695 research outputs found
Desarrollo de herramientas de búsqueda en los archivos históricos de la CompañÍa de Jesús
El trabajo de los historiadores es pesado y difícil ya que consiste, fundamentalmente, en la localización, análisis e interpretación de documentos antiguos. Estos documentos, cuando están disponibles para su consulta, deben ser leídos uno por uno y todas las posibles referencias cruzadas, revisadas una por una. La Compañía de Jesús llegó a la Nueva España en el siglo XV y trabajó en colegios, misiones, parroquias y hospitales a lo largo de todo el continente hasta la expulsión de la Orden en 1767.
Durante este tiempo, la Compañía de Jesús puso en marcha un sistema de comunicación conocido como las Cartas Anuales o Cartas Annuas que el Provincial enviaba al General de la Compañía en Roma. Cada una de las Cartas Anuales relataba las actividades llevadas a cabo por miembros de la Compañía. Para ayudarse a redactar cada Carta y con el fin de circular la información en toda la Provincia de la Nueva España, cada uno de los encargados de las obras enviaba al Provincial una o varias cartas conocidas como Puntos de Annua.
La Compañía de Jesús, junto con el Archivo General de la Nación y el Instituto Nacional de Antropología e Historia se dio a la tarea de recopilar todas las Cartas Anuales escritas desde que los jesuitas llegaron a la Nueva España hasta su expulsión en 1767. Esta búsqueda resultó en más de 13000 folios que debieron paleografiarse para ayudar a la investigación histórica sobre la Compañía de Jesús.
Como resultado de este trabajo de recuperación y paleografía y para facilitar el acceso y manejo de los documentos, se decidió crear una herramienta informática que ofreciera a los investigadores un motor de búsqueda para hacer referencias cruzadas rápida y fácilmente, así como el acceso a los documentos a través de índices temáticos.
El desarrollo de esta herramienta presentó varios problemas técnicos que se han ido solucionando. Por ejemplo, la necesidad de que los documentos en formato electrónico siguieran fielmente las reglas de la paleografía. Este requerimiento hizo necesaria la realización de un filtro para manipular los archivos en formato XML. Se desarrolló también la interfaz gráfica para acceder a los índices temáticos y el motor de búsqueda para realizar referencias cruzadas en una o varias palabras, continuas o discontinuas en el texto del documento.
La herramienta ha sido bien recibida por los investigadores y se ha decido aumentarla con algoritmos de Text-Mining para aumentar las capacidades de la búsqueda así como la generación de referencias cruzadas entre los documentos.ITESO, A.C
Evolución de las yeserías de los Patios del Yeso y del Sol del Real Alcázar de Sevilla a través de las fuentes escritas, reforzadas por ensayos de caracterización
Static and Dynamic Properties of a Viscous Silica Melt Molecular Dynamics Computer Simulations
We present the results of a large scale molecular dynamics computer
simulation in which we investigated the static and dynamic properties of a
silica melt in the temperature range in which the viscosity of the system
changes from O(10^-2) Poise to O(10^2) Poise. We show that even at temperatures
as high as 4000 K the structure of this system is very similar to the random
tetrahedral network found in silica at lower temperatures. The temperature
dependence of the concentration of the defects in this network shows an
Arrhenius law. From the partial structure factors we calculate the neutron
scattering function and find that it agrees very well with experimental neutron
scattering data. At low temperatures the temperature dependence of the
diffusion constants shows an Arrhenius law with activation energies which
are in very good agreement with the experimental values. With increasing
temperature we find that this dependence shows a cross-over to one which can be
described well by a power-law, D\propto (T-T_c)^gamma. The critical temperature
T_c is 3330 K and the exponent gamma is close to 2.1. Since we find a similar
cross-over in the viscosity we have evidence that the relaxation dynamics of
the system changes from a flow-like motion of the particles, as described by
the ideal version of mode-coupling theory, to a hopping like motion. We show
that such a change of the transport mechanism is also observed in the product
of the diffusion constant and the life time of a Si-O bond, or the space and
time dependence of the van Hove correlation functions.Comment: 30 pages of Latex, 14 figure
Population inversion of a NAHS mixture adsorbed into a cylindrical pore
A cylindrical nanopore immersed in a non-additive hard sphere binary fluid is
studied by means of integral equation theories and Monte Carlo simulations. It
is found that at low and intermediate values of the bulk total number density
the more concentrated bulk species is preferentially absorbed by the pore, as
expected. However, further increments of the bulk number density lead to an
abrupt population inversion in the confined fluid and an entropy driven
prewetting transition at the outside wall of the pore. These phenomena are a
function of the pore size, the non-additivity parameter, the bulk number
density, and particles relative number fraction. We discuss our results in
relation to the phase separation in the bulk.Comment: 7 pages, 8 Figure
Monte Carlo Methods for Estimating Interfacial Free Energies and Line Tensions
Excess contributions to the free energy due to interfaces occur for many
problems encountered in the statistical physics of condensed matter when
coexistence between different phases is possible (e.g. wetting phenomena,
nucleation, crystal growth, etc.). This article reviews two methods to estimate
both interfacial free energies and line tensions by Monte Carlo simulations of
simple models, (e.g. the Ising model, a symmetrical binary Lennard-Jones fluid
exhibiting a miscibility gap, and a simple Lennard-Jones fluid). One method is
based on thermodynamic integration. This method is useful to study flat and
inclined interfaces for Ising lattices, allowing also the estimation of line
tensions of three-phase contact lines, when the interfaces meet walls (where
"surface fields" may act). A generalization to off-lattice systems is described
as well.
The second method is based on the sampling of the order parameter
distribution of the system throughout the two-phase coexistence region of the
model. Both the interface free energies of flat interfaces and of (spherical or
cylindrical) droplets (or bubbles) can be estimated, including also systems
with walls, where sphere-cap shaped wall-attached droplets occur. The
curvature-dependence of the interfacial free energy is discussed, and estimates
for the line tensions are compared to results from the thermodynamic
integration method. Basic limitations of all these methods are critically
discussed, and an outlook on other approaches is given
On the role of triethylene glycol in the preparation of highly active Ni-Mo/Al2O3 hydrodesulfurization catalysts: A spectroscopic study
The interaction of triethylene glycol (TEG) with alumina and its role in preparing improved NiMo/Al2O3
hydrodesulfurization catalysts was investigated by spectroscopic methods. The FT-IR study shows that
TEG is mainly adsorbed on the corners and edges of the alumina microcrystals where the strongest
Lewis sites and the higher OH frequency hydroxyl groups are mainly located. It is also observed that
the Mo O stretching vibration of surface molybdenyl groups in the oxide catalyst precursor is shifted
down in the presence of TEG, indicating a lower interaction with the alumina surface. The IR spectra of
CO adsorbed on the reduced/sulfided NiMo/Al2O3 catalysts confirm that the amount of promoted phase
(NiMoS sites) increases in the samples prepared with TEG. Accordingly, the activity measurements in the
HDS of 4,6-dimethyldibenzothiophene show that the catalyst prepared with TEG is more active than the
one prepared without it. It is proposed that TEG and its decomposition products, formed upon heating
(mainly acetates) occupy preferably the strongly interacting edge and corner sites of the alumina crystals,
forcing the Mo and Ni species to migrate mainly to the less reactive plane faces. This weakens the metalsupport
interaction allowing a better sulfidation and, at the same time, favoring the Ni\u2013Mo interaction
and the formation of the promoted NiMoS phase
Scientific culture through Final Thesis in bachelor degree
Resúmenes IV Congreso VetDoc de Docencia Veterinaria, León 2017 (6-7 de Julio)[ES] Durante el curso 2015-16 se ha llevado a cabo una experiencia innovadora en la Facultad de Veterinaria de la Universidad de Zaragoza consistente en la realización de dos Trabajos Fin de Grado (TFG) que, manteniendo su objetivo y carácter académico, han contribuido además a difundir las líneas de investigación sobre las que se trabaja en la Facultad, mediante sendos blogs temáticos desarrollados específicamente y de forma complementaria, dentro del ámbito de la divulgación científica
New contributions to the geographical distinction of painted andalusi plinths
[EN] Few examples remain of artistic Andalusi decoration in the form of painted plinths in residential settings. Several technological issues have arisen when noting potential connections in an attempt to contextualize the styles, geography and chronologies of these plinths. Using XRD, FTIR and stratigraphic analysis, and considering previous research, the study of execution techniques and materials observed in plinths in Baŷŷāna (Almería) has made it possible to establish parallels with decorated plinths from the Barrio de casas de la Alcazaba in Malaga. Based on these results, interesting conclusions can be drawn regarding production techniques which are in keeping with the survival of certain execution procedures of Roman origin for renderings. Furthermore, the existence of a production nucleus grouping the examples from Almería and Malaga is proposed within a technical context which would set them apart.[ES] Una manifestación artística de la decoración andalusí de la que se conservan escasos testimonios son los zócalos pintados en el ámbito doméstico. Los intentos por contextualizar estilística, geográfica y cronológicamente estos zócalos han planteado algunas cuestiones de índole tecnológica a la hora de apuntar posibles conexiones. El estudio de las técnicas de ejecución y materiales empleados en zócalos de Baŷŷāna (Almería), mediante análisis estratigráfico, DRX y FTIR, ha permitido establecer paralelismos con zócalos decorados procedentes del barrio de casas de la Alcazaba de Málaga a partir de una investigación anterior. Los resultados permiten extraer interesantes conclusiones sobre las técnicas de elaboración, que son congruentes con la pervivencia de algunos procedimientos de ejecución de los enlucidos de raigambre romana. Además, se plantea aquí la existencia de un núcleo de producción que agruparía los ejemplos provenientes de Almería y Málaga, cuyo contexto técnico los diferenciaría.Alejandre Sánchez, FJ.; Núñez Guerrero, C.; Díaz Ramos, S.; Pérez-Malumbres Landa, A. (2023). Nuevas aportaciones a la diferenciación geográfica de los zócalos pintados andalusíes. Loggia, Arquitectura & Restauración. (36):40-51. https://doi.org/10.4995/loggia.2023.1996940513
Geochemical study of products associated with spontaneous oxidation of coal in the Cerro Pelado Formation, Venezuela
The aim of this research work is a geochemical, mineralogical, and textural characterization of spontaneously smouldered coal-derived products in northwestern Venezuela (Cerro Pelado Formation, some
10 km from Pedregal city). Several solid samples were collected from this formation, six of unweathering
coal, an other six of resulting unmelted rocks forming on a surface coal bed, and the last four of mineralizations found accumulating around gas vents. The fresh coal and the unmelted material were analysed
by scanning electron microscopy, X-ray diffraction, and proximate techniques. Products such as magnetite and chabazite-K were identified in the alteration rocks. Likewise, both materials were also studied in
order to determine the mobilization of 17 elements into the environment; such elements were analysed
through inductively coupled plasma atomic emission spectroscopy on extracts obtained by a sequential
extraction method: each sample was firstly extracted with MilliQ water and then the resultant residue
was washed. This and the subsequently resulting residues are extracted according to the mentioned procedure by using, respectively, ammonium acetate, chlorhydric acid, peroxide and chlorhydric acid, nitric
acid and fluorhydric acid, and nitric acid. The studied elements are classified as highly mobile (Na, Ni, ...),
nearly immobile (Ti, P) and partially mobile (Mg, Fe, K,...). In regards to mineralizations around fumaroles
associated with smoldering coal seams, Fourier-transform infrared spectroscopy and X-ray diffraction
analyses have revealed the presence of salammoniac, mascagnite and other solid combustion compounds
formed by reaction of gas emitted from coal oxidation, in addition to previously non-reported sulfur-rich
by-products associated with gas fissures, particularly ammonium thiosulfate, a phase first obtained only
synthetically in the laboratory. Another objective of the research was to collect and analyse gases escaping from surficial vents. Relatively high concentrations of several aromatic compounds were detected in
the gas collected at the studied coal outcrop, as well as aliphatic hydrocarbons including ethane, propane,
butanes, among others. High contents of carbon monoxide, methane and carbon dioxide were also measured for gas samples
Age norms for grating acuity and contrast sensitivity in children using eye tracking technology
Key messages: Visual acuity is the most used method to assess visual function in children. Contrast sensitivity complements the information provided for visual acuity, but it is not commonly used in clinical practice. Digital devices are increasingly used as a method to evaluate visual function, due to multiple advantages. Testing with these devices can improve the evaluation of visual development in children from a few months of age. Visual acuity and contrast sensitivity tests, using eye tracking technology, are able to measure visual function in children across a wide range of ages, objectively, quickly and without need of an experienced examiner. Purpose: To report age-normative values for grating visual acuity and contrast sensitivity in healthy children using a digital device with eye tracking technology and to validate the grating acuity test. Methods: In the first project of the study, we examined healthy children aged between 6 months and 7 years with normal ophthalmological assessment. Grating visual acuity (VA) and contrast sensitivity (CS) were assessed using a preferential gaze paradigm with a DIVE (Device for an Integral Visual Examination) assisted with eye tracking technology to provide age norms. For the validation project, we compared LEA grating test (LGT) with DIVE VA in a group of children aged between 6 months and 4 years with normal and abnormal visual development. Results: Fifty-seven children (2.86 ± 1.55 years) were examined with DIVE VA test and 44 successfully completed DIVE CS test (3.06 ± 1.41 years). Both, VA and CS values increased with age, mainly along the first two years of life. Sixty-nine patients (1.34 ± 0.61 years) were included in the DIVE VA test validation. The mean difference between LGT and DIVE VA was − 1.05 ± 4.54 cpd with 95% limits of agreement (LoA) of − 9.95–7.84 cpd. Agreement between the two tests was higher in children younger than 1 year with a mean difference of − 0.19 ± 4.02 cpd. Conclusions: DIVE is an automatic, objective and reliable tool to assess several visual function parameters in children, and it has good agreement with classical VA tests, especially for the first stage of life
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