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This is a copy of the slides presented at the meeting but not formally written up for the volume.
Ferromagnetism and superconductivity are long range ordering principles with a mutual exclusion in homogeneous systems. However, if they are spatially separated as in thin film heterostructutres and superlattices both properties are appearing simultaneously and their interaction can be studies. Heterostructures and superlattices consisting of the half-metal ferromagnet La0.67.Ca.33MnO3 and superconducting YBa2Cu3O7 layers were fabricated by pulsed laser deposition techniques and their magnetic as well as electronic interaction studies by a variety of techniques ranging from transport measurements to magnetic, neutron diffraction and XMCD analysis. It turns out that at the interface interaction effe3cts are taking place at two different length scales. One is based on the self - injection of spin-polarized quasiparticles with a length scale of ~ 10nm, the other is a short range exchange interaction with a length scale of ~ 3 nm. Furthermore, it could be shown that an so far unknown coupling of adjacent magnetic layers occurs when the superlattices are cooled through the superconducting transition temperature. The paper describes the RHEED- controlled growth of the superlattices as well as the relevant physics occuring at the interface.
The aim of this study was to assess the impact of a urinary tract infection (UTI) management bundle to reduce the treatment of asymptomatic bacteriuria (AB) and to improve the management of symptomatic UTIs.
Before-and-after intervention study.
Consecutive sample of inpatients with positive single or mixed-predominant urine cultures collected and reported while admitted to the hospital.
The UTI management bundle consisted of nursing and prescriber education, modification of the reporting of positive urine cultures, and pharmacists’ prospective audit and feedback. A retrospective chart review of consecutive inpatients with positive urinary cultures was performed before and after implementation of the management bundle.
Prior to the implementation of the management bundle, 276 patients were eligible criteria for chart review. Of these 276 patients, 165 (59·8%) were found to have AB; of these 165 patients with AB, 111 (67·3%) were treated with antimicrobials. Moreover, 268 patients met eligibility criteria for postintervention review. Of these 268, 133 patients (49·6%) were found to have AB; of these 133 with AB, 22 (16·5%) were treated with antimicrobials. Thus, a 75·5% reduction of AB treatment was achieved. Educational components of the bundle resulted in a substantial decrease in nonphysician-directed urine sample submission. Adherence to a UTI management algorithm improved substantially in the intervention period, with a notable decrease in fluoroquinolone prescription for empiric UTI treatment.
A UTI management bundle resulted in a dramatic improvement in the management of urinary tract infection, particularly a reduction in the treatment of AB and improved management of symptomatic UTI.
Many fluctuation-driven phenomena in fluids can be analysed effectively using the generalised Lagrangian-mean (GLM) theory of Andrews & McIntyre (J. Fluid Mech., vol. 89, 1978, pp. 609–646) This finite-amplitude theory relies on particle-following averaging to incorporate the constraints imposed by the material conservation of certain quantities in inviscid regimes. Its original formulation, in terms of Cartesian coordinates, relies implicitly on an assumed Euclidean structure; as a result, it does not have a geometrically intrinsic, coordinate-free interpretation on curved manifolds, and suffers from undesirable features. Motivated by this, we develop a geometric generalisation of GLM that we formulate intrinsically using coordinate-free notation. One benefit is that the theory applies to arbitrary Riemannian manifolds; another is that it establishes a clear distinction between results that stem directly from geometric consistency and those that depend on particular choices. Starting from a decomposition of an ensemble of flow maps into mean and perturbation, we define the Lagrangian-mean momentum as the average of the pull-back of the momentum one-form by the perturbation flow maps. We show that it obeys a simple equation which guarantees the conservation of Kelvin’s circulation, irrespective of the specific definition of the mean flow map. The Lagrangian-mean momentum is the integrand in Kelvin’s circulation and distinct from the mean velocity (the time derivative of the mean flow map) which advects the contour of integration. A pseudomomentum consistent with that in GLM can then be defined by subtracting the Lagrangian-mean momentum from the one-form obtained from the mean velocity using the manifold’s metric. The definition of the mean flow map is based on choices made for reasons of convenience or aesthetics. We discuss four possible definitions: a direct extension of standard GLM, a definition based on optimal transportation, a definition based on a geodesic distance in the group of volume-preserving diffeomorphisms, and the ‘glm’ definition proposed by Soward & Roberts (J. Fluid Mech., vol. 661, 2010, pp. 45–72). Assuming small-amplitude perturbations, we carry out order-by-order calculations to obtain explicit expressions for the mean velocity and Lagrangian-mean momentum at leading order. We also show how the wave-action conservation of GLM extends to the geometric setting. To make the paper self-contained, we introduce in some detail the tools of differential geometry and main ideas of geometric fluid dynamics on which we rely. These include variational formulations which we use for alternative derivations of some key results. We mostly focus on the Euler equations for incompressible inviscid fluids but sketch out extensions to the rotating–stratified Boussinesq, compressible Euler, and magnetohydrodynamic equations. We illustrate our results with an application to the interaction of inertia-gravity waves with balanced mean flows in rotating–stratified fluids.
Actinobacillus pleuropneumoniae is a Gram-negative bacterium that belongs to the family Pasteurellaceae. It is the causative agent of porcine pleuropneumonia, a highly contagious respiratory disease that is responsible for major economic losses in the global pork industry. The disease may present itself as a chronic or an acute infection characterized by severe pathology, including hemorrhage, fibrinous and necrotic lung lesions, and, in the worst cases, rapid death. A. pleuropneumoniae is transmitted via aerosol route, direct contact with infected pigs, and by the farm environment. Many virulence factors associated with this bacterium are well characterized. However, much less is known about the role of biofilm, a sessile mode of growth that may have a critical impact on A. pleuropneumoniae pathogenicity. Here we review the current knowledge on A. pleuropneumoniae biofilm, factors associated with biofilm formation and dispersion, and the impact of biofilm on the pathogenesis A. pleuropneumoniae. We also provide an overview of current vaccination strategies against A. pleuropneumoniae and consider the possible role of biofilms vaccines for controlling the disease.
We present NH3(J,K) = (1,1) observations toward CS(2,1) sources in the southern hemisphere, obtained with the Itapetinga Radio Telescope, that exhibit departure from LTE conditions. The mechanism of selective trapping in the hyperfine transitions of NH3(J, K) =(2,1)-(1,1) is invoked to explain the non-thermal population in the NH3(J, K) = (1,1) hyperfine states. This effect is relevant only when the width of the hyperfine lines lie between 0.3 and 0.6 km s−1. Due to this restriction, the assumption that the molecular cloud is formed by clumps, which produce spectra within this line-width interval seems to be a natural explanation for the non-thermal population. The observed spectra can be the result of the superposition of individual clump spectra with different central velocities. This model was applied to determine the physical conditions of the observed regions, providing satisfactory results for most of them. However, for some sources the model is not adequate to reproduce the observations, indicating that some other effects should be included, such as IR continuum, that was neglected in the radiative transfer calculations.
This paper presents radiocarbon results from a single Diploastrea heliopora coral from Vanuatu that lived during the Younger Dryas climatic episode, between ca. 11,700 and 12,400 calendar yr bp. The specimen has been independently dated with multiple 230Th measurements to permit calibration of the 14C time scale. Growth bands in the coral were used to identify individual years of growth. 14C measurements were made on each year. These values were averaged to achieve decadal resolution for the 14C calibration. The relative uncertainty of the decadal 14C data was below 1% (2σ). The data are in good agreement with the existing dendrochronology and allow for high-resolution calibration for most years. Variations in the fine structure of the 14C time series preserved in this specimen demonstrate sporadic rapid increases in the Δ14C content of the surface ocean and atmosphere. Certain sharp rises in Δ14C are coincident with gaps in coral growth evidenced by several hiatuses. These may be related to rapid climatic changes that occurred during the Younger Dryas. This is the first coral calibration with decadal resolution and the only such data set to extend beyond the dendrochronology-based 14C calibration.
We review our knowledge of the composition of cometary volatiles in the light of recent observations of comets C/1996 B2 (Hyakutake) and C/1995 01 (Hale-Bopp) and examine how this could constrain models of planetary system formation.
We present near-infrared spectroscopy of low-mass companions in the HD 130948 system (Goto et al. 2002a). Adaptive optics on the Subaru Telescope allowed for spectroscopy of the individual components of the 0″.13 binary system. Based on a direct comparison with a series of template spectra, we determined the spectral types of HD 130948B and C to be L4 ± 1. We find they are most likely a binary brown dwarf system.
We report the direct detection of cyclic diameter variations in the Mira variable χ Cygni. Interferometric observations made between 1997 July and 1998 September, using the Cambridge Optical Aperture Synthesis Telescope (COAST) indicate periodic changes in the apparent angular diameter with amplitude 45 per-cent of the smallest value.
The measurements were made in a 50 nm bandpass centred on 905 nm, which is only moderately contaminated by molecular absorption features. To assess the effects of atmospheric stratification on the apparent diameter measured in this band, we have also measured near-infrared diameters for a sample of five Miras, in both the J-band (1.3 μm) and Wing's (1971) 1.04 μm band, which is expected to isolate essentially pure continuum emission. We present J-band visibility curves which indicate that the intensity profiles of the stars in the sample differ greatly from each other.
The Late weichselian Pleniglacial wind regime in the eastern Netherlands is reconstructed by means of landform and sedimentological analysis. This analysis involves aeolian and fluvial landforms in the Dinkel river valley in the Twente region. The aeolian deposits considered here date from the Last Glacial Maximum (approximately 22 ka) to the start of the Belling Interstadial at 14.7 ka.
A major event in this period is the formation of a cryoturbation level caused by permafrost degradation, overlain by an erosional hiatus dated between 21 and 17 ka. Both features are attributed to a period of warmer and moister climate, causing permafrost degradation and erosion by surficial runoff. Thereafter aeolian activity prevailed under relatively arid conditions. A deflation surface was formed, the Beuningen Gravel Bed. This deflation surface is present in many Weichselian sections in the Netherlands and the adjacent parts of Belgium and Germany. The deflation occurred concurrently with deposition of coversand at other places.
The morphology of the coversand-landscape in the Dinkel valley was controlled by the relief of the pre-existing floodplain and the wind pattern. Coversand ridges consisting of low dunes accumulated near the margins of the active channel belt. Relatively thick sand sheets occur in the leesides of the ridges, thin sand sheets are found at greater distance.
Mainly westerly sand-transporting winds operated during winter and summer. In winter aeolian deposition occurred by frequent and strong easterly winds also. On the smallest, local scale, the pattern of deposition was determined by the topography and moisture of the receiving surface.
Coversand deposition came to an end with the formation of a sand sheet under relatively warm and less arid conditions. Coversand deposition continued into the Belling Interstadial; colonization of the coversand surface by vegetation probably has been delayed by nutrient-poor conditions.
Ordinary least square is the common way to estimate linear regression models. When inputs are correlated or when they are too numerous, regression methods using derived inputs directions or shrinkage methods can be efficient alternatives. Methods using derived inputs directions build new uncorrelated variables as linear combination of the initial inputs, whereas shrinkage methods introduce regularization and variable selection by penalizing the usual least square criterion. Both kinds of methods are presented and illustrated thanks to the R software on an astronomical dataset.
To determine the prevalence of thyroid malignancy in the first UK case series of patients with incidentally detected thyroid lesions on 18F-fluorodeoxyglucose positron emission tomography imaging.
A total of 235 patients were evaluated with 18F-fluorodeoxyglucose positron emission tomography imaging. Incidental focal uptake in the thyroid gland was identified in nine patients (3.8 per cent). A retrospective review of their case notes was conducted.
The rate of malignancy was 55 per cent. The mean and standard deviation of the maximum standardised uptake value was 13.1 ± 7.3 in those patients with malignancy and a nodule identified as positive on positron emission tomography. This value was 2.8 ± 1.2 in those patients without malignancy but with a nodule identified as positive on positron emission tomography (p = 0.01). A palpable thyroid nodule was more likely in those with malignant lesions (p = 0.14).
The prevalence of incidental thyroid lesions found on 18F-fluorodeoxyglucose positron emission tomography in patients with other primary malignancies is low, but the incidence of malignancy in these patients is high. Patients with a palpable thyroid nodule, focal uptake on 18F-fluorodeoxyglucose positron emission tomography and an increased maximum standardised uptake value require further investigation.
Dietary glutamine (Gln) supplementation improves intestinal function in several stressful conditions. Therefore, in the present study, the effects of dietary Gln supplementation on the core body temperature (Tcore), bacterial translocation (BT) and intestinal permeability of mice subjected to acute heat stress were evaluated. Male Swiss mice (4 weeks old) were implanted with an abdominal temperature sensor and randomly assigned to one of the following groups fed isoenergetic and isoproteic diets for 7 d before the experimental trials: group fed the standard AIN-93G diet and exposed to a high ambient temperature (39°C) for 2 h (H-NS); group fed the AIN-93G diet supplemented with l-Gln and exposed to a high temperature (H-Gln); group fed the standard AIN-93G diet and not exposed to a high temperature (control, C-NS). Mice were orally administered diethylenetriaminepentaacetic acid radiolabelled with technetium (99mTc) for the assessment of intestinal permeability or 99mTc-Escherichia coli for the assessment of BT. Heat exposure increased Tcore (approximately 41°C during the experimental trial), intestinal permeability and BT to the blood and liver (3 h after the experimental trial) in mice from the H-NS group relative to those from the C-NS group. Dietary Gln supplementation attenuated hyperthermia and prevented the increases in intestinal permeability and BT induced by heat exposure. No correlations were observed between the improvements in gastrointestinal function and the attenuation of hyperthermia by Gln. Our findings indicate that dietary Gln supplementation preserved the integrity of the intestinal barrier and reduced the severity of hyperthermia during heat exposure. The findings also indicate that these Gln-mediated effects occurred through independent mechanisms.
The efficiency of thin-film solar cells using a-Si:H is limited by the decrease in a-Si:H layer optical path length and its poor light absorption at red and NIR wavelengths. Metal NP such as Au have been shown to increase the absorption in the active material and then cell performances, by exhibiting localized surface plasmon (LSP) resonances. Our work’s goal is to understand NP influence in such cells, to perform an optimal structure by increasing the amount of light absorbed within the cell using NP scattering and luminescence. Modeling based on Mie theory is first carried out using bulk Palik data for Au spheres with various diameters and refractive medium indexes. Using modeling parameters, Au layers were deposited on glass and SnO2 substrates respectively by thermal evaporation in vacuum and sputtering, followed by thermal annealing (200 ∼ 500°C) in order to promote the NP growth. MEB pictures show quasispherical Au NP shape with a mean size of 150nm. This diameter range switches extinction of NP in scattering regime. Annealing temperature (T) strongly affects the NP morphology. Surface coverage decreases and sphericity appears to increase with T. UV-Visible spectroscopy displays distinct LSP resonances around 600nm after annealing with a red shift while T increases.