Dispersion and ground deposition of radioactive material according to airflow patterns for enhancing the preparedness to N/R emergencies

During nuclear accidents, decision-makers need to handle considerable data to take appropriate protective actions to protect people and the environment from radioactive material release. In such scenarios, machine learning can be an essential tool in facilitating the protection action decisions that will be made by decision-makers. By feeding machines software with big data to analyze and identify nuclear accident behavior, types, and the concentrations of released radioactive materials can be predicted, thus helping in early warning and protecting people and the environment. In this study, based on the ground deposition concentration of radioactive materials at different distances offsite in an emergency planning zone (EPZ), we proposed classification and regression models for three severe accidents. The objective of the classification model is to recognize the transient situation type for taking appropriate actions, while the objective of the regression model is to estimate the concentrations of the released radioactive materials. We used the Personal Computer Transient Analyser (PCTRAN) Advanced Power Reactor (APR) 1400 to simulate three severe accident scenarios and to generate a source term released to the environment. Additionally, the Radiological Consequence Analysis Program (RCAP) was used to assess the off-site consequences of nuclear power plant accidents and to estimate the ground deposition concentrations of radionuclides. Moreover, ground deposition concentrations at different distances were used as input data for the classification and regression tree (CART) models to obtain an accident pattern and to establish a prediction model. Results showed that the ground deposition concentration at a near distance from a nuclear power plant is a more informative parameter in predicting the concentration of radioactive material release, while the ground deposition concentration at a far distance is a very informative parameter in identifying accident types. In the regression model, the R-square of the training and test data was 0.995 and 0.994, respectively, showing a mean strong linear relationship between the predicted and actual concentration of radioactive material release. The mean absolute percentage error was found to be 26.9% and 28.1% for the training and test data, respectively. In the classification model, the model predicted a scenario (1) of 99.8% and 98.9%, scenario (2) of 98.4% and 91.6%, and scenario (3) of 98.6% and 94.7% for the training and test data, respectively.

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Studies on Metabolism of Urokinase and Mechanism of Thrombolysis by Urokinase

Thrombosis and Haemostasis ◽

10.1055/s-0038-1666937 ◽

1979 ◽

Vol 42 (03) ◽

pp. 885-894 ◽

Cited By ~ 13

Author(s):

Tatsuo Ueno ◽

Norio Kobayashi ◽

Tadashi Maekawa

Keyword(s):

Molecular Weight ◽

Plasma Clearance ◽

Radioactive Material ◽

Optimal Dosage ◽

Plasma Clot ◽

Optimal Dosage Regimen ◽

Arterial Thrombus ◽

Contact Experiment

SummaryPharmacokinetics of intravenously injected 125I-labeled urokinase (125I-UK) of a molecular weight of 33,000 daltons in normal rabbits and patients with various diseases were investigated. The plasma clearance of 125I-UK in rabbits was described by a biexponential curve within six hours with a half-life of 8 minutes, 2.3 hours, respectively. The radioactivity in the liver and kidneys 15 minutes after iv injection with 125I-UK was 9.6% and 14.0% of the radioactivity injected, respectively. Approximately 80% of the total radioactive material injected was excreted in the urine in 18 hours. No increase in activator activity in the urine was observed after a large amount of UK injection. Activity uptake of 125I-UK by experimentally induced arterial thrombus was little. Lysis of the stasis thrombus was produced by injecting 7.5 × 104 IU of UK in only one out of 8 rabbits. In vitro contact experiment revealed that transfer of 125I-UK to plasma clot is slow (24 hours for 10% of 125I-UK by plasma clot). In 4 patients plasma clearance of 125I-UK was essentially similar to that in rabbits. From the results obtained optimal dosage regimen of UK administration for complete thrombolysis in vivo was discussed.

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LACK OF AROMATISATION OF CIRCULATING DEHYDROEPIANDROSTERONE AND DEHYDROEPIANDROSTERONE SULPHATE IN AMENORRHOEIC WOMEN STIMULATED WITH HUMAN GONADOTROPHINS

Acta Endocrinologica ◽

10.1530/acta.0.0490248 ◽

1965 ◽

Vol 49 (2) ◽

pp. 248-261 ◽

Cited By ~ 8

Author(s):

S. Mancuso ◽

Francesca P. Mancuso ◽

K.-G. Tillinger ◽

E. Diczfalusy

Keyword(s):

Pregnant Women ◽

Ovarian Stimulation ◽

Interstitial Cell ◽

Follicular Phase ◽

Radioactive Material ◽

Dehydroepiandrosterone Sulphate ◽

Experimental Conditions ◽

Human Menopausal Gonadotrophin ◽

Urine Specimens ◽

Stimulating Hormone

ABSTRACT Two amenorrhoeic women were given a course of 10 injections of human menopausal gonadotrophin (HMG) in daily doses corresponding to 260 IU of follicle stimulating hormone (FSH) activity and 165 IU of interstitial cell stimulating hormone (ICSH) activity. In both patients an extensive ovarian stimulation was observed as indicated by the greatly increased urinary excretion of oestrone, 17β-oestradiol and oestriol. When HMG-treatment was followed subsequently by the administration of human chorionic gonadotrophin (HCG) for 5 days in a total dose of 18 000 and 30 000 IU, respectively, functional corpus luteum tissue was formed in both patients as evidenced by a huge rise in urinary pregnane-3α,20α-diol excretion and by the secretory transformation of a previously atrophic endometrium. At the approximate height of the follicular phase tracer doses of 3H-labelled dehydroepiandrosterone sulphate (DHAS) and 14C-labelled dehydroepiandrosterone (DHA) were administered to both patients in the form of a continuous intravenous infusion of 10 hours' duration. Infusion of the same dose was repeated under identical experimental conditions at the approximate height of the luteal phase. In both patients, very little radioactive material was associated with oestrone and 17β-oestradiol and none with oestriol isolated from 96-hours' urine specimens obtained at both phases of ovarian stimulation. It is concluded that — in contradistinction to the situation in pregnant women — circulating DHAS is not a significant precursor of urinary oestrogens in non-pregnant women.

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STUDIES ON THE AROMATISATION OF NEUTRAL STEROIDS IN PREGNANT WOMEN

Acta Endocrinologica ◽

10.1530/acta.0.0450535 ◽

1964 ◽

Vol 45 (4) ◽

pp. 535-559 ◽

Cited By ~ 88

Author(s):

E. Bolté ◽

S. Mancuso ◽

G. Eriksson ◽

N. Wiqvist ◽

E. Diczfalusy

Keyword(s):

Pregnant Women ◽

Comparative Studies ◽

Chorionic Gonadotrophin ◽

Human Chorionic Gonadotrophin ◽

Radioactive Material ◽

Placental Barrier ◽

Therapeutic Abortion ◽

Limited Ability ◽

Better Than

ABSTRACT In 15 cases of therapeutic abortion by laparotomy the placenta was disconnected from the foetus and perfused in situ with tracer amounts of radioactive dehydroepiandrosterone (DHA), dehydroepiandrosterone sulphate (DHAS), androst-4-ene-3,17-dione (A), testosterone (T) and 17β-oestradiol (OE2). Analysis of the placentas, perfusates and urine samples revealed an extensive aromatisation of DHA, A and T; more than 70% of the radioactive material recovered was phenolic, and at least 80 % of this phenolic material was identified as oestrone (OE1), 17β-oestradiol (OE2) and oestriol (OE3), the latter being detected only in the urine. Comparative studies indicated that A and T were aromatised somewhat better than DHA and that all three unconjugated steroids were aromatised to a much greater extent than DHAS. Radioactive OE1 and OE2 were isolated and identified in the placentas and perfusates, but no OE3, epimeric oestriols, or ring D ketols could be detected in these sources, not even when human chorionic gonadotrophin (HCG) was added to the blood prior to perfusion. Lack of placental 16-hydroxylation was also apparent when OE2 was perfused. Regardless of the precursor perfused, there was three times more OE2 than OE1 in the placenta and three times more OE1 than OE2 in the perfusate. This was also the case following perfusion with OE2. The results are interpreted as suggesting the existence in the pregnant human of a placental »barrier« limiting the passage of circulating androgen. The barrier consists of a) limited ability to transfer directly DHAS and b) an enzymic mechanism resulting in the rapid and extensive aromatisation of the important androgens DHA, A and T.

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Determination of natural radionuclides in waste generated in the potable water treatment plants of the Zona da Mata of the state of Pernambuco- Brazil

Brazilian Journal of Radiation Sciences ◽

10.15392/bjrs.v7i2a.763 ◽

2019 ◽

Vol 7 (2A) ◽

Author(s):

Adriana Muniz De Almeida Albuquerque

Keyword(s):

Water Treatment ◽

Potable Water ◽

Natural Radionuclides ◽

The United States ◽

Radioactive Material ◽

Human Consumption ◽

Radiological Protection ◽

Natural Occurrence ◽

Water Treatment Plants ◽

Potable Water Treatment

The water purification procedure aims to obtain a product appropriate for human consumption, minimizing the presence of contaminants and toxic substances present in the water. Among these contaminants, some radionuclides of natural origin, such as uranium, thorium and their descendants, have been identified. Studies have shown that the stages of purification are quite effective in removing the radionuclides contained in water. The removal is due to co-precipitation of the radionuclides with the suspended materials and the precipitated material is accumulated and characterized as a Technologically Concentrated Natural Occurrence Radioactive Material (TENORM) by the United States Environmental Protection Agency (USEPA). This residue can present significant levels of radioactivity and, when discarded in the environment without any treatment, can generate a problem of environmental impact and a risk to the health of the population. In this way, some gamma emitters of the series of U, Th and the K-40 were determined in the residues generated at the Potable Water Treatment Plants – PWTPs in six municipalities of Pernambuco. The results obtain corroborate the classification of the residues generated in the PWTPs as concentrators of the radioactive components contained in the water supplied to the system and reinforce the need for the release to the environment, which is the usual way of disposal of this waste, to be carried out only after considering the radiological protection standards established.

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