bluuebunny/crossref_metadata_2025 huggingface dataset:
American Geophysical Union, Wiley Renew Publishing Partnership
Authors: McEntee Chris
Published: February 2017

The scientific society's journals have made major gains in frequency of citation and speed of publication since the partnership began in 2013.
Diffuse Optical Spectroscopy and Imaging to Detect and Quantify Adipose Tissue Browning
Authors: Dinish U. S , Wong Chi Lok , Sriram Sandhya , Ong Wee Kiat , Balasundaram Ghayathri , Sugii Shigeki , Olivo Malini
Published: February 2017

Adipose (fat) tissue is a complex metabolic organ that is highly active and essential. In contrast to white adipose tissue (WAT), brown adipose tissue (BAT) is deemed metabolically beneficial because of its ability to burn calories through heat production. The conversion of WAT-resident adipocytes to “beige” or “brown-like” adipocytes has recently attracted attention. However, it typically takes a few days to analyze and confirm this browning of WAT through conventional molecular, biochemical, or histological methods. Moreover, accurate quantification of the overall browning process is not possible by any of these methods. In this context, we report the novel application of diffuse reflectance spectroscopy (DRS) and multispectral imaging (MSI) to detect and quantify the browning process in mice. We successfully demonstrated the time-dependent increase in browning of WAT, following its induction through β-adrenergic agonist injections. The results from these optical techniques were confirmed with those of standard molecular and biochemical assays, which measure gene and protein expression levels of UCP1 and PGC-1α, as well as with histological examinations. We envision that the reported optical methods can be developed into a fast, real time, cost effective and easy to implement imaging approach for quantification of the browning process in adipose tissue.
Clomipramine causes osteoporosis by promoting osteoclastogenesis via E3 ligase Itch, which is prevented by Zoledronic acid
Authors: Li Xing , Sun Wen , Li Jinbo , Wang Mengmeng , Zhang Hengwei , Pei Lingpeng , Boyce Brendan F. , Wang Zhiyu , Xing Lianping
Published: February 2017

Patients taking antidepressants, including Clomipramine (CLP), have an increased risk of osteoporotic fracture. However, the effects of CLP on bone metabolism are unknown. Here, we demonstrate that WT mice treated with CLP for 2 weeks had significantly reduced trabecular bone volume and cortical bone thickness, associated with increased osteoclast (OC) numbers, but had no change in osteoblast numbers or bone formation rate. Bone marrow cells from CLP-treated mice had normal OC precursor frequency, but formed significantly more OCs when they were cultured with RANKL and M-CSF. CLP promoted OC formation and bone resorption and expression of OC-associated genes. CLP-induced bone loss was prevented by Zoledronic acid. At the molecular level, CLP inhibited the activity of the ubiquitin E3 ligase Itch. CLP did not promote OC formation from bone marrow cells of Itch−/− mice in vitro nor induce bone loss in Itch−/− mice. Our findings indicate that CLP causes bone loss by enhancing Itch-mediated osteoclastogenesis, which was prevented by Zoledronic acid. Thus, anti-resorptive therapy could be used to prevent bone loss in patients taking antidepressants, such as CLP.
Wafer scale millimeter-wave integrated circuits based on epitaxial graphene in high data rate communication
Authors: Habibpour Omid , He Zhongxia Simon , Strupinski Wlodek , Rorsman Niklas , Zirath Herbert
Published: February 2017

In recent years, the demand for high data rate wireless communications has increased dramatically, which requires larger bandwidth to sustain multi-user accessibility and quality of services. This can be achieved at millimeter wave frequencies. Graphene is a promising material for the development of millimeter-wave electronics because of its outstanding electron transport properties. Up to now, due to the lack of high quality material and process technology, the operating frequency of demonstrated circuits has been far below the potential of graphene. Here, we present monolithic integrated circuits based on epitaxial graphene operating at unprecedented high frequencies (80–100 GHz). The demonstrated circuits are capable of encoding/decoding of multi-gigabit-per-second information into/from the amplitude or phase of the carrier signal. The developed fabrication process is scalable to large wafer sizes.
Is a person-affecting solution to the nonidentity problem impossible? Axiology, accessibility and additional people
Authors: Roberts Melinda A.
Published: February 2017

This paper considers two objections based in axiological considerations against the position that whether a given outcome, or possible future or world, is morally worse than a second world may depend in part on what is going on at a third world. Such a wide-angled approach to determining worseness is critical to the solution I have previously proposed in connection with the nonidentity problem. I argue that both objections fail.
Survey of metallo-β-lactamase-producing Enterobacteriaceae colonizing patients in European ICUs and rehabilitation units, 2008–11
Authors: Papagiannitsis C. C. , Izdebski R. , Baraniak A. , Fiett J. , Herda M. , Hrabák J. , Derde L. P. G. , Bonten M. J. M. , Carmeli Y. , Goossens H. , Hryniewicz W. , Brun-Buisson C. , Gniadkowski M. ,   on behalf of the MOSAR WP2, WP3 and WP5 study groups, Grabowska A. , Nikonorow E. , Dautzenberg M. J. , Adler A. , Kazma M. , Navon-Venezia S. , Malhotra-Kumar S. , Lammens C. , Legrand P. , Annane D. , Chalfine A. , Giamarellou H. , Petrikkos G. L. , Nardi G. , Balode A. , Dumpis U. , Stammet P. , Arag I. , Esteves F. , Muzlovic I. , Tomic V. , Mart A. Torres , Lawrence C. , Salomon J. , Paul M. , Lerman Y. , Rossini A. , Salvia A. , Samso J. Vidal , Fierro J.
Published: February 2017

Objectives

The objective of this study was to perform a multinational survey of patients' colonization by metallo-β-lactamase (MBL)-producing Enterobacteriaceae, including their molecular characterization.

Methods

Patients in 18 hospital units across Europe and Israel (n = 17 945) were screened between mid-2008 and mid-2011. MBL-producing isolates were typed by PFGE and MLST. MBL genes were amplified and sequenced within their integrons. Plasmids with MBL genes were analysed by nuclease S1 plus hybridization profiling, mating and transformation assays, and by PCR-based replicon typing.

Results

Ninety-one patients in nine centres (six countries), including 62 patients in two Greek ICUs, carried 94 non-duplicate MBL-producing organisms. Klebsiella pneumoniae isolates from Greece dominated (n = 57) and belonged mainly to ST147, ST36 and ST383. All but one of the isolates expressed VIM-1-type MBLs. Isolates of Greek origins produced five enzymes, including new VIM-39, encoded by class 1 integrons of four types. In-e541-like elements prevailed, comprising six variants located on IncR, IncFIIK, IncR + FIIK, IncR + A/C or non-typeable plasmids. The other group were new In4873 and In4863, being the first In416-like elements identified in Greece, which were present on IncA/C or non-typeable plasmids. Isolates from other countries produced only VIM-1 and the major integron was In916, identified in 16 organisms from France, Italy and Spain. In916 was carried by four plasmid types, including IncA/C, IncFIIK and IncHI2. Other integrons included a new element, In3103, in Spain and In110 identified only in Latvia.

Conclusions

This study provided fully comparable data on the occurrence and molecular characteristics of VIM-producing Enterobacteriaceae in a group of hospital units across Europe, documenting recent changes in their epidemiology.
Galactic interstellar filaments as probed by LOFAR and Planck
Authors: Zaroubi S. , Jelić V. , de Bruyn A. G. , Boulanger F. , Bracco A. , Kooistra R. , Alves M. I. R. , Brentjens M. A. , Ferrière K. , Ghosh T. , Koopmans L. V. E. , Levrier F. , Miville-Deschênes M.-A. , Montier L. , Pandey V. N. , Soler J. D.
Published: February 2017

Recent Low-Frequency Array (LOFAR) observations at 115–175 MHz of a field at medium Galactic latitudes (centred at the bright quasar 3C196) have shown striking filamentary structures in polarization that extend over more than 4° across the sky. In addition, the Planck satellite has released full sky maps of the dust emission in polarization at 353 GHz. The LOFAR data resolve Faraday structures along the line of sight, whereas the Planck dust polarization maps probe the orientation of the sky projected magnetic field component. Hence, no apparent correlation between the two is expected. Here we report a surprising, yet clear, correlation between the filamentary structures, detected with LOFAR, and the magnetic field orientation, probed by the Planck satellite. This finding points to a common, yet unclear, physical origin of the two measurements in this specific area in the sky. A number of follow-up multifrequency studies are proposed to shed light on this unexpected finding.
Rheumatoid Arthritis of the Temporomandibular Joint
Authors: CHALMERS I. M. , BLAIR G. S.
Published: February 2017

In a detailed study of 100 consecutive cases of rheumatoid arthritis, clinical abnormalities were present in the temporomandibular joints in 71.0 per cent of patients compared with 41.1 per cent of a group of matched controls. This difference is highly significant (P < 0.0005). Circular tomography was used to study the joints radiologically. By this technique, which does not appear to have been used previously in a study of this nature, 78.7 per cent of the rheumatoid patients' joints showed abnormalities compared with 33.9 per cent of the control joints. This difference is also highly significant (P < 0.0005). Certain clinical and radiological features appeared to be almost specific for rheumatoid arthritis and to correlate with increasing severity of the disease. Rheumatoid arthritis appears to affect the temporomandibular joint more commonly than was at one time thought.
Application of Thermoluminescence Dosemeters for Personnel Monitoring in India
Authors: Lakshmanan A.R. , Chandra B. , Pradhan A.S. , Supe S.J.
Published: February 2017

In 1975 CaSO4:Dy Teflon dosemeters were introduced for countrywide beta and gamma personnel monitoring. One third of the radiation workers are now being monitored with TLDs. This paper discusses some characteristics of this personnel monitoring system.
Skin Dose Determination with the TSEE of BeO Thin Film Detectors
Authors: Kriegseis W. , Petel M. , Portal G. , Scharmann A. , Wieters C.U.
Published: February 2017

Exoelectron emitting BeO thin film detectors were covered with polycarbonate foils of different thicknesses from 1.9-19.2 mg.cm-2 and exposed to 147Pm, 204Tl and 90Sr-90Y beta sources. Even for low energy beta rays from 147Pm the dependence of their dose response on foil thickness corresponded to the depth dose in soft tissue.
Porcelain Slices as a Stable Thermoluminescence Dosemeter up to 500 oC
Authors: Stoneham D. , Green T.H. , Voice E.
Published: February 2017

Porcelain slices have been used as a dosemeter to measure low gamma doses at 300 oC in the Prototype Fast Reactor at Dounreay. At the 1980 Toulouse Conference Aitken, Bussel and Voice reported the use of the 430 oC peak of natural fluorite to measure the gamma flux at 250 oC and comparisons were first made against this technique. By using porcelain slices cut into sections 7 mm square and 200 µm thick and encapsulated in aluminium, it is possible to measure the gamma flux up to a temperature of 500 oC. The sensitivity changes induced in the 100 oC peak (the so-called pre-dose effect) enable minimum dose evaluations to 10 mGy ± 10% to be made. This sensitivity change is activated by post-irradiation heating to 600 oC; at 300 oC only 4% of this change has been activated, but at 500 oC, 25% change is observed. This limits the temperatures at which exposure can be made although higher temperatures are possible if lower accuracy is acceptable. There is no detectable loss due to thermal fading. Allowance is made for irradiation at elevated temperature by laboratory tests using a 60Co source. An added advantage with this technique is that after suitable thermal treatment, the slices can be re-used.
Thermoluminescence in Sintered CaB4O7:Dy and CaB4O7:Eu
Authors: Fukuda Y. , Mizuguchi K. , Takeuchi N.
Published: February 2017

TL in sintered CaB4O7 doped with activators, such as Eu, Dy and also Pb and Cu, has been investigated. For a heating rate of 20 oC.min-1, the TL glow peaks can be roughly grouped into three temperature regions: (I) 75~110 oC, (II) 170~190 oC, and (III) 255~275 oC. Their emission spectra depend on the activator and its valence. The activators release to the luminescence in the following way: Eu2+ to 440 nm, Dy3+ to 480 and 580 nm, Pb2+ to 275 nm, and Cu+ to 540 nm, respectively. Thermally stimulated current (TSC) was observed corresponding to all the temperatures at which TL glow peaks were observed. This indicates that the thermally released charge carriers recombine with the luminescent centres through conduction or/and valence bands, and not by a tunnelling process. All the TL glow peaks showed no supralinearity before they saturated at an exposure of about 2.58 C.kg-1 (104 R). Peaks appearing at the temperature regions II and III retained memories of irradiation for a storage period of 6 months in the dark at room temperature.
The Determination of Gamma Doses due to Capture and Inelastic Scattering Processes in a Trunk Phantom Irradiated with 15 MeV Neutrons
Authors: Reulein W. , Kühn H.
Published: February 2017

The aim of these investigations was to improve gamma dose determination with Geiger-Müller counters. The required values of the responses of the detector for neutrons and gamma rays were taken from the literature. The time discrimination of the signals, a method used to discriminate neutron and gamma radiation in neutron response measurements, makes possible the determination of the gamma doses caused by (n,n'?) processes. The experiments were performed with an accelerator in pulse mode. The radiation time was selected to be as small as possible to reduce the build-up of thermal neutrons in the phantom during irradiation. The pause time was chosen to allow the decrease of thermal neutrons produced after moderation. The different gamma spectra emitted by (n,n'?) and (n,?) processes were considered in calculating the gamma dose. In the centre of the trunk of the water phantom, the H?(n,n'?)/H?(n,?) ratio is given by 2.0 ± 0.2.
A Facility to Produce Collimated Neutron Beams at the Legnaro Laboratories
Authors: Colautti P. , Talpo G. , Tornielli G.
Published: February 2017

The 7 MV Van de Graaff and the 16 MV Tandem accelerators at the Legnaro National Laboratories can be used to produce fast neutron fluxes of moderate intensity, ranging in energy from 1 MeV to 50 MeV. A W-polyethylene-Pb cylindrical collimator has been constructed in order to produce a collimated neutron beam, with well defined dose and microdose characteristics for radiobiological experiments. The collimator can be assembled in different configurations allowing both for different thicknesses and different beam apertures. Dosimetric measurements have been made with a d(4.5)+Be source. These demonstrate sharp beam edges with attenuation behind the shield of 20% with the 15 cm collimator and 1.5% with the 50 cm collimator.
Patient Dosimetry and Staff Protection at the Clatterbridge High Energy Neutron Facility
Authors: Blake S.W. , Finch J. , Bonnett D.E. , Shaw J.E.
Published: February 2017

The Clatterbridge High Energy Neutron Facility was designed to provide a neutron beam comparable to an X ray beam generated by a modern linear accelerator in terms of both dose distribution and patient positioning. This has been achieved using a cyclotron which accelerates protons to 62 MeV, and an isocentric treatment unit incorporating a variable collimator. Neutrons are generated by the interaction of the proton beam with a beryllium target situated in the treatment head. The neutron beam is described in terms of the beam parameters measured for routine clinical use. Where relevant, they are compared with those of an 8 MV X ray beam. The neutron and X ray beams are also compared by means of treatment plans produced for the two beams. Finally, the dose equivalent to radiographic staff caused by the neutron activation of the treatment machine and room are presented and discussed. These are found to be comparable with that measured at other facilities employing neutron beams with similar energies.
Neutron Physics Studies Relating to Cancer Therapy on the Clatterbridge Cyclotron
Authors: Crout N.M.J. , Fletcher J.G. , Scott M.C. , Taylor G.C.
Published: February 2017

Both neutron spectrum and microdosimetric measurements have been made in a water phantom exposed to different field size therapy beams from the 62 MeV Clatterbridge cyclotron. The neutron spectrum measurements have been made using an NE213 detector and the procedures for measuring the response functions necessary for unfolding are described. The results of measurements both in air and in phantom are presented. The spectrum measurements show very significant in-beam hardening with depth into the phantom, and the microdosimetric measurements are consistent with this finding.
Thermoluminescent LiF:Cu,Mg,P for Gamma Ray Dosimetry in Mixed Fast Neutron-Gamma Radiation Fields
Authors: Horowitz Y.S. , Shachar B.B.
Published: February 2017

In thermoluminescent dosimetry (TLD), the relative TL response, ?n?, of fast neutrons to gamma rays usually lies betwen 0.05 to 0.3. Recently, several groups have reported on the development of a new TL material, LiF:Cu,Mg,P, with a gamma ray TL sensitivity ~20 times greater than LiF:Mg,Ti (TLD-100, Harshaw-Filtrol). We have measured the relative TL response of LiF:Cu,Mg,P to 252Cf fast neutrons (E = 2.5 MeV). Neutron dosimetry was carried out using the polycarbonate technique, and, for comparison purposes, the neutron irradiations were also carried out simultaneously on pairs of LiF:Mg,Ti (TLD-700, H/F) and CaF:Tm (TLD-300, H/F) dosemeters. The following results were obtained; (1) ?(LiF:Cu,Mg,P) = 0.011 ± 0.01; (2) ?(TLD-700)/?(LiF:Cu,Mg,P) ( 5:1; and, (3) ?(TLD-300)/?(LiF:Cu,Mg,P) ( 4:1. Estimation of the TL signal was carried out using cmputerised glow curve deconvolution (CGCD). These results establish LiF:Cu,Mg,P as the 'tissue-equivalent' TL material least sensitive to fast neutrons discovered to date and suggest that LiF:Cu,Mg,P can serve as an excellent discriminator for gamma ray dose measurement in fast neutron - gamma ray radiation fields.
Dispersion of 226Ra in a Contaminated Environment
Authors: de Bettencourt A.O. , Texeira M.M.G.R. , Madruga M.J. , Faisca (INVITED) M.C.
Published: February 2017

A radium salts extraction factory was established in Portugal in 1908 in the northeastern part of the country. It was abandoned in the forties and is now in ruins. Wastes (mainly sands) highly contaminated with 226Ra were left near these ruins. Measurements were performed to evaluate the extent of the contamination due to the dispersion of radium around this site, using portable Gieger tube equipment as well as by gamma spectrometry analyses of soil samples. Vertical profiles of soil were taken to a depth of about 40 cm, and 5 cm sections were analysed by gamma spectrometry to evaluate the vertical distribution of 226Ra and 210Pb. Some soil characteristics, such as pH, organic matter and exchangeable calcium and radium were also analysed. The dispersion of radium seems to be mostly due to the removal of contaminated wastes by mechanical means, although some leaching may have occurred. Laboratory experiments were also conducted on sandy and agricultural soils to study the leaching of 226Ra and 210Pb with rainwater and to help explain the results obtained in the field study. The observed influence of different parameters on this leaching are briefly discussed. Vegetables grown on these soils (mainly cabbage) were analysed for their content of 226Ra and 210Pb in order to calculate concentration factors. For 226Ra, these range from about 7 x 10-3 to 7 x 10-2. For 210Pb, they range from about 10-3 to 2 x 10-2.
Investigations of the Properties of an Instrument for In Situ Exhalation Measurements
Authors: Aldenkamp F.J. , Put L.W. , de Meijer R.J.
Published: February 2017

Experimental investigations on the properties of an instrument for in situ measurements of the radon exhalation rate revealed several unexpected results. The measurements were based on determining the growth of the activity in a measuring volume. Exhalation rates are often determined from the initial linear increase of the activity; this investigation, however, indicates that such a determination may not be reliable in the case of porous materials like gypsum and soil. The investigations also revealed that the results depend on a number of parameters such as temperature and aerosol conditions.
Environmental Radiation Survey Around a Coal-Fired Power Plant Site
Authors: Battaglia A. , Bramati L.
Published: February 2017

For siting of a coal-fired power station in the Apulia region, ENEL (Ente Nazionale Energia Elettrica) carried out an environmental impact evaluation. Owing to the natural radioactivity in the coal and in the ash, the local authorities required an investigation of the environmental radioactivity in the area. Measurements on the radiation level, of radioactivity concentrations in soil and of radon concentration in the air were carried out at selected points on the basis of the expected atmospheric diffusion and ash disposal. At some points higher than normal radiation levels and some disequilibrium in the natural uranium decay products were observed due to hydrogeological events in the soils near the coast. A comparison is made of the radiological impact by the power plant operation and the impact due to the natural radiation environment.
Preliminary Measurements of Indoor Radon in Ljubljana, Yugoslavia
Authors: Kobal I. , Vavpotic J. , Burger J. , Stegnar P.
Published: February 2017

In Ljubljana, the capital of Slovenia, one of six Yugoslav republics, 28 houses were selected according to their size, age and construction material, as sampling points to measure indoor air 222Rn concentrations. Air samples were taken every three months and analysed for 222Rn. Radon was isolated from air contained in a 1.2 dm3 sampling glass ampoule, transferred to a scintillation cell and counted. In some homes radon was measured under different microclimatic conditions. In addition outdoor air was surveyed in winter during a temperature inversion when increased radon concentration is expected in a mass of stagnant polluted air. The results obtained have not been quantitatively elaborated. They merely show a preliminary picture of indoor radon levels in Ljubljana and as such are a good base for a planned nationwide radon monitoring programme.
Sources of Technologically Enhanced Natural Radioactivity and Their Impact in Slovenia (Yugoslavia)
Authors: Brajnik D. , Krizman M. , Kobal I. , Stegnar P.
Published: February 2017

The environmental impact of a uranium mine and several other sources of technologically enhanced natural ratioactivity such as coal fired power plants, coal mines, production of phosphoric acid, phosphate fertilisers and titanium dioxide contributing to the radioactive pollution in Slovenia has been studied. The main contribution to the individual dose is caused by inhalation of radon and its daughters in the vicinity of the uranium mine. Other sources contribute mainly to the radioactive pollution of the river Sava and its underground water.
Modelling of the Electron and Ion Kinetics in Cylindrical Proportional Counters
Authors: Ségur P. , Pérès I. , Boeuf J.P. , Barthe (INVITED) J.
Published: February 2017

This paper gives an overview of the state of the art in the modelling of electron and ion kinetics in proportional counters. Three specific points are emphasised. First, we determine, by using an accurate solution of the Boltzmann equation, the electron transport parameters (ionisation coefficient, drift velocity, diffusion coefficient) in methane over a very large range of values of the ratio electric field upon pressure. We then calculate the gas gain of the counter by using our calculated data. The calculation of this gas gain is generally based on the assumption that the ionisation coefficient and other transport paraments, at a given location in space, depend only on the value of the local electric field (equilibrium assumption). In a proportional counter, the electric field can present large spatial variations over distances of the order of one or a few electron mean free paths (especially for low gas pressure) and the equilibrium assumption can become questionable. The second objective of this work is to investigate the importance of these non-equibibrium effects. The existence of space charge fields in the counter can greatly affect its gain. In order to estimate the magnitude of these effects, self-consistent calculations based on a macroscopic description (continuity and momentum transfer equations) of the electron and ion kinetics coupled with Poisson equation are carried out. We show how such calculations make possible the determination of the onset and the importance of space charge effects in the counter.
Quality Factor, Concepts and Issues
Authors: Sinclair (INVITED) W.K.
Published: February 2017

Three issues in quality factor assignment arise from Report 40 of the ICRU. These include the validity of the observation of high RBE values for high-LET radiation at low doses, the question of reference radiation, X or ? rays, and the 'effective' quality factor in the body compared with the nominal value of Q. On the first item, high values of RBE at low doses are becoming generally accepted, see a recent report from the NCRP. On the second, a survey of past recommendations of both ICRP and NCRP indicate that both organisations have, for protection purposes, always set all low-LET radiations equal to 1 and accepted the differences (of 2-3 times) between them. However, for radiobiological purposes high energy ? rays are to be preferred as the reference radiation. Third, the 'effective quality factor' or radiation weighting factor, WR, for a variety of whole body exposure circumstances can be estimated from HE = WR S wTDT where the effective dose equivalent is the summation of tissue weighting factors wT, times the absorbed dose DT for the organ, multiplied by an average 'radiation weighting factor' WR. WR values can be calculated for a variety of exposure circumstances and are always less than Q. Maximum values, for fission neutrons for example, are not greatly less however. These issues are under further consideration by the ICRP.
The Effect of Dynamic Disordering Upon Thermostimulated Processes in TLD Ionic Crystals
Authors: Tale I. , Tale V. , Nagornyi A.
Published: February 2017

Annealing of radiation defects has been studied by means of the fractional glow technique in KC1-Tl and CaF2 crystals in the temperature range where the ionic motion arises. A novel model of dynamic disordering for describing the kinetics of thermostimulated luminescence is proposed, taking into account the fluctuational changes of the trap spatial structure and their energetics during the relaxation process due to the interaction with mobile ions and/or vacancies.
Neutron Dosimetry with SSNTDs and Spark Counting Evaluation
Authors: Schmidt W.F.O.
Published: February 2017

A new system consisting of polypropylene spheres 25 cm in diameter and SSNTDs as central detectors is presented. The behaviour of these spheres for different neutron spectra is well known. The SSNTD foil in use is Makrofol KG (0.01 mm, Bayer). Two platelets of natural uranium (U(nat) 16x13 mm2 in size (thickness 0.25 mm) serve as radiators in contact with the foil, which is fixed in a commercial dia-frame (inner dimensions 36x24 mm2). The foils are etched in KOH (28%, 60 oC, 2 h) and evaluated with a spark counter. The system is cheap, robust, insensitive to water and shocks and does not depend on electrical supply. Readings are completely insensitive to accompanying photons. Doses may be measured from 0.01 mSv to 1000 Sv. The system is designed for area neutron survey at various neutron facilities up to energies of 14 MeV.
Simultaneous Measurement of Angle of Incidence and Energy in Fast Neutron Fields by CR-39
Authors: Guldbakke S. , Pitt E. , Scharmann A. , Simmer R.
Published: February 2017

Commercial American Acrylics CR-39 (dosimetry grade), partly covered with polypropylene radiators of increasing thickness (step radiator) has been irradiated with monoenergetic neutrons (0.565 - 5 MeV) in parallel beams at various angles of incidence. The step rise has been varied with neutron energy, the maximum thickness of the step-radiator exceeding the maximum recoil proton energy range. The CR-39 detectors have been etched electrochemically and evaluated by a semi-automatic image analysing system (Leitz Autoscope P). By varying the radiator thickness the track density increases up to a saturation track density. The ratio of saturation track density of uncovered CR-39 depends on the angle of incidence. The knowledge of the saturation radiator thickness combined with the angle of incidence allows, on the other hand, the neutron energy to be estimated.
Beta Dosimetry Using Thin TL Detectors
Authors: Fellinger J. , Schmidt P. , Hübner K.
Published: February 2017

A personnel dosemeter for routine dosimetry in mixed beta-gamma fields requires a thin, nearly tissue-equivalent detector with a high sensitivity and with a high mechanical resistance. A special TL sandwich detector has been designed for application in beta dosimetry. It consists of two TL sensitive layers (TLD 1 and TLD 2) separated by a material with poor thermal conductivity. In consequence of the poor thermal conductivity of the separating layer the temperatures of TLD 1 and TLD 2 are different during the evaluation process. The TLD 1 layer shows an excellent beta sensitivity (about 75% for 14C beta rays related to 90Sr/90Y). Information about the radiation field can be obtained by using the relation of the detector readings of TLD 1 and TLD 2. The production of the TL sandwich detector is described, and the dosimetric properties in different beta fields are represented and discussed.
Individual Dosimetry Using Electret Detectors
Authors: Dörschel B. , Prokert K. , Seifert H. , Stoldt C.
Published: February 2017

Electret dosemeters are designed as small air-filled ionisation chambers in which one of the electrodes is replaced by an electret. The dosemeter readout expressed as the difference in the electret voltage measured before and after the irradiation is proportional to the absorbed dose in the chamber gas. The application of such electret detectors to individual dosimetry requires knowledge of their energy and angular dependence as well as of their dynamic range and measurement accuracy. The dosimetric properties of electret ionisation chambers containing corona-charged PTFE electrets are described. Conclusions about their applicability in individual dosimetry in photon fields are drawn.
A TL Technique for On-Plate Measurement of Doses Below 1 Microgray
Authors: Benkö L.
Published: February 2017

The TL response of CaSO4:Dy to extremely low beta doses delivered by samples of environmental origin was investigated. Taking into account the main factors limiting the precision of measurements below about 5 µGy, a special TL technique was developed. The heating chamber and the PM assembly are placed in a 20 cm thick iron shield. 0.1 g of CaSO4:Dy is spread on the heating plate, constituting a 1.5 cm diam. phosphor layer. The phosphor, heated to 350 oC, can be re-used with no change in sensitivity at low doses. Replacing the PM tube with a container filled with 4 g of sample (soil, pottery clay) or CaSO4:Dy (for background correction), on-plate exposures are made overnight. For calibrations and quick checks, K2CO3 and NBL reference standards with specified U and Th content are used. This technique enables highly reliable measurements to be performed at doses as low as 0.1 µGy. Some of the results relating to isotope dependence, build-up of spurious TL and possible applications in TL dating are also presented.
Accident Dosimetry Using Environmental Materials Collected from Regions Downwind of Chernobyl: A Preliminary Evaluation
Authors: Hütt G. , Brodski L. , Bailiff I.K. , Göksu Y. , Haskell E. , Jungner H. , Stoneham D.
Published: February 2017

Environmental materials including bricks, tiles porcelain fixtures and a variety of other ceramic objects were collected in July, 1990, and August, 1991, from indoor and outdoor locations in the town of Pripyat, situated 3 km NW of the Chernobyl nuclear power plant. The samples were distributed to a number of laboratories to investigate their suitability for thermoluminescence dosimetry and for measurement of gamma ray doses with samples deemed suitable, using pre-dose, fine-grain and quartz inclusion thermoluminescence techniques. In the most heavily exposed region of Pripyat, values ranged from near background (" 0.1 Gy) in the most shielded interior locations of apartment buildings to a maximum of 0.6 Gy directly behind closed windows, while exterior values ranged from 1.7 to 2.3 Gy for samples located at least 1 m above ground level.
Eight Years Application of Computerised Glow Curve Analysis at the Rossendorf Nuclear Research Centre
Authors: Sahre P. , Schönmuth Th.
Published: February 2017

Since 1983 computerised glow curve analysis has been carried out at the Rossendorf Nuclear Research Centre. The application fields, the methods developed and the results obtained are: (1) Skin dose determination in beta/gamma fields. The glow curve of a fast, directionally heated thick TL detector is deconvoluted into contributions of standard glow curves for beta and gamma irradiation of known depth dose distribution. Doses in tissue depths from 0.05 mm to 1.6 mm are obtainable. (2) Fading reduction. The evaluation of only the separated main peak yields the fading-independent dose and, additionally, the evaluation of the separated low temperature peak gives an indication of the time elapsed since a single high exposure. (3) High range exposure. For exposures of CaSO4:Dy detectors to doses from 0.1 kGy to 5 kGy the saturation effects can be reduced by deconvolution of the glow curve into up to five Gaussian peaks. The dose is obtained from two or more peak areas as well as from the ratio of peak height and location.
Methods for the Rapid Deconvolution of Thermoluminescence Glow Curves
Authors: Lowry K.A. , Lee Y. , Gorbics S.G. , Johnson T.L.
Published: February 2017

Methods for the rapid deconvolution of thermoluminescence glow curves are described. By tailoring a least squares fitting routine specifically for glow curve deconvolution, we have achieved an order of magnitude reduction in unfolding time. For routine applications, where many similar glow curves are analysed, another order of magnitude reduction is achieved by fitting the glow curves to a previously determined set of glow peaks, rather than deconvoluting each curve into a unique set of glow peaks. For this case, a glow curve consisting of 200 data points can be deconvoluted into 12 glow peaks in less than 0.2 s.
The Determination of Radiation Dose by Mail for Diagnostic Radiological Examinations with Thermoluminescent Dosemeters
Authors: DeWerd L.A. , Chiu N.B.
Published: February 2017

The measurement of radiation exposure using thermoluminescence dosemeters by mail is described. Measurement results of entrance skin exposure on mammography patients and measurement of exposure and beam profile for computerised tomography examination are presented in detail. The mammography results show that the entrance exposure is greatly dependent on breast composition and compression thickness. The usefulness of the computerised tomography beam profile is also demonstrated.
Properties of Threshold Detectors for Testing Neutron Dosimetry Calibrations
Authors: Balcázar M. , Tavera L. , Camacho M.E. , Alonso G.
Published: February 2017

A neutron detector combination based on solid state nuclear track detectors, which makes use of uranium oxide and LiF converters together with cadmium plastic absorbers was calibrated in a known neutron field of a heavy water moderated 252Cf source. From the derived equations describing the spectrometer characteristics it is possible to measure the average 235U neutron fission cross section s5 in the energy interval from 10 to 104 eV where there are more than 50 resonances. s5 was obtained from fission track densities in two Makrofol detectors, a bare one and one with cadmium shielding. The experimental s5 values of 5.7 and 20.5 b agree with the calculated values of 1.3 to 22 b obtained from a nuclear data code. The reported average cross section values cannot be considered as new nuclear data, but the utility is shown of using them for data analyses.
Further Developments of a Model for Describing the Optical Bleaching of Thermoluminescence from Quartz as Applied to Sediment Dating
Authors: Morris M.F. , McKeever S.W.S.
Published: February 2017

The model by McKeever to simulate 'hard-to-bleach' thermoluminescence (TL) peaks is studied. The sensitivity of the model to its parameters is examined, and a wide variety of behaviour is found. The sensitivity of the TL signal and the size of the residual TL level for different sets of parameters are studied. It is observed that the TL sensitivity changes after bleaching and the residual level reached after long bleaching times depends upon the initial radiation dose.
Determination of Restricted LET Distribution for Mixed (n,gamma) Radiation Fields by High Pressure Ionisation Chamber
Authors: Golnik N. , Zielczynski M.
Published: February 2017

A novel method is presented for the determination of the energy loss distribution in the nanometric region from the initial recombination of ions in high pressure ionisation chambers. Low resolution distributions can be obtained by comparison of saturation curves for mixed and reference gamma radiations. The method was tested using two different ionisation chambers in field of 241Am-Be, 238Pu-Be and 252Cf neutron sources. Both the gamma component of the absorbed dose and the quality factor calculated from the obtained energy loss distributions agree with the values measured by other methods.
Inactivation Induced by Deuterons of Various LET in V79 Cells
Authors: Belli M. , Cera F. , Cherubini R. , Goodhead D.T. , Haque A.M.I. , Ianzini F. , Moschini G. , Nikjoo H. , Sapora O. , Simone G. , Stevens D.L. , Tabocchini M.A. , Tiveron P.
Published: February 2017

The results for inactivation of V79 cells irradiated by monoenergetic deuterons with LET of 18, 26 and 31 keV.µm-1 and their direct comparison with protons of comparable LET are presented. The experimental results show that at 31 keV.µm-1 cell inactivation is similar for protons and deuterons while, at lower LET, deuterons appear to be less lethal than protons. The use of parameters other than L(, such as L100 or Z2 eff/ß2, does not completely reconcile the differences in biological effectiveness among the particles pointing out their inadequacy for describing the radiation quality of light ions. The experimental results have been compared with the Monte Carlo track structure simulations, using the code MOCA 14, carried out for monoenergetic track segments of protons, deuterons and alpha particles of selected LET in the range 20-40 keV.µm-1. Existing track structure codes, and indeed essentially all other physical descriptions of radiations used to date, are unable to explain the observed differences in biological effectiveness between deuterons and protons.
An Approach to Experimental Microdosimetry at the Nanometre Scale
Authors: Pszona S. , Gajewski R.
Published: February 2017

An experimental set-up called 'Jet Counter' has been built for studying the microdosimetry pattern of the interactions of charged particles with nanometre-size gas volume. Such nanometre-size gas volume (in unit density scale) have been produced in a device consisting of a pulse operated valve which injects gas in the form of an expansion jet into an interaction chamber. The range of the effective thickness of the obtained simulated nanometre sites was from a tenth to 250 nm. The mean values of energies deposited in simulated sites of 11 and 36 nm, irradiated by 700 eV monoenergetic electrons, have been determined in the experiment.
Site-Specific Chromosome Damage and Myeloid Leukaemogenesis in the CBA Mouse
Authors: Silver A. , Bouffler S. , Finnon P. , Rance E. , Morris D. , Cox (INVITED) R.
Published: February 2017

Deletion and/or rearrangement of chromosome 2 is a very early and possibly initiating event for acute myeloid leukaemia in the CBA mouse. Here an outline is given of a series of cytogenetic and molecular studies which imply that the expression of radiation damage to this chromosome is highly non-random, being dependent upon the presence of specific telomere-like DNA repeat sequences at certain interstitial chromosomal locations. The secondary four-stranded DNA structures that may be formed at such telomeric chromosome sites and the potential role of these recombinogenic structures as preferential targets for radiation induced cytogenetic change are discussed.
An Integrated Model For Radiation Induced Cancer
Authors: Hall E.J. , Varma (INVITED) M.
Published: February 2017

Risk estimates for radiation induced cancer are based on epidemiological data, principally the Japanese A bomb survivors. These estimates for radiation are better known than for any other environmental pollutant, but they do not relate directly to exposure to low doses and low dose rates. Recent rapid advances in molecular genetics, coupled with steady gains in cellular biology, radiation physics and chemistry led to the notion that the time may not be far off when it may be possible to arrive at human cancer risk estimates entirely from laboratory data. Whether risk estimates based on laboratory data will ever replace estimates based on epidemiological studies is an open question. What is clear is that laboratory data can supplement the present risk estimates by providing information on the relative effectiveness of high LET radiations, the importance of dose rate and dose protraction, and by identifying subpopulations which are unusually sensitive or resistant to radiation carcinogenesis.
Influence of Shallow Mine-Workings on the Radon Concentrations in Houses: A Problem of Old Mining Regions
Authors: Lehmann R. , Czarwinski R.
Published: February 2017

In some regions of the German New Federal Lands, residues from early mining characterise the radiological situation and can also influence the radon concentration in buildings. Construction on waste rock with increased radium concentration, the use of waste rock as building material and construction above shallow mine shafts and adits are important in this connection. In Saxony, for instance, one has to reckon with probably hundreds of buildings that may be influenced by radon from shallow mine workings. Very short-term changes of radon concentrations in buildings over several orders of magnitude was well as their close temporal correlation with the underground airflow clearly indicate influences from underground. In Schneeberg and Schlema, fluctuations of radon concentration in buildings of several 10,000 Bq.m-3 within one hour were observed. In Schneeberg, the old mine was ventilated artificially by installing a ventilator with an output volume of 500 m3min-1. Thus the radon concentration in buildings of the central city area has been reduced. In Schlema, the radon rich shafts of early mining are ventilated at present by the still active ventilation system of the suspended uranium ore mining. In 1992, during the first six months, 4.5 x 109 m3 of mine air with a radon activity of 6.3 x 1014Bq were extracted from the mine. If the mine ventilators are switched off, radon concentration in buildings over mine shaft increases sharply by two orders of magnitude.
Biological Dosimetry in Different Compartments of the Respiratory Tract after Inhalation of Radon and its Daughters
Authors: Bisson M. , Collier C.G. , Poncy J.L. , Taya A. , Morlier J.P. , Strong J. , Baker S. , Monchaux G. , Fritsch P.
Published: February 2017

The aim of this study was to develop new assays for local dosimetry in the different compartments of the rat lung after inhalation of radon and its daughters under different exposure conditions. Sensitivity of these assays was compared with assays described previously for tracheal epithelial cells (TEC) and pulmonary alveolar macrophages (PAM). The incidence of micronuclei in TEC or PAM after cell proliferation induced by in vivo acute ozone exposure appeared to be the most sensitive method if proliferating cells only are taken into account. Proliferating cells were identified by immuno-staining after labelling with 5-bromo-2'-deoxyuridine in vivo. This method can also be applied to bronchial and bronchiolar epithelial cells by using similar histochemical method. Thus, a new assay is proposed which could be used in the same animal to perform sensitive biological dosimetry from the trachea to the alveoli along the lung tracheo-bronchial tree.
Characterisation of Some Parameters Affecting the Radon Exposure of the Population
Authors: Bochicchio F. , Campos-Venuti G. , Felici F. , Grisanti A. , Grisanti G. , Kalita S. , Moroni G. , Nuccetelli C. , Risica S. , Tancredi F.
Published: February 2017

Few and sporadic measurements are so far available on the characteristics of indoor radon and thoron daughters in typical Mediterranean areas. For this reason, a pilot study is being carried out in Rome, to study the equilibrium factor F and the influence of ventilation rates in realistic domestic environments. Preliminary data show both a significant influence of ventilation on indoor Rn and Tn daughter concentration and a non-negligible contribution of Tn daughters to the annual effective dose of inhabitants.
Public Responses to Indoor Pollution from Radon
Authors: Lee T.R. , Macdonald (INVITED) S.
Published: February 2017

A study of public responses to radon in the South West of England has been carried out, following an extensive household measurement campaign. The aims were to establish (a) the proportions who have taken the various steps on the route to remediation, (b) the biographical, housing and attitudinal variables that appear to influence householders' decisions, and (c) the effectiveness of the pamphlets and other forms of communication. A postal survey (N=3210) was divided between measurees above the 'action level'; measurees below the 'action level'; and a proportion of non-measurees. To control for volunteer bias, a further survey (N=763) was carried out by interview in the home. Severe losses occur at the successive stages, particularly in reading the campaign leaflet and deciding to apply for measurement. Only 3-5% of those above the action level have carried out effective remediation. A number of suggestions are made for improving the remediation rate.
Analysis of TL Glow Curves in Differently Doped LiF:Mg, Ti
Authors: Vana N. , Ritzinger G.
Published: February 2017

A computerised curve-fitting method was developed to calculate the trapping parameters in LiF TLD-100 and LiF:Mg,Ti. After irradiation in a 60Co field and with X rays emitted at different voltages the TL process is best described by first-order kinetics. A dependence of the trapping parameters on both the concentration of Mg and Ti and photon energy was detected.
Discrimination Between Neutrons and Gamma Rays and Evaluation of Dose with a Position Sensitive Semiconductor Detector in a Mixed Field
Authors: Ohkuma J. , Kawanishi M.
Published: February 2017

The application of a surface barrier position sensitive detector (PSD) for discrimination between neutrons and gamma rays in a mixed field is investigated. A centre part of the sensitive area of PSD is covered with the n-p converter foil and the energy and position signals from the single detector are used for identification of neutrons and gamma rays. Output signals are fed to multichannel analysers and a computer, and dose rates are evaluated separately for neutrons and gamma rays, taking account of energy spectra and reaction efficiencies, by an unfolding calculation in real time.