Alpha Particle Beam Interactions with Fe-Based and FeCo-Based Amorphous Magnets

1996 ◽  
Vol 438 ◽  
Author(s):  
Monica Sorescu ◽  
D. Barb
Keyword(s):  
Alpha Particle ◽  
Metallic Glasses ◽  
Conversion Electron ◽  
Particle Flux ◽  
Particle Beam ◽  
Radiation Doses ◽  
Particle Beams ◽  
Sample Composition ◽  
Radiation Induced ◽  
Amorphous Magnets

AbstractSamples of Fe78B13Si1 and Fe66Co18B15Si1 metallic glasses were irradiated with alpha particle beams (W=2.8 MeV) using radiation doses of 1016 and 1017 cm2. Irradiation-induced effects on the magnetic and structural properties of alloy samples were studied by transmission and conversion electron Mbssbauer spectroscopy. The evolution of phases and microstructure during the radiation-induced amorphous-to-crystalline transformation was found to depend on the particle flux and sample composition. Differences between bulk and surface irradiation behaviors were demonstrated.

Interaction of Alpha Particle Beams with Fe-Based and FeNi-Based Glassy Ferromagnets

1995 ◽  
Vol 396 ◽  
Author(s):  
Monica Sorescu ◽  
D. Barb
Keyword(s):  
Alpha Particle ◽  
Crystallization Process ◽  
Morphological Changes ◽  
Particle Beam ◽  
Particle Beams ◽  
Magnetic Texture ◽  
Ferromagnetic Alloys ◽  
Sample Composition ◽  
Radiation Induced ◽  
Amorphous Magnets

AbstractSamples of Fe78B13Si9 and Fe40Ni38Mo4B18 metallic glasses were irradiated with alpha particle beams (W=2.8 MeV) using radiation doses of 1016 and 1017 cm-2. Irradiation-induced effects on the magnetic texture and phase composition of alloy samples were studied by Mössbauer spectroscopy. Related morphological changes and resultant crystalline precipitates were characterized by scanning electron microscopy. The evolution of phases and microstructure during the radiation-induced amorphous-to-crystalline transformation was found to depend on the particle flux and sample composition. The lowest radiation dose employed was found to be more effective in inducing amorphous-to-crystalline transformations in both ferromagnetic alloys studied. In addition, the FeNi-based amorphous system investigated was found to be more stable than the Fe-based metallic glass, exposed to the same particle-beam irradiation conditions. By stimulating unconventional pathways for the crystallization process, the interaction of alpha particle beams with glassy ferromagnets offers unique opportunities to understand the fundamentals of nucleation and growth in amorphous magnets.

Interaction of alpha particle beams with metallic glasses

1998 ◽  
Vol 46 (15) ◽  
pp. 5523-5531 ◽  
Author(s):  
M Sorescu ◽  
D Barb
Keyword(s):  
Alpha Particle ◽  
Metallic Glasses ◽  
Particle Beams

scholarly journals Radiation-Induced Noncancer Risks in Interventional Cardiology: Optimisation of Procedures and Staff and Patient Dose Reduction

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Zhonghua Sun ◽  
Aini AbAziz ◽  
Ahmad Khairuddin Md Yusof
Keyword(s):  
Potential Risk ◽  
Medical Staff ◽  
Interventional Procedure ◽  
Cardiovascular Effects ◽  
Interventional Cardiology ◽  
Evidence Based ◽  
Radiation Doses ◽  
High Radiation ◽  
Radiation Induced ◽  
Patient Dose Reduction

Concerns about ionizing radiation during interventional cardiology have been increased in recent years as a result of rapid growth in interventional procedure volumes and the high radiation doses associated with some procedures. Noncancer radiation risks to cardiologists and medical staff in terms of radiation-induced cataracts and skin injuries for patients appear clear potential consequences of interventional cardiology procedures, while radiation-induced potential risk of developing cardiovascular effects remains less clear. This paper provides an overview of the evidence-based reviews of concerns about noncancer risks of radiation exposure in interventional cardiology. Strategies commonly undertaken to reduce radiation doses to both medical staff and patients during interventional cardiology procedures are discussed; optimisation of interventional cardiology procedures is highlighted.

scholarly journals Live-cell imaging to detect phosphatidylserine externalization in brain endothelial cells exposed to ionizing radiation: implications for the treatment of brain arteriovenous malformations

2016 ◽  
Vol 124 (6) ◽  
pp. 1780-1787 ◽  
Author(s):  
Zhenjun Zhao ◽  
Michael S. Johnson ◽  
Biyi Chen ◽  
Michael Grace ◽  
Jaysree Ukath ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Endothelial Cells ◽  
Ionizing Radiation ◽  
Live Cell Imaging ◽  
Cell Imaging ◽  
Live Cell ◽  
Vascular Targeting ◽  
Radiation Doses ◽  
Radiation Induced ◽  
Polarity Sensitive

OBJECT Stereotactic radiosurgery (SRS) is an established intervention for brain arteriovenous malformations (AVMs). The processes of AVM vessel occlusion after SRS are poorly understood. To improve SRS efficacy, it is important to understand the cellular response of blood vessels to radiation. The molecular changes on the surface of AVM endothelial cells after irradiation may also be used for vascular targeting. This study investigates radiation-induced externalization of phosphatidylserine (PS) on endothelial cells using live-cell imaging. METHODS An immortalized cell line generated from mouse brain endothelium, bEnd.3 cells, was cultured and irradiated at different radiation doses using a linear accelerator. PS externalization in the cells was subsequently visualized using polarity-sensitive indicator of viability and apoptosis (pSIVA)-IANBD, a polarity-sensitive probe. Live-cell imaging was used to monitor PS externalization in real time. The effects of radiation on the cell cycle of bEnd.3 cells were also examined by flow cytometry. RESULTS Ionizing radiation effects are dose dependent. Reduction in the cell proliferation rate was observed after exposure to 5 Gy radiation, whereas higher radiation doses (15 Gy and 25 Gy) totally inhibited proliferation. In comparison with cells treated with sham radiation, the irradiated cells showed distinct pseudopodial elongation with little or no spreading of the cell body. The percentages of pSIVA-positive cells were significantly higher (p = 0.04) 24 hours after treatment in the cultures that received 25- and 15-Gy doses of radiation. This effect was sustained until the end of the experiment (3 days). Radiation at 5 Gy did not induce significant PS externalization compared with the sham-radiation controls at any time points (p > 0.15). Flow cytometric analysis data indicate that irradiation induced growth arrest of bEnd.3 cells, with cells accumulating in the G2 phase of the cell cycle. CONCLUSIONS Ionizing radiation causes remarkable cellular changes in endothelial cells. Significant PS externalization is induced by radiation at doses of 15 Gy or higher, concomitant with a block in the cell cycle. Radiation-induced markers/targets may have high discriminating power to be harnessed in vascular targeting for AVM treatment.

Eye protection in interventional procedures

2021 ◽  
Vol 94 (1126) ◽  
pp. 20210436 ◽  
Author(s):  
Beth A. Schueler ◽  
Kenneth A Fetterly
Keyword(s):  
Interventional Procedures ◽  
Eye Lens ◽  
Radiation Doses ◽  
Radiation Induced ◽  
Individual Actions ◽  
Dose Measurements ◽  
Dose Levels ◽  
Patient Radiation Dose ◽  
Low Radiation Doses

Data suggest that radiation-induced cataracts may form without a threshold and at low-radiation doses. Staff involved in interventional radiology and cardiology fluoroscopy-guided procedures have the potential to be exposed to radiation levels that may lead to eye lens injury and the occurrence of opacifications have been reported. Estimates of lens dose for various fluoroscopy procedures and predicted annual dosages have been provided in numerous publications. Available tools for eye lens radiation protection include accessory shields, drapes and glasses. While some tools are valuable, others provide limited protection to the eye. Reducing patient radiation dose will also reduce occupational exposure. Significant variability in reported dose measurements indicate dose levels are highly dependent on individual actions and exposure reduction is possible. Further follow-up studies of staff lens opacification are recommended along with eye lens dose measurements under current clinical practice conditions.

scholarly journals Modeling of Respiratory System Dysfunction among Nuclear Workers: A Preliminary Study

Dose-Response ◽  
2008 ◽  
Vol 6 (4) ◽  
pp. dose-response.0 ◽  
Author(s):  
Z.D. Belyaeva ◽  
S.V. Osovets ◽  
B.R. Scott ◽  
G.V. Zhuntova ◽  
E.S. Grigoryeva
Keyword(s):  
Cigarette Smoking ◽  
Respiratory System ◽  
Respiratory Function ◽  
Radiation Doses ◽  
Alpha Radiation ◽  
Nuclear Workers ◽  
Chronic Radiation ◽  
Mayak Production Association ◽  
Radiation Induced ◽  
Total Body

Numerous studies have reported on cancers among Mayak Production Association (PA) nuclear workers. Other studies have reported on serious deterministic effects of large radiation doses for the same population. This study relates to deterministic effects (respiratory system dysfunction) in Mayak workers after relatively small chronic radiation doses (alpha plus gamma). Because cigarette smoke is a confounding factor, we also account for smoking effects. Here we present a new empirical mathematical model that was introduced for simultaneous assessment of radiation and cigarette-smoking-related damage to the respiratory system. The model incorporates absolute thresholds for smoking- and radiation-induced respiratory system dysfunction. As the alpha radiation dose to the lung increased from 0 to 4.36 Gy, respiratory function indices studied decreased, although remaining in the normal range. The data were consistent with the view that alpha radiation doses to the lung above a relatively small threshold (0.15 to 0.39 Gy) cause some respiratory system dysfunction. Respiratory function indices were not found to be influenced by total-body gamma radiation doses in the range 0–3.8 Gy when delivered at low rates over years. However, significant decreases in airway conductance were found to be associated with cigarette smoking. Whether the indicated cigarette smoking and alpha radiation associated dysfunction is debilitating is unclear.

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