73,695 research outputs found
Measurements of neutral vector resonance in Higgsless models at the LHC
In Higgsless models, new vector resonances appear to restore the unitarity of
the W_L W_L scattering amplitude without the Higgs boson. In the ideal
delocalized three site Higgsless model, one of large prodcution cross section
of the neutral vector resonance (Z') at the Large Hadron Collider is the
W-associated production, pp \to Z'W \to WWW. Although the dileptonic decay
channnel, l\nu l'\nu 'jj, is experimentally clean to search for the Z' signals,
it is difficult to reconstruct the Z' invariant mass due to the two neutrinos
in the final state. We study collider signatures of Z' using the
M_{T2}-Assisted On-Shell (MAOS) reconstruction of the missing neutrino momenta.
We show the prospect of the Z' mass determination in the channel, l\nu l'\nu
'jj, at the Large Hadron Collider.Comment: 16 pages, 6 figures, 5 tables; v2: references added, minor
corrections, version published in JHE
True Neutrality as a New Type of Flavour
A classification of leptonic currents with respect to C-operation requires
the separation of elementary particles into the two classes of vector C-even
and axial-vector C-odd character. Their nature has been created so that to each
type of lepton corresponds a kind of neutrino. Such pairs are united in
families of a different C-parity. Unlike the neutrino of a vector type, any
C-noninvariant Dirac neutrino must have his Majorana neutrino. They constitute
the purely neutrino families. We discuss the nature of a corresponding
mechanism responsible for the availability in all types of axial-vector
particles of a kind of flavour which distinguishes each of them from others by
a true charge characterized by a quantum number conserved at the interactions
between the C-odd fermion and the field of emission of the corresponding types
of gauge bosons. This regularity expresses the unidenticality of truly neutral
neutrino and antineutrino, confirming that an internal symmetry of a
C-noninvariant particle is described by an axial-vector space. Thereby, a true
flavour together with the earlier known lepton flavour predicts the existence
of leptonic strings and their birth in single and double beta decays as a unity
of flavour and gauge symmetry laws. Such a unified principle explains the
availability of a flavour symmetrical mode of neutrino oscillations.Comment: 19 pages, LaTex, Published version in IJT
Building icelandic igneous crust by repeated melt injections
Observations of microseismicity provide a powerful tool for mapping the movement of melt in the crust. Here we record remarkable sequences of earthquakes 20 km below the surface in the normally ductile crust in the vicinity of Askja volcano, in north-east Iceland. The earthquakes occur in swarms consisting of identical waveforms repeating as frequently as every 8 s for up to 3 hours. We use template waveforms from each swarm to detect and locate earthquakes with an automated cross-correlation technique. Events are located in the lower crust and are inferred to be the result of melt being injected into the crust. During melt intrusion high strain rates are produced in conjunction with high pore-fluid pressures from the melt or exsolved carbon dioxide. These cause brittle failure on high angle fault planes located at the tips of sills. Moment tensor solutions show that most of the earthquakes are opening cracks accompanied by volumetric increases. This is consistent with the failure causing the earthquakes by melt injection opening new tensile cracks. Analysis of the magnitude distribution of earthquakes within a swarm reveals a complicated relationship between the imposed strain rates and the fluids that cause brittle failure. The magnitude of the earthquakes is controlled by the distance fluids can migrate along a fault, whereas the frequency of the events is controlled by the strain rate. Faults at the tips of sills act to focus melt transport between sills and so must be an important method of transporting melt through the lower crust.Seismometers were borrowed from the Natural Environment Research Council (NERC) SEIS-UK facility (loans 914 and 968), and the work funded by a research grant from the NERC and by studentship funding for TG from Shell.This is the author accepted manuscript. The final version is available from Wiley via http://dx.doi.org/10.1002/2015JB01200
Radio Spectra and NVSS Maps of Decametric Sources
We constructed radio spectra for ~1400 UTR-2 sources and find that 46% of
them have concave curvature. Inspection of NVSS maps of 700 UTR sources
suggests that half of all UTR sources are either blends of two or more sources
or have an ultra-steep spectrum (USS). The fraction of compact USS sources in
UTR may be near 10%. Using NVSS and the Digitized Sky Survey(s) we expect to
double the UTR optical identification rate from currently ~19%.Comment: 2 pages, no figures; to appear in Proc. "Observational Cosmology with
the New Radio Surveys", eds. M. Bremer, N. Jackson & I. Perez-Fournon, Kluwer
Acad. Pres
High bat (Chiroptera) diversity in the Early Eocene of India
The geographic origin of bats is still unknown, and fossils of earliest bats are rare and poorly diversified, with, maybe, the exception of Europe. The earliest bats are recorded from the Early Eocene of North America, Europe, North Africa and Australia where they seem to appear suddenly and simultaneously. Until now, the oldest record in Asia was from the Middle Eocene. In this paper, we report the discovery of the oldest bat fauna of Asia dating from the Early Eocene of the Cambay Formation at Vastan Lignite Mine in Western India. The fossil taxa are described on the basis of well-preserved fragments of dentaries and lower teeth. The fauna is highly diversified and is represented by seven species belonging to seven genera and at least four families. Two genera and five species are new. Three species exhibit very primitive dental characters, whereas four others indicate more advanced states. Unexpectedly, this fauna presents strong affinities with the European faunas from the French Paris Basin and the German Messel locality. This could result from the limited fossil record of bats in Asia, but could also suggest new palaeobiogeographic scenarios involving the relative position of India during the Early Eocene
Need for Oral Health Policy in India
Dental diseases are a significant public health menace having a substantial impact on the quality of life which in turn affects the daily performance and general life satisfaction. There is a vast difference in health status including the oral health between urban and rural population of India and in other developing countries. The existing situation demands the formulation and implementation of National Oral Health Policy in India in order to expand the oral health care to make it more affordable, and reachable. An extensive literature search was conducted using various search engines in order to include relevant information in the review. Number of keywords and their combinations were used in order to extract appropriate data. Finally 24 out of 35 articles were selected upon detailed reading. The present paper focusses on some of the important subjects that can be considered while formulation of a National Oral Health Policy for the benefits of both the dental profession and community as a whole. There is a need of dental health planners and policy makers that have relevant qualifications and training in public health dentistry to understand the unique needs and resources for the development of an effective oral health policy. Professional dental organizations can also support government programs to provide basic oral health needs of extensive underserved population of this country.Keywords: Developing country, India, Mobile dentistry, Oral policy, Partnershi
Spectral Graph Convolutions for Population-based Disease Prediction
Exploiting the wealth of imaging and non-imaging information for disease
prediction tasks requires models capable of representing, at the same time,
individual features as well as data associations between subjects from
potentially large populations. Graphs provide a natural framework for such
tasks, yet previous graph-based approaches focus on pairwise similarities
without modelling the subjects' individual characteristics and features. On the
other hand, relying solely on subject-specific imaging feature vectors fails to
model the interaction and similarity between subjects, which can reduce
performance. In this paper, we introduce the novel concept of Graph
Convolutional Networks (GCN) for brain analysis in populations, combining
imaging and non-imaging data. We represent populations as a sparse graph where
its vertices are associated with image-based feature vectors and the edges
encode phenotypic information. This structure was used to train a GCN model on
partially labelled graphs, aiming to infer the classes of unlabelled nodes from
the node features and pairwise associations between subjects. We demonstrate
the potential of the method on the challenging ADNI and ABIDE databases, as a
proof of concept of the benefit from integrating contextual information in
classification tasks. This has a clear impact on the quality of the
predictions, leading to 69.5% accuracy for ABIDE (outperforming the current
state of the art of 66.8%) and 77% for ADNI for prediction of MCI conversion,
significantly outperforming standard linear classifiers where only individual
features are considered.Comment: International Conference on Medical Image Computing and
Computer-Assisted Interventions (MICCAI) 201
An additive subfamily of enlargements of a maximally monotone operator
We introduce a subfamily of additive enlargements of a maximally monotone
operator. Our definition is inspired by the early work of Simon Fitzpatrick.
These enlargements constitute a subfamily of the family of enlargements
introduced by Svaiter. When the operator under consideration is the
subdifferential of a convex lower semicontinuous proper function, we prove that
some members of the subfamily are smaller than the classical
-subdifferential enlargement widely used in convex analysis. We also
recover the epsilon-subdifferential within the subfamily. Since they are all
additive, the enlargements in our subfamily can be seen as structurally closer
to the -subdifferential enlargement
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