171 research outputs found
A micromachined thermoelectric sensor for natural gas analysis: Multivariate calibration results
The potential use of a micromachined thermopile based sensor device for analyzing natural gas is explored. The sensor consists of a thermally isolated hotplate, which is heated by the application of a sequence of programmed voltages to an integrated heater. Once the hotplate reaches a stationary temperature, the thermopile provides a signal proportional to the hotplate temperature. These signals are processed in order to determine different natural gas properties. Sensor response is mainly dependent on the thermal conductivity of the surrounding gas at different temperatures. Seven predicted properties (normal density, superior heating value, Wobbe index and the concentrations of methane, ethane, carbon dioxide and nitrogen) are calibrated against sensor signals by using multivariate regression, in particular partial least squares. Experimental data have been used for calibration and validation. Results show property prediction capability with reasonable accuracy except for prediction of carbon dioxide concentration. A detailed uncertainty analysis is provided to better understand the metrological limits of the system. These results imply for the first time the possibility of designing unprecedented low-cost natural gas analyzers. The concept may be extended to other constrained gas mixtures (e.g. of a known number of components) to enable low-cost multicomponent gas analyzers
Angioedema: diagnosis and treatment
El angioedema es una tumefacción de dermis de la piel y tejido conjuntivo de mucosas debido a vasodilatación y
edema. El hecho de que el angioedema interese al tejido conjuntivo de distintas mucosas tiene el riesgo vital de
afectar a la vía aérea superior. Por tanto, nos encontramos con un síndrome de máximo interés como objeto de
estudio por parte del clínico. Por una parte, es una entidad que puede tener consecuencias fatales, por otra, su
exploración clínica es altamente inespecífica para orientar su etiología. De esta manera, en esta revisión se
propone exponer las diferentes causas que pueden conducir a un angioedema para ayudar en la orientación
diagnóstica al clínico en su práctica habitual y el manejo terapéutico del mismo.Angioedema is a swelling of the dermis and connective tissue of mucous due to vasodilatation and edema.
The fact that angioedema interests mucosal tissues is a risk of affecting the upper airway. Therfore we have a
syndrome of great interest as study object by the clinician. On the one hand, it is an entity that can have fatal
consequences, on the other, the clinician examination is highly unspecific to guide its etiology. Thus, in this
review we try to expose the main different causes that can lead to angioedema to help clinician in diagnostic
practice and management thereof
Single Vectorlike Quark Production at the LHC
A gluon resonance G of mass below 1 TeV could be the origin of the t\bar{t}
forward-backward asymmetry observed at the Tevatron provided that new decay
modes G->\bar{q}Q, with q a standard quark and Q its massive excitation, make G
broad enough. We consider all the different cases, with q the top, the bottom
or a light quark and dominant decay modes Q->Wq' or Q->Zq. We show that current
experimental searches are unable to probe the model, but that minimal
departures from these analyses can explore a large region of its parameter
space for the current LHC luminosity. This includes the challenging case with
the new quarks decaying mostly into light quark flavors. In some channels not
only the heavy quark but also the massive gluon can be reconstructed, which
would stablish the origin of the t\bar{t} asymmetry. Similar analyses can be
applied to more general models with new massive gluons and vectorlike quarks.Comment: 17 pages, 8 figures. Version 2: references adde
Estudio y planificación de contenidos, materiales y metodologías docentes según el EEES: Itinerario Ocio Digital (Cuarto Curso de Ingeniería Multimedia)
En esta memoria se describe el proyecto realizado para la planificación de contenidos, materiales y metodología docente, y el seguimiento de las asignaturas del itinerario de Creación y Entretenimiento digital del cuarto curso del Grado en Ingeniería Multimedia de la Escuela Politécnica Superior, como continuación del planteamiento realizado en el proyecto de la red de cuarto curso configurada en el año 2012-13 (identificador 2687). En el marco creado por los nuevos estudios dentro del EEES, el proyecto ha tenido como objetivo principal la preparación, coordinación y seguimiento de las asignaturas del citado itinerario, teniendo en cuenta la aplicación de la metodología de Aprendizaje Basado en Proyectos (ABP). A partir de la experiencia adquirida en la planificación de cursos previos, se han elaborado las guías docentes de las asignaturas ajustando las del curso anterior. También se presentan los resultados obtenidos en la primera experiencia llevada a cabo en este curso, expresados en horas de dedicación al proyecto y en grado de satisfacción tanto del alumnado como del profesorado con la metodología ABP. Por último, se ha creado una página web informativa del itinerario explicando todos los aspectos de la metodología, y se han elaborado dos artículos detallando toda la labor realizada
Stable accretion and episodic outflows in the young transition disk system GM Aurigae
We investigate the structure and dynamics of the magnetospheric accretion
region and associated outflows on a scale smaller than 0.1 au around the young
transitional disk system GM Aur. We monitored the variability of the system on
timescales ranging from days to months, using high-resolution optical and
near-infrared spectroscopy, multiwavelength photometry, and low-resolution
near-infrared spectroscopy, over a total duration of six months (30 rotational
cycles). We analyzed the photometric and line profile variability to
characterize the accretion and ejection processes. The luminosity of the system
is modulated by surface spots at the stellar rotation period of 6.04 days. The
Balmer, Paschen, and Brackett hydrogen lines as well as the HeI 5876 A and HeI
10830 A line profiles are modulated on the same period. The PaB line flux
correlates with the photometric excess in the u' band, which suggests that most
of the line emission originates from the accretion process. High-velocity
redshifted absorptions reaching below the continuum periodically appear in the
near-infrared line profiles at the rotational phase in which the veiling and
line fluxes are the largest. These are signatures of a stable accretion funnel
flow and associated accretion shock at the stellar surface. This large-scale
magnetospheric accretion structure appears fairly stable over at least 15 and
possibly up to 30 rotational periods. In contrast, outflow signatures randomly
appear as blueshifted absorption components in the Balmer and HeI 10830 A line
profiles and disappear on a timescale of a few days. The coexistence of a
stable, large-scale accretion pattern and episodic outflows supports
magnetospheric ejections as the main process occurring at the star-disk
interface. Stable magnetospheric accretion and episodic outflows appear to be
physically linked on a scale of a few stellar radii in this system.Comment: 30 pages, 28 figures, 12 tables, accepted for publication in
Astronomy & Astrophysic
Epigenetics in schizophrenia: a pilot study of global DNA methylation in different brain regions associated with higher cognitive functions
Attempts to discover genes that are involved in the pathogenesis of major psychiatric disorders have been frustrating and often fruitless. Concern is building about the need to understand the complex ways in which nature and nurture interact to produce mental illness. We analyze the epigenome in several brain regions from schizophrenic patients with severe cognitive impairment using high-resolution (450K) DNA methylation array. We identified 139 differentially methylated CpG sites included in known and novel candidate genes sequences as well as in and intergenic sequences which functions remain unknown. We found that altered DNA methylation is not restricted to a particular region, but includes others such as CpG shelves and gene bodies, indicating the presence of different DNA methylation signatures depending on the brain area analyzed. Our findings suggest that epimutations are not relatables between different tissues or even between tissues' regions, highlighting the need to adequately study brain samples to obtain reliable data concerning the epigenetics of schizophrenia
New Higgs Production Mechanism in Composite Higgs Models
Composite Higgs models are only now starting to be probed at the Large Hadron
Collider by Higgs searches. We point out that new resonances, abundant in these
models, can mediate new production mechanisms for the composite Higgs. The new
channels involve the exchange of a massive color octet and single production of
new fermion resonances with subsequent decays into the Higgs and a Standard
Model quark. The sizable cross section and very distinctive kinematics allow
for a very clean extraction of the signal over the background with high
statistical significance. Heavy gluon masses up to 2.8 TeV can be probed with
data collected during 2012 and up to 5 TeV after the energy upgrade to
TeV.Comment: 27 pages, 22 figures. V2: typos corrected, matches published versio
Epigenetics in schizophrenia: a pilot study of global DNA methylation in different brain regions associated with higher cognitive functions
Attempts to discover genes that are involved in the pathogenesis of major psychiatric disorders have been frustrating and often fruitless. Concern is building about the need to understand the complex ways in which nature and nurture interact to produce mental illness. We analyze the epigenome in several brain regions from schizophrenic patients with severe cognitive impairment using high-resolution (450K) DNA methylation array. We identified 139 differentially methylated CpG sites included in known and novel candidate genes sequences as well as in and intergenic sequences which functions remain unknown. We found that altered DNA methylation is not restricted to a particular region, but includes others such as CpG shelves and gene bodies, indicating the presence of different DNA methylation signatures depending on the brain area analyzed. Our findings suggest that epimutations are not relatables between different tissues or even between tissues' regions, highlighting the need to adequately study brain samples to obtain reliable data concerning the epigenetics of schizophrenia
Les Houches 2015: Physics at TeV colliders - new physics working group report
We present the activities of the 'New Physics' working group for the 'Physics
at TeV Colliders' workshop (Les Houches, France, 1-19 June, 2015). Our report
includes new physics studies connected with the Higgs boson and its properties,
direct search strategies, reinterpretation of the LHC results in the building
of viable models and new computational tool developments. Important signatures
for searches for natural new physics at the LHC and new assessments of the
interplay between direct dark matter searches and the LHC are also considered.Comment: Proceedings of the New Physics Working Group of the 2015 Les Houches
Workshop, Physics at TeV Colliders, Les Houches 1-19 June 2015. 197 page
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