Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Squaramide and its derivatives represent an important group of substances that are currently being successfully applied in asymmetric organocatalitic strategies, which is why this contribution presents a summary of the state of the art related to the synthesis of escuaramide derivatives and their role as chirality inducers in relevant synthetic sequences. To this end, a process of systematic search and selection of reports published in specialized journals of the area was established in order to present the most significant aspects of synthesis and the application of escuaramide derivatives in this key area of organic chemistry.

Numerous studies have shown that social perception of Science is infused with naive visions and society transmitted stereotypes. Despite the large amountof research existing in this field, most of the studies that support the existence of Science stereotypes were carried out on children and youngsters and the majority of same took place in other countries. The present work aims to reflect the social perception of Science within a group of adult people residing in Granada, Spain, and this through the analysis of 88 drawings using the “Draw a scientist test” method. As a novelty, this work includes a pilot study with the purpose to get to know if it would be possible to change this Science stereotypic perception by using pictures. The results show a certain stereotyped image of the scientist, which is similarly shown in people of different ages, sex, origin or intellectual level. In addition, this image is resistant to change.

This paper presents the implementation outcomes of the Equivalent Circuit Model (ECM) acting in conjunction with the Matrix Cascading Method (MCM) for bandwidth calculation in cross dipole Frequency Selective Surfaces (FSSs). Dielectric layers are used as a support of resonant elements in FSSs. Models of effective permittivity of the dielectric layers in FSSs allow to determine the effect of the material used as insulating support of the resonant elements, in relation to the resonant frequency and bandwidth, as a function of the thickness of the dielectric material. However, in this approach, the insulating support is considered as thin dielectric, and therefore, it is modeled as a lumped parameter. This consideration may lead to unsuitable results in calculating the bandwidth for thick dielectric supports. The novelty of the paper is the implementation of the Equivalent Circuit Model together with the Matrix Cascading Method to determine the frequency response of the cross dipole selective surface for any dielectric thickness and configuration. It is notable the low computational time as well as the acceptable accuracy obtained with the proposed approach, compared to Ansys-HFSS simulations. 

This paper presents, first different characteristic elements based on the approach of educational modelling throughout a bibliography review. Secondly, a didactic proposal consisting of a total of 29 activities was analyzed. This proposal was proposed for the study of Sun and Earth but specially in the seasons phenomenon, with teachers in starting level from primary school. The experience tried to demonstrate, how the following design would be integrated in to the education by modelling, and in consequence extract the weaknesses and strength to improve the contents and its structure.

In this article, the results on the difficulties that cause dropout of student’s informative research teams in higher education are presented. The method chosen was qualitative research with a case study, using data collection techniques interviews, document analysis, observation and field notes. Among the findings of the investigation, it was found that: the desertion (disintegration) of a research team triggers serious problems in the studies, students have difficulty research, for example in the search for information, in teamwork, and for example, they have problems of coexistence.

Editorial

The paper argues that the trajectory of the Americas Fund has validated it as a specialized institution in managing environmental issues in Chile, and that its mission springs from the commitment to two fundamental values: sustainable development and participatory democracy. The article then outlines the evaluation of their institutional policies and stresses its support for the creation and strengthening of capacities of nongovernmental organizations (NGOs) and grassroots organizations, through annual competitions as the main tool of corporate management. Then it delves into the concepts of sustainable development and civil society in relation to the new role taken by the liberal state. It also arises questions on public-private cooperation for sustainable development, and proposes new social policies and a 'new deal' with the third sector.

This paper is divided into three parts: the first reviews how current economic science was consolidated in the isolated world of exchange values, giving a hard time to economists who now seek to think about the environment; the second concerns the ecological or environmental economy, already established in the academic world, but that has failed greening ordinary economy; and finally the third part concludes pointing out the main "taboo" topics that remain ignored in this area, blocking the path to a real ecologcl reconversion of ordinary economy.

The author postulates that the formation of an environmental rationality is a process of renewal of the world, of deconstruction of the foundations of Western civilization and the fallacies of economic globalization; and that the dialogue about knowledges aims at a renaissance that will emerge from the encounter of beings that inhabit the world from within their cultures and their conditions of existence; from where rises the new in the encounter with otherness, diversity and difference; without hierarchies, up from the human right to make oneself a place in the world and to be with the others, and that beyond this underlies a recovery of a sustainable future.