Atomic Energy of Canada Limited

About: Atomic Energy of Canada Limited is a company organization based out in Ottawa, Ontario, Canada. It is known for research contribution in the topics: Neutron & Zirconium alloy. The organization has 4845 authors who have published 4826 publications receiving 102951 citations.

Radiation-Induced Genetic Segregations in Vegetative Cells of Diploid Yeast.

Abstract: LTRAVIOLET irradiation frequently induces homozygosis a t one or more loci U in heterozygous vegetative cells of Saccharomyces cerevisiae. For a particular allelic pair, the observed frequency of such inductions can approach two percent among survivors under conditions where fewer than fifty percent of the irradiated cells are killed. These alterations are almost certainly due to genetic segregation rather than to gene mutation, since: (1) complementary types (homozygous recessive and homozygous dominant) often appear as different lines of descent from a single irradiated heterozygote, (2) irradiated haploids show only rare changes from dominant to recessive, and (3) irradiated homozygous recessive cells show only rare changes to heterozygous (JAMES 1953; 1955). However, the observed homozygosis could result either from independent segregations of individual loci or from linked segregations involving whole chromosomes or parts of chromosomes. The present investigation was undertaken to obtain information on the mechanism by which the segregants are produced.

The Effect of Irradiation on Ni-Containing Components in CANDU® Reactor Cores: A Review

Abstract: For nickel-containing alloys irradiated in thermalized neutron fluxes, the formation and reaction of 59 Ni with thermal neutrons can lead to time-varying changes in displacement damage rate, expres...

Photoreactivation of thymine dimers in UV-irradiated human cells: unique dependence on culture conditions.

Abstract: UV-irradiated human fibroblasts in tissue culture were exposed to photoreactivating light in an attempt to demonstrate a light-dependent loss of thymine dimers from the acid-insoluble fraction of the DNA. The only experimental conditions in which this phenomenon was observed was if the cells were grown for at least 10 days in Dulbecco's modified Eagle's minimum essential medium. Such cells lost a maximum of between 10–30% of the thymine dimers from their DNA during illumination for 1 h. When cells were grown in a variety of other media the phenomenon was not observed. The present experiments do not discriminate between true enzymatic photoreactivation and a medium-dependent photosensitization phenomenon that is not enzymatic in nature.

A sex pheromone in the insect rhodnius prolixus (hemiptera: reduviidae)

Abstract: In Rhodnius, a volatile substance produced by mating pairs is attractive to male insects. The pheromone acts also as a sexual stimulant; males respond in the absence of females by attempting copulation with other males. Air swept over mating pairs and conducted to a cage at a considerable distance proved to be highly attractive to males. Proximity of the sexes, without opportunity for actual contact, does not stimulate production of the pheromone. Since males and females will copulate only after a blood meal, feeding is a prerequisite to pheromone production. Also, unfed males will not respond to the attractant. Males of this nocturnal species were stimulated only in complete darkness.