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This is a copy of the slides presented at the meeting but not formally written up for the volume.
Complex oxides show a broad spectrum of intrinsic functionalities, such as ferroelectricity, magnetism, superconductivity or multiferroic behavior, which can be utilized and combined in electronic devices by the growth and design of heterostructures. Physical properties may arise in such multilayers that are not found in either of their constituents. A spectacular example for such a phenomenon, a conducting and highly mobile electron gas, is formed at the interface between the two insulating, dielectric perovskites LaAlO3 and SrTiO3  which can be easily tuned by transverse electric fields . In our contribution we will present recent studies of the microstructure of the multilayer and we will correlate them with the transport properties of the electron gas.  A. Ohtomo, H. Y. Hwang, Nature 427, 423-426 (2004).  S. Thiel, G. Hammerl, A. Schmehl, C. W. Schneider, J. Mannhart, Science 313, 1942-1945 (2006).
With the recent discovery of a dozen dusty star-forming galaxies and around 30 quasars at z > 5 that are hyper-luminous in the infrared (μ LIR > 1013 L⊙, where μ is a lensing magnification factor), the possibility has opened up for SPICA, the proposed ESA M5 mid-/far-infrared mission, to extend its spectroscopic studies toward the epoch of reionisation and beyond. In this paper, we examine the feasibility and scientific potential of such observations with SPICA’s far-infrared spectrometer SAFARI, which will probe a spectral range (35–230 μm) that will be unexplored by ALMA and JWST. Our simulations show that SAFARI is capable of delivering good-quality spectra for hyper-luminous infrared galaxies at z = 5 − 10, allowing us to sample spectral features in the rest-frame mid-infrared and to investigate a host of key scientific issues, such as the relative importance of star formation versus AGN, the hardness of the radiation field, the level of chemical enrichment, and the properties of the molecular gas. From a broader perspective, SAFARI offers the potential to open up a new frontier in the study of the early Universe, providing access to uniquely powerful spectral features for probing first-generation objects, such as the key cooling lines of low-metallicity or metal-free forming galaxies (fine-structure and H2 lines) and emission features of solid compounds freshly synthesised by Population III supernovae. Ultimately, SAFARI’s ability to explore the high-redshift Universe will be determined by the availability of sufficiently bright targets (whether intrinsically luminous or gravitationally lensed). With its launch expected around 2030, SPICA is ideally positioned to take full advantage of upcoming wide-field surveys such as LSST, SKA, Euclid, and WFIRST, which are likely to provide extraordinary targets for SAFARI.
A pilot study by 6 Clinical and Translational Science Awards (CTSAs) explored how bibliometrics can be used to assess research influence.
Evaluators from 6 institutions shared data on publications (4202 total) they supported, and conducted a combined analysis with state-of-the-art tools. This paper presents selected results based on the tools from 2 widely used vendors for bibliometrics: Thomson Reuters and Elsevier.
Both vendors located a high percentage of publications within their proprietary databases (>90%) and provided similar but not equivalent bibliometrics for estimating productivity (number of publications) and influence (citation rates, percentage of papers in the top 10% of citations, observed citations relative to expected citations). A recently available bibliometric from the National Institutes of Health Office of Portfolio Analysis, examined after the initial analysis, showed tremendous potential for use in the CTSA context.
Despite challenges in making cross-CTSA comparisons, bibliometrics can enhance our understanding of the value of CTSA-supported clinical and translational research.
Accurate models of X-ray absorption and re-emission in partly stripped ions are necessary to calculate the structure of stars, the performance of hohlraums for inertial confinement fusion and many other systems in high-energy-density plasma physics. Despite theoretical progress, a persistent discrepancy exists with recent experiments at the Sandia Z facility studying iron in conditions characteristic of the solar radiative–convective transition region. The increased iron opacity measured at Z could help resolve a longstanding issue with the standard solar model, but requires a radical departure for opacity theory. To replicate the Z measurements, an opacity experiment has been designed for the National Facility (NIF). The design uses established techniques scaled to NIF. A laser-heated hohlraum will produce X-ray-heated uniform iron plasmas in local thermodynamic equilibrium (LTE) at temperatures
eV and electron densities
. The iron will be probed using continuum X-rays emitted in a
diameter source from a 2 mm diameter polystyrene (CH) capsule implosion. In this design,
of the NIF beams deliver 500 kJ to the
mm diameter hohlraum, and the remaining
directly drive the CH capsule with 200 kJ. Calculations indicate this capsule backlighter should outshine the iron sample, delivering a point-projection transmission opacity measurement to a time-integrated X-ray spectrometer viewing down the hohlraum axis. Preliminary experiments to develop the backlighter and hohlraum are underway, informing simulated measurements to guide the final design.
This paper briefly describes the principle of operation and science goals of the AMANDA high energy neutrino telescope located at the South Pole, Antarctica. Results from an earlier phase of the telescope, called AMANDA-BIO, demonstrate both reliable operation and the broad astrophysical reach of this device, which includes searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, Gamma-Ray Bursts and diffuse sources. The predicted sensitivity and angular resolution of the telescope were confirmed by studies of atmospheric muon and neutrino backgrounds. We also report on the status of the analysis from AMANDA-II, a larger version with far greater capabilities. At this stage of analysis, details of the ice properties and other systematic uncertainties of the AMANDA-II telescope are under study, but we have made progress toward critical science objectives. In particular, we present the first preliminary flux limits from AMANDA-II on the search for continuous emission from astrophysical point sources, and report on the search for correlated neutrino emission from Gamma Ray Bursts detected by BATSE before decommissioning in May 2000. During the next two years, we expect to exploit the full potential of AMANDA-II with the installation of a new data acquisition system that records full waveforms from the in-ice optical sensors.
Eddington is a space mission for extrasolar planet finding and for asteroseismic observations. It has been selected by ESA as an F2/F3 reserve mission with a potential implementation in 2008-13. Here we describe Eddington's capabilities to detect extrasolar planets, with an emphasis on the detection of habitable planets. Simulations covering the instrumental capabilities of Eddington and the stellar distributions in potential target fields lead to predictions of about 10,000 planets of all sizes and temperatures, and a few tens of terrestrial planets that are potentially habitable. Implications of Eddington for future larger scale missions are briefly discussed.
The ESRO satellite COS-B carries one single experiment aiming at the measurement of arrival direction and energy of celestial gamma rays with energies between 25 MeV and 10 GeV. The experiment is conventional in design and consists of a veto counter, a wire spark chamber, a telescope and an energy calorimeter.
The energy measurement is obtained by a CsI scintillation crystal of 4.7 radiation length thickness. The expected energy resolution at 100 MeV is 50% FWHM. The other detector elements are designed as to cause the least possible degradation of the energy measurement.
The possibilities for the detection of a small contribution of π -origin gamma rays in the presence of a power-law type background spectrum will be discussed.
The B fields in OB stars (BOB) survey is an ESO large programme collecting spectropolarimetric observations for a large number of early-type stars in order to study the occurrence rate, properties, and ultimately the origin of magnetic fields in massive stars. As of July 2014, a total of 98 objects were observed over 20 nights with FORS2 and HARPSpol. Our preliminary results indicate that the fraction of magnetic OB stars with an organised, detectable field is low. This conclusion, now independently reached by two different surveys, has profound implications for any theoretical model attempting to explain the field formation in these objects. We discuss in this contribution some important issues addressed by our observations (e.g., the lower bound of the field strength) and the discovery of some remarkable objects.
Zn(S,O,OH) Chemical Bath Deposited (CBD) remains one of the most studied Cd-free buffer layer for replacing the CBD-CdS buffer layer in a Cu(In,Ga)Se2-based (CIGSe) solar cells and has already demonstrated its potential to lead to high-efficiencies. However, in order to further increase the deposition rate of the Zn(S,O,OH) layer during the CBD, the inclusion of additives can be a reasonable strategy, as long as the efficiencies of solar cells are maintained. The aim of this work is to understand the effect of the introduction of additives such as hydrogen peroxide (H2O2), H2O2+ethanolamine (C2H7NO) and H2O2+tri-sodium citrate (Na3C6H5O7) during CBD on the deposition mechanism, the growth rate and the quality of the buffer layer. It has been shown that the combined use of H2O2 and citrate in the bath formulation allows the deposition of Zn(S,O,OH) via a mix of “ion-by-ion” and “cluster-by-cluster” mechanisms that have good properties as buffer layers leading to high efficiency solar cells.
With the ICRP recommendations Publications 103, 109 and 111 (ICRP, 2007; ICRP 2009a,
2009b), new concepts and quantities have been introduced into emergency management and
rehabilitation. Two of them will possibly influence national procedures, but for sure they
will influence countermeasure simulation approaches: 1. The concept of a “reference level”
for emergency and existing controllable exposure situations that represents the level of
dose or risk, above which it is judged to be inappropriate to plan to allow exposures to
occur, and for which therefore protective actions should be planned in advance. 2. When
deciding on the optimum course of protective actions, all exposure pathways and all
relevant actions have to be taken into account. The major changes for the simulation
models result from the second recommendation that all exposure pathways must be considered
when deciding on protective actions. So far all countermeasure simulations in the early
phase of an emergency are carried out by considering individual countermeasures such as
sheltering or evacuation, if some dose limit for the respective action is exceeded. This
approach has to be changed and strategies of several countermeasures analysed and
simulated with the ultimate goal not to exceed the reference level over a given time
period, typically one year.
In April 2011 the European Platform on Preparedness for Nuclear and Radiological
Emergency Response and Recovery (NERIS-TP) decided to expand the two European Decision
Support Systems JRodos and ARGOS with respect to the new ICRP-103 recommendations. The
extension should be applicable for nuclear accidents and radiological emergencies and
comprise a new screening model, the possibility to optimise dose reducing actions with the
models ERMIN (European Model for Inhabited Areas) and AGRICP (Agricultural Countermeasure
Program), respectively, and scenario preparation tools to support the user in defining
countermeasure strategies. This paper describes the screening model that was developed by
the authors and is foreseen for realisation and inclusion in JRodos and ARGOS in
The nuclear reactor remote monitoring system of the federal state of Baden- Wuerttemberg
(KFUe BW) is realized according to the renewed “recommendations for remote monitoring of
nuclear power plants” (BMU, 2005a). The spectrum of the system covers both, pursuit of
operational procedures, and incidents or accidents. The KFUe BW provides a measurement
network and information system for operational parameters at the plant sites as well as
radiological and meteorological measurements in their vicinity. For the Ministry, it
preferentially serves as an instrument of nuclear supervision. This paper gives a brief
survey of the system architecture and concentrates on the role of the KFUe with respect to
the determination and evaluation of the radiological situation in the range of off-site
Rangea is the type genus of the Rangeomorpha, an extinct clade near the base of the evolutionary tree of large, complex organisms which prospered during the late Neoproterozoic. It represents an iconic Ediacaran taxon, but the relatively few specimens previously known significantly hindered an accurate reconstruction. Discovery of more than 100 specimens of Rangea in two gutter casts recovered from Farm Aar in southern Namibia significantly expands this data set, and the well preserved internal and external features on these specimens permit new interpretations of Rangea morphology and lifestyle. Internal structures of Rangea consist of a hexaradial axial bulb that passes into an axial stalk extending the length of the fossil. The axial bulb is typically filled with sediment, which becomes increasingly loosely packed and porous distally, with the end of the stalk typically preserved as an empty, cylindrical cone. This length of the axial structure forms the structural foundation for six vanes arranged radially around the axis, with each vane consisting of a bilaminar sheet composed of a repetitive pattern of elements exhibiting at least three orders of self-similar branching. Rangea was probably an epibenthic frond that rested upright on the sea bottom, and all known fossil specimens were transported prior to their final burial in storm deposits.
To assess healthcare personnel (HCP) perceptions regarding implementation of sensor-based electronic systems for automated hand hygiene adherence monitoring.
Using a mixed-methods approach, structured focus groups were designed to elicit quantitative and qualitative responses on familiarity, comfort level, and perceived impact of sensor-based hand hygiene adherence monitoring
A university hospital, a Veterans Affairs hospital, and a community hospital in the Midwest.
Focus groups were homogenous by HCP type, with separate groups held for leadership, midlevel management, and frontline personnel at each hospital.
Overall, 89 HCP participated in 10 focus groups. Levels of familiarity and comfort with electronic oversight technology varied by HCP type; when compared with frontline HCP, those in leadership positions were significantly more familiar with (P<.01) and more comfortable with (P<.01) the technology. The most common concerns cited by participants across groups included lack of accuracy in the data produced, such as the inability of the technology to assess the situational context of hand hygiene opportunities, and the potential punitive use of data produced. Across groups, HCP had decreased tolerance for electronic collection of spatial-temporal data, describing such oversight as Big Brother.
While substantial concerns were expressed by all types of HCP, participants' recommendations for effective implementation of electronic oversight technologies for hand hygiene monitoring included addressing accuracy issues before implementation and transparent communication with frontline HCP about the intended use of the data.
Ionization energies and electron affinities of clean AlxGa1−xN(0001) surfaces were investigated by ultraviolet photoemission spectroscopy over the whole composition range. The samples were cleaned with cycles of N+-ion sputtering and annealing partly within a Ga atom flux. The ionization energy is measured as 6.5 eV and is almost independent of the aluminum content in good agreement with the general chemical trend. The electron affinity decreases linearly with composition from 3.1 eV for GaN to 0.25 eV for AlN. No evidence for negative electron affinity at AlN(0001) surfaces was found. Adsorption of oxygen at room temperature leads to a significant increase of the ionization energy and electron affinity. With AlN(0001) surfaces, an oxygen uptake of 0.6 monolayers is observed after exposures of 108 Langmuirs and the ionization energy increases by approximately 2 eV.
Single crystals of R1Ba2Cu3O7–8, (R=Y, Eu and Gd), have been irradiated with 0.4–1.0 MeV electrons in directions near the c-axis. An incident threshold electron energy for producing flux pinning defects has been found. In-situ TME studies found no visible defects induced by electron irradiation. This means that point defects or small clusters ( ≤ 20 Å) are responsible for the extra pinning. A consistent interpretation of the data suggests that the most likely pinning defect is the displacement of a Cu atom from the CuO2 planes.
A second-order vortex-solid melting transition in twinned Y-Ba-Cu-O single crystals is manifested by two independent types of electrical transport measurements: the electric field (E) versus current density (J) isotherms, and the ac resistivity (ρ) vs current frequency (ω) isotherms. Universal static and dynamic exponents (ν ≈ 2/3 and Ζ ≈ 3, respectively) are found for magnetic fields ranging from 1 to 90 kOe, frequencies ranging from 0 to 2 MHz, magnetic directions parallel and perpendicular to the crystal c-axis, as well as samples with and without proton irradiations. At microwave frequencies, we find that the vortex dissipation in Nd-Ce-Cu-O epitaxial films is consistent with the viscous motion of individual vortices, due to the break down of the critical scaling theory in the high frequency limit.
To assess a Ni-clad melt-processed YBa2Cu3Oy (YBCO) conductor approach, a systematic study was made on commercially available YBCO powder mixed and co-sintered with nickel oxide (NiO). Our research effort has focused on the effect of nickel on the critical current density in the YBCO/Ni composites. Four series of YBCO samples mixed with 0.3, 0.7, 1, 1.3, 2 and 3 wt% of high purity NiO were prepared, and optimized conditions for the melt process were established. These samples were characterized by resistivity, AC susceptibility and DC magnetization measurements. The highest magnetization critical current density (Jcm∼3×105 A/cm2 at T=4.2K and H=0 was observed in melt-processed samples with ∼ 1 wt% Ni (or -1.3 wt% NiO) subjected to a cooling rate of 2°C/hr from 1040°C to 980°C. This Jcm was found near the middle of the Ni-solubility range (about 2 wt% Ni is the solubility limit of Ni in YBCO) which may be attributed to the local Ni/Cu compositional fluctuation leading to an increased pinning force density in these composites.
-Heteroepitaxial superconducting Bi,Sr2CaCu2Ox (BSCCO 2212) thin films have been formed by solid phase epitaxy from amorphous films deposited on (100) LaA1O3 single crystal substrates by organometallic chemical vapor deposition. The epitaxial structure of the film is confirmed by x-ray diffraction including θ/2θ and Φ (in plane rotation) scans. Cross-sectional high resolution transmission electron microscopy indicates that the film-substrate interface is nearly atomically abrupt. Improvements in superconducting properties of the epitaxial thin films are noted in comparison to highly textured films deposited on MgO.