Three stories with common inspiration: A comparative studie regarding teacher education policies in South America

In this work we investigate one of the most relevant aspects of educational policies in this region, such as teacher training. From a regional comparative perspective, in the first place, some conceptual categories (regional, regionalism) are defined that allow to establish lines of inquiry between the processes of international educational transfers between these countries. Secondly, it addresses the normative definitions that regulate the educational systems and especially those destined to the educational formation during the last decades in the three countries studied. Finally, some conjectures about the scope and limitations of the reform processes are establishedEn este trabajo se indaga sobre uno de los aspectos más relevantes de las políticas educativas en esta región como son las de formación del profesorado. Desde una perspectiva comparativa regional, en primer lugar, se definen algunas categorías conceptuales (región, regionalismo) que permiten establecer líneas de indagación entre los procesos de transferencias educativas internacionales entre estos países. En segundo lugar, se abordan las definiciones normativas que regulan los sistemas educativos y especialmente aquellas destinadas a la formación docente durante las últimas décadas en los tres países estudiados. Finalmente, se establecen algunas conjeturas sobre los alcances y limitaciones de los procesos de reforma

Regional Business Cycles and National Economic Borders - What are the Effects of Trade in Developing Countries?

Does trade lead to increased cross-country regional business cycle synchronization and reduced national economic borders? The theory does not really provide an unambiguous answer. Our paper addresses empirically this question using Argentina and Brazil as case studies of developing countries. These countries liberalized unilaterally trade since the mid-1980s and also established MERCOSUR (a regional integration agreement with Paraguay and Uruguay) in 1991. As a consequence, the intensity of trade between Argentina and Brazil rose significantly. The answer to the initial question is no. The increase in bilateral trade between Argentina and Brazil did not translate into significantly more synchronized regional business cycles. Using Gross Provincial Product for Argentina and Gross State Product for Brazil for the period 1961 to 2000, we find that within-country regional business cycle synchronization is substantially larger than cross-country regional business cycle synchronization. Moreover, this difference has increased over time. These results are mainly driven by Argentina’s behavior and hold even after controlling for factors such as distance, size, sectoral specialization, and the degree of regional fiscal policy coordination. The empirical evidence based on Brazilian states and Argentina as a whole suggests that the higher level of trade among regions within a country is an important factor to that accounts for the observed border effect. In the case of Argentina additional factors such as monetary and exchange rate policies and large country-specific shocks have also played a significant role.

Field-controlled suppression of phonon-induced transitions in coupled quantum dots

We calculate the longitudinal-acoustic phonon scattering rate for a vertical double quantum dot system with weak lateral confinement and show that a strong modulation of the single-electron excited states lifetime can be induced by an external magnetic or electric field. The results are obtained for typical realistic devices using a Fermi golden rule approach and a three-dimensional description of the electronic quantum states.Comment: REVTex4 class, 6 pages, 3 figures, to be published in Applied Physics Letter

Unified Fock space representation of fractional quantum Hall states

Many bosonic (fermionic) fractional quantum Hall states, such as Laughlin, Moore-Read and Read-Rezayi wavefunctions, belong to a special class of orthogonal polynomials: the Jack polynomials (times a Vandermonde determinant). This fundamental observation allows to point out two different recurrence relations for the coefficients of the permanent (Slater) decomposition of the bosonic (fermionic) states. Here we provide an explicit Fock space representation for these wavefunctions by introducing a two-body squeezing operator which represents them as a Jastrow operator applied to reference states, which are in general simple periodic one dimensional patterns. Remarkably, this operator representation is the same for bosons and fermions, and the different nature of the two recurrence relations is an outcome of particle statistics.Comment: 10 pages, 3 figure

Building, Testing and Assessing a Learning Management System

This paper summarizes the experiences of our research group in managing the full process of building, testing and assessing a Learning Management System for a educational institution. We will show how we moved across the “make or buy” dilemma that normally educational institutions have to face when deciding to implement a support for online and distance learning activities. We will deal with this theme by referring to systems and prototypes developed by our research group. Specifically, we will describe our experiences in realizing systems for making didactic material available on Internet, such as in the Learning Management Systems - LMS. This experience is based on what has been developed, tested, and put to use in some faculties of the University of Trento, where non-traditional learning environments in which students require more than the traditional face-to-face lessons are becoming ever more important. The prototypes produced are based on platform-independent technologies, and they make it possible to broaden one’s horizons, even for those students, such as lifelong learners, who want freedom from time constraints and also freedom from some technological constraints that are imposed by some forms of distance education currently available on the market. Some extensions to mobile tools like PDA, tablet PC, cellular phones etc. are presented, with regards to the impact of their introduction on the LMS and in general on the information system of the institution

Selberg integrals in 1D random Euclidean optimization problems

We consider a set of Euclidean optimization problems in one dimension, where the cost function associated to the couple of points $x$ and $y$ is the Euclidean distance between them to an arbitrary power $p\ge1$, and the points are chosen at random with flat measure. We derive the exact average cost for the random assignment problem, for any number of points, by using Selberg's integrals. Some variants of these integrals allows to derive also the exact average cost for the bipartite travelling salesman problem.Comment: 9 pages, 2 figure

Un Análisis sobre las Políticas de Integración Productiva en el MERCOSUR

En los últimos años, el MERCOSUR comenzó a plantear la integración productiva como política regional (IPR), incorporando a las PyMEs en el centro de la escena. Luego de comparar con la experiencia de otros bloques (NAFTA, ASEAN, UE), este trabajo analiza los (aunque aún escasos) avances de las iniciativas sectoriales de IPR. Las (varias) propuestas e iniciativas de IPR entre PyMEs han sido muchas y de distintos orígenes y sectores, con la mayoría apuntando a encadenamientos verticales entre una empresa ancla y sólo algunas a la integración horizontal, y todas ellas (salvo logística y transporte) se refi eren a la producción de bienes y no de servicios. Así, encontramos que las iniciativas que más avanzaron fueron claramente lideradas por una empresa ancla o cámaras empresariales, y/o contaron con apoyo del sector privado (como mecanismo superador de los confl ictos gubernamentales) y/o financiamiento. Por último, observamos un cambio en la óptica y visión por parte de los actores involucrados, centrando sus expectativas en demandas de mínima más que de máxima. Este trabajo está organizado en cuatro partes. En la primera presentamos los conceptos y los principales hallazgos de la literatura sobre IPR, para luego hacer un recorrido histórico sobre las distintas iniciativas, alcances y antecedentes de la IPR en el MERCOSUR. Una tercera sección describe y analiza las diversas propuestas que se están diseñando e implementando en la actualidad sobre la materia en el ámbito del MERCOSUR, para concluir con algunas reflexiones que aporten para el futuro del proceso.In recent years, MERCOSUR began to raise the productive integration as a regional policy (IPR), incorporating SMEs in the center of the scene. After comparing with the experience of other blocs (NAFTA, ASEAN, EU), this paper analyzes advances (although still rare) in the IPR sectors initiatives. The (several) IPR proposals and initiatives among SMEs have been a lot and from different backgrounds and sectors, with most pointing to vertical linkages between a firm anchor and just some horizontal integration, and all them (except logistics and transport) refers to the production of goods and services. Thus, we find that the most advanced initiatives were clearly led by anchor company or business chambers, and/or were supported private sector (as a mechanism overcomes the governmental conflicts) and/or financing. Finally, we note a change in optics and vision of the actors involved, focusing their demands in minimum expectations rather than maximum. This paper is organized in four parts. In the first part, we present the concepts and the main findings of the literature on IPR and then we make a historical overview of the various initiatives, scope and history of the IPR in MERCOSUR. In the third section we describe and analyze the various proposals that are being designed and implemented at present on the subject in MERCOSUR, to conclude with some thoughts that contribute to the future of the process.Fil: Botto, Mercedes Isabel. Facultad Latinoamericana de Ciencias Sociales. Sede Académica Argentina Buenos Aires. Area de Relaciones Internacionales. Programa de Instituciones Económicas Internacionales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Molinari, Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Internacional de Economía Política de Buenos Aires; Argentina. Universidad de San Andres; Argentin

Reduced electron relaxation rate in multi-electron quantum dots

We use a configuration-interaction approach and Fermi golden rule to investigate electron-phonon interaction in realistic multi-electron quantum dots. Lifetimes are computed in the low-density, highly correlated regime. We report numerical evidence that electron-electron interaction generally leads to reduced decay rates of excited electronic states in weakly confined quantum dots, where carrier relaxation is dominated by the interaction with longitudinal acoustic phonons.Comment: to appear in Phys. Rev. Let

Triplet-Singlet Spin Relaxation in Quantum Dots with Spin-Orbit Coupling

We estimate the triplet-singlet relaxation rate due to spin-orbit coupling assisted by phonon emission in weakly-confined quantum dots. Our results for two and four electrons show that the different triplet-singlet relaxation trends observed in recent experiments under magnetic fields can be understood within a unified theoretical description, as the result of the competition between spin-orbit coupling and phonon emission efficiency. Moreover, we show that both effects are greatly affected by the strength of the confinement and the external magnetic field, which may give access to very long-lived triplet states as well as to selective population of the triplet Zeeman sublevels.Comment: 5 pages, 3 figures. Closely related to recent experiments in cond-mat/060972

Latent dirichlet allocation model for world trade analysis

International trade is one of the classic areas of study in economics. Its empirical analysis is a complex problem, given the amount of products, countries and years. Nowadays, given the availability of data, the tools used for the analysis can be complemented and enriched with new methodologies and techniques that go beyond the traditional approach. This new possibility opens a research gap, as new, data-driven, ways of understanding international trade, can help our understanding of the underlying phenomena. The present paper shows the application of the Latent Dirichlet allocation model, a well known technique in the area of Natural Language Processing, to search for latent dimensions in the product space of international trade, and their distribution across countries over time. We apply this technique to a dataset of countries exports of goods from 1962 to 2016. The results show that this technique can encode the main specialisation patterns of international trade. On the countrylevel analysis, the findings show the changes in the specialisation patterns of countries over time. As traditional international trade analysis demands expert knowledge on a multiplicity of indicators, the possibility of encoding multiple known phenomena under a unique indicator is a powerful complement for traditional tools, as it allows top-down data-driven studies.Fil: Kozlowski, Diego. University of Luxembourg; LuxemburgoFil: Semeshenko, Viktoriya. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Interdisciplinario de Economía Política de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Económicas. Instituto Interdisciplinario de Economía Política de Buenos Aires; ArgentinaFil: Molinari, Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Interdisciplinario de Economía Política de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Económicas. Instituto Interdisciplinario de Economía Política de Buenos Aires; Argentin