group 223 on Dosimetry in Tomosynthesis Imaging has prepared this report that discusses dosimetry in breast imaging in general, and describes a methodology and provides the data necessary to estimate mean breast glandular dose from a tomosynthesis acquisition. In an effort to maximize familiarity with the procedures and data provided in this Report, the methodology to perform the dose estimation in DBT is based as much as possible on that used in mammography dose estimation.

  1. Radiation dosimetry in digital breast tomosynthesis: Report of AAPM Tomosynthesis Subcommittee Task Group 223

    International Nuclear Information System (INIS)

    Sechopoulos, Ioannis; Sabol, John M.; Berglund, Johan; Bolch, Wesley E.; Brateman, Libby; Christodoulou, Emmanuel; Goodsitt, Mitchell; Flynn, Michael; Geiser, William; Kyle Jones, A.; Lo, Joseph Y.; Paul Segars, W.; Maidment, Andrew D. A.; Nishino, Kazuyoshi; Nosratieh, Anita

    2014-01-01

    The radiation dose involved in any medical imaging modality that uses ionizing radiation needs to be well understood by the medical physics and clinical community. This is especially true of screening modalities. Digital breast tomosynthesis (DBT) has recently been introduced into the clinic and is being used for screening for breast cancer in the general population. Therefore, it is important that the medical physics community have the required information to be able to understand, estimate, and communicate the radiation dose levels involved in breast tomosynthesis imaging. For this purpose, the American Association of Physicists in Medicine Task Group 223 on Dosimetry in Tomosynthesis Imaging has prepared this report that discusses dosimetry in breast imaging in general, and describes a methodology and provides the data necessary to estimate mean breast glandular dose from a tomosynthesis acquisition. In an effort to maximize familiarity with the procedures and data provided in this Report, the methodology to perform the dose estimation in DBT is based as much as possible on that used in mammography dose estimation

  2. Radiation oncology training in the United States: report from the Radiation Oncology Resident Training Working Group organized by the Society of Chairman of Academic Radiation Oncology Programs (SCAROP)

    International Nuclear Information System (INIS)

    1999-01-01

    Purpose: In response to the major changes occurring in healthcare, medical education, and cancer research, SCAROP addressed issues related to post-graduate education that could enhance existing programs and complement the present system. Methods and Materials: SCAROP brought together a Working Group with a broad range of representatives organized in subcommittees to address: training, curriculum, and model building. Results: The Working Group emphasized the importance of training physicians with the necessary clinical, scientific, and analytical skills, and the need to provide expert radiation oncology services to patients throughout the United States. Opportunities currently exist for graduates in academic medicine, although there may be limited time and financial resources available to support academic pursuits. Conclusions: In the face of diminishing resources for training and education and the increased scope of knowledge required, a number of models for resident training are considered that can provide flexibility to complement the present system. This report is intended to initiate dialogue among the organizations responsible for radiation oncology resident education so that resident training can continually evolve to meet the needs of cancer patients and take advantage of opportunities for progress through innovative cancer care and research

  3. Filamentation and light bullet formation dynamics in solid-state dielectric media with weak, moderate and strong anomalous group velocity dispersion

    International Nuclear Information System (INIS)

    Gražulevičiūtė, I; Garejev, N; Majus, D; Tamošauskas, G; A Dubietis; Jukna, V

    2016-01-01

    We present a series of measurements, which characterize filamentation dynamics of intense ultrashort laser pulses in the space–time domain, as captured by means of three-dimensional imaging technique in sapphire and fused silica, in the wavelength range of 1.45–2.25 μm, accessing the regimes of weak, moderate and strong anomalous group velocity dispersion (GVD). In the regime of weak anomalous GVD (at 1.45 μm), pulse splitting into two sub-pulses producing a pair of light bullets with spectrally shifted carrier frequencies in both nonlinear media is observed. In contrast, in the regimes of moderate (at 1.8 μm) and strong (at 2.25 μm) anomalous GVD we observe notably different transient dynamics, which however lead to the formation of a single self-compressed quasistationary light bullet with an universal spatiotemporal shape comprised of an extended ring-shaped periphery and a localized intense core that carries the self-compressed pulse. (paper)

  4. Filamentation and light bullet formation dynamics in solid-state dielectric media with weak, moderate and strong anomalous group velocity dispersion

    Science.gov (United States)

    Gražulevičiūtė, I.; Garejev, N.; Majus, D.; Jukna, V.; Tamošauskas, G.; Dubietis, A.

    2016-02-01

    We present a series of measurements, which characterize filamentation dynamics of intense ultrashort laser pulses in the space-time domain, as captured by means of three-dimensional imaging technique in sapphire and fused silica, in the wavelength range of 1.45-2.25 μm, accessing the regimes of weak, moderate and strong anomalous group velocity dispersion (GVD). In the regime of weak anomalous GVD (at 1.45 μm), pulse splitting into two sub-pulses producing a pair of light bullets with spectrally shifted carrier frequencies in both nonlinear media is observed. In contrast, in the regimes of moderate (at 1.8 μm) and strong (at 2.25 μm) anomalous GVD we observe notably different transient dynamics, which however lead to the formation of a single self-compressed quasistationary light bullet with an universal spatiotemporal shape comprised of an extended ring-shaped periphery and a localized intense core that carries the self-compressed pulse.

  5. Radiation-chemical synthesis of polypropylene fabrics with sulfonic acid functional groups

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Hyun Kug; Park, Jung Soo; Han, Do Hung, E-mail: dhhan@yumail.ac.kr; Bondar, Iuliia, E-mail: juliavad@yahoo.co

    2011-04-01

    A sorption-active material carrying sulfonic acid groups was synthesized by the radiation-induced graft polymerization of styrene monomer onto the surface of non-woven polypropylene fabric, followed by sulfonation of the grafted polystyrene chains. The effect of the main experimental parameters (absorbed dose, monomer concentration, reaction time) on the styrene degree of grafting was investigated. The sulfonation process with 5% chlorosulfonic acid at room temperature was investigated in detail and the optimal sulfonation conditions for the samples with a medium degree of grafting (70-140%) were determined. Densities of 3.5-5 meq/g were obtained by applying those sorption-active PP fabrics with a sulfonic acid group.

  6. Current technological clinical practice in breast radiotherapy; results of a survey in EORTC-Radiation Oncology Group affiliated institutions

    NARCIS (Netherlands)

    van der Laan, Hans Paul; Hurkmans, Coen W; Kuten, Abraham; Westenberg, Helen A

    PURPOSE: To evaluate the current technological clinical practice of radiation therapy of the breast in institutions participating in the EORTC-Radiation Oncology Group (EORTC-ROG). MATERIALS AND METHODS: A survey was conducted between August 2008 and January 2009 on behalf of the Breast Working

  7. The quality of radiation care: the results of focus group interviews and concept mapping to explore the patient's perspective.

    NARCIS (Netherlands)

    Nijman, J.L.; Sixma, H.; Triest, B. van; Keus, R.B.; Hendriks, M.

    2012-01-01

    Background and purpose: In this study, we explore the quality aspects of radiation care from the patient’s perspective in order to develop a draft Consumer Quality Index (CQI) Radiation Care instrument. Materials and methods: Four focus group discussions with (former) cancer patients were held to

  8. Adaptive Radiation in Socially Advanced Stem-Group Ants from the Cretaceous.

    Science.gov (United States)

    Barden, Phillip; Grimaldi, David A

    2016-02-22

    Across terrestrial ecosystems, modern ants are ubiquitous. As many as 94 out of every 100 individual arthropods in rainforests are ants, and they constitute up to 15% of animal biomass in the Amazon. Moreover, ants are pervasive agents of natural selection as over 10,000 arthropod species are specialized inquilines or myrmecomorphs living among ants or defending themselves through mimicry. Such impact is traditionally explained by sociality: ants are the first major group of ground-dwelling predatory insects to become eusocial, increasing efficiency of tasks and establishing competitive superiority over solitary species. A wealth of specimens from rich deposits of 99 million-year-old Burmese amber resolves ambiguity regarding sociality and diversity in the earliest ants. The stem-group genus Gerontoformica maintained distinct reproductive castes including morphotypes unknown in solitary aculeate (stinging) wasps, providing insight into early behavior. We present rare aggregations of workers, indicating group recruitment as well as an instance of interspecific combat; such aggression is a social feature of modern ants. Two species and an unusual new genus are described, further expanding the remarkable diversity of early ants. Stem-group ants are recovered as a paraphyletic assemblage at the base of modern lineages varying greatly in size, form, and mouthpart structure, interpreted here as an adaptive radiation. Though Cretaceous stem-group ants were eusocial and adaptively diverse, we hypothesize that their extinction resulted from the rise of competitively superior crown-group taxa that today form massive colonies, consistent with Wilson and Hölldobler's concept of "dynastic succession." Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Influence of high doses gamma radiation on group of meadow plants and water organisms

    International Nuclear Information System (INIS)

    Wlodek, St.; Wasilewski, A.; Indeka, L.; Kobuszewska, B.; Krzysztofik, B.; Ossowska-Cypryk, K.; Slomczynski, T.

    1979-01-01

    The plot of 100 square meters area has been irradiated for 526 days by gamma radiation which simulated the external radiation of the local fall-out. This field experiment has been performed in specially preserved conditions. The organisms of land and water complexes present in this area have received the total of 50 000 R in the center and 600 R on periphery. It has been shown that: changes in the quantitative and qualitative composition of bacteria and soil and water fungi were generally little: among the physiological groups the greatest disfunctions have been observed for the bacteria of the nitric cycle; Lemna minor appeared to be the most radiosensitive water plant which perished completely in the zone around the center of the plot what in turn resulted in secondary changes in the composition of water microflora and micro- and macrofauna; the growth of 14 species of meadow plants present around the center of the plot has been reduced about 25% of biomass in comparison with the control plots; on the other hand, the stimulation of growth of meadow plants, mostly weeds, has been observed on the periphery of the plot. (author)

  10. Influence of high doses gamma radiation on group of meadow plants and water organisms

    Energy Technology Data Exchange (ETDEWEB)

    Wlodek, St; Wasilewski, A; Indeka, L; Kobuszewska, B; Krzysztofik, B; Ossowska-Cypryk, K; Slomczynski, T

    1979-01-01

    The plot of 100 square meters area has been irradiated for 526 days by gamma radiation which simulated the external radiation of the local fall-out. This field experiment has been performed in specially preserved conditions. The organisms of land and water complexes present in this area have received the total of 50 000 R in the center and 600 R on periphery. It has been shown that: changes in the quantitative and qualitative composition of bacteria and soil and water fungi were generally little: among the physiological groups the greatest disfunctions have been observed for the bacteria of the nitric cycle; Lemna minor appeared to be the most radiosensitive water plant which perished completely in the zone around the center of the plot what in turn resulted in secondary changes in the composition of water microflora and micro- and macrofauna; the growth of 14 species of meadow plants present around the center of the plot has been reduced about 25% of biomass in comparison with the control plots; on the other hand, the stimulation of growth of meadow plants, mostly weeds, has been observed on the periphery of the plot.

  11. Cancer pain management by radiotherapists: a survey of radiation therapy oncology group physicians

    International Nuclear Information System (INIS)

    Cleeland, Charles S.; Janjan, Nora A.; Scott, Charles B.; Seiferheld, Wendy F.; Curran, Walter J.

    2000-01-01

    Purpose: Radiation Therapy Oncology Group (RTOG) physicians were surveyed to determine their approach to and attitudes toward cancer pain management. Methods and Materials: Physicians completed a questionnaire assessing their estimates of the magnitude of pain as a specific problem for cancer patients, their perceptions of the adequacy of pain management, and their report of how they manage pain in their own practice setting. Results: Eighty-three percent believed the majority of cancer patients with pain were undermedicated. Forty percent reported that pain relief in their own practice setting was poor or fair. Assessing a case scenario, 23% would wait until the patient's prognosis was 6 months or less before starting maximal analgesia. Adjuvants and prophylactic side effect management were underutilized in the treatment plan. Barriers to pain management included poor pain assessment (77%), patient reluctance to report pain (60%), patient reluctance to take analgesics (72%), and staff reluctance to prescribe opioids (41%). Conclusions: Physicians' perceptions of barriers to cancer pain management remain quite stable over time, and physicians continue to report inadequate pain treatment education. Future educational efforts should target radiation oncologists as an important resource for the treatment of cancer pain

  12. Final report of the group research. Genome analysis on the biological effects of radiation. Second research group of NIRS

    International Nuclear Information System (INIS)

    2001-10-01

    This report concerns investigations on the title conducted by 5 subgroups of National Institute of Radiological Sciences (NIRS) during the period of 1993-2001. The report involves the organization of research teams and summary reports from the subgroups for Genome sequencing and informatics, Genome analysis on model organisms, The genome analysis on the specific chromosomal region related to radiation-sensitivity, Molecular analysis on the structure and function of particular regions of human genome, and Generation and characterization of DNA repair-deficient model mice. Significant results are as follows: Sequencing of the radiation sensitivity gene ATM, finding of a novel cell cycle regulator gene NPAT and regulation of gene expression of ATM/NPAT; Findings that the cause of the variability related to instability of human genome is derived from particular repeat structures of 5 and 35 bases and of the instability mutation, from the mutation of EPILS (mRNA synthase gene); Program development for novel human genome finding in the DNA sequences and making novel human gene as a resource by polymerase chain reaction (PCR) technique; and generation of the highly UV-sensitive mouse model for human xeroderma pigmentosum G. Conclusion is that findings will contribute for better understanding of the genes functioning radiation sensitivity and also biodefense mechanism against radiation and other environmental stress. (N.I.)

  13. Introduction of functionalizable groups via radiation grafting into polymer electrolyte membranes for fuel cells

    International Nuclear Information System (INIS)

    Buchmueller, Y.; Scherer, G.G.; Wokaun, A.; Gubler, L.

    2011-01-01

    Complete text of publication follows. Our work is focused on the introduction of functionalizable groups, so called linkers, to polymer electrolyte membranes. The aim is to attach antioxidant groups to the linkers to enhance the durability of the proton conducting membrane in a fuel cell. The synthetic route we chose is radiation cografting of functionalizable monomers and precursor monomers of a protogenic group into ETFE base film (thickness 25 μm) with subsequent amination. Typically, we performed cografting of styrene with different linkers, such as acryloyl chloride, vinylbenzyl chloride, and glycidyl methacrylate. Styrene is readily sulfonated to introduce proton conductivity. The cografting behavior of the linkers and styrene was investigated to target the desired molar fraction of the monomers in the grafted polymer. All films were characterized by Fourier transform infrared (FTIR) spectroscopy and elemental analysis. Using these data the graft polymerization kinetics of these systems have been determined. The cografted films were first functionalized with amines, such as thyramine and dopamine, and then sulfonated or vice-versa, depending on the stability of the compounds in acidic environment. The synthesized membranes were characterized for conductivity and ion exchange capacity (IEC). Promising membranes were tested in a fuel cell.

  14. Atrophy of sacrospinal muscle groups in patients with chronic, diffusely radiating lumbar back pain

    Energy Technology Data Exchange (ETDEWEB)

    Laasonen, E.M.

    1984-01-01

    After surgery necessitated by lumbar back pain syndromes, radiolucency verified by CT may appear in the sacrospinal muscle group on the operate side. This radiolucency represents muscular atrophy and is in its most severe form a result of the replacement of muscle tissue with adipose tissue. Such muscular atrophy appeared in the present series in 31 out of all 156 patients (19.9%) and in 29 out of 94 patients operated on because of radiating lumbar back pain (30.9%). The radiological appearance, extent, and HU values of this muscular atrophy are presented in detail. Only weak correlations with the multitude of clinical symptoms and signs were found in this retrospective study. The effects of irreversible muscular atrophy on the indications for surgery and physiotherapy are discussed.

  15. Atrophy of sacrospinal muscle groups in patients with chronic, diffusely radiating lumbar back pain

    International Nuclear Information System (INIS)

    Laasonen, E.M.

    1984-01-01

    After surgery necessitated by lumbar back pain syndromes, radiolucency verified by CT may appear in the sacrospinal muscle group on the operate side. This radiolucency represents muscular atrophy and is in its most severe form a result of the replacement of muscle tissue with adipose tissue. Such muscular atrophy appeared in the present series in 31 out of all 156 patients (19.9%) and in 29 out of 94 patients operated on because of radiating lumbar back pain (30.9%). The radiological appearance, extent, and HU values of this muscular atrophy are presented in detail. Only weak correlations with the multitude of clinical symptoms and signs were found in this retrospective study. The effects of irreversible muscular atrophy on the indications for surgery and physiotherapy are discussed. (orig.)

  16. Rapid monitoring of large groups of internally contaminated people following a radiation accident

    International Nuclear Information System (INIS)

    1994-05-01

    In the management of an emergency, it is necessary to assess the radiation exposures of people in the affected areas. An essential component in the programme is the monitoring of internal contamination. Existing fixed installations for the assessment of incorporated radionuclides may be of limited value in these circumstances because they may be inconveniently sited, oversensitive for the purpose, or inadequately equipped and staffed to cope with the large numbers referred to them. The IAEA considered it important to produce guidance on rapid monitoring of large groups of internally contaminated people. The purpose of this document is to provide Member States with an overview on techniques that can be applied during abnormal or accidental situations. Refs and figs

  17. Serum pepsin levels Hiroshima adult health study. Relation to radiation, ABO blood groups, and gastrointestinal diseases

    Energy Technology Data Exchange (ETDEWEB)

    Knittle, J L

    1961-07-12

    At the ABCC clinic in Hiroshima 1330 subjects were investigated as to serum pepsin levels over a four month period. The normal mean values compared well with those reported for a United States population using a similar technique. There appeared to be no significant change in serum pepsin level with age, and no difference could be detected among individuals of the ABO blood groups. No relationship was found between serum pepsin level and exposure to ionizing radiation. Patients with gastric and duodenal ulcers had mean levels which were higher than normal mean values, while patients with leukemia had lower than normal mean levels. Patients with gastric polyps and gastric cancer had normal mean values. It is believed that the relation of serum pepsin activity to cancer of the stomach is not settled and deserves further investigation. 23 references, 2 figures, 4 tables.

  18. Feasibility of Economic Analysis of Radiation Therapy Oncology Group (RTOG) 91-11 Using Medicare Data

    International Nuclear Information System (INIS)

    Konski, Andre; Bhargavan, Mythreyi; Owen, Jean; Paulus, Rebecca; Cooper, Jay; Forastiere, Arlene; Ang, K. Kian; Watkins-Bruner, Deborah

    2011-01-01

    Purpose: The specific aim of this analysis was to evaluate the feasibility of performing a cost-effectiveness analysis using Medicare data from patients treated on a randomized Phase III clinical trial. Methods and Materials: Cost data included Medicare Part A and Part B costs from all providers-inpatient, outpatient, skilled nursing facility, home health, hospice, and physicians-and were obtained from the Centers for Medicare and Medicaid Services for patients eligible for Medicare, treated on Radiation Therapy Oncology Group (RTOG) 9111 between 1992 and 1996. The 47-month expected discounted (annual discount rate of 3%) cost for each arm of the trial was calculated in 1996 dollars, with Kaplan-Meier sampling average estimates of survival probabilities for each month and mean monthly costs. Overall and disease-free survival was also discounted 3%/year. The analysis was performed from a payer's perspective. Incremental cost-effectiveness ratios were calculated comparing the chemotherapy arms to the radiation alone arm. Results: Of the 547 patients entered, Medicare cost data and clinical outcomes were available for 66 patients. Reasons for exclusion included no RTOG follow-up, Medicare HMO enrollment, no Medicare claims since trial entry, and trial entry after 1996. Differences existed between groups in tumor characteristics, toxicity, and survival, all which could affect resource utilization. Conclusions: Although we were able to test the methodology of economic analysis alongside a clinical trial using Medicare data, the results may be difficult to translate to the entire trial population because of non-random missing data. Methods to improve Medicare data capture and matching to clinical trial samples are required.

  19. Sociodemographic analysis of patients in radiation therapy oncology group clinical trials

    International Nuclear Information System (INIS)

    Chamberlain, Robert M.; Winter, Kathryn A.; Vijayakumar, Srinivasan; Porter, Arthur T.; Roach, M.; Streeter, Oscar; Cox, James D.; Bondy, Melissa L.

    1998-01-01

    Purpose: To assess the degree to which the sociodemographic characteristics of patients enrolled in Radiation Therapy Oncology Group (RTOG) clinical trails are representative of the general population. Methods and Materials: Sociodemographic data were collected on 4016 patients entered in 33 open RTOG studies between July 1991 and June 1994. The data analyzed included educational attainment, age, gender, and race. For comparison, we obtained similar data from the U.S. Department of Census. We also compared our RTOG data with Surveillance Epidemiology and End Results (SEER) data for patients who received radiation therapy, to determine how RTOG patients compared with cancer patients in general, and with patients with cancers at sites typically treated with radiotherapy. Results: Overall, the sociodemographic characteristics of patients entered in RTOG trials were similar to those of the Census data. We found that, in every age group of African-American men and at nearly every level of educational attainment, the proportion of RTOG trial participants mirrored the proportion in the census data. Significant differences were noted only in the youngest category of African-American men, where the RTOG accrues more in the lower educational categories and fewer with college experience. For African-American women, we found a similar pattern in every age group and at each level of educational attainment. As with men, RTOG trials accrued a considerably larger proportion of younger, less educated African-American women than the census reported. Using SEER for comparison, the RTOG enrolled proportionately more African-American men to trials all cancer sites combined, and for prostate and head and neck cancer. In head and neck trials, the RTOG enrolled nearly twice as many African-American men than would be predicted by SEER data. In lung cancer trials, RTOG underrepresented African-American men significantly; however, there was no difference for brain cancer trials. There were

  20. Quantitative Shear Wave Velocity Measurement on Acoustic Radiation Force Impulse Elastography for Differential Diagnosis between Benign and Malignant Thyroid Nodules: A Meta-analysis.

    Science.gov (United States)

    Liu, Bo-Ji; Li, Dan-Dan; Xu, Hui-Xiong; Guo, Le-Hang; Zhang, Yi-Feng; Xu, Jun-Mei; Liu, Chang; Liu, Lin-Na; Li, Xiao-Long; Xu, Xiao-Hong; Qu, Shen; Xing, Mingzhao

    2015-12-01

    The aim of this study was to evaluate the diagnostic performance of quantitative shear wave velocity (SWV) measurement on acoustic radiation force impulse (ARFI) elastography for differentiation between benign and malignant thyroid nodules using meta-analysis. The databases of PubMed and the Web of Science were searched. Studies published in English on assessment of the sensitivity and specificity of ARFI elastography for the differentiation of thyroid nodules were collected. The quantitative measurement of ARFI elastography was evaluated by SWV (m/s). Meta-Disc Version 1.4 software was used to describe and calculate the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio and summary receiver operating characteristic curves. We analyzed a total of 13 studies, which included 1,854 thyroid nodules (including 1,339 benign nodules and 515 malignant nodules) from 1,641 patients. The summary sensitivity and specificity for differential diagnosis between benign and malignant thyroid nodules by SWV were 0.81 (95% confidence interval [CI]: 0.77-0.84) and 0.84 (95% CI: 0.81-0.86), respectively. The pooled positive and negative likelihood ratios were 5.21 (95% CI: 3.56-7.62) and 0.23 (95% CI: 0.17-0.32), respectively. The pooled diagnostic odds ratio was 27.53 (95% CI: 14.58-52.01), and the area under the summary receiver operating characteristic curve was 0.91 (Q* = 0.84). In conclusion, SWV measurement on ARFI elastography has high sensitivity and specificity for differential diagnosis between benign and malignant thyroid nodules and can be used in combination with conventional ultrasound. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  1. Phase II Radiation therapy oncology group trial of weekly paclitaxel and conventional external beam radiation therapy for supratentorial glioblastoma multiforme

    International Nuclear Information System (INIS)

    Langer, Corey J.; Ruffer, James; Rhodes, Harker; Paulus, Rebecca; Murray, Kevin; Movsas, Benjamin; Curran, Walter

    2001-01-01

    Purpose: Fractionated external beam radiotherapy (EBRT) ± carmustine (BCNU) is the standard of care for patients with glioblastoma multiforme (GBM), but survival results remain poor. Preclinical studies indicate synergy between RT and paclitaxel (TAX) in astrocytoma cell lines. Phase I studies in GBM have demonstrated a maximum tolerated dose for TAX of 225 mg/m 2 /3 h/week x 6, during EBRT, with no exacerbation of typical RT-induced toxicities. The Radiation Therapy Oncology Group (RTOG) therefore mounted a Phase II study to determine the feasibility and efficacy of conventional EBRT and concurrent weekly TAX at its MTD. Patients and Methods: Sixty-two patients with histologic diagnosis of GBM were enrolled from 8/16/96 through 3/21/97 in a multi-institutional Phase II trial of EBRT and TAX 225 mg/m 2 /3 h (1-3 h before EBRT), administered the first treatment day of each RT week. Total EBRT dose was 60 Gy (200 cGy/fraction), 5 days per week. A smaller treatment field, to include gross disease plus a margin only, was used after 46 Gy. Results: Sixty-one patients (98%) were evaluable. Median age was 55 years (range, 28-78). Seventy-four percent were ≥50 years. Recursive partitioning analysis (RPA) Classes III, IV, V, VI included 10 (17%), 21 (34%), 25 (41%), and 5 (8%) patients, respectively. Gross total resection was performed in only 16%. There was no Grade 3 or 4 neutropenia or thrombocytopenia. Hypersensitivity reactions precluding further use of TAX occurred in 4 patients. There were 2 instances of late neurotoxicity (4% Grade 3 or 4). Ninety-one percent of patients received treatment per protocol. Seventy-seven percent completed prescribed treatment (6 weeks). Of 35 patients with measurable disease, CR/PR was observed in 23%, MR in 17%, and SD in 43%. Seventeen percent demonstrated progression at first follow-up. Median potential follow-up time is 20 months. Median survival is 9.7 months, with median survivals for RPA classes III, IV, V, and VI of 16.3, 10

  2. Analysis of the health of a group exposed to low doses of ionizing radiation

    International Nuclear Information System (INIS)

    Diaz Ledesma, F.; Crespo, H.

    1997-01-01

    In order to evaluate the effects of exposure to low radiation doses, the health status of professional staff exposed to ionizing radiation is investigated. Based on archived material of medical and radiation exposure records taken over a time span of 13 years, a variety of medical parameters are explored. Findings of surveys made are given. (author)

  3. Reliability and accuracy assessment of radiation therapy oncology group-endorsed guidelines for brachial plexus contouring

    Energy Technology Data Exchange (ETDEWEB)

    Velde, Joris van de [Ghent University, Department of Anatomy, Ghent (Belgium); Ghent University, Department of Radiotherapy, Ghent (Belgium); Vercauteren, Tom; Gersem, Werner de; Vandecasteele, Katrien; Vuye, Philippe; Vanpachtenbeke, Frank; Neve, Wilfried de [Ghent University, Department of Radiotherapy, Ghent (Belgium); Wouters, Johan; Herde, Katharina d' ; Kerckaert, Ingrid; Hoof, Tom van [Ghent University, Department of Anatomy, Ghent (Belgium)

    2014-07-15

    The goal of this work was to validate the Radiation Therapy Oncology Group (RTOG)-endorsed guidelines for brachial plexus (BP) contouring by determining the intra- and interobserver agreement. Accuracy of the delineation process was determined using anatomically validated imaging datasets as a gold standard. Five observers delineated the right BP on three cadaver computed tomography (CT) datasets. To assess intraobserver variation, every observer repeated each delineation three times with a time interval of 2 weeks. The BP contours were divided into four regions for detailed analysis. Inter- and intraobserver variation was verified using the Computerized Environment for Radiation Research (CERR) software. Accuracy was measured using anatomically validated fused CT-magnetic resonance imaging (MRI) datasets by measuring the BP inclusion of the delineations. The overall kappa (κ) values were rather low (mean interobserver overall κ: 0.29, mean intraobserver overall κ: 0.45), indicating poor inter- and intraobserver reliability. In general, the κ coefficient decreased gradually from the medial to lateral BP regions. The total agreement volume (TAV) was much smaller than the union volume (UV) for all delineations, resulting in a low Jaccard index (JI; interobserver agreement 0-0.124; intraobserver agreement 0.004-0.636). The overall accuracy was poor, with an average total BP inclusion of 38 %. Inclusions were insufficient for the most lateral regions (region 3: 21.5 %; region 4: 12.6 %). The inter- and intraobserver reliability of the RTOG-endorsed BP contouring guidelines was poor. BP inclusion worsened from the medial to lateral regions. Accuracy assessment of the contours showed an average BP inclusion of 38 %. For the first time, this was assessed using the original anatomically validated BP volume. The RTOG-endorsed BP guidelines have insufficient accuracy and reliability, especially for the lateral head-and-neck regions. (orig.) [German] Ziel der Studie war

  4. External evaluation of the Radiation Therapy Oncology Group brachial plexus contouring protocol: several issues identified

    International Nuclear Information System (INIS)

    Min, Myo; Carruthers, Scott; Zanchetta, Lydia; Roos, Daniel; Keating, Elly; Shakeshaft, John; Baxi, Siddhartha; Penniment, Michael; Wong, Karen

    2014-01-01

    The aims of the study were to evaluate interobserver variability in contouring the brachial plexus (BP) using the Radiation Therapy Oncology Group (RTOG)-approved protocol and to analyse BP dosimetries. Seven outliners independently contoured the BPs of 15 consecutive patients. Interobserver variability was reviewed qualitatively (visually by using planning axial computed-tomography images and anteroposterior digitally reconstructed radiographs) and quantitatively (by volumetric and statistical analyses). Dose–volume histograms of BPs were calculated and compared. We found significant interobserver variability among outliners in both qualitative and quantitative analyses. These were most pronounced for the T1 nerve roots on visual inspection and for the BP volume on statistical analysis. The BP volumes were smaller than those described in the RTOG atlas paper, with a mean volume of 20.8cc (range 11–40.7 cc) compared with 33±4cc (25.1–39.4cc). The average values of mean dose, maximum dose, V60Gy, V66Gy and V70Gy for patients treated with conventional radiotherapy and IMRT were 42.2Gy versus 44.8Gy, 64.5Gy versus 68.5Gy, 6.1% versus 7.6%, 2.9% versus 2.4% and 0.6% versus 0.3%, respectively. This is the first independent external evaluation of the published protocol. We have identified several issues, including significant interobserver variation. Although radiation oncologists should contour BPs to avoid dose dumping, especially when using IMRT, the RTOG atlas should be used with caution. Because BPs are largely radiologically occult on CT, we propose the term brachial-plexus regions (BPRs) to represent regions where BPs are likely to be present. Consequently, BPRs should in principle be contoured generously.

  5. Design of gamma radiation equipment for studying a bubbling gas fluidized bed. Determination of a radial void fraction profile and bubble velocities in a 0.40 m column

    Energy Technology Data Exchange (ETDEWEB)

    Hoogeveen, M O [Technische Univ. Delft (Netherlands). Lab. voor Fysische Technologie

    1993-12-01

    In this work the possibility of the use of gamma radiation in investigating bubbles in a large three dimensional gas-fluidised bed was examined. A measuring system was designed based upon the absorption of gamma radiation. As high energy (>100 keV) gamma radiation penetrates deeply into matter, it can be used to scan through a gas-solid fluidised bed. The attenuation of a beam of mono-energetic photons is related to the amount of solid particles in the path of the beam. With the gamma absorption technique two parameters can be determined: The void fraction and the bubble velocity. With one narrow beam of gamma radiation a chordal void fraction can be measured in the homogeneous part of the bed. An optimalisation procedure for the void fraction determination led to the choice of Cs-137 as radiation source. This optimalisation procedure concerned minimizing of the standard deviation in the determined chordal void fraction as a function of the energy of gamma radiation. With two narrow parallel beams placed at a distance of 12 cm above each other a bubble velocity can be obtained. A cross-correlation between the two detector responses gives the time shift between the two responses. The system was designed for velocity measurements in the non-homogeneous part of the column. A simulation of the two beam measurement method for an air fluidized bed, 0.40 m in diameter, of polystyrene particles led to the choice of 100 mCi for the source strength for each of the two Cs-137 sources. For a 100 mCi Cs-137 source a shielding of 8 cm of lead is necessary to comply with safety regulations, concerning the use of radioactive materials. A source holder was designed, containing two encapsulated 100 mCi Cs-137 sources, in accordance with the regulations in the licence of the Delft University of Technology for the use of encapsulated sources. (orig.).

  6. Design of gamma radiation equipment for studying a bubbling gas fluidized bed. Determination of a radial void fraction profile and bubble velocities in a 0.40 m column

    International Nuclear Information System (INIS)

    Hoogeveen, M.O.

    1993-12-01

    In this work the possibility of the use of gamma radiation in investigating bubbles in a large three dimensional gas-fluidised bed was examined. A measuring system was designed based upon the absorption of gamma radiation. As high energy (>100 keV) gamma radiation penetrates deeply into matter, it can be used to scan through a gas-solid fluidised bed. The attenuation of a beam of mono-energetic photons is related to the amount of solid particles in the path of the beam. With the gamma absorption technique two parameters can be determined: The void fraction and the bubble velocity. With one narrow beam of gamma radiation a chordal void fraction can be measured in the homogeneous part of the bed. An optimalisation procedure for the void fraction determination led to the choice of Cs-137 as radiation source. This optimalisation procedure concerned minimizing of the standard deviation in the determined chordal void fraction as a function of the energy of gamma radiation. With two narrow parallel beams placed at a distance of 12 cm above each other a bubble velocity can be obtained. A cross-correlation between the two detector responses gives the time shift between the two responses. The system was designed for velocity measurements in the non-homogeneous part of the column. A simulation of the two beam measurement method for an air fluidized bed, 0.40 m in diameter, of polystyrene particles led to the choice of 100 mCi for the source strength for each of the two Cs-137 sources. For a 100 mCi Cs-137 source a shielding of 8 cm of lead is necessary to comply with safety regulations, concerning the use of radioactive materials. A source holder was designed, containing two encapsulated 100 mCi Cs-137 sources, in accordance with the regulations in the licence of the Delft University of Technology for the use of encapsulated sources. (orig.)

  7. Radiation

    International Nuclear Information System (INIS)

    2013-01-01

    The chapter one presents the composition of matter and atomic theory; matter structure; transitions; origin of radiation; radioactivity; nuclear radiation; interactions in decay processes; radiation produced by the interaction of radiation with matter

  8. Interagency task force on the health effects of ionizing radiation: report of the work group on care and benefits

    International Nuclear Information System (INIS)

    1979-06-01

    The report examines existing systems for providing care and benefits to persons who may have been injured by radiation exposure and recommends additional guidelines for handling radiation-related claims. The benefits systems examined are Veterans' benefits, Federal Employees Compensation Act, Longshoremen's and Harbor Workers' Compensation Act, State Workers' Compensation programs, Government and private 'back-up' program, Social Security Disability Insurance (Medicare), Supplemental Security Income (Medicaid), private health insurance, government hospitals, and remedies available under the judicial system. The report recommends that the Federal Government develop guidelines to determine the likelihood of a causal relationship between a person's illness and his exposure to radiation; that Federal compensation programs and State programs develop criteria for deciding radiation exposure claims, based on those guidelines; that a national registry of radiation workers be established to maintain individual radiation exposure records; and that the Federal Government annually compile compensation claims based on radiation exposure. Appendixes list those groups of people most likely to be exposed to radiation, and the benefits available under the various compensation programs listed above

  9. Pulsar velocity observations: Correlations, interpretations, and discussion

    International Nuclear Information System (INIS)

    Helfand, D.J.; Tademaru, E.

    1977-01-01

    From an examination of the current sample of 12 pulsars with measured proper motions and the z-distribution of the much larger group of over 80 sources with measured period derivatives, we develop a self-consistent picture of pulsar evolution. The apparent tendency of pulsars to move parallel to the galactic plane is explained as the result of various selection effects. A method for calculating the unmeasurable radial velocity of a pulsar is presented; it is shown that the total space velocities thus obtained are consistent with the assumption of an extreme Population I origin for pulsars which subsequently move away from the plane with a large range of velocities. The time scale for pulsar magnetic field decay is derived from dynamical considerations. A strong correlation of the original pulsar field strength with the magnitude of pulsar velocity is discussed. This results in the division of pulsars into two classes: Class A sources characterized by low space velocities, a small scale height, and low values of P 0 P 0 ; and Class B sources with a large range of velocities (up to 1000 km s -1 ), a much greater scale height, and larger values of initial field strength. It is postulated that Class A sources originate in tight binaries where their impulse acceleration at birth is insufficient to remove them from the system, while the Class B sources arise from single stars or loosely bound binaries and are accelerated to high velocities by their asymmetric radiation force. The evolutionary picture which is developed is shown to be consistent with a number of constraints imposed by supernova rates, the relative frequency of massive binaries and Class A sources, theoretical field-decay times, and the overall pulsar galactic distribution

  10. The management of respiratory motion in radiation oncology report of AAPM Task Group 76

    International Nuclear Information System (INIS)

    Keall, Paul J.; Mageras, Gig S.; Balter, James M.

    2006-01-01

    This document is the report of a task group of the AAPM and has been prepared primarily to advise medical physicists involved in the external-beam radiation therapy of patients with thoracic, abdominal, and pelvic tumors affected by respiratory motion. This report describes the magnitude of respiratory motion, discusses radiotherapy specific problems caused by respiratory motion, explains techniques that explicitly manage respiratory motion during radiotherapy and gives recommendations in the application of these techniques for patient care, including quality assurance (QA) guidelines for these devices and their use with conformal and intensity modulated radiotherapy. The technologies covered by this report are motion-encompassing methods, respiratory gated techniques, breath-hold techniques, forced shallow-breathing methods, and respiration-synchronized techniques. The main outcome of this report is a clinical process guide for managing respiratory motion. Included in this guide is the recommendation that tumor motion should be measured (when possible) for each patient for whom respiratory motion is a concern. If target motion is greater than 5 mm, a method of respiratory motion management is available, and if the patient can tolerate the procedure, respiratory motion management technology is appropriate. Respiratory motion management is also appropriate when the procedure will increase normal tissue sparing. Respiratory motion management involves further resources, education and the development of and adherence to QA procedures

  11. Does Quality of Radiation Therapy Predict Outcomes of Multicenter Cooperative Group Trials? A Literature Review

    Energy Technology Data Exchange (ETDEWEB)

    Fairchild, Alysa, E-mail: alysa.fairchild@albertahealthservices.ca [Department of Radiation Oncology, Cross Cancer Institute, Edmonton, Alberta (Canada); Straube, William [Advanced Technology Consortium, Imaged-Guided Therapy QA Center, St. Louis, Missouri (United States); Laurie, Fran [Quality Assurance Review Center, Lincoln, Rhode Island (United States); Followill, David [Radiological Physics Center, University of Texas MD Anderson Cancer Centre, Houston, Texas (United States)

    2013-10-01

    Central review of radiation therapy (RT) delivery within multicenter clinical trials was initiated in the early 1970s in the United States. Early quality assurance publications often focused on metrics related to process, logistics, and timing. Our objective was to review the available evidence supporting correlation of RT quality with clinical outcomes within cooperative group trials. A MEDLINE search was performed to identify multicenter studies that described central subjective assessment of RT protocol compliance (quality). Data abstracted included method of central review, definition of deviations, and clinical outcomes. Seventeen multicenter studies (1980-2012) were identified, plus one Patterns of Care Study. Disease sites were hematologic, head and neck, lung, breast, and pancreas. Between 0 and 97% of treatment plans received an overall grade of acceptable. In 7 trials, failure rates were significantly higher after inadequate versus adequate RT. Five of 9 and 2 of 5 trials reported significantly worse overall and progression-free survival after poor-quality RT, respectively. One reported a significant correlation, and 2 reported nonsignificant trends toward increased toxicity with noncompliant RT. Although more data are required, protocol-compliant RT may decrease failure rates and increase overall survival and likely contributes to the ability of collected data to answer the central trial question.

  12. Chemical reactions on platinum-group metal surfaces studied by synchrotron-radiation-based spectroscopy

    International Nuclear Information System (INIS)

    Kondoh, Hiroshi; Nakai, Ikuyo; Nagasaka, Masanari; Amemiya, Kenta; Ohta, Toshiaki

    2009-01-01

    A new version of synchrotron-radiation-based x-ray spectroscopy, wave-length-dispersive near-edge x-ray absorption fine structure (dispersive-NEXAFS), and fast x-ray photoelectron spectroscopy have been applied to mechanistic studies on several surface catalytic reactions on platinum-group-metal surfaces. In this review, our approach using above techniques to understand the reaction mechanism and actual application studies on three well-known catalytic surface reactions, CO oxidation on Pt(111) and Pd(111), NO reduction on Rh(111), and H 2 O formation on Pt(111), are introduced. Spectroscopic monitoring of the progress of the surface reactions enabled us to detect reaction intermediates and analyze the reaction kinetics quantitatively which provides information on reaction order, rate constant, pre-exponential factor, activation energy and etc. Such quantitative analyses combined with scanning tunneling microscopy and kinetic Monte Carlo simulations revealed significant contribution of the adsorbate configurations and their dynamic changes to the reaction mechanisms of the above fundamental catalytic surface reactions. (author)

  13. Does Quality of Radiation Therapy Predict Outcomes of Multicenter Cooperative Group Trials? A Literature Review

    International Nuclear Information System (INIS)

    Fairchild, Alysa; Straube, William; Laurie, Fran; Followill, David

    2013-01-01

    Central review of radiation therapy (RT) delivery within multicenter clinical trials was initiated in the early 1970s in the United States. Early quality assurance publications often focused on metrics related to process, logistics, and timing. Our objective was to review the available evidence supporting correlation of RT quality with clinical outcomes within cooperative group trials. A MEDLINE search was performed to identify multicenter studies that described central subjective assessment of RT protocol compliance (quality). Data abstracted included method of central review, definition of deviations, and clinical outcomes. Seventeen multicenter studies (1980-2012) were identified, plus one Patterns of Care Study. Disease sites were hematologic, head and neck, lung, breast, and pancreas. Between 0 and 97% of treatment plans received an overall grade of acceptable. In 7 trials, failure rates were significantly higher after inadequate versus adequate RT. Five of 9 and 2 of 5 trials reported significantly worse overall and progression-free survival after poor-quality RT, respectively. One reported a significant correlation, and 2 reported nonsignificant trends toward increased toxicity with noncompliant RT. Although more data are required, protocol-compliant RT may decrease failure rates and increase overall survival and likely contributes to the ability of collected data to answer the central trial question

  14. Organic Crystal Growth Facility (OCGF) and Radiation Monitoring Container Device (RMCD) Groups in

    Science.gov (United States)

    1992-01-01

    The primary payload for Space Shuttle Mission STS-42, launched January 22, 1992, was the International Microgravity Laboratory-1 (IML-1), a pressurized manned Spacelab module. The goal of IML-1 was to explore in depth the complex effects of weightlessness of living organisms and materials processing. Around-the-clock research was performed on the human nervous system's adaptation to low gravity and effects of microgravity on other life forms such as shrimp eggs, lentil seedlings, fruit fly eggs, and bacteria. Materials processing experiments were also conducted, including crystal growth from a variety of substances such as enzymes, mercury iodide, and a virus. The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Featured are activities of the Organic Crystal Growth Facility (OCGF) and Radiation Monitoring Container Device (RMCD) groups in the SL POCC during the IML-1 mission.

  15. IAEA advisory group meeting on dosimetry for high doses employed in industrial radiation processing, Vienna, 17-21 November 1980

    International Nuclear Information System (INIS)

    Chadwick, K.H.

    1981-01-01

    In 1977 the IAEA established a programme on High-Dose Standardization and Intercomparison with the aim of developing a world-wide service for dosimetry assurance in Industrial and Research Radiation Processing Facilities. The complete proceedings of the first Advisory Group meeting held within this programme have recently been published in the IAEA Technical Reports Series (No. 205) under the title ''High-Dose Measurement in Industrial Radiation Processing''. This report of the second Advisory Group meeting provides a brief review of the state of the programme at the present time. (The full proceedings of the meeting will not be published)

  16. Report of the Study Group on Safety of RI and Radiation Uses

    International Nuclear Information System (INIS)

    Yamazaki, Fumio

    1977-01-01

    To grasp the present state of RI and radiation usages, a survey by questionnaire was made on the enterprises using small sealed radiation sources, the enterprises carrying out nondestructive tests with large radiation sources and the medical institutions utilizing RIs and radiation. The results of the study aiming at establishing the reasonable and adequate measures of safety management are described together with the survey results. The items studied are the legal regulations, facilities, education and training of workers, and radioactive waste management. (Mori, K.)

  17. Multidisk neutron velocity selectors

    International Nuclear Information System (INIS)

    Hammouda, B.

    1992-01-01

    Helical multidisk velocity selectors used for neutron scattering applications have been analyzed and tested experimentally. Design and performance considerations are discussed along with simple explanation of the basic concept. A simple progression is used for the inter-disk spacing in the 'Rosta' design. Ray tracing computer investigations are presented in order to assess the 'coverage' (how many absorbing layers are stacked along the path of 'wrong' wavelength neutrons) and the relative number of neutrons absorbed in each disk (and therefore the relative amount of gamma radiation emitted from each disk). We discuss whether a multidisk velocity selector can be operated in the 'reverse' configuration (i.e. the selector is turned by 180 0 around a vertical axis with the rotor spun in the reverse direction). Experimental tests and calibration of a multidisk selector are reported together with evidence that a multidisk selector can be operated in the 'reverse' configuration. (orig.)

  18. Profile of European radiotherapy departments contributing to the EORTC Radiation Oncology Group (ROG) in the 21st century

    NARCIS (Netherlands)

    Budiharto, Tom; Musat, Elena; Poortmans, Philip; Hurkmans, Coen; Monti, Angelo; Bar-Deroma, Raquel; Bernstein, Zvi; van Tienhoven, Geertjan; Collette, Laurence; Duclos, Frédéric; Davis, Bernard; Aird, Edwin

    2008-01-01

    Since 1982, the Radiation Oncology Group of the EORTC (EORTC ROG) has pursued an extensive Quality Assurance (QA) program involving all centres actively participating in its clinical research. The first step is the evaluation of the structure and of the human, technical and organisational resources

  19. Pretreatment quality of life predicts for locoregional control in head and neck cancer patients : A radiation therapy oncology group analysis

    NARCIS (Netherlands)

    Siddiqui, Farzan; Pajak, Thomas F.; Watkins-Bruner, Deborah; Konski, Andre A.; Coyne, James C.; Gwede, Clement K.; Garden, Adam S.; Spencer, Sharon A.; Jones, Christopher; Movsas, Benjamin

    2008-01-01

    Purpose: To analyze the prospectively collected health-related quality-of-life (HRQOL) data from patients enrolled in two Radiation Therapy Oncology Group randomized Phase III head and neck cancer trials (90-03 and 91-11) to assess their value as an independent prognostic factor for locoregional

  20. Questions and Advice to the Swedish Radiation Authority in their Current Work on Radiation Safety from Participants in Focus Group Discussions in the Municipalities of Oesthammar and Oskarshamn

    International Nuclear Information System (INIS)

    Drottz-Sjoeberg, Britt-Marie

    2003-01-01

    In connection to their work on developing a 'general advice document', based on the radiation protection law, the Swedish Radiation Authority (SSI) initiated a process in 2002 that welcomed comments and suggestions from the general public, specifically representatives and interested parties involved in the work related to a Swedish repository for high level nuclear wastes. The authority held a seminar in September, and presented the forthcoming task. The present paper summarises and exemplifies discussions in focus groups in October 2002, when participants from the municipalities of Oskarshamn and Oesthammar met to give their input to the authority's ongoing work. The questions and suggestions emerging from the focus groups are classified into three major areas in this presentation: 1. Issues related specifically to radiation and radioactivity. 2. Issues of comprehension of terminology, measurements, risk, and safety. 3. Issues concerning the information process and the transfer of knowledge. The discussion highlights that issues and comments raised by the public are not constrained to specific knowledge questions, e.g. on radiation or risk, but may relate to legal, strategic and political considerations, as well as the basics of the performed analyses and the related assumptions and evaluations. Ideas for improving public knowledge and for facilitating an exchange of information are outlined below

  1. Fast Neutron Radiotherapy for Locally Advanced Prostate Cancer: Final Report of a Radiation Therapy Oncology Group Randomized Clinical Trial

    Energy Technology Data Exchange (ETDEWEB)

    Laramore, G. E.; Krall, J. M.; Thomas, F. J.; Russell, K. J.; Maor, M. H.; Hendrickson, F. R.; Martz, K. L.; Griffin, T. W.; Davis, L. W.

    1993-01-01

    Between June 1977 and April 1983 the Radiation Therapy Oncology Group (RTOG) sponsored a Phase III randomized trial investigating the use of fast neutron radiotherapy for patients with locally advanced (Stages C and D1) adenocarcinoma of the prostate gland. Patients were randomized to receive either conventional photon radiation or fast neutron radiation used in a mixed-beam (neutron/photon) treatment schedule. A total of 91 analyzable patients were entered into the study, and the two patient groups were balanced with respect to the major prognostic variables. Actuarial curves are presented for local/regional control and "overall" survival. Ten-year results for clinically assessed local control are 70% for the mixed-beam group versus 58% for the photon group (p = 0.03) and for survival are 46% for the mixed-beam group versus 29% for the photon group (p = 0.04). This study suggests that a regional method of treatment can influence both local tumor control and survival in patients with locally advanced adenocarcinoma of the prostate gland.

  2. Revision and Microtomography of the Pheidole knowlesi Group, an Endemic Ant Radiation in Fiji (Hymenoptera, Formicidae, Myrmicinae)Myrmicinae).

    Science.gov (United States)

    Fischer, Georg; Sarnat, Eli M; Economo, Evan P

    2016-01-01

    The Fijian islands, a remote archipelago in the southwestern Pacific, are home to a number of spectacular endemic radiations of plants and animals. Unlike most Pacific archipelagos, these evolutionary radiations extend to social insects, including ants. One of the most dramatic examples of ant radiation in Fiji has occurred in the hyperdiverse genus Pheidole. Most of the 17 native Fijian Pheidole belong to one of two species groups that descended from a single colonization, yet have evolved dramatically contrasting morphologies: the spinescent P. roosevelti species group, and the more morphologically conservative P. knowlesi species group. Here we revise the knowlesi group, in light of recent phylogenetic results, and enhanced with modern methods of X-ray microtomography. We recognize six species belonging to this group, including two of which we describe as new: Pheidole caldwelli Mann, Pheidole kava sp. n., Pheidole knowlesi Mann, P. ululevu sp. n., P. vatu Mann, and P. wilsoni Mann. Detailed measurements and descriptions, identification keys, and high-resolution images for queens, major and minor workers are provided. In addition, we include highly detailed 3D surface reconstructions for all available castes.

  3. Radial velocity asymmetries from jets with variable velocity profiles

    International Nuclear Information System (INIS)

    Cerqueira, A. H.; Vasconcelos, M. J.; Velazquez, P. F.; Raga, A. C.; De Colle, F.

    2006-01-01

    We have computed a set of 3-D numerical simulations of radiatively cooling jets including variabilities in both the ejection direction (precession) and the jet velocity (intermittence), using the Yguazu-a code. In order to investigate the effects of jet rotation on the shape of the line profiles, we also introduce an initial toroidal rotation velocity profile. Since the Yguazu-a code includes an atomic/ionic network, we are able to compute the emission coefficients for several emission lines, and we generate line profiles for the Hα, [O I]λ6300, [S II]λ6716 and [N II]λ6548 lines. Using initial parameters that are suitable for the DG Tau microjet, we show that the computed radial velocity shift for the medium-velocity component of the line profile as a function of distance from the jet axis is strikingly similar for rotating and non-rotating jet models

  4. Degree and therapy of acute radiation syndromes. Introduction of a suggestion on acute radiation sickness therapy made by strategic national stockpile radiation working group of USA. part 2

    International Nuclear Information System (INIS)

    Min Rui; Pan Zhen; Li Yu

    2005-01-01

    Recommendations based on radiation dose and physiologic response are made for treatment of the hematopoietic syndrome. Therapy includes treatment with hematopoietic cytokines, blood transfusion, and stem-cell transplantation in selected cases. Additional medical management based on the evolution of clinical signs and symptoms includes the use of antimicrobial agents (quinolones, antiviral therapy, and antifungal agents), antiemetic agents, and analgesic agents. Because of the strong psychological impact of a possible radiation exposure, psychosocial support will be required for those exposed, regardless of the dose, as well as for family and friends. Treatment of pregnant women must account for risk to the fetus. For terrorist or accidental events involving exposure to radioiodines, prophylaxis against malignant disease of the thyroid is also recommended, particularly for children and adolescents. (authors)

  5. Modern Radiation Therapy for Nodal Non-Hodgkin Lymphoma—Target Definition and Dose Guidelines From the International Lymphoma Radiation Oncology Group

    DEFF Research Database (Denmark)

    Illidge, Tim; Specht, Lena; Yahalom, Joachim

    2014-01-01

    Radiation therapy (RT) is the most effective single modality for local control of non-Hodgkin lymphoma (NHL) and is an important component of therapy for many patients. Many of the historic concepts of dose and volume have recently been challenged by the advent of modern imaging and RT planning...... tools. The International Lymphoma Radiation Oncology Group (ILROG) has developed these guidelines after multinational meetings and analysis of available evidence. The guidelines represent an agreed consensus view of the ILROG steering committee on the use of RT in NHL in the modern era. The roles...... of reduced volume and reduced doses are addressed, integrating modern imaging with 3-dimensional planning and advanced techniques of RT delivery. In the modern era, in which combined-modality treatment with systemic therapy is appropriate, the previously applied extended-field and involved-field RT...

  6. Evaluation of the prevalence of burnout and psychological morbidity among radiation oncologist members of the Kyoto Radiation Oncology Study Group (KROSG)

    International Nuclear Information System (INIS)

    Mampuya, Wambaka Ange; Matsuo, Yukinori; Nakamura, Akira; Hiraoka, Masahiro

    2017-01-01

    This study aimed to evaluate the self-reported prevalence of burnout and psychological morbidity among radiation oncologists members of the Kyoto Radiation Oncology Study Group (KROSG) and to identify factors contributing to burnout. We mailed an anonymous survey to 125 radiation oncologists members of the KROSG. The survey included; the demographic data, the Maslach Burnout Inventory – Human Services Survey (MBI-HSS) and the 12-item General Health Questionnaire (GHQ-12). There were 87 responses out of 125 eligible respondents (69.6% response rate). In terms of burnout, three participants (3.4%) fulfilled the MBI-HSS criteria of having simultaneously high emotional exhaustion (EE), high depersonalization (DP) and low sense of personal accomplishment (PA). Eighteen (20.6%) reported a high score for either EE or DP meeting the alternative criteria for burnout with three of these simultaneously having high EE and high DP. The prevalence of psychological morbidity estimated using GHQ-12 was 32%. A high level of EE and low level of PA significantly correlated with high level of psychological morbidity with P < 0.001 and <0.01 respectively. Having palliative care activities other than radiotherapy and number of patients treated per year were the only factors associated with burnout. This is the first study investigating the prevalence of burnout and psychological morbidity among radiation oncologists in Japan. Compared with other studies involving radiation oncologists, the prevalence of low personal accomplishment was particularly high in the present study. The prevalence of psychological morbidity was almost the double that of the Japanese general population and was significantly associated with low PA and high EE.

  7. Measurement of the natural radiation environment and its dependence on various parameters in Austria and assessment of the natural external and internal radiation dose of various population groups

    International Nuclear Information System (INIS)

    Pohl, E.

    1978-06-01

    The natural mean values of natural radionuclides in the air and external gamma radiation were determined from measurements carried out in various parts of Austria and the mean values were used as a basis for the determination of body and organ doses. Moreover frequency distributions of several specific organ doses within various population groups were investigated. Measurements of natural air activity were carried out indoors and outdoors as well as gamma radiation at the following sites - Salzburg Town, Badgastein, Gastein Valley and Mallnitz and several other places at a line crossing the Alps from South to North (Corinthia, Schwarzach, Forstau, Hallein, Kuchl, Grodig and Voggenberg - Bergheim) and in 15 different mines in the Counties of Salzburg and Upper Austria. The methods of calculation of the radiation burden due to inhalation is published in the Proceedings of the Symposium on Biological and Environmental Effects of Low Level Radiation, IAEA, Chicago 1976, Vol. II pages 305-315. It can be concluded from the work that great local differences of some components occur even within relatively small areas. The radioactivity in the air shows great temporal differences at one and the same site. In addition radiation doses had to be calculated separately for various organs and tissues due to the inhomogeneous distribution of doses within the body. Also the estimation had to be made for a variety of individuals depending on sex, age, weight and various physiological states of activity. The highest doses to tissues from inhalation of natural radioactivity are the basal cells of the sigmental epithelium and subsigmental bronchi 4th - 9th generation in the lung model of Weibel. 46% of the population investigated received more than 0.5 rem per year, 25% more than 1.5 rem per year and 1.3% more than 3 rem per year. The different air activities in the living and working rooms are due to differences in the building materials and in the construction of houses

  8. Mini-Proceedings, 18th Meeting of the Working Group on Radiative Corrections and MC Generators for Low Energies

    CERN Document Server

    Masjuan, P; Venanzoni, G

    2016-01-01

    The mini-proceedings of the 18$^{\\mathrm{th}}$ Meeting of the "Working Group on Radiative Corrections and MonteCarlo Generators for Low Energies" held in Frascati, 19$^{\\mathrm{th}}$ - 20$^{\\mathrm{st}}$ May, are presented. These meetings, started in 2006, have as aim to bring together experimentalists and theoreticians working in the fields of meson transition form factors, hadronic contributions to the anomalous magnetic moment of the leptons, and the effective fine structure constant. The development of MonteCarlo generators and Radiative Corrections for precision $e^+e^-$ and $\\tau$-lepton physics are also covered, with emphasis on meson production. At this workshop, a documentary entitled {\\it Bruno Touschek with AdA in Orsay} commemorating the first observation of electron-positron collisions in a laboratory was also presented. With this edition, the working group reaches 10 years of continuous activities.

  9. Quality control of sickness rate registration of the Chernobil accident liquidators into a different radiation dose groups

    International Nuclear Information System (INIS)

    Biryukov, A.P.; Ivanov, V.K.; Bolokhonenkova, M.A.; Kochergina, E.V.; Kruglova, Z.G.; Zelenskaya, N.S.; Ukraintsev, V.F.

    2005-01-01

    Effect of the dose factor on the quality of registration of the liquidator health state is studied. It is shown that the efficiency of prophylactic system and monitoring intensity in the different dose groups are equal, are determined by general legislative acts on the all territory of the Russian Federation and do not influence the results of carrying out the radiation-epidemic analysis [ru

  10. The impact of radiation dose and fractionation on the risk factor of radiation pneumonitis on four radiation therapy oncology group (RTOG) lung cancer trials

    International Nuclear Information System (INIS)

    Roach, Mack; Pajak, Thomas F; Byhardt, Roger; Graham, Mary L; Asbell, Sucha O; Russell, Anthony H; Fu, Karen K; Urtasun, Raul C; Herskovic, Arnold M; Cox, James D

    1997-01-01

    Purpose/Objective: To assess the relationship between total dose of radiation delivered, the fractionation scheme used, age, and Karnofsky Performance Status (KPS) on the risk of moderate to severe (≥ Grade 2) radiation pneumonitis in patients treated with radiotherapy alone for lung cancer on four RTOG Trials. Materials and Methods: Between February of 1984 and April of 1989, 1701 patients with clinically localized (I-IIIb) lung cancer were entered on clinical trials employing radiotherapy alone. Twelve hundred and forty-seven patients were entered on RTOG 8311 or 8407 (phase I/II trials) and 454 patients were entered on RTOG 8321 or 8403 (phase III trials). RTOG 8403 and 8321 patients received once-a-day irradiation to 60 Gy. Patients treated on RTOG 8407 were treated with a concomitant boost technique in a non-randomized fashion to 64.8, 69.6, 74.4 or 79.2 Gy. Patients treated on RTOG 8407 were treated with a concomitant boost technique in a non-randomized fashion to 63 Gy or 70.2 Gy. All patients were assessed for the incidence of Grade 2-5, radiation pneumonitis. One hundred and seven (6%) of patients were either ineligible or canceled (n=60), or were excluded because of incomplete data (n=47). The factors evaluated included total dose of radiation, the fractionation scheme, age and pre-treatment KPS. Patients treated to doses ≥ 72 Gy were considered to have received high doses (72.0 - 81.6 Gy), while the remaining patients treated to doses < 72 Gy (57.6 - 71.9 Gy) were considered to have received standard dose radiation. For the this analysis, information regarding field size and baseline pulmonary function was not available. Results: Age, sex, stage distribution, and the percentage of patients with a KPS ≥90 were similar among the patients treated on these four studies. Patients receiving hyperfractionated radiotherapy to doses ≥ 72 Gy experienced a higher incidence of radiation pneumonitis ≥ Grade 2, than patients treated with standard doses < 72

  11. Ionizing radiation target groups of band 3 inserted into egg lecithin liposomes as determined by Raman spectroscopy

    International Nuclear Information System (INIS)

    Verma, S.P.; Sonwalkar, N.

    1993-01-01

    The purified integral membrane protein, band 3, from human erythrocytes was inserted into egg lecithin liposomes. The insertion of band 3 was determined from thermal transition data from the analysis of the C-H stretching region bands recorded at temperatures from 25 to -22 o C. Raman spectra show that band 3 considerably broadens and lowers the thermal transition of egg lecithin liposomes, suggesting the insertion of band 3. The band 3-inserted liposomes were irradiated with gamma-rays (40 Gy) and the radiation target groups were determined by the analysis of the structural sensitive Raman bands in the 1600-1700 cm -1 (amide I), 1200-1300 cm -1 (amide III) and 550-1030 cm -1 (side chain amino groups) regions. The radiation-sensitive groups as identified from Raman spectra in the region 550-1030 cm -1 are tyrosines and cysteines. The radiation-induced changes in the secondary structure were determined from amide I and III bands. Quantitative estimation using the curve fitting method shows that ban 3 contains 44% total helix, 48% beta strand and 8% undefined plus turns (error + or - 4%). The secondary structure changes to 35% total helix, 42% total beta-strand and 23% turned and undefined upon irradiating band 3 containing liposomes. (Author)

  12. Radiation: Basic life for human

    International Nuclear Information System (INIS)

    Wan Saffiey Wan Abdullah

    2009-01-01

    Basically, radiation is sources for everything in this world. From radiation, many reactions and activities can be done by organisms. The tree can do photosynthesis and at the same time can give oxygen to human and others. In Quran, radiation was mentioned almost 41 times and from that, 12 are preferred to sun, moon, and stars. Radiation can be classified into two groups, mechanical and electromagnetic. Mechanical radiations are produced from vibration process. For example, when we are talking, sound radiation will be produced from vibration of sounds box. The guitar will sounded when we pluck it. Generally, mechanical radiation needs medium for its propagation and the velocity of wave can change and it cannot propagate in vacuum states. Meanwhile, electromagnetic radiations are energy that emitted in wave produced by propagation of electrical charges. This will produce magnetic fields and then if these fields changed, electrical fields will produce. There are two types of radiation in human life, natural radiation and artificially radiation. Radiation can be applied in medical and defend sector. Radiation also can be misuse by some people that want it for other purpose in intention to do something wrong, such as in making bomb and others weapons. In Malaysia, there are one act to control the imports, exports, licensing, transferring and application of ionizing radiation but not for non-ionizing radiation. In future, laser radiations have their own potential to become one of the most important radiations in renewable energy sector, medical and defend.

  13. The report of Task Group 100 of the AAPM: Application of risk analysis methods to radiation therapy quality management

    Energy Technology Data Exchange (ETDEWEB)

    Huq, M. Saiful, E-mail: HUQS@UPMC.EDU [Department of Radiation Oncology, University of Pittsburgh Cancer Institute and UPMC CancerCenter, Pittsburgh, Pennsylvania 15232 (United States); Fraass, Benedick A. [Department of Radiation Oncology, Cedars-Sinai Medical Center, Los Angeles, California 90048 (United States); Dunscombe, Peter B. [Department of Oncology, University of Calgary, Calgary T2N 1N4 (Canada); Gibbons, John P. [Ochsner Health System, New Orleans, Louisiana 70121 (United States); Ibbott, Geoffrey S. [Department of Radiation Physics, UT MD Anderson Cancer Center, Houston, Texas 77030 (United States); Mundt, Arno J. [Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, California 92093-0843 (United States); Mutic, Sasa [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 (United States); Palta, Jatinder R. [Department of Radiation Oncology, Virginia Commonwealth University, P.O. Box 980058, Richmond, Virginia 23298 (United States); Rath, Frank [Department of Engineering Professional Development, University of Wisconsin, Madison, Wisconsin 53706 (United States); Thomadsen, Bruce R. [Department of Medical Physics, University of Wisconsin, Madison, Wisconsin 53705-2275 (United States); Williamson, Jeffrey F. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298-0058 (United States); Yorke, Ellen D. [Department of Medical Physics, Memorial Sloan-Kettering Center, New York, New York 10065 (United States)

    2016-07-15

    The increasing complexity of modern radiation therapy planning and delivery challenges traditional prescriptive quality management (QM) methods, such as many of those included in guidelines published by organizations such as the AAPM, ASTRO, ACR, ESTRO, and IAEA. These prescriptive guidelines have traditionally focused on monitoring all aspects of the functional performance of radiotherapy (RT) equipment by comparing parameters against tolerances set at strict but achievable values. Many errors that occur in radiation oncology are not due to failures in devices and software; rather they are failures in workflow and process. A systematic understanding of the likelihood and clinical impact of possible failures throughout a course of radiotherapy is needed to direct limit QM resources efficiently to produce maximum safety and quality of patient care. Task Group 100 of the AAPM has taken a broad view of these issues and has developed a framework for designing QM activities, based on estimates of the probability of identified failures and their clinical outcome through the RT planning and delivery process. The Task Group has chosen a specific radiotherapy process required for “intensity modulated radiation therapy (IMRT)” as a case study. The goal of this work is to apply modern risk-based analysis techniques to this complex RT process in order to demonstrate to the RT community that such techniques may help identify more effective and efficient ways to enhance the safety and quality of our treatment processes. The task group generated by consensus an example quality management program strategy for the IMRT process performed at the institution of one of the authors. This report describes the methodology and nomenclature developed, presents the process maps, FMEAs, fault trees, and QM programs developed, and makes suggestions on how this information could be used in the clinic. The development and implementation of risk-assessment techniques will make radiation

  14. The report of Task Group 100 of the AAPM: Application of risk analysis methods to radiation therapy quality management

    International Nuclear Information System (INIS)

    Huq, M. Saiful; Fraass, Benedick A.; Dunscombe, Peter B.; Gibbons, John P.; Ibbott, Geoffrey S.; Mundt, Arno J.; Mutic, Sasa; Palta, Jatinder R.; Rath, Frank; Thomadsen, Bruce R.; Williamson, Jeffrey F.; Yorke, Ellen D.

    2016-01-01

    The increasing complexity of modern radiation therapy planning and delivery challenges traditional prescriptive quality management (QM) methods, such as many of those included in guidelines published by organizations such as the AAPM, ASTRO, ACR, ESTRO, and IAEA. These prescriptive guidelines have traditionally focused on monitoring all aspects of the functional performance of radiotherapy (RT) equipment by comparing parameters against tolerances set at strict but achievable values. Many errors that occur in radiation oncology are not due to failures in devices and software; rather they are failures in workflow and process. A systematic understanding of the likelihood and clinical impact of possible failures throughout a course of radiotherapy is needed to direct limit QM resources efficiently to produce maximum safety and quality of patient care. Task Group 100 of the AAPM has taken a broad view of these issues and has developed a framework for designing QM activities, based on estimates of the probability of identified failures and their clinical outcome through the RT planning and delivery process. The Task Group has chosen a specific radiotherapy process required for “intensity modulated radiation therapy (IMRT)” as a case study. The goal of this work is to apply modern risk-based analysis techniques to this complex RT process in order to demonstrate to the RT community that such techniques may help identify more effective and efficient ways to enhance the safety and quality of our treatment processes. The task group generated by consensus an example quality management program strategy for the IMRT process performed at the institution of one of the authors. This report describes the methodology and nomenclature developed, presents the process maps, FMEAs, fault trees, and QM programs developed, and makes suggestions on how this information could be used in the clinic. The development and implementation of risk-assessment techniques will make radiation

  15. The report of Task Group 100 of the AAPM: Application of risk analysis methods to radiation therapy quality management

    Science.gov (United States)

    Huq, M. Saiful; Fraass, Benedick A.; Dunscombe, Peter B.; Gibbons, John P.; Mundt, Arno J.; Mutic, Sasa; Palta, Jatinder R.; Rath, Frank; Thomadsen, Bruce R.; Williamson, Jeffrey F.; Yorke, Ellen D.

    2016-01-01

    The increasing complexity of modern radiation therapy planning and delivery challenges traditional prescriptive quality management (QM) methods, such as many of those included in guidelines published by organizations such as the AAPM, ASTRO, ACR, ESTRO, and IAEA. These prescriptive guidelines have traditionally focused on monitoring all aspects of the functional performance of radiotherapy (RT) equipment by comparing parameters against tolerances set at strict but achievable values. Many errors that occur in radiation oncology are not due to failures in devices and software; rather they are failures in workflow and process. A systematic understanding of the likelihood and clinical impact of possible failures throughout a course of radiotherapy is needed to direct limit QM resources efficiently to produce maximum safety and quality of patient care. Task Group 100 of the AAPM has taken a broad view of these issues and has developed a framework for designing QM activities, based on estimates of the probability of identified failures and their clinical outcome through the RT planning and delivery process. The Task Group has chosen a specific radiotherapy process required for “intensity modulated radiation therapy (IMRT)” as a case study. The goal of this work is to apply modern risk-based analysis techniques to this complex RT process in order to demonstrate to the RT community that such techniques may help identify more effective and efficient ways to enhance the safety and quality of our treatment processes. The task group generated by consensus an example quality management program strategy for the IMRT process performed at the institution of one of the authors. This report describes the methodology and nomenclature developed, presents the process maps, FMEAs, fault trees, and QM programs developed, and makes suggestions on how this information could be used in the clinic. The development and implementation of risk-assessment techniques will make radiation

  16. UV light-induced survival response in a highly radiation-resistant isolate of the Moraxella-acinetobacter group

    International Nuclear Information System (INIS)

    Keller, L.C.; Thompson, T.L.; Maxcy, R.B.

    1982-01-01

    A highly radiation-resistant member of the Moraxella-Acinetobacter group, isolate 4, obtained from meat, was studied to determine the effect of preexposure to UV radiation on subsequent UV light resistance. Cultures that were preexposed to UV light and incubated for a short time in plate count broth exhibited increased survival of a UV light challenge dose. This response was inhibited in the presence of chloramphenicol. Frequencies of mutation to streptomycin, trimethoprim, and sulfanilamide resistance remained the same after the induction of this survival response and were not altered by treatment with mutagens, with the exception of mutation to streptomycin resistance after γ-irradiation or nitrosoguanidine or methyl methane sulfonate treatment. The results indicated that isolate 4 has a UV light-inducible UV light resistance mechanism which is not associated with increased mutagenesis. The characteristics of the radiation resistance response in this organism are similar to those of certain other common food contaminants. Therefore, considered as part of the total microflora of meat, isolate 4 and the other radiation-resistant Moraxella-Acinetobacter isolates should not pose unique problems in a proposed radappertizaton process

  17. Leukaemia following childhood radiation exposure in the Japanese atomic bomb survivors and in medically exposed groups

    International Nuclear Information System (INIS)

    Little, M. P.

    2008-01-01

    Incidence and mortality risks of radiation-associated leukaemia are surveyed in the Japanese atomic bomb (A-bomb) survivors exposed in early childhood and in utero. Leukaemia incidence and mortality risks are also surveyed in 16 other studies of persons who received appreciable doses of ionizing radiation in the course of treatment in childhood and for whom there is adequate dosimetry and cancer incidence or mortality follow-up. Relative risks tend to be lower in the medical series than in the Japanese A-bomb survivors. The relative risks in the medical studies tend to diminish with increasing average therapy dose. After taking account of cell sterilisation and dose fractionation, the apparent differences between the relative risks for leukaemia in the Japanese A-bomb survivors and in the medical series largely disappear. This suggests that cell sterilisation largely accounts for the discrepancy between the relative risks in the Japanese data and the medical studies. Excess absolute risk has also been assessed in four studies, and there is found to be more variability in this measure than in excess relative risk. In particular, there is a substantial difference between the absolute risk in the Japanese atomic bomb survivor data and those in three other (European) populations. In summary, the relative risks of leukaemia in studies of persons exposed to appreciable doses of ionizing radiation in the course of treatment for a variety of malignant and non-malignant conditions in childhood are generally less than those in the Japanese A-bomb survivor data. The effects of cell sterilisation can largely explain the discrepancy between the Japanese and the medical series. (authors)

  18. Impact of incoherent pumping field and Er3+ ion concentration on group velocity and index of refraction in an Er3+-doped YAG crystal

    International Nuclear Information System (INIS)

    Jafarzadeh, Hossein; Asadpour, Seyyed Hossein; Soleimani, H Rahimpour

    2015-01-01

    The effect of Er 3+ ion concentration and incoherent pumping field on the refractive index and group index in an Er 3+ : YAG crystal is investigated. It is shown that under different concentrations of Er 3+ ion in the crystal, the index of refraction and absorption can be changed and a high index of refraction is accompanied by amplification in the medium. Also, it is shown that with the switching from subluminal to superluminal, or vice versa, light propagation can be obtained by different concentrations of Er 3+ ions in the crystal. (paper)

  19. Towards a new radiation protection system. Report of an expert group

    International Nuclear Information System (INIS)

    2002-01-01

    The regulations and the standards of national and international radiation protection are based on the recommendations published by the International Commission of radiological protection (ICRP). New recommendations, that would replace these ones edited 1990, are actually developed with a foreseen date for 2005 and it is of interest for each country member of Nea to make these recommendations take into account the need of national regulatory authorities. This report is based on a preliminary study of two years, and proposes specific improvements that would make easy the understanding and application of the system and would be considered for the compiling of new ICRP recommendations. (N.C.)

  20. Analysis of toxicity of Milkier cell carcinoma of the skin treated with synchronous carboplatin/etoposide and radiation: a Trans-Tasman Radiation Oncology Group study

    International Nuclear Information System (INIS)

    Poulsen, Michael; Rischin, Danny; Walpole, Evan; Harvey, Jennifer; Macintosh, John; Ainslie, Jill; Hamilton, Chris; Keller, Jacqui B.; Tripcony, Lee B.

    2001-01-01

    Purpose: The acute and late toxicities of synchronous carboplatin, etoposide, and radiation therapy were prospectively assessed in a group of patients with high-risk Milkier cell carcinoma of the skin. Patients and Methods: Forty patients from six different centers throughout Australia were entered into a Phase II study under the auspices of the Trans-Tasman Radiation Oncology Group. The trial was activated in 1996 and continues to accrue. Patients are eligible if they have disease localized to the primary site and nodes and are required to have at least one of the following high-risk features: recurrence after initial therapy, involved nodes, primary size greater than 1 cm, gross residual disease after surgery, or occult primary with nodes. Radiation was delivered to the primary site and nodes to a dose of 50 Gy in 25 fractions over 5 weeks, and synchronous carboplatin (area under curve [Auc] 4.5) and etoposide (80 mg/M 2 i.v.) were given on days 1-3 during weeks 1, 4, 7, and 10. The median age of the group was 67 years (43-78). Results: The median duration of follow-up was 22 months (2-45). There were no treatment-related deaths. Grade 3 or 4 skin toxicity occurred in 63% of patients (95% CI 48, 78). The most serious acute effect was on neutrophils with Grade 3 or 4 (neutrophils 9 /L), occurring in 60% (95% CI 45, 75) of cases. Complications from neutropenia (fever and sepsis) occurred in 16 patients (40% of cases). The median time for neutropenic complications was 27 days (9-35), and 10/16 (62%) cases of neutropenic fever occurred after the second cycle of chemotherapy. The probability of Grade 3 or 4 late effects on platelets ( 9 /L) and hemoglobin (<8 g/dl) was 10% (95% CI 1, 20) and 6% (95% CI 2, 15), respectively. Of the 40 patients, 35 were able to complete 4 cycles of chemotherapy. There were no factors predictive for neutropenic toxicity at a p value < 0.05. Conclusions: The protocol has acceptable toxicity, and the treatment has been deliverable in a

  1. High risk Merkel cell carcinoma of the skin treated with synchronous carboplatin/etoposide and radiation: a trans-Tasman radiation oncology group study

    International Nuclear Information System (INIS)

    Poulsen, M.G.; Rischin, D.; Ainslie, J.; Walpole, E.; Harvey, J.; Mackintosh, J.; Hamilton, C.; Tripcony, L.

    2003-01-01

    The effectiveness of synchronous carboplatin, etoposide and radiation therapy was prospectively assessed in a group of patients with high risk Merkel Cell Carcinoma of the skin. Patients were eligible if they had disease localised to the primary site and nodes and were required to have at least one of the following high risk features: recurrence after initial therapy, involved nodes, primary size greater than 1 cm, gross residual disease after surgery or occult primary with nodes. Radiation was delivered to the primary site and nodes to a dose of 50 Gy in 25 fractions over 5 weeks and synchronous carboplatin (AUC 4.5) and etoposide 80 mg/M2 intravenously days 1-3 was given in weeks 1, 4, 7 and 10. The median age of the group was 67 [43-86] years and there were 39 males and 14 females. Involved nodes (stageII) were present in 33 (62%) cases. The sites involved in decreasing order were head and neck (22), occult primary (13), upper limb (8), lower limb (8) and trunk (2). Fifty-three patients were entered between 1996 and 2001.The median potential follow up was 48 months. There were no treatment related deaths. The 3 year overall survival, loco-regional control and distant control were 76%, 75% and 76% respectively. Factors that were predictive for local control and survival were tumour site and the presence of nodes. Multivariate analysis indicated that the major factor influencing survival was the presence of nodes. However this was not a significant factor in loco-regional control. High levels of loco-regional control and survival have been achieved with the addition of chemotherapy to radiation treatment for high risk Merkel cell carcinoma of skin. The role of chemo-radiotherapy for high risk MCC warrants further investigation

  2. Changes in the concentration of sulfhydryl groups in tissues of rats under the influence of gamma-radiation and adeturon

    International Nuclear Information System (INIS)

    Pantev, T.; Bychvarova, K.

    1984-01-01

    The concentration of SH-groups in the spleen, liver and bone marrow in rats was determined using the method of Sedlak and Lindsey. The changes in thiol level have been traced under the single influence of Adeturon and combined influence of radiation with 7,5 Gy and of Adeturon introduced 15 min before radiation. The animals were killed on 30th, 45th and 90th minute after the exerted influence. The control animals had physiological solution introduced. under the single influence of Adeturon there was increase in SH-groups mainly in the bone marrow in later terms after the exerted influence (the 90th minute), while P-SH in the spleen and liver decrease within the same term. The changes of NP-SH in the spleen and liver are opposite in nature. Under the influence of radiation P-SH in the liver and the spleen slightly decrease, while those in the bone marrow considerably increase on the 60th minute. NP-SH abruptly decrease on the 45th minute in the liver, while those in the spleen and bone marrow slightly differentiate from the control values. In animals protected by Adeturon P-SH in the bone marrow increase on the 30th and 45th minute, while those in the spleen decrease on the 90th minute. NP-SH decrease in the liver. The results obtained show that under the influence of Adeturon some changes occur in the level of thiols in tissues of both nonradiated and radiated animals

  3. Extra-nodal lymphoma. A survey of Japan lymphoma radiation therapy group

    International Nuclear Information System (INIS)

    Oguchi, Masahiko; Ikeda, Hiroshi; Nakamura, Shigeo

    2002-01-01

    The purpose of this study was to examine, retrospectively, national-wide clinical data of patients with localized extranodal non-Hodgkin's lymphoma (NHL) who were treated by radiation therapy with or without chemotherapy. The survey was carried out at 25 radiation oncology institutions in Japan in 1998. In 1999, according to the Revised European American Lymphoma (REAL) classification, central pathological review conducted at Aichi cancer center was carried out for the data from 7 radiation oncology institutions. The 5-year progression free survival rates (PFS) were calculated to identify prognostic factors. Survey: Data from 1, 141 patients with stage I and II NHL were recruited from 1988 through 1992. Of them, 787 patients, who were treated using definitive radiotherapy with or without chemotherapy for intermediate and high-grade lymphomas in Working Formulation, constituted the core of this study. Primary tumors arose mainly from extra-nodal organs (71%) in the head and neck (Waldeyer's ring: 41%, thyroid gland: 7%, nasal cavities: 5%, oral cavities: 4%, sinus: 3%, orbital structures: 3%, skin: 2% and etc.). The median age of 60 years for patients with extra-nodal NHL was higher than that of 56 years for patients with nodal NHL (p<0.01). Female were dominant in incidence of extra-nodal NHL arising from the thyroid gland, skin and gastrointestinal tract. The percentage of stage I to the extra-nodal NHL from orbit, sino-nasal presentation was higher than that of other NHLs. The percentage of stage II to the extra-nodal NHL from Waldeyer's ring and thyroid gland was higher than that of other NHLs. Central pathological review was carried out for pathological data from 79 patients (Waldeyer's ring: 45, thyroid gland: 19, sinonasal cavities: 15). Of these, diffuse large B cell lymphoma (DLBCL) composed 63% of all patients, mucosa associated lyumphoid tissue lymphoma (MALT-L): 16%, Natural Killer/T cell lymphoma (NK/T-L): 11%, and mantle cell lymphoma: 5% in REAL

  4. Australian radiation therapists' perceptions of the determinants of fitness to practise; a mixed methods focus group study

    International Nuclear Information System (INIS)

    Wright, Caroline A.; Schneider, Michal E.; Jolly, Brian; Baird, Marilyn A.

    2014-01-01

    Background: There is a lack of clarity as to what factors affect practitioners' fitness to practise (FTP). Purpose: The purpose of this study was to identify what radiation therapists perceived to be the key determinants of FTP and to establish the importance that they place on each determinant. Methods: A mixed methods approach using focus groups with a brainstorming activity was used for data collection. Qualitative analysis was informed by grounded theory, where the data was coded and assigned themes. Findings: Three focus groups were conducted with 21 participants. Twenty-one unique determinants of FTP were identified. Professional development, communication, competence, qualifications, ethics and professionalism were common themes in all focus groups. Knowledge, technical and professional skills were most frequently cited by participants as the three most important determinants. Self-awareness, values and ethics featured last on the list. Participants of higher seniority identified a greater variety of determinants with lesser emphasis on technical skills, when compared with junior participants. Nine determinant themes were identified initially and these were spliced to form three primary categories; Impairment, Competence, and Values/Ethics. Conclusion: The most important issues to radiation therapists were associated with technical and clinical competence. This indicates a need to further educate practitioners on the other determinants of FTP, such as values, ethics, probity, trust and criminal activity. Further investigation is required to assess practitioner behavioural responses to deviations from accepted practice and the socio-cultural context of FTP

  5. Simple introduction of sulfonic acid group onto polyethylene by radiation-induced cografting of sodium styrenesulfonate with hydrophilic monomers

    International Nuclear Information System (INIS)

    Tsuneda, Satoshi; Saito, Kyoichi; Furusaki, Shintaro; Sugo, Takanobu; Makuuchi, Keizo

    1993-01-01

    The sulfonic acid (SO 3 H) group was readily introduced into a polyethylene (PE) membrane by radiation-induced cografting of sodium styrenesulfonate (SSS) with hydrophilic monomers such as acrylic acid (AAc) and hydroxyethyl methacrylate (HEMA). The density of SSS grafted onto the PE membrane was determined as a function of molar ratio of hydrophilic monomer to SSS in the monomer mixture. Immersion of the electron-beam-irradiated PE membrane into the mixture of SSS and HEMA for 5 h at 323 K provided to the SO 3 H density of 2.5 mol/kg of the H-type product

  6. SU-E-P-22: AAPM Task Group 263 Tackling Standardization of Nomenclature for Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Matuszak, M; Feng, M [University of Michigan, Ann Arbor, MI (United States); Moran, J [Univ Michigan Medical Center, Ann Arbor, MI (United States); Xiao, Y [Thomas Jefferson University, Philadelphia, PA (United States); Mayo, C; Miller, R [Mayo Clinic, Rochester, MN (United States); Bosch, W [Washington Univ, Saint Louis, MO (United States); Popple, R [Univ Alabama Birmingham, Birmingham, AL (United States); Marks, L [UNC School of Medicine, Chapel Hill, NC (United States); Wu, Q [Duke University Medical Center, Durham, NC (United States); Molineu, A; Martel, M [UT MD Anderson Cancer Center, Houston, TX (United States); Yock, T [Massachusetts General Hospital, Boston, MA (United States); McNutt, T [Johns Hopkins University, Severna Park, MD (United States); Brown, N [Baptist Medical Center, Jacksonville, FL (United States); Purdie, T [Princess Margaret Hospital, Toronto, ON (Canada); Yorke, E [Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Santanam, L [Washington University School of Medicine, St.louis, MO (United States); Gabriel, P [University of Pennsylvania, Philadelphia, PA (United States); Michalski, J [Washington University, Saint Louis, MO (United States); and others

    2015-06-15

    Purpose: There is growing recognition of need for increased clarity and consistency in the nomenclatures used for body and organ structures, DVH metrics, toxicity, dose and volume units, etc. Standardization has multiple benefits; e.g. facilitating data collection for clinical trials, enabling the pooling of data between institutions, making transfers (i.e. hand-offs) between centers safer, and enabling vendors to define “default” settings. Towards this goal, the American Association of Physicists in Medicine (AAPM) formed a task group (TG263) in July of 2014, operating under the Work Group on Clinical Trials to develop consensus statements. Guiding principles derived from the investigation and example nomenclatures will be presented for public feedback. Methods: We formed a multi-institutional and multi-vendor collaborative group of 39 physicists, physicians and others involved in clinical use and electronic transfer of information. Members include individuals from IROC, NRG, IHE-RO, DICOM WG-7, ASTRO and EORTC groups with overlapping interests to maximize the quality of the consensus and increase the likelihood of adoption. Surveys of group and NRG members were used to define current nomenclatures and requirements. Technical requirements of vendor systems and the proposed DICOM standards were examined. Results: There is a marked degree of inter and intra institutional variation in current approaches, resulting from inter-vendor differences in capabilities, clinic specific conceptualizations and inconsistencies. Using a consensus approach, the group defined optimal formats for the naming of targets and normal structures. A formal objective assessment of 13 existing clinically-used software packages show that all had capabilities to accommodate these recommended nomenclatures. Conclusions: A multi-stakeholder effort is making significant steps forward in developing a standard nomenclature that will work across platforms. Our current working list includes > 550

  7. Analysis of toxicity in a group of patients treated for pancreatic cancer with combined modality 3D radiation therapy

    International Nuclear Information System (INIS)

    Fine, Robert M.; Fernandez-Vicioso, Eduardo; Higgins, Patrick; Schell, Michael; Sohn, Jason; Pelley, Robert; Walsh, R. M.; Vogt, David; Hermann, Robert

    1995-01-01

    Purpose: To evaluate the acute toxicity of a group of 37 pancreatic cancer patients treated with noncoplanar, nonopposed, conformal radiation therapy with concurrent chemotherapy (5-FU). Materials and Methods: We retrospectively evaluated a group of initially nonadvanced 37 pancreatic cancer patients treated with combined concurrent chemotherapy and 3D radiation therapy treated between 1992 until 1995. During this period we began treating the initially unresectable patients with preoperative chemo-RT (50.4 Gy) after treating an initial group of unresectable patients to a higher dose of 66.6 Gy. We also include a group of patients who received postop chemo-RT after Whipple resection (59.4 Gy). All radiation was delivered at a 1.8 Gy per fraction dose rate. The total group was made up of 37 patients of whom 21 were male (57%) and 16 female (43%). There were 22 (59%) head of pancreas lesions, 10 (27%) body of pancreas lesions, and 5 (14%) head and body of pancreas cancers. Of these 37 patients 7 (19%) were treated with chemo-RT as their only treatment, 10 patients (29%) were treated post Whipple resection, and 20 patients (54%) were treated with preoperative intent. Results: Three patients (8%) required a treatment break, one with a body and 2 with head lesions. Two of these patients stopped RT short of planned dose (32.56 and 46.8 Gy) both suffering from nausea, vomiting, and anorexia with the third, who finished a planned 66.6 Gy dose, after a 4 day rest for leukopenia. One of 20 patients (5%) preop patients underwent the planned post chemo-RT Whipple resection, while 4 of the 20 patients (20%), remained unresectable, but without disease progression and had Iodine 125 interstitial implants at exploration delivering a minimal tumor dose of 120 Gy on top or the 50.4 Gy delivered preoperatively. Four patients (11%) maintained a minimal Karnofsky score of 100, 23 patients (62%) maintained a minimal KPS of 90, 6 patients (16%) maintained a minimal KPS of 80, and 4

  8. Misonidazole and unconventional radiation in advanced squamous cell carcinoma of the esophagus: a phase II study of the Radiation Therapy Oncology Group

    International Nuclear Information System (INIS)

    Ydrach, A.A.; Marcial, V.A.; Parsons, J.; Concannon, J.; Asbell, S.O.; George, F.

    1982-01-01

    This is a report on Radiation Therapy Oncology Group (RTOG) Protocol78-32, a Phase I/II prospective study aimed at determining tolerance, tumor response, and survival of squamous cell carcinoma of the esophagus treated with unorthodox fractionation radiotherapy combined with misonidazole. Misonidazole was administered by mouth 4 to 6 hr prior to radiation, at a dose of 1.0 to 1.25 Gm/.m 2 ; blood levels were measured at about 4 hr after intake of the drug and reported in micrograms/ml. Radiotherapy was administered at 4 to 6 hr post-misonidazole dose and given with 400 rad fractions, alternating 2 or 3 times/week, up to 4,800 rad. A total of 43 patients were entered; 26 are evaluated for survival at 1 year post accession. Thirty patients (88%) received the planned radiation course. Twenty-eight patients (78%) received the planned misonidazole dosage. Tumor response, evaluated in 18 patients, showed a complete regression (C.R.) in only 2 patients (11%); and partial response (P.R.) in 6 patients (33%). Eight patients (44%) showed no tumor response to planned therapy. Toxicity was acceptable and in 38 evaluated patients only 4 reported (11%) nausea and vomiting, 7 reported mild paresthesias (18%). The median survival was only five months. In 26 patients evaluated for 1 year survival determination, only 1 survived (3.8%) this period. In view of the poor tumor response and low survival observed, we do not recommend that this particular fractionation regimen with misonidazole be used in a Phase III randomized trial in squamous cell carcinoma of the esophagus

  9. Dose Specification and Quality Assurance of Radiation Therapy Oncology Group Protocol 95-17; a Cooperative Group Study of Iridium-192 Breast Implants as Sole Therapy

    International Nuclear Information System (INIS)

    Ibbott, Geoffrey S.; Hanson, W.F.; O'Meara, Elizabeth; Kuske, Robert R.; Arthur, Douglas; Rabinovitch, Rachel; White, Julia; Wilenzick, Raymond M.; Harris, Irene; Tailor, Ramesh C.

    2007-01-01

    Purpose: The Radiation Therapy Oncology Group (RTOG) protocol 95-17 was a Phase I/II trial to evaluate multicatheter brachytherapy as the sole method of adjuvant breast radiotherapy for Stage I/II breast carcinoma after breast-conserving surgery. Low- or high-dose-rate sources were allowed. Dose prescription and treatment evaluation were based on recommendations in the International Commission on Radiation Units and Measurements (ICRU), Report 58 and included the parameters mean central dose (MCD), average peripheral dose, dose homogeneity index (DHI), and the dimensions of the low- and high-dose regions. Methods and Materials: Three levels of quality assurance were implemented: (1) credentialing of institutions was required before entering patients into the study; (2) rapid review of each treatment plan was conducted before treatment; and (3) retrospective review was performed by the Radiological Physics Center in conjunction with the study chairman and RTOG dosimetry staff. Results: Credentialing focused on the accuracy of dose calculation algorithm and compliance with protocol guidelines. Rapid review was designed to identify and correct deviations from the protocol before treatment. The retrospective review involved recalculation of dosimetry parameters and review of dose distributions to evaluate the treatment. Specifying both central and peripheral doses resulted in uniform dose distributions, with a mean dose homogeneity index of 0.83 ± 0.06. Conclusions: Vigorous quality assurance resulted in a high-quality study with few deviations; only 4 of 100 patients were judged as representing minor variations from protocol, and no patient was judged as representing major deviation. This study should be considered a model for quality assurance of future trials

  10. Human genetic studies in areas of high natural radiation VI. Genetical load and ethnic group

    Energy Technology Data Exchange (ETDEWEB)

    Freire-Maia, A [Faculdade de Ciencias Medicas e Biologicas de Botucatu (Brazil). Departamento de Genetica

    1974-01-01

    The load of mutations disclosed by inbreeding, according to the ethnic group of the parents, has been analyzed in our data. Besides the total of the population, a sample with no alien ancestrals has also been analyzed. Genetic load has been studied for absortions, still births, pos-natal mortality, total mortality, anomalies, total mortality + anomalies, and abnormalities in general.

  11. Human genetic studies in areas of high natural radiation VI. Genetical load and ethnic group

    International Nuclear Information System (INIS)

    Freire-Maia, A.

    1974-01-01

    The load of mutations disclosed by inbreeding, according to the ethnic group of the parents, has been analyzed in our data. Besides the total of the population, a sample with no alien ancestrals has also been analyzed. Genetic load has been studied for absortions, still births, pos-natal mortality, total mortality, anomalies, total mortality + anomalies, and abnormalities in general [pt

  12. Monophosphate end groups produced in radiation induced strand breakage in DNA

    International Nuclear Information System (INIS)

    Kay, E.; Ward, J.F.

    1976-01-01

    A solution of DNA was gamma-irradiated and treated with monophosphatase for studies on the amount of inorganic phosphate released as a function of time. Studies were also conducted on: effect of alkali on yield of monophosphate end groups; induction of DNA strand breaks by treatment with DNAase; initial G values for monophosphate termini; and effect of alkali on radioinduced DNA damage

  13. Modelling the exposure of wildlife to radiation: key findings and activities of IAEA working groups

    Energy Technology Data Exchange (ETDEWEB)

    Beresford, Nicholas A. [NERC Centre for Ecology and Hydrology, Lancaster Environment Center, Library Av., Bailrigg, Lancaster, LA1 4AP (United Kingdom); School of Environment and Life Sciences, University of Salford, Manchester, M4 4WT (United Kingdom); Vives i Batlle, Jordi; Vandenhove, Hildegarde [Belgian Nuclear Research Centre, Belgian Nuclear Research Centre, Boeretang 200, 2400 Mol (Belgium); Beaugelin-Seiller, Karine [Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, LM2E, Cadarache (France); Johansen, Mathew P. [ANSTO Australian Nuclear Science and Technology Organisation, New Illawarra Rd, Menai, NSW (Australia); Goulet, Richard [Canadian Nuclear Safety Commission, Environmental Risk Assessment Division, 280 Slater, Ottawa, K1A0H3 (Canada); Wood, Michael D. [School of Environment and Life Sciences, University of Salford, Manchester, M4 4WT (United Kingdom); Ruedig, Elizabeth [Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins (United States); Stark, Karolina; Bradshaw, Clare [Department of Ecology, Environment and Plant Sciences, Stockholm University, SE-10691 (Sweden); Andersson, Pal [Swedish Radiation Safety Authority, SE-171 16, Stockholm (Sweden); Copplestone, David [Biological and Environmental Sciences, University of Stirling, Stirling, FK9 4LA (United Kingdom); Yankovich, Tamara L.; Fesenko, Sergey [International Atomic Energy Agency, Vienna International Centre, 1400, Vienna (Austria)

    2014-07-01

    In total, participants from 14 countries, representing 19 organisations, actively participated in the model application/inter-comparison activities of the IAEA's EMRAS II programme Biota Modelling Group. A range of models/approaches were used by participants (e.g. the ERICA Tool, RESRAD-BIOTA, the ICRP Framework). The agreed objectives of the group were: 'To improve Member State's capabilities for protection of the environment by comparing and validating models being used, or developed, for biota dose assessment (that may be used) as part of the regulatory process of licensing and compliance monitoring of authorised releases of radionuclides.' The activities of the group, the findings of which will be described, included: - An assessment of the predicted unweighted absorbed dose rates for 74 radionuclides estimated by 10 approaches for five of the ICRPs Reference Animal and Plant geometries assuming 1 Bq per unit organism or media. - Modelling the effect of heterogeneous distributions of radionuclides in sediment profiles on the estimated exposure of organisms. - Model prediction - field data comparisons for freshwater ecosystems in a uranium mining area and a number of wetland environments. - An evaluation of the application of available models to a scenario considering radioactive waste buried in shallow trenches. - Estimating the contribution of {sup 235}U to dose rates in freshwater environments. - Evaluation of the factors contributing to variation in modelling results. The work of the group continues within the framework of the IAEA's MODARIA programme, which was initiated in 2012. The work plan of the MODARIA working group has largely been defined by the findings of the previous EMRAS programme. On-going activities of the working group, which will be described, include the development of a database of dynamic parameters for wildlife dose assessment and exercises involving modelling the exposure of organisms in the marine coastal

  14. EORTC Radiation Oncology Group quality assurance platform: Establishment of a digital central review facility

    International Nuclear Information System (INIS)

    Fairchild, Alysa; Aird, Edwin; Fenton, Paul A.; Gregoire, Vincent; Gulyban, Akos; Lacombe, Denis; Matzinger, Oscar; Poortmans, Philip; Ruyskart, Pascal; Weber, Damien C.; Hurkmans, Coen W.

    2012-01-01

    Objective: Quality assurance (QA) in clinical trials is essential to ensure treatment is safely and effectively delivered. As QA requirements have increased in complexity in parallel with evolution of radiation therapy (RT) delivery, a need to facilitate digital data exchange emerged. Our objective is to present the platform developed for the integration and standardization of QART activities across all EORTC trials involving RT. Methods: The following essential requirements were identified: secure and easy access without on-site software installation; integration within the existing EORTC clinical remote data capture system; and the ability to both customize the platform to specific studies and adapt to future needs. After retrospective testing within several clinical trials, the platform was introduced in phases to participating sites and QART study reviewers. Results: The resulting QA platform, integrating RT analysis software installed at EORTC Headquarters, permits timely, secure, and fully digital central DICOM-RT based data review. Participating sites submit data through a standard secure upload webpage. Supplemental information is submitted in parallel through web-based forms. An internal quality check by the QART office verifies data consistency, formatting, and anonymization. QART reviewers have remote access through a terminal server. Reviewers evaluate submissions for protocol compliance through an online evaluation matrix. Comments are collected by the coordinating centre and institutions are informed of the results. Conclusions: This web-based central review platform facilitates rapid, extensive, and prospective QART review. This reduces the risk that trial outcomes are compromised through inadequate radiotherapy and facilitates correlation of results with clinical outcomes.

  15. Modern Radiation Therapy for Nodal Non-Hodgkin Lymphoma—Target Definition and Dose Guidelines From the International Lymphoma Radiation Oncology Group

    Energy Technology Data Exchange (ETDEWEB)

    Illidge, Tim, E-mail: Tim.Illidge@ics.manchester.ac.uk [Institute of Cancer Sciences, University of Manchester, Manchester Academic Health Sciences Centre, The Christie National Health Service Foundation Trust, Manchester (United Kingdom); Specht, Lena [Department of Oncology and Hematology, Rigshospitalet, University of Copenhagen, Copenhagen (Denmark); Yahalom, Joachim [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Aleman, Berthe [Department of Radiotherapy, The Netherlands Cancer Institute, Amsterdam (Netherlands); Berthelsen, Anne Kiil [Department of Radiation Oncology and PET Centre, Rigshospitalet, University of Copenhagen, Copenhagen (Denmark); Constine, Louis [Departments of Radiation Oncology and Pediatrics, James P. Wilmot Cancer Center, University of Rochester Medical Center, Rochester, New York (United States); Dabaja, Bouthaina [Division of Radiation Oncology, Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Dharmarajan, Kavita [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Ng, Andrea [Department of Radiation Oncology, Brigham and Women' s Hospital and Dana-Farber Cancer Institute, Harvard University, Boston, Massachusetts (United States); Ricardi, Umberto [Radiation Oncology Unit, Department of Oncology, University of Torino, Torino (Italy); Wirth, Andrew [Division of Radiation Oncology, Peter MacCallum Cancer Institute, St. Andrews Place, East Melbourne (Australia)

    2014-05-01

    Radiation therapy (RT) is the most effective single modality for local control of non-Hodgkin lymphoma (NHL) and is an important component of therapy for many patients. Many of the historic concepts of dose and volume have recently been challenged by the advent of modern imaging and RT planning tools. The International Lymphoma Radiation Oncology Group (ILROG) has developed these guidelines after multinational meetings and analysis of available evidence. The guidelines represent an agreed consensus view of the ILROG steering committee on the use of RT in NHL in the modern era. The roles of reduced volume and reduced doses are addressed, integrating modern imaging with 3-dimensional planning and advanced techniques of RT delivery. In the modern era, in which combined-modality treatment with systemic therapy is appropriate, the previously applied extended-field and involved-field RT techniques that targeted nodal regions have now been replaced by limiting the RT to smaller volumes based solely on detectable nodal involvement at presentation. A new concept, involved-site RT, defines the clinical target volume. For indolent NHL, often treated with RT alone, larger fields should be considered. Newer treatment techniques, including intensity modulated RT, breath holding, image guided RT, and 4-dimensional imaging, should be implemented, and their use is expected to decrease significantly the risk for normal tissue damage while still achieving the primary goal of local tumor control.

  16. Survey of Stereotactic Body Radiation Therapy in Japan by the Japan 3-D Conformal External Beam Radiotherapy Group

    International Nuclear Information System (INIS)

    Nagata, Yasushi; Hiraoka, Masahiro; Mizowaki, Takashi; Narita, Yuichiro; Matsuo, Yukinori; Norihisa, Yoshiki; Onishi, Hiroshi; Shirato, Hiroki

    2009-01-01

    Purpose: To recognize the current status of stereotactic body radiotherapy (SBRT) in Japan, using a nationwide survey conducted by the Japan 3-D Conformal External Beam Radiotherapy Group. Methods and Materials: The questionnaire was sent by mail to 117 institutions. Ninety-four institutions (80%) responded by the end of November 2005. Fifty-three institutions indicated that they have already started SBRT, and 38 institutions had been reimbursed by insurance. Results: A total of 1111 patients with histologically confirmed lung cancer were treated. Among these patients, 637 had T1N0M0 and 272 had T2N0M0 lung cancer. Metastatic lung cancer was found in 702 and histologically unconfirmed lung tumor in 291 patients. Primary liver cancer was found in 207 and metastatic liver cancer in 76 patients. The most frequent schedule used for primary lung cancer was 48Gy in 4 fractions at 22 institutions (52%), followed by 50Gy in 5 fractions at 11 institutions (26%) and 60Gy in 8 fractions at 4 institutions (10%). The tendency was the same for metastatic lung cancer. The average number of personnel involved in SBRT was 1.8 radiation oncologists, including 1.1 certified radiation oncologists, 2.8 technologists, 0.7 nurses, and 0.6 certified quality assurance personnel and 0.3 physicists. The most frequent amount of time for treatment planning was 61-120min, for quality assurance was 50-60min, and for treatment was 30min. There were 14 (0.6% of all cases) reported Grade 5 complications: 11 cases of radiation pneumonitis, 2 cases of hemoptysis, and 1 case of radiation esophagitis. Conclusion: The current status of SBRT in Japan was surveyed.

  17. Final report of the specific research. Investigations on the analysis of bio-protective factors against radiation. 1998-2000 FY (Research Group of NIRS)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-03-01

    This report concerns investigations in the title conducted by 8 groups of National Institute of Radiological Sciences (NIRS) during the period of 1998-2000. The groups are for investigation of: Effects of p53 tumor suppressor gene in radiation-induced leukemia, Role of atm-gene in dose rate effect of ionizing radiation, Function of DNA-dependent protein kinase catalytic subunit (DNA-PK{sub cs}), Functional complementation of radiation-sensitive mutant M10 cell line by human XRCC4 cDNA expression, Role of radiation-induced apoptosis in digital defects in embryonic mice, Functional analysis of S-phase specific novel nuclear protein NP95 by gene targeting, Role of chemokine in T cell development and lymphomagenesis, and establishment of production techniques of gene-modified mice using embryonic stem cells for genetic analysis of radiation-sensitive genes. The groups describe summaries of their studies and published original articles are also given. (N.I.)

  18. Final report of the specific research. Investigations on the analysis of bio-protective factors against radiation. 1998-2000 FY (Research Group of NIRS)

    International Nuclear Information System (INIS)

    2002-03-01

    This report concerns investigations in the title conducted by 8 groups of National Institute of Radiological Sciences (NIRS) during the period of 1998-2000. The groups are for investigation of: Effects of p53 tumor suppressor gene in radiation-induced leukemia, Role of atm-gene in dose rate effect of ionizing radiation, Function of DNA-dependent protein kinase catalytic subunit (DNA-PK cs ), Functional complementation of radiation-sensitive mutant M10 cell line by human XRCC4 cDNA expression, Role of radiation-induced apoptosis in digital defects in embryonic mice, Functional analysis of S-phase specific novel nuclear protein NP95 by gene targeting, Role of chemokine in T cell development and lymphomagenesis, and establishment of production techniques of gene-modified mice using embryonic stem cells for genetic analysis of radiation-sensitive genes. The groups describe summaries of their studies and published original articles are also given. (N.I.)

  19. Radiation phenomena of plasma waves, 1

    International Nuclear Information System (INIS)

    Ohnuma, Toshiro.

    1978-06-01

    The fundamental radiation theories on radiation phenomena of plasma waves are presented. As the fundamental concepts of propagating waves, phase, group and ray velocities are explained, and phase velocity surface, group velocity surface, ray velocity surface and refractive index surface are considered. These concepts are important in anisotropic plasma. Fundamental equations for electron plasma waves in a fluid model and fundamental equations for ion plasma waves can be expressed with the above mentioned concepts. Kuehl derived the formulas for general radiation fields of electromagnetic and electrostatic waves which are radiated from an arbitrary current source. Fundamental equations for kinetic model are the Vlasov equation and Maxwell equations. By investigating electromagnetic radiation in cold anisotropic plasma, Kuehl found the important behavior that the fields radiated from a source become very large in certain directions for some ranges of plasma parameters. The fact is the so-called high frequency resonance cone. A fundamental formula for quasi-static radiation from an oscillating point source in warm anisotropic plasma includes the near field of electromagnetic mode and the field of electrostatic mode, which are radiated from the source. This paper presents the formula in a generalized form. (Kato, T.)

  20. Repair of ultraviolet radiation damage in xeroderma pigmentosum cells belonging to complementation group F

    International Nuclear Information System (INIS)

    Hayakawa, H.; Ishizaki, K.; Yagi, T.; Takebe, H.; Inoue, M.; Sekiguchi, M.; Kyoto Univ.

    1981-01-01

    DNA-repair characteristics of xeroderma pigmentosum belonging to complementation group F were investigated. The cells exhibited an intermediate level of repair as measured in terms of (1) disappearance of T4 endonuclease-V-susceptible sites from DNA, (2) formation of ultraviolet-induced strand breaks in DNA, and (3) ultraviolet-induced unscheduled DNA synthesis during post-irradiation incubation. The impaired ability of XP3YO to perform unscheduled DNA synthesis was restored, to half the normal level, by the concomitant treatment with T4 endonuclease V and ultraviolet-inactivated Sendai virus. It is suggested that xeroderma pigmentosum cells of group F may be defective, at least in part, in the incision step of excision repair. (orig.)

  1. Insufficiency Fractures After Pelvic Radiation Therapy for Uterine Cervical Cancer: An Analysis of Subjects in a Prospective Multi-institutional Trial, and Cooperative Study of the Japan Radiation Oncology Group (JAROG) and Japanese Radiation Oncology Study Group (JROSG)

    Energy Technology Data Exchange (ETDEWEB)

    Tokumaru, Sunao, E-mail: tokumaru@cc.saga-u.ac.jp [Department of Heavy Particle Therapy and Radiation Oncology, Saga University, Saga (Japan); Toita, Takafumi [Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Okinawa (Japan); Oguchi, Masahiko [Radiation Oncology Department, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo (Japan); Ohno, Tatsuya [Gunma University Heavy Ion Medical Center, Maebashi (Japan); Kato, Shingo [Department of Radiation Oncology, Saitama Medical University, International Medical Center, Saitama (Japan); Niibe, Yuzuru [Department of Radiology, School of Medicine, Kitasato University, Sagamihara (Japan); Kazumoto, Tomoko [Department of Radiology, Saitama Cancer Center, Saitama (Japan); Kodaira, Takeshi [Department of Radiation Oncology, Aichi Cancer Center, Nagoya (Japan); Kataoka, Masaaki [Department of Radiology, National Shikoku Cancer Center, Matsuyama (Japan); Shikama, Naoto [Department of Radiation Oncology, Saitama Medical University, International Medical Center, Saitama (Japan); Kenjo, Masahiro [Department of Radiation Oncology, Graduate School of Medical Science, Hiroshima University, Hiroshima (Japan); Yamauchi, Chikako [Department of Radiation Oncology, Shiga Medical Center for Adults, Moriyama (Japan); Suzuki, Osamu [Department of Radiation Oncology, Osaka Medical Center for Cancer, Osaka (Japan); Sakurai, Hideyuki [Proton Medical Research Center and Tsukuba University, Tuskuba (Japan); Teshima, Teruki [Department of Medical Physics and Engineering, Graduate School of Medicine, Osaka University, Suita (Japan); Kagami, Yoshikazu [Department of Radiology, Showa University School of Medicine, Tokyo (Japan); Nakano, Takashi [Department of Radiation Oncology, Gunma University, Graduate School of Medicine, Maebashi (Japan); Hiraoka, Masahiro [Department of Radiation Oncology and Image-applied Therapy, Kyoto University, Graduate School of Medicine, Kyoto (Japan); and others

    2012-10-01

    Purpose: To investigate pelvic insufficiency fractures (IF) after definitive pelvic radiation therapy for early-stage uterine cervical cancer, by analyzing subjects of a prospective, multi-institutional study. Materials and Methods: Between September 2004 and July 2007, 59 eligible patients were analyzed. The median age was 73 years (range, 37-84 years). The International Federation of Gynecologic Oncology and Obstetrics stages were Ib1 in 35, IIa in 12, and IIb in 12 patients. Patients were treated with the constant method, which consisted of whole-pelvic external-beam radiation therapy of 50 Gy/25 fractions and high-dose-rate intracavitary brachytherapy of 24 Gy/4 fractions without chemotherapy. After radiation therapy the patients were evaluated by both pelvic CT and pelvic MRI at 3, 6, 12, 18, and 24 months. Diagnosis of IF was made when the patients had both CT and MRI findings, neither recurrent tumor lesions nor traumatic histories. The CT findings of IF were defined as fracture lines or sclerotic linear changes in the bones, and MRI findings of IF were defined as signal intensity changes in the bones, both on T1- and T2-weighted images. Results: The median follow-up was 24 months. The 2-year pelvic IF cumulative occurrence rate was 36.9% (21 patients). Using Common Terminology Criteria for Adverse Events version 3.0, grade 1, 2, and 3 IF were seen in 12 (21%), 6 (10%), and 3 patients (5%), respectively. Sixteen patients had multiple fractures, so IF were identified at 44 sites. The pelvic IF were frequently seen at the sacroileal joints (32 sites, 72%). Nine patients complained of pain. All patients' pains were palliated by rest or non-narcotic analgesic drugs. Higher age (>70 years) and low body weight (<50 kg) were thought to be risk factors for pelvic IF (P=.007 and P=.013, Cox hazard test). Conclusions: Cervical cancer patients with higher age and low body weight may be at some risk for the development of pelvic IF after pelvic radiation therapy.

  2. Quality assurance for computed-tomography simulators and the computed-tomography-simulation process: Report of the AAPM Radiation Therapy Committee Task Group No. 66

    International Nuclear Information System (INIS)

    Mutic, Sasa; Palta, Jatinder R.; Butker, Elizabeth K.; Das, Indra J.; Huq, M. Saiful; Loo, Leh-Nien Dick; Salter, Bill J.; McCollough, Cynthia H.; Van Dyk, Jacob

    2003-01-01

    This document presents recommendations of the American Association of Physicists in Medicine (AAPM) for quality assurance of computed-tomography- (CT) simulators and CT-simulation process. This report was prepared by Task Group No. 66 of the AAPM Radiation Therapy Committee. It was approved by the Radiation Therapy Committee and by the AAPM Science Council

  3. Characteristic wave velocities in spherical electromagnetic cloaks

    International Nuclear Information System (INIS)

    Yaghjian, A D; Maci, S; Martini, E

    2009-01-01

    We investigate the characteristic wave velocities in spherical electromagnetic cloaks, namely, phase, ray, group and energy-transport velocities. After deriving explicit expressions for the phase and ray velocities (the latter defined as the phase velocity along the direction of the Poynting vector), special attention is given to the determination of group and energy-transport velocities, because a cursory application of conventional formulae for local group and energy-transport velocities can lead to a discrepancy between these velocities if the permittivity and permeability dyadics are not equal over a frequency range about the center frequency. In contrast, a general theorem can be proven from Maxwell's equations that the local group and energy-transport velocities are equal in linear, lossless, frequency dispersive, source-free bianisotropic material. This apparent paradox is explained by showing that the local fields of the spherical cloak uncouple into an E wave and an H wave, each with its own group and energy-transport velocities, and that the group and energy-transport velocities of either the E wave or the H wave are equal and thus satisfy the general theorem.

  4. Radiation hardening: study of production velocity and post-irradiation recovery of defect clusters produced by neutron irradiation at 77 K

    International Nuclear Information System (INIS)

    Gonzalez, Hector C.; Miralles, Monica T.

    1999-01-01

    This work includes three basic studies using radiation hardening of Cu single crystals irradiated at 77 K in the RA-1-reactor of CNEA: 1) The initial of a production curve of defect clusters originated during radiation until 5.2 x 10 20 n m 2 . The shape of the curve is compared with those obtained from measurement of resistivity increased (Δρ) with neutronic doses (φt) and the acceptance of the linear dependency of Δρ with Frenkel Pairs concentration (PFs); 2) The isochronal hardening recovery in the temperature interval of stage V (T > 450 K). The existence of the sub-stages Vb (∼ 550 K) and Vc (∼ 587 K), determined for the first time from hardening measurements, are shown and compared with results obtained by other techniques; 3) Isothermal recoveries performed in the temperature interval of the sub-stage Vc to determine phenomenologically the apparent activation energy of the sub-stage. The value obtained was in agreement with the energy for Cu vacancies auto diffusion. (author)

  5. Erosion of the 4-6- and 8 group transition metals under intense laser radiation

    International Nuclear Information System (INIS)

    Samsonov, G.V.; Verkhoturov, A.D.; Roshchina, A.I.; Vasil'ev, A.V.; Klimenko, V.P.

    1976-01-01

    The erosion resistance is studied of transition metals of Groups 4-6 and 8 at laser emission of approximately 6x1O 7 W/cm 2 . It is shown that as the emission power increases from 10 6 to 6x10 7 W/cm 2 the erosion values show an increase over tenfold without any subsequent filling of the craters. The growth of the metallic erosion is largely caused by a greater crater diameter. The erosion resistance of metals enhances in the following series: Ti-Zr-Co-Ni-Fe, Hf-V-Nb-Mo-Cr-Ta-W-Cu

  6. Radiations

    International Nuclear Information System (INIS)

    Pujol Mora, J.

    1999-01-01

    The exposition to ionizing radiations is a constant fact in the life of the human being and its utilization as diagnostic and therapeutic method is generalized. However, it is notorious how as years go on, the fear to the ionizing radiation seems to persist too, and this fact is not limited to the common individual, but to the technical personnel and professional personnel that labors with them same. (S. Grainger) [es

  7. Radiation

    International Nuclear Information System (INIS)

    Davidson, J.H.

    1986-01-01

    The basic facts about radiation are explained, along with some simple and natural ways of combating its ill-effects, based on ancient healing wisdom as well as the latest biochemical and technological research. Details are also given of the diet that saved thousands of lives in Nagasaki after the Atomic bomb attack. Special comment is made on the use of radiation for food processing. (U.K.)

  8. Calculus of radiolytic products generation in water due to alpha radiation. Determination of the spent nuclear fuels matrix alteration rate Determination of velocity of spent fuel matrix

    International Nuclear Information System (INIS)

    Quinones, J.; Serrano, J.; Diaz Arocas, P.; Rodriguez Almazan, J. L.; Bruno, J.; Cera, E.; Merino, J.; Esteban, J. A.; Martinez-Esparza, A.

    2000-01-01

    The generation of radiolytic products as a result of alpha radiation in the surface of the spent fuel is a key process in order to understand how the it becomes degraded in repository conditions. The present work has established a radiolytic model based on a set of reactions involving fuel oxidation-dissolution and radiolytic products recombination. It also includes the decrease of the dose rates as the main alpha emitters decay away. Four cases, with varying parameters of the system, have been assessed. The results show a decrease in both the concentration of the radiolytic products in the gap water and the degradation of the fuel matrix. It has been estimated that in the period of the evaluation (10''6 years) up to 52% of the pellet is altered in the conservative cases, whereas only 11% is altered in the realistic cases. No significant differences were observed when the carbonates reactions were included in the system. (Author)

  9. Radiation

    International Nuclear Information System (INIS)

    Winther, J.F.; Ulbak, K.; Dreyer, L.; Pukkala, E.; Oesterlind, A.

    1997-01-01

    Exposure to solar and ionizing radiation increases the risk for cancer in humans. Some 5% of solar radiation is within the ultraviolet spectrum and may cause both malignant melanoma and non-melanocytic skin cancer; the latter is regarded as a benign disease and is accordingly not included in our estimation of avoidable cancers. Under the assumption that the rate of occurrence of malignant melanoma of the buttocks of both men and women and of the scalp of women would apply to all parts of the body in people completely unexposed to solar radiation, it was estimated that approximately 95% of all malignant melanomas arising in the Nordic populations around the year 2000 will be due to exposure to natural ultraviolet radiation, equivalent to an annual number of about 4700 cases, with 2100 in men and 2600 in women, or some 4% of all cancers notified. Exposure to ionizing radiation in the Nordic countries occurs at an average effective dose per capita per year of about 3 mSv (Iceland, 1.1 mSv) from natural sources, and about 1 mSv from man-made sources. While the natural sources are primarily radon in indoor air, natural radionuclides in food, cosmic radiation and gamma radiation from soil and building materials, the man-made sources are dominated by the diagnostic and therapeutic use of ionizing radiation. On the basis of measured levels of radon in Nordic dwellings and associated risk estimates for lung cancer derived from well-conducted epidemiological studies, we estimated that about 180 cases of lung cancer (1% of all lung cancer cases) per year could be avoided in the Nordic countries around the year 2000 if indoor exposure to radon were eliminated, and that an additional 720 cases (6%) could be avoided annually if either radon or tobacco smoking were eliminated. Similarly, it was estimated that the exposure of the Nordic populations to natural sources of ionizing radiation other than radon and to medical sources will each give rise to an annual total of 2120

  10. Elective Clinical Target Volumes for Conformal Therapy in Anorectal Cancer: A Radiation Therapy Oncology Group Consensus Panel Contouring Atlas

    International Nuclear Information System (INIS)

    Myerson, Robert J.; Garofalo, Michael C.; El Naqa, Issam; Abrams, Ross A.; Apte, Aditya; Bosch, Walter R.; Das, Prajnan; Gunderson, Leonard L.; Hong, Theodore S.; Kim, J.J. John; Willett, Christopher G.; Kachnic, Lisa A.

    2009-01-01

    Purpose: To develop a Radiation Therapy Oncology Group (RTOG) atlas of the elective clinical target volume (CTV) definitions to be used for planning pelvic intensity-modulated radiotherapy (IMRT) for anal and rectal cancers. Methods and Materials: The Gastrointestinal Committee of the RTOG established a task group (the nine physician co-authors) to develop this atlas. They responded to a questionnaire concerning three elective CTVs (CTVA: internal iliac, presacral, and perirectal nodal regions for both anal and rectal case planning; CTVB: external iliac nodal region for anal case planning and for selected rectal cases; CTVC: inguinal nodal region for anal case planning and for select rectal cases), and to outline these areas on individual computed tomographic images. The imaging files were shared via the Advanced Technology Consortium. A program developed by one of the co-authors (I.E.N.) used binomial maximum-likelihood estimates to generate a 95% group consensus contour. The computer-estimated consensus contours were then reviewed by the group and modified to provide a final contouring consensus atlas. Results: The panel achieved consensus CTV definitions to be used as guidelines for the adjuvant therapy of rectal cancer and definitive therapy for anal cancer. The most important difference from similar atlases for gynecologic or genitourinary cancer is mesorectal coverage. Detailed target volume contouring guidelines and images are discussed. Conclusion: This report serves as a template for the definition of the elective CTVs to be used in IMRT planning for anal and rectal cancers, as part of prospective RTOG trials.

  11. Preventive and curative role of mezo-inosite B group vitamin in radiation disease

    International Nuclear Information System (INIS)

    Perepelkin, S.P.; Egorova, N.D.; Katsitadze, V.A.

    1977-01-01

    The effect of mezo-inosite (optically nonactive stereoisomer of inosite B group vitamine) having vitamin properties has been studied. Investigations were carried out with nonpedigree male rats. Mezo-inosite was used perorally in two variants of doses: according to the first variant - 2, 5, 10 mg per rat, according to the second variant - 1, 2, 2.5 and 5 mg per rat, which were conditionally named as doses of daily man organism demand, minimum therapeutic and therapeutic doses, respectively. Mezo-inosite was added into the rat ration for 21 days before irradiation and for 30-33 days after irradiation. The animals were exposed to 600 R total X-ray irradiation. Strong protective mezo-inosite effect (particularly at small doses, used in the second variant) in irradiation disease against a background of physiological diet application has been established. These data are confirmed by high animal survival, some increased duration of animal life,some more weight increase for the first ten-day period after irradiation and a comparatively better normalization of leucocytic composition of peripherical blood of the experimental animals, getting mezoinosite, in comparison with the controls

  12. Height and weight distribution of lower-middle income group of radiation workers

    International Nuclear Information System (INIS)

    Datta, S.; Sharma, R.C.; Sunta, C.M.

    1982-01-01

    Workers in the nuclear industry who are occasionally exposed to a radioactive environment were monitored for possible internal contamination. Calibration of the detection equipment was carried out with the help of a phantom. It is imperative that the phantom should have the physical dimensions of the subjects being monitored. As a step towards evolving a reference phantom, the height and weight distribution of the workers has been studied. The subjects included in this study are from lower middle income group drawing salaries between Rs 500 to 1000 per month. Mean weight +- SD was found to be 56.2 +- 8.70 kg and height 167 +- 5.90 cm. these averages match well with the data given by certain Life Insurance Companies in India. Although mean weight was found to be appreciably higher than the value reported in 1966, based on autopsy data, the mean weight and height are much less than the reference man values adopted by International Commission on Radiological Protection (ICRP) which are based on western man (average weight = 70 kg., average height = 174 cm). (author)

  13. Quality assurance of 3-D conformal radiation therapy for a cooperative group trial - RTOG 3D QA center initial experience

    International Nuclear Information System (INIS)

    Michalski, Jeff M.; Purdy, James A.; Harms, William B.; Bosch, Walter R.; Oehmke, Frederick; Cox, James D.

    1996-01-01

    PURPOSE: 3-D conformal radiation therapy (3DCRT) holds promise in allowing safe escalation of radiation dose to increase the local control of prostate cancer. Prospective evaluation of this new modality requires strict quality assurance (QA). We report the results of QA review on patients receiving 3DCRT for prostate cancer on a cooperative group trial. MATERIALS and METHODS: In 1993 the NCI awarded the ACR/RTOG and nine institutions an RFA grant to study the use of 3DCRT in the treatment of prostate cancer. A phase I/II trial was developed to: a) test the feasibility of conducting 3DCRT radiation dose escalation in a cooperative group setting; b) establish the maximum tolerated radiation dose that can be delivered to the prostate; and c) quantify the normal tissue toxicity rate when using 3DCRT. In order to assure protocol compliance each participating institution was required to implement data exchange capabilities with the RTOG 3D QA center. The QA center reviews at a minimum the first five case from each participating center and spot checks subsequent submissions. For each case review the following parameters are evaluated: 1) target volume delineation, 2) normal structure delineation, 3) CT data quality, 4) field placement, 5) field shaping, and 6) dose distribution. RESULTS: Since the first patient was registered on August 23, 1994, an additional 170 patients have been accrued. Each of the nine original approved institutions has participated and three other centers have recently passed quality assurance bench marks for study participation. Eighty patients have been treated at the first dose level (68.4 Gy minimum PTV dose) and accrual is currently ongoing at the second dose level (73.8 Gy minimum PTV dose). Of the 124 cases that have undergone complete or partial QA review, 30 cases (24%) have had some problems with data exchange. Five of 67 CT scans were not acquired by protocol standards. Target volume delineation required the submitting institution

  14. The Comparison of Stereotactic Body Radiation Therapy (SBRT andIntensity Modulated Radiation Therapy (IMRT for prostate cancer byNCCN risk groups

    Directory of Open Access Journals (Sweden)

    Anthony Ricco

    2016-08-01

    Full Text Available OBJECTIVES: The primary objective of this study is to compare freedom from biochemical failure (FFBF between SBRT and IMRT for patients with organ confined prostate cancer treated between 2007 through 2012 utilizing the 2015 National Comprehensive Cancer Network (NCCN risk stratification guidelines. A secondary objective is to compare our updated toxicity at last follow up compared to pretreatment with respect to bowel, bladder, sexual functioning, and need for invasive procedures between the two groups.METHODS: We retrospectively reviewed 270 consecutive men treated with either SBRT (n=150 or IMRT (120 at a community hospital with two distinct radiation departments and referral patterns. Charts were reviewed for pretreatment and treatment factors including race, age, clinical T stage, initial PSA, Gleason score, use of androgen deprivation therapy (ADT, treatment with SBRT vs. IMRT as well as stratification by 2015 NCCN guidelines. Kaplan Meier (KM methodology was used to estimate freedom from biochemical failure, with statistical comparisons accomplished using log rank tests. Multivariable Cox proportional hazard modeling was used to establish independent factors prognostic of biochemical failure. Descriptive statistics were used to describe toxicity graded by a modified RTOG late radiation morbidity scoring system. RESULTS: Significant prognostic factors in univariate analysis for FFBF included NCCN risk groups (p=0.0032, grade (p=0.019, and PSA (p=0.008. There was no significant difference in FFBF between SBRT vs. IMRT (p=0.46 with 6 year actuarial FFBF of 91.9% for SBRT and 88.9% for IMRT. Multivariable analysis revealed only the NCCN risk stratification to be significant predictor for FFBF (p=0.04. 4 year actuarial FFBF by NCCN risk stratification was 100% very low risk, 100% low risk, 96.5% intermediate risk, 94.5% high risk, and 72.7% very high risk. There were no grade 3 gastrointestinal (GI or genitourinary (GU toxicities for either

  15. Nerve conduction velocity

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003927.htm Nerve conduction velocity To use the sharing features on this page, please enable JavaScript. Nerve conduction velocity (NCV) is a test to see ...

  16. The velocity of sound

    International Nuclear Information System (INIS)

    Beyer, R.T.

    1985-01-01

    The paper reviews the work carried out on the velocity of sound in liquid alkali metals. The experimental methods to determine the velocity measurements are described. Tables are presented of reported data on the velocity of sound in lithium, sodium, potassium, rubidium and caesium. A formula is given for alkali metals, in which the sound velocity is a function of shear viscosity, atomic mass and atomic volume. (U.K.)

  17. Radiation Therapy Did Not Induce Long-Term Changes in Rectal Mucosa: Results From the Randomized Scandinavian Prostate Cancer Group 7 Trial

    Energy Technology Data Exchange (ETDEWEB)

    Slagsvold, Jens Erik, E-mail: Jens.Erik.Slagsvold@stolav.no [Cancer Clinic, St. Olavs Hospital, Trondheim University Hospital, Trondheim (Norway); Viset, Trond [Department of Pathology, St. Olavs Hospital, Trondheim University Hospital, Trondheim (Norway); Wibe, Arne [Institute of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim (Norway); Department of Surgery, St. Olavs Hospital, Trondheim University Hospital, Trondheim (Norway); Kaasa, Stein [Cancer Clinic, St. Olavs Hospital, Trondheim University Hospital, Trondheim (Norway); European Palliative Care Research Center, Department of Cancer Research and Molecular Medicine, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim (Norway); Widmark, Anders [Department of Radiation Sciences, Cancercentrum, Umeå (Sweden); Lund, Jo-Åsmund [Cancer Clinic, St. Olavs Hospital, Trondheim University Hospital, Trondheim (Norway); European Palliative Care Research Center, Department of Cancer Research and Molecular Medicine, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim (Norway)

    2016-07-15

    Purpose: To investigate long-term changes in the rectal mucosa after curative external beam radiation therapy in the treatment of prostate cancer. Methods and Materials: In the Scandinavian Prostate Cancer Group 7 trial, 880 men with locally advanced prostate cancer were randomized to hormonal therapy alone versus hormonal therapy plus radiation therapy to 70 Gy. A subcohort from this trial being randomized at our center (n=178) was invited to a study on late anorectal side effects during 2003-2005, approximately 5 years after treatment, including measuring health-reported quality of life and physician-assessed toxicity score by the Late Effects Normal Tissue Task Force/Subjective, Objective, Management, Analytic (LENT/SOMA) and European Organization for Research and Treatment of Cancer/Radiation Therapy Oncology Group score. Sixty-seven patients had a rectal mucosa biopsy. Sixty-four biopsies were included in the final analysis, of which 33 patients were randomized to hormonal treatment and 31 to hormonal treatment plus radiation therapy. The presence of fibrosis, number of capillaries, and lymphocyte infiltration was then evaluated by light microscopy. Results: The group receiving radiation therapy had significantly higher LENT/SOMA and function/bother scale scores than the group that only received hormonal treatment, but there was no significant difference in the presence of fibrosis, ectasia, number of capillaries in the lamina propria, or lymphocyte infiltration between the groups. Conclusion: Radiation therapy to 70 Gy to the prostate does not induce long-term microscopic mucosal changes in the rectum 5 years after treatment. This is in contrast to the general assumption that structural changes, including fibrosis, seen after radiation therapy include the mucosa. We speculate that the main late effects of radiation therapy on the structure of the rectum are located in the deeper layers of the rectal wall than the mucosa.

  18. ASSESSMENT OF SOCIAL AND PSYCHOLOGICAL CONSEQUENCES OF RADIATION DANGER EXPERIENCE AMONG DIFFERENT AGE GROUPS OF THE POPULATION FROM CONTAMINATED AREAS OF RUSSIA

    Directory of Open Access Journals (Sweden)

    T. A. Marchenko

    2012-01-01

    Full Text Available The results of evaluation of social-psychological consequences of radiation danger experience among different age groups of the population from contaminated areas of Russia (Oryol, Kaluga, Bryansk, Tula areas among whom the unfavorable emotional and personal changes were registered due to subjective features of perception of radiation threat have been represented (“risk” group. Experimental sample of the research consisted of 1 544 people from Russia. One of the main results of this research is establishment of the fact that adverse emotional and personal changes in connection with subjective features of perception of radiation threat were revealed for 53,9% of respondents of advanced age and more than 20% of respondents of middle and young age from contaminated areas of Russia. Among the respondents from contaminated areas of Belarus, about a third surveyed from each age group get to “risk” group.

  19. Pretreatment factors significantly influence quality of life in cancer patients: A Radiation Therapy Oncology Group (RTOG) analysis

    International Nuclear Information System (INIS)

    Movsas, Benjamin; Scott, Charles; Watkins-Bruner, Deborah

    2006-01-01

    Purpose The purpose of this analysis was to assess the impact of pretreatment factors on quality of life (QOL) in cancer patients. Methods and Materials Pretreatment QOL (via Functional Assessment of Cancer Therapy [FACT], version 2) was obtained in 1,428 patients in several prospective Radiation Therapy Oncology Group (RTOG) trials including nonmetastatic head-and-neck (n = 1139), esophageal (n = 174), lung (n = 51), rectal (n = 47), and prostate (n = 17) cancer patients. Clinically meaningful differences between groups were defined as a difference of 1 standard error of measurement (SEM). Results The mean FACT score for all patients was 86 (20.7-112) with SEM of 5.3. Statistically significant differences in QOL were observed based on age, race, Karnofsky Performance Status, marital status, education level, income level, and employment status, but not by gender or primary site. Using the SEM, there were clinically meaningful differences between patients ≤50 years vs. ≥65 years. Hispanics had worse QOL than whites. FACT increased linearly with higher Karnofsky Performance Status and income levels. Married patients (or live-in relationships) had a better QOL than single, divorced, or widowed patients. College graduates had better QOL than those with less education. Conclusion Most pretreatment factors meaningfully influenced baseline QOL. The potentially devastating impact of a cancer diagnosis, particularly in young and minority patients, must be addressed

  20. Blood group typing based on recording the elastic scattering of laser radiation using the method of digital imaging

    International Nuclear Information System (INIS)

    Dolmashkin, A A; Dubrovskii, V A; Zabenkov, I V

    2012-01-01

    The possibility is demonstrated to determine the human blood group by recording the scattering of laser radiation with the help of the digital imaging method. It is experimentally shown that the action of a standing ultrasound wave leads to acceleration of the agglutination reaction of red blood cells, to formation of larger immune complexes of red blood cells, and, as a consequence, to acceleration of their sedimentation. In the absence of agglutination of red blood cells the ultrasound does not enhance the relevant processes. This difference in the results of ultrasound action on the mixture of blood and serum allows a method of blood typing to be offered. Theoretical modelling of the technique of the practical blood typing, carried out on the basis of the elastic light scattering theory, agrees well with the experimental results, which made it possible to plan further improvement of the proposed method. The studies of specific features of sedimentation of red blood cells and their immune complexes were aimed at the optimisation of the sample preparation, i.e., at the search for such experimental conditions that provide the maximal resolution of the method and the device for registering the reaction of red blood cells agglutination. The results of the study may be used in designing the instrumentation for blood group assessment in humans.

  1. Blood group typing based on recording the elastic scattering of laser radiation using the method of digital imaging

    Energy Technology Data Exchange (ETDEWEB)

    Dolmashkin, A A; Dubrovskii, V A; Zabenkov, I V [V.I.Razumovsky Saratov State Medical University, Saratov (Russian Federation)

    2012-05-31

    The possibility is demonstrated to determine the human blood group by recording the scattering of laser radiation with the help of the digital imaging method. It is experimentally shown that the action of a standing ultrasound wave leads to acceleration of the agglutination reaction of red blood cells, to formation of larger immune complexes of red blood cells, and, as a consequence, to acceleration of their sedimentation. In the absence of agglutination of red blood cells the ultrasound does not enhance the relevant processes. This difference in the results of ultrasound action on the mixture of blood and serum allows a method of blood typing to be offered. Theoretical modelling of the technique of the practical blood typing, carried out on the basis of the elastic light scattering theory, agrees well with the experimental results, which made it possible to plan further improvement of the proposed method. The studies of specific features of sedimentation of red blood cells and their immune complexes were aimed at the optimisation of the sample preparation, i.e., at the search for such experimental conditions that provide the maximal resolution of the method and the device for registering the reaction of red blood cells agglutination. The results of the study may be used in designing the instrumentation for blood group assessment in humans.

  2. The radiat ion-epidemiological and cytogenetic study in group of participants of planned working on liquidation consequences Chernobyl accident

    International Nuclear Information System (INIS)

    D'omyina, E.A.

    2005-01-01

    Data of radiation anamnesis (beginning and duration of staying in zone of the Chernobyl radiation accident, kind of fulfilled works) as factors of risk are specific in relation to the basic classes of diseases. Works on burial of atomic pile, deactivation, evacuation and all dates of entrance into the one of radiation injury were recognized as hazardous factors for the development of malignant growth

  3. Patterns of Radiotherapy Practice for Pancreatic Cancer in Japan: Results of the Japanese Radiation Oncology Study Group (JROSG) Survey

    International Nuclear Information System (INIS)

    Ogawa, Kazuhiko; Ito, Yoshinori; Karasawa, Katsuyuki; Ogawa, Yoshihiro; Onishi, Hiroshi; Kazumoto, Tomoko; Shibuya, Keiko; Shibuya, Hitoshi; Okuno, Yoshishige; Nishino, Shigeo; Ogo, Etsuyo; Uchida, Nobue; Karasawa, Kumiko; Nemoto, Kenji; Nishimura, Yasumasa

    2010-01-01

    Purpose: To determine the patterns of radiotherapy practice for pancreatic cancer in Japan. Methods and Materials: A questionnaire-based national survey of radiotherapy for pancreatic cancer treated between 2000 and 2006 was conducted by the Japanese Radiation Oncology Study Group (JROSG). Detailed information on 870 patients from 34 radiation oncology institutions was accumulated. Results: The median age of all patients was 64 years (range, 36-88), and 80.2% of the patients had good performance status. More than 85% of patients had clinical Stage T3-T4 disease, and 68.9% of patients had unresectable disease at diagnosis. Concerning radiotherapy (RT), 49.8% of patients were treated with radical external beam RT (EBRT) (median dose, 50.4 Gy), 44.4% of patients were treated with intraoperative RT (median dose, 25 Gy) with or without EBRT (median dose, 45 Gy), and 5.9% of patients were treated with postoperative radiotherapy (median dose, 50 Gy). The treatment field consisted of the primary tumor (bed) only in 55.6% of the patients. Computed tomography-based treatment planning and conformal RT was used in 93.1% and 83.1% of the patients treated with EBRT, respectively. Chemotherapy was used for 691 patients (79.4%; before RT for 66 patients; during RT for 531; and after RT for 364). Gemcitabine was the most frequently used drug, followed by 5-fluorouracil. Conclusion: This study describes the general patterns of RT practice for pancreatic cancer in Japan. Most patients had advanced unresectable disease, and radical EBRT, as well as intraoperative RT with or without EBRT, was frequently used. Chemotherapy with gemcitabine was commonly used in conjunction with RT during the survey period.

  4. Testing different brain metastasis grading systems in stereotactic radiosurgery: Radiation Therapy Oncology Group's RPA, SIR, BSBM, GPA, and modified RPA.

    Science.gov (United States)

    Serizawa, Toru; Higuchi, Yoshinori; Nagano, Osamu; Hirai, Tatsuo; Ono, Junichi; Saeki, Naokatsu; Miyakawa, Akifumi

    2012-12-01

    The authors conducted validity testing of the 5 major reported indices for radiosurgically treated brain metastases- the original Radiation Therapy Oncology Group's Recursive Partitioning Analysis (RPA), the Score Index for Radiosurgery in Brain Metastases (SIR), the Basic Score for Brain Metastases (BSBM), the Graded Prognostic Assessment (GPA), and the subclassification of RPA Class II proposed by Yamamoto-in nearly 2500 cases treated with Gamma Knife surgery (GKS), focusing on the preservation of neurological function as well as the traditional endpoint of overall survival. The authors analyzed data from 2445 cases treated with GKS by the first author (T.S.), the primary surgeon. The patient group consisted of 1716 patients treated between January 1998 and March 2008 (the Chiba series) and 729 patients treated between April 2008 and December 2011 (the Tokyo series). The interval from the date of GKS until the date of the patient's death (overall survival) and impaired activities of daily living (qualitative survival) were calculated using the Kaplan-Meier method, while the absolute risk for two adjacent classes of each grading system and both hazard ratios and 95% confidence intervals were estimated using the Cox proportional hazards model. For overall survival, there were highly statistically significant differences between each two adjacent patient groups characterized by class or score (all p values RPA appeared to be better than the original RPA and GPA. The modified RPA subclassification, proposed by Yamamoto, is well balanced in scoring simplicity with respect to case number distribution and statistical results for overall survival. However, a new or revised grading system is necessary for predicting qualitative survival and for selecting the optimal treatment for patients with brain metastasis treated by GKS.

  5. Simultaneous adjuvant radiation therapy and chemotherapy in high-risk breast cancer--toxicity and dose modification: a trans-tasman radiation oncology group multi-institution study

    International Nuclear Information System (INIS)

    Denham, James W.; Hamilton, Christopher S.; Christie, David; O'Brien, Maree; Bonaventura, Antonino; Stewart, John F.; Ackland, Stephen P.; Lamb, David S.; Spry, Nigel A.; Dady, Peter; Atkinson, Christopher H.; Wynne, Christopher; Joseph, David J.

    1995-01-01

    Purpose: To establish the toxicity profile of simultaneously administered postoperative radiation therapy and CMF chemotherapy as a prelude to a randomized controlled study addressing the sequencing of the two modalities. Methods and Materials: One hundred and thirty eight breast cancer patients at high risk of locoregional, as well as systemic relapse, who were referred to three centers in Australia and New Zealand were treated with postoperative radiation therapy and chemotherapy simultaneously. Acute toxicity and dose modifications in these patients were compared with 83 patients treated over the same time frame with chemotherapy alone. In a separate study the long-term radiation and surgical effects in 24 patients treated simultaneously with radiation therapy and chemotherapy at Newcastle (Australia) following conservative surgery were compared with 23 matched patients treated at Newcastle with radiation therapy alone. Results: Myelotoxicity was increased in patients treated simultaneously with radiation therapy and chemotherapy. The effect was not great, but may have contributed to chemotherapy dose reductions. Lymphopenia was observed to be the largest factor in total white cell depressions caused by the simultaneous administration of radiation therapy. Postsurgical appearances were found to so dominate long-term treatment effects on the treated breast that the effect of radiation therapy dose and additional chemotherapy was difficult to detect. Conclusion: Studies addressing the sequencing of radiation therapy and chemotherapy will necessarily be large because adverse effects from administering the two modalities simultaneously are not great. The present study has endorsed the importance in future studies of stratification according to the extent and type of surgery and adherence to a single strict policy of chemotherapy dose modification

  6. WE-F-304-01: Overview of the Working Group On Stereotactic Body Radiation Therapy (WGSBRT)

    Energy Technology Data Exchange (ETDEWEB)

    Yorke, E. [Memorial Sloan-Kettering Cancer Center (United States)

    2015-06-15

    Stereotactic Body Radiation Therapy (SBRT) was introduced clinically more than twenty years ago, and many subsequent publications have reported safety and efficacy data. The AAPM Working Group on Biological Effects of Hypofractionated Radiotherapy/SBRT (WGSBRT) extracted published treatment outcomes data from extensive literature searches to summarize and construct tumor control probability (TCP) and normal tissue complication probability (NTCP) models for six anatomical regions: Cranial, Head and Neck, Thoracic, Abdominal, Pelvic, and Spinal. In this session, we present the WGSBRT’s work for cranial sites, and recurrent head and neck cancer. From literature-based data and associated models, guidelines to aid with safe and effective hypofractionated radiotherapy treatment are being determined. Further, the ability of existing and proposed radiobiological models to fit these data is considered as to the ability to distinguish between the linear-quadratic and alternative radiobiological models such as secondary cell death from vascular damage, immunogenic, or bystander effects. Where appropriate, specific model parameters are estimated. As described in “The lessons of QUANTEC,” (1), lack of adequate reporting standards continues to limit the amount of useful quantitative information that can be extracted from peer-reviewed publications. Recommendations regarding reporting standards are considered, to enable such reviews to achieve more complete characterization of clinical outcomes. 1 Jackson A, Marks LB, Bentzen SM, Eisbruch A, Yorke ED, Ten Haken RK, Constine LS, Deasy JO. The lessons of QUANTEC: recommendations for reporting and gathering data on dose-volume dependencies of treatment outcome. Int J Radiat Oncol Biol Phys. 2010 Mar 1;76(3 Suppl):S155–60. Learning Objectives: Describe the techniques, types of cancer and dose schedules used in treating recurrent H&N cancers with SBRT List the radiobiological models that compete with the linear-quadratic model

  7. WE-F-304-01: Overview of the Working Group On Stereotactic Body Radiation Therapy (WGSBRT)

    International Nuclear Information System (INIS)

    Yorke, E.

    2015-01-01

    Stereotactic Body Radiation Therapy (SBRT) was introduced clinically more than twenty years ago, and many subsequent publications have reported safety and efficacy data. The AAPM Working Group on Biological Effects of Hypofractionated Radiotherapy/SBRT (WGSBRT) extracted published treatment outcomes data from extensive literature searches to summarize and construct tumor control probability (TCP) and normal tissue complication probability (NTCP) models for six anatomical regions: Cranial, Head and Neck, Thoracic, Abdominal, Pelvic, and Spinal. In this session, we present the WGSBRT’s work for cranial sites, and recurrent head and neck cancer. From literature-based data and associated models, guidelines to aid with safe and effective hypofractionated radiotherapy treatment are being determined. Further, the ability of existing and proposed radiobiological models to fit these data is considered as to the ability to distinguish between the linear-quadratic and alternative radiobiological models such as secondary cell death from vascular damage, immunogenic, or bystander effects. Where appropriate, specific model parameters are estimated. As described in “The lessons of QUANTEC,” (1), lack of adequate reporting standards continues to limit the amount of useful quantitative information that can be extracted from peer-reviewed publications. Recommendations regarding reporting standards are considered, to enable such reviews to achieve more complete characterization of clinical outcomes. 1 Jackson A, Marks LB, Bentzen SM, Eisbruch A, Yorke ED, Ten Haken RK, Constine LS, Deasy JO. The lessons of QUANTEC: recommendations for reporting and gathering data on dose-volume dependencies of treatment outcome. Int J Radiat Oncol Biol Phys. 2010 Mar 1;76(3 Suppl):S155–60. Learning Objectives: Describe the techniques, types of cancer and dose schedules used in treating recurrent H&N cancers with SBRT List the radiobiological models that compete with the linear-quadratic model

  8. Acute symptoms, not rectally administered sucralfate, predict for late radiation proctitis: longer term follow-up of a phase III trial--Trans-Tasman Radiation Oncology Group.

    Science.gov (United States)

    O'Brien, Peter C; Franklin, C Ian; Poulsen, Michael G; Joseph, David J; Spry, Nigel S; Denham, James W

    2002-10-01

    To assess the potential for sucralfate administered rectally to reduce the risk of late rectal morbidity in patients undergoing nonconformal radiotherapy (RT) for carcinoma of the prostate and to study the variables potentially contributing to late rectal morbidity and particularly to explore the relationship between acute and late toxicity. Eighty-six patients with localized prostate carcinoma were randomized in a double-blind, placebo-controlled study to a daily enema of 3 g of sucralfate in a 15-mL suspension or the same suspension without sucralfate. The enema began the first day of RT and was continued for 2 weeks after treatment completion. The primary end point of the study was acute Radiation Therapy Oncology Group (RTOG)/European Organization for Research and Treatment of Cancer (EORTC) toxicity; however, the patients were followed for an additional 5 years on a 6-month basis. The evaluation included late RTOG/EORTC toxicity and a patient self-assessment questionnaire. With a median follow-up of 5 years, the Kaplan-Meier probability of late Grade 2 RTOG/EORTC toxicity was 12% (95% confidence interval [CI] 2-22%) for placebo and 5% (95% CI 0-12%) for sucralfate (p = 0.26). The probability of late rectal bleeding was 59% (95% CI 45-73%) for placebo and 54% (95% CI 40-68%) for sucralfate. No statistically significant difference was found between the treatment arms for the peak incidence of any of the other patient self-assessment variables. Cox proportional hazards modeling indicated acute RTOG/EORTC toxicity of Grade 2 or greater was associated with a hazard ratio of 2.74 (95% CI 1.31-5.73) for the development of late toxicity of Grade 1 or greater. Substituting the patient self-assessment variables for acute RTOG/EORTC toxicity revealed that rectal pain of a moderate or severe grade during RT was the best predictor of the subsequent development of late toxicity, with a hazard ratio of 3.44 (95% CI 1.68-7). The results of this study do not support the use of

  9. Acute symptoms, not rectally administered sucralfate, predict for late radiation proctitis: longer term follow-up of a phase III trial--Trans-Tasman Radiation Oncology Group

    International Nuclear Information System (INIS)

    O'Brien, Peter C.; Franklin, C. Ian; Poulsen, Michael G.; Joseph, David J.; Spry, Nigel S.; Denham, James W.

    2002-01-01

    Purpose: To assess the potential for sucralfate administered rectally to reduce the risk of late rectal morbidity in patients undergoing nonconformal radiotherapy (RT) for carcinoma of the prostate and to study the variables potentially contributing to late rectal morbidity and particularly to explore the relationship between acute and late toxicity. Methods and Materials: Eighty-six patients with localized prostate carcinoma were randomized in a double-blind, placebo-controlled study to a daily enema of 3 g of sucralfate in a 15-mL suspension or the same suspension without sucralfate. The enema began the first day of RT and was continued for 2 weeks after treatment completion. The primary end point of the study was acute Radiation Therapy Oncology Group (RTOG)/European Organization for Research and Treatment of Cancer (EORTC) toxicity; however, the patients were followed for an additional 5 years on a 6-month basis. The evaluation included late RTOG/EORTC toxicity and a patient self-assessment questionnaire. Results: With a median follow-up of 5 years, the Kaplan-Meier probability of late Grade 2 RTOG/EORTC toxicity was 12% (95% confidence interval [CI] 2-22%) for placebo and 5% (95% CI 0-12%) for sucralfate (p=0.26). The probability of late rectal bleeding was 59% (95% CI 45-73%) for placebo and 54% (95% CI 40-68%) for sucralfate. No statistically significant difference was found between the treatment arms for the peak incidence of any of the other patient self-assessment variables. Cox proportional hazards modeling indicated acute RTOG/EORTC toxicity of Grade 2 or greater was associated with a hazard ratio of 2.74 (95% CI 1.31-5.73) for the development of late toxicity of Grade 1 or greater. Substituting the patient self-assessment variables for acute RTOG/EORTC toxicity revealed that rectal pain of a moderate or severe grade during RT was the best predictor of the subsequent development of late toxicity, with a hazard ratio of 3.44 (95% CI 1.68-7). Conclusion

  10. Older Age Predicts Decreased Metastasis and Prostate Cancer-Specific Death for Men Treated With Radiation Therapy: Meta-Analysis of Radiation Therapy Oncology Group Trials

    Energy Technology Data Exchange (ETDEWEB)

    Hamstra, Daniel A., E-mail: dhamm@umich.edu [University of Michigan, Ann Arbor, Michigan (United States); Bae, Kyounghwa [Radiation Therapy Oncology Group, Philadelphia, Pennsylvania (United States); Pilepich, Miljenko V. [UCLA Medical Center, Los Angeles, California (United States); Hanks, Gerald E. [Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Grignon, David J. [Indiana University-Purdue University Indianapolis, Indiana (United States); McGowan, David G. [Cross Cancer Institute, Edmonton, Alberta (Canada); Roach, Mack [UCSF, San Francisco, California (United States); Lawton, Colleen [Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Lee, R. Jeffrey [Intermountain Medical Center, Salt Lake City, Utah (United States); Sandler, Howard [Cedars-Sinai Medical Center, Los Angeles, California (United States)

    2011-12-01

    Purpose: The impact of age on prostate cancer (PCa) outcome has been controversial; therefore, we analyzed the effect of age on overall survival (OS), distant metastasis, prostate cancer-specific death (PCSD), and nonprostate cancer death (NPCD) on patients with locally advanced PCa. Methods and Materials: Patients who participated in four Radiation Therapy Oncology Group (RTOG) phase III trials, 8531, 8610, 9202, and 9413, were studied. Cox proportional hazards regression was used for OS analysis, and cumulative events analysis with Fine and Gray's regression was used for analyses of metastasis, PCSD, and NPCD. Results: Median follow-up of 4,128 patients with median age of 70 (range, 43-88 years) was 7.3 years. Most patients had high-risk disease: cT3 to cT4 (54%) and Gleason scores (GS) of 7 (45%) and 8 to 10 (27%). Older age ({<=}70 vs. >70 years) predicted for decreased OS (10-year rate, 55% vs. 41%, respectively; p < 0.0001) and increased NPCD (10-year rate, 28% vs. 46%, respectively; p < 0.0001) but decreased metastasis (10-year rate, 27% vs. 20%, respectively; p < 0.0001) and PCSD (10-year rate, 18% vs. 14%, respectively; p < 0.0001). To account for competing risks, outcomes were analyzed in 2-year intervals, and age-dependent differences in metastasis and PCSD persisted, even in the earliest time periods. When adjusted for other covariates, an age of >70 years remained associated with decreased OS (hazard ratio [HR], 1.56 [95% confidence interval [CI], 1.43-1.70] p < 0.0001) but with decreased metastasis (HR, 0.72 [95% CI, 0.63-0.83] p < 0.0001) and PCSD (HR, 0.78 [95% CI, 0.66-0.92] p < 0.0001). Finally, the impact of the duration of androgen deprivation therapy as a function of age was evaluated. Conclusions: These data support less aggressive PCa in older men, independent of other clinical features. While the biological underpinning of this finding remains unknown, stratification by age in future trials appears to be warranted.

  11. Water velocity meter

    Science.gov (United States)

    Roberts, C. W.; Smith, D. L.

    1970-01-01

    Simple, inexpensive drag sphere velocity meter with a zero to 6 ft/sec range measures steady-state flow. When combined with appropriate data acquisition system, it is suited to applications where large numbers of simultaneous measurements are needed for current mapping or velocity profile determination.

  12. Estimation of vector velocity

    DEFF Research Database (Denmark)

    2000-01-01

    Using a pulsed ultrasound field, the two-dimensional velocity vector can be determined with the invention. The method uses a transversally modulated ultrasound field for probing the moving medium under investigation. A modified autocorrelation approach is used in the velocity estimation. The new...

  13. Preliminary Toxicity Analysis of 3-Dimensional Conformal Radiation Therapy Versus Intensity Modulated Radiation Therapy on the High-Dose Arm of the Radiation Therapy Oncology Group 0126 Prostate Cancer Trial

    Energy Technology Data Exchange (ETDEWEB)

    Michalski, Jeff M., E-mail: jmichalski@radonc.wustl.edu [Department of Radiation Oncology Washington University Medical Center, St. Louis, Missouri (United States); Yan, Yan [Radiation Therapy Oncology Group Statistical Center, Philadelphia, Pennsylvania (United States); Watkins-Bruner, Deborah [Emory University School of Nursing, Atlanta, Georgia (United States); Bosch, Walter R. [Department of Radiation Oncology Washington University Medical Center, St. Louis, Missouri (United States); Winter, Kathryn [Radiation Therapy Oncology Group Statistical Center, Philadelphia, Pennsylvania (United States); Galvin, James M. [Department of Radiation Oncology Thomas Jefferson University Hospital, Philadelphia, Pennsylvania (United States); Bahary, Jean-Paul [Department of Radiation Oncology Centre Hospitalier de l' Université de Montréal-Notre Dame, Montreal, QC (Canada); Morton, Gerard C. [Department of Radiation Oncology Toronto-Sunnybrook Regional Cancer Centre, Toronto, ON (Canada); Parliament, Matthew B. [Department of Oncology Cross Cancer Institute, Edmonton, AB (Canada); Sandler, Howard M. [Department of Radiation Oncology Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, California (United States)

    2013-12-01

    Purpose: To give a preliminary report of clinical and treatment factors associated with toxicity in men receiving high-dose radiation therapy (RT) on a phase 3 dose-escalation trial. Methods and Materials: The trial was initiated with 3-dimensional conformal RT (3D-CRT) and amended after 1 year to allow intensity modulated RT (IMRT). Patients treated with 3D-CRT received 55.8 Gy to a planning target volume that included the prostate and seminal vesicles, then 23.4 Gy to prostate only. The IMRT patients were treated to the prostate and proximal seminal vesicles to 79.2 Gy. Common Toxicity Criteria, version 2.0, and Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer late morbidity scores were used for acute and late effects. Results: Of 763 patients randomized to the 79.2-Gy arm of Radiation Therapy Oncology Group 0126 protocol, 748 were eligible and evaluable: 491 and 257 were treated with 3D-CRT and IMRT, respectively. For both bladder and rectum, the volumes receiving 65, 70, and 75 Gy were significantly lower with IMRT (all P<.0001). For grade (G) 2+ acute gastrointestinal/genitourinary (GI/GU) toxicity, both univariate and multivariate analyses showed a statistically significant decrease in G2+ acute collective GI/GU toxicity for IMRT. There were no significant differences with 3D-CRT or IMRT for acute or late G2+ or 3+ GU toxicities. Univariate analysis showed a statistically significant decrease in late G2+ GI toxicity for IMRT (P=.039). On multivariate analysis, IMRT showed a 26% reduction in G2+ late GI toxicity (P=.099). Acute G2+ toxicity was associated with late G3+ toxicity (P=.005). With dose–volume histogram data in the multivariate analysis, RT modality was not significant, whereas white race (P=.001) and rectal V70 ≥15% were associated with G2+ rectal toxicity (P=.034). Conclusions: Intensity modulated RT is associated with a significant reduction in acute G2+ GI/GU toxicity. There is a trend for a

  14. Quality assurance experience with the randomized neuropathic bone pain trial (Trans-Tasman Radiation Oncology Group, 96.05)

    International Nuclear Information System (INIS)

    Roos, Daniel E.; Davis, Sidney R.; Turner, Sandra L.; O'Brien, Peter C.; Spry, Nigel A.; Burmeister, Bryan H.; Hoskin, Peter J.; Ball, David L.

    2003-01-01

    Background and purpose: Trans-Tasman Radiation Oncology Group 96.05 is a prospective randomized controlled trial comparing a single 8 Gy with 20 Gy in five fractions of radiotherapy (RT) for neuropathic pain due to bone metastases. This paper summarizes the quality assurance (QA) activities for the first 234 patients (accrual target 270). Materials and methods: Independent audits to assess compliance with eligibility/exclusion criteria and appropriateness of treatment of the index site were conducted after each cohort of approximately 45 consecutive patients. Reported serious adverse events (SAEs) in the form of cord/cauda equina compression or pathological fracture developing at the index site were investigated and presented in batches to the Independent Data Monitoring Committee. Finally, source data verification of the RT prescription page and treatment records was undertaken for each of the first 234 patients to assess compliance with the protocol. Results: Only one patient was found conclusively not to have genuine neuropathic pain, and there were no detected 'geographical misses' with RT fields. The overall rate of detected infringements for other eligibility criteria over five audits (225 patients) was 8% with a dramatic improvement after the first audit. There has at no stage been a statistically significant difference in SAEs by randomization arm. There was a 22% rate of RT protocol variations involving ten of the 14 contributing centres, although the rate of major dose violations (more than ±10% from protocol dose) was only 6% with no statistically significant difference by randomization arm (P=0.44). Conclusions: QA auditing is an essential but time-consuming component of RT trials, including those assessing palliative endpoints. Our experience confirms that all aspects should commence soon after study activation

  15. Profile of European radiotherapy departments contributing to the EORTC Radiation Oncology Group (ROG) in the 21st century

    International Nuclear Information System (INIS)

    Budiharto, Tom; Musat, Elena; Poortmans, Philip; Hurkmans, Coen; Monti, Angelo; Bar-Deroma, Raquel; Bernstein, Zvi; Tienhoven, Geertjan van; Collette, Laurence; Duclos, Frederic; Davis, Bernard; Aird, Edwin

    2008-01-01

    Purpose: Since 1982, the Radiation Oncology Group of the EORTC (EORTC ROG) has pursued an extensive Quality Assurance (QA) program involving all centres actively participating in its clinical research. The first step is the evaluation of the structure and of the human, technical and organisational resources of the centres, to assess their ability to comply with the current requirements for high-tech radiotherapy (RT). Materials and methods: A facility questionnaire (FQ) was developed in 1989 and adapted over the years to match the evolution of RT techniques. We report on the contents of the current FQ that was completed online by 98 active EORTC ROG member institutions from 19 countries, between December 2005 and October 2007. Results: Similar to the data collected previously, large variations in equipment, staffing and workload between centres remain. Currently only 15 centres still use a Cobalt unit. All centres perform 3D Conformal RT, 79% of them can perform IMRT and 54% are able to deliver stereotactic RT. An external reference dosimetry audit (ERDA) was performed in 88% of the centres for photons and in 73% for electrons, but it was recent (<2 years) in only 74% and 60%, respectively. Conclusion: The use of the FQ helps maintain the minimum quality requirements within the EORTC ROG network: recommendations are made on the basis of the analysis of its results. The present analysis shows that modern RT techniques are widely implemented in the clinic but also that ERDA should be performed more frequently. Repeated assessment using the FQ is warranted to document the future evolution of the EORTC ROG institutions

  16. Pretreatment Quality of Life Predicts for Locoregional Control in Head and Neck Cancer Patients: A Radiation Therapy Oncology Group Analysis

    International Nuclear Information System (INIS)

    Siddiqui, Farzan; Pajak, Thomas F.; Watkins-Bruner, Deborah; Konski, Andre A.; Coyne, James C.; Gwede, Clement K.; Garden, Adam S.; Spencer, Sharon A.; Jones, Christopher; Movsas, Benjamin

    2008-01-01

    Purpose: To analyze the prospectively collected health-related quality-of-life (HRQOL) data from patients enrolled in two Radiation Therapy Oncology Group randomized Phase III head and neck cancer trials (90-03 and 91-11) to assess their value as an independent prognostic factor for locoregional control (LRC) and/or overall survival (OS). Methods and Materials: HRQOL questionnaires, using a validated instrument, the Functional Assessment of Cancer Therapy-Head and Neck (FACT-H and N), version 2, were completed by patients before the start of treatment. OS and LRC were the outcome measures analyzed using a multivariate Cox proportional hazard model. Results: Baseline FACT-H and N data were available for 1,093 patients and missing for 417 patients. No significant difference in outcome was found between the patients with and without baseline FACT-H and N data (p = 0.58). The median follow-up time was 27.2 months for all patients and 49 months for surviving patients. Multivariate analyses were performed for both OS and LRC. Beyond tumor and nodal stage, Karnofsky performance status, primary site, cigarette use, use of concurrent chemotherapy, and altered fractionation schedules, the FACT-H and N score was independently predictive of LRC (but not OS), with p = 0.0038. The functional well-being component of the FACT-H and N predicted most significantly for LRC (p = 0.0004). Conclusions: This study represents, to our knowledge, the largest analysis of HRQOL as a prognostic factor in locally advanced head and neck cancer patients. The results of this study have demonstrated the importance of baseline HRQOL as a significant and independent predictor of LRC in patients with locally advanced head and neck cancer

  17. Clinical Practice Patterns of Radiotherapy in Patients with Hepatocellular Carcinoma: A Korean Radiation Oncology Group Study (KROG 14-07)

    Science.gov (United States)

    Cha, Hyejung; Park, Hee Chul; Yu, Jeong Il; Kim, Tae Hyun; Nam, Taek-Keun; Yoon, Sang Min; Yoon, Won Sup; Kim, Jun Won; Kim, Mi Sook; Jang, Hong Seok; Choi, Youngmin; Kim, Jin Hee; Kay, Chul Seung; Jung, Inkyung; Seong, Jinsil

    2017-01-01

    Purpose The aim of this study was to examine patterns of radiotherapy (RT) in Korean patients with hepatocellular carcinoma (HCC) according to the evolving guideline for HCC established by the Korean Liver Cancer Study Group-National Cancer Center (KLCSG-NCC). Materials and Methods We reviewed 765 patients with HCC who were treated with RT between January 2011 and December 2012 in 12 institutions. Results The median follow-up period was 13.3 months (range, 0.2 to 51.7 months). Compared with previous data between 2004 and 2005, the use of RT as a first treatment has increased (9.0% vs. 40.8%). Increased application of intensity-modulated RT resulted in an increase in radiation dose (fractional dose, 1.8 Gy vs. 2.5 Gy; biologically effective dose, 53.1 Gy10 vs. 56.3 Gy10). Median overall survival was 16.2 months, which is longer than that reported in previous data (12 months). In subgroup analysis, treatments were significantly different according to stage (p < 0.001). Stereotactic body RT was used in patients with early HCC, and most patients with advanced stage were treated with three-dimensional conformal RT. Conclusion Based on the evolving KLCSG-NCC practice guideline for HCC, clinical practice patterns of RT have changed. Although RT is still used mainly in advanced HCC, the number of patients with good performance status who were treated with RT as a first treatment has increased. This change in practice patterns could result in improvement in overall survival. PMID:27338036

  18. Paclitaxel poliglumex, temozolomide, and radiation for newly diagnosed high-grade glioma: a Brown University Oncology Group Study.

    Science.gov (United States)

    Jeyapalan, Suriya; Boxerman, Jerrold; Donahue, John; Goldman, Marc; Kinsella, Timothy; Dipetrillo, Thomas; Evans, Devon; Elinzano, Heinrich; Constantinou, Maria; Stopa, Edward; Puthawala, Yakub; Cielo, Deus; Santaniello, Alyson; Oyelese, Adetokunbo; Mantripragada, Kalyan; Rosati, Kayla; Isdale, Debora; Safran, Howard

    2014-10-01

    Paclitaxel poliglumex (PPX), a drug conjugate that links paclitaxel to poly-L-glutamic acid, is a potent radiation sensitizer. Prior studies in esophageal cancer have demonstrated that PPX (50 mg/m/wk) can be administered with concurrent radiation with acceptable toxicity. The primary objective of this study was to determine the safety of the combination of PPX with temozolomide and concurrent radiation for high-grade gliomas. Eligible patients were required to have WHO grade 3 or 4 gliomas. Patients received weekly PPX (50 mg/m/wk) combined with standard daily temozolomide (75 mg/m) for 6 weeks with concomitant radiation (2.0 Gy, 5 d/wk for a total dose of 60 Gy). Twenty-five patients were enrolled, 17 with glioblastoma and 8 with grade 3 gliomas. Seven of 25 patients had grade 4 myelosuppression. Hematologic toxicity lasted up to 5 months suggesting a drug interaction between PPX and temozolomide. For patients with glioblastoma, the median progression-free survival was 11.5 months and the median overall survival was 18 months. PPX could not be safely combined with temozolomide due to grade 4 hematologic toxicity. However, the favorable progression-free and overall survival suggest that PPX may enhance radiation for glioblastoma. A randomized study of single agent PPX/radiation versus temozolomide/radiation for glioblastoma without MGMT methylation is underway.

  19. Electron nature of chemically active state of spiropyran with nitro group. Dependence of efficiency of radiation colouring of spiropyrans on their structure

    International Nuclear Information System (INIS)

    Kholmanskij, A.S.; Zubkov, A.V.; Dyumaev, K.M.

    1980-01-01

    Using the theory of solvatochromy it is shown that chemically active state of spiropyran with nitro group is its highly polar electron-excitated state. On the basis of the image on the electron nature of chemically active state of spiropyran the dependence of the values of radiation yield of the coloured forms of spiropyrans upon their structure is explained

  20. Intracranial stereotactic positioning systems: Report of the American Association of Physicists in Medicine Radiation Therapy Committee Task Group No. 68

    International Nuclear Information System (INIS)

    Lightstone, A.W.; Benedict, Stanley H.; Bova, Frank J.; Solberg, Timothy D.; Stern, Robin L.

    2005-01-01

    Intracranial stereotactic positioning systems (ISPSs) are used to position patients prior to precise radiation treatment of localized lesions of the brain. Often, the lesion is located in close proximity to critical anatomic features whose functions should be maintained. Many types of ISPSs have been described in the literature and are commercially available. These are briefly reviewed. ISPS systems provide two critical functions. The first is to establish a coordinate system upon which a guided therapy can be applied. The second is to provide a method to reapply the coordinate system to the patient such that the coordinates assigned to the patient's anatomy are identical from application to application. Without limiting this study to any particular approach to ISPSs, this report introduces nomenclature and suggests performance tests to quantify both the stability of the ISPS to map diagnostic data to a coordinate system, as well as the ISPS's ability to be realigned to the patient's anatomy. For users who desire to develop a new ISPS system, it may be necessary for the clinical team to establish the accuracy and precision of each of these functions. For commercially available systems that have demonstrated an acceptable level of accuracy and precision, the clinical team may need to demonstrate local ability to apply the system in a manner consistent with that employed during the published testing. The level of accuracy and precision required of an individual ISPS system is dependent upon the clinical protocol (e.g., fractionation, margin, pathology, etc.). Each clinical team should provide routine quality assurance procedures that are sufficient to support the assumptions of accuracy and precision used during the planning process. The testing of ISPS systems can be grouped into two broad categories, type testing, which occurs prior to general commercialization, and site testing, performed when a commercial system is installed at a clinic. Guidelines to help select

  1. A prospective phase II study of adjuvant postoperative radiation therapy following nodal surgery in malignant melanoma-Trans Tasman Radiation Oncology Group (TROG) Study 96.06

    International Nuclear Information System (INIS)

    Burmeister, Bryan H.; Mark Smithers, B.; Burmeister, Elizabeth; Baumann, Kathryn; Davis, Sidney; Krawitz, Hedley; Johnson, Carol; Spry, Nigel

    2006-01-01

    Background: The role of adjuvant postoperative therapy after resection of localised malignant melanoma involving regional lymph nodes remains controversial. There are no randomised trials that confirm that postoperative radiation conveys a benefit in terms of regional control or survival. Methods: Two hundred and thirty-four patients with melanoma involving lymph nodes were registered on a prospective study to evaluate the effect of postoperative radiation therapy. The regimen consisted of 48 Gy in 20 fractions to the nodal basin using recommended treatment guidelines for each of the major node sites. The primary endpoints were regional in-field relapse and late toxicity. Secondary endpoints were adjacent relapse, distant relapse, overall survival, progression-free survival and time to in-field progression. Results: Adjuvant radiation therapy was well tolerated by all of the patients. As the first site of relapse, regional in-field relapses occurred in 16/234 patients (6.8%). The overall survival was 36% at 5 years. The progression-free survival and regional control rates were 27% and 91%, respectively, at 5 years. Patients with more than 2 nodes involved had a significantly worse outcome in terms of distant relapse, overall and progression-free survival. Conclusion: We believe that adjuvant radiation therapy following nodal surgery could offer a possible benefit in terms of regional control. These results require confirmation in a randomised trial

  2. Risk group dependence of dose-response for biopsy outcome after three-dimensional conformal radiation therapy of prostate cancer

    International Nuclear Information System (INIS)

    Levegruen, Sabine; Jackson, Andrew; Zelefsky, Michael J.; Venkatraman, Ennapadam S.; Skwarchuk, Mark W.; Schlegel, Wolfgang; Fuks, Zvi; Leibel, Steven A.; Ling, C. Clifton

    2002-01-01

    Background and purpose: We fit phenomenological tumor control probability (TCP) models to biopsy outcome after three-dimensional conformal radiation therapy (3D-CRT) of prostate cancer patients to quantify the local dose-response of prostate cancer. Materials and methods: We analyzed the outcome after photon beam 3D-CRT of 103 patients with stage T1c-T3 prostate cancer treated at Memorial Sloan-Kettering Cancer Center (MSKCC) (prescribed target doses between 64.8 and 81 Gy) who had a prostate biopsy performed ≥2.5 years after end of treatment. A univariate logistic regression model based on D mean (mean dose in the planning target volume of each patient) was fit to the whole data set and separately to subgroups characterized by low and high values of tumor-related prognostic factors T-stage ( 6), and pre-treatment prostate-specific antigen (PSA) (≤10 ng/ml vs. >10 ng/ml). In addition, we evaluated five different classifications of the patients into three risk groups, based on all possible combinations of two or three prognostic factors, and fit bivariate logistic regression models with D mean and the risk group category to all patients. Dose-response curves were characterized by TCD 50 , the dose to control 50% of the tumors, and γ 50 , the normalized slope of the dose-response curve at TCD 50 . Results: D mean correlates significantly with biopsy outcome in all patient subgroups and larger values of TCD 50 are observed for patients with unfavorable compared to favorable prognostic factors. For example, TCD 50 for high T-stage patients is 7 Gy higher than for low T-stage patients. For all evaluated risk group definitions, D mean and the risk group category are independent predictors of biopsy outcome in bivariate analysis. The fit values of TCD 50 show a clear separation of 9-10.6 Gy between low and high risk patients. The corresponding dose-response curves are steeper (γ 50 =3.4-5.2) than those obtained when all patients are analyzed together (γ 50 =2

  3. Accuracy and calibration of integrated radiation output indicators in diagnostic radiology: A report of the AAPM Imaging Physics Committee Task Group 190

    International Nuclear Information System (INIS)

    Lin, Pei-Jan P.; Schueler, Beth A.; Balter, Stephen; Strauss, Keith J.; Wunderle, Kevin A.; LaFrance, M. Terry; Kim, Don-Soo; Behrman, Richard H.; Shepard, S. Jeff; Bercha, Ishtiaq H.

    2015-01-01

    Due to the proliferation of disciplines employing fluoroscopy as their primary imaging tool and the prolonged extensive use of fluoroscopy in interventional and cardiovascular angiography procedures, “dose-area-product” (DAP) meters were installed to monitor and record the radiation dose delivered to patients. In some cases, the radiation dose or the output value is calculated, rather than measured, using the pertinent radiological parameters and geometrical information. The AAPM Task Group 190 (TG-190) was established to evaluate the accuracy of the DAP meter in 2008. Since then, the term “DAP-meter” has been revised to air kerma-area product (KAP) meter. The charge of TG 190 (Accuracy and Calibration of Integrated Radiation Output Indicators in Diagnostic Radiology) has also been realigned to investigate the “Accuracy and Calibration of Integrated Radiation Output Indicators” which is reflected in the title of the task group, to include situations where the KAP may be acquired with or without the presence of a physical “meter.” To accomplish this goal, validation test protocols were developed to compare the displayed radiation output value to an external measurement. These test protocols were applied to a number of clinical systems to collect information on the accuracy of dose display values in the field

  4. Accuracy and calibration of integrated radiation output indicators in diagnostic radiology: A report of the AAPM Imaging Physics Committee Task Group 190

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Pei-Jan P., E-mail: Pei-Jan.Lin@vcuhealth.org [Virginia Commonwealth University Medical Center, Richmond, Virginia 23298 (United States); Schueler, Beth A. [Mayo Clinic, Rochester, Minnesota 55905 (United States); Balter, Stephen [Columbia University Medical Center, New York, New York 10032 (United States); Strauss, Keith J. [Children’s Hospital Medical Center, Cincinnati, Ohio 45229 (United States); Wunderle, Kevin A. [Cleveland Clinic Foundation, Cleveland, Ohio 44195 (United States); LaFrance, M. Terry [Baystate Health Systems, Inc., Springfield, Massachusetts 01199 (United States); Kim, Don-Soo [Children’s Hospital Boston, Boston, Massachusetts 02115 (United States); Behrman, Richard H. [Boston University Medical Center, Boston, Massachusetts 02118 (United States); Shepard, S. Jeff [University of Texas MD Anderson Cancer Center, Houston, Texas 77096 (United States); Bercha, Ishtiaq H. [Children’s Hospital Colorado, Aurora, Colorado 80045 (United States)

    2015-12-15

    Due to the proliferation of disciplines employing fluoroscopy as their primary imaging tool and the prolonged extensive use of fluoroscopy in interventional and cardiovascular angiography procedures, “dose-area-product” (DAP) meters were installed to monitor and record the radiation dose delivered to patients. In some cases, the radiation dose or the output value is calculated, rather than measured, using the pertinent radiological parameters and geometrical information. The AAPM Task Group 190 (TG-190) was established to evaluate the accuracy of the DAP meter in 2008. Since then, the term “DAP-meter” has been revised to air kerma-area product (KAP) meter. The charge of TG 190 (Accuracy and Calibration of Integrated Radiation Output Indicators in Diagnostic Radiology) has also been realigned to investigate the “Accuracy and Calibration of Integrated Radiation Output Indicators” which is reflected in the title of the task group, to include situations where the KAP may be acquired with or without the presence of a physical “meter.” To accomplish this goal, validation test protocols were developed to compare the displayed radiation output value to an external measurement. These test protocols were applied to a number of clinical systems to collect information on the accuracy of dose display values in the field.

  5. Current status of biological indicators to detect and quantify previous exposures to radiation. Biological Indicators Working Group

    International Nuclear Information System (INIS)

    Lushbaugh, C.; Eisele, G.; Burr, W. Jr.; Hubner, K.; Wachholz, B.

    1991-01-01

    Hematologic changes following whole-body exposure to gamma or x-ray radiation have been used to estimate dose. The usefulness of this biological indicator is limited because of the recovery of these cells with time, thus making it unsuitable for estimation of dose years after exposure. The same is true for spermatogenic indicators; recovery and restoration of sperm numbers and fertility makes this biological indicator impractical for assessing radiation dose decades after radiation exposure. As noted in the text of the report, immunological concepts are in a state of rapid development, and it is possible that improved methods for applying immunologic procedures as biological indicators of radiation may be developed in the future. However, at the time, immunological indicators are not useful, even in an early time period, for quantitating radiation dose after total-body irradiation. A semiquantitative effect is observable in the early phase after total-body irradiation over a period of days to weeks, but there is little data available to indicate whether any of the immunological parameters can be indicative of a dose when the test is applied several years after radiation exposure. More detailed information regarding immunological indicators for estimating irradiation dose has been summarized elsewhere (Wasserman 1986). There is good agreement that ionizing radiation causes biochemical changes in the body; however, attempts to apply these changes to provide a reliable biological dosimetry system have not been particularly successful. The status of this research has been summarized by Gerber (1986). One of the difficulties has been the problem of establishing clear dose-effect relationships in humans. The lack of specificity in the response for radiation is another problem

  6. IAEA advisory group meeting on nuclear data for radiation damage assessment and related safety aspects, Vienna, 12-16 October 1981

    International Nuclear Information System (INIS)

    Kocherov, N.

    1982-01-01

    This Advisory Group Meeting on Nuclear Data for Radiation Damage Assessment and Related Safety Aspects was convened by the IAEA Nuclear Data Section, at IAEA Headquarters in Vienna, Austria, from 12-16 October 1981. The meeting was attended by 34 participants from 15 countries and 2 international organizations. The main objective of the meeting was to review the requirements for and the status of nuclear data needed for radiation damage estimates in reactor structural materials and related reactor safety aspects, and to develop recommendations to the Nuclear Data Section of the IAEA for its future activities in this field. (author)

  7. Australian and New Zealand Faculty of Radiation Oncology Genito-Urinary Group: 2011 consensus guidelines for curative radiotherapy for urothelial carcinoma of the bladder

    International Nuclear Information System (INIS)

    Hindson, Benjamin R.; Turner, Sandra L.; Millar, Jeremy L.

    2012-01-01

    Curative radiotherapy, with or without concurrent chemotherapy, is recognized as a standard treatment option for muscle-invasive bladder cancer. It is commonly used for two distinct groups of patients: either for those medically unfit for surgery, or as part of a 'bladder preserving' management plan incorporating the possibility of salvage cystectomy. However, in both situations, the approach to radiotherapy varies widely around the world. The Australian and New Zealand Faculty of Radiation Oncology Genito-Urinary Group recognised a need to develop consistent, evidence-based guidelines for patient selection and radiotherapy technique in the delivery of curative radiotherapy. Following a workshop convened in May 2009, a working party collated opinions and conducted a wide literature appraisal linking each recommendation with the best available evidence. This process was subject to ongoing re-presentation to the Faculty of Radiation Oncology Genito-Urinary Group members prior to final endorsement. These Guidelines include patient selection, radiation target delineation, dose and fractionation schedules, normal tissue constraints and investigational techniques. Particular emphasis is given to the rationale for the target volumes described. These Guidelines provide a consensus-based framework for the delivery of curative radiotherapy for muscle-invasive bladder cancer. Widespread input from radiation oncologists treating bladder cancer ensures that these techniques are feasible in practice. We recommend these Guidelines be adopted widely in order to encourage a uniformly high standard of radiotherapy in this setting, and to allow for better comparison of outcomes.

  8. Velocity Feedback Experiments

    Directory of Open Access Journals (Sweden)

    Chiu Choi

    2017-02-01

    Full Text Available Transient response such as ringing in a control system can be reduced or removed by velocity feedback. It is a useful control technique that should be covered in the relevant engineering laboratory courses. We developed velocity feedback experiments using two different low cost technologies, viz., operational amplifiers and microcontrollers. These experiments can be easily integrated into laboratory courses on feedback control systems or microcontroller applications. The intent of developing these experiments was to illustrate the ringing problem and to offer effective, low cost solutions for removing such problem. In this paper the pedagogical approach for these velocity feedback experiments was described. The advantages and disadvantages of the two different implementation of velocity feedback were discussed also.

  9. The critical ionization velocity

    International Nuclear Information System (INIS)

    Raadu, M.A.

    1980-06-01

    The critical ionization velocity effect was first proposed in the context of space plasmas. This effect occurs for a neutral gas moving through a magnetized plasma and leads to rapid ionization and braking of the relative motion when a marginal velocity, 'the critical velocity', is exceeded. Laboratory experiments have clearly established the significance of the critical velocity and have provided evidence for an underlying mechanism which relies on the combined action of electron impact ionization and a collective plasma interaction heating electrons. There is experimental support for such a mechanism based on the heating of electrons by the modified two-stream instability as part of a feedback process. Several applications to space plasmas have been proposed and the possibility of space experiments has been discussed. (author)

  10. High Velocity Gas Gun

    Science.gov (United States)

    1988-01-01

    A video tape related to orbital debris research is presented. The video tape covers the process of loading a High Velocity Gas Gun and firing it into a mounted metal plate. The process is then repeated in slow motion.

  11. Report by the work-group on radiation protection in interventional radiology. Recommendations related to the improvement of radiation protection in interventional radiology

    International Nuclear Information System (INIS)

    2010-01-01

    This report aims at proposing recommendations for the improvement of the quality of radiation protection of workers and patients in the field of interventional radiology. These recommendations concern the training of health personnel, the application of the optimization principle to health professionals and patients, dosimetry and the definition of diagnosis reference levels. More particularly, these recommendations concern professions involved in interventional radiology, and take into account the experience of other European Union State members and recommendations made by the IAEA. The authors analyze the equipment, radiological actions, procedures and doses, practitioners, equipment used for radio-guided interventions. They discuss doses received by patients, patient monitoring and radio-induced lesions. Then, they address the role and training of the different interveners in radiation protection, the equipment maintenance issue, and personnel dosimetry and protection

  12. A Phase II Study of Intensity Modulated Radiation Therapy to the Pelvis for Postoperative Patients With Endometrial Carcinoma: Radiation Therapy Oncology Group Trial 0418

    Energy Technology Data Exchange (ETDEWEB)

    Jhingran, Anuja, E-mail: ajhingra@mdanderson.org [University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Winter, Kathryn [RTOG Statistical Center, Philadelphia, Pennsylvania (United States); Portelance, Lorraine [University of Miami, Miami, Florida (United States); Miller, Brigitte [Carolinas Medical Center North East, Concord, North Carolina (United States); Salehpour, Mohammad [University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Gaur, Rakesh [St. Luke' s Hospital, Kansas City, Missouri (United States); Souhami, Luis [McGill University Health Centre, Montreal, Quebec (Canada); Small, William [Robert H. Lurie Comprehensive Cancer Center of Northwestern University, Chicago, Illionis (United States); Berk, Lawrence [H. Lee Moffitt Cancer Center, Tampa, Florida (United States); Gaffney, David [Huntsman Cancer Hospital, Salt Lake City, Utah (United States)

    2012-09-01

    Purpose: To determine the feasibility of pelvic intensity modulated radiation therapy (IMRT) for patients with endometrial cancer in a multi-institutional setting and to determine whether this treatment is associated with fewer short-term bowel adverse events than standard radiation therapy. Methods: Patients with adenocarcinoma of the endometrium treated with pelvic radiation therapy alone were eligible. Guidelines for target definition and delineation, dose prescription, and dose-volume constraints for the targets and critical normal structures were detailed in the study protocol and a web-based atlas. Results: Fifty-eight patients were accrued by 25 institutions; 43 were eligible for analysis. Forty-two patients (98%) had an acceptable IMRT plan; 1 had an unacceptable variation from the prescribed dose to the nodal planning target volume. The proportions of cases in which doses to critical normal structures exceeded protocol criteria were as follows: bladder, 67%; rectum, 76%; bowel, 17%; and femoral heads, 33%. Twelve patients (28%) developed grade {>=}2 short-term bowel adverse events. Conclusions: Pelvic IMRT for endometrial cancer is feasible across multiple institutions with use of a detailed protocol and centralized quality assurance (QA). For future trials, contouring of vaginal and nodal tissue will need continued monitoring with good QA and better definitions will be needed for organs at risk.

  13. Interobserver Variability in Target Definition for Hepatocellular Carcinoma With and Without Portal Vein Thrombus: Radiation Therapy Oncology Group Consensus Guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Theodore S., E-mail: tshong1@mgh.harvard.edu [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts (United States); Bosch, Walter R. [Department of Radiation Oncology, Washington University in St. Louis School of Medicine, St. Louis, Missouri (United States); Krishnan, Sunil [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Kim, Tae K. [Department of Medical Imaging, University Health Network, Mount Sinai Hospital and Women' s College Hospital, University of Toronto, Toronto, Ontario (Canada); Mamon, Harvey J. [Department of Radiation Oncology, Dana-Farber Cancer Institute/Brigham and Women' s Hospital and Harvard Medical School, Boston, Massachusetts (United States); Shyn, Paul [Department of Radiology, Brigham and Women' s Hospital and Harvard Medical School, Boston, Massachusetts (United States); Ben-Josef, Edgar [Department of Radiation Oncology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania (United States); Seong, Jinsil [Department of Radiation Oncology, Yonsei University Medical College, Seoul (Korea, Republic of); Haddock, Michael G. [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Cheng, Jason C. [Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan (China); Feng, Mary U. [Department of Radiation Oncology, University of Michigan Health System, Ann Arbor, Michigan (United States); Stephans, Kevin L. [Department of Radiation Oncology, Cleveland Clinic, Cleveland, Ohio (United States); Roberge, David [Department of Radiation Oncology, Montreal General Hospital/McGill University Health Centre, Montreal, Quebec (Canada); Crane, Christopher [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); and others

    2014-07-15

    Purpose: Defining hepatocellular carcinoma (HCC) gross tumor volume (GTV) requires multimodal imaging, acquired in different perfusion phases. The purposes of this study were to evaluate the variability in contouring and to establish guidelines and educational recommendations for reproducible HCC contouring for treatment planning. Methods and Materials: Anonymous, multiphasic planning computed tomography scans obtained from 3 patients with HCC were identified and distributed to a panel of 11 gastrointestinal radiation oncologists. Panelists were asked the number of HCC cases they treated in the past year. Case 1 had no vascular involvement, case 2 had extensive portal vein involvement, and case 3 had minor branched portal vein involvement. The agreement between the contoured total GTVs (primary + vascular GTV) was assessed using the generalized kappa statistic. Agreement interpretation was evaluated using Landis and Koch's interpretation of strength of agreement. The S95 contour, defined using the simultaneous truth and performance level estimation (STAPLE) algorithm consensus at the 95% confidence level, was created for each case. Results: Of the 11 panelists, 3 had treated >25 cases in the past year, 2 had treated 10 to 25 cases, 2 had treated 5 to 10 cases, 2 had treated 1 to 5 cases, 1 had treated 0 cases, and 1 did not respond. Near perfect agreement was seen for case 1, and substantial agreement was seen for cases 2 and 3. For case 2, there was significant heterogeneity in the volume identified as tumor thrombus (range 0.58-40.45 cc). For case 3, 2 panelists did not include the branched portal vein thrombus, and 7 panelists contoured thrombus separately from the primary tumor, also showing significant heterogeneity in volume of tumor thrombus (range 4.52-34.27 cc). Conclusions: In a group of experts, excellent agreement was seen in contouring total GTV. Heterogeneity exists in the definition of portal vein thrombus that may impact treatment

  14. Solar Electromagnetic Radiation Study for Solar Cycle 22: Solar Ultraviolet Irradiance, 120 to 300 NM: Report of Working Groups 2 and 3 of SOLERS 22

    Science.gov (United States)

    Rottman, G. J.; Cebula, R. P.; Gillotay, D.; Simon, P. A.

    1996-01-01

    This report summarizes the activities of Working Group 2 and Working Group 3 of the SOLax Electromagnetic Radiation Study for Solar Cycle 22 (SOLERS22) Program. The international (SOLERS22) is Project 1.2 of the Solar-Terrestrial Energy Program (STEP) sponsored by SCOSTEP, a committee of the International Council of Scientific Unions). SOLERS22 is comprised of five Working Groups, each concentrating on a specific wave-length range: WG-1 - visible and infrared, WG-2 - mid-ultraviolet (200 solar irradiance values in the specified wavelength ranges, 2) consider the evolving solar structures as the cause of temporal variations, and 3) understand the underlying physical processes driving these changes.

  15. Progress report of the Radiation Technology and Industrial Applications Section, Isotope Group for the period ending August 1977

    International Nuclear Information System (INIS)

    Naik, A.D.; Roy, A.N.; Majali, A.B.

    1977-01-01

    The activities of the Radiation Technology and Industrial Applications Section of the Bhabha Atomic Research Centre, Bombay, for the period ending August 1977 are reported. Major highlights are: (1) completion of studies and design engineering for an economic scale cobalt-60 based irradiator for the radiation sterilisation of medical products, (2) taking up the work of setting up the cobalt-60 irradiation facilities for sources up to 300,000 Ci level, (3) development of radiation processed wood-polymer composite and practical demonstration of its superiority for application in industries - a cobalt-60 facility specifically for this purpose is being installed, (4) development of a commercially viable design of a smoke alarm system based on radioisotopes and (5) production and supply of irradiation units such as gamma chambers, radiography cameras, etc. (M.G.B.)

  16. GRAVITATIONAL RADIATION

    Directory of Open Access Journals (Sweden)

    Metin SALTIK

    1996-03-01

    Full Text Available According to classical electromagnetic theory, an accelerated charge or system of charges radiates electromagnetic waves. In a radio transmitter antenna charges are accelerated along the antenna and release electromagnetic waves, which is radiated at the velocity of light in the surrounding medium. All of the radio transmitters work on this principle today. In this study an analogy is established between the principles by which accelerated charge systems markes radiation and the accelerated mass system, and the systems cousing gravitational radiation are investigated.

  17. Synchrotron radiation

    International Nuclear Information System (INIS)

    Farge, Y.

    1982-01-01

    Synchrotron radiation is produced by electrons accelerated near the velocity of light in storage rings, which are used for high energy Physics experiments. The radiation light exhibits a wide spread continuous spectrum ranging from 01 nanometre to radiofrequency. This radiation is characterized by high power (several kilowatts) and intense brightness. The paper recalls the emission laws and the distinctive properties of the radiation, and gives some of the numerous applications in research, such as molecular spectroscopy, X ray diffraction by heavy proteins and X ray microlithography in LVSI circuit making [fr

  18. Superluminal velocity of photons in a gravitational background

    International Nuclear Information System (INIS)

    Khriplovich, I.B.

    1994-01-01

    The influence of radiative corrections on the photon propagation in a gravitational background is investigated without the low-frequency assumption. The conclusion is made in this way that the velocity of light can exceed unity. 7 refs

  19. Interagency task force on the health effects of ionizing radiation: report of the work group on science

    International Nuclear Information System (INIS)

    1979-06-01

    Much of our present uncertainty about the biologic effects of ionizing radiation centers on effects at low-dose levels. One indication of this uncertainty is the current controversy surrounding several recent epidemiologic analyses which suggest that low-dose radiation exposure may be more effective in causing cancer than had previously been predicted. Populations studied in these recent analyses have included radiation workers at nuclear facilities, including nuclear shipyards, and persons receiving medical diagnostic x-rays, situations in which exposure levels are known to be in the low range. Also of concern have been recent studies involving persons present at atmospheric nuclear bomb tests or exposed to fallout from such testing. Exposure levels in these latter 2 settings, while possibly low, as yet are somewhat uncertain. The implications of these various sets of data, if confirmed, may be far-reaching with respect to occupational standards and medical practices. Their interpretation at present, therefore, is a matter of considerable scientific and public concern. In response to this concern, the White House in May, 1978, requested that the Secretary of HEW coordinate formulating an interagency program to assess current knowledge regarding the health effects of ionizing radiation, and to address concerns about care and benefits available to exposed persons, public health education, and measures to reduce dose levels

  20. Mechanisms of radiation in a bat group from the genus Pipistrellus inferred by phylogeography, demography and population genetics

    Czech Academy of Sciences Publication Activity Database

    Hulva, P.; Fornůsková, Alena; Chudárková, A.; Evin, A.; Allegrini, B.; Benda, P.; Bryja, Josef

    2010-01-01

    Roč. 19, č. 24 (2010), s. 5417-5431 ISSN 0962-1083 R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60930519 Keywords : hybrid speciation * introgression * Mediterranean * microsatellites * mitochondrial DNA * phylogeography * bats * radiation Subject RIV: EG - Zoology Impact factor: 6.457, year: 2010

  1. Exploring the interactions and binding sites between Cd and functional groups in soil using two-dimensional correlation spectroscopy and synchrotron radiation based spectromicroscopies

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Fusheng [Jiangsu Provincial Key Lab for Organic Solid Waste Utilization and National Engineering Research Center for Organic-Based Fertilizers, College of Resources & Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Department of Soil Science, North Carolina State University, Raleigh, NC 27695 (United States); Polizzotto, Matthew L. [Department of Soil Science, North Carolina State University, Raleigh, NC 27695 (United States); Guan, Dongxing [Key Laboratory of Surficial Geochemistry, Ministry of Education, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210026 (China); Wu, Jun [College of Environment, Zhejiang University of Technology, Hangzhou 310014 (China); Shen, Qirong; Ran, Wei [Jiangsu Provincial Key Lab for Organic Solid Waste Utilization and National Engineering Research Center for Organic-Based Fertilizers, College of Resources & Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Wang, Boren [Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081 (China); Yu, Guanghui, E-mail: yuguanghui@njau.edu.cn [Jiangsu Provincial Key Lab for Organic Solid Waste Utilization and National Engineering Research Center for Organic-Based Fertilizers, College of Resources & Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China)

    2017-03-15

    Highlights: • The interactions and binding between Cd and functional groups are essential for their fates. • Two-dimensional correlation spectroscopy can identify Cd binding to functional groups in soils. • Synchrotron radiation based spectromicroscopy shows the micro-scale distribution of Cd in soils. • Soil functional groups controlling Cd binding can be modified by fertilization treatments. - Abstract: Understanding how heavy metals bind and interact in soils is essential for predicting their distributions, reactions and fates in the environment. Here we propose a novel strategy, i.e., combining two-dimensional correlation spectroscopy (2D COS) and synchrotron radiation based spectromicroscopies, for identifying heavy metal binding to functional groups in soils. The results showed that although long-term (23 yrs) organic fertilization treatment caused the accumulation of Cd (over 3 times) in soils when compared to no fertilization and chemical fertilization treatments, it significantly (p < 0.05) reduced the Cd concentration in wheat grain. The 2D COS analyses demonstrated that soil functional groups controlling Cd binding were modified by fertilization treatments, providing implications for the reduced bioavailability of heavy metals in organic fertilized soils. Furthermore, correlative micro X-ray fluorescence spectromicroscopy, electron probe micro-analyzer mapping, and synchrotron-radiation-based FTIR spectromicroscopy analysis showed that Cd, minerals, and organic functional groups were heterogeneously distributed at the micro-scale in soil colloids. Only minerals, rather than organic groups, had a similar distribution pattern with Cd. Together, this strategy has a potential to explore the interactions and binding sites among heavy metals, minerals and organic components in soil.

  2. On an illusion of superluminal velocities produced by gravitational lenses

    International Nuclear Information System (INIS)

    Ingel, L.Kh.

    1981-01-01

    It is noted that gravitational lenses, by focusing the radiation of an object, increase the angle which it subtends. This in turn produces the illusion of an increase in velocities at right angles to the line of sight. Preliminary estimates are made which indicate a rather high probability of strong distortion of the observed velocities

  3. Modified circular velocity law

    Science.gov (United States)

    Djeghloul, Nazim

    2018-05-01

    A modified circular velocity law is presented for a test body orbiting around a spherically symmetric mass. This law exhibits a distance scale parameter and allows to recover both usual Newtonian behaviour for lower distances and a constant velocity limit at large scale. Application to the Galaxy predicts the known behaviour and also leads to a galactic mass in accordance with the measured visible stellar mass so that additional dark matter inside the Galaxy can be avoided. It is also shown that this circular velocity law can be embedded in a geometrical description of spacetime within the standard general relativity framework upon relaxing the usual asymptotic flatness condition. This formulation allows to redefine the introduced Newtonian scale limit in term of the central mass exclusively. Moreover, a satisfactory answer to the galactic escape speed problem can be provided indicating the possibility that one can also get rid of dark matter halo outside the Galaxy.

  4. Guidelines for target volume definition in post-operative radiotherapy for prostate cancer, on behalf of the EORTC Radiation Oncology Group

    International Nuclear Information System (INIS)

    Poortmans, Philip; Bossi, Alberto; Vandeputte, Katia; Bosset, Mathieu; Miralbell, Raymond; Maingon, Philippe; Boehmer, Dirk; Budiharto, Tom; Symon, Zvi; Bergh, Alfons C.M. van den; Scrase, Christopher; Poppel, Hendrik van; Bolla, Michel

    2007-01-01

    The appropriate application of 3-D conformal radiotherapy, intensity modulated radiotherapy or image guided radiotherapy for patients undergoing post-operative radiotherapy for prostate cancer requires a standardisation of the target volume definition and delineation as well as standardisation of the clinical quality assurance procedures. Recommendations for this are presented on behalf of the European Organisation for Research and Treatment of Cancer (EORTC) Radiation Oncology Group and in addition to the already published guidelines for radiotherapy as the primary treatment

  5. OPTIMAL SURGICAL MANAGEMENT OF HIGH VELOCITY POSTERIOR TIBIAL PLATEAU FRACTURE SUBLUXATIONS (DUPARC, REVISED CLASSIFICATION, GROUP – V: POSTERO - MEDIAL FRACTURE BY DIRECT, DORSAL APPROACH – A CHANGING TREND: A PROSPECTIVE STUDY

    Directory of Open Access Journals (Sweden)

    Pardhasaradhi

    2015-10-01

    series of 15 patients with complex tibial plateau injuries with associated posterior shear fractures. MATERIALS AND METHODS : This prospective study included 15 cases of patients with mean age of 30 years ( Age range 20 to 40 yr who sustained high velocity posterior tibial plateau fracture - subluxations with or without associated Bicondylar fractures ( Duparc, revised classification, Group – V: Postero - medial fracture and its associations. Surgical management includes by direct, dorsal approach and stabilisation with buttress plating and or also postero medial and or antero lateral approach as needed. The patients were followed up at six week, three month, six month and one year postoperatively and assessed using Oxford Knee Score and Lyshom Score. RESULTS:The mean OKS score was 40 (range 36 to 44 at the end of one year. The main clinical measures were early post - operative non weight bearing ROM, post - operative complication & functional outcome. The time to full weight bearing, t he rate of post - operative complications & functional outcome was significantly better as evident by over 94 % showing good to excellent OKS and Lyshom scores. CONCLUSION : Fractures of the postero - medial tibial plateau are challenging to treat, owing to the ir complexity and unfamiliar surgical approach. Several recent anatomic and biomechanical studies have shown that a locked plate placed from the lateral side of the proximal tibia does not capture and stabilise a typical posteromedial fragment. A direct po sterior (Medial Gastrocnemius or posterior medial approach for these unstable posterior medial tibial plateau subluxations (which are otherwise irreducible by conventional approaches and antiglide plate are usually needed to reduce the fractures anatomic ally, achieving absolute stability and mobilise early NWB, ROM of the knee joint to optimize the functional outcomes and minimise the complications, without the need for revision surgery

  6. [Effect of UV-radiation on the level of ascorbic acid, SH-groups, and activity of glutathione reductase in the eye lens].

    Science.gov (United States)

    Byshneva, L N; Senchuk, V V

    2002-01-01

    The effect of UV radiation in vitro on the level of ascorbate, SH-groups and glutathione reductase activity in the soluble fraction of bovine eye lens was studied. UV-Irradiation increased NADPH-oxidoreductase activity, the level of ascorbate oxidation and decreased the content of SH-groups and activity of glutathione reductase. Significant activation of the NADPH-oxidoreductase activity in the presence of ascorbate and Cu2+ was observed after UV-irradiation. It is suggested that ascorbate may play an important role in the UV-induced lens pathology.

  7. Interagency task force on the health effects of ionizing radiation: report of the work group on records and privacy

    International Nuclear Information System (INIS)

    1979-06-01

    Research scientists studying the health effects of ionizing radiation have expressed the view that their work is sometimes impeded by legal restrictions on access to necessary records. In light of the critical importance of scientifically sound, efficient, and timely epidemiological research to resolve the difficult issues raised by the President's memorandum, the Task Force determined to inquire into the extent of this problem, and to ascertain whether new legislation or regulation was needed to eliminate serious roadblocks

  8. Therapeutic radiation at a young age is linked to secondary thyroid cancer. The Late Effects Study Group

    International Nuclear Information System (INIS)

    Tucker, M.A.; Jones, P.H.; Boice, J.D. Jr.; Robison, L.L.; Stone, B.J.; Stovall, M.; Jenkin, R.D.; Lubin, J.H.; Baum, E.S.; Siegel, S.E.

    1991-01-01

    We estimated the risk of thyroid cancer among 9170 patients who had survived 2 or more years after the diagnosis of a cancer in childhood. As compared with the general population, patients had a 53-fold increased risk (95% confidence interval, 34-80). Risk increased significantly with time since treatment for the initial cancer (P = 0.03). Detailed treatment data were obtained for 23 cases and 89 matched controls from the childhood cancer cohort. Sixty-eight % of the thyroid cancers arose within the field of radiation. Radiation doses to the thyroid of greater than 200 cGy were associated with a 13-fold increased risk (95% confidence interval, 1.7-104). The risk of thyroid cancer rose with increasing dose (P less than 0.001), but this was derived almost entirely from the increase from less than 200 to greater than 200 cGy. The risk of thyroid cancer did not decrease, however, at radiation doses as high as 6000 cGy

  9. Sound radiation quantities arising from a resilient circular radiator

    NARCIS (Netherlands)

    Aarts, R.M.; Janssen, A.J.E.M.

    2009-01-01

    Power series expansions in ka are derived for the pressure at the edge of a radiator, the reaction force on the radiator, and the total radiated power arising from a harmonically excited, resilient, flat, circular radiator of radius a in an infinite baffle. The velocity profiles on the radiator are

  10. The Prescribed Velocity Method

    DEFF Research Database (Denmark)

    Nielsen, Peter Vilhelm

    The- velocity level in a room ventilated by jet ventilation is strongly influenced by the supply conditions. The momentum flow in the supply jets controls the air movement in the room and, therefore, it is very important that the inlet conditions and the numerical method can generate a satisfactory...

  11. Multidisc neutron velocity selector

    International Nuclear Information System (INIS)

    Rosta, L.; Zsigmond, Gy.; Farago, B.; Mezei, F.; Ban, K.; Perendi, J.

    1987-12-01

    The prototype of a velocity selector for neutron monochromatization in the 4-20 A wavelength range is presented. The theoretical background of the multidisc rotor system is given together with a description of the mechanical construction and electronic driving system. The first tests and neutron measurements prove easy handling and excellent parameters. (author) 6 refs.; 7 figs.; 2 tabs

  12. Individualized Prediction of Overall Survival After Postoperative Radiation Therapy in Patients With Early-Stage Cervical Cancer: A Korean Radiation Oncology Group Study (KROG 13-03)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun Jin [Department of Radiation Oncology, Asan Medical Center, University of Ulsan, College of Medicine, Seoul (Korea, Republic of); Han, Seungbong [Department of Clinical Epidemiology and Biostatistics, Asan Medical Center, University of Ulsan, College of Medicine, Seoul (Korea, Republic of); Kim, Young Seok, E-mail: ysk@amc.seoul.kr [Department of Radiation Oncology, Asan Medical Center, University of Ulsan, College of Medicine, Seoul (Korea, Republic of); Nam, Joo-Hyun [Department of Obstetrics and Gynecology, Asan Medical Center, University of Ulsan, College of Medicine, Seoul (Korea, Republic of); Kim, Hak Jae [Department of Radiation Oncology, Seoul National University Hospital, Seoul (Korea, Republic of); Kim, Jae Weon [Department of Obstetrics and Gynecology, Seoul National University Hospital, Seoul (Korea, Republic of); Park, Won [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Byoung-Gie [Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Jin Hee [Department of Radiation Oncology, Dongsan Medical Center, Keimyung University School of Medicine, Daegu (Korea, Republic of); Cha, Soon Do [Department of Obstetrics and Gynecology, Dongsan Medical Center, Keimyung University School of Medicine, Daegu (Korea, Republic of); Kim, Juree [Department of Radiation Oncology, Cheil General Hospital and Women' s Healthcare Center, Kwandong University, College of Medicine, Seoul (Korea, Republic of); Lee, Ki-Heon [Department of Obstetrics and Gynecology, Cheil General Hospital and Women' s Healthcare Center, Kwandong University, College of Medicine, Seoul (Korea, Republic of); Yoon, Mee Sun [Department of Radiation Oncology, Chonnam National University Hwasun Hospital, Chonnam National University Medical School, Jeollanam-do (Korea, Republic of); and others

    2013-11-15

    Purpose: A nomogram is a predictive statistical model that generates the continuous probability of a clinical event such as death or recurrence. The aim of the study was to construct a nomogram to predict 5-year overall survival after postoperative radiation therapy for stage IB to IIA cervical cancer. Methods and Materials: The clinical data from 1702 patients with early-stage cervical cancer, treated at 10 participating hospitals from 1990 to 2011, were reviewed to develop a prediction nomogram based on the Cox proportional hazards model. Demographic, clinical, and pathologic variables were included and analyzed to formulate the nomogram. The discrimination and calibration power of the model was measured using a concordance index (c-index) and calibration curve. Results: The median follow-up period for surviving patients was 75.6 months, and the 5-year overall survival probability was 87.1%. The final model was constructed using the following variables: age, number of positive pelvic lymph nodes, parametrial invasion, lymphovascular invasion, and the use of concurrent chemotherapy. The nomogram predicted the 5-year overall survival with a c-index of 0.69, which was superior to the predictive power of the International Federation of Gynecology and Obstetrics (FIGO) staging system (c-index of 0.54). Conclusions: A survival-predicting nomogram that offers an accurate level of prediction and discrimination was developed based on a large multi-center study. The model may be more useful than the FIGO staging system for counseling individual patients regarding prognosis.

  13. Individualized Prediction of Overall Survival After Postoperative Radiation Therapy in Patients With Early-Stage Cervical Cancer: A Korean Radiation Oncology Group Study (KROG 13-03)

    International Nuclear Information System (INIS)

    Lee, Hyun Jin; Han, Seungbong; Kim, Young Seok; Nam, Joo-Hyun; Kim, Hak Jae; Kim, Jae Weon; Park, Won; Kim, Byoung-Gie; Kim, Jin Hee; Cha, Soon Do; Kim, Juree; Lee, Ki-Heon; Yoon, Mee Sun

    2013-01-01

    Purpose: A nomogram is a predictive statistical model that generates the continuous probability of a clinical event such as death or recurrence. The aim of the study was to construct a nomogram to predict 5-year overall survival after postoperative radiation therapy for stage IB to IIA cervical cancer. Methods and Materials: The clinical data from 1702 patients with early-stage cervical cancer, treated at 10 participating hospitals from 1990 to 2011, were reviewed to develop a prediction nomogram based on the Cox proportional hazards model. Demographic, clinical, and pathologic variables were included and analyzed to formulate the nomogram. The discrimination and calibration power of the model was measured using a concordance index (c-index) and calibration curve. Results: The median follow-up period for surviving patients was 75.6 months, and the 5-year overall survival probability was 87.1%. The final model was constructed using the following variables: age, number of positive pelvic lymph nodes, parametrial invasion, lymphovascular invasion, and the use of concurrent chemotherapy. The nomogram predicted the 5-year overall survival with a c-index of 0.69, which was superior to the predictive power of the International Federation of Gynecology and Obstetrics (FIGO) staging system (c-index of 0.54). Conclusions: A survival-predicting nomogram that offers an accurate level of prediction and discrimination was developed based on a large multi-center study. The model may be more useful than the FIGO staging system for counseling individual patients regarding prognosis

  14. American Brachytherapy Society Task Group Report: Combination of brachytherapy and external beam radiation for high-risk prostate cancer.

    Science.gov (United States)

    Spratt, Daniel E; Soni, Payal D; McLaughlin, Patrick W; Merrick, Gregory S; Stock, Richard G; Blasko, John C; Zelefsky, Michael J

    To review outcomes for high-risk prostate cancer treated with combined modality radiation therapy (CMRT) utilizing external beam radiation therapy (EBRT) with a brachytherapy boost. The available literature for high-risk prostate cancer treated with combined modality radiation therapy was reviewed and summarized. At this time, the literature suggests that the majority of high-risk cancers are curable with multimodal treatment. Several large retrospective studies and three prospective randomized trials comparing CMRT to dose-escalated EBRT have demonstrated superior biochemical control with CMRT. Longer followup of the randomized trials will be required to determine if this will translate to a benefit in metastasis-free survival, disease-specific survival, and overall survival. Although greater toxicity has been associated with CMRT compared to EBRT, recent studies suggest that technological advances that allow better definition and sparing of critical adjacent structures as well as increasing experience with brachytherapy have improved implant quality and the toxicity profile of brachytherapy. The role of androgen deprivation therapy is well established in the external beam literature for high-risk disease, but there is controversy regarding the applicability of these data in the setting of dose escalation. At this time, there is not sufficient evidence for the omission of androgen deprivation therapy with dose escalation in this population. Comparisons with surgery remain limited by differences in patient selection, but the evidence would suggest better disease control with CMRT compared to surgery alone. Due to a series of technological advances, modern combination series have demonstrated unparalleled rates of disease control in the high-risk population. Given the evidence from recent randomized trials, combination therapy may become the standard of care for high-risk cancers. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All

  15. Epidemiological surveys on the effects of low-level radiation dose: a comparative assessment. Vol. A: pre-conception irradiation effects. Vol. E (DRAFT A): group collation tables

    Energy Technology Data Exchange (ETDEWEB)

    Rose, K.S.B.

    1988-01-01

    In this report, the health effects of low-level doses of radiation are considered by reference to published epidemiological surveys. The work was carried out with three objectives in mind: 1. to provide a comprehensive and critical review of the subject; 2. to seek consistent indications of particular health effects by collating results and comparing with those from surveys at moderate-level doses; 3. to provide an authoritative view on the epidemiology of low-level radiation-induced health effects. Vol E (DRAFT A) is appended and contains group collation tables. Epidemiological surveys can be conveniently divided into four classes (A, B, C, D) according to the phase of life when irradiation occurs or the effect is diagnosed. The first of the classes (A) is addressed here; this class is concerned with possible effects arising from radiation received by a parent before conception. Possible effects of preconception irradiation were identified under four broad groupings. These are Down's syndrome, ''Indicators of Reproductive Damage'' (mainly Primary Sterility, Congenital Abnormalities, Sex Ratio, Fetal Mortality, Infant Mortality), Childhood Malignancies, and Chromosomal Changes in Abortuses. Information about each survey, and comparisons with results from moderate-level dose surveys, are contained in synopses that are set out in the Appendix.

  16. Repair of damage by ultraviolet radiation in xeroderma pigmentosum cell strains of complementation groups E and F

    NARCIS (Netherlands)

    Zelle, B.; Berends, F.; Lohman, P.H.M.

    1980-01-01

    The xeroderma pignemtosum fibroblast strains XP2RO, complementation group E, and XP23OS, group F were compared with normal human primary fibroblasts UV. regard to repair of damage induced by 254-nn UV> In XP2RO cells, repair DNA synthesis, measured by autoradiography (unscheduled DNA synthesis =

  17. Digital photography as source documentation of skin toxicity: an analysis from the Trans Tasman Radiation Oncology Group (TROG) 04.01 post-mastectomy radiation skin care trial.

    Science.gov (United States)

    Graham, Peter H; Plant, Natalie A; Graham, Jennifer Louise; Browne, Lois H; Borg, Martin; Capp, Anne; Delaney, Geoff P; Harvey, Jennifer; Kenny, Lizbeth; Francis, Michael; Zissiadis, Yvonne

    2012-08-01

    This study evaluated digital photographs as a method of providing auditable source documentation for radiotherapy-induced skin toxicity and the possibility therefore of centralised, blinded scoring for a multicentre randomised controlled trial. Digital photograph sets from the first five patients from each of 12 participating centres were audited. Minimum camera specifications and photograph requirements were protocol specified. Three readers rated photographs for four key quality items. They also scored skin reactions according to National Cancer Institute Common Terminology Criteria (CTC) v3.0 acute skin score and also for the presence of any moist desquamation. Five hundred fifty-two images were available. Field of view was scored as inadequate in 1-10%, focus inadequate in 0.4-4%, lighting inadequate in 0.2-3% and dividing line marking inadequate for scoring of skin reactions within sectors in 18-23% of photographs by three readers. Reader pairwise inter-observer agreement was 83-88% for CTC acute skin scores, but the kappa value ranged from 0.58 to 0.73. The percentage of image sectors not scored by readers due to difficulty in assessing was 1-10%. Moist desquamation was scored by clinicians in 8 (medial)-13% (lateral) of patients compared with 3-5% and 5-11% by readers. Photo reader inter-observer agreement is only moderate. Photo readers tended to underscore the frequency of moist desquamation, but the trend by sector parallels the clinical scorers. Photographs are useful source documents for auditing and monitoring, but not a replacement for clinical scoring. © 2012 The Authors. Journal of Medical Imaging and Radiation Oncology © 2012 The Royal Australian and New Zealand College of Radiologists.

  18. Successful implementation of image-guided radiation therapy quality assurance in the Trans Tasman Radiation Oncology Group 08.01 PROFIT Study.

    Science.gov (United States)

    Middleton, Mark; Frantzis, Jim; Healy, Brendan; Jones, Mark; Murry, Rebecca; Kron, Tomas; Plank, Ashley; Catton, Charles; Martin, Jarad

    2011-12-01

    The quality assurance (QA) of image-guided radiation therapy (IGRT) within clinical trials is in its infancy, but its importance will continue to grow as IGRT becomes the standard of care. The purpose of this study was to demonstrate the feasibility of IGRT QA as part of the credentialing process for a clinical trial. As part of the accreditation process for a randomized trial in prostate cancer hypofraction, IGRT benchmarking across multiple sites was incorporated. Each participating site underwent IGRT credentialing via a site visit. In all centers, intraprostatic fiducials were used. A real-time assessment of analysis of IGRT was performed using Varian's Offline Review image analysis package. Two-dimensional (2D) kV and MV electronic portal imaging prostate patient datasets were used, consisting of 39 treatment verification images for 2D/2D comparison with the digitally reconstructed radiograph derived from the planning scan. The influence of differing sites, image modality, and observer experience on IGRT was then assessed. Statistical analysis of the mean mismatch errors showed that IGRT analysis was performed uniformly regardless of institution, therapist seniority, or imaging modality across the three orthogonal planes. The IGRT component of clinical trials that include sophisticated planning and treatment protocols must undergo stringent QA. The IGRT technique of intraprostatic fiducials has been shown in the context of this trial to be undertaken in a uniform manner across Australia. Extending this concept to many sites with different equipment and IGRT experience will require a robust remote credentialing process. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.

  19. Avoiding Severe Toxicity From Combined BRAF Inhibitor and Radiation Treatment: Consensus Guidelines from the Eastern Cooperative Oncology Group (ECOG)

    Energy Technology Data Exchange (ETDEWEB)

    Anker, Christopher J., E-mail: chris.anker@UVMHealth.org [Division of Radiation Oncology, University of Vermont Cancer Center, Burlington, Vermont (United States); Grossmann, Kenneth F. [Division of Medical Oncology, Department of Medicine, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah (United States); Atkins, Michael B. [Department of Oncology, Georgetown-Lombardi Comprehensive Cancer Center, Georgetown University School of Medicine, Washington, District of Columbia (United States); Suneja, Gita [Department of Radiation Oncology, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah (United States); Tarhini, Ahmad A.; Kirkwood, John M. [Division of Hematology-Oncology, Department of Medicine, University of Pittsburgh Cancer Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States)

    2016-06-01

    BRAF kinase gene V600 point mutations drive approximately 40% to 50% of all melanomas, and BRAF inhibitors (BRAFi) have been found to significantly improve survival outcomes. Although radiation therapy (RT) provides effective symptom palliation, there is a lack of toxicity and efficacy data when RT is combined with BRAFi, including vemurafenib and dabrafenib. This literature review provides a detailed analysis of potential increased dermatologic, pulmonary, neurologic, hepatic, esophageal, and bowel toxicity from the combination of BRAFi and RT for melanoma patients described in 27 publications. Despite 7 publications noting potential intracranial neurotoxicity, the rates of radionecrosis and hemorrhage from whole brain RT (WBRT), stereotactic radiosurgery (SRS), or both do not appear increased with concurrent or sequential administration of BRAFis. Almost all grade 3 dermatitis reactions occurred when RT and BRAFi were administered concurrently. Painful, disfiguring nondermatitis cutaneous reactions have been described from concurrent or sequential RT and BRAFi administration, which improved with topical steroids and time. Visceral toxicity has been reported with RT and BRAFi, with deaths possibly related to bowel perforation and liver hemorrhage. Increased severity of radiation pneumonitis with BRAFi is rare, but more concerning was a potentially related fatal pulmonary hemorrhage. Conversely, encouraging reports have described patients with leptomeningeal spread and unresectable lymphadenopathy rendered disease free from combined RT and BRAFi. Based on our review, the authors recommend holding RT ≥3 days before and after fractionated RT and ≥1 day before and after SRS. No fatal reactions have been described with a dose <4 Gy per fraction, and time off systemic treatment should be minimized. Future prospective data will serve to refine these recommendations.

  20. Limited Chemotherapy and Shrinking Field Radiotherapy for Osteolymphoma (Primary Bone Lymphoma): Results From the Trans-Tasman Radiation Oncology Group 99.04 and Australasian Leukaemia and Lymphoma Group LY02 Prospective Trial

    International Nuclear Information System (INIS)

    Christie, David; Dear, Keith; Le, Thai; Barton, Michael; Wirth, Andrew; Porter, David; Roos, Daniel; Pratt, Gary

    2011-01-01

    Purpose: To establish benchmark outcomes for combined modality treatment to be used in future prospective studies of osteolymphoma (primary bone lymphoma). Methods and Materials: In 1999, the Trans-Tasman Radiation Oncology Group (TROG) invited the Australasian Leukemia and Lymphoma Group (ALLG) to collaborate on a prospective study of limited chemotherapy and radiotherapy for osteolymphoma. The treatment was designed to maintain efficacy but limit the risk of subsequent pathological fractures. Patient assessment included both functional imaging and isotope bone scanning. Treatment included three cycles of CHOP chemotherapy and radiation to a dose of 45 Gy in 25 fractions using a shrinking field technique. Results: The trial closed because of slow accrual after 33 patients had been entered. Accrual was noted to slow down after Rituximab became readily available in Australia. After a median follow-up of 4.3 years, the five-year overall survival and local control rates are estimated at 90% and 72% respectively. Three patients had fractures at presentation that persisted after treatment, one with recurrent lymphoma. Conclusions: Relatively high rates of survival were achieved but the number of local failures suggests that the dose of radiotherapy should remain higher than it is for other types of lymphoma. Disability after treatment due to pathological fracture was not seen.

  1. Cherenkov radiation

    International Nuclear Information System (INIS)

    Hubert, P.

    1955-01-01

    When the radioactivity has been discovered, it was observed by researchers that different materials as mineral salts or solutions were emitting a weak light when submitted to radioactivity beams. At the beginning it has been thought that it was fluorescent light. In 1934, Cherenkov, a russian physicist, worked on the luminescence of uranyl salts solutions caused by gamma radiation and observed a very weak light was emitted by pure liquid. After further studies, he concluded that this phenomena was different from fluorescence. Since then, it has been called Cherenkov effect. This blue light emission is produced when charged particles are going through a transparent medium with an upper velocity than light velocity. This can happen only in medium with large refractive index as water or glass. It also presents its different properties discovered afterwards. The different applications of the Cherenkov radiation are discussed as counting techniques for radiation detectors or comic ray detectors. (M.P.)

  2. Reflection groups

    International Nuclear Information System (INIS)

    Eggermont, G.

    2006-01-01

    In 2005, PISA organised proactive meetings of reflection groups on involvement in decision making, expert culture and ethical aspects of radiation protection.All reflection group meetings address particular targeted audiences while the output publication in book form is put forward

  3. Prognostic factors derived from recursive partition analysis (RPA) of radiation therapy oncology group (RTOG) brain metastases trials applied to surgically resected and irradiated brain metastatic cases

    International Nuclear Information System (INIS)

    Agboola, Olusegun; Benoit, Brien; Cross, Peter; Silva, Vasco da; Esche, Bernd; Lesiuk, Howard; Gonsalves, Carol

    1998-01-01

    Purpose: (a) To identify the prognostic factors that determine survival after surgical resection and irradiation of tumors metastatic to brain. (b) To determine if the prognostic factors used in the recursive partition analysis (RPA) of brain metastases cases from Radiation Therapy Oncology Group (RTOG) studies into three distinct survival classes is applicable to surgically resected and irradiated patients. Method: The medical records of 125 patients who had surgical resection and radiotherapy for brain metastases from 1985 to 1997 were reviewed. The patients' disease and treatment related factors were analyzed to identify factors that independently determine survival after diagnosis of brain metastasis. The patients were also grouped into three classes using the RPA-derived prognostic parameters which are: age, performance status, state of the primary disease, and presence or absence of extracranial metastases. Class 1: patients ≤ 65 years of age, Karnofsky performance status (KPS) of ≥70, with controlled primary disease and no extracranial metastases; Class 3: patients with KPS < 70. Patients who do not qualify for Class 1 or 3 are grouped as Class 2. The survival of these patients was determined from the time of diagnosis of brain metastases to the time of death. Results: The median survival of the entire group was 9.5 months. The three classes of patients as grouped had median survivals of 14.8, 9.9, and 6.0 months respectively (p = 0.0002). Age of < 65 years, KPS of ≥ 70, controlled primary disease, absence of extracranial metastases, complete surgical resection of the brain lesion(s) were found to be independent prognostic factors for survival; the total dose of radiation was not. Conclusion: Based on the results of this study, the patients and disease characteristics have significant impact on the survival of patients with brain metastases treated with a combination of surgical resection and radiotherapy. These parameters could be used in selecting

  4. Estimation of individual doses from external exposures and dose-group classification of cohort members in high background radiation area in Yangjiang, China

    International Nuclear Information System (INIS)

    Yuan Yongling; Shen Hong; Sun Quanfu; Wei Luxin

    1999-01-01

    Objective: In order to estimate annual effective doses from external exposures in the high background radiation area (HBRA) and in the control area (CA) , the authors measured absorbed dose rates in air from terrestrial gamma radiation with different dosimeters. A dose group classification was an important step for analyzing the dose effects relationship among the cohort members in the investigated areas. The authors used the hamlet specific average annual effective doses of all the 526 hamlets in the investigated areas. A classification of four dose groups was made for the cohort members (high, moderate, low and control) . Methods: For the purpose of studying the dose effect relationships among the cohort members in HBRA and CA, it would be ideal that each subject has his own record of individual accumulated doses received before the evaluation. However, rt is difficult to realize it in practice (each of 106517 persons should wear TLD for a long time) . Thus the authors planned two sets of measurements. Firstly, to measure the environmental dose rates (outdoor, indoor, over the bed) in every hamlet of the investigated area (526 hamlets) , considering the occupancy factors for males and females of different age groups to convert to the annual effective dose from the data of dose rates. Secondly, to measure the individual cumulative dose with TLD for part of the subjects in the investigated areas. Results: Based on the two sets of measurements, the estimates of average annual effective doses in HBRA were 211.86 and 206.75 x 10 -5 Sv/a, respectively, 68.60 and 67.11 x 10 -5 Sv/a, respectively(gamma radiation only) . The intercomparison between these two sets of measurement showed that they were in good correlation. Thus the authors are able to yield the equations of linear regression: Y = 0.9937 + 6.0444, r = 0.9949. Conclusions: The authors took the value obtained from direct measurement as 'standard' , and 15 % for uncertainty of measurement. Since the estimates of

  5. Proceedings of the 18th technical meeting on nuclear reactor and radiation for KURRI engineers and the 9th technical official group section 5 meeting in Kyoto University

    International Nuclear Information System (INIS)

    2010-03-01

    This report is a summary of 18th Technical Meeting on Nuclear Reactor and Radiation for KURRI Engineers in Kyoto University. This was also the 9th meeting for technical official group section 5 (nuclear and radiation) in Kyoto University. In the workshop, three special lectures held were: (1) 'On Border Between Subcritical and Supercritical', (2) 'Memories of Nuclear Power Plant Management for 40 Years', and (3) 'Introduction of Technical Office in Faculty of Engineering, Kyoto University'. The technical presentations held were: (1) 'Radiation Background Study of Specialty Products in Senshu Region', (2) 'Introduction of Radioactivation Analysis at KUR', (3) 'Consideration of Critical Approach Method for KUR Low-Enrichment Fuel Reactor Core Using SRAC', (4) 'Evaluation of Temperature Coefficient of KUR Low-Enrichment Fuel Reactor Core Using SRAC'. As training for technical staffs in Technical Office, we visited the facility in Ashiu Research Forest. An introduction of this facility and the comments from the participants were included in this report. (S.K.)

  6. The safe management of sources of radiation: Principles and strategies. INSAG-11. A report by the International Nuclear Safety Advisory Group (Russian Edition)

    International Nuclear Information System (INIS)

    2015-01-01

    The IAEA activities relating to nuclear safety are based upon a number of premises. First and foremost, each Member State bears full responsibility for the safety of its nuclear facilities. States can be advised, but cannot be relieved of this responsibility. Secondly, much can be gained by exchanging experience; lessons learned can prevent accidents. Finally, the image of nuclear safety is international; a serious accident anywhere affects the public view of nuclear power everywhere. With the intention of strengthening its contribution to ensuring safety of nuclear power plants, the IAEA established the International Safety Advisory Group (INSAG), whose duties include serving as a forum for the exchange of information on nuclear safety issues of international significance and formulating commonly shared safety principles. The present report deals with the general principles governing the safety of all sources of radiation and with application of these principles. It intends to show that, at the conceptual level, the distinction traditionally made between nuclear safety and radiation protection is hardly justifiable. It is intended primarily for those non-specialists who need to take decisions about safe management of sources of radiation and who wish to gain a better understanding of the approach followed in managing the safety of these sources

  7. Introduction of online adaptive radiotherapy for bladder cancer through a multicentre clinical trial (Trans-Tasman Radiation Oncology Group 10.01): lessons learned

    International Nuclear Information System (INIS)

    Pham, Daniel; Roxby, Paul; Kron, Tomas; Rolfo, Aldo; Foroudi, Farshad

    2013-01-01

    Online adaptive radiotherapy for bladder cancer is a novel radiotherapy technique that was found feasible in a pilot study at a single academic institution. In September 2010 this technique was opened as a multicenter study through the Trans-Tasman Radiation Oncology Group (TROG 10.01 bladder online adaptive radiotherapy treatment). Twelve centers across Australia and New-Zealand registered interest into the trial. A multidisciplinary team of radiation oncologists, radiation therapists and medical physicists represented the trial credentialing and technical support team. To provide timely activation and proper implementation of the adaptive technique the following key areas were addressed at each site: Staff education/training; Practical image guided radiotherapy assessment; provision of help desk and feedback. The trial credentialing process involved face-to-face training and technical problem solving via full day site visits. A dedicated 'help-desk' team was developed to provide support for the clinical trial. 26% of the workload occurred at the credentialing period while the remaining 74% came post-center activation. The workload was made up of the following key areas; protocol clarification (36%), technical problems (46%) while staff training was less than 10%. Clinical trial credentialing is important to minimizing trial deviations. It should not only focus on site activation quality assurance but also provide ongoing education and technical support. (author)

  8. Introduction of online adaptive radiotherapy for bladder cancer through a multicentre clinical trial (Trans-Tasman Radiation Oncology Group 10.01: Lessons learned

    Directory of Open Access Journals (Sweden)

    Daniel Pham

    2013-01-01

    Full Text Available Online adaptive radiotherapy for bladder cancer is a novel radiotherapy technique that was found feasible in a pilot study at a single academic institution. In September 2010 this technique was opened as a multicenter study through the Trans-Tasman Radiation Oncology Group (TROG 10.01 bladder online adaptive radiotherapy treatment. Twelve centers across Australia and New-Zealand registered interest into the trial. A multidisciplinary team of radiation oncologists, radiation therapists and medical physicists represented the trial credentialing and technical support team. To provide timely activation and proper implementation of the adaptive technique the following key areas were addressed at each site: Staff education/training; Practical image guided radiotherapy assessment; provision of help desk and feedback. The trial credentialing process involved face-to-face training and technical problem solving via full day site visits. A dedicated "help-desk" team was developed to provide support for the clinical trial. 26% of the workload occurred at the credentialing period while the remaining 74% came post-center activation. The workload was made up of the following key areas; protocol clarification (36%, technical problems (46% while staff training was less than 10%. Clinical trial credentialing is important to minimizing trial deviations. It should not only focus on site activation quality assurance but also provide ongoing education and technical support.

  9. Radiotherapeutic management of non-small cell lung cancer (NSCLC). An overview based on the clinical trials of the radiation therapy oncology group (RTOG)

    International Nuclear Information System (INIS)

    Wilson, J.F.; Byhardt, R.W.

    1995-01-01

    Recent clinical trials clarified the role of radiation therapy (RT) in the treatment of non-small cell lung cancer (NSCLC). The evolution of this research is illustrated by a systemic succession of studies conducted during the last twenty years by the Radiation Therapy Oncology Group (RTOG). This article reviews past and present RTOG research efforts in NSCLC. For unresectable NSCLS, major research themes have included radiation dose intensification using both standard and altered fractionation (hyperfractionation or accelerated fraction RT), treatment intensification using combined modality RT and chemotherapy (CT), as well as noncytotoxic adjuvants to RT. These trials have shown that treatment intensification can yield improved survival with acceptable toxicity. Local control and survival was improved with induction CT followed by standard RT to 60 Gy. Current studies will evaluate the timing and sequencing of CT and RT and the combination of CT with altered fractionation RT. Hypoxic cell sensitizers and nonspecific immune stimulants, two noncytotoxic adjuvants to RT, have shown no survival benefit. Biologic response modifiers, including recombinant interferon-beta, will also be evaluated as adjuvants to standard RT, based on interferon-beta radiosensitization observed in the laboratory and clinical investigations suggesting improved survival. Overall, RTOG studies have demonstrated small, but definite, incremental improvements in treatment outcome in NSCLS and provide a solid foundation on which to develop future investigations. (N.K.) 51 refs

  10. The safe management of sources of radiation: Principles and strategies. INSAG-11. A report by the International Nuclear Safety Advisory Group

    International Nuclear Information System (INIS)

    1999-01-01

    The IAEA activities relating to nuclear safety are based upon a number of premises. First and foremost, each Member State bears full responsibility for the safety of its nuclear facilities. States can be advised, but cannot be relieved of this responsibility. Secondly, much can be gained by exchanging experience; lessons learned can prevent accidents. Finally, the image of nuclear safety is international; a serious accident anywhere affects the public view of nuclear power everywhere. With the intention of strengthening its contribution to ensuring safety of nuclear power plants, the IAEA established the International Safety Advisory Group (INSAG), whose duties include serving as a forum for the exchange of information on nuclear safety issues of international significance and formulating commonly shared safety principles. The present report deals with the general principles governing the safety of all sources of radiation and with application of these principles. It intends to show that, at the conceptual level, the distinction traditionally made between nuclear safety and radiation protection is hardly justifiable. It is intended primarily for those non-specialists who need to take decisions about safe management of sources of radiation and who wish to gain a better understanding of the approach followed in managing the safety of these sources

  11. PROSPECTIVE EVALUATION OF AN IN VITRO RADIATION RESISTANCE ASSAY IN LOCALLY ADVANCED CANCER OF THE UTERINE CERVIX: A SOUTHWEST ONCOLOGY GROUP STUDY

    Science.gov (United States)

    Randall, Leslie M; Monk, Bradley J; Moon, James; Parker, Ricardo; Al-Ghazi, Muthana; Wilczynski, Sharon; Fruehauf, John P; Markman, Maurie; Burger, Robert A

    2010-01-01

    Objectives To investigate the feasibility of performing a fresh-tissue, in vitro radiation resistance assay (IVRRA) in a cooperative group setting and to assess the association of IVRRA results with clinical outcomes. Methods Women with Stages IIB-IVA carcinoma of the uterine cervix without obvious para-aortic lymphadenopathy on imaging were eligible. Primary tumor biopsies were shipped to a central testing facility where agar-based cell suspensions were exposed to 300 cGy of RT ± cisplatin and cultured for 5 days. 3H-thymidine incorporation was used to determine percent cell inhibition (PCI) of test specimen compared to that of the untreated control. Tumors were considered to exhibit extreme radiation resistance (ERR), intermediate radiation resistance (IRR) or low radiation resistance (LRR) based on a standard data set from 39 previously studied specimens. Standardized doses of external beam radiation and intracavitary brachytherapy, when feasible, in addition to platinum-based chemotherapy were mandated. Progression-free survival (PFS) was the primary endpoint. Clinical response and overall survival (OS) were secondary endpoints. Clinical investigators were blinded to assay data and vice versa. Results Thirty-six patients were enrolled, but analysis was limited to 17 patients whose specimens were adequate for IVRRA. The median follow-up time was 40 months. There was no association between IVRRA and response. In the Cox model, IRR/ERR tumors showed worse PFS [HR=11.2 (95% CI 1.3–96, p=0.03)] and worse OS [HR=11.7 (95% CI 1.4–99.6, p=0.03)] compared to LRR tumors when IVRRA was performed with RT alone, but there were no associations between IVRRA and PFS or OS when cisplatin was added to the IVRRA. Conclusions IVRRA (RT alone) results correlated with PFS and OS in this prospective trial, but follow-up trials are indicated to address feasibility and to confirm results in an expanded cohort. If confirmed, IVRRA could potentially direct molecular identification

  12. Cherenkov radiation; La radiation Cerenkov

    Energy Technology Data Exchange (ETDEWEB)

    Hubert, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1955-07-01

    When the radioactivity has been discovered, it was observed by researchers that different materials as mineral salts or solutions were emitting a weak light when submitted to radioactivity beams. At the beginning it has been thought that it was fluorescent light. In 1934, Cherenkov, a russian physicist, worked on the luminescence of uranyl salts solutions caused by gamma radiation and observed a very weak light was emitted by pure liquid. After further studies, he concluded that this phenomena was different from fluorescence. Since then, it has been called Cherenkov effect. This blue light emission is produced when charged particles are going through a transparent medium with an upper velocity than light velocity. This can happen only in medium with large refractive index as water or glass. It also presents its different properties discovered afterwards. The different applications of the Cherenkov radiation are discussed as counting techniques for radiation detectors or comic ray detectors. (M.P.)

  13. Low Interrater Reliability in Grading of Rectal Bleeding Using National Cancer Institute Common Toxicity Criteria and Radiation Therapy Oncology Group Toxicity Scales: A Survey of Radiation Oncologists

    International Nuclear Information System (INIS)

    Huynh-Le, Minh-Phuong; Zhang, Zhe; Tran, Phuoc T.; DeWeese, Theodore L.; Song, Daniel Y.

    2014-01-01

    Purpose: To measure concordance among genitourinary radiation oncologists in using the National Cancer Institute Common Toxicity Criteria (NCI CTC) and Radiation Therapy Oncology Group (RTOG) grading scales to grade rectal bleeding. Methods and Materials: From June 2013 to January 2014, a Web-based survey was sent to 250 American and Canadian academic radiation oncologists who treat prostate cancer. Participants were provided 4 case vignettes in which patients received radiation therapy and developed rectal bleeding and were asked for management plans and to rate the bleeding according to NCI CTC v.4 and RTOG late toxicity grading (scales provided). In 2 cases, participants were also asked whether they would send the patient for colonoscopy. A multilevel, random intercept modeling approach was used to assess sources of variation (case, respondent) in toxicity grading to calculate the intraclass correlation coefficient (ICC). Agreement on a dichotomous grading scale (low grades 1-2 vs high grades 3-4) was also assessed, using the κ statistic for multiple respondents. Results: Seventy-two radiation oncologists (28%) completed the survey. Forty-seven (65%) reported having either written or been principal investigator on a study using these scales. Agreement between respondents was moderate (ICC 0.52, 95% confidence interval [CI] 0.47-0.58) when using NCI CTC and fair using the RTOG scale (ICC 0.28, 95% CI 0.20-0.40). Respondents who chose an invasive management were more likely to select a higher toxicity grade (P<.0001). Using the dichotomous scale, we observed moderate agreement (κ = 0.42, 95% CI 0.40-0.44) with the NCI CTC scale, but only slight agreement with the RTOG scale (κ = 0.19, 95% CI 0.17-0.21). Conclusion: Low interrater reliability was observed among radiation oncologists grading rectal bleeding using 2 common scales. Clearer definitions of late rectal bleeding toxicity should be constructed to reduce this variability and avoid ambiguity in both

  14. Dose conversion factors of radiation doses at normal operation discharges. E. Description of geographical surroundings and critical group; Dosomraekningsfaktorer foer normaldriftutslaepp. E. Omraadesbeskrivningar och kritisk grupp

    Energy Technology Data Exchange (ETDEWEB)

    Hallberg, Bengt

    2001-10-01

    A study was performed in order to develop and supplement existing models for calculating radiation doses from discharges of radionuclides under normal operating conditions at the Swedish NPPs at Barsebaeck, Forsmark, Oskarshamn and Ringhals, and at the nuclear plants at Studsvik and the Westinghouse Atom fuel plant. A general description of the surroundings of each plant is given in this report, together with an inventory of agricultural activities, forestry, areas for leisure activities etc. The conditions of the critical group has been selected based on the description of the surroundings and the modeling of dispersion in the atmosphere and fallout on the ground. In contrast to earlier models where fictive critical groups were used, the present model is based on factual circumstances.

  15. Interobserver variability in gross tumor volume delineation for hepatocellular carcinoma. Results of Korean Radiation Oncology Group 1207 study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Suk [Jeju National University School of Medicine, Department of Radiation Oncology, Jeju National University Hospital, Jeju (Korea, Republic of); Kim, Jun Won; Lee, Ik Jae [Yonsei University College of Medicine, Department of Radiation Oncology, Gangnam Severance Hospital, Seoul (Korea, Republic of); Yoon, Won Sup [Korea University Medical Center, Department of Radiation Oncology, Ansan Hospital, Ansan (Korea, Republic of); Kang, Min Kyu [Kyungpook National University School of Medicine, Department of Radiation Oncology, Daegu (Korea, Republic of); Kim, Tae Hyun [National Cancer Center, Center for Liver Cancer, Goyang (Korea, Republic of); Kim, Jin Hee [Keimyung University School of Medicine, Department of Radiation Oncology, Dongsan Medical Center, Daegu (Korea, Republic of); Lee, Hyung-Sik [Dong-A University College of Medicine, Department of Radiation Oncology, Busan (Korea, Republic of); Park, Hee Chul [Sungkyunkwan University School of Medicine, Department of Radiation Oncology, Samsung Medical Center, Seoul (Korea, Republic of); Jang, Hong Seok; Kay, Chul Seung [The Catholic University of Korea College of Medicine, Department of Radiation Oncology, Seoul (Korea, Republic of); Yoon, Sang Min [University of Ulsan College of Medicine, Department of Radiation Oncology, Asan Medical Center, Seoul (Korea, Republic of); Kim, Mi-Sook [Korea Institute of Radiological and Medical Sciences, Department of Radiation Oncology, Seoul (Korea, Republic of); Seong, Jinsil [Yonsei University College of Medicine, Department of Radiation Oncology, Severance Hospital, Seodaemun-gu, Seoul (Korea, Republic of)

    2016-10-15

    There has been increasing use of external beam radiotherapy for localized treatment of hepatocellular carcinoma (HCC) with both palliative and curative intent. Quality control of target delineation in primary HCC is essential to deliver adequate doses of radiation to the primary tumor while preserving adjacent healthy organs. We analyzed interobserver variability in gross tumor volume (GTV) delineation for HCC. Twelve radiation oncologists specializing in liver malignancy participated in a multi-institutional contouring dummy-run study of nine HCC cases and independently delineated GTV on the same set of provided computed tomography images. Quantitative analysis was performed using an expectation maximization algorithm for simultaneous truth and performance level estimation (STAPLE) with kappa statistics calculating agreement between physicians. To quantify the interobserver variability of GTV delineations, the ratio of the actual delineated volume to the estimated consensus volume (STAPLE), the ratio of the common and encompassing volumes, and the coefficient of variation were calculated. The median kappa agreement level was 0.71 (range 0.28-0.86). The ratio of the actual delineated volume to the estimated consensus volume ranged from 0.19 to 1.93 (median 0.94) for all cases. The ratio of the common and encompassing volumes ranged from 0.001 to 0.56 (median 0.25). The coefficient of variation for GTV delineation ranged from 8 to 57 % (median 26 %). The interobserver variability in target delineation of HCC GTV in this study is noteworthy. Multi-institution studies involving radiotherapy for HCC require appropriate quality assurance programs for target delineation. (orig.) [German] Die externe kurative Strahlentherapie ist zunehmend bei der lokalisierten Behandlung hepatozellulaerer Karzinome (HCC) in palliativer und kurativer Absicht in Gebrauch. Eine Qualitaetskontrolle der Zielabgrenzung beim primaeren HCC ist entscheidend, um die passende Dosis fuer die

  16. Efficacy and tolerability of concurrent weekly low dose cisplatin during radiation treatment of localised muscle invasive bladder transitional cell carcinoma: A report of two sequential Phase II studies from the Trans Tasman Radiation Oncology Group

    International Nuclear Information System (INIS)

    Gogna, Nirdosh Kumar; Matthews, John H.L.; Turner, Sandra L.; Mameghan, Heidi; Duchesne, Gillian M.; Spry, Nigel; Berry, Martin P.; Keller, Jacqui; Tripcony, Lee

    2006-01-01

    Background and purpose: To determine the feasibility, toxicity, and clinical effectiveness of concurrent weekly cisplatin chemotherapy in conjunction with definitive radiation in the treatment of localised muscle invasive bladder cancer. Patients and methods: In January 1997 the Trans Tasman Radiation Oncology Group embarked on a Phase II study (TROG 97.01) of weekly cisplatin (35 mg/m 2 x 7 doses) plus radiation to a dose of 63 Gy over 7 weeks. Following an interim toxicity analysis, the dose intensity of cisplatin was reduced to 6 cycles and the radiation schedule changed to 64 Gy over 6.5 weeks leading to the second study (TROG 99.06). A total of 113 patients were enrolled. Results: Acute grade 3 urinary toxicity occurred in 23% of the patients. Acute grade 4 pelvic toxicity was not seen. Thirty-eight patients (33%) experienced grade 3 or 4 cisplatin related toxicities with 15 patients (12%) requiring significant dose modification. The reduced dose intensity in Study 99.06 improved tolerability. Incidence of significant late morbidity was low (6%). Seventy-nine patients (70%) achieved complete remission at the 6 month cystoscopic assessment. Local invasive recurrence was seen in 11 of the 79 patients (14%). In 18 patients (16%) isolated superficial TCC/CIS were detected (6 months and beyond).The local control rate was 45% with a functional bladder being retained in 69 of the 113 patients (61%). RFS and DSS at 5 years were 33% and 50%, respectively. Conclusion: Our two sequential Phase II studies have shown that concurrent chemoradiation using weekly cisplatin in the management of localised invasive bladder TCC is feasible and reasonably well tolerated. This approach is currently being investigated further in a randomised study

  17. Different velocities in wave trains: early definitions and interpretations

    International Nuclear Information System (INIS)

    Lombardi, Anna M

    2002-01-01

    Recent experiments force us to re-examine the physical significance of the different velocities which one can introduce to describe the propagation of a wave train. In this paper we collect together the early definitions of these velocities, and their physical interpretations, dating back to the end of the 19th and to the first decades of the 20th century. Our purpose is to examine the scientific contexts in which some relevant definitions of velocities emerged, with particular attention paid to the early definitions of the group velocity. We recall some debates in which the group velocity had a dominant role, in order to follow the evolution of the physical meanings that have been ascribed to it. Finally, we focus our attention on the connection between the introduction of the group velocity and the problem of white light

  18. The need for central pathology tumor grading in prostate cancer using radiation therapy oncology group(RTOG)8531

    International Nuclear Information System (INIS)

    Winter, K.; Grignon, D.; Pajak, T.F.; Pilepich, M.; Byhardt, R.; Lawton, C.; Gallagher, M.; Mesic, J.; Roach, M.; Hanks, G.; Coughlin, C.; Porter, A.

    1997-01-01

    Purpose/Objective: Inconsistent reproducibility among pathologists when grading the tumor with the Gleason system is well known. Its impact on results and conclusions of clinical trials will be investigated. Materials and Methods: RTOG 8531 was a Phase III trial that tested the timing of hormones with radiotherapy in patients with prostate cancer. There were 977 patients were entered into RTOG 8531, of which 760 had both an institutional and a centrally reviewed Gleason Score(GS). The centrally reviewed GS were performed by a single pathologist and institutional GS came from over 70 different participating institutions. Results: The concordance rate between the grouping of the two scores was 36% (GS 2-5), 70% (GS 6-7) and 73% (GS 8-10) with the discrepancies occurring in both directions. Using patients from the delayed hormone arm, there was a highly significant survival difference between the centrally reviewed GS groups (p = .0001). When the institutional GS groups were used, there was no significant survival difference (p=.19). Another survival analysis compared the treatment arms for GS 8-10 patients. When the centrally reviewed GS were used, there was a significant difference(p = .02), but when the institutional GS were used there was no significant difference in survival between the treatments (p=.48). Conclusions: The lack of reproducibility of Gleason scores among pathologists can lead to very different results and conclusions from clinical trials depending on whether the centrally reviewed or institutional Gleason scores are used. Whenever results are being reported by Gleason score, it is necessary to also report how many pathologists were involved in the grading. If Gleason scores are going to be used in the analysis of treatment, a central review of the Gleason scores is crucial

  19. Examples of Vector Velocity Imaging

    DEFF Research Database (Denmark)

    Hansen, Peter M.; Pedersen, Mads M.; Hansen, Kristoffer L.

    2011-01-01

    To measure blood flow velocity in vessels with conventional ultrasound, the velocity is estimated along the direction of the emitted ultrasound wave. It is therefore impossible to obtain accurate information on blood flow velocity and direction, when the angle between blood flow and ultrasound wa...

  20. Off-label use of medical products in radiation therapy: Summary of the Report of AAPM Task Group No. 121

    International Nuclear Information System (INIS)

    Thomadsen, Bruce R.; Thompson, Heaton H. II; Jani, Shirish K.

    2010-01-01

    approval process, along with manufacturers' responsibilities, labeling, marketing and promotion, and off-label use. This is an educational and descriptive report and does not contain prescriptive recommendations. This report addresses the role of the medical physicist in clinical situations involving off-label use. Case studies in radiation therapy are presented. Any mention of commercial products is for identification only; it does not imply recommendations or endorsements of any of the authors or the AAPM. The full report, containing extensive background on off-label use with several appendices, is available on the AAPM website (http://www.aapm.org/pubs/reports/).

  1. Off-label use of medical products in radiation therapy: Summary of the Report of AAPM Task Group No. 121

    Energy Technology Data Exchange (ETDEWEB)

    Thomadsen, Bruce R.; Thompson, Heaton H. II; Jani, Shirish K. [Department of Medical Physics, University of Wisconsin, Madison, Wisconsin 53705 (United States); Hagerstown, Maryland 21740 (United States); and others

    2010-05-15

    discussion of the approval process, along with manufacturers' responsibilities, labeling, marketing and promotion, and off-label use. This is an educational and descriptive report and does not contain prescriptive recommendations. This report addresses the role of the medical physicist in clinical situations involving off-label use. Case studies in radiation therapy are presented. Any mention of commercial products is for identification only; it does not imply recommendations or endorsements of any of the authors or the AAPM. The full report, containing extensive background on off-label use with several appendices, is available on the AAPM website (http://www.aapm.org/pubs/reports/).

  2. Cerenkov detector for heavy-ion velocity measurements

    International Nuclear Information System (INIS)

    Olson, D.L.; Baumgartner, M.; Dufour, J.P.; Girard, J.G.; Greiner, D.E.; Lindstrom, P.J.; Symons, T.J.M.; Crawford, H.J.

    1984-08-01

    We have developed a highly sensitive velocity measuring detector using total-internal-reflection Cerenkov counters of a type mentioned by Jelly in 1958. If the velocity of the particle is above the threshold for total-internal-reflection these counters have a charge resolution of sigma = 0.18e for a 3mm thick glass radiator. For the velocity measurement we use a fused silica radiator so that the velocity of the particles are near the threshold for total-internal reflection. For momentum-analyzed projectile fragments of 1.6 GeV/nucleon 40 Ar, we have measured a mass resolution of sigma = 0.1u for isotope identification

  3. After Chernobyl - Consequences for energy policy, nuclear safety, radiation and environmental protection. Report of the Expert Group for Nuclear Safety and the environment

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    Chapter B contains a report on the current situation with regard to international nuclear power development, nuclear safety programmes. Swedish emergency preparedness planning, and the phasing out of nuclear power. Chapter C explains the causes of the Chernobyl accident and its course and effects in the Soviet Union. The chapter also contains a summary of earlier reactor accidents, a comparison between the Chernobyl reactor and Swedish reactors, and a discussion of the conclustions that can be drawn with respect to the Swedish reactor safety programme. Chapter D begins with an account of certain basic concepts related to radioactive substances and radiation, our radiological environment, and the effects of radiation. Then follows an account of the risks of nuclear power, and in particular the effects of the Chernobyl accident in Sweden. The Expert Group urges that careful consideration be given to the question of further reinforcement of and other measures concerning preparedness for nuclear power accidents on the basis of the material now available, including the evaluation of emergency operations after the Chernobyl accident. Twelve nuclear power blocks now in operation may be used insofar as safety criteria permit. The Expert Group presents the conditions for and consequences of some alternative, faster phase-out schedules. Chapter E begins with an account of the available substitutes for nuclear power. Different phase-out schedules are then presented. The chapter closes with an estimate of the consequences for the national economy. In Chapter F the Expert Group present a description of risks and environmental problems in relation to the alternative phase-out schedules. (authors).

  4. The role of the article 31 experts group in harmonising the standards for radiation protection in the European Union

    International Nuclear Information System (INIS)

    Govaerts, P.

    2002-01-01

    Article 2 of the Euratom (European Atomic Energy Community) treaty requires the establishment of uniform safety standards to be implemented by each member state: Article 2, b: In order to perform its task the community shall establish uniform safety standards to protect the health of workers and of the general public and ensure that they are applied. The scope of those standards is defined by Article 30 and relates to doses compatible with adequate safety; levels of exposure and contamination; the fundamental principles governing the health surveillance of workers. Article 31 stipulates the decision making process with respect to those standards. Article 31: The basic standards shall be worked out by the Commission after it has obtained the opinion of a group of persons appointed by the Scientific and Technical Committee from among scientific experts, and in particular public health experts, in the Member States. The Commission shall obtain the opinion of the Economic and Social Committee on these basic standards. After consulting the Assembly the Council shall, on a proposal from the Commission, which shall forward to it the opinions from these Committees, establish the basic safety standards; the Council shall act by a qualified majority

  5. Thought experiments at superluminal relative velocities

    International Nuclear Information System (INIS)

    Corben, H.C.

    1976-01-01

    It is imagined that our World is being examined from a similar world which is moving relative to us with a velocity greater than that of light. The two worlds are supposed to be similar in that the particles in each appear to any observer in that world to have real measurable properties. However, the enormous relative velocity so distorts the observations that each world makes on the other that the squares of certain real quantities appear to the other observer to be negative. Neglect of this fact has led to the erroneous belief that a free charged tachyon would emit Cherenkov radiation and that the existence of tachyons would lead to logical paradoxes. (author)

  6. Racial Differences in CYP3A4 Genotype and Survival Among Men Treated on Radiation Therapy Oncology Group (RTOG) 9202: A Phase III Randomized Trial

    International Nuclear Information System (INIS)

    Roach, Mack; Silvio, Michelle de; Rebbick, Timothy; Grignon, David; Rotman, Marvin; Wolkov, Harvey; Fisher, Barbara; Hanks, Gerald; Shipley, William U.; Pollack, Alan; Sandler, Howard; Watkins-Bruner, Deborah Ph.D.

    2007-01-01

    Purpose: Inherited genotypes may explain the inferior outcomes of African American (AA) men with prostate cancer. To understand how variation in CYP3A4 correlated with outcomes, a retrospective examination of the CYP3A4*1B genotype was performed on men treated with Radiation Therapy Oncology Group (RTOG) 92-02. Methods and Materials: From 1,514 cases, we evaluated 56 (28.4%) of 197 AA and 54 (4.3%) of 1,274 European American (EA) patients. All patients received goserelin and flutamide for 2 months before and during RT (STAD-RT) ± 24 months of goserelin (long-term androgen deprivation plus radiation [LTAD-RT]). Events studied included overall survival and biochemical progression using American Society for Therapeutic Radiology and Oncology consensus guidelines. Results: There were no differences in outcome in patients in with or without CYP3A4 data. There was an association between race and CYP3A4 polymorphisms with 75% of EAs having the Wild Type compared to only 25% of AA men (p <0.0001). There was no association between CYP3A4 classification or race and survival or progression. Conclusions: The samples analyzed support previously reported observations about the distribution of CYP3A4*1B genotype by race, but race was not associated with poorer outcome. However, patient numbers were limited, and selection bias cannot be completely ruled out

  7. Testing mitochondrial sequences and anonymous nuclear markers for phylogeny reconstruction in a rapidly radiating group: molecular systematics of the Delphininae (Cetacea: Odontoceti: Delphinidae

    Directory of Open Access Journals (Sweden)

    Kingston Sarah E

    2009-10-01

    Full Text Available Abstract Background Many molecular phylogenetic analyses rely on DNA sequence data obtained from single or multiple loci, particularly mitochondrial DNA loci. However, phylogenies for taxa that have undergone recent, rapid radiation events often remain unresolved. Alternative methodologies for discerning evolutionary relationships under these conditions are desirable. The dolphin subfamily Delphininae is a group that has likely resulted from a recent and rapid radiation. Despite several efforts, the evolutionary relationships among the species in the subfamily remain unclear. Results Here, we compare a phylogeny estimated using mitochondrial DNA (mtDNA control region sequences to a multi-locus phylogeny inferred from 418 polymorphic genomic markers obtained from amplified fragment length polymorphism (AFLP analysis. The two sets of phylogenies are largely incongruent, primarily because the mtDNA tree provides very poor resolving power; very few species' nodes in the tree are supported by bootstrap resampling. The AFLP phylogeny is considerably better resolved and more congruent with relationships inferred from morphological data. Both phylogenies support paraphyly for the genera Stenella and Tursiops. The AFLP data indicate a close relationship between the two spotted dolphin species and recent ancestry between Stenella clymene and S. longirostris. The placement of the Lagenodelphis hosei lineage is ambiguous: phenetic analysis of the AFLP data is consistent with morphological expectations but the phylogenetic analysis is not. Conclusion For closely related, recently diverged taxa, a multi-locus genome-wide survey is likely the most comprehensive approach currently available for phylogenetic inference.

  8. Checkpoint inhibitors and radiation treatment in Hodgkin's lymphoma. New study concepts of the German Hodgkin Study Group

    Energy Technology Data Exchange (ETDEWEB)

    Baues, C.; Semrau, R.; Marnitz, S. [University of Cologne, Medical Faculty, Department of Radiooncology, Cologne (Germany); University of Cologne, German Hodgkin Study Group (GHSG), Cologne (Germany); Gaipl, U.S. [University Hospital Erlangen, Department of Radiooncology, Erlangen (Germany); Broeckelmann, P.J.; Engert, A. [University of Cologne, German Hodgkin Study Group (GHSG), Cologne (Germany); University of Cologne, Medical Faculty, Department of Internal Medicine I, Cologne (Germany); Rosenbrock, J. [University of Cologne, Medical Faculty, Department of Radiooncology, Cologne (Germany)

    2017-02-15

    Patients with classical Hodgkin's lymphoma (cHL) have a good prognosis even in advanced stages. However, combined chemo- and radiotherapy, as the standard of care, is also associated with treatment-related toxicities such as organ damage, secondary neoplasias, infertility, or fatigue and long-term fatigue. Many patients suffer from this burden although their cHL was cured. Therefore, the efficacy of immune checkpoint inhibitors like anti-PD1/PD-L1 antibodies in the treatment of solid cancers and also in HL offers new options. A remarkable and durable response rate with a favorable toxicity profile was observed in heavily pretreated cHL patients. Planning to perform prospective randomized clinical trials in the content of radio-immune treatment in patients with Hodgkin's lymphoma (HL), we transferred the results of preliminary clinical studies and basic research in clinical relevant study concepts. Based on these promising early phase trial data, the German Hodgkin Study Group (GHSG) will investigate innovative treatment regimens in upcoming phase II trials. The therapeutic efficacy and potential synergies of anti-PD1 antibodies in combination with chemo- or radiotherapy will be investigated in various settings of HL. (orig.) [German] Patienten mit einem klassischen Hodgkin-Lymphom (cHL) haben ueber alle Stadien hinweg eine gute Prognose. Allerdings treten unter der kombinierten Therapie mit Chemotherapie und Bestrahlung therapieabhaengige Toxizitaeten wie z. B. Organschaeden, Sekundaertumoren, Fatigue oder Langzeit-Fatigue auf. Viele Patienten leiden trotz einer Heilung an diesen Symptomen. Daher bietet die nachgewiesene Wirksamkeit der Anti-PD1/PD-L1-Antikoerper bei soliden Tumoren, aber auch beim HL neue Behandlungsoptionen. Bei intensiv vorbehandelten Patienten mit rezidiviertem cHL wurde bei guter Vertraeglichkeit eine hohe Ansprechrate mit z. T. langanhaltenden Remissionen beobachtet. Im Rahmen der Planung prospektiver randomisierter Studien im

  9. Doppler Lidar Vertical Velocity Statistics Value-Added Product

    Energy Technology Data Exchange (ETDEWEB)

    Newsom, R. K. [DOE ARM Climate Research Facility, Washington, DC (United States); Sivaraman, C. [DOE ARM Climate Research Facility, Washington, DC (United States); Shippert, T. R. [DOE ARM Climate Research Facility, Washington, DC (United States); Riihimaki, L. D. [DOE ARM Climate Research Facility, Washington, DC (United States)

    2015-07-01

    Accurate height-resolved measurements of higher-order statistical moments of vertical velocity fluctuations are crucial for improved understanding of turbulent mixing and diffusion, convective initiation, and cloud life cycles. The Atmospheric Radiation Measurement (ARM) Climate Research Facility operates coherent Doppler lidar systems at several sites around the globe. These instruments provide measurements of clear-air vertical velocity profiles in the lower troposphere with a nominal temporal resolution of 1 sec and height resolution of 30 m. The purpose of the Doppler lidar vertical velocity statistics (DLWSTATS) value-added product (VAP) is to produce height- and time-resolved estimates of vertical velocity variance, skewness, and kurtosis from these raw measurements. The VAP also produces estimates of cloud properties, including cloud-base height (CBH), cloud frequency, cloud-base vertical velocity, and cloud-base updraft fraction.

  10. Solar Electromagnetic Radiation Study for Solar Cycle 22: Solar Ultraviolet Irradiance, 120 to 300 NM: Report of Working Groups 2 and 3 of SOLERS 22

    Science.gov (United States)

    Rottman, G. J.; Cebula, R. P.; Gillotay, D.; Simon, P. A.

    1996-01-01

    This report summarizes the activities of Working Group 2 and Working Group 3 of the SOLax Electromagnetic Radiation Study for Solar Cycle 22 (SOLERS22) Program. The international (SOLERS22) is Project 1.2 of the Solar-Terrestrial Energy Program (STEP) sponsored by SCOSTEP, a committee of the International Council of Scientific Unions). SOLERS22 is comprised of five Working Groups, each concentrating on a specific wave-length range: WG-1 - visible and infrared, WG-2 - mid-ultraviolet (200 < A < 300 nm), WG-3 - Far-ultraviolet (lambda greater than 100 and lambda less than 200 nanometers), WG-4 - extreme-ultraviolet (lambda greater than 10 and lambda less than 100 nm), and WG-5 - X-ray (lambda greater than 1 and lambda less than 10 nano meters). The overarching goals of SOLERS22 are to: 1) establish daily solar irradiance values in the specified wavelength ranges, 2) consider the evolving solar structures as the cause of temporal variations, and 3) understand the underlying physical processes driving these changes.

  11. Activities of Project 'Cooperation and development with Latin America and Iberian in Biological Dosimetry of Iberian Group of Radiation Protection Societies

    International Nuclear Information System (INIS)

    Nasazzi, Nora B.; Taja, Maria R.; Giorgio, Marina di; Garcia Lima, Omar; Lamadrid, Ana I.; Olivares, Pilar; Moreno, Mercedes; Prieto, Maria J.; Espinosa, Marco

    2001-01-01

    In 1996 the GRIAPRA Group (Latin American and Iberian Group of Radiation Protection Societies) was established with the participation of Argentina, Brazil, Cuba, Mexico, Peru, Portugal and Spain. In 1998 began the biennial Collaborative Working Project 'Cooperation and Development with Latin America in Biological Dosimetry', partially supported by the Extremadura Government, Spain, initially involving five countries: Argentina, Cuba, Peru, Portugal and Spain. The general aim of the project is to create an Latin American and Iberian Biological Dosimetry Laboratories Coordinated Group in order to: give mutual cooperation and to other countries if required, in the case of radiological accident; contribute to enhance the technical capabilities of the participant laboratories; promote the installment of laboratories on this field in countries that does not have it yet through the training of human resources and providing the necessary equipment and, finally, perform jointly research activities in biological dosimetry. The activities designed in order to accomplish the project specific aims for the 1998-2000 period have been achieved. Description and results are presented. (author)

  12. Radiation-Induced Graft Polymerization of Vinyl Monomers with Anion Groups onto MWNT Supports and Their Application as Electrogenerated Chemiluminescence (ECL Biosensors

    Directory of Open Access Journals (Sweden)

    Ji-Hye Park

    2014-01-01

    Full Text Available Vinyl polymer-grafted multiwalled carbon nanotube (MWNT supports with anion groups were prepared for use as biosensor supports by radiation-induced graft polymerization (RIGP of the vinyl monomers acryloyl diphosphoric acid (ADPA, acrylic acid (AA, sodium styrenesulfonate (NaSS, and methacrylic acid (MA onto the surface of MWNTs. The electrogenerated chemiluminescence sensors based on a glass carbon electrode (ECL-GCE and a screen printed electrode (ECL-SPE were fabricated by immobilization of Ru(bpy3 2+ complex after coating of vinyl polymer-grafted MWNT inks on the surface of the GCE and SPE without any polymer binders in order to obtain high electrogenerated chemiluminescence intensity. For detection of alcohol concentration, alcohol dehydrogenase (ADH was immobilized onto an ECL-GCE sensor prepared by poly(NaSS-g-MWNT supports. The prepared biosensor based on ADH is suitable for the detection of ethanol concentration in commercial drinks.

  13. Phase I trial of erlotinib with radiation therapy in patients with glioblastoma multiforme: Results of North Central Cancer Treatment Group protocol N0177

    International Nuclear Information System (INIS)

    Krishnan, Sunil; Brown, Paul D.; Ballman, Karla V.; Fiveash, John B.; Uhm, Joon H.; Giannini, Caterina; Jaeckle, Kurt A.; Geoffroy, Francois J.; Nabors, L. Burt; Buckner, Jan C.

    2006-01-01

    Purpose: To evaluate the toxicity and maximum tolerated dose (MTD) of erlotinib plus radiation therapy (RT) in patients with glioblastoma multiforme (GBM) in a multicenter phase I trial. Methods and Materials: Patients were stratified on the basis of the use of enzyme-inducing anticonvulsants (EIACs). After resection or biopsy, patients were treated with erlotinib for 1 week before concurrent erlotinib and 6 weeks (60 Gy) of RT and maintained on erlotinib until progression. The erlotinib dose was escalated in cohorts of 3 starting at 100 mg/day. Results: Twenty patients were enrolled and 19 were evaluable for the MTD and efficacy endpoints. Of these patients, 14 were males and 5 were females, with a median age of 54 years. Seven had undergone biopsy only, 5 had subtotal resections, and 7 had gross total resections. The highest dose level was 150 mg/day erlotinib for patients not on EIACs (Group 1) and 200 mg/day for patients on EIACs (Group 2). MTD was not reached in either group. In Group 1 at 100 mg (n = 6) and at 150 mg (n = 4), only 1 dose-limiting toxicity (DLT) occurred (stomatitis at 100 mg). No DLTs have occurred in Group 2 at 100 mg (n = 3), 150 mg (n = 3), and 200 mg (n = 3). With a median follow-up of 52 weeks, progression was documented in 16 patients and 13 deaths occurred. Median time to progression was 26 weeks, and median survival was 55 weeks. Conclusion: Toxicity is acceptable at the current doses of erlotinib plus RT. The study was modified to include concurrent and adjuvant temozolomide, and accrual is in progress

  14. Development of an optimal velocity selection method with velocity obstacle

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Min Geuk; Oh, Jun Ho [KAIST, Daejeon (Korea, Republic of)

    2015-08-15

    The Velocity obstacle (VO) method is one of the most well-known methods for local path planning, allowing consideration of dynamic obstacles and unexpected obstacles. Typical VO methods separate a velocity map into a collision area and a collision-free area. A robot can avoid collisions by selecting its velocity from within the collision-free area. However, if there are numerous obstacles near a robot, the robot will have very few velocity candidates. In this paper, a method for choosing optimal velocity components using the concept of pass-time and vertical clearance is proposed for the efficient movement of a robot. The pass-time is the time required for a robot to pass by an obstacle. By generating a latticized available velocity map for a robot, each velocity component can be evaluated using a cost function that considers the pass-time and other aspects. From the output of the cost function, even a velocity component that will cause a collision in the future can be chosen as a final velocity if the pass-time is sufficiently long enough.

  15. Comparative assessment of radiation versus nutritional and other factors that may influence immune status. Report of a Joint IAEA/WHO advisory group meeting, Vienna, Austria, 3-6 May 1994

    International Nuclear Information System (INIS)

    1994-01-01

    An Advisory Group Meeting was convened jointly by the International Atomic Energy Agency and the World Health Organization in May 1994 to review the role of radiation, nutrition, toxic chemicals and other factors that may influence immune status in human populations. Priorities for future research were proposed, and possibilities for using isotope in such studies were identified. The Group recommended that the IAEA should initiate a broadly based Co-ordinated Research Programme (CRP) focussed mainly on the effects of low-level radiation on immune status in human populations. The main variables of interest are (i) the level of individual radiation exposure, and (ii) the nutritional status. Possible experimental groups include persons living in areas of high radiation background (e.g. in countries where areas of high radiation background are known to occur naturally, or at high altitudes, or in areas affected by Chernobyl accident). Other possible experimental groups comprise radiation workers and uranium miners. It was also recommended that the contribution of toxic chemical exposure to immune dysfunction in these population groups should be assessed. Such research should be complemented by animal studies, and possibly also by in vitro studies with human and animal cells, by some participants in the CRP. This report has been prepared as a source of information for potential participants in the proposed CRP and for other persons associated with related programmes of the IAEA and the WHO. 15 refs, 1 fig., 7 tabs

  16. Tumor bulk as a prognostic factor for the management of localized aggressive non-Hodgkin's lymphoma: a survey of the Japan lymphoma radiation therapy group

    International Nuclear Information System (INIS)

    Oguchi, Masahiko; Ikeda, Hiroshi; Isobe, Kouichi; Hirota, Saeko; Hasegawa, Masatoshi; Nakamura, Katsumasa; Sasai, Keisuke; Hayabuchi, Naofumi

    2000-01-01

    Purpose: To identify the prognostic factors that specifically predict survival rates of patients with localized aggressive non-Hodgkin's lymphoma (NHL). Methods and Materials: The survey was carried out at 25 radiation oncology institutions in Japan in 1998. The 5-year event-free (EFS) and overall survival rates (OAS) were calculated, and univariate and multivariate analyses were done to identify which of the following factors, namely, gender, age, performance status (PS), serum lactate dehydrogenase (LDH) level, Stage (I vs. II), tumor bulk (maximum diameter), and treatment, were significant from the viewpoint of prognosis. Results: A total of 1141 patients with Stage I and II NHL were treated by the Japanese Lymphoma Radiation Therapy Group between 1988 and 1992. Of them, 787 patients, who were treated using definitive radiotherapy with or without chemotherapy for intermediate- and high-grade lymphomas in working formulation, constituted the core of this study. Primary tumors arose mainly from extranodal organs (71%) in the head and neck (Waldeyer's ring: 36% and sinonasal cavities: 9%). The factors associated with poorer prognosis were age over 60 years old (p < 0.0001), radiation therapy alone (p < 0.0001), PS = 2-4 (p = 0.0011), (sex male, p = 0.0078), a bulky tumor more than 6 cm in maximum diameter (p 0.0088), elevated LDH (p = 0.0117), and stage II (p = 0.0642). A median dose of 42 Gy was delivered mainly to the involved fields. Short-course chemotherapy was provided in 549 (70%) patients. The 5-year OAS and EFS rates for all patients were 71% and 67%, respectively. According to the stage-modified International Prognostic Index, the 5-year EFS of the patients with risk factors from 0 to 1 was 76%, 61% for patients with two risk factors, and 26% for patients with three or more risk factors. Conclusion: Extranodal presentation, especially Waldeyer's ring and sinonasal cavities, is encountered more frequently in Japan than in Western countries. Tumor bulk is

  17. Are Radiation Therapy Oncology Group Para-aortic Contouring Guidelines for Pancreatic Neoplasm Applicable to Other Malignancies—Assessment of Nodal Distribution in Gynecological Malignancies

    Energy Technology Data Exchange (ETDEWEB)

    Kabolizadeh, Peyman; Fulay, Suyash; Beriwal, Sushil, E-mail: beriwals@upmc.edu

    2013-09-01

    Purpose: Intensity modulated radiation therapy is used to reduce dose to adjacent critical structures while maintaining adequate target coverage, but it requires precise target localization. We report the 3-dimensional distribution of para-aortic (PA) lymph nodes (LN) in pelvic malignancies. We propose a guideline to accurately define the PA LN by anatomic landmarks and compare our data with published guidelines for pancreatic cancer. Methods and Materials: A retrospective analysis was performed on 46 patients with pelvic malignancies and positive PA LNs. Positive LNs were defined based on size and morphology or fluorodeoxyglucose avidity. All PA LNs were characterized into 3 groups based on location: left PA (between aorta and left psoas muscle), aortocaval (between aorta and inferior vena cava), and right paracaval (between inferior vena cava and right psoas muscle). Patients with retrocrural LNs were also analyzed. Results: One hundred thirty-three positive PA LNs were evaluated. The majority of the PA LNs were in the left PA (59%) and aortocaval (35) regions, and only 8% were in the right paracaval region. All patients with positive right paracaval LNs also had involved left PA LNs, with only 1 exception. The highest PA LN involvement was at the level of the renal vessels and was seen in 28% of patients. Of these patients with disease extending to renal vessels, 38% had retrocrural LN involvement. Conclusions: The nodal contouring for the PA region should not be defined by a fixed circumferential margin around the vessels. The left PA and aortocaval spaces should be covered adequately because these are common locations of PA LNs. For microscopic disease superiorly, contouring should extend up to renal vessels rather than a fixed bony landmark. For patients who have nodal involvement at renal vessels, one can consider including retrocrural LNs. Radiation Therapy Oncology Group Para-aortic Contouring Guidelines for Pancreatic Neoplasm are not applicable to

  18. Are Radiation Therapy Oncology Group Para-aortic Contouring Guidelines for Pancreatic Neoplasm Applicable to Other Malignancies—Assessment of Nodal Distribution in Gynecological Malignancies

    International Nuclear Information System (INIS)

    Kabolizadeh, Peyman; Fulay, Suyash; Beriwal, Sushil

    2013-01-01

    Purpose: Intensity modulated radiation therapy is used to reduce dose to adjacent critical structures while maintaining adequate target coverage, but it requires precise target localization. We report the 3-dimensional distribution of para-aortic (PA) lymph nodes (LN) in pelvic malignancies. We propose a guideline to accurately define the PA LN by anatomic landmarks and compare our data with published guidelines for pancreatic cancer. Methods and Materials: A retrospective analysis was performed on 46 patients with pelvic malignancies and positive PA LNs. Positive LNs were defined based on size and morphology or fluorodeoxyglucose avidity. All PA LNs were characterized into 3 groups based on location: left PA (between aorta and left psoas muscle), aortocaval (between aorta and inferior vena cava), and right paracaval (between inferior vena cava and right psoas muscle). Patients with retrocrural LNs were also analyzed. Results: One hundred thirty-three positive PA LNs were evaluated. The majority of the PA LNs were in the left PA (59%) and aortocaval (35) regions, and only 8% were in the right paracaval region. All patients with positive right paracaval LNs also had involved left PA LNs, with only 1 exception. The highest PA LN involvement was at the level of the renal vessels and was seen in 28% of patients. Of these patients with disease extending to renal vessels, 38% had retrocrural LN involvement. Conclusions: The nodal contouring for the PA region should not be defined by a fixed circumferential margin around the vessels. The left PA and aortocaval spaces should be covered adequately because these are common locations of PA LNs. For microscopic disease superiorly, contouring should extend up to renal vessels rather than a fixed bony landmark. For patients who have nodal involvement at renal vessels, one can consider including retrocrural LNs. Radiation Therapy Oncology Group Para-aortic Contouring Guidelines for Pancreatic Neoplasm are not applicable to

  19. Metabolic Tumor Volume as a Prognostic Imaging-Based Biomarker for Head-and-Neck Cancer: Pilot Results From Radiation Therapy Oncology Group Protocol 0522

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, David L., E-mail: david.schwartz@utsw.edu [Department of Radiation Oncology, University of Texas Southwestern School of Medicine, Dallas, Texas (United States); Harris, Jonathan [Radiation Therapy Oncology Group Statistical Center, Philadelphia, Pennsylvania (United States); Yao, Min [Department of Radiation Oncology, Case Western Reserve University School of Medicine, Cleveland, Ohio (United States); Rosenthal, David I. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Opanowski, Adam; Levering, Anthony [American College of Radiology Imaging Network, Philadelphia, Pennsylvania (United States); Ang, K. Kian [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Trotti, Andy M. [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida (United States); Garden, Adam S. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Jones, Christopher U. [Sutter Medical Group, Sacramento, California (United States); Harari, Paul [Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin (United States); Foote, Robert [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Holland, John [Department of Radiation Medicine, Oregon Health & Science University, Portland, Oregon (United States); Zhang, Qiang [Radiation Therapy Oncology Group Statistical Center, Philadelphia, Pennsylvania (United States); Le, Quynh-Thu [Department of Radiation Oncology, Stanford University School of Medicine, Palo Alto, California (United States)

    2015-03-15

    Purpose: To evaluate candidate fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) imaging biomarkers for head-and-neck chemoradiotherapy outcomes in the cooperative group trial setting. Methods and Materials: Radiation Therapy Oncology Group (RTOG) protocol 0522 patients consenting to a secondary FDG-PET/CT substudy were serially imaged at baseline and 8 weeks after radiation. Maximum standardized uptake value (SUVmax), SUV peak (mean SUV within a 1-cm sphere centered on SUVmax), and metabolic tumor volume (MTV) using 40% of SUVmax as threshold were obtained from primary tumor and involved nodes. Results: Of 940 patients entered onto RTOG 0522, 74 were analyzable for this substudy. Neither high baseline SUVmax nor SUVpeak from primary or nodal disease were associated with poor treatment outcomes. However, primary tumor MTV above the cohort median was associated with worse local-regional control (hazard ratio 4.01, 95% confidence interval 1.28-12.52, P=.02) and progression-free survival (hazard ratio 2.34, 95% confidence interval 1.02-5.37, P=.05). Although MTV and T stage seemed to correlate (mean MTV 6.4, 13.2, and 26.8 for T2, T3, and T4 tumors, respectively), MTV remained a strong independent prognostic factor for progression-free survival in bivariate analysis that included T stage. Primary MTV remained prognostic in p16-associated oropharyngeal cancer cases, although sample size was limited. Conclusion: High baseline primary tumor MTV was associated with worse treatment outcomes in this limited patient subset of RTOG 0522. Additional confirmatory work will be required to validate primary tumor MTV as a prognostic imaging biomarker for patient stratification in future trials.

  20. Surface wave velocity tracking by bisection method

    International Nuclear Information System (INIS)

    Maeda, T.

    2005-01-01

    Calculation of surface wave velocity is a classic problem dating back to the well-known Haskell's transfer matrix method, which contributes to solutions of elastic wave propagation, global subsurface structure evaluation by simulating observed earthquake group velocities, and on-site evaluation of subsurface structure by simulating phase velocity dispersion curves and/or H/V spectra obtained by micro-tremor observation. Recently inversion analysis on micro-tremor observation requires efficient method of generating many model candidates and also stable, accurate, and fast computation of dispersion curves and Raleigh wave trajectory. The original Haskell's transfer matrix method has been improved in terms of its divergence tendency mainly by the generalized transmission and reflection matrix method with formulation available for surface wave velocity; however, root finding algorithm has not been fully discussed except for the one by setting threshold to the absolute value of complex characteristic functions. Since surface wave number (reciprocal to the surface wave velocity multiplied by frequency) is a root of complex valued characteristic function, it is intractable to use general root finding algorithm. We will examine characteristic function in phase plane to construct two dimensional bisection algorithm with consideration on a layer to be evaluated and algorithm for tracking roots down along frequency axis. (author)

  1. Modelling Radiation Exposure and Radionuclide Transfer for Non-human Species. Report of the Biota Working Group of EMRAS Theme 3

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-06-15

    Internationally, the ICRP, IAEA and European Commission (EC) are addressing environmental protection as an element of their revision of Recommendations and Basic Safety Standards. Some countries already have requirements and guidelines for the protection of non-human biota. For instance, in England and Wales, the requirement to assess impacts affecting Natura 2000 sites has been interpreted to include ionising radiation. In the USA, biota protection guidelines and dose rates are contained in USDOE Orders 5400.5 and 450.1. In response to these developments, a number of models and approaches have been developed specifically to estimate the exposure of non-human biota to ionising radiations. Some countries (e.g. Canada, Finland, England and Wales, and the USA) are now using these within their national regulatory frameworks for (existing and proposed) nuclear and other sites that may release radioactivity to the environment. Software and/or documentation for some of these approaches are readily available and hence third parties are able to use them when conducting assessments. The Biota Working Group (BWG) of the IAEA Environmental Modelling for Radiation Safety programme was formed in 2004 to address the relative lack of validation and intercomparison of the different models and approaches. The primary objective of the BWG, was: 'to improve Member State's capabilities for protection of the environment by comparing and validating models being used, or developed, for biota dose assessment (that may be used) as part of regulatory process of licensing and compliance monitoring of authorised releases of radionuclides'. Group members included modellers, regulators, industry and researchers. In total, 15 models and approaches were applied to one or more of the four exercises conducted by the BWG. The models/approaches applied encompass those being developed, and in some instances, used in a regulatory context, in Belgium, Canada, France, Lithuania, Russia, the UK and the USA

  2. Modelling Radiation Exposure and Radionuclide Transfer for Non-human Species. Report of the Biota Working Group of EMRAS Theme 3

    International Nuclear Information System (INIS)

    2012-01-01

    Internationally, the ICRP, IAEA and European Commission (EC) are addressing environmental protection as an element of their revision of Recommendations and Basic Safety Standards. Some countries already have requirements and guidelines for the protection of non-human biota. For instance, in England and Wales, the requirement to assess impacts affecting Natura 2000 sites has been interpreted to include ionising radiation. In the USA, biota protection guidelines and dose rates are contained in USDOE Orders 5400.5 and 450.1. In response to these developments, a number of models and approaches have been developed specifically to estimate the exposure of non-human biota to ionising radiations. Some countries (e.g. Canada, Finland, England and Wales, and the USA) are now using these within their national regulatory frameworks for (existing and proposed) nuclear and other sites that may release radioactivity to the environment. Software and/or documentation for some of these approaches are readily available and hence third parties are able to use them when conducting assessments. The Biota Working Group (BWG) of the IAEA Environmental Modelling for Radiation Safety programme was formed in 2004 to address the relative lack of validation and intercomparison of the different models and approaches. The primary objective of the BWG, was: 'to improve Member State's capabilities for protection of the environment by comparing and validating models being used, or developed, for biota dose assessment (that may be used) as part of regulatory process of licensing and compliance monitoring of authorised releases of radionuclides'. Group members included modellers, regulators, industry and researchers. In total, 15 models and approaches were applied to one or more of the four exercises conducted by the BWG. The models/approaches applied encompass those being developed, and in some instances, used in a regulatory context, in Belgium, Canada, France, Lithuania, Russia, the UK and the USA

  3. Spatially-resolved velocities of thermally-produced spray droplets using a velocity-divided Abel inversion of photographed streaks

    Science.gov (United States)

    Kawaguchi, Y.; Kobayashi, N.; Yamagata, Y.; Miyazaki, F.; Yamasaki, M.; Muraoka, K.

    2017-10-01

    Droplet velocities of thermal spray are known to have profound effects on important coating qualities, such as adhesive strength, porosity, and hardness, for various applications. For obtaining the droplet velocities, therefore, the TOF (time-of-flight) technique has been widely used, which relies on observations of emitted radiation from the droplets, where all droplets along the line-of-sight contribute to signals. Because droplets at and near the flow axis mostly contribute coating layers, it has been hoped to get spatially resolved velocities. For this purpose, a velocity-divided Abel inversion was devised from CMOS photographic data. From this result, it has turned out that the central velocity is about 25% higher than that obtained from the TOF technique for the case studied (at the position 150 mm downstream of the plasma spray gun, where substrates for spray coatings are usually placed). Further implications of the obtained results are discussed.

  4. Clinical value of liver and spleen shear wave velocity in predicting the prognosis of patients with portal hypertension.

    Science.gov (United States)

    Zhang, Yan; Mao, Da-Feng; Zhang, Mei-Wu; Fan, Xiao-Xiang

    2017-12-07

    To explore the relationship of liver and spleen shear wave velocity in patients with liver cirrhosis combined with portal hypertension, and assess the value of liver and spleen shear wave velocity in predicting the prognosis of patients with portal hypertension. All 67 patients with liver cirrhosis diagnosed as portal hypertension by hepatic venous pressure gradient in our hospital from June 2014 to December 2014 were enrolled into this study. The baseline information of these patients was recorded. Furthermore, 67 patients were followed-up at 20 mo after treatment, and liver and spleen shear wave velocity were measured by acoustic radiation force impulse at the 1 st week, 3 rd month and 9 th month after treatment. Patients with favorable prognosis were assigned into the favorable prognosis group, while patients with unfavorable prognosis were assigned into the unfavorable prognosis group. The variation and difference in liver and spleen shear wave velocity in these two groups were analyzed by repeated measurement analysis of variance. Meanwhile, in order to evaluate the effect of liver and spleen shear wave velocity on the prognosis of patients with portal hypertension, Cox's proportional hazard regression model analysis was applied. The ability of those factors in predicting the prognosis of patients with portal hypertension was calculated through receiver operating characteristic (ROC) curves. The liver and spleen shear wave velocity in the favorable prognosis group revealed a clear decline, while those in the unfavorable prognosis group revealed an increasing tendency at different time points. Furthermore, liver and spleen shear wave velocity was higher in the unfavorable prognosis group, compared with the favorable prognosis group; the differences were statistically significant ( P portal hypertension was significantly affected by spleen hardness at the 3 rd month after treatment [relative risk (RR) = 3.481]. At the 9 th month after treatment, the prognosis

  5. Control rod velocity limiter

    International Nuclear Information System (INIS)

    Cearley, J.E.; Carruth, J.C.; Dixon, R.C.; Spencer, S.S.; Zuloaga, J.A. Jr.

    1986-01-01

    This patent describes a velocity control arrangement for a reciprocable, vertically oriented control rod for use in a nuclear reactor in a fluid medium, the control rod including a drive hub secured to and extending from one end therefrom. The control device comprises: a toroidally shaped control member spaced from and coaxially positioned around the hub and secured thereto by a plurality of spaced radial webs thereby providing an annular passage for fluid intermediate the hub and the toroidal member spaced therefrom in coaxial position. The side of the control member toward the control rod has a smooth generally conical surface. The side of the control member away from the control rod is formed with a concave surface constituting a single annular groove. The device also comprises inner and outer annular vanes radially spaced from one another and spaced from the side of the control member away from the control rod and positioned coaxially around and spaced from the hub and secured thereto by spaced radial webs thereby providing an annular passage for fluid intermediate the hub and the vanes. The vanes are angled toward the control member, the outer edge of the inner vane being closer to the control member and the inner edge of the outer vane being closer to the control member. When the control rod moves in the fluid in the direction toward the drive hub the vanes direct a flow of fluid turbulence which provides greater resistance to movement of the control rod in the direction toward the drive hub than in the other direction

  6. Velocity Dispersions Across Bulge Types

    International Nuclear Information System (INIS)

    Fabricius, Maximilian; Bender, Ralf; Hopp, Ulrich; Saglia, Roberto; Drory, Niv; Fisher, David

    2010-01-01

    We present first results from a long-slit spectroscopic survey of bulge kinematics in local spiral galaxies. Our optical spectra were obtained at the Hobby-Eberly Telescope with the LRS spectrograph and have a velocity resolution of 45 km/s (σ*), which allows us to resolve the velocity dispersions in the bulge regions of most objects in our sample. We find that the velocity dispersion profiles in morphological classical bulge galaxies are always centrally peaked while the velocity dispersion of morphologically disk-like bulges stays relatively flat towards the center--once strongly barred galaxies are discarded.

  7. On linear relationship between shock velocity and particle velocity

    International Nuclear Information System (INIS)

    Dandache, H.

    1986-11-01

    We attempt to derive the linear relationship between shock velocity U s and particle velocity U p from thermodynamic considerations, taking into account an ideal gas equation of state and a Mie-Grueneisen equation of state for solids. 23 refs

  8. Genetic analysis of peripheral nerve conduction velocity in twins

    NARCIS (Netherlands)

    Rijsdijk, F.V.; Boomsma, D.I.; Vernon, P.A.

    1995-01-01

    We studied variation in peripheral nerve conduction velocity (PNCV) and intelligence in a group of 16-year-old Dutch twins. It has been suggested that both brain nerve conduction velocity and PNCV are positively correlated with intelligence (Reed, 1984) and that heritable differences in NCV may

  9. Strategic Plans to Promote Head and Neck Cancer Translational Research Within the Radiation Therapy Oncology Group: A Report From the Translational Research Program

    International Nuclear Information System (INIS)

    Chung, Christine H.; Wong, Stuart; Ang, K. Kian; Hammond, Elizabeth H.; Dicker, Adam P.; Harari, Paul M.; Le, Quynh-Thu

    2007-01-01

    Head and neck cancer is the fifth most common cancer in the United States, with an overall survival rate of approximately 40-50%. In an effort to improve patient outcomes, research efforts designed to maximize benefit and reduce toxicities of therapy are in progress. Basic research in cancer biology has accelerated this endeavor and provided preclinical data and technology to support clinically relevant advances in early detection, prognostic and predictive biomarkers. Recent completion of the Human Genome Project has promoted the rapid development of novel 'omics' technologies that allow more broad based study from a systems biology perspective. However, clinically relevant application of resultant gene signatures to clinical trials within cooperative groups has advanced slowly. In light of the large numbers of variables intrinsic to biomarker studies, validation of preliminary data for clinical implementation presents a significant challenge and may only be realized with large trials that involve significant patient numbers. The Radiation Therapy Oncology Group (RTOG) Head and Neck Cancer Translational Research Program recognizes this problem and brings together three unique features to facilitate this research: (1) availability of large numbers of clinical specimens from homogeneously treated patients through multi-institutional clinical trials; (2) a team of physicians, scientists, and staff focused on patient-oriented head-and-neck cancer research with the common goal of improving cancer care; and (3) a funding mechanism through the RTOG Seed Grant Program. In this position paper we outline strategic plans to further promote translational research within the framework of the RTOG

  10. Analysis of the health of a group exposed to low doses of ionizing radiation; Analisis de salud en un grupo expuesto a dosis bajas de radiaciones ionizantes

    Energy Technology Data Exchange (ETDEWEB)

    Diaz Ledesma, F [Servicio Medico de Tecnatom, SA Madrid (Spain); Crespo, H [Hospital Gregorio Maranon de Madrid, Madrid (Spain)

    1997-11-01

    In order to evaluate the effects of exposure to low radiation doses, the health status of professional staff exposed to ionizing radiation is investigated. Based on archived material of medical and radiation exposure records taken over a time span of 13 years, a variety of medical parameters are explored. Findings of surveys made are given. (author). 1 fig.

  11. Sodium Velocity Maps on Mercury

    Science.gov (United States)

    Potter, A. E.; Killen, R. M.

    2011-01-01

    The objective of the current work was to measure two-dimensional maps of sodium velocities on the Mercury surface and examine the maps for evidence of sources or sinks of sodium on the surface. The McMath-Pierce Solar Telescope and the Stellar Spectrograph were used to measure Mercury spectra that were sampled at 7 milliAngstrom intervals. Observations were made each day during the period October 5-9, 2010. The dawn terminator was in view during that time. The velocity shift of the centroid of the Mercury emission line was measured relative to the solar sodium Fraunhofer line corrected for radial velocity of the Earth. The difference between the observed and calculated velocity shift was taken to be the velocity vector of the sodium relative to Earth. For each position of the spectrograph slit, a line of velocities across the planet was measured. Then, the spectrograph slit was stepped over the surface of Mercury at 1 arc second intervals. The position of Mercury was stabilized by an adaptive optics system. The collection of lines were assembled into an images of surface reflection, sodium emission intensities, and Earthward velocities over the surface of Mercury. The velocity map shows patches of higher velocity in the southern hemisphere, suggesting the existence of sodium sources there. The peak earthward velocity occurs in the equatorial region, and extends to the terminator. Since this was a dawn terminator, this might be an indication of dawn evaporation of sodium. Leblanc et al. (2008) have published a velocity map that is similar.

  12. Cognition and Quality of Life After Chemotherapy Plus Radiotherapy (RT) vs. RT for Pure and Mixed Anaplastic Oligodendrogliomas: Radiation Therapy Oncology Group Trial 9402

    International Nuclear Information System (INIS)

    Wang Meihua; Cairncross, Gregory; Shaw, Edward

    2010-01-01

    Purpose: Radiation Therapy Oncology Group 9402 compared procarbazine, lomustine, and vincristine (PCV) chemotherapy plus radiation therapy (PCV + RT) vs. RT alone for anaplastic oligodendroglioma. Here we report longitudinal changes in cognition and quality of life, effects of patient factors and treatments on cognition, quality of life and survival, and prognostic implications of cognition and quality of life. Methods and Materials: Cognition was assessed by Mini Mental Status Examination (MMSE) and quality of life by Brain-Quality of Life (B-QOL). Scores were analyzed for survivors and within 5 years of death. Shared parameter models evaluated MMSE/B-QOL with survival. Results: For survivors, MMSE and B-QOL scores were similar longitudinally and between treatments. For those who died, MMSE scores remained stable initially, whereas B-QOL slowly declined; both declined rapidly in the last year of life and similarly between arms. In the aggregate, scores decreased over time (p = 0.0413 for MMSE; p = 0.0016 for B-QOL) and were superior with age <50 years (p < 0.001 for MMSE; p = 0.0554 for B-QOL) and Karnofsky Performance Score (KPS) 80-100 (p < 0.001). Younger age and higher KPS were associated with longer survival. After adjusting for patient factors and drop-out, survival was longer after PCV + RT (HR = 0.66, 95% CI = 0.49-0.9, p = 0.0084; HR = 0.74, 95% CI = 0.54-1.01, p = 0.0592) in models with MMSE and B-QOL. In addition, there were no differences in MMSE and B-QOL scores between arms (p = 0.4752 and p = 0.2767, respectively); higher scores predicted longer survival. Conclusion: MMSE and B-QOL scores held steady in the upper range in both arms for survivors. Younger, fitter patients had better MMSE and B-QOL and longer survival.

  13. Phase 2 Study of Temozolomide-Based Chemoradiation Therapy for High-Risk Low-Grade Gliomas: Preliminary Results of Radiation Therapy Oncology Group 0424

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, Barbara J., E-mail: barbara.fisher@lhsc.on.ca [London Regional Cancer Program, London, Ontario (Canada); Hu, Chen [Radiation Therapy Oncology Group-Statistical Center, Philadelphia, Pennsylvania (United States); Macdonald, David R. [London Regional Cancer Program, London, Ontario (Canada); Lesser, Glenn J. [Wake Forest University Baptist Medical Center, Winston-Salem, North Carolina (United States); Coons, Stephen W. [Barrow Neurological Institute, Phoenix, Arizona (United States); Brachman, David G. [Arizona Oncology Services Foundation, Phoenix, Arizona (United States); Ryu, Samuel [Henry Ford Hospital, Detroit, Michigan (United States); Werner-Wasik, Maria [Thomas Jefferson University Hospital Center, Philadelphia, Pennsylvania (United States); Bahary, Jean-Paul [Centre Hospitalier de l' Université de Montréal-Notre Dame, Montreal, Quebec (Canada); Liu, Junfeng [GCE Solutions, Inc., Bloomington, Illinois (United States); Chakravarti, Arnab [The Ohio State University, The James, Columbus, Ohio (United States); Mehta, Minesh [University of Maryland Medical Systems, Baltimore, Maryland (United States)

    2015-03-01

    Purpose: Radiation Therapy Oncology Group (RTOG) 0424 was a phase 2 study of a high-risk low-grade glioma (LGG) population who were treated with temozolomide (TMZ) and radiation therapy (RT), and outcomes were compared to those of historical controls. This study was designed to detect a 43% increase in median survival time (MST) from 40.5 to 57.9 months and a 20% improvement in 3-year overall survival (OS) rate from 54% to 65% at a 10% significance level (1-sided) and 96% power. Methods and Materials: Patients with LGGs with 3 or more risk factors for recurrence (age ≥40 years, astrocytoma histology, bihemispherical tumor, preoperative tumor diameter of ≥6 cm, or a preoperative neurological function status of >1) were treated with RT (54 Gy in 30 fractions) and concurrent and adjuvant TMZ. Results: From 2005 to 2009, 129 evaluable patients (75 males and 54 females) were accrued. Median age was 49 years; 91% had a Zubrod score of 0 or 1; and 69%, 25%, and 6% of patients had 3, 4, and 5 risk factors, respectively. Patients had median and minimum follow-up examinations of 4.1 years and 3 years, respectively. The 3-year OS rate was 73.1% (95% confidence interval: 65.3%-80.8%), which was significantly improved compared to that of prespecified historical control values (P<.001). Median survival time has not yet been reached. Three-year progression-free survival was 59.2%. Grades 3 and 4 adverse events occurred in 43% and 10% of patients, respectively. One patient died of herpes encephalitis. Conclusions: The 3-year OS rate of 73.1% for RTOG 0424 high-risk LGG patients is higher than that reported for historical controls (P<.001) and the study-hypothesized rate of 65%.

  14. Failure patterns by prognostic group as determined by recursive partitioning analysis (RPA) of 1547 on four radiation therapy oncology group studies in operable non-small cell lung cancer (NSCLC)

    International Nuclear Information System (INIS)

    Komaki, Ritsuko; Scott, Charles B.; Byhardt, Roger W.; Emami, Bahman; Asbell, Sucha O.; Russell, Anthony H.; Roach, Mack; Urtasun, Raul C.; Gaspar, Laurie E.

    1997-01-01

    Purpose: To identify groups of patients who might benefit from more aggressive systemic or local treatment based on failure patterns when unresectable NSCLC was treated by radiation therapy alone. Methods: 1547 patients from 4 RTOG trials treated by RT alone were analyzed for the patterns of first failure by PRA class which was defined by prognostic factors, e.g., stage, KPS, weight loss, pleural effusion, age. All patients were AJCC stage II, IIIA or IIIB with KPS of at least 50 and n previous radiotherapy or chemotherapy for their NSCLC. Progressions in the primary (within irradiated fields), thorax (outside irradiated area), brain and distant metastasis other than brain were compared (two-sided) for each failure category by RPA. Results: The RPA classes are four distinct subgroups that had significantly different median survivals of 12.6, 8.3, 6.2 and 3.3 months for classes I, II, III and IV respectively (all groups p=0.0002). Pair comparison showed that RPA I vs IV p<0.0001, I vs III p=0.006, II vs IV p<0.0001, and III vs IV p=0.06. Conclusions: These results suggest the burden of disease and physiologic compromise in class IV patients are sufficient to cause death before specific sites of failure can be discerned. Site specific treatment strategies (intensive local therapy, combination chemotherapy, prophylactic cranial irradiation) may lead to improved outcome in class I and II, but are unlikely to alter outcome in class III and IV

  15. Introduction to vector velocity imaging

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Udesen, Jesper; Hansen, Kristoffer Lindskov

    Current ultrasound scanners can only estimate the velocity along the ultrasound beam and this gives rise to the cos() factor on all velocity estimates. This is a major limitation as most vessels are close to perpendicular to the beam. Also the angle varies as a function of space and time making ...

  16. The impact of concurrent granulocyte macrophage-colony stimulating factor on radiation-induced mucositis in head and neck cancer patients: A double-blind placebo-controlled prospective Phase III study by Radiation Therapy Oncology Group 9901

    International Nuclear Information System (INIS)

    Ryu, Janice K.; Swann, Suzanne; LeVeque, Francis; Scarantino, Charles W.; Johnson, Darlene J.; Chen, Allan; Fortin, Andre; Pollock, JonDavid; Kim, Harold; Ang, Kian K.

    2007-01-01

    Purpose: Based on early clinical evidence of potential mucosal protection by granulocyte-macrophage colony stimulating factor (GM-CSF), the Radiation Therapy Oncology Group conducted a double-blind, placebo-controlled, randomized study to test the efficacy and safety of GM-CSF in reducing the severity and duration of mucosal injury and pain (mucositis) associated with curative radiotherapy (RT) in head-and-neck cancer patients. Methods and Materials: Eligible patients included those with head-and-neck cancer with radiation ports encompassing >50% of oral cavity and/or oropharynx. Standard RT ports were used to cover the primary tumor and regional lymphatics at risk in standard fractionation to 60-70 Gy. Concurrent cisplatin chemotherapy was allowed. Patients were randomized to receive subcutaneous injection of GM-CSF 250 μg/m 2 or placebo 3 times a week. Mucosal reaction was assessed during the course of RT using the National Cancer Institute Common Toxicity Criteria and the protocol-specific scoring system. Results: Between October 2000 and September 2002, 130 patients from 36 institutions were accrued. Nine patients (7%) were excluded from the analysis, 3 as a result of drug unavailability. More than 80% of the patients participated in the quality-of-life endpoint of this study. The GM-CSF did not cause any increase in toxicity compared with placebo. There was no statistically significant difference in the average mean mucositis score in the GM-CSF and placebo arms by a t test (p = 0.4006). Conclusion: This placebo-controlled, randomized study demonstrated no significant effect of GM-CSF given concurrently compared with placebo in reducing the severity or duration of RT-induced mucositis in patients undergoing definitive RT for head-and-neck cancer

  17. Multicenter Study of Carbon-Ion Radiation Therapy for Mucosal Melanoma of the Head and Neck: Subanalysis of the Japan Carbon-Ion Radiation Oncology Study Group (J-CROS) Study (1402 HN)

    Energy Technology Data Exchange (ETDEWEB)

    Koto, Masashi, E-mail: koto.masashi@qst.go.jp [Hospital of the National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Sciences and Technology, Chiba (Japan); Demizu, Yusuke [Department of Radiology, Hyogo Ion Beam Medical Center, Tatsuno (Japan); Saitoh, Jun-ichi [Gunma University Heavy Ion Medical Center, Maebashi (Japan); Suefuji, Hiroaki [Ion Beam Therapy Center, SAGA-HIMAT Foundation, Tosu (Japan); Tsuji, Hiroshi [Hospital of the National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Sciences and Technology, Chiba (Japan); Okimoto, Tomoaki [Department of Radiology, Hyogo Ion Beam Medical Center, Tatsuno (Japan); Ohno, Tatsuya [Gunma University Heavy Ion Medical Center, Maebashi (Japan); Shioyama, Yoshiyuki [Ion Beam Therapy Center, SAGA-HIMAT Foundation, Tosu (Japan); Takagi, Ryo [Hospital of the National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Sciences and Technology, Chiba (Japan); Nemoto, Kenji [Department of Radiation Oncology, Yamagata University Faculty of Medicine, Yamagata (Japan); Nakano, Takashi [Gunma University Heavy Ion Medical Center, Maebashi (Japan); Kamada, Tadashi [Hospital of the National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Sciences and Technology, Chiba (Japan)

    2017-04-01

    Purpose: To evaluate the efficacy and safety of carbon-ion radiation therapy (RT) for mucosal melanoma of the head and neck (MMHN) in the Japan Carbon-Ion Radiation Oncology Study Group study. Methods and Materials: Patients with MMHN with N0-1M0 status who were treated with carbon-ion RT at 4 institutions in Japan between November 2003 and December 2014 were analyzed retrospectively. Two hundred sixty patients (male, 111; female, 149; median age, 68 years) with histologically proven MMHN were enrolled. Results: Primary sites included the nasal cavity in 178 patients, paranasal sinuses in 43, oral cavity in 27, and pharynx in 12. Eighty-six patients had T3 tumors, 147 had T4a tumors, and 27 had T4b tumors. Two hundred fifty-one patients were diagnosed with N0 disease, and 9 with N1 disease. The median total dose and number of fractions were 57.6 Gy RBE (relative biological effectiveness) and 16, respectively. Chemotherapy including dimethyl traizeno imidazole carboxamide was used concurrently in 129 patients. The median follow-up duration was 22 months (range, 1-132 months). The 2-year overall survival and local control rates were 69.4% and 83.9%, respectively. Multivariate analysis showed that gross tumor volume and concurrent chemotherapy were significant prognostic factors for overall survival. Grade 3 and grade 4 late morbidities were observed in 27 and 7 patients (5 developed ipsilateral blindness, 1 mucosal ulcer, and 1 second malignant disease in the irradiated volume), respectively. No patients developed grade 5 late morbidities. Conclusion: Carbon-ion RT is a promising treatment option for MMHN.

  18. Diffraction imaging and velocity analysis using oriented velocity continuation

    KAUST Repository

    Decker, Luke

    2014-08-05

    We perform seismic diffraction imaging and velocity analysis by separating diffractions from specular reflections and decomposing them into slope components. We image slope components using extrapolation in migration velocity in time-space-slope coordinates. The extrapolation is described by a convection-type partial differential equation and implemented efficiently in the Fourier domain. Synthetic and field data experiments show that the proposed algorithm is able to detect accurate time-migration velocities by automatically measuring the flatness of events in dip-angle gathers.

  19. Postmastectomy Radiation Therapy in Women with T1-T2 Tumors and 1 to 3 Positive Lymph Nodes: Analysis of the Breast International Group 02-98 Trial.

    Science.gov (United States)

    Zeidan, Youssef H; Habib, Joyce G; Ameye, Lieveke; Paesmans, Marianne; de Azambuja, Evandro; Gelber, Richard D; Campbell, Ian; Nordenskjöld, Bo; Gutiérez, Jorge; Anderson, Michael; Lluch, Ana; Gnant, Michael; Goldhirsch, Aron; Di Leo, Angelo; Joseph, David J; Crown, John; Piccart-Gebhart, Martine; Francis, Prudence A

    2018-06-01

    To analyze the impact of postmastectomy radiation therapy (PMRT) for patients with T1-T2 tumors and 1 to 3 positive lymph nodes enrolled on the Breast International Group (BIG) 02-98 trial. The BIG 02-98 trial randomized patients to receive adjuvant anthracycline with or without taxane chemotherapy. Delivery of PMRT was nonrandomized and performed according to institutional preferences. The present analysis was performed on participants with T1-T2 breast cancer and 1 to 3 positive lymph nodes who had undergone mastectomy and axillary nodal dissection. The primary objective of the present study was to examine the effect of PMRT on risk of locoregional recurrence (LRR), breast cancer-specific survival, and overall survival. We identified 684 patients who met the inclusion criteria and were included in the analysis, of whom 337 (49%) had received PMRT. At 10 years, LRR risk was 2.5% in the PMRT group and 6.5% in the no-PMRT group (hazard ratio 0.29, 95% confidence interval 0.12-0.73; P = .005). Lower LRR after PMRT was noted for patients randomized to receive adjuvant chemotherapy with no taxane (10-year LRR: 3.4% vs 9.1%; P = .02). No significant differences in breast cancer-specific survival (84.3% vs 83.9%) or overall survival (81.7% vs 78.3%) were observed according to receipt of PMRT. Our analysis of the BIG 02-98 trial shows excellent outcomes in women with T1-T2 tumors and 1 to 3 positive lymph nodes found in axillary dissection. Although PMRT improved LRR in this cohort, the number of events remained low at 10 years. In all groups, 10-year rates of LRR were relatively low compared with historical studies. As such, the use of PMRT in women with 1 to 3 positive nodes should be tailored to individual patient risks. Copyright © 2018 Elsevier Inc. All rights reserved.

  20. Synthesis of a hollow fiber type porous chelating resin containing the amide oxime group by radiation induced graft polymerization for the uranium recovery

    International Nuclear Information System (INIS)

    Hori, Takahiro; Saito, Kyoichi; Furusaki, Shintaro; Sugo, Takanobu; Okamoto, Jiro.

    1986-01-01

    A hollow fiber type porous chelating resin containing amide oxime as a functional group was synthesized and used as an adsorbent for the recovery of uranium. Hollow fiber type porous polyethylene was used as a base polymer. Acrylonitrile was grafted onto it by the radiation-induced graft polymerization. By changing the reaction time, four kinds of graft polymer were obtained. The degree of grafting ranged from 79 % to 127 %. Each resin was soaked in hydroxylamine solution, and the cyano group was converted to amide oxime group. By elemental analysis, the amount of nitrogen introduced on the graft polymer resin in amidoximation was determined to range from 4.3 mmol to 8.5 mmol per 1 g of base polymer. Most of the nitrogen is considered to belong to the amide oxime group. The pore radius, which was initially distributed broadly from about 500 A to 10000 A for the base polymer, was changed to about 1000 A with narrow distribution by the grafting. The pore volume was 1.2 ∼ 1.4 cm 3 per 1 gram of the amide oxime resin, which was about half of that of the initial base polymer. But the pore volume per 1 g base polymer of the amide oxime resin increased with an increase in the grafting degree, e.g. 4.5 cm 3 /g base polymer at 127 % of grafting degree. Specific surface area, which was 30 m 2 /g in base polymer, decreased with an increase in the grafting degree, e.g. 15 m 2 /g at 127 % of grafting degree. Both the amounts of the adsorbed hydrochloric acid and the adsorbed copper were about 1.5 times of the amount of nitrogen introduced in the amidoximation. The reason is considered to be caused by the formation of hydroxamic acid and amide from the measurements of the IR spectra. The amount of uranium adsorbed on the resin was 64 % of the amount of nitrogen introduced in the amidoximation. (author)

  1. RADHEAT-V3, a code system for generating coupled neutron and gamma-ray group constants and analyzing radiation transport

    International Nuclear Information System (INIS)

    Koyama, Kinji; Taji, Yukichi; Miyasaka, Shun-ichi; Minami, Kazuyoshi.

    1977-07-01

    The modular code system RADHEAT is for producing coupled multigroup neutron and gamma-ray cross section sets, analyzing the neutron and gamma-ray transport, and calculating the energy deposition and atomic displacements due to these radiations in a nuclear reactor or shield. The basic neutron cross sections and secondary gamma-ray production data are taken from ENDF/B and POPOP4 libraries respectively. The system (1) generates multigroup neutron cross sections, energy deposition coefficients and atomic displacement factors due to neutron reactions, (2) generates multigroup gamma-ray cross sections and energy transfer coefficients, (3) generates secondary gamma-ray production cross sections, (4) combines these cross sections into the coupled set, (5) outputs and updates the multigroup cross section libraries in convenient formats for other transport codes, (6) analyzes the neutron and gamma-ray transport and calculates the energy deposition and the number density of atomic displacements in a medium, (7) collapses the cross sections to a broad-group structure, by option, using the weighting functions obtained by one-dimensional transport calculation, and (8) plots, by option, multigroup cross sections, and neutron and gamma-ray distributions. Definitions of the input data required in various options of the code system are also given. (auth.)

  2. Ultra-rapid high dose irradiation schedules for the palliation of brain metastases: final results of the first two studies by the radiation therapy oncology group

    International Nuclear Information System (INIS)

    Borgelt, B.; Gelber, R.; Larson, M.; Hendrickson, F.; Griffin, T.; Rother, R.

    1981-01-01

    Between January, 1971, and February, 1976, the Radiation Therapy Oncology Group entered 1902 evaluable patients into two sequential Phase III national cooperative trials to study the effectiveness of different time dose radiotherapy schemes on the palliation of patients with brain metastases. Each trial included an optional arm into which patients were randomized to receive 1000 rad/1 fraction (26 patients, First study) or 1200 rad/2 fractions (33 patients, Second study). Comparisons were made with 143 control patients randomized by the same participating institutions to receive a more protracted course of irradiation (2000, 3000 or 4000 rad/1-4wks). Response of patients receiving ultra-rapid treatment, as assessed by the percent who had improvement in neurologic function, was comparable to that of patients receiving the more protracted schedules. Promptness of neurologic function improvement, treatment morbidity and median survival were also comparable to those of patients receiving 2000 to 4000 rad. However, the duration of improvement, time to progression of neurologic status and rate of complete disappearance of neurologic symptoms were generally less for those patients who received 1000 or 1200 rad. These results suggest that ultra-rapid, high dose irradiation schedules may not be so effective as higher dose schedules in the palliation of patients with brain metastases

  3. INDAR: a computer code for the calculation of critical group radiation exposure from routine discharges of radioactivity to seas and estuaries - description and users' guide

    International Nuclear Information System (INIS)

    Maul, P.R.; Wilmott, S.

    1988-12-01

    The computer program INDAR enables detailed estimates to be made of critical group radiation exposure arising from routine discharges of radioactivity for coastal sites where the discharge is close to the shore and the shoreline is reasonably straight, and for estuarine sites where radioactivity is rapidly mixed across the width of the estuary. Important processes which can be taken into account include the turbulence generated by the discharge, the effects of a sloping sea bed and the variation with time of the lateral dispersion coefficient. The significance of the timing of discharges can also be assessed. INDAR uses physically meaningful hydrographic parameters directly. For most sites the most important exposure pathways are seafood consumption, external exposure over estuarine sediments and beaches, and the handling of fishing gear. As well as for these primary pathways, INDAR enables direct calculations to be made for some additional exposure pathways. The secondary pathways considered are seaweed consumption, swimming, the handling of materials other than fishing gear and the inhalation of activity. (author)

  4. Protein Kinase A RI-α Predicts for Prostate Cancer Outcome: Analysis of Radiation Therapy Oncology Group Trial 86-10

    International Nuclear Information System (INIS)

    Khor, Li-Yan; Bae, Kyounghwa; Al-Saleem, Tahseen; Hammond, Elizabeth H.; Grignon, David J.; Sause, William T.; Pilepich, Miljenko V.; Okunieff, Paul P.; Sandler, Howard M.; Pollack, Alan

    2008-01-01

    Purpose: The RI-α regulatory subunit of protein kinase A type 1 (PKA) is constitutively overexpressed in human cancer cell lines and is associated with active cell growth and neoplastic transformation. This report examined the association between PKA expression and the endpoints of biochemical failure (BF), local failure (LF), distant metastasis (DM), cause-specific mortality (CSM), and overall mortality in men treated with radiotherapy, with or without short-term androgen deprivation in Radiation Therapy Oncology Group trial 86-10. Methods and Materials: Pretreatment archival diagnostic tissue samples from 80 patients were stained for PKA by immunohistochemical methods from a parent cohort of 456 cases. PKA intensity was scored manually and by image analysis. The Cox proportional hazards model for overall mortality and Fine and Gray's regression models for CSM, DM, LF and BF were then applied to determine the relationship of PKA expression to the endpoints. Results: The pretreatment characteristics of the missing and determined PKA groups were not significantly different. On univariate analyses, a high PKA staining intensity was associated with BF (image analysis, continuous variable, p = 0.022), LF (image analysis, dichotomized variable, p = 0.011), CSM (manual analysis, p = 0.037; image analysis, continuous, p = 0.014), and DM (manual analysis, p = 0.029). On multivariate analyses, the relationships to BF (image analysis, continuous, p = 0.03), LF (image analysis, dichotomized, p = 0.002), and DM remained significant (manual analysis, p = 0.018). In terms of CSM, a trend toward an association was seen (manual analysis, p = 0.08; image analysis, continuous, p = 0.09). Conclusion: PKA overexpression was significantly related to patient outcome and is a potentially useful biomarker for identifying high-risk prostate cancer patients who might benefit from a PKA knockdown strategy

  5. Fractals control in particle's velocity

    International Nuclear Information System (INIS)

    Zhang Yongping; Liu Shutang; Shen Shulan

    2009-01-01

    Julia set, a fractal set of the literature of nonlinear physics, has significance for the engineering applications. For example, the fractal structure characteristics of the generalized M-J set could visually reflect the change rule of particle's velocity. According to the real world requirement, the system need show various particle's velocity in some cases. Thus, the control of the nonlinear behavior, i.e., Julia set, has attracted broad attention. In this work, an auxiliary feedback control is introduced to effectively control the Julia set that visually reflects the change rule of particle's velocity. It satisfies the performance requirement of the real world problems.

  6. Southern high-velocity stars

    International Nuclear Information System (INIS)

    Augensen, H.J.; Buscombe, W.

    1978-01-01

    Using the model of the Galaxy presented by Eggen, Lynden-Bell and Sandage (1962), plane galactic orbits have been calculated for 800 southern high-velocity stars which possess parallax, proper motion, and radial velocity data. The stars with trigonometric parallaxes were selected from Buscombe and Morris (1958), supplemented by more recent spectroscopic data. Photometric parallaxes from infrared color indices were used for bright red giants studied by Eggen (1970), and for red dwarfs for which Rodgers and Eggen (1974) determined radial velocities. A color-color diagram based on published values of (U-B) and (B-V) for most of these stars is shown. (Auth.)

  7. Report of the work-group derived from the permanent radioprotection expert Group on the desirable evolutions for the functions and training of persons with expertise in radiation protection

    International Nuclear Information System (INIS)

    2010-01-01

    This report first discusses the issues of training in radiation protection within the French national context by distinguishing training in relationship with workers' radiation protection (internal training in radiation protection as foreseen in the French Work Code, training in the industrial field, training in the field of radioactive material transportation, training of the person with expertise in radiation protection or PCR), and training in relationship with patient radiation protection (training of the person specialised in medical radio-physics, training in patient radiation protection). It describes the situation and evolution perspectives at the European level by addressing the situation in different countries (Great-Britain, Belgium, Switzerland), the content of the 96/29/Euratom directive, the current evolutions in Europe (European platform EUTERP, European programs ENETRAP, transposition of the 2006-123-CE directive, the 2005-36-CE directive and its revision), and some international aspects. The authors discuss strengths and weaknesses of the person with expertise in radiation protection (PCR), and state reflections and recommendations regarding the evolution of the present PCR arrangement

  8. EVOLUTION OF ROTATIONAL VELOCITIES OF A-TYPE STARS

    International Nuclear Information System (INIS)

    Yang Wuming; Bi Shaolan; Tian Zhijia; Meng Xiangcun

    2013-01-01

    The equatorial velocity of A-type stars undergoes an acceleration in the first third of the main sequence (MS) stage, but the velocity decreases as if the stars were not undergoing any redistribution of angular momentum in the external layers in the last stage of the MS phase. Our calculations show that the acceleration and the decrease of the equatorial velocity can be reproduced by the evolution of the differential rotation zero-age MS model with the angular momentum transport caused by hydrodynamic instabilities during the MS stage. The acceleration results from the fact that the angular momentum stored in the interiors of the stars is transported outward. In the last stage, the core and the radiative envelope are uncoupling, and the rotation of the envelope is a quasi-solid rotation; the uncoupling and the expansion of the envelope indicate that the decrease of the equatorial velocity approximately follows the slope for the change in the equatorial velocity of the model without any redistribution of angular momentum. When the fractional age 0.3 ∼ MS ∼< 0.5, the equatorial velocity remains almost constant for stars whose central density increases with age in the early stage of the MS phase, while the velocity decreases with age for stars whose central density decreases with age in the early stage of the MS phase.

  9. Sound Velocity in Soap Foams

    International Nuclear Information System (INIS)

    Wu Gong-Tao; Lü Yong-Jun; Liu Peng-Fei; Li Yi-Ning; Shi Qing-Fan

    2012-01-01

    The velocity of sound in soap foams at high gas volume fractions is experimentally studied by using the time difference method. It is found that the sound velocities increase with increasing bubble diameter, and asymptotically approach to the value in air when the diameter is larger than 12.5 mm. We propose a simple theoretical model for the sound propagation in a disordered foam. In this model, the attenuation of a sound wave due to the scattering of the bubble wall is equivalently described as the effect of an additional length. This simplicity reasonably reproduces the sound velocity in foams and the predicted results are in good agreement with the experiments. Further measurements indicate that the increase of frequency markedly slows down the sound velocity, whereas the latter does not display a strong dependence on the solution concentration

  10. Settling velocities in batch sedimentation

    International Nuclear Information System (INIS)

    Fricke, A.M.; Thompson, B.E.

    1982-10-01

    The sedimentation of mixtures containing one and two sizes of spherical particles (44 and 62 μm in diameter) was studied. Radioactive tracing with 57 Co was used to measure the settling velocities. The ratio of the settling velocity U of uniformly sized particles to the velocity predicted to Stokes' law U 0 was correlated to an expression of the form U/U 0 = epsilon/sup α/, where epsilon is the liquid volume fraction and α is an empirical constant, determined experimentally to be 4.85. No effect of viscosity on the ratio U/U 0 was observed as the viscosity of the liquid medium was varied from 1x10 -3 to 5x10 -3 Pa.s. The settling velocities of particles in a bimodal mixture were fit by the same correlation; the ratio U/U 0 was independent of the concentrations of different-sized particles

  11. A role for radiotherapy in neuropathic bone pain: preliminary response rates from a prospective trial (Trans-Tasman Radiation Oncology Group, TROG 96.05)

    International Nuclear Information System (INIS)

    Roos, Daniel E.; O'Brien, Peter C.; Smith, Jennifer G.; Spry, Nigel A.; Hoskin, Peter J.; Burmeister, Bryan H.; Turner, Sandra L.; Bernshaw, David M.

    2000-01-01

    Purpose: Radiotherapy (RT) has a proven role in palliation of pain from bone metastases with numerous randomized trials obtaining response rates (RRs) of typically 70-80% regardless of the fractionation employed. However RT for neuropathic bone pain (NBP), i.e., pain with a radiating cutaneous component due to compression/irritation of nerves by tumor has not previously been studied, and its role is thus uncertain. Methods and Materials: In February 1996, the Trans-Tasman Radiation Oncology Group (TROG) initiated a multicenter randomized trial comparing a single 8 Gy fraction with 20 Gy in 5 fractions for NBP with an accrual target of 270. Formal interim analyses were planned at 90 and 180 patients. The 90th patient was accrued in June 1998, and data from the first interim analysis with both arms combined form the basis of this report. Results: Forty-four patients were randomized to a single 8 Gy, 46 to 20 Gy in 5 fractions. The commonest primary sites were prostate (34%), lung (28%) and breast (10%). Median age was 68 years (range 37-89). The index site was spine (86%), rib (13%), base of skull (1%). On an intention-to-treat basis, the overall RR was 53/90 = 59% (95% CI = 48-69%), with 27% achieving a complete response and 32% a partial response. The overall RR for eligible patients was 49/81 = 60% (95% CI = 49-71%) with 27% and 33% achieving complete and partial responses respectively. Estimated median time to treatment failure was 3.2 months (95% CI = 2.1-5.1 months), with estimated median survival of 5.1 months (95% CI = 4.2-7.2 months). To date, six spinal cord/cauda equina compressions and four new or progressive pathological fractures have been detected at the index site after randomization, although one cord compression occurred before radiotherapy was planned to commence. In February 1999, the Independent Data Monitoring Committee strongly recommended continuation of the trial. Conclusion: Although these results are preliminary, it seems clear that there

  12. Neurocognitive outcome in brain metastases patients treated with accelerated-fractionation vs. accelerated-hyperfractionated radiotherapy: an analysis from Radiation Therapy Oncology Group Study 91-04

    International Nuclear Information System (INIS)

    Regine, W.F.; Scott, C.; Murray, K.; Curran, W.

    2001-01-01

    Purpose: To evaluate neurocognitive outcome as measured by the Mini-Mental Status Examination (MMSE) among patients with unresectable brain metastases randomly assigned to accelerated fractionation (AF) vs. accelerated hyperfractionated (AH) whole-brain radiation therapy (WBRT). Methods and Materials: The Radiation Therapy Oncology Group (RTOG) accrued 445 patients with unresectable brain metastases to a Phase III comparison of AH (1.6 Gy b.i.d. to 54.4 Gy) vs. AF (3 Gy q.d. to 30 Gy). All had a KPS of ≥ 70 and a neurologic function status of 0-2. Three hundred fifty-nine patients had MMSEs performed and were eligible for this analysis. Changes in the MMSE were analyzed according to criteria previously defined in the literature. Results: The median survival was 4.5 months for both arms. The average change in MMSE at 2 and 3 months was a drop of 1.4 and 1.1, respectively, in the AF arm as compared to a drop of 0.7 and 1.3, respectively, in the AH arm (p=NS). Overall, 91 patients at 2 months and 23 patients at 3 months had both follow-up MMSE and computed tomography/magnetic resonance imaging documentation of the status of their brain metastases. When an analysis was performed taking into account control of brain metastases, a significant effect on MMSE was observed with time and associated proportional increase in uncontrolled brain metastases. At 2 months, the average change in MMSE score was a drop of 0.6 for those whose brain metastases were radiologically controlled as compared to a drop of 1.9 for those with uncontrolled brain metastases (p=0.47). At 3 months, the average change in MMSE score was a drop of 0.5 for those whose brain metastases were radiologically controlled as compared to a drop of 6.3 for those with uncontrolled brain metastases (p=0.02). Conclusion: Use of AH as compared to AF-WBRT was not associated with a significant difference in neurocognitive function as measured by MMSE in this patient population with unresectable brain metastases and

  13. Radiation pressure acceleration: The factors limiting maximum attainable ion energy

    Energy Technology Data Exchange (ETDEWEB)

    Bulanov, S. S.; Esarey, E.; Schroeder, C. B. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Bulanov, S. V. [KPSI, National Institutes for Quantum and Radiological Science and Technology, Kizugawa, Kyoto 619-0215 (Japan); A. M. Prokhorov Institute of General Physics RAS, Moscow 119991 (Russian Federation); Esirkepov, T. Zh.; Kando, M. [KPSI, National Institutes for Quantum and Radiological Science and Technology, Kizugawa, Kyoto 619-0215 (Japan); Pegoraro, F. [Physics Department, University of Pisa and Istituto Nazionale di Ottica, CNR, Pisa 56127 (Italy); Leemans, W. P. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Physics Department, University of California, Berkeley, California 94720 (United States)

    2016-05-15

    Radiation pressure acceleration (RPA) is a highly efficient mechanism of laser-driven ion acceleration, with near complete transfer of the laser energy to the ions in the relativistic regime. However, there is a fundamental limit on the maximum attainable ion energy, which is determined by the group velocity of the laser. The tightly focused laser pulses have group velocities smaller than the vacuum light speed, and, since they offer the high intensity needed for the RPA regime, it is plausible that group velocity effects would manifest themselves in the experiments involving tightly focused pulses and thin foils. However, in this case, finite spot size effects are important, and another limiting factor, the transverse expansion of the target, may dominate over the group velocity effect. As the laser pulse diffracts after passing the focus, the target expands accordingly due to the transverse intensity profile of the laser. Due to this expansion, the areal density of the target decreases, making it transparent for radiation and effectively terminating the acceleration. The off-normal incidence of the laser on the target, due either to the experimental setup, or to the deformation of the target, will also lead to establishing a limit on maximum ion energy.

  14. Altered velocity processing in schizophrenia during pursuit eye tracking.

    Directory of Open Access Journals (Sweden)

    Matthias Nagel

    Full Text Available Smooth pursuit eye movements (SPEM are needed to keep the retinal image of slowly moving objects within the fovea. Depending on the task, about 50%-80% of patients with schizophrenia have difficulties in maintaining SPEM. We designed a study that comprised different target velocities as well as testing for internal (extraretinal guidance of SPEM in the absence of a visual target. We applied event-related fMRI by presenting four velocities (5, 10, 15, 20°/s both with and without intervals of target blanking. 17 patients and 16 healthy participants were included. Eye movements were registered during scanning sessions. Statistical analysis included mixed ANOVAs and regression analyses of the target velocity on the Blood Oxygen Level Dependency (BOLD signal. The main effect group and the interaction of velocity×group revealed reduced activation in V5 and putamen but increased activation of cerebellar regions in patients. Regression analysis showed that activation in supplementary eye field, putamen, and cerebellum was not correlated to target velocity in patients in contrast to controls. Furthermore, activation in V5 and in intraparietal sulcus (putative LIP bilaterally was less strongly correlated to target velocity in patients than controls. Altered correlation of target velocity and neural activation in the cortical network supporting SPEM (V5, SEF, LIP, putamen implies impaired transformation of the visual motion signal into an adequate motor command in patients. Cerebellar regions seem to be involved in compensatory mechanisms although cerebellar activity in patients was not related to target velocity.

  15. Radiation myelopathy

    International Nuclear Information System (INIS)

    Berlit, P.

    1987-01-01

    After a review of the world literature, the case histories of 43 patients with radiation myelopathy are analyzed. In 1 patient there was a radiation injury of the medulla oblongata, in 2, cervical, in 28, thoracic, and in 12, lumbosacral. In the medulla oblongata lesion an alternans syndrome resulted. The patients with cervical and thoracic radiation myelopathies presented with a Brown-Sequard syndrome, a spinalis anterior syndrome or a transversal syndrome with pyramidal and spinothalamic tract involvement as the most prominent signs. For this group the term 'pyramidal-spinothalamic radiation myelopathy' is proposed. In lumbosacral radiation lesions a pure anterior horn syndrome may lead to spinothalamic tract involvement and the development of a cauda conus syndrome. The clinical presentation of these cases suggests that the location of the radiation lesion is most likely the region of the conus medullaris. The most frequent initial symptom was dysesthesia; the patients complained of burning pain or a feeling of coldness. Usually the neurological deficits were progressive, in pyramidal-spinothalamic radiation myelopathy over 12 months in average, in lumbosacral radiation lesions up to 10 years. The latent period between the finish of radiation therapy and the first neurological signs was 8 months (median) in cervical and thoracic myelopathy and 33 months in lumbosacral lesions. For the entire group of 43 patients there was an inverse relationship between the radiation dose (ret) and the latent period. A positive relation could be demonstrated between the age of patients at the time of radiation therapy and the latent period. Patients simultaneously receiving cytostatic drugs presented after a longer latent period than the remaining group. (orig./MG)

  16. Validation and predictive power of radiation therapy oncology group (RTOG) recursive partitioning analysis classes for malignant glioma patients: a report using RTOG 90-06

    International Nuclear Information System (INIS)

    Scott, Charles B.; Scarantino, Charles; Urtasun, Raul; Movsas, Benjamin; Jones, Christopher U.; Simpson, Joseph R.; Fischbach, A. Jennifer; Curran, Walter J.

    1996-01-01

    Background/Purpose: The recursive partitioning analysis (RPA) classes for malignant glioma patients were previously established by Curran et al. (JNCI 85:704-10, 1993) using data on over 1500 patients from the Radiation Therapy Oncology Group (RTOG). The current analysis was to validate the RPA classes on a new dataset (RTOG 90-06) and determine the predictive power of the RPA classes. Patients and Methods: There are six RPA classes for malignant glioma patients that comprise distinct groups of patients with significantly different survival outcome. RTOG 90-06 is a randomized phase III study of 712 patients accrued from 1990 to 1994. The minimum potential follow-up is 18 months. The treatment arms were combined for the purpose of this analysis. There were 84, 13, 105, 240, 150, and 23 patients in the six RPA classes from RTOG 90-06. Results: The median survival times (MST) and two-year survivals for the six RPA classes in RTOG 90-06 are compared to those published by Curran et al. (JNCI 1993). The RPA classes appear in descending order in the following table. The MST and 2-year survivals for the RTOG RPA classes were within 95% confidence intervals of the 90-06 estimates for classes I, III, IV, and V. The RPA classes explained 43% of the variation (squared error loss). By comparison, a model containing only histology explains only 13% of the variation. The RPA classes are statistically distinct with all comparisons exceeding 0.0001, except those involving class II. Conclusion: The validity of the model is verified by the reliability of the RPA classes to define distinct groups with respect to survival. Further evidence is given by prediction of MST and 2-year survival for all classes except class II. The RPA classes explained a good portion of the variation in the data. RPA class II did not perform well which may be an artifact of the small sample size or an indication that this class is not distinct. The validation of the RPA classes attests to their usefulness as

  17. Validation and predictive power of Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis classes for malignant glioma patients: A report using RTOG 90-06

    International Nuclear Information System (INIS)

    Scott, Charles B.; Scarantino, Charles; Urtasun, Raul; Movsas, Benjamin; Jones, Christopher U.; Simpson, Joseph R.; Fischbach, A. Jennifer; Curran, Walter J.

    1998-01-01

    Purpose: The recursive partitioning analysis (RPA) classes for malignant glioma patients were previously established using data on over 1500 patients entered on Radiation Therapy Oncology Group (RTOG) clinical trials. The purpose of the current analysis was to validate the RPA classes with a new dataset (RTOG 90-06), determine the predictive power of the RPA classes, and establish the usefulness of the database norms for the RPA classes. Patients and Methods: There are six RPA classes for malignant glioma patients that comprise distinct groups of patients with significantly different survival outcome. RTOG 90-06 is a randomized Phase III study of 712 patients accrued from 1990 to 1994. The minimum potential follow-up is 18 months. The treatment arms were combined for the purpose of this analysis. There were 84, 13, 105, 240, 150, and 23 patients in the RPA Classes I-VI from RTOG 90-06, respectively. Results: The median survival times (MST) and 2-year survival rates for the six RPA classes in RTOG 90-06 are compared to those previously published. The MST and 2-year survival rates for the RTOG RPA classes were within 95% confidence intervals of the 90-06 estimates for Classes I, III, IV, and V. The RPA classes explained 43% of the variation (squared error loss). By comparison, a Cox model explains 30% of the variation. The RPA classes within RTOG 90-06 are statistically distinct with all comparisons exceeding 0.0001, except those involving Class II. A survival analysis from a prior RTOG study indicated that 72.0 Gy had superior outcome to literature controls; analysis of this data by RPA classes indicates the survival results were not superior to the RTOG database norms. Conclusion: The validity of the model is verified by the reliability of the RPA classes to define distinct groups with respect to survival. Further evidence is given by prediction of MST and 2-year survival for all classes except Class II. The RPA classes explained a good portion of the variation in

  18. Online Wavelet Complementary velocity Estimator.

    Science.gov (United States)

    Righettini, Paolo; Strada, Roberto; KhademOlama, Ehsan; Valilou, Shirin

    2018-02-01

    In this paper, we have proposed a new online Wavelet Complementary velocity Estimator (WCE) over position and acceleration data gathered from an electro hydraulic servo shaking table. This is a batch estimator type that is based on the wavelet filter banks which extract the high and low resolution of data. The proposed complementary estimator combines these two resolutions of velocities which acquired from numerical differentiation and integration of the position and acceleration sensors by considering a fixed moving horizon window as input to wavelet filter. Because of using wavelet filters, it can be implemented in a parallel procedure. By this method the numerical velocity is estimated without having high noise of differentiators, integration drifting bias and with less delay which is suitable for active vibration control in high precision Mechatronics systems by Direct Velocity Feedback (DVF) methods. This method allows us to make velocity sensors with less mechanically moving parts which makes it suitable for fast miniature structures. We have compared this method with Kalman and Butterworth filters over stability, delay and benchmarked them by their long time velocity integration for getting back the initial position data. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  19. Efficacy Endpoints of Radiation Therapy Group Protocol 0247: A Randomized, Phase 2 Study of Neoadjuvant Radiation Therapy Plus Concurrent Capecitabine and Irinotecan or Capecitabine and Oxaliplatin for Patients With Locally Advanced Rectal Cancer

    International Nuclear Information System (INIS)

    Wong, Stuart J.; Moughan, Jennifer; Meropol, Neal J.; Anne, Pramila Rani; Kachnic, Lisa A.; Rashid, Asif; Watson, James C.; Mitchell, Edith P.; Pollock, Jondavid; Lee, R. Jeffrey; Haddock, Michael; Erickson, Beth A.; Willett, Christopher G.

    2015-01-01

    Purpose: To report secondary efficacy endpoints of Radiation Therapy Oncology Group protocol 0247, primary endpoint analysis of which demonstrated that preoperative radiation therapy (RT) with capecitabine plus oxaliplatin achieved a pathologic complete remission prespecified threshold (21%) to merit further study, whereas RT with capecitabine plus irinotecan did not (10%). Methods and Materials: A randomized, phase 2 trial evaluated preoperative RT (50.4 Gy in 1.8-Gy fractions) with 2 concurrent chemotherapy regimens: (1) capecitabine (1200 mg/m 2 /d Monday-Friday) plus irinotecan (50 mg/m 2 /wk × 4); and (2) capecitabine (1650 mg/m 2 /d Monday-Friday) plus oxaliplatin (50 mg/m 2 /wk × 5) for clinical T3 or T4 rectal cancer. Surgery was performed 4 to 8 weeks after chemoradiation, then 4 to 6 weeks later, adjuvant chemotherapy (oxaliplatin 85 mg/m 2 ; leucovorin 400 mg/m 2 ; 5-fluorouracil 400 mg/m 2 ; 5-fluorouracil 2400 mg/m 2 ) every 2 weeks × 9. Disease-free survival (DFS) and overall survival (OS) were estimated univariately by the Kaplan-Meier method. Local–regional failure (LRF), distant failure (DF), and second primary failure (SP) were estimated by the cumulative incidence method. No statistical comparisons were made between arms because each was evaluated individually. Results: A total of 104 patients (median age, 57 years) were treated; characteristics were similar for both arms. Median follow-up for RT with capecitabine/irinotecan arm was 3.77 years and for RT with capecitabine/oxaliplatin arm was 3.97 years. Four-year DFS, OS, LRF, DF, and SP estimates for capecitabine/irinotecan arm were 68%, 85%, 16%, 24%, and 2%, respectively. The 4-year DFS, OS, LRF, DF, and SP failure estimates for capecitabine/oxaliplatin arm were 62%, 75%, 18%, 30%, and 6%, respectively. Conclusions: Efficacy results for both arms are similar to other reported studies but suggest that pathologic complete remission is an unsuitable surrogate for

  20. Efficacy Endpoints of Radiation Therapy Group Protocol 0247: A Randomized, Phase 2 Study of Neoadjuvant Radiation Therapy Plus Concurrent Capecitabine and Irinotecan or Capecitabine and Oxaliplatin for Patients With Locally Advanced Rectal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Stuart J. [Medical College of Wisconsin, Madison, Wisconsin (United States); Moughan, Jennifer [Radiation Therapy Oncology Group Statistical Center, Philadelphia, Pennsylvania (United States); Meropol, Neal J., E-mail: Neal.Meropol@case.edu [University Hospitals Seidman Cancer Center, Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, Ohio (United States); Anne, Pramila Rani [Department of Radiation Oncology and Medical Oncology, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania (United States); Kachnic, Lisa A. [Boston Medical Center, Boston University School of Medicine, Boston, Massachusetts (United States); Rashid, Asif [Department of Pathology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Watson, James C. [Department of Surgical Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Mitchell, Edith P. [Department of Radiation Oncology and Medical Oncology, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania (United States); Pollock, Jondavid [The Schiffler Cancer Center, Wheeling, West Virginia (United States); Lee, R. Jeffrey [Intermountain Medical Center, Murray, Utah (United States); Haddock, Michael [Division of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Erickson, Beth A. [Medical College of Wisconsin, Madison, Wisconsin (United States); Willett, Christopher G. [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States)

    2015-01-01

    Purpose: To report secondary efficacy endpoints of Radiation Therapy Oncology Group protocol 0247, primary endpoint analysis of which demonstrated that preoperative radiation therapy (RT) with capecitabine plus oxaliplatin achieved a pathologic complete remission prespecified threshold (21%) to merit further study, whereas RT with capecitabine plus irinotecan did not (10%). Methods and Materials: A randomized, phase 2 trial evaluated preoperative RT (50.4 Gy in 1.8-Gy fractions) with 2 concurrent chemotherapy regimens: (1) capecitabine (1200 mg/m{sup 2}/d Monday-Friday) plus irinotecan (50 mg/m{sup 2}/wk × 4); and (2) capecitabine (1650 mg/m{sup 2}/d Monday-Friday) plus oxaliplatin (50 mg/m{sup 2}/wk × 5) for clinical T3 or T4 rectal cancer. Surgery was performed 4 to 8 weeks after chemoradiation, then 4 to 6 weeks later, adjuvant chemotherapy (oxaliplatin 85 mg/m{sup 2}; leucovorin 400 mg/m{sup 2}; 5-fluorouracil 400 mg/m{sup 2}; 5-fluorouracil 2400 mg/m{sup 2}) every 2 weeks × 9. Disease-free survival (DFS) and overall survival (OS) were estimated univariately by the Kaplan-Meier method. Local–regional failure (LRF), distant failure (DF), and second primary failure (SP) were estimated by the cumulative incidence method. No statistical comparisons were made between arms because each was evaluated individually. Results: A total of 104 patients (median age, 57 years) were treated; characteristics were similar for both arms. Median follow-up for RT with capecitabine/irinotecan arm was 3.77 years and for RT with capecitabine/oxaliplatin arm was 3.97 years. Four-year DFS, OS, LRF, DF, and SP estimates for capecitabine/irinotecan arm were 68%, 85%, 16%, 24%, and 2%, respectively. The 4-year DFS, OS, LRF, DF, and SP failure estimates for capecitabine/oxaliplatin arm were 62%, 75%, 18%, 30%, and 6%, respectively. Conclusions: Efficacy results for both arms are similar to other reported studies but suggest that pathologic complete remission is an

  1. Focusing on SSI's risk and radiation protection criteria. A report based on discussions in focus groups in Oesthammar and Oskarshamn municipalities

    International Nuclear Information System (INIS)

    Drottz-Sjoeberg, Britt-Marie

    2003-11-01

    The project was a result of the authority's continued work on the 1998 regulations on protection of human health and the environment in final disposal of spent nuclear fuel and nuclear waste. The idea behind the project, to involve persons from the municipalities participating in SKB's site selection investigation in focus group discussions, was that the questions and points of views that emerged in the discussions could serve as a basis for the authority's work of producing general guidelines associated with the regulations. The finished report would then be handed over to an expert group at the authority which answered or commented on the issues raised, and made a report on this to the participating municipalities Oskarshamn and Oesthammar. The result of discussions in two focus groups in Oskarshamn municipality and two in Oesthammar municipality in October 2002 is presented here, together with a presentation of the project's purpose and organisation. The results are presented in three main sections. The first concentrates on radiation and radioactivity since the task in the discussion groups was to attempt to clarify the issues and problems observed in this area in order to contribute to the authority's work of developing the general guidelines. The second section, on understanding of concepts, measurement, risk and safety, illustrates that the frequently asked and 'simple' knowledge related questions are only the tip of the iceberg where many of the participants have also thought about the more complex contexts and the fundamental problems in the risk and safety analysis, its validity and use. The third section of the report focuses primarily on content and information aspects. It provides a number of ideas about how information on current problems and important issues can be improved, how knowledge can be deepened in the site selection municipalities and how working methods in the process can be developed. The report mainly consists of a presentation of the

  2. Focusing on SSI's risk and radiation protection criteria. A report based on discussions in focus groups in Oesthammar and Oskarshamn municipalities

    Energy Technology Data Exchange (ETDEWEB)

    Drottz-Sjoeberg, Britt-Marie [BMD Research (Sweden)

    2003-11-01

    The project was a result of the authority's continued work on the 1998 regulations on protection of human health and the environment in final disposal of spent nuclear fuel and nuclear waste. The idea behind the project, to involve persons from the municipalities participating in SKB's site selection investigation in focus group discussions, was that the questions and points of views that emerged in the discussions could serve as a basis for the authority's work of producing general guidelines associated with the regulations. The finished report would then be handed over to an expert group at the authority which answered or commented on the issues raised, and made a report on this to the participating municipalities Oskarshamn and Oesthammar. The result of discussions in two focus groups in Oskarshamn municipality and two in Oesthammar municipality in October 2002 is presented here, together with a presentation of the project's purpose and organisation. The results are presented in three main sections. The first concentrates on radiation and radioactivity since the task in the discussion groups was to attempt to clarify the issues and problems observed in this area in order to contribute to the authority's work of developing the general guidelines. The second section, on understanding of concepts, measurement, risk and safety, illustrates that the frequently asked and 'simple' knowledge related questions are only the tip of the iceberg where many of the participants have also thought about the more complex contexts and the fundamental problems in the risk and safety analysis, its validity and use. The third section of the report focuses primarily on content and information aspects. It provides a number of ideas about how information on current problems and important issues can be improved, how knowledge can be deepened in the site selection municipalities and how working methods in the process can be developed. The report mainly

  3. Maximal intended velocity training induces greater gains in bench press performance than deliberately slower half-velocity training.

    Science.gov (United States)

    González-Badillo, Juan José; Rodríguez-Rosell, David; Sánchez-Medina, Luis; Gorostiaga, Esteban M; Pareja-Blanco, Fernando

    2014-01-01

    The purpose of this study was to compare the effect on strength gains of two isoinertial resistance training (RT) programmes that only differed in actual concentric velocity: maximal (MaxV) vs. half-maximal (HalfV) velocity. Twenty participants were assigned to a MaxV (n = 9) or HalfV (n = 11) group and trained 3 times per week during 6 weeks using the bench press (BP). Repetition velocity was controlled using a linear velocity transducer. A complementary study (n = 10) aimed to analyse whether the acute metabolic (blood lactate and ammonia) and mechanical response (velocity loss) was different between the MaxV and HalfV protocols used. Both groups improved strength performance from pre- to post-training, but MaxV resulted in significantly greater gains than HalfV in all variables analysed: one-repetition maximum (1RM) strength (18.2 vs. 9.7%), velocity developed against all (20.8 vs. 10.0%), light (11.5 vs. 4.5%) and heavy (36.2 vs. 17.3%) loads common to pre- and post-tests. Light and heavy loads were identified with those moved faster or slower than 0.80 m · s(-1) (∼ 60% 1RM in BP). Lactate tended to be significantly higher for MaxV vs. HalfV, with no differences observed for ammonia which was within resting values. Both groups obtained the greatest improvements at the training velocities (≤ 0.80 m · s(-1)). Movement velocity can be considered a fundamental component of RT intensity, since, for a given %1RM, the velocity at which loads are lifted largely determines the resulting training effect. BP strength gains can be maximised when repetitions are performed at maximal intended velocity.

  4. Interobserver variability in target volume delineation of hepatocellular carcinoma : An analysis of the working group "Stereotactic Radiotherapy" of the German Society for Radiation Oncology (DEGRO).

    Science.gov (United States)

    Gkika, E; Tanadini-Lang, S; Kirste, S; Holzner, P A; Neeff, H P; Rischke, H C; Reese, T; Lohaus, F; Duma, M N; Dieckmann, K; Semrau, R; Stockinger, M; Imhoff, D; Kremers, N; Häfner, M F; Andratschke, N; Nestle, U; Grosu, A L; Guckenberger, M; Brunner, T B

    2017-10-01

    Definition of gross tumor volume (GTV) in hepatocellular carcinoma (HCC) requires dedicated imaging in multiple contrast medium phases. The aim of this study was to evaluate the interobserver agreement (IOA) in gross tumor delineation of HCC in a multicenter panel. The analysis was performed within the "Stereotactic Radiotherapy" working group of the German Society for Radiation Oncology (DEGRO). The GTVs of three anonymized HCC cases were delineated by 16 physicians from nine centers using multiphasic CT scans. In the first case the tumor was well defined. The second patient had multifocal HCC (one conglomerate and one peripheral tumor) and was previously treated with transarterial chemoembolization (TACE). The peripheral lesion was adjacent to the previous TACE site. The last patient had an extensive HCC with a portal vein thrombosis (PVT) and an inhomogeneous liver parenchyma due to cirrhosis. The IOA was evaluated according to Landis and Koch. The IOA for the first case was excellent (kappa: 0.85); for the second case moderate (kappa: 0.48) for the peripheral tumor and substantial (kappa: 0.73) for the conglomerate. In the case of the peripheral tumor the inconsistency is most likely explained by the necrotic tumor cavity after TACE caudal to the viable tumor. In the last case the IOA was fair, with a kappa of 0.34, with significant heterogeneity concerning the borders of the tumor and the PVT. The IOA was very good among the cases were the tumor was well defined. In complex cases, where the tumor did not show the typical characteristics, or in cases with Lipiodol (Guerbet, Paris, France) deposits, IOA agreement was compromised.

  5. Immunohistochemically determined total epidermal growth factor receptor levels not of prognostic value in newly diagnosed glioblastoma multiforme: Report from the Radiation Therapy Oncology Group

    International Nuclear Information System (INIS)

    Chakravarti, Arnab; Seiferheld, Wendy; Tu Xiaoyu; Wang Huijun; Zhang Huazhong; Ang, K. Kian; Hammond, Elizabeth; Curran, Walter; Mehta, Minesh

    2005-01-01

    Purpose: The Radiation Therapy Oncology Group (RTOG) performed an analysis of patterns of immunohistochemically detected total epidermal growth factor receptor (EGFR) protein expression levels and their prognostic significance on archival tissue in newly diagnosed glioblastoma multiforme (GBM) patients from prior prospective RTOG clinical trials. Methods and materials: Patients in this study had been treated on previous RTOG GBM trials (RTOG 7401, 7918, 8302, 8409, 9006, 9305, 9602, and 9806). Tissue microarrays were prepared from 155 patients enrolled in these trials. These specimens were stained using a mouse monoclonal antibody specific for the extracellular binding domain of EGFR to detect total EGFR (including both wild-type phosphorylated and wild-type unphosphorylated isoforms with some cross-reactivity with EGFRvIII). The intensity of total EGFR protein expression was measured by computerized quantitative image analysis using the SAMBA 4000 Cell Image Analysis System. The parameters measured were the mean optical densities over the labeled areas and the staining index, which represents the proportion of stained area relative to the mean stain concentration. Both parameters were correlated with the clinical outcome. Results: No differences in either overall or progression-free survival could be demonstrated by the mean optical density class or mean optical density quartile or the staining index of total EGFR immunostaining among the representative RTOG GBM cases. Conclusion: Total EGFR protein expression levels, as measured immunohistochemically, do not appear to be of prognostic value in newly diagnosed GBM patients. Given the accumulating clinical evidence of the activity of anti-EGFR agents in GBM and the preclinical data suggesting the important role of downstream mediators as effectors of EGFR signaling, the RTOG is conducting additional investigations into the prognostic value of activation patterns of EGFR signaling, both at the level of the receptor

  6. Verification of dosimetric commissioning accuracy of intensity modulated radiation therapy and volumetric modulated arc therapy delivery using task Group-119 guidelines

    Directory of Open Access Journals (Sweden)

    Karunakaran Kaviarasu

    2017-01-01

    Full Text Available Aim: The purpose of this study is to verify the accuracy of the commissioning of intensity-modulated radiation therapy (IMRT and volumetric-modulated arc therapy (VMAT based on the recommendation of the American Association of Physicists in Medicine Task Group 119 (TG-119. Materials and Methods: TG-119 proposes a set of clinical test cases to verify the accuracy of IMRT planning and delivery system. For these test cases, we generated two sets of treatment plans, the first plan using 7–9 IMRT fields and a second plan utilizing two-arc VMAT technique for both 6 MV and 15 MV photon beams. The template plans of TG-119 were optimized and calculated by Varian Eclipse Treatment Planning System (version 13.5. Dose prescription and planning objectives were set according to the TG-119 goals. The point dose (mean dose to the contoured chamber volume at the specified positions/locations was measured using compact (CC-13 ion chamber. The composite planar dose was measured with IMatriXX Evaluation 2D array with OmniPro IMRT Software (version 1.7b. The per-field relative gamma was measured using electronic portal imaging device in a way similar to the routine pretreatment patient-specific quality assurance. Results: Our planning results are compared with the TG-119 data. Point dose and fluence comparison data where within the acceptable confident limit. Conclusion: From the obtained data in this study, we conclude that the commissioning of IMRT and VMAT delivery were found within the limits of TG-119.

  7. Bcl-2 and bax expression and prostate cancer outcome in men treated with radiotherapy in Radiation Therapy Oncology Group protocol 86-10

    International Nuclear Information System (INIS)

    Khor, L.-Y.; De Silvio, Michelle; Li, Rile; McDonnell, Timothy J.; Hammond, M. Elizabeth H.; Sause, William T.; Pilepich, Miljenko V.; Okunieff, Paul; Sandler, Howard M.; Pollack, Alan

    2006-01-01

    Purpose: Bcl-2 and bax are proteins with opposing roles in apoptosis regulation; yet abnormal expression of either has been associated with failure after radiotherapy (RT). In this study we examined bcl-2 and bax expression as predictive markers in men treated with radiotherapy ± androgen deprivation on Radiation Therapy Oncology Group (RTOG) protocol 86-10. Experimental Design: Suitable archival diagnostic tissue was obtained from 119 (26%) patients for bcl-2 analysis and 104 (23%) patients for bax analysis. Cox proportional hazards multivariate analysis was used to determine the relationship of abnormal bcl-2 and bax expression to the end points of local failure, distant metastasis, cause-specific mortality, and overall mortality. Bcl-2 overexpression was classified as any tumor cell cytoplasmic staining and altered bax expression was classified as greater or lesser cytoplasmic staining intensity of tumor cells as compared with adjacent normal prostate epithelium. Results: The study cohort exhibited bcl-2 overexpression in 26% (n = 30) of cases and abnormal bax expression in 47% (n = 49) of cases. A borderline significant relationship was observed between abnormal bax expression and higher Gleason score (p = 0.08). In univariate and multivariate analyses, there was no statistically significant relationship seen between abnormal bcl-2 or bax expression and outcome. Conclusions: Abnormal bcl-2 and bax expression were not related to any of the end points tested. The cohort examined was comprised of patients with locally advanced disease and it is possible that these markers may be of greater value in men with earlier-stage prostate cancer

  8. Gender, Race, and Survival: A Study in Non-Small-Cell Lung Cancer Brain Metastases Patients Utilizing the Radiation Therapy Oncology Group Recursive Partitioning Analysis Classification

    International Nuclear Information System (INIS)

    Videtic, Gregory M.M.; Reddy, Chandana A.; Chao, Samuel T.; Rice, Thomas W.; Adelstein, David J.; Barnett, Gene H.; Mekhail, Tarek M.; Vogelbaum, Michael A.; Suh, John H.

    2009-01-01

    Purpose: To explore whether gender and race influence survival in non-small-cell lung cancer (NSCLC) in patients with brain metastases, using our large single-institution brain tumor database and the Radiation Therapy Oncology Group recursive partitioning analysis (RPA) brain metastases classification. Methods and materials: A retrospective review of a single-institution brain metastasis database for the interval January 1982 to September 2004 yielded 835 NSCLC patients with brain metastases for analysis. Patient subsets based on combinations of gender, race, and RPA class were then analyzed for survival differences. Results: Median follow-up was 5.4 months (range, 0-122.9 months). There were 485 male patients (M) (58.4%) and 346 female patients (F) (41.6%). Of the 828 evaluable patients (99%), 143 (17%) were black/African American (B) and 685 (83%) were white/Caucasian (W). Median survival time (MST) from time of brain metastasis diagnosis for all patients was 5.8 months. Median survival time by gender (F vs. M) and race (W vs. B) was 6.3 months vs. 5.5 months (p = 0.013) and 6.0 months vs. 5.2 months (p = 0.08), respectively. For patients stratified by RPA class, gender, and race, MST significantly favored BFs over BMs in Class II: 11.2 months vs. 4.6 months (p = 0.021). On multivariable analysis, significant variables were gender (p = 0.041, relative risk [RR] 0.83) and RPA class (p < 0.0001, RR 0.28 for I vs. III; p < 0.0001, RR 0.51 for II vs. III) but not race. Conclusions: Gender significantly influences NSCLC brain metastasis survival. Race trended to significance in overall survival but was not significant on multivariable analysis. Multivariable analysis identified gender and RPA classification as significant variables with respect to survival.

  9. A Comparative Evaluation of Normal Tissue Doses for Patients Receiving Radiation Therapy for Hodgkin Lymphoma on the Childhood Cancer Survivor Study and Recent Children's Oncology Group Trials

    International Nuclear Information System (INIS)

    Zhou, Rachel; Ng, Angela; Constine, Louis S.; Stovall, Marilyn; Armstrong, Gregory T.; Neglia, Joseph P.; Friedman, Debra L.; Kelly, Kara; FitzGerald, Thomas J.; Hodgson, David C.

    2016-01-01

    Purpose: Survivors of pediatric Hodgkin lymphoma (HL) are recognized to have an increased risk of delayed adverse health outcomes related to radiation therapy (RT). However, the necessary latency required to observe these late effects means that the estimated risks apply to outdated treatments. We sought to compare the normal tissue dose received by children treated for HL and enrolled in the Childhood Cancer Survivor Study (CCSS) (diagnosed 1970-1986) with that of patients treated in recent Children's Oncology Group (COG) trials (enrolled 2002-2012). Methods and Materials: RT planning data were obtained for 50 HL survivors randomly sampled from the CCSS cohort and applied to computed tomography planning data sets to reconstruct the normal tissue dosimetry. For comparison, the normal tissue dosimetry data were obtained for all 191 patients with full computed tomography–based volumetric RT planning on COG protocols AHOD0031 and AHOD0831. Results: For early-stage patients, the mean female breast dose in the COG patients was on average 83.5% lower than that for CCSS patients, with an absolute reduction of 15.5 Gy. For advanced-stage patients, the mean breast dose was decreased on average by 70% (11.6 Gy average absolute dose reduction). The mean heart dose decreased on average by 22.9 Gy (68.6%) and 17.6 Gy (56.8%) for early- and advanced-stage patients, respectively. All dose comparisons for breast, heart, lung, and thyroid were significantly lower for patients in the COG trials than for the CCSS participants. Reductions in the prescribed dose were a major contributor to these dose reductions. Conclusions: These are the first data quantifying the significant reduction in the normal tissue dose using actual, rather than hypothetical, treatment plans for children with HL. These findings provide useful information when counseling families regarding the risks of contemporary RT.

  10. Verification of Dosimetric Commissioning Accuracy of Intensity Modulated Radiation Therapy and Volumetric Modulated Arc Therapy Delivery using Task Group-119 Guidelines.

    Science.gov (United States)

    Kaviarasu, Karunakaran; Nambi Raj, N Arunai; Hamid, Misba; Giri Babu, A Ananda; Sreenivas, Lingampally; Murthy, Kammari Krishna

    2017-01-01

    The purpose of this study is to verify the accuracy of the commissioning of intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) based on the recommendation of the American Association of Physicists in Medicine Task Group 119 (TG-119). TG-119 proposes a set of clinical test cases to verify the accuracy of IMRT planning and delivery system. For these test cases, we generated two sets of treatment plans, the first plan using 7-9 IMRT fields and a second plan utilizing two-arc VMAT technique for both 6 MV and 15 MV photon beams. The template plans of TG-119 were optimized and calculated by Varian Eclipse Treatment Planning System (version 13.5). Dose prescription and planning objectives were set according to the TG-119 goals. The point dose (mean dose to the contoured chamber volume) at the specified positions/locations was measured using compact (CC-13) ion chamber. The composite planar dose was measured with IMatriXX Evaluation 2D array with OmniPro IMRT Software (version 1.7b). The per-field relative gamma was measured using electronic portal imaging device in a way similar to the routine pretreatment patient-specific quality assurance. Our planning results are compared with the TG-119 data. Point dose and fluence comparison data where within the acceptable confident limit. From the obtained data in this study, we conclude that the commissioning of IMRT and VMAT delivery were found within the limits of TG-119.

  11. Modeling Local Control After Hypofractionated Stereotactic Body Radiation Therapy for Stage I Non-Small Cell Lung Cancer: A Report From the Elekta Collaborative Lung Research Group

    Energy Technology Data Exchange (ETDEWEB)

    Ohri, Nitin, E-mail: ohri.nitin@gmail.com [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Werner-Wasik, Maria [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Grills, Inga S. [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan (United States); Belderbos, Jose [Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam (Netherlands); Hope, Andrew [Department of Radiation Oncology, Princess Margaret Hospital and University of Toronto, Toronto, ON (Canada); Yan Di; Kestin, Larry L. [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan (United States); Guckenberger, Matthias [Department of Radiation Oncology, University of Wuerzburg, Wuerzburg (Germany); Sonke, Jan-Jakob [Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam (Netherlands); Bissonnette, Jean-Pierre [Department of Radiation Oncology, Princess Margaret Hospital and University of Toronto, Toronto, ON (Canada); Xiao, Ying [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States)

    2012-11-01

    Purpose: Hypofractionated stereotactic body radiation therapy (SBRT) has emerged as an effective treatment option for early-stage non-small cell lung cancer (NSCLC). Using data collected by the Elekta Lung Research Group, we generated a tumor control probability (TCP) model that predicts 2-year local control after SBRT as a function of biologically effective dose (BED) and tumor size. Methods and Materials: We formulated our TCP model as follows: TCP = e{sup [BED10-c Asterisk-Operator L-TCD50]/k} Division-Sign (1 + e{sup [BED10-c Asterisk-Operator L-TCD50]/k}), where BED10 is the biologically effective SBRT dose, c is a constant, L is the maximal tumor diameter, and TCD50 and k are parameters that define the shape of the TCP curve. Least-squares optimization with a bootstrap resampling approach was used to identify the values of c, TCD50, and k that provided the best fit with observed actuarial 2-year local control rates. Results: Data from 504 NSCLC tumors treated with a variety of SBRT schedules were available. The mean follow-up time was 18.4 months, and 26 local recurrences were observed. The optimal values for c, TCD50, and k were 10 Gy/cm, 0 Gy, and 31 Gy, respectively. Thus, size-adjusted BED (sBED) may be defined as BED minus 10 times the tumor diameter (in centimeters). Our TCP model indicates that sBED values of 44 Gy, 69 Gy, and 93 Gy provide 80%, 90%, and 95% chances of tumor control at 2 years, respectively. When patients were grouped by sBED, the model accurately characterized the relationship between sBED and actuarial 2-year local control (r=0.847, P=.008). Conclusion: We have developed a TCP model that predicts 2-year local control rate after hypofractionated SBRT for early-stage NSCLC as a function of biologically effective dose and tumor diameter. Further testing of this model with additional datasets is warranted.

  12. A randomized phase III study of accelerated hyperfractionation versus standard in patients with unresected brain metastases: a report of the radiation therapy oncology group (RTOG) 9104

    International Nuclear Information System (INIS)

    Murray, Kevin J.; Scott, Charles; Greenberg, Harvey M.; Emami, Bahman; Seider, Michael; Vora, Nayana L.; Olson, Craig; Whitton, Anthony; Movsas, Benjamin; Curran, Walter

    1997-01-01

    Purpose: To compare 1-year survival and acute toxicity rates between an accelerated hyperfractionated (AH) radiotherapy (1.6 Gy b.i.d.) to a total dose of 54.4 Gy vs. an accelerated fractionation (AF) of 30 Gy in 10 daily fractions in patients with unresected brain metastasis. Methods and Materials: The Radiation Therapy Oncology Group (RTOG) accrued 445 patients to a Phase III comparison of accelerated hyperfractionation vs. standard fractionation from 1991 through 1995. All patients had histologic proof of malignancy at the primary site. Brain metastasis were measurable by CT or MRI scan and all patients had a Karnofsky performance score (KPS) of at least 70 and a neurologic function classification of 1 or 2. For AH, 32 Gy in 20 fractions over 10 treatment days (1.6 Gy twice daily) was delivered to the whole brain. A boost of 22.4 Gy in 14 fractions was delivered to each lesion with a 2-cm margin. Results: The average age in both groups was 60 years; nearly two-thirds of all patients had lung primaries. Of the 429 eligible and analyzable patients, the median survival time was 4.5 months in both arms. The 1-year survival rate was 19% in the AF arm vs. 16% in the AH arm. No difference in median or 1-year survival was observed among patients with solitary metastasis between treatment arms. Recursive partitioning analysis (RPA) classes have previously been identified and patients with a KPS of 70 or more, a controlled primary tumor, less than 65 years of age, and brain metastases only (RPA class I), had a 1-year survival of 35% in the AF arm vs. 25% in the AH arm (p = 0.95). In a multivariate model, only age, KPS, extent of metastatic disease (intracranial metastases only vs. intra- and extracranial metastases), and status of primary (controlled vs. uncontrolled) were statistically significant (at p < 0.05). Treatment assignment was not statistically significant. Overall Grade III or IV toxicity was equivalent in both arms, and one fatal toxicity at 44 days secondary

  13. Modeling Local Control After Hypofractionated Stereotactic Body Radiation Therapy for Stage I Non-Small Cell Lung Cancer: A Report From the Elekta Collaborative Lung Research Group

    International Nuclear Information System (INIS)

    Ohri, Nitin; Werner-Wasik, Maria; Grills, Inga S.; Belderbos, José; Hope, Andrew; Yan Di; Kestin, Larry L.; Guckenberger, Matthias; Sonke, Jan-Jakob; Bissonnette, Jean-Pierre; Xiao, Ying

    2012-01-01

    Purpose: Hypofractionated stereotactic body radiation therapy (SBRT) has emerged as an effective treatment option for early-stage non-small cell lung cancer (NSCLC). Using data collected by the Elekta Lung Research Group, we generated a tumor control probability (TCP) model that predicts 2-year local control after SBRT as a function of biologically effective dose (BED) and tumor size. Methods and Materials: We formulated our TCP model as follows: TCP = e [BED10−c∗L−TCD50]/k ÷ (1 + e [BED10−c∗L−TCD50]/k ), where BED10 is the biologically effective SBRT dose, c is a constant, L is the maximal tumor diameter, and TCD50 and k are parameters that define the shape of the TCP curve. Least-squares optimization with a bootstrap resampling approach was used to identify the values of c, TCD50, and k that provided the best fit with observed actuarial 2-year local control rates. Results: Data from 504 NSCLC tumors treated with a variety of SBRT schedules were available. The mean follow-up time was 18.4 months, and 26 local recurrences were observed. The optimal values for c, TCD50, and k were 10 Gy/cm, 0 Gy, and 31 Gy, respectively. Thus, size-adjusted BED (sBED) may be defined as BED minus 10 times the tumor diameter (in centimeters). Our TCP model indicates that sBED values of 44 Gy, 69 Gy, and 93 Gy provide 80%, 90%, and 95% chances of tumor control at 2 years, respectively. When patients were grouped by sBED, the model accurately characterized the relationship between sBED and actuarial 2-year local control (r=0.847, P=.008). Conclusion: We have developed a TCP model that predicts 2-year local control rate after hypofractionated SBRT for early-stage NSCLC as a function of biologically effective dose and tumor diameter. Further testing of this model with additional datasets is warranted.

  14. Anomalous resonance-radiation energy-transfer rate in a scattering dispersive medium

    International Nuclear Information System (INIS)

    Shekhtman, V.L.

    1992-01-01

    This paper describes a generalization of the concept of group velocity as an energy-transfer rate in a dispersive medium with complex refractive index when the polaritons, which are energy carriers, undergo scattering, in contrast to the classical concept of the group velocity of free polaritons (i.e., without scattering in the medium). The concept of delay time from quantum multichannel-scattering, theory is used as the fundamental concept. Based on Maxwell's equations and the new mathematical Φ-function method, a consistent conceptual definition of group velocity in terms of the ratio of the coherent-energy flux density to the coherent-energy density is obtained for the first time, and a critical analysis of the earlier (Brillouin) understanding of energy-transfer rate is given in the light of radiation-trapping theory and the quantum theory of resonance scattering. The role of generalized group velocity is examined for the interpretation of the phenomenon of multiple resonance scattering, or radiation diffusion. The question of causality for the given problem is touched upon; a new relationship is obtained, called the microcausality condition, which limits the anomalous values of group velocity by way of the indeterminacy principle and the relativistic causality principle for macroscopic time intervals directly measurable in experiment, whereby attention is focused on the connection of the given microcausality condition and the well-known Wigner inequality for the time delay of spherical waves. 22 refs

  15. Velocity distribution in snow avalanches

    Science.gov (United States)

    Nishimura, K.; Ito, Y.

    1997-12-01

    In order to investigate the detailed structure of snow avalanches, we have made snow flow experiments at the Miyanomori ski jump in Sapporo and systematic observations in the Shiai-dani, Kurobe Canyon. In the winter of 1995-1996, a new device to measure static pressures was used to estimate velocities in the snow cloud that develops above the flowing layer of avalanches. Measurements during a large avalanche in the Shiai-dani which damaged and destroyed some instruments indicate velocities increased rapidly to more than 50 m/s soon after the front. Velocities decreased gradually in the following 10 s. Velocities of the lower flowing layer were also calculated by differencing measurement of impact pressure. Both recordings in the snow cloud and in the flowing layer changed with a similar trend and suggest a close interaction between the two layers. In addition, the velocity showed a periodic change. Power spectrum analysis of the impact pressure and the static pressure depression showed a strong peak at a frequency between 4 and 6 Hz, which might imply the existence of either ordered structure or a series of surges in the flow.

  16. A New Method for Estimation of Velocity Vectors

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Munk, Peter

    1998-01-01

    The paper describes a new method for determining the velocity vector of a remotely sensed object using either sound or electromagnetic radiation. The movement of the object is determined from a field with spatial oscillations in both the axial direction of the transducer and in one or two...... directions transverse to the axial direction. By using a number of pulse emissions, the inter-pulse movement can be estimated and the velocity found from the estimated movement and the time between pulses. The method is based on the principle of using transverse spatial modulation for making the received...

  17. Velocity Estimate Following Air Data System Failure

    National Research Council Canada - National Science Library

    McLaren, Scott A

    2008-01-01

    .... A velocity estimator (VEST) algorithm was developed to combine the inertial and wind velocities to provide an estimate of the aircraft's current true velocity to be used for command path gain scheduling and for display in the cockpit...

  18. The influence of tested body size upon longitudinal ultrasonic pulse velocity

    International Nuclear Information System (INIS)

    Suarez Antola, R.

    2001-01-01

    Low ultrasonic frequencies are used in nondestructive testing of heterogeneous materials,such as concrete,rocks and timber.When frequencies are low enough,size and shape of tested bodies may influence measured longitudinal pulse velocities(geometric dispersion).A simplified mathematical model is developed from known experimental and theoretical results obtained for elastic wave propagation in rods of uniform circular cross section.Wave propagation is described by a spatial averaged dilatational field in an approach which is named quasi fluid.A formula is obtained which relates group velocity with an effective lateral size of the body,with transducers a frequency,with a non-dimensional parameter and with asymptotic P-wave velocity.In principle it can be applied to bars of any uniform cross section.The limitations of this formula are discussed in relation to path length,threshold of detection,patterns of radiation and reception and other variables.A more general formula is proposed.Practical application of this formula is briefly exemplified using some experimental data obtained by the author.The problem of longitudinal pulse propagation in reinforcing steel bars embedded in concrete is briefly considered

  19. Doppler velocity measurements from large and small arteries of mice

    Science.gov (United States)

    Reddy, Anilkumar K.; Madala, Sridhar; Entman, Mark L.; Michael, Lloyd H.; Taffet, George E.

    2011-01-01

    With the growth of genetic engineering, mice have become increasingly common as models of human diseases, and this has stimulated the development of techniques to assess the murine cardiovascular system. Our group has developed nonimaging and dedicated Doppler techniques for measuring blood velocity in the large and small peripheral arteries of anesthetized mice. We translated technology originally designed for human vessels for use in smaller mouse vessels at higher heart rates by using higher ultrasonic frequencies, smaller transducers, and higher-speed signal processing. With these methods one can measure cardiac filling and ejection velocities, velocity pulse arrival times for determining pulse wave velocity, peripheral blood velocity and vessel wall motion waveforms, jet velocities for the calculation of the pressure drop across stenoses, and left main coronary velocity for the estimation of coronary flow reserve. These noninvasive methods are convenient and easy to apply, but care must be taken in interpreting measurements due to Doppler sample volume size and angle of incidence. Doppler methods have been used to characterize and evaluate numerous cardiovascular phenotypes in mice and have been particularly useful in evaluating the cardiac and vascular remodeling that occur following transverse aortic constriction. Although duplex ultrasonic echo-Doppler instruments are being applied to mice, dedicated Doppler systems are more suitable for some applications. The magnitudes and waveforms of blood velocities from both cardiac and peripheral sites are similar in mice and humans, such that much of what is learned using Doppler technology in mice may be translated back to humans. PMID:21572013

  20. Cap Bubble Drift Velocity in a Confined Test Section

    International Nuclear Information System (INIS)

    Xiaodong Sun; Seungjin Kim; Mamoru Ishii; Lincoln, Frank W.; Beus, Stephen G.

    2002-01-01

    In the two-group interfacial area transport equation, bubbles are categorized into two groups, i.e., spherical/distorted bubbles as group 1 and cap/slug/churn-turbulent bubbles as group 2. The bubble rise velocities for both groups of bubbles may be estimated by the drift flux model by applying different distribution parameters and drift velocities for both groups. However, the drift velocity for group 2 bubbles is not always applicable (when the wall effect becomes important) as in the current test loop of interest where the flow channel is confined by two parallel flat walls, with a dimension of 200-mm in width and 10-mm in gap. The previous experiments indicated that no stable slug flow existed in this test section, which was designed to permit visualization of the flow patterns and bubble characteristics without the distortion associated with curved surfaces. In fact, distorted cap bubbly and churn-turbulent flow was observed. Therefore, it is essential to developed a correlation for cap bubble drift velocity in this confined flow channel. Since the rise velocity of a cap bubble depends on its size, a high-speed movie camera is used to capture images of cap bubbles to obtain the bubble size information. Meanwhile, the rise velocity of cap and elongated bubbles (called cap bubbles hereafter) is investigated by examining the captured images frame by frame. As a result, the conventional correlation of drift velocity for slug bubbles is modified and acceptable agreements between the measurements and correlation estimation are achieved

  1. Cosmic string induced peculiar velocities

    International Nuclear Information System (INIS)

    van Dalen, A.; Schramm, D.N.

    1987-02-01

    We calculate analytically the probability distribution for peculiar velocities on scales from 10h -1 to 60h -1 Mpc with cosmic string loops as the dominant source of primordial gravitational perturbations. We consider a range of parameters βGμ appropriate for both hot (HDM) and cold (CDM) dark matter scenarios. An Ω = 1 CDM Universe is assumed with the loops randomly placed on a smooth background. It is shown how the effects can be estimated of loops breaking up and being born with a spectrum of sizes. It is found that to obtain large scale streaming velocities of at least 400 km/s it is necessary that either a large value for βGμ or the effect of loop fissioning and production details be considerable. Specifically, for optimal CDM string parameters Gμ = 10 -6 , β = 9, h = .5, and scales of 60h -1 Mpc, the parent size spectrum must be 36 times larger than the evolved daughter spectrum to achieve peculiar velocities of at least 400 km/s with a probability of 63%. With this scenario the microwave background dipole will be less than 800 km/s with only a 10% probability. The string induced velocity spectrum is relatively flat out to scales of about 2t/sub eq//a/sub eq/ and then drops off rather quickly. The flatness is a signature of string models of galaxy formation. With HDM a larger value of βGμ is necessary for galaxy formation since accretion on small scales starts later. Hence, with HDM, the peculiar velocity spectrum will be larger on large scales and the flat region will extend to larger scales. If large scale peculiar velocities greater than 400 km/s are real then it is concluded that strings plus CDM have difficulties. The advantages of strings plus HDM in this regard will be explored in greater detail in a later paper. 27 refs., 4 figs., 1 tab

  2. Angle independent velocity spectrum determination

    DEFF Research Database (Denmark)

    2014-01-01

    An ultrasound imaging system (100) includes a transducer array (102) that emits an ultrasound beam and produces at least one transverse pulse-echo field that oscillates in a direction transverse to the emitted ultrasound beam and that receive echoes produced in response thereto and a spectral vel...... velocity estimator (110) that determines a velocity spectrum for flowing structure, which flows at an angle of 90 degrees and flows at angles less than 90 degrees with respect to the emitted ultrasound beam, based on the received echoes....

  3. Impact of target volume coverage with Radiation Therapy Oncology Group (RTOG) 98-05 guidelines for transrectal ultrasound guided permanent Iodine-125 prostate implants

    International Nuclear Information System (INIS)

    Horwitz, Eric M.; Mitra, Raj K.; Uzzo, Robert G.; Das, Indra J.; Pinover, Wayne H.; Hanlon, Alexandra L.; McNeeley, Shawn W.; Hanks, Gerald E.

    2003-01-01

    Purpose: Despite the wide use of permanent prostate implants for the treatment of early stage prostate cancer, there is no consensus for optimal pre-implant planning guidelines that results in maximal post-implant target coverage. The purpose of this study was to compare post-implant target volume coverage and dosimetry between patients treated before and after Radiation Therapy Oncology Group (RTOG) 98-05 guidelines were adopted using several dosimetric endpoints. Materials and methods: Ten consecutively treated patients before the adoption of the RTOG 98-05 planning guidelines were compared with ten consecutively treated patients after implementation of the guidelines. Pre-implant planning for patients treated pre-RTOG was based on the clinical target volume (CTV) defined by the pre-implant TRUS definition of the prostate. The CTV was expanded in each dimension according to RTOG 98-05 and defined as the planning target volume. The evaluation target volume was defined as the post-implant computed tomography definition of the prostate based on RTOG 98-05 protocol recommendations. Implant quality indicators included V 100 , V 90 , V 100 , and Coverage Index (CI). Results: The pre-RTOG median V 100 , V 90 , D 90 , and CI values were 82.8, 88.9%, 126.5 Gy, and 17.1, respectively. The median post-RTOG V 100 , V 90 , D 90 , and CI values were 96.0, 97.8%, 169.2 Gy, and 4.0, respectively. These differences were all statistically significant. Conclusions: Implementation of the RTOG 98-05 implant planning guidelines has increased coverage of the prostate by the prescription isodose lines compared with our previous technique, as indicated by post-implant dosimetry indices such as V 100 , V 90 , D 90 . The CI was also improved significantly with the protocol guidelines. Our data confirms the validity of the RTOG 98-05 implant guidelines for pre-implant planning as it relates to enlargement of the CTV to ensure adequate margin between the CTV and the prescription isodose

  4. Oncologists’ Perspectives on Consolidation Radiation Treatment after Chemotherapy for Lymphomas: A Survey Study by the Lymphoma Working Committee of the Turkish Oncology Group (TOG)

    Science.gov (United States)

    Tanriverdi, Ozgur; Barista, Ibrahim; Paydas, Semra; Nayir, Erdinc; Karakas, Yusuf

    2017-11-26

    In this study, we aimed to determine the perspectives of medical and radiation oncologists regarding consolidation radiotherapy in patients with a complete response after chemotherapy for Hodgkin’s and non-Hodgkin’s lymphomas. The survey was designed to identify demographic and occupational features of medical and radiation oncologists and their views on application of consolidation radiotherapy in their clinical practices, as based on a five-point Likert scale (never, rarely, sometimes, often, and always). The study covered 263, out of 935, physicians working in the oncology field as either medical or radiation oncologists; the rate of return on the invitations to participate was 28%. The majority of the participants were male radiation oncologists, with a duration of between 5 and 10 years of work as a university hospital official, and the mean age was 38 ± 14 (years). Although the most commonly followed international guidelines were NCCN, among the physicians, the majority of the respondents suggested that the guidelines were unclear regarding recommendations for consolidative radiotherapy. The administered dose for consolidative radiotherapy in lymphoma patients was indicated as 40 Gy by 49% of all the physicians and the most common cause of hesitancy concerning consolidative radiation treatment was the risk of secondary malignancies as a long-term adverse effect (54%). In conclusion, we suggest that medical oncologists could be most active in the treatment of lymphoma through a continuous training program about lymphomas and current national guidelines. Creative Commons Attribution License

  5. ROTATIONAL VELOCITIES FOR M DWARFS

    International Nuclear Information System (INIS)

    Jenkins, J. S.; Ramsey, L. W.; Jones, H. R. A.; Pavlenko, Y.; Barnes, J. R.; Pinfield, D. J.; Gallardo, J.

    2009-01-01

    We present spectroscopic rotation velocities (v sin i) for 56 M dwarf stars using high-resolution Hobby-Eberly Telescope High Resolution Spectrograph red spectroscopy. In addition, we have also determined photometric effective temperatures, masses, and metallicities ([Fe/H]) for some stars observed here and in the literature where we could acquire accurate parallax measurements and relevant photometry. We have increased the number of known v sin i values for mid M stars by around 80% and can confirm a weakly increasing rotation velocity with decreasing effective temperature. Our sample of v sin is peak at low velocities (∼3 km s -1 ). We find a change in the rotational velocity distribution between early M and late M stars, which is likely due to the changing field topology between partially and fully convective stars. There is also a possible further change in the rotational distribution toward the late M dwarfs where dust begins to play a role in the stellar atmospheres. We also link v sin i to age and show how it can be used to provide mid-M star age limits. When all literature velocities for M dwarfs are added to our sample, there are 198 with v sin i ≤ 10 km s -1 and 124 in the mid-to-late M star regime (M3.0-M9.5) where measuring precision optical radial velocities is difficult. In addition, we also search the spectra for any significant Hα emission or absorption. Forty three percent were found to exhibit such emission and could represent young, active objects with high levels of radial-velocity noise. We acquired two epochs of spectra for the star GJ1253 spread by almost one month and the Hα profile changed from showing no clear signs of emission, to exhibiting a clear emission peak. Four stars in our sample appear to be low-mass binaries (GJ1080, GJ3129, Gl802, and LHS3080), with both GJ3129 and Gl802 exhibiting double Hα emission features. The tables presented here will aid any future M star planet search target selection to extract stars with low v

  6. Importance of the mini-mental status examination in the treatment of patients with brain metastases: a report from the radiation therapy oncology group protocol 91-04

    International Nuclear Information System (INIS)

    Murray, Kevin J.; Scott, Charles; Zachariah, Babu; Michalski, Jeff M.; Demas, William; Vora, Nayana L.; Whitton, Anthony; Movsas, Benjamin

    2000-01-01

    Purpose: Little information is available on the importance of pretreatment Mini-Mental Status Exam (MMSE) on long-term survival and neurologic function following treatment for unresectable brain metastases. This study examines the importance of the MMSE in predicting outcome in a group of patients treated with an accelerated fractionation regimen of 30 Gy in 10 daily fractions in 2 weeks. Materials and Methods: The Radiation Therapy Oncology Group (RTOG) accrued 445 patients to a Phase III comparison of accelerated hyperfractionated (AH) radiotherapy (1.6 Gy b.i.d.) to a total dose of 54.4 Gy vs. an accelerated fractionation (AF) of 30 Gy in 10 daily fractions from 1991 through 1995. All patients had histologic proof of malignancy at the primary site. Brain metastases were measurable by CT or MRI scan and all patients had a Karnofsky performance score (KPS) of at least 70 and a neurologic function classification of 1 or 2. Two hundred twenty-four patients were entered on the accelerated fractionated arm, and 182 were eligible for analysis (7 patients were judged ineligible, no MMSE information in 29, no survival data in 1, no forms submitted in 1). Results: Average age was 60 years; 58% were male and 25% had a single intracranial lesion on their pretherapy evaluation. KPS was 70 in 32%, 80 in 31%, 90 in 29%, and 100 in 14%. The average MMSE was 26.5, which is the lower quartile for normal in the U.S. population. The range of the MMSE scores was 11-30 with 30 being the maximum. A score of less than 23 indicates possible dementia, which occurred in 16% of the patients prior to treatment. The median time from diagnosis to treatment was 5 days (range, 0-158 days). The median survival was 4.2 months with a 95% confidence interval of 3.7-5.1 months. Thirty-seven percent of the patients were alive at 6 months, and 17% were alive at 1 year. The following variables were examined in a Cox proportional-hazards model to determine their prognostic value for overall survival

  7. High-velocity winds from a dwarf nova during outburst

    Science.gov (United States)

    Cordova, F. A.; Mason, K. O.

    1982-01-01

    An ultraviolet spectrum of the dwarf nova TW Vir during an optical outburst shows shortward-shifted absorption features with edge velocities as high as 4800 km/s, about the escape velocity of a white dwarf. A comparison of this spectrum with the UV spectra of other cataclysmic variables suggests that mass loss is evident only for systems with relatively high luminosities (more than about 10 solar luminosities) and low inclination angles with respect to the observer's line of sight. The mass loss rate for cataclysmic variables is of order 10 to the -11th solar mass per yr; this is from 0.01 to 0.001 of the mass accretion rate onto the compact star in the binary. The mass loss may occur by a mechanism similar to that invoked for early-type stars, i.e., radiation absorbed in the lines accelerates the accreting gas to the high velocities observed.

  8. Results of a Quality Assurance Review of External Beam Radiation Therapy in the International Society of Paediatric Oncology (Europe) Neuroblastoma Group's High-risk Neuroblastoma Trial: A SIOPEN Study

    International Nuclear Information System (INIS)

    Gaze, Mark N.; Boterberg, Tom; Dieckmann, Karin; Hörmann, Marcus; Gains, Jennifer E.; Sullivan, Kevin P.; Ladenstein, Ruth

    2013-01-01

    Purpose: Radiation therapy is important for local control in neuroblastoma. This study reviewed the compliance of plans with the radiation therapy guidelines of the International Society of Paediatric Oncology (Europe) Neuroblastoma Group (SIOPEN) High-Risk Trial protocol. Methods and Materials: The SIOPEN trial central electronic database has sections to record diagnostic imaging and radiation therapy planning data. Individual centers may upload data remotely, but not all centers involved in the trial chose to use this system. A quality scoring system was devised based on how well the radiation therapy plan matched the protocol guidelines, to what extent deviations were justified, and whether adverse effects may result. Central review of radiation therapy planning was undertaken retrospectively in 100 patients for whom complete diagnostic and treatment sets were available. Data were reviewed and compared against protocol guidelines by an international team of radiation oncologists and radiologists. For each patient in the sample, the central review team assigned a quality assurance score. Results: It was found that in 48% of patients there was full compliance with protocol requirements. In 29%, there were deviations for justifiable reasons with no likely long-term adverse effects resulting. In 5%, deviations had occurred for justifiable reasons, but that might result in adverse effects. In 1%, there was a deviation with no discernible justification, which would not lead to long-term adverse events. In 17%, unjustified deviations were noted, with a risk of an adverse outcome resulting. Conclusions: Owing to concern over the proportion of patients in whom unjustified deviations were observed, a protocol amendment has been issued. This offers the opportunity for central review of radiation therapy plans before the start of treatment and the treating clinician a chance to modify plans.

  9. Results of a Quality Assurance Review of External Beam Radiation Therapy in the International Society of Paediatric Oncology (Europe) Neuroblastoma Group's High-risk Neuroblastoma Trial: A SIOPEN Study

    Energy Technology Data Exchange (ETDEWEB)

    Gaze, Mark N., E-mail: mark.gaze@uclh.nhs.uk [Department of Oncology, University College London Hospitals NHS Foundation Trust, London (United Kingdom); Boterberg, Tom [Department of Radiation Oncology, Ghent University Hospital, Ghent (Belgium); Dieckmann, Karin; Hoermann, Marcus [General Hospital Vienna, Medical University Vienna (Austria); Gains, Jennifer E.; Sullivan, Kevin P. [Department of Oncology, University College London Hospitals NHS Foundation Trust, London (United Kingdom); Ladenstein, Ruth [Children' s Cancer Research Institute, St. Anna Children' s Hospital, Vienna (Austria)

    2013-01-01

    Purpose: Radiation therapy is important for local control in neuroblastoma. This study reviewed the compliance of plans with the radiation therapy guidelines of the International Society of Paediatric Oncology (Europe) Neuroblastoma Group (SIOPEN) High-Risk Trial protocol. Methods and Materials: The SIOPEN trial central electronic database has sections to record diagnostic imaging and radiation therapy planning data. Individual centers may upload data remotely, but not all centers involved in the trial chose to use this system. A quality scoring system was devised based on how well the radiation therapy plan matched the protocol guidelines, to what extent deviations were justified, and whether adverse effects may result. Central review of radiation therapy planning was undertaken retrospectively in 100 patients for whom complete diagnostic and treatment sets were available. Data were reviewed and compared against protocol guidelines by an international team of radiation oncologists and radiologists. For each patient in the sample, the central review team assigned a quality assurance score. Results: It was found that in 48% of patients there was full compliance with protocol requirements. In 29%, there were deviations for justifiable reasons with no likely long-term adverse effects resulting. In 5%, deviations had occurred for justifiable reasons, but that might result in adverse effects. In 1%, there was a deviation with no discernible justification, which would not lead to long-term adverse events. In 17%, unjustified deviations were noted, with a risk of an adverse outcome resulting. Conclusions: Owing to concern over the proportion of patients in whom unjustified deviations were observed, a protocol amendment has been issued. This offers the opportunity for central review of radiation therapy plans before the start of treatment and the treating clinician a chance to modify plans.

  10. Dummy Run of Qu