Landau diamagnetism of a weakly bound muonium atom

The ionization with temperature of weakly bound muonium atoms in undoped CdS has been studied using the technique of muon spin relaxation in a transverse magnetic field of 10 mT. For this atom the Coulomb binding energy between the muon and the electron is sufficiently small that the Landau diamagnetic term determines the magnetic behavior of the system: due to the diamagnetic interaction the muon precession in a transverse magnetic field exhibits a frequency shift of approximately 0.5% around the ionization temperature.http://www.sciencedirect.com/science/article/B6TVM-448FTXD-1/1/e6a2420c40c0e5e534a3e5d0f052d41

Study of the magnetic penetration depth in RbOs_2O_6

Measurements of the magnetic field penetration depth \lambda in the pyrochlore superconductor RbOs_2O_6 (T_c\simeq6.3 K) were carried out by means of the muon-spin-rotation (\muSR) technique. At low temperatures \lambda^{-2}(T) saturates and becomes constant below T\simeq 0.2T_c, in agreement with what is expected for weak-coupled s-wave BCS superconductors. The value of \lambda at T=0 was found to be in the range of 250 nm to 300 nm. \muSR and equilibrium magnetization measurements both reveal that at low temperatures $\lambda$ is almost (at the level of 10%) independent of the applied magnetic field. This result suggests that the superconducting energy gap in RbOs_2O_6 is isotropic.Comment: 8 pages, 9 figure

Magnetism, superconductivity and coupling in cuprate heterostructures probed by low-energy muon-spin rotation

We present a low-energy muon-spin-rotation study of the magnetic and superconducting properties of YBa2Cu3O7/PrBa2Cu3O7 trilayer and bilayer heterostructures. By determining the magnetic-field profiles throughout these structures we show that a finite superfluid density can be induced in otherwise semiconducting PrBa2Cu3O7 layers when juxtaposed to YBa2Cu3O7 "electrodes" while the intrinsic antiferromagnetic order is unaffected.Comment: 10 pages, 9 figures; figure 9 corrected in version

RESEARCH OF IRON SULFATE HEAT TREATMENT IN PRESENCE OF ALKALINE REAGENTS AND WATER

The results of the research of the composition and properties of products formed during the heat treatment of the iron sulfate in the in the presence of alkaline reagents (CaO and Na2CO3) and H2O are presented. It is shown, that the formation of α-Fe2O3 using CaO and H2O occurs at a temperature 600–650°С, Na2CO3 and H2O at a temperature 350–450°С. Products of heat treatment have pigment properties: saturated color, spreading capacity 10–12 g/m2, oil absorption 30–40 g/100 g

High Mutability of the Tumor Suppressor Genes RASSF1 and RBSP3 (CTDSPL) in Cancer

BACKGROUND:Many different genetic alterations are observed in cancer cells. Individual cancer genes display point mutations such as base changes, insertions and deletions that initiate and promote cancer growth and spread. Somatic hypermutation is a powerful mechanism for generation of different mutations. It was shown previously that somatic hypermutability of proto-oncogenes can induce development of lymphomas. METHODOLOGY/PRINCIPAL FINDINGS:We found an exceptionally high incidence of single-base mutations in the tumor suppressor genes RASSF1 and RBSP3 (CTDSPL) both located in 3p21.3 regions, LUCA and AP20 respectively. These regions contain clusters of tumor suppressor genes involved in multiple cancer types such as lung, kidney, breast, cervical, head and neck, nasopharyngeal, prostate and other carcinomas. Altogether in 144 sequenced RASSF1A clones (exons 1-2), 129 mutations were detected (mutation frequency, MF = 0.23 per 100 bp) and in 98 clones of exons 3-5 we found 146 mutations (MF = 0.29). In 85 sequenced RBSP3 clones, 89 mutations were found (MF = 0.10). The mutations were not cytidine-specific, as would be expected from alterations generated by AID/APOBEC family enzymes, and appeared de novo during cell proliferation. They diminished the ability of corresponding transgenes to suppress cell and tumor growth implying a loss of function. These high levels of somatic mutations were found both in cancer biopsies and cancer cell lines. CONCLUSIONS/SIGNIFICANCE:This is the first report of high frequencies of somatic mutations in RASSF1 and RBSP3 in different cancers suggesting it may underlay the mutator phenotype of cancer. Somatic hypermutations in tumor suppressor genes involved in major human malignancies offer a novel insight in cancer development, progression and spread