La dimensión transgubernamental en la integración latinoamericana : el caso de Argentina y Bolivia con sus países limítrofes

El presente trabajo se enmarca, dentro de la teoría de las relaciones internacionales, en el llamado “Paradigma de la Interdependencia compleja", por ello adoptamos como concepto de relación transgubernamental el aportado por los principales autores de esta corriente, quienes las definen como “contactos entre las burocracias gubernamentales encargadas de tareas similares" (Keohane R. O. y Nye J. S.: 1988). Para estos autores, la unidad de análisis ya no es el Estado, el cual pierde su carácter de actor principal, sino que serían las organizaciones intergubernamentales (como la ONU y otras), las ONGs, las multinacionales, las organizaciones subestatales e incluso los individuos. Las tres características centrales de ésta teoría serían entonces: 1) analizar los canales múltiples que conectan a las sociedades, a través de relaciones interestatales, transgubernamentales y transnacionales, con la participación de diversas organizaciones no directamente controladas por gobiernos, 2) afirmar que la agenda de las relaciones interestatales se encuentra constituida por múltiples temas sin jerarquía rígida. Los problemas energéticos, de los recursos, del medio ambiente, de la población, del empleo del espacio y de los mares se equiparan ahora con cuestiones de seguridad militar, ideológicas y de rivalidad territorial, las que tradicionalmente habían conformado la agenda diplomática y los análisis realistas, 3) considerar que la fuerza militar no es usada dentro de regiones de influencia de cada Estado sino más bien contra gobiernos fuera de ellas

Symmetry, bifurcation and stacking of the central configurations of the planar 1+4 body problem

In this work we are interested in the central configurations of the planar 1+4 body problem where the satellites have different infinitesimal masses and two of them are diametrically opposite in a circle. We can think this problem as a stacked central configuration too. We show that the configuration are necessarily symmetric and the other sattelites has the same mass. Moreover we proved that the number of central configuration in this case is in general one, two or three and in the special case where the satellites diametrically opposite have the same mass we proved that the number of central configuration is one or two saying the exact value of the ratio of the masses that provides this bifurcation.Comment: 9 pages, 2 figures. arXiv admin note: text overlap with arXiv:1103.627

Convex central configurations of the 4-body problem with two pairs of equal masses

Agraïments: The first and third authors are partially supported by FAPEMIG grant APQ-001082/14. The third author is partially supported by CNPq grant 472321/2013-7 and by FAPEMIG grant PPM-00516-15. The second and third autors are supported by CAPES CSF-PVE grant 88881.030454/2013-01.MacMillan and Bartky in 1932 proved that there is a unique isosceles trapezoid central configuration of the 4--body problem when two pairs of equal masses are located at adjacent vertices. After this result the following conjecture was well known between people working on central configurations: The isosceles trapezoid is the unique convex central configuration of the planar 4--body problem when two pairs of equal masses are located at adjacent vertices. We prove this conjecture

Four-body co-circular central configurations

We classify the set of central configurations lying on a common circle in the Newtonian four-body problem. Using mutual distances as coordinates, we show that the set of four-body co-circular central configurations with positive masses is a two-dimensional surface, a graph over two of the exterior side-lengths. Two symmetric families, the kite and isosceles trapezoid, are investigated extensively. We also prove that a co-circular central configuration requires a specific ordering of the masses and find explicit bounds on the mutual distances. In contrast to the general four-body case, we show that if any two masses of a four-body co-circular central configuration are equal, then the configuration has a line of symmetry.Peer ReviewedPostprint (author’s final draft

Deep incision in an Aptian carbonate succession indicates major sea-level fall in the Cretaceous

Long-term relative sea-level cycles (0 5 to 6 Myr) have yet to be fully understood for the Cretaceous. During the Aptian, in the northern Maestrat Basin (Eastern Iberian Peninsula), fault-controlled subsidence created depositional space, but eustasy governed changes in depositional trends. Relative sea-level history was reconstructed by sequence stratigraphic analysis. Two forced regressive stages of relative sea-level were recognized within three depositional sequences. The first stage is late Early Aptian age (intra Dufrenoyia furcata Zone) and is characterized by foreshore to upper shoreface sedimentary wedges, which occur detached from a highstand carbonate platform, and were deposited above basin marls. The amplitude of relative sea-level drop was in the order of tens of metres, with a duration of 2 km wide and cut 115 m down into the underlying Aptian succession. With the subsequent transgression, the incision was back-filled with peritidal to shallow subtidal deposits. The changes in depositional trends, lithofacies evolution and geometric relation of the stratigraphic units characterized are similar to those observed in coeval rocks within the Maestrat Basin, as well as in other correlative basins elsewhere. The pace and magnitude of the two relative sea-level drops identified fall within the glacio-eustatic domain. In the Maestrat Basin, terrestrial palynological studies provide evidence that the late Early and Late Aptian climate was cooler than the earliest part of the Early Aptian and the Albian Stage, which were characterized by warmer environmental conditions. The outcrops documented here are significant because they preserve the results of Aptian long-term sea-level trends that are often only recognizable on larger scales (i.e. seismic) such as for the Arabian Plate

Etude hydrobiologique des eaux du Taron (Commune de Theux, Province de Liège, Belgique)

Le ruisseau du Turon est formé par un chevelu complexe de ruisselets provenant de sources et/ou de résurgences, situés pour la plupart à l'ouest du village de La Reid. Ce travail a pour objet l'étude de la qualité, essentiellement biologique, de ces petits cours d'eau. Il présente les principaux résultats d'un travail de fin d'étude à l'Institut Supérieur d'Agronomie de La Reid (CORS, 2003), mené en près de trente stations, de fin mars 2002 à fin mars 2003. LERUTH (1939) avait déjà étudié les sources de la région et y avait recensé plusieurs espèces stygobies, garantes de la qualité des eaux souterraines. Nous avons tenté de les retrouver

Interpretation of magnetization measurement data obtained on hot pressed Pb_1-xSn_xMo₆S₈ samples

Magnetization measurements have been carried out on samples prepared with varied Sn contents, using constant parallel applied field sweep rates in the range of 30 to 190 mT/s. The hysteresis loops observed up to about 6 T at 4.2 K are earmarked by characteristic flux jump phenomena. J/sub c/ critical current densities deduced from the loop widths can be interpreted, in agreement with the fine analyses of the loops, in terms of global critical screening currents, related to very good connectivity between the grains