2,428 research outputs found
La persona como horizonte interior en la filosofía de Manuel Mindán
Las personas somos absolutamente diferentes de las cosas, no cabe ninguna duda al respecto. No obstante, sí debemos diferenciar nítidamente entre los individuos y el concepto de “persona”. Así pues, la persona posee un “horizonte interior”, absolutamente novedoso y que le caracteriza como ser en aproximación a la Verdad y a la Libertad, las cuales no sólo son específicas del propio humano, sino que le son necesarias en cuanto remedios contra la desolación y la tiranía. Asimismo, una sociedad puede ser tiránica en varios sentidos, pero Manuel Mindán sostiene que, para que no lo sea, el individuo entendido como “persona” debe primar siempre sobre el grupo gregario y cerrado.People and things are quite different, but we must distinguish clearly between individuals and the concept of “person”. So, the person possesses an “inner horizon”, completely new, and characterizes him as being on approach to Truth and Freedom -which are specific to the human itself-, while both are needed as remedies against desolation and tyranny. Likewise, a society can be tyrannical, in several senses. However, Manuel Mindán believes that the individual understood as a “person” must always prevail over the gregarious and closed group
Polarization Properties of Extragalactic Radio Sources and Their Contribution to Microwave Polarization Fluctuations
We investigate the statistical properties of the polarized emission of
extragalactic radio sources and estimate their contribution to the power
spectrum of polarization fluctuations in the microwave region. The basic
ingredients of our analysis are the NVSS polarization data, the multifrequency
study of polarization properties of the B3-VLA sample (Mack et al. 2002) which
has allowed us to quantify Faraday depolarization effects, and the 15 GHz
survey by Taylor et al. (2001), which has provided strong constraints on the
high-frequency spectral indices of sources. The polarization degree of both
steep- and flat-spectrum at 1.4 GHz is found to be anti-correlated with the
flux density. The median polarization degree at 1.4 GHz of both steep- and
flat-spectrum sources brighter than mJy is . The data by Mack et al. (2002) indicate a substantial mean Faraday
depolarization at 1.4 GHz for steep spectrum sources, while the depolarization
is undetermined for most flat/inverted-spectrum sources. Exploiting this
complex of information we have estimated the power spectrum of polarization
fluctuations due to extragalactic radio sources at microwave frequencies. We
confirm that extragalactic sources are expected to be the main contaminant of
Cosmic Microwave Background (CMB) polarization maps on small angular scales. At
frequencies GHz the amplitude of their power spectrum is expected to be
comparable to that of the -mode of the CMB. At higher frequencies, however,
the CMB dominates.Comment: 10 pages, A&A in pres
A statistical index of growth condition in an aquaculture experiment
A simple statistical index, for evaluating the condition of growth in an aquaculture experiment and indicating the extent of effect of any plausible rival hypothesis, is presented
Quantum features derived from the classical model of a bouncer-walker coupled to a zero-point field
In our bouncer-walker model a quantum is a nonequilibrium steady-state
maintained by a permanent throughput of energy. Specifically, we consider a
"particle" as a bouncer whose oscillations are phase-locked with those of the
energy-momentum reservoir of the zero-point field (ZPF), and we combine this
with the random-walk model of the walker, again driven by the ZPF. Starting
with this classical toy model of the bouncer-walker we were able to derive
fundamental elements of quantum theory. Here this toy model is revisited with
special emphasis on the mechanism of emergence. Especially the derivation of
the total energy hbar.omega and the coupling to the ZPF are clarified. For this
we make use of a sub-quantum equipartition theorem. It can further be shown
that the couplings of both bouncer and walker to the ZPF are identical. Then we
follow this path in accordance with previous work, expanding the view from the
particle in its rest frame to a particle in motion. The basic features of
ballistic diffusion are derived, especially the diffusion constant D, thus
providing a missing link between the different approaches of our previous
works.Comment: 14 pages, based on a talk given at "Emergent Quantum Mechanics (Heinz
von Foerster Conference 2011)", see
http://www.univie.ac.at/hvf11/congress/EmerQuM.htm
Terebélidos (Terebellidae: Polychaeta: Annelida) del Caribe colombiano
Polychaetes have a high diversity and abundance in all oceans. They have important role as biological indicators of marine water quality. In Colombia, they have been studied for about 30 years, in which 43 families, 138 genera and 253 species have been identified, from central and north Colombian Caribbean coasts. The aim of this research was the taxonomic analysis of material belonging to the family Terebellidae, deposited in the Invemar Invertebrate Collection. Eight genera and 11 species of terebellids were previously identified; nevertheless, after this research, these numbers were increased to ten genera, and 17 species. The scarce information about polychaetes available in Colombia, and the lack of stardardized, updated taxonomic world revisions, not only for terebellids but also for the entire group of polychaetes, led to many incorrect species identifications, and the belief that some species are cosmopolitan in distribution. Anincrease in funding of basic taxonomic research will permit better estimates of the true polychaete diversity found in Colombian seas.Los poliquetos presentan una amplia diversidad y abundancia en todos los océanos. Su principal importancia radica en su uso como indicadores de calidad del agua, ayudando a identificar contaminación marina. El estudio de estos anélidos en Colombia lleva un poco mas de 30 años, durante los cuales se ha logrado identificar 43 familias, 138 géneros y 253 especies de poliquetos, principalmente de la costa central y norte del Caribe colombiano. El propósito de esta investigación fue analizar taxonómicamente el material correspondiente a la familia Terebellidae depositado en la Colección de Invertebrados de Invemar. El análisis de los ocho géneros y 11 especies previamente reportadas para esta familia, dio como resultado un aumento en ambas categorías, pues se encontró que hay realmente diez géneros y 17 especies. La escasez de información en el país, así como de revisiones taxonómicas mundiales estandarizadas, consistentes y actualizadas, tanto de esta familia como de otras, hace que se identifiquen incorrectamente las especies, considerando algunas especies como cosmopolitas. Por lo tanto, se considera que un incremento en el apoyo a la investigación básica, que apunte hacia el conocimiento de las especies, permitirá estimar la biodiversidad que realmente poseen los mares de Colombia
Momentum distribution in heavy deformed nuclei: role of effective mass
The impact of nuclear deformation on the momentum distributions (MD) of
occupied proton states in U is studied with a phenomenological
Woods-Saxon (WS) shell model and the self-consistent Skyrme-Hartree-Fock (SHF)
scheme. Four Skyrme parameterizations (SkT6, SkM*, SLy6, SkI3) with different
effective masses are used. The calculations reveal significant deformation
effects in the low-momentum domain of states, mainly of
those lying near the Fermi surface. For other states, the deformation effect on
MD is rather small and may be neglected. The most remarkable result is that the
very different Skyrme parameterizations and the WS potential give about
identical MD. This means that the value of effective mass, being crucial for
the description of the spectra, is not important for the spatial shape of the
wave functions and thus for the MD. In general, it seems that, for the
description of MD at MeV/c, one may use any single-particle
scheme (phenomenological or self-consistent) fitted properly to the global
ground state properties.Comment: 14 pages, 6 figure
Porous Titanium surfaces to control bacteria growth: mechanical properties and sulfonated polyetheretherketone coating as antibiofounling approaches
Here, titanium porous substrates were fabricated by a space holder technique. The relationship between microstructural characteristics (pore equivalent diameter, mean free-path between pores, roughness and contact surface), mechanical properties (Young’s modulus, yield strength and dynamic micro-hardness) and bacterial behavior are discussed. The bacterial strains evaluated are often found on dental implants: Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa. The colony-forming units increased with the size of the spacer for both types of studied strains. An antibiofouling synthetic coating based on a sulfonated polyetheretherketone polymer revealed an effective chemical surface modification for inhibiting MRSA adhesion and growth. These findings collectively suggest that porous titanium implants designed with a pore size of 100–200 µm can be considered most suitable, assuring the best biomechanical and bifunctional anti-bacterial properties.University of Seville VI Plan Propio de Investigación y Transferencia—US 2018, I.3A
Protoplanetary disks in the hostile environment of Carina
We report the first direct imaging of protoplanetary disks in the star-forming region of Carina, the most distant massive cluster in which disks have been imaged. Using the Atacama Large Millimeter/sub-millimeter Array (ALMA), the disks are observed around two young stellar objects (YSOs) that are embedded inside evaporating gaseous globules and exhibit jet activity. The disks have an average radius of 60 au and total masses of 30 and 50 . Given the measured masses, the minimum timescale required for planet formation (~1–2 Myr) and the average age of the Carina population (~1–4 Myr), it is plausible that young planets are present or their formation is currently ongoing in these disks. The non-detection of millimeter emission above the 4σ threshold () in the core of the massive cluster Trumpler 14, an area containing previously identified proplyd candidates, suggests evidence for rapid photo-evaporative disk destruction in the cluster's harsh radiation field. This would prevent the formation of giant gas planets in disks located in the cores of Carina's dense subclusters, whereas the majority of YSO disks in the wider Carina region remain unaffected by external photoevaporation
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