1,321 research outputs found
The significance of «S-C» structures found in the Berzosa-Honrubia region (Spanish Central System)
[Resumen] En el extremo oriental del Sistema Central Español, existen evidencias de un episodio tect6nico fini -hercínico, que se manifiesta en el desarrollo de una banda de 1 a 2 Km de anchura, de dirección submeridiana y buzamiento al este en la que son frecuentes estructuras de tipo «S-C» dúctiles. Esta banda probablemente extensional, se superpone a la estructura singular de segunda fase hercínica (D2), conocida como Zona de Cizalla de Berzosa (Z.C.B.,
CAPOTE, R. et alters, 1981; GONZALEZ CASADO,]. M., 1986), tradicionalmente interpretada como un cabalgamiento dúctil hacia el noroeste retrovergido por la fase de pliegues longitudinales D3. La zona descrita coincide además espacialmente con una banda donde existen procesos hidrotermales tardíos, los cuales podrían relacionarse genéticamente con la estructura citada. El probable episodio extensional descrito, puede relacionarse con la etapa de extensión regional generalizada que se desarrolla durante el final del ciclo hercínico
en toda la cadena. Período este bien reflejado en muchos puntos del Sistema Central Español, en forma de importantes accidentes tectónicos extensionales, principalmente de dirección este-oeste y buzamiento norte o sur.[Abstract] In the east end of the Spanish Central System there are sorne evidence of a latehercynian tectonic event. Field evidences includes the presence of «S» and «C» planes (composite planar fabrics), in a band of 1 or 2 Km of wide, with an eastwest direction and dipping to the east. This area has probable an extensional origin and has been superimposed to a structure related to the herc.ynian second phase (D2) know as the Berzosa Shear Zone (B.S.Z., CAPOTE, R., et alters, 1981; GONZALEZ CASADO, J. M., 1986). The B.S.Z. has ben interpreted as a ductil thrust towards the nort-oest, backfolded by a phase of longitudinal folds 03. The investigated region shows a spatial correlation with a band where there are sorne late hidrotermal process, what could be genetic related with the studied structure. Microstructural evidence are internally consistent with field observations. It appears that data are compatible with N-S oriented extensional detachment, dipping to the east, with and east-under-west sense of movement. This event could be correlated with a period of regional extension found elsewhere in the Spanish Central System. Developped for aH the belt during the end of the hercynian cicle. This last even is weH developped in several points of the Spanish Central System and can be seen as severa! E-W oriented detachment systems, dipping to the N and S (extensional tectonics)
A numerical study of interactions and stellar bars
For several decades it has been known that stellar bars in disc galaxies can
be triggered by interactions, or by internal processes such as dynamical
instabilities. In this work, we explore the differences between these two
mechanisms using numerical simulations. We perform two groups of simulations
based on isolated galaxies, one group in which a bar develops naturally, and
another group in which the bar could not develop in isolation. The rest of the
simulations recreate 1:1 coplanar fly-by interactions computed with the impulse
approximation. The orbits we use for the interactions represent the fly-bys in
groups or clusters of different masses accordingly to the velocity of the
encounter. In the analysis we focus on bars' amplitude, size, pattern speed and
their rotation parameter, . The latter is used to
define fast (). Compared with
equivalent isolated galaxies we find that bars affected or triggered by
interactions: (i) remain in the slow regime for longer; (ii) are more boxy in
face-on views; (iii) they host kinematically hotter discs. Within this set of
simulations we do not see strong differences between retrograde or prograde
fly-bys. We also show that slow interactions can trigger bar formation.Comment: 12 pages, 7 figures. Accepted for publication in MNRA
Pulling and Stretching a Molecular Wire to Tune its Conductance
A scanning tunnelling microscope is used to pull a polythiophene wire from a
Au(111) surface while measuring the current traversing the junction. Abrupt
current increases measured during the lifting procedure are associated to the
detachment of molecular sub-units, in apparent contradiction with the expected
exponential decrease of the conductance with wire length. \textit{Ab initio}
simulations reproduce the experimental data and demonstrate that this
unexpected behavior is due to release of mechanical stress in the wire, paving
the way to mechanically gated single-molecule electronic devices
Hydrothermal alteration in granites from La Cabrera (Spanish Central System). Study of secondary minerals (SEM) in halos of calcium bearing mineral druses
Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasFALSEEspaña. Ministerio de Educación y Cienciapu
Shape and kinematics of elliptical galaxies: evolution due to merging at z < 1.5
[EN]Aims. We investigate the evolution in the shape and kinematics of elliptical galaxies in a cosmological framework.
Methods. We identified relaxed, elliptical-like objects (ELOs) at redshifts z = 0, z = 0.5, z = 1 and z = 1.5 within a set of hydrodynamic, self-consistent simulations completed for a concordance cosmological model.
Results. The population of elliptical systems that we analysed evolve systematically with time becoming rounder in general by z = 0 and also more velocity dispersion supported. We found that this is due primarily to major dry mergers where only a modest amount of angular momentum is involved in the merger event. Despite the general trend, in a significant number of cases the merger event involves a relatively high amount of specific angular momentum, which causes the system in general to acquire higher rotational support and/or a more oblate shape. These evolutionary patterns persist when we study our systems in projection, in simulating true observations, and thus should be evident in future observations.Peer reviewe
Hemolytic activity and siderophore production in different aeromonas species isolated from fish
P. 5612-5614The hemolytic activity and siderophore production of several strains of motile aeromonads were determined.
The hemolytic activity of Aeromonas caviae and Aeromonas eucrenophila was enhanced after trypsinization of the
samples. The enhancement of hemolysis was observed in strains that carried an aerolysin-like gene, detected
by a PCR procedure. Siderophore production was demonstrated in all but one strain of Aeromonas jandaei. No
apparent relationship was observed between the presence of plasmid DNA and hemolysis or siderophore
production.S
Evolution induced by dry minor mergers onto fast-rotator S0 galaxies
We analysed collisionless N-body simulations of intermediate and minor dry
mergers onto S0s to test whether these mergers can generate S0 galaxies with
kinematics intermediate between fast and slow rotators. We find that minor
mergers induce a lower decrease of the global rotational support than
encounters of lower mass ratios, which results in S0s with properties
intermediate between fast and slow rotators. The resulting remnants are
intrinsically more triaxial, less flattened, and span the whole range of
apparent ellipticities up to . They do not show
lower apparent ellipticities in random projections than initially; on the
contrary, the formation of oval distortions and the disc thickening increase
the percentage of projections at . In the
experiments with S0b progenitor galaxies, minor mergers tend to spin up the
bulge and to decrease slightly its intrinsic ellipticity, whereas in the cases
of primary S0c galaxies they keep the rotational support of the bulge nearly
constant and decrease significantly its intrinsic ellipticity. The remnant
bulges remain nearly spherical (), but exhibit a wide range
of triaxialities (). In the plane of global anisotropy of
velocities () vs. intrinsic ellipticity (),
some of our models extend the linear trend found in previous major merger
simulations towards higher values, while others
depart from it. This is consistent with the wide dispersion exhibited by real
S0s in this diagram compared with ellipticals, which follow the linear trend
drawn by major merger simulations. The different trends exhibited by
ellipticals and S0 galaxies in the - diagram may
be pointing to the different role played by major mergers in the build-up of
each morphological type.Comment: Corrected typos. 20 pages, 14 figures. Accepted for publishing in A&
Análisis y ejecución de estrategias en la industria de sensores mediante la simulación CAPSIM
Documento en el que se muestra el trabajo realizado en la dirección de una empresa de la industria de sensores dentro del simulador de negocios Capsim. Se presenta un análisis de la industria de los sensores, se describe la empresa en la que se trabajó, las estrategias de negocio y el proceso de su implementación, así como los resultados finales
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