Ribet bimodules and the specialization of Heegner points

We describe the specialization of Heegner points on Shimura curves at primes of bad reduction. Moreover, we give some reciprocity laws relating the Galois action on these points to natural actions on the set of singular points and the set of connected components of the fiber

Anticyclotomic p-adic l-functions and the exceptional zero phenomenon

Let A be a modular elliptic curve over a totally real field F, and let E/F be a totally imaginary quadratic extension. In the event of exceptional zero phenomenon, we prove a formula for the derivative of the multivariable anticyclotomic p-adic L-function attached to (A,E), in terms of the Hasse-Weil L-function and certain p-adic periods attached to the respective automorphic forms. Our methods are based on a new construction of the anticyclotomic p-adic L-function by means of the corresponding automorphic representation

Eichler-Shimura isomorphism and group cohomology on arithmetic groups

The Eichler-Shimura isomorphism realizes the automorphic representation generated by an automorphic newform in certain cohomology of an arithmetic group. In this short note, we give a cohomological interpretation of the Eichler-Shimura isomorphism as a connection morphism of certain exact sequence of G-modules, for the multiplicative group G of any quaternion algebra over a totally real field

Borderplex Economic Growth: Chicken, Egg, or Scrambled?

Regional debates over which metropoitan economy is the dominant growth pole in multi-city areas can be intense. Such discourse is frequently voiced with regard to economic expansion in the El Paso, Texas, USA - Ciudad Juarez, Chihuahua, Mexico borderplex economy. To date, no empirical analyses have been carried out to address that question. Granger causality tests are applied to various cross-border data to shed light on that question and others regarding the nature of regional growth in this international setting.Border economic growth, applied econometrics, population, employment

A model for high-mass microquasar jets under the influence of a strong stellar wind

Context. High-mass microquasars (HMMQs) are systems from which relativistic jets are launched. At the scales of several times the binary system size, the jets are expected to follow a helical path caused by the interaction with a strong stellar wind and orbital motion. Such a trajectory has its influence on the non-thermal emission of the jets, which also depends strongly on the observing angle due to Doppler boosting effects. Aims: We explore how the expected non-thermal emission of HMMQ jets at small scales is affected by the impact of the stellar wind and the orbital motion on the jet propagation. Methods: We studied the broadband non-thermal emission, from radio to gamma rays, produced in HMMQ jets up to a distance of several orbital separations, taking into account a realistic jet trajectory, different model parameters, and orbital modulation. The jet trajectory is computed by considering momentum transfer with the stellar wind. Electrons are injected at the position where a recollimation shock in the jets is expected due to the wind impact. Their distribution along the jet path is obtained assuming local acceleration at the recollimation shock, and cooling via adiabatic, synchrotron, and inverse Compton processes. The synchrotron and inverse Compton emission is calculated taking into account synchrotron self-absorption within the jet, free-free absorption with the stellar wind, and absorption by stellar photons via pair production. Results: The spectrum is totally dominated by the jet over the counter-jet due to Doppler boosting. Broadband emission from microwaves to gamma rays is predicted, with radio emission being totally absorbed. This emission is rather concentrated in the regions close to the binary system and features strong orbital modulation at high energies. Asymmetric light curves are obtained owing to the helical trajectory of the jets.Fil: Molina, E.. Universidad de Barcelona; EspañaFil: del Palacio, Santiago. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; ArgentinaFil: Bosch Ramon, Valentí. Universidad de Barcelona; Españ

Análisis preliminar de la dinámica poblacional y amenazas del oso andino (Tremarctos ornatus) al nor-occidente del Distrito Metropolitano de Quito (DMQ)-Ecuador

The objectives of this research were: i) Estimate the size and the structure of an andean bear population in an area within the Metropolitan District of Quito (MDQ); ii) Record displacements and characterize the habitat used by the bears; and iii) Define potential areas where socio environmental conflicts could be generated and could affect the conservation of these bears and the forests where they live. A total of 24 bears, representing all life stages and sex, where recorded and identified in an area within the MDQ, through direct observations between February-March 2008, and August-October 2009, and the use of camera traps between November 2009 and May 2010. In 2008 and 2009, 9 and 16 bears respectively were recorded in 30 hours of direct observation, divided in 86 feeding events on “aguacatillo” (Nectandra acutifolia) in the Maquipucuna reserve, showing a feeding pattern until now not recorded. In the camera traps the movements of 5 bears photographed more than two times in different sites within the study area where partially recorded. These bears moved from different areas and type of forests passing necessarily through disturbed areas with the presence of people. The lack of protection of natural remnants, the disordered use of the land, and the lack of knowledge of the population dynamics, home range and the movement patterns of these bears are threatening their survival and the integrity and connectivity of their habitat. The camera traps also captured 16 mammals species of the families: Felidae, Cervidae, Mustelidae, Tayassuidae, Procyonidae, Dasyproctidae, Cuniculidae and some species of Rodentia, which points to the importance of protecting these forests to ensure the conservation not only of the bears but also other mammals with important ecological roles.Los objetivos de esta investigación fueron: i) Estimar el tamaño y la estructura de una población de osos andinos (Tremarctos ornatus) en un área al nor occidente del DMQ; ii) Registrar desplazamientos y caracterizar el hábitat usado por los osos; y iii) Definir potenciales zonas en donde se puedan generar conflictos socio-ambientales que podrían afectar la conservación de estos osos y los bosques donde habitan. Un total de 24 osos, representando todos los estados de crecimiento y sexo, fueron registrados e identificados en un área dentro del Distrito Metropolitano de Quito, mediante observaciones directas realizadas entre Febrero-Marzo del 2008 y Agosto-Octubre 2009, y el uso de trampascámara entre Noviembre 2009 y Mayo 2010. En los años 2008 y 2009, 9 y 16 osos respectivamente fueron registrados en 30 horas de observación directa, divididas en 86 eventos de alimentación con aguacatillo o pacche (Nectandra acutifolia) en la reserva Maquipucuna, evidenciando un patrón de alimentación hasta ahora no reportado. En las cámaras trampa se registró parcialmente el movimiento de 5 individuos los cuales fueron fotografiados más de dos veces en distintos lugares a lo largo del área de estudio. Estos osos se desplazaron por diferentes áreas y tipos de bosques teniendo que atravesar obligadamente por zonas alteradas y con presencia humana. La falta de protección de los remantes naturales, el uso desordenado del suelo, y la falta de conocimiento sobre el tamaño de las áreas de vida, la dinámica poblacional y los patrones de movimiento de estos osos, han puesto en peligro su supervivencia y la integridad y conectividad del hábitat donde viven. Las trampas cámara también capturaron a 16 especies de mamíferos de las familias: Felidae, Cervidae, Mustelidae, Tayassuidae, Procyonidae, Dasyproctidae, Cuniculidae y varias especies del orden Rodentia, lo cual apunta a la importancia de proteger estos bosques para asegurar la conservación no solo del oso andino sino también de otros mamíferos con importantes roles ecológicos

Ribet Bimodules and the Specialization of Heegner points

For a given order R in an imaginary quadratic field K, we study the specialization of the set CM(R) of Heegner points on the Shimura curve X = X0(D,N) at primes p | DN. As we show, if p does not divide the conductor of R, a point P in CM(R) specializes to a singular point (resp. a connected component) of the special fiber Xp of X at p if p ramifies (resp. does not ramify) in K. Exploiting the moduli interpretation of X0(D,N) and K. Ribet’s theory of bimodules, we give a construction of a correspondence between CM(R) and a set of conjugacy classes of optimal embeddings of R into a suitable order in a definite quaternion algebras that allows the explicit computation of these specialization maps. This correspondence intertwines the natural actions of Pic(R) and of an Atkin-Lehner group on both sides. As a consequence of this and the work of P. Michel, we derive a result of equidistribution of Heegner points in Xp. We also illustrate our results with an explicit example.Postprint (published version