2,040 research outputs found
Single-Document and Multi-Document Summarization Techniques for Email Threads Using Sentence Compression First Author Affiliation / Address line 1
We present two approaches to email thread summarization: Collective Message Summarization (CMS) applies a multi-document summarization approach, while Individual Message Summarization (IMS) treats the problem as a sequence of single-document summarization tasks. Both approaches are implemented in our general framework driven by sentence compression. Instead of a purely extractive approach, we employ linguistic and statistical methods to generate multiple compressions, and then select from those candidates to produce a final summary. We demonstrate our techniques on the Enron collection—a very challenging corpus because of the highly technical language. Results suggest that CMS represents a better approach and additional findings pave the way for future explorations.
Spiralling dynamics near heteroclinic networks
There are few explicit examples in the literature of vector fields exhibiting
complex dynamics that may be proved analytically. We construct explicitly a
{two parameter family of vector fields} on the three-dimensional sphere
\EU^3, whose flow has a spiralling attractor containing the following: two
hyperbolic equilibria, heteroclinic trajectories connecting them {transversely}
and a non-trivial hyperbolic, invariant and transitive set. The spiralling set
unfolds a heteroclinic network between two symmetric saddle-foci and contains a
sequence of topological horseshoes semiconjugate to full shifts over an
alphabet with more and more symbols, {coexisting with Newhouse phenonema}. The
vector field is the restriction to \EU^3 of a polynomial vector field in
\RR^4. In this article, we also identify global bifurcations that induce
chaotic dynamics of different types.Comment: change in one figur
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METACOHORTS for the study of vascular disease and its contribution to cognitive decline and neurodegeneration: An initiative of the Joint Programme for Neurodegenerative Disease Research.
Dementia is a global problem and major target for health care providers. Although up to 45% of cases are primarily or partly due to cerebrovascular disease, little is known of these mechanisms or treatments because most dementia research still focuses on pure Alzheimer's disease. An improved understanding of the vascular contributions to neurodegeneration and dementia, particularly by small vessel disease, is hampered by imprecise data, including the incidence and prevalence of symptomatic and clinically "silent" cerebrovascular disease, long-term outcomes (cognitive, stroke, or functional), and risk factors. New large collaborative studies with long follow-up are expensive and time consuming, yet substantial data to advance the field are available. In an initiative funded by the Joint Programme for Neurodegenerative Disease Research, 55 international experts surveyed and assessed available data, starting with European cohorts, to promote data sharing to advance understanding of how vascular disease affects brain structure and function, optimize methods for cerebrovascular disease in neurodegeneration research, and focus future research on gaps in knowledge. Here, we summarize the results and recommendations from this initiative. We identified data from over 90 studies, including over 660,000 participants, many being additional to neurodegeneration data initiatives. The enthusiastic response means that cohorts from North America, Australasia, and the Asia Pacific Region are included, creating a truly global, collaborative, data sharing platform, linked to major national dementia initiatives. Furthermore, the revised World Health Organization International Classification of Diseases version 11 should facilitate recognition of vascular-related brain damage by creating one category for all cerebrovascular disease presentations and thus accelerate identification of targets for dementia prevention.The following funders supported the work. Joint Programme for Neurodegenerative Disease (JPND) Research, specifically the UK Medical Research Council, the Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE) and the Canadian Institutes of Health Research (CIHR). The Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) through the Pools Engagement in Europe (PEER) funding from the Scottish Funding Council. The Therese Pei Fong Chow Research Centre for Prevention of Dementia (in memory of Donald H K Chow). We thank the Siemens Foundation, Munich, Germany for providing the workshop venue and catering. F-EdeL acknowledges VIDI Innovation Grant from ZonMW ref 016.126.351. PMM acknowledges generous support from the Edmond J Safra Foundation and Lily Safra and the Imperial College Health Trust BRC. PMWB is Stroke Association Professor of Stroke Medicine. CdeC acknowledges support from Centre Grant NIH P30 AG 010129.This is the final version of the article. It first appeared from Elsevier via https://doi.org/10.1016/j.jalz.2016.06.00
Magnetic coupling properties of rare-earth metals (Gd, Nd) doped ZnO: first-principles calculations
The electronic structure and magnetic coupling properties of rare-earth
metals (Gd, Nd) doped ZnO have been investigated using first-principles
methods. We show that the magnetic coupling between Gd or Nd ions in the
nearest neighbor sites is ferromagnetic. The stability of the ferromagnetic
coupling between Gd ions can be enhanced by appropriate electron doping into
ZnO:Gd system and the room-temperature ferromagnetism can be achieved. However,
for ZnO:Nd system, the ferromagnetism between Nd ions can be enhanced by
appropriate holes doping into the sample. The room-temperature ferromagnetism
can also be achieved in the \emph{n}-conducting ZnO:Nd sample. Our calculated
results are in good agreement with the conclusions of the recent experiments.
The effect of native defects (V, V) on the
ferromagnetism is also discussed.Comment: 5 pages, 5 figure
Superconductivity in iron telluride thin films under tensile stress
By realizing in thin films a tensile stress state, superconductivity of 13 K
was introduced into FeTe, an non-superconducting parent compound of the iron
pnictides and chalcogenides, with transition temperature higher than that of
its superconducting isostructural counterpart FeSe. For these tensile stressed
films, the superconductivity is accompanied by the softening of the first-order
magnetic and structural phase transition; and also, the in-plane extension and
out-of-plane contraction are universal in all FeTe films independent of sign of
lattice mismatch, either positive or negative. Moreover, the correlations were
found exist between the transition temperatures and the tetrahedra bond angles
in these thin films.Comment: 4 pages, 4 figures, accepted by Physical Review Letter
Kinesin-II is required for axonal transport of choline acetyltransferase in Drosophila
KLP64D and KLP68D are members of the kinesin-II family of proteins in Drosophila. Immunostaining for KLP68D and ribonucleic acid in situ hybridization for KLP64D demonstrated their preferential expression in cholinergic neurons. KLP68D was also found to accumulate in cholinergic neurons in axonal obstructions caused by the loss of kinesin light chain. Mutations in the KLP64D gene cause uncoordinated sluggish movement and death, and reduce transport of choline acetyltransferase from cell bodies to the synapse. The inviability of KLP64D mutations can be rescued by expression of mammalian KIF3A. Together, these data suggest that kinesin-II is required for the axonal transport of a soluble enzyme, choline acetyltransferase. in a specific subset of neurons in Drosophila. Furthermore, the data lead to the conclusion that the cargo transport requirements of different classes of neurons may lead to upregulation of specific pathways of axonal transport
Spin Hall effect in the kagome lattice with Rashba spin-orbit interaction
We study the spin Hall effect in the kagom\'{e} lattice with Rashba
spin-orbit coupling. The conserved spin Hall conductance (see
text) and its two components, i.e., the conventional term
and the spin-torque-dipole term , are numerically
calculated, which show a series of plateaus as a function of the electron Fermi
energy . A consistent two-band analysis, as well as a Berry-phase
interpretation, is also given. We show that these plateaus are a consequence of
the various Fermi-surface topologies when tuning . In particular,
we predict that compared to the case with the Fermi surface encircling the
point in the Brillouin zone, the amplitude of the spin Hall
conductance with the Fermi surface encircling the points is twice
enhanced, which makes it highly meaningful in the future to systematically
carry out studies of the -valley spintronics.Comment: 7 pages, 3 figures. Phys. Rev. B (in press
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