Energetic Solar Particles and Radiation Hazard in Space

Author(s):  
Leonty I. Miroshnichenko
Science ◽  
1963 ◽  
Vol 142 (3599) ◽  
pp. 1587-1592 ◽  
Author(s):  
P. Freier ◽  
W. R. Webber

1984 ◽  
Vol 23 (02) ◽  
pp. 87-91 ◽  
Author(s):  
K. Flemming

SummaryIn the beginning of medical radiology, only the benefit of ionizing radiation was obvious, and radiation was handled and applied generously. After late effects had become known, the radiation exposure was reduced to doses following which no such effects were found. Thus, it was assumed that one could obtain an optimal medical benefit without inducing any hazard. Later, due to experimental findings, hypotheses arose (linear dose-effect response, no time factor) which led to the opinion that even low and lowest radiation doses were relevant for the induction of late effects. A radiation fear grew, which was unintentionally strengthened by radiation protection decrees: even for low doses a radiation risk could be calculated. Therefore, it was believed that there could still exist a radiation hazard, and the radiation benefit remained in question. If, however, all presently known facts are considered, one must conclude that large radiation doses are hazardous and low doses are inefficient, whereas lowest doses have a biopositive effect. Ionizing radiation, therefore, may cause both, hazard as well as benefit. Which of the two effects prevails is determined by the level of dose.


1979 ◽  
Vol 25 (6) ◽  
pp. 973-975 ◽  
Author(s):  
T Chard ◽  
A Sykes

Abstract We describe an immunoassay for human choriomammo-tropin by use of the fluorescein-labeled hormone (of human origin). The technique is generally similar to the radioimmunoassay for this material, but has the advantage of stability of tracer and avoidance of radiation hazard. However, the procedure requires approximately 50-fold more tracer than does the radioimmunoassay, and this would be a disadvantage with materials for which supplies of purified antigen are scarce. Furthermore, both within-assay variation (3.9%) and between-assay variation (7.8--7.9%) were less satisfactory than that of radioimmunoassay (1.5% and 2.2--3%, respectively). This is almost certainly the result of imprecision of end-point detection and could probably be corrected by further attention to equipment design.


2018 ◽  
Vol 80 (01) ◽  
pp. 059-066 ◽  
Author(s):  
Jeff Ehresman ◽  
Tomas Garzon-Muvdi ◽  
Davis Rogers ◽  
Michael Lim ◽  
Gary Gallia ◽  
...  

Object Meningiomas occur in various intracranial locations. Each location is associated with a unique set of surgical nuances and risk profiles. The incidence and risk factors that predispose patients to certain deficits based on tumor locations are unclear. This study aimed to determine which preoperative factors increase the risk of patients having new deficits after surgery based on tumor location for patients undergoing intracranial meningioma surgery. Methods Adult patients who underwent primary, nonbiopsy resection of a meningioma at a tertiary care institution between 2007 and 2015 were retrospectively reviewed. Stepwise multivariate logistic regression analyses were used to identify associations with postoperative deficits based on tumor location. Results Postoperatively, from the 761 included patients, there were 39 motor deficits (5.1%), 23 vision deficits (3.0%), 19 language deficits (2.5%), 27 seizures (3.5%), and 26 cognitive deficits (3.4%). The factors independently associated with any postoperative deficits were preoperative radiation (hazard ratio [HR] [95% confidence interval, CI] 3.000 [1.346–6.338], p = 0.008), cerebellopontine angle tumors (HR [95% CI] 2.126 [1.094–3.947], p = 0.03), Simpson grade 4 resections (HR [95% CI] 2.000 [1.271–3.127], p = 0.003), preoperative motor deficits (HR [95% CI] 1.738 [1.005–2.923], p = 0.048), preoperative cognitive deficits (HR [95% CI] 2.033 [1.144–3.504], p = 0.02), and perioperative pulmonary embolisms (HR [95% CI] 11.741 [2.803–59.314], p = 0.0009). Conclusion Consideration of the factors associated with postoperative deficits in this study may help guide treatment strategies for patients with meningiomas.


Space Weather ◽  
2015 ◽  
Vol 13 (9) ◽  
pp. 560-567 ◽  
Author(s):  
C. J. Joyce ◽  
N. A. Schwadron ◽  
L. W. Townsend ◽  
R. A. Mewaldt ◽  
C. M. S. Cohen ◽  
...  
Keyword(s):  

Author(s):  
Glenn Abramczyk ◽  
James Shuler ◽  
Steven J. Nathan ◽  
Allen C. Smith

The Small Gram Quantity (SGQ) concept is based on the understanding that small amounts of hazardous materials, in this case radioactive materials, are significantly less hazardous than large amounts of the same materials. The essential functional requirements for RAM packaging are containment of the material, ensuring sub-criticality, and ensuring that the radiation hazard of the package, as represented by the radiation dose for the package, is within the regulatory limits. Knowledge of the composition of the material being shipped is also required. By placing the contents in a containment vessel which is helium leaktight, and limiting the mass so that subcriticality is ensured, the first two requirements are readily met. Some materials emit sufficiently strong photon radiation that a small amount of material can yield a large dose rate. Foreknowledge of the dose rate which will be present for a proposed content is a challenging issue for the SGQ approach. Issues associated with certification for several cases of contents which fall within the SGQ envelop are discussed.


2012 ◽  
Vol 295 (2) ◽  
pp. 1293-1297 ◽  
Author(s):  
O. Díaz Rizo ◽  
A. Gelen Rudnikas ◽  
J. O. Arado López ◽  
K. D′Alessandro Rodríguez ◽  
P. González Hernández ◽  
...  

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