Intercomparison of three microwave/infrared high resolution line-by-line radiative transfer codes

Science.gov (United States)

Schreier, Franz; Milz, Mathias; Buehler, Stefan A.; von Clarmann, Thomas

2018-05-01

An intercomparison of three line-by-line (lbl) codes developed independently for atmospheric radiative transfer and remote sensing - ARTS, GARLIC, and KOPRA - has been performed for a thermal infrared nadir sounding application assuming a HIRS-like (High resolution Infrared Radiation Sounder) setup. Radiances for the 19 HIRS infrared channels and a set of 42 atmospheric profiles from the "Garand dataset" have been computed. The mutual differences of the equivalent brightness temperatures are presented and possible causes of disagreement are discussed. In particular, the impact of path integration schemes and atmospheric layer discretization is assessed. When the continuum absorption contribution is ignored because of the different implementations, residuals are generally in the sub-Kelvin range and smaller than 0.1 K for some window channels (and all atmospheric models and lbl codes). None of the three codes turned out to be perfect for all channels and atmospheres. Remaining discrepancies are attributed to different lbl optimization techniques. Lbl codes seem to have reached a maturity in the implementation of radiative transfer that the choice of the underlying physical models (line shape models, continua etc) becomes increasingly relevant.

Design and development of radiation absorber for sighting beam line

International Nuclear Information System (INIS)

Sridhar, R.; Shukla, S.K.

2005-01-01

During the commissioning of Indus-2 , it is necessary to view the synchrotron radiation that will be emanating from the dipole exit ports. The 10 0 beam line from dipole 11 was earmarked for sighting beam line. The synchrotron radiation power density would be around 340 watts on the photon absorber inside the radiation absorber module, at the specified beam power of Indus-2. The beam striking on this photon absorber produces x-rays and Bremsstrahlung radiation. These are to be stopped and absorbed by radiation absorber. The photon absorber and the radiation absorber are integrated in a single vacuum chamber and actuated by a pneumatic cylinder connected using a bellow. Radiation absorber was needed to isolate the diagnostic components and to protect them from radiation a well as heat when they were not in use. The paper describes the design, calculation and development of the dynamic photon cum radiation absorber. The ultimate vacuum performance is also described. (author)

Investigation of Magnetospheric Line Radiation above China

Science.gov (United States)

Sheng, X.; Wu, J.; Pu, X.

2017-12-01

Magnetospheric Line Radiation (MLR) is a kind of VLF emission that is considered by some researchers to be related with the power system on ground, and in frequency-time spectrograms of electromagnetic field, it has a line structure with large frequency bandwidth. These emission waves propagate through the magnetosphere and strongly interact with energetic electrons trapped in the earth's magnetic field. Such a wave-particle interaction amplifies the radiation and scatters energetic electrons, which may trigger new radiations. We detected 328 MLR events by analyzing the electric field data observed by DEMETER satellite in the space above China from the year of 2008 to 2010. Their characteristics and possible cause have been investigated systematically. There were more MLR events in daytime than in nighttime and more in winter than in summer. Such diurnal and seasonal differences were closely associated with whistlers and ionosphere conditions. Comparing Kp indices at the occurring time of MLR events and nationwide Kp indices through the analyzed years, we found these MLR events were not significantly dependent on geomagnetic activity. Most of events were distributed in the low latitude, while their peak intensities in frequency-time spectrograms seemed to be independent of latitude. The frequency intervals of MLR events were between 50 to 95Hz, and the frequency drifts were mostly in 0 0.4Hz/s. The above characteristics of MLR events were similar to those of Power Line Harmonic Radiation (PLHR) events observed in the space above China, therefore we inferred that these two emissions have close relation.

Radiation sensitivity of Merkell cell carcinoma cell lines

International Nuclear Information System (INIS)

Leonard, J. Helen; Ramsay, Jonathan R.; Kearsley, John H.; Birrell, Geoff W.

1995-01-01

Purpose: Merkel cell carcinoma (MCC), being a small cell carcinoma, would be expected to be sensitive to radiation. Clinical analysis of patients at our center, especially those with macroscopic disease, would suggest the response is quite variable. We have recently established a number of MCC cell lines from patients prior to radiotherapy, and for the first time are in a position to determine their sensitivity under controlled conditions. Methods and Materials: Some of the MCC lines grew as suspension cultures and could not be single cell cloned; therefore, it was not possible to use clonogenic survival for all cell lines. A tetrazolium based (MTT) assay was used for these lines, to estimate cell growth after γ irradiation. Control experiments were conducted on lymphoblastoid cell lines (LCL) and the adherent MCC line, MCC13, to demonstrate that the two assays were comparable under the conditions used. Results: We have examined cell lines from MCC, small cell lung cancer (SCLC), malignant melanomas, Epstein Barr virus (EBV) transformed lymphocytes (LCL), and skin fibroblasts for their sensitivity to γ irradiation using both clonogenic cell survival and MTT assays. The results show that the tumor cell lines have a range of sensitivities, with melanoma being more resistant (surviving fraction at 2 Gy (SF2) 0.57 and 0.56) than the small cell carcinoma lines, MCC (SF2 range 0.21-0.45, mean SF2 0.30, n = 8) and SCLC (SF2 0.31). Fibroblasts were the most sensitive (SF2 0.13-0.20, mean 0.16, n = 5). The MTT assay, when compared to clonogenic assay for the MCC13 adherent line and the LCL, gave comparable results under the conditions used. Conclusion: Both assays gave a range of SF2 values for the MCC cell lines, suggesting that these cancers would give a heterogeneous response in vivo. The results with the two derivative clones of MCC14 (SF2 for MCC14/1 0.38, MCC14/2 0.45) would further suggest that some of them may develop resistance during clonogenic evolution

Radiation response of mouse lymphoid and myeloid cell lines. Pt. 3

International Nuclear Information System (INIS)

Radford, I.R.; Murphy, T.K.

1994-01-01

The authors have examined the timing of γ-irradiation-induced death in relation to cell cycle progression using a panel of mouse lymphoid or myeloid cell lines. Death was found to occur immediately after irradiation ('rapid interphase' death), or after arrest in G 2 phase ('delayed interphase' death), or following one or more mitoses ('mitotic/delayed mitotic' death). In part II of this series of papers the authors demonstrated the occurrence of radiation-induced apoptosis in all these cell lines. Several of the cell lines showed different timing of death dependent upon the radiation dose used. These differences in the timing of radiation-induced death are shown to be useful indicators of the relative radiosensitivity of haematopoietic cell lines. (author)

The influence of continuum radiation fields on hydrogen radio recombination lines

Science.gov (United States)

Prozesky, Andri; Smits, Derck P.

2018-05-01

Calculations of hydrogen departure coefficients using a model with the angular momentum quantum levels resolved that includes the effects of external radiation fields are presented. The stimulating processes are important at radio frequencies and can influence level populations. New numerical techniques with a solid mathematical basis have been incorporated into the model to ensure convergence of the solution. Our results differ from previous results by up to 20 per cent. A direct solver with a similar accuracy but more efficient than the iterative method is used to evaluate the influence of continuum radiation on the hydrogen population structure. The effects on departure coefficients of continuum radiation from dust, the cosmic microwave background, the stellar ionising radiation, and free-free radiation are quantified. Tables of emission and absorption coefficients for interpreting observed radio recombination lines are provided.

Design of x-ray diagnostic beam line for a synchrotron radiation source and measurement results

Energy Technology Data Exchange (ETDEWEB)

Garg, Akash Deep, E-mail: akash-deep@rrcat.gov.in; Karnewar, A.K.; Ojha, A.; Shrivastava, B.B.; Holikatti, A.C.; Puntambekar, T.A.; Navathe, C.P.

2014-08-01

Indus-2 is a 2.5 GeV synchrotron radiation source (SRS) operational at the Raja Ramanna Centre for Advanced Technology (RRCAT) in India. We have designed, developed and commissioned x-ray diagnostic beam line (X-DBL) at the Indus-2. It is based on pinhole array imaging (8–18 keV). We have derived new equations for online measurements of source position and emission angle with pinhole array optics. Measured values are compared with the measurements at an independent x-ray beam position monitor (staggered pair blade monitor) installed in the X-DBL. The measured values are close to the theoretical expected values within ±12 µm (or ±1.5 μrad) for sufficiently wide range of the beam movements. So, beside the beam size and the beam emittance, online information for the vertical position and angle is also used in the orbit steering. In this paper, the various design considerations of the X-DBL and online measurement results are presented.

Radiation of different human melanoma cell lines increased expression of RHOB. Level of this tumor suppressor gene in different cell lines

International Nuclear Information System (INIS)

Notcovich, C.; Molinari, B.; Duran, H.; Delgado González, D.; Sánchez Crespo, R.

2013-01-01

Previous results of our group show that a correlation exists between intrinsic radiosensitivity of human melanoma cells and cell death by apoptosis. RhoB is a small GTPase that regulates cytoskeletal organization. Besides, is related to the process of apoptosis in cells exposed to DNA damage as radiation. Also, RhoB levels decrease in a wide variety of tumors with the tumor stage, being considered a tumor suppressor gene due to its antiproliferative and proapoptotic effect. The aim of this study was to analyze the expression of RhoB in different human melanoma cell lines in relation to melanocytes, and evaluate the effect of gamma radiation on the expression of RhoB. We used the A375, SB2 and Meljcell lines, and the derived from melanocytes Pig1. It was found for all three tumor lines RhoB expression levels significantly lower than those of Pig1 (p <0.05), as assessed by semiquantitative RT-PCR . When tumor cells were irradiated to a dose of 2Gyinduction was observed at 3 hours RhoB irradiation. RhoB expression increased in all lines relative to non-irradiated control, showing a greater induction ( p< 0.05) for the more radiosensitive line SB2, consistent with apoptosis in response to radiation. The results allow for the first time in melanoma demonstrate that RhoB, as well as in other tumor types, has a lower expression in tumor cells than their normal counterparts. Moreover, induction in the expression of RhoB in irradiated cells may be associated with the process of radiation-induced apoptosis. The modulation of RhoB could be a new tool to sensitize radioresistant melanoma. (author)

Radiation sensitivity of Merkel cell carcinoma cell lines

Energy Technology Data Exchange (ETDEWEB)

Leonard, J.H.; Ramsay, J.R.; Birrell, G.W. [Queensland Institute of Medical Research (Australia)] [and others

1995-07-30

Merkel cell carcinoma (MCC), being a small cell carcinoma, would be expected to be sensitive to radiation. Clinical analysis of patients at our center, especially those with macroscopic disease, would suggest the response is quite variable. We have recently established a number of MCC cell lines from patients prior to radiotherapy, and for the first time are in a position to determine their sensitivity under controlled conditions. Some of the MCC lines grew as suspension cultures and could not be single cell cloned; therefore, it was not possible to use clonogenic survival for all cell lines. A tetrazolium based (MTT) assay was used for these lines, to estimate cell growth after {gamma} irradiation. Control experiments were conducted on lymphoblastoid cell lines (LCL) and the adherent MCC line, MCC13, to demonstrate that the two assays were comparable under the conditions used. We have examined cell lines from MCC, small cell lung cancer (SCLC), malignant melanomas, Epstein Barr virus (EBV) transformed lymphocytes (LCL), and skin fibroblasts for their sensitivity to {gamma} irradiation using both clonogenic cell survival and MTT assays. The results show that the tumor cell lines have a range of sensitivities, with melanoma being more resistant (surviving fraction at 2 Gy (SF2) 0.57 and 0.56) than the small cell carcinoma lines, MCC (SF2 range 0.21-0.45, mean SF2 0.30, n = 8) and SCLC (SF2 0.31). Fibroblasts were the most sensitive (SF2 0.13-0.20, mean 0.16, n = 5). The MTT assay, when compared to clonogenic assay for the MCC13 adherent line and the LCL, gave comparable results under the conditions used. Both assays gave a range of SF2 values for the MCC cell lines, suggesting that these cancers would give a heterogeneous response in vivo. The results with the two derivative clones of MCC14 (SF2 for MCC14/1 0.38, MCC14/2 0.45) would further suggest that some of them may develop resistance during clonogenic evolution. 25 refs., 3 figs., 1 tab.

Kelussia odoratissima potentiates cytotoxic effects of radiation in HeLa cancer cell line

Directory of Open Access Journals (Sweden)

Azar Hosseini

2017-02-01

Full Text Available Objective: Cervical cancer is the second most common cause of death from cancer in women throughout the world. The aim of this study was to evaluate the cytotoxic activity of Kelussia odoratissima (K. odoratissima extract associated with radiotherapy in cervical cancer cells (HeLa cell line.Materials and Methods: Different concentration of the extract (25-500µg/ml was tested in HeLa cell lines. Cell cytotoxicity of the extract and the effects of the extract on radiation (2Gy/min-induced damages were assessed by MTT assay. Apoptosis was assessed using flow cytometric analysis.Result: K. odoratissima decreased cell viability in HeLa cell line in a concentration and time-dependent manner. When compared to the control,K. odoratissima induced a sub-G1 peak in the flow cytometry histogram of treated cells, indicating that apoptotic cell death is involved in K. odoratissima-induced toxicity. It was also shown that K. odoratissima sensitizes cells to radiation-induced toxicity.Conclusion: Our result showed the extract increased the radiation effect. This observation may be related to the presence of active compounds such as phthalides and ferulic acid.

Calculation of the line shapes of radiators immersed in plasma

International Nuclear Information System (INIS)

Hayrapetian, A.S.

1987-01-01

This work reports the results of theoretical calculations of line shapes of radiators immersed in plasma. The fluctuating electric field of the plasma perturbs the atomic structure of the immersed ions or atoms. The perturbed line shape is an important diagnostic tool for the temperature and density measurements of plasma. The line-shape calculation here is done by first deriving the line-shape expression, then it is shown that the problem is equivalent to calculating the temperature Green's function of the bound electron. The total Hamiltonian of the system includes the atomic, plasma, and atom-plasma parts. The temperature Green's function is calculated perturbatively by expanding in orders of atom-plasma interaction. By solving a Dyson equation, the dressed Green's functions of the bound electrons are obtained. At this point, the line shape is calculated by an analytic continuation from the complex frequency plane to real line. To derive the atomic electron Green's function, the momentum integral in the self-energy is approximated by a Riemann sum. With this approximation, the algebraic form of the line shape is obtained for an undetermined number of terms in the Riemann sum. Numerical calculation of line shape is done by using this result

Radiation Response in Two HPV-Infected Head-and-Neck Cancer Cell Lines in Comparison to a Non-HPV-Infected Cell Line and Relationship to Signaling Through AKT

International Nuclear Information System (INIS)

Gupta, Anjali K.; Lee, John H.; Wilke, Werner W.; Quon, Harry; Smith, Gareth; Maity, Amit; Buatti, John M.; Spitz, Douglas R.

2009-01-01

Purpose: Human papilloma virus (HPV)-associated cancers of the head and neck (H and N) are increasing in frequency and are often treated with radiation. There are conflicting data in the literature regarding the radiation response in the presence of HPV infection, with some data suggesting they may be more sensitive to radiation. There are few studies looking at in vitro effects of HPV and further sensitization by inhibitors of specific signaling pathways. We are in the process of starting a clinical trial in H and N cancer patients using nelfinavir (NFV) (which inhibits Akt) and it would be important to know the effect of HPV on radiation response ± NFV. Methods and Materials: Two naturally infected HPV-16 cell lines (UPCI-SCC90 and UMSCC47) and the HPV-negative SQ20B H and N squamous carcinoma cells were used. Western blots with or without 10 uM NFV were done to evaluate signaling from the PI3K-Akt pathway. Clonogenic assays were done in the three cell lines with or without NFV. Results: Both UPCI-SCC90 and UMSCC47 cells were sensitive to radiation as compared with SQ20B and the degree corresponded to Akt activation. The SQ20B cell line has an activating mutation in EGFR resulting in phosphorylation (P) of Akt; UMSCC47 has decreased P-phosphatase and TENsin (PTEN), resulting in increased P-Akt; UPCI-SCC90 had overexpression of P-PTEN and decreased P-Akt. NFV resulted in downregulation of Akt in all three cell lines, resulting in sensitization to radiation. Conclusions: HPV-infected H and N cancers are sensitive to radiation. The degree of sensitivity correlates to Akt activation and they can be further sensitized by NFV.

Importance of representing optical depth variability for estimates of global line-shaped contrail radiative forcing.

Science.gov (United States)

Kärcher, Bernd; Burkhardt, Ulrike; Ponater, Michael; Frömming, Christine

2010-11-09

Estimates of the global radiative forcing by line-shaped contrails differ mainly due to the large uncertainty in contrail optical depth. Most contrails are optically thin so that their radiative forcing is roughly proportional to their optical depth and increases with contrail coverage. In recent assessments, the best estimate of mean contrail radiative forcing was significantly reduced, because global climate model simulations pointed at lower optical depth values than earlier studies. We revise these estimates by comparing the probability distribution of contrail optical depth diagnosed with a climate model with the distribution derived from a microphysical, cloud-scale model constrained by satellite observations over the United States. By assuming that the optical depth distribution from the cloud model is more realistic than that from the climate model, and by taking the difference between the observed and simulated optical depth over the United States as globally representative, we quantify uncertainties in the climate model's diagnostic contrail parameterization. Revising the climate model results accordingly increases the global mean radiative forcing estimate for line-shaped contrails by a factor of 3.3, from 3.5 mW/m(2) to 11.6 mW/m(2) for the year 1992. Furthermore, the satellite observations and the cloud model point at higher global mean optical depth of detectable contrails than often assumed in radiative transfer (off-line) studies. Therefore, we correct estimates of contrail radiative forcing from off-line studies as well. We suggest that the global net radiative forcing of line-shaped persistent contrails is in the range 8-20 mW/m(2) for the air traffic in the year 2000.

Delay-Line Three-Dimensional Position Sensitive Radiation Detection

Science.gov (United States)

Jeong, Manhee

High-resistivity silicon(Si) in large volumes and with good charge carrier transport properties has been produced and achieved success as a radiation detector material over the past few years due to its relatively low cost as well as the availability of well-established processing technologies. One application of that technology is in the fabrication of various position-sensing topologies from which the incident radiation's direction can be determined. We have succeeded in developing the modeling tools for investigating different position-sensing schemes and used those tools to examine both amplitude-based and time-based methods, an assessment that indicates that fine position-sensing can be achieved with simpler readout designs than are conventionally deployed. This realization can make ubiquitous and inexpensive deployment of special nuclear materials (SNM) detecting technology becomes more feasible because if one can deploy position-sensitive semiconductor detectors with only one or two contacts per side. For this purpose, we have described the delay-line radiation detector and its optimized fabrication. The semiconductor physics were simulated, the results from which guided the fabrication of the guard ring structure and the detector electrode, both of which included metal-field-plates. The measured improvement in the leakage current was confirmed with the fabricated devices, and the structures successfully suppressed soft-breakdown. We also demonstrated that fabricating an asymmetric strip-line structure successfully minimizing the pulse shaping and increases the distance through which one can propagate the information of the deposited charge distribution. With fabricated delay-line detectors we can acquire alpha spectra (Am-241) and gamma spectra (Ba-133, Co-57 and Cd-109). The delay-line detectors can therefore be used to extract the charge information from both ion and gamma-ray interactions. Furthermore, standard charge-sensitive circuits yield high SNR

Structure, shape, and evolution of radiatively accelerated QSO emission-line clouds

International Nuclear Information System (INIS)

Blumenthal, G.R.; Mathews, W.G.

1979-01-01

The possibility that the broad emission-line regions of QSOs and active galactic nuclei are formed by a multitude of small clouds which are radiatively accelerated is discussed. Although this model is by no means certain at present, it has four virtues: (1) Observed emission-line widths can be produced with observationally allowed electron densities, UV luminosities, and ionization levels. (2) The acceleration force is coherent in each cloud are found. (3) Reasonable line profiles can result for all emission lines. (4) Photoionization of hydrogen accounts for both heating and acceleration of the emission-line gas. A self-consistent model is developed for the structure, shape, and evolution of radiatively accelerated clouds. The shape varies with cloud mass, and two distinct types of clouds. Fully ionized clouds of very low mass approach a nearly spherical shape. However, all clouds having masses greater than some critical mass adopt a ''pancake'' shape. The condition for constant cloud mass in the cloud frame is shown to be equivalent to the equation of motion of a cloud in the rest frame of the QSO. The emission-line profiles can be sensitive to radial variations in the properties of the intercloud medium, and those properties that correspond to observed profiles are discussed. Finally, the covering factor of a system of pancake clouds is estimated along with the total number of clouds required--approximately 10 14 clouds in each QSO

An Algorithm to Compress Line-transition Data for Radiative-transfer Calculations

Science.gov (United States)

Cubillos, Patricio E.

2017-11-01

Molecular line-transition lists are an essential ingredient for radiative-transfer calculations. With recent databases now surpassing the billion-line mark, handling them has become computationally prohibitive, due to both the required processing power and memory. Here I present a temperature-dependent algorithm to separate strong from weak line transitions, reformatting the large majority of the weaker lines into a cross-section data file, and retaining the detailed line-by-line information of the fewer strong lines. For any given molecule over the 0.3-30 μm range, this algorithm reduces the number of lines to a few million, enabling faster radiative-transfer computations without a significant loss of information. The final compression rate depends on how densely populated the spectrum is. I validate this algorithm by comparing Exomol’s HCN extinction-coefficient spectra between the complete (65 million line transitions) and compressed (7.7 million) line lists. Over the 0.6-33 μm range, the average difference between extinction-coefficient values is less than 1%. A Python/C implementation of this algorithm is open-source and available at https://github.com/pcubillos/repack. So far, this code handles the Exomol and HITRAN line-transition format.

GARLIC — A general purpose atmospheric radiative transfer line-by-line infrared-microwave code: Implementation and evaluation

International Nuclear Information System (INIS)

Schreier, Franz; Gimeno García, Sebastián; Hedelt, Pascal; Hess, Michael; Mendrok, Jana; Vasquez, Mayte; Xu, Jian

2014-01-01

A suite of programs for high resolution infrared-microwave atmospheric radiative transfer modeling has been developed with emphasis on efficient and reliable numerical algorithms and a modular approach appropriate for simulation and/or retrieval in a variety of applications. The Generic Atmospheric Radiation Line-by-line Infrared Code — GARLIC — is suitable for arbitrary observation geometry, instrumental field-of-view, and line shape. The core of GARLIC's subroutines constitutes the basis of forward models used to implement inversion codes to retrieve atmospheric state parameters from limb and nadir sounding instruments. This paper briefly introduces the physical and mathematical basics of GARLIC and its descendants and continues with an in-depth presentation of various implementation aspects: An optimized Voigt function algorithm combined with a two-grid approach is used to accelerate the line-by-line modeling of molecular cross sections; various quadrature methods are implemented to evaluate the Schwarzschild and Beer integrals; and Jacobians, i.e. derivatives with respect to the unknowns of the atmospheric inverse problem, are implemented by means of automatic differentiation. For an assessment of GARLIC's performance, a comparison of the quadrature methods for solution of the path integral is provided. Verification and validation are demonstrated using intercomparisons with other line-by-line codes and comparisons of synthetic spectra with spectra observed on Earth and from Venus. - Highlights: • High resolution infrared-microwave radiative transfer model. • Discussion of algorithmic and computational aspects. • Jacobians by automatic/algorithmic differentiation. • Performance evaluation by intercomparisons, verification, validation

Radiative transfer in molecular lines

Science.gov (United States)

Asensio Ramos, A.; Trujillo Bueno, J.; Cernicharo, J.

2001-07-01

The highly convergent iterative methods developed by Trujillo Bueno and Fabiani Bendicho (1995) for radiative transfer (RT) applications are generalized to spherical symmetry with velocity fields. These RT methods are based on Jacobi, Gauss-Seidel (GS), and SOR iteration and they form the basis of a new NLTE multilevel transfer code for atomic and molecular lines. The benchmark tests carried out so far are presented and discussed. The main aim is to develop a number of powerful RT tools for the theoretical interpretation of molecular spectra.

X-ray diffraction using synchrotron radiation on the G.I.L.D.A. beam line at the E.S.R.F

Energy Technology Data Exchange (ETDEWEB)

Balerna, A [INFN, Laboratori Nazionali di Frascati, Rome (Italy); Meneghini, C [INFN, Laboratori Nazionali di Frascati, Rome (Italy); [INFM, Genoa (Italy); Bordoni, S [Rome Univ. ` Tor Vergata` (Italy). Dip. di Fisica; Mobilio, S [Rome Univ. III (Italy). Dip. di Fisica ` E. Amaldi`

1996-09-01

The aim of this lecture is to make a short introduction on Synchrotron radiation, its history and main properties. The main components of a synchrotron radiation beam line will be described. The Italian beam line, General purpose Italian beam line Line for Diffraction and Absorption (G.I.L.D.A.) at the European Synchrotron Radiation Facility (E.S.R.F.) in Grenoble will be used as an example. The G.I.L.D.A. diffractometer will be described in detail reporting also some experimental results.

Application of the inter-line PCR for the analyse of genomic rearrangements in radiation-transformed mammalian cell lines

International Nuclear Information System (INIS)

Leibhard, S.; Smida, J.

1996-01-01

Repetitive DNA sequences of the LINE-family (long interspersed elements) that are widely distributed among the mammalian genome can be activated or altered by the exposure to ionizing radiation [1]. By the integration at new sites in the genome alterations in the expression of genes that are involved in cell transformation and/or carcinogenesis may occur [2, 3]. A new technique -the inter-LINE PCR - has been developed in order to detect and analyse such genomic rearrangements in radiation-transformed cell lines. From the sites of transformation- or tumour-specific changes in the genome it might be possible to develop new tumour markers for diagnostic purpose. (orig.) [de

The Development of On-Line Statistics Program for Radiation Oncology

International Nuclear Information System (INIS)

Kim, Yoon Jong; Lee, Dong Hoon; Ji, Young Hoon; Lee, Dong Han; Jo, Chul Ku; Kim, Mi Sook; Ru, Sung Rul; Hong, Seung Hong

2001-01-01

Purpose : By developing on-line statistics program to record the information of radiation oncology to share the information with internet. It is possible to supply basic reference data for administrative plans to improve radiation oncology. Materials and methods : The information of radiation oncology statistics had been collected by paper forms about 52 hospitals in the past. Now, we can input the data by internet web browsers. The statistics program used windows NT 4.0 operation system, Internet Information Server 4.0 (IIS4.0) as a web server and the Microsoft Access MDB. We used Structured Query Language (SQL), Visual Basic, VBScript and JAVAScript to display the statistics according to years and hospitals. Results : This program shows present conditions about man power, research, therapy machines, technic, brachytherapy, clinic statistics, radiation safety management, institution, quality assurance and radioisotopes in radiation oncology department. The database consists of 38 inputs and 6 outputs windows. Statistical output windows can be increased continuously according to user need. Conclusion : We have developed statistics program to process all of the data in department of radiation oncology for reference information. Users easily could input the data by internet web browsers and share the information

GARLIC - A general purpose atmospheric radiative transfer line-by-line infrared-microwave code: Implementation and evaluation

Science.gov (United States)

Schreier, Franz; Gimeno García, Sebastián; Hedelt, Pascal; Hess, Michael; Mendrok, Jana; Vasquez, Mayte; Xu, Jian

2014-04-01

A suite of programs for high resolution infrared-microwave atmospheric radiative transfer modeling has been developed with emphasis on efficient and reliable numerical algorithms and a modular approach appropriate for simulation and/or retrieval in a variety of applications. The Generic Atmospheric Radiation Line-by-line Infrared Code - GARLIC - is suitable for arbitrary observation geometry, instrumental field-of-view, and line shape. The core of GARLIC's subroutines constitutes the basis of forward models used to implement inversion codes to retrieve atmospheric state parameters from limb and nadir sounding instruments. This paper briefly introduces the physical and mathematical basics of GARLIC and its descendants and continues with an in-depth presentation of various implementation aspects: An optimized Voigt function algorithm combined with a two-grid approach is used to accelerate the line-by-line modeling of molecular cross sections; various quadrature methods are implemented to evaluate the Schwarzschild and Beer integrals; and Jacobians, i.e. derivatives with respect to the unknowns of the atmospheric inverse problem, are implemented by means of automatic differentiation. For an assessment of GARLIC's performance, a comparison of the quadrature methods for solution of the path integral is provided. Verification and validation are demonstrated using intercomparisons with other line-by-line codes and comparisons of synthetic spectra with spectra observed on Earth and from Venus.

Environmental Radiation Surveillance Results from over the Last Decade of Operational Experience at the Regional Radiation Monitoring Stations(RRMS)

Energy Technology Data Exchange (ETDEWEB)

Lee, Hae Young [Daegu Regional Radiation Monitoring Station, Daegu (Korea, Republic of); Yoo, Dong Han [Ulsan Regional Radiation Monitoring Station, Ulsan (Korea, Republic of); Lee, Sang Hoon [Kyungpook National University, Daegu (Korea, Republic of)

2015-10-15

The objectives of the current program are to monitor environmental radiation/radioactivity level in Korea and to provide the base-line data on environmental radiation/radioactivity which will be useful in the case of radiological emergency situations. This program plays an important role in the view of protecting the public health against the potential hazards of radiation and maintaining a clean environment. This paper describes an introduction to the Regional Radiation Monitoring Stations (RRMS), and also presents some results of recent years (2001-2014). The environmental radiation surveillance results of years 2001-2014 have been described. It indicates normal levels of radiation in the past years. These kinds of studies are very important in providing references in understanding the environmental radioactivity level in a particular region.

SEURAT: SPH scheme extended with ultraviolet line radiative transfer

Science.gov (United States)

Abe, Makito; Suzuki, Hiroyuki; Hasegawa, Kenji; Semelin, Benoit; Yajima, Hidenobu; Umemura, Masayuki

2018-05-01

We present a novel Lyman alpha (Ly α) radiative transfer code, SEURAT (SPH scheme Extended with Ultraviolet line RAdiative Transfer), where line scatterings are solved adaptively with the resolution of the smoothed particle hydrodynamics (SPH). The radiative transfer method implemented in SEURAT is based on a Monte Carlo algorithm in which the scattering and absorption by dust are also incorporated. We perform standard test calculations to verify the validity of the code; (i) emergent spectra from a static uniform sphere, (ii) emergent spectra from an expanding uniform sphere, and (iii) escape fraction from a dusty slab. Thereby, we demonstrate that our code solves the {Ly} α radiative transfer with sufficient accuracy. We emphasize that SEURAT can treat the transfer of {Ly} α photons even in highly complex systems that have significantly inhomogeneous density fields. The high adaptivity of SEURAT is desirable to solve the propagation of {Ly} α photons in the interstellar medium of young star-forming galaxies like {Ly} α emitters (LAEs). Thus, SEURAT provides a powerful tool to model the emergent spectra of {Ly} α emission, which can be compared to the observations of LAEs.

Radiation equivalence of genotoxic chemicals - Validation in cultered mammalian cell lines

International Nuclear Information System (INIS)

Murthy, M.S.S.

1982-01-01

Published data on mutations induced by ionizing radiation and 6 monofunctional alkylating agents, namely EMS, MMS, ENNG, MNNG, ENU and MNU, in different cell lines (Chinese hamster ovary, Chinese hamster lung V79, mouse lymphoma L5178 and human cells) were analysed so that radiation-equivalent chemical (REC) values could be calculated. REC values thus obtained for a given alkylating agent with different cell lines fall within a narrow range suggesting its validation in cultured mammalian cell systems including human. (orig.)

Endogenous superoxide dismutase and catalase activities and radiation resistance in mouse cell lines

International Nuclear Information System (INIS)

Davy, C.A.; Tesfay, Z.; Jones, J.; Rosenberg, R.C.; McCarthy, C.; Ostrand-Rosenberg, S.

1988-01-01

The relationship between the endogenous cytoplasmic levels of the enzymes superoxide dismutase and catalase and the inhibition of cell proliferation by γ-radiation has been studied in 11 mouse cell lines. The resistance of these mouse cell lines to radiation was found to vary by over 25-fold. No correlation was found between the cytoplasmic level of CuZn-superoxide dismutase or catalase and the resistance to radiation as measured by extrapolation number (EN), quasi-threshold dose (Dsub(q)), or Dsub(o). None of the cell lines had detectable cytoplasmic Mn-superoxide dismutase. The apparent Ksub(i) of potassium cyanide for mouse CuZn-superoxide dismutase was determined (Ksub(i) = 6.5 μmol dm -3 ). (author)

Solving radiative transfer with line overlaps using Gauss-Seidel algorithms

Science.gov (United States)

Daniel, F.; Cernicharo, J.

2008-09-01

Context: The improvement in observational facilities requires refining the modelling of the geometrical structures of astrophysical objects. Nevertheless, for complex problems such as line overlap in molecules showing hyperfine structure, a detailed analysis still requires a large amount of computing time and thus, misinterpretation cannot be dismissed due to an undersampling of the whole space of parameters. Aims: We extend the discussion of the implementation of the Gauss-Seidel algorithm in spherical geometry and include the case of hyperfine line overlap. Methods: We first review the basics of the short characteristics method that is used to solve the radiative transfer equations. Details are given on the determination of the Lambda operator in spherical geometry. The Gauss-Seidel algorithm is then described and, by analogy to the plan-parallel case, we see how to introduce it in spherical geometry. Doing so requires some approximations in order to keep the algorithm competitive. Finally, line overlap effects are included. Results: The convergence speed of the algorithm is compared to the usual Jacobi iterative schemes. The gain in the number of iterations is typically factors of 2 and 4 for the two implementations made of the Gauss-Seidel algorithm. This is obtained despite the introduction of approximations in the algorithm. A comparison of results obtained with and without line overlaps for N2H^+, HCN, and HNC shows that the J=3-2 line intensities are significantly underestimated in models where line overlap is neglected.

Effects of hyperthermia and ionizing radiation in normal and ataxia telangiectasia human fibroblast lines

International Nuclear Information System (INIS)

Mitchel, R.E.J.; Chan, A.; Smith, B.P.; Child, S.D.; Paterson, M.C.

1984-01-01

The effects of 45 0 C hyperthermia and γ radiation have been studied in three normal human fibroblast lines (GM38, GM730, WI38) and compared to the effects in two lines derived from patients with the hereditary disease ataxia telangiectasia (AR3BI, AT5BI). All lines, both normal and γ-sensitive AT, showed a similar resistance to killing by heat alone, suggesting that the defect responsible for the increased radiation sensitivity in AT lines does not confer increased heat sensitivity. Shouldered survival curves were obtained in each case indicating the ability to accumulate sublethal heat damage. All normal and AT cell lines exhibited increased resistance to the lethal effects of heat in response to a thermal stress, indicating that the defect that causes radiosensitivity in AT cell lines does not prevent the induction of thermotolerance. It was hypothesized that in normal cells, this heat treatment inactivates the process which is already defective in AT lines, and that this process may be required for the proper rejoining of double-strand breaks produced during the repair of other radiation-induced lesions

Reduction of the electromagnetic radiation in high tension lines

International Nuclear Information System (INIS)

Araya Padilla, Eddie A.

2006-01-01

Introduces like the design of the transmission lines determine the profile of the electric and magnetic generated field. This profile is calculated with the use of the equations of Maxwell, and it depends rely on diverse geometries and operative factors of the line, so that an adequate physical distribution of the tower configuration, it could diminish the intensity of radiation generated inside of and in the border of right of way of the line. Pattern like the electric and magnetic generated fields are distributed satisfactorily, by means of the analysis of sensibility of parameters of design. (author) [es

Radiation loss of planar surface plasmon polaritons transmission lines at microwave frequencies.

Science.gov (United States)

Xu, Zhixia; Li, Shunli; Yin, Xiaoxing; Zhao, Hongxin; Liu, Leilei

2017-07-21

Radiation loss of a typical spoof surface plasmon polaritons (SSPPs) transmission line (TL) is investigated in this paper. A 325 mm-long SSPPs TL is designed and fabricated. Simulated results show that radiation loss contributes more to transmission loss than dielectric loss and conductor loss from 2 GHz to 10 GHz. Radiation loss of the SSPPs TL could be divided into two parts, one is caused by the input mode converter, and the other is caused by the corrugated metallic strip. This paper explains mechanisms of radiation loss from different parts, designs a loaded SSPPs TL with a series of resistors to absorb electromagnetic energy on corrugated metallic strip, and then discriminates radiation loss from the input mode converter, proposes the concept of average radiation length (ARL) to evaluate radiation loss from SSPPs of finite length, and concludes that radiation loss is mainly caused by corrugated structure of finite length at low frequency band and by the input mode converter at high frequency band. To suppress radiation loss, a mixed slow wave TL based on the combination of coplanar waveguides (CPWs) and SSPPs is presented. The designed structure, sample fabrication and experimental verification are discussed.

Radiation from a Slot System in the Coaxial Line Shield

Science.gov (United States)

Katrich, V. A.; Lyashchenko, V. A.; Medvedev, N. V.

2012-06-01

The problem of electromagnetic wave excitation, scattering and radiation by the system of transverse slots, cut in the outer conductor of an infinite coaxial line, is solved by the magnetomotive forces method. The radiation and reflection coefficients of the circular and arc slot systems are investigated in dependence on slot sizes and feeder parameters. The processes of radiation into lossy material media are studied. The researches have been carried out with the interconnection between slots of internal and external regions considered.

Heterogeneity in 2-deoxy-D-glucose-induced modifications in energetics and radiation responses of human tumor cell lines

International Nuclear Information System (INIS)

Dwarkanath, Bilikere S.; Zolzer, Frido; Chandana, Sudhir; Bauch, Thomas; Adhikari, Jawahar S.; Muller, Wolfgang U.; Streffer, Christian; Jain, Viney

2001-01-01

Purpose: The glucose analog and glycolytic inhibitor, 2-deoxy-D-glucose (2-DG), has been shown to differentially enhance the radiation damage in tumor cells by inhibiting the postirradiation repair processes. The present study was undertaken to examine the relationship between 2-DG-induced modification of energy metabolism and cellular radioresponses and to identify the most relevant parameter(s) for predicting the tumor response to the combined treatment of radiation + 2-DG. Methods and Materials: Six human tumor cell lines (glioma: BMG-1 and U-87, squamous cell carcinoma: 4451 and 4197, and melanoma: MeWo and Be-11) were investigated. Cells were exposed to 2 Gy of Co-60 γ-rays or 250 kVP X-rays and maintained under liquid-holding conditions 2-4 h to facilitate repair. 2-DG (5 mM, equimolar with glucose) that was added at the time of irradiation was present during the liquid holding. Glucose utilization, lactate production (enzymatic assays), and adenine nucleotides (high performance liquid chromatography and capillary isotachophoresis) were investigated as parameters of energy metabolism. Induction and repair of DNA damage (comet assay), cytogenetic damage (micronuclei formation), and cell death (macrocolony assay) were analyzed as parameters of radiation response. Results: The glucose consumption and lactate production of glioma cell lines (BMG-1 and U-87) were nearly 2-fold higher than the squamous carcinoma cell lines (4197 and 4451). The ATP content varied from 3.0 to 6.5 femto moles/cell among these lines, whereas the energy charge (0.86-0.90) did not show much variation. Presence of 2-DG inhibited the rate of glucose usage and glycolysis by 30-40% in glioma cell lines and by 15-20% in squamous carcinoma lines, while ATP levels reduced by nearly 40% in all the four cell lines. ATP:ADP ratios decreased to a greater extent (∼40%) in glioma cells than in squamous carcinoma 4451 and MeWo cells; in contrast, presence of 2-DG reduced ADP:AMP ratios by 3-fold in

Complete analytic results for radiative-recoil corrections to ground-state muonium hyperfine splitting

International Nuclear Information System (INIS)

Karshenboim, S.G.; Shelyuto, V.A.; Eides, M.E.

1988-01-01

Analytic expressions are obtained for radiative corrections to the hyperfine splitting related to the muon line. The corresponding contribution amounts to (Z 2 a) (Za) (m/M) (9/2 ζ(3) - 3π 2 ln 2 + 39/8) in units of the Fermi hyperfine splitting energy. A complete analytic result for all radiative-recoil corrections is also presented

Effects of radiation and porphyrin on mitosis and chromosomes in human hematopoietic cell lines

International Nuclear Information System (INIS)

Tan, J.C.; Huang, C.C.; Fiel, R.J.

1976-01-01

The effect on mitosis of a human hematopoietic cell line RPMI-1788 treated with a metal chelate (Zn ++ ) of meso-tetra (p-carboxyphenyl) porphine (Zn-TCPP) alone at various concentrations or in combination with gamma-irradiation at various doses were studied. The results showed that both Zn-TCPP and radiation were effective in interfering with normal mitosis and that the effect of radiation was relatively more effective. Data also suggest interacting effects between Zn-TCPP and gamma-irradiation. At low doses of radiation, Zn-TCPP potentiated the effect of radiation. The reverse seemed to be true at a high dose of radiation. The effects of two porphyrins (Zn-TCPP and hematoporphyrin) and radiation on chromosomes were also studied. Chromosomal aberrations characteristic of radiation were observed. The porphyrins were found not to be effective chromosome-breaking agents under the experimental conditions tested

Gamma-ray lines from radiative dark matter decay

International Nuclear Information System (INIS)

Garny, Mathias; Ibarra, Alejandro; Tran, David; Weniger, Christoph

2011-01-01

The decay of dark matter particles which are coupled predominantly to charged leptons has been proposed as a possible origin of excess high-energy positrons and electrons observed by cosmic-ray telescopes PAMELA and Fermi LAT. Even though the dark matter itself is electrically neutral, the tree-level decay of dark matter into charged lepton pairs will generically induce radiative two-body decays of dark matter at the quantum level. Using an effective theory of leptophilic dark matter decay, we calculate the rates of radiative two-body decays for scalar and fermionic dark matter particles. Due to the absence of astrophysical sources of monochromatic gamma rays, the observation of a line in the diffuse gamma-ray spectrum would constitute a strong indication of a particle physics origin of these photons. We estimate the intensity of the gamma-ray line that may be present in the energy range of a few TeV if the dark matter decay interpretation of the leptonic cosmic-ray anomalies is correct and comment on observational prospects of present and future Imaging Cherenkov Telescopes, in particular the CTA

Induction of chromosome aberrations in two lines of cultured cells using different types of radiation

International Nuclear Information System (INIS)

Zoetelief, J.; Dingjan-Hirschi, E.S.; Hasper, J.; Janse, H.C.; Barendsen, G.W.

The induction of chromosome aberrations has been investigated in two lines of cultured cells for different types of radiation. The obtained results are compared with information on induction of cell reproductive death and malignant transformation. (Auth.)

Differential responses to radiation and hyperthermia of cloned cell lines derived from a single human melanoma xenograft

International Nuclear Information System (INIS)

Rofstad, E.K.; Brustad, T.

1984-01-01

One uncloned and five cloned cell lines were derived from a single human melanoma xenograft. Cells from passages 7-12 were exposed to either radiation or hyperthermia (42.5 0 C, pH = 7.4) under aerobic conditions and the colony forming ability of the cells was assayed in soft agar. The five cloned lines showed individual and characteristic responses to radiation as well as to hyperthermia. The variation in the response to radiation was mainly reflected in the size of the shoulders of the survival curves rather than in the D 0 -values. The variation in the response to hyperthermia was mainly reflected in the terminal slopes of the survival curves. The survival curve of cells from the uncloned line, both when exposed to radiation and hyperthermia, was positioned in the midst of those of the cloned lines. The response of the cloned lines to radiation did not correlate with the response to hyperthermia, indicating that tumor cell subpopulations which are resistant to radiation may respond well to hyperthermia

Effect of recombinant adenovirus encoding human p53 tumor suppressor gene combined with radiation therapy on human lymphoma cells lines

International Nuclear Information System (INIS)

Yu Zeyang; Fan Wo; Li Dongqing; Zhu Ran; Wan Jianmei; Wang Yongqing; Wu Jinchang

2008-01-01

This paper analyzes the inhibitory effect and radiation sensitization of recombinant adenovirus encoding human p53 tumor suppressor gene (rAd-p53) on human lymphoma cell lines. Human lymphoma cell lines were treated with rAd-p53, radiation therapy and combined treatment, respectively. The cell growth inhibition was assessed by MTF. The cell cycle and apoptosis were detected by flow cytometry, and the p53 protein expression was detected by Western blotting. The results showed that extrinsic p53 gene have expressed to some degree, but not at high level. The role of inhibition and radiation sensitivity of rAd-p53 was not significant to human lymphoma cell lines. (authors)

Experimental studies on coherent synchrotron radiation at an emittance exchange beam line

Science.gov (United States)

Thangaraj, J. C. T.; Thurman-Keup, R.; Ruan, J.; Johnson, A. S.; Lumpkin, A. H.; Santucci, J.

2012-11-01

One of the goals of the Fermilab A0 photoinjector is to investigate experimentally the transverse to longitudinal emittance exchange (EEX) principle. Coherent synchrotron radiation in the emittance exchange line could limit the performance of the emittance exchanger at short bunch lengths. In this paper, we present experimental and simulation studies of the coherent synchrotron radiation (CSR) in the emittance exchange line at the A0 photoinjector. We report on time-resolved CSR studies using a skew-quadrupole technique. We also demonstrate the advantages of running the EEX with an energy-chirped beam.

Use of lymphoblastoid cell lines to evaluate the hypersensitivity to ultraviolet radiation in Cockayne syndrome

International Nuclear Information System (INIS)

Otsuka, F.; Tarone, R.E.; Cayeux, S.; Robbins, J.H.

1984-01-01

Cockayne syndrome (CS) is a rare autosomal recessive disease characterized by acute sun sensitivity, cachectic dwarfism, and neurologic and skeletal abnormalities. Cultured skin fibroblasts from patients with this disease are known to be hypersensitive to the lethal effects of 254-nm UV radiation. The authors have studied the sensitivity of 254-nm UV radiation of lymphoblastoid lines derived from 3 typical CS patients, 1 atypical CS patient who had a very late age of onset of clinical manifestations, 2 patients who had both xeroderma pigmentosum (XP) and typical CS, and 3 heterozygous parents of these patients. Post-UV survival was determined by the trypan-blue dye-exclusion method. The lymphoblastoid lines from the 3 typical CS patients, the atypical CS patient, and the 2 patients with both CS and XP had decreased post-UV viability in comparison with lines from normal donors. Lines from the heterozygous parents had normal post-UV viability. The post-UV viability of the typical CS lines was similar to that of a XP complementation group C line. The relative post-UV viability of lymphoblastoid lines from the typical CS patients was similar to the relative post-UV survival of their fibroblast lines. The lymphoblastoid line from the atypical CS patient had a post-UV viability similar to that of the typical CS patients. Thus, the relative hypersensitivity of CS patients cells in vitro does not reflect the severity or age of onset of the patients clinical manifestations. The lymphoblastoid lines from the 2 patients who had both CS and XP were significantly more sensitive to the UV radiation than those from patients with only CS. Our studies demonstrate that lymphoblastoid lines from patients with CS are appropriate and useful cell lines for the study of the inherited hypersensitivity to UV radiation

Transcriptome-wide studies of prostate cancer cell lines in the context of medical radiation

International Nuclear Information System (INIS)

Hammer, Paul

2012-01-01

The use of radiotherapy in addition to chemotherapy and surgical removal is the most powerful instrument in the fight against malignant tumors in cancer medicine. After cardiovascular diseases, cancer is the second leading cause of death in the western world, in which prostate cancer is the most frequent male cancer. Despite continuous technological improvements in radiological instruments and prognosis, it may occur a recurrence up to many years after radiotherapy due to a high resistance capability of individual malignant cells of the locally occurring tumor. Although modern radiation biology has studied many aspects of the resistance mechanisms, questions are largely unanswered especially in regards to prognostic terms and time response of tumor cells to ionizing radiation. As cellular models four prostate cancer cell lines with different radiation sensitivities (PC3, DuCaP, DU-145, RWPE-1) were cultured and tested for their ability to survive after exposure to ionizing radiation by a trypane blue and MTT viability assay. The proliferative capacity of the four cell lines was determined using a colony formation assay. The PC3 cell line (radiation-resistant) and the DuCaP cell line (radiation-sensitive) showed the maximal differences in terms of radiation sensitivity. Based on these results the two cell lines were selected to allow identification of potential prognostic marker for predicting the effectiveness of radiation therapy via their transcriptome-wide gene expression. Furthermore, a time series experiment with the radiation-resistant PC3 cell line was performed. At 8 different time points, during the period from 00:00 - 42:53 (hh:mm) after exposure with 1 Gy, the mRNA was quantified by next generation sequencing to investigate the dynamic behavior of time-delayed gene expression and to discover resistance mechanisms. Of 10,966 expressed genes 730 were significant differentially expressed, determined by setting a fold change threshold in conjunction with a P

Applications of the energy differentiation type radiation line sensor to such as inspection for the plumbing corrosion

International Nuclear Information System (INIS)

Tomita, Yasuhiro; Shirayanagi, Yuji; Matsui, Shinjiro; Kamiya, Yosuke; Kobayashi, Akira

2015-01-01

The authors have engaged in development of the next-generation radiation detectors that can give information on energy such as X-rays and γ-rays, and commercialized an energy discrimination type radiation line sensor capable of discriminating the energy of photons using a CdTe radiation detector element. This paper introduces the structure and principles of this energy discrimination type radiation line sensor. As the basic application, it also introduces the material identification, energy discrimination type X-ray CT imaging, and the quantitative determination of iron plate thickness using X-ray. In addition, it introduces the radiation line sensor we have developed for inspecting the reduced amount of wall thickness of piping with insulation materials. This radiation line sensor for pipe thinning inspection combined with radiation sources (X-rays, γ-rays) and a transport system is capable of accurately and efficiently inspecting reduced wall thickness, while moving the censor on the covered pipe with heat insulating materials through remote control, without removing piping insulation materials and without stopping the use of piping. (A.O.)

Computer controlled vacuum control system for synchrotron radiation beam lines

International Nuclear Information System (INIS)

Goldberg, S.M.; Wang, C.; Yang, J.

1983-01-01

The increasing number and complexity of vacuum control systems at the Stanford Synchrotron Radiation Laboratory has resulted in the need to computerize its operations in order to lower costs and increase efficiency of operation. Status signals are transmitted through digital and analog serial data links which use microprocessors to monitor vacuum status continuously. Each microprocessor has a unique address and up to 256 can be connected to the host computer over a single RS232 data line. A FORTRAN program on the host computer will request status messages and send control messages via only one RS232 line per beam line, signal the operator when a fault condition occurs, take automatic corrective actions, warn of impending valve failure, and keep a running log of all changes in vacuum status for later recall. Wiring costs are thus greatly reduced and more status conditions can be monitored without adding excessively to the complexity of the system. Operators can then obtain status reports at various locations in the lab quickly without having to read a large number of meter and LED's

Experimental studies on coherent synchrotron radiation at an emittance exchange beam line

Directory of Open Access Journals (Sweden)

J. C. T. Thangaraj

2012-11-01

Full Text Available One of the goals of the Fermilab A0 photoinjector is to investigate experimentally the transverse to longitudinal emittance exchange (EEX principle. Coherent synchrotron radiation in the emittance exchange line could limit the performance of the emittance exchanger at short bunch lengths. In this paper, we present experimental and simulation studies of the coherent synchrotron radiation (CSR in the emittance exchange line at the A0 photoinjector. We report on time-resolved CSR studies using a skew-quadrupole technique. We also demonstrate the advantages of running the EEX with an energy-chirped beam.

Line-driven disk winds in active galactic nuclei: The critical importance of ionization and radiative transfer

Energy Technology Data Exchange (ETDEWEB)

Higginbottom, Nick; Knigge, Christian; Matthews, James H. [School of Physics and Astronomy, University of Southampton, Highfield, Southampton, SO17 1BJ (United Kingdom); Proga, Daniel [Department of Physics and Astronomy, University of Nevada, Las Vegas, 4505 South Maryland Parkway, Las Vegas, NV 89154-4002 (United States); Long, Knox S. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Sim, Stuart A., E-mail: nick_higginbottom@fastmail.fm [School of Mathematics and Physics, Queens University Belfast, University Road, Belfast, BT7 1NN (United Kingdom)

2014-07-01

Accretion disk winds are thought to produce many of the characteristic features seen in the spectra of active galactic nuclei (AGNs) and quasi-stellar objects (QSOs). These outflows also represent a natural form of feedback between the central supermassive black hole and its host galaxy. The mechanism for driving this mass loss remains unknown, although radiation pressure mediated by spectral lines is a leading candidate. Here, we calculate the ionization state of, and emergent spectra for, the hydrodynamic simulation of a line-driven disk wind previously presented by Proga and Kallman. To achieve this, we carry out a comprehensive Monte Carlo simulation of the radiative transfer through, and energy exchange within, the predicted outflow. We find that the wind is much more ionized than originally estimated. This is in part because it is much more difficult to shield any wind regions effectively when the outflow itself is allowed to reprocess and redirect ionizing photons. As a result, the calculated spectrum that would be observed from this particular outflow solution would not contain the ultraviolet spectral lines that are observed in many AGN/QSOs. Furthermore, the wind is so highly ionized that line driving would not actually be efficient. This does not necessarily mean that line-driven winds are not viable. However, our work does illustrate that in order to arrive at a self-consistent model of line-driven disk winds in AGN/QSO, it will be critical to include a more detailed treatment of radiative transfer and ionization in the next generation of hydrodynamic simulations.

The indirect effect of radiation reduces the repair fidelity of NHEJ as verified in repair deficient CHO cell lines exposed to different radiation qualities and potassium bromate

International Nuclear Information System (INIS)

Bajinskis, Ainars; Olsson, Gunilla; Harms-Ringdahl, Mats

2012-01-01

The complexity of DNA lesions induced by ionizing radiation is mainly dependent on radiation quality, where the indirect action of radiation may contribute to different extent depending on the type of radiation under study. The effect of indirect action of radiation can be investigated by using agents that induce oxidative DNA damage or by applying free radical scavengers. The aim of this study was to investigate the role of the indirect effect of radiation for the repair fidelity of non-homologous end-joining (NHEJ), homologous recombination repair (HRR) and base excision repair (BER) when DNA damage of different complexity was induced by gamma radiation, alpha particles or from base damages (8-oxo-dG) induced by potassium bromate (KBrO 3 ). CHO cells lines deficient in XRCC3 (HRR) irs1SF, XRCC7 (NHEJ) V3-3 and XRCC1 (BER) EM9 were irradiated in the absence or presence of the free radical scavenger dimethyl sulfoxide (DMSO). The endpoints investigated included rate of cell proliferation by the DRAG assay, clonogenic cell survival and the level of primary DNA damage by the comet assay. The results revealed that the indirect effect of low-LET radiation significantly reduced the repair fidelity of both NHEJ and HRR pathways. For high-LET radiation the indirect effect of radiation also significantly reduced the repair fidelity for the repair deficient cell lines. The results suggest further that the repair fidelity of the error prone NHEJ repair pathway is more impaired by the indirect effect of high-LET radiation relative to the other repair pathways studied. The response to bromate observed for the two DSB repair deficient cell lines strongly support earlier studies that bromate induces complex DNA damages. The significantly reduced repair fidelity of irs1SF and V3-3 suggests that NHEJ as well as HRR are needed for the repair, and that complex DSBs are formed after bromate exposure.

The indirect effect of radiation reduces the repair fidelity of NHEJ as verified in repair deficient CHO cell lines exposed to different radiation qualities and potassium bromate.

Science.gov (United States)

Bajinskis, Ainars; Olsson, Gunilla; Harms-Ringdahl, Mats

2012-03-01

The complexity of DNA lesions induced by ionizing radiation is mainly dependent on radiation quality, where the indirect action of radiation may contribute to different extent depending on the type of radiation under study. The effect of indirect action of radiation can be investigated by using agents that induce oxidative DNA damage or by applying free radical scavengers. The aim of this study was to investigate the role of the indirect effect of radiation for the repair fidelity of non-homologous end-joining (NHEJ), homologous recombination repair (HRR) and base excision repair (BER) when DNA damage of different complexity was induced by gamma radiation, alpha particles or from base damages (8-oxo-dG) induced by potassium bromate (KBrO(3)). CHO cells lines deficient in XRCC3 (HRR) irs1SF, XRCC7 (NHEJ) V3-3 and XRCC1 (BER) EM9 were irradiated in the absence or presence of the free radical scavenger dimethyl sulfoxide (DMSO). The endpoints investigated included rate of cell proliferation by the DRAG assay, clonogenic cell survival and the level of primary DNA damage by the comet assay. The results revealed that the indirect effect of low-LET radiation significantly reduced the repair fidelity of both NHEJ and HRR pathways. For high-LET radiation the indirect effect of radiation also significantly reduced the repair fidelity for the repair deficient cell lines. The results suggest further that the repair fidelity of the error prone NHEJ repair pathway is more impaired by the indirect effect of high-LET radiation relative to the other repair pathways studied. The response to bromate observed for the two DSB repair deficient cell lines strongly support earlier studies that bromate induces complex DNA damages. The significantly reduced repair fidelity of irs1SF and V3-3 suggests that NHEJ as well as HRR are needed for the repair, and that complex DSBs are formed after bromate exposure. Copyright © 2011 Elsevier B.V. All rights reserved.

The indirect effect of radiation reduces the repair fidelity of NHEJ as verified in repair deficient CHO cell lines exposed to different radiation qualities and potassium bromate

Energy Technology Data Exchange (ETDEWEB)

Bajinskis, Ainars, E-mail: ainars.bajinskis@gmt.su.se [Centre for Radiation Protection Research, Department of Genetics, Microbiology and Toxicology, Stockholm University, S-10691 Stockholm (Sweden); Olsson, Gunilla; Harms-Ringdahl, Mats [Centre for Radiation Protection Research, Department of Genetics, Microbiology and Toxicology, Stockholm University, S-10691 Stockholm (Sweden)

2012-03-01

The complexity of DNA lesions induced by ionizing radiation is mainly dependent on radiation quality, where the indirect action of radiation may contribute to different extent depending on the type of radiation under study. The effect of indirect action of radiation can be investigated by using agents that induce oxidative DNA damage or by applying free radical scavengers. The aim of this study was to investigate the role of the indirect effect of radiation for the repair fidelity of non-homologous end-joining (NHEJ), homologous recombination repair (HRR) and base excision repair (BER) when DNA damage of different complexity was induced by gamma radiation, alpha particles or from base damages (8-oxo-dG) induced by potassium bromate (KBrO{sub 3}). CHO cells lines deficient in XRCC3 (HRR) irs1SF, XRCC7 (NHEJ) V3-3 and XRCC1 (BER) EM9 were irradiated in the absence or presence of the free radical scavenger dimethyl sulfoxide (DMSO). The endpoints investigated included rate of cell proliferation by the DRAG assay, clonogenic cell survival and the level of primary DNA damage by the comet assay. The results revealed that the indirect effect of low-LET radiation significantly reduced the repair fidelity of both NHEJ and HRR pathways. For high-LET radiation the indirect effect of radiation also significantly reduced the repair fidelity for the repair deficient cell lines. The results suggest further that the repair fidelity of the error prone NHEJ repair pathway is more impaired by the indirect effect of high-LET radiation relative to the other repair pathways studied. The response to bromate observed for the two DSB repair deficient cell lines strongly support earlier studies that bromate induces complex DNA damages. The significantly reduced repair fidelity of irs1SF and V3-3 suggests that NHEJ as well as HRR are needed for the repair, and that complex DSBs are formed after bromate exposure.

Radiation source states on-line supervision system design and implementation based on RFID technology

International Nuclear Information System (INIS)

Yang Binhua; Ling Qiu; Yin Guoli; Yang Kun; Wan Xueping; Wang Kan

2011-01-01

It puts forward radiation source states on-line monitoring resolution based on RFID technology. Firstly, the system uses RFID in real-time transmission of the radiation dose rate, and monitors the radiation source states and dose rate of the surrounding environment on-line. Then it adopts regional wireless networking mode to construct enterprise level monitoring network, which resolves long-distance wiring problems. And then it uses GPRS wireless to transport the real-time data to the monitoring center and the government supervision department, By adopting randomly dynamic cording in display update every day, it strengthens the supervision of the radiation source. At last this system has been successful applied to a thickness gauge project, which verifies the feasibility and practicality is good. (authors)

Radiation-induced alterations of histone post-translational modification levels in lymphoblastoid cell lines

International Nuclear Information System (INIS)

Maroschik, Belinda; Gürtler, Anne; Krämer, Anne; Rößler, Ute; Gomolka, Maria; Hornhardt, Sabine; Mörtl, Simone; Friedl, Anna A

2014-01-01

Radiation-induced alterations in posttranslational histone modifications (PTMs) may affect the cellular response to radiation damage in the DNA. If not reverted appropriately, altered PTM patterns may cause long-term alterations in gene expression regulation and thus lead to cancer. It is therefore important to characterize radiation-induced alterations in PTM patterns and the factors affecting them. A lymphoblastoid cell line established from a normal donor was used to screen for alterations in methylation levels at H3K4, H3K9, H3K27, and H4K20, as well as acetylation at H3K9, H3K56, H4K5, and H4K16, by quantitative Western Blot analysis at 15 min, 1 h and 24 h after irradiation with 2 Gy and 10 Gy. The variability of alterations in acetylation marks was in addition investigated in a panel of lymphoblastoid cell lines with differing radiosensitivity established from lung cancer patients. The screening procedure demonstrated consistent hypomethylation at H3K4me3 and hypoacetylation at all acetylation marks tested. In the panel of lymphoblastoid cell lines, however, a high degree of inter-individual variability became apparent. Radiosensitive cell lines showed more pronounced and longer lasting H4K16 hypoacetylation than radioresistant lines, which correlates with higher levels of residual γ-H2AX foci after 24 h. So far, the factors affecting extent and duration of radiation-induced histone alterations are poorly defined. The present work hints at a high degree of inter-individual variability and a potential correlation of DNA damage repair capacity and alterations in PTM levels

Generalized transmission line method to study the far-zone radiation of antennas under a multilayer structure

CERN Document Server

Wu, Xuan Hui

2008-01-01

This book gives a step-by-step presentation of a generalized transmission line method to study the far-zone radiation of antennas under a multilayer structure. Normally, a radiation problem requires a full wave analysis which may be time consuming. The beauty of the generalized transmission line method is that it transforms the radiation problem for a specific type of structure, say the multilayer structure excited by an antenna, into a circuit problem that can be efficiently analyzed. Using the Reciprocity Theorem and far-field approximation, the method computes the far-zone radiation due to

GARLIC, a shielding program for GAmma Radiation from Line- and Cylinder-sources

Energy Technology Data Exchange (ETDEWEB)

Roos, Matts

1959-07-15

GARLIC is a program for computing the gamma ray flux or dose rate at a shielded idotropic point detector, due to a line source or the line equivalent of a cylindrical source. The source strength distribution along the line must be either uniform or an arbitrary part of the positive half-cycle of a cosine function. The line source can be oriented arbitrarily with respect to the main shield and the detector, except that the detector must not be located on the line source or on its extension. The main source is a homogeneous plane slab in which scattered radiation is accounted for by multiplying each point element of the line source by a point source build-up factor inside the integral over the point elements. Between, the main shield and the line source additional shields can be introduced, which are either plane slabs, parallel to the main shield, or cylindrical rings, coaxial with the line source. Scattered radiation in the additional shields can only be accounted for by constant build-up factors outside the integral. GARLIC-xyz is an extended version particularly suited for the frequently met problem of shielding a room containing a large number of line sources in different positions. The program computes the angles and linear dimensions of a problem for GARLIC when the positions of the detector point and the end points of the line source are given as points in an arbitrary rectangular coordinate system. As an example the isodose curves in water are presented for a monoenergetic cosine-distributed line source at several source energies and for an operating fuel element of the Swedish reactor R3.

Expression of Ku correlates with radiation sensitivities in the head and neck cancer cell lines

International Nuclear Information System (INIS)

Lee, Sang Wook; Yu, Eun Sil; Yi, So Lyoung; Son, Se Hee; Kim, Jong Hoon; Ahn, Seung Do; Shin, Seong Soo; Choi, Eun Kyung

2004-01-01

DNA-dependent protein kinase (DNA-PK) is a serine/threonine kinase consisting of a 470 kDa catalytic subunit (DNA-PKcs) and a heterodimeric regulatory complex, called Ku, which is composed of 70 kDa (Ku 70) and 86 kDa (Ku 80) proteins. The DNA-PK has been shown to play a pivotal role in rejoining DNA double-strand-breaks (dsb) in mammalian cells. The purpose of this study is to examine the relationship between the level of Ku expression and radiation sensitivity. Nine head and neck, cancer cell lines showed various intrinsic radiation sensitivities. Among the nine, AMC-HN-3 cell was the most sensitive for X-ray irradiation and AMC-HN-9 cell was the most resistance. The most sensitive and resistant cell lines were selected and the test sensitivity of radiation and expression of Ku were measured. Radiation sensitivity was obtained by colony forming assay and Ku protein expression using Western blot analysis. Ku80 increased expression by radiation, wheras Ku70 did not. Overexpression of Ku80 protein increased radiation resistance in AMC-HN9 cell line. There was a correlation between Ku80 expression and radiation resistance. Ku80 was shown to play an important role in radiation damage response. Induction of Ku80 expression had an important role in DNA damage repair by radiation. Ku80 expression may be an effective predictive assay of radiosensitivity on head and neck cancer

Radiation induction of drug resistance in RIF-1: Correlation of tumor and cell culture results

International Nuclear Information System (INIS)

Moulder, J.E.; Hopwood, L.E.; Volk, D.M.; Davies, B.M.

1991-01-01

The RIF-1 tumor line contains cells that are resistant to various anti-neoplastic drugs, including 5-fluorouracil (5FU), methotrexate (MTX), adriamycin (ADR), and etoposide (VP16). The frequency of these drug-resistant cells is increased after irradiation. The frequency of drug-resistant cells and the magnitude of radiation-induced drug resistance are different in cell culture than in tumors. The dose-response and expression time relationships for radiation induction of drug resistance observed in RIF-1 tumors are unusual.We hypothesize that at high radiation doses in vivo, we are selecting for cells that are both drug resistant and radiation resistant due to microenvironmental factors, whereas at low radiation doses in vivo and all radiation doses in vitro, we are observing true mutants. These studies indicate that there can be significant differences in drug-resistance frequencies between tumors and their cell lines of origin, and that radiation induction of drug resistance depends significantly on whether the induction is done in tumors or in cell culture. These results imply that theories about the induction of drug resistance that are based on cell culture studies may be inapplicable to the induction of drug resistance in tumors

Cell fusion induced by ionizing radiation in various cell lines

International Nuclear Information System (INIS)

Khair, M.B.

1994-07-01

Cell fusion induced by ionizing radiation has been studied in rat's hepatocytes in vivo and in different cell lines in vitro. These cell lines were: Hela cells, V-79 fibroblasts, human and rat lymphocytes. For irradiation, 0.85 MeV fission neutrons and 14 MeV fast neutrons were used. Cell analyses were performed by fluorescent dyes using immunofluorescent microscope and flow cytometre. Our results in vivo showed that, regardless the dose-rate, a dose of 1 Gy approximately was enough to induce a significant level of cell fusion depending on neutron energy and the age of rats. The level of cell fusion was also significant in Hela cells at a dose of 0.5 Gy. Similar effect, but to a lesser extent, was observed in V-79 cells. Whereas, in lymphocytes insignificant cell fusion was noticed. The varying levels of cell-fusion in different cell lines could be attributed to the type of cells and mutual contact between cells. Furthermore irradiation did not show any influence on cell division ability in both hepatocytes and Hela cells and that fused cells were also able to divide forming a new generation of cells. (author). 36 refs., 8 figs., 10 tabs

Andrographolide radiosensitizes human esophageal cancer cell line ECA109 to radiation in vitro.

Science.gov (United States)

Wang, Z-M; Kang, Y-H; Yang, X; Wang, J-F; Zhang, Q; Yang, B-X; Zhao, K-L; Xu, L-P; Yang, L-P; Ma, J-X; Huang, G-H; Cai, J; Sun, X-C

2016-01-01

To explore the radiosensitivity of andrographolide on esophageal cancer cell line ECA109. The inhibition effects of andrographolide were measured using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium (MTT) assay. Clonogenic survival assay was used to evaluate the effects of andrographolide on the radiosensitivity of esophageal cancer cells. Immunofluorescence was employed to examine Bax expression. The changes in cell cycle distribution and apoptosis were assayed using flow cytometry. The expression of NF-κb/Cleaved-Caspase3/Bax/Bcl-2 was measured using Western blot analysis. DNA damage was detected via γ-H2AX foci counting. With a clear dose and time effects, andrographolide was found to inhibit the proliferation of esophageal cell line ECA109. The results of the clonogenic survival assay show that andrographolide could markedly enhance radiosensitivity (P Andrographolide caused a dose-dependent increase in Cleaved-Caspase3/Bax protein expression and a decrease in Bcl-2/NF-κb expression. Apoptosis in andrographolide-treated ECA-109 increased significantly compared with the apoptosis in the simple drug and radiation combined with drug groups (P andrographolide combined with radiation group increased the number of DNA double chain breaks. Andrographolide can increase the radiosensitivity of esophageal cell line ECA109. This result may be associated with the decrease in the NF-κb level and the induced apoptosis of esophageal cancer cells. © 2014 International Society for Diseases of the Esophagus.

Fried-Yennie gauge recalculation of the electron line induced radiative-recoil corrections to muonium hyperfine splitting

International Nuclear Information System (INIS)

Brook, V.Yu.; Eides, M.I.; Karshenboim, S.G.; Shelyuto, V.A.

1989-01-01

A new analytic calculation of radiative-recoil corrections to muonium ground-state hyperfine splitting induced by electron line insertions is performed. The starting point of this calculation is presented by the Fried-Yennie gauge expression for the electron line factor. The final result confirms the one obtained previously from the apparently different expression in the Feynman gauge and removes the slight discrepancy which existed in the literature between the calculations in different gauges. (orig.)

Polarisation of auroral emission lines in the Earth's upper atmosphere : first results and perspectives

Science.gov (United States)

Lamy, H.; Barthelemy, M.; Simon Wedlund, C.; Lilensten, J.; Bommier, V.

2011-12-01

Polarisation of light is a key observable to provide information about asymmetry or anisotropy within a radiative source. Following the pioneering and controversial work of Duncan in 1959, the polarisation of auroral emission lines in the Earth's upper atmosphere has been overlooked for a long time, even though the red intense auroral line (6300Å) produced by collisional impacts with electrons precipitating along magnetic field lines is a good candidate to search for polarisation. This problem was investigated again by Lilensten et al (2006) and observations were obtained by Lilensten et al (2008) confirming that the red auroral emission line is polarised. More recent measurements obtained by Barthélemy et al (2011) are presented and discussed. The results are compared to predictions of the theoretical work of Bommier et al (2011) and are in good agreement. Following these encouraging results, a new dedicated spectropolarimeter is currently under construction between BIRA-IASB and IPAG to provide simultaneously the polarisation of the red line and of other interesting auroral emission lines such as N2+ 1NG (4278Å), other N2 bands, etc... Perspectives regarding the theoretical polarisation of some of these lines will be presented. The importance of these polarisation measurements in the framework of atmospheric modeling and geomagnetic activity will be discussed.

Effects of external radiation fields on line emission—application to star-forming regions

Energy Technology Data Exchange (ETDEWEB)

Chatzikos, Marios; Ferland, G. J. [University of Kentucky, Lexington, KY 40506 (United States); Williams, R. J. R. [AWE plc, Aldermaston, Reading RG7 4PR (United Kingdom); Porter, Ryan [Department of Physics and Astronomy and Center for Simulational Physics, University of Georgia, Athens, GA 30602-2451 (United States); Van Hoof, P. A. M., E-mail: mchatzikos@gmail.com [Royal Observatory of Belgium, Avenue Circulaire 3, B-1180 Uccle (Belgium)

2013-12-20

A variety of astronomical environments contain clouds irradiated by a combination of isotropic and beamed radiation fields. For example, molecular clouds may be irradiated by the isotropic cosmic microwave background, as well as by a nearby active galactic nucleus. These radiation fields excite atoms and molecules and produce emission in different ways. We revisit the escape probability theorem and derive a novel expression that accounts for the presence of external radiation fields. We show that when the field is isotropic the escape probability is reduced relative to that in the absence of external radiation. This is in agreement with previous results obtained under ad hoc assumptions or with the two-level system, but can be applied to complex many-level models of atoms or molecules. This treatment is in the development version of the spectral synthesis code CLOUDY. We examine the spectrum of a Spitzer cloud embedded in the local interstellar radiation field and show that about 60% of its emission lines are sensitive to background subtraction. We argue that this geometric approach could provide an additional tool toward understanding the complex radiation fields of starburst galaxies.

Sensitivity to ionizing radiation and chemotherapeutic agents in gemcitabine-resistant human tumor cell lines

International Nuclear Information System (INIS)

Bree, Chris van; Kreder, Natasja Castro; Loves, Willem J.P.; Franken, Nicolaas A.P.; Peters, Godefridus J.; Haveman, Jaap

2002-01-01

Purpose: To determine cross-resistance to anti-tumor treatments in 2',2'difluorodeoxycytidine (dFdC, gemcitabine)-resistant human tumor cells. Methods and Materials: Human lung carcinoma cells SW-1573 (SWp) were made resistant to dFdC (SWg). Sensitivity to cisplatin (cDDP), paclitaxel, 5-fluorouracil (5-FU), methotrexate (MTX), cytarabine (ara-C), and dFdC was measured by a proliferation assay. Radiosensitivity and radioenhancement by dFdC of this cell panel and the human ovarian carcinoma cell line A2780 and its dFdC-resistant variant AG6000 were determined by clonogenic assay. Bivariate flowcytometry was performed to study cell cycle changes. Results: In the SWg, a complete deoxycytidine kinase (dCK) deficiency was found on mRNA and protein level. This was accompanied by a 10-fold decrease in dCK activity which resulted in the >1000-fold resistance to dFdC. Sensitivity to other anti-tumor drugs was not altered, except for ara-C (>100-fold resistance). Radiosensitivity was not altered in the dFdC-resistant cell lines SWg and AG6000. High concentrations (50-100 μM dFdC) induced radioenhancement in the dFdC-resistant cell lines similar to the radioenhancement obtained at lower concentrations (10 nM dFdC) in the parental lines. An early S-phase arrest was found in all cell lines after dFdC treatment where radioenhancement was achieved. Conclusions: In the dFdC-resistant lung tumor cell line SWg, the deficiency in dCK is related to the resistance to dFdC and ara-C. No cross-resistance was observed to other anti-tumor drugs used for the treatment in lung cancer. Sensitivity to ionizing radiation was not altered in two different dFdC-resistant cell lines. Resistance to dFdC does not eliminate the ability of dFdC to sensitize cells to radiation

Preliminary Results on Design and Implementation of a Solar Radiation Monitoring System

Directory of Open Access Journals (Sweden)

Lorentz Jäntschi

2008-02-01

Full Text Available The paper presents a solar radiation monitoring system, using two scientificpyranometers and an on-line computer home-made data acquisition system. The firstpyranometer measures the global solar radiation and the other one, which is shaded,measure the diffuse radiation. The values of total and diffuse solar radiation arecontinuously stored into a database on a server. Original software was created for dataacquisition and interrogation of the created system. The server application acquires the datafrom pyranometers and stores it into a database with a baud rate of one record at 50seconds. The client-server application queries the database and provides descriptivestatistics. A web interface allow to any user to define the including criteria and to obtainthe results. In terms of results, the system is able to provide direct, diffuse and totalradiation intensities as time series. Our client-server application computes also derivateheats. The ability of the system to evaluate the local solar energy potential is highlighted.

Analyzing the Health Risks Resulting from Extending the 400kV High Voltage Transmission Lines on the Human

Directory of Open Access Journals (Sweden)

Mohammed Hassan Dervish

2018-01-01

Full Text Available Although it is difficult to imagine life without electricity, there are compiling confirmations show thatexposure to magnetic fields correlated electricity and radio frequencies pose magnificent hazards to human health. The most economist method to transfer electricity from power generation stations to users is by measures of high power transmission lines, buoyed by big transmission towers. The cables laced between the towers radiate magnetic and electric fields. In this research study, the magnetic field at ground level under 400 kV network lines extended in residential places have been conducted in two ways, mathematical calculation and practical measurement then the obtained results analyzed and compared with the international standards reference values. the reason of chose this type of transmission line is frequently using. The results indicate that they fall within the safe limiter commended by the WorldHealth Organization. the strength of radiation increasing with high of sea level and moisture ratiobecause of air ionization.

Radiating nonuniform transmission-line systems and the partial element equivalent circuit method

CERN Document Server

Nitsch, Juergen; Wollenberg, Gunter

2009-01-01

High frequencies of densely packed modern electronic equipment turn even the smallest piece of wire into a transmission line with signal retardation, dispersion, attenuation, and distortion. In electromagnetic environments with high-power microwave or ultra-wideband sources, transmission lines pick up noise currents generated by external electromagnetic fields. These are superimposed on essential signals, the lines acting not only as receiving antennas but radiating parts of the signal energy into the environment. This book is outstanding in its originality. While many textbooks rephrase

The evaluation of radiation level and dose of workers in Guangzhou metro line 1

International Nuclear Information System (INIS)

Zhang Lin; Hu Canyun; Meng Xiaolian; He Zhan

2006-01-01

Objective: To find out the level of radiation and effective dose of workers in Guangzhou Metro line 1. Methods: In metro stations, external Gamma-ray exposure rates were obtained by FD-71A radiance measurer, 222 Rn and 220 Rn concentrations were obtained by using Rn-Tn solid state nuclear track detectors developed by The National Institute for Radiological Protection and Nuclear Safety, Chinese Centre for Disease Control. The annual Effective dose from Gamma, 222 Rn and 220 Rn were calculated. Results: The external Gamma-ray exposure average rate is 17.74 x 10 -8 Gy/h. The average concentration of 222 Rn is 59.8 Bq/m 3 . The average concentration of 220 Rn is 32.1 Bq/m 3 . The total annual effective dose from Gamma, 222 Rn and 220 Rn is 2.878 mSv/a. Conclusion: In the stations of Guangzhou in metro line 1, no more effective radiation dose to the workers has measured. (authors)

Cytotoxic effect and radiation enhancement of artemisinin in uterine cervical carcinoma cell line HeLa

International Nuclear Information System (INIS)

Gong Xiaomei; Zhou Daoan; Cao Jianping; Fan Saijun; Zhu Wei

2010-01-01

Objective: To investigate cytotoxic and radiosensitizing effect of Artemisinin on cervical carcinoma cell line HeLa. Methods: In order to measure the optimized effective time, cytotoxic effect of Artemisinin on HeLa cell line was investigated with MTT assay. The radiosensitization effect of different doses and different treatment duration of Artemisinin on HeLa cell line were evaluated by MTT test, the SER is 1.17 and radiosensitizing effect was measured with multi-target single hit model through SER of HeLa cell. Cell cycles in different groups were calculated by flow cytometry. Results: The 50% inhibition concentration of Artemisinin interacted with HeLa cells for 24 h is 600.19 nmol/ml, and for 48 h is 160.71 nmol/ml. The HeLa cells'surival ratio is 93.51%, 91.87%, and 87.28% after adding Atemisinin of 110.69 nmol/ml and 1 Gy radiation exposure. There are three groups: the chemotherapy only group, the radiotherapy only group and the combination group. The result of the cell cycles showed that cells in G 2 /M period decreased in the combination group. Conclusion: Artemisinin has radiosensitization effect on cervical carcinoma HeLa cells, whichshows dose and time dependent. Artemisinin can inhibit the G 2 /M block by ionizing radiation. (authors)

Radiation protective effect of hypoxia-inducible factor-1α (HIF-1α) on human oral squamous cell carcinoma cell lines

International Nuclear Information System (INIS)

Hosokawa, Y.; Okumura, K.; Terashima, S.; Sakakura, Y.

2012-01-01

We examined the effects of 5-Gy radiation on the expression of hypoxia-inducible factor-1α (HIF-1α) and the radiosensitivity of five human oral squamous cell carcinoma (OSCC) cell lines (SAS, Ca9-22, TT, BSC-OF and IS-FOM). In all of the cell lines, HIF-1α was expressed in mRNA, and radiation had no influence on gene transcription. The number of apoptotic cells increased 72 h after irradiation in cell lines SAS, Ca9-22 and TT cells, indicating low transcriptional levels of HIF-1α, and the levels of non-cleaved caspase-3, an executioner of apoptosis, and non-cleaved poly (adenosine diphosphate-ribose) polymerase (PARP), a marker of DNA damage early in apoptosis, decreased simultaneously. Conversely, radiation failed to induce apoptosis or to decrease expression of non-cleaved caspase-3 and PARP in cell-lines BSC-OF and IS-FOM cells that expressed high levels of HIF-1α. BSC-OF and IS-FOM cells exhibited high migratory capacity. When CoCl 2 was present in the medium, HIF-1α expression increased along with the survival of Ca9-22 cells after radiation exposure. These results suggest that OSCC cells expressing high levels of HIF-1α are resistant to radiation. HIF-1α can be used to control the short term radiosensitivity of cells. (authors)

Intrinsic line shape of electromagnetic radiation from a stack of intrinsic Josephson junctions synchronized by an internal cavity resonance

Science.gov (United States)

Koshelev, Alexei

2013-03-01

Stacks of intrinsic Josephson-junctions are realized in mesas fabricated out of layered superconducting single crystals, such as Bi2Sr2CaCu2O8 (BSCCO). Synchronization of phase oscillations in different junctions can be facilitated by the coupling to the internal cavity mode leading to powerful and coherent electromagnetic radiation in the terahertz frequency range. An important characteristic of this radiation is the shape of the emission line. A finite line width appears due to different noise sources leading to phase diffusion. We investigated the intrinsic line shape caused by the thermal noise for a mesa fabricated on the top of a BSCCO single crystal. In the ideal case of fully synchronized stack the finite line width is coming from two main contributions, the quasiparticle-current noise inside the mesa and the fluctuating radiation in the base crystal. We compute both contributions and conclude that for realistic mesa's parameters the second mechanism typically dominates. The role of the cavity quality factor in the emission line spectrum is clarified. Analytical results were verified by numerical simulations. In real mesa structures part of the stack may not be synchronized and chaotic dynamics of unsynchronized junctions may determine the real line width. Work supported by UChicago Argonne, LLC, under contract No. DE-AC02-06CH11357.

Ionizing radiation effects on the KG1A primitive hematopoietic cell line

International Nuclear Information System (INIS)

Clave, Emmanuel; Carosella, Edgardo D.; Gluckman, Eliane; Dubray, Bernard; Socie, Gerard

1996-01-01

Purpose: Better understanding of radiation-induced effects on the hematopoietic system is important in both the context of therapeutic intervention and accidental exposure. However, direct study of these effects on the hematopoietic stem cell pool is hampered by the small number of accessible cells. We, thus, studied radiation-induced effects on the KG1a stem cell line. Methods and Materials: We confirmed and extended the immunophenotype of KG1a with monoclonal antibodies, established a radiation survival curve, and quantified mRNAs by Northern blotting 30 min after 1, 2, and 3 Gy of ionizing radiation (IR) and followed for up to 48 h after a 3 Gy dose. Cell cycle status and apoptosis were assessed by fluorescent-activated cell sorter (FACS) analysis, cell morphology, and DNA fragmentation. Results: KG1a was found to be CD34+, CD7+, Thy1 low, CD38 low, lineage negative (neg), C-KITneg and HLA-DRneg, a phenotype consistent with a primitive hematopoietic origin. This immunophenotype was not altered by x-ray irradiation. The D 0 value was 1.75 Gy. We showed a time-dependent variation of c-jun mRNA expression with an early and transient dose-dependent induction followed by a second increase at 24 and 48 h: a biphasic dose-dependent variation of bcl-2 expression 30 min after irradiation with a reduction of mRNA level at 1 Gy, and a normalization at higher doses and stable levels of mRNA for c-fos, c-myc, G-CSF, GM-CSF, IL-6, TNF-α, TGF-β, and MIP-1α genes. Cell cycle analysis showed the absence of G1/S phase arrest, a point consistent with the absence of detection of P53 mRNA by Northern blot analysis. The dose-dependent G2/M phase arrest was not followed by significant apoptotic cell death. Conclusion: Taken together, this data indicates that radiation-induced cell death of KG1a, a cell line that has a relatively high D 0 value, does not seem to be the result of the apoptotic pathway but occurs subsequent to a G2/M phase arrest

Dose rate effect models for biological reaction to ionizing radiation in human cell lines

International Nuclear Information System (INIS)

Magae, Junji; Ogata, Hiromitsu

2008-01-01

, suggesting that dose rate effect predicted by MOE model is dependent on DNA repair system. Dose rate effect in a resting normal fibroblast cultured in serum-depleted medium also followed MOE model. In contrast, dose-rate effect was observed in these cell lines deficient of DNA repair system, when they were cultured for more than several month. This dose rate effect did not fit MOE model, and followed a model based on elimination of damaged cells. In conclusion, dose rate effect in growth inhibition and micronucleus formation in cultured cell lines is dependent on dose rate and irradiation time: In higher range of dose rates and short irradiation time, biological effect is determined by dose but not dose rate, and dose rate effect is not observed. In middle range of dose rates and irradiation time, dose rate effect is dependent on DNA repair system, and follows MOE model. In low range of dose-rates and irradiation time longer than several months, dose rate effect is mainly dependent on elimination of damaged cells, and biological effect is determined by dose rate rather than total dose. Our results suggest that dose rate and irradiation time should be included in estimation of long-term radiation risk at low dose rates. (author)

Processing line for industrial radiation-thermal synthesis of doped lithium ferrite powders

Science.gov (United States)

Surzhikov, A. P.; Galtseva, O. V.; Vasendina, E. A.; Vlasov, V. A.; Nikolaev, E. V.

2016-02-01

The paper considers the issues of industrial production of doped lithium ferrite powders by radiation-thermal method. A technological scheme of the processing line is suggested. The radiation-thermal technological scheme enables production of powders with technical characteristics close to the required ones under relatively low temperature annealing conditions without intermediate mixing. The optimal conditions of the radiation-thermal synthesis are achieved isothermally under irradiation by the electron beam with energy of 2.5 MeV in the temperature range of 700-750 0C within- 120 min.

Analytic calculation of radiative-recoil corrections to muonium hyperfine splitting: Electron-line contribution

International Nuclear Information System (INIS)

Eides, M.I.; Karshenboim, S.G.; Shelyuto, V.A.

1991-01-01

The detailed account of analytic calculation of radiative-recoil correction to muonium hyperfine splitting, induced by electron-line radiative insertions, is presented. The consideration is performed in the framework of the effective two-particle formalism. A good deal of attention is paid to the problem of the divergence cancellation and the selection of graphs, relevant to radiative-recoil corrections. The analysis is greatly facilitated by use of the Fried-Yennie gauge for radiative photons. The obtained set of graphs turns out to be gauge-invariant and actual calculations are performed in the Feynman gauge. The main technical tricks, with the help of which we have effectively utilized the existence in the problem of the small parameter-mass ratio and managed to perform all calculations in the analytic form are described. The main intermediate results, as well as the final answer, δE rr = (α(Ζα)/π 2 )(m/M)E F (6ζ(3) + 3π 2 In 2 + π 2 /2 + 17/8), are also presented

SU-E-T-320: The Effect of Survivin Perturbation On the Radiation Response of Breast Cancer Cell Lines

International Nuclear Information System (INIS)

Smith, D; Debeb, B; Woodward, W

2014-01-01

Purpose: Survivin is the smallest member of the inhibitor of apoptosis protein family and is well-known for its universal over-expression in human cancers. Due to its role in apoptosis and cellular proliferation, survivin is implicated in the radiation response in several cancer types, and antisurvivin treatments have had success as a radiation sensitizer in many preclinical cancer models. As no studies to date have reported survivin as a factor affecting radiation resistance in breast cancer models, we sought to evaluate the synergistic relationship between survivin function and irradiation in breast cancer cell lines. Methods: Information regarding survivin protein expression in breast cancer was retrieved from three public databases: Oncomine, Kaplan-Meier Plotter, and GOBO. For the in vitro studies, survivin function was compromised by transducing a non-functional mutant form (survivin-DN) into two breast cancer cell lines, the estrogen receptor-positive MCF7 and the triple-negative, inflammatory SUM149. Cell growth was compared in the survivin-DN and control populations with colony-formation assays. To assess how survivin affects radiation response, clonogenic assays were performed by irradiating the cell lines up to 6 Gy. Results: From the public databases, survivin is more highly expressed in triple-negative breast cancer compared to all other subtypes, and is prognostic of poor survival in all breast cancer patients. In MCF7, the survivin-DN population had decreased colony-formation potential; the opposite was true in SUM149. In the clonogenic assays, abrogation of survivin function radio-protected MCF7 cells in monolayer and 3D growth conditions, while SUM149 survivin-DN cells were radiosensitized in monolayer conditions. Conclusion: We observed synergy between survivin function and radiation, although the results between the two cell lines were disparate. Further investigation is required to identify the mechanism of this discrepancy, including evaluation

Radiation Changes the Metabolic Profiling of Melanoma Cell Line B16.

Directory of Open Access Journals (Sweden)

Lige Wu

Full Text Available Radiation therapy can be an effective way to kill cancer cells using ionizing radiation, but some tumors are resistant to radiation therapy and the underlying mechanism still remains elusive. It is therefore necessary to establish an appropriate working model to study and monitor radiation-mediated cancer therapy. In response to cellular stress, the metabolome is the integrated profiling of changes in all metabolites in cells, which can be used to investigate radiation tolerance mechanisms and identify targets for cancer radiation sensibilization. In this study, using 1H nuclear magnetic resonance for untargeted metabolic profiling in radiation-tolerant mouse melanoma cell line B16, we comprehensively investigated changes in metabolites and metabolic network in B16 cells in response to radiation. Principal component analysis and partial least squares discriminant analysis indicated the difference in cellular metabolites between the untreated cells and X-ray radiated cells. In radiated cells, the content of alanine, glutamate, glycine and choline was increased, while the content of leucine, lactate, creatine and creatine phosphate was decreased. Enrichment analysis of metabolic pathway showed that the changes in metabolites were related to multiple metabolic pathways including the metabolism of glycine, arginine, taurine, glycolysis, and gluconeogenesis. Taken together, with cellular metabolome study followed by bioinformatic analysis to profile specific metabolic pathways in response to radiation, we deepened our understanding of radiation-resistant mechanisms and radiation sensibilization in cancer, which may further provide a theoretical and practical basis for personalized cancer therapy.

Regulation of radiation-induced protein kinase Cδ activation in radiation-induced apoptosis differs between radiosensitive and radioresistant mouse thymic lymphoma cell lines

International Nuclear Information System (INIS)

Nakajima, Tetsuo; Yukawa, Osami; Tsuji, Hideo; Ohyama, Harumi; Wang, Bing; Tatsumi, Kouichi; Hayata, Isamu; Hama-Inaba, Hiroko

2006-01-01

Protein kinase Cδ (PKCδ) has an important role in radiation-induced apoptosis. The expression and function of PKCδ in radiation-induced apoptosis were assessed in a radiation-sensitive mouse thymic lymphoma cell line, 3SBH5, and its radioresistant variant, XR223. Rottlerin, a PKCδ-specific inhibitor, completely abolished radiation-induced apoptosis in 3SBH5. Radiation-induced PKCδ activation correlated with the degradation of PKCδ, indicating that PKCδ activation through degradation is involved in radiation-induced apoptosis in radiosensitive 3SBH5. In radioresistant XR223, radiation-induced PKCδ activation was lower than that in radiosensitive 3SBH5. Cytosol PKCδ levels in 3SBH5 decreased markedly after irradiation, while those in XR223 did not. There was no apparent change after irradiation in the membrane fractions of either cell type. In addition, basal cytosol PKCδ levels in XR223 were higher than those in 3SBH5. These results suggest that the radioresistance in XR223 to radiation-induced apoptosis is due to a difference in the regulation of radiation-induced PKCδ activation compared to that of 3SBH5. On the other hand, Atm -/- mouse thymic lymphoma cells were more radioresistant to radiation-induced apoptosis than wild-type mouse thymic lymphoma cells. Irradiated wild-type cells, but not Atm -/- cells, had decreased PKCδ levels, indicating that the Atm protein is involved in radiation-induced apoptosis through the induction of PKCδ degradation. The decreased Atm protein levels induced by treatment with Atm small interfering RNA had no effect on radiation-induced apoptosis in 3SBH5 cells. These results suggest that the regulation of radiation-induced PKCδ activation, which is distinct from the Atm-mediated cascade, determines radiation sensitivity in radiosensitive 3SBH5 cells

Design and application of radiation apparatus for sup 6 sup 0 Co cargo train on-line inspection system

CERN Document Server

Wu Zhi Fang; Zhang Yuai

2002-01-01

Based on the special requirement for radiation apparatus of sup 6 sup 0 Co cargo train on-line inspection system, a radiation apparatus including two-level shutter, working container, storing container and electromagnetism are designed. The makeup, working mode and functional realization of the radiation apparatus are introduced. The system is used in Manzhouli customs cargo train on-line inspection system. The practice shows that the radiation apparatus is reliable to work steadily and the operating speed of the main shutter can reach 0.1 s open and 0.15 s close

Effects of hematin and Moessbauer gamma-radiation on human osteosarcoma cell lines

International Nuclear Information System (INIS)

Ortalli, I.; Pedrazzi, G.; Fano, V.; Ma, W.; Cai, S.; Giuliani, N.; Passeri, M.

1996-01-01

In the present work it is reported an investigation on cultures of the human osteosarcoma cell line 'MG-63' and the human osteoblastic cell line 'HOBIT'. It is examined the combined effects of hematin and 14,4keV gamma-radiation from a Moessbauer source. Preliminary results seem to confirm the trend already observed for the bone marrow system. Different degrees of growth inhibition were observed when hematin alone and hematin plus gamma-rays were administered to the cultures. It was previously found that hematin has no toxic effects on normal cells up to a concentration of 10 -4 M, but the same concentration produces various degrees of inhibition on cultures of tumor cells. While no significant effect could be attributed to irradiation alone, hematin plus irradiations show a larger inhibition than that expected for pure additive effects

In vitro study of combined cilengitide and radiation treatment in breast cancer cell lines

International Nuclear Information System (INIS)

Lautenschlaeger, Tim; Perry, James; Peereboom, David; Li, Bin; Ibrahim, Ahmed; Huebner, Alexander; Meng, Wei; White, Julia; Chakravarti, Arnab

2013-01-01

Brain metastasis from breast cancer poses a major clinical challenge. Integrins play a role in regulating adhesion, growth, motility, and survival, and have been shown to be critical for metastatic growth in the brain in preclinical models. Cilengitide, an αvβ3/αvβ5 integrin inhibitor, has previously been studied as an anti-cancer drug in various tumor types. Previous studies have shown additive effects of cilengitide and radiation in lung cancer and glioblastoma cell lines. The ability of cilengitide to enhance the effects of radiation was examined preclinically in the setting of breast cancer to assess its possible efficacy in the setting of brain metastasis from breast cancer. Our panel of breast cells was composed of four cell lines: T-47D (ER/PR+, Her2-, luminal A), MCF-7 (ER/PR+, Her2-, luminal A), MDA-MB-231 (TNBC, basal B), MDA-MB-468 (TNBC, basal A). The presence of cilengitide targets, β3 and β5 integrin, was first determined. Cell detachment was determined by cell counting, cell proliferation was determined by MTS proliferation assay, and apoptosis was measured by Annexin V staining and flow cytometry. The efficacy of cilengitide treatment alone was analyzed, followed by assessment of combined cilengitide and radiation treatment. Integrin β3 knockdown was performed, followed by cilengitide and radiation treatment to test for incomplete target inhibition by cilengitide, in high β3 expressing cells. We observed that all cell lines examined expressed both β3 and β5 integrin and that cilengitide was able to induce cell detachment and reduced proliferation in our panel. Annexin V assays revealed that a portion of these effects was due to cilengitide-induced apoptosis. Combined treatment with cilengitide and radiation served to further reduce proliferation compared to either treatment alone. Following β3 integrin knockdown, radiosensitization in combination with cilengitide was observed in a previously non-responsive cell line (MDA-MB-231

Radiation induced expression of survivin in Ewing sarcoma cell-lines

International Nuclear Information System (INIS)

Sheikh-Mounessi, F.; Willich, N.; Greve, B.

2009-01-01

Full text: Introduction: Survivin belongs to the Inhibitor of Apoptosis Protein Family (IAP), is a protein of 16.5 kD and active as a homodimer. It is overexpressed in nearly all human tumors and has a vital function in cell division and apoptotic processes. Beside its role as a relevant prognostic and predictive factor it was described to be a molecular target to improve effectiveness of radiotherapy. We investigated the radiation induced survivin expression in Ewing sarcoma cell-lines. Methods: Ewing sarcoma cells were either irradiated with 10 Gy X-ray and harvested at different time points (0, 2, 4, 6, 10 and 24 h) or irradiated with different doses (0, 2, 5 and 10 Gy) and harvested 24 h later. Protein and mRNA expression was analysed by Westernblot or Real-Time PCR. Results: Directly after irradiation with 10 Gy X-ray survivin mRNA expression was increased in relation to the reference GAPDH. Protein expression was increased in a time dependent manner and reached a maximum after 24h. Three of four investigated cell-lines showed a significant dose dependent increase of survivin protein concentration 24h after irradiation. The same three cell-lines showed a LD50 of >30 Gy. The line with the lowest dose dependent survivin induction was investigated to be most radiosensitive (LD50 = 24 Gy). Discussion: Ewing sarcoma is a childhood tumor with relatively poor prognosis. This tumor often shows significant therapeutic resistance to chemo- and/or radiotherapy. It would be of high interest to find new therapeutic approaches for its treatment. We found a remarkable overexpression of survivin in untreated Ewing sarcoma and a time and dose dependent increase of survivin protein concentration after irradiation with X-ray. The cell-line with the lowest survivin induction showed the highest radiosensitivity. In conclusion, our results show that survivin is an inducible radioresistance factor in Ewing sarcoma. This may open new therapeutic options to treat this aggressive

THE ROLE OF RADIATION PRESSURE IN THE NARROW LINE REGIONS OF SEYFERT HOST GALAXIES

Energy Technology Data Exchange (ETDEWEB)

Davies, Rebecca L.; Dopita, Michael A.; Kewley, Lisa; Groves, Brent; Sutherland, Ralph; Hampton, Elise J.; Banfield, Julie [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Shastri, Prajval; Kharb, Preeti; Bhatt, Harish [Indian Institute of Astrophysics, Sarjapur Road, Bengaluru 560034 (India); Scharwächter, Julia [LERMA, Observatoire de Paris, PSL, CNRS, Sorbonne Universités, UPMC, F-75014 Paris (France); Jin, Chichuan [Max-Planck-Institut für Extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany); Zaw, Ingyin [New York University (Abu Dhabi), 70 Washington Square S, New York, NY 10012 (United States); James, Bethan [Institute of Astronomy, Cambridge University, Madingley Road, Cambridge CB3 0HA (United Kingdom); Juneau, Stéphanie [CEA-Saclay, DSM/IRFU/SAp, F-91191 Gif-sur-Yvette (France); Srivastava, Shweta, E-mail: Rebecca.Davies@anu.edu.au [Astronomy and Astrophysics Division, Physical Research Laboratory, Ahmedabad 380009 (India)

2016-06-10

We investigate the relative significance of radiation pressure and gas pressure in the extended narrow line regions (ENLRs) of four Seyfert galaxies from the integral field Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7). We demonstrate that there exist two distinct types of starburst-active galactic nucleus (AGN) mixing curves on standard emission line diagnostic diagrams, which reflect the balance between gas pressure and radiation pressure in the ENLR. In two of the galaxies the ENLR is radiation pressure dominated throughout and the ionization parameter remains constant (log U ∼ 0). In the other two galaxies radiation pressure is initially important, but gas pressure becomes dominant as the ionization parameter in the ENLR decreases from log U ∼ 0 to −3.2 ≲ log U ≲ −3.4. Where radiation pressure is dominant, the AGN regulates the density of the interstellar medium on kiloparsec scales and may therefore have a direct impact on star formation activity and/or the incidence of outflows in the host galaxy to scales far beyond the zone of influence of the black hole. We find that both radiation pressure dominated and gas pressure dominated ENLRs are dynamically active with evidence for outflows, indicating that radiation pressure may be an important source of AGN feedback even when it is not dominant over the entire ENLR.

Radiation by the numbers: developing an on-line Canadian radiation dose calculator as a public engagement and education tool

Energy Technology Data Exchange (ETDEWEB)

Dalzell, M.T.J. [Sylvia Fedoruk Canadian Centre for Nuclear Innovation, Saskatoon, Saskatchewan (Canada)

2016-06-15

Concerns arising from misunderstandings about radiation are often cited as a main reason for public antipathy towards nuclear development and impede decision-making by governments and individuals. A lack of information about everyday sources of radiation exposure that is accessible, relatable and factual contributes to the problem. As part of its efforts to be a fact-based source of information on nuclear issues, the Sylvia Fedoruk Canadian Centre for Nuclear Innovation has developed an on-line Canadian Radiation Dose Calculator as a tool to provide context about common sources of radiation. This paper discusses the development of the calculator and describes how the Fedoruk Centre is using it and other tools to support public engagement on nuclear topics. (author)

On beam shaping of the field radiated by a line source coupled to finite or infinite photonic crystals.

Science.gov (United States)

Ceccuzzi, Silvio; Jandieri, Vakhtang; Baccarelli, Paolo; Ponti, Cristina; Schettini, Giuseppe

2016-04-01

Comparison of the beam-shaping effect of a field radiated by a line source, when an ideal infinite structure constituted by two photonic crystals and an actual finite one are considered, has been carried out by means of two different methods. The lattice sums technique combined with the generalized reflection matrix method is used to rigorously investigate the radiation from the infinite photonic crystals, whereas radiation from crystals composed of a finite number of rods along the layers is analyzed using the cylindrical-wave approach. A directive radiation is observed with the line source embedded in the structure. With an increased separation distance between the crystals, a significant edge diffraction appears that provides the main radiation mechanism in the finite layout. Suitable absorbers are implemented to reduce the above-mentioned diffraction and the reflections at the boundaries, thus obtaining good agreement between radiation patterns of a localized line source coupled to finite and infinite photonic crystals, when the number of periods of the finite structure is properly chosen.

Design of a synchrotron radiation detector for the test beam lines at the Superconducting Super Collider Laboratory

International Nuclear Information System (INIS)

Hutton, R.D.

1994-01-01

As part of the particle- and momentum-tagging instrumentation required for the test beam lines of the Superconducting Super Collider (SSC), the synchrotron radiation detector (SRD) was designed to provide electron tagging at momentum above 75 GeV. In a parallel effort to the three test beam lines at the SSC, schedule demands required testing and calibration operations to be initiated at Fermilab. Synchrotron radiation detectors also were to be installed in the NM and MW beam lines at Femilab before the test beam lines at the SSC would become operational. The SRD is the last instrument in a series of three used in the SSC test beam fines. It follows a 20-m drift section of beam tube downstream of the last silicon strip detector. A bending dipole just in of the last silicon strip detector produces the synchrotron radiation that is detected in a 50-mm-square cross section NaI crystal. A secondary scintillator made of Bicron BC-400 plastic is used to discriminate whether it is synchrotron radiation or a stray particle that causes the triggering of the NaI crystal's photo multiplier tube (PMT)

Radiative effect of black carbon aerosol on a squall line case in North China

Science.gov (United States)

Fu, Shizuo; Deng, Xin; Li, Zhe; Xue, Huiwen

2017-11-01

The radiative effect of black carbon aerosol (BC) on a squall line case in north China is studied with the Weather Research and Forecasting model. Before the initiation of the squall line, the surface-emitted BC is mixed only in the boundary layer (BL). BC is then transported from the BL into the free troposphere by the updrafts in the squall line system. Once distributed in the atmosphere, BC absorbs solar radiation and heats the surrounding air. The maximum increase of temperature is 0.05 K for the moderately polluted case bc2 and 0.37 K for the heavily polluted case bc20. In case bc2, where the BC concentration is not very high, the solar flux reaching the surface, the sensible heat flux, and the latent heat flux are not significantly affected by BC. In case bc20, the solar flux reaching the surface, the sensible heat flux, and the latent heat flux are reduced by up to 80, 30, and 21 W m- 2, respectively. The reduced surface evaporation leads to a reduced vapor amount at the early stage. After some time, the heating effect causes a large-scale convergence and brings slightly more vapor into the domain. The effect of BC on the cold pool strength and low-level wind shear is small and hence does not significantly affect the triggering of new convections. In addition, our results show that the effect of BC is negligible on the strength and rain rate of the squall line case.

Preparation of oligonucleotide microarray for radiation-associated gene expression detection and its application in lung cancer cell lines

International Nuclear Information System (INIS)

Guo Wanfeng; Lin Ruxian; Huang Jian; Guo Guozhen; Wang Shengqi

2005-01-01

Objective: The response of tumor cell to radiation is accompanied by complex change in patterns of gene expression. It is highly probable that a better understanding of molecular and genetic changes can help to sensitize the radioresistant tumor cells. Methods: Oligonucleotide microarray provides a powerful tool for high-throughput identifying a wider range of genes involved in the radioresistance. Therefore, the authors designed one oligonucleotide microarray according to the biological effect of IR. By using different radiosensitive lung cancer cell lines, the authors identified genes showing altered expression in lung cancer cell lines. To provide independent confirmation of microarray data, semi-quantitative RT-PCR was performed on a selection of genes. Results: In radioresistant A549 cell lines, a total of 18 genes were selected as having significant fold-changes compared to NCI-H446, 8 genes were up-regulated and 10 genes were down-regulated. Subsequently, A549 and NCI-H446 cells were delivered by ionizing radiation. In A549 cell line, we found 22 (19 up-regulated and 3 down-regulated) and 26 (8 up-regulated and 18 down-regulated) differentially expressed genes at 6h and 24h after ionizing radiation. In NCI-H446 cell line, we identified 17 (9 up-regulated and 8 down-regulated) and 18 (6 up-regulated and 12 down-regulated) differentially expressed genes at 6 h and 24 h after ionizing radiation. The authors tested seven genes (MDM2, p53, XRCC5, Bcl-2, PIM2, NFKBIA and Cyclin B1) for RT-PCR, and found that the results were in good agreement with those from the microarray data except for NFKBIA gene, even though the value for each mRNA level might be different between the two measurements. In present study, the authors identified some genes with cell proliferation and anti-apoptosis, such as MdM2, BCL-2, PKCz and PIM2 expression levels increased in A549 cells and decreased in NCI-H446 cells after radiation, and other genes with DNA repair, such as XRCC5, ERCC5

Main line maser emission in the OH ground state Λdoublet as a result of overlapping far infrared transitions

International Nuclear Information System (INIS)

Pelling, M.

1977-01-01

Transitions 2πsub(1/2), j = 5/2, F = 3 → 2πsub(3/2), j = 3/2, F = 2 and 2πsub(1/2), j = 5/2, F = 2 → 2πsub(3/2), J = 3/2, F = 1 have overlapping Doppler line wings at a kinetic temperature of 100 K. This alters the transport of radiation in each line from that which would occur in the absence of line overlap. As a result, the upper levels of the ground state Λ-doublet become overpopulated. (author)

On-line statistical processing of radiation detector pulse trains with time-varying count rates

International Nuclear Information System (INIS)

Apostolopoulos, G.

2008-01-01

Statistical analysis is of primary importance for the correct interpretation of nuclear measurements, due to the inherent random nature of radioactive decay processes. This paper discusses the application of statistical signal processing techniques to the random pulse trains generated by radiation detectors. The aims of the presented algorithms are: (i) continuous, on-line estimation of the underlying time-varying count rate θ(t) and its first-order derivative dθ/dt; (ii) detection of abrupt changes in both of these quantities and estimation of their new value after the change point. Maximum-likelihood techniques, based on the Poisson probability distribution, are employed for the on-line estimation of θ and dθ/dt. Detection of abrupt changes is achieved on the basis of the generalized likelihood ratio statistical test. The properties of the proposed algorithms are evaluated by extensive simulations and possible applications for on-line radiation monitoring are discussed

Fast neutron radiation induced Glu-B1 deficient lines of an elite bread wheat variety

Science.gov (United States)

Five isogenic wheat lines deficient in high-molecular weight subunit (HMW-GS) proteins encoded by the B-genome were identified from a fast-neutron radiation-mutagenized population of Summit, an elite variety of bread wheat (Triticum aestivum L.). The mutant lines differ from the wild-type progenit...

Survey of magnetospheric line radiation events observed by the DEMETER spacecraft

Czech Academy of Sciences Publication Activity Database

Němec, František; Parrot, M.; Santolík, Ondřej; Rodger, C. J.; Rycroft, M. J.; Hayosh, Mykhaylo; Shklyar, D.; Demekhov, A.

2009-01-01

Roč. 114, May 7 (2009), A05203/1-A05203/11 ISSN 0148-0227 Institutional research plan: CEZ:AV0Z30420517 Keywords : Magnetospheric Line Radiation * MLR * DEMETER Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.082, year: 2009 http://onlinelibrary.wiley.com/doi/10.1029/2008JA014016/abstract

The cloud radiative feedback of a midlatitude squall line system and implication for climate study

International Nuclear Information System (INIS)

Chin, H.N.S.

1992-01-01

The main objectives of this study are (1) to study the impact of longwave and shortwave radiation on the thermodynamic and kinematic structure of a midlatitude squall line; and (2) to explore the influence of specifically including the ice phase in the cloud-radiation feedback mechanism for climate models

Radiating properties of solar plasmas

Science.gov (United States)

Bruner, M. E.; Mcwhirter, R. W. P.

1988-01-01

Using a series of 14 previously obtained empirical emission measure distributions and a number of spectral lines observed by the SMM and P78-1 instruments, the total power radiated by a hot plasma is compared to that radiated by individual spectrum lines. Results are presented for different choices of ionization balance and power loss functions. The results indicate that for some lines such as the C IV resonance doublet at 1548 A and 1550 A, the ratio of the line intensity to the total radiated power varied only over a factor of 2, suggesting that well-calibrated measurements of a single line intensity may provide a fairly good estimation of the total radiated power output from the solar plasma.

Radiating properties of solar plasmas

International Nuclear Information System (INIS)

Bruner, M.E.; Mcwhirter, R.W.P.

1988-01-01

Using a series of 14 previously obtained empirical emission measure distributions and a number of spectral lines observed by the SMM and P78-1 instruments, the total power radiated by a hot plasma is compared to that radiated by individual spectrum lines. Results are presented for different choices of ionization balance and power loss functions. The results indicate that for some lines such as the C IV resonance doublet at 1548 A and 1550 A, the ratio of the line intensity to the total radiated power varied only over a factor of 2, suggesting that well-calibrated measurements of a single line intensity may provide a fairly good estimation of the total radiated power output from the solar plasma. 21 references

Radiation-induced apoptosis of chicken lymphocyte B-cell line DT40

International Nuclear Information System (INIS)

Furusawa, Y.; Aoki, M.; Takakura, K.

2003-01-01

Full text: Ionizing radiation causes lesions of DNA, cell cycle arrest, induced cell death, and apoptosis in the irradiated cells. Then it is easy to expect that those events would be increased in a cell line which is defective in DNA repair system. However, induction of apoptosis by irradiation takes so complicated process when the cells are defective of DNA repair system. Indeed by many recent studies it has been clarified that DNA repair gene is also concerned with apoptotic event and some study shows the contrary data. Thus, the relationship between the genetics of apoptosis and that of DNA repair is still unclear. In this study two kinds of DNA repair proteins, Rad54 and Ku70, were focused. Proteins of Rad54 and Ku70 have important role at two type of DNA repair systems called homologous recombination repair and non-homologous end joining repair, respectively. 4 phenotypes of DT40, parent type, ku70-/-, rad54-/- and ku70-/-/rad54-/- were used to study the radiation-induced apoptosis (Previous study shows that survival fraction of 4 phenotypes of DT40 is decreased in the cell line, in which DNA repair gene is defective). From the results in this study, two things are clarifies. One is that the dependence of apoptotic index on phenotypes is so different between at low dose and at high dose irradiation. The other is that Ku70 has effective role to induce apoptosis in DT40 irradiated with high dose X-rays

Signal integrity analysis on discontinuous microstrip line

International Nuclear Information System (INIS)

Qiao, Qingyang; Dai, Yawen; Chen, Zipeng

2013-01-01

In high speed PCB design, microstirp lines were used to control the impedance, however, the discontinuous microstrip line can cause signal integrity problems. In this paper, we use the transmission line theory to study the characteristics of microstrip lines. Research results indicate that the discontinuity such as truncation, gap and size change result in the problems such as radiation, reflection, delay and ground bounce. We change the discontinuities to distributed parameter circuits, analysed the steady-state response and transient response and the phase delay. The transient response cause radiation and voltage jump.

Synchrotron radiation-based quasi-elastic scattering using time-domain interferometry with multi-line gamma rays.

Science.gov (United States)

Saito, Makina; Masuda, Ryo; Yoda, Yoshitaka; Seto, Makoto

2017-10-02

We developed a multi-line time-domain interferometry (TDI) system using 14.4 keV Mössbauer gamma rays with natural energy widths of 4.66 neV from 57 Fe nuclei excited using synchrotron radiation. Electron density fluctuations can be detected at unique lengths ranging from 0.1 nm to a few nm on time scales from several nanoseconds to the sub-microsecond order by quasi-elastic gamma-ray scattering (QGS) experiments using multi-line TDI. In this report, we generalize the established expression for a time spectrum measured using an identical single-line gamma-ray emitter pair to the case of a nonidentical pair of multi-line gamma-ray emitters by considering the finite energy width of the incident synchrotron radiation. The expression obtained illustrates the unique characteristics of multi-line TDI systems, where the finite incident energy width and use of a nonidentical emitter pair produces further information on faster sub-picosecond-scale dynamics in addition to the nanosecond dynamics; this was demonstrated experimentally. A normalized intermediate scattering function was extracted from the spectrum and its relaxation form was determined for a relaxation time of the order of 1 μs, even for relatively large momentum transfer of ~31 nm -1 . The multi-line TDI method produces a microscopic relaxation picture more rapidly and accurately than conventional single-line TDI.

Development of new on line statistical program for the Korean society for radiation oncology

International Nuclear Information System (INIS)

Song, Si Yeol; Ahn, Seung Do; Choi, Eun Kyung; Chung, Weon Kuu; Shin, Kyung Hwan; Cho, Kwan Ho

2015-01-01

To develop new on-line statistical program for the Korean Society for Radiation Oncology (KOSRO) to collect and extract medical data in radiation oncology more efficiently. The statistical program is a web-based program. The directory was placed in a sub-folder of the homepage of KOSRO and its web address is http://www.kosro.or.kr/asda. The operating systems server is Linux and the webserver is the Apache HTTP server. For database (DB) server, MySQL is adopted and dedicated scripting language is the PHP. Each ID and password are controlled independently and all screen pages for data input or analysis are made to be friendly to users. Scroll-down menu is actively used for the convenience of user and the consistence of data analysis. Year of data is one of top categories and main topics include human resource, equipment, clinical statistics, specialized treatment and research achievement. Each topic or category has several subcategorized topics. Real-time on-line report of analysis is produced immediately after entering each data and the administrator is able to monitor status of data input of each hospital. Backup of data as spread sheets can be accessed by the administrator and be used for academic works by any members of the KOSRO. The new on-line statistical program was developed to collect data from nationwide departments of radiation oncology. Intuitive screen and consistent input structure are expected to promote entering data of member hospitals and annual statistics should be a cornerstone of advance in radiation oncology

Development of new on-line statistical program for the Korean Society for Radiation Oncology.

Science.gov (United States)

Song, Si Yeol; Ahn, Seung Do; Chung, Weon Kuu; Shin, Kyung Hwan; Choi, Eun Kyung; Cho, Kwan Ho

2015-06-01

To develop new on-line statistical program for the Korean Society for Radiation Oncology (KOSRO) to collect and extract medical data in radiation oncology more efficiently. The statistical program is a web-based program. The directory was placed in a sub-folder of the homepage of KOSRO and its web address is http://www.kosro.or.kr/asda. The operating systems server is Linux and the webserver is the Apache HTTP server. For database (DB) server, MySQL is adopted and dedicated scripting language is the PHP. Each ID and password are controlled independently and all screen pages for data input or analysis are made to be friendly to users. Scroll-down menu is actively used for the convenience of user and the consistence of data analysis. Year of data is one of top categories and main topics include human resource, equipment, clinical statistics, specialized treatment and research achievement. Each topic or category has several subcategorized topics. Real-time on-line report of analysis is produced immediately after entering each data and the administrator is able to monitor status of data input of each hospital. Backup of data as spread sheets can be accessed by the administrator and be used for academic works by any members of the KOSRO. The new on-line statistical program was developed to collect data from nationwide departments of radiation oncology. Intuitive screen and consistent input structure are expected to promote entering data of member hospitals and annual statistics should be a cornerstone of advance in radiation oncology.

Development of new on line statistical program for the Korean society for radiation oncology

Energy Technology Data Exchange (ETDEWEB)

Song, Si Yeol; Ahn, Seung Do; Choi, Eun Kyung [Dept. of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Chung, Weon Kuu [Dept. of Radiation Oncology, Kyung Hee University Hospital at Kangdong, Kyung Hee University School of Medicine, Seoul (Korea, Republic of); Shin, Kyung Hwan [Dept. of Radiation Oncology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of); Cho, Kwan Ho [Dept. of Radiation Oncology, Proton Therapy Center, National Cancer Center Hospital, Goyang (Korea, Republic of)

2015-06-15

To develop new on-line statistical program for the Korean Society for Radiation Oncology (KOSRO) to collect and extract medical data in radiation oncology more efficiently. The statistical program is a web-based program. The directory was placed in a sub-folder of the homepage of KOSRO and its web address is http://www.kosro.or.kr/asda. The operating systems server is Linux and the webserver is the Apache HTTP server. For database (DB) server, MySQL is adopted and dedicated scripting language is the PHP. Each ID and password are controlled independently and all screen pages for data input or analysis are made to be friendly to users. Scroll-down menu is actively used for the convenience of user and the consistence of data analysis. Year of data is one of top categories and main topics include human resource, equipment, clinical statistics, specialized treatment and research achievement. Each topic or category has several subcategorized topics. Real-time on-line report of analysis is produced immediately after entering each data and the administrator is able to monitor status of data input of each hospital. Backup of data as spread sheets can be accessed by the administrator and be used for academic works by any members of the KOSRO. The new on-line statistical program was developed to collect data from nationwide departments of radiation oncology. Intuitive screen and consistent input structure are expected to promote entering data of member hospitals and annual statistics should be a cornerstone of advance in radiation oncology.

Radiation breeding researches in gamma field. Results of researches

International Nuclear Information System (INIS)

Morishita, Toshikazu

2006-01-01

Abstract of radiation breeding researches and outline of gamma field in IRB (Institute of Radiation Breeding) are described. The gamma field is a circular field of 100 m radius with 88.8TBqCo-60 source at the center. The field is surrounded by a shielding dike of 8 m in height. The effects of gamma irradiation on the growing plants, mutant by gamma radiation and plant molecular biological researches using mutant varieties obtained by the gamma field are explained. For examples, Japanese pear, chrysanthemum, Cytisus, Eustoma grandiflorum, Manila grass, tea and rose are reported. The mutant varieties in the gamma field, nine mutant varieties of flower colors in chrysanthemum, evergreen mutant lines in Manila grass, selection of self-compatible mutants in tea plant, and the plants of the gamma field recently are shown. (S.Y.)

Line radiation of multicharged ions with the Fermi-Dirac level distribution of electrons at high temperatures

International Nuclear Information System (INIS)

Garanin, S.F.

2003-01-01

Line radiation of multicharged ions with the Fermi-Dirac electron distribution by levels in the range of plasma temperatures, when electron movement may be considered quasiclassical, while potential, in which they move, is the Coulomb one, is considered. The spectrum and intensity of ion radiation are calculated. Within high plasma densities the radiation intensity per one ion proved to be independent of density and proportional to T 2 [ru

Characterization of the response of a human breast carcinoma cell line (T-47D) to radiation and chemotherapeutic agents

International Nuclear Information System (INIS)

Prager, A.; Ben-Hur, E.; Riklis, E.

1981-01-01

The response of a human breast carcinoma cell line (T-47D) to various antitumour agents, gamma irradiation, UV light and heat was studied, using the colony-forming ability technique. Combinations of radiation with drugs and heat were also tested. The resulting survival curves corresponded to one of five patterns: simple exponential, biphasic exponential, threshold exponential, exponential plateau and ineffectual. Whereas the cells were particularly sensitive to gamma irradiation, the response to UV light was normal. The patient from whom this cell line originated did not respond to METHOTREXATEsup(R) therapy. The in vitro results correlated with this observation. (author)

Enhancement of radiation cytotoxicity by gold nanoparticles in MCF-7 breast cancer cell lines

Energy Technology Data Exchange (ETDEWEB)

Rosli, Nur Shafawati binti; Rahman, Azhar Abdul [School of Physics, Universiti Sains Malaysia, 11800, Pulau Pinang (Malaysia); Aziz, Azlan Abdul [School of Physics, Universiti Sains Malaysia, 11800, Pulau Pinang (Malaysia); Nano-Biotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800, Pulau Pinang (Malaysia); Shamsuddin, Shaharum [Nano-Biotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800, Pulau Pinang (Malaysia); School of Health Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia)

2015-04-24

Therapy combined with metallic nanoparticles is a new way to treat cancer, in which gold nanoparticles (AuNPs) are injected through intravenous administration and bound to tumor sites. Radiotherapy aims to deliver a high therapeutic dose of ionizing radiation to the tumor without exceeding normal tissue tolerance. The use of AuNPs which is a high-atomic-number (Z) material in radiotherapy will provide a high probability for photon interaction by photoelectric effect. These provide advantages in terms of radiation dose enhancement. The high linear energy transfer and short range of photoelectric interaction products (photoelectrons, characteristic x-rays, Auger electrons) produce localized dose enhancement of the tumor. In this work, breast cancer cell lines (MCF-7) are seeded in the 96-well plate and were treated with 13 nm AuNPs before they were irradiated with 6 MV and 10 MV photon beam from a medical linear accelerator at various radiation doses. To validate the enhanced killing effect, both with and without AuNPs MCF-7 cells is irradiated simultaneously. By comparison, the results show that AuNPs significantly enhance cancer killing.

In vitro radiation and chemotherapy sensitivity of established cell lines of human small cell lung cancer and its large cell morphological variants

International Nuclear Information System (INIS)

Carney, D.N.; Mitchell, J.B.; Kinsella, T.J.

1983-01-01

The in vitro response to radiation and chemotherapeutic drugs of cell lines established from 7 patients with small cell (SC) lung cancer were tested using a soft agarose clonogenic assay. Five cell lines retained the typical morphological and biochemical amine precursor uptake decarboxylation characteristics of SC, while two cell lines had undergone ''transformation'' to large cell (LC) morphological variants with loss of amine precursor uptake decarboxylation cell characteristics of SC. The radiation survival curves for the SC lines were characterized by D0 values ranging from 51 to 140 rads and extrapolation values (n) ranging from 1.0 to 3.3. While the D0 values of the radiation survival curves of the LC variants were similar (91 and 80 rads), the extrapolation values were 5.6 and 11.1 In vitro chemosensitivity testing of the cell lines revealed an excellent correlation between prior treatment status of the patient and in vitro sensitivity or resistance. No correlation was observed between in vitro chemosensitivity and radiation response. These data suggest that transformation of SC to LC with loss of amine precursor uptake and decarboxylation characteristics is associated with a marked increase in radiation resistance (n) in vitro. The observation of a 2- to 5-fold increase in survival of the LC compared to the SC lines following 200 rads suggests that the use of larger daily radiation fractions and/or radiation-sensitizing drugs might lead to a significantly greater clinical response in patients with LC morphology. This clinical approach may have a major impact on patient response and survival

RADIATIVE TRANSFER MODELING OF THE ENIGMATIC SCATTERING POLARIZATION IN THE SOLAR Na i D{sub 1} LINE

Energy Technology Data Exchange (ETDEWEB)

Belluzzi, Luca [Istituto Ricerche Solari Locarno, CH-6605 Locarno Monti (Switzerland); Bueno, Javier Trujillo [Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife (Spain); Degl’Innocenti, Egidio Landi [Dipartimento di Fisica e Astronomia, Università di Firenze, I-50125 Firenze (Italy)

2015-12-01

The modeling of the peculiar scattering polarization signals observed in some diagnostically important solar resonance lines requires the consideration of the detailed spectral structure of the incident radiation field as well as the possibility of ground level polarization, along with the atom's hyperfine structure and quantum interference between hyperfine F-levels pertaining either to the same fine structure J-level, or to different J-levels of the same term. Here we present a theoretical and numerical approach suitable for solving this complex non-LTE radiative transfer problem. This approach is based on the density-matrix metalevel theory (where each level is viewed as a continuous distribution of sublevels) and on accurate formal solvers of the transfer equations and efficient iterative methods. We show an application to the D-lines of Na i, with emphasis on the enigmatic D{sub 1} line, pointing out the observable signatures of the various physical mechanisms considered. We demonstrate that the linear polarization observed in the core of the D{sub 1} line may be explained by the effect that one gets when the detailed spectral structure of the anisotropic radiation responsible for the optical pumping is taken into account. This physical ingredient is capable of introducing significant scattering polarization in the core of the Na i D{sub 1} line without the need for ground-level polarization.

Application of the inter-line PCR for the analyse of genomic rearrangements in radiation-transformed mammalian cell lines; Anwendung der Inter-Line PCR zur Analyse von genomischen Veraenderungen in strahlentransformierten Saeugerzellinien

Energy Technology Data Exchange (ETDEWEB)

Leibhard, S.; Smida, J. [Muenchen Univ. (Germany). Strahlenbiologisches Inst.; Eckardt-Schupp, F.; Hieber, L. [GSF-Inst. fuer Strahlenbiologie, Oberschleissheim (Germany)

1996-12-31

Repetitive DNA sequences of the LINE-family (long interspersed elements) that are widely distributed among the mammalian genome can be activated or altered by the exposure to ionizing radiation [1]. By the integration at new sites in the genome alterations in the expression of genes that are involved in cell transformation and/or carcinogenesis may occur [2, 3]. A new technique - the inter-LINE PCR - has been developed in order to detect and analyse such genomic rearrangements in radiation-transformed cell lines. From the sites of transformation- or tumour-specific changes in the genome it might be possible to develop new tumour markers for diagnostic purpose. (orig.) [Deutsch] Repetitive DNA-Sequenzen der LINE-Familie, die weit verbreitet im Genom von Saeugerzellen vorkommen, koennen durch Exposition mit ionisierender Strahlung aktiviert und veraendert werden [1]. Durch eine Neu- bzw. Reintegration an anderen Positionen im Genom kann es zu bedeutenden Veraenderungen im Genom der Zelle kommen. Die Expression von Genen, die bei den Prozessen der Zelltransformation bzw. der Karzinogenese beteiligt sind, kann dadurch veraendert werden [2, 3]. Mithilfe der von uns entwickelten Inter-LINE PCR und der anschliessenden Analyse der veraenderten Produktmuster nach gelelektrophoretischer Auftrennung koennen solche `genomic rearrangements` unter Beteiligung von LINE-Elementen untersucht und naeher charakterisiert werden. Durch Klonierung und Sequenzierung transformations- bzw. tumorspezifischer PCR-Produkte sollte es moeglich sein Tumormarker fuer diagnostische Zwecke zu entwickeln. Die Methode wurde fuer die Analyse von Zellen des Syrischen Hamster aufgebaut, sie ist jedoch universell fuer alle Saeuger anwendbar. (orig.)

Relationship between radiation induced activation of DNA repair genes and radiation induced apoptosis in human cell line A431

International Nuclear Information System (INIS)

Bom, Hee Seung; Min, Jung Jun; Kim, Kyung Keun; Choi, Keun Hee

2000-01-01

The purpose of this study was to evaluate the relationship between radiation-induced acivation of DNA repair genes and radiation induced apoptosis in A431 cell line. Five and 25 Gys of gamma radiation were given to A431 cells by a Cs-137 cell irradiator. Apoptosis was evaluated by flow cytometry using annexin V-fluorescein isothiocyanate and propidium iodide staining. The expression of DNA repair genes was evaluated by both Northern and Western blot analyses. The number of apoptotic cells increased with the increased radiation dose. It increased most significantly at 12 hours after irradiation. Expression of p53, p21, and ℎRAD50 reached the highest level at 12 hours after 5 Gy irradiation. In response to 25 Gy irradiation, ℎRAD50 and p21 were expressed maximally at 12 hours, but p53 and GADD45 genes showed the highest expression level after 12 hours. Induction of apoptosis and DNA repair by ionizing radiation were closely correlated. The peak time of inducing apoptosis and DNA repair was 12 hours in this study model. ℎRAD50, a recently discovered DNA repair gene, was also associated with radiation-induced apoptosis.=20

Integration of on-line imaging, plan adaptation and radiation delivery: proof of concept using digital tomosynthesis

International Nuclear Information System (INIS)

Mestrovic, Ante; Otto, Karl; Nichol, Alan; Clark, Brenda G

2009-01-01

The main objective of this manuscript is to propose a new approach to on-line adaptive radiation therapy (ART) in which daily image acquisition, plan adaptation and radiation delivery are integrated together and performed concurrently. A method is described in which on-line ART is performed based on intra-fractional digital tomosynthesis (DTS) images. Intra-fractional DTS images were reconstructed as the gantry rotated between treatment positions. An edge detection algorithm was used to automatically segment the DTS images as the gantry arrived at each treatment position. At each treatment position, radiation was delivered based on the treatment plan re-optimized for the most recent DTS image contours. To investigate the feasibility of this method, a model representing a typical prostate, bladder and rectum was used. To simulate prostate deformations, three clinically relevant, non-rigid deformations (small, medium and large) were modeled by systematically deforming the original anatomy. Using our approach to on-line ART, the original treatment plan was successfully adapted to arrive at a clinically acceptable plan for all three non-rigid deformations. In conclusion, we have proposed a new approach to on-line ART in which plan adaptation is performed based on intra-fractional DTS images. The study findings indicate that this approach can be used to re-optimize the original treatment plan to account for non-rigid anatomical deformations. The advantages of this approach are 1) image acquisition and radiation delivery are integrated in a single gantry rotation around the patient, reducing the treatment time, and 2) intra-fractional DTS images can be used to detect and correct for patient motion prior to the delivery of each beam (intra-fractional patient motion).

Study of the cell cycle control for human malignant mesothelioma lines. Interferon and radiations effect

International Nuclear Information System (INIS)

Vivo, C.

1999-01-01

In order to better understand the inhibition mechanisms of the IFN-R-HU on tumoral development, the IFN-R-U effect on MM lines has been studied. Three groups of lines has been distinguished: eight sensitive lines, two intermediate and three resistant. The sensitive lines showed a triple locking of the cell cycle: in phases S, G1 and G2. The study of the cell cycle control points function, realized by the MM lines radiation exposure showed the points function on G1/S and-or on G2/M and the dependence or non dependence of the cycle stop of the protein P53 and P21 W at F1/CIP1. (A.L.B.)

The combined effect of fludarabine monophosphate and radiation on lymphatic cell lines in vitro

Energy Technology Data Exchange (ETDEWEB)

Nitsche, M.; Rave-Fraenk, M.; Wolter, C.; Hess, C.F. [Gottingen Univ. Georg-August, Dept. of Radiation Oncology (Germany); Pradier, O. [Centre Hospitalier Universitaire, Dept. de Cancerologie, 29 - Brest (France)

2006-11-15

We could demonstrate a fludarabine-induced radiosensitization in two of four cell lines tested. We conclude, that fludarabine may play a role as radiosensitizer. The combined effect of low dose fludarabine and low dose radiation emphasizes the idea of possible multiple reapplication of radio chemotherapy in progressive lymphoma. Further investigations are warranted to identify the potential of this drug as a radiosensitizer in vivo and to elucidate the mechanism of interaction of the drug and radiation. (N.C.)

Modeling of the He-like magnesium spectral lines radiation from the plasma created by XeCl and Nd-glass lasers

International Nuclear Information System (INIS)

Stepanov, A. E.; Starostin, A. N.; Roerich, V. C.; Makhrov, V. A.; Faenov, A. Ya.; Magunov, A. I.; Pikuz, T. A.; Skobelev, I. Yu.; Flora, F.; Bollanti, S.; Di Lazzaro, P.; Lisi, N.; Letardi, T.; Palladino, L.; Reale, A.; Batani, D.; Bossi, S.; Bornadinelo, A.; Scafati, A.; Reale, L.

1997-01-01

Resonant and intercombination spectral lines formation of He-like magnesium is analyzed both experimentally and numerically. It is shown that in plasma created by XeCl laser at flux density 8·10 12 W/cm 2 the peak of electron temperature is placed downstream from the critical surface at density significantly smaller than critical, and radiation in both resonant and recombination lines is also produced by the plasma region with density below critical. Simulations also show significant line radiation at large distances (1-2 mm) from the target as it was observed in experiments. This secondary peak is produced by a compression wave forming near the plasma front. As opposite, radiation in these lines in plasma created by Nd-glass laser at flux density 5·10 13 W/cm 2 comes from the plasma region placed deeper than the critical surface and has no tail at large distances

Determination of gamma radiation lethal dose (LD50) and resveratrol cytotoxicity level in tumor cells line

International Nuclear Information System (INIS)

Magalhaes, Vanessa D.; Rogero, Sizue O.; Rogero, Jose R.; Cruz, Aurea S.

2011-01-01

Cancer is a disease with high incidence and it is considered a worldwide public health problem. Resveratrol is a polyphenol occurring naturally in a wide variety of plants according to response of ultraviolet radiation (UV) exposition or according to mechanical stress resulting of pathogens or chemical and physical agents. This polyphenol possesses a pharmacological activity of carcinogenesis inhibition in multiple levels. It also protects cells by scavenging the free radicals which are considered toxic products. These free radicals are formed of natural process of cell aging and also by incidence of ionizing radiation in the organism. Thus, resveratrol is considered as a cell radioprotector. On the other hand, in some elevated concentrations resveratrol may be considered as a radiosensitizing. The aim of this work was the determination of radiation lethal dose (LD 50 ) and also verifies the cytotoxicity level of resveratrol in tumor cells line: muco epidermoid pulmonary carcinoma cells (NCI-H292) and rhabdomyosarcoma cells (RD). The cytotoxicity test was performed by neutral red uptake assay. The results of resveratrol IC 50% in NCI-H292 cells was 192μM and in RD cells was 128μM; and RD cells gamma radiation LD 50 was 435Gy. (author)

Establishment of immortalized B lymphoblastoid cell lines of old residents in high background radiation area in Guangdong, China

International Nuclear Information System (INIS)

Lu Xue; Feng Jiangbing; Chen Deqing; Liu Qingjie; Cha Yongru; Zou Jianming

2008-01-01

Objective: To establish the immortalized cell lines of peripheral blood lymphocytes for old male residents in high background radiation area (HBRA) in Guangdong, China, in order to preserve the specific genomic resources of residents in HBRA for the further genetic and molecular biological study on HBRA. Methods: The peripheral blood samples of 20 old male residents in HBRA were collected after informed consent. The immortalized B lymphoblastoid cell lines, 2 fox each resident, were established with Epstein-Barr virus. After being frozen and recovered, the cell viability, the contamination of bacterium and mycoplasma were analyzed. The stabilization of cell lines was decided by comparing the karyotypes of the peripheral blood lymphocytes and the cell lines. Results: 40 cell lines for 20 residents in HBRA were successfully established.. The recovery rate of cell lines after being frozen was 100% . All the cell viablity after recovery was higher than 90%, and no contamination of bacteria and mycoplasma occurred. The karyotypes of the 20th generation cell lines were not change. Conclusion: The immortalized cell lines established in this study could provide biological resources for further study on genetics and molecular biology in HBRA. (authors)

The integrin α6β4 as a signaling membrane protein for a damage response to ionizing radiation in human prostate cancer cell lines

International Nuclear Information System (INIS)

Woo, Charles; Nagle, Ray B.; Stea, Baldassarre; Cress, Anne E.

1996-01-01

Purpose/Object: Integrins are cell surface receptors that exist as heterodimers. The integrin α6β4 is a receptor for laminin and is present in normal human prostate tissue. In prostate carcinoma however, there is loss of β4 expression. Prior studies demonstrated that when a low β4 expressing rectal carcinoma cell line was transfected with β4, the cells underwent apoptosis. We investigated the effects that the β4 integrin had on DNA damage responses in a human prostate carcinoma line. Materials and Methods: DU-145 human prostate carcinoma cells previously selected by us for α6β1 expression were transfected with either a full length β4 construct or vector only. Both cell lines were grown simultaneously and maintained in geneticin for selection purposes. Cells were grown on glass coverslips in 60mm tissue culture dishes under optimal growth conditions. Radiation was delivered using a Co-60 machine with a dose rate of 35 Gy/hr. The cells were given 0, 2, 5, and 10 Gy. Three different radiation damage responses were assayed and include micronuclei (MN) formation, cell cycle distribution, and cell survival. 24 hours after irradiation, the cells were fixed and stained with propidium iodide. Micronuclei formation was detected using a Zeiss LSM10 confocal microscope, and the resulting digital images were analyzed using the NIH Image program. The observed MN were detected without the use of cytochalasin B, but were noted to contain nuclear histone and DNA and were morphologically distinct from apoptotic or necrotic bodies. Results: The quantitative analysis of MN formation revealed a radiation dose dependence of MN formation in both the α6β4 and α6β1 expressing cell lines. The presence of MN 24 hours after irradiation was observed at clinically significant doses (2 Gy) with the largest effect occurring at 5 Gy. The α6β4 expressing cells consistently produced approximately two fold more MN as compared to the α6β1 expressing cells at all radiation doses. The

Development of a Handheld Line Information Reader and Generator for Efficient Management of Optical Communication Lines.

Science.gov (United States)

Lee, Jaeyul; Kwon, Hyungwoo; Song, Jaewon; Jeon, Mansik; Kim, Jeehyun

2017-08-24

A handheld line information reader and a line information generator were developed for the efficient management of optical communication lines. The line information reader consists of a photo diode, trans-impedance amplifier, voltage amplifier, microcontroller unit, display panel, and communication modules. The line information generator consists of a laser diode, laser driving circuits, microcontroller unit, and communication modules. The line information reader can detect the optical radiation field of the test line by bending the optical fiber. To enhance the sensitivity of the line information reader, an additional lens was used with a focal length of 4.51 mm. Moreover, the simulation results obtained through BeamPROP ® software from Synopsys, Inc. demonstrated a stronger optical radiation field of the fiber due to a longer transmission wavelength and larger bending angle of the fiber. Therefore, the developed devices can be considered as useful tools for the efficient management of optical communication lines.

Recent results on CVD diamond radiation sensors

Science.gov (United States)

Weilhammer, P.; Adam, W.; Bauer, C.; Berdermann, E.; Bogani, F.; Borchi, E.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; v. d. Eijk, R.; van Eijk, B.; Fallou, A.; Fish, D.; Fried, M.; Gan, K. K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Knopfle, K. T.; Krammer, M.; Manfredi, P. F.; Meier, D.; LeNormand; Pan, L. S.; Pernegger, H.; Pernicka, M.; Plano, R.; Re, V.; Riester, J. L.; Roe, S.; Roff; Rudge, A.; Schieber, M.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Tapper, R. J.; Tesarek, R.; Thomson, G. B.; Trawick, M.; Trischuk, W.; Turchetta, R.; RD 42 Collaboration

1998-02-01

CVD diamond radiation sensors are being developed for possible use in trackers in the LHC experiments. The diamond promises to be radiation hard well beyond particle fluences that can be tolerated by Si sensors. Recent results from the RD 42 collaboration on charge collection distance and on radiation hardness of CVD diamond samples will be reported. Measurements with diamond tracking devices, both strip detectors and pixel detectors, will be discussed. Results from beam tests using a diamond strip detector which was read out with fast, 25 ns shaping time, radiation-hard pipeline electronics will be presented.

Mutant p53 transfection of astrocytic cells results in altered cell cycle control, radiation sensitivity, and tumorigenicity

International Nuclear Information System (INIS)

Kanady, Kirk E.; Mei Su; Proulx, Gary; Malkin, David M.; Pardo, Francisco S.

1995-01-01

Introduction: Alterations in the p53 tumor suppressor gene are one of the most frequent genetic alterations in malignant gliomas. An understanding of the molecular genetic events leading to glial tumor progression would aid in designing therapeutic vectors for controlling these challenging tumor types. We investigated whether mutations in coding exons of the p53 gene result in functional changes altering cell cycle 'checkpoint' control and the intrinsic radiation sensitivity of glial cells. Methods: An astrocytic cell line was derived from a low grade astrocytoma and characterized to be of human karyotype and GFAP positivity. Additionally, the cellular population has never formed tumors in immune-deficient mice. At early passage ( 2 as parameters. Cell kinetic analyses after 2, 5, and 10 Gy of ionizing radiation were conducted using propidium iodide FACS analyses. Results: Overall levels of p53 expression were increased 5-10 fold in the transfected cellular populations. Astrocytic cellular populations transfected with mutant p53 revealed a statistically significant increase in levels of resistance to ionizing radiation in vitro (2-tailed test, SF2, MID). Astrocytic cellular populations transfected with mutant p53, unlike the parental cells, were tumorigenic in SCID mice. Cell kinetic analyses indicated that the untransfected cell line demonstrated dose dependent G1 and G2 arrests. Following transfection, however, the resultant cellular population demonstrated a predominant G2 arrest. Conclusions: Astrocytic cellular populations derived from low grade astrocytomas, are relatively radiation sensitive, non-tumorigenic, and have intact cell cycle ''checkpoints.'' Cellular populations resulting upon transfection of parental cells with a dominant negative p53 mutation, are relatively radiation resistant, when compared to both parental and mock-transfected cells. Transfected cells demonstrate abnormalities of cell cycle control at the G1/S checkpoint, increases in levels

Trichostatin A, a histone deacetylase inhibitor, potentiated cytotoxic effect of lionizing radiation in human head and neck cancer cell lines

International Nuclear Information System (INIS)

Kim, Jin Ho; Shin, Jin Hee; Chie, Eui Kyu; Wu, Hong Gyun; Kim, Jae Sung; Kim, Il Han; Ha, Sung Whan; Park, Charn Il; Kang, Wee Saing

2004-01-01

We have previously reported that human glioblastoma cells are sensitized to radiation-induced death after their exposure to trichostatin A (TSA), a histone deacetylase inhibitor (HDAC-I), prior to the irradiation. We aimed to measure the magnitude of the radiosensitizing effect of TSA in human head and neck cancer cell lines. human head and neck cancer cell lines, HN-3 and HN-9, were exposed to 0, 50, 100, and 200 nM TSA for 18 hr prior to irradiation. Then, the TSA-treated cells were irradiated with 0, 2, 4, 6, and 8 Gy, and cell survival was measured by clonogenic assay. Pre-irradiation exposure to TSA was found to radiosensitize HN-3 and HN-9 cell lines. In HN-9 cells, the fraction surviving after 2 Gy (SF2) was significantly reduced by treatment of TSA at concentration as low as 50 nM. However, a treatment with 200 nM TSA was required to significantly decrease SF2 in the HN-3 cell line. SER of pre-irradiation treatment with 200 nM TSA was 1.84 in HN-3 and 7.24 in HN-9, respectively. Our results clearly showed that human head and neck cancer cell lines can be sensitized to ionizing radiation by pre-irradiation inhibition of histone deacetylase (HDAC) using TSA, and that this potentiation might well be a general phenomenon

On-Line Radiation Test Facility for Industrial Equipment needed for the Large Hadron Collider at CERN

CERN Document Server

Rausch, R

1999-01-01

The future Large Hadron Collider to be built at CERN will use superconducting magnets cooled down to 1.2 K. To preserve the superconductivity, the energy deposition dose levels in equipment located outside the cryostat, in the LHC tunnel, are calculated to be of the order of 1 to 10 Gy per year. At such dose levels, no major radiation-damage problems are to be expected, and the possibility of installing Commercial Of The Shelf (COTS) electronic equipment in the LHC tunnel along the accelerator is considered. To this purpose, industrial electronic equipment and circuits have to be qualified and tested against radiation to insure their long term stability and reliability. An on-line radiation test facility has been setup at the CERN Super Proton Synchrotron (SPS) and a program of on-line tests for electronic equipment is ongoing. Equipment tested includes Industrial Programmable Logic Controllers (PLCs) from several manufacturers, standard VME modules, Fieldbuses like Profibus, WorldFIP and CAN, various electro...

Detailed properties of magnetospheric line radiation events observed by the DEMETER spacecraft

Czech Academy of Sciences Publication Activity Database

Němec, F.; Parrot, M.; Santolík, Ondřej

2012-01-01

Roč. 117, A5 (2012), A05210/1-A05210/9 ISSN 0148-0227 R&D Projects: GA ČR GA205/09/1253; GA MŠk ME09107 Institutional support: RVO:68378289 Keywords : magnetospheric line radiation * electromagnetic waves Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.174, year: 2012 http://onlinelibrary.wiley.com/doi/10.1029/2012JA017517/abstract

On-line monitoring of base current and forward emitter current gain of the voltage regulator's serial pnp transistor in a radiation environment

Directory of Open Access Journals (Sweden)

Vukić Vladimir Đ.

2012-01-01

Full Text Available A method of on-line monitoring of the low-dropout voltage regulator's operation in a radiation environment is developed in this paper. The method had to enable detection of the circuit's degradation during exploitation, without terminating its operation in an ionizing radiation field. Moreover, it had to enable automatic measurement and data collection, as well as the detection of any considerable degradation, well before the monitored voltage regulator's malfunction. The principal parameters of the voltage regulator's operation that were monitored were the serial pnp transistor's base current and the forward emitter current gain. These parameters were procured indirectly, from the data on the voltage regulator's load and quiescent currents. Since the internal consumption current in moderately and heavily loaded devices was used, the quiescent current of a negligibly loaded voltage regulator of the same type served as a reference. Results acquired by on-line monitoring demonstrated marked agreement with the results acquired from examinations of the voltage regulator's maximum output current and minimum dropout voltage in a radiation environment. The results were particularly consistent in tests with heavily loaded devices. Results obtained for moderately loaded voltage regulators and the risks accompanying the application of the presented method, were also analyzed.

Measurements of national radiation exposure rates on train lines in Tokai area

International Nuclear Information System (INIS)

Matsuda, Hideharu

1996-01-01

For data accumulation of natural radiation exposure rate derived from gamma-ray and cosmic-ray to evaluate population dose, the author measured the rate in the running vehicles of 12 JR Tokai lines, 17 Nagoya Railway lines, 4 Kinkinippon Railway lines and 1 line of Nagoya City Bus. A portable gamma spectrometer equipped with 3' in diameter x 3' NaI (Tl) scintillation detector was placed on the seat of the vehicle for measurement in the period of December, 1992-August, 1995. Gamma-ray and cosmic-ray exposure rates in air were assessed separately as reported before and expressed in Gy/h. The average exposure rate of gamma-ray in JR Tokai lines was 19.8 nGy/h and of cosmic-ray, 28.5 nGy/h, both of which were markedly varied from line to line. The average rates of gamma-and cosmic-ray were 21.6 nGy/h and 29.0 nGy/h, respectively, in Nagoya Railway lines and 20.9 nGy/h and 28.7 nGy/h, respectively, in Kinkinippon lines. In the city bus, the respective rates were 27.2 nGy/h and 27.0 nGy/h. Thus, the average rates of gamma-ray (about 20 nGy/h) and cosmic-ray (about 29 nGy/h) were not so different between JR and other private railway lines. In the bus, the former rate was slightly lower and the latter, slightly higher. However, the total rates of both rays were in the range of about 50-55 nGy/h in all vehicles examined. (H.O.)

A New Radio Spectral Line Survey of Planetary Nebulae: Exploring Radiatively-driven Heating and Chemistry of Molecular Gas

Science.gov (United States)

Bublitz, Jesse; Kastner, Joel H.; Santander-García, Miguel; Montez, Rodolfo; Alcolea, Javier; Balick, Bruce; Bujarrabal, Valentín

2018-01-01

We report the results of a survey of mm-wave molecular line emission from nine nearby (Radioastronomie Millimétrique (IRAM) 30 m telescope. Our sample comprises molecule-rich PNe spanning a wide range of central star UV luminosities as well as central star and nebular X-ray emission properties. Nine molecular line frequencies were chosen to investigate the molecular chemistry of these nebulae. New detections of one or more of five molecules -- the molecular mass tracer 13CO and the chemically important trace species HCO+, CN, HCN, and HNC -- were made in at least one PN. We present analysis of emission line flux ratios that are potential diagnostics of the influence that ultraviolet and X-ray radiation have on the chemistry of residual molecular gas in PNe.

Enhancement of Temozolomide and radiation induced damage in malignant glioma cell lines by 2-deoxy-D-glucose

International Nuclear Information System (INIS)

Kumari, Kalyani; Shyam, Sai; Chandrasekhar Sagar, B.K.; Jagath Lal, G.; Kalia, Vijay Kumar

2014-01-01

Malignant Gliomas are the most common and aggressive CNS tumors. The current standard treatment includes surgery, followed by Temozolomide (TMZ)-Radiotherapy. It leads to increased survival as compared to radiotherapy alone. However hematological toxicities are also increased by the combination treatments. Therefore, it is important to carry out further preclinical studies, to develop more effective treatment for these tumors. 2-deoxy-D-Glucose (2-DG), an inhibitor of glycolytic energy metabolism, has been shown earlier to differentially inhibit growth and survival of tumor cells in vitro. It also increases tumor regression in experimental models; and has been used in a few clinical studies as radiosensitizer. In the present study, effects of combining 2-DG with TMZ on radiation induced damage were studied in established malignant glioma cell lines (U251MG and U87MG); and primary cultures derived from malignant glioma biopsies. Exponentially growing cells were exposed to drugs and radiation. Drugs were removed 4 hours later and cultures were processed further for different assays of damage. Effects on proliferation response, viability and total cellular damage (TCD; micronuclei + apoptosis) were studied after post-treatment growth for 1, 2, 4 or 6 days. Our results showed that combination of 2-DG with TMZ ± Radiation significantly inhibited tumor cell proliferation up to 6 days, at low drug concentrations in primary as well as in established cell lines. The TCD at 24 and 48 hours after Gamma irradiation was also significantly increased by the combination of drugs as compared to individual treatments. Experiments to study proliferation kinetics by flow cytometry and cell survival are in progress. These studies suggest that 2-DG significantly enhances the cytotoxic effect of TMZ + radiation without increasing toxic side effects. Therefore, combining 2-DG with TMZ+ radiation therapy could be a potential strategy to improve the therapeutic outcome for Malignant

The anti-epidermal growth factor receptor (EGFR) monoclonal antibody, C225, enhances radiation-induced apoptosis in primary glioma cell lines through mediation of MAPK/JNK/p38 signaling pathways

International Nuclear Information System (INIS)

Chakravarti, A.; Noll, E.; Black, P.M.; Loeffler, J.S.

2001-01-01

Purpose: Increasing evidence suggests that signaling mediated by the epidermal growth factor receptor (EGFR) pathway contributes to radiation resistance. The anti-EGFR monoclonal antibody, C225, has been shown to enhance radiation response for several tumor types in preclinical models. Malignant gliomas are known to express, and quite frequently overexpress, EGFR. Our objectives in this study were to 1) Evaluate the efficacy of C225 as a radiation response modifier in EGFR-expressing glioma cell lines and to 2) Investigate the underlying molecular mechanisms mediating C225-induced enhancement of radiation response. Materials and Methods: Twelve EGFR-expressing glioma cells lines, established from patient tumors, were used for this study. Cells were incubated with C225, irradiated, and then evaluated for radiation response. Assays used to evaluate efficacy of C225-mediated radiosensitization included time-course apoptosis assays (Annexin V and TUNEL), viability assays (MTT), and clonogenic survival assays. The changes along MAPK (p44/p42)/JNK/p38-MAPK signal transduction pathways were then investigated using quantitative Western analysis with phospho-specific antibodies to determine the molecular mechanisms by which C225 mediates a given response. Results: C225 clearly enhanced radiation response for 7 of the 12 primary glioma cell lines studied. Enhancement of both immediate and delayed apoptotic responses was evident in these 7 responsive cell lines after C225 administration. The average apoptosis index at 6 hours post-RT+C225 for the 7 responsive lines was 9.5%, compared to 1.2% for the RT-only controls. A pattern of delayed apoptosis was evident in these 7 lines, with secondary apoptotic peaks (∼ 8.0%) occurring at 24 hours post-RT+C225. Time course viability measurements revealed a steady decrease in viable tumor cells in these responsive cell lines from 75% at 6 hours post-RT+C225 to 20% at 7 days. Clonogenic survival was also diminished in these 7 lines

Failed Radiatively Accelerated Dusty Outflow Model of the Broad Line Region in Active Galactic Nuclei. I. Analytical Solution

Energy Technology Data Exchange (ETDEWEB)

Czerny, B.; Panda, S.; Wildy, C.; Sniegowska, M. [Center for Theoretical Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw (Poland); Li, Yan-Rong; Wang, J.-M. [Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, 19B Yuquan Road, Beijing 100049 (China); Hryniewicz, K.; Sredzinska, J. [Copernicus Astronomical Center, Polish Academy of Sciences, Bartycka 18, 00-716 Warsaw (Poland); Karas, V., E-mail: bcz@cft.edu.pl [Astronomical Institute, Academy of Sciences, Bocni II 1401, CZ-141 00 Prague (Czech Republic)

2017-09-10

The physical origin of the broad line region in active galactic nuclei is still unclear despite many years of observational studies. The reason is that the region is unresolved, and the reverberation mapping results imply a complex velocity field. We adopt a theory-motivated approach to identify the principal mechanism responsible for this complex phenomenon. We consider the possibility that the role of dust is essential. We assume that the local radiation pressure acting on the dust in the accretion disk atmosphere launches the outflow of material, but higher above the disk the irradiation from the central parts causes dust evaporation and a subsequent fallback. This failed radiatively accelerated dusty outflow is expected to represent the material forming low ionization lines. In this paper we formulate simple analytical equations to describe the cloud motion, including the evaporation phase. The model is fully described just by the basic parameters of black hole mass, accretion rate, black hole spin, and viewing angle. We study how the spectral line generic profiles correspond to this dynamic. We show that the virial factor calculated from our model strongly depends on the black hole mass in the case of enhanced dust opacity, and thus it then correlates with the line width. This could explain why the virial factor measured in galaxies with pseudobulges differs from that obtained from objects with classical bulges, although the trend predicted by the current version of the model is opposite to the observed trend.

Acute Radiation Effects Resulting from Exposure to Solar Particle Event-Like Radiation

Science.gov (United States)

Kennedy, Ann; Cengel, Keith

2012-07-01

A major solar particle event (SPE) may place astronauts at significant risk for the acute radiation syndrome (ARS), which may be exacerbated when combined with other space flight stressors, such that the mission or crew health may be compromised. The National Space Biomedical Research Institute (NSBRI) Center of Acute Radiation Research (CARR) is focused on the assessment of risks of adverse biological effects related to the ARS in animal models exposed to space flight stressors combined with the types of radiation expected during an SPE. As part of this program, FDA-approved drugs that may prevent and/or mitigate ARS symptoms are being evaluated. The CARR studies are focused on the adverse biological effects resulting from exposure to the types of radiation, at the appropriate energies, doses and dose-rates, present during an SPE (and standard reference radiations, gamma rays or electrons). The ARS is a phased syndrome which often includes vomiting and fatigue. Other acute adverse biologic effects of concern are the loss of hematopoietic cells, which can result in compromised bone marrow and immune cell functions. There is also concern for skin damage from high SPE radiation doses, including burns, and resulting immune system dysfunction. Using 3 separate animal model systems (ferrets, mice and pigs), the major ARS biologic endpoints being evaluated are: 1) vomiting/retching and fatigue, 2) hematologic changes (with focus on white blood cells) and immune system changes resulting from exposure to SPE radiation with and without reduced weightbearing conditions, and 3) skin injury and related immune system functions. In all of these areas of research, statistically significant adverse health effects have been observed in animals exposed to SPE-like radiation. Countermeasures for the management of ARS symptoms are being evaluated. New research findings from the past grant year will be discussed. Acknowledgements: This research is supported by the NSBRI Center of Acute

Image Guided Radiation Therapy (IGRT) Practice Patterns and IGRT's Impact on Workflow and Treatment Planning: Results From a National Survey of American Society for Radiation Oncology Members

Energy Technology Data Exchange (ETDEWEB)

Nabavizadeh, Nima, E-mail: nabaviza@ohsu.edu [Department of Radiation Medicine, Oregon Health & Science University, Portland, Oregon (United States); Elliott, David A. [Department of Radiation Medicine, Oregon Health & Science University, Portland, Oregon (United States); Chen, Yiyi [Division of Biostatistics, Department of Public Health and Preventative Medicine, Oregon Health & Science University, Portland, Oregon (United States); Kusano, Aaron S. [Department of Radiation Oncology, University of Washington, Seattle, Washington (United States); Mitin, Timur; Thomas, Charles R.; Holland, John M. [Department of Radiation Medicine, Oregon Health & Science University, Portland, Oregon (United States)

2016-03-15

Purpose: To survey image guided radiation therapy (IGRT) practice patterns, as well as IGRT's impact on clinical workflow and planning treatment volumes (PTVs). Methods and Materials: A sample of 5979 treatment site–specific surveys was e-mailed to the membership of the American Society for Radiation Oncology (ASTRO), with questions pertaining to IGRT modality/frequency, PTV expansions, method of image verification, and perceived utility/value of IGRT. On-line image verification was defined as images obtained and reviewed by the physician before treatment. Off-line image verification was defined as images obtained before treatment and then reviewed by the physician before the next treatment. Results: Of 601 evaluable responses, 95% reported IGRT capabilities other than portal imaging. The majority (92%) used volumetric imaging (cone-beam CT [CBCT] or megavoltage CT), with volumetric imaging being the most commonly used modality for all sites except breast. The majority of respondents obtained daily CBCTs for head and neck intensity modulated radiation therapy (IMRT), lung 3-dimensional conformal radiation therapy or IMRT, anus or pelvis IMRT, prostate IMRT, and prostatic fossa IMRT. For all sites, on-line image verification was most frequently performed during the first few fractions only. No association was seen between IGRT frequency or CBCT utilization and clinical treatment volume to PTV expansions. Of the 208 academic radiation oncologists who reported working with residents, only 41% reported trainee involvement in IGRT verification processes. Conclusion: Consensus guidelines, further evidence-based approaches for PTV margin selection, and greater resident involvement are needed for standardized use of IGRT practices.

Relationship between the intensity of nonthermal radiation and widths of Balmer lines in the spectra of quasar-like nuclei

International Nuclear Information System (INIS)

Komberg, B.V.; Shefer, E.Yu.

1983-01-01

The data summarized by Steiner (1981) were used to derive the relationship between the intensity of nonthermal X-ray and radio emission and fullwidths of Balmer emission lines. It is shown that the existence of such dependences does not contradict the assumption on partition equidistribution of nonthermal radiation and motion of gas clouds energy in the region of formation of wide lines. Emphasis is given to similar dependence drived by Vayana (1981) for X-ray radiation from hot coronas of fast-rotating single stars, and a suggestion is made about radiation anisotropy from active nuclei (similar to that observed in the SS 433 system). The latter may imply the double nature of active nuclei

Response of BP cell lines to γ-radiation: evaluation of DNA repair and apoptosis

International Nuclear Information System (INIS)

Paris, F.E.; Martin, M.; Le Rhum, Y.; May, E.; Duriez, P; Shah, G.

1997-01-01

In the BP cell lines, mutation of p53 gene is associated with an increased radiosensitivity. In order to understand the relation between p53 and radiosensitivity, we looked at DNA repair and cell death. Unexpectedly, after radiation the mutated p53 cell line BPp- Tu and the wild type p53 cell line BPp- Tu cells, both ell lines died by the same non necrotic process: a programmed cell death independent of their p53 status. The cleavage of poly (ADP-ribose) polymerase (PARP) by an ICE-related protease is considered an early and critical event during apoptosis. The fate of PARP was monitored by Western extensively in the apoptotic BPp- Tu cells than in the BPp cells. This faster PARP cleavage might be linked to the increased radiosensitivity of the BPp- Tu cells. (authors)

Determination of gamma radiation lethal dose (LD{sub 50}) and resveratrol cytotoxicity level in tumor cells line

Energy Technology Data Exchange (ETDEWEB)

Magalhaes, Vanessa D.; Rogero, Sizue O.; Rogero, Jose R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Cruz, Aurea S. [Instituto Adolfo Lutz (IAL-SP) Secao de Culturas Celulares, SP (Brazil)

2011-07-01

Cancer is a disease with high incidence and it is considered a worldwide public health problem. Resveratrol is a polyphenol occurring naturally in a wide variety of plants according to response of ultraviolet radiation (UV) exposition or according to mechanical stress resulting of pathogens or chemical and physical agents. This polyphenol possesses a pharmacological activity of carcinogenesis inhibition in multiple levels. It also protects cells by scavenging the free radicals which are considered toxic products. These free radicals are formed of natural process of cell aging and also by incidence of ionizing radiation in the organism. Thus, resveratrol is considered as a cell radioprotector. On the other hand, in some elevated concentrations resveratrol may be considered as a radiosensitizing. The aim of this work was the determination of radiation lethal dose (LD{sub 50}) and also verifies the cytotoxicity level of resveratrol in tumor cells line: muco epidermoid pulmonary carcinoma cells (NCI-H292) and rhabdomyosarcoma cells (RD). The cytotoxicity test was performed by neutral red uptake assay. The results of resveratrol IC{sub 50%} in NCI-H292 cells was 192{mu}M and in RD cells was 128{mu}M; and RD cells gamma radiation LD{sub 50} was 435Gy. (author)

Chromatin status of apoptosis genes correlates with sensitivity to chemo-, immune- and radiation therapy in colorectal cancer cell lines.

Science.gov (United States)

Benard, Anne; Janssen, Connie M; van den Elsen, Peter J; van Eggermond, Marja C J A; Hoon, Dave S B; van de Velde, Cornelis J H; Kuppen, Peter J K

2014-12-01

The apoptosis pathway of programmed cell death is frequently deregulated in cancer. An intact apoptosis pathway is required for proper response to anti-cancer treatment. We investigated the chromatin status of key apoptosis genes in the apoptosis pathway in colorectal cancer cell lines in relation to apoptosis induced by chemo-, immune- or radiation therapy. Using chromatin immunoprecipitation (ChIP), we measured the presence of transcription-activating histone modifications H3Ac and H3K4me3 and silencing modifications H3K9me3 and H3K27me3 at the gene promoter regions of key apoptosis genes Bax, Bcl2, Caspase-9, Fas (CD95) and p53. Cell lines DLD1, SW620, Colo320, Caco2, Lovo and HT29 were treated with cisplatin, anti-Fas or radiation. The apoptotic response was measured by flow cytometry using propidium iodide and annexin V-FITC. The chromatin status of the apoptosis genes reflected the activation status of the intrinsic (Bax, Bcl2, Caspase-9 and p53) and extrinsic (Fas) pathways. An active intrinsic apoptotic pathway corresponded to sensitivity to cisplatin and radiation treatment of cell lines DLD1, SW620 and Colo320. An active Fas promoter corresponded to an active extrinsic apoptotic pathway in cell line DLD1. mRNA expression data correlated with the chromatin status of the apoptosis genes as measured by ChIP. In conclusion, the results presented in this study indicate that the balance between activating and silencing histone modifications, reflecting the chromatin status of apoptosis genes, can be used to predict the response of tumor cells to different anti-cancer therapies and could provide a novel target to sensitize tumors to obtain adequate treatment responses.

Radiation studied on the internet. On-line radiation teaching materials

International Nuclear Information System (INIS)

Inoue, Hiroyoshi; Kagoshima, Mayumi; Yamasaki, Mariko

2005-01-01

In order to facilitate scientific understanding of radiation in Japan where social understanding has been already progressed, we developed Internet radiation teaching materials that can be utilized as off-school teaching materials or supplementary materials. The teaching materials of ''atomic structure and radiation'' and ''medical treatment and radiation'' were tried for 160 high school students and 59 junior high school students, respectively. More than 70% of the student answered that these teaching materials were effective when they understand radiation. (author)

Detection of radiation-induced hydrocarbons in Camembert irradiated before and after the maturing process-comparison of florisil column chromatography and on-line coupled liquid chromatography-gas chromatography

International Nuclear Information System (INIS)

Schulzki, G.; Spiegelberg, A.; Bögl, K.W.; Schreiber, G.A.

1995-01-01

The influence of the maturing process on the detection of radiation-induced volatile hydrocarbons in the fat of Camembert has been investigated. Two analytical methods for separation of the hydrocarbon fraction from the lipid were applied: Florisil column chromatography with subsequent gas chromatographic-mass spectrometric (GC-MS) determination as well as on-line coupled liquid chromatography-GC-MS. The maturing process had no influence on the detection of radiation-induced volatiles. Comparable results were achieved with both analytical methods. However, preference is given to the more effective on-line coupled LC-GC method

Lithium line radiation in turbulent edge plasmas: Effects of low and high frequency temperature fluctuations

Science.gov (United States)

Rosato, J.; Capes, H.; Catoire, F.; Kadomtsev, M. B.; Levashova, M. G.; Lisitsa, V. S.; Marandet, Y.; Rosmej, F. B.; Stamm, R.

2011-08-01

In lithium-wall-conditioned tokamaks, the line radiation due to the intrinsic impurities (Li/Li+/Li++) plays a significant role on the power balance. Calculations of the radiation losses are usually performed using a stationary collisional-radiative model, assuming constant values for the plasma parameters (Ne, Te,…). Such an approach is not suitable for turbulent plasmas where the various parameters are time-dependent. This is critical especially for the edge region, where the fluctuation rates can reach several tens of percents [e.g. J.A. Boedo, J. Nucl. Mater. 390-391 (2009) 29-37]. In this work, the role of turbulence on the radiated power is investigated with a statistical formalism. A special emphasis is devoted to the role of temperature fluctuations, successively for low-frequency fluctuations and in the general case where the characteristic turbulence frequencies can be comparable to the collisional and radiative rates.

Using RADMC-3D to model the radiative transfer of spectral lines in protoplanetary disks and envelopes

Science.gov (United States)

DeVries, John; Terebey, Susan

2018-06-01

Protoplanetary disks are the birthplaces of planets in our universe. Observations of these disks with radio telescopes like the Atacama Large Millimeter Array (ALMA) offer great insight into the star and planet formation process. Comparing theories of formation with observations requires tracing the energy transfer via electromagnetic radiation, known as radiative transfer. To determine the temperature distribution of circumstellar material, a Monte Carlo code (Whitney et al. [1]) was used to to perform the radiative transfer through dust. The goal of this research is to utilize RADMC-3D [2] to handle the spectral line radiative transfer computations. An existing model of a rotating ring was expanded to include emission from the C18O isotopologue of carbon monoxide using data from the Leiden Atomic and Molecular Database (LAMDA). This feature of our model compliments ALMA's ability to measure C18O line emission, a proxy for disk rotation. In addition to modeling gas in the protoplanetary disk, dust also plays an important role. The generic description of absorption and scattering for dust provided by RADMC-3D was changed in favor of a more physically-realistic description with OH5 grains. This description is more appropriate in high-density regions of the envelope around a protostar. Further improvements, such as consideration for the finite resolution of observations, have been implemented. The task at present is to compare our model with observations of protoplanetary systems like L1527. Some results of these comparisons will be presented.[1] Whitney et al. 2013, ApJS, 207:30[2] RADMC-3D: http://www.ita.uni-heidelberg.de/~dullemond/software/radmc-3d/

Radiation effects in ice: New results

International Nuclear Information System (INIS)

Baragiola, R.A.; Fama, M.; Loeffler, M.J.; Raut, U.; Shi, J.

2008-01-01

Studies of radiation effects in ice are motivated by intrinsic interest and by applications in astronomy. Here we report on new and recent results on radiation effects induced by energetic ions in ice: amorphization of crystalline ice, compaction of microporous amorphous ice, electrostatic charging and dielectric breakdown and correlated structural/chemical changes in the irradiation of water-ammonia ices

Impacts of microphysics, radiation and environmental winds in mid-latitude and tropical squall-line systems, and their climatic implications

International Nuclear Information System (INIS)

Chin, Hung-Neng.

1994-08-01

Cloud-radiation feedback has been identified as the most important factor limiting general circulation models (GCMS) to further progress in climate change research (Cess et al., 1989). It is also regarded as a major uncertainty in estimating the impact of greenhouse gases on climate simulations. As a result, many GCMs showed high sensitivity to the treatment of clouds and cloud radiative properties. Therefore, a better understanding of cloud-radiation feedback on the large-scale environment is absolutely essential to improve the representation of cloud processes in GCMS. To this end, a cloud model with enhanced model physics is used to study the impact of cloud-radiation interactions on mesoscale convective systems (MCSs). Case studies representing a variety of convective systems are important to generalize the overall effects of anvil clouds on the large-scale environment. Our primary interesting is limited to the MCSs in an environment with substantial wind shear, such as squall-line systems, because they have longer lifetime and wider coverage to impact the earth radiation budget and climate. The objective of this study is to investigate the impacts of microphysics, radiation and environmental winds on mid-latitude continental and tropical oceanic squall-line systems. Comparisons between these two systems are presented. Recent studies indicated that the vertical shear of the environmental wind plays an important role in the formation of the anvil cloud through the tilting of MCSS. However, this process has not been represented in GCMS. A detailed investigation on the formation of anvil clouds and their relationship to cumulus portions of MCSs would help develop a better cloud parameterization for use in GCMS. Two important issues are addressed through these comparisons. First, what factors cause the differences between mid-latitude and tropical anvil clouds? Second, do these differences have climatic implications to improve our climate forecasting ability?

Study of different registration methods for on-line kilovoltage cone-beam CT guided lung cancer radiation

International Nuclear Information System (INIS)

Wang Yanyang; Fu Xiaolong; Xia Bing; Wu Zhengqin; Fan Min; Yang Huanjun; Xu Zhiyong; Jiang Guoliang

2009-01-01

Objective: To select the optimal registration method for on-line kilovoltage cone-beam CT (KVCBCT) guided lung cancer radiation and evaluate the reproducibility of the selected method. Methods: Sixteen patients with non-small cell lung cancer were enrolled into this study. A total of 96 pretreatment KVCBCT images from the 16 patients were available for the analysis. Image registration methods were bone-based automatic registration, gray-based automatic registration, manual registration and semi-automatic registration. All registrations were accomplished by one physician. Another physician blindly evaluated the results of each registration, then selected the optimal registration method and evaluated its reproducibility. Results: The average score of the bone-based automatic registration, gray-based automatic registration, manual registration and semi-automatic registration methods was 2.4, 2.7, 3.0 and 3.7, respectively. The score of the four different groups had statistics significant difference (F=42.20, P<0.001). Using the semi-automatic registration method, the probability of the difference between two registration results more than 3 mm in the left-right, superior-inferior, and anterior-posterior directions was 0, 3% and 6% by the same physician, 0, 14% and 0 by different physicians, and 8%, 14% and 8% by physician and radiation therapist. Conclusions: Semi-automatic registration method, possessing the highest score and accepted reproducibility, is appropriate for KVCBCT guided lung cancer radiation. (authors)

Lithium line radiation in turbulent edge plasmas: Effects of low and high frequency temperature fluctuations

Energy Technology Data Exchange (ETDEWEB)

Rosato, J., E-mail: joel.rosato@univ-provence.fr [PIIM, UMR 6633, Universite de Provence/CNRS, Centre de St.-Jerome, Case 232, F-13397 Marseille Cedex 20 (France); Capes, H.; Catoire, F. [PIIM, UMR 6633, Universite de Provence/CNRS, Centre de St.-Jerome, Case 232, F-13397 Marseille Cedex 20 (France); Kadomtsev, M.B.; Levashova, M.G.; Lisitsa, V.S. [ITP, Russian Research Center ' Kurchatov Institute' , Moscow (Russian Federation); Marandet, Y. [PIIM, UMR 6633, Universite de Provence/CNRS, Centre de St.-Jerome, Case 232, F-13397 Marseille Cedex 20 (France); Rosmej, F.B. [LULI, UMR 7605, Universite Pierre et Marie Curie/CNRS, 4 Place Jussieu, Case 128, F-75252 Paris Cedex 05 (France); Stamm, R. [PIIM, UMR 6633, Universite de Provence/CNRS, Centre de St.-Jerome, Case 232, F-13397 Marseille Cedex 20 (France)

2011-08-01

In lithium-wall-conditioned tokamaks, the line radiation due to the intrinsic impurities (Li/Li{sup +}/Li{sup ++}) plays a significant role on the power balance. Calculations of the radiation losses are usually performed using a stationary collisional-radiative model, assuming constant values for the plasma parameters (N{sub e}, T{sub e},...). Such an approach is not suitable for turbulent plasmas where the various parameters are time-dependent. This is critical especially for the edge region, where the fluctuation rates can reach several tens of percents [e.g. J.A. Boedo, J. Nucl. Mater. 390-391 (2009) 29-37]. In this work, the role of turbulence on the radiated power is investigated with a statistical formalism. A special emphasis is devoted to the role of temperature fluctuations, successively for low-frequency fluctuations and in the general case where the characteristic turbulence frequencies can be comparable to the collisional and radiative rates.

Magnetospheric line radiation: 6.5 years of observations by the DEMETER spacecraft

Czech Academy of Sciences Publication Activity Database

Bezděková, B.; Němec, F.; Parrot, M.; Santolík, Ondřej; Krupařová, Oksana

2015-01-01

Roč. 120, č. 11 (2015), s. 9442-9456 ISSN 2169-9380 R&D Projects: GA ČR(CZ) GAP209/11/2280; GA ČR(CZ) GA14-31899S; GA ČR GP13-37174P; GA MŠk LH12231 Institutional support: RVO:68378289 Keywords : magnetospheric line radiation * MLR * DEMETER Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.318, year: 2015 http://onlinelibrary.wiley.com/doi/10.1002/2015JA021246/full

Fluorescent L-radiation and the. gamma. -radiation of ionium

Energy Technology Data Exchange (ETDEWEB)

Riou, M

1949-02-21

Irene Curie, Compt. rend. 227, 1225(1948), has shown that the ..gamma..-radiation of ionium is accompanied by a soft radiation that can be identified with the fluorescent L-lines of radium. The present author submitted these radiations to a further study, using as a source a ionium--thorium mixture, (100 mg of hydrate), containing 9% ionium. The Geiger--Mueller counters had 5 mg/cm/sup 2/ aluminum ends and were filled with alcohol + xenon at 10-21 cm Hg. The absorption curves in Cu, Mo, and Ag showed that the energy of the soft radiation was about 14 keV. For the separation of lines, the selective absorption was determined in elements from Z = 28 to Z = 53. The results confirmed the attribution of the spectrum to the L-radiation of Ra. Similar measurements on radioactinium revealed the same lines with approximately the same intensities. In both cases a radium isotope is formed: /sub 90/Th/sup 230/(Io) ..-->.. /sub 88/Ra/sup 226/ ..-->.. ..cap alpha.., /sub 90/Th/sup 227/ (RaAc) ..-->.. /sub 88/Ra/sup 223/ (AcX) + ..cap alpha... The identity of the spectra shows that the atomic number of the formed atom alone determines the L-spectrum, and that in both cases the L level is excited as a result of an internal conversion of ..gamma..-lines: the line 68 keV in the case of ionium, eight lines 26-100 keV in that of radioactinium. On the basis of the intensities found, the relative numbers of photons corresponding to the levels L/sub I/, L/sub II/, and L/sub III/ could be calculated; they are L/sub I/:L/sub II/:L/sub III/ = 50:20:26. The ..gamma..-rays of ionium, as determined from the absorption in Cu, Ta, and Pb, are 68 and 200 kev. By assuming that the efficiency of the counters is equal to 1 - exp (-m..mu../rho), (where m is the efficient superficial mass of xenon, and ..mu../rho is the absorption coefficient in xenon), the intensities of the L- and ..gamma..-radiations of ionium can be given in terms of numbers of quanta per 100 disintegrations.

Comparison of radiation sensitivity for three cell lines as measured by the cloning assay and the micro-nucleus test

NARCIS (Netherlands)

Stap, J.; Aten, J. A.

1990-01-01

The correlation between cell killing and the induction of micro-nuclei was studied for three cell lines after treatment with gamma radiation to investigate whether the frequency of micro-nucleated cells can be used to determine the radiation sensitivity of a cell type. R1 rat rhabdomyosarcoma cells

A web based on-line radiation early warning system for emergency preparedness and response centre

International Nuclear Information System (INIS)

Bhujbal, Vaibhav; Saindane, Shashank S.; Narasaiah, M.V.R.; Murali, S.

2018-01-01

The topography of the Bhabha Atomic Research Centre, Trombay site, where all major components of nuclear fuel cycle activities are located is very complex in nature. The assessment of the radiological impact, if any, due to atmospheric releases from these facilities within BARC site is being carried out by using a Local Area Network (LAN) based Radiation Early Warning System and meteorological parameters. The upgraded system is aimed at providing data during normal operation of the various facilities at site and for providing early warning to decision makers in case of any onset of an emergency. It is carried out by acquiring both on-line and off-line data on releases from the plants, the environmental radiation dose rate at selected locations and other related parameters. The monitors placed at these selected locations including strategic point around the BARC site can also help in detecting any attempt of unauthorized trafficking of the radioactive sources. This paper explains different aspects of the system operating at BARC

Analysis of Information Leakages on Laser Printers in the Media of Electromagnetic Radiation and Line Conductions

OpenAIRE

Ulaş, Cihan

2016-01-01

In this paper, the emissions of a laser printer, which may process classified information, are investigated in the media of electromagnetic radiation (ER), Power Line Conductors (PLC), and Signal Line Conductors (SLC). First, the candidate frequency points of CE are examined in the frequency domain. Second, the emitted signal is AM-demodulated with the proper bandwidth, and then sampled by a high storage oscilloscope in these frequency points. Third, the collected data is converted to 2D imag...

In vitro oxygen-dependent survival of two human cell lines after combined radiations tirapazamin and cisplatin

International Nuclear Information System (INIS)

Lartigau, E.; Stern, S.; Guichard, M.

2000-01-01

Recent data have shown that the in vitro and in vivo cytotoxicity of bioreductive drugs could be significantly cytotoxicity of bioreductive drugs could be significantly increased by combination with ionising radiation or chemotherapy. Various parameters such as oxygen tension and timing of administration of the drugs could play a crucial role in the efficacy of combined treatment modalities. The aim of this study was to define the oxygen dependency of cell survival after in vitro irradiation and incubation with tirapazamin, a bioreductive drug, and cisplatin given alone or simultaneously. Two human cell lines were studied: one cell line sensitive to tirapazamin, Na11+, a pigmented melanoma with a high percentage of hypoxic cells, and a less sensitive cell line to tirapazamin, HRT18, a rectal adenocarcinoma. Gas changes were made to study cell survival at four different oxygen concentrations (pO 2 ): air (20.9 % O 2 ), 10.2 and 0.2 %. Cells were incubated with tirapazamin and cisplatin alone or combined for one hour at 37 deg C, then irradiated and cultured. For Na11+, cell survival after irradiation was comparable in air and at 10 % oxygen with the two drugs given alone or combined. At 2 and 0.2 % oxygen, cell killing was largely increased by tirapazamin and was not modified by the addition of cisplatin. For HRT18, cell survival was not modified when cisplatin was added to radiation, whatever the oxygen partial pressure. At low pO 2 (2 and 0.2 %) the cytotoxic effect of tirapazamin was not significantly decreased by the addition of cisplatin. When cytotoxic and bioreductive drugs are combined to radiation, the magnitude of the observed effect is highly dependent on the partial oxygen pressure and on the sensitivity of the cell line to the individual drugs. This has very important implications for clinical strategies based on combined chemo-radiotherapy. (authors)

Radiation response of drug-resistant variants of a human breast cancer cell line

International Nuclear Information System (INIS)

Lehnert, S.; Greene, D.; Batist, G.

1989-01-01

The radiation response of drug-resistant variants of the human tumor breast cancer cell line MCF-7 has been investigated. Two sublines, one resistant to adriamycin (ADRR) and the other to melphalan (MLNR), have been selected by exposure to stepwise increasing concentrations of the respective drugs. ADRR cells are 200-fold resistant to adriamycin and cross-resistant to a number of other drugs and are characterized by the presence of elevated levels of selenium-dependent glutathione peroxidase and glutathione-S-transferase. MLNR cells are fourfold resistant to melphalan and cross-resistant to some other drugs. The only mechanism of drug resistance established for MLNR cells to date is an enhancement of DNA excision repair processes. While the spectrum of drug resistance and the underlying mechanisms differ for the two sublines, their response to radiation is qualitatively similar. Radiation survival curves for ADRR and MLNR cells differ from that for wild-type cells in a complex manner with, for the linear-quadratic model, a decrease in the size of alpha and an increase in the size of beta. There is a concomitant decrease in the size of the alpha/beta ratio which is greater for ADRR cells than for MLNR cells. Analysis of results using the multitarget model gave values of D0 of 1.48, 1.43, and 1.67 Gy for MCF-7 cells are not a consequence of cell kinetic differences between these sublines. Results of split-dose experiments indicated that for both drug-resistant sublines the extent of sublethal damage repair reflected the width of the shoulder on the single-dose survival curve. For MCF-7 cells in the stationary phase of growth, the drug-resistant sublines did not show cross-resistance to radiation; however, delayed subculture following irradiation of stationary-phase cultures increased survival to a greater extent for ADRR and MLNR cells than for wild-type cells

Effects of gamma radiation on the OM431 human ocular melanoma cell line

International Nuclear Information System (INIS)

Logani, S.; Cho, A.S.; Su, L.D.; Withers, H.R.; McBride, W.H.; Hall, M.O.; Lee, D.A.; Milani, J.K.; Straatsma, B.R.

1995-01-01

In order to determine the dose responsiveness to radiation of ocular melanoma, we conducted an in vitro dose-response study on a monolayer cell culture using a clonogenic assay. The effects on cell survival were determined relative to unirradiated controls. A human epithelioid ocular melanoma cell line, OM431, was maintained in tissue culture and serial dilutions of viable cells were plated in flasks, allowed to settle and attach for 48 h, and subsequently irradiated with 1-10 Gy in single fractions. After 2 weeks, the number of reproducing clones (forming colonies with greater than 32 cells or five generations) were counted. The surviving fractions of cells were plotted on a cell survival curve using the linear quadratic model. The survival curve showed a large initial shoulder followed by an exponential decline in growth. Our data suggest that the OM431 ocular melanoma cell line responds to irradiation in a manner similar to other melanoma cell lines and is relatively radioresistent especially at lower doses. (author)

A New Radio Spectral Line Survey of Planetary Nebulae: Exploring Radiatively Driven Heating and Chemistry of Molecular Gas

Science.gov (United States)

Bublitz, Jesse

Planetary nebulae contain shells of cold gas and dust whose heating and chemistry is likely driven by UV and X-ray emission from their central stars and from wind-collision-generated shocks. We present the results of a survey of molecular line emissions in the 88 - 235 GHz range from nine nearby (Radioastronomie Millimetrique. Rotational transitions of nine molecules, including the well-studied CO isotopologues and chemically important trace species, were observed and the results compared with and augmented by previous studies of molecular gas in PNe. Lines of the molecules HCO+, HNC, HCN, and CN, which were detected in most objects, represent new detections for five planetary nebulae in our study. Flux ratios were analyzed to identify correlations between the central star and/or nebular ultraviolet/X-ray luminosities and the molecular chemistries of the nebulae. Analysis reveals the apparent dependence of the HNC/HCN line ratio on PN central star UV luminosity. There exists no such clear correlation between PN X-rays and various diagnostics of PN molecular chemistry. The correlation between HNC/HCN ratio and central star UV luminosity hints at the potential of molecular emission line studies of PNe for improving our understanding of the role that high-energy radiation plays in the heating and chemistry of photodissociation regions.

Radiation resistant fiber Bragg grating in random air-line fibers for sensing applications in nuclear reactor cores.

Science.gov (United States)

Zaghloul, Mohamed A S; Wang, Mohan; Huang, Sheng; Hnatovsky, Cyril; Grobnic, Dan; Mihailov, Stephen; Li, Ming-Jun; Carpenter, David; Hu, Lin-Wen; Daw, Joshua; Laffont, Guillaume; Nehr, Simon; Chen, Kevin P

2018-04-30

This paper reports the testing results of radiation resistant fiber Bragg grating (FBG) in random air-line (RAL) fibers in comparison with FBGs in other radiation-hardened fibers. FBGs in RAL fibers were fabricated by 80 fs ultrafast laser pulse using a phase mask approach. The fiber Bragg gratings tests were carried out in the core region of a 6 MW MIT research reactor (MITR) at a steady temperature above 600°C and an average fast neutron (>1 MeV) flux >1.2 × 10 14 n/cm 2 /s. Fifty five-day tests of FBG sensors showed less than 5 dB reduction in FBG peak strength after over 1 × 10 20 n/cm 2 of accumulated fast neutron dose. The radiation-induced compaction of FBG sensors produced less than 5.5 nm FBG wavelength shift toward shorter wavelength. To test temporal responses of FBG sensors, a number of reactor anomaly events were artificially created to abruptly change reactor power, temperature, and neutron flux over short periods of time. The thermal sensitivity and temporal responses of FBGs were determined at different accumulated doses of neutron flux. Results presented in this paper reveal that temperature-stable Type-II FBGs fabricated in radiation-hardened fibers can survive harsh in-pile conditions. Despite large parameter drift induced by strong nuclear radiation, further engineering and innovation on both optical fibers and fiber devices could lead to useful fiber sensors for various in-pile measurements to improve safety and efficiency of existing and next generation nuclear reactors.

Transcriptome-wide studies of prostate cancer cell lines in the context of medical radiation; Transkriptomweite Untersuchungen von Prostata-Krebszelllinien im Kontext medizinischer Strahlentherapie

Energy Technology Data Exchange (ETDEWEB)

Hammer, Paul

2012-06-26

The use of radiotherapy in addition to chemotherapy and surgical removal is the most powerful instrument in the fight against malignant tumors in cancer medicine. After cardiovascular diseases, cancer is the second leading cause of death in the western world, in which prostate cancer is the most frequent male cancer. Despite continuous technological improvements in radiological instruments and prognosis, it may occur a recurrence up to many years after radiotherapy due to a high resistance capability of individual malignant cells of the locally occurring tumor. Although modern radiation biology has studied many aspects of the resistance mechanisms, questions are largely unanswered especially in regards to prognostic terms and time response of tumor cells to ionizing radiation. As cellular models four prostate cancer cell lines with different radiation sensitivities (PC3, DuCaP, DU-145, RWPE-1) were cultured and tested for their ability to survive after exposure to ionizing radiation by a trypane blue and MTT viability assay. The proliferative capacity of the four cell lines was determined using a colony formation assay. The PC3 cell line (radiation-resistant) and the DuCaP cell line (radiation-sensitive) showed the maximal differences in terms of radiation sensitivity. Based on these results the two cell lines were selected to allow identification of potential prognostic marker for predicting the effectiveness of radiation therapy via their transcriptome-wide gene expression. Furthermore, a time series experiment with the radiation-resistant PC3 cell line was performed. At 8 different time points, during the period from 00:00 - 42:53 (hh:mm) after exposure with 1 Gy, the mRNA was quantified by next generation sequencing to investigate the dynamic behavior of time-delayed gene expression and to discover resistance mechanisms. Of 10,966 expressed genes 730 were significant differentially expressed, determined by setting a fold change threshold in conjunction with a P

The tension adjuster used at the work line of electron beam radiation cross-linking wire and cable

International Nuclear Information System (INIS)

Zhang Yingfa; Liu Zhenhao; Yin Xuejun

1999-01-01

The tension adjuster is an important equipment in the transport system at the work line of electron beam radiation cross-linking wire and cable to realize the velocity synchronism. There are many kinds of the adjuster. By putting various adjusters together properly, the authors can keep the line work stable and raise the quality of the product. Two kinds of standing adjuster and their mechanism are introduced. Also the corresponding figures and formulas are shown

Carboplatin- and cisplatin-induced potentiation of moderate-dose radiation cytotoxicity in human lung cancer cell lines

NARCIS (Netherlands)

Groen, H. J.; Sleijfer, S.; Meijer, C.; Kampinga, H. H.; Konings, A. W. T.; de Vries, E. G. E.; Mulder, N. H.

1995-01-01

The interaction between moderate-dose radiation and cisplatin or carboplatin was studied in a cisplatin-sensitive (GLC(4)) and -resistant (GLC(4)-CDDP) human small-cell lung cancer cell line. Cellular toxicity was analysed under oxic conditions with the microculture tetrazolium assay. For the

Wideband analysis of railway catenary line radiation and new applications of its unintentional emitted signals

Science.gov (United States)

Heddebaut, Marc; Deniau, Virginie; Rioult, Jean

2018-06-01

Generally, in railway networks, dissipated energy—and its consequences in terms of noise, ballast attrition, electromagnetic interference, etc—is considered a nuisance generated by this means of transport. Therefore, most studies are carried out with the aim of reducing it. This paper takes the opposite view and considers the particular case of the irreducible electromagnetic interference generated along an electrified line, in order to propose new applications beneficial to railway operations. At a selected representative location, wideband (ranging from 10 kHz to 1 GHz) electromagnetic field measurements are performed successively during, and not during, high speed train passages. We deduce two potential applications of these unintentional signals. At low frequency, the first proposal considers energy harvesting using the received electromagnetic interference as the source. This received energy can be converted and used to DC feed low consumption sensors to be installed along the railway infrastructure. These sensors participate in monitoring infrastructure health and in making it more resilient to internal and external stresses. At higher frequencies, for the second proposal, radiation from the catenary line and train pantograph is specifically examined at a carefully selected sub-band. The results are also studied following a time–frequency analysis, to introduce a new nondestructive inspection method of the sliding contact between the catenary line and the train pantograph. Ultimately, this technique could offer a new means of monitoring the health of both the catenary line and the pantograph.

Intensities of decimetric-wavelength radio recombination lines

International Nuclear Information System (INIS)

Parrish, A.; Pankonin, V.

1975-01-01

We summarize the intensity results of some of the 221 and 248α recombination-line observations taken with the Arecibo telescope, and report additional results including 166α observations from the NRAO 300-foot (91 m) telescope. The brightness temperatures of these lines increase sharply with wavelength. We show that these results require that the upper levels of the recombining atoms be overpopulated with respect to LTE conditions. The most reasonable interpretation of the results is that the line emission at these decimetric wavelengths is stimulated by a background source of continuum radiation

Experimental Study of Coherent Synchrotron Radiation in the Emittance Exchange Line at the A0-Photoinjector

Science.gov (United States)

Thangaraj, Jayakar C. T.; Thurman-Keup, R.; Johnson, A.; Lumpkin, A. H.; Edwards, H.; Ruan, J.; Santucci, J.; Sun, Y. E.; Church, M.; Piot, P.

2010-11-01

Next generation accelerators will require a high current, low emittance beam with a low energy spread. Such accelerators will employ advanced beam conditioning systems such as emittance exchangers to manipulate high brightness beams. One of the goals of the Fermilab A0 photoinjector is to investigate the transverse to longitudinal emittance exchange principle. Coherent synchrotron radiation could limit high current operation of the emittance exchanger. In this paper, we report on the preliminary experimental and simulation study of the coherent synchroton radiation (CSR) in the emittance exchange line at the A0 photoinjector.

Line photon transport in a non-homogeneous plasma using radiative coupling coefficients

International Nuclear Information System (INIS)

Florido, R.; Gil, J.M.; Rodriguez, R.; Rubiano, J.G.; Martel, P.; Florido, R.; Gil, J.M.; Rodriguez, R.; Rubiano, J.G.; Martel, P.; Minguez, E.

2006-01-01

We present a steady-state collisional-radiative model for the calculation of level populations in non-homogeneous plasmas with planar geometry. The line photon transport is taken into account following an angle- and frequency-averaged escape probability model. Several models where the same approach has been used can be found in the literature, but the main difference between our model and those ones is that the details of geometry are exactly treated in the definition of coupling coefficients and a local profile is taken into account in each plasma cell. (authors)

Effect of an aminothiol (WR-1065) on radiation-induced mutagenesis and cytotoxicity in two repair-deficient mammalian cell lines

International Nuclear Information System (INIS)

Grdina, D.J.; Nagy, B.; Meechan, P.J.

1991-01-01

WR-2721 and its free thiol WR-1065 have been found to effectively protect against radiation- and/or chemotherapy-induced mutagenesis, transformation and carcinogenesis. With respect to the antimutagenic effect, WR-1065 significantly reduced the frequency of HGPRT mutants even when it was administered up to three hours following exposure of cells to radiation. The mechanisms of action most often attributed to these agents include their ability to scavenge free radicals, enter into chemical repair processes through the donation of hydrogen atoms, and induce intracellular hypoxia by means of auto-oxidative processes. Although evidence exists for each of these processes, none is sufficiently satisfactory to account for the post-irradiation protection of WR-1065 against mutation induction in mammalian cells. The most elegant work describing the role of aminothiols on cellular enzymatic repair processes has focused on well-characterized repair-proficient and -deficient bacterial and yeast cell systems. Protection against radiation-induced cytotoxicity by the aminothiol cysteamine was absent in E. coli cell lines that were characterized as having genetically defective repair systems. Until recently, such studies could not be effectively performed with mammalian cells. However, with the isolation and characterization of rodent cell lines deficient in their ability to repair DNA damage, it is now possible to investigate the role of cell-mediated repair systems on aminothiol radioprotection. Specifically, the authors have investigated the effects of WR-1065 on radiation-induced mutagenesis and cytotoxicity in cell lines EM9 and xrs-5, which are defective in DNA single-strand break (SSB) and double-strand break (DSB) rejoining, respectively. Corresponding parental repair-proficient cell lines, AA8 and K1, were also studied for comparative purposes. 26 refs., 5 figs., 2 tabs

Distinct Signaling Pathways After Higher or Lower Doses of Radiation in Three Closely Related Human Lymphoblast Cell Lines

International Nuclear Information System (INIS)

Lu, T.-P.; Lai, L.-C.; Lin, B.-I.; Chen, L.-H.; Hsiao, T.-H.; Liber, Howard L.; Cook, John A.; Mitchell, James B.; Tsai, M.-H.; Chuang, Eric Y.

2010-01-01

Purpose: The tumor suppressor p53 plays an essential role in cellular responses to DNA damage caused by ionizing radiation; therefore, this study aims to further explore the role that p53 plays at different doses of radiation. Materials and Methods: The global cellular responses to higher-dose (10 Gy) and lower dose (iso-survival dose, i.e., the respective D0 levels) radiation were analyzed using microarrays in three human lymphoblast cell lines with different p53 status: TK6 (wild-type p53), NH32 (p53-null), and WTK1 (mutant p53). Total RNAs were extracted from cells harvested at 0, 1, 3, 6, 9, and 24 h after higher and lower dose radiation exposures. Template-based clustering, hierarchical clustering, and principle component analysis were applied to examine the transcriptional profiles. Results: Differential expression profiles between 10 Gy and iso-survival radiation in cells with different p53 status were observed. Moreover, distinct gene expression patterns were exhibited among these three cells after 10 Gy radiation treatment, but similar transcriptional responses were observed in TK6 and NH32 cells treated with iso-survival radiation. Conclusions: After 10 Gy radiation exposure, the p53 signaling pathway played an important role in TK6, whereas the NFkB signaling pathway appeared to replace the role of p53 in WTK1. In contrast, after iso-survival radiation treatment, E2F4 seemed to play a dominant role independent of p53 status. This study dissected the impacts of p53, NFkB and E2F4 in response to higher or lower doses of γ-irradiation.

Chromosomal Aberrations in DNA Repair Defective Cell Lines: Comparisons of Dose Rate and Radiation Quality

Science.gov (United States)

George, K. A.; Hada, M.; Patel, Z.; Huff, J.; Pluth, J. M.; Cucinotta, F. A.

2009-01-01

Chromosome aberration yields were assessed in DNA double-strand break repair (DSB) deficient cells after acute doses of gamma-rays or high-LET iron nuclei, or low dose-rate (0.018 Gy/hr) gamma-rays. We studied several cell lines including fibroblasts deficient in ATM (product of the gene that is mutated in ataxia telangiectasia patients) or NBS (product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase, DNA-PK activity. Chromosomes were analyzed using the fluorescence in-situ hybridization (FISH) chromosome painting method in cells at the first division post-irradiation and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving >2 breaks in 2 or more chromosomes). Gamma radiation induced higher yields of both simple and complex exchanges in the DSB repair defective cells than in the normal cells. The quadratic dose-response terms for both chromosome exchange types were significantly higher for the ATM and NBS defective lines than for normal fibroblasts. However, the linear dose-response term was significantly higher only for simple exchanges in the NBS cells. Large increases in the quadratic dose response terms indicate the important roles of ATM and NBS in chromatin modifications that facilitate correct DSB repair and minimize aberration formation. Differences in the response of AT and NBS deficient cells at lower doses suggests important questions about the applicability of observations of radiation sensitivity at high dose to low dose exposures. For all iron nuclei irradiated cells, regression models preferred purely linear and quadratic dose responses for simple and complex exchanges, respectively. All the DNA repair defective cell lines had lower Relative biological effectiveness (RBE) values than normal cells, the lowest being for the DNA-PK-deficient cells, which was near unity. To further

Python Radiative Transfer Emission code (PyRaTE): non-LTE spectral lines simulations

Science.gov (United States)

Tritsis, A.; Yorke, H.; Tassis, K.

2018-05-01

We describe PyRaTE, a new, non-local thermodynamic equilibrium (non-LTE) line radiative transfer code developed specifically for post-processing astrochemical simulations. Population densities are estimated using the escape probability method. When computing the escape probability, the optical depth is calculated towards all directions with density, molecular abundance, temperature and velocity variations all taken into account. A very easy-to-use interface, capable of importing data from simulations outputs performed with all major astrophysical codes, is also developed. The code is written in PYTHON using an "embarrassingly parallel" strategy and can handle all geometries and projection angles. We benchmark the code by comparing our results with those from RADEX (van der Tak et al. 2007) and against analytical solutions and present case studies using hydrochemical simulations. The code will be released for public use.

Benchmark results in radiative transfer

International Nuclear Information System (INIS)

Garcia, R.D.M.; Siewert, C.E.

1986-02-01

Several aspects of the F N method are reported, and the method is used to solve accurately some benchmark problems in radiative transfer in the field of atmospheric physics. The method was modified to solve cases of pure scattering and an improved process was developed for computing the radiation intensity. An algorithms for computing several quantities used in the F N method was done. An improved scheme to evaluate certain integrals relevant to the method is done, and a two-term recursion relation that has proved useful for the numerical evaluation of matrix elements, basic for the method, is given. The methods used to solve the encountered linear algebric equations are discussed, and the numerical results are evaluated. (M.C.K.) [pt

Urethrography and ischial intertuberosity line in radiation therapy planning for prostate carcinoma

International Nuclear Information System (INIS)

Sadeghi, Ahmad; Kuisk, Hans; Tran, Luu; St Royal, Leslie

1996-01-01

We analyzed our urethrography procedure regarding the validity of using the ischial tuberosity line (ITL) as the caudal margin of treatment portals for prostate carcinoma. The distances of the external urethral sphincter and the lowest margin of the opacified urinary bladder were analyzed in one hundred fifteen consecutive urethrograms. None showed the urethral sphincter to be caudal to the ITL. Ten percent of the sphincters were located less than 1.0 cm cephalad to the ITL, yielding inadequate treatment coverage if the ITL was relied on. Arbitrarily considering 2.0 cm or more of the urethral irradiation to be excessive, the use of the ITL would then have resulted in unnecessary normal tissue irradiation of 42.5%. The ITL should not be used as the caudal margin for prostate treatment portals. Variation in sphincter position, as also seen on lateral projections, reveal a need for urethrography as a necessary supplement to computed tomography to plan radiation portals for prostate cancer

Adaptive response to ionizing radiation induced by low doses of gamma rays in human cell lines

International Nuclear Information System (INIS)

Seong, Jinsil; Chang, Ok Suh; Gwi, Eon Kim

1995-01-01

Purpose: The aim of this study was to investigate whether the adaptive response could be induced in human lymphoblastoid cell lines and human tumor cell lines. The time necessary for the expression of the adaptive response was also investigated. Materials and Methods: Three lymphoblastoid cell lines from ataxia telangiectasia (AT) homozygote (GM 1526), AT heterozygote (GM 3382), and normal individual (3402p) and two hepatoma cell lines, Hep G2 and Hep 3B, were used in this study. Experiments were carried out by delivering 0.01 Gy followed by 0.5 Gy of gamma radiation to the exponentially growing cells. The time necessary for the expression of the adaptive response was determined by varying the time interval between the two doses from 1 to 72 h. In some experiments, 3-aminobenzamide, a potent inhibitor of poly (ADP-ribose) polymerase, was added immediately after the 0.5 Gy exposure. The cultures were fixed 30 min (for the G 2 chromatid) and 6 h (for the S chromatid) after the 0.5 Gy exposure. Metaphase chromosome assay was carried out to score chromatid breaks as an end point. Results: A prior exposure to 0.01 Gy of gamma rays significantly reduced the number of chromatid breaks induced by subsequent higher doses (0.5 Gy) in all the tested cell lines. The magnitude of the adaptive response was similar among the cell lines despite their different radiosensitivities. In the G 2 chromatids, the adaptive response was observed both at short-time intervals, as early as 1 h, and at long-time intervals. In the S chromatids, however, the adaptive response was shown only at long-time intervals. When 3-aminobenzamide was added after the 0.5 Gy, the adaptive responses were abolished in all the experimental groups. Conclusion: The adaptive response was observed in human lymphoblastoid cell lines and hepatoma cell lines. The magnitude of the adaptive response did not seem to be related to the radiosensitivity of the cells. The elimination of the adaptive response with 3

Characterization of radiation-induced Apoptosis in rodent cell lines

International Nuclear Information System (INIS)

Guo, Min; Chen, Changhu; Ling, C.C.

1997-01-01

For REC:myc(ch1), Rat1 and Rat1:myc b cells, we determined the events in the development of radiation-induced apoptosis to be in the following order: cell division followed by chromatin condensation, membrane blebbing, loss of adhesion and the uptake of vital dye. Experimental data which were obtained using 4 He ions of well defined energies and which compared the dependence of apoptosis and clonogenic survival on 4 He range strongly suggested that in our cells both apoptosis and loss of clonogenic survival resulted from radiation damage to the cell nucleus. Corroboratory evidence was that BrdU incorporation sensitized these cells to radiation-induced apoptosis. Comparing the dose response for apoptosis and the clonogenic survival curves for Rat1 and Rat1:myc b cells, we concluded that radiation-induced cell inactivation as assayed by clonogenic survival, and that a modified linear-quadratic model, proposed previously, modeled such a contribution effectively. In the same context, the selective increase in radiation-induced apoptosis. Comparing the dose response for apoptosis and the clonogenic survival curves for Rat1 and Rat1:myc b cells, we concluded that radiation-induced apoptosis contributed to the overall radiation-induced cell inactivation as assayed by clonogenic survival, and that a modified linear-quadratic model, proposed previously, modeled such a contribution effectively. In the same context, the selective increase in radiation-induced apoptosis during late S and G 2 phases reduced the relative radioresistance observed for clonogenic survival during late S and G 2 phases. 30 refs., 8 figs

Radiation of planar electromagnetic waves by a line source in anisotropic metamaterials

International Nuclear Information System (INIS)

Cheng Qiang; Jiang Weixiang; Cui Tiejun

2010-01-01

We show experimentally that a line source in an anisotropic metamaterial directly radiates planar electromagnetic waves instead of cylindrical waves, when one component of the permeability tensor approaches zero. The impedance of this material can be perfectly matched to that of free space, which can significantly reduce the reflections between the source and the superstrate, as in traditional highly directive antennas based on zero index metamaterials. Such a unique property determines the two-way propagation of electromagnetic waves excited by a line source, instead of all-way propagation. From this feature, a highly directive emission of electromagnetic waves is achieved using the anisotropic metamaterial with arbitrary shape. We have designed and fabricated the anisotropic metamaterial in the microwave region, and observed the generation of plane waves and their highly directive emission. The proposed plane-wave emission is independent of the shape variance of the anisotropic metamaterial, which can be utilized in the design of conformal antennas.

GAMMA–GAMMA ABSORPTION IN THE BROAD LINE REGION RADIATION FIELDS OF GAMMA-RAY BLAZARS

Energy Technology Data Exchange (ETDEWEB)

Böttcher, Markus; Els, Paul, E-mail: Markus.Bottcher@nwu.ac.za [Centre for Space Research, North-West University, Potchefstroom, 2531 (South Africa)

2016-04-20

The expected level of γγ absorption in the Broad Line Region (BLR) radiation field of γ -ray loud Flat Spectrum Radio Quasars (FSRQs) is evaluated as a function of the location of the γ -ray emission region. This is done self-consistently with parameters inferred from the shape of the spectral energy distribution (SED) in a single-zone leptonic EC-BLR model scenario. We take into account all geometrical effects both in the calculation of the γγ opacity and the normalization of the BLR radiation energy density. As specific examples, we study the FSRQs 3C279 and PKS 1510-089, keeping the BLR radiation energy density at the location of the emission region fixed at the values inferred from the SED. We confirm previous findings that the optical depth due to γγ absorption in the BLR radiation field exceeds unity for both 3C279 and PKS 1510-089 for locations of the γ -ray emission region inside the inner boundary of the BLR. It decreases monotonically, with distance from the central engine and drops below unity for locations within the BLR. For locations outside the BLR, the BLR radiation energy density required for the production of GeV γ -rays rapidly increases beyond observational constraints, thus making the EC-BLR mechanism implausible. Therefore, in order to avoid significant γγ absorption by the BLR radiation field, the γ -ray emission region must therefore be located near the outer boundary of the BLR.

Radiation Detection Center on the Front Lines

International Nuclear Information System (INIS)

Hazi, A

2005-01-01

Many of today's radiation detection tools were developed in the 1960s. For years, the Laboratory's expertise in radiation detection resided mostly within its nuclear test program. When nuclear testing was halted in the 1990s, many of Livermore's radiation detection experts were dispersed to other parts of the Laboratory, including the directorates of Chemistry and Materials Science (CMS); Physics and Advanced Technologies (PAT); Defense and Nuclear Technologies (DNT); and Nonproliferation, Arms Control, and International Security (NAI). The RDC-- was formed to maximize the benefit of radiation detection technologies being developed in 15 to 20 research and development (R and D) programs. These efforts involve more than 200 Laboratory employees across eight directorates, in areas that range from electronics to computer simulations. The RDC's primary focus is the detection, identification, and analysis of nuclear materials and weapons. A newly formed outreach program within the RDC-- is responsible for conducting radiation detection workshops and seminars across the country and for coordinating university student internships. Simon Labov, director of the RDC, says, ''Virtually all of the Laboratory's programs use radiation detection devices in some way. For example, DNT uses radiation detection to create radiographs for their work in stockpile stewardship and in diagnosing explosives; CMS uses it to develop technology for advancing the detection, diagnosis, and treatment of cancer; and the Energy and Environment Directorate uses radiation detection in the Marshall Islands to monitor the aftermath of nuclear testing in the Pacific. In the future, the National Ignition Facility will use radiation detection to probe laser targets and study shock dynamics.''

Characteristics of replication and radiation response of Aedes Albopictus cell line in vitro

International Nuclear Information System (INIS)

Lee, C.K.

1974-01-01

The radiosensitivity of the line of Aedes albopictus cells was investigated by scoring x-ray-induced chromosome aberrations as a function of dose and of time after irradiation as well as the modification by dose fractionation. In order to obtain these data, a series of studies, e.g., karyotype, cell life cycle, radiation- induced mitotic delay, and frequency and type of spontaneous aberrations, were carried out. Cells from this line had three pairs of chromosomes as a stem line chromosome number. The morphology of the chromosomes is metacentric. Somatic pairing between homologous chromosomes was observed as a common event and there was a high frequency of achromatic gaps on the chromosomes. These observations are in good agreement with those made in other laboratories. The generation time of A. albopictus cell line was approximately 32 hours, in which G 1 , S, and G 2 phases were 2 1 / 2 , 24 and 5 1 / 2 hours respectively. This generation time is in agreement with the population doubling time observed in our cell growth studies. By contrast, in most mammalian cells, G 1 usually is the longest phase and S is comparatively short. Dose fractionation studies indicated that A. albopictus cells in culture may have a faster chromosome repair system than mammalian and other cell systems. This may, at least in part; explain the difference in radiosensitivity between A. albopictus cell line and other cell systems. (Diss. Abstr.)

Fibulin-3 negatively regulates ALDH1 via c-MET suppression and increases γ-radiation-induced sensitivity in some pancreatic cancer cell lines

Energy Technology Data Exchange (ETDEWEB)

Kim, In-Gyu, E-mail: igkim@kaeri.re.kr [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, 989-111 Daedeok-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Department of Radiation Biotechnology and Applied Radioisotope, Korea University of Science and Technology (UST), 989-111 Daedeok-daero, Yusong-gu, Daejeon 305-353 (Korea, Republic of); Lee, Jae-Ha [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, 989-111 Daedeok-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Department of Radiation Biotechnology and Applied Radioisotope, Korea University of Science and Technology (UST), 989-111 Daedeok-daero, Yusong-gu, Daejeon 305-353 (Korea, Republic of); Kim, Seo-Yoen; Kim, Jeong-Yul [Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, 989-111 Daedeok-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Cho, Eun-Wie [Epigenomics Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of)

2014-11-21

Highlights: • FBLN-3 gene was poorly expressed in some pancreatic cancer lines. • FBLN-3 promoter region was highly methylated in some pancreatic cancer cell lines. • FBLN-3 inhibited c-MET activation and expression and reduced cellular level of ALDH1. • FBLN-3/c-Met/ALDH1 axis modulates stemness and EMT in pancreatic cancer cells. - Abstract: Fibulin-3 (FBLN-3) has been postulated to be either a tumor suppressor or promoter depending on the cell type, and hypermethylation of the FBLN-3 promoter is often associated with human disease, especially cancer. We report that the promoter region of the FBLN-3 was significantly methylated (>95%) in some pancreatic cancer cell lines and thus FBLN-3 was poorly expressed in pancreatic cancer cell lines such as AsPC-1 and MiaPaCa-2. FBLN-3 overexpression significantly down-regulated the cellular level of c-MET and inhibited hepatocyte growth factor-induced c-MET activation, which were closely associated with γ-radiation resistance of cancer cells. Moreover, we also showed that c-MET suppression or inactivation decreased the cellular level of ALDH1 isozymes (ALDH1A1 or ALDH1A3), which serve as cancer stem cell markers, and subsequently induced inhibition of cell growth in pancreatic cancer cells. Therefore, forced overexpression of FBLN-3 sensitized cells to cytotoxic agents such as γ-radiation and strongly inhibited the stemness and epithelial to mesenchymal transition (EMT) property of pancreatic cancer cells. On the other hand, if FBLN3 was suppressed in FBLN-3-expressing BxPC3 cells, the results were opposite. This study provides the first demonstration that the FBLN-3/c-MET/ALDH1 axis in pancreatic cancer cells partially modulates stemness and EMT as well as sensitization of cells to the detrimental effects of γ-radiation.

Fibulin-3 negatively regulates ALDH1 via c-MET suppression and increases γ-radiation-induced sensitivity in some pancreatic cancer cell lines

International Nuclear Information System (INIS)

Kim, In-Gyu; Lee, Jae-Ha; Kim, Seo-Yoen; Kim, Jeong-Yul; Cho, Eun-Wie

2014-01-01

Highlights: • FBLN-3 gene was poorly expressed in some pancreatic cancer lines. • FBLN-3 promoter region was highly methylated in some pancreatic cancer cell lines. • FBLN-3 inhibited c-MET activation and expression and reduced cellular level of ALDH1. • FBLN-3/c-Met/ALDH1 axis modulates stemness and EMT in pancreatic cancer cells. - Abstract: Fibulin-3 (FBLN-3) has been postulated to be either a tumor suppressor or promoter depending on the cell type, and hypermethylation of the FBLN-3 promoter is often associated with human disease, especially cancer. We report that the promoter region of the FBLN-3 was significantly methylated (>95%) in some pancreatic cancer cell lines and thus FBLN-3 was poorly expressed in pancreatic cancer cell lines such as AsPC-1 and MiaPaCa-2. FBLN-3 overexpression significantly down-regulated the cellular level of c-MET and inhibited hepatocyte growth factor-induced c-MET activation, which were closely associated with γ-radiation resistance of cancer cells. Moreover, we also showed that c-MET suppression or inactivation decreased the cellular level of ALDH1 isozymes (ALDH1A1 or ALDH1A3), which serve as cancer stem cell markers, and subsequently induced inhibition of cell growth in pancreatic cancer cells. Therefore, forced overexpression of FBLN-3 sensitized cells to cytotoxic agents such as γ-radiation and strongly inhibited the stemness and epithelial to mesenchymal transition (EMT) property of pancreatic cancer cells. On the other hand, if FBLN3 was suppressed in FBLN-3-expressing BxPC3 cells, the results were opposite. This study provides the first demonstration that the FBLN-3/c-MET/ALDH1 axis in pancreatic cancer cells partially modulates stemness and EMT as well as sensitization of cells to the detrimental effects of γ-radiation

Measurement of the central ion and electron temperature of tokamak plasmas from the x-ray line radiation of high-Z impurity ions

International Nuclear Information System (INIS)

Bitter, M.; von Goeler, S.; Goldman, M.; Hill, K.W.; Horton, R.; Roney, W.; Sauthoff, N.; Stodiek, W.

1982-04-01

This paper describes measurements of the central ion and electron temperature of tokamak plasmas from the observation of the 1s - 2p resonance lines, and the associated dielectronic (1s 2 nl - 1s2pnl, with n greater than or equal to 2) satellites, of helium-like iron (Fe XXV) and titanium (Ti XXI). The satellite to resonance line ratios are very sensitive to the electron temperature and are used as an electron temperature diagnostic. The ion temperature is deduced from the Doppler width of the 1s - 2p resonance lines. The measurements have been performed with high resolution Bragg crystal spectrometers on the PLT (Princeton Large Torus) and PDX (Poloidal Divertor Experiment) tokamaks. The details of the experimental arrangement and line evaluation are described, and the ion and electron temperature results are compared with those obtained from independent diagnostic techniques, such as the analysis of charge-exchange neutrals and measurements of the electron cyclotron radiation. The obtained experimental results permit a detailed comparison with theoretical predictions

Development of highly polished, grazing incidence mirrors for synchrotron radiation beam lines at SSRL

Energy Technology Data Exchange (ETDEWEB)

Tirsell, K.G.; Berglin, E.J.; Fuchs, B.A.; Holdener, F.R.; Humpal, H.H.; Karpenko, V.P.; Kulkarni, S.; Fantone, S.D.

1987-08-01

New platinum-coated grazing incidence mirrors with low surface roughnesses have been developed to focus bending magnet radiation from the SSRL/SLAC SPEAR storage ring on the entrance slits of two Beam Line VIII grating monochromators. The first mirror in the toroidal grating monochromator (TGM) branch is a cooled SiC cylinder capable of absorbing synchrotron radiation power levels of up to 260 watts without excessive distortion. This mirror deflects the beam vertically through a 12/degree/ angle and focuses it sagitally on the TGM entrance slit plane. The second TGM optical element is a fused-silica spherical mirror with a large radius of curvature that deflects the beam vertically through an additional 12/degree/ and focuses it tangentially with 3/1 demagnification. The first mirror in our spherical grating branch is a 5/degree/-vertically deflecting, cooled SiC toroid designed to focus tangentially on the monochromator entrance slits and sagitally in the exit slits. A 4/degree/-deflecting fused silica mirror is used after the exit sites in each beam line to refocus on to the sample. For this application a thin cylinder is bent to approximate an ellipsoid. The mirrors are now installed at SSRL and performance measurements are planned. Qualitatively the focus of the TGM optics at the entrance slit plane appears very good. In this paper we discuss considerations leading to the choice of SiC for each of the two first mirrors. We present highlights of the development of these mirrors with some emphasis on SiC polishing techniques. In addition, the specialized metrology developed to produce the more difficult figure of the toroid will be described. Measured surface roughness and figure results will be presented. 19 refs., 11 figs.

Development of highly polished, grazing incidence mirrors for synchrotron radiation beam lines at SSRL

International Nuclear Information System (INIS)

Tirsell, K.G.; Berglin, E.J.; Fuchs, B.A.; Holdener, F.R.; Humpal, H.H.; Karpenko, V.P.; Kulkarni, S.; Fantone, S.D.

1987-08-01

New platinum-coated grazing incidence mirrors with low surface roughnesses have been developed to focus bending magnet radiation from the SSRL/SLAC SPEAR storage ring on the entrance slits of two Beam Line VIII grating monochromators. The first mirror in the toroidal grating monochromator (TGM) branch is a cooled SiC cylinder capable of absorbing synchrotron radiation power levels of up to 260 watts without excessive distortion. This mirror deflects the beam vertically through a 12/degree/ angle and focuses it sagitally on the TGM entrance slit plane. The second TGM optical element is a fused-silica spherical mirror with a large radius of curvature that deflects the beam vertically through an additional 12/degree/ and focuses it tangentially with 3/1 demagnification. The first mirror in our spherical grating branch is a 5/degree/-vertically deflecting, cooled SiC toroid designed to focus tangentially on the monochromator entrance slits and sagitally in the exit slits. A 4/degree/-deflecting fused silica mirror is used after the exit sites in each beam line to refocus on to the sample. For this application a thin cylinder is bent to approximate an ellipsoid. The mirrors are now installed at SSRL and performance measurements are planned. Qualitatively the focus of the TGM optics at the entrance slit plane appears very good. In this paper we discuss considerations leading to the choice of SiC for each of the two first mirrors. We present highlights of the development of these mirrors with some emphasis on SiC polishing techniques. In addition, the specialized metrology developed to produce the more difficult figure of the toroid will be described. Measured surface roughness and figure results will be presented. 19 refs., 11 figs

LHCb: Radiation hard programmable delay line for LHCb Calorimeter Upgrade

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Mauricio Ferre, J; Vilasís Cardona, X; Picatoste Olloqui, E; Machefert, F; Lefrançois, J; Duarte, O

2013-01-01

This poster describes the implementation of a SPI-programmable clock delay chip based on a Delay Locked Loop (DLL) in order to shift the phase of the LHC clock (25 ns) in steps of 1ns, with a 4ps jitter and 18ps of DNL. The delay lines will be integrated into ICECAL, the LHCb calorimeter front-end ASIC in the near future. The stringent noise requirements on the ASIC imply minimizing the noise contribution of digital components. This is accomplished by implementing the DLL in differential mode. To achieve the required radiation tolerance several techniques are applied: double guard rings between PMOS and NMOS transistors as well as glitch suppressors and TMR Registers. This 5.7 mm2 chip has been implemented in CMOS 0.35um technology.

Evaluation of apoptosis and apoptosis proteins as possible markers of radiation at doses 0.1-2 Gy, in comparison to the micronucleus assay in three cell lines

International Nuclear Information System (INIS)

Jaworska, A.; Angelis, P. de

1997-01-01

In recent years the interest in apoptosis as possible indicator of radiation damage has increased. Studies have been done to examine the induction of apoptosis after ionizing radiation using morphological criteria, characteristic DNA damage pattern(ladders), early DNA damage using flow cytometry and/or expression of the proteins involved in apoptosis. But the picture which emerges from these investigations is unclear. Some researchers suggest that apoptosis studies can be used as potential assays of biological dosimetry, others doubt if apoptosis can be used as a marker of irradiation at all. Most studies have been done using relatively high doses of radiation. In this study we focus on apoptosis induction after relatively small doses (0,1-2 Gy). We detected apoptosis with the in situ terminal deoxynucleotidyl transferase assay by flow cytometry, and measured the expression of proteins that regulate apoptosis (Bcl-2, Bax, P53) with Western blotting. As comparison we used the cytokinesis-block micronucleus assay as a reference. The studies were carried out in three lymphoid cell lines: the mouse lymphoma L5178Y resistant and sensitive cell lines widely used in radiobiological studies, and the human pre-B cell leukemia Reh cells. Our results indicate that we can not consider the examined parameters of apoptosis as markers of radiation in these cell lines. (author)

Are physicians aware enough of patient radiation protection? Results from a survey among physicians of Pavia District- Italy.

Science.gov (United States)

Campanella, Francesca; Rossi, Laura; Giroletti, Elio; Micheletti, Piero; Buzzi, Fabio; Villani, Simona

2017-06-14

Radiological practices are the first anthropic sources of ionizing radiation exposure of the population. However, a review of recent publications underlines inadequate doctors' knowledge about doses imparted in medical practices and about patient protection that might explain unnecessary radiological prescriptions. We investigated the knowledge of the physicians of Pavia District (Italy) on the risk of radiation exposure. A cross sectional study was performed involving the Medical Association of Pavia District. Data were collected with a self-administered questionnaire, available on-line with private login and password. Four hundred nineteen physicians fulfilled the questionnaire; 48% of participants reported training about radiation protection. The average percentage of correct answers on the knowledge on ionizing radiation was 62.29%, with a significantly higher result between radiologist. Around 5 and 13% of the responders do not know that, respectively, ultrasonography and magnetic resonance do not expose patients to ionizing radiations. Only 5% of the physicians properly identified the cancer risk rate associated to abdomen computed tomography. The findings show a quite good level of the general knowledge about ionizing radiations, higher that reported in literature. Nevertheless, we believe the usefulness of training on the risk linked to radiation exposure in medicine for physicians employed in every area.

Pharmacological manipulation of radiation induced apoptosis in a cervical carcinoma cell line

International Nuclear Information System (INIS)

Kamradt, M.; Mohideen, N.; Krueger, E.; Sokolova, I.A.; Khodarev, N.N; Vaughan, A.T.M.

1997-01-01

Purpose: Radiotherapy is a curative option in the treatment of early stage cervical carcinoma and radioresistant tumors limit local control and survival. Therefore, it is important to understand mechanisms by which cells evade death after irradiation. Of these, the process of apoptosis offers a useful model system to study. Tumors of the cervix offer a unique opportunity in that most contain an HPV genome expressing the E6 and E7 gene products under the control of a glucocorticoid responsive promoter. The HPV E6 and E7 proteins target p53 and/or Rb, both of which are involved in cell cycle control and in the apoptotic process. It was previously determined that treatment with the corticosteroid dexamethasone increased transcription of E6 and E7 and decreased p53 protein levels which corresponded with increased radioresistance and decreased apoptosis in C4-1 cervical carcinoma cells. The goal of this study is to demonstrate pharmacological manipulation of apoptosis within an HPV +ve cervical cell line. Methods: The HPV 18 +ve and p53 wildtype human cervical cell line C4-1 was used in this study. Apoptosis was induced by exposure to 6 Gy of gamma radiation and the ability of cells to undergo apoptosis was determined by morphology and the ability to form internucleosomal fragments using a DNA laddering technique. Cells were exposed to 0.01 to 1 μM dexamethasone in the presence or absence of 1 μM Mifepristone (RU486), a steroid antagonist and analyzed using the DNA laddering assay. In addition, cells that were irradiated in the presence of dexamethasone and/or Mifepristone were collected and p53 protein levels determined by FACS analysis. Results: Apoptosis was observed at a low level in control cells and was increased by irradiation with 6 Gy as determined by DNA laddering and morphology. The presence of 0.01 to 1 μM dexamethasone reduced both the radiation induced DNA laddering and also that seen in control cells. Addition of 1 μM Mifepristone to dexamethasone

Expansion of Collisional Radiative Model for Helium line ratio spectroscopy

Science.gov (United States)

Cinquegrani, David; Cooper, Chris; Forest, Cary; Milhone, Jason; Munoz-Borges, Jorge; Schmitz, Oliver; Unterberg, Ezekial

2015-11-01

Helium line ratio spectroscopy is a powerful technique of active plasma edge spectroscopy. It enables reconstruction of plasma edge parameters like electron density and temperature by use of suitable Collisional Radiative Models (CRM). An established approach is successful at moderate plasma densities (~1018m-3 range) and temperature (30-300eV), taking recombination and charge exchange to be negligible. The goal of this work is to experimentally explore limitations of this approach to CRM. For basic validation the Madison Plasma Dynamo eXperiment (MPDX) will be used. MPDX offers a very uniform plasma and spherical symmetry at low temperature (5-20 eV) and low density (1016 -1017m-3) . Initial data from MPDX shows a deviation in CRM results when compared to Langmuir probe data. This discrepancy points to the importance of recombination effects. The validated model is applied to first time measurement of electron density and temperature in front of an ICRH antenna at the TEXTOR tokamak. These measurements are important to understand RF coupling and PMI physics at the antenna limiters. Work supported in part by start up funds of the Department of Engineering Physics at the UW - Madison, USA and NSF CAREER award PHY-1455210.

Homozygous mutations in the Fhit gene results in resistance to ionizing radiation and inhibition of apoptosis

International Nuclear Information System (INIS)

Turner, B.C.; Potoczek, M.B.; Ottey, M.; Croce, C.M.; Huebner, K.

2001-01-01

Purpose: The Fhit gene was identified because it represents the most active constitutive chromosome fragile site and has functions often associated with a tumor suppressor gene. Mutations in the Fhit locus have been identified in many cancer-derived cell lines, primary human tumors including lung, head and neck, colon, breast, and esophagus, and are associated with tobacco-induced lung cancers. In this study, we examined the cellular response of mouse epithelial cells with complete loss of Fhit to therapeutic doses of ionizing radiation and the prognostic importance of Fhit protein in early stage breast cancer patients treated with breast conserving therapy. Materials and Methods: Mouse epithelial cell lines containing either homozygous mutant Fhit -/- or wild-type Fhit +/+ were derived from mice (C57BL/6J X 129/SvJ) with either wild-type or inactivated Fhit gene. Clonogenic cell survival assays were carried out on subconfluent cells in logarithmic growth using a 137 Cs irradiator and survival curves were plotted as the log of the surviving cells versus dose and corrected for cloning efficiency. Apoptosis following ionizing radiation was determined by flow cytometry using the Annexin-V FITC kit and DAPI staining. Paraffin-embedded breast tumor blocks were obtained from 42 women with local breast tumor recurrence and 42 matched breast cancer patients without local cancer relapse treated with breast conserving therapy and stained with a 1:4000 dilution of polyclonal antibody to the Fhit protein and scored based on both intensity and distribution of Fhit staining within the invasive breast cancer component. Results: Treatment of Fhit -/- mouse epithelial cells with single fraction doses of ionizing radiation including 2, 4, 6, and 10 Gy result in 4-6 fold increase in cellular survival compared with isogenic parental cells from Fhit +/+ mice. Fhit -/- epithelial cells displayed 3-5 fold lower levels of apoptosis in response to both low and high doses of ionizing

Radiosensitivity of mesothelioma cell lines

International Nuclear Information System (INIS)

Haekkinen, A.M.; Laasonen, A.; Linnainmaa, K.; Mattson, K.; Pyrhoenen, S.

1996-01-01

The present study was carried out in order to examine the radiosensitivity of malignant pleural mesothelioma cell lines. Cell kinetics, radiation-induced delay of the cell cycle and DNA ploidy of the cell lines were also determined. For comparison an HeLa and a human foetal fibroblast cell line were simultaneously explored. Six previously cytogenetically and histologically characterized mesothelioma tumor cell lines were applied. A rapid tiazolyl blue microtiter (MTT) assay was used to analyze radiosensitivity and cell kinetics and DNA ploidy of the cultured cells were determined by flow cytometry. The survival fraction after a dose of 2 Gy (SF2), parameters α and β of the linear quadratic model (LQ-model) and mean inactivation dose (D MID ) were also estimated. The DNA index of four cell lines equaled 1.0 and two cell lines equaled 1.5 and 1.6. Different mesothelioma cell lines showed a great variation in radiosensitivity. Mean survival fraction after a radiation dose of 2 Gy (SF2) was 0.60 and ranged from 0.36 to 0.81 and mean α value was 0.26 (range 0.48-0.083). The SF2 of the most sensitive diploid mesothelioma cell line was 0.36: Less than that of the foetal fibroblast cell line (0.49). The survival fractions (0.81 and 0.74) of the two most resistant cell lines, which also were aneuploid, were equal to that of the HeLa cell line (0.78). The α/β ratios of the most sensitive cell lines were almost an order of magnitude greater than those of the two most resistant cell lines. Radiation-induced delay of the most resistant aneuploid cell line was similar to that of HeLa cells but in the most sensitive (diploid cells) there was practically no entry into the G1 phase following the 2 Gy radiation dose during 36 h. (orig.)

Radiosensitivity of mesothelioma cell lines

Energy Technology Data Exchange (ETDEWEB)

Haekkinen, A.M. [Dept. of Oncology, Univ. Central Hospital, Helsinki (Finland); Laasonen, A. [Dept. of Pathology, Central Hospital of Etelae-Pohjanmaa, Seinaejoki (Finland); Linnainmaa, K. [Dept. of Industrial Hygiene and Toxicology, Inst. of Occupational Health, Helsinki (Finland); Mattson, K. [Dept. Pulmonary Medicine, Univ. Central Hospital, Helsinki (Finland); Pyrhoenen, S. [Dept. of Oncology, Univ. Central Hospital, Helsinki (Finland)

1996-10-01

The present study was carried out in order to examine the radiosensitivity of malignant pleural mesothelioma cell lines. Cell kinetics, radiation-induced delay of the cell cycle and DNA ploidy of the cell lines were also determined. For comparison an HeLa and a human foetal fibroblast cell line were simultaneously explored. Six previously cytogenetically and histologically characterized mesothelioma tumor cell lines were applied. A rapid tiazolyl blue microtiter (MTT) assay was used to analyze radiosensitivity and cell kinetics and DNA ploidy of the cultured cells were determined by flow cytometry. The survival fraction after a dose of 2 Gy (SF2), parameters {alpha} and {beta} of the linear quadratic model (LQ-model) and mean inactivation dose (D{sub MID}) were also estimated. The DNA index of four cell lines equaled 1.0 and two cell lines equaled 1.5 and 1.6. Different mesothelioma cell lines showed a great variation in radiosensitivity. Mean survival fraction after a radiation dose of 2 Gy (SF2) was 0.60 and ranged from 0.36 to 0.81 and mean {alpha} value was 0.26 (range 0.48-0.083). The SF2 of the most sensitive diploid mesothelioma cell line was 0.36: Less than that of the foetal fibroblast cell line (0.49). The survival fractions (0.81 and 0.74) of the two most resistant cell lines, which also were aneuploid, were equal to that of the HeLa cell line (0.78). The {alpha}/{beta} ratios of the most sensitive cell lines were almost an order of magnitude greater than those of the two most resistant cell lines. Radiation-induced delay of the most resistant aneuploid cell line was similar to that of HeLa cells but in the most sensitive (diploid cells) there was practically no entry into the G1 phase following the 2 Gy radiation dose during 36 h. (orig.).

Upregulation of HPV E6 and E7 genes in human cervix carcinoma cell lines leads to both an increase in radiation resistance and alterations in apoptosis

International Nuclear Information System (INIS)

Kamradt, M.; Krueger, E.; McCall, A.; Manker, C.; Rudnick, S.; Erlich, E.; Khodarev, N; Vaughan, A.T.M.

1996-01-01

Purpose: Stage I-III cervical cancer is commonly treated with external beam radiotherapy with curative intent. We have shown that the presence of the artificial steroid dexamethasone can increase the radiation resistance of HPV+ve cervical tumors. Dexamethasone treatment enhances cell proliferation by upregulation of HPV 18 E6 and E7 genes through a glucocorticoid responsive element within the HPV promoter region. The goal of this study is to understand the mechanism whereby steroid treatment produces enhanced radioresistance in cervical tumors. Methods: Four cervical tumor cell lines and one squamous carcinoma cell line (SQ-20B) were used. Each cell line was exposed to 0 - 8 Gy of gamma irradiation in the presence or absence of 1 μM dexamethasone (Dx) and assayed for cell survival using a clonogenic assay. Parallel samples were examined by fluorescence microscopy after Triton X-100 permeabilization and propidium iodide staining 1, 2 and 4 days post irradiation. Nuclei containing the characteristic multi-lobular structure and condensed appearance of apoptosis were recorded. To confirm the presence of apoptosis in these cells a terminal deoxynucleotide transferase staining reaction was carried out to label the free DNA ends characteristic of apoptosis. Results: Administration of Dx increased radiation resistance in all HPV+ve E6 and E7 expressing cell lines studied, a similar effect was seen in two additional HPV 18+ve cervical carcinoma cell lines ME180 and MS751 (data not shown). No effect was seen in the HPV-ve cell lines, or C41 K6 containing anti-sense E6 and E7 genes. Introduction of the anti-sense E6 and E7 sequences into C41 did not affect their ability to undergo radiation-induced apoptosis though Dx administration reduced the amount of apoptosis seen. Conversely, Dx treatment of the HeLa cell line increased radioresistance but did not affect the ability of these cells to engage apoptosis. Conclusion: All (5) cervical cell lines studied containing HPV 18

Radiation up-regulated the expression of VEGF in a canine oral melanoma cell line

International Nuclear Information System (INIS)

Flickinger, I.; Rütgen, B.C.; Gerner, W.; Tichy, A.; Saalmüller, A.; Kleiter, M.; Calice, I.

2013-01-01

To evaluate radiosensitivity and the effects of radiation on the expression of vascular endothelial growth factor (VEGF) and VEGF receptors in the canine oral melanoma cell line, TLM 1, cells were irradiated with doses of 0, 2, 4, 6, 8 and 10 Gray (Gy). Survival rates were then determined by a MTT assay, while vascular endothelial growth factor receptor (VEGFR)-1 and -2 expression was measured by flow cytometry and apoptotic cell death rates were investigated using an Annexin assay. Additionally, a commercially available canine VEGF ELISA kit was used to measure VEGF. Radiosensitivity was detected in TLM 1 cells, and mitotic and apoptotic cell death was found to occur in a radiation dose dependent manner. VEGF was secreted constitutively and significant up-regulation was observed in the 8 and 10 Gy irradiated cells. In addition, a minor portion of TLM 1 cells expressed vascular endothelial growth factor receptor (VEGFR)-1 intracellularly. VEGFR-2 was detected in the cytoplasm and was down-regulated following radiation with increasing dosages. In TLM 1 cells, apoptosis plays an important role in radiation induced cell death. It has also been suggested that the significantly higher VEGF production in the 8 and 10 Gy group could lead to tumour resistance. (author)

Adaptive Response to ionizing Radiation Induced by Low Doses of Gamma Rays in Human Lymphoblastoid Cell Lines

International Nuclear Information System (INIS)

Seong, Jin Sil; Suh, Chang Ok; Kim, Gwi Eon

1994-01-01

When cells are exposed to low doses of a mutagenic or clastogenic agents, they often become less sensitive to the effects of a higher does administered subsequently. Such adaptive responses were first described in Escherichia coli and mammalian cells to low doses of an alkylating agent. Since most of the studies have been carried out with human lymphocytes, it is urgently necessary to study this effect in different cellular systems. Its relation with inherent cellular radiosensitivity and underlying mechanism also remain to be answered. In this study, adaptive response by 1 cGy of gamma rays was investigated in three human lymphoblastoid cell lines which were derived from ataxia telangiectasia homozygote, ataxia telangiectasia heterozygote, and normal individual. Experiments were carried out by delivering 1 cGy followed by 50 cGy of gamma radiation and chromatid breaks were scored as an endpoint. The results indicate that prior exposure to 1 cGy of gamma rays reduces the number of chromatid breaks induced by subsequent higher does (50 cGy). The expression of this adaptive response was similar among three cell lines despite of their different radiosensitivity. When 3-aminobenzamide, an inhibitor of poly (ADP-ribose) polymerase, was added after 50 cGy, adaptive responses were abolished in all the tested cell lines. Therefore it is suggested that the adaptive response can be observed in human lymphoblastoid cell lines. Which was first documented through this study. The expression of adaptive response was similar among the cell lines regardless of their radiosensitivity. The elimination of the adaptive response by 3-aminobenzamide is consistent with the proposal that this adaptive response is the result of the induction of a certain chromosomal repair mechanism

TERRA Expression Levels Do Not Correlate With Telomere Length and Radiation Sensitivity in Human Cancer Cell Lines

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Alexandra eSmirnova

2013-05-01

Full Text Available Mammalian telomeres are transcribed into long non-coding telomeric RNA molecules (TERRA that seem to play a role in the maintenance of telomere stability. In human cells, CpG island promoters drive TERRA transcription and are regulated by methylation. It was suggested that the amount of TERRA may be related to telomere length. To test this hypothesis we measured telomere length and TERRA levels in single clones isolated from five human cell lines: HeLa (cervical carcinoma, BRC-230 (breast cancer, AKG and GK2 (gastric cancers and GM847 (SV40 immortalized skin fibroblasts. We observed great clonal heterogeneity both in TRF (Terminal Restriction Fragment length and in TERRA levels. However, these two parameters did not correlate with each other. Moreover, cell survival to γ-rays did not show a significant variation among the clones, suggesting that, in this cellular system, the intra-population variability in telomere length and TERRA levels does not influence sensitivity to ionizing radiation. This conclusion was supported by the observation that in a cell line in which telomeres were greatly elongated by the ectopic expression of telomerase, TERRA expression levels and radiation sensitivity were similar to the parental HeLa cell line.

Living with radiation

International Nuclear Information System (INIS)

Tymen, G.

1999-01-01

This editorial article discusses the various forms of radiation that we live with. In particular, the general public's lack of knowledge on the subject is mentioned and the concentration of the media on radiation accidents and emissions is looked at critically. The various forms of radiation - ionising and non-ionising - are briefly discussed. Natural ionising radiation sources and in particular radon are described and the increasing proportion of doses attributed to cosmic radiation met in high-flying aircraft and radiation doses resulting from medical examination and treatment are discussed. Non-ionising radiation such as electromagnetic fields generated by power lines, mobile telephones and kitchen equipment and their implications on health are also looked at

Correlation between cell survival and DNA single-strand break repair proficiency in the Chinese hamster ovary cell lines AA8 and EM9 irradiated with 365-nm ultraviolet-A radiation

Energy Technology Data Exchange (ETDEWEB)

Churchill, M.E.; Peak, J.G.; Peak, M.J. (Argonne National Lab., IL (USA))

1991-02-01

Cell survival parameters and the induction and repair of DNA single-strand breaks were measured in two Chinese hamster ovary cell lines after irradiation with monochromatic UVA radiation of wavelength 365 nm. The radiosensitive mutant cell line EM9 is known to repair ionizing-radiation-induced single-strand breaks (SSB) more slowly than the parent line AA8. EM9 was determined to be 1.7-fold more sensitive to killing by 365-nm radiation than AA8 at the 10% survival level, and EM9 had a smaller shoulder region on the survival curve ({alpha} = 1.76) than AA8 ({alpha} = 0.62). No significant differences were found between the cell lines in the initial yields of SSB induced either by {gamma}-radiation (as determined by alkaline sucrose gradient sedimentation) or by 365-nm UVA (as determined by alkaline elution). For measurement of initial SSB, cells were irradiated at 0.5{sup o}C to minimize DNA repair processes. Rejoining of 365-nm induced SSB was measured by irradiating cells at 0.5{sup o}C, allowing them to repair at 37{sup o}C in full culture medium, and then quantitating the remaining SSB by alkaline elution. The repair of these breaks followed biphasic kinetics in both cell lines. EM9 repaired the breaks more slowly (T{sub 1/2} values of 1.3 and 61.3 min) than did AA8 (T{sub 1/2} values of 0.9 and 53.3 min), and EM9 also left more breaks unrepaired 90 min after irradiation (24% vs 8% for AA8). Thus, the sensitivity of EM9 to 365-nm radiation correlated with its deficiency in repairing DNA lesions revealed as SSB in alkaline elution. These results suggest that DNA may be a critical target in 365-nm induced cellular lethality and that the ability of AA8 and EM9 cells to repair DNA strand breaks may be related to their ability to survive 365-nm radiation. (author).

Experimental verification for in vitro technique confirmation of bystander effect induced by gamma radiation in CHO-K1 cell line

International Nuclear Information System (INIS)

Viana, P.H.L.; Goes, A.M.; Gomes, D.A.

2013-01-01

The bystander effect refers to biological responses detected in cells not directly irradiated but influenced, somehow, by signals transmitted from neighboring irradiated cells. These biological responses include sister chromatid exchange, mutations, micronucleus formation, chromosomal aberrations, carcinogenesis, apoptosis and necrosis. Although its existence is unquestionable, the mechanisms involved on triggering the bystander effect are not yet completely elucidated. Previous studies have shown that the bystander effect depends on a large variety of parameters including the radiation dose, the dose rate, the type of radiation and type of cells or tissue. This study aims to confirm the technique previously used in the literature in human cell lines for the bystander effect verification. The results suggest that the working conditions adopted by the group show technical efficiency and enables the reproduction of the bystander effect. (author)

Radiation-induced apoptosis and cell cycle checkpoints in human colorectal tumour cell lines

International Nuclear Information System (INIS)

Playle, L.C.

2001-03-01

The p53 tumour suppressor gene is mutated in 75% of colorectal carcinomas and is critical for DNA damage-induced G1 cell cycle arrest. Data presented in this thesis demonstrate that after treatment with Ionizing Radiation (IR), colorectal tumour cell lines with mutant p53 are unable to arrest at G1 and undergo cell cycle arrest at G2. The staurosporine derivative, UCN-01, was shown to abrogate the IR-induced G2 checkpoint in colorectal tumour cell lines. Furthermore, in some cell lines, abrogation of the G2 checkpoint was associated with radiosensitisation. Data presented in this study demonstrate that 2 out of 5 cell lines with mutant p53 were sensitised to IR by UCN-01. In order to determine whether radiosensitisation correlated with lack of functional p53, transfected derivatives of an adenoma-derived cell line were studied, in which endogenous wild type p53 was disrupted by expression of a dominant negative p53 mutant protein (and with a vector control). In both these cell lines UCN-01 abrogated the G2 arrest however this was not associated with radiosensitisation, indicating that radiosensitisation is a cell type-specific phenomenon. Although 2 colorectal carcinoma cell lines, with mutant p53, were sensitised to IR by UCN-01, the mechanisms of p53-independent IR-induced apoptosis in the colon are essentially unknown. The mitogen-activated protein kinase (MAPK) pathways (that is the JNK, p38 and ERK pathways) have been implicated in apoptosis in a range of cell systems and in IR-induced apoptosis in some cell types. Data presented in this study show that, although the MAPKs can be activated by the known activator anisomycin, there is no evidence of a role for MAPKs in IR-induced apoptosis in colorectal tumour cell lines, regardless of p53 status. In summary, some colorectal tumour cell lines with mutant p53 can be sensitised to IR-induced cell death by G2 checkpoint abrogation and this may be an important treatment strategy, however mechanisms of IR-induced p53

Isoeffect lines using TDF and CRE concepts

International Nuclear Information System (INIS)

Supe, S.J.; Sasane, J.B.; Supe, D.S.

1980-01-01

Isoeffect lines based on Ellis' Nominal Standard Dose concept, Orton's Time Dose and Fractionation Factor (TDF) concept, and Kirk et al's Cumulative Radiation Effect (CRE) concept give differing results of treatment planning. Experience with isoeffect lines based on the above concepts in planning in case of radiotherapy for carcinoma of bladder and carcinoma of uterine cervix is narrated. (M.G.B.)

In vitro radiation studies on Ewing's sarcoma cell lines and human bone marrow: application to the clinical use of total body irradiation (TBI)

International Nuclear Information System (INIS)

Kinsella, T.J.; Mitchell, J.B.; McPherson, S.; Miser, J.; Triche, T.; Glatstein, E.

1984-01-01

Patients with Ewing's sarcoma who present with a central axis or proximal extremity primary and/or with metastatic disease have a poor prognosis despite aggressive combination chemotherapy and local irradiation. In this high risk group of patients, total body irradiation (TBI) has been proposed as a systemic adjuvant. To aid in the design of a clinical TBI protocol, the authors have studied in the in vitro radiation response of two established cell lines of Ewing's sarcoma and human bone marrow CFUc. The Ewing's lines showed a larger D 0 and anti-n compared to the bone marrow CFU. No repair of potentially lethal radiation damage (PLDR) was found after 4.5 Gy in plateau phase Ewing's sarcoma cells. A theoretical split dose survival curve for both the Ewing's sarcoma lines and human bone marrow CFUc using this TBI schedule shows a significantly lower surviving fraction (10 -4 -10 -5 ) for the bone marrow CFUc. Based on these in vitro results, two 4.0 Gy fractions separated by 24 hours is proposed as the TBI regimen. Because of the potentially irreversible damage to bone marrow, autologous bone marrow transplantation following the TBI is felt to be necessary. The details of this clinical protocol in high risk Ewing's sarcoma patients are outlined

An empirical line-by-line model for the infrared solar transmittance spectrum from 700 to 5000cm{sup -1}

Energy Technology Data Exchange (ETDEWEB)

Hase, F. [Institut fuer Meteorologie und Klimaforschung, Forschungszentrum Karlsruhe, Postfach 3640, D-76021 Karlsruhe (Germany)]. E-mail: frank.hase@imk.fzk.de; Demoulin, P. [Institut d' Astrophysique et de Geophysique, allee du VI aout, 17, batiment B5a, B-4000, Liege (Belgium); Sauval, A.J. [Observatoire Royal de Belgique, avenue circulaire, 3, B-1180, Bruxelles (Belgium); Toon, G.C. [Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Bernath, P.F. [Department of Chemistry, University of Waterloo, Waterloo, Ont., Canada N2L3G1 (Canada); Goldman, A. [Department of Physics, University of Denver, Denver, CO 80208 (United States); Hannigan, J.W. [Atmospheric Chemistry Division, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80303 (United States); Rinsland, C.P. [NASA Langley Research Center, Hampton, VA 23681-2199 (United States)

2006-12-15

An empirical line-by-line model for the infrared solar transmittance spectrum is presented. The model can be incorporated into radiative transfer codes to allow fast calculation of all relevant emission and absorption features in the solar spectrum in the mid-infrared region from 700 to 5000cm{sup -1}. The transmittance is modelled as a function of the diameter of the field-of-view centered on the solar disk: the line broadening due to solar rotation as well as center-to-limb variations in strength and width are taken into account for stronger lines. Applications of the model presented here are in the fields of terrestrial remote sensing in the mid-infrared spectral region when the sun is used as radiation source or scattered solar radiation contributes to the measured signal and in the fields of atmospheric radiative transfer algorithms which compute the propagation of infrared solar radiation in the terrestrial atmosphere.

gamma. radiation of ionium

Energy Technology Data Exchange (ETDEWEB)

Curie, I

1948-12-08

Following the work of Ward (Proc Cambridge Phil Soc 35 322(1939)), the ..gamma..-radiation of ionium (from an IoTh preparation) was studied with the aid of Ta and W screens, and an aluminum counter. The screen measurements confirmed Ward's findings of two radiations, of 68 keV and of about 200 keV. The number of quanta per second of each radiation was determined with the counter, which has been calibrated on certain L lines of radium. The global quanta number of L lines of ionium was also determined. The results were as follows: 0.7 quanta ..gamma.. of 68 keV for 100 ..cap alpha..-particles; 0.2 quanta ..gamma.. of 200 keV for 100 ..cap alpha..-particles; 10 quanta L for 100 ..cap alpha..-particles. These data, which show an important internal conversion, agree with the findings of Teillac (Compt Rend 227 1227 (1948)), who investigated the ..beta..-radiation of ionium. It is the radiation 68 keV which is highly converted. On the other hand, these results do no agree with the data on the fine structure of ionium found by Rosenblum, Valadares, and Vial (Compt Rend 227 1088(1948)).

RRTM: A rapid radiative transfer model

Energy Technology Data Exchange (ETDEWEB)

Mlawer, E.J.; Taubman, S.J.; Clough, S.A. [Atmospheric and Environmental Research, Inc., Cambridge, MA (United States)

1996-04-01

A rapid radiative transfer model (RRTM) for the calculation of longwave clear-sky fluxes and cooling rates has been developed. The model, which uses the correlated-k method, is both accurate and computationally fast. The foundation for RRTM is the line-by-line radiative transfer model (LBLRTM) from which the relevant k-distributions are obtained. LBLRTM, which has been extensively validated against spectral observations e.g., the high-resolution sounder and the Atmospheric Emitted Radiance Interferometer, is used to validate the flux and cooling rate results from RRTM. Validations of RRTM`s results have been performed for the tropical, midlatitude summer, and midlatitude winter atmospheres, as well as for the four Intercomparison of Radiation Codes in Climate Models (ICRCCM) cases from the Spectral Radiance Experiment (SPECTRE). Details of some of these validations are presented below. RRTM has the identical atmospheric input module as LBLRTM, facilitating intercomparisons with LBLRTM and application of the model at the Atmospheric Radiation Measurement Cloud and Radiation Testbed sites.

Field line mapping results in the CNT stellarator

International Nuclear Information System (INIS)

Sarasola, X.; Pedersen, T. Sunn; Kremer, J.P.; Lefrancois, R.G.; Marksteiner, Q.; Ahmad, N.

2005-01-01

The Columbia Non-neutral Torus (CNT), located at Columbia University, is a toroidal, ultra-high vacuum stellarator designed to confine pure electron and other non-neutral plasmas. Its coil configuration is the simplest of any stellarator constructed, since it consists only of two pairs of circular planar copper coils. CNT started operation in November 2004. During its first months of operation a detailed mapping of the nested magnetic surfaces has been developed using the fluorescent method. An electron beam was emitted along a field line by a small moveable electron gun. Different beam energies (ranging from 50 to 200 eV) were used to perform the field line mapping. The e- beam emitted by the electron gun followed the field lines around the torus and hit two moveable ZnO coated aluminum rods that emit visible light when struck by the e-beam. For each position of the e- gun, the phosphor rods scanned the cross-section of the torus allowing a standard digital camera to record a single magnetic surface in a five second exposure. Multiple photos were taken and then manipulated and superposed using IDL software to create composite images of the nested magnetic surfaces. Detailed mapping of the magnetic flux surfaces was completed at a variety of magnetic configurations and at pressures in the 10 -8 Torr range. The experimental results were compared with numerical calculations demonstrating that the obtained measurements agree very well with numerical predictions. In particular, the current configuration has an ultralow aspect ratio (A≤ 1.9) and excellent magnetic surface quality with no detectable island structures or stochastic regions, except at the edge of the plasma where a predicted island chain is present. These experimental results will be presented along with details of the field line mapping system. (author)

Tumourigenicity and radiation resistance of mesenchymal stem cells

DEFF Research Database (Denmark)

D'Andrea, Filippo Peder; Horsman, Michael Robert; Kassem, Moustapha

2012-01-01

Background. Cancer stem cells are believed to be more radiation resistant than differentiated tumour cells of the same origin. It is not known, however, whether normal nontransformed adult stem cells share the same radioresistance as their cancerous counterpart. Material and methods....... Nontumourigenic (TERT4) and tumourigenic (TRET20) cell lines, from an immortalised mesenchymal stem cell line, were grown in culture prior to irradiation and gene expression analysis. Radiation resistance was measured using a clonogenic assay. Differences in gene expression between the two cell lines, both under...... the intercellular matrix. These results also indicate that cancer stem cells are more radiation resistant than stem cells of the same origin....

X-ray emission lines from photoionized plasmas

International Nuclear Information System (INIS)

Liedahl, D.A.

1992-11-01

Plasma emission codes have become a standard tool for the analysis of spectroscopic data from cosmic X-ray sources. However, the assumption of collisional equilibrium, typically invoked in these codes, renders them inapplicable to many important astrophysical situations, particularly those involving X-ray photoionized nebulae, which are likely to exist in the circumsource environments of compact X-ray sources. X-ray line production in a photoionized plasma is primarily the result of radiative cascades following recombination. Through the development of atomic models of several highly-charged ions, this work extends the range of applicability of discrete spectral models to plasmas dominated by recombination. Assuming that ambient plasma conditions lie in the temperature range 10 5 --10 6 K and the density range 10 11 --10 16 cm -3 , X-ray line spectra are calculated over the wavelength range 5--45 angstrom using the HULLAC atomic physics package. Most of the work focuses on the Fe L-shell ions. Line ratios of the form (3s-2p)/(3d-2p) are shown to characterize the principal mode of line excitation, thereby providing a simple signature of photoionization. At electron densities exceeding 10 12 cm -3 , metastable state populations in the ground configurations approach their LTE value, resulting in the enrichment of the Fe L-shell recombination spectrum and a set of density-sensitive X-ray line ratios. Radiative recombination continua and emission lines produced selectively by Δn = 0 dielectronic recombination are shown to provide two classes of temperature diagnostics. Because of the extreme overionization, the recombination continua are expected to be narrow (ΔE/E much-lt 1), with ΔE = kT. Dielectronic recombination selectively drives radiative transitions that originate on states with vacancies in the 2s subshell, states that are inaccessible under pure RR population kinetics

Measurements of downwelling far-infrared radiance during the RHUBC-II campaign at Cerro Toco, Chile and comparisons with line-by-line radiative transfer calculations

Science.gov (United States)

Mast, Jeffrey C.; Mlynczak, Martin G.; Cageao, Richard P.; Kratz, David P.; Latvakoski, Harri; Johnson, David G.; Turner, David D.; Mlawer, Eli J.

2017-09-01

Downwelling radiances at the Earth's surface measured by the Far-Infrared Spectroscopy of the Troposphere (FIRST) instrument in an environment with integrated precipitable water (IPW) as low as 0.03 cm are compared with calculated spectra in the far-infrared and mid-infrared. FIRST (a Fourier transform spectrometer) was deployed from August through October 2009 at 5.38 km MSL on Cerro Toco, a mountain in the Atacama Desert of Chile. There FIRST took part in the Radiative Heating in Unexplored Bands Campaign Part 2 (RHUBC-II), the goal of which is the assessment of water vapor spectroscopy. Radiosonde water vapor and temperature vertical profiles are input into the Atmospheric and Environmental Research (AER) Line-by-Line Radiative Transfer Model (LBLRTM) to compute modeled radiances. The LBLRTM minus FIRST residual spectrum is calculated to assess agreement. Uncertainties (1-σ) in both the measured and modeled radiances are also determined. Measured and modeled radiances nearly all agree to within combined (total) uncertainties. Features exceeding uncertainties can be corrected into the combined uncertainty by increasing water vapor and model continuum absorption, however this may not be necessary due to 1-σ uncertainties (68% confidence). Furthermore, the uncertainty in the measurement-model residual is very large and no additional information on the adequacy of current water vapor spectral line or continuum absorption parameters may be derived. Similar future experiments in similarly cold and dry environments will require absolute accuracy of 0.1% of a 273 K blackbody in radiance and water vapor accuracy of ∼3% in the profile layers contributing to downwelling radiance at the surface.

An experimental study on the low-dose radiosensitivity of tumor cell lines

International Nuclear Information System (INIS)

Kim, Min Sook; Koh, Kwang Joon

1994-01-01

The purpose of this study was to aid in the radiation therapy of head and neck cancer patients. For this study, radiation survival curves were generated for B16, MG-63 and YAC-1 cell lines using semiautomated MTT assay and Dye Exclusion Assay. Irradiation of 2, 4, 6, 8, 10 Gy were delivered at room temperature at a dose rate of 210.2 cGy/min using 60 COγ-ray irradiator ALDORADO 8. The viable cells were determined for each radiation dose and compared to control values. The obtained results were as follows: 1. The was significantly different absorbance at 10 Gy on B16 cell line in MTT assay (P<0.05). 2. There was significantly different absorbance at 4, 6, 8, 10 Gy on MG-63 cell line in MTT assay (P<0.05). 3. YAC-1 cell line was more sensitive than B16 or MG-63 cell line to all doses of radiation (P<0.05). 4. There was significantly different absorbance among all tumor cell lines except between B16 and MG-63 cell line at 2 Gy in MTT assay (P<0.05). 5. Good correlation was obtained between MTT assay and DEA (P<0.05). The efficient of correlation of B16, MG-63 and YAC-1 cell line was 0.845-0.824 and 0.906, respectively.

Time-dependent scattering in resonance lines

International Nuclear Information System (INIS)

Kunasz, P.B.

1983-01-01

A numerical finite-difference method is presented for the problem of time-dependent line transfer in a finite slab in which material density is sufficiently low that the time of flight between scatterings greatly exceeds the relaxation time of the upper state of the scattering transition. The medium is assumed to scatter photons isotropically, with complete frequency redistribution. Numerical solutions are presented for a homogeneous, time-independent slab illuminated by an externally imposed radiation field which enters the slab at t = 0. Graphical results illustrate relaxation to steady state of trapped internal radiation, emergent energy, and emergent profiles. A review of the literature is also given in which the time-dependent line transfer problem is discussed in the context of recent analytical work

Power line harmonic radiation observed by the DEMETER spacecraft at 50/60Hz and low harmonics

Czech Academy of Sciences Publication Activity Database

Němec, F.; Parrot, M.; Santolík, Ondřej

2015-01-01

Roč. 120, č. 10 (2015), s. 8954-8967 ISSN 2169-9380 R&D Projects: GA ČR(CZ) GA14-31899S; GA MŠk LH12231 Institutional support: RVO:68378289 Keywords : PLHR * power line harmonic radiation * DEMETER Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.318, year: 2015 http://onlinelibrary.wiley.com/doi/10.1002/2015JA021682/full

Cell lines derived from a Medaka radiation-sensitive mutant have defects in DNA double-strand break responses

International Nuclear Information System (INIS)

Hidaka, Masayuki; Oda, Shoji; Mitani, Hiroshi; Kuwahara, Yoshikazu; Fukumoto, Manabu

2010-01-01

It was reported that the radiation-sensitive Medaka mutant 'ric1' has a defect in the repair of DNA double-strand breaks (DSBs) induced by γ-rays during early embryogenesis. To study the cellular response of a ric1 mutant to ionizing radiation (IR), we established the mutant embryonic cell lines RIC1-e9, RIC1-e42, RIC1-e43. Following exposure to γ-irradiation, the DSBs in wild-type cells were repaired within 1 h, while those in RIC1 cells were not rejoined even after 2 h. Cell death was induced in the wild-type cells with cell fragmentation, but only a small proportion of the RIC1 cells underwent cell death, and without cell fragmentation. Although both wild-type and RIC1 cells showed mitotic inhibition immediately after γ-irradiation, cell division was much slower to resume in the wild-type cells (20 h versus 12 h). In both wild-type and RIC1 cells, Ser139 phosphorylated H2AX (γH2AX) foci were formed after γ-irradiation, however, the γH2AX foci disappeared more quickly in the RIC1 cell lines. These results suggest that the instability of γH2AX foci in RIC1 cells cause an aberration of the DNA damage response. As RIC1 cultured cells showed similar defective DNA repair as ric1 embryos and RIC1 cells revealed defective cell death and cell cycle checkpoint, they are useful for investigating DNA damage responses in vitro. (author)

High peak current operation of x-ray free-electron laser multiple beam lines by suppressing coherent synchrotron radiation effects

Science.gov (United States)

Hara, Toru; Kondo, Chikara; Inagaki, Takahiro; Togawa, Kazuaki; Fukami, Kenji; Nakazawa, Shingo; Hasegawa, Taichi; Morimoto, Osamu; Yoshioka, Masamichi; Maesaka, Hirokazu; Otake, Yuji; Tanaka, Hitoshi

2018-04-01

The parallel operation of multiple beam lines is an important means to expand the opportunity of user experiments at x-ray free-electron laser (XFEL) facilities. At SPring-8 Angstrom free-electron laser (SACLA), the multi-beam-line operation had been tested using two beam lines, but transverse coherent synchrotron radiation (CSR) effects at a dogleg beam transport severely limited the laser performance. To suppress the CSR effects, a new beam optics based on two double bend achromat (DBA) structures was introduced for the dogleg. After the replacement of the beam optics, high peak current bunches of more than 10 kA are now stably transported through the dogleg and the laser pulse output is increased by a factor of 2-3. In the multi-beam-line operation of SACLA, the electron beam parameters, such as the beam energy and peak current, can be adjusted independently for each beam line. Thus the laser output can be optimized and wide spectral tunability is ensured for all beam lines.

Interfering line in trace analysis by X-ray spectrometry: Radiative auger satellites

International Nuclear Information System (INIS)

Maeda, Kuniko; Kawai, Jun.

1994-01-01

Strong characteristic X-ray lines (e.g. Kα and Kβ) are accompanied by broad low-energy satellites caused by the radiative Auger effect (RAE). In order to prove how the RAE satellites interfere the analysis of minor elements, low-energy side spectra of Ca and Ti Kβ, and Ca-Fe Kα were measured. The obtained RAE intensities are summarized together with published experimental and theoretical data. The integrated intensities of satellites due to K → MM, K → LM and K → LL RAE relative to that of Kα are determined to be of the order of 0.01-0.1%. This warns that the neglecting of the RAE satellites will introduce a serious error in trace analysis. (author)

Influence of Laser Radiation Power Density on the Intensity of Spectral Lines for Main Components in a Clay Laser-Induced Plasma

Science.gov (United States)

Anufrik, S. S.; Kurian, N. N.; Znosko, K. F.; Belkov, M. V.

2018-05-01

We have studied the intensity of the spectral lines for the main components in clay: Al I 309.4 nm, Al II 358.7 nm, Mg II 279.6 nm, Ti II 323.6 nm vs. the position of the object relative to the focus of the optical system when the samples are exposed to single laser pulses from a YAG:Nd3+ laser. We have determined the permissible ranges for positioning the object relative to the focus of the optical system (positive and negative defocusing) for which there is practically no change in the reproducibility of the intensity for the spectral lines for red and white clay samples. We show that the position of the object relative to the focus of the optical system should be within the range ΔZ ±1.5 mm for optimal laser pulse energies for the analyte spectral lines. We have calculated the radiation flux density for different laser pulse energies and different distances from the focus to the object. We have shown experimentally that reducing the radiation flux density leads to a decrease in the intensity of the analyte spectral lines.

Recent results on celestial gamma radiation from SMM

Science.gov (United States)

Share, Gerald H.

1991-01-01

Observations made by the Gamma Ray Spectrometer on board the SMM are described. Recent results reported include observations and analyses of gamma-ray lines from Co-56 produced in supernovae, observations of the temporal variation of the 511 keV line observed during Galactic center transits, and measurements of the diffuse Galactic spectrum from 0.3 to 8.5 MeV. The work in progress includes measurements of the distribution of Galactic Al-26, observations to place limits on Galactic Ti-44 and Fe-60 and on Be-7 produced in novae, and searches for a characteristic gamma-ray emission from pair plasmas, a 2.223 MeV line emission, limits on deexcitation lines from interstellar C and O, and gamma-ray bursts.

The method of lines solution of discrete ordinates method for non-grey media

International Nuclear Information System (INIS)

Cayan, Fatma Nihan; Selcuk, Nevin

2007-01-01

A radiation code based on method of lines (MOL) solution of discrete ordinates method (DOM) for radiative heat transfer in non-grey absorbing-emitting media was developed by incorporation of a gas spectral radiative property model, namely wide band correlated-k (WBCK) model, which is compatible with MOL solution of DOM. Predictive accuracy of the code was evaluated by applying it to 1-D parallel plate and 2-D axisymmetric cylindrical enclosure problems containing absorbing-emitting medium and benchmarking its predictions against line-by-line solutions available in the literature. Comparisons reveal that MOL solution of DOM with WBCK model produces accurate results for radiative heat fluxes and source terms and can be used with confidence in conjunction with computational fluid dynamics codes based on the same approach

Effect of polarized radiative transfer on the Hanle magnetic field determination in prominences: Analysis of hydrogen H alpha line observations at Pic-du-Midi

Science.gov (United States)

Bommier, V.; Deglinnocenti, E. L.; Leroy, J. L.; Sahal-Brechot, S.

1985-01-01

The linear polarization of the Hydrogen H alpha line of prominences has been computed, taking into account the effect of a magnetic field (Hanle effect), of the radiative transfer in the prominence, and of the depolarization due to collisions with the surrounding electrons and protons. The corresponding formalisms are developed in a forthcoming series of papers. In this paper, the main features of the computation method are summarized. The results of computation have been used for interpretation in terms of magnetic field vector measurements from H alpha polarimetric observations in prominences performed at Pic-du-Midi coronagraph-polarimeter. Simultaneous observations in one optically thin line (He I D(3)) and one optically thick line (H alpha) give an opportunity for solving the ambiguity on the field vector determination.

Recent results concerning radiation-induced cancer in the Japanese atomic bomb survivors

International Nuclear Information System (INIS)

Radford, E.P.

1988-01-01

The most recent data of the prospective study among Hiroshima and Nagasaki atomic bomb survivors support the following conclusions: (a) the dose-response relationship is consistent with a straight line through the origin, including the lowest dose group (approx. 3 rad); (b) sensitivity to cancer induction varies considerably by irradiated tissues. (c) most cancers show a radiation effect still increasing 40 years after exposure; (d) a small leukemia excess among those irradiated is still present in Hiroshima; (e) the thyroid cancer excess is declining at present; (g) smoking adds to lung cancer incidence; (g) certain benign tumors show a radiation-related effect; (h) children under 10 years old at time of bombing are presently showing the highest relative cancer risk compared to other survivors at equal attained age. If this effect persists, age-specific cancer risk coefficients are necessary [fr

New theoretical results in synchrotron radiation

Energy Technology Data Exchange (ETDEWEB)

Bagrov, V.G. [Tomsk State University, Lenin Avenue 36, 634050 Tomsk (Russian Federation)]. E-mail: bagrov@phys.tsu.ru; Gitman, D.M. [Instituto de Fisica, Universidade de Sao Paulo, C.P. 66318, 05315-970 Sao Paulo, SP (Brazil); Tlyachev, V.B. [Tomsk Institute of High Current Electronics, Akademicheskiy Avenue 4, Tomsk (Russian Federation); Jarovoi, A.T. [Tomsk State University, Lenin Avenue 36, 634050 Tomsk (Russian Federation)

2005-11-15

One of the remarkable features of the relativistic electron synchrotron radiation is its concentration in small angle {delta}{approx}1/{gamma} (here {gamma}-relativistic factor: {gamma}=E/mc{sup 2}, E - energy, m - electron rest mass, c - light velocity) near rotation orbit plane [V.G. Bagrov, V.A. Bordovitsyn, V.G. Bulenok, V. Ya. Epp, Kinematical projection of pulsar synchrotron radiation profiles, in: Proceedings of IV ISTC Scientific Advisory Commitee Seminar on Basic Science in ISTC Aktivities, Akademgorodok, Novosibirsk, April 23-27, 2001, p. 293-300]. This theoretically predicted and experimentally confirmed feature is peculiar to total (spectrum summarized) radiating intensity. This angular distribution property has been supposed to be (at least qualitatively) conserved and for separate spectrum synchrotron radiation components. In the work of V.G. Bagrov, V.A. Bordovitsyn, V. Ch. Zhukovskii, Development of the theory of synchrotron radiation and related processes. Synchrotron source of JINR: the perspective of research, in: The Materials of the Second International Work Conference, Dubna, April 2-6, 2001, pp. 15-30 and in Angular dependence of synchrotron radiation intensity. http://lanl.arXiv.org/abs/physics/0209097, it is shown that the angular distribution of separate synchrotron radiation spectrum components demonstrates directly inverse tendency - the angular distribution deconcentration relatively the orbit plane takes place with electron energy growth. The present work is devoted to detailed investigation of this situation. For exact quantitative estimation of angular concentration degree of synchrotron radiation the definition of radiation effective angle and deviation angle is proposed. For different polarization components of radiation the dependence of introduced characteristics was investigated as a functions of electron energy and number of spectrum component.

Dedicated breast CT: radiation dose for circle-plus-line trajectory

International Nuclear Information System (INIS)

Vedantham, Srinivasan; Shi, Linxi; Karellas, Andrew; Noo, Frederic

2012-01-01

Purpose: Dedicated breast CT prototypes used in clinical investigations utilize single circular source trajectory and cone-beam geometry with flat-panel detectors that do not satisfy data-sufficiency conditions and could lead to cone beam artifacts. Hence, this work investigated the glandular dose characteristics of a circle-plus-line trajectory that fulfills data-sufficiency conditions for image reconstruction in dedicated breast CT. Methods: Monte Carlo-based computer simulations were performed using the GEANT4 toolkit and was validated with previously reported normalized glandular dose coefficients for one prototype breast CT system. Upon validation, Monte Carlo simulations were performed to determine the normalized glandular dose coefficients as a function of x-ray source position along the line scan. The source-to-axis of rotation distance and the source-to-detector distance were maintained constant at 65 and 100 cm, respectively, in all simulations. The ratio of the normalized glandular dose coefficient at each source position along the line scan to that for the circular scan, defined as relative normalized glandular dose coefficient (RD g N), was studied by varying the diameter of the breast at the chest wall, chest-wall to nipple distance, skin thickness, x-ray beam energy, and glandular fraction of the breast. Results: The RD g N metric when stated as a function of source position along the line scan, relative to the maximum length of line scan needed for data sufficiency, was found to be minimally dependent on breast diameter, chest-wall to nipple distance, skin thickness, glandular fraction, and x-ray photon energy. This observation facilitates easy estimation of the average glandular dose of the line scan. Polynomial fit equations for computing the RD g N and hence the average glandular dose are provided. Conclusions: For a breast CT system that acquires 300-500 projections over 2π for the circular scan, the addition of a line trajectory with equal

Radiation Calibration Measurements

International Nuclear Information System (INIS)

Omondi, C.

2017-01-01

KEBS Radiation Dosimetry mandate are: Custodian of Kenya Standards on Ionizing radiation, Ensure traceability to International System (SI ) and Calibration radiation equipment. RAF 8/040 on Radioisotope applications for troubleshooting and optimizing industrial process established Radiotracer Laboratory objective is to introduce and implement radiotracer technique for problem solving of industrial challenges. Gamma ray scanning technique applied is to Locate blockages, Locate liquid in vapor lines, Locate areas of lost refractory or lining in a pipe and Measure flowing densities. Equipment used for diagnostic and radiation protection must be calibrated to ensure Accuracy and Traceability

Radiation-induced transgenerational instability.

Science.gov (United States)

Dubrova, Yuri E

2003-10-13

To date, the analysis of mutation induction has provided an irrefutable evidence for an elevated germline mutation rate in the parents directly exposed to ionizing radiation and a number of chemical mutagens. However, the results of numerous publications suggest that radiation may also have an indirect effect on genome stability, which is transmitted through the germ line of irradiated parents to their offspring. This review describes the phenomenon of transgenerational instability and focuses on the data showing increased cancer incidence and elevated mutation rates in the germ line and somatic tissues of the offspring of irradiated parents. The possible mechanisms of transgenerational instability are also discussed.

The radiative heating response to climate change

Science.gov (United States)

Maycock, Amanda

2016-04-01

The structure and magnitude of radiative heating rates in the atmosphere can change markedly in response to climate forcings; diagnosing the causes of these changes can aid in understanding parts of the large-scale circulation response to climate change. This study separates the relative drivers of projected changes in longwave and shortwave radiative heating rates over the 21st century into contributions from radiatively active gases, such as carbon dioxide, ozone and water vapour, and from changes in atmospheric and surface temperatures. Results are shown using novel radiative diagnostics applied to timeslice experiments from the UM-UKCA chemistry-climate model; these online estimates are compared to offline radiative transfer calculations. Line-by-line calculations showing spectrally-resolved changes in heating rates due to different gases will also be presented.

Change of cell cycle arrest of tumor cell lines after 60Co γ-irradiation

International Nuclear Information System (INIS)

Tang Yi; Liu Wenli; Zhou Jianfeng; Gao Qinglei; Wu Jianhong

2003-01-01

Objective: To observe the cell cycle arrest changes in peripheral blood mononuclear cells (PBMNCs) of normal persons and several kinds of tumor cell lines after 60 Co γ-irradiation. Methods: PBMNCs of normal persons, HL-60, K562, SiHA and 113 tumor cell lines were irradiated with 60 Co γ-rays at the absorbed doses of 6, 10,15 Gy. Cell cycles changes were checked 6, 12, 24, 48 and 60 h after the irradiation. Results: A stasis state was observed in normal person PBMNCs, 95 percents of which were in G 1 phase, and they still remained stasis after the irradiation. Except the 113 cell line manifesting G 1 phase arrest, all other tumor cell lines showed G 2 /M phase arrest after irradiation. The radiation sensitivity of HL-60 was higher than that of SiHA cell line. Conclusion: Different cell lines have different cell cycle arrest reaction to radiation and their radiation sensitivity are also different

Investigation of the effect of radiation of DNA methylation patterns

International Nuclear Information System (INIS)

Kalinich, J.F.

1986-01-01

Four lines of cultured mammalian cells were used in this project: V79A03, a Chinese hamster lung fibroblast; HeLa S-3, an epithelial cell line from a human cervix carcinoma; CHO K-1, an epithelial cell line from a Chinese hamster ovary; and C-1300 N1E-115, a mouse neuroblastoma line. The 5-methylcytosine levels in DNA following exposure to cobalt-60 gamma radiation were measured. Induction of metallothionein in V79A03 cells and acetylcholinesterase in C-1300 N1E-115 cells after irradiation was determined and the effect of radiation on cytoplasmic and nuclear levels of DNA methyltransferase was studied and nuclear demethylase activity assayed. This study showed gamma radiation resulted in a decrease of 5-methylcytosine levels in the DNA of cultured mammalian cells. This radiation-induced hypomethylation resulted in the induction of acetylcholinesterase in mouse neuroblastoma cells and metallothionein in Chinese hamster lung fibroblasts and was caused by a decrease in DNA methyltransferase activity in the nucleus after irradiation and not by the presence of DNA demethylase

Results of performance tests on chemical and radiation measurement systems for use at a dig-face

International Nuclear Information System (INIS)

Gehrke, R.J.; Lawrence, R.S.; Pawelko, R.J.

1995-04-01

Chemical and radiation measurement systems are being developed for use at a dig-face to provide sensing capability during the excavation of previously buried waste. it is believed that on-line dig-face characterization will reduce environmental, health, and safety risks during the cleanup of buried waste sites as well as improve the efficiency of the cleanup process. This report describes progress in the development of three measurement systems: (a) a γ/neutron monitor that scans the dig-face for high levels of radiation prior to excavation, (b) a Ge spectrometer that identifies specific radionuclides located with the γ/neutron monitor, and (c) a prompt γ neutron activation analysis (PGNAA) system that measures the presence of chlorine and chlorinated compounds often associated with hazardous waste. The Ge spectrometer and PGNAA system also will provide off-line but on-site capability of radionuclide and elemental identification of excavated waste prior to handling, treatment, transportation, or disposal

Application of the spine-layer jet radiation model to outbursts in the broad-line radio galaxy 3C 120

Science.gov (United States)

Janiak, M.; Sikora, M.; Moderski, R.

2016-05-01

We present a detailed Fermi/LAT data analysis for the broad-line radio galaxy 3C 120. This source has recently entered into a state of increased γ-ray activity which manifested itself in two major flares detected by Fermi/LAT in 2014 September and 2015 April with no significant flux changes reported in other wavelengths. We analyse available data focusing our attention on aforementioned outbursts. We find very fast variability time-scale during flares (of the order of hours) together with a significant γ-ray flux increase. We show that the ˜6.8 yr averaged γ-ray emission of 3C 120 is likely a sum of the external radiation Compton and the synchrotron self-Compton radiative components. To address the problem of violent γ-ray flares and fast variability we model the jet radiation dividing the jet structure into two components: the wide and relatively slow outer layer and the fast, narrow spine. We show that with the addition of the fast spine occasionally bent towards the observer we are able to explain observed spectral energy distribution of 3C 120 during flares with the Compton upscattered broad-line region and dusty torus photons as main γ-rays emission mechanism.

HE0359-3959: An Extremely Radiating Quasar

Energy Technology Data Exchange (ETDEWEB)

Martínez-Aldama, M. L.; Del Olmo, A. [Instituto de Astrofísica de Andalucía, IAA-CSIC, Granada (Spain); Marziani, P. [INAF, Osservatorio Astronomico di Padova, Padua (Italy); Negrete, C. A. [CONACYT Research Fellow, Instituto de Astronomía, Universidad Nacional Autonoma de Mexico, Mexico City (Mexico); Dultzin, D. [Instituto de Astronomía, Universidad Nacional Autonoma de Mexico, Mexico City (Mexico); Martínez-Carballo, M. A., E-mail: maryloli@iaa.es [Instituto de Astrofísica de Andalucía, IAA-CSIC, Granada (Spain)

2017-11-28

We present a multiwavelength spectral study of the quasar HE0359-3959, which has been identified as an extreme radiating source at intermediate redshift (z = 1.5209). Along the spectral range, the different ionic species give information about the substructures in the broad line region. The presence of a powerful outflow with an extreme blueshifted velocity of ~–6,000 ± 500 km s{sup −1} is shown in the Civλ1549 emission line. A prominent blueshifted component is also associated with the 1900Å blend, resembling the one observed in Civλ1549. We detect a strong contribution of very the low–ionization lines, Feii and Near-Infrared Ca ii triplet. We find that the physical conditions for the low, intermediate, and high–ionization emission lines are different, which indicate that the emission lines are emitted in different zones of the broad line region. The asymmetries shown by the profiles reveal different forces over emitter zones. The high–ionization region is strongly dominated by radiation forces, which also affect the low and intermediate–ionization emitter region, commonly governed by virial motions. These results support the idea that highly radiating sources host a slim disk.

Beam transport radiation shielding for branch lines 2-ID-B and 2-ID-C

International Nuclear Information System (INIS)

Feng, Y.P.; Lai, B.; McNulty, I.; Dejus, R.J.; Randall, K.J.; Yun, W.

1995-01-01

The x-ray radiation shielding requirements beyond the first optics enclosure have been considered for the beam transport of the 2-ID-B and 2-ID-C branch lines of Sector 2 (SRI-CAT) of the APS. The first three optical components (mirrors) of the 2-ID-B branch are contained within the shielded first optics enclosure. Calculations indicate that scattering of the primary synchrotron beam by beamline components outside the enclosure, such as apertures and monochromators, or by gas particles in case of vacuum failure is within safe limits for this branch. A standard 2.5-inch-diameter stainless steel pipe with 1/16-inch-thick walls provides adequate shielding to reduce the radiation dose equivalent rate to human tissue to below the maximum permissible limit of 0.25 mrem/hr. The 2-ID-C branch requires, between the first optics enclosure where only two mirrors are used and the housing for the third mirror, additional lead shielding (0.75 mm) and a minimum approach distance of 2.6 cm. A direct beam stop consisting of at least 4.5 mm of lead is also required immediately downstream of the third mirror for 2-ID-C. Finally, to stop the direct beam from escaping the experimental station, a beam stop consisting of at least 4-mm or 2.5-mm steel is required for the 2-ID-B or 2-ID-C branches, respectively. This final requirement can be met by the vacuum chambers used to house the experiments for both branch lines

Modulation of interferon-gamma-induced HLA-DR expression on the human keratinocyte cell line SCC-13 by ultraviolet radiation

International Nuclear Information System (INIS)

Khan, I.U.; Boehm, K.D.; Elmets, C.A.

1993-01-01

Cell surface expression of major histocompatibility determinants on epidermal keratinocytes is a characteristic feature of a number of inflammatory dermatoses and in all likelihood is caused by diffusion of human leukocyte antigen (HLA)-DR-inducing cytokines from cells present in the dermal mononuclear cell infiltrate. Many of these same disorders respond to ultraviolet (UV) radiation phototherapy. Using the human SCC-13 keratinocyte cell line as a model, UV radiation was found to inhibit interferon-gamma-induced HLA-DR expression. Inhibition correlated closely with decreased steady-state levels of HLA-DR mRNA. These findings provide evidence that the therapeutic effect of UV radiation phototherapy may be mediated by its capacity to down-regulate cytokine-induced keratinocyte HLA-DR expression. (Author)

Electric-line-source illumination of a circular cylinder of lossless double-negative material: an investigation of near field, directivity, and radiation resistance

DEFF Research Database (Denmark)

Arslanagic, Samel; Breinbjerg, Olav

2006-01-01

the properties of the near field, inside as well as outside the cylinder, and the far-field. Third, the variations of these fields are examined, as well as the radiation resistance and radiation pattern, as functions of the geometrical and electromagnetic parameters of the configuration. It is demonstrated......This work investigates the properties of an antenna-like configuration with an electric line source radiating in the presence of a double-negative circular cylinder. First, the analytical eigenfunction-series solution is derived. Second, this solution is employed in numerical calculations to study...

Results of radiation therapy in periarthritis humeroscapularis

International Nuclear Information System (INIS)

Schultze, J.; Schlichting, G.; Galalae, R.; Kimmig, B.; Koltze, H.

2004-01-01

Background: radiation therapy is applied in painful degenerative shoulder diseases. Aim of this work was to evaluate the contribution of radiation therapy to symptomatic improvement in periarthritis humeroscapularis. Methods: ninety-four patients with periarthritis humeroscapularis were treated in two institutions. Mean age was 68 years, sex distribution were 32 men and 62 women. In 58 cases the right side was affected, left in 36 cases. At single doses of 0,75 Gy once a week a total dose of 6 Gy was applied The treatment effect was evaluated by the standardized von Pannewitz-score at the end of the treatment up to 6 months thereafter. Results: the treatment results of all the 94 patients were documentated at the end of therapy. Seventy-one patients were followed at least for further 4 months. Radiogenic side-effects were not noticed. The symptoms of 54 patients (57.4%) were improved or vanished, in 40 cases the symptoms were not significantly affected (42.6%). Four months after therapy 42 of 71 patients were improved (59.2%), 29 unchanged (40.8%). The treatment effect occured typically up to 2 months after therapy, there were no age-related differences. Also in recurrent radiation therapies the symptoms improved, in 80 percent after one preceding therapy, however only in 31.2 percent after multiple prior radiotherapies. (orig.)

Self-Consistent Dynamical Model of the Broad Line Region

Energy Technology Data Exchange (ETDEWEB)

Czerny, Bozena [Center for Theoretical Physics, Polish Academy of Sciences, Warsaw (Poland); Li, Yan-Rong [Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing (China); Sredzinska, Justyna; Hryniewicz, Krzysztof [Copernicus Astronomical Center, Polish Academy of Sciences, Warsaw (Poland); Panda, Swayam [Center for Theoretical Physics, Polish Academy of Sciences, Warsaw (Poland); Copernicus Astronomical Center, Polish Academy of Sciences, Warsaw (Poland); Wildy, Conor [Center for Theoretical Physics, Polish Academy of Sciences, Warsaw (Poland); Karas, Vladimir, E-mail: bcz@cft.edu.pl [Astronomical Institute, Czech Academy of Sciences, Prague (Czech Republic)

2017-06-22

We develop a self-consistent description of the Broad Line Region based on the concept of a failed wind powered by radiation pressure acting on a dusty accretion disk atmosphere in Keplerian motion. The material raised high above the disk is illuminated, dust evaporates, and the matter falls back toward the disk. This material is the source of emission lines. The model predicts the inner and outer radius of the region, the cloud dynamics under the dust radiation pressure and, subsequently, the gravitational field of the central black hole, which results in asymmetry between the rise and fall. Knowledge of the dynamics allows us to predict the shapes of the emission lines as functions of the basic parameters of an active nucleus: black hole mass, accretion rate, black hole spin (or accretion efficiency) and the viewing angle with respect to the symmetry axis. Here we show preliminary results based on analytical approximations to the cloud motion.

Self-Consistent Dynamical Model of the Broad Line Region

Directory of Open Access Journals (Sweden)

Bozena Czerny

2017-06-01

Full Text Available We develop a self-consistent description of the Broad Line Region based on the concept of a failed wind powered by radiation pressure acting on a dusty accretion disk atmosphere in Keplerian motion. The material raised high above the disk is illuminated, dust evaporates, and the matter falls back toward the disk. This material is the source of emission lines. The model predicts the inner and outer radius of the region, the cloud dynamics under the dust radiation pressure and, subsequently, the gravitational field of the central black hole, which results in asymmetry between the rise and fall. Knowledge of the dynamics allows us to predict the shapes of the emission lines as functions of the basic parameters of an active nucleus: black hole mass, accretion rate, black hole spin (or accretion efficiency and the viewing angle with respect to the symmetry axis. Here we show preliminary results based on analytical approximations to the cloud motion.

Strong nebular line ratios in the spectra of z ∼ 2-3 star forming galaxies: first results from KBSS-MOSFIRE

Energy Technology Data Exchange (ETDEWEB)

Steidel, Charles C.; Rudie, Gwen C.; Strom, Allison L.; Trainor, Ryan F.; Konidaris, Nicholas P.; Matthews, Keith [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, 1216 East California Boulevard., MS 249-17, Pasadena, CA 91125 (United States); Pettini, Max [Institute of Astronomy, Madingley Road, Cambridge CB3 0HA (United Kingdom); Reddy, Naveen A. [Department of Physics and Astronomy, University of California, Riverside, 900 University Avenue, Riverside, CA 92521 (United States); Shapley, Alice E.; Kulas, Kristin R.; Mace, Gregory; McLean, Ian S. [University of California, Los Angeles, Department of Physics and Astronomy, 430 Portola Plaza, Los Angeles, CA 90095 (United States); Erb, Dawn K. [Center for Gravitation, Cosmology, and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee, 1900 East Kenwood Boulevard, Milwaukee, WI 53211 (United States); Turner, Monica L. [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands)

2014-11-10

We present initial results of a deep near-IR spectroscopic survey covering the 15 fields of the Keck Baryonic Structure Survey using the recently commissioned MOSFIRE spectrometer on the Keck 1 telescope. We focus on a sample of 251 galaxies with redshifts 2.0 < z < 2.6, star formation rates (SFRs) 2 ≲ SFR ≲ 200 M {sub ☉} yr{sup –1}, and stellar masses 8.6 < log (M {sub *}/M {sub ☉}) < 11.4, with high-quality spectra in both H- and K-band atmospheric windows. We show unambiguously that the locus of z ∼ 2.3 galaxies in the 'BPT' nebular diagnostic diagram exhibits an almost entirely disjointed, yet similarly tight, relationship between the line ratios [N II] λ6585/Hα and [O III]/Hβ as compared to local galaxies. Using photoionization models, we argue that the offset of the z ∼ 2.3 BPT locus relative to that at z ∼ 0 is caused by a combination of harder stellar ionizing radiation field, higher ionization parameter, and higher N/O at a given O/H compared to most local galaxies, and that the position of a galaxy along the z ∼ 2.3 star-forming BPT locus is surprisingly insensitive to gas-phase oxygen abundance. The observed nebular emission line ratios are most easily reproduced by models in which the net stellar ionizing radiation field resembles a blackbody with effective temperature T {sub eff} = 50, 000-60, 000 K, the gas-phase oxygen abundances lie in the range 0.2 < Z/Z {sub ☉} < 1.0, and the ratio of gas-phase N/O is close to the solar value. We critically assess the applicability at high redshift of commonly used strong line indices for estimating gas-phase metallicity, and consider the implications of the small intrinsic scatter of the empirical relationship between excitation-sensitive line indices and M {sub *} (i.e., the 'mass-metallicity' relation) at z ≅ 2.3.

Strong nebular line ratios in the spectra of z ∼ 2-3 star forming galaxies: first results from KBSS-MOSFIRE

International Nuclear Information System (INIS)

Steidel, Charles C.; Rudie, Gwen C.; Strom, Allison L.; Trainor, Ryan F.; Konidaris, Nicholas P.; Matthews, Keith; Pettini, Max; Reddy, Naveen A.; Shapley, Alice E.; Kulas, Kristin R.; Mace, Gregory; McLean, Ian S.; Erb, Dawn K.; Turner, Monica L.

2014-01-01

We present initial results of a deep near-IR spectroscopic survey covering the 15 fields of the Keck Baryonic Structure Survey using the recently commissioned MOSFIRE spectrometer on the Keck 1 telescope. We focus on a sample of 251 galaxies with redshifts 2.0 < z < 2.6, star formation rates (SFRs) 2 ≲ SFR ≲ 200 M ☉ yr –1 , and stellar masses 8.6 < log (M * /M ☉ ) < 11.4, with high-quality spectra in both H- and K-band atmospheric windows. We show unambiguously that the locus of z ∼ 2.3 galaxies in the 'BPT' nebular diagnostic diagram exhibits an almost entirely disjointed, yet similarly tight, relationship between the line ratios [N II] λ6585/Hα and [O III]/Hβ as compared to local galaxies. Using photoionization models, we argue that the offset of the z ∼ 2.3 BPT locus relative to that at z ∼ 0 is caused by a combination of harder stellar ionizing radiation field, higher ionization parameter, and higher N/O at a given O/H compared to most local galaxies, and that the position of a galaxy along the z ∼ 2.3 star-forming BPT locus is surprisingly insensitive to gas-phase oxygen abundance. The observed nebular emission line ratios are most easily reproduced by models in which the net stellar ionizing radiation field resembles a blackbody with effective temperature T eff = 50, 000-60, 000 K, the gas-phase oxygen abundances lie in the range 0.2 < Z/Z ☉ < 1.0, and the ratio of gas-phase N/O is close to the solar value. We critically assess the applicability at high redshift of commonly used strong line indices for estimating gas-phase metallicity, and consider the implications of the small intrinsic scatter of the empirical relationship between excitation-sensitive line indices and M * (i.e., the 'mass-metallicity' relation) at z ≅ 2.3.

Protective effect of infrared-A radiation against damage induced by UVB radiation in the melan-a cell line.

Science.gov (United States)

Portantiolo Lettnin, Aline; Teixeira Santos Figueiredo Salgado, Mariana; Gonsalez Cruz, Camila; Manoel Rodrigues da Silva-Júnior, Flávio; Cunha Gonzalez, Vinícius; de Souza Votto, Ana Paula; Santos Trindade, Gilma; de Moraes Vaz Batista Filgueira, Daza

2016-10-01

The present work evaluated the infrared-A (IR-A) protective effect using a light-emitting diode (LED) lamp against the cytotoxic effects of ultraviolet B radiation (UVB). Effects on cell viability (Trypan blue assay), DNA damage (comet assay), lipid peroxidation (FOX method), reactive oxygen species production and antioxidant capacity were analyzed in melan-a, a non-tumoral murine melanocytic cell line. To define the doses used in the interaction experiments between IR-A+UVB, dose/response curves were made after exposure to IR-A or UVB. The IR-A dose chosen was 0.8J/cm(2) because this dose caused no significant inhibition of proliferation effects and viability decreased. For UVB exposure, a dose of 0.015J/cm(2), which showed a decrease in viable cell number by approximately 50% in relation to control until 72h, was selected. For IR-A+UVB, cell proliferation recovery was showed, decreasing DNA damage and lipid peroxide content when compared to UVB alone. Besides, the results obtained for ROS and antioxidant capacity showed that the protection observed was probably not related to decreased oxidative stress. In conclusion, non-thermal IR-A was capable of protecting the melan-a cells from UVB induced damage. Copyright © 2016 Elsevier B.V. All rights reserved.

Construction of a line for radiation cross-linking of cable insulators at the Kablo Vrchlabi plant

International Nuclear Information System (INIS)

Kourim, P.; Zidek, L.; Kopecky, B.

1983-01-01

In order to introduce radiation curing into the technology of manufacturing conductors with silicone insulation the suitability was tested of the individual brands of silicone rubber used for cables. The criterion was the range of doses guaranteeing the required mechanical and rheological properties of the rubber. The ELV 1 accelerator was used for irradiation. A description is given of the design of the technological equipment of the line which was put into experimental operation. (J.P.)

Tumourigenicity and radiation resistance of mesenchymal stem cells.

Science.gov (United States)

D'Andrea, Filippo P; Horsman, Michael R; Kassem, Moustapha; Overgaard, Jens; Safwat, Akmal

2012-05-01

Cancer stem cells are believed to be more radiation resistant than differentiated tumour cells of the same origin. It is not known, however, whether normal nontransformed adult stem cells share the same radioresistance as their cancerous counterpart. Nontumourigenic (TERT4) and tumourigenic (TRET20) cell lines, from an immortalised mesenchymal stem cell line, were grown in culture prior to irradiation and gene expression analysis. Radiation resistance was measured using a clonogenic assay. Differences in gene expression between the two cell lines, both under nontreated and irradiated conditions, were assessed with microarrays (Affymetrix Human Exon 1.0 ST array). The cellular functions affected by the altered gene expressions were assessed through gene pathway mapping (Ingenuity Pathway Analysis). Based on the clonogenic assay the nontumourigenic cell line was found to be more sensitive to radiation than the tumourigenic cell line. Using the exon chips, 297 genes were found altered between untreated samples of the cell lines whereas only 16 genes responded to radiation treatment. Among the genes with altered expression between the untreated samples were PLAU, PLAUR, TIMP3, MMP1 and LOX. The pathway analysis based on the alteration between the untreated samples indicated cancer and connective tissue disorders. This study has shown possible common genetic events linking tumourigenicity and radiation response. The PLAU and PLAUR genes are involved in apoptosis evasion while the genes TIMP3, MMP1 and LOX are involved in regulation of the surrounding matrix. The first group may contribute to the difference in radiation resistance observed and the latter could be a major contributor to the tumourigenic capabilities by degrading the intercellular matrix. These results also indicate that cancer stem cells are more radiation resistant than stem cells of the same origin.

Radiation effects on cultured human lymphoid cells

International Nuclear Information System (INIS)

Johansson, L.; Nilsson, K.; Carlsson, J.; Larsson, B.; Jakobsson, P.

1981-01-01

The cloning efficiency of human normal and malignant lymphoid cells is usually low. Radiation effects in vitro on such cells can therefore not be analysed with conventional cloning. However, this problem can be circumscribed by using the growth extrapolation method. A panel of human leukemia-lymphoma cell-lines representing Epstein-Barr virus carrying lymphoblastoid cells of presumed non-neoplastic derivation and neoplastic T- and B-lymphocytes was used to test the efficiency of this method. The sensitivity to radiation could be determined for all these cell types. The growth extrapolation method gave generally the same result as conventional cloning demonstrated by comparison with one exceptional cell-line with capacity for cloning in agar. The sensitivity varied largely between the different cell types. A common feature was that none of the cell lines had a good capacity to accumulate sublethal radiation injury. (Auth.)

A conjugate gradient method for solving the non-LTE line radiation transfer problem

Science.gov (United States)

Paletou, F.; Anterrieu, E.

2009-12-01

This study concerns the fast and accurate solution of the line radiation transfer problem, under non-LTE conditions. We propose and evaluate an alternative iterative scheme to the classical ALI-Jacobi method, and to the more recently proposed Gauss-Seidel and successive over-relaxation (GS/SOR) schemes. Our study is indeed based on applying a preconditioned bi-conjugate gradient method (BiCG-P). Standard tests, in 1D plane parallel geometry and in the frame of the two-level atom model with monochromatic scattering are discussed. Rates of convergence between the previously mentioned iterative schemes are compared, as are their respective timing properties. The smoothing capability of the BiCG-P method is also demonstrated.

NASA Space Radiation Risk Project: Overview and Recent Results

Science.gov (United States)

Blattnig, Steve R.; Chappell, Lori J.; George, Kerry A.; Hada, Megumi; Hu, Shaowen; Kidane, Yared H.; Kim, Myung-Hee Y.; Kovyrshina, Tatiana; Norman, Ryan B.; Nounu, Hatem N.;

Radiation Response of Cancer Stem-Like Cells From Established Human Cell Lines After Sorting for Surface Markers

International Nuclear Information System (INIS)

Al-Assar, Osama; Muschel, Ruth J.; Mantoni, Tine S.; McKenna, W. Gillies; Brunner, Thomas B.

2009-01-01

Purpose: A subpopulation of cancer stem-like cells (CSLC) is hypothesized to exist in different cancer cell lines and to mediate radioresistance in solid tumors. Methods and Materials: Cells were stained for CSLC markers and sorted (fluorescence-activated cell sorter/magnetic beads) to compare foci and radiosensitivity of phosphorylated histone H2AX at Ser 139 (γ-H2AX) in sorted vs. unsorted populations in eight cell lines from different organs. CSLC properties were examined using anchorage-independent growth and levels of activated Notch1. Validation consisted of testing tumorigenicity and postirradiation enrichment of CSLC in xenograft tumors. Results: The quantity of CSLC was generally in good agreement with primary tumors. CSLC from MDA-MB-231 (breast) and Panc-1 and PSN-1 (both pancreatic) cells had fewer residual γ-H2AX foci than unsorted cells, pointing to radioresistance of CSLC. However, only MDA-MB-231 CSLC were more radioresistant than unsorted cells. Furthermore, MDA-MB-231 CSLC showed enhanced anchorage-independent growth and overexpression of activated Notch1 protein. The expression of cancer stem cell surface markers in the MDA-MB-231 xenograft model was increased after exposure to fractionated radiation. In contrast to PSN-1 cells, a growth advantage for MDA-MB-231 CSLC xenograft tumors was found compared to tumors arising from unsorted cells. Conclusions: CSLC subpopulations showed no general radioresistant phenotype, despite the quantities of CSLC subpopulations shown to correspond relatively well in other reports. Likewise, CSLC characteristics were found in some but not all of the tested cell lines. The reported problems in testing for CSLC in cell lines may be overcome by additional techniques, beyond sorting for markers.

Diagnostics of red-shifted H-alpha line emission from a C-class flare with full non-LTE radiative and hydrodynamic approach

Science.gov (United States)

Druett, M. K.; Zharkova, V. V.; Scullion, E.; Zharkov, S.; Matthews, S. A.

2016-12-01

We analyse H-alpha line profiles with strong redshifts during the C1.8 flare on 1st July 2012 obtained from the Swedish Solar Telescope (SST) closely resembling the previous observations (Wuelser and Marti, 1989). The flare has a magnetic field configuration with two levels of loop structures. The kernels with red shifts are observed in one of the H-alpha ribbons in the south-west location formed after the main impulse recorded in the north-east. The locations of H-alpha kernels with red shifts reveal close temporal and spatial correlation with weaker HXR signatures and coincide with the locations of coronal jets observed with AIA/SDO. For interpretation we apply a revised 1D hydrodynamic and non-LTE (NLTE) radiative model for 5 level plus continuum model hydrogen atom (Druett & Zharkova, 2016) considering radiative, thermal and non-thermal excitation and ionisation by beam electrons with the updated beam densities (Zharkova & Dobranskis, 2016) and analytical excitation/ionisation rates (Zharkova& Kobylinskijj, 1993). We find the simultaneous solutions of steady state and radiative transfer equations in all optically-thick lines and continua. The electron and ion temperatures, ambient density and macrovelocity of the ambient plasma are derived from a 1D hydrodynamic model with initial condition of the pre-flaring photosphere for the two fluid ambient plasma heated by beam electrons (Zharkova & Zharkov, 2007). We simulate distributions over precipitation depth of ionisation and departure coefficients for all the hydrogen atom transitions including the deviation of ionisation from Saha equation affected by non-thermal electron beams. We show that in the very first seconds after the beam onset Balmer line profiles are sensitive to the effect of beam electrons. The combination of the additional ionisation caused by beam electrons leading to a very strong Stark effect in Balmer lines with the hydrodynamic heating and formation of a low temperature shock in the

Accreditation and radiation protection - the cost or smaller doses and reliable results

International Nuclear Information System (INIS)

Omahen, G.; Zdesar, U.

2011-01-01

Laboratories involved in the protection against radiation and therefore in the measurement of radioactivity, dose rate and contamination have always been tied to the quality of their measurements, particularly those that have performed measurements for nuclear power plants. However in the laboratories more than quality it was more important, that people are professional, that they are engaged in scientific work and know how to interpret the results. Very often these are things that do not go along with reviewing the measuring instruments and quality records. However customer requires measurement results that can be trusted. This is the purpose of the standard SIST EN ISO / IEC 17025 in which the requirements for testing and calibration laboratories are standardised. The standard in force since 1999. In some countries, requests for accreditation of testing laboratories according to SIST EN ISO / IEC 17025 is even in regulation. This request is for example in the Croatian and Slovenian regulations for laboratories involved in measuring the radioactivity, dose rate, contamination, or by checking the X-ray apparatus. Several laboratories have been accreditation for several years. From that experience we can conclude that customer gets reliable results from the accredited laboratories at relatively low cost. On the other side laboratory which his accredited has introduced a line of work and his laboratory, there are rules for equipment, personnel, training and all that eventually enhanced measurement expertise. With accreditation, it is much easier to compensate for the loss of workers due to pension or leaving the laboratory because every moment must always be in the laboratory at least two who know how to work on the method. Accreditation is not improving radiation protection or reducing Becquerel in the air. But at least we know how accurate mSv or Bq are and how small mSv and Bq can be measured. (author) [sr

Activities of the Institute of Radiation Protection and Dosimetry on radiation overexposure analysis - results from 1994 to 1997

International Nuclear Information System (INIS)

Silva, Francisco C.A. da; Ramalho, Adriana

1999-01-01

Since 1985 the Institute of Radiation Protection and Dosimetry has operated a service carried out by a multi-disciplinary Group called Radiation Overexposure analysis Group - GADE. It is composed of specialists in radiation protection and dosimetry and has the main objective of taking coordinated actions on radiation overexposure cases. This paper shows mainly the results got from 1984 to 1997 with the methodology used. It was observed that the cases are falling down due to radiation protection activities in the installation. (author)

Radiation-induced germ-line mutations detected by a direct comparison of parents and children DNA sequences containing SNPs

International Nuclear Information System (INIS)

Morimyo, M.; Hongo, E.; Higashi, T.; Wu, J.; Matsumoto, I.; Okamoto, M.; Kawano, A.; Tsuji, S.

2003-01-01

Full text: Germ-line mutation is detected in mice but not in humans. To estimate genetic risk of humans, a new approach to extrapolate from animal data to humans or to directly detect radiation-induced mutations in man is expected. We have developed a new method to detect germ-line mutations by directly comparing DNA sequences of parents and children. The nucleotide sequences among mouse strains are almost identical except SNP markers that are detected at 1/1000 frequency. When gamma-irradiated male mice are mated with female mice, heterogeneous nucleotide sequences induced in children DNA are a candidate of mutation, whose assignment can be done by SNP analysis. This system can easily detect all types of mutations such as transition, transversion, frameshift and deletion induced by radiation and can be applied to humans having genetically heterogeneous nucleotide sequences and many SNP markers. C3H male mice of 8 weeks of gestation were irradiated with gamma rays of 3 and 1 Gy and after 3 weeks, they were mated with the same aged C57BL female mice. After 3 weeks breeding, DNA was extracted from parents and children mice. The nucleotide sequences of 150 STS markers containing 300-900 bp and SNPs of parents and children DNA were determined by a direct sequencing; amplification of STS markers by Taq DNA polymerase, purification of PCR products, and DNA sequencing with a dye-terminator method. At each radiation dose, a total amount of 5 Mb DNA sequences were examined to detect radiation-induced mutations. We could find 6 deletions in 3 Gy irradiated mice but not in 1 Gy and control mice. The mutation frequency was about 4.0 x 10 -7 /bp/ Gy or 1.6 x 10 -4 /locus/Gy, and suggested the non-linear increase of mutation rate with dose

Fluid Line Evacuation and Freezing Experiments for Digital Radiator Concept

Science.gov (United States)

Berisford, Daniel F.; Birur, Gajanana C.; Miller, Jennifer R.; Sunada, Eric T.; Ganapathi, Gani B.; Stephan, Ryan; Johnson, Mark

2011-01-01

The digital radiator technology is one of three variable heat rejection technologies being investigated for future human-rated NASA missions. The digital radiator concept is based on a mechanically pumped fluid loop with parallel tubes carrying coolant to reject heat from the radiator surface. A series of valves actuate to start and stop fluid flow to di erent combinations of tubes, in order to vary the heat rejection capability of the radiator by a factor of 10 or more. When the flow in a particular leg is stopped, the fluid temperature drops and the fluid can freeze, causing damage or preventing flow from restarting. For this reason, the liquid in a stopped leg must be partially or fully evacuated upon shutdown. One of the challenges facing fluid evacuation from closed tubes arises from the vapor generated during pumping to low pressure, which can cause pump cavitation and incomplete evacuation. Here we present a series of laboratory experiments demonstrating fluid evacuation techniques to overcome these challenges by applying heat and pumping to partial vacuum. Also presented are results from qualitative testing of the freezing characteristics of several different candidate fluids, which demonstrate significant di erences in freezing properties, and give insight to the evacuation process.

Cultivation studies of Taiwanese native Miscanthus floridulus lines

International Nuclear Information System (INIS)

Huang, C.L.; Liao, W.C.; Lai, Y.C.

2011-01-01

Four Taiwanese native Miscanthus floridulus lines, collected at altitudes of 260, 500, 1000, and 1500 m were cultivated in 2009 and 2010. The plant height and tiller numbers of four M. floridulus lines increased gradually along with the growing time. These M. floridulus lines had the tallest plant height and most tiller number after these species were planted 210 days. Line 3, which was collected at the altitude of 1000 m, had the ability to grow at low temperature. Line 3 M. floridulus had the highest plant height, tiller number, fresh and dry yields than other three lines. Fresh and dry yields of Line 3 were positively correlated to the plant height, tiller number, and leaf width, but showed no correlation with the leaf length. The correlation between agronomic traits and climatic data was also studied. Results can be used as a model for developing a non-food crop-based energy production system in the future. -- Highlights: → Miscanthus floridulus collected at 1000 m altitude had the highest plant height, tiller number, fresh and dry yields. → Fresh and dry yields of were positively correlated to the plant height, tiller number, and leaf width. → Fresh and dry yields showed no correlation with the leaf length. → The accumulative rainfall, temperature, radiation, and exposure time to radiation were positively correlated to the plant height, leaf length and leaf width.

Man-made radionuclides in the environment and resulting radiation exposures

International Nuclear Information System (INIS)

Michel, R.

2009-01-01

This contribution gives a survey about the sources of man-made environmental radioactivity and quantifies some of the resulting radiation exposures. The relevance of the different radionuclides with respect to the radiation exposures is discussed. Finally, the question of the effects of small doses is addressed. (orig.)

High flux and high resolution VUV beam line for synchrotron radiation

International Nuclear Information System (INIS)

Wilcke, H.; Boehmer, W.; Schwentner, N.

1982-04-01

A beam line has been optimized for high flux and high resolution in the wavelength range from 30 nm to 300 nm. Sample chambers for luminescence spectroscopy on gaseous, liquid and solid samples and for photoelectron spectroscopy have been integrated. The synchrotron radiation from the storage ring DORIS (at DESY, Hamburg) emitted into 50 mrad in horizontal and into 2.2 mrad in vertical direction is focused by a cylindrical and a plane elliptical mirror into the entrance slit of a 2m normal incidence monochromator. The light flux from the exit slit is focused by a rotational elliptic mirror onto the sample yielding a size of the light spot of 4 x 0.15 mm 2 . The light flux at the sample reaches 7 x 10 12 photons nm -1 s -1 at 8 eV photon energy for a current of 100 mA in DORIS. A resolution of 0.007 nm has been obtained. (orig.)

Radiation damage of light guide fibers in gamma radiation field - on-line monitoring of absorption centers formation

International Nuclear Information System (INIS)

Blaha, J.; Simane, C.; Finger, M.; Slunecka, M.; Finger, M. Jr.; Sluneckova, V.; Janata, A.; Vognar, M.; Sulc, M.

2004-01-01

The kinetics of radiation-induced changes of absorption coefficient was studied by online transmission spectra measurement for two different Kuraray light guide fibers. The samples were irradiated by bremsstrahlung gamma radiation, dose rates were from 2 Gy/s to 25 Gy/s. The kinetic coefficients both for absorption centers formation and for recovery processes were calculated. Good agreement of experimental data and simple one-short-lived absorption center model were received for radiation-hard light guide Kuraray (KFC). The more complicated process was observed on Kuraray (PSM) clear fiber. It was caused by the reaction of the oxygen dissolved in fiber and created radicals. The results are very useful for prediction of an optical fibers response in conditions of new nuclear and particle physics experiments. (author)

A study on radiation shielding and safety analysis for a synchrotron radiation beamline

International Nuclear Information System (INIS)

Asano, Yoshihiro

2001-03-01

Methods of shielding design and safety analysis are presented for a beam-line of synchrotron radiation. This paper consists of the shielding and safety study of synchrotron radiation with extremely intense and low energy photon below several hundreds keV, and the study for the behavior of remarkable high-energy photons up to 8 GeV, which can creep into beam-lines. A new shielding design code, STAC8 was developed to estimate the leakage dose outside the beam line hutch (an enclosure of the beam, optical elements or experimental instruments) easily and quickly with satisfactory accuracy. The code can calculate consistently from sources of synchrotron radiation to dose equivalent outside hutches with considering the build up effect and polarization effect. Validity of the code was verified by comparing its calculations with those of Monte Carlo simulations and measurement results of the doses inside the hutch of the BL14C of Photon Factory in the High Energy Accelerator Research Organization (KEK), showing good agreements. The shielding design calculations using STAC8 were carried out to apply to the practical beam-lines with the considering polarization effect and clarified the characteristics of the typical beam-line of the third generation synchrotron radiation facility, SPring-8. In addition, the shielding calculations were compared with the measurement outside the shield wall of the bending magnet beam-line of SPring-8, and showed fairly good agreement. The new shielding problems, which have usually been neglected in shielding designs for existing synchrotron radiation facilities, are clarified through the analysis of the beam-line shielding of SPring-8. The synchrotron radiation from the SPring-8 has such extremely high-intensity involving high energy photons that the scattered synchrotron radiation from the concrete floor of the hutch, the ground shine, causes a seriously high dose. The method of effective shielding is presented. For the estimation of the gas

A study on radiation shielding and safety analysis for a synchrotron radiation beamline

Energy Technology Data Exchange (ETDEWEB)

Asano, Yoshihiro [Japan Atomic Energy Research Inst., Kansai Research Establishment, Synchrotron Radiation Research Center, Mikazuhi, Hyogo (Japan)

2001-03-01

Methods of shielding design and safety analysis are presented for a beam-line of synchrotron radiation. This paper consists of the shielding and safety study of synchrotron radiation with extremely intense and low energy photon below several hundreds keV, and the study for the behavior of remarkable high-energy photons up to 8 GeV, which can creep into beam-lines. A new shielding design code, STAC8 was developed to estimate the leakage dose outside the beam line hutch (an enclosure of the beam, optical elements or experimental instruments) easily and quickly with satisfactory accuracy. The code can calculate consistently from sources of synchrotron radiation to dose equivalent outside hutches with considering the build up effect and polarization effect. Validity of the code was verified by comparing its calculations with those of Monte Carlo simulations and measurement results of the doses inside the hutch of the BL14C of Photon Factory in the High Energy Accelerator Research Organization (KEK), showing good agreements. The shielding design calculations using STAC8 were carried out to apply to the practical beam-lines with the considering polarization effect and clarified the characteristics of the typical beam-line of the third generation synchrotron radiation facility, SPring-8. In addition, the shielding calculations were compared with the measurement outside the shield wall of the bending magnet beam-line of SPring-8, and showed fairly good agreement. The new shielding problems, which have usually been neglected in shielding designs for existing synchrotron radiation facilities, are clarified through the analysis of the beam-line shielding of SPring-8. The synchrotron radiation from the SPring-8 has such extremely high-intensity involving high energy photons that the scattered synchrotron radiation from the concrete floor of the hutch, the ground shine, causes a seriously high dose. The method of effective shielding is presented. For the estimation of the gas

SU-F-T-678: Clotrimazole Sensitizes MCF-7 Breast Cancer Cell Line to Radiation

Energy Technology Data Exchange (ETDEWEB)

Garcia, L; Tambasco, M [San Diego State University, San Diego, CA (United States)

2016-06-15

Purpose: To study the effects of Clotrimazole (CLT) on radiosensitivity of MCF-7 Cells in correlation to detachment of Hexokinase II from the Voltage Dependent Anion Channel on the outer membrane of the mitochondria. Apoptotic fractions were also analyzed in relation to the detachment of Hexokinase. Methods: This study focused on the mammary adenocarcinoma cell line, MCF-7. Colony forming assays were used to analyze radiosensitization by CLT. Flow cytometry methods were used to analyze apoptotic vs necrotic fractions after treatment with CLT. Spectrophotometery was used to analyze the mitochondrial bound and soluble fraction of Hexokinase by means of relative enzymatic activity. Results: Our preliminary data have shown that CLT sensitizes MCF-7 cells to radiation in a dose and incubation time dependent manner up. We have also demonstrated that there are two radiosensitizing periods in MCF-7 cells with the first corresponding to the cycle arrest after 24 hours observed in other cell lines. The second radiosensitizing period occurs with incubation in CLT after irradiation which reaches maximum effect around 24 hours of incubation time. Preliminary data from our Hexokinase detachment assay show a factor of two increase in the ratio of unbound to bound Hexokinase when comparing incubation for 24 hours in media containing 0 and 20 µM CLT. Conclusion: This study and others indicate CLT as a possible radiosensitizing agent in cancer therapies. While CLT itself shows toxicity to the liver in high doses, this study further demonstrates that disruption of the Warburg Effect and unbinding of mitochondrial bound Hexokinase as a possible pathway for cancer treatment.

SU-F-T-678: Clotrimazole Sensitizes MCF-7 Breast Cancer Cell Line to Radiation

International Nuclear Information System (INIS)

Garcia, L; Tambasco, M

2016-01-01

Purpose: To study the effects of Clotrimazole (CLT) on radiosensitivity of MCF-7 Cells in correlation to detachment of Hexokinase II from the Voltage Dependent Anion Channel on the outer membrane of the mitochondria. Apoptotic fractions were also analyzed in relation to the detachment of Hexokinase. Methods: This study focused on the mammary adenocarcinoma cell line, MCF-7. Colony forming assays were used to analyze radiosensitization by CLT. Flow cytometry methods were used to analyze apoptotic vs necrotic fractions after treatment with CLT. Spectrophotometery was used to analyze the mitochondrial bound and soluble fraction of Hexokinase by means of relative enzymatic activity. Results: Our preliminary data have shown that CLT sensitizes MCF-7 cells to radiation in a dose and incubation time dependent manner up. We have also demonstrated that there are two radiosensitizing periods in MCF-7 cells with the first corresponding to the cycle arrest after 24 hours observed in other cell lines. The second radiosensitizing period occurs with incubation in CLT after irradiation which reaches maximum effect around 24 hours of incubation time. Preliminary data from our Hexokinase detachment assay show a factor of two increase in the ratio of unbound to bound Hexokinase when comparing incubation for 24 hours in media containing 0 and 20 µM CLT. Conclusion: This study and others indicate CLT as a possible radiosensitizing agent in cancer therapies. While CLT itself shows toxicity to the liver in high doses, this study further demonstrates that disruption of the Warburg Effect and unbinding of mitochondrial bound Hexokinase as a possible pathway for cancer treatment.

Initial analyses of surface spectral radiance between observations and Line-By-Line calculations

Energy Technology Data Exchange (ETDEWEB)

Brown, P.D.; Clough, S.A. [Atmospheric and Environmental Research, Inc., Cambridge, MA (United States); Miller, N.E.; Shippert, T.R.; Turner, D.D. [Pacific Northwest Lab., Richland, WA (United States)] [and others

1996-04-01

The evaluation an improvement of radiative transfer calculations are essential to attain improved performance of general circulation models (GCMs) for climate change applications. A Quality Measurement Experiment (QME) is being conducted to analyze the spectral residuals between the downwelling longwave radiance measured by the University of Wisconsin Atmospheric Emitted Radiance Interferometer (AERI) and spectral radiance calculated by the Line-By-Line Radiative Transfer Model (LBLRTM). The three critical components of this study are (1) the assessment of the quality of the high resolution AERI measurements, (2) the assessment of the ability to define the atmospheric state in the radiating column, and (3) the evaluation of the capability of LBLRTM. Validations have been performed on spectral radiance data, obtained from April 1994 through July 1994, through the analysis of the spectral interval and physical process. The results are archived as a function of time, enabling the retrieval of specific data and facilitating investigations and diurnal effects, seasonal effects, and longer-term trends. While the initial focus is restricted to clear-sky analyses, efforts are under way to include the effects of clouds and aerosols. Plans are well formulated for the extension of the current approach to the shortwave. An overview of the concept of the QME is described by Miller et al. (1994), and a detailed description of this study is provided by Clough et al. (1994).

Variety of Polarized Line Profiles in Interacting Supernovae

Science.gov (United States)

Hoffman, Jennifer L.; Huk, L. N.; Peters, C. L.

2013-01-01

The dense circumstellar material that creates strong emission lines in the spectra of interacting supernovae also gives rise to complex line polarization behavior. Viewed in polarized light, the emission line profiles of these supernovae encode information about the geometrical and optical characteristics of their surrounding circumstellar material (CSM) that is inaccessible by other observational techniques. To facilitate quantitative interpretation of these spectropolarimetric signatures, we have created a large grid of model polarized line profiles using a three-dimensional radiative transfer code that simulates polarization via electron and resonant/fluorescent line scattering. The simulated polarized lines take on an array of profile shapes that vary with viewing angle and CSM properties. We present the major results from the grid and investigate the dependence of polarized line profiles on CSM characteristics including temperature, optical depth, and geometry. These results will allow more straightforward interpretation of polarized line profiles in interacting supernovae than has previously been possible. This research is supported by the National Science Foundation through the AAG program and the XSEDE collaboration, and uses the resources of the Texas Advanced Computing Center.

Recent developments in the line-by-line modeling of outgoing longwave radiation

International Nuclear Information System (INIS)

Buehler, S.A.; Engeln, A. von; Brocard, E.; John, V.O.; Kuhn, T.; Eriksson, P.

2006-01-01

High frequency resolution radiative transfer model calculations with the Atmospheric Radiative Transfer Simulator (ARTS) were used to simulate the clear-sky outgoing longwave radiative flux (OLR) at the top of the atmosphere. Compared to earlier calculations by Clough and coworkers the model used a spherical atmosphere instead of a plane parallel atmosphere, updated spectroscopic parameters from HITRAN, and updated continuum parameterizations from Mlawer and coworkers. These modifications lead to a reduction in simulated OLR by approximately 4.1%, the largest part, approximately 2.5%, being due to the absence of the plane parallel approximation. As a simple application of the new model, the sensitivity of OLR to changes in humidity, carbon dioxide concentration, and temperature were investigated for different cloud-free atmospheric scenarios. It was found that for the tropical scenario a 20% change in humidity has a larger impact than a doubling of the carbon dioxide concentration. The sensitive altitude region for temperature and humidity changes is the entire free troposphere, including the upper troposphere where humidity data quality is poor

Measuring stations for gamma radiation - measured results 1982

International Nuclear Information System (INIS)

Kjelle, P.E.

1983-01-01

Gamma radiation is recorded continuously at 25 stations in Sweden. The evaluation of the data from five of the stations is made in a most accurate way, and the results are presented in this report. (G.B.)

Solar line Lsub(α) profile and an interstellar wind dynamics

International Nuclear Information System (INIS)

Burgin, M.S.

1978-01-01

Analytical theory of interstellar hydrogen atom motion into the region of solar Lsub(α)-radiation is given. Hydrogen distribution in the Solar system is calculated with an account of the Lsub(α) solar line profile difference from a flat one. The effect of the profile form on the scattered radiation intensity is estimated. Calculation errors of the scattered radiation intensity, connected with the difference between a line profile and a flat one, do not exceed 5% for the real Lsub(α) solar line profile

Investigations of aircrews exposure to cosmic radiation - results, conclusions and suggestions

CERN Document Server

Bilski, P; Horwacik, T; Marczewska, B; Ochab, E; Olko, P

2002-01-01

In frame of a research project undertaken in collaboration with Polish airlines LOT, analysis of aircrews exposure to cosmic radiation has been performed. The applied methods included measurements of radiation doses with thermoluminescent detectors (MTS-N, MCP-N) and track detectors (CR-39) and also calculations of route doses with the CARI computer code. The obtained results indicate that aircrews of nearly all airplanes, with exception of these flying only on ATR aircraft, exceed regularly or may exceed in some conditions, effective doses of 1 mSv. In case of Boeing-767 aircrews such exceeding occurs always, independently of solar activity. Investigations revealed, that during these periods of the solar cycle, when intensity of cosmic radiation is high, exceeding of 6 mSv level is also possible. These results indicate, that according to Polish and European regulations it is necessary for airlines to provide regular estimations of radiation exposure of aircrews. Basing on the obtained results a system for pe...

A Research Agenda for Radiation Oncology: Results of the Radiation Oncology Institute’s Comprehensive Research Needs Assessment

International Nuclear Information System (INIS)

Jagsi, Reshma; Bekelman, Justin E.; Brawley, Otis W.; Deasy, Joseph O.; Le, Quynh-Thu; Michalski, Jeff M.; Movsas, Benjamin; Thomas, Charles R.; Lawton, Colleen A.; Lawrence, Theodore S.; Hahn, Stephen M.

2012-01-01

Purpose: To promote the rational use of scarce research funding, scholars have developed methods for the systematic identification and prioritization of health research needs. The Radiation Oncology Institute commissioned an independent, comprehensive assessment of research needs for the advancement of radiation oncology care. Methods and Materials: The research needs assessment used a mixed-method, qualitative and quantitative social scientific approach, including structured interviews with diverse stakeholders, focus groups, surveys of American Society for Radiation Oncology (ASTRO) members, and a prioritization exercise using a modified Delphi technique. Results: Six co-equal priorities were identified: (1) Identify and develop communication strategies to help patients and others better understand radiation therapy; (2) Establish a set of quality indicators for major radiation oncology procedures and evaluate their use in radiation oncology delivery; (3) Identify best practices for the management of radiation toxicity and issues in cancer survivorship; (4) Conduct comparative effectiveness studies related to radiation therapy that consider clinical benefit, toxicity (including quality of life), and other outcomes; (5) Assess the value of radiation therapy; and (6) Develop a radiation oncology registry. Conclusions: To our knowledge, this prioritization exercise is the only comprehensive and methodologically rigorous assessment of research needs in the field of radiation oncology. Broad dissemination of these findings is critical to maximally leverage the impact of this work, particularly because grant funding decisions are often made by committees on which highly specialized disciplines such as radiation oncology are not well represented.

Aesthetic results following partial mastectomy and radiation therapy

International Nuclear Information System (INIS)

Matory, W.E. Jr.; Wertheimer, M.; Fitzgerald, T.J.; Walton, R.L.; Love, S.; Matory, W.E.

1990-01-01

This study was undertaken to determine the aesthetic changes inherent in partial mastectomy followed by radiation therapy in the treatment of stage I and stage II breast cancer. A retrospective analysis of breast cancer patients treated according to the National Surgical Adjuvant Breast Project Protocol B-06 was undertaken in 57 patients from 1984 to the present. The size of mastectomy varied between 2 x 1 cm and 15 x 8 cm. Objective aesthetic outcome, as determined by physical and photographic examination, was influenced primarily by surgical technique as opposed to the effects of radiation. These technical factors included orientation of resections, breast size relative to size of resection, location of tumor, and extent and orientation of axillary dissection. Regarding cosmesis, 80 percent of patients treated in this study judged their result to be excellent or good, in comparison to 50 percent excellent or good as judged by the plastic surgeon. Only 10 percent would consider mastectomy with reconstruction for contralateral disease. Asymmetry and contour abnormalities are far more common than noted in the radiation therapy literature. Patients satisfaction with lumpectomy and radiation, however, is very high. This satisfaction is not necessarily based on objective criteria defining aesthetic parameters, but is strongly influenced by retainment of the breast as an original body part

Radiobiological studies with a series of human cell lines of varying glutathione content

International Nuclear Information System (INIS)

Astor, M.B.

1984-01-01

Radiation responses of a series of four human fibroblast lines obtained from a family affected with 5-oxoprolinuria were determined. Cell suspensions were irradiated under hypoxic conditions and the oxygen enhancement ratio was determined for each cell line. Results are compared with previous studies

Correction of UBV Photometry for Emission Lines

Directory of Open Access Journals (Sweden)

Skopal A.

2003-12-01

Full Text Available We investigate the effect on U,B,V magnitudes of the removal of emission lines from the spectra of some symbiotic stars and novae during their nebular phases. We approach this problem by the precise reconstruction of the composite UV/optical continuum and the line spectrum. The corrections ΔU, ΔB and ΔV are determined from the ratio of fluxes with and without emission lines. We demonstrate the effect for symbiotic nova V1016 Cyg during its nebular phase. We find that about 68%, 78% and 66% of the observed flux in the U, B and V filters is radiated in the emission lines. The effect should be taken into account before using the observed color indices of emission-line objects for diagnosis of their radiation in the continuum.

Preliminary results from the Orbiting Solar Observatory 8 - Observations of optically thin lines

Science.gov (United States)

Shine, R. A.; Roussel-Dupre, D.; Bruner, E. C., Jr.; Chipman, E. G.; Lites, B. W.; Rottman, G. J.; Athay, R. G.; White, O. R.

1976-01-01

The University of Colorado spectrometer aboard OSO 8 has measured the high temperature C IV resonance lines (at 1548 and 1551 A) and the Si IV resonance lines (at 1393 and 1402 A) formed in the solar chromosphere-corona transition region. Preliminary results include studies of mean profiles, a comparison of cell and network profiles, and the behavior of the lines at the extreme solar limb.

Individual radiosensitivity does not correlate with radiation-induced apoptosis in lymphoblastoid cell lines or CD{sup 3+} lymphocytes

Energy Technology Data Exchange (ETDEWEB)

Wistop, A.; Keller, U.; Grabenbauer, G.G.; Sauer, R.; Distel, L.V.R. [Dept. of Radiation Oncology, Friedrich Alexander Univ. Erlangen-Nuremberg, Erlangen (Germany); Sprung, C.N. [Div. of Research, Peter MacCallum Cancer Centre, East Melbourne, VIC (Australia)

2005-05-01

Background and purpose: spontaneous and radiation-induced apoptosis of lymphoblastoid cell lines (LCLs) derived from healthy donors, cancer patients and donors with radiosensitivity syndromes as well as CD{sup 3+} lymphocytes from patients with {>=} grade 3 late toxicity were investigated as a possible marker for the detection of individual radiosensitivity. These investigations are based on the hypothesis that hypersensitive patients have reduced levels of apoptosis after in vitro irradiation as a result of a defect in the signaling pathway. Material and methods: Epstein-Barr virus-(EBV-)transformed LCLs derived from five healthy donors, seven patients with heterozygous or homozygous genotype for ataxia-telangiectasia or Nijmegen breakage syndrome and five patients with {>=} grade 3 late toxicity (RTOG) were investigated. In addition, CD{sup 3+} lymphocytes from 21 healthy individuals and 18 cancer patients including five patients with a proven cellular hypersensitivity to radiation were analyzed. Cells were irradiated in vitro with a dose of 2 and 5 Gy and were incubated for 48 h. Apoptotic rates were measured by the TUNEL assay followed by customized image analysis. Results: four out of seven radiosensitivity syndrome patients were identified to have an increased cellular radiosensitivity as determined by reduced apoptotic rates after irradiation of their respective LCLs. Comparatively, only two of the five hypersensitive cancer patients were clearly identified by reduced apoptotic rates. Spontaneous apoptotic rates were very homogeneous among all 39 samples from controls and patients, while lymphocytes of all cancer patients showed significantly lower radiation-induced rates. Conclusion: only a subgroup of hypersensitive patients may be identified by reduction of radiation-induced apoptotic rate. It is concluded that the hypothesis according to which hypersensitive cells have reduced levels of apoptosis is only conditionally true. The authors suggest that this

Radiation exposure of the aircrew and passengers on some Czechoslovak air lines

International Nuclear Information System (INIS)

Spurny, F.; Michalik, V.; Obraz, O.; Pernicka, F.; Votockova, I.

1993-01-01

According to the ICRP 60 recommendation, the aircrew should be included among workers whose exposure to cosmic radiation is considered to be occupational exposure. This brings about the need for a more precise determination and the mapping of the exposure level on different air routes. The results are presented of measurements performed by the staff of the Institute of Radiation Dosimetry on board of CSA aircraft (TU 154 M and A 310-300 Airbus) in 1991-1992. A number of passive and active devices were used to measure the ionizing and neutron component of cosmic radiation. The results obtained confirm the basic ideas about the influence of various factors on the exposure level. The interpretation of data is discussed in detail, particularly with respect to its possible modification based on new data on particle spectra on board of subsonic civil transport aircraft. (author) 2 tabs., 4 figs., 24 refs

Radiation related basic cancer research : research for radiation induced tumor cell killing

International Nuclear Information System (INIS)

Lee, Seung Hoon; Hong, Seok Il; Cho, Kyung Ja; Kim, Byung Gi; Lee, Kee Ho; Nam, Myung Jin

1999-04-01

The radioresistant clones was established from human U251 glioblastoma cell line through intermittently exposed to 3 Gy gamma-radiation for six months. Treatment of SNU-16 cells with various doses of radiation, TNF alpha and PMA resulted in a decrease in cell viability. The results prove that cell death of SNU16 is a apoptosis mediated by caspase-3. We have examined the expression of bcl-2 and c-myc in cervical cancer specimens and cervical intraepithelial neoplasia (CIN) to determine the role of coexpression of bcl-3 and c-myc during progression into cervical cancer. The frequent alterations in FHIT expression in many cervical carcinomas and their cell lines suggest that FHIT gene alterations are pla a role in cervical tumorigenesis. According to these correlation between the viability and apoptosis of RD cells, the proper range of the dosage for the investigation of differentiation potency in RD cells was assessed as 1 to 3Gy

Radiation related basic cancer research : research for radiation induced tumor cell killing

Energy Technology Data Exchange (ETDEWEB)

Lee, Seung Hoon; Hong, Seok Il; Cho, Kyung Ja; Kim, Byung Gi; Lee, Kee Ho; Nam, Myung Jin

1999-04-01

The radioresistant clones was established from human U251 glioblastoma cell line through intermittently exposed to 3 Gy gamma-radiation for six months. Treatment of SNU-16 cells with various doses of radiation, TNF alpha and PMA resulted in a decrease in cell viability. The results prove that cell death of SNU16 is a apoptosis mediated by caspase-3. We have examined the expression of bcl-2 and c-myc in cervical cancer specimens and cervical intraepithelial neoplasia (CIN) to determine the role of coexpression of bcl-3 and c-myc during progression into cervical cancer. The frequent alterations in FHIT expression in many cervical carcinomas and their cell lines suggest that FHIT gene alterations are pla a role in cervical tumorigenesis. According to these correlation between the viability and apoptosis of RD cells, the proper range of the dosage for the investigation of differentiation potency in RD cells was assessed as 1 to 3Gy.

Spectral measurements of gamma radiation streaming through ducts

International Nuclear Information System (INIS)

Meenakshisundaram, P.K.; Bhatnagar, V.M.; Raghunath, V.M.; Gopinath, D.V.

1979-01-01

The paper presents the spectral measurements of gamma radiation streaming through multi-legged rectangular concrete ducts for cesium-137 and cobald-60 sources. Effect of lead lining the inner surface of the duct on the streaming radiation spectrum and optimization of liner thickness for minimum streaming radiation dose have been studied. For three-legged ducts, a comparative analysis of lead lining the entire duct as against lining any one or both the corners of the duct is reported. It is seen that lead lining any one of the corners would reduce the streaming radiation dose by a factor of 5 to 12. Lining both the corners which is nearly as effective as lining the entire duct reduces the dose by a factor of 16 to 60 depending on the soruce energy and duct dimensions. (orig.)

Study of the cell cycle control for human malignant mesothelioma lines. Interferon and radiations effect; Etude de la regulation du cycle cellulaire de lignees de mesotheliome malin humain. Effet de l'interferon et des radiations

Energy Technology Data Exchange (ETDEWEB)

Vivo, C

1999-07-01

In order to better understand the inhibition mechanisms of the IFN-R-HU on tumoral development, the IFN-R-U effect on MM lines has been studied. Three groups of lines has been distinguished: eight sensitive lines, two intermediate and three resistant. The sensitive lines showed a triple locking of the cell cycle: in phases S, G1 and G2. The study of the cell cycle control points function, realized by the MM lines radiation exposure showed the points function on G1/S and-or on G2/M and the dependence or non dependence of the cycle stop of the protein P53 and P21 W at F1/CIP1. (A.L.B.)

Stability of emission line clouds in active galactic nuclei

International Nuclear Information System (INIS)

Krinsky, I.S.

1989-01-01

A numerical model was developed for a Quasar Stellar Object (QSO) broad emission line cloud (ELC) imbedded within a confining hot intercloud medium (HIM) for the purpose of studying its stability to perturbations in its temperature and density. A self-consistent model in radiative, pressure and thermal equilibrium is presented. The effect of trapped line radiation pressure is also included with the total pressure (particle plus radiation) held constant. The equilibrium model is found to have regions with radiation pressure exceeding gas pressure. Energy transport includes the effects of an external broken power law continuum and thermal conduction of heat from the HIM. Conduction is found to be unimportant to the total energy budget of the cloud, but is important to the dynamics of the ELC/HIM interface. Independent of the ELC/HIM model, an extension of second order probabilistic radiative transfer that treats the diffuse radiation field as composed of two oppositely directed streams is presented. The high ionization zone of the ELC is found to be unstable to radiatively driven sound waves. Both the external radiation field and the force of trapped line radiation are potential sources for driving the growth of sound waves. The final picture that emerges is that the ELC must be in a constant state of flux

Coherent radiation from pulsars

International Nuclear Information System (INIS)

Cox, J.L. Jr.

1979-01-01

Interaction between a relativistic electrom stream and a plasma under conditions believed to exist in pulsar magnetospheres is shown to result in the simultaneous emission of coherent curvature radiation at radio wavelengths and incoherent curvature radiation at X-ray wavelengths from the same spatial volume. It is found that such a stream can propagate through a plasma parallel to a very strong magnetic field only if its length is less than a critical length L/sub asterisk/ic. Charge induced in the plasma by the stream co-moves with the stream and has the same limitation in longitudinal extent. The resultant charge bunching is sufficient to cause the relatively low energy plasma particles to radiate at radio wavelengths coherently while the relatively high energy stream particles radiate at X-ray wavelengths incoherently as the stream-plasma system moves along curved magnetic field lines. The effective number of coherently radiating particles per bunch is estimated to be approx.10 14 --10 15 for a tupical pulsar

NEW Fe IX LINE IDENTIFICATIONS USING SOLAR AND HELIOSPHERIC OBSERVATORY/SOLAR ULTRAVIOLET MEASUREMENT OF EMITTED RADIATION AND HINODE/EIS JOINT OBSERVATIONS OF THE QUIET SUN

International Nuclear Information System (INIS)

Landi, E.; Young, P. R.

2009-01-01

In this work, we study joint observations of Hinode/EUV Imaging Spectrometer (EIS) and Solar and Heliospheric Observatory/Solar Ultraviolet Measurement of Emitted Radiation of Fe IX lines emitted by the same level of the high energy configuration 3s 2 3p 5 4p. The intensity ratios of these lines are dependent on atomic physics parameters only and not on the physical parameters of the emitting plasma, so that they are excellent tools to verify the relative intensity calibration of high-resolution spectrometers that work in the 170-200 A and 700-850 A wavelength ranges. We carry out extensive atomic physics calculations to improve the accuracy of the predicted intensity ratio, and compare the results with simultaneous EIS-SUMER observations of an off-disk quiet Sun region. We were able to identify two ultraviolet lines in the SUMER spectrum that are emitted by the same level that emits one bright line in the EIS wavelength range. Comparison between predicted and measured intensity ratios, wavelengths and energy separation of Fe IX levels confirms the identifications we make. Blending and calibration uncertainties are discussed. The results of this work are important for cross-calibrating EIS and SUMER, as well as future instrumentation.

EUV lines observed with EIS/Hinode in a solar prominence

Science.gov (United States)

Labrosse, N.; Schmieder, B.; Heinzel, P.; Watanabe, T.

2011-07-01

Context. During a multi-wavelength observation campaign with Hinode and ground-based instruments, a solar prominence was observed for three consecutive days as it crossed the western limb of the Sun in April 2007. Aims: We report on observations obtained on 26 April 2007 using EIS (Extreme ultraviolet Imaging Spectrometer) on Hinode. They are analysed to provide a qualitative diagnostic of the plasma in different parts of the prominence. Methods: After correcting for instrumental effects, the rasters at different wavelengths are presented. Several regions within the same prominence are identified for further analysis. Selected profiles for lines with formation temperatures between log (T) = 4.7 and log (T) = 6.3, as well as their integrated intensities, are given. The profiles of coronal, transition region, and He ii lines are discussed. We pay special attention to the He ii line, which is blended with coronal lines. Results: Some quantitative results are obtained by analysing the line profiles. They confirm that depression in EUV lines can be interpreted in terms of two mechanisms: absorption of coronal radiation by the hydrogen and neutral helium resonance continua, and emissivity blocking. We present estimates of the He ii line integrated intensity in different parts of the prominence according to different scenarios for the relative contribution of absorption and emissivity blocking to the coronal lines blended with the He ii line. We estimate the contribution of the He ii 256.32 Å line to the He ii raster image to vary between ~44% and 70% of the raster's total intensity in the prominence according to the different models used to take into account the blending coronal lines. The inferred integrated intensities of the He ii 256 Å line are consistent with the theoretical intensities obtained with previous 1D non-LTE radiative transfer calculations, yielding a preliminary estimate of the central temperature of 8700 K, a central pressure of 0.33 dyn cm-2, and a

Prone Breast Intensity Modulated Radiation Therapy: 5-Year Results

International Nuclear Information System (INIS)

Osa, Etin-Osa O.; DeWyngaert, Keith; Roses, Daniel; Speyer, James; Guth, Amber; Axelrod, Deborah; Fenton Kerimian, Maria; Goldberg, Judith D.; Formenti, Silvia C.

2014-01-01

Purpose: To report the 5-year results of a technique of prone breast radiation therapy delivered by a regimen of accelerated intensity modulated radiation therapy with a concurrent boost to the tumor bed. Methods and Materials: Between 2003 and 2006, 404 patients with stage I-II breast cancer were prospectively enrolled into 2 consecutive protocols, institutional trials 03-30 and 05-181, that used the same regimen of 40.5 Gy/15 fractions delivered to the index breast over 3 weeks, with a concomitant daily boost to the tumor bed of 0.5 Gy (total dose 48 Gy). All patients were treated after segmental mastectomy and had negative margins and nodal assessment. Patients were set up prone: only if lung or heart volumes were in the field was a supine setup attempted and chosen if found to better spare these organs. Results: Ninety-two percent of patients were treated prone, 8% supine. Seventy-two percent had stage I, 28% stage II invasive breast cancer. In-field lung volume ranged from 0 to 228.27 cm 3 , mean 19.65 cm 3 . In-field heart volume for left breast cancer patients ranged from 0 to 21.24 cm 3 , mean 1.59 cm 3 . There was no heart in the field for right breast cancer patients. At a median follow-up of 5 years, the 5-year cumulative incidence of isolated ipsilateral breast tumor recurrence was 0.82% (95% confidence interval [CI] 0.65%-1.04%). The 5-year cumulative incidence of regional recurrence was 0.53% (95% CI 0.41%-0.69%), and the 5-year overall cumulative death rate was 1.28% (95% CI 0.48%-3.38%). Eighty-two percent (95% CI 77%-85%) of patients judged their final cosmetic result as excellent/good. Conclusions: Prone accelerated intensity modulated radiation therapy with a concomitant boost results in excellent local control and optimal sparing of heart and lung, with good cosmesis. Radiation Therapy Oncology Group protocol 1005, a phase 3, multi-institutional, randomized trial is ongoing and is evaluating the equivalence of a similar dose and fractionation

Prone Breast Intensity Modulated Radiation Therapy: 5-Year Results

Energy Technology Data Exchange (ETDEWEB)

Osa, Etin-Osa O.; DeWyngaert, Keith [Department of Radiation Oncology, New York University School of Medicine, New York, New York (United States); Roses, Daniel [Department of Surgery, New York University School of Medicine, New York, New York (United States); Speyer, James [Department of Medical Oncology, New York University School of Medicine, New York, New York (United States); Guth, Amber; Axelrod, Deborah [Department of Surgery, New York University School of Medicine, New York, New York (United States); Fenton Kerimian, Maria [Department of Radiation Oncology, New York University School of Medicine, New York, New York (United States); Goldberg, Judith D. [Department of Population Health, New York University School of Medicine, New York, New York (United States); Formenti, Silvia C., E-mail: Silvia.formenti@nyumc.org [Department of Radiation Oncology, New York University School of Medicine, New York, New York (United States)

2014-07-15

Purpose: To report the 5-year results of a technique of prone breast radiation therapy delivered by a regimen of accelerated intensity modulated radiation therapy with a concurrent boost to the tumor bed. Methods and Materials: Between 2003 and 2006, 404 patients with stage I-II breast cancer were prospectively enrolled into 2 consecutive protocols, institutional trials 03-30 and 05-181, that used the same regimen of 40.5 Gy/15 fractions delivered to the index breast over 3 weeks, with a concomitant daily boost to the tumor bed of 0.5 Gy (total dose 48 Gy). All patients were treated after segmental mastectomy and had negative margins and nodal assessment. Patients were set up prone: only if lung or heart volumes were in the field was a supine setup attempted and chosen if found to better spare these organs. Results: Ninety-two percent of patients were treated prone, 8% supine. Seventy-two percent had stage I, 28% stage II invasive breast cancer. In-field lung volume ranged from 0 to 228.27 cm{sup 3}, mean 19.65 cm{sup 3}. In-field heart volume for left breast cancer patients ranged from 0 to 21.24 cm{sup 3}, mean 1.59 cm{sup 3}. There was no heart in the field for right breast cancer patients. At a median follow-up of 5 years, the 5-year cumulative incidence of isolated ipsilateral breast tumor recurrence was 0.82% (95% confidence interval [CI] 0.65%-1.04%). The 5-year cumulative incidence of regional recurrence was 0.53% (95% CI 0.41%-0.69%), and the 5-year overall cumulative death rate was 1.28% (95% CI 0.48%-3.38%). Eighty-two percent (95% CI 77%-85%) of patients judged their final cosmetic result as excellent/good. Conclusions: Prone accelerated intensity modulated radiation therapy with a concomitant boost results in excellent local control and optimal sparing of heart and lung, with good cosmesis. Radiation Therapy Oncology Group protocol 1005, a phase 3, multi-institutional, randomized trial is ongoing and is evaluating the equivalence of a similar dose and

Pathogenesis of acute radiation effects in the urinary bladder. Experimental results

International Nuclear Information System (INIS)

Doerr, W.; Eckhardt, M.; Ehme, A.; Koi, S.

1998-01-01

Purpose: The present review summarizes experimental studies of the pathogenesis of acute radiation-induced changes in urinary bladder function. Material and methods: Transurethral cystometry was used for longitudinal assessment of bladder function in mice. With this technique, radiation-induced changes in storage capacity can be quantified. In histological studies, changes in urothelial cell density and in urothelial protein expression during the acute radiation response were determined. Acetylsalicylic acid (ASA) was used for the treatment of acute functional changes. Results: The histological studies did not reveal any systematic fluctuations in urothelial cell density during the time of the acute radiation response. However, characteristic changes in the expression of proteins associated with urothelial cell function, differentiation and cell contact were observed, which correlated with the functional impairment. By local or systemical application of ASA, a significant restoration of bladder function compared to placebo treatment could be achieved. Conclusion: Acute functional radiation effects in the urinary bladder are not based on urothelial denudation. However, changes in protein expression indicate an impairment of the urothelial barrier function. The results of ASA treatment demonstrate that prostaglandins are involved in the response. Alterations in urothelial or endothelial prostaglandin metabolism may be primarily radiation-induced or secondary because of the impaired urothelial barrier. (orig.) [de

Assessment of radiation risks as a result of the Chernobyl accident

International Nuclear Information System (INIS)

Ivanov, V.K.

1998-01-01

Full text of publication follows: the Government of the former USSR had made decision on establishing common registry of exposed persons in several months after the Chernobyl accident. The registry had served in Medical Radiological Research Centre of Russian Academy of Medical Sciences, Obninsk City till 1992 (the time of dissolution of the USSR). Individual medical and dosimetric information on 659292 persons, including 284907 emergency accident workers (liquidators) had been collected for the period between 1986 and 1991. As of 01.01.1998, National Chernobyl Registry of the Russian Federation has kept individual data on 508236 persons including 167726 liquidators. As it is known, long-term epidemiological study of Hiroshima and Nagasaki A-bomb survivors resulted in statistically significant assessments of radiation risks for induction of cancer at the dose level above 0.5 Gy. Radiation doses after the Chernobyl accident do not exceed 0.3-0.5 Gy. That is why assessment of radiation risks at low radiation doses is a problem of great importance. As a result of the epidemiological studies performed on the basis of the Russian Chernobyl registry we pioneered the assessment of statistically significant radiation risks for induction of cancer at low radiation dose. (author)

Radiation therapy in old patients. Side effects and results of radiation therapy in old patients

International Nuclear Information System (INIS)

Geinitz, H.; Zimmermann, F.B.; Molls, M.

1999-01-01

Background: Despite a growing number of elderly patients receiving radiation therapy little is known about side effects and outcome of irradiation in this section of the population. Methods: In a review article epidemiologic data, aspects of radiation-biology as well as side effects and outcome of radiation therapy of elderly patients are discussed. Results: Cancer incidence rises with age and is exceeding 3.5% for males older than 85 years. With a life expectancy of more than 4 years, curative therapy is indicated even at this age. Furthermore, several retrospective studies indicate that local control and disease-Specific survival after radiation therapy of elderly patients is comparable with that of younger persons. The exception contains elderly patients with grade-III to IV gliomas or with rectal carcinoma who show a reduced survival which is perhaps caused by less aggressive combined treatment (tumor resection). Although some biological and molecular data indicate a rise in radiation sensitivity with growing age like the reduction of the capacity of some DNA-repair enzymes, there is no convincing evidence in animal studies or in retrospective clinical studies that radiation therapy is generally less well tolerated by older individuals. Some age-depending differences in organ toxicities are described in 3 large studies, which evaluate the data of patients who were enrolled in different EORTC-trials: Older patients suffer more of functional mucositis in case of radiation therapy to the head and neck, they have an increased weight loss and a higher frequency of late esophageal damage when irradiated in the thorax, and they show a higher prevalence of sexual dysfunction when treated with radiation therapy to the pelvis. On the other hand younger patients suffer more from acute toxicity like skin damage, nausea, and deterioration of the performance status during pelvic radiotherapy. When discussing the dose intensity of radiation therapy concomitant disease which

Genetic determination of the biological radiation response in inbred mice lines; Genetische Determination der biologischen Strahlenantwort in Mausinzuchtstaemmen

Energy Technology Data Exchange (ETDEWEB)

Gomolka, M.; Hornhardt, S.; Jung, T. [Bundesamt fuer Strahlenschutz Oberschleissheim (Germany). Institut fuer Strahlenhygiene

2000-07-01

Variation in radiation sensitivity and radiation resistance is influenced by the genetic constitution of an individual. Loss of function of genes involved in DNA repair, cell cycle or controlled cell death can have serious consequences on individual radiation sensitivity. For example, individuals suffering on the clinical syndrome of Ataxia telangiectasia exhibit radiation sensitivity in the order of 2-3 magnitudes higher than other cancer patients. For radiation protection it is important to clarify the role of genetic predisposition for radiation sensitivity in clinical healthy people. Therefore, data were collected from the literature describing the genetic variation (heritability) of radiation sensitivity in the mouse model. A heritability of 30-50% was calculated for 27 inbred mice lines by Roderick (1963) based on days of survival after a daily dose of 1 Gy {gamma}-irradiation. The following inbred lines were described in the literature as radiation sensitive (phenotypical markers were e.g., time of survival, mortality, reduction in fertility post exposure): SWR, RIII, NC, K, HLG, DBA, CBA, BALB/c, A, AKR. Radiation resistance was demonstrated in SJL, SEC, RF, MA, C58, C57BR, BDP and 129. Parameter of longevity, some physiological, biochemical and immunological parameters as given in the data bank of the Jackson Laboratory, U.S.A., were compared between radiation sensitive and radiation resistant inbred strains. No correlation was seen for the most of the parameters except for the development of breast cancer. In 6 out of 10 radiosensitive inbred strains breast cancer is described while only 1 of 8 strains exhibits breast cancer. The higher heritability of 30-50% in spite of a very complex phenotype like survival and the correlation between radiosensitivity and tumour incidence show that individual genetic susceptibility is important on the biological radiation reaction. (orig.) [German] Die phaenotypische Variation der Strahlensensitivitaet und

Radiation damage at LHCb, results and expectations

CERN Multimedia

Faerber, Christian

2011-01-01

The LHCb Detector is a single-arm spectrometer at the LHC designed to detect new physics through measuring CP violation and rare decays of heavy flavor mesons. The detector consists of vertex detector, tracking system, dipole magnet, 2 RICH detectors, em. calorimeter, hadron calorimeter, muon detector which all use different technologies and suffer differently from radiation damage. These radiation damage results and the investigation methods will be shown. The delivered luminosity till July 2011 was about 450 pb−1. The Vertex detector receives the highest particle flux at LHCb. The currents drawn by the silicon sensors are, as expected, increasing proportional to the integrated luminosity. The highest irradiaton regions of the n-bulk silicon sensors are observed to have recently undergone space charge sign inversion. The Silicon Trackers show increasing leakage currents comparable with earlier predictions. The electromagentic calorimeter and hadron calorimeter suffer under percent-level signal decrease whi...

LINE FORMATION IN SPECTRA OF X-RAY NOVAE

OpenAIRE

Suleimanov, V. F.; Shimansky, V. V.

2017-01-01

Results of X-ray Novae (XN) optical spectra computation are presented. The continuum and Balmer line are calculated. The model of XN as a self-irradiated accretion disk is used. Local (for given radius) disk atmospheres as model stellar atmospheres, heated due to external X-ray radiation are treated. Changes of spectra shape and equivalent widths of the Balmer lines depending from the luminosity and some others accretion disk parameters are investigated. The comparison of GRO JO422+32 observe...

Intrinsic radiation resistance in human chondrosarcoma cells

International Nuclear Information System (INIS)

Moussavi-Harami, Farid; Mollano, Anthony; Martin, James A.; Ayoob, Andrew; Domann, Frederick E.; Gitelis, Steven; Buckwalter, Joseph A.

2006-01-01

Human chondrosarcomas rarely respond to radiation treatment, limiting the options for eradication of these tumors. The basis of radiation resistance in chondrosarcomas remains obscure. In normal cells radiation induces DNA damage that leads to growth arrest or death. However, cells that lack cell cycle control mechanisms needed for these responses show intrinsic radiation resistance. In previous work, we identified immortalized human chondrosarcoma cell lines that lacked p16 ink4a , one of the major tumor suppressor proteins that regulate the cell cycle. We hypothesized that the absence of p16 ink4a contributes to the intrinsic radiation resistance of chondrosarcomas and that restoring p16 ink4a expression would increase their radiation sensitivity. To test this we determined the effects of ectopic p16 ink4a expression on chondrosarcoma cell resistance to low-dose γ-irradiation (1-5 Gy). p16 ink4a expression significantly increased radiation sensitivity in clonogenic assays. Apoptosis did not increase significantly with radiation and was unaffected by p16 ink4a transduction of chondrosarcoma cells, indicating that mitotic catastrophe, rather than programmed cell death, was the predominant radiation effect. These results support the hypothesis that p16 ink4a plays a role in the radiation resistance of chondrosarcoma cell lines and suggests that restoring p16 expression will improve the radiation sensitivity of human chondrosarcomas

Anisotropic ionizing radiation in Seyfert galaxies. I - The extended narrow-line region in Markarian 573

Science.gov (United States)

Tsvetanov, Zlatan; Walsh, J. R.

1992-01-01

The morphology, kinematics, and ionization state of the nuclear extended narrow-line region (ENLR) of the Seyfert 2 galaxy Mrk 573 are studied using narrow-band images of a grid of long-slit spectra. The entire ENLR is mapped spectroscopically, and velocity structure is studied. The velocity field map shows a typical galactic rotation picture with some important deviations. A simple geometric model, in accordance with the 'unified schemes', is employed to study the effects of various parameters of the observed picture. The best match is achieved when a biconical radiation field illuminates the ISM of the host galaxy that takes part in a normal galaxy rotation but also has radial motions close to the nucleus. The emission-line images reveal an ENLR elongated along the radio axis in the northwest-southeast direction, but a map of the flux ratio forbidden O III 5007/(H-alpha + forbidden N II) shows a different structure, with the highest excitation peak offset by about 4 arcsec along the radio axis to the southeast.

Dielectric image line groove antennas for millimeterwaves

Science.gov (United States)

Solbach, K.; Wolff, I.

Grooves in the ground plane of dielectric image lines are proposed as a new radiating structure. A figure is included showing the proposed groove structure as a discontinuity in a dielectric image line. A wave incident on the dielectric image line is partly reflected by the discontinuity, partly transmitted across the groove, and partly radiated into space above the line. In a travelling-wave antenna, a number of grooves are arranged below a dielectric guide, with spacings around one guide wavelength to produce a beam in the upper half space. A prescribed aperture distribution can be effected by tapering the series radiation resistance of the grooves. This can be done by adjusting the depths of the grooves with a constant width or by varying the widths of the grooves with a constant depth. Attention is also given to circular grooves. Here, the widths of the holes are chosen so that they can be considered as waveguides operating far below the cut-off frequency of the fundamental circular waveguide mode.

A novel radiation-induced p53 mutation is not implicated in radiation resistance via a dominant-negative effect.

Directory of Open Access Journals (Sweden)

Yunguang Sun

Full Text Available Understanding the mutations that confer radiation resistance is crucial to developing mechanisms to subvert this resistance. Here we describe the creation of a radiation resistant cell line and characterization of a novel p53 mutation. Treatment with 20 Gy radiation was used to induce mutations in the H460 lung cancer cell line; radiation resistance was confirmed by clonogenic assay. Limited sequencing was performed on the resistant cells created and compared to the parent cell line, leading to the identification of a novel mutation (del at the end of the DNA binding domain of p53. Levels of p53, phospho-p53, p21, total caspase 3 and cleaved caspase 3 in radiation resistant cells and the radiation susceptible (parent line were compared, all of which were found to be similar. These patterns held true after analysis of p53 overexpression in H460 cells; however, H1299 cells transfected with mutant p53 did not express p21, whereas those given WT p53 produced a significant amount, as expected. A luciferase assay demonstrated the inability of mutant p53 to bind its consensus elements. An MTS assay using H460 and H1299 cells transfected with WT or mutant p53 showed that the novel mutation did not improve cell survival. In summary, functional characterization of a radiation-induced p53 mutation in the H460 lung cancer cell line does not implicate it in the development of radiation resistance.

A line driven Rayleigh-Taylor-type instability in hot stars

International Nuclear Information System (INIS)

Nelson, G.D.; Hearn, A.G.

1978-01-01

The existence of a Rayleigh-Taylor-type instability in the atmosphere of hot stars, driven by the radiative force associated with impurity ion resonance lines, is demonstrated. In a hot star with an effective temperature of 50 000 K, the instability will grow exponentially with a time scale of approximately 50 s in the layers where the stellar wind velocity is 5% of the thermal velocity of the ion. As a result, radially symmetric stellar winds driven by resonance line radiative forces will break up in small horizontal scale lengths. The energy fed into the instability provides a possible source of mechanical heating in the atmosphere for a chromosphere or corona. (orig.) [de

Radiation degradation of polymethacrylamide

International Nuclear Information System (INIS)

O'Connor, D.J.

1984-01-01

The effects of radiation on polymers have been studied for many years. When polymers are subjected to ultraviolet light or ionizing radiation, chain scission and crosslinking are possible. The radiation degradations of several methacrylate type polymers were investigated. The primary polymer studied was polymethacrylamide (PMAAm). Ultraviolet irradiated PMAAm yielded a five line ESR spectrum with 22 gauss splitting which is believed to arise from a polymeric radical ending with a methacrylamide unit. The results obtained indicate that polymethacrylamide is a polymer which undergoes main chain cleavage upon irradiation. As such this polymer may have potential applicability as a positive resist for fabrication of microelectronic devices

Recent results on the development of radiation-hard diamond detectors

CERN Document Server

Conway, J S; Bauer, C; Berdermann, E; Bergonzo, P; Bogani, F; Borchi, E; Brambilla, A; Bruzzi, Mara; Colledani, C; Dabrowski, W; Da Graca, J; Delpierre, P A; Deneuville, A; Dulinski, W; van Eijk, B; Fallou, A; Fizzotti, F; Foulon, F; Friedl, M; Gan, K K; Gheeraert, E; Grigoriev, E; Hallewell, G D; Hall-Wilton, R; Han, S; Hartjes, F G; Hrubec, Josef; Husson, D; Jamieson, D; Kagan, H; Kania, D R; Kaplon, J; Karl, C; Kass, R; Knöpfle, K T; Krammer, Manfred; Lo Giudice, A; Lü, R; Manfredi, P F; Manfredotti, C; Marshall, R D; Meier, D; Mishina, M; Oh, A; Pan, L S; Palmieri, V G; Pernicka, Manfred; Peitz, A; Pirollo, S; Plano, R; Polesello, P; Prawer, S; Pretzl, Klaus P; Procario, M; Re, V; Riester, J L; Roe, S; Roff, D G; Rudge, A; Russ, J; Schnetzer, S; Sciortino, S; Somalwar, S V; Speziali, V; Stelzer, H; Stone, R; Suter, B; Tapper, R J; Tesarek, R; Thomson, G B; Trawick, M; Trischuk, W; Vittone, E; Walsh, A M; Wedenig, R; Weilhammer, Peter; White, C; Ziock, H J; Zöller, M

1999-01-01

Charged particle detectors made from chemical vapor deposition (CVD) diamond have radiation hardness greatly exceeding that of silicon- based detectors. The CERN-based RD42 Collaboration has developed and tested CVD diamond microstrip and pixel detectors with an eye to their application in the intense radiation environment near the interaction region of hadron colliders. This paper presents recent results from tests of these detectors. (4 refs).

Induced mutation in rice by in-vitro radiation

International Nuclear Information System (INIS)

Qi Xiufang; Zhao Chengzhang; Zhen Kangle

1989-01-01

The experiment indicated the adequate dose and growth stage for in-vitro radiation treatment. The results were: 1) Effect of 137 Cs-γ rays on redifferentiation and rate of green plantlets of somatic cells at different growth stage is different. The sequence of effect is callus>callus with green spots>callus with green shoot>mature embryo of dry seed. 2) The fertility of regenerated rice plants decreased with the radiation dose from 0 to 2.58 C/kg, and the rate of exserted stigma increased. 3) The occurence with early maturity increased up to 3.8%, among with about 0.5% of the plant lines matured 15 days earlier. 4) Tow male sterile lines with extruded stigmas were obtained, whose plant heights were reduced. Its frequency of occurance by in-vitro radiation is more than by coventional radiation and somatic cell culture

Transition radiation in metal-metal multilayer nanostructures as a medical source of hard x-ray radiation

International Nuclear Information System (INIS)

Pokrovsky, A. L.; Kaplan, A. E.; Shkolnikov, P. L.

2006-01-01

We show that a periodic metal-metal multilayer nanostructure can serve as an efficient source of hard x-ray transition radiation. Our research effort is aimed at developing an x-ray source for medical applications, which is based on using low-energy relativistic electrons. The approach toward choosing radiator-spacer couples for the generation of hard x-ray resonant transition radiation by few-MeV electrons traversing solid multilayer structures for the energies of interest to medicine (30-50 keV) changes dramatically compared with that for soft x-ray radiation. We show that one of the main factors in achieving the required resonant line is the absence of the contrast of the refractive indices between the spacer and the radiator at the far wings of the radiation line; for that purpose, the optimal spacer, as a rule, should have a higher atomic number than the radiator. Having experimental goals in mind, we have considered also the unwanted effects due to bremsstrahlung radiation, absorption and scattering of radiated photons, detector-related issues, and inhibited coherence of transition radiation due to random deviation of spacing between the layers. Choosing as a model example a Mo-Ag radiator-spacer pair of materials, we demonstrate that the x-ray transition radiation line can be well resolved with the use of spatial and frequency filtering

SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: Fourth Results Report

Energy Technology Data Exchange (ETDEWEB)

Eudy, L.; Chandler, K.

2013-01-01

SunLine Transit Agency, which provides public transit services to the Coachella Valley area of California, has demonstrated hydrogen and fuel cell bus technologies for more than 10 years. In May 2010, SunLine began demonstrating the advanced technology (AT) fuel cell bus with a hybrid electric propulsion system, fuel cell power system, and lithium-based hybrid batteries. This report describes operations at SunLine for the AT fuel cell bus and five compressed natural gas buses. The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) is working with SunLine to evaluate the bus in real-world service to document the results and help determine the progress toward technology readiness. NREL has previously published three reports documenting the operation of the fuel cell bus in service. This report provides a summary of the results with a focus on the bus operation from February 2012 through November 2012.

Radiation-induced gene expression in human subcutaneous fibroblasts is predictive of radiation-induced fibrosis

DEFF Research Database (Denmark)

Rødningen, Olaug Kristin; Børresen-Dale, Anne-Lise; Alsner, Jan

2008-01-01

BACKGROUND AND PURPOSE: Breast cancer patients show a large variation in normal tissue reactions after ionizing radiation (IR) therapy. One of the most common long-term adverse effects of ionizing radiotherapy is radiation-induced fibrosis (RIF), and several attempts have been made over the last...... years to develop predictive assays for RIF. Our aim was to identify basal and radiation-induced transcriptional profiles in fibroblasts from breast cancer patients that might be related to the individual risk of RIF in these patients. MATERIALS AND METHODS: Fibroblast cell lines from 31 individuals......-treated fibroblasts. Transcriptional differences in basal and radiation-induced gene expression profiles were investigated using 15K cDNA microarrays, and results analyzed by both SAM and PAM. RESULTS: Sixty differentially expressed genes were identified by applying SAM on 10 patients with the highest risk of RIF...

Amdel on-line analyser at Rooiberg Tin Limited

International Nuclear Information System (INIS)

Owen, T.V.

1987-01-01

An Amdel on line analysis system was installed on the 'A' mine tin flotation plant at Rooiberg in April 1984. The motivation for the installation was made on account of the large variations in the feed grade to the plant and the resulting need for rapid operational adjustments to control concentrate grades thereby maximising the financial returns. An 'on-line' analyser system presented itself as a suitable alternative to the existing control method of smaller laboratory x-ray fluorescence analysers. On the system as installed at Rooiberg, two probes were fitted in each analysis zone, viz a density probe using high energy gamma radiation from a Cesium 127 source and a specific element absorption probe using low energy gamma radiation from a Americium 241 source. The signals as received from the probes are fed to a line receiver unit in the control room where a micro computer is doing the processing and prints out the information as required. Several advantages of this type of installation were gained at Rooiberg Tin Limited

Low Simulated Radiation Limit for Runaway Greenhouse Climates

Science.gov (United States)

Goldblatt, Colin; Robinson, Tyler D.; Zahnle, Kevin J.; Crisp, David

2013-01-01

Terrestrial planet atmospheres must be in long-term radiation balance, with solar radiation absorbed matched by thermal radiation emitted. For hot moist atmospheres, however, there is an upper limit on the thermal emission which is decoupled from the surface temperature. If net absorbed solar radiation exceeds this limit the planet will heat uncontrollably, the so-called \\runaway greenhouse". Here we show that a runaway greenhouse induced steam atmosphere may be a stable state for a planet with the same amount of incident solar radiation as Earth has today, contrary to previous results. We have calculated the clear-sky radiation limits at line-by-line spectral resolution for the first time. The thermal radiation limit is lower than previously reported (282 W/sq m rather than 310W/sq m) and much more solar radiation would be absorbed (294W/sq m rather than 222W/sq m). Avoiding a runaway greenhouse under the present solar constant requires that the atmosphere is subsaturated with water, and that cloud albedo forcing exceeds cloud greenhouse forcing. Greenhouse warming could in theory trigger a runaway greenhouse but palaeoclimate comparisons suggest that foreseeable increases in greenhouse gases will be insufficient to do this.

A Research Agenda for Radiation Oncology: Results of the Radiation Oncology Institute's Comprehensive Research Needs Assessment

Energy Technology Data Exchange (ETDEWEB)

Jagsi, Reshma, E-mail: rjagsi@med.umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Bekelman, Justin E. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States); Brawley, Otis W. [Department of Hematology and Oncology, Emory University, and American Cancer Society, Atlanta, Georgia (United States); Deasy, Joseph O. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Le, Quynh-Thu [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Michalski, Jeff M. [Department of Radiation Oncology, Washington University, St. Louis, MO (United States); Movsas, Benjamin [Department of Radiation Oncology, Henry Ford Health System, Detroit, MI (United States); Thomas, Charles R. [Department of Radiation Oncology, Oregon Health and Sciences University, Portland, OR (United States); Lawton, Colleen A. [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Lawrence, Theodore S. [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Hahn, Stephen M. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States)

2012-10-01

Purpose: To promote the rational use of scarce research funding, scholars have developed methods for the systematic identification and prioritization of health research needs. The Radiation Oncology Institute commissioned an independent, comprehensive assessment of research needs for the advancement of radiation oncology care. Methods and Materials: The research needs assessment used a mixed-method, qualitative and quantitative social scientific approach, including structured interviews with diverse stakeholders, focus groups, surveys of American Society for Radiation Oncology (ASTRO) members, and a prioritization exercise using a modified Delphi technique. Results: Six co-equal priorities were identified: (1) Identify and develop communication strategies to help patients and others better understand radiation therapy; (2) Establish a set of quality indicators for major radiation oncology procedures and evaluate their use in radiation oncology delivery; (3) Identify best practices for the management of radiation toxicity and issues in cancer survivorship; (4) Conduct comparative effectiveness studies related to radiation therapy that consider clinical benefit, toxicity (including quality of life), and other outcomes; (5) Assess the value of radiation therapy; and (6) Develop a radiation oncology registry. Conclusions: To our knowledge, this prioritization exercise is the only comprehensive and methodologically rigorous assessment of research needs in the field of radiation oncology. Broad dissemination of these findings is critical to maximally leverage the impact of this work, particularly because grant funding decisions are often made by committees on which highly specialized disciplines such as radiation oncology are not well represented.

Non-grey benchmark results for two temperature non-equilibrium radiative transfer

International Nuclear Information System (INIS)

Su, B.; Olson, G.L.

1999-01-01

Benchmark solutions to time-dependent radiative transfer problems involving non-equilibrium coupling to the material temperature field are crucial for validating time-dependent radiation transport codes. Previous efforts on generating analytical solutions to non-equilibrium radiative transfer problems were all restricted to the one-group grey model. In this paper, a non-grey model, namely the picket-fence model, is considered for a two temperature non-equilibrium radiative transfer problem in an infinite medium. The analytical solutions, as functions of space and time, are constructed in the form of infinite integrals for both the diffusion description and transport description. These expressions are evaluated numerically and the benchmark results are generated. The asymptotic solutions for large and small times are also derived in terms of elementary functions and are compared with the exact results. Comparisons are given between the transport and diffusion solutions and between the grey and non-grey solutions. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Radiation myelopathy

Energy Technology Data Exchange (ETDEWEB)

Howell, D A [Derbyshire Royal Infirmary, Derby (UK)

1979-10-01

Following high-dose radiotherapy treatment of tumours, there is a risk of destructive radiation myelopathy developing a few months later as a result of spinal cord irradiation. The emphasis of the present article is on the mechanism of the development of radiation myelopathy. It is suggested that, in the irradiated segments, the normal endothelial cells lining the penetrating arteries and capillaries are replaced by abnormal cells during the latent period. Radiation-induced mutations or chromosomal aberrations are contained in these cells, thus provoking an immunological response. During the attempted rejection of these cells, protein-rich plasma filtrate is leaked into the artery walls and nervous tissue, causing the destructive myelopathy. The signs of paralysis of spinal cord function may be caused either by infarcts or by oedema of the white matter. Since both diagnosis and treatment are difficult, it is necessary to concentrate on prevention by, whenever possible, reducing radiation doses to below tolerance limits during radiotherapy. As regards radiotherapy in children, it is currently believed that there is little or no difference in radiation tolerance between the child and the adult nervous system. Some early benign forms of radiation myelopathy are also briefly discussed.

Radiation myelopathy

International Nuclear Information System (INIS)

Howell, D.A.

1979-01-01

Following high-dose radiotherapy treatment of tumours, there is a risk of destructive radiation myelopathy developing a few months later as a result of spinal cord irradiation. The emphasis of the present article is on the mechanism of the development of radiation myelopathy. It is suggested that, in the irradiated segments, the normal endothelial cells lining the penetrating arteries and capillaries are replaced by abnormal cells during the latent period. Radiation-induced mutations or chromosomal aberrations are contained in these cells, thus provoking an immunological response. During the attempted rejection of these cells, protein-rich plasma filtrate is leaked into the artery walls and nervous tissue, causing the destructive myelopathy. The signs of paralysis of spinal cord function may be caused either by infarcts or by oedema of the white matter. Since both diagnosis and treatment are difficult, it is necessary to concentrate on prevention by, whenever possible, reducing radiation doses to below tolerance limits during radiotherapy. As regards radiotherapy in children, it is currently believed that there is little or no difference in radiation tolerance between the child and the adult nervous system. Some early benign forms of radiation myelopathy are also briefly discussed. (UK)

Genetical variability of Gladioli as the result of gamma-radiation

International Nuclear Information System (INIS)

Jakota, L.I.; Murin, A.V.

1994-01-01

In the starting material of Gladioli, got in the result of Y-radiation, the forms with white spots on the petals were observed. The Gladioli form 165-81 is distinguished by low growth and middle early flowering. The flower form is triangular. Basic pigmentation is red. White spots of different size on the petals were observed. The investigation was made in 1992 in the field of genetical variability of Gladioli. The Gladioli form 165-81 was irradiated with gamma-radiation dose 30 Gr. As a result the depression of biometric indicators was observed. Consequently, 30 Gr is a mutant dose for Gladioli

Coherent tunable far infrared radiation

Science.gov (United States)

Jennings, D. A.

1989-01-01

Tunable, CW, FIR radiation has been generated by nonlinear mixing of radiation from two CO2 lasers in a metal-insulator-metal (MIM) diode. The FIR difference-frequency power was radiated from the MIM diode antenna to a calibrated InSb bolometer. FIR power of 200 nW was generated by 250 mW from each of the CO2 lasers. Using the combination of lines from a waveguide CO2 laser, with its larger tuning range, with lines from CO2, N2O, and CO2-isotope lasers promises complete coverage of the entire FIR band with stepwise-tunable CW radiation.

Modelling of radiation impact on ITER Beryllium wall

Science.gov (United States)

Landman, I. S.; Janeschitz, G.

2009-04-01

In the ITER H-Mode confinement regime, edge localized instabilities (ELMs) will perturb the discharge. Plasma lost after each ELM moves along magnetic field lines and impacts on divertor armour, causing plasma contamination by back propagating eroded carbon or tungsten. These impurities produce enhanced radiation flux distributed mainly over the beryllium main chamber wall. The simulation of the complicated processes involved are subject of the integrated tokamak code TOKES that is currently under development. This work describes the new TOKES model for radiation transport through confined plasma. Equations for level populations of the multi-fluid plasma species and the propagation of different kinds of radiation (resonance, recombination and bremsstrahlung photons) are implemented. First simulation results without account of resonance lines are presented.

Modelling of radiation impact on ITER Beryllium wall

Energy Technology Data Exchange (ETDEWEB)

Landman, I.S. [Forschungszentrum Karlsruhe, IHM, FUSION, P.O. Box 3640, 76021 Karlsruhe (Germany)], E-mail: igor.landman@ihm.fzk.de; Janeschitz, G. [Forschungszentrum Karlsruhe, IHM, FUSION, P.O. Box 3640, 76021 Karlsruhe (Germany)

2009-04-30

In the ITER H-Mode confinement regime, edge localized instabilities (ELMs) will perturb the discharge. Plasma lost after each ELM moves along magnetic field lines and impacts on divertor armour, causing plasma contamination by back propagating eroded carbon or tungsten. These impurities produce enhanced radiation flux distributed mainly over the beryllium main chamber wall. The simulation of the complicated processes involved are subject of the integrated tokamak code TOKES that is currently under development. This work describes the new TOKES model for radiation transport through confined plasma. Equations for level populations of the multi-fluid plasma species and the propagation of different kinds of radiation (resonance, recombination and bremsstrahlung photons) are implemented. First simulation results without account of resonance lines are presented.

The inhibition of PARP but not EGFR results in the radiosensitization of HPV/p16-positive HNSCC cell lines

International Nuclear Information System (INIS)

Güster, Julian David; Weissleder, Stephanie Valerie; Busch, Chia-Jung; Kriegs, Malte; Petersen, Cordula; Knecht, Rainald; Dikomey, Ekkehard; Rieckmann, Thorsten

2014-01-01

Background and purpose: HPV-negative and HPV-positive HNSCC comprise distinct tumor entities with different biological characteristics. Specific regimens for the comparably well curable HPV-positive entity that reduce side effects without compromising outcome have yet to be established. Therefore, we tested here whether the inhibition of EGFR or PARP may be used to specifically enhance the radiosensitivity of HPV-positive HNSCC cells. Materials and methods: Experiments were performed with five HPV/p16-positive HNSCC cell lines. Inhibitors used were cetuximab, olaparib and PF-00477736. The respective inhibition of EGFR, PARP and Chk1 was evaluated by Western blot, immunofluorescence analysis and assessment of cell cycle distribution. Cell survival was assessed by colony formation assay. Results: Inhibition of EGFR by cetuximab failed to radiosensitize any of the HPV-positive HNSCC cell lines tested. In contrast, PARP-inhibition resulted in a substantial radiosensitization of all strains, with the sensitization being further enhanced by the additional inhibition of Chk1. Conclusions: PARP-inhibition effectively radiosensitizes HPV-positive HNSCC cells and may therefore represent a viable alternative to chemotherapy possibly even allowing for a reduction in radiation dose. For the latter, PARP-inhibition may be combined with the inhibition of Chk1. In contrast, the inhibition of EGFR cannot be expected to radiosensitize HPV-positive HNSCC through the modulation of cellular radiosensitivity

Collision and radiative processes in emission of atmospheric carbon dioxide

Science.gov (United States)

Smirnov, B. M.

2018-05-01

The peculiarities of the spectroscopic properties of CO2 molecules in air due to vibration-rotation radiative transitions are analyzed. The absorption coefficient due to atmospheric carbon dioxide and other atmospheric components is constructed within the framework of the standard atmosphere model, on the basis of classical molecular spectroscopy and the regular model for the spectroscopy absorption band. The radiative flux from the atmosphere toward the Earth is represented as that of a blackbody, and the radiative temperature for emission at a given frequency is determined with accounting for the local thermodynamic equilibrium, a small gradient of the tropospheric temperature and a high optical thickness of the troposphere for infrared radiation. The absorption band model with an absorption coefficient averaged over the frequency and line-by-line model are used for evaluating the radiative flux from the atmosphere to the Earth which values are nearby for these models and are equal W m‑2 for the contemporary concentration of atmospheric CO2 molecules and W m‑2 at its doubled value. The absorption band model is not suitable to calculate the radiative flux change at doubling of carbon dioxide concentration because averaging over oscillations decreases the range where the atmospheric optical thickness is of the order of one, and just this range determines this change. The line-by-line method gives the change of the global temperature K as a result of doubling the carbon dioxide concentration. The contribution to the global temperature change due to anthropogenic injection of carbon dioxide in the atmosphere, i.e. resulted from combustion of fossil fuels, is approximately 0.02 K now.

Luminescence in Primordial Helium Lines at the Pre-recombination Epoch

Science.gov (United States)

Dubrovich, V. K.; Grachev, S. I.

2018-04-01

The formation of luminescent subordinate He I lines by the absorption of radiation from a source in lines of the main He I series in an expanding Universe is considered. A burst of radiation in continuum is assumed to occur at some instant of time corresponding to redshift z 0. This radiation is partially absorbed at different z < z 0 in lines of the main He I series (different pumping channels) and then is partially converted into radiation in subordinate lines. If ν ik is the laboratory transition frequency of some subordinate line emerging at some z, then at the present epoch its frequency will be ν = ν ik /(1 + z). The quantum yield, i.e., the number of photons emitted in the subordinate line per initial excited atom, has been calculated for different z (and, consequently, for different ν). Several pumping channels have been considered. We show that the luminescent lines can be both emission and absorption ones; the same line can be an emission one for one of the pumping channels and an absorption one for another. For example, the 1s2s-1s2p (1S-1P*) line is an emission one for the 1s2-1s2p pumping and an absorption one for the 1s2-1s3p pumping. We show that in the frequency range 30-80 GHz the total quantum yield for the first and second of the above channels can reach +50 and -50%, respectively.

Definitions, qualifications and requirements for radiation protection experts, radiation protection officers and radiation workers: results of the 2 nd EUTERP Workshop

International Nuclear Information System (INIS)

Draaisma, Folkert S.; Steen, Jan van der

2008-01-01

Full text: In Europe, a common vision for maintaining competence in radiation protection is emerging, focussing on a common denominator for qualification of radiation protection experts (RPEs) and radiation protection officers (RPOs) and for mutual recognition and mobility of these professionals across the European Union. Therefore, the European Commission, D.-G. Transport and Energy, has launched an initiative to establish a European Radiation Protection Training and Education Platform (EUTERP Platform). The objectives of the Platform can be summarised as: to facilitate the trans national access to vocational education and training; to better integrate education and training into occupational radiation protection infrastructures in the Member, Candidate and Associated States of the European Union. The Platform ensures a permanent dialogue between all involved parties by the use of its web site (www.euterp.eu), by issuing newsletters and by organising workshops. The first workshop has been held in Vilnius, 22-24 May 2007, and resulted in 8 recommendations to the European Commission, the IAEA, IRPA and national authorities. The recommendations were, a.o., dealing with: new definitions for the Radiation Protection Expert (RPE) and the Radiation Protection Officer (RPO), which should be used in the revision of both the EURATOM and the International BSS; developing guidance for a methodology to compare the quality of training courses and training material; developing guidance for a standardized methodology of assessing the recognition of RP professionals as a basis for future mutual recognition, based on a description of roles and duties, education, training and work experience; developing guidance for a formal recognition process of the competence of RPEs and RPOs. The second workshop will be held on 23-25 April 2008, again in Vilnius, and will specifically discuss the above-mentioned proposals for new definitions and guidance material. It is expected that the

[Influence of low doses of ionizing radiation on tenascin expression in hybridoma cell systems].

Science.gov (United States)

Lunga, I N

2003-01-01

One of the achievements of the modern radiation ecology is the preparation and application of stable eukariotic cell lines to solve various problems occurring under exposure to ionizing radiation, especially to low doses. The detection of onco-fetal protein--tenascin in different embryonic and tumor cells of humans and animals supposes the probability of appropriate gene expression in lymphoid cells, including hybridomal cells. Using the immunochemical method, the study of tenascin expression in two mouse hybridomal lines was carried out. Tenascin was revealed in hybridomal lines MLC-1 and K-48. Further hybridomal cell lines were exposed to X-ray radiation (120 KV) with doses 2.10,15 cGy. The obtained results demonstrated the sensitivity of tenascin expression to low doses of ionizing radiation, that may be used as a convenient model of studying of genotoxic effects of various damaging ionizing agents on a cell level.

Lung Cancer Cell Line Screen Links Fanconi Anemia/BRCA Pathway Defects to Increased Relative Biological Effectiveness of Proton Radiation

International Nuclear Information System (INIS)

Liu, Qi; Ghosh, Priyanjali; Magpayo, Nicole; Testa, Mauro; Tang, Shikui; Gheorghiu, Liliana; Biggs, Peter; Paganetti, Harald; Efstathiou, Jason A.; Lu, Hsiao-Ming; Held, Kathryn D.; Willers, Henning

2015-01-01

Purpose: Growing knowledge of genomic heterogeneity in cancer, especially when it results in altered DNA damage responses, requires re-examination of the generic relative biological effectiveness (RBE) of 1.1 of protons. Methods and Materials: For determination of cellular radiosensitivity, we irradiated 17 lung cancer cell lines at the mid-spread-out Bragg peak of a clinical proton beam (linear energy transfer, 2.5 keV/μm). For comparison, 250-kVp X rays and 137 Cs γ-rays were used. To estimate the RBE of protons relative to 60 Co (Co60eq), we assigned an RBE(Co60Eq) of 1.1 to X rays to correct the physical dose measured. Standard DNA repair foci assays were used to monitor damage responses. FANCD2 was depleted using RNA interference. Results: Five lung cancer cell lines (29.4%) exhibited reduced clonogenic survival after proton irradiation compared with X-irradiation with the same physical doses. This was confirmed in a 3-dimensional sphere assay. Corresponding proton RBE(Co60Eq) estimates were statistically significantly different from 1.1 (P≤.05): 1.31 to 1.77 (for a survival fraction of 0.5). In 3 of these lines, increased RBE was correlated with alterations in the Fanconi anemia (FA)/BRCA pathway of DNA repair. In Calu-6 cells, the data pointed toward an FA pathway defect, leading to a previously unreported persistence of proton-induced RAD51 foci. The FA/BRCA-defective cells displayed a 25% increase in the size of subnuclear 53BP1 foci 18 hours after proton irradiation. Conclusions: Our cell line screen has revealed variations in proton RBE that are partly due to FA/BRCA pathway defects, suggesting that the use of a generic RBE for cancers should be revisited. We propose that functional biomarkers, such as size of residual 53BP1 foci, may be used to identify cancers with increased sensitivity to proton radiation

Lung Cancer Cell Line Screen Links Fanconi Anemia/BRCA Pathway Defects to Increased Relative Biological Effectiveness of Proton Radiation

Energy Technology Data Exchange (ETDEWEB)

Liu, Qi; Ghosh, Priyanjali; Magpayo, Nicole [Laboratory of Cellular and Molecular Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Testa, Mauro; Tang, Shikui [Division of Radiation Physics, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Gheorghiu, Liliana [Laboratory of Cellular and Molecular Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Biggs, Peter; Paganetti, Harald [Division of Radiation Physics, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Efstathiou, Jason A. [Laboratory of Cellular and Molecular Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Lu, Hsiao-Ming [Division of Radiation Physics, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Held, Kathryn D. [Laboratory of Cellular and Molecular Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Willers, Henning, E-mail: hwillers@mgh.harvard.edu [Laboratory of Cellular and Molecular Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)

2015-04-01

Purpose: Growing knowledge of genomic heterogeneity in cancer, especially when it results in altered DNA damage responses, requires re-examination of the generic relative biological effectiveness (RBE) of 1.1 of protons. Methods and Materials: For determination of cellular radiosensitivity, we irradiated 17 lung cancer cell lines at the mid-spread-out Bragg peak of a clinical proton beam (linear energy transfer, 2.5 keV/μm). For comparison, 250-kVp X rays and {sup 137}Cs γ-rays were used. To estimate the RBE of protons relative to {sup 60}Co (Co60eq), we assigned an RBE(Co60Eq) of 1.1 to X rays to correct the physical dose measured. Standard DNA repair foci assays were used to monitor damage responses. FANCD2 was depleted using RNA interference. Results: Five lung cancer cell lines (29.4%) exhibited reduced clonogenic survival after proton irradiation compared with X-irradiation with the same physical doses. This was confirmed in a 3-dimensional sphere assay. Corresponding proton RBE(Co60Eq) estimates were statistically significantly different from 1.1 (P≤.05): 1.31 to 1.77 (for a survival fraction of 0.5). In 3 of these lines, increased RBE was correlated with alterations in the Fanconi anemia (FA)/BRCA pathway of DNA repair. In Calu-6 cells, the data pointed toward an FA pathway defect, leading to a previously unreported persistence of proton-induced RAD51 foci. The FA/BRCA-defective cells displayed a 25% increase in the size of subnuclear 53BP1 foci 18 hours after proton irradiation. Conclusions: Our cell line screen has revealed variations in proton RBE that are partly due to FA/BRCA pathway defects, suggesting that the use of a generic RBE for cancers should be revisited. We propose that functional biomarkers, such as size of residual 53BP1 foci, may be used to identify cancers with increased sensitivity to proton radiation.

Radiosensitive Down syndrome lymphoblastoid lines have normal ionizing-radiation-induced inhibition of DNA synthesis

International Nuclear Information System (INIS)

Ganges, M.B.; Robbins, J.H.; Jiang, H.; Hauser, C.; Tarone, R.E.

1988-01-01

The extent of X-ray-induced inhibition of DNA synthesis was determined in radiosensitive lymphoblastoid lines from 3 patients with Down syndrome and 3 patients with ataxia telangiectasia (AT). Compared to 6 normal control lines, the 3 AT lines were abnormally resistant to X-ray-induced inhibition of DNA synthesis, while the 3 Down syndrome lines had normal inhibition. These results demonstrate that radiosensitive human cells can have normal X-ray-induced inhibition of DNA synthesis and provide new evidence for the dissociation of radioresistant DNA synthesis. (author). 27 refs.; 1 fig.; 1 tab

The elettra beam line control system

International Nuclear Information System (INIS)

Mignacco, M.; Abrami, A.; Dequal, Z.

1994-01-01

Elettra is a third generation Synchrotron Light Source located in Trieste (Italy). It consists of a full energy linac injector and a storage ring with beam energies between 1.5 and 2 GeV. The facility is scheduled to be operational by end 1993. For the whole project 22 beam lines from insertion devices are foreseen, each of them is composed of a large number of measurement and controls instruments, most of them embedded in intelligent devices; in addition each beam line can be considered unique compared to the others, having been designed to provide a different kind of synchrotron radiation. This results in a large not homogenous environment where more than 200,000 physical points have to be controlled. A joint team composed of Softeco Sismat and Digital Equipment has developed a fully automated beam line control system able to give full remote controls, with different kind of access rights, to beam line users and beam line specialists as well as a full integration with experiment control systems. ((orig.))

Radiation protection research and training programme review radiation protection programme 1960-89 synopsis of results 1985-89

International Nuclear Information System (INIS)

1990-01-01

This document aims to trace the evolution of the CEC radiation protection programme over its 30 years of existence. During this time, research carried out in the framework of the Community programme has made major contributions to the scientific understanding of the action of ionizing radiation and the protection of man and his environment. This information was crucial for developing better radiation protection management for existing and new technologies and for providing the scientific basis for the regulatory activities of the Commission. One important feature of the programme was the success of bringing together scientists from different Member States to cooperate in the various fields of radiation protection and to integrate different areas of radiation protection research into a coherent approach. The structures thus developed within the programme have enabled research in radiation protection to be conducted in a cost-effective manner on behalf of the Member States. This document aims also to give a synopsis of the most important results of the 1985-89 radiation protection programme. This period was characterized by two challenges, the integration of two Member States into Community research and the impact of the Chernobyl accident. The programme has, in spite of reduced funding, continued to provide a high degree of expertise for the Community in the context of the needs in radiation protection. This has been explicity acknowledged in the evaluation of the 1980-89 programmes carried out by an independent panel

Proposed dedicated high pressure beam lines at CHESS

International Nuclear Information System (INIS)

Ruoff, A.L.; Vohra, Y.K.; Bassett, W.A.; Batterman, B.W.; Bilderback, D.H.

1988-01-01

An instrumentation proposal for dedicated high pressure beam lines at CHESS is described. It is the purpose of this proposed program to provide researchers in high pressure science with beam lines for X-ray diffraction studies in the megabar regime. This will involve radiation from a bending magnet as well as from a wiggler. Examples of the high pressure results up to 2.16 Mbar are shown. Diffraction patterns from bending magnet and wiggler beams are shown and compared. The need for this facility by the high pressure community is discussed. (orig.)

Some Results On The Modelling Of TSS Manufacturing Lines

Directory of Open Access Journals (Sweden)

Viorel MÎNZU

2000-12-01

Full Text Available This paper deals with the modelling of a particular class of manufacturing lines, governed by a decentralised control strategy so that they balance themselves. Such lines are known as “bucket brigades” and also as “TSS lines”, after their first implementation, at Toyota, in the 70’s. A first study of their behaviour was based upon modelling as stochastic dynamic systems, which emphasised, in the frame of the so-called “Normative Model”, a sufficient condition for self-balancing, that means for autonomous functioning at a steady production rate (stationary behaviour. Under some particular conditions, a simulation analysis of TSS lines could be made on non-linear block diagrams, showing that the state trajectories are piecewise continuous in between occurrences of certain discrete events, which determine their discontinuity. TSS lines may therefore be modelled as hybrid dynamic systems, more specific, with autonomous switching and autonomous impulses (jumps. A stability analysis of such manufacturing lines is allowed by modelling them as hybrid dynamic systems with discontinuous motions.

Stacked dipole line source excitation of active nano-particles

DEFF Research Database (Denmark)

Arslanagic, Samel

This work investigates electromagnetic properties of cylindrical active coated nano-particles excited by a stac- ked electric dipole line source. The nano-particles consist of a silica nano-core, layered by silver, gold, or copper nano-shell. Attention is devoted to the influence of the source...... location and dipole orientation, the gain constant, and the nano-particle material composition on the electromagnetic field distributions and radiated powers. The results are contrasted to those for the magnetic line source illumination of the nano-particles....

Enhancement of Radiation Effects by Ursolic Acid in BGC-823 Human Adenocarcinoma Gastric Cancer Cell Line.

Directory of Open Access Journals (Sweden)

Yang Yang

Full Text Available Recent research has suggested that certain plant-derived polyphenols, i.e., ursolic acid (UA, which are reported to have antitumor activities, might be used to sensitize tumor cells to radiation therapy by inhibiting pathways leading to radiation therapy resistance. This experiment was designed to investigate the effects and possible mechanism of radiosensitization by UA in BGC-823 cell line from human adenocarcinoma gastric cancer in vitro. UA caused cytotoxicity in a dose-dependent manner, and we used a sub-cytotoxicity concentration of UA to test radioenhancement efficacy with UA in gastric cancer. Radiosensitivity was determined by clonogenic survival assay. Surviving fraction of the combined group with irradiation and sub-cytotoxicity UA significantly decreased compared with the irradiation group. The improved radiosensitization efficacy was associated with enhanced G2/M arrest, increased reactive oxygen species (ROS, down-regulated Ki-67 level and improved apoptosis. In conclusion, as UA demonstrated potent antiproliferation effect and synergistic effect, it could be used as a potential drug sensitizer for the application of radiotherapy.

The origin of coronal lines in Seyfert galaxies

International Nuclear Information System (INIS)

Korista, K.T.; Ferland, G.J.

1989-01-01

This paper examines the possibility that the coronal line region in Seyfert galaxies may be the result of an interstellar medium (ISM) exposed to, and subsequently photoionized by, a 'bare' Seyfert nucleus. It is shown that a 'generic' AGN continuum illuminating the warm-phase of the ISM of a spiral galaxy can produce the observed emission. In this picture the same UV-radiation cone that is responsible for the high-excitation extended narrow-line emission clouds observed out to 1-2 kpc or farther from the nuclei of some Seyfert galaxies also produces the coronal lines. Soft X-rays originating in the nucleus are Compton-scattered off the ISM, thus producing extended soft X-ray emission, as observed in NGC 4151. The results of the calculations show a basic insensitivity to the ISM density, which explains why similar coronal line spectra are found in many Seyfert galaxies of varying physical environments. 60 refs

Harmonics radiation of graphene surface plasmon polaritons in terahertz regime

Energy Technology Data Exchange (ETDEWEB)

Li, D., E-mail: dazhi_li@hotmail.com [Institute for Laser Technology, Suita, Osaka 565-0871 (Japan); Wang, Y. [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China); Nakajima, M. [Institute of Laser Engineering, Osaka University, Suita, Osaka 565-0871 (Japan); Hashida, M. [Advanced Research Center for Beam Science, ICR, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Wei, Y. [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China); Miyamoto, S. [Laboratory of Advanced Science and Technology for Industry, University of Hyogo, Ako, Hyogo 678-1205 (Japan)

2016-06-03

This letter presents an approach to extract terahertz radiation from surface plasmon polaritons excited in the surface of a uniform graphene structure by an electron beam. A sidewall configuration is proposed to lift the surface plasmon mode to be close to the light line, so that some of its harmonics have chances to go above the light line and become radiative. The harmonics are considered to be excited by a train of periodic electron bunches. The physical mechanism in this scheme is analyzed with three-dimensional theory, and the harmonics excitation and radiation are demonstrated through numerical calculations. The results show that this technique could be an alternative to transform the surface plasmon polaritons into radiation. - Highlights: • An approach to extract terahertz radiation from graphene surface plasmon polaritons is presented. • A sidewall configuration is proposed to lift the surface plasmon mode. • Harmonics of surface plasmon polaritons are possible to radiate.

Opacity of expanding media: The effect of spectral lines

International Nuclear Information System (INIS)

Karp, A.H.; Lasher, G.; Chan, K.L.; Salpeter, E.E.

1977-01-01

Spectral lines are more effective in slowing the transport of radiation in expanding (or contracting) objects than in static ones. The velocity gradient associated with the expansion causes the frequency of the photons to be continuously redshifted relative to the rest frame of the gas through which they travel. Those photons which are redshifted to the frequency of a sufficiently strong line will be absorbed by the corresponding bound-bound transition, and the net effect will be to increase the effective opacity of the gas. In certain cases the effect can be taken into account by using an effective opacity, the expansion opacity, which is a function not only of the temperature and density but also of the velocity gradient.Practical formulae for computing the expansion opacity and its Rosseland mean in terms of sums over spectral lines are derived. It is shown that the cumulative effect of many weak lines can be important, implying that a large list of spectral lines is required to obtain results of even modest accuracy. Numerical computations using the 260,000-entry line list of Kurucz and Peytremann have been completed and some samples of the result are given. The general effect may be important in many astronomical objects, but only in some of these will be detailed approach of this paper be appropriate. In optically thick supernova shells, the effect is important both in maintaining the radiation in thermal equilibrium as it diffuses out of the shell and in increasing the value of the total opacity. The enhancement of the opacity ranges from less than 1% to more than an order of magnitude, depending on the temperature, density, and velocity gradient

Beam line design using G4BeamLine

CERN Document Server

Dogan, Arda

2014-01-01

In Turkey in Ankara TAEK SANAEM Proton Accelerator Facility (PAF), there is a cyclotron which produces a focused intense 30 MeV proton beam and sends this beam to four different arms, three of which uses this beam to produce pharmaceutical medicine. The remaining one is spared for R&D purposes and the idea was to use these protons coming out from the fourth arm to use space radiation tests, which cannot be done in Turkey at the moment. However, according to SCC 25100 standards which is for 30 MeV protons, the beam coming out of cyclotron is too intense and focused to use for space radiation tests. Therefore, the main aim of my project is to design a beam line which will defocus the beam and reduce the flux so that the space radiation tests can be done according to the standards of SCC 25100.

Inversion of the OH 1720-MHz line

International Nuclear Information System (INIS)

Elitzur, M.

1975-01-01

It is shown that the OH 1720-MHz line can be strongly inverted by collisions which excite the rotation states. It is also argued that radiative pumps (of any wave length) can invert strongly only the 1612-MHz line. (author)

Spectrophotometry of Bowen resonance fluorescence lines in three planetary nebulae

Science.gov (United States)

O'Dell, C. R.; Miller, Christopher O.

1992-01-01

The results are presented of a uniquely complete, carefully reduced set of observations of the O III Bowen fluorescence lines in the planetary nebulae NGC 6210, NGC 7027, and NGC 7662. A detailed comparison with the predictions of radiative excitation verify that some secondary lines are enhanced by selective population by the charge exchange mechanism involving O IV. Charge exchange is most important in NGC 6210, which is of significantly lower ionization than the other nebulae. In addition to the principal Bowen lines arising from Ly-alpha pumping of the O III O1 line, lines arising from pumping of the O3 line are also observed. Comparison of lines produced by O1 and O3 with the theoretical predictions of Neufeld indicate poor agreement; comparison with the theoretical predictions of Harrington show agreement with NGC 7027 and NGC 7662.

Characterization of the Goubau line for testing beam diagnostic instruments

Science.gov (United States)

Kim, S. Y.; Stulle, F.; Sung, C. K.; Yoo, K. H.; Seok, J.; Moon, K. J.; Choi, C. U.; Chung, Y.; Kim, G.; Woo, H. J.; Kwon, J.; Lee, I. G.; Choi, E. M.; Chung, M.

2017-12-01

One of the main characteristics of the Goubau line is that it supports a low-loss, non-radiated surface wave guided by a dielectric-coated metal wire. The dominant mode of the surface wave along the Goubau line is a TM01 mode, which resembles the pattern of the electromagnetic fields induced in the metallic beam pipe when the charged particle beam passes through it. Therefore, the Goubau line can be used for the preliminary bench test and performance optimization of the beam diagnostic instruments without requiring charged particle beams from the accelerators. In this paper, we discuss the basic properties of the Goubau line for testing beam diagnostic instruments and present the initial test results for button-type beam position monitors (BPMs). The experimental results are consistent with the theoretical estimations, which indicates that Goubau line allows effective testing of beam diagnostic equipment.

Experimental results of the ATF in-line injection system

International Nuclear Information System (INIS)

Wang, X.J.; Srinivasan-Rao, T.; Batchelor, K.

1995-01-01

The initial experimental results of the Brookhaven accelerator test facility (ATF) in-line injector is presented. The ATF in-line injector employed a full copper RF gun with a pair of solenoid magnets for emittance compensation. The maximum acceleration field of the RF gun was measured to be 130 MV/m. The electron yield from the copper cathode was maximized using p- polarized laser and the Schottky effect. The quantum efficiency under optimum conditions was measured to be 0.04%. The measured electron bunch length was less than 11 ps, which agreed with the laser pulse length measurement using a streak camera. The normalized rms. emittance for 0.25 nC charge is 0.9 ± 0.1 mm-mrad, which is almost four times smaller than the emittance predicted by the space-charge effect for a non-emittance compensation photocathode RF gun. The normalized rms for 0.6 nC charge was measured range from 1 to 3 mm-mrad. This measurement was first experimental demonstration of emittance compensation in a high-gradient, S-band photocathode RF gun

Intra lines uniformity and inter lines variation of rice mutants resulting from irradiation of South Kalimantan local varieties

International Nuclear Information System (INIS)

Raihani Wahdah; Gusti Rumayadi; Rahmi Zulhidiani

2016-01-01

The preference of farmer in tidal swamp on local rice varieties are quite high, but local varieties have a long life and low yield characters, so it needs to be improved for the trait. This study is part of activities of the local rice varieties improvement to generate promising lines were short-moderate aged, but the slimming and pera (high amylose content) grains maintained. The aims of this study were to determine the intra lines uniformity and the inter lines variation of M5 generation of rice mutant lines. The experiment was carried out in the Experimental Station of Agriculture Faculty, Lambung Mangkurat University from March to September 2014. The experiment used 150 earliest flowering lines of 300 M5 mutant lines that were planted. Intra lines uniformity were analysed by comparing the variance of each mutant lines with variance of its parent, while the variation among lines were analyzed by comparing the variance of all lines with variance of its parent. More than 85 % M5 mutant lines from Siam Harli as parent and > 79 % of Siam Kuatek as parent are uniform. The uniform character at all M5 mutant lines, both of Siam Harli or Siam Kuatek parent are the harvest age, the filled grains number, and the empty grains number. There is no variability between M5 mutant lines, but some of M5 mutant lines from Siam Harli and Siam Kuatek have some better characters than their parents, so there is an opportunity for selection. (author)

Identification of radiation-induced hydrocarbons in halibut, cod and prawns by on-line coupled LC-GC/MS technique

International Nuclear Information System (INIS)

Spiegelberg, A.; Schulzki, G.; Boegl, K.W.; Schreiber, G.A.

1997-01-01

Radiation-induced hydrocarbons were analysed in a fatty (halibut) and a lean fish (cod) as well as in a prawn species by on-line coupled liquid chromatography (LC) - gas chromatography (GC) combined with mass spectrometrical detection. In irradiated halibut which contains mainly saturated and monounsaturated fatty acids all expected radiolytic alkanes, alkenes and alkadienes could be detected. The yields of the C n-1 and C n-2:1 hydrocarbons were comparable with those found in irradiated lipids of land animals and plants. However, in cod and the prawn species which contain high levels of polyunsaturated fatty acids (PUFA), the C n-1 hydrocarbons were found in concentrations up to tenfold higher whereas the C n-2:1 products were again comparable to those of land animals and plants. The identification of radiation-induced hydrocarbons in fish lipids was achieved by transfer of the hydrocarbons from the LC column to the gas chromatographic column in fractions differing in the degree of unsaturation. For the first time radiation induced hydrocarbons with more than four double bonds generated from polyunsaturated fatty acids (20:4ω6 and 20:5ω3) could be identified. (orig.) [de

Assessment of genetic results of ionizing radiation effect on hydrobionts population

International Nuclear Information System (INIS)

Pechkurenkov, V.L.; Pokrovskaya, L.G.; Fetisov, A.N.

1987-01-01

The effect of dose value and rate on genetic results of chronic radiation with the low dose rate is estimated. At such irradiation the yield of abberant anaphases of embryos is determined by the dose value and it does not depend on the dose rate. The threshold radiation dose rate of the developing fish roe equals 2-3 cGy/h when ignoring the medium modifying factors. The estimation of possible limits of modification of genetic effects of radiation with the low rate when changing environmental factors is given. The model allowing to forecast the appearance of genetic effects of radiation with the low dose rate is constructed. The correspondence between the data obtained in laboratory experiments using organisms living in water reservoirs contaminated experimentally by radionuclides is marked

On-line monitoring system for I-131 manufacturing labs

International Nuclear Information System (INIS)

Osovizky, A.; Malamud, Y.; Paran, Y.; Tal, N.; Turgeman, S.; Weinstein, M.

1997-01-01

An on-line monitoring and safety system has been installed in a lab for manufacturing 1-131 capsules for nuclear medicine use. Production of up to 100mCi batches is performed in shielded glove boxes. The safety system is based on a unique, 'Medi SMARTS' system (Medical Survey Mapping Automatic Radiation Tracing System), that collects continuously the radiation measurements for processing, display, and storage for future retrieval. Radiation is measured by GM tubes, data is transferred to a data processing unit, and then via a RS-485 communication line to a computer. In addition to the operational advantages and radiation levels storage, the system is being evaluated for the purpose of identifying risky stages in the process. (authors)

Observations of 50/60 Hz Power Line Radiation in the Low Latitude Ionosphere Detected by the Electric Field Instrument on the C/NOFS Satellite

Science.gov (United States)

Pfaff, R. F., Jr.; Freudenreich, H. T.; Simoes, F. A.; Liebrecht, M. C.; Farrell, W.

2017-12-01

One of the most ubiquitous forms of EM radiation emanating from the earth's surface is that of power line radiation. Associated with AC electric power generation, such emissions are typically launched along conducting power lines that may travel hundreds, or even thousands of km, from generating stations. The fundamental frequencies of such emissions are characteristically 50 Hz or 60 Hz, depending on the regional standards for power generation/consumption. The frequency of this radiation is well below that of the plasma frequency of the ionosphere (typically several MHz) and hence is expected to reflect back to the earth and propagate in the waveguide formed by the earth's surface and the bottom ledge of the ionosphere, typically near 100 km. Given that such power lines are widespread on the exposed lithosphere, the leakage of some ELF emissions associated with electric power generation might nevertheless be expected in the ionosphere, in the same manner in which a small fraction of the power associated with ELF Schumann resonances and lightning sferics have been shown to penetrate into the ionosphere. We present direct measurements of 50/60 Hz power line radiation detected by in situ probes on an orbiting satellite in the earth's ionosphere. The data were gathered by the Vector Electric Field Investigation (VEFI) tri-axial double probe detector flown on the Communication/Navigation Outage Forecast System (C/NOFS) satellite. C/NOFS was launched in April, 2008 into a low latitude (13 deg inclination) orbit with perigee and apogee of 400 km and 850 km, respectively. The electric field wave data were gathered by ELF receivers comprised of two orthogonal broadband channels sampled at 512 s/sec each, and digitized with 16 bit A/D converters. The data show distinct 60 Hz emissions while the satellite sampled within the Brazilian sector whereas distinct 50 Hz emissions were detected over India. Other, less distinct, emissions were observed over Africa and southeast Asia

Mobile phone radiation induces mode-dependent DNA damage in a mouse spermatocyte-derived cell line: a protective role of melatonin.

Science.gov (United States)

Liu, Chuan; Gao, Peng; Xu, Shang-Cheng; Wang, Yuan; Chen, Chun-Hai; He, Min-Di; Yu, Zheng-Ping; Zhang, Lei; Zhou, Zhou

2013-11-01

To evaluate whether exposure to mobile phone radiation (MPR) can induce DNA damage in male germ cells. A mouse spermatocyte-derived GC-2 cell line was exposed to a commercial mobile phone handset once every 20 min in standby, listen, dialed or dialing modes for 24 h. DNA damage was determined using an alkaline comet assay. The levels of DNA damage were significantly increased following exposure to MPR in the listen, dialed and dialing modes. Moreover, there were significantly higher increases in the dialed and dialing modes than in the listen mode. Interestingly, these results were consistent with the radiation intensities of these modes. However, the DNA damage effects of MPR in the dialing mode were efficiently attenuated by melatonin pretreatment. These results regarding mode-dependent DNA damage have important implications for the safety of inappropriate mobile phone use by males of reproductive age and also suggest a simple preventive measure: Keeping mobile phones as far away from our body as possible, not only during conversations but during 'dialed' and 'dialing' operation modes. Since the 'dialed' mode is actually part of the standby mode, mobile phones should be kept at a safe distance from our body even during standby operation. Furthermore, the protective role of melatonin suggests that it may be a promising pharmacological candidate for preventing mobile phone use-related reproductive impairments.

Results of Radiation Therapy in Stage III Uterine Cervical Cancer

Energy Technology Data Exchange (ETDEWEB)

Moon, Chang Woo; Shin, Byung Chul; Yum, Ha Yong; Jeung, Tae Sig; Yoo, Myung Jin [Kosin University College of Medicine, Seoul (Korea, Republic of)

1995-09-15

Purpose : The aim of this study is to analyze the survival rate, treatment failure and complication of radiation therapy alone in stage III uterine cervical cancer. Materials and Methods : From January 1980 through December 1985, 227 patients with stage II uterine cervical cancer treated with radiation therapy at Kosin Medical Center were retrospectively studied. Among 227 patients, 72 patients(31.7%) were stage IIIa, and 155 patients(68.3%) were stage IIIb according to FIGO classification. Age distribution was 32-71 years(median: 62 years). Sixty nine patients(95.8%) in stage IIIa and 150 patients(96.8%) in stage IIIb were squamous cell carcinoma. Pelvic lymph node metastasis at initial diagnosis was 8 patients (11.1%) in stage IIIa and 29 patients(18.7%) in stage IIIb. Among 72 patients with stage IIIa, 36 patients(50%) were treated with external radiation therapy alone by conventional technique (180-200 cGy/fr). And 36 patients(50%) were treated with external radiation therapy with intracavitary radiotherapy(ICR) with Cs137 sources, and among 155 patients with stage IIIb, 80 patients(51.6%) were treated with external radiation therapy alone and 75 patients(48.4%) were treated with external radiation therapy with ICR. Total radiation doses of stage IIIa and IIIb were 65-105 Gy(median : 78.5 Gy) and 65-125.5 Gy (median :83.5 Gy). Survival rate was calculated by life-table method. Results : Complete response rates were 58.3% (42 patients) in state IIIa and 56.1%(87 patients) in stage Iiib. Overall 5 year survival rates were 57% in stage IIIa and 40% in stage IIIb. Five year survival rates by radiation technique in stage IIIa and IIIb were 64%, 40% in group treated in combination of external radiation and ICR, and 50%, 40% in the group of external radiation therapy alone(P=NS). Five year survival rates by response of radiation therapy in stage IIIa and IIIb were 90%, 66% in responder group, and 10%, 7% in non-responder group (P<0.01). There were statistically no

Results of Radiation Therapy in Stage III Uterine Cervical Cancer

International Nuclear Information System (INIS)

Moon, Chang Woo; Shin, Byung Chul; Yum, Ha Yong; Jeung, Tae Sig; Yoo, Myung Jin

1995-01-01

Purpose : The aim of this study is to analyze the survival rate, treatment failure and complication of radiation therapy alone in stage III uterine cervical cancer. Materials and Methods : From January 1980 through December 1985, 227 patients with stage II uterine cervical cancer treated with radiation therapy at Kosin Medical Center were retrospectively studied. Among 227 patients, 72 patients(31.7%) were stage IIIa, and 155 patients(68.3%) were stage IIIb according to FIGO classification. Age distribution was 32-71 years(median: 62 years). Sixty nine patients(95.8%) in stage IIIa and 150 patients(96.8%) in stage IIIb were squamous cell carcinoma. Pelvic lymph node metastasis at initial diagnosis was 8 patients (11.1%) in stage IIIa and 29 patients(18.7%) in stage IIIb. Among 72 patients with stage IIIa, 36 patients(50%) were treated with external radiation therapy alone by conventional technique (180-200 cGy/fr). And 36 patients(50%) were treated with external radiation therapy with intracavitary radiotherapy(ICR) with Cs137 sources, and among 155 patients with stage IIIb, 80 patients(51.6%) were treated with external radiation therapy alone and 75 patients(48.4%) were treated with external radiation therapy with ICR. Total radiation doses of stage IIIa and IIIb were 65-105 Gy(median : 78.5 Gy) and 65-125.5 Gy (median :83.5 Gy). Survival rate was calculated by life-table method. Results : Complete response rates were 58.3% (42 patients) in state IIIa and 56.1%(87 patients) in stage Iiib. Overall 5 year survival rates were 57% in stage IIIa and 40% in stage IIIb. Five year survival rates by radiation technique in stage IIIa and IIIb were 64%, 40% in group treated in combination of external radiation and ICR, and 50%, 40% in the group of external radiation therapy alone(P=NS). Five year survival rates by response of radiation therapy in stage IIIa and IIIb were 90%, 66% in responder group, and 10%, 7% in non-responder group (P<0.01). There were statistically no

Iron forbidden lines in tokamak discharges

International Nuclear Information System (INIS)

Suckewer, S.; Hinnov, E.

1979-03-01

Several spectrum lines from forbidden transitions in the ground configurations of highly ionized atoms have been observed in the PLT tokamak discharges. Such lines allow localized observations, in the high-temperature regions of the plasma, of ion-temperatures, plasma motions, and spatial distributions of ions. Measured absolute intensities of the forbidden lines have been compared with simultaneous observations of the ion resonance lines and with model calculations in order to deduce the mechanism of level populaions by means of electron collisions and radiative transitions

Iron forbidden lines in tokamak discharges

Energy Technology Data Exchange (ETDEWEB)

Suckewer, S.; Hinnov, E.

1979-03-01

Several spectrum lines from forbidden transitions in the ground configurations of highly ionized atoms have been observed in the PLT tokamak discharges. Such lines allow localized observations, in the high-temperature regions of the plasma, of ion-temperatures, plasma motions, and spatial distributions of ions. Measured absolute intensities of the forbidden lines have been compared with simultaneous observations of the ion resonance lines and with model calculations in order to deduce the mechanism of level populaions by means of electron collisions and radiative transitions.

The communications in early warning network for radiation monitoring

International Nuclear Information System (INIS)

Oyoun, M.B.; Al-Hussin, Mohamad; Fares, Adnan; Al-Oulabi, Yasser; Othman, Ibrahim

1992-07-01

The objectives of early warning network are: The determination of gamma radiation (background) levels in air which depend on location and time, evaluation of any situation resulting from radiation or nuclear accident out of boarder, and after that reporting the emergency situation to relevant authorities on the national and international levels. Monitoring stations were installed using Gm tubes to cover boarder lines from south to north and east to west as follows: Damascus, Darra, Latakia, Tartous, Aleppo, Kamishly, Ragaa, and Qunitra. The following modes of communication: Telephone line, leased line, direct connection, and Syrian data network were used in the Syrian early network. This project was carried out in cooperation with IAEA under project no. RER/9/003. (author). 22 figs., 1 tab

Water-vapor absorption line measurements in the 940-nm band by using a Raman-shifted dye laser

Science.gov (United States)

Chu, Zhiping; Wilkerson, Thomas D.; Singh, Upendra N.

1993-01-01

We report water-vapor absorption line measurements that are made by using the first Stokes radiation (930-982 nm) with HWHM 0.015/cm generated by a narrow-linewidth, tunable dye laser. Forty-five absorption line strengths are measured with an uncertainty of 6 percent and among them are fourteen strong lines that are compared with previous measurements for the assessment of spectral purity of the light source. Thirty air-broadened linewidths are measured with 8 percent uncertainty at ambient atmospheric pressure with an average of 0.101/cm. The lines are selected for the purpose of temperature-sensitive or temperature-insensitive lidar measurements. Results for these line strengths and linewidths are corrected for broadband radiation and finite laser linewidth broadening effects and compared with the high-resolution transmission molecular absorption.

Neutral Hydrogen and Its Emission Lines in the Solar Corona

Science.gov (United States)

Vial, Jean-Claude; Chane-Yook, Martine

2016-12-01

Since the Lyman-α rocket observations of Gabriel ( Solar Phys. 21, 392, 1971), it has been realized that the hydrogen (H) lines could be observed in the corona and that they offer an interesting diagnostic for the temperature, density, and radial velocity of the coronal plasma. Moreover, various space missions have been proposed to measure the coronal magnetic and velocity fields through polarimetry in H lines. A necessary condition for such measurements is to benefit from a sufficient signal-to-noise ratio. The aim of this article is to evaluate the emission in three representative lines of H for three different coronal structures. The computations have been performed with a full non-local thermodynamic-equilibrium (non-LTE) code and its simplified version without radiative transfer. Since all collisional and radiative quantities (including incident ionizing and exciting radiation) are taken into account, the ionization is treated exactly. Profiles are presented at two heights (1.05 and 1.9 solar radii, from Sun center) in the corona, and the integrated intensities are computed at heights up to five solar radii. We compare our results with previous computations and observations ( e.g. Lα from Ultraviolet Coronal Spectrometer) and find a rough (model-dependent) agreement. Since the Hα line is a possible candidate for ground-based polarimetry, we show that in order to detect its emission in various coronal structures, it is necessary to use a very narrow (less than 2 Å wide) bandpass filter.

Radiation distribution sensor with optical fibers for high radiation fields

International Nuclear Information System (INIS)

Takada, Eiji; Kimura, Atsushi; Hosono, Yoneichi; Takahashi, Hiroyuki; Nakazawa, Masaharu

1999-01-01

Radiation distribution sensors with their feasibilities have been described in earlier works. However, due to large radiation induced transmission losses in optical fibers, especially in the visible wavelength region, it has been difficult to apply these techniques to high radiation fields. In this study, we proposed a new concept of optical fiber based radiation distribution measurements with near infrared (IR) emission. Near IR scintillators were attached to the ends of optical fibers, where the fibers were bundled and connected to an N-MOS line sensor or a cooled CCD camera. From the measurements of each area density, the radiation levels at the positions of the scintillators can be known. The linearity between the gamma dose rate at each scintillator and the registered counts has been examined. For correcting the radiation induced loss effects, we applied the Optical Time Domain Reflectometry technique to measure the loss distribution and from the results, a possibility for correction of the loss effect has been demonstrated. The applicable dose rate range was evaluated to be from 0.1 to 10 3 Gy/h. This system can be a promising tool as a flexible dose rate distribution monitor in radiation facilities like nuclear plants and accelerator facilities. (author)

Radiation shielding technology development for proton linear accelerator

Energy Technology Data Exchange (ETDEWEB)

Lee, Yong Ouk; Lee, Y. O.; Cho, Y. S. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Kim, M. H.; Sin, M. W.; Park, B. I. [Kyunghee Univ., Seoul (Korea, Republic of)] [and others

2005-09-01

This report was presented as an output of 2-year project of the first phase Proton Engineering Frontier Project(PEFP) on 'Radiation Shielding Technology Development for Proton Linear Accelerator' for 20/100 MeV accelerator beam line and facility. It describes a general design concept, provision and update of basic design data, and establishment of computer code system. It also includes results of conceptual and preliminary designs of beam line, beam dump and beam facilities as well as an analysis of air-activation inside the accelerator equipment. This report will guides the detailed shielding design and production of radiation safety analysis report scheduled in the second phase project.

Selection and characterizations of radiation-induced salinity-tolerant lines in rice

International Nuclear Information System (INIS)

Lee, I.S.; Kim, D.S.; Lee, S.J.; Song, H.S.; Lim, Y.P.; Lee, Y.I.

2003-01-01

NaCl tolerant cell lines were selected from irradiated callus, which were generated from seed cultures. M 1 -regenerates were obtained from the salt-tolerant callus cultured on the auxin-free medium for 30 days. Some regenerants were more tolerant than the parent variety (Dongjinbyeo) on a medium containing 0.75 % NaCl. Seeds (M 3 5,000 lines) derived from M 2 lines were grown to the 3 leaf stage. M 3 lines were soaked with a 0.75 % salt solution for 3 weeks and 350 salt-tolerant genotypes were selected. Among the M 3 350 lines, forty tolerant lines were selected from a saline field (10~14 mS) near the sea coast. Of the forty lines, two lines (18-1 and 50-1) showed more improved plant height, panicle length, tillering number, spikelet number and yield than those of the original variety. Thirty primers were screened and two RAPD markers were identified, which appeared in both the salt-tolerant lines (18-1 and 50-1). From DNA-hybridization experiments, it appeared that the fragment arose from the middle-repetitive copy sequences. The transcript involved in the marker showed a higher expression in the salt-tolerant lines than the sensitive lines. The salt-tolerant lines would be useful as a resource for salt-tolerant breeding. (author)

Development of radiation dose assessment system for radiation accident (RADARAC)

International Nuclear Information System (INIS)

Takahashi, Fumiaki; Shigemori, Yuji; Seki, Akiyuki

2009-07-01

The possibility of radiation accident is very rare, but cannot be regarded as zero. Medical treatments are quite essential for a heavily exposed person in an occurrence of a radiation accident. Radiation dose distribution in a human body is useful information to carry out effectively the medical treatments. A radiation transport calculation utilizing the Monte Carlo method has an advantageous in the analysis of radiation dose inside of the body, which cannot be measured. An input file, which describes models for the accident condition and quantities of interest, should be prepared to execute the radiation transport calculation. Since the accident situation, however, cannot be prospected, many complicated procedures are needed to make effectively the input file soon after the occurrence of the accident. In addition, the calculated doses are to be given in output files, which usually include much information concerning the radiation transport calculation. Thus, Radiation Dose Assessment system for Radiation Accident (RADARAC) was developed to derive effectively radiation dose by using the MCNPX or MCNP code. RADARAC mainly consists of two parts. One part is RADARAC - INPUT, which involves three programs. A user can interactively set up necessary resources to make input files for the codes, with graphical user interfaces in a personnel computer. The input file includes information concerning the geometric structure of the radiation source and the exposed person, emission of radiations during the accident, physical quantities of interest and so on. The other part is RADARAC - DOSE, which has one program. The results of radiation doses can be effectively indicated with numerical tables, graphs and color figures visibly depicting dose distribution by using this program. These results are obtained from the outputs of the radiation transport calculations. It is confirmed that the system can effectively make input files with a few thousand lines and indicate more than 20

Title of paper: the induction of P-53 independent programmed cell death (apoptosis) with ionizing radiation and 5-fluorouracil (5-FU) in the HT-29 human colon carcinoma cell line

International Nuclear Information System (INIS)

Blackstock, A. Wm.; Gill, Misha; Hess, Suzanne M.; Fisher, Robert W.; Leadon, Steven A.; Tepper, Joel E.

1996-01-01

fragments in treated cells. Flow cytometry was also used to quantitate cells undergoing apoptosis. Cells were stained with propidium iodine for DNA content and then analyzed on a FACSCAN (Becton Dickinson) to identify the G 0 apoptotic population of cells. Apoptosis was assessed at 24 hours after treatment in all cases. Results: Cells exposed to a 24 hour incubation in 5-FU immediately following irradiation showed increased radiosensitivity in terms of the loss of the shoulder region of the radiation survival curve. In these preliminary data, the induction of apoptosis with ionizing radiation alone at 24 hours was closely associated with increasing dose of radiation up to 5 Gy; a 10% apoptotic fraction was measured in our controls, increasing to 13.5% at 2 Gy, 15% at 5-Gy, and only 12% in cells receiving 10 Gy. Increased apoptosis was clearly observed at lower radiation doses in those cells treated with radiation and 5-FU. 14% of cells treated with 5-FU alone were apoptotic while the maximum apoptotic response, 18%, was observed after treatment with 5-FU immediately following a 2 Gy treatment with radiation. A persistent trend of increasing apoptosis with radiation alone up to 5 Gy but decreasing at 10 Gy was observed. The apoptotic response was consistently greatest following a 2 Gy irradiation in combination with 5-FU, with a return to near control levels at higher doses of radiation, suggesting that all cells capable of undergoing apoptosis do so after 2 Gy. Conclusions: These results show that radiation can initiate programmed cell death via a p53 independent pathway in the HT-29 cell line, and that maximum apoptosis was observed at lower radiation doses with the addition of low doses of 5-FU. These data also suggests that a combination treatment of both radiation and 5-FU results in an increased apoptotic response when compared to radiation alone. Emerging data suggests a persistent apoptotic fraction throughout a fractionated course of radiotherapy, and that apoptosis

Ionizing radiation induced production of tumor necrosis factor α in the Ewing's sarcoma cell line RM 82 in vitro and in vivo

International Nuclear Information System (INIS)

Ruebe, C.; Schaefer, K.L.; Dockhorn-Dworniczak, B.; Willich, N.

1997-01-01

Aim: The expression of cytokines plays an important role in the transmission of the effects of ionizing radiation to tumor cells and normal tissue. Tumor necrosis factor alpha (TNF α), a pleiotropic monokine, is of special interest because of its cytotoxic effect on tumor cells and the induction of hemorrhagic necrosis in tumors. We examined the influence of ionizing radiation on TNF α production in a human Ewing's sarcoma cell line in vitro and in vivo. Methods: The protein and mRNA levels of the Ewing's sarcoma cell line RM 82 were examined in vitro with 'Enhanced Amplified Sensitivity Immunoassay' (EASIA) and semiquantitative RT-PCR before and after treatment with single doses of 2 to 40 Gy, 1 to 72 hours after irradiation. After successful transplantation to nude mice, the time and dose correlation of TNF α mRNA production was examined in vivo. Results: In vitro, RM 82 had a basal protein level of TNF α of 20.1 ± 4.3 pg/ml/10 6 cells. We observed a time- and dose-dependent increase of TNF α expression with a maximum of 125 pg/ml/10 6 (5.9fold) 24 hours after irradiation with 20 Gy. At the mRNA level, the maximal up-regulation occurred 6 to 12 hours after 10 Gy. In vivo, the xenograft tumor maintained the capacity of TNF α expression. Time- and dose-dependency in mRNA production showed a maximum increase 6 hours after treatment with 10 Gy. (orig.) [de

Simulating the Mg II NUV Spectra & C II Resonance Lines During Solar Flares

Science.gov (United States)

Kerr, Graham Stewart; Allred, Joel C.; Leenaarts, Jorrit; Butler, Elizabeth; Kowalski, Adam

2017-08-01

The solar chromosphere is the origin of the bulk of the enhanced radiative output during solar flares, and so comprehensive understanding of this region is important if we wish to understand energy transport in solar flares. It is only relatively recently, however, with the launch of IRIS that we have routine spectroscopic flarea observations of the chromsphere and transition region. Since several of the spectral lines observed by IRIS are optically thick, it is necessary to use forward modelling to extract the useful information that these lines carry about the flaring chromosphere and transition region. We present the results of modelling the formation properties Mg II resonance lines & subordinate lines, and the C II resonance lines during solar flares. We focus on understanding their relation to the physical strucutre of the flaring atmosphere, exploiting formation height differences to determine if we can extract information about gradients in the atmosphere. We show the effect of degrading the profiles to the resolution of the IRIS, and that the usual observational techniques used to identify the line centroid do a poor job in the early stages of the flare (partly due to multiple optically thick line components). Finally, we will tentatively comment on the effects that 3D radiation transfer may have on these lines.

Health survey of radiation workers. Results of questionnaire

International Nuclear Information System (INIS)

Morikawa, Kaoru; Aoyama, Takashi; Kawagoe, Yasumitsu; Sunayashiki, Tadashi; Tanaka, Kiyoshi; Nishitani, Motohiro; Yoshinaga, Nobuharu

1998-01-01

The Japanese Society of Radiological Technology asked radiation workers about the radiation doses and the state of their health as well as family. The reports by the Health and Welfare Ministry were referenced to compare radiation workers with others. The questionnaire was sent to about 4,000 members, and returned from 2,479. The survey showed that 684 persons (27.6%) felt health anxiety, 455 persons (18.4%) had medical check for recent one year, and 1,645 persons (66.4%) had anamnesis. Radiation doses for one year and cumulated doses varied according to engaging duration. (K.H.)

SU-G-TeP3-10: Radiation Induces Prompt Live-Cell Metabolic Fluxes

Energy Technology Data Exchange (ETDEWEB)

Campos, D [University of Wisconsin Madison, Madison, WI (United States); Peeters, W; Bussink, J [Radboud University Medical Center, Nijmegen, GA (United States); Nickel, K [University of Wisconsin - Madison, Madison, Wisconsin (United States); Burkel, B; Kimple, R; Kogel, A van der; Eliceiri, K [University of Wisconsin - Madison, Madison, WI (United States); Kissick, M [University of Wisconsin, Madison, WI (United States)

2016-06-15

Purpose: To compare metabolic dynamics and HIF-1α expression following radiation between a cancerous cell line (UM-SCC-22B) and a normal, immortalized cell line, NOK (Normal Oral Keratinocyte). HIF-1 is a key factor in metabolism and radiosensitivity. A better understanding of how radiation affects the interplay of metabolism and HIF-1 might give a better understanding of the mechanisms responsible for radiosensitivity. Methods: Changes in cellular metabolism in response to radiation are tracked by fluorescence lifetime of NADH. Expression of HIF-1α was measured by immunofluorescence for both cell lines with and without irradiation. Radiation response is also monitored with additional treatment of a HIF-1α inhibitor (chrysin) as well as a radical scavenger (glutathione). Changes in oxygen consumption and respiratory capacity are also monitored using the Seahorse XF analyzer. Results: An increase in HIF-1α was found to be in response to radiation for the cancer cell line, but not the normal cell line. Radiation was found to shift metabolism toward glycolytic pathways in cancer cells as measured by oxygen consumption and respiratory capacity. Radiation response was found to be muted by addition of glutathione to cell media. HIF-1α inhibition similarly muted radiation response in cancer. Conclusion: The HIF-1 protein complex is a key regulator cellular metabolism through the regulation of glycolysis and glucose transport enzymes. Moreover, HIF-1 has shown radio-protective effects in tumor vascular endothelia, and has been implicated in metastatic aggression. Monitoring interplay between metabolism and the HIF-1 protein complex can give a more fundamental understanding of radiotherapy response.

SU-G-TeP3-10: Radiation Induces Prompt Live-Cell Metabolic Fluxes

International Nuclear Information System (INIS)

Campos, D; Peeters, W; Bussink, J; Nickel, K; Burkel, B; Kimple, R; Kogel, A van der; Eliceiri, K; Kissick, M

2016-01-01

Purpose: To compare metabolic dynamics and HIF-1α expression following radiation between a cancerous cell line (UM-SCC-22B) and a normal, immortalized cell line, NOK (Normal Oral Keratinocyte). HIF-1 is a key factor in metabolism and radiosensitivity. A better understanding of how radiation affects the interplay of metabolism and HIF-1 might give a better understanding of the mechanisms responsible for radiosensitivity. Methods: Changes in cellular metabolism in response to radiation are tracked by fluorescence lifetime of NADH. Expression of HIF-1α was measured by immunofluorescence for both cell lines with and without irradiation. Radiation response is also monitored with additional treatment of a HIF-1α inhibitor (chrysin) as well as a radical scavenger (glutathione). Changes in oxygen consumption and respiratory capacity are also monitored using the Seahorse XF analyzer. Results: An increase in HIF-1α was found to be in response to radiation for the cancer cell line, but not the normal cell line. Radiation was found to shift metabolism toward glycolytic pathways in cancer cells as measured by oxygen consumption and respiratory capacity. Radiation response was found to be muted by addition of glutathione to cell media. HIF-1α inhibition similarly muted radiation response in cancer. Conclusion: The HIF-1 protein complex is a key regulator cellular metabolism through the regulation of glycolysis and glucose transport enzymes. Moreover, HIF-1 has shown radio-protective effects in tumor vascular endothelia, and has been implicated in metastatic aggression. Monitoring interplay between metabolism and the HIF-1 protein complex can give a more fundamental understanding of radiotherapy response.

Evaluate The Fluctuation Of Phytic Acid Content In Seed From Mutant Lines By Gamma Ray

International Nuclear Information System (INIS)

Nguyen Thi Lang; Pham Van Ut

2011-01-01

Phytic acid is a molecule composed of myo-inositol 1,2,3,4,5,6 hexakis dihydrogen phosphate (Ins P6), a major component in the source of phosphorus (P) reserves of about 50 plants - 80% of total seed phosphorus (Lott, 1984). At physiological pH in the form of phytic acid have negatively charged ions hold together the complex mineral nutrition creates indigestion. Moreover, phosphorus in the form of phytate or phytic humans and monogastric animals can not absorb, are all discharged polluted environment transitions. In rice OM819, OM4900, OM3536, D4 and D8 are irradiated with gamma rays at 5 doses: 100, 200, 300, 400 and 500 Gy to create mutant strains with low levels of phytic acid. Results in radiation levels may appear 100 Gy line grain phytic acid expression is low. At the level 200 Gy of radiation is three populations OM819, OM4900 and OM3536 with 8 lines for grain phytic acid expression is low. At 300 Gy extent, appeared seven lines with low nuclear expression of phytic acid 4 populations OM819, OM4900, OM3536 and D4. At the level 400 Gy of radiation there are 4 populations appear only 5 lines expressed low phytic acid, with 3-line expression levels 3 and 2 lines with level 4 expression. At the level of radiation 500 Gy only one line appears at level 3 of phytic acid this is OM819 populations. For genotype analysis using marker RM 261 with 66.67% of the rice low phytic acid content of the expression analysis of biochemical polymorphisms. (author)

Lodging resistant pea line derived after mutagenic treatment

International Nuclear Information System (INIS)

Naidenova, N.; Vassilevska-Ivanova, R.

2006-01-01

Line 1/502 is a new lodging resistant pea ( Pisum sativum L.) developed for the Bulgarian field pea industry. This line is a direct chlorophyll mutant, which originates after treatment of the initial line, cultivar Auralia, with 150 Gy 60 Co γ - radiation. In regional evaluation trials conducted in Sofia over seven successive seasons 1/502 has revealed improved standing ability that most probably is a result from modification of the architecture of the plants appearing in reduction of plant height. The agronomic and morphological characteristics of the mutant line were reported. The upright plant habit and resistance to lodging is especially beneficial for production of high quality peas because pods are held above the soil surface during crop development and during maturity which aids in keeping the peas clean and free of pathogens that can cause discoloration and rotting. (authors)

Plasma radiation in tokamak disruption simulation experiments

International Nuclear Information System (INIS)

Arkhipov, N.; Bakhtin, V.; Safronov, V.; Toporkov, D.; Vasenin, S.; Zhitlukhin, A.; Wuerz, H.

1995-01-01

Plasma impact results in sudden evaporation of divertor plate material and produces a plasma cloud which acts as a protective shield. The incoming energy flux is absorbed in the plasma shield and is converted mainly into radiation. Thus the radiative characteristics of the target plasma determine the dissipation of the incoming energy and the heat load at the target. Radiation of target plasma is studied at the two plasma gun facility 2MK-200 at Troitsk. Space- and time-resolved spectroscopy and time-integrated space-resolved calorimetry are employed as diagnostics. Graphite and tungsten samples are exposed to deuterium plasma streams. It is found that the radiative characteristics depend strongly on the target material. Tungsten plasma arises within 1 micros close to the surface and shows continuum radiation only. Expansion of tungsten plasma is restricted. For a graphite target the plasma shield is a mixture of carbon and deuterium. It expands along the magnetic field lines with a velocity of v = (3--4) 10 6 cm/s. The plasma shield is a two zone plasma with a hot low dense corona and a cold dense layer close to the target. The plasma corona emits intense soft x-ray (SXR) line radiation in the frequency range from 300--380 eV mainly from CV ions. It acts as effective dissipation system and converts volumetrically the incoming energy flux into SXR radiation

Results of the Association of Directors of Radiation Oncology Programs (ADROP) Survey of Radiation Oncology Residency Program Directors

International Nuclear Information System (INIS)

Harris, Eleanor; Abdel-Wahab, May; Spangler, Ann E.; Lawton, Colleen A.; Amdur, Robert J.

2009-01-01

Purpose: To survey the radiation oncology residency program directors on the topics of departmental and institutional support systems, residency program structure, Accreditation Council for Graduate Medical Education (ACGME) requirements, and challenges as program director. Methods: A survey was developed and distributed by the leadership of the Association of Directors of Radiation Oncology Programs to all radiation oncology program directors. Summary statistics, medians, and ranges were collated from responses. Results: Radiation oncology program directors had implemented all current required aspects of the ACGME Outcome Project into their training curriculum. Didactic curricula were similar across programs nationally, but research requirements and resources varied widely. Program directors responded that implementation of the ACGME Outcome Project and the external review process were among their greatest challenges. Protected time was the top priority for program directors. Conclusions: The Association of Directors of Radiation Oncology Programs recommends that all radiation oncology program directors have protected time and an administrative stipend to support their important administrative and educational role. Departments and institutions should provide adequate and equitable resources to the program directors and residents to meet increasingly demanding training program requirements.

The influence of static fields on the dynamic Stark spectra of hydrogen Balmer lines

International Nuclear Information System (INIS)

Janssen, G.C.A.M.; Jayakumar, R.; Granneman, E.H.A.

1981-01-01

In plasmas atomic-line radiation is influenced by static and high frequency fields. A simple method of calculating the Stark profiles of the Balmer α and β lines for the case of one-dimensional fields is discussed. Using a Holtsmark field for the static component, the resulting profile of Balmer α shows a splitting of the satellites. (author)

Characteristics of radiation field in living environment, 2

International Nuclear Information System (INIS)

Nagaoka, Toshi; Sakamoto, Ryuichi; Tsutsumi, Masahiro; Saito, Kimiaki; Moriuchi, Shigeru

1990-01-01

A series of environmental radiation survey was carried out on train lines within Tokyo metropolitan area to clarify the characteristics of radiation field in living environment. Eleven JR, 18 private and 10 subway lines were surveyed, which cover 97% of whole train lines in Tokyo district in terms of annual number of passengers. The characteristics of environmental radiation field on train lines were discussed. The mean absorbed dose rate in air due to γ-rays on the subway lines was higher than those on the JR and private lines. It is due to the difference in the radioactivity concentration and the distribution of surrounding materials as the γ-ray sources. On the other hand, the mean dose rate due to cosmic-rays on the subway lines was lower than those on the JR and private lines. It is due to the shielding effect of the upper materials such as soil or building materials of tunnels. The mean dose rates for the JR, private and subway lines were calculated using these obtained data. Though the ratio of mean dose rate of γ-rays to that of cosmic-rays for the subway lines was different from those for the JR and private lines, the sum of γ- and cosmic-ray dose rates for the JR, private and subway lines were comparable, 40∼50 nGy/h for any of them. These data will be useful for a precise and realistic evaluation of collective dose, considering the life style of the public and the variation characteristics of environmental radiation. (author)

Analysis of a Kalman filter based method for on-line estimation of atmospheric dispersion parameters using radiation monitoring data

DEFF Research Database (Denmark)

Drews, Martin; Lauritzen, Bent; Madsen, Henrik

2005-01-01

A Kalman filter method is discussed for on-line estimation of radioactive release and atmospheric dispersion from a time series of off-site radiation monitoring data. The method is based on a state space approach, where a stochastic system equation describes the dynamics of the plume model...... parameters, and the observables are linked to the state variables through a static measurement equation. The method is analysed for three simple state space models using experimental data obtained at a nuclear research reactor. Compared to direct measurements of the atmospheric dispersion, the Kalman filter...... estimates are found to agree well with the measured parameters, provided that the radiation measurements are spread out in the cross-wind direction. For less optimal detector placement it proves difficult to distinguish variations in the source term and plume height; yet the Kalman filter yields consistent...

Density dependence of line intensities and application to plasma diagnostics

International Nuclear Information System (INIS)

Masai, Kuniaki.

1993-02-01

Electron density dependence of spectral lines are discussed in view of application to density diagnostics of plasmas. The dependence arises from competitive level population processes, radiative and collisional transitions from the excited states. Results of the measurement on tokamak plasmas are presented to demonstrate the usefulness of line intensity ratios for density diagnostics. Also general characteristics related to density dependence are discussed with atomic-number scaling for H-like and He-like systems to be helpful for application to higher density plasmas. (author)

Effects of γ-radiation on cell growth, cell cycle and promoter methylation of 22 cell cycle genes in the 1321NI astrocytoma cell line.

Science.gov (United States)

Alghamian, Yaman; Abou Alchamat, Ghalia; Murad, Hossam; Madania, Ammar

2017-09-01

DNA damage caused by radiation initiates biological responses affecting cell fate. DNA methylation regulates gene expression and modulates DNA damage pathways. Alterations in the methylation profiles of cell cycle regulating genes may control cell response to radiation. In this study we investigated the effect of ionizing radiation on the methylation levels of 22 cell cycle regulating genes in correlation with gene expression in 1321NI astrocytoma cell line. 1321NI cells were irradiated with 2, 5 or 10Gy doses then analyzed after 24, 48 and 72h for cell viability using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliu bromide) assay. Flow cytometry were used to study the effect of 10Gy irradiation on cell cycle. EpiTect Methyl II PCR Array was used to identify differentially methylated genes in irradiated cells. Changes in gene expression was determined by qPCR. Azacytidine treatment was used to determine whether DNA methylation affectes gene expression. Our results showed that irradiation decreased cell viability and caused cell cycle arrest at G2/M. Out of 22 genes tested, only CCNF and RAD9A showed some increase in DNA methylation (3.59% and 3.62%, respectively) after 10Gy irradiation, and this increase coincided with downregulation of both genes (by 4 and 2 fold, respectively). with azacytidine confirmed that expression of CCNF and RAD9A genes was regulated by methylation. 1321NI cell line is highly radioresistant and that irradiation of these cells with a 10Gy dose increases DNA methylation of CCNF and RAD9A genes. This dose down-regulates these genes, favoring G2/M arrest. Copyright © 2017 Medical University of Bialystok. Published by Elsevier B.V. All rights reserved.

Reverse resistance to radiation in KYSE-150R esophageal carcinoma cell after epidermal growth factor receptor signal pathway inhibition by cetuximab

International Nuclear Information System (INIS)

Jing Zhao; Gong Ling; Xie Congying; Zhang Li; Su Huafang; Deng Xia; Wu Shixiu

2009-01-01

Background and purpose: The purpose of our study is to examine the capacity of cetuximab to reverse radiation resistance and investigate molecular mechanisms in human radiation-resistant esophageal carcinoma cell line KYSE-150R. Materials and methods: The radioresistant cell line KYSE-150R was established by using fractionated irradiation (FIR). The KYSE-150R cell line was exposed to radiation, treatment with cetuximab, and combined treatment. Cell cycle distribution and apoptosis were analyzed using flow cytometry. Radiation survival was analyzed using clonogenic assays. RT 2 profiler TM PCR array was performed to analyze EGF/PDGF signaling pathway genes. Results: The established esophageal carcinoma cell line KYSE-150R showed higher radioresistance than parental cell line. Cetuximab could reverse the radiation resistance of KYSE-150R cells. Cell cycle analysis showed that combination with radiation and cetuximab resulted in the accumulation of cells in G1 and G2/M phases, with the reduction of cells within the S phase. Cetuximab enhanced the apoptosis induced by radiation. RT 2 profiler TM array showed that some intracellular signaling genes deriving from EGF/PDGF signaling pathway regulated by cetuximab. Conclusions: Irradiation combined with EGFR blocked by cetuximab may reverse the resistance to radiation in radioresistant esophageal carcinoma cell. The mechanisms may include cell cycle perturbation and enhancement of radiation-induced apoptosis. Further studies are needed to evaluate the role of cetuximab in combination with radiotherapy in the management of esophageal carcinoma.

The effects of combining ionizing radiation and adenovirus-mediated p53 gene transfer in human nasopharyngeal carcinoma cell lines

International Nuclear Information System (INIS)

Liu Feifei; Li Jianhua; Lax, Stuart; Klamut, Henry

1997-01-01

Purpose/Objective: We have previously demonstrated that the introduction of human recombinant wild-type p53 carried by the adenoviral vector (Ad5CMV-p53) into two human nasopharyngeal carcinoma (NPC) cell lines (CNE-1 and CNE-2Z) resulted in significant cytotoxicity. In the current work, we wanted to evaluate the results of this strategy when combined with ionizing radiation (XRT). Materials and Methods: CNE-1, CNE-2Z, and a normal human nasopharyngeal fibroblast strain KS1, were infected with iso-effective doses of 2, 6 and 6 pfu/cell of Ad5CMV-p53 respectively. XRT was administered 24 hours post-infection, to coincide with the time of maximal recombinant p53 expression. Western blot analyses were conducted for p53, p21 WAF1/CIP1 , bax and bcl-2. Cell viability was evaluated using both the MTT and clonogenic assays. Presence of apoptosis was determined by using DNA agarose gel electrophoresis. Results: We observed that the combination of Ad5CMV-p53 + XRT (2, 4, and 6 Gy) resulted in an approximately 1-log greater level of cytotoxicity compared to that observed with XRT alone for both NPC cell lines. The MTT assay indicated sparing of the KS1 cells when subjected to the identical treatments. XRT alone stimulated minimal p53 expression; Ad5CMV-p53 alone induced significant recombinant p53 expression, which was not further enhanced by the addition of XRT. Similar observations were made for p21 WAF1/CIP1 expression. No changes were observed for bax and bcl-2 expression with any of these treatments. Apoptosis was induced following 4 Gy of XRT alone, but was observed earlier, at 2 Gy when combined with Ad5CMV-p53. Conclusion: Additional cytotoxicity was observed for the NPC cell lines when XRT was combined with Ad5CMV-p53 infection, with concurrent sparing of normal cells (KS1). This cytotoxicity also appeared to be mediated through the induction of the apoptotic pathway. These results support our previous observation of the potential application of this strategy in the

Result of radiation therapy for inoperable pancreas cancer

International Nuclear Information System (INIS)

Okawa, Tomohiko; Ikeda, Michio; Tazaki, Eisei; Kaneda, Koichi; Tsuya, Akira.

1978-01-01

Twenty cases of the pancreas cancer were treated by means of 60 Co γ or Linac x-rays during the period between 1958 and 1977 at the Cancer Institute Hospital and Tokyo Women's Medical College. 11 were irradiated by external radiation and 9 by intraoperative radiation. Pancreas irradiation was indicated for relief of pain and alleviation of jaundice although the effect was symptomatic. 2500 rad of intraoperative radiation was reasonable dose in about 10 x 10 cm radiation field. Radical curative irradiation for pancreas cancer might be rarely indicated. Radiotherapy of pancreas cancer should be considered in conjunction with multimodal treatment in the future. (author)

No adaptive response is induced by chronic low-dose radiation from Ra-226 in the CHSE/F fish embryonic cell line and the HaCaT human epithelial cell line

Energy Technology Data Exchange (ETDEWEB)

Shi, Xiaopei, E-mail: shix22@mcmaster.ca; Mothersill, Carmel; Seymour, Colin

2016-11-15

Purpose: To determine whether chronic low-dose α-particle radiation from Ra-226 over multiple cell generations can lead to an adaptive response in CHSE/F fish embryonic cells or HaCaT human epithelial cells receiving subsequent acute high-dose γ-ray radiation. Methods: CHSE/F and HaCaT cells were exposed to very low doses of Ra-226 in medium for multiple generations prior to being challenged by a higher dose γ-ray radiation. The clonogenic assay was used to test the clonogenic survival of cells with or without being pretreated by radiation from Ra-226. Results: In general, pretreatment with chronic radiation has no significant influence on the reaction of cells to the subsequent challenge radiation. Compared to unprimed cells, the change in clonogenic survival of primed cells after receiving challenge radiation is mainly due to the influence of the chronic exposure, and there's little adaptive response induced. However at several dose points, pretreatment of CHSE/F fish cells with chronic radiation resulted in a radiosensitive response to a challenge dose of γ-ray radiation, and pretreatment of HaCaT cells resulted in no effect except for a slightly radioresistant response to the challenge radiation which was not significant. Conclusion: The results suggest that chronic low-dose radiation is not effective enough to induce adaptive response. There was a difference between human and fish cells and it may be important to consider results from multiple species before making conclusions about effects of chronic or low doses of radiation in the environment. The term “radiosensitive” or “adaptive” make no judgment about whether such responses are ultimately beneficial or harmful. - Highlights: • No obvious adaptive response is induced by chronic low-dose radiation from Ra-226. • Priming radiation from Ra-226 sensitized CHSE/F cells to the challenge radiation. • Linear model is inconsistent with current work using chronic low-dose radiation.

LOW-METALLICITY PROTOSTARS AND THE MAXIMUM STELLAR MASS RESULTING FROM RADIATIVE FEEDBACK: SPHERICALLY SYMMETRIC CALCULATIONS

International Nuclear Information System (INIS)

Hosokawa, Takashi; Omukai, Kazuyuki

2009-01-01

The final mass of a newborn star is set at the epoch when the mass accretion onto the star is terminated. We study the evolution of accreting protostars and the limits of accretion in low-metallicity environments under spherical symmetry. Accretion rates onto protostars are estimated via the temperature evolution of prestellar cores with different metallicities. The derived rates increase with decreasing metallicity, from M-dot≅10 -6 M odot yr -1 at Z = Z sun to 10 -3 M sun yr -1 at Z = 0. With the derived accretion rates, the protostellar evolution is numerically calculated. We find that, at lower metallicity, the protostar has a larger radius and reaches the zero-age main sequence (ZAMS) at higher stellar mass. Using this protostellar evolution, we evaluate the upper stellar mass limit where the mass accretion is hindered by radiative feedback. We consider the effects of radiation pressure exerted on the accreting envelope, and expansion of an H II region. The mass accretion is finally terminated by radiation pressure on dust grains in the envelope for Z ∼> 10 -3 Z sun and by the expanding H II region for lower metallicity. The mass limit from these effects increases with decreasing metallicity from M * ≅ 10 M sun at Z = Z sun to ≅300 M sun at Z = 10 -6 Z sun . The termination of accretion occurs after the central star arrives at the ZAMS at all metallicities, which allows us to neglect protostellar evolution effects in discussing the upper mass limit by stellar feedback. The fragmentation induced by line cooling in low-metallicity clouds yields prestellar cores with masses large enough that the final stellar mass is set by the feedback effects. Although relaxing the assumption of spherical symmetry will alter feedback effects, our results will be a benchmark for more realistic evolution to be explored in future studies.

Grain product of 34 soya mutant lines

International Nuclear Information System (INIS)

Salmeron E, J.; Mastache L, A. A.; Valencia E, F.; Diaz V, G. E.; Cervantes S, T.; De la Cruz T, E.; Garcia A, J. M.; Falcon B, T.; Gatica T, M. A.

2009-01-01

This work was development with the objective of obtaining information of the agronomic behavior of 34 soya mutant lines (R 4 M 18 ) for human consumption and this way to select the 2 better lines. The genetic materials were obtained starting from the variety ISAAEG-B M2 by means of the application of recurrent radiation with Co 60 gammas, to a dose of 350 Gray for the first two generations and both later to 200 Gray and selection during 17 cycles, being obtained the 34 better lines mutants with agronomic characteristic wanted and good flavor. The obtained results were that the mutant lines L 25 and L 32 produced the major quantity in branches/plant number with 7.5 and 7.25, pods/plant number with 171.25 and 167, grains/plant number with 350.89 and 333.07 and grain product (ton/ha) to 15% of humidity 5.15 and 4.68 ton/ha, respectively. (Author)

Report of questionnaire result concerning the radiation control in medicare facilities

International Nuclear Information System (INIS)

Nakamura, Yutaka

2009-01-01

Radiation control in Japanese medicare facilities is regulated generally by multiple laws of radiation and the Committee has investigated their actual radiation control practice through questionnaire, of which result and its analysis are described here. The questionnaire on web (Committee's homepage) was conducted in the period Apr., 13-May, 1, 2009, by asking to medical radiology personnel (MRP) with 20 items, mainly about personnel working for radiation medicare (RM), monitoring of their external dose, notice of exposure dose to individual person, archiving of the dose record, and questions about the Law Concerning Prevention from Radiation Hazard due to Radioisotopes, Etc.; was answered by 378 facilities where 15,281 persons in total worked for RM (41/facility in average); and the facilities were under regulation by 1 (Medical, 39%) and 2 (Medical and for Prevention, 61%) laws. Major findings were: 71% of facilities had no clear rule to select MRP; 98% trusted dosimetry outside; in 76%, personnel participating in RM had pocket dosimeter as well; 70% investigated the exposure history at personnel employment; to personnel whose dose could exceed or exceeded 20 mSv/y, 45% transferred the person to other work site, 34% issued warning and 21% had no such personnel; 73% felt the necessity of qualified expert for radiation control; 81% conducted education and training to MRP; 54% used radiation-generating equipments, 27%, unsealed radioisotopes and 19%, sealed ones; and 77% felt the radiation control should be unified in the Medical Law. Based on the findings, the Committee discussed and commented about definition and selection of MRP, dosimetry and its record of MRP having multiple, increasing works, uncertainty of the exact number of MRP in Japan, and desirable unification of radiation control practice in the medicare facility into the Medical Law if amended in future. (K.T.)

Los resonance lines in promethiumlike heavy ions

International Nuclear Information System (INIS)

Nakamura, Nobuyuki; Kobayashi, Yusuke; Kato, Daiji; Sakaue, Hiroyuki A.; Murakami, Izumi

2016-01-01

Identifying the ns - np resonance lines in alkali-metal-like ions is an important issue in fusion plasma science in the view of spectroscopic diagnostics and radiation power loss. Whereas for n=2, 3 and 4 these resonances are prominent and well studied, so far no one could clearly identify the resonance lines for n=5 in the promethiumlike sequence. We have now experimentally clarified the reason for the 'lost resonance lines. In the present study, highly-charged bismuth ions have been studied using a compact electron beam ion trap (EBIT). Extreme ultraviolet emission from the bismuth ions produced and trapped in the EBIT is observed with a grazing-incidence flat-field spectrometer. The energy dependent spectra are compared with a collisional-radiative model calculation, and we show that the 5s - 5p resonance lines are very weak in plasma with a wide range of electron density due to the presence of a long-lived metastable state. (author)

The change of p16 gene expression in glioma cell line C6 after radiation with gamma knife

International Nuclear Information System (INIS)

Zhao Xingli; Zhao Conghai; Tian Yu

2002-01-01

Objective: T observe the change of expression of p16 gene product, P16 protein, after treated by gamma knife on glioma cell line C6. Methods: Glioma C6 cells proliferated in vitro, treated by γ-knife in dose of 5.00 and 6.22 Gy, respectively. P16 protein was detected by immunohistochemical technique and image analysis. Results: The P16 protein in glioma C6 cells was notably increased after treatment with γ knife (P < 0.01). The grey number in C6 group (control group) was 167.1 +- 6.2 and was 155.4 +- 2.0 and 124.9 +- 7.1, respectively, in 5.00 Gy and 6.22 Gy gamma knife treated group. Conclusion: It is suggests that one of the mechanisms of glioma cell C6 apoptosis induced by γ-knife radiation may be associated with activation of p16 gene and increase of P16 protein expression

Submillimeter and far-infrared line observations of M17 SW - A clumpy molecular cloud penetrated by ultraviolet radiation

Science.gov (United States)

Stutzki, J.; Genzel, R.; Harris, A. I.; Stacey, G. J.; Jaffe, D. T.

1988-01-01

Millimeter, submillimeter, and far-IR spectroscopic observations of the M17 SW star formation region are reported. Strong forbidden C II 158 micron and CO J = 7 - 6 line emission arises in an H II region/molecular cloud interface of several pc thickness. Weaker forbidden C II emission appears to be extended over 15 pc throughout the molecular cloud. CO J = 14 - 13 and forbidden O I 145 micron spectra indicate high temperatures and densities for both molecular and atomic gas in the interface. The results require the molecular cloud near the interface to be clumpy or filamentary. The extended forbidden C II emission throughout the molecular cloud has a level around 20 times higher than expected from a single molecular cloud interface exposed to an ultraviolet radiation field typical of the solar neighborhood. The high gas temperature of molecular material in the UV-illuminated interface region suggests that CO self-shielding and heating of CO by photoelectrons are important.

An Exact Line Integral Representation of the Physical Optics Far Field from Plane PEC Scatterers Illuminnated by Hertzian Dipoles

DEFF Research Database (Denmark)

Arslanagic, Samel; Meincke, Peter; Jørgensen, Erik

2003-01-01

We derive a line integral representation of the physical optics scattered far field that yields the exact same result as the conventional surface radiation integral. This representation applies to a perfectly electrically conducting plane scatterer illuminated by electric or magnetic Hertzian...... dipoles. The source and observation points can take on almost arbitrary positions. To illustrate the exactness and efficiency of the new line integral, numerical comparisons with the conventional surface radiation integral are carried out....

Mometasone Furoate Cream Reduces Acute Radiation Dermatitis in Patients Receiving Breast Radiation Therapy: Results of a Randomized Trial

International Nuclear Information System (INIS)

Hindley, Andrew; Zain, Zakiyah; Wood, Lisa; Whitehead, Anne; Sanneh, Alison; Barber, David; Hornsby, Ruth

2014-01-01

Purpose: We wanted to confirm the benefit of mometasone furoate (MF) in preventing acute radiation reactions, as shown in a previous study (Boström et al, Radiother Oncol 2001;59:257-265). Methods and Materials: The study was a double-blind comparison of MF with D (Diprobase), administered daily from the start of radiation therapy for 5 weeks in patients receiving breast radiation therapy, 40 Gy in 2.67-Gy fractions daily over 3 weeks. The primary endpoint was mean modified Radiation Therapy Oncology Group (RTOG) score. Results: Mean RTOG scores were significantly less for MF than for D (P=.046). Maximum RTOG and mean erythema scores were significantly less for MF than for D (P=.018 and P=.012, respectively). The Dermatology Life Quality Index (DLQI) score was significantly less for MF than for D at weeks 4 and 5 when corrected for Hospital Anxiety and Depression (HAD) questionnaire scores. Conclusions: MF cream significantly reduces radiation dermatitis when applied to the breast during and after radiation therapy. For the first time, we have shown a significantly beneficial effect on quality of life using a validated instrument (DLQI), for a topical steroid cream. We believe that application of this cream should be the standard of care where radiation dermatitis is expected

Mometasone Furoate Cream Reduces Acute Radiation Dermatitis in Patients Receiving Breast Radiation Therapy: Results of a Randomized Trial

Energy Technology Data Exchange (ETDEWEB)

Hindley, Andrew, E-mail: andrew.hindley@lthtr.nhs.uk [Rosemere Cancer Centre, Royal Preston Hospital, Preston (United Kingdom); Zain, Zakiyah [College of Arts and Sciences, Universiti Utara Malaysia, Kedah (Malaysia); Wood, Lisa [Department of Social Sciences, Lancaster Medical School, Lancaster (United Kingdom); Whitehead, Anne [Medical and Pharmaceutical Statistics Research Unit, Lancaster University, Lancaster (United Kingdom); Sanneh, Alison; Barber, David; Hornsby, Ruth [Rosemere Cancer Centre, Royal Preston Hospital, Preston (United Kingdom)

2014-11-15

Purpose: We wanted to confirm the benefit of mometasone furoate (MF) in preventing acute radiation reactions, as shown in a previous study (Boström et al, Radiother Oncol 2001;59:257-265). Methods and Materials: The study was a double-blind comparison of MF with D (Diprobase), administered daily from the start of radiation therapy for 5 weeks in patients receiving breast radiation therapy, 40 Gy in 2.67-Gy fractions daily over 3 weeks. The primary endpoint was mean modified Radiation Therapy Oncology Group (RTOG) score. Results: Mean RTOG scores were significantly less for MF than for D (P=.046). Maximum RTOG and mean erythema scores were significantly less for MF than for D (P=.018 and P=.012, respectively). The Dermatology Life Quality Index (DLQI) score was significantly less for MF than for D at weeks 4 and 5 when corrected for Hospital Anxiety and Depression (HAD) questionnaire scores. Conclusions: MF cream significantly reduces radiation dermatitis when applied to the breast during and after radiation therapy. For the first time, we have shown a significantly beneficial effect on quality of life using a validated instrument (DLQI), for a topical steroid cream. We believe that application of this cream should be the standard of care where radiation dermatitis is expected.

Logarithmic solution to the line-polygon intersection problem. 127

International Nuclear Information System (INIS)

Siddon, R.L.; Barth, N.H.

1987-01-01

Algorithmic solution for a special case of the line - polygon intersection problem has been developed. The special case involves repeated solution to the problem where one point on the line is held fixed and the other allowed to vary. In addition, the fixed point on the line must lie outside the rectangle defined by the extrema of the polygon and varying point. In radiotherapy applications, the fixed point corresponds to the source of radiation, whereas the varying points refer to the grid of multiple calculation points. For smooth contours of 100-200 vertices, it is found that the new algorithm results in a CPU savings of approximately a factor of 3-5. 3 refs.; 4 figs

The Radiation Effect to Waste Glass that Resulting of Vitrification

International Nuclear Information System (INIS)

Herlan Martono; Aisyah

2002-01-01

The high level liquid waste (HLLW) is generated from the first step extraction of the nuclear fuel reprocessing. This waste was contain of few of actinide and many of fission product. The alpha radiation of actinide that contain on the HLLW cause the change the waste glass characteristic. The experiment was conducted by the doping, irradiation and heating of waste glass resulting from vitrification. The alpha radiation cause the change of composition that could be detected from change of waste glass density and mechanical strength. The increasing of alpha radiation dose cause the increasing change of density and mechanical strength, although the change of mechanical strength is not significant. Degree of change of waste glass density also depend on type of waste-glass and reach for saturated point at over of 5x10 24 alpha decay/m 3 . The gamma radiation of fission product that contain on the HLLW can increasing of waste glass temperature that cause the structure change, so devitrification was occur. The devitrification can the increasing of leaching rate. The cumulative of gamma dose rate was not cause the devitrification. (author)

Infrared radiation models for atmospheric ozone

Science.gov (United States)

Kratz, David P.; Ces, Robert D.

1988-01-01

A hierarchy of line-by-line, narrow-band, and broadband infrared radiation models are discussed for ozone, a radiatively important atmospheric trace gas. It is shown that the narrow-band (Malkmus) model is in near-precise agreement with the line-by-line model, thus providing a means of testing narrow-band Curtis-Godson scaling, and it is found that this scaling procedure leads to errors in atmospheric fluxes of up to 10 percent. Moreover, this is a direct consequence of the altitude dependence of the ozone mixing ratio. Somewhat greater flux errors arise with use of the broadband model, due to both a lesser accuracy of the broadband scaling procedure and to inherent errors within the broadband model, despite the fact that this model has been tuned to the line-by-line model.

Augmentation of Radiation Response by Panitumumab in Models of Upper Aerodigestive Tract Cancer

International Nuclear Information System (INIS)

Kruser, Tim J.; Armstrong, Eric A.; Ghia, Amol J.; Huang Shyhmin; Wheeler, Deric L.; Radinsky, Robert; Freeman, Daniel J.; Harari, Paul M.

2008-01-01

Purpose: To examine the interaction between panitumumab, a fully human anti-epidermal growth factor receptor monoclonal antibody, and radiation in head-and-neck squamous cell carcinoma and non-small-cell lung cancer cell lines and xenografts. Methods and Materials: The head-and-neck squamous cell carcinoma lines UM-SCC1 and SCC-1483, as well as the non-small-cell lung cancer line H226, were studied. Tumor xenografts in athymic nude mice were used to assess the in vivo activity of panitumumab alone and combined with radiation. In vitro assays were performed to assess the effect of panitumumab on radiation-induced cell signaling, apoptosis, and DNA damage. Results: Panitumumab increased the radiosensitivity as measured by the clonogenic survival assay. Radiation-induced epidermal growth factor receptor phosphorylation and downstream signaling through mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 3 (STAT3) was inhibited by panitumumab. Panitumumab augmented radiation-induced DNA damage by 1.2-1.6-fold in each of the cell lines studied as assessed by residual γ-H 2 AX foci after radiation. Radiation-induced apoptosis was increased 1.4-1.9-fold by panitumumab, as evidenced by Annexin V-fluorescein isothiocyanate staining and flow cytometry. In vivo, the combination therapy of panitumumab and radiation was superior to panitumumab or radiation alone in the H226 xenografts (p = 0.01) and showed a similar trend in the SCC-1483 xenografts (p = 0.08). In vivo, immunohistochemistry demonstrated the ability of panitumumab to augment the antiproliferative and antiangiogenic effects of radiation. Conclusion: These studies have identified a favorable interaction in the combination of radiation and panitumumab in upper aerodigestive tract tumor models, both in vitro and in vivo. These data suggest that clinical investigations examining the combination of radiation and panitumumab in the treatment of epithelial tumors warrant

MOSFET dosimetry of the radiation therapy microbeams at the European synchrotron radiation facility

International Nuclear Information System (INIS)

Rozenfeld, A.; Lerch, M.

2002-01-01

Full text: We have developed an innovative on-line MOSFET readout system for use in the quality assurance of radiation treatment beams. Recently the system has found application in areas where excellent spatial resolution is also a requirement in the quality assurance process, for example IMRT, and microbeam radiation therapy. The excellent spatial resolution is achieved by using a quadruple RADFET TM chip in 'edge on' mode. In developing this approach we have found that the system can be utilised to determine any error in the beam profile measurements due to misalignment of RADFET with respect to the radiation beam or microbeam. Using this approach will ensure that the excellent spatial resolution of the RADFET used in 'edge-on' mode is fully utilised. In this work we report on dosimetry measurements performed at the microbeam radiation therapy beamline located at the European Synchrotron Radiation Facility. The synchrotron planar array microbeam with size 10-30 μm and pitch ∼200 μm has found an important application in microbeam radiation therapy (MRT) of brain tumours in infants for whom other kinds of radiotherapy are inadequate and/or unsafe. The radiation damage from an array of parallel microbeams correlates strongly with the range of peak-valley dose ratios (PVDR), ie, the range of the ratio of the absorbed dose to tissue directly in line with the mid-plane of the microbeam to that in the mid-plane between adjacent microbeams. Novel physical dosimetry of the microbeams using the online MOSFET reader system will be presented. Comparison of the experimental results with both GaF film measurements and Monte Carlo computer-simulated dosimetry are described here for selected points in the peak and valley regions of a microbeam-irradiated tissue phantom

The current state of radiation education in schools and results of the opinion survey on radiation

International Nuclear Information System (INIS)

Murai, Kenji

2013-01-01

In 2008, a new guideline about radioactivity was added to the government guidelines for teaching junior high school science. Since then people involved with school education have been trying to spread correct information about radioactivity. On the other hand, people's confusion in the aftermath of the Fukushima Daiichi Nuclear Power Plant accident has clearly shown that people do not know much about radioactivity. Considering the situation, the author conducted an investigation about the current state of radiation education and carried out an opinion survey about radioactivity among adults. The investigation about education showed the following: (1) the nature of radiation, such as its permeability, and its uses were described in the government-approved textbooks; (2) basic knowledge, such as what are radiation effects, were described comprehensively in the supplementary reading recommendations made by the Ministry of Education, Culture, Sports, Science, and Technology; and (3) locale education committees created teaching materials such as guidance to present topics. The opinion survey had questions to judge: (1) current public understanding of radioactivity; (2) the degree of general information that people collected for themselves; (3) the degree of specific knowledge about radioactivity that people had; and (4) people's attitudes toward various problems with radioactivity in the environment. The results suggested that for radiation education the following items are important: (1) to learn that radioactivity exists in people's daily lives and is used safely in various field; (2) to get basic knowledge and better quantitative understanding of such things as radioactivity units, radiation dose and radiation effects; and (3) to acquire practical experience to use the information effectively. (author)

Bimodal cell death induced by high radiation doses in the radioresistant sf9 insect cell line

International Nuclear Information System (INIS)

Chandna, S.

2003-01-01

Full text: This study was conducted to investigate the mode(s) of cell death induced by high radiation doses in the highly radioresistant Sf9 insect ovarian cell line. Methods: Cells were exposed to γ-radiation doses 200Gy and 500Gy, harvested at various time intervals (6h-72h) following irradiation, and subjected to cell morphology assay, DNA agarose gel electrophoresis, single cell gel electrophoresis (SCGE; comet assay) and Annexin-V labeling for the detection of membrane phosphatidylserine externalization. Cell morphology was assessed in cells entrapped and fixed in agarose gel directly from the cell suspension, thus preventing the possible loss of fragments/ apoptotic bodies. Surviving fraction of Sf9 cells was 0.01 at 200Gy and 98%) undergoing extensive DNA fragmentation at 500Gy, whereas the frequency of cells with DNA fragmentation was considerably less (∼12%) at 200Gy. Conclusions: While the mode of cell death at 200Gy seems to be different from typical apoptosis, a dose of 500Gy induced bimodal cell death, with typical apoptotic as well as the atypical cell death observed at 200Gy

Radiation Control on Uzbekistan Borders - Results and Perspectives

International Nuclear Information System (INIS)

Petrenko, Vitaliy; Yuldashev, Bekhzod; Ismailov, Ulughbek; Shipilov, Nikolay; Chipizubov, Sergey; Avezov, Anvar

2009-01-01

The measures and actions on prevention, detection and response to criminal or unauthorized acts involving radioactive materials in Uzbekistan are presented. In frames of program of radiation monitoring to prevent illicit trafficking of nuclear and radioactive materials main customs border checkpoints were equipped with commercial radiation portal monitors. Special radiation monitors elaborated and manufactured in INP AS RU are installed in INP(main gates, research reactor and laboratory building) to provide nuclear security of Institute facilities. The experience of Uzbekistan in establishing radiation monitoring systems on its borders, their operation and maintenance would be useful for realization of proposed plan of strengthening measures to prevent illicit trafficking in Republics of Central Asia region.

Covariant electromagnetic field lines

Science.gov (United States)

Hadad, Y.; Cohen, E.; Kaminer, I.; Elitzur, A. C.

2017-08-01

Faraday introduced electric field lines as a powerful tool for understanding the electric force, and these field lines are still used today in classrooms and textbooks teaching the basics of electromagnetism within the electrostatic limit. However, despite attempts at generalizing this concept beyond the electrostatic limit, such a fully relativistic field line theory still appears to be missing. In this work, we propose such a theory and define covariant electromagnetic field lines that naturally extend electric field lines to relativistic systems and general electromagnetic fields. We derive a closed-form formula for the field lines curvature in the vicinity of a charge, and show that it is related to the world line of the charge. This demonstrates how the kinematics of a charge can be derived from the geometry of the electromagnetic field lines. Such a theory may also provide new tools in modeling and analyzing electromagnetic phenomena, and may entail new insights regarding long-standing problems such as radiation-reaction and self-force. In particular, the electromagnetic field lines curvature has the attractive property of being non-singular everywhere, thus eliminating all self-field singularities without using renormalization techniques.