181 research outputs found
Description of immature stages of Nemophora bellela (Walker, 1863) (Lepidoptera: Adelidae)
Little life history data is available on the larvae of Adelidae (Lepidoptera, Adeloidea). We provide information on the life history of Nemophora bellela (Walker, 1863), a circumpolar adelid species occurring in northern Europe on peat bogs and open tundra with Betula nana. The habitat is described and details of the larval behavior and larval diet are provided. The later instar larvae are case dwelling and feed on the ground on detritus. The larval case and chaetotaxy are described in detail. The female pupal exuviae is described. Our observations on the life history of N. bellela are in general agreement with the known details of the life history of related species, but some differences were also observed
Winding effects on brane/anti-brane pairs
We study a brane/anti-brane configuration which is separated along a compact
direction by constructing a tachyon effective action which takes into account
transverse scalars. Such an action is relevant in the study of HQCD model of
Sakai and Sugimoto of chiral symmetry breaking, where the size of the compact
circle sets the confinement scale. Our approach is motivated by string theory
orbifold constructions and gives a route to model inhomogeneous tachyon decay.
We illustrate the techniques involved with a relatively simple example of a
harmonic oscillator on a circle. We will then repeat the analysis for the
Sakai-Sugimoto model and show that by integrating out the winding modes will
provide us with a renormalized action with a lower energy than that of
truncating to zero winding sector.Comment: 21 pages, 3 figures. v3: discussion and references added, published
versio
Tarmo: A Framework for Parallelized Bounded Model Checking
This paper investigates approaches to parallelizing Bounded Model Checking
(BMC) for shared memory environments as well as for clusters of workstations.
We present a generic framework for parallelized BMC named Tarmo. Our framework
can be used with any incremental SAT encoding for BMC but for the results in
this paper we use only the current state-of-the-art encoding for full PLTL.
Using this encoding allows us to check both safety and liveness properties,
contrary to an earlier work on distributing BMC that is limited to safety
properties only.
Despite our focus on BMC after it has been translated to SAT, existing
distributed SAT solvers are not well suited for our application. This is
because solving a BMC problem is not solving a set of independent SAT instances
but rather involves solving multiple related SAT instances, encoded
incrementally, where the satisfiability of each instance corresponds to the
existence of a counterexample of a specific length. Our framework includes a
generic architecture for a shared clause database that allows easy clause
sharing between SAT solver threads solving various such instances.
We present extensive experimental results obtained with multiple variants of
our Tarmo implementation. Our shared memory variants have a significantly
better performance than conventional single threaded approaches, which is a
result that many users can benefit from as multi-core and multi-processor
technology is widely available. Furthermore we demonstrate that our framework
can be deployed in a typical cluster of workstations, where several multi-core
machines are connected by a network
Fluctuations of a holographic quantum Hall fluid
We analyze the neutral spectrum of the holographic quantum Hall fluid
described by the D2-D8' model. As expected for a quantum Hall state, we find
the system to be stable and gapped and that, at least over much of the
parameter space, the lowest excitation mode is a magneto-roton. In addition, we
find magneto-rotons in higher modes as well. We show that these magneto-rotons
are direct consequences of level crossings between vector and scalar modes.Comment: 20 pages, 8 figures; v.2 figures improved, 2 figures added, and text
clarified particularly in Sec. 5, to appear in JHE
Hyperspectral remote sensing of foliar nitrogen content
http://www.pnas.orgPeer reviewe
The correlation between reading and mathematics ability at age twelve has a substantial genetic component
Dissecting how genetic and environmental influences impact on learning is helpful for maximizing numeracy and literacy. Here we show, using twin and genome-wide analysis, that there is a substantial genetic component to children’s ability in reading and mathematics, and estimate that around one half of the observed correlation in these traits is due to shared genetic effects (so-called Generalist Genes). Thus, our results highlight the potential role of the learning environment in contributing to differences in a child’s cognitive abilities at age twelve
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Sporadic naturally occurring melanoma in dogs as a preclinical model for human melanoma
Melanoma represents a significant malignancy in humans and dogs. Different from genetically engineered models, sporadic canine melanocytic neoplasms share several characteristics with human disease that could make dogs a more relevant preclinical model. Canine melanomas rarely arise in sun-exposed sites. Most occur in the oral cavity, with a subset having intra-epithelial malignant melanocytes mimicking the in situ component of human mucosal melanoma. The spectrum of canine melanocytic neoplasia includes benign lesions with some analogy to nevi, as well as invasive primary melanoma, and widespread metastasis. Growing evidence of distinct subtypes in humans, differing in somatic and predisposing germ-line genetic alterations, cell of origin, epidemiology, relationship to ultraviolet radiation and progression from benign to malignant tumors, may also exist in dogs. Canine and human mucosal melanomas appear to harbor BRAF, NRAS, and c-kit mutations uncommonly, compared with human cutaneous melanomas, although both species share AKT and MAPK signaling activation. We conclude that there is significant overlap in the clinical and histopathological features of canine and human mucosal melanomas. This represents opportunity to explore canine oral cavity melanoma as a preclinical model
Genetic risk and a primary role for cell-mediated immune mechanisms in multiple sclerosis.
Multiple sclerosis is a common disease of the central nervous system in which the interplay between inflammatory and neurodegenerative processes typically results in intermittent neurological disturbance followed by progressive accumulation of disability. Epidemiological studies have shown that genetic factors are primarily responsible for the substantially increased frequency of the disease seen in the relatives of affected individuals, and systematic attempts to identify linkage in multiplex families have confirmed that variation within the major histocompatibility complex (MHC) exerts the greatest individual effect on risk. Modestly powered genome-wide association studies (GWAS) have enabled more than 20 additional risk loci to be identified and have shown that multiple variants exerting modest individual effects have a key role in disease susceptibility. Most of the genetic architecture underlying susceptibility to the disease remains to be defined and is anticipated to require the analysis of sample sizes that are beyond the numbers currently available to individual research groups. In a collaborative GWAS involving 9,772 cases of European descent collected by 23 research groups working in 15 different countries, we have replicated almost all of the previously suggested associations and identified at least a further 29 novel susceptibility loci. Within the MHC we have refined the identity of the HLA-DRB1 risk alleles and confirmed that variation in the HLA-A gene underlies the independent protective effect attributable to the class I region. Immunologically relevant genes are significantly overrepresented among those mapping close to the identified loci and particularly implicate T-helper-cell differentiation in the pathogenesis of multiple sclerosis
Analyzing European Union Politics
The speed and depth with which the European Communities/
European Union has evolved is breathtaking and
has radically shaped the life of the continent. Ever since the
beginning of this ambitious economic and political project,
scholars around the world have tried to explain the underlying
logic behind it and the mechanisms of its functioning.
Thus, a plethora of studies developed alongside the evolution
of the EU.
SENT (Network of European Studies) is an innovative
and ambitious project which brought together about 100
partners from the EU member states, candidate and associated
countries, and other parts of the world. It was a far
reaching project aimed to overcome disciplinary and geographical-
linguistic boundaries in order to assess the state
of EU studies today, as well as the idea of Europe as transmitted
by schools, national politicians, the media, etc.
SENT’s main goal was to map European studies, in order
to get a comprehensive picture of the evolution of European
studies over the last decades in different disciplines and
countries. This approach permitted to achieve a better understanding
of the direction these studies are now taking.
Five disciplines were identified where EU studies have particularly
evolved: law, politics, economics, history, and social
and cultural studies. The mapping of EU studies thus includes
a review of the most studied issues in EU studies today,
the main academic schools, the most influential journals
and books published, but it also shows how local realities
and national identities affect the study and teaching of Europe
around the world. In addition, an important work was
done in mapping and discussing teaching methodologies in
relation to European studies with the aim of introducing and
diffusing the most up-to-date techniques
Remodelling of Cortical Actin Where Lytic Granules Dock at Natural Killer Cell Immune Synapses Revealed by Super-Resolution Microscopy
Super-resolution 3D imaging reveals remodeling of the cortical actin meshwork at the natural killer cell immune synapse, which is likely to be important for secretion of lytic granules
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