Half-lives of radionuclides span more than 50 orders of magnitude. We characterize the probability distribution of this broad-range data set at the same time that we explore a method for fitting power laws and testing goodness-of-fit. It is found that the procedure proposed recently by Clauset et al. [SIAM Rev. 51, 661 (2009)] does not perform well as it rejects the power-law hypothesis even fo...

The absolute V light curves of 5 SNe Ia, selected to represent the known range of absolute luminosities at maximum for this class of objects, are presented. Comparison of the long term luminosity evolution shows that the differences seen at maximum persist, and actually increase with time, reinforcing the notion that intrinsic differences do exist among SNe Ia. Since such differences are not ac...

A cycloheximide-sensitive increase in the activity of phenylalanine ammonia-lyase (EC 4.3.1.5) occurs in Xanthium leaf disks exposed to light. Radioactive ammonia-lyase has been isolated by means of sucrose density gradient centrifugation and starch gel electrophoresis from disks fed l-isoleucine-U-(14)C or l-arginine-U-(14)C. The incorporation of radioactive amino acids into phenylalanine ammo...

In September 1987 an accident occurred with a cesium chloride (CsCl) teletherapy source taken from a cancer therapy institute in Goiânia, Brazil. Misuse of the abandoned source caused widespread contamination of radioactive material (about 50 TBq of Cs) in the town of Goiânia. Decontamination of affected areas did lead to about 3,500 m of solid radioactive wastes, which were disposed in two nea...

the present nuclear leakage crisis from japan is a topic to be discussed in present public health. in radiology, the leaked radioactive elements are considered hazard. here, the author briefly reviews and discusses on two important radio-hazard elements in post nuclear power plant crisis, radioactive iodine and radioactive cesium. based on previous similar nuclear crisis in russia, it is eviden...

Cultures of Escherichia coli will not grow in media containing very high specific activities of radiophosphorus P(32), the inhibition of growth being due to the decay of assimilated P(32) atoms. Experiments with a differentially labeled thymineless strain of E. coli show that the P(32) disintegrations which occur in the bacterial deoxyribonucleic acid, i.e. in the nucleus, are mainly responsibl...

Introduction ______________________________ Disposal of radioactive wastes in streams. Radioactivity budget in streams. ________ Characteristics of radioactive wastes which are discharged into streams______________________________ Sources of wastes.__--__--_--_-_-_______________ Nature of wastes.--__-------___-_______________ Properties and types of radionuclides________ Chemical and physical c...

Unstable atomic nuclei may decay into less energetic nuclei by emission of alpha, beta, and gamma radiation. These forms of radiation are now known to consist of He4 nuclei, electron (or positron), and high energy photons respectively. Which types of decay a nuclei may undergo depends on how it is unstable. Many materials may emit more than one form of radiation. This is especially true when th...