97,326 research outputs found
Diet of Two Large Sympatric Teleosts, the Ling (Genypterus blacodes) and Hake (Merluccius australis)
Ling and hake are tertiary consumers, and as a result both may have an important structuring role in marine communities. The diets of 2064 ling and 913 hake from Chatham Rise, New Zealand, were determined from examination of stomach contents. Ling was a benthic generalist, and hake a demersal piscivore. The diet of ling was characterised by benthic crustaceans, mainly Munida gracilis and Metanephrops challengeri, and demersal fishes, mainly Macrourids and scavenged offal from fishing vessels. The diet of hake was characterised by teleost fishes, mainly macrourids and merlucciids. Multivariate analyses using distance-based linear models found the most important predictors of diet variability were depth, fish length, and vessel type (whether the sample was collected from a commercial or research vessel) for ling, and fish length and vessel type for hake. There was no interspecific predation between ling and hake, and resource competition was largely restricted to macrourid prey, although the dominant macrourid species predated by ling and hake were different. Cluster analysis of average diet of intraspecific groups of ling and hake confirmed the persistent diet separation. Although size is a central factor in determining ecological processes, similar sized ling and hake had distinctly different foraging ecology, and therefore could influence the ecosystem in different ways, and be unequally affected by ecosystem fluctuations
La lingüÃstica i la construcció de la teoria del llenguatge
Les claus de la lingüística d'avu
Ontology-Based Data Access and Integration
An ontology-based data integration (OBDI) system is an information management system consisting of three components: an ontology, a set of data sources, and the mapping between the two. The ontology is a conceptual, formal description of the domain of interest to a given organization (or a community of users), expressed in terms of relevant concepts, attributes of concepts, relationships between concepts, and logical assertions characterizing the domain knowledge. The data sources are the repositories accessible by the organization where data concerning the domain are stored. In the general case, such repositories are numerous, heterogeneous, each one managed and maintained independently from the others. The mapping is a precise specification of the correspondence between the data contained in the data sources and the elements of the ontology. The main purpose of an OBDI system is to allow information consumers to query the data using the elements in the ontology as predicates.
In the special case where the organization manages a single data source, the term ontology-based data access (ODBA) system is used
Comment on the Coupling of Zero Sound to the Modes of He-B
Features in the zero sound attenuation near the pair-breaking edge in
superfluid He-B have been observed in large magnetic fields. Schopohl and
Tewordt [{\sl J. Low Temp. Phys.} {\bf 57}, 601 (1984)] claim that the order-parameter collective modes couple to zero sound as a result of
the distortion of the equilibrium order parameter by a magnetic field; they
identify the new features with these modes. However, we show that, when the
effect of gap distortion on the collective modes is properly taken into
account, the collective mode equations of Schopohl and Tewordt yield no direct
coupling of zero sound to the modes. Thus, the identification of the
absorption features reported by Ling, Saunders and Dobbs [{\sl Phys. Rev.
Lett.} {\bf 59}, 461 (1987)] near the pair-breaking edge with the modes
is not clearly established.Comment: 6 pages (Tex with jnl.tex
WebProt\'eg\'e: A Cloud-Based Ontology Editor
We present WebProt\'eg\'e, a tool to develop ontologies represented in the
Web Ontology Language (OWL). WebProt\'eg\'e is a cloud-based application that
allows users to collaboratively edit OWL ontologies, and it is available for
use at https://webprotege.stanford.edu. WebProt\'ege\'e currently hosts more
than 68,000 OWL ontology projects and has over 50,000 user accounts. In this
paper, we detail the main new features of the latest version of WebProt\'eg\'e
Using Social Media to Promote STEM Education: Matching College Students with Role Models
STEM (Science, Technology, Engineering, and Mathematics) fields have become
increasingly central to U.S. economic competitiveness and growth. The shortage
in the STEM workforce has brought promoting STEM education upfront. The rapid
growth of social media usage provides a unique opportunity to predict users'
real-life identities and interests from online texts and photos. In this paper,
we propose an innovative approach by leveraging social media to promote STEM
education: matching Twitter college student users with diverse LinkedIn STEM
professionals using a ranking algorithm based on the similarities of their
demographics and interests. We share the belief that increasing STEM presence
in the form of introducing career role models who share similar interests and
demographics will inspire students to develop interests in STEM related fields
and emulate their models. Our evaluation on 2,000 real college students
demonstrated the accuracy of our ranking algorithm. We also design a novel
implementation that recommends matched role models to the students.Comment: 16 pages, 8 figures, accepted by ECML/PKDD 2016, Industrial Trac
Acceptance dependence of fluctuation measures near the QCD critical point
We argue that a crucial determinant of the acceptance dependence of
fluctuation measures in heavy-ion collisions is the range of correlations in
the momentum space, e.g., in rapidity, . The value of
for critical thermal fluctuations is determined by
the thermal rapidity spread of the particles at freezeout, and has little to do
with position space correlations, even near the critical point where the
spatial correlation length becomes as large as fm (this is in
contrast to the magnitudes of the cumulants, which are sensitive to ).
When the acceptance window is large, , the
cumulants of a given particle multiplicity, , scale linearly with
, or mean multiplicity in acceptance, , and
cumulant ratios are acceptance independent. While in the opposite regime,
, the factorial cumulants, ,
scale as , or . We demonstrate this general
behavior quantitatively in a model for critical point fluctuations, which also
shows that the dependence on transverse momentum acceptance is very
significant. We conclude that extension of rapidity coverage proposed by STAR
should significantly increase the magnitude of the critical point fluctuation
signatures.Comment: 9 pages, 4 figures, references adde
Magnetic and orbital order in overdoped bilayer manganites
The magnetic and orbital orders for the bilayer manganites in the doping
region have been investigated from a model that incorporates the
two orbitals at each Mn site, the inter-orbital Coulomb interaction and
lattice distortions. The usual double exchange operates via the orbitals.
It is shown that such a model reproduces much of the phase diagram recently
obtained for the bilayer systems in this range of doping. The C-type phase with
() spin order seen by Ling et al. appears as a natural consequence
of the layered geometry and is stabilised by the static distortions of the
system. The orbital order is shown to drive the magnetic order while the
anisotropic hopping across the orbitals, layered nature of the underlying
structure and associated static distortions largely determine the orbital
arrangements.Comment: 8 pages, 5 figure
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