597 research outputs found
Granitos postcinemáticos de tendencia alcalina en Ossa Morena: el stock de la Cardenchosa (prov. de Córdoba)
El stock de La Cardenchosa forma part d'un grup de granits post-cinemàtics de tendència alcalina d'edat posttournaisiana i que afloren en la zona d'Ossa Morena. Aquests granits presenten com trets característics l'allargament N-S dels seus afloraments, el seu emplaçament superficial, la presència de fàcies leucocràtiques i l'íntima connexió dels jaciments de fluorita i/o barita. La composició química i menirelògica del stock de La Cardenchosa és comparada amb altres de la mateixa regió
Pegmatitas en materiales metamórficos del norte de la provincia de Córdoba. Mineralogía y posibilidades económicas
[Resumen] En relación con rocas metamórficas de edad Precámbrica y metamorfismo de grado medio-alto se han estudiado más de 60 masas de pegmatitas cuarzo-feldespáticas compuestas por cuarzo, feldespato potásico, albita, moscovita, turma1 ina, granate, biotita, menas metálicas, minerales de uranio y otros. Las masas pegmatíticas son de formas irregulares o 1entejonares subconcordantes con la esquistosidad regional más manifiesta. Sus dimensiones oscilan entre unos decímetros y decenas de metros, y su continuidad lateral su pera en algunos casos los trescientos metros. Considerando sólo las masas de potencia métrica, por sus reservas, cal idad química de sus principales especies minerales, tamaño de grano, texturas, etc. es planteable la obtención industrial de cuarzo, feldespato potásico, feldespato sódico y moscovita[Abstract] More than 60 outcrops of quartz-fe1despatic pagmatites have been studied re1ated with Precambrian metamorphic rocks of medium-high grade. The pagmatites are composed of quartz, potash fe1dspar, a1bite, muscovite, turma1 ine, garnet, biotite, ores, uranium minerals and others. The pegmatite outcrops hare irregular o lenticular forms, subparallell to the main regional schistosity. They vary in size between a few decimeters to some tens of meters, whi1e su lateral continuity exceed in sorne cases 300 meterse By taking into account on1y the outcrop of metric size, their stocks, chemica1 qual ity of the main mineral species, grain size, texture, etc., it can be planned the industrial recovery of quartz, potash feldspar, sodic fe1dspar and muscovit
Dispersive amplitude and giant CP violation in B to three light-meson decays at LHCb
The LHCb collaboration has recently reported the largest CP violation effect
from a single amplitude, as well as other giant CP asymmetries in several
-meson decays into three charmless light mesons. It is also claimed that
this is predominantly due to rescattering in the
final state, particularly in the 1 to 1.5 GeV region. In these analyses the
amplitude is by default estimated from the
elastic scattering amplitude and does not describe the existing
scattering data. Here we show how the recent
model-independent dispersive analysis of data can
be easily implemented in the LHCb formalism. This leads to a more accurate
description of the asymmetry, while being consistent with the measured
scattering amplitude and confirming the prominent role of hadronic final state
interactions, paving the way for more elaborated analyses.Comment: 9 pages, 6 figures. Minor corrections and discussions were added.
Extended appendix with an additional improved model of the S-wave. Final
version to appear in Phys.Rev.Let
Materiales silico-carbonosos en el Precámbrico de Sierra Morena
[Resumen] Se aborda, por primera vez, un estudio comparativo de las cuarcitas negras del Precámbrico de Sierra Morena, evidenciando su carácter de rocas sílico-carbonosas, asociadas a sucesiones con importantes aportes volcánicos y producidas por precipitaci6n química-bioquímica de sílice en medios marinos someros y restringidos. Se discute su distribuci6n, valor en la correlación es tratigráfica, evoluci6n textural con el aumento del metamorfismo y la deformación y algunos de los caracteres generales de su quimismo y mineralogíaAbstract] A comparative study of the black quarzites of the Precambrian of Sierra ~orena is atte~pted here for the 'first time, which reveals their character of silicacarbonaceous rocks related to succesion with important volcanic contributions and produced by chemical-biochemical precipitacion of silica in restricted and shallow marine environments. It is discussed their distribution value in .stratigraphical correlation, textural evolution with increasing rnetamorfism ando deformation, and sorne of the general character of its chemistry and mineralog
Interspecific interactions among functionally diverse frugivores and their outcomes for plant reproduction: a new approach based on camera-trap data and tailored null models
Research ArticleThe study of plant-frugivore interactions is essential to understand the ecology and evolution
of many plant communities. However, very little is known about how interactions among frugivores
indirectly affect plant reproductive success. In this study, we examined direct interactions
among vertebrate frugivores sharing the same fruit resources. Then, we inferred
how the revealed direct interspecific interactions could lead to indirect (positive or negative)
effects on reproductive success of fleshy fruited plants. To do so, we developed a new analytical
approach that combines camera trap data (spatial location, visitor species, date and
time, activity) and tailored null models that allowed us to infer spatial-temporal interactions
(attraction, avoidance or indifference) between pairs of frugivore species. To illustrate our
approach, we chose to study the system composed by the Mediterranean dwarf palm, Chamaerops
humilis, the Iberian pear tree, Pyrus bourgaeana, and their shared functionally
diverse assemblages of vertebrate frugivores in a Mediterranean area of SW Spain. We first
assessed the extent to which different pairs of frugivore species tend to visit the same or different
fruiting individual plants. Then, for pairs of species that used the same individual
plants, we evaluated their spatial-temporal relationship. Our first step showed, for instance,
that some prey frugivore species (e.g. lagomorphs) tend to avoid those C. humilis individuals
that were most visited by their predators (e.g. red foxes). Also, the second step revealed
temporal attraction between large wild and domestic frugivore ungulates (e.g. red deer,
cows) and medium-sized frugivores (e.g. red foxes) suggesting that large mammals could
facilitate the C. humilis and P. bourgaeana exploitation to other smaller frugivores by making
fruits more easily accessible. Finally, our results allowed us to identify direct interaction pathways,
that revealed how the mutualistic and antagonistic relations between animal associates
derived into indirect effects on both plants seed dispersal success. For instance, we
found that large-sized seed predators (e.g. ungulates) had a direct positive effect on the likelihood
of visits by legitimate seed dispersers (e.g. red foxes) to both fleshy fruited plants.
Then, seed predators showed an indirect positive effect on the plants’ reproductive Our new analytical approach provides a widely applicable framework for further studies on
multispecies interactions in different systems beyond plant-frugivore interactions, including
plant-pollinator interactions, the exploitation of plants by herbivores, and the use of carcasses
by vertebrate scavengersinfo:eu-repo/semantics/publishedVersio
Pensamiento formal y rendimiento en física. Análisis de la validez del test de Longeot por referencia a tests de rendimiento
Proyecto de enseñanza individualizada de ciencias experimentales (PEICE). Análisis de una experiencia
EL VIDEOJUEGO COMO RECURSO DIDÁCTICO EN EL APRENDIZAJE DE LA GEOGRAFÍA. UN ESTUDIO DE CASO
The effects of a simulation videogame (CAESAR III) on the geographical learning process of a student are shown. Although there are still some unsolved questions, an increase of the motivation for the significative learning, an improvement of the concepts’ understanding and a development of the problem-solving skills as well as of the creative thought has been noted.Se presentan aquí los efectos de un videojuego de simulación (CAESAR III) en el proceso de aprendizaje geográfico de un alumno. Aunque quedan aún cuestiones sin resolver, se ha podido constatar un aumento de la motivación para el aprendizaje significativo, una mejora de la comprensión de los conceptos y un desarrollo tanto de las habilidades para la resolución de problemas como del pensamiento creativo
- …