It is an established fact that radon progeny can induce lung cancers. However, there is a well-known discrepancy between the epidemiologically derived dose conversion factor for radon progeny (4 mSv/WLM) and the dosimetrically derived value (15 mSv/WLM) (mSv is a unit of the dose while WLM is a unit of exposure to radon progeny). Up to now there is no satisfactory explanation to this. In the pr...

The embryonic thymus is colonized by the influx of hemopoietic progenitors in waves. To characterize the T cell progeny of the initial colonization waves, we used intravenous adoptive transfer of bone marrow progenitors into congenic embryos. The experiments were performed in birds because intravenous cell infusions can be performed more efficiently in avian than in mammalian embryos. Progenito...

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Lethal sectoring (LS) is the process for survival in which lethal damage remaining in irradiated cells is eliminated as lethal sector (offspring without reproductive integrity). This process occurs through the postirradiation 1st to 4th divisions with the accompanying appearance of a clonogenic progenitor (clonogen) (clonogenic sectoring: CS). The features of LS or CS and genomic instability (G...

The mode of inheritance of salt-dependent hypertension in the inbred Dahl salt-sensitive rat strain was examined by genetic crosses with the corresponding salt-resistant strain. The blood pressure responses to ingestion of a high NaCl (8%) diet defined three phenotypes: early onset (within 17 days) of systolic hypertension, defined as greater than or equal to 140 mm Hg, the parental salt-sensit...

Question: Is alpha radiation responsible for major changes in genome structure, including karyotypic change and higher ploidy? In vitro, high doses of alpha radiation yield many chromosomal changes, while low doses yield mostly point mutations. Data description: Previously published data on karyotypic variability and the incidence of polyploidy in various animal and plant species. Search method...

We developed the theoretical basis for long-term determination of airborne concentrations of unattached and attached radon progeny. The work was separated into two parts. First, we showed that (stacked and multiply etched) LR 115 detectors could be used to determine airborne concentrations of the short-lived radon progeny, Po and Bi. The equilibrium factor F between radon and its progeny could ...

Sexual crosses were used to determine the genetic basis of resistance to the sterol 14 alpha-demethylase inhibitor fungicide prochloraz in the cereal eyespot pathogen Tapesia yallundae. Three different crosses between sensitive parental strains (22-432 and 22-433 [the concentration required to inhibit growth by 50% (IG(50)) for each was </=0.03 mg/liter]) and field isolates from France and New ...

A biodosimetric approach to determine alpha-particle dose to the respiratory tract epithelium from known exposures to radon has been developed in the rat. Cytotoxicity assays have been used to obtain dose-conversion factors for cumulative exposures typical of those encountered by underground uranium miners. However, this approach is not sensitive enough to derive dose-conversion factors for ind...

The primary goal of this PhD research was to obtain critical information needed to further calibrate the novel glass-based retrospective radon detectors (RRDs) by characterizing the quantitative relationship between radon gas concentrations, the surface-deposited activities of various radon progeny, the airborne dose rate, and various residential environmental factors through both actual field ...