Algunas consideraciones del alza de la azúcar en la República Dominicana

Introducción La estructura económica y social  de la República Dominicana, se alteró radicalmente, en los últimos veinticinco años del siglo XIX. A mitad de siglo, la economía de Santo Domingo era de subsistencia. Su sector externo se limitaba a la exportación de ganado a Haití y a pequeñas cantidades de productos forestales a Europa. Sin embargo, ya para fines de siglo Santo Domingo había alcanzado la economía exportadora de hoy: azúcar, café, tabaco y frutas tropicales para el mercado mundial.

Nueva luz sobre el origen de la guerra de la Triple Alianza

Introducción Este trabajo tiene tres objetivos claramente marcados: el primero, recordar el insigne amigo, cuyas paginas esclarecedoras  tanto nos han enseñado respecto al pasado de su patria, el Paraguay. El segundo, dar otro paso mas hacia el conocimiento de la verdad, respecto  de  los hechos coyunturales que dieron origen a la contienda mas cruenta en la historia moderna de la América Latina, que sumió el pueblo paraguayo en una nueva depresión económica, demográfica y social, similar a  la que experimenta durante el  largo régimen de Gaspar Rodríguez de Francia. Por ultimo, nos mueve un afán  propedéutico, dedicado a los alumnos de la cátedra de Metodología de la Universidad Nacional de Costa Rica.

El Golpe de Estado de 1917

Introducción El golpe de Estado de 1917, el periódico “La Información” en su primera pagina destacaba con grandes titulares los sucesos políticos ocurridos el día anterior, esto era el 27 de enero, fecha de importantes acontecimientos en nuestra historia patria

Formas en la tenencia de la tierra en Costa Rica durante el régimen colonial

Introducción El territorio actual de Costa Rica comprende alrededor de cincuenta mil kilómetros cuadrados de superficie y dentro de el es  posible hallar diversas condiciones ecológicas. Predominan las llanuras húmedas y cálidas  en  la región oriental y el sureste y mas al norte, o sea  en las márgenes meridionales del Lago de Nicaragua y la ribera derecha del rio San Juan. Son cálidas y secas durante parte del año, las del noroeste, que comprende la actual provincia de Guanacaste y el área oriental del Golfo de Nicoya. El Valle Central ocupa una depresión estructural  divergente, y se caracteriza por su clima templado; hay en las marcadas diferencias que son el resultado de las influencias oceánicas. Por el  este son las que provienen del Caribe; las del oeste del Pacifico.  No en vano ha dejado señalado el sabio Pittier, que el clima general de país es marítimo mas que continental, como resultado de hallarse dentro de la franja ístmica del continente americano.

La inmigración China

Introducción La población China de Costa Rica representa hoy un sector importante en la  población total. Este sector no solo esta integrado por aquellos de origen puramente chino, sino también por una cantidad importante de personas, descendiente de casamientos mixtos de chinos con costarricenses de origen hispánico, indígena o africano. La importancia cada vez  de la historia social ha despertado interés por descubrir los orígenes de ese grupo racial en Costa Rica, como forma de llegar  a una estimación de su influencia  pasada y actual en la sociedad.

Flower morpho-anatomy in Epiphyllum phyllanthus (Cactaceae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The importance of a good relationship between patient/dentist based on the obtaining of an informed consenr to prevent lawsuits

The increased number of law suits in the Dentistry field constitutes an international trend. Patients well informed by the media and supported by the law sue their dentists, when they judge they were victim of bad practice. Professionals even with all discussion about this subject do not have the habit of prevent themselves. It is known that for a defensive practice the best way to avoid litigation is a good relationship with patient, based on dialog and on informed consent. This relation is very important, since patients who rely on their dentists rarely take them to justice. Hence, this article discusses the importance of this relation, as well as the obtaining of informed consent in order to prevent lawsuits.

Establishing common elements among some science education references as a resource to design a Didactics of Physics program for teachers initial education

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Future Brazilian teachers imaginaries about physics teaching in adults education

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Physics teachers initial education and professional performance: what do future teachers have to say?

This research deals with the discussion about Physics teachers’ undergraduate education and professional performance related to the knowledge acquired during this initial education. More specifically, we try to answer questions like: How do future teachers evaluate the knowledge acquired during their initial education as in terms of specific knowledge as pedagogical knowledge? What are their formative needs and future expectatives about professional performance and the school teaching environment? Data was constituted from a sample of 26 future high school physics teachers, one semester long, that were taking the supervised curricular training in a undergraduate Physics education program (called Licenciatura in Brazil), in São Paulo State public university. Besides the final report of this training, future teachers were asked to answer a questionnaire aiming to take their conceptions about their initial education program, their formative needs, future professional expectatives and high school teaching environment. According to the future teachers, the program they were about to finish was satisfactory in terms of Physics specific contents; however, about the pedagogical content knowledge and the pedagogical practice, they showed to be unsatisfied and insecure. The majority of the questionnaire responses demonstrated that they feel lack of teaching experience. Moreover, teachers emphasize other factors related to the future professional performance: possible difficulties to deal with students’ indiscipline, schools’ bad physical structure, limited number of Physics classes in high school level, lack of didactical laboratories and also they seem to be frightened that the expertise teachers do not be collaborative with the new ones. In this sense, the research outcomes shows the necessity of discussions about questions involving teachers knowledge, related to either, the Physics conceptual domain and the pedagogical one, since it matters directly to future teachers professional performance. Discussions in this sense can also help evaluation and restructuration of programs designed to initial and continuous teachers’ education.

Accurate ab initio potential energy surfaces for the (3)A '' and (3)A ' electronic states of the O(P-3) plus HBr system

In this work, we report the construction of potential energy surfaces for the (3)A '' and (3)A' states of the system O(P-3) + HBr. These surfaces are based on extensive ab initio calculations employing the MRCI+Q/CBS+SO level of theory. The complete basis set energies were estimated from extrapolation of MRCI+Q/aug-cc-VnZ(-PP) (n = Q, 5) results and corrections due to spin-orbit effects obtained at the CASSCF/aug-cc-pVTZ(-PP) level of theory. These energies, calculated over a region of the configuration space relevant to the study of the reaction O(P-3) + HBr -> OH + Br, were used to generate functions based on the many-body expansion. The three-body potentials were interpolated using the reproducing kernel Hilbert space method. The resulting surface for the (3)A '' electronic state contains van der Waals minima on the entrance and exit channels and a transition state 6.55 kcal/mol higher than the reactants. This barrier height was then scaled to reproduce the value of 5.01 kcal/mol, which was estimated from coupled cluster benchmark calculations performed to include high-order and core-valence correlation, as well as scalar relativistic effects. The (3)A' surface was also scaled, based on the fact that in the collinear saddle point geometry these two electronic states are degenerate. The vibrationally adiabatic barrier heights are 3.44 kcal/mol for the (3)A '' and 4.16 kcal/mol for the (3)A' state. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4705428]

Image Reconstruction Using Interval Simulated Annealing in Electrical Impedance Tomography

Electrical impedance tomography (EIT) is an imaging technique that attempts to reconstruct the impedance distribution inside an object from the impedance between electrodes placed on the object surface. The EIT reconstruction problem can be approached as a nonlinear nonconvex optimization problem in which one tries to maximize the matching between a simulated impedance problem and the observed data. This nonlinear optimization problem is often ill-posed, and not very suited to methods that evaluate derivatives of the objective function. It may be approached by simulated annealing (SA), but at a large computational cost due to the expensive evaluation process of the objective function, which involves a full simulation of the impedance problem at each iteration. A variation of SA is proposed in which the objective function is evaluated only partially, while ensuring boundaries on the behavior of the modified algorithm.

Geschichte der Israeliten : mit besonderer Berücksichtigung der Culturgeschichte derselben ; von Alexander dem Großen bis auf die neuere Zeit

nach den besten vorhandenen Quellen bearb. von Julius Heinrich Dessauer

La Revue scientifique.

Vols. for July 1884-Dec. 1944 have subtitle: Revue rose (varies slightly)

The Franco-German war 1870-1871,

Translation of part 1 of "Krieg und sieg, 1870-71", edited by Julius von Pflugk-Harttung, first published Berlin, 1895.