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Raman spectroscopy is an efficient technique for studying the evolution of microstructure of materials under irradiation. For that purpose, a Raman spectrometer has been recently installed at the JANNUS-Saclay platform. In this paper, we describe the new setup for in situ experiments. These in situ experiments allowed following the microstructural evolution of different materials (SiC, ZrO2 and B4C) as a function of ion fluence on a single sample (either single crystal or polycrystalline ceramics) under the same irradiation conditions. Our results show that Raman spectroscopy is a versatile non-contact technique for studying on-line crystalline phase changes or amorphization of irradiated iono-covalent solids. A detailed analysis of Raman spectra is provided for the three materials (SiC, ZrO2 and B4C) investigated in this study, revealing quite different behaviors upon irradiation. Basically, Raman spectroscopy gives insight on these evolutions at the level of bonds given by specific phonon modes, in good agreement with Rutherford backscattering channeling (RBS/C), X-ray diffraction (XRD) or transmission electron microscopy (TEM) data, which provide information at a long-range scale. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

It is well-known that the azido bridge gives rise antiferromagnetic (AF) or ferromagnetic (F) coupling depending on its coordination mode, namely end-to-end or end-on, respectively. The aim of the present work is to analyse the factors contributing to this different magnetic behaviour. The difference dedicated configuration interaction (DDCI) method is applied to several binuclear Cu(II) azido-bridged models with both types of coordination. In end-on complexes, the direct exchange and the spin polarisation contributions are found to be responsible for the ferromagnetic coupling. In end-to-end complexes, both the direct exchange and the spin polarisation are small and the leading term is the antiferromagnetic dynamical polarisation contribution. The most relevant physical effects are included in the DDCI calculations so that good quantitative agreement is reached for the coupling constant as well as the spin densities.

The authors followed up certain changes occurring at the level of the hypophysis-adrenal axis, during the development of experimental ulcers induced by pylorus ligature in rats treated with negative air ions. Previous experiments have shown that negative aeroionotherapy had a favourable influence on the prevention and evolution of gastric ulcers. The results of the present experiment showed that, under the influence of aeroionotherapy, the number of gastric ulcers/animal, and the relative weight of the adenohypophysis and of the adrenals glands decreased; the width of the fascicular zone of the adrenal cortex, and the volume of the cell nuclei in this fascicular zone also decreased.

A survey of the Compositae used in traditional medicine and as economic plants by Paraguayan country people was undertaken to identify the components of crude drugs traded by herbalists. Forty-five medicinal and economic species have been identified through field work in the rural areas and enquiries in the markets, as well as by examination of the literature in the Spanish language. Some crude drugs are shown to be mixtures of several closely-related species. The role of indigenous plant remedies within the local health care system is also discussed.

Samples of the sweet-tasting species Acanthospermum hispidum DC. (Compositae) (aerial parts), Boscia salicifolia Oliv. (Capparidaceae) (stem bark), Hovenia dulcis Thunb. (Rhamnaceae) (peduncles) and Inga spectabilis Willd. (Leguminosae) (arils) were acquired as part of a continuing search for high-intensity natural sweeteners of plant origin. Following their preliminary safety evaluation, the sweetness of these plants was traced to large amounts of sugars and polyols by taste-guided fractionation, which were identified and quantified using gas chromatography/mass spectrometry. The combined yields of sugars and polyols in the A. hispidum, B. salicifolia, H. dulcis, and I. spectabilis samples investigated were 6.9, 10.1, 18.4 and 12.1% w/w, respectively. These yields are much higher than the total saccharide and polyol content (2.4% w/w) of the sweet dried fruits of Thladiantha grosvenorii (Swingle) C. Jeffrey (Cucurbitaceae), a species which has previously been reported to contain more than 1% w/w of the intensely sweet triterpene, mogroside V. The dried leaves of Symplocos tinctoria (L.) L'Hérit. (Symplocaceae), which were not appreciably sweet, were found to contain only 2.0% w/w of sugars. The results of this investigation, therefore, suggest that unless the saccharide and/or polyol content of a plant part is well over 5% w/w, then it is unlikely to exhibit an overtly sweet taste, unless an intense sweetener is present.

Thirty-six healthy albino rats were divided into three groups and the histologic structure of the testes was examined after treatment: group 'C'--10 healthy control rats were untreated; group 'Pb'--eight rats received intraperitoneal injections of 8.5 mg per kg body weight lead acetate for 154 days (15 doses in all); group 'PbA'--eight rats intoxicated with lead, like group 'Pb' but which, during the last 21 days before killing, were treated with 5 ml per kg body weight per day of a 2% injectable solution of sodium aspartate. As compared with the controls, group 'Pb' showed alteration of the histopathologic pattern and reduction in the size of seminiferous tubules, basal membrane separation and a decrease in the cell content of the germinal layer, lesions of the spermatocytes and spermatids, and slight oedematous dissociation in the interstice. In 75% of the group 'PbA' animals, normal aspects similar to those of group 'C' were found.

The authors studied the influence of negative aeroionotherapy (AIT) on the gastric ulcer induced by pylorus ligature. After 24 hours the ligature was removed and the stomach was studied with respect to number and aspect of ulcers (hemorrhagic or not), periulcerous mucosa (edema, folds), acidity and microhemorrhage of gastric secretion. The animals were divided into 4 groups: C1 and C2 (controls)--not treated with air ions; P--prophylactically exposed 10 days before the operation to AIT; T--submitted to AIT prophylactically 10 days before the operation--therapeutically 5 days after operation. The results showed a favourable influence of AIT: the number of gastric ulcers was smaller; the regeneration processes in the mucosa were ameliorated; the gastric acid secretion and microhemorrhage diminished.

The problem of the inactivation of DDT deposits on dry mud surfaces is presented and its causes outlined. The phenomenon is found to be due to adsorption of the DDT crystals present on the surface; this adsorption appears to be the initial step in the catalytic decomposition of DDT by the iron oxides present in soils, since there is a direct relation between the amount of oxides present and their capacity to inactivate DDT deposits.The DDT-inactivating capacity of soils can be determined by testing them for catalytic activity in the thermal decomposition of DDT.The adsorption of DDT by soil is influenced by environmental relative humidity. Inactivated deposits may be reactivated by increase of the atmospheric humidity.Several substances proposed for the protection of the DDT deposit from inactivation were tested without success. Reference is made, however, to the encouraging findings of some other workers. Limewashing is recommended for the protection of DDT deposits.