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Develops a high-temperature X-ray-diffractometer stage specifically designed for low-angle measurements of multilayers. Combination of low-angle X-ray diffraction measurements of multilayers with in situ annealing; Thermal-expansion coefficient of a metallic multilayered system; Changes in the structure W/Cu multilayers.

We derive a spin-diffusion length at 4.2 K in sputtered Au, l[SUBsf,SUPAu] = 35[SUB-5,SUP+65] nm, spin-memory-loss at Au/Cu interfaces, δ[SUBAu/Cu] = 0.13[SUB-0.02,SUP+0.08], and Au/Cu interface specific resistance, 2AR[SUBAu/Cu] = 0.35[SUB-0.05,SUP+0.10] fΩ m[SUP2]. We also show that exchange biased spin valves with Au sandwiched between Co layers produce changes in specific resistance, A Δ R, comparable to those for Cu and Ag. [ABSTRACT FROM AUTHOR]

Objective and background: Childhood community-acquired pneumonia (CAP) remains a leading cause of morbidity and mortality worldwide. The features of childhood CAP vary between countries. The aim of this study was to delineate the clinical characteristics, complications, spectrum of pathogens and patterns of antimicrobial resistance associated with hospitalized cases of childhood CAP in Singapore. Methods: A retrospective study was conducted of patients discharged from Singapore’s only children’s hospital over a 3-year period with a principal diagnosis of CAP. Results: A total of 1702 children, with a median age of 4.2 years (range: 1 month−16.3 years) were enrolled. A pathogen was identifiable in 38 .4% of cases, including Mycoplasma pneumoniae in 20.3%, typical respiratory bacteria in 10.3% (64.6% Streptococcus pneumoniae; 21.7% non-typeable Haemophilus influenzae), viruses in 5.5% and mixed bacterial/viral infections in 2%. The majority of M. pneumoniae infections were in school-aged children (>5 years). Severity of infection was greater in CAP caused by typical bacteria, as reflected by length of hospital stay, CRP level, white cell and absolute neutrophil counts. Mortality from typical bacterial infections (8.9%) exceeded that from M. pneumoniae (0.3%) and viral pneumonias (0%) ( P < 0.001). Aminopenicillins were often prescribed empirically for suspected S. pneumoniae and H. influenzae infections; however, resistance to these agents was frequently documented among S. pneumoniae (58.5%) and H. influenzae isolates (51%). Conclusion: In Singaporean children hospitalized with CAP, M. pneumoniae is the most commonly identified causative organism, followed by common respiratory viruses, S. pneumoniae and H. influenzae. Streptococcus pneumoniae and H. influenzae are associated with greater severity of infection than other organisms, and have high levels of resistance to commonly prescribed antibiotics. [ABSTRACT FROM AUTHOR]

Reports on the synthesis, characterization, thermal decomposition and full hydrolysis of heterometallic copper oxide-alkoxides. Effects of ligand composition and metal oxidation state on the properties of copper-containing precursors; Effect of oxo ligands on the stability and decomposition mechanisms and products of mono and divalent copper-zirconium isopropoxides.

Giant magnetoresistance (GMR) type Co-Cu multilayers and exchange-biased spin-valve (EBSV) type Co-Cu-Co tri-layers are fabricated by sputtering with a thin layer of Ag inserted between Co and Cu as a surface modifier (SM). Their magnetoresistances (MR) are measured in both current-perpendicular-to-plane (CPP) and current-in-plane (CIP) configurations. In all situations, the size of the MR change decreases as the Ag SM is introduced, and the effect is interface related. [ABSTRACT FROM AUTHOR]

The dependence of magnetotransport on field orientation is an important issue in spintronics-related devices where the applied field is not necessarily in the ideal field-in-plane (FIP) geometry. In this study, we perform tunneling magnetoresistance (TMR) measurements on Co-Al2 O3-CoFe-NiFe spin-dependent tunnel (SDT) junctions prepared at different conditions with varying field orientation ranging from FIP to field-perpendicular-to-plane (FPP). The TMR ratio decreases drastically, whereas the switching field of Co increases when the field direction is set close to FPP. Furthermore, in a situation near FPP, a peculiar TMR looping behavior is observed for one set of samples. Interface effect is thought to be related. [ABSTRACT FROM AUTHOR]

We have employed ferromagnetic resonance to obtain magnetic anisotropy information in a series of YIG/GGG superlattices and a single YIG thin film with temperature variations. The Curie temperature of these samples increases with the YIG layer thickness, reaching saturation beyond a specific YIG thickness. As temperature rises, the magnitude of the calculated magnetocrystalline anisotropy constant decreases while the uniaxial anisotropy constant exhibits growing behavior. [Copyright &y& Elsevier]

Abstract: We investigate Co/Nb multilayers to explore the spontaneous π-phase shift between the superconducting (SC) layers, which is attributed for causing the non-monotonic change of the SC transition temperature (T c) with the ferromagnetic (FM) layer thickness (t FM) in several FM/SC multilayered systems. The issue of interfacial roughness is also explored by growing Co/Nb multilayers at various sputtering pressures. Transport measurements show a non-monotonic dependence of T c on t FM, and this dependence is insensitive to the structural variation present in the samples, as measured by X-ray scattering. [Copyright &y& Elsevier]

The phase diagram obtained for Nd0.5Ca0.5-ySryMnO3 from the temperature dependent magnetization and electron spin resonance measurements are presented in this paper. It is found from magnetization measurements that y=0.25 is a critical point where a magnetic transformation occurs, accompanied by a nonmonotonic variation in the c lattice parameter. Below a certain transition temperature, compounds with y<0.25 exhibit charge ordering and those with y≥0.25 show ferromagnetic ordering. An antiferromagnetic transition occurs for y=0 at still lower temperatures whereas a phase separation into antiferromagnetically and ferromagnetically ordered states occurs for 00. [ABSTRACT FROM AUTHOR]