Cumulative effects of low X-ray doses on some liver function and proteins of diagnostic technicians working in conventional X-rays

ABSTRACT We present X-ray observations of novae V2491 Cyg and KT Eri about 9 yr post-outburst of the dwarf nova and post-nova candidate EY Cyg, and of a VY Scl variable. The first three objects were observed with XMM–Newton, KT Eri also with the Chandra ACIS-S camera, V794 Aql with the Chandra ACIS-S camera and High Energy Transmission Gratings. The two recent novae, similar in outburst amplitude and light curve, appear very different at quiescence. Assuming half of the gravitational energy is irradiated in X-rays, V2491 Cyg is accreting at $\dot{m}=1.4\times 10^{-9}{\!-\!}10^{-8}\,{\rm M}_\odot \,{\rm yr}^{-1}$, while for KT Eri, $\dot{m}\lt 2\times 10^{-10}{\rm M}_\odot \,{\rm yr}$. V2491 Cyg shows signatures of a magnetized WD, specifically of an intermediate polar. A periodicity of 39 min, detected in outburst, was still measured and is likely due to WD rotation. EY Cyg is accreting at $\dot{m}\sim 1.8\times 10^{-11}{\rm M}_\odot \,{\rm yr}^{-1}$, one magnitude lower than KT Eri, consistently with its U Gem outburst behaviour and its quiescent UV flux. The X-rays are modulated with the orbital period, despite the system’s low inclination, probably due to the X-ray flux of the secondary. A period of 81 min is also detected, suggesting that it may also be an intermediate polar. V794 Aql had low X-ray luminosity during an optically high state, about the same level as in a recent optically low state. Thus, we find no clear correlation between optical and X-ray luminosity: the accretion rate seems unstable and variable. The very hard X-ray spectrum indicates a massive WD.

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CONTINUUM X RAYS IN HIGHLY CHARGED ION-ATOM COLLISIONS

International Journal of PIXE ◽

10.1142/s0129083596000478 ◽

1996 ◽

Vol 06 (03n04) ◽

pp. 441-445

Author(s):

K. KAWATSURA ◽

T. HASEGAWA ◽

N. TERAZAWA ◽

S. ARAI ◽

M. SATAKA ◽

...

Keyword(s):

Energy Region ◽

Heavy Ion ◽

X Rays ◽

X Ray ◽

Radiative Processes ◽

Gas Target ◽

Electron Bremsstrahlung ◽

Low X ◽

Atom Collision ◽

The Continuum

Continuous X rays produced by highly charged heavy ion-atom collisions have been studied experimentally. 2–5.5 MeV/u F, Si, S and Cl ions with zero or one electron were bombarded with a thin gas target of H 2 and He. Emitted X-ray spectra were measured by using a Si(Li) X-ray detector at 90°. The characteristic X rays and radiative electron capture X rays were observed clearly, which were superimposed on the continuum X rays. The continuum X rays can be well explained by two types of radiative processes: mainly quasi-free electron bremsstrahlung (QFEB), and partly atomic bremsstrahlung (AB). It should be noticed that QFEB is predominant at low X-ray energy region and AB at high X-ray energy region in highly charged heavy ion-atom collision process.

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HERA Phase I Limits on the Cosmic 21 cm Signal: Constraints on Astrophysics and Cosmology during the Epoch of Reionization

The Astrophysical Journal ◽

10.3847/1538-4357/ac2ffc ◽

2022 ◽

Vol 924 (2) ◽

pp. 51

Author(s):

Zara Abdurashidova ◽

James E. Aguirre ◽

Paul Alexander ◽

Zaki S. Ali ◽

Yanga Balfour ◽

...

Keyword(s):

Theoretical Models ◽

Hydrogen Gas ◽

X Rays ◽

X Ray ◽

Upper Limits ◽

Adiabatic Cooling ◽

Radio Background ◽

Early Galaxies ◽

First Galaxies ◽

Low X

Abstract Recently, the Hydrogen Epoch of Reionization Array (HERA) has produced the experiment’s first upper limits on the power spectrum of 21 cm fluctuations at z ∼ 8 and 10. Here, we use several independent theoretical models to infer constraints on the intergalactic medium (IGM) and galaxies during the epoch of reionization from these limits. We find that the IGM must have been heated above the adiabatic-cooling threshold by z ∼ 8, independent of uncertainties about IGM ionization and the radio background. Combining HERA limits with complementary observations constrains the spin temperature of the z ∼ 8 neutral IGM to 27 K 〈 T ¯ S 〉 630 K (2.3 K 〈 T ¯ S 〉 640 K) at 68% (95%) confidence. They therefore also place a lower bound on X-ray heating, a previously unconstrained aspects of early galaxies. For example, if the cosmic microwave background dominates the z ∼ 8 radio background, the new HERA limits imply that the first galaxies produced X-rays more efficiently than local ones. The z ∼ 10 limits require even earlier heating if dark-matter interactions cool the hydrogen gas. If an extra radio background is produced by galaxies, we rule out (at 95% confidence) the combination of high radio and low X-ray luminosities of L r,ν /SFR > 4 × 1024 W Hz−1 M ⊙ − 1 yr and L X /SFR < 7.6 × 1039 erg s−1 M ⊙ − 1 yr. The new HERA upper limits neither support nor disfavor a cosmological interpretation of the recent Experiment to Detect the Global EOR Signature (EDGES) measurement. The framework described here provides a foundation for the interpretation of future HERA results.

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Dislocation Vector Analysis Method of Deep Dislocation Having C-Axis Segment in Diamond

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1004.519 ◽

2020 ◽

Vol 1004 ◽

pp. 519-524 ◽

Cited By ~ 1

Author(s):

Shinichi Shikata ◽

Naoya Akashi

Keyword(s):

Three Dimensional ◽

Vector Analysis ◽

X Rays ◽

Analysis Method ◽

Burgers Vector ◽

X Ray ◽

Semiconductor Crystals ◽

Low X ◽

X Ray Absorption ◽

Geometrical Relationship

X-ray topography is an effective tool to investigate dislocations in semiconductor crystals. Due to low X-ray absorption coefficients of diamond, X-rays can penetrate deep into the crystal. Thus, deep three-dimensional (3D) dislocations are projected on two-dimension (2D) film, which makes dislocation analysis particularly challenging. Dislocation vectors from the films obtained using a set of the same diffraction vectors were identified using topographical and geometrical analyses. The depth and position of the dislocations in a crystal that was projected on a film were determined using geometrical relationship. The proposed analysis method was verified by analyzing several dislocations using four <404> diffraction films. The types of dislocation were identified through Burgers vector analysis.

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Capillaries prepared from thin-walled heat-shrink poly(ethylene terephthalate) (PET) tubing for X-ray powder diffraction analysis

Powder Diffraction ◽

10.1154/1.2358361 ◽

2006 ◽

Vol 21 (4) ◽

pp. 323-325 ◽

Cited By ~ 1

Author(s):

Joseph H. Reibenspies ◽

Nattamai Bhuvanesh

Keyword(s):

Ethylene Terephthalate ◽

X Rays ◽

X Ray ◽

Long Wavelength ◽

X Ray Scattering ◽

Poly Ethylene Terephthalate ◽

Thin Walled ◽

Poly Ethylene ◽

Low X ◽

X Ray Absorption

Thin-walled heat-shrink poly(ethylene terephthalate) (PET) tubing is reported for use as an alternative for glass and Kapton® capillaries. PET tubing displays properties such as low X-ray absorption and smooth diffraction profiles. The 2.0 mm thin-walled (0.05 mm thick) and 0.5 mm thin-walled (0.02 mm thick) heat-shrink PET capillaries are 86% and 96% transparent to 1.54 Å X-rays. The low X-ray absorption and relatively smooth X-ray scattering profile of PET make it an ideal material for the home laboratory where the long wavelength, low flux, and low brilliance X-ray sources are employed. PET capillaries can be easily cut and manipulated and fixed to copper pins, which in turn can be employed in low-temperature and automated data collection routines.

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Compatibility of X-ray computed tomography with plant gene expression, rhizosphere bacterial communities and enzyme activities

Journal of Experimental Botany ◽

10.1093/jxb/eraa262 ◽

2020 ◽

Vol 71 (18) ◽

pp. 5603-5614 ◽

Cited By ~ 1

Author(s):

Minh Ganther ◽

Bunlong Yim ◽

Zeeshan Ibrahim ◽

Manuela Desiree Bienert ◽

Eva Lippold ◽

...

Keyword(s):

Gene Expression ◽

Computed Tomography ◽

Enzyme Activities ◽

Growth Parameters ◽

Expression Patterns ◽

X Rays ◽

X Ray ◽

Antioxidative Enzyme Activities ◽

X Ray Computed ◽

Low X

Abstract Non-invasive X-ray computed tomography (XRCT) is increasingly used in rhizosphere research to visualize development of soil–root interfaces in situ. However, exposing living systems to X-rays can potentially impact their processes and metabolites. In order to evaluate these effects, we assessed the responses of rhizosphere processes 1 and 24 h after a low X-ray exposure (0.81 Gy). Changes in root gene expression patterns occurred 1 h after exposure with down-regulation of cell wall-, lipid metabolism-, and cell stress-related genes, but no differences remained after 24 h. At either time point, XRCT did not affect either root antioxidative enzyme activities or the composition of the rhizosphere bacterial microbiome and microbial growth parameters. The potential activities of leucine aminopeptidase and phosphomonoesterase were lower at 1 h, but did not differ from the control 24 h after exposure. A time delay of 24 h after a low X-ray exposure (0.81 Gy) was sufficient to reverse any effects on the observed rhizosphere systems. Our data suggest that before implementing novel experimental designs involving XRCT, a study on its impact on the investigated processes should be conducted.

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Development, Characterization and Valuable Use of Novel Dosimeter Film Based on PVA Polymer Doped Nitro Blue Tetrazolium Dye and AgNO3 for the Accurate Detection of Low X-ray Doses

Polymers ◽

10.3390/polym13183140 ◽

2021 ◽

Vol 13 (18) ◽

pp. 3140

Author(s):

Saleh Alashrah ◽

Yassine El-Ghoul ◽

Faisal Muteb Almutairi ◽

Mohammed Ahmed Ali Omer

Keyword(s):

Structural Changes ◽

Radiation Detection ◽

Nitro Blue Tetrazolium ◽

Diagnostic Radiology ◽

Nanocomposite Films ◽

X Rays ◽

X Ray ◽

Blue Tetrazolium ◽

Accurate Detection ◽

Low X

Currently, the uncontrolled exposure of individuals to X-rays during medical examinations represents a substantial danger that threatens both medical professionals and patients. Therefore, radiation dosimetry for low X-ray doses is a very important control of radiation practice in medical diagnostic radiology. In line with this, the current study proposes a valuable dosimeter-based PVA thin film doubly doped with silver nitrate salt and nitro blue tetrazolium dye. The nanocomposite film was prepared via a simple casting method and the different processing parameters were optimized. The performance of radiation detection was evaluated according to optical, chromic, chemical and structural changes after exposure to variable low X-ray doses (0, 2, 4, 10 and 20 mGy). The different film labels exhibited an excellent stability behavior in dark and light upon 30 days of storage. The UV-Vis spectrophotometric study showed a gradual increase in the maximum absorbance as a function of the dose and the corresponding response curve confirmed this linear variation (R = 0.998). A clear structural modification was recorded via X-ray diffraction (XRD) analysis revealing the increase in crystallinity with the level of the dose received by the nanocomposite films. Microscopic surface analysis via SEM assessments revealed a significant morphological change in PVA/Ag+/NBT films exposed to increased radiation doses and typical dendrites growing in needle- or tree-like microstructures appeared with a high X-ray dose. Finally, the nanocomposite films before and after irradiation were evaluated via a spectrocolorimetric study and the different CIELab coordinates, the color difference, as well as the color strength, showed a linear correlation with the intensity of the applied dose. This new dosimeter design could, therefore, provide a promising and efficient alternative for prompt and accurate detection of low X-rays doses in diagnostic radiology.

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Optical and X-ray study of the peculiar high-mass X-ray binary XMMU J010331.7−730144

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1739 ◽

2020 ◽

Vol 496 (3) ◽

pp. 3615-3622

Author(s):

I M Monageng ◽

M J Coe ◽

D A H Buckley ◽

V A McBride ◽

J A Kennea ◽

...

Keyword(s):

Gravitational Lensing ◽

High Mass ◽

Optical Data ◽

X Rays ◽

X Ray ◽

Radial Extent ◽

Mass Outflow ◽

Long Time ◽

Be Star ◽

Low X

ABSTRACT For a long time XMMU J010331.7−730144 was proposed as a high-mass X-ray binary candidate based on its X-ray properties, however, its optical behaviour was unclear – in particular previous observations did not reveal key Balmer emission lines. In this paper, we report on optical and X-ray variability of the system. XMMU J010331.7–730144 has been monitored with the Optical Gravitational Lensing Experiment (OGLE) in the I and V bands for the past 9 yr where it has shown extremely large amplitude outbursts separated by long periods of low-level flux. During its most recent optical outburst we obtained spectra with the Southern African Large Telescope (SALT) where, for the first time, the H α line is seen in emission, confirming the Be nature of the optical companion. The OGLE colour–magnitude diagrams also exhibit a distinct loop that is explained by changes in mass-loss from the Be star and mass outflow in its disc. In the X-rays, XMMU J010331.7−730144 has been monitored by the Neil Gehrels Swift Observatory through the S-CUBED programme. The X-ray flux throughout the monitoring campaign shows relatively low values for a typical Be/X-ray binary system. We show, from the analysis of the optical data, that the variability is due to the Be disc density and opacity changing rather than its physical extent as a result of efficient truncation by the NS. The relatively low X-ray flux can then be explained by the neutron star normally accreting matter at a low rate due to the small radial extent of the Be disc.

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CHROMOSOME REARRANGEMENTS AFTER LOW X-RAY DOSES GIVEN TO SPERMATOGONIA OF MICE

Canadian Journal of Genetics and Cytology ◽

10.1139/g68-016 ◽

1968 ◽

Vol 10 (1) ◽

pp. 119-124 ◽

Cited By ~ 25

Author(s):

A. Léonard ◽

Gh. Deknudt

Keyword(s):

Regression Coefficient ◽

Whole Body ◽

X Rays ◽

Male Mice ◽

Drying Method ◽

Air Drying ◽

X Ray ◽

Abnormal Cells ◽

Low X ◽

The Relationship

Male mice from the BALB/c strain were given whole-body irradiation at doses of 25, 50, 75 and 100 R of X-rays. Seventy days after irradiation the mice were killed, the testes removed and meiotic preparations were made using an air-drying method. Translocation configurations involving four chromosomes were the most frequent type recorded. The percentage of translocations increased regularly from 0.42 after 25 R to 1.96 after 100 R. The relationship between the X-ray dose and the rate of abnormal cells appears to be linear with a regression coefficient of b = 0.018960.

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PHOTONEUTRON EMISSION FROM Th232, U233, U238, AND Pu239

Canadian Journal of Physics ◽

10.1139/p57-052 ◽

1957 ◽

Vol 35 (4) ◽

pp. 470-476 ◽

Cited By ~ 4

Author(s):

L. Katz ◽

K. G. McNeill ◽

M. LeBlanc ◽

F. Brown

Keyword(s):

Cross Section ◽

Spontaneous Fission ◽

Heavy Elements ◽

X Rays ◽

Yield Curves ◽

X Ray ◽

Low X

Measurements have been made of the numbers of neutrons emitted by the fissile materials Th232, U233, U238, and Pu239 under irradiation by betatron X-rays of various energies up to 23 Mev. Yield curves and corresponding cross section curves are given for these nuclides. At low X-ray energies it is found that the yield curves differ from those found with non-fissile heavy elements, corresponding to the fact that even at zero X-ray energy the fissile materials suffer (spontaneous) fission.

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