1,763 research outputs found
Identifying Myotis Species Using Geometric Morphometrics and its Implications for the Fossil Record and Conservation
Dentaries of the 6 species of Myotis that occur in the eastern United States were analyzed using landmark-based geometric morphometrics. The species could be distinguished with a high degree of accuracy. Evidence was found of a phylogenetic signal in the morphology of the Neotropical and Nearctic Myotis sub-clades. There is also evidence of convergence in the morphology of the dentary among Myotis species that feed primarily by gleaning. When analyzed together there was no evidence of sexual dimorphism among the 6 eastern U.S. Myotis, but when analyzed individually some dimorphism may be present. A sample of fossil Myotis of unknown species from Bat Cave, Kentucky, was analyzed in an attempt to identify the specimens to species. Results indicate that Myotis austroriparius and M. sodalis predominate the sample, possibly with smaller numbers of M. grisescens and M. leibii. This study demonstrates the ability to differentiate Myotis taxa from historic and prehistoric sites and provides a tool for researchers to better understand and potentially conserve these species
The On The Fly Imaging Technique
The On-The-Fly (OTF) imaging technique enables single-dish radio telescopes
to construct images of small areas of the sky with greater efficiency and
accuracy. This paper describes the practical application of the OTF imaging
technique. By way of example the implementation of the OTF imaging technique at
the NRAO 12 Meter Telescope is described. Specific requirements for data
sampling, image formation, and Doppler correction are discussed.Comment: 10 pages, 13 figures, accepted A&
Non classical effects in planar waveguides
The quantum description of light propagation inside a planar waveguide is given. In particular, the description describes the behavior of the field inside a directions coupler. Nonclassical effects are presented and discussed
Relational und dimensional: heuristische Dimensionen in der Situationsanalyse am Beispiel von Care-Praktiken und ihrer Materialität
Die Berücksichtigung von Materialität ist ein wesentlicher Bestandteil der Sozialwissenschaften des 21. Jahrhunderts. Für die empirische Sozialforschung ergeben sich daraus methodologische und methodische Herausforderungen, insbesondere in Bezug auf nicht-menschliche Akteur*innen und deren Körperlichkeit. Dies erfordert spezifische Analyseverfahren. Die Situationsanalyse mit ihrer Fokusverschiebung auf die Relationalität von heterogenen Akteur*innen, die eine Handlungssituation generieren, bietet dazu eine entsprechende Möglichkeit. Im vorliegenden Beitrag gehen wir auf der Basis zweier empirischer Projekte zu Care-Praktiken im medizinischen Bereich der Frage der Multidimensionalität von materiellen Beziehungen nach. Die Beispiele beziehen sich zum einen auf das Einschläfern von Pferden in der Tiermedizin und zum anderen auf automatisierte Technologien bei der Behandlung von Typ-1-Diabetes. Im Zentrum der Analyse steht die Materialität des Beziehungsgeflechts. Wir schlagen vor, den Werkzeugkasten der Situationsanalyse um ein dimensionalisierendes Relations-Mapping zu erweitern, indem die Beziehungen zwischen Elementen in Dimensionen unterteilt werden. In den Beispielen nutzen wir eine Dimensionalisierung, bei der wir uns an der Care-Theorie orientieren. Die Verwendung von unterschiedlichen Farben im Mapping macht die Multidimensionalität der Situation erst sichtbar und ermöglicht es, der Komplexität der materiellen und körperlichen Beziehungen analytisch mehr Raum zu geben.The consideration of materiality is an essential component of the social sciences of the 21st century. For empirical social research, this poses methodological challenges, especially concerning non-human actors and their corporeality. Therefore, specific analytical strategies are required. Situational analysis, focusing on the relationality of heterogeneous actors generating a situation, offers one such possibility. In this article, we explore the multidimensionality and relationality of materiality through two empirical projects about care practices in the medical field. Examples are euthanizing of horses in veterinary medicine and automated technologies in managing type 1 diabetes. In the analysis, we focus on the materiality of the relational network. We propose to extend the situation analysis toolbox by adding dimensionalizing relational mapping, where we categorize the relations between elements into dimensions. In the examples, we use a dimensionalization inspired by care theory. The use of different colors in the mapping practice highlights the multidimensionality of the situation and gives more analytical space to the complexity of the material and embodied connections
Neutron spectra measurement and calculations using data libraries CIELO, JEFF-3.2 and ENDF/B-VII.1 in iron benchmark assemblies
Transcript of The Dory Derby Accident
This story is an excerpt from a longer interview that was collected as part of the Launching through the Surf: The Dory Fleet of Pacific City project. In this story, Don Grotjohn recounts an accident that occurred during a Dory Derby competition
Optimally squeezed spin states
We consider optimally spin-squeezed states that maximize the sensitivity of
the Ramsey spectroscopy, and for which the signal to noise ratio scales as the
number of particles . Using the variational principle we prove that these
states are eigensolutions of the Hamiltonian
and that, for large , the states become equivalent to the quadrature
squeezed states of the harmonic oscillator. We present numerical results that
illustrate the validity of the equivalence
Astrometry and geodesy with radio interferometry: experiments, models, results
Summarizes current status of radio interferometry at radio frequencies
between Earth-based receivers, for astrometric and geodetic applications.
Emphasizes theoretical models of VLBI observables that are required to extract
results at the present accuracy levels of 1 cm and 1 nanoradian. Highlights the
achievements of VLBI during the past two decades in reference frames, Earth
orientation, atmospheric effects on microwave propagation, and relativity.Comment: 83 pages, 19 Postscript figures. To be published in Rev. Mod. Phys.,
Vol. 70, Oct. 199
The contribution of star-forming galaxies to the cosmic radio background
Recent measurements of the temperature of the sky in the radio band, combined
with literature data, have convincingly shown the existence of a cosmic radio
background with an amplitude of K at 1 GHz and a spectral energy
distribution that is well described by a power law with index . The origin of this signal remains elusive, and it has been speculated
that it could be dominated by the contribution of star-forming galaxies at high
redshift \change{if the far infrared-radio correlation evolved} in time.
\change{We fit observational data from several different experiments by the
relation with and
and estimate the total radio emission of the whole
galaxy population at any given redshift from the cosmic star formation rate
density at that redshift. It is found that} star-forming galaxies can only
account for 13 percent of the observed intensity of the cosmic radio
background.Comment: 5 pages, 3 figure
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