Wave Equations for Classical Two-Component Proca Fields in Curved Spacetimes with Torsionless Affinities

The world formulation of the full theory of classical Proca fields in generally relativistic spacetimes is concisely reviewed and the entire set of pertinent field equations is transcribed in a straightforward way into the framework of one of the Infeld-van der Waerden formalisms. Some well-known calculational techniques are then utilized for deriving the wave equations that control the propagation of the fields allowed for. It appears that no interaction couplings between such fields and electromagnetic curvatures are carried by the wave equations at issue. What results is, in effect, that the only interactions which ultimately occur in the theoretical context under consideration involve strictly Proca fields and wave functions for gravitons.Comment: Many improvements on the paper have still been made. In particular, its title has been modified so as to conform further to one of its main aim

Occupational Risks: Perceptual Map Construction using psychometric paradigm and multivariate methods

Risk management focus main on technical and rational analysis about operational risks and by those imposed by occupational environment. In this work one looks to contribute to perception study of work safety professionals about a series of activities and environment agents. In this way it was used theory sustained by psychometric paradigm and multivariate analysis tools, mainly multidimensional scaling, generalized Procrustes analysis and facet theory, in order to construct the perceptual map of occupational risks. The results obtained showed that the essential characteristics of risks, which were initially split in 4 facets were detected and maintained in perceptual map. The construction of perceptual map also permitted to verify the formation of a new facet, not considered in the beginning. The facet theory which by hypothesis was used in this work showed adequate, providing the regional interpretation of the map. The inferential analysis realized showed fine results for the final configuration validation, indicating which risks and/or activities belongs to the same facet.

(INTER)PERSONAL STATEMENTS: A DISCURSIVE ANALYSIS OF COLLEGE APPLICATION ESSAYS WRITTEN IN ENGLISH BY US AMERICAN AND BRAZILIAN STUDENTS

The field of discourse analysis has produced extensive research on various aspects of genres that permeate everyday life as well as on the specialized discourses of academic and professional communities. Nevertheless, there is a dearth of studies on the personal statement, which, despite being a key genre of the admissions processes to globalized (and English language-dominated) institutions of higher education, remains unexplored in Brazilian educational culture. The present study addresses this gap by examining samples of this unique genre produced by US American and Brazilian students admitted to English-language universities. The analysis principally draws from Dominique Maingueneau’s scholarship on the “scene” of a genre and the Bakhtin Circle’s ideas on the social and generic nature of utterances. The main purpose is to compare and contrast rhetorical appeals to ethos and pathos made by both groups of students engaged in the high-stakes enterprise of writing about their values, beliefs, and goals with unknown readers/evaluators in mind. The results shed light on some of the linguistic and intercultural challenges that Brazilian students face when communicating in English within unfamiliar scenes of writing, the knowledge of which can shed light on ways to facilitate successful intercultural communication

Understanding the technological and pedagogical content knowledge (TPACK) of mathematics teachers as a possibility for reflection on the use of educational technology

Background: the broader access to technological resources, combined with pedagogical practices implementation, shows the need of continuing education of teachers on digital information and communication technologies (DICT). Recognizing the knowledge that professionals need in their work is a path that allows the evaluation and creation of training measures. Objectives: considering the pedagogical and technological content knowledge (TPACK) as a reference, we sought to investigate the professional knowledge of mathematics teachers about digital technological resources and their possible incorporation in pedagogical practices. Design: a qualitative research was carried out. Setting and participants: mathematics teachers working in high school, technical and higher education who participated in a short-term training proposal. Data collection and analysis: the research was based on meetings with mathematics teachers, in which the use of resources was discussed and lesson plans were elaborated; they were, then, followed up in a real scenario. Specific instruments, lesson plans, audiovisual records, and interviews were analyzed by textual discursive analysis (TDA), provided evidence about teachers’ use of resources. Results: different professional knowledge linked to TPACK were recognized at different levels and some factors such as professional experience and technological appropriation proved to be influential. Conclusions: in addition to the possibility of recognizing professional knowledge, it was noted that a specific character under the interpretation of TPACK recognizes such knowledge even in teachers with a low level of technology appropriation, which allowed reflections on the construct itself and its possible correlations with the pedagogical content knowledge (PCK)

Relações de produção na pecuária leiteira: um estudo de caso das respostas da produção aos preços mensais

It is intended to verify the relations between input and products concerning to replaceability or complementarity, as well as the impacts of monthly variations on product prices (milk and meat) and input (fuels, work, concentrate) in the production system in Brazil that possess cows of 2.000 to 3.000 kilograms of milk for nursing. The results show that monthly variations in prices paid or received by producers cause considerable monthly changes in the markets for milk and the input considered.Profit translog function, Prices, Dairy cattle, Demand and Price Analysis,

Environmental Licensing Challenges of Xingu Rio Transmission System Route Definition

Based on the Brazilian electric sector planning, by 2026 the transmission grid will be increased by 64 thousand km, so that the analysis of how to incorporate the environmental criteria in the discussions of route optimization are important for the decision-making of the various actors (government, environmental agencies and entrepreneurs). Therefore, this article aims to identify the challenges of the incorporation of the socio-environmental criteria for the route optimization as well as the deadlines and costs of the Xingu-Rio Transmission System known to be the largest transmission system in Brazil