Numerical semigroups problem list

We propose a list of open problems in numerical semigroups.Comment: To appear in the CIM Bulletin, number 33. (http://www.cim.pt/) 13 page

El contexto de la educación en la congregación salesiana: situación mundial y nuevos escenarios pedagógicos

Al hacer memoria de los rasgos típicos de la pedagogía de Don Bosco, nacida en el Valdocco del siglo XIX, descubrimos su aportación actual y significativa al mundo educativo de hoy. El santo de los jóvenes fue un hombre de acción, con fuertes intereses pedagógicos y un profundo conocimiento del momento histórico. El educador turinés ejercitó una lectura continuada y contrastada de las necesidades de los jóvenes de su tiempo, con el fin de adaptarse a ellos y encontrar las mejores respuestas posibles. En nuestros tiempos, en medio de la actual despersonalización y de la extrema subjetividad de modelos de comportamientos individuales y sociales, la modalidad constante de su acción educativo-pastoral tiene plena vigencia: la historia de la pedagogía es deudora de sus grandes intuiciones

High-resolution Smoothed Particle Hydrodynamics simulations of the merger of binary white dwarfs

We present the results of a set of high-resolution simulations of the merging process of two white dwarfs. In order to do so, we use an up-to-date Smoothed Particle Hydrodynamics code which incorporates very detailed input physics and an improved treatment of the artificial viscosity. Our simulations have been done using a large number of particles (4x10^5) and cover the full range of masses and chemical compositions of the coalescing white dwarfs. We also compare the time evolution of the system during the first phases of the coalescence with that obtained using a simplified treatment of mass transfer, we discuss in detail the characteristics of the final configuration, we assess the possible observational signatures of the merger, like the associated gravitational waveforms and the fallback X-ray flares, and we study the long-term evolution of the coalescence.Comment: 14 pages, 9 figures. Accepted for publication in Astronomy and Astrophysic

Differential elastic electron scattering cross sections for CCl₄ by 1.5–100 eV energy electron impact

We report absolute elastic differential, integral and momentum transfer cross sections for electron interactions with CCl₄. The incident electron energy range is 1.5-100 eV, and the scattered electron angular range for the differential measurements varies from 15°-130°. The absolute scale of the differential cross section was set using the relative flow technique with helium as the reference species. Comparison with previous total cross sections shows good agreement. Atomic-like behaviour in this scattering system is shown here for the first time, and is further investigated by comparing the CCl₄ elastic cross sections to recent results on the halomethanes and atomic chlorine at higher impact energies [H. Kato, T. Asahina, H. Masui, M. Hoshino, H. Tanaka, H. Cho, O. Ingólfsson, F. Blanco, G. Garcia, S. J. Buckman, and M. J. Brunger, J. Chem. Phys. 132, 074309 (2010)].This work was conducted under the support of the Japanese Ministry of Education, Sport, Culture and Technology. H.K. acknowledges the Japan Society for the Promotion of Science (JSPS) for his fellowships as grants-in-aid for scientific research. S.J.B also acknowledges the JSPS Invitation Fellowship for Research in Japan

Re-digitizing television news : adoption of digital technology, engagement, and online news distribution in Colombian television networks

Teams of online professionals working for TV news organizations are reacting to a powerful new wave of technological innovations brought by online video platform and live streaming features as these new tools are now in the hands of the laymen, particularly through social media. This digital technological trend not only has increased the interaction between television, online, and social media, but it is also changing TV formats, visual storytelling, and patterns of video news consumption, distribution, and engagement. This dissertation takes a socio-technological approach to understanding these changes and explaining how online professionals working for TV stations are implementing digital technologies into their newsrooms to distribute content and engage their audiences. This analysis unpacks the logics behind the implementation of digital technology in TV newsrooms. The study employs participant observation at two TV news organizations, Caracol News and City-ElTiempo TV, and in-depth interviews (45 people) with online professionals to understand their practices and organizational arrangements when implementing digital technologies in the adaptation of the traditional medium to the digital media ecosystem. I found that both organizational arrangements between traditional and online media, and social media technological designs conditioned the adoption of digital technology, the transition of television media to online settings, and the production of online content at Caracol News and City News-El Tiempo Television. Likewise, I found that innovative forms of online video and broadcasting are emerging from the relationship between TV news media, online media, and digital technologies. The relationship between online teams working for TV stations and online users mimics the traditional relationship between television professionals and TV viewers. Finally, I showed that news distribution and engagement—two very important actions in the current online news making process—have been absorbed by social media platforms, particularly by Facebook. In short, there is a mutual shaping between television news organizations (society) and digital technology—including social media—that is transforming the traditional medium, generating uncertainness about its future, and its contribution to society. The study sheds light on the relationship between online and traditional media, digital technology and audiences, finding that television news structures are suffering renewed transformations.Journalis

Actividad molusquicida de extractos acuosos vegetales sobre el caracol manzana pomacea canaliculata

En el Ecuador, entre el 40 y 48% de la producción de arroz se pierde a causa del ataque de Pomacea canaliculata, una de las cien especies invasivas más dañinas del mundo que actualmente ha infestado alrededor de 170.000 hectáreas del cultivo en todo el territorio nacional

Quantum dynamical calculations on the magnetization reversal in clusters of spin-1/2 particles:Resonant coherent quantum tunneling

In the present work the reversal of magnetization and the coherence of tunneling when an external magnetic field is rotated instantaneously are studied in systems of a few spin-1/2 particles described by an anisotropic Heisenberg Hamiltonian at T=0. Our calculations demonstrate that this model for small magnetic particles exhibits collective tunneling of the magnetization only for some specific resonant values of the applied magnetic field. These resonant effects occur at fields much lower than the values corresponding to the vanishing of the barrier in the Stoner-Wohlfarth model. The former model is at variance with the exact calculations presented in this paper.</p

Blockchains' federation: Developing Personal Health Trajectory-centered health systems

The current world is a globalized and connected one. Even without moving around, a person interacts with personnel from different institutions treating him as a patient in their daily life. Each of these institutions keeps their patients' data stored in their own information system, in an isolated way. Due to this, each patient has their data scattered among all these institutions and services with which she interacts along her life. This can complicate the take of the proper decision when the patient is under treatment. To solve this situation, new patient-centered health systems have been proposed as a replacement to the actual institution-centered ones, storing all health information of a patient into a unique global vision. However, some questions have arisen around the actual proposals, as who should store and maintain this vision of a given patient, and how should this information be made available for other systems. The proposal presented in this paper advocate for the achievement of a Personal Health Trajectory that can be useful both for patients and health professionals, using the concept of blockchains' federation. The proposal has been validated using 5689 records from 50 different institutions, belonging to 1156 actors