6,667 research outputs found
Prognostic value of troponins in acute coronary syndrome depends upon patient age
Peer reviewedPostprin
Conformational Mechanics of Polymer Adsorption Transitions at Attractive Substrates
Conformational phases of a semiflexible off-lattice homopolymer model near an
attractive substrate are investigated by means of multicanonical computer
simulations. In our polymer-substrate model, nonbonded pairs of monomers as
well as monomers and the substrate interact via attractive van der Waals
forces. To characterize conformational phases of this hybrid system, we analyze
thermal fluctuations of energetic and structural quantities, as well as
adequate docking parameters. Introducing a solvent parameter related to the
strength of the surface attraction, we construct and discuss the
solubility-temperature phase diagram. Apart from the main phases of adsorbed
and desorbed conformations, we identify several other phase transitions such as
the freezing transition between energy-dominated crystalline low-temperature
structures and globular entropy-dominated conformations.Comment: 13 pages, 15 figure
Quantitative analysis of shadow X-ray Magnetic Circular Dichroism Photo-Emission Electron Microscopy
Shadow X-ray Magnetic Circular Dichroism Photo-Emission Electron Microscopy
(XMCD-PEEM) is a recent technique, in which the photon intensity in the shadow
of an object lying on a surface, may be used to gather information about the
three-dimensional magnetization texture inside the object. Our purpose here is
to lay the basis of a quantitative analysis of this technique. We first discuss
the principle and implementation of a method to simulate the contrast expected
from an arbitrary micromagnetic state. Text book examples and successful
comparison with experiments are then given. Instrumental settings are finally
discussed, having an impact on the contrast and spatial resolution : photon
energy, microscope extraction voltage and plane of focus, microscope background
level, electric-field related distortion of three-dimensional objects, Fresnel
diffraction or photon scattering
Economic inequalities in burden of illness, diagnosis and treatment of five long-term conditions in England: panel study
We compared the distribution by wealth of self-reported illness burden (estimated from validated scales, biomarker and reported symptoms) for angina, cataract, depression, diabetes and osteoarthritis, with the distribution of self-reported medical diagnosis and treatment. We aimed to determine if the greater illness burden borne by poorer participants was matched by appropriately higher levels of diagnosis and treatment
Casimir Effect in the Presence of Minimal Lengths
It is expected that the implementation of minimal length in quantum models
leads to a consequent lowering of Planck's scale. In this paper, using the
quantum model with minimal length of Kempf et al \cite{kempf0}, we examine the
effect of the minimal length on the Casimir force between parallel plates.Comment: 10 pages, 2 figure
Development and applications of the Gas Electron Multiplier
The Gas Electron Multiplier (GEM) has been recently developed to cope with the severe requirements of high luminosity particle physics experimentation. With excellent position accuracy and very high rate capability, GEM devices are robust and easy to manufacture. The possibility of cascading two or more multipliers permits to achieve larger gains and more stable operation. We discuss major performances of the new detectors, particularly in view of possible use for high rate portal imaging and medical diagnostics
Development of large area resistive electrodes for ATLAS NSW Micromegas
Micromegas with resistive anodes will be used for the NSW upgrades of the ATLAS experiment at LHC. Resistive electrodes are used in MPGD devices to prevent sparks in high-rate operation. Large-area resistive electrodes for Micromegas have been developed using two different technologies: screen printing and carbon sputtering. The maximum resistive foil size is 45 × 220 cm with a printed pattern of 425-μm pitch strips. These technologies are also suitable for mass production. Prototypes of a production model series have been successfully produced. In this paper, we report the development, the production status, and the test results of resistive Micromegas
Disordered quantum wires: microscopic origins of the DMPK theory and Ohm's law
We study the electronic transport properties of the Anderson model on a
strip, modeling a quasi one-dimensional disordered quantum wire. In the
literature, the standard description of such wires is via random matrix theory
(RMT). Our objective is to firmly relate this theory to a microscopic model. We
correct and extend previous work (arXiv:0912.1574) on the same topic. In
particular, we obtain through a physically motivated scaling limit an ensemble
of random matrices that is close to, but not identical to the standard transfer
matrix ensembles (sometimes called TOE, TUE), corresponding to the Dyson
symmetry classes \beta=1,2. In the \beta=2 class, the resulting conductance is
the same as the one from the ideal ensemble, i.e.\ from TUE. In the \beta=1
class, we find a deviation from TOE. It remains to be seen whether or not this
deviation vanishes in a thick-wire limit, which is the experimentally relevant
regime. For the ideal ensembles, we also prove Ohm's law for all symmetry
classes, making mathematically precise a moment expansion by Mello and Stone.
This proof bypasses the explicit but intricate solution methods that underlie
most previous results.Comment: Corrects and extends arXiv:0912.157
Review of the Neotropical millipede genus Pycnotropis CARL, 1914 (Diplopoda, Polydesmida, Aphelidesmidae)
A review of Pycnotropis is presented, with the description of 14 new species: P. goeldii n.sp., P. madeira n.sp., P. sigma n.sp. and P. urucu n.sp., all from Brazil, P. carli n.sp. from Ecuador, P. curvata n.sp., P. falcata n.sp., P. jeekeli n.sp., P. pallidicornis n.sp., P. similis n.sp., P. subfalcata n. sp., P. unapi n.sp., P. torresi n.sp. and P. zumbii n.sp., all from Peru. P. acuticollis (ATTEMS, 1899), is redescribed upon the holotype from Brazil. Based on abundant strictly topotypic material, P. tida (CHAMBERLIN, l94l), is considered as a subjective senior synonym of P. epiclysmus HOFFMAN, 1995 (syn.n.). A key has been compiled to all 26 species of this diverse genus, with notes on its distribution
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