4,469 research outputs found
¿De los nuevos medios a las hipermediaciones?
El nombre que le he dado a este artículo recoge la apuesta de Scolari: actualizar el trabajo de Martin-Barbero. Sin duda, la propuesta es audaz desde el punto de vista de la variable tecnológica (habla de hipermediaciones); lamentablemente en el trabajo se pierde el fondo: no aparece el aparato crítico ni la lectura encarnada en la realidad socio-política de América Latina. En varios autores y autoras citados aparece reiteradamente la categoría convergencia: la destacaré como lo merece.-La interactividad. -Caracterización del Nuevo Medio. -Aproximación a
una taxonomía de los NM. -Lista de referencias
Tensorial analisis of the superposed deformation in the easthern border of the Madrid basin
An analysis of Neogene brittle deformation using fault populatíon analysis methods has been carried out between the SW border of the Iberian Range and Altomira Range. Two main paleostress fields have been established: 1) N70E - N120E compression (Altomira paleostress field) ofLate Oligocene - Early Miocene age that induced the formation of the SW border of Iberian Range and Altomira - Pareja thrust belts with reverse and strike-slip faults.
2) N140-N160E compression (Guadarrama paleostress field) of Middle Aragonian - early Pleistocene age that reactivated previous faults with strikeslip movement along the Iberian Range. A superposition of two regional stress fields (Iberian and Guadarrama) is proposed to explain E-W compression that formed Altomira Range. Stress tensorial additions have been realized to check this hypothesis
Quantifying offshore fore-arc deformation and splay-fault slip using drowned Pleistocene shorelines, Arauco Bay, Chile
Indexación: Web of Science; Scopus.Most of the deformation associated with the seismic cycle in subduction zones occurs offshore and has been therefore difficult to quantify with direct observations at millennial timescales. Here we study millennial deformation associated with an active splay-fault system in the Arauco Bay area off south central Chile. We describe hitherto unrecognized drowned shorelines using high-resolution multibeam bathymetry, geomorphic, sedimentologic, and paleontologic observations and quantify uplift rates using a Landscape Evolution Model. Along a margin-normal profile, uplift rates are 1.3 m/ka near the edge of the continental shelf, 1.5 m/ka at the emerged Santa María Island, −0.1 m/ka at the center of the Arauco Bay, and 0.3 m/ka in the mainland. The bathymetry images a complex pattern of folds and faults representing the surface expression of the crustal-scale Santa María splay-fault system. We modeled surface deformation using two different structural scenarios: deep-reaching normal faults and deep-reaching reverse faults with shallow extensional structures. Our preferred model comprises a blind reverse fault extending from 3 km depth down to the plate interface at 16 km that slips at a rate between 3.0 and 3.7 m/ka. If all the splay-fault slip occurs during every great megathrust earthquake, with a recurrence of ~150–200 years, the fault would slip ~0.5 m per event, equivalent to a magnitude ~6.4 earthquake. However, if the splay-fault slips only with a megathrust earthquake every ~1000 years, the fault would slip ~3.7 m per event, equivalent to a magnitude ~7.5 earthquake. ©2017. American Geophysical Union.http://onlinelibrary.wiley.com/doi/10.1002/2016JB013339/epd
Detection of Adversarial Training Examples in Poisoning Attacks through Anomaly Detection
Machine learning has become an important component for many systems and applications including computer vision, spam filtering, malware and network intrusion detection, among others. Despite the capabilities of machine learning algorithms to extract valuable information from data and produce accurate predictions, it has been shown that these algorithms are vulnerable to attacks. Data poisoning is one of the most relevant security threats against machine learning systems, where attackers can subvert the learning process by injecting malicious samples in the training data. Recent work in adversarial machine learning has shown that the so-called optimal attack strategies can successfully poison linear classifiers, degrading the performance of the system dramatically after compromising a small fraction of the training dataset. In this paper we propose a defence mechanism to mitigate the effect of these optimal poisoning attacks based on outlier detection. We show empirically that the adversarial examples generated by these attack strategies are quite different from genuine points, as no detectability constrains are considered to craft the attack. Hence, they can be detected with an appropriate pre-filtering of the training dataset
Síntesis estratigráfica del Terciario del borde Sur de la Cuenca del Ebro: unidades genéticas
In the southern margin of the Ebro Basin eigth Tectosedimentary Units (TSU) have been defined by means of the application of tectosedimentary analysis. These units are limited by sedimentary breaks which can be recognized in the whole studied area. The sedimentary breaks are genetically related to diastrophic evolution, and they are shown as angular or syntectonic unconformities at the basin margins. Each TSU has aparticular sequential evolution, generally complex, but with a similar trend in the entire area. For each unit the litologic composition, evolution, boundaries and chronostratigraphy are established. The three first units are placed in the Palaeogene, the fourth one includes the Palaeogene-Neogene boundary and the four last ones are Neogene in age. The chronostratigraphic interval of each one is, respectively: Thanetian-Bartonian, Bartonian-Priabonian, Priabonian-Lower Oligocene, Upper Oligocene-Agenian, Agenim-Middle Aragonian, Middle Aragonim-Upper Aragonian, Upper Aragonian-Upper Vallesian, and Turolian. Finally the equivalences between the Tectosedimentary Units and the cartographic units defiiied by other authors have been establised
Engineering and harnessing giant atoms in high-dimensional baths: a cold atoms' implementation
Emitters coupled simultaneously to distant positions of a photonic bath, the
so-called giant atoms, represent a new paradigm in quantum optics. When coupled
to one-dimensional baths, as recently implemented with transmission lines or
SAW waveguides, they lead to striking effects such as chiral emission or
decoherence-free atomic interactions. Here, we show how to create giant atoms
in dynamical state-dependent optical lattices, which offers the possibility of
coupling them to structured baths in arbitrary dimensions. This opens up new
avenues to a variety of phenomena and opportunities for quantum simulation. In
particular, we show how to engineer unconventional radiation patterns, like
multi-directional chiral emission, as well as collective interactions that can
be used to simulate non-equilibrium many-body dynamics with no analogue in
other setups. Besides, the recipes we provide to harness giant atoms in high
dimensions can be exported to other platforms where such non-local couplings
can be engineered.Comment: 9 pages, 5 figures. Title changed to accommodate to the new focus of
the main text. Several typos correcte
Fijación interna versus percutánea en fracturas diafisarias de metacarpianos: estudio de casos-controles
Objetivos: comparación de resultados clínicos de fijación interna versus fijación percutánea. Material
y Métodos: estudio retrospectivo de casos y controles de 58 fracturas de metacarpianos (43 pacientes). Se incluyeron
las fracturas diafisarias, sin afectación articular. Se excluyeron si había afectación del pulgar o de falanges, fracturas
abiertas o más de 3 fracturas en la misma mano. Un total de 26 fracturas fueron tratadas con fijación interna y
32 con percutánea. Con un seguimiento medio de 2,5 años (rango, 1-4), se valoró la función mediante movilidad activa
total (MAT), fuerza, DASH, EAV de dolor y resultado radiográfico. Resultados: con ambos tratamientos los resultados
fueron satisfactorios. El tiempo de consolidación y alineación radiográfica fueron similares. Todas las valoraciones
clínicas, objetivas y subjetivas, fueron mejores en el grupo de fijación interna, así como la tasa de retorno a
las actividades previas. En el grupo de fijación interna hubo un caso de pseudoartrosis que fue reoperado y otro de
déficit de movilidad. En el grupo percutáneo hubo 4 casos con déficit de movilidad. Discusión y conclusiones: ambas
técnicas ofrecen resultados adecuados, pero con la fijación interna se obtuvieron mejores resultados respecto a movilidad,
fuerza, mayor facilidad para realización de las actividades previas y retorno a las laborales y deportivas, a pesar
de las complicaciones inherentes a la cirugía abiertaObjectives: comparison of outcomes with internal fixation versus percutaneous fixation. Material
and Methods: retrospective case-control study of 58 metacarpal fractures (43 patients). Shaft fractures without joint
involvement were included. Exclusion criteria were involvement of the thumb or phalange, open fracture, or more
than 3 fractures in the same hand. There were 26 fractures treated with internal fixation and 32 with percutaneous
fixation. With a mean follow-up of 2,5 years (range, 1-4), functional evaluation was performed by total active motion
(TAM), strength grip, DASH, pain VAS, and radiographic results. Results: satisfactory outcomes were obtained with
both treatments. Consolidation time and radiographic alignment were similar. All clinical objective and subjective
assessments were better in the internal fixation group, as well as the rate of return to previous activities. In the internal
fixation group, there was one case with nonunion, which was reoperated, and other with lack of motion. In the
percutaneous group, there were 4 cases with mobility deficits. Discussion and conclusions: satisfactory results were
offered by both methods, but better outcomes were obtained by internal fixation with regard to motion, strength, best
facility for previous activities, and return to work and sport activities. All this was spite of the inherent complications of open surger
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