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This paper sets up the foundations for derived algebraic geometry, Goerss–Hopkins obstruction theory, and the construction of commutative ring spectra in the abstract setting of operadic algebras in symmetric spectra in an (essentially) arbitrary model category. We show that one can do derived algebraic geometry a la Toën–Vezzosi in an abstract category of spectra. We also answer in the affirmative a question of Goerss and Hopkins by showing that the obstruction theory for operadic algebras in spectra can be done in the generality of spectra in an (essentially) arbitrary model category. We construct strictly commutative simplicial ring spectra representing a given cohomology theory and illustrate this with a strictly commutative motivic ring spectrum representing higher order products on Deligne cohomology. These results are obtained by first establishing Smith’s stable positive model structure for abstract spectra and then showing that this category of spectra possesses excellent model-theoretic properties: we show that all colored symmetric operads in symmetric spectra valued in a symmetric monoidal model category are admissible, i.e., algebras over such operads carry a model structure. This generalizes the known model structures on commutative ring spectra and
-ring spectra in simplicial sets or motivic spaces. We also show that any weak equivalence of operads in spectra gives rise to a Quillen equivalence of their categories of algebras. For example, this extends the familiar strictification of
-rings to commutative rings in a broad class of spectra, including motivic spectra. We finally show that operadic algebras in Quillen equivalent categories of spectra are again Quillen equivalent. This paper is also available at arXiv:1410.5699v2.
Various ontology visualization tools using different visualization methods exist and new ones are being developed every year. The goal of this paper is to follow up on previous surveys with an updated classification of ontology visualization methods and a comprehensive survey of available tools. The tools are analyzed for the used visualization methods, interaction techniques and supported ontology constructs. It shows that most of the tools apply two-dimensional node-link visualizations with a focus on class hierarchies. Color and shape are used with little variation, support for constructs introduced with version 2 of the OWL Web Ontology Language is limited, and it often remains vague what tasks and use cases are supported by the visualizations. Major challenges are the limited maturity and usability of many of the tools as well as providing an overview of large ontologies while also showing details on demand. We see a high demand for a universal ontology visualization framework implementing a core set of visual and interactive features that can be extended and customized to respective use cases.
Two-step crystallization process based on a low-Pb-content seed layer is proposed to form PZT films by the chemical solution deposition. The first crystallization step was performed after the deposition from precursor solutions with 0 and 5 wt% Pb excess, which provides a low nucleation rate and the strong perovskite (111) orientation. The bulk film was obtained from solutions with a 30 wt% Pb excess, which ensures a high growth rate and eliminates formation of pyrochlore residuals. Some films with a fixed Pb excess were prepared for comparison. It is shown that the low-Pb-content seed layer can sufficiently enhance the texture of perovskite (111) grains thus providing the highest polarization magnitudes as compared to films prepared with the fixed Pb content. The lead content and the crystallization of the seed layer are found to affect the grain-boundary conduction, which, in turn, influences the polarization dependence of transient currents.
The activity of intracellular proteolytic enzymes was studied in Atlantic salmon (Salmo salar L.) fingerlings (0+) after hatching from spawning nests and dispersal in the Varzuga River main stem and its Pyatka tributary (Kola Peninsula, White Sea Basin). The study focused on calcium-dependent cytosolic proteinases (µ- and m-calpains), lysosomal proteinases (cathepsins В and D) and collagenase, and determined the free/protein-bound hydroxyproline ratio, which portrays collagenolytic activity. Compared to fingerlings from the Varzuga main stem, the intracellular proteolytic enzyme activity of cysteine proteinase and collagenase was higher in fingerlings from the Pyatka tributary, where current velocities and food availability were higher. These results indicate that there is a higher rate of intracellular protein metabolism in the juveniles from this phenotypic group.
The IAU Commission 4 Working Group on Standardizing Access to Ephemerides recommends the use of the Spacecraft and Planet Kernel (SPK) format to provide a uniform format for the position ephemerides of planets and other natural solar system bodies, and the use of the Planetary Constants Kernel (PCK) for the orientation of these bodies. These formats are used by the SPICE system, developed by the Navigation and Ancillary Information Facility of NASA's Jet Propulsion Laboratory. The working group's final report is currently undergoing final preparations for publication. A long version of this report will be available at the IAU Commission 4: Ephemerides (or its successor) web site. This long version will contain a full description of that portion of the SPK and PCK formats required to duplicate these file types for this application.
In many practical situations sample sizes are not sufficiently large
and estimators based on such samples may not be satisfactory in
terms of their variances. At the same time it is not unusual that
some auxiliary information about the parameters of interest is
available. This paper considers a method of using auxiliary
information for improving properties of the estimators based on a
current sample only. In particular, it is assumed that the
information is available as a number of estimates based on samples
obtained from some other mutually independent data sources. This
method uses the fact that there is a correlation effect between
estimators based on the current sample and auxiliary information
from other sources. If variance covariance matrices of vectors of
estimators used in the estimating procedure are known, this method
produces more efficient estimates in terms of their variances
compared to the estimates based on the current sample only. If these
variance-covariance matrices are not known, their consistent
estimates can be used as well such that the large sample properties
of the method remain unchangeable. This approach allows to improve
statistical properties of many standard estimators such as an
empirical cumulative distribution function, empirical characteristic
function, and Nelson-Aalen cumulative hazard estimator.
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