Some novel features of post-500°C heating blue stimulated OSL emission of fired natural quartz

Abstract In this study, some novel features of the post 500°C blue stimulated optically stimulated luminescence (OSL) of fired geological quartz are reported. Different observations (i) pulse annealing and (ii) impact of bleaching on high temperature TL glow peak suggested 510°C (heating rate of 2°C/s) TL peak trap to be responsible for the observed emission. The dosimetric properties of this emission were seen to make its applicability for dose assessment till kGy range. The signal was seen to be easily bleachable, reaching background value within 100 s with blue light at 125°C. The signal qualified all the tests (i) reproducibility, (ii) negligible recuperation and (iii) accuracy of dose recovery needed for reliable assessment of the radiation dose with modified Single aliquot regenerative (SAR) protocol. Considering the bleachability and high dynamic dose range of this signal, it has the potential to stretch the upper dose limit of dating by one order of magnitude than possible with conventional OSL, corresponding to 325°C TL trap. So, combining all the results, the signal reported here could be very useful for dosimetric applications involving measurement of high radiation dose, like dating.

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ESTIMATION OF Hp(3) TO THE EYE LENS OF INTERVENTIONAL RADIOLOGISTS—RELATION BETWEEN THE EYE LENS DOSE AND RADIOLOGIST’S HEIGHT

Radiation Protection Dosimetry ◽

10.1093/rpd/ncz181 ◽

2019 ◽

Vol 187 (4) ◽

pp. 409-417 ◽

Cited By ~ 3

Author(s):

Takuro Tanaka ◽

Kosuke Matsubara ◽

Atsushi Fukuda ◽

Satoshi Kobayashi

Keyword(s):

Interventional Radiology ◽

Radiation Dose ◽

Dose Reduction ◽

Optically Stimulated Luminescence ◽

Reduction Ratio ◽

Eye Lens ◽

Median Dose ◽

Dose Limit ◽

Lead Apron ◽

Occupational Radiation

Abstract The aim of the study was to estimate occupational radiation dose to the eye lens of radiologists and the dose reduction ratio of lead glasses during interventional radiology. Three interventional radiologists monitored Hp(3) using small-type optically stimulated luminescence dosemeters attached to the left inside and outside of the lead glasses with 0.07-mmPb [Hp(3)eye]. Hp(10) and Hp(0.07) were monitored, respectively, by attaching the personal dosemeter to the lead neck collar above the lead apron. The median Hp(3)eye with lead glasses and the median dose reduction ratio of lead glasses for the three radiologists were 8.02 mSv/y and 57.7%, respectively. The median Hp(3)eye without lead glasses [Hp(3)eye-w/o] for the three radiologists was 18.6 mSv/y, but Hp(3)eye-w/o for one of the radiologists was 24.1 mSv/y. Monitoring occupational radiation dose to the eye lens is important because interventional radiologists are at risk of exceeding the new dose limit.

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Radiation Dose Assessment of the Fog Lead Acrylic Shields during Coronary Angiography: A Phantom Study

Applied Sciences ◽

10.3390/app112210743 ◽

2021 ◽

Vol 11 (22) ◽

pp. 10743

Author(s):

Hsin-Hon Lin ◽

Lu-Han Lai ◽

Kuo-Ting Tang ◽

Chien-Yi Ting ◽

Cheng-Shih Lai

Keyword(s):

Radiation Dose ◽

Coronary Angiography ◽

Image Intensifier ◽

Optically Stimulated Luminescence ◽

Dose Assessment ◽

Conventional Coronary Angiography ◽

Average Dose ◽

Lead Glass ◽

Post Surgery ◽

Thyroid Glands

This study aimed to evaluate the effects of fogging on the effectiveness of a lead glass shield in protecting an operator from radiation exposure during conventional coronary angiography (CAG). Optically stimulated luminescence dosimeters (OSLDs) were used to measure the effects of fogged lead glass shields (FLSs) and clear lead glass shields (CLSs) on the radiation doses of a cardiac catheterization surgeon. We simulated the scatter radiation incident on the operator with five angiographic projections with 10-s exposures. Experiments were conducted with a field of view of 25 cm, maximum of 100 cm between the X-ray tube and image intensifier, and 80 cm between the image intensifier and operator. Lead glass fogging had no significant effect at any angiographic projection. The average dose at the lens of the eye, thyroid glands, and gonads did not differ significantly between FLS and CLS. Although most surgeons view ceiling-suspended shields as hindrances during surgical procedures, the radiation dose at the operator’s eyes and thyroid glands increased by 13 and 10 times without the shield. The fogging of the shield is probably caused by post-surgery UV decontamination or detergents. An operator has no cause for concern regarding the radiation protection afforded by an FLS during CAG procedures.

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88. Aquaculture-an Industry with High Radiation Dose Potential

10.3320/1.2763409 ◽

1999 ◽

Author(s):

A. Scott

Keyword(s):

Radiation Dose ◽

High Radiation ◽

High Radiation Dose

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Radiation Awareness for Endovascular Abdominal Aortic Aneurysm Repair in the Hybrid Operating Room: An Instant Operator Risk Chart for Daily Practice

Journal of Endovascular Therapy ◽

10.1177/15266028211007458 ◽

2021 ◽

pp. 152660282110074

Author(s):

Quirina M. B. de Ruiter ◽

Frans L. Moll ◽

Constantijn E. V. B. Hazenberg ◽

Joost A. van Herwaarden

Keyword(s):

Radiation Dose ◽

Dose Rate ◽

Effect Size ◽

Radiation Risk ◽

Dose Limit ◽

Access Site ◽

Femoral Access ◽

Dose Rates ◽

Rate Prediction ◽

Operator Dose

Introduction: While the operator radiation dose rates are correlated to patient radiation dose rates, discrepancies may exist in the effect size of each individual radiation dose predictors. An operator dose rate prediction model was developed, compared with the patient dose rate prediction model, and converted to an instant operator risk chart. Materials and Methods: The radiation dose rates (DRoperator for the operator and DRpatient for the patient) from 12,865 abdomen X-ray acquisitions were selected from 50 unique patients undergoing standard or complex endovascular aortic repair (EVAR) in the hybrid operating room with a fixed C-arm. The radiation dose rates were analyzed using a log-linear multivariable mixed model (with the patient as the random effect) and incorporated varying (patient and C-arm) radiation dose predictors combined with the vascular access site. The operator dose rate models were used to predict the expected radiation exposure duration until an operator may be at risk to reach the 20 mSv year dose limit. The dose rate prediction models were translated into an instant operator radiation risk chart. Results: In the multivariate patient and operator fluoroscopy dose rate models, lower DRoperator than DRpatient effect size was found for radiation protocol (2.06 for patient vs 1.4 for operator changing from low to medium protocol) and C-arm angulation. Comparable effect sizes for both DRoperator and DRpatient were found for body mass index (1.25 for patient and 1.27 for the operator) and irradiated field. A higher effect size for the DRoperator than DRpatient was found for C-arm rotation (1.24 for the patient vs 1.69 for the operator) and exchanging from femoral access site to brachial access (1.05 for patient vs 2.5 for the operator). Operators may reach their yearly 20 mSv year dose limit after 941 minutes from the femoral access vs 358 minutes of digital subtraction angiography radiation from the brachial access. Conclusion: The operator dose rates were correlated to patient dose rate; however, C-arm angulation and changing from femoral to brachial vascular access site may disproportionally increase the operator radiation risk compared with the patient radiation risk. An instant risk chart may improve operator dose awareness during EVAR.

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Out‐of‐field dose assessment for a 1.5 T MR‐Linac with optically stimulated luminescence dosimeters

Medical Physics ◽

10.1002/mp.14839 ◽

2021 ◽

Author(s):

Yan Zhang ◽

Shaojie Yan ◽

Zhen Cui ◽

Yungang Wang ◽

Zhenjiang Li ◽

...

Keyword(s):

Optically Stimulated Luminescence ◽

Dose Assessment

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Occupational Radiation Dose Limit to the Embryo and Foetus

Australasian Radiology ◽

10.1111/j.1440-1673.1978.tb02597.x ◽

1978 ◽

Vol 22 (2) ◽

pp. 104-104

Author(s):

P. L. T. ILBERY

Keyword(s):

Radiation Dose ◽

Dose Limit ◽

Occupational Radiation

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PRELIMINARY EVALUATION OF PATIENT RADIATION DOSES DURING RADIONUCLIDE DIAGNOSTIC WITH MONOCLONAL ANTIBODIES LABELED WITH 89Zr

Pharmacy Formulas ◽

10.17816/phf81118 ◽

2021 ◽

Author(s):

Larisa A. Chipiga ◽

Anna E. Petrova ◽

Artem A. Mosunov ◽

Laura T. Naurzbaeva ◽

Stanislaus M. Kushnarenko ◽

...

Keyword(s):

Monoclonal Antibodies ◽

Dose Assessment ◽

Published Data ◽

Radiation Doses ◽

Preliminary Evaluation ◽

Software Products ◽

Absorbed Doses ◽

Order Of Magnitude ◽

Effective Doses

In connection with the constantly increasing use of monoclonal antibodies labeled with 89Zr, in clinical practice, it is urgent to study their pharmacokinetics with the determination, based on the data obtained, of absorbed doses in tumor foci, as well as intact organs and tissues, and effective doses of patients. To date, there are a limited number of studies that provide patient doses for diagnostic examinations using 89Zr-labeled monoclonal antibodies. In this regard, the purpose of this work was to assess the biodistribution of various monoclonal antibodies (ramucirumab, trastuzumab, atezolizumab) labeled with 89Zr, based on published data, with subsequent calculation of absorbed doses in radiosensitive organs and tissues and effective doses of patients. Based on the analysis of experimental data on the biodistribution of monoclonal antibodies labeled with 89Zr for the diagnosis of oncological diseases from the available literature sources and our own assessments, it has been concluded that the results of the determination of absorbed in organs and tissues and effective doses are inconsistent. The absorbed doses in organs, according to different literature sources, vary up to an order of magnitude within one organ and reach 440 mGy per examination, the effective dose varies from 3 to 112 mSv per examination. This may be due to differences in study design, radiometry and dose assessment methods. Comparison with doses obtained on the basis of a general model of biodistribution of monoclonal antibodies demonstrates the possibility of using this model for a rough estimate of internal doses of patients. However, for a more accurate assessment, it is necessary to standardize approaches to the determination of internal radiation doses using the most effective methodological solutions and software products.

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