1,849 research outputs found
The inter-relation between policy and practice for transitions from hospital to home: An ethnographic case study in England’s National Health Service
© 2014 Shaw et al; licensee BioMed Central Ltd.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.No abstract available (poster presentation)
Ferromagnetic 0-pi Junctions as Classical Spins
The ground state of highly damped PdNi based 0-pi ferromagnetic Josephson
junctions shows a spontaneous half quantum vortex, sustained by a supercurrent
of undetermined sign. This supercurrent flows in the electrode of a Josephson
junction used as a detector and produces a phi(0)/4 shift in its magnetic
diffraction pattern. We have measured the statistics of the positive or
negative sign shift occurring at the superconducting transition of such a
junction. The randomness of the shift sign, the reproducibility of its
magnitude and the possibility of achieving exact flux compensation upon field
cooling: all these features show that 0-pi junctions behave as classical spins,
just as magnetic nanoparticles with uniaxial anisotropy.Comment: 4 pages, 4 figure
Thermal shot noise in top-gated single carbon nanotube field effect transistors
The high-frequency transconductance and current noise of top-gated single
carbon nanotube transistors have been measured and used to investigate hot
electron effects in one-dimensional transistors. Results are in good agreement
with a theory of 1-dimensional nano-transistor. In particular the prediction of
a large transconductance correction to the Johnson-Nyquist thermal noise
formula is confirmed experimentally. Experiment shows that nanotube transistors
can be used as fast charge detectors for quantum coherent electronics with a
resolution of in the 0.2- band.Comment: 3 pages, 4 figure
Shot noise in carbon nanotube based Fabry-Perot interferometers
We report on shot noise measurements in carbon nanotube based Fabry-Perot
electronic interferometers. As a consequence of quantum interferences, the
noise power spectral density oscillates as a function of the voltage applied to
the gate electrode. The quantum shot noise theory accounts for the data
quantitatively. It allows to confirm the existence of two nearly degenerate
orbitals. At resonance, the transmission of the nanotube approaches unity, and
the nanotube becomes noiseless, as observed in quantum point contacts. In this
weak backscattering regime, the dependence of the noise on the backscattering
current is found weaker than expected, pointing either to electron-electron
interactions or to weak decoherence
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Prediction of Treatment Response to Neoadjuvant Chemotherapy for Breast Cancer via Early Changes in Tumor Heterogeneity Captured by DCE-MRI Registration.
We analyzed DCE-MR images from 132 women with locally advanced breast cancer from the I-SPY1 trial to evaluate changes of intra-tumor heterogeneity for augmenting early prediction of pathologic complete response (pCR) and recurrence-free survival (RFS) after neoadjuvant chemotherapy (NAC). Utilizing image registration, voxel-wise changes including tumor deformations and changes in DCE-MRI kinetic features were computed to characterize heterogeneous changes within the tumor. Using five-fold cross-validation, logistic regression and Cox regression were performed to model pCR and RFS, respectively. The extracted imaging features were evaluated in augmenting established predictors, including functional tumor volume (FTV) and histopathologic and demographic factors, using the area under the curve (AUC) and the C-statistic as performance measures. The extracted voxel-wise features were also compared to analogous conventional aggregated features to evaluate the potential advantage of voxel-wise analysis. Voxel-wise features improved prediction of pCR (AUC = 0.78 (±0.03) vs 0.71 (±0.04), p < 0.05 and RFS (C-statistic = 0.76 ( ± 0.05), vs 0.63 ( ± 0.01)), p < 0.05, while models based on analogous aggregate imaging features did not show appreciable performance changes (p > 0.05). Furthermore, all selected voxel-wise features demonstrated significant association with outcome (p < 0.05). Thus, precise measures of voxel-wise changes in tumor heterogeneity extracted from registered DCE-MRI scans can improve early prediction of neoadjuvant treatment outcomes in locally advanced breast cancer
Planar SFS Josephson Junctions Made by Focused Ion Beam Etching
Superconductor-Ferromagnet-Superconductor (S-F-S) Josephson junctions were
fabricated by making a narrow cut through a S-F double layer using direct
writing by Focused Ion Beam (FIB). Due to a high resolution (spot size smaller
than 10 nm) of FIB, junctions with a small separation between superconducting
electrodes ( 30 nm) can be made. Such a short distance is sufficient for
achieving a considerable proximity coupling through a diluted CuNi ferromagnet.
We have successfully fabricated and studied S-F-S (Nb-CuNi-Nb) and S-S'-S
(Nb-Nb/CuNi-Nb) junctions. Junctions exhibit clear Fraunhofer modulation of the
critical current as a function of magnetic field, indicating good uniformity of
the cut. By changing the depth of the cut, junctions with the product
ranging from 0.5 mV to V were fabricated.Comment: 5 pages, 5 figures, presentation at EUCAS-2003, to be published in
Physica
Congenital erythropoietic porphyria associated with myelodysplasia presenting in a 72-year-old man: report of a case and review of the literature
Congenital erythropoietic porphyria (CEP) is a rare autosomal recessive disease owing to the deficient activity of uroporphyrinogen III synthase, the fourth enzyme in the porphyrin–haem synthetic pathway. Of the porphyrias, it is the most mutilating type, usually presenting early in life. To date, 12 documented cases of adult onset CEP have been reported. We report the second oldest documented patient with late onset CEP with incidental findings of thrombocytopenia and myelodysplasia with bone-marrow sideroblasts. We further discuss several current and future treatment options for this therapeutically challenging disease.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73760/1/j.1365-2133.2003.05040.x.pd
Conserved spin and orbital phase along carbon nanotubes connected with multiple ferromagnetic contacts
We report on spin dependent transport measurements in carbon nanotubes based
multi-terminal circuits. We observe a gate-controlled spin signal in non-local
voltages and an anomalous conductance spin signal, which reveal that both the
spin and the orbital phase can be conserved along carbon nanotubes with
multiple ferromagnetic contacts. This paves the way for spintronics devices
exploiting both these quantum mechanical degrees of freedom on the same
footing.Comment: 8 pages - minor differences with published versio
Improved NASA-ANOPP Noise Prediction Computer Code for Advanced Subsonic Propulsion Systems
Recent experience using ANOPP to predict turbofan engine flyover noise suggests that it over-predicts overall EPNL by a significant amount. An improvement in this prediction method is desired for system optimization and assessment studies of advanced UHB engines. An assessment of the ANOPP fan inlet, fan exhaust, jet, combustor, and turbine noise prediction methods is made using static engine component noise data from the CF6-8OC2, E(3), and QCSEE turbofan engines. It is shown that the ANOPP prediction results are generally higher than the measured GE data, and that the inlet noise prediction method (Heidmann method) is the most significant source of this overprediction. Fan noise spectral comparisons show that improvements to the fan tone, broadband, and combination tone noise models are required to yield results that more closely simulate the GE data. Suggested changes that yield improved fan noise predictions but preserve the Heidmann model structure are identified and described. These changes are based on the sets of engine data mentioned, as well as some CFM56 engine data that was used to expand the combination tone noise database. It should be noted that the recommended changes are based on an analysis of engines that are limited to single stage fans with design tip relative Mach numbers greater than one
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