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We report on the effects of different multifilamentary geometries on the dynamic current and field distributions in YBa2Cu3O7-δ thin films. Finite-element model simulations are presented that allow a direct comparison of the calculated magnetic flux and current profiles with experimental data obtained by time-resolved magneto-optical imaging. We find that increasing the distance between filaments reduces the magnetic coupling and decreases the ac losses. Screening and transport currents also redistribute more evenly between all filaments. The measured transport current density profiles are in good agreement with the modified critical state model. [ABSTRACT FROM AUTHOR]

Multifilamentary coated conductor (MFCC) samples with patterned links have been studied using transport and scanning laser microscopy (SLM) techniques. Striation patterns are fashioned to define multiple filaments with discretely placed superconducting (SC) links between the filaments for current sharing and redistribution. After initial measurements, an artificial incision is made on a filament to mimic a disabled filament. The changes in global and local current transport characteristics are noted for in terms of the redistribution of current flow and the modification of local dissipation. Our results show that the patterned links between filaments play a vital role in redistributing current and encouraging current sharing. We find that the main factors in limiting the current-carrying capability of MFCC samples are local current density increases, which we call “current crowding.” The susceptible areas for current crowding are several: (1) filaments adjacent to the disabled ones, since the intact filaments have to carry extra current, (2) the links where current redistribution occurs, and (3) the partially blocked filament. [ABSTRACT FROM AUTHOR]

A simple investigation into the properties of weakly linked filaments in striated YBa2Cu3O7-d (YBCO) coated conductors has been performed. Such weak-link connections may arise in two different contexts within the coated conductors, the one case being the occurrence of unintentional connections. However, it may be desirable to intentionally induce the weak-link connections in order to allow a current sharing between the filaments. This allows the localized degradation of a given filament to be circumvented at a small cost in terms of the added losses and magnetization. This problem has been treated mathematically with a comparison of the superconductor weak linking in contrast to the normal-metal-induced current sharing. The estimates for target values of filament coupling are deduced, and the results in terms of magnetization are then determined. The YBCO samples created, using the pulsed laser deposition, are described that have these properties. The samples consist of one control and one striated sample. The magnetization response of these samples is then considered in terms of the expressions developed. [ABSTRACT FROM AUTHOR]

The thickness dependence of critical current density ([J.sub.c]) is examined in Y[Ba.sub.2][Cu.sub.3][O.sub.7-x] films with BaZr[O.sub.3] (BZO) nanorods (YBCO/BZO) aligned along the film normal. The results have shown that the thickness dependence of [J.sub.c] is dictated by the microstructure and hence pinning mechanism in YBCO films.

Byline: Paul Barnes It is only recently that market abuse, of which insider dealing is a form, has been unlawful in the UK. The general impression is that insider dealing is common, that the Financial Services Authority (FSA), the main regulator, is aware of this but is unable, except in the most obvious of cases, to prosecute at the criminal level. The picture is less clear for other forms of market abuse and the evidence as to their frequency of occurrence is conflicting. As a result we are unable to assess the extent to which these go unchecked.

Tomographic energy dispersive diffraction imaging (TEDDI) is used for characterizing the structure of a heterogeneous catalyst body in situ during thermal treatment, where Ni/[gamma]-[Al.sub.2][O.sub.3] hydrogenation catalyst bodies are chosen as the system of study. TEDDI has shown that the decomposition of [Ni(en)[([H.sub.2]O).sub.4]][Cl.sub.2] has taken place via two intermediate crystalline structures.

The effects of different multifilamentary geometries on the dynamic current and field distributions in Y[Ba.sub.2][Cu.sub.3][O.sub.7-[delta]] thin films are studied. The studies have shown that increasing the distance between filaments has reduced the magnetic coupling and has decreased the ac losses.

Byline: Paul Barnes, Michael B. Charles, Mark Branagan, Alistair Knight This article deals with the way in which intelligence flows and other critical information can be embedded into a risk framework that will facilitate the early warning of emerging threat scenarios. That is, an organisation should be able to anticipate crisis triggers and know when a crisis situation will manifest itself. As an outcome, a conceptual framework that defines how to make sense of complex situations, datasets and real world anomalies is suggested.

Transport and scanning laser microscopy (SLM) techniques are used for studying multifilamentary coated conductor (MFCC) samples with patterned links. The results have shown that the patterned links between filaments have played important role in redistributing current and encouraging current sharing.

Factors that influenced graduating high school seniors to pursue additional education after some gap after schooling are evaluated by focusing on Midwest region schools.

The properties of weakly linked filaments in striated YBa2CuO(sub 7-d) (YBCO) coated conductors are investigated. The results indicate the potential of using weakly linked striations to allow current sharing between high temperature superconductor (HTS) filaments of striated coated conductors while still reducing the associated hysteretic loss.

Plants perceive ultraviolet-B (UV-B) radiation through the UV-B photoreceptor UV RESISTANCE LOCUS 8 (UVR8), and initiate regulatory responses via associated signalling networks, gene expression and metabolic pathways. Various regulatory adaptations to UV-B radiation enable plants to harvest information about fluctuations in UV-B irradiance and spectral composition in natural environments, and to defend themselves against UV-B exposure. Given that UVR8 is present across plant organs and tissues, knowledge of the systemic signalling involved in its activation and function throughout the plant is important for understanding the context of specific responses. Fine-scale understanding of both UV-B irradiance and perception within tissues and cells requires improved application of knowledge about UV-attenuation in leaves and canopies, warranting greater consideration when designing experiments. In this context, reciprocal crosstalk among photoreceptor-induced pathways also needs to be considered, as this appears to produce particularly complex patterns of physiological and morphological response. Through crosstalk, plant responses to UV-B radiation go beyond simply UV-protection or amelioration of damage, but may give cross-protection over a suite of environmental stressors. Overall, there is emerging knowledge showing how information captured by UVR8 is used to regulate molecular and physiological processes, although understanding of upscaling to higher levels of organisation, i.e. organisms, canopies and communities remains poor. Achieving this will require further studies using model plant species beyond Arabidopsis, and that represent a broad range of functional types. More attention should also be given to plants in natural environments in all their complexity, as such studies are needed to acquire an improved understanding of the impact of climate change in the context of plant-UV responses. Furthermore, broadening the scope of experiments into the regulation of plant-UV responses will facilitate the application of UV radiation in commercial plant production. By considering the progress made in plant-UV research, this perspective highlights prescient topics in plant-UV photobiology where future research efforts can profitably be focussed. This perspective also emphasises burgeoning interdisciplinary links that will assist in understanding of UV-B effects across organisational scales and gaps in knowledge that need to be filled so as to achieve an integrated vision of plant responses to UV-radiation. [ABSTRACT FROM AUTHOR]

A Monte Carlo simulation of liquid water near a charged wall has been carried out for different values of the surface charge density. The surface excess of electric potential as a function of charge density has been determined from the polarization profiles. The differential capacity of the simulated system is compared with the differential capacity of the mercury/water interface. [ABSTRACT FROM AUTHOR]

The topotactic mechanism for the reduction of MoO3 to MoO2 is studied using well-supported experiments. The high quality in-situ Neutron Powder Diffraction (NPD) is used to monitor phase composition during the reduction of MoO3 in a flow of hydrogen at 550 degree Celsius.