Nuclear anomalies

The incidence of nuclear anomalies in bone marrow interphase cells significantly increased (p<0.05) in Chinese hamsters gavaged on 2 consecutive days with 2,500 and 5,000 mg/kg/day of Reofos 50 (Ciba-Geigy 1984a), but not in those dosed with 1,250 mg/kg/day. The types of anomalies used in scoring were single "Howell-Jolly" bodies, fragments of nuclei in erythrocytes, micronuclei in erythroblasts, micronuclei in leucopoietic cells, and polyploidal cells. 

A few inclusions are exceptional in that they show isotopic anomalies for virtually every element studied, notably in the heavier isotopes of O, Mg, Si, Ca, Ti etc. these have been called FUN (fractionation and unknown nuclear) anomalies by Wasserburg and his colleagues and they may be due to unmodified stellar ejecta that were incorporated into the solar nebula in a solid form in which they survived. 

Migliore L, Ventura L, Barale R, et al. 1989. Micronuclei and nuclear anomalies induced in the gastrointestinal epithelium of rats treated with formaldehyde. Mutagenesis 4 327-334. 

The simplest system exliibiting a nuclear hyperfme interaction is the hydrogen atom with a coupling constant of 1420 MHz. If different isotopes of the same element exhibit hyperfme couplings, their ratio is detemiined by the ratio of the nuclear g-values. Small deviations from this ratio may occur for the Femii contact interaction, since the electron spin probes the inner stmcture of the nucleus if it is in an s orbital. However, this so-called hyperfme anomaly is usually smaller than 1 %. 

Results of preliminary experiments showed that only root tip cells of V. faba, A. cepa, P. sativum and T. turgidum responded positively to the Feulgen procedure (Table 4), with an evident appearance of MN and ATT anomalies (Fig. 1), which were more abundant in V. faba than in P. sativum (Fig. 2). The other plant species examined yielded a poor staining of the nuclear material, thus discouraging their use in successive experiments. 

As such, nuclear contributions to the heat capacity due to the interaction between germanium crystalline electric field gradients and the quadrupole moments of boron nuclei could account for the observed onset of the Schottky anomaly. 

Highly publicized nuclear accidents such as those that occurred at Chernobyl and Three Mile Island must be considered anomalies. Nuclear power plants have multiple safety measures in place to prevent radiation leaks. The small amount of radioactive waste produced by nuclear reactors is controlled and usually contained in the plant facility. 

More than forty years ago, Lee and Yang [8] observed anomalies in the decay patterns of theta and tau mesons, which suggested to them that parity was not conserved for certain weak interactions involved in the (3-decay of radioactive nuclei. This Nobel-prize-winning prediction was experimentally validated by Wu et al., [9] who found that the longitudinally polarized electrons emitted during the (3-decay of Co nuclei had a notable (40%) left-handed bias, i.e., their spins were predominantly antiparallel to their directions of motion. These experiments established that parity violation and symmetry breaking occurred at the nuclear level. 

Refractory materials in primitive meteorites were investigated first as they have the best chance of escaping homogenization in the early solar system. Inclusions in C3 carbonaceous chondrites exhibit widespread anomalies for oxygen and the iron group elements. Only a few members, dubbed FUN (for Fractionated and Unknown Nuclear effects), also display anomalous compositions for the heavy elements. Anomalies in inclusions have generally been connected with explosive or supernova nucleosynthesis. 

The excess was first suggested to have a nuclear origin in stars. Almost pure O is produced in He-buming shells in massive stars, and in supemovae. On the other hand it has been shown that non-mass dependent fractionation can be produced in the laboratory by non-nuclear processes (Thiemens and Heidenreich 1983 Thiemens 1988). Similar non-linear effects have been found for O isotopes in atmospheric gases (Schueler et al. 1990 Thiemens et al. 1995). Although stellar nucleosynthesis is indeed at the origin of the O observed in the universe, the link between O isotopic anomalies in inclusions and nucleosynthesis is still under debate (Thiemens 1999 Clayton 2002). 

Dunn, C.E. 1982. The massive Wollaston Uranium Biogeochemical Anomaly in the boreal forest of Northern Saskatchewan, Canada. In Uranium Exploration Methods Review of the NEA/IAEA Research and Development Programme, Paris, France, 1 -4 June, 1982, OECD Nuclear Energy Agency, 477-491. 

A model of an ore geochemical system has been developed (Goldberg et al, 2003), which can be applied to ore entities of various categories ore bodies, deposits and ore regions. The nuclear section of the system contains a zone of accumulation of the principal ore and associated elements. The peripheral areas contain zones of depletion of ore-forming elements. Anomalies of siderophile elements (Ni, Co, Mn, Ti, V, Cr), which are the subject of this paper, are located on the periphery of the nuclear sections of these systems. 

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