Continuity properties of a factor of Markov chains

Starting from a Markov chain with a finite alphabet, we consider the chain obtained when all but one symbol are undistinguishable for the practitioner. We study necessary and sufficient conditions for this chain to have continuous transition probabilities with respect to the past

DIFERENTES PERCEPCIONES DE UN MISMO AMBIENTE: LA CUESTIÓN DEL GÉNERO EN LA ENSEÑAZA DE LA CIENCIA

This paper relates some considerations resulting from a thesis study in Biological Sciences held at Universidade Estadual Paulista - Unesp, Bauru Campus. Considering the perceptual act endowed with simultaneous actions of the cognitive apparatus and the individual's life history as the merleau-pontyana phenmomenon tells us, the work aimed to identify how boys and girls in elementary school realize a natural savanna. The study was realized with the extension project "Walking and learning at the cerrado” in the Center for Memory and Dissemination of Science and Technology (CDMCT) of Postgraduate Education for Science in the same institution. Classes were held in these practical activities, monitored by undergraduate and graduate students, and, the project focuses on students from public and private schools in Bauru and region, and other visiting groups. Data collection was performed using the representations in the form of free drawings of students of their environment after the activity. Through qualitative and quantitative analysis, the results allowed us to highlight differences in the way in which genders perceived and thus represented the fragment of cerrado vegetation. The male drawings contained a larger amount of non-living elements, whereas the representations by women, besides their botanical details, often drew on animals and people. The framework of the drawings by the boys took the nearest way, whereas by the girls more often considered the representations and the entire context of the site visited. So, we emphasize the need for further discussions within the perception of the environment to consider differences in the representations of boys and girls within the context of the teaching of natural sciences, seeking, however, to avoid unsubstantiated preconceptions that may cause any degree of discrimination

Covariant Poisson Brackets in Geometric Field Theory

We establish a link between the multisymplectic and the covariant phase space approach to geometric field theory by showing how to derive the symplectic form on the latter, as introduced by Crnkovic-Witten and Zuckerman, from the multisymplectic form. The main result is that the Poisson bracket associated with this symplectic structure, according to the standard rules, is precisely the covariant bracket due to Peierls and DeWitt.Comment: 42 page

Sociopolitical life in cultural markets in the city of Porto Alegre

As possibilidades das tecnologias de informação e comunicação conjugadas com normas e regras do sistema global têm contribuído para a transformação dos mercados culturais, recriando concepções e arranjos entre arte-tecnologia-mercado. O artigo discute centralmente as implicações sociopolíticas dessas transformações nos mercados culturais, enfocando as respostas dos agentes em distintas instâncias de ação política na cidade de Porto Alegre. Os dados resultam da combinação de diferentes fontes de investigação, destacando-se entrevistas com líderes profissionais e com gestores de empreendimentos no mundo da cultura, assim como relatórios e documentos obtidos em diversos sites na Internet. O argumento que orienta a análise é de que as referidas transformações tendem a produzir diferentes tipos de ações sociopolíticas, como as mobilizações de novos coletivos de artistas, de novas associações profissionais e a reformulação de pautas nas já existentes, e a presença em novos e antigos conselhos de políticas públicas.The possibilities of information and communication technologies combined with norms and rules of the global system have contributed to the transformation of cultural markets, recreating conceptions and arrangements between art-technology-market. The article discusses the sociopolitical implications of these transformations in the cultural markets, focusing the responses of the agents in different instances of political action in the city of Porto Alegre. The data are the result of a combination of different sources of research, including interviews with professional leaders and entrepreneurs in the world of culture, as well as reports and documents obtained from various websites. The argument that guides the analysis is that these transformations tend to produce different types of sociopolitical actions, such as mobilizations of new collective artists, new professional associations and reformulation of guidelines in associations previously existing, and presence in new and old public policy councils

Art and technology in the markets : questions for discussion and analysis

Há hoje uma profícua produção científica de distintas especialidades, em diferentes países, registrando não apenas a expansão, mas também a transformação de mercados de artes e de bens e serviços culturais. Com base em uma revisão da literatura especializada, o presente artigo analisa algumas questões de interesse sociológico que se vêm debatendo sobre as recentes transforma-ções nesses mercados. A conclusão mais geral sugere que o curso de tais transformações econômicas se sustenta em diferentes formas de enraizamento sociopolítico e institucional, relativizando tanto os enfoques que atribuem ao mecanismo de mercado uma força avassaladora quanto aque-les que o concebem como a resposta mais eficiente na geração e alocação de recursos.There is, today, a fruitful scientific production of different specialties, in different countries, regis-tering not only the expansion, but also the transformation of art markets and cultural goods and services. Based on a review of the specialized literature, this article analyzed some questions of sociological interest that have been debated about the recent transformations in these markets. The main conclusion suggests that the course of such economic transformations is supported by different forms of socio-political-institutional embeddedness, relativizing both the approaches that attribute an overwhelming force to the market mechanism and the approaches that see it as the most efficient response in the generation and allocation of resources