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This paper describes the results obtained from a simulation study of electric utility system expansion with various amnounts of nuclear generation in large units. Estimates of capital costs, fuel costs, and operation and maintenance costs are used for closed-cycle water plants from 600 to 1,000 mw (megawatts). The economic applications of specefic plants are studied in terms of present worth of all future revenue requirements. Additional studies investigate the effect of varying nuclear unit availability, fossil-fuel escalation assumptions, and nuclear fuel prices.

Swiss mice were intranasally infected with influenza A2 virus and treated with urethan in order to detect whether the joint action of the two agents would enhance the development of lung tumors. The average number per mouse of the typical lesions induced by the two treatments together with their location, their histological and histochemical characteristics and the percentage of death in the different groups of animals were recorded. Results indicated that 51.7 % of the mice infected with influenza virus and treated with urethan had both bronchial dysplastic lesions due to influenza virus, and tumors induced by urethan. In this group the number of tumors was smaller than in the mice treated with the carcinogen only and no invasive pulmonary carcinomas were observed. The dysplastic lesions caused by influenza A2 virus as well as the lung adenomas induced by urethan maintained their typical histological and histochemical characteristics even when occurring in a close position. The failure of urethan to enhance the induction of lung tumors in mice exposed to influenzal infection might be ascribed to the different primary sites of response of the pulmonary tissue to the two agents, i.e. the bronchial epithelium for influenza virus and the alveolar epithelium for urethan.

The method to be described is particularly suitable for the quantitative determination of zinc, present in the form of zinc oxide or of zinc salts, in transparent rubber articles. Rubber articles of this type contain very small quantities of zinc compared with the quantities present in non-transparent rubber articles, in fact the lower limit is only 0.05 per cent, i.e., only about one-hundredth as much as the normal content. The analytic determination of the zinc content when present in such extremely low percentages as this is extremely difficult by ordinary, methods, and even with higher but nevertheless small percentages of zinc, the use of relatively large quantities of material is necessary and the analytical results are often far from precise. The ordinary method of incineration in a porcelain crucible does not lend itself to the isolation of small quantities of zinc because the latter is easily fixed by the silica of the crucible. On the other hand incineration in a platinum crucible is not suitable because of the tendency of this metal to form a carbide in contact with the carbonaceous substances in the rubber. The novel feature of the method of analysis to be described is the procedure for obtaining a solution of the inorganic substances in the rubber. This involves destruction of the rubber by concentrated sulfuric acid and subsequent oxidation of the organic residue by concentrated nitric acid. This gives a solution of the zinc in the form of sulfate. It is then isolated as zinc sulfide and is redissolved and determined volumetrically by the already known method of precipitation with a standard solution of potassium ferrocyanide. The most suitable concentration, acidity and temperature to give precise results by this procedure for low percentages of zinc in rubber were established.

Lymphoid cells obtained from spleen and lymphnodes of mice in which the sarcoma induced by the Murine Sarcoma Virus-Moloney (MSV-M) has regressed (MSV-M regressors) inhibit MSV-M oncogenesis and induce MSV-M tumor regression in mice in which, because of immunodepressive treatments, the tumor would grow until the mice died (progressors). On the other hand, MSV-M was detected in the spleen of MSV-M infected mice, immediately after the infection or later on both in regressors and progressors. These data suggest that immune lymphoid cells from MSV-M regressors carry MSV-M. Immune lymphoid cells harvested 24 days after the infection from BALB/c MSV-M regressors were therefore injected i.p. into syngeneic mice. In three separate experiments, 26/33 injected mice died (from 40 to 102 days after the injection); tumors were present in 92 % of the examined mice. These tumors were found in various sites, and were histologically similar to the MSV-M induced rhabdomyosarcoma. Sarcoma virus was recovered from immune lymphoid cell extracts, and from the tumors induced in vivo by immune lymphoid cells. The virus isolated is capable of inducing sarcomas in mice and foci of cell transformation on mouse embryo cell cultures.

Vom morphologischen Bild der P. M. sind schon verschiedene Varietaten beschrieben. Zu den in der Literatur erwahnten berichtet der Verfasser uber einen Fall, in dem neben ganz typischen Herden sehr mannigfaltige Formen hochgradiger Hyperkeratose vorhanden waren bis zur Bildung von Anhaufungen vom Charakter masiger Hauthorner. Das histologische und histochemische Studium zahlreicher Biopsien gestattet den Schlus, das auf der Basis aller dieser verschiedenen Formen immer die klassischen Lasionen der P. M. vorhanden sind.

SummaryA study was made of the effects of diets supplemented with psyllium hydro-colloid (Metamucil) on bile acid half-lives and pool sizes in normal and hypophysectomized rats. Metamucil decreased bile acid half-lives by about 40% in both normal and hypophysectomized rats. The mucilloid also effected small but significant increases in the size of the bile acid pools. It was demonstrated that Metamucil increases bile acid excretion in rats by increasing the turnover rate and size of the bile acid pool. Pituitary and target gland hormones have little or no effect on the drug's ability to effect these changes.

Adeno-associated satellite virus type 4 interferes with the replication of its helper adenovirus. No interferon-like soluble substance could be detected in satellite-infected cultures and other DNA- and RNA-containing viruses were not inhibited by coinfection with satellite virus under conditions which reduced adenovirus yields by more than 90% in monkey cells. Altering the concentration of adenovirus in the presence of constant amounts of satellite resulted in a constant degree of interference over a wide range of adenovirus inocula and suggested that adenovirus concentration was not a significant factor in the observed interference. The interference with adenovirus replication was abolished by pretreating satellite preparations with specific antiserum, ultraviolet light or heating at 80°C for 30 min. This suggested that infectious satellite virus mediated the interference. Satellite virus concentration was found to be a determinant of interference and studies indicated that the amount of interference with adenovirus was directly proportional to the concentration of satellite virus. 8 hr after adenovirus infection, the replication of adenovirus was no longer sensitive to satellite interference. This was true even though the satellite virus was enhanced as effectively as if the cells were infected simultaneously with both viruses. Interference with adenovirus infectivity was accompanied by reduced yields of complement-fixing antigen and of virus particles which suggested that satellite virus interfered with the formation and not the function of adenovirus products. When cells were infected either with adenovirus alone or with adenovirus plus satellite, the same proportion of cells plated as adenovirus infectious centers. However, the number of plaque-forming units of adenovirus formed per cell in the satellite-infected cultures was reduced by approximately 90%, the same magnitude of reduction noted in whole cultures coinfected with satellite and adenovirus. This suggested that all cells infected with the two viruses were producing a reduced quantity of adenovirus.

The effects of accumulated tissue cholesterol concentrations on bile acid half-lives, pool sizes and excretion rates were studied in normal and hypophysectomized rats, and hamsters. High tissue cholesterol concentrations caused decreased bile acid half-lives in both normal and hypophysectomized rats. Total bile acid pool sizes remained static in both types of rats. In normal rats, there was a decrease in the cholic acid and a compensating increase in the chenodeoxycholic acid pool size. No change was observed in hypophysectomized rat pool spectra. Bile acid synthesis rates increased in both hypophysectomized and normal rats in response to elevated tissue cholesterol. Hamster bile acid net synthesis was unchanged by accumulated cholesterol, because an increase in the cholic acid half-life was compensated for by an increase in cholic acid pool size, and the chenodeoxycholic half-life and pool size were static. The relationship of these findings to comparative rates of tissue cholesterol accumulation in the three animals fed diets supplemented with cholesterol is discussed.

Several anion-exchange polymers, with different skeletal and functional group structure, were studied to determine their relative effectiveness in sequestering bile acids in both in vitro and in vivo systems. In the in vitro systems neither the structure of the functional groups, nor their p K a , or skeletal structure, appeared to have any effect on sequestering ability of the polymer. In rat in vivo systems, skeletal structure was of major importance. Polymers with cellulose skeletons were ineffective. Two anion-exchange resins, amberlite XE-268P and amberlyst A-26, proved to be highly effective bile acid sequestrants in both in vivo and in vitro systems.

The rate of reaction of Ni(II) ion and acetylacetone to form monoacetylacetonate nickel(II) ion was studied conductometrically by a stop-flow method. The solvents consisted of several mixtures of water in 2-propanol ranging from 9·85 to 14·45 per cent water by weight. The temperatures in this study were 8·96°C, 0·00°C and −10·25°C. The rate of formation of the monoacetylacetonate nickel(II) ion was found to be first order with respect to both nickel ion concentration and the concentration of the enol tautomer of acetylacetone, hence second order overall. Hydrogen ion initially present in concentration up to 5 × 10−4 M had no apparent effect on the initial rate of reaction. The initial rate was also shown to be independent of the ionic strenght. In all solvents employed, the rate of first complex formation was complicated from the outset of reaction by the reversible nature of the process. Small changes in the dielectric constant of the solvent system were seen to have a large effect on the rate of formation of the complex. The log of the second order rate constant was found to be a linear function of 1 D in the range of dielectric constant of 33−22. Below this range, the plot shows a very rapidly increasing slope attributable to changes in the co-ordination sphere of Ni(II). The energy of activation in any solvent of fixed composition, (Ea)c, was mathematically separated into two components, energy of activation at constant dielectric, (Ea)D, and energy of activation at constant temperature, (Ea)T. The relationship: (Ea)C = (Ea)T + (Ea)D appears to hold at dielectric constant above 25.

SummaryThe effects of cholesterol feeding and accumulated tissue cholesterol on bile acid metabolism in normal female rats were studied. Feeding diets supplemented with cholesterol and corn oil over the entire experimental period resulted in decreases in the cholic and chenodeoxycholic acid pool half-lives of 1.6 and 0.9 days, respectively. In experiments on rats with accumulated tissue cholesterol fed unsupplemented basal rations during the experimental period, the half-lives of these acids also decreased 1.6 and 0.9 days, respectively, from the values for normal control rats. In both the dietary and accumulated tissue cholesterol experiments, the total bile acid pool concentration was unchanged but there was an important decrease in cholic acid concentration accompanied by a compensating increase in chenodeoxycholic concentration. Studies in the animals with elevated tissue cholesterol showed that the effects on bile acid turnover were not due to increased levels of sterols in the gastrointestinal tract...

It is shown that if {y n} is a block of type I of a symmetric basis {x n} in a Banach spaceX, then {y n} is equivalent to {x n} if and only if the closed linear span [y n] of {y n} is complemented inX. The result is used to study the symmetric basic sequences of the dual space of a Lorentz sequence spaced(a, p). Let {x n,f n} be the unit vector basis ofd(a, p), for 1≤p

This paper describes the development of dynamic power system equivalents for use in stability studies of interconnected systems. The problem of electromechanical equivalencing is formulated, and a method of constructing electromechanical equivalents is described. The performance of these equivalents has been evaluated by a series of computational tests. Theoretical material pertaining to electromechanical equivalencing is presented in a companion paper.

Anfuhrung der einschlagigen Kasuistik und der verschiedenen Meinungen uber die vonBloch besonders hervorgehobene Gruppe der „benignen, nichtnavogenen Epitheliome“. Beschreibung eines typischen Falles, entsprechend der ersten der vonBloch unterschiedenen Untergruppen, charakterisiert durch das histologische Bild des intermediaren Epithelioms mit auserordentlich starker Melaninpigmentierung und sehr zahlreichen dendritischen Zellen im Blastomgewebe.