Strain-driven elastic and orbital-ordering effects on thickness-dependent properties of manganite thin films

We report on the structural and magnetic characterization of (110) and (001) La2/3Ca1/3MnO3 (LCMO) epitaxial thin films simultaneously grown on (110) and (001)SrTiO3 substrates, with thicknesses t varying between 8 nm and 150 nm. It is found that while the in-plane interplanar distances of the (001) films are strongly clamped to those of the substrate and the films remain strained up to well above t=100 nm, the (110) films relax much earlier. Accurate determination of the in-plane and out-of-plane interplanar distances has allowed concluding that in all cases the unit cell volume of the manganite reduces gradually when increasing thickness, approaching the bulk value. It is observed that the magnetic properties (Curie temperature and saturation magnetization) of the (110) films are significantly improved compared to those of (001) films. These observations, combined with 55Mn-nuclear magnetic resonance data and X-ray photoemission spectroscopy, signal that the depression of the magnetic properties of the more strained (001)LCMO films is not caused by an elastic deformation of the perovskite lattice but rather due to the electronic and chemical phase separation caused by the substrate-induced strain. On the contrary, the thickness dependence of the magnetic properties of the less strained (110)LCMO films are simply described by the elastic deformation of the manganite lattice. We will argue that the different behavior of (001) and (110)LCMO films is a consequence of the dissimilar electronic structure of these interfaces.Comment: 16 pages, 15 figure

Inhomogeneous structure and magnetic properties of granular Co10Cu90 alloys

Granular Co10Cu90 alloys displaying giant magnetoresistance have been obtained by melt spinning followed by an appropriate heat treatment in the range 0-700 degreesC. Their structural and magnetic properties have been studied on a microscopic scale using Co-59 NMR technique and thermoremanent magnetization measurements. The study reveals that in the as-quenched samples Co is involved in two main structural components: small, irregular, strained Co particles (60% of the entire Co population) and a composition modulated CoCu alloy. A high modulation amplitude of the concentration profile in the alloy subdivides the latter in two parts with distinctly different properties. One part consists of ferromagnetic alloy (average Cu concentration of about 20%) with a blocking temperature of about 35 K (involving 6% of the entire Co population in a sample). The other part, containing the remaining 34% of the entire Co population, is a paramagnetic alloy with a blocking temperature below 4.2 K. The ferromagnetic alloy is magnetically soft-its transverse susceptibility is lower by a factor of 7 than the transverse susceptibility of the quenched-in Co particles. The latter population has a blocking temperature of about 150-200 K. During the heat treatment, each of the two main structural components undergoes respective decomposition processes: both of them display two temperature regimes. One process consists in dissolving the quenched-in Co particles after annealing at around 400 degreesC, followed at higher temperatures by a nucleation and growth of the more regular in shape Co particles. The other process resembles a spinodal decomposition of the quenched-in CoCu alloy, resulting in sharpening of the concentration profile and eventually leading to Co cluster formation in samples annealed above 450 degreesC. Both processes end at about T-ap = 700 degreesC, in formation of large, pure Co clusters that are ferromagnetic at least up to 400 K.63

Electronic self-doping of Mo-states in A2FeMoO6 (A=Ca, Sr and Ba) half-metallic ferromagnets - a Nuclear Magnetic Resonance study

A systematic study of (A,A')2FeMoO6 (A,A'=Ca, Sr, Ba) ferromagnetic oxides with double perovskite structure has been performed using 95,97Mo and 57Fe NMR spectroscopy. These oxides are isoelectronic but have substantially different Curie temperatures. The NMR analysis provides clear evidence that the magnetic moment at Mo sites is not constant but varies sensitively with the ionic size of the alkaline ions. The 95,97Mo frequency, and thus the electronic charge at Mo ions, is found to be smaller in Ba and Ca than in Sr-based oxides. The charge release from Mo sites is accompanied by an uptake at Fe sites, and thus a self-doping Fe-Mo process is observed. This process is controlled by relevant structural parameters: the Fe-O-Mo bond length and bending. A clear relationship between the Curie temperature and the magnetic moment and thus electron density at Mo sites has been disclosed. The relevance of these findings for the understanding of ferromagnetic coupling in double perovskites is discussed.Comment: 26 pages, 8 figure

HLA class II DNA typing in a large series of European patients with systemic lupus erythematosus: correlations with clinical and autoantibody subsets

We conducted this study to determine the HLA class II allele associations in a large cohort of patients of homogeneous ethnic derivation with systemic lupus erythematosus (SLE). The large sample size allowed us to stratify patients according to their clinical and serologic characteristics. We studied 577 European Caucasian patients with SLE. Antinuclear antibodies (Hep-2 cells), anti-dsDNA antibodies (Crithidia luciliae), and antibodies to extractable nuclear antigens Ro (SS-A), La (SS-B), U1-RNP, Sm, Jo1, SCL70, and PCNA, were detected in all patients. Molecular typing of HLA-DRB1, DRB3, DQA1, and DQB1 loci was performed by the polymerase chain reaction-sequence specific oligonucleotide probes (PCR-SSOP) method. We found a significantly increased frequency of DRB1*03, DRB1*15, DRB1*16, DQA1*0102, DQB1*0502, DQB1*0602, DQB1*0201, DQB1*0303, and DQB1*0304 in lupus patients as compared with healthy controls. In addition, DRB1*03 was associated with anti-Ro, anti-La, pleuritis, and involvement of lung, kidney, and central nervous system. DRB1*15 and DQB1*0602 were associated with anti-dsDNA antibodies; DQB1*0201 with anti-Ro and anti-La, leukopenia, digital skin vasculitis, and pleuritis; and DQB1*0502 was associated with anti-Ro, renal involvement, discoid lupus, and livedo reticularis. In conclusion, our study shows some new HLA clinical and serologic associations in SLE and further confirms that the role of MHC genes is mainly to predispose to particular serologic and clinical manifestations of this disease

Treat-to-target in systemic lupus erythematosus: recommendations from an international task force.

The principle of treating-to-target has been successfully applied to many diseases outside rheumatology and more recently to rheumatoid arthritis. Identifying appropriate therapeutic targets and pursuing these systematically has led to improved care for patients with these diseases and useful guidance for healthcare providers and administrators. Thus, an initiative to evaluate possible therapeutic targets and develop treat-to-target guidance was believed to be highly appropriate in the management of systemic lupus erythematosus (SLE) patients as well. Specialists in rheumatology, nephrology, dermatology, internal medicine and clinical immunology, and a patient representative, contributed to this initiative. The majority convened on three occasions in 2012-2013. Twelve topics of critical importance were identified and a systematic literature review was performed. The results were condensed and reformulated as recommendations, discussed, modified and voted upon. The finalised bullet points were analysed for degree of agreement among the task force. The Oxford Centre level of evidence (LoE, corresponding to the research questions) and grade of recommendation (GoR) were determined for each recommendation. The 12 systematic literature searches and their summaries led to 11 recommendations. Prominent features of these recommendations are targeting remission, preventing damage and improving quality of life. LoE and GoR of the recommendations were variable but agreement was >0.9 in each case. An extensive research agenda was identified, and four overarching principles were also agreed upon. Treat-to-target-in-SLE (T2T/SLE) recommendations were developed by a large task force of multispecialty experts and a patient representative. It is anticipated that 'treating-to-target' can and will be applicable to the care of patients with SLE

Needs of work management connected with conservation of surface water and water facilities at restoration areas

W artykule przedstawiono: – Potrzeby prowadzenia prac związanych z utrzymaniem śródlądowych wód powierzchniowych i urządzeń wodnych zlokalizowanych na obszarach renaturyzowanych. – Zagrożenia jakie może spowodować brak tego rodzaju prac. – Rodzaje prac związanych z utrzymaniem i metody ich prowadzenia. – Wymagania szczególne, jakie stawiane są pracom utrzymaniowym na obszarach renaturyzowanych.This article present: – Needs of works management connected with conservation of surface water and water facilities at restoration areas. – Threats connected with lack of this kind of work. – Type of work connected with conservation and methods oh their management. – Requirements connected with conservation of work at restoration areas

Effects of SrTiO3 capping in La2/3Ca1/3MnO3 electrodes of different orientations

We report on the study of the structural, magnetic, and electronic properties of SrTiO3 capped La2/3Ca1/3MnO3 electrodes grown on (001) and (110) SrTiO3 substrates. Magnetic properties of the (001) and (110) capped electrodes evolve differently when the capping layer thickness increases, revealing a reduction of the saturation magnetization for the (001) ones. Electronic properties are studied combining 55Mn nuclear magnetic resonance (NMR) and x-ray photoemission spectroscopy (XPS). NMR experiments highlight that electronic phase separation in the (001) electrodes is enhanced by the presence of the SrTiO3 capping layer and XPS measurements show that the electronic state of interfacial Mn ions from (001) electrode is more sensitive to the capping layer

Insecticidal activity of some Bacillus strains against house fly larvae of Musca domestica

Insecticidal activity of B. thuringiensis subsp. morrisoni and B. thuringiensis subsp. darmstadiensis as well as B. sphaericus 2362 and 2297 was evaluated against larvae of the house fly (Musca domestica) under laboratory condition. The activity of all tested strains was similar, LC₅₀ ranges from 4 x 10⁷ to 1 x 10⁸ spores/ml. The higher spores conentration (2 x 10⁹) caused ca 70 per cent mortality. The relative low sensitivity of house fly larvae could results from weakly alcalic pH of the gut (7.6-7.8)