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The magnetic entropy change [Δ S M ( T , H )] around the phase transition temperature T C is investigated by the scaling method for Fe 0.5 Co 0.5 Si, which exhibits a Skyrmion phase below T C . The parameters of Δ S M ( T , H ) exhibit field dependent behaviors. The Δ S M ( T , H ) curves under high field can be well scaled into a single universal curve independent of external field and temperature. However, Δ S M ( T , H ) curves under low field become divergent just below T C , which indicates a characteristic of first-order transition. The scaling investigation of Δ S M ( T , H ) curves indicates that the phase transition in Fe 0.5 Co 0.5 Si is of a weak first-order type in low field region, while it is driven into a second-order one under high field. This weak first-order phase transition in low field region resembles that in typical skyrmion system MnSi which is caused by the critical fluctuation. The result suggests that critical fluctuation plays an important role in the phase transition and formation of skyrmion state. [ABSTRACT FROM AUTHOR]

Abstract: Powdered Fe2O3 –Fe2(MoO4)3 with different amounts of iron and molybdate precursors was prepared by a solvothermal route, followed by a supercritical drying and oxidation at 500°C. The possibility to arrange Fe or Mo precursors in excess into a methanol solution makes one accessible to the preparation of iron(III) molybdate samples with different composition. The structural parameters and relationship between different phases in the composition are obtained from Rietveld profile refinement. Our intention was to modify the magnetic properties of Fe2(MoO4)3 by adding the crystalline phase of Fe2O3, which carries a Fe–O magnetic component. A possible contribution to the magnetization and the magnetic susceptibility by this magnetic component is analyzed in the temperature range 2–300K. The observed higher magnetic susceptibilities are compared to those reported. [Copyright &y& Elsevier]

Abstract: The aim of the present study was to analyze the relation of low or high serum thyrotropin (TSH) with mortality in patients with invasively treated coronary artery disease. We followed-up 942 patients who underwent coronary angioplasties or coronary artery bypass graft surgery over a mean follow-up period of 6.4±1.6 years. The study population was divided into three groups using the reference limits of serum TSH (0.25–2.12 mIU/l) as cut-offs. There were 118 patients (12.5%) with low and 125 patients (13.3%) with high serum TSH. One hundred and seventy-four subjects (18.5%) deceased during follow-up. Multivariable analyses revealed that both subjects with low and high serum TSH had a lower all-cause and circulatory mortality than subjects with serum TSH within the reference range. We conclude that low and high serum TSH levels are associated with a reduced all-cause and circulatory mortality in patients with coronary artery disease. [Copyright &y& Elsevier]

Electromagnetic properties of complex oxide solid solutions containing Ce and Y attract increasing interests due to their high application potential. Their properties are known to be dependent on many factors including grain size and crystal defects. Here we focus on unique features of nanocrystalline Ce 1-x Y x O 2-δ (x ≤ 0.3) solid solutions prepared via a mechanosynthesis. Mechanically activated CeO 2-δ and mechanosynthesized Ce 1-x Y x O 2-δ exhibit room-temperature ferromagnetism. The saturation magnetization reaches maximum for the Ce 0.9 Y 0.1 O 2-δ solid solution. XPS and Raman spectra show that Ce4+ ions are partially reduced to Ce3+, with simultaneous introduction of oxygen vacancies accumulated on surface of the solid solutions. An analysis of the experimental magnetization data and the determination of both the spin state and the concentration of magnetic carriers revealed that a small part of the Ce3+ spins (<1%) is responsible for the magnetic state of the Ce 1-x Y x O 2-δ system. Existence of clusters with a short-range antiferromagnetic order is also suspected. Image 1 • Mechanosynthesized Ce 1-x Y x O 2-δ solid solutions exhibit room temperature ferromagnetism. • Experimental magnetization curves are described by the Brillouin function. • Free Ce3+ magnetic carriers possess low concentration. • Antiferromagnetic short-range interaction between Ce3+ carriers is also observed. [ABSTRACT FROM AUTHOR]

Abstract: Aims: We undertook this prospective observational study to investigate the long-term prognosis after balloon angioplasty (PTCA), coronary stenting (CS) and coronary artery bypass grafting (CABG). Methods and results: A total number of 1038 patients with PTCA (n =499), CS (n =294) or CABG (n =245) were followed-up over a mean time of 6.4±1.8 years. Forty-two patients (4.0%) were lost to follow-up, leaving a study population of 996 subjects who were available for analyses. The primary and secondary endpoints were mortality and major adverse cardiac events (MACE), respectively. Overall death rate was 19.3%. Age, pulse pressure, smoking, diabetes, serum LDL cholesterol levels and left ventricular ejection fraction rather than the intervention type independently predicted mortality. The incidence rate of MACE was 53.7%. Compared to PTCA patients, CS patients had lower (hazard ratio 0.693; 95% confidence interval 0.514–0.793) and CABG patients the lowest risk of MACE (hazard ratio 0.343; 95% confidence interval 0.261–0.450). Further risk factors for MACE were serum LDL cholesterol levels, three-vessel coronary artery disease and left ventricular ejection fraction of <30%. Conclusion: Long-term mortality does not differ among patients who received percutaneous interventions or CABG. Major adverse cardiac events occur more often in patients with previous percutaneous interventions, whereby CS has advantage over PTCA. [Copyright &y& Elsevier]