Nonlinear phenomena in multiferroic nanocapacitors:joule heating and electromechanical effects

We demonstrate an approach for probing nonlinear electromechanical responses in BiFeO(3) thin film nanocapacitors using half-harmonic band excitation piezoresponse force microscopy (PFM). Nonlinear PFM images of nanocapacitor arrays show clearly visible clusters of capacitors associated with variations of local leakage current through the BiFeO(3) film. Strain spectroscopy measurements and finite element modeling point to significance of the Joule heating and show that the thermal effects caused by the Joule heating can provide nontrivial contributions to the nonlinear electromechanical responses in ferroic nanostructures. This approach can be further extended to unambiguous mapping of electrostatic signal contributions to PFM and related techniques.

High concentrations of AGE-LDL and oxidized LDL in circulating immune complexes are associated with progression of retinopathy in type 1 diabetes

To determine whether immunocomplexes (ICs) containing advanced glycation end product (AGE)-LDL (AGE-LDL) and oxidized LDL (oxLDL) contribute to the development of retinopathy over a 16-year period in subjects with type 1 diabetes.

Measuring math anxiety in Italian college and high school students: Validity, reliability and gender invariance of the Abbreviated Math Anxiety Scale (AMAS)

Given that the ability to manage numbers is essential in a modern society, mathematics anxiety – which has been demonstrated to have unfortunate consequences in terms of mastery of math – has become a subject of increasing interest, and the need to accurately measure it has arisen. One of the widely employed scales to measure math anxiety is the Abbreviated Math Anxiety Scale (AMAS) (Hopko, Mahadevan, Bare & Hunt, 2003). The first aim of the present paper was to confirm the factor structure of the AMAS when administered to Italian high school and college students, and to test the invariance of the scale across educational levels. Additionally, we assessed the reliability and validity of the Italian version of the scale. Finally, we tested the invariance of the AMAS across genders. The overall findings provide evidence for the validity and reliability of the AMAS when administered to Italian students.

The influence of high-temperature sintering on microstructure and mechanical properties of free-standing APS CeO-YO -ZrO coatings

In this study, ceria-yttria co-stabilized zirconia (CYSZ) free-standing coatings, deposited by air plasma spraying (APS), were isothermally annealed at 1315 °C in order to explore the effect of sintering on the microstructure and the mechanical properties (i.e., hardness and Young's modulus). To this aim, coating microstructure, before and after heat treatment, was analyzed using scanning electron microscopy, and image analysis was carried out in order to estimate porosity fraction. Moreover, Vickers microindentation and depth-sensing nanoindentation tests were performed in order to study the evolution of hardness and Young's modulus as a function of annealing time. The results showed that thermal aging of CYSZ coatings leads to noticeable microstructural modifications. Indeed, the healing of finer pores, interlamellar, and intralamellar microcracks was observed. In particular, the porosity fraction decreased from ~10 to ~5% after 50 h at 1315 °C. However, the X-ray diffraction analyses revealed that high phase stability was achieved, as no phase decomposition occurred after thermal aging. In turn, both the hardness and Young's modulus increased, in particular, the increase in stiffness (with respect to "as produced" samples) was equal to ~25%, whereas the hardness increased to up to ~60%. © 2010 Springer Science+Business Media, LLC.

Influence of strain and polycrystalline ordering on magnetic properties of high moment rare earth metals and alloys

Despite being the most suitable candidates for solenoid pole pieces in state-of-the-art superconductor- based electromagnets, the intrinsic magnetic properties of heavy rare earth metals and their alloys have gained comparatively little attention. With the potential of integration in micro- and nanoscale devices, thin films of Gd, Dy, Tb, DyGd and DyTb were plasma-sputtered and investigated for their in-plane magnetic properties, with an emphasis on magnetisation vs. temperature profiles. Based on crystal structure analysis of the polycrystalline rare earth films, which consist of a low magnetic moment FCC layer at the seed interface topped with a higher moment HCP layer, an experimental protocol is introduced which allows the direct magnetic analysis of the individual layers. In line with the general trend of heavy lanthanides, the saturation magnetisation was found to drop with increasing unit cell size. In-situ annealed rare earth films exceeded the saturation magnetisation of a high-moment Fe65Co35 reference film in the cryogenic temperature regime, proving their potential for pole piece applications; however as-deposited rare earth films were found completely unsuitable. In agreement with theoretical predictions, sufficiently strained crystal phases of Tb and Dy did not exhibit an incommensurate magnetic order, unlike their single-crystal counterparts which have a helical phase. DyGd and DyTb alloys followed the trends of the elemental rare earth metals in terms of crystal structure and magnetic properties. Inter-rare-earth alloys hence present a desirable blend of saturation magnetisation and operating temperature.

Child Maltreatment and High Risk Families: Protecting children and young people

Most child maltreatment occurs within the context of high risk families. There are ethical, economic and ecological reasons why physical abuse in such families should be a major concern. Physical abuse is a significant issue throughout the UK. Yet, while neglect and other forms of abuse are receiving focused attention, physical abuse may languish under the misconceptions that it is no longer a problem, is addressed elsewhere, or is just too overwhelming an issue.
The physical abuse of children can involve regular, violent treatment at the hands of parents or carers over a number of years. Its physical effects may last for days and may result in actual physical injury. It is not accidental. Although physical abuse can occur in any family, it is prevalent in particular sectors of society, where families may be vulnerable to a combination of complex risk factors such as domestic abuse, alcohol and drug (mis)use, and mental health issues. These factors are present in 34% of Serious Case Reviews (SCRs).
The authors provide an increased understanding of risk, analysis, impact, learning and the current landscape of service delivery in relation to the physical abuse of children living in high risk families for professional, postgraduate and policy-making audiences.

Summary of the Snowmastodon Project Special Volume: A high-elevation, multi-proxy biotic and environmental record of MIS 6-4 from the Ziegler Reservoir fossil site, Snowmass Village, Colorado, USA

In North America, terrestrial records of biodiversity and climate change that span Marine Oxygen Isotope Stage (MIS) 5 are rare. Where found, they provide insight into how the coupling of the ocean-atmosphere system is manifested in biotic and environmental records and how the biosphere responds to climate change. In 2010-2011, construction at Ziegler Reservoir near Snowmass Village, Colorado (USA) revealed a nearly continuous, lacustrine/wetland sedimentary sequence that preserved evidence of past plant communities between similar to 140 and 55 lea, including all of MIS 5. At an elevation of 2705 m, the Ziegler Reservoir fossil site also contained thousands of well-preserved bones of late Pleistocene megafauna, including mastodons, mammoths, ground sloths, horses, camels, deer, bison, black bear, coyotes, and bighorn sheep. In addition, the site contained more than 26,000 bones from at least 30 species of small animals including salamanders, otters, muskrats, minks, rabbits, beavers, frogs, lizards, snakes, fish, and birds. The combination of macro- and micro-vertebrates, invertebrates, terrestrial and aquatic plant macrofossils, a detailed pollen record, and a robust, directly dated stratigraphic framework shows that high-elevation ecosystems in the Rocky Mountains of Colorado are climatically sensitive and varied dramatically throughout MIS 5 

Origin of extraordinarily high catalytic activity of Co3O4 and its morphological chemistry for CO oxidation at low temperature

Understanding and then designing efficient catalysts for CO oxidation at low temperature is one of the hottest topics in heterogeneous catalysis. Among the existing catalysts. Co3O4 is one of the most interesting systems: Morphology-controlled Co3O4 exhibits exceedingly high activity. In this study, by virtue of extensive density functional theory (OFT) calculations, the favored reaction mechanism in the system is identified. Through careful analyses on the energetics of elementary reactions on Co3O4(1 1 0)-A, Co3O4(1 1 0)-B, Co3O4(1 1 1) and Co3O4(1 0 0), which are the commonly exposed surfaces of Co3O4, we find the following regarding the relation between the activity and structure: (i) Co3+ is the active site rather than Co2+: and (ii) the three-coordinated surface oxygen bonded with three Co3+ may be slightly more reactive than the other two kinds of lattice oxygen, that is, the two-coordinated 0 bonded with one Co2+ and one Co3+ and the three-coordinated 0 bonded with one Co2+ and two Co3+. Following the results from Co3O4, we also extend the investigation to MnO2(1 1 0), Fe3O4(1 1 0), CuO(1 1 0) and CuO(1 1 1), which are the common metal oxide surfaces, aiming to understand the oxides in general. Three properties, such as the CO adsorption strength, the barrier of CO reacting with lattice 0 and the redox capacity, are identified to be the determining factors that can significantly affect the activity of oxides. Among these oxides, Co3O4 is found to be the most active one, stratifying all the three requirements. A new scheme to decompose barriers is introduced to understand the activity difference between lattice O-3c and O-2c on (1 1 0)-B surface. By utilizing the scheme, we demonstrate that the origin of activity variance lies in the geometric structures. (C) 2012 Elsevier Inc. All rights reserved.