1,926 research outputs found
Ernest Renan among us : from antichrist to prophet
El historiador francés Ernest Renan (1823-1892) publicó en 1863 una Vida de Jesús que cuestionaba la divinidad del mismo. Causó escándalo e intentos de refutación. Se estudian algunas reacciones en América Latina y se describe el proceso por el cual Renan llegó posteriormente a ser aceptado por círculos conservadores.The French historian Ernest Renan (1823-1892) published in 1863 a Life of Jesus that questioned his divinity. The book aroused scandal and attempts of rebuttal. This analysis examines some of the reactions in Latin America, as well as the process by which Renan came later to be accepted in conservative
circles.Fil: Taboada, Hernán G. H..
Universidad Nacional Autónoma de Méxic
From African Spain to Theocratic America : notes on the Ideas of Simón Bolívar
Las ideas de Simón Bolívar sobre América y sobre Europa han recibido alguna
atención de los investigadores. Mucho menos las que expresó sobre Asia y
África. Aunque fueron marginales a su pensamiento, la reunión de sus alusiones
al respecto permite arrojar alguna luz sobre la reflexión de la Independencia
y sobre los cambios que el Libertador experimentó en su percepción
del naciente mundo que aparecía ante sus ojos. Partiendo de una actitud
orientalista y despectiva inicial, con el tiempo llegó a pensar que el Oriente
no podía descartarse como influencia en las instituciones americanas.Simón Bolivar’s ideas regarding America and Europe have attracted some
attention from academic researchers, but much less so those regarding
Asia and Africa. Even though they were secondary to his thought, gathering
these references allows us to throw some light on Bolivar’s and his Hispanic-
American contemporaries’ views on Independence, and on the changes in the
Libertador’s perception of the nascent American world taking shape before
his eyes. Departing from an Orientalist and contemptuous attitude at first,
Bolivar eventually arrives at the idea that the “Orient" could not be dismissed
as an influence over American institutions.Fil: Taboada, Hernán G. H.
Counterfactual Density Estimation using Kernel Stein Discrepancies
Causal effects are usually studied in terms of the means of counterfactual
distributions, which may be insufficient in many scenarios. Given a class of
densities known up to normalizing constants, we propose to model counterfactual
distributions by minimizing kernel Stein discrepancies in a doubly robust
manner. This enables the estimation of counterfactuals over large classes of
distributions while exploiting the desired double robustness. We present a
theoretical analysis of the proposed estimator, providing sufficient conditions
for consistency and asymptotic normality, as well as an examination of its
empirical performance
Snap-8 corrosion program quarterly progress report, period ending 28 feb. 1965
SNAP-8 corrosion program - hydrogen solubility in sodium-potassium, permeability of hydrogen and deuterum through stainless steel, and phase equilibri
An Efficient Doubly-Robust Test for the Kernel Treatment Effect
The average treatment effect, which is the difference in expectation of the
counterfactuals, is probably the most popular target effect in causal inference
with binary treatments. However, treatments may have effects beyond the mean,
for instance decreasing or increasing the variance. We propose a new
kernel-based test for distributional effects of the treatment. It is, to the
best of our knowledge, the first kernel-based, doubly-robust test with provably
valid type-I error. Furthermore, our proposed algorithm is efficient, avoiding
the use of permutations
Quasi-equilibrium and quantum correlation in an open spin-pair system
Quasi-equilibrium states that can be prepared in solids through Nuclear
Magnetic Resonance (NMR) techniques are out-of-equilibrium states that slowly
relax towards thermodynamic equilibrium with the lattice. In this work, we use
the quantum discord dynamics as a witness of the quantum correlation in this
kind of state. The studied system is a dipole interacting spin pair whose
initial state is prepared with the NMR Jeener-Broekaert pulse sequence,
starting from equilibrium at high temperature and high external magnetic field.
It then evolves as an open quantum system within two different dynamic
scenarios: adiabatic decoherence driven by the coupling of the pairs to a
common phonon field, described within a non-markovian approach; and
spin-lattice relaxation represented by a markovian master equation, and driven
by thermal fluctuations. In this way, the studied model is endowed with the
dynamics of a realistic solid sample. The quantum discord rapidly increases
during the preparation of the initial state, escalating several orders of
magnitude compared with thermal equilibrium at room temperature. Despite the
vanishing of coherences during decoherence, the quantum discord oscillates
around this high value and undergoes a minor attenuation, holding the same
order of magnitude as the initial state. Finally, the quantum discord
dissipates within a time scale shorter than but comparable to spin-lattice
relaxation.Comment: 19 pages, 5 figure
Strain relaxation of GaAs/Ge crystals on patterned Si substrates
Taboada, A. G. et al.We report on the mask-less integration of GaAs crystals several microns in size on patterned Si substrates by metal organic vapor phase epitaxy. The lattice parameter mismatch is bridged by first growing 2-μm-tall intermediate Ge mesas on 8-μm-tall Si pillars by low-energy plasma enhanced chemical vapor deposition. We investigate the morphological evolution of the GaAs crystals towards full pyramids exhibiting energetically stable {111} facets with decreasing Si pillar size. The release of the strain induced by the mismatch of thermal expansion coefficients in the GaAs crystals has been studied by X-ray diffraction and photoluminescence measurements. The strain release mechanism is discussed within the framework of linear elasticity theory by Finite Element Method simulations, based on realistic geometries extracted from scanning electron microscopy images. © 2014 AIP Publishing LLC.Financial support by the Swiss Federal Program Nano-Tera through projects NEXRAY and COSMICMOS and Spanish MINECO and CAM through projects EPIC-NANOTICS and Q&C Light are gratefully acknowledged.Peer Reviewe
Compositional analysis of InAs-GaAs-GaSb heterostructures by low-loss electron energy loss spectroscopy
As an alternative to Core-Loss Electron Energy Loss Spectroscopy, Low-Loss EELS is suitable for compositional analysis of complex heterostructures, such as the InAs-GaAs-GaSb system, since in this energy range the edges corresponding to these elements are better defined than in Core-Loss. Furthermore, the analysis of the bulk plasmon peak, which is present in this energy range, also provides information about the composition. In this work, compositional information in an InAs-GaAs-GaSb heterostructure has been obtained from Low-Loss EEL spectra
- …