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Building on Redundancy: Factoid Question Answering, Robust Retrieval and the "Other"
We have explored how redundancy based techniques can be used in improving factoid question answering, definitional
questions (âotherâ), and robust retrieval. For the factoids, we explored the meta approach: we submit the questions to the
several open domain question answering systems available on the Web and applied our redundancy-based triangulation
algorithm to analyze their outputs in order to identify the most promising answers. Our results support the added value of the
meta approach: the performance of the combined system surpassed the underlying performances of its components. To
answer definitional (âotherâ) questions, we were looking for the sentences containing re-occurring pairs of noun entities
containing the elements of the target. For robust retrieval, we applied our redundancy based Internet mining technique to
identify the concepts (single word terms or phrases) that were highly related to the topic (query) and expanded the queries
with them. All our results are above the mean performance in the categories in which we have participated, with one of our
robust runs being the best in its category among all 24 participants. Overall, our findings support the hypothesis that using as
much as possible textual data, specifically such as mined from the World Wide Web, is extremely promising.published_or_final_versio
Fault kinematics in northern Central America and coupling along the subduction interface of the Cocos Plate, from GPS data in Chiapas (Mexico), Guatemala and El Salvador
International audienceNew GPS measurements in Chiapas (Mexico), Guatemala and El Salvador are used to constrain the fault kinematics in the North America (NA), Caribbean (CA) and Cocos (CO) plates triple junction area. The regional GPS velocity field is first analysed in terms of strain partitioning across the major volcano-tectonic structures, using elastic half-space modelling, then inverted through a block model. We show the dominant role of the Motagua Fault with respect to the Polochic Fault in the accommodation of the present-day deformation associated with the NA and CA relative motion. The NA/CA motion decreases from 18-22 mm yrâ1 in eastern Guatemala to 14-20 mm yrâ1 in central Guatemala (assuming a uniform locking depth of 14-28 km), down to a few millimetres per year in western Guatemala. As a consequence, the western tip of the CA Plate deforms internally, with â9 mm yrâ1 of east-west extension (â5 mm yrâ1 across the Guatemala city graben alone). Up to 15 mm yrâ1 of dextral motion can be accommodated across the volcanic arc in El Salvador and southeastern Guatemala. The arc seems to mark the northern boundary of an independent forearc sliver (AR), pinned to the NA plate. The inversion of the velocity field shows that a four-block (NA, CA, CO and AR) model, that combines relative block rotations with elastic deformation at the block boundaries, can account for most of the GPS observations and constrain the overall kinematics of the active structures. This regional modelling also evidences lateral variations of coupling at the CO subduction interface, with a fairly high-coupling (â0.6) offshore Chiapas and low-coupling (â0.25) offshore Guatemala and El Salvador
Characterization and in vitro spread of mesquite (Prosopis laevigata (Humb. & Bonpl. ex Willd.) M.C.Johnst.)
Objective: To analyze fruit characteristics, genetic diversity, and in vitro spread of mesquite genotypes (Prosopis laevigata (Humb. & Bonpl.) ex Willd.) from the plains of Ojuelos-Aguascalientes, Mexico.
Design/Methodology/Approach: Fruit and leaf samples were collected from 20 mesquite genotypes to analyze and extract DNA to determine their diversity using RAPDs. Simultaneously, in vitro spread tests were performed.
Results: The Ojuelos de Jalisco genotype stood out for the weight of its fruits, while La Presa genotype stood out for its degrees Brix. Genotypes were grouped according to their best growth condition for their genetic analysis. In in vitro spread, AG3 with IBA allowed stem/shoot elongation and root formation; meanwhile, AgNO3 prevents leaf fall, allowing rooting and transfer to the soil.
Study Implications/Limitations: This study about mesquite (P. laevigata) was limited to the plains of Ojuelos-Aguascalientes.
Findings/Conclusions: Mesquite plants from the Ojuelos-Aguascalientes subregion, Mexico, were identified and georeferenced; likewise, a methodology for its in vitro spread was developed
Allocating Family Responsibilities for Dependent Older People in Mexico and Peru
This paper applies different analytical frameworks to explore processes of family bargaining about providing care for dependent older people in Mexico and Peru. These frameworks include cultural norms, life course effects and material exchange. The paper is based on 19 in-depth qualitative family case studies, which are linked to a wider set of quantitative survey data. Care arrangements and bargaining processes are revealed to be highly gendered, and largely conform to prevailing cultural norms. Rather than neutral and objective, the self-identified role as main carer is found to be subjective and potentially ambiguous. The few men who self-identify as main carers are more likely to play an indirect, organisational role than engage directly in daily care. As such, bargaining mainly relates to which woman performs the main care role, and large family networks mean that there is usually more than one candidate carer. Bargaining can occur inter-generationally and conjugally, but bargaining between siblings is of particular importance. Bargaining is framed by the uncertain trajectory of older peopleâs care needs, and arrangements are sometimes reconfigured in response to changing care needs or family circumstances. Taking the narratives at face value, the influence of life course effects on bargaining and care arrangements is more obvious than material exchange. There are, however, indications that economic considerations, particularly inheritance, still play an important behind the scenes role
Selective inhibition of HDAC6 regulates expression of the oncogenic driver EWSR1-FLI1 through the EWSR1 promoter in Ewing sarcoma
Ewing sarcoma (EWS) is an aggressive bone and soft tissue tumor of children and young adults in which the principal driver is a fusion gene, EWSR1-FLI1. Although the essential role of EWSR1-FLI1 protein in the regulation of oncogenesis, survival, and tumor progression processes has been described in-depth, little is known about the regulation of chimeric fusion-gene expression. Here, we demonstrate that the active nuclear HDAC6 in EWS modulates the acetylation status of specificity protein 1 (SP1), consequently regulating the SP1/P300 activator complex binding to EWSR1 and EWSR1-FLI1 promoters. Selective inhibition of HDAC6 impairs binding of the activator complex SP1/P300, thereby inducing EWSR1-FLI1 downregulation and significantly reducing its oncogenic functions. In addition, sensitivity of EWS cell lines to HDAC6 inhibition is higher than other tumor or non-tumor cell lines. High expression of HDAC6 in primary EWS tumor samples from patients correlates with a poor prognosis in two independent series accounting 279 patients. Notably, a combination treatment of a selective HDAC6 and doxorubicin (a DNA damage agent used as a standard therapy of EWS patients) dramatically inhibits tumor growth in two EWS murine xenograft models. These results could
lead to suitable and promising therapeutic alternatives for patients with EWS.Research in the E.D.A. lab is supported by AsociaciĂłn Española Contra el CĂĄncer (AECC), the Ministry of Science of Spain-FEDER (CIBERONC, PI1700464, PI2000003, RD06/0020/0059)S. D.G.D. and L.H.P. are supported by CIBERONC (CB16/12/00361). D.G.D., M.J.R. and L.H.P. are PhD researchers funded by the ConsejerĂa de Salud, Junta de AndalucĂa (PI-0197-2016, ECAI F2-0012-2018 and PI-0013-2018, respectively).Peer reviewe
Search for New Physics with Jets and Missing Transverse Momentum in pp collisions at sqrt(s) = 7 TeV
A search for new physics is presented based on an event signature of at least
three jets accompanied by large missing transverse momentum, using a data
sample corresponding to an integrated luminosity of 36 inverse picobarns
collected in proton--proton collisions at sqrt(s)=7 TeV with the CMS detector
at the LHC. No excess of events is observed above the expected standard model
backgrounds, which are all estimated from the data. Exclusion limits are
presented for the constrained minimal supersymmetric extension of the standard
model. Cross section limits are also presented using simplified models with new
particles decaying to an undetected particle and one or two jets
Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV
A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay
channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7
TeV is presented. The data were collected at the LHC, with the CMS detector,
and correspond to an integrated luminosity of 4.6 inverse femtobarns. No
significant excess is observed above the background expectation, and upper
limits are set on the Higgs boson production cross section. The presence of the
standard model Higgs boson with a mass in the 270-440 GeV range is excluded at
95% confidence level.Comment: Submitted to JHE
X-ray emission from the Sombrero galaxy: discrete sources
We present a study of discrete X-ray sources in and around the
bulge-dominated, massive Sa galaxy, Sombrero (M104), based on new and archival
Chandra observations with a total exposure of ~200 ks. With a detection limit
of L_X = 1E37 erg/s and a field of view covering a galactocentric radius of ~30
kpc (11.5 arcminute), 383 sources are detected. Cross-correlation with Spitler
et al.'s catalogue of Sombrero globular clusters (GCs) identified from HST/ACS
observations reveals 41 X-rays sources in GCs, presumably low-mass X-ray
binaries (LMXBs). We quantify the differential luminosity functions (LFs) for
both the detected GC and field LMXBs, whose power-low indices (~1.1 for the
GC-LF and ~1.6 for field-LF) are consistent with previous studies for
elliptical galaxies. With precise sky positions of the GCs without a detected
X-ray source, we further quantify, through a fluctuation analysis, the GC LF at
fainter luminosities down to 1E35 erg/s. The derived index rules out a
faint-end slope flatter than 1.1 at a 2 sigma significance, contrary to recent
findings in several elliptical galaxies and the bulge of M31. On the other
hand, the 2-6 keV unresolved emission places a tight constraint on the field
LF, implying a flattened index of ~1.0 below 1E37 erg/s. We also detect 101
sources in the halo of Sombrero. The presence of these sources cannot be
interpreted as galactic LMXBs whose spatial distribution empirically follows
the starlight. Their number is also higher than the expected number of cosmic
AGNs (52+/-11 [1 sigma]) whose surface density is constrained by deep X-ray
surveys. We suggest that either the cosmic X-ray background is unusually high
in the direction of Sombrero, or a distinct population of X-ray sources is
present in the halo of Sombrero.Comment: 11 figures, 5 tables, ApJ in pres
Combined search for the quarks of a sequential fourth generation
Results are presented from a search for a fourth generation of quarks
produced singly or in pairs in a data set corresponding to an integrated
luminosity of 5 inverse femtobarns recorded by the CMS experiment at the LHC in
2011. A novel strategy has been developed for a combined search for quarks of
the up and down type in decay channels with at least one isolated muon or
electron. Limits on the mass of the fourth-generation quarks and the relevant
Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a
simple extension of the standard model with a sequential fourth generation of
fermions. The existence of mass-degenerate fourth-generation quarks with masses
below 685 GeV is excluded at 95% confidence level for minimal off-diagonal
mixing between the third- and the fourth-generation quarks. With a mass
difference of 25 GeV between the quark masses, the obtained limit on the masses
of the fourth-generation quarks shifts by about +/- 20 GeV. These results
significantly reduce the allowed parameter space for a fourth generation of
fermions.Comment: Replaced with published version. Added journal reference and DO
Search for anomalous t t-bar production in the highly-boosted all-hadronic final state
A search is presented for a massive particle, generically referred to as a
Z', decaying into a t t-bar pair. The search focuses on Z' resonances that are
sufficiently massive to produce highly Lorentz-boosted top quarks, which yield
collimated decay products that are partially or fully merged into single jets.
The analysis uses new methods to analyze jet substructure, providing
suppression of the non-top multijet backgrounds. The analysis is based on a
data sample of proton-proton collisions at a center-of-mass energy of 7 TeV,
corresponding to an integrated luminosity of 5 inverse femtobarns. Upper limits
in the range of 1 pb are set on the product of the production cross section and
branching fraction for a topcolor Z' modeled for several widths, as well as for
a Randall--Sundrum Kaluza--Klein gluon. In addition, the results constrain any
enhancement in t t-bar production beyond expectations of the standard model for
t t-bar invariant masses larger than 1 TeV.Comment: Submitted to the Journal of High Energy Physics; this version
includes a minor typo correction that will be submitted as an erratu
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