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Androstenedione, a steroidal dietary supplement taken to enhance athletic performance, could affect serum and liver lipid metabolism, induce liver toxicity or alter inflammatory response depending on dose and duration of exposure. Pregnancy could further exaggerate these effects. To examine this, mature female rats were gavaged with 0, 5, 30 or 60 mg/kg/day androstenedione beginning two weeks prior to mating and continuing through gestation day 19. Non-pregnant female rats were gavaged over the same time frame with 0 or 60 mg/kg/day androstenedione. Serum was collected and livers were removed from dams on gestation day 20 and from non-pregnant rats after 5 weeks of treatment. Androstenedione had no effect on serum total cholesterol, triglycerides or HDL-cholesterol, but significantly decreased C-reactive protein in pregnant rats and prostaglandin E(2) in serum of both pregnant and non-pregnant rats. There were treatment related decreases in liver ATP and, to a lesser degree, caspase-3 and no change in alkaline phosphatase of pregnant female rats. Androstenedione decreased docosahexaenoic acid in both serum and liver phospholipids of pregnant female rats. In conclusion, oral androstenedione did not result in overt hepatotoxicity in pregnant female rats, but produced modest changes in lipid metabolism and may impair regeneration of injured hepatic cells or tissue.

This report describes the development of an operator procedure prompting aid for startup of a nuclear reactor. This operator aid is a preliminary design for a similar aid that eventually will be used with the Advanced Liquid Metal Reactor (ALMR) presently in the design stage. Two approaches were used to develop this operator procedure prompting aid. One method uses an expert system software shell, and the other method uses database software. The preliminary requirements strongly pointed toward features traditionally associated with both database and expert systems software. Database software usually provides data manipulation flexibility and user interface tools, and expert systems tools offer sophisticated data representation and reasoning capabilities. Both methods, including software and associated hardware, are described in this report. Proposals for future enhancements to improve the expert system approach to procedure prompting and for developing other operator aids are also offered. 25 refs., 14 figs.

A status report on an artificial intelligence (AI) environment procedure-prompting prototype is presented. This program would permit replacement of hard copy of the Experimental Breeder Reactor-II (EBR-II) written operating procedures for plant startup with a computerized procedures manual. It is expected that with this approach, the computerized system would be able to assist reactor operators and managers by making procedures available rapidly, displaying the appropriate procedure steps, and performing on-line checks of plant parameters when required. 14 refs.

The compositions of liquidus olivines and orthopyroxenes of natural specimens of spinifex- and quench-textured peridotitic komatiites from the Belingwe Greenstone Belt, Rhodesia have been determined for pressures between 10 and 40 kbars. In conjunction with the chemical variation exhibited by these peridotitic komatiites it is concluded that the more magnesian lavas cannot be derived by concentration of olivine phenocrysts, fractional crystallisation or equilibrium partial melting. The peridotitic komatiites could evolve by polybaric assimilation and complete melting of garnet lherzolite into an initial liquid containing about 24% MgO.

Marker chromosome analysis of 18 tetraparental AKR↔CBA/H-T6 chimaeras revealed a great excess of AKR mitoses over CBA mitoses in direct preparations from lymphomyeloid tissues, corneal epithelium, intestinal epithelium and skin (Table 1). The degree of AKR dominance was strongly influenced by anatomical site (Tables 2 and 3). The testes of three out of four XY/XY males contained a marked excess of AKR germ cells and produced a parallel excess of functional AKR gametes (Table 4). Mitotic spreads in mitogen-stimulated cultures of tail blood were overwhelmingly of AKR type in 1972, but less so in 1973 (Table 5). The coat phenotypes, and breeding results from known or presumptive XX/XX females, suggest that AKR and CBA cells were numerically balanced when melanoblasts and oocytes were formed during embryonic development, and therefore that the striking deviations from equality observed in mitotic populations of adult chimaeras arose later by differential proliferation or survival of AKR cells, or both. The low frequency of lymphomas, compared with normal AKR mice, previously reported in these chimaeras cannot therefore be accounted for by insufficiency of AKR cells in the thymus or elsewhere in the lymphomyeloid tissues. One of three lymphomas studied was CBA type. This suggests that the high risk of lymphomatous transformation is not an autonomous property of AKR cells.

In order to evaluate the effect of fluorine substitution on hornblende stability in basaltic melts, the upper stability of a synthetic pargasite with 43% of its OH sites replaced by fluorine was studied under fluid-absent conditions at pressures up to 35 kbars. The fluorohydroxy pargasite melts incongruently over an interval of 25–55°C depending on pressure. Liquid, amphibole, clinopyroxene, spinel, forsterite and garnet, at higher pressures, appear in the melting interval. Coordinates for the amphibole-out boundary are: 5 kbars, 1060°C; 15 kbars, 1230°C; 25 kbars, 1285°C; 30 kbars, 1290°C and 35 kbars, 1285°C. Substitution of F for OH in the amphibole structure increases both its temperature and pressure stability limits, and results in a substantial melting interval through which hornblende and melt coexist in fluid-absent situations. Partial melting events could produce fluorine-rich hornblende as a refractory, residual phase.

Some microprobe analyses of glasses from experimental samples are proved or implied to have different compositions from the equilibrium liquids present under the experimental conditions. Before a microprobe analysis of a glass is accepted as that of the liquid, its validity must be ascertained by alternative methods.

The karyotype analysis of a mentally retarded baby with persistence of embryonic and foetal haemoglobin showed three abnormal chromosomes. One was identified as a No. 3 with an extra segment, another as No. 6 or 7, or X, with a deletion and the last one was assigned to pair 15 by autoradiography. The parents of the propositus were both haematologically and chromosomally normal. The possible mechanisms of origin of the multiple chromosomal rearrangements arc discussed. The data are also compared with those reported by other authors in connection with different chromosomal abnormalities. Particular attention is paid to trisomy D, which has been found associated with persistence of foetal haemoglobin. Although the possibility of a nonspecific effect of the observed karyotypic alterations cannot be ruled out, the suggestion is made that one or more of the abnormal chromosomes are carriers of gene(s) controlling the synthesis of e and γ chains.

Translocation frequencies were studied in spermatocytes derived from the spermatogonia of mice given 300 rad X-rays in two equal fractions separated by intervals of 0–8 h. In the first experiment (0–2 h intervals) there was a significant fall from 14.5% to 8.1% in the frequency of affected cells when there was an 0.5-h interval between doses instead of a single dose, followed by a just significant rise to 10.8% at a 2-h interval. However, the translocation frequency after a single 300-rad dose was higher than expected from previous experiments at this level (see paper III of this series). In the second experiment (0–8 h intervals) there was again an initial fall (from 8.8% at 0 h to 6.6% at 1 h) and a rise later (to 8.1% at 6 h and at 8 h intervals), but the changes in frequency did not reach a significant level. Results are compared with those obtained in similar recent experiments by Leonard and Deknudt (500 R total exposure) in which an initial decrease in yield was also found, but with more pronounced fluctuations in frequency later. The relative importance of radiation-induced changes in the spermatogonial population and of decreased oppurtunities for interaction of lesions on fractionation is discussed with reference to the observed effects.

The effect of dose-rate on the induction of reciprocal translocations in mouse A type spematogonia by 600 RX- and γ-irradiation was studied by scoring multivalent configurations in descendant spermatocytes. With X-irradiation over a range of dose-rates from 0.8 to 913 R/min there was no significant change in the frequency of affected spermatocytes, which averaged 12.8%. With γ-irradiation, however, there was a steady increase in frequency from 1.4% at 0.02 R/min to 12.1% at 86 R/min, the points fitting a straight line on a semi-log plot. At 0.08 R/min the X-ray yield was twice that for γ-rays. Possible reasons for these differences are discussed. Frequencies of 0, 1, 2 translocations per spermatocyte did not fit a Poisson distribution since there were less then expected in the 1-class, but more in higher classes. This was probably a consequence of differential radiosensitivity of the irradiated spermatogonia, although preferential clonal proliferation may also be involved.

Translocation frequencies were studied in mouse spermatocytes derived from X-irradiated spermatogonia. Over the range from 50–800 R the dose-response relationship did not differ significantly from linearity, in agreement with previous findings of Leonard and Deknudt . It seems probable that the initial dose-response curve has the expected square-law component but becomes destorted by secondary factors between irradiation and meiotic examination of cells. Observed translocation frequencies were little affected by increasing length of time (from 11–30 weeks) between irradiation and examination, except for a possible decline at the highest dose (800 R). No significant frequency differences were found between mated and solitary males, or between those given whole-body or part-body (gonadal) irradiation.

The problem addressed in this report is the determination of a quantitative estimate of a resource from estimates of fundamental variables which describe the resource. Due to uncertainty about the estimates, these basic variables are stochastic. The evaluation of random equations involving these variables is the core of the analysis process. The basic variables are originally described in terms of a low and a high percentile (the 5th and 95th, for example) and a central value (the mode, mean or median). The variable thus described is then generally assumed to be represented by a three-parameter lognormal distribution. Expressions involving these variables are evaluated by computing the first four central moments of the random functions (which are usually products and sums of variables). Stochastic independence is discussed. From the final set of moments a Pearson distribution is obtained; the high values of skewness and kurtosis resulting from uranium data requires obtaining Pearson curves beyond those described in published tables. A cubic spline solution to the Pearson differential equation accomplishes this task. A sample problem is used to illustrate the application of the process; sensitivity to the estimated values of the basic variables is discussed. Appendices contain details of the methods andmore » descriptions of computer programs.« less

A computer program was developed to extend the APT (Automatic Programmed Tool) System to non-Cartesian axial movements. Points are calculated on composite curves, consisting of joined segments of lines, conics, or spline curves, such that a certain parametrically defined curve between the points approximates the composite curve within a prescribed tolerance. The parametric curve used is one that describes the tool movement on a machine with non-Cartesian axes. 90 figures.

Publisher Summary This chapter describes the selection pressure in mammalian cell populations. Mammalian cells offer a limited population genetics of their own, analogous to the population genetics of sexually reproducing organisms, though obviously less complex. The frequency of hyperdiploidy may be of the order of one in 1000 and the frequency of structural rearrangement is much lower. The frequency of hypodiploidy cannot be objectively estimated at all because of confusion with spuriously low counts resulting from cell breakage. An approach that could demonstrate a proliferative differential between normal cells and aneuploid cells is offered by the occurrence of karyotypic mosaics in man.