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Cloud information content analysis of multi-angular measurements in the oxygen A-band: application to 3MI and MSPI
The vertical distribution of cloud cover has a significant impact on a large number of meteorological and climatic processes. Cloud top altitude and cloud geometrical thickness are then essential. Previous studies established the possibility of retrieving those parameters from multi-angular oxygen A-band measurements. Here we perform a study and comparison of the performances of future instruments. The 3MI (Multi-angle, Multi-channel and Multi-polarization Imager) instrument developed by EUMETSAT, which is an extension of the POLDER/PARASOL instrument, and MSPI (Multi-angles Spectro-Polarimetric Imager) develoloped by NASA's Jet Propulsion Laboratory will measure total and polarized light reflected by the Earth's atmosphere–surface system in several spectral bands (from UV to SWIR) and several viewing geometries. Those instruments should provide opportunities to observe the links between the cloud structures and the anisotropy of the reflected solar radiation into space. Specific algorithms will need be developed in order to take advantage of the new capabilities of this instrument. However, prior to this effort, we need to understand, through a theoretical Shannon information content analysis, the limits and advantages of these new instruments for retrieving liquid and ice cloud properties, and especially, in this study, the amount of information coming from the A-Band channel on the cloud top altitude (CTOP) and geometrical thickness (CGT). We compare the information content of 3MI A-Band in two configurations and that of MSPI. Quantitative information content estimates show that the retrieval of CTOP with a high accuracy is possible in almost all cases investigated. The retrieval of CGT seems less easy but possible for optically thick clouds above a black surface, at least when CGT > 1–2 km
New primary renal diagnosis codes for the ERA-EDTA
The European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) Registry has produced a new set of primary renal diagnosis (PRD) codes that are intended for use by affiliated registries. It is designed specifically for use in renal centres and registries but is aligned with international coding standards supported by the WHO (International Classification of Diseases) and the International Health Terminology Standards Development Organization (SNOMED Clinical Terms). It is available as supplementary material to this paper and free on the internet for non-commercial, clinical, quality improvement and research use, and by agreement with the ERA-EDTA Registry for use by commercial organizations. Conversion between the old and the new PRD codes is possible. The new codes are very flexible and will be actively managed to keep them up-to-date and to ensure that renal medicine can remain at the forefront of the electronic revolution in medicine, epidemiology research and the use of decision support systems to improve the care of patients
Dissolution on Saturn's Moon Titan: A 3D Karst Landscape Evolution Model
Titan is an Earth-like world possessing a nitrogen-rich atmosphere covering a surface showing signs of lacustrine (lakes and depressions), fluvial (channels, valleys), aeolian (longitudinal dunes) activity. The chemistry implied in the geological processes is, however, strikingly different from that on Earth. Titan’s extremely cold environment (T ~ -180°C) only allows water to exist under the form of an icy “bedrock”. The presence of methane as the second major constituent in the atmosphere, as well as an active nitrogen-methane photochemistry, allows methane and ethane to drive a hydrocarbon cycle similar to the terrestrial hydrological cycle. A plethora of organic solids, more or less soluble in liquid hydrocarbons, is also produced in the atmosphere and can lead, by atmospheric sedimentation over geological timescales, to formation of some kind of organic geological sedimentary layer.
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Based on comparisons between Titan’s landscapes seen in the Cassini spacecraft data and terrestrial analogues, karstic-like dissolution and evaporitic crystallization have been suggested in various instances to take part in the landscape development on Titan. Dissolution has been invoked, for instance, for the development of the so-called “labyrinthic terrain”, located at high latitudes and resembling terrestrial cockpit or polygonal karst terrain. In this work, we aim at testing this hypothesis by comparing the natural landscapes visible in the Cassini/RADAR images of Titan’s surface, with those inferred from the use of a 3D Landscape Evolution Model (LEM) based on the Channel-Hillslope Integrated Landscape Development (CHILD), modified to include karstic dissolution as the major geological process. Digital Elevation Models (DEMs) are generated from an initial quasi-planar surface for a set of dissolution rates, diffusion coefficients (solute transport), and sink densities of the mesh. The landscape evolves over millions of years. Synthetic SAR images are generated from these DEMs in order to compare with Titan’s landforms seen in the actual SAR images and infer the possible thickness and degree of maturation of the Titan kars
Gravitational decays of heavy particles in large extra dimensions
In the framework of quantum gravity propagating in large extra dimensions, we
analyze the inclusive radiative emission of Kaluza-Klein spin-2 gravitons in
the two-fermions decays of massive gauge bosons, heavy quarks, Higgs bosons,
and in the two-massive gauge bosons decay of Higgs bosons. We provide
analytical expressions for the square modulus of amplitudes summed over
polarizations, and numerical results for the widths and branching ratios. The
corresponding decays in the Z, top quark, and Higgs boson sectors of the
standard model are analyzed in the light of present and future experiments.Comment: 29 pages, 4 figures, notation slightly changed, a few comments adde
Electroweak Radiative Corrections to Neutral-Current Drell-Yan Processes at Hadron Colliders
We calculate the complete electroweak O(alpha) corrections to pp, pbar p ->
l+l- X (l=e, mu) in the Standard Model of electroweak interactions. They
comprise weak and photonic virtual one-loop corrections as well as real photon
radiation to the parton-level processes q bar q -> gamma,Z -> l+l-. We study in
detail the effect of the radiative corrections on the l+l- invariant mass
distribution, the cross section in the Z boson resonance region, and on the
forward-backward asymmetry, A_FB, at the Fermilab Tevatron and the CERN Large
Hadron Collider. The weak corrections are found to increase the Z boson cross
section by about 1%, but have little effect on the forward-backward asymmetry
in the Z peak region. Threshold effects of the W box diagrams lead to
pronounced effects in A_FB at m(l+l-) approx 160 GeV which, however, will be
difficult to observe experimentally. At high di-lepton invariant masses, the
non-factorizable weak corrections are found to become large.Comment: Revtex3 file, 39 pages, 2 tables, 12 figure
Prospective evaluation of a new Aspergillus IgG EIA kit for the diagnosis of chronic and allergic pulmonary aspergillosis
International audienc
Top Quarks as a Window to String Resonances
We study the discovery potential of string resonances decaying to
final state at the LHC. We point out that top quark pair production is a
promising and an advantageous channel for studying such resonances, due to
their low Standard Model background and unique kinematics. We study the
invariant mass distribution and angular dependence of the top pair production
cross section via exchanges of string resonances. The mass ratios of these
resonances and the unusual angular distribution may help identify their
fundamental properties and distinguish them from other new physics. We find
that string resonances for a string scale below 4 TeV can be detected via the
channel, either from reconstructing the semi-leptonic
decay or recent techniques in identifying highly boosted tops.Comment: 22 pages, 6 figure
Ambient-aware continuous care through semantic context dissemination
Background: The ultimate ambient-intelligent care room contains numerous sensors and devices to monitor the patient, sense and adjust the environment and support the staff. This sensor-based approach results in a large amount of data, which can be processed by current and future applications, e. g., task management and alerting systems. Today, nurses are responsible for coordinating all these applications and supplied information, which reduces the added value and slows down the adoption rate. The aim of the presented research is the design of a pervasive and scalable framework that is able to optimize continuous care processes by intelligently reasoning on the large amount of heterogeneous care data.
Methods: The developed Ontology-based Care Platform (OCarePlatform) consists of modular components that perform a specific reasoning task. Consequently, they can easily be replicated and distributed. Complex reasoning is achieved by combining the results of different components. To ensure that the components only receive information, which is of interest to them at that time, they are able to dynamically generate and register filter rules with a Semantic Communication Bus (SCB). This SCB semantically filters all the heterogeneous care data according to the registered rules by using a continuous care ontology. The SCB can be distributed and a cache can be employed to ensure scalability.
Results: A prototype implementation is presented consisting of a new-generation nurse call system supported by a localization and a home automation component. The amount of data that is filtered and the performance of the SCB are evaluated by testing the prototype in a living lab. The delay introduced by processing the filter rules is negligible when 10 or fewer rules are registered.
Conclusions: The OCarePlatform allows disseminating relevant care data for the different applications and additionally supports composing complex applications from a set of smaller independent components. This way, the platform significantly reduces the amount of information that needs to be processed by the nurses. The delay resulting from processing the filter rules is linear in the amount of rules. Distributed deployment of the SCB and using a cache allows further improvement of these performance results
Infectious Disease Ontology
Technological developments have resulted in tremendous increases in the volume and diversity of the data and information that must be processed in the course of biomedical and clinical research and practice. Researchers are at the same time under ever greater pressure to share data and to take steps to ensure that data resources are interoperable. The use of ontologies to annotate data has proven successful in supporting these goals and in providing new possibilities for the automated processing of data and information. In this chapter, we describe different types of vocabulary resources and emphasize those features of formal ontologies that make them most useful for computational applications. We describe current uses of ontologies and discuss future goals for ontology-based computing, focusing on its use in the field of infectious diseases. We review the largest and most widely used vocabulary resources relevant to the study of infectious diseases and conclude with a description of the Infectious Disease Ontology (IDO) suite of interoperable ontology modules that together cover the entire infectious disease domain
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