Thin film deposition for permeability increase of gas being implanted (theoretical consideration)

A theoretical model has been developed for diffusive permeation of gas injected by ion bombardment through thin metallic targets, including membranes with thin films deposited onto the surface. The film material differs from the substrate material. Calculations for gas atom distribution in the film and substrate have been carried out, as well as gas fluxes to the source and sink sides in such a system in a quasi-stationary régime. The possibility of a permeability increase is revealed under implantation of gas ions both with low (～ keV) and higher energies (of the order of tens of keV) by deposition onto an irradiated target surface having a film of material with a lower diffusion coefficient for the gas being implanted than the substrate material itself. It has been shown that the most significant effect may be obtained under relatively high energy implantation for deposited film thicknesses markedly less than the mean ion range, and where the film permeability (diffusion coefficient and/or gas solubility) is much smaller than that of the substrate material itself. Periodic or simultaneous with implantation film renewal on the target surface has been suggested to compensate for sputtering.     

UDP-glucose:solasodine glucosyltransferase from eggplant (Solanum melongena L.) leaves: partial purification and characterization

The purpose of the present study was to evaluate the healing pattern of an experimentally induced osteotomy in Hartley guinea pigs in the presence of static magnetic and pulsed electromagnetic fields. The sample consisted of 30 Hartley guinea pigs 2 weeks of age divided into 3 groups: pulsed electromagnetic, static magnetic, and control. An osteotomy was performed in the mandibular postgonial area in all groups under general anesthesia. During the experimental period of 9 days, the animals were kept in experiment cages 8 hours per day, the first two groups being in the presence of pulsed electromagnetic and static magnetic field, respectively. Based on histologic results, both static and pulsed electromagnetic fields seemed to accelerate the rate of bone repair when compared to the control group. The osteotomy sites in the control animals consisted of connective tissue, while new bone had filled the osteotomy areas in both magnetic field groups.     

Hepatitis B surface antigen carrier state in hepatosplenic schistosomiasis

The prevalence of hepatitis B surface antigen (HBsAg) was studied in 103 cases of hepatosplenic schistosomiasis (HSS), 134 control cases with a variety of illnesses including hepatointestinal schistosomiasis, and 600 blood donors, in an area endemic for both schisfosomiasis and viral hepatitis. The patients with HSS proved to be persistent carriers for HBsAg in a significantly higher proportion than the other two groups of cases. The HSS cases who were carriers of HBsAg had more clinical signs of chronic liver disease and strikingly more chronic inflammation of the portal spaces on liver biopsy. It is suggested that abnormal immunological responses in patients with HSS makes them more susceptible to become carriers of HBsAg and that the addition of this injurious factor makes their basic disease worse, and may be responsible for the development of cirrhosis in some cases.     

Formation of stable shifts of systemic arterial pressure in controlled experiments with feedback

Calcitonin is a peptide hormone secreted by C-cells which, in humans, are found mainly in the thyroid gland. It now seems that a major physiological function of this hormone in man is the long-term maintenance of the skeleton achieved by control of bone resorption. A marked sex difference in circulating calcitonin levels normally exists, with a relative deficiency in women as compared to men. It has now been found that oestrogens regulate calcitonin secretion and it appears likely that the loss of ovarian function at the menopause accelerates the natural decline in calcitonin secretion which occurs with age. Thus, post-menopausal women are more markedly calcitonin-deficient. Levels of the bone-resorbing hormones, parathyroid hormone (PTH) and 1,25 dihydroxyvitamin D are not elevated post-menopausally and it seems likely that the increased bone resorption which leads to post-menopausal bone loss is due mainly to the loss of oestrogen and calcitonin secretion.