The magnetic structureof a55mol% Fe0-46 molyo P,O, semiconducting glass containing various relative concentrations of FeS+ and Fez+ has been studied by ESR techniques over the temperature range -190 to 300 "C. It was determined that the iron ions in the glass matrix are antiferromagnetically coupled in FeS+-Fe2+ ion pairs. The isolated Fe3+ ions were found to be in orthorhombic crystalline fields with 1 = 1/3 and 0.23 < D < 0.8 cm-l, where D and 1 are constants in the spin Hamiltonian. Heat treatment of the glass samples caused precipitation of Fes+-rich crystalline phases, and it was determined that the Fe*+ ions in these phases were antiferromagnetically aligned.

The ac and dc characteristics of 55 mol% Fe0-45 mol% P105 glass were measured as functions of time of heat treatment at 600" and of the ratio Fe3i/Feto+nl. The dc resistivity behavior a t constant temperature (for bulk spscimens) was correlated with the appearance and growth of crystals in a glassy matrix, as indicated by data obtained with a GuinierDe Wolff X-ray camera. Dispersions appeared in plots of tan S, , vs frequency; a hypothesis explaining the appearance of these peaks is presented.

The isothermal aging-microstructure-magnetic property relationship of a SmCo 2:17 alloy was investigated in the present study. The alloy also contained Fe, Cu and Zr as major addition. Its magnetic properties, including intrinsic coecivity H ci , remanence B r and maximum energy product (BH) max, were obtained from the measured second quadrant M-H hysteresis curves. The microstructure of the alloy was characterised using X-ray diffraction (XRD) and TEM. It was found that, as the one step aging temperature was increased from 850 to 900uC, the remanence of the SmCo 2:17 alloy magnet was increased while its coercivity was reduced. The maximum energy product (HB) max of the magnet was significantly improved by applying a two step aging, consisting of aging first at 900uC followed by aging at 850uC. Based on XRD and TEM analyses, effects of the aging condition on the microstructure and magnetic properties were discussed. The microstructural change observed in the current work included cell size of the cellular structure and the degree of Cu segregation at the cell boundaries. Change in the degree of Cu segregation at the cell boundaries might be the major cause for the change in coercivity of the alloy aged in different aging conditions. The effect of aging condition on the remanence could be attributed to the effect of aging condition on cell size of the cellular structure, which affects the volume fraction of SmCo 2:17 phase in the alloy.

Interleukin-4 (IL-4), a cytokine produced mainly by immune cells, may promote cancer cell survival by mediating apoptosis resistance in epithelial tumors. The IL-4 Receptor (IL-4R) is overexpressed in a variety of human solid cancer cell lines and primary cell lines, and may be a promising target for anti-tumor therapy. Here, we show that loss of IL-4Rα, a component of the IL-4 receptor, in two murine mammary tumor cell lines (R221A and 4T1), reduces tumor cell survival and results in attenuated metastatic growth in secondary sites. Proliferation and direct cell counting analyses, following knockdown of IL-4Rα with RNA interference, show that R221A clones with reduced IL-4Rα expression proliferate at a comparable rate to control clones, but the number of cells is significantly reduced. This data correlates with the finding that reduced IL-4Rα expression in R221A cells almost completely abolishes tumor take after orthotopic mammary injection in vivo. Furthermore, reduced IL-4Rα expression in R221A and 4T1 cell lines results in a decrease [2.4 fold] in lung metastatic growth in vivo. Reduced expression of IL-4Rα in 4T1 cells results in a similar decrease of liver metastasis. In support of this data, proliferation assays following serum starvation and a modified clonogenic survival assay show that both 4T1 and R221A knockdown clones have a decrease [2 fold] in survival ability in comparison to control clones. Taken together, our results indicate that the IL-4 receptor promotes survival of breast cancer cells at metastatic sites, and suggests that drugs targeting this pathway, currently in clinical trials for respiratory ailments, may have potential for limiting metastatic disease. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5328. doi:1538-7445.AM2012-5328