Jean Vankerkom

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Vegetation is often quoted as an effective measure to mitigate urban air quality problems. In this work we demonstrate by the use of computer models that the air quality effect of urban vegetation is more complex than implied by such general assumptions. By modelling a variety of real-life examples we show that roadside urban vegetation rather leads to(More)
Survival and causes of mortality were studied in 7- or 21-day-old male C57BL/Cnb mice exposed to 0.5, 1 or 3 Gy of 250 kVp X rays or 0.125, 0.25, 0.5 or 1 Gy of accelerator neutrons (modal energy 3.1 MeV). A total of 1287 animals were used in the experiments. Survival of irradiated animals was reduced significantly only in the mice receiving the highest(More)
Pregnant ewes have been chronically contaminated during pregnancy and lactation with Cs-134 administered as CsCl in the food. Plateau concentrations in excreta and blood were reached after about 20 d of contamination. At delivery, the contamination levels in lamb's tissue were lower than those in the corresponding organs from an ewe; they increased rapidly(More)
In order to assess the influence of p53 inactivation on radiation-induced developmental effects, male mice heterozygous for the wild-type p53 allele (mimicking the human Li-Fraumeni syndrome) were crossed with C57BL females, and their heterozygous p53+/- progeny were mated with each other to obtain p53+/-, p53-/- and p53+/+ embryos. Pregnant females were(More)
A comparison was made of the radiosensitivities of the resting oocyte of guinea pig in its two different states, the 'large' resting and 'contracted' oocyte, also extending the investigations to the radiosensitivity of the female germ cells at earlier stages during intrauterine life. The radiosensitivity of guinea pig oocytes was evaluated by testing the(More)
Female mice of the BALB/c and CF1 strains were mated and irradiated with various doses of X-rays 7 h after presumed fertilization. 18 days later, females were killed and their uteri examined for prenatal mortality at the different stages of development. Living fetuses were weighed and examined for the presence of external malformations. A number of them(More)
In vivo studies on X-irradiated mice have shown that structural chromosome aberrations can be induced in female germ cells and that the radiation-induced chromosomal damage strongly depends on the stage of maturation reached by the oocytes at the time of irradiation. In the present study, the sensitivity of oocytes to induction of chromosome damage by(More)
Technetium (Tc) released into the environment can reach animals in various chemical forms: as pertechnetate (TcO-4) in drinking water or deposited on the surface of vegetables and forage plants, or as Tc bioincorporated into plants and associated with various plant constituents. In addition to being influenced by chemical speciation in the diet, absorption,(More)
Recent results have shown that irradiation of a single cell, the zygote or 1-cell embryo of various mouse strains, could lead to congenital anomalies in the fetuses. In the Heiligenberger strain, a link between the radiation-induced congenital anomalies and the development of a genomic instability was also suggested. Moreover, further studies showed that in(More)
In female mammals, the immature oocyte is the germ cell most at risk, from the genetic point of view. We have previously shown that ovaries of newborn guinea pigs contain a great majority of immature oocytes and small numbers of maturing oocytes. At this time, all immature oocytes are in a typical diplotene stage, comparable to that of the human resting(More)