Plant neurobiology: a interspecific perspective on the debate

Este trabalho apresenta um balanço do debate ocasionado pelas ideias suscitadas nas ciências das plantas com o advento da neurobiologia das plantas, destacando, a partir das tensões geradas entre diferentes grupos de cientistas, os elementos do que Hustak & Myers (2012) chamam de uma “narrativa mais rica”, além do enfoque redutivo da biologia contemporânea sobre células e genes, ou de uma lógica evolucionista neodarwiniana, e com maior atenção ao organismo e seus modos de relação. Uma narrativa que também dê conta da maneira como as plantas se expressam e permita desvelar os emaranhados nos quais plantas e cientistas estão envolvidos. Inspirada nas ideias introduzidas no campo interespecífico pelas etnografias multiespécies, a hipótese que se coloca é a de que essas tensões, sozinhas ou combinadas, sugerem modos de acessar a perspectiva das plantas.This paper presents a balance of the debate caused by the ideas raised in plants sciences with the advent of plants neurobiology, highlighting from the tensions generated between different groups of scientists the elements of what Hustak & Myers (2012) call a “richer narrative”, beyond reductive focus of contemporary biology on cells and genes, or a neodarwinian evolutionary logic, and with greater attention to the organism and modes of relation. A narrative that also accounts for the way plants express themselves and reveal the entanglements in which plants and scientists are involved. Inspired by the ideas introduced in the interspecific field by the multispecies ethnography, the hypothesis is that these tensions, alone or in combination, suggest ways of accessing the perspective of the plants

RAPÉ E XAMANISMO ENTRE GRUPOS INDÍGENAS NO MÉDIO PURUS, AMAZÔNIA

Based on tobacco, snuff occupies a special place in shamanism among indigenous groups in the middle Purus (Amazon region). The article focuses on the use and meaning of snuff among some of these groups, contributing for the understanding of the snuff ’s role, and shamanic practices in the region, taking in account the several beings that make part of their cosmologies. The authors present a multisited study based on historical and etnographic sources. The data point to an unavoidable connection between snuff and shamanism in the middle Purus, helping to understand the various indigenous groups as a system in communica­tion, beyond historic or ethnonymic differences. Keywords: snuff, xamanism, indigenous peoples, middle Purus, Ama­zoniaFabricado com base no tabaco, o rapé ocupa um lugar especial no xamanismo entre os grupos indígenas do médio Purus (Amazônia). O texto propõe explorar o uso e sentido do rapé entre alguns desses grupos, contribuindo assim para descortinar seu papel e tecer algumas considerações preliminares acerca das práticas de xamanismo na região e da relação dos indígenas com os vários seres que habitam os universos descritos em suas cosmologias. A proposta é realizar um estudo multissituado a partir de dados obtidos em documentos históricos e relatos etnográficos sobre diferentes grupos que vivem na região. Mesmo sem um estudo que aborde de maneira transversal a questão, os dados apresentados apontam para a inevitável conexão entre o rapé e o xamanismo no médio Purus e nos ajudam a compreender a plêiade de grupos habitantes dessa região como um sistema em comunicação, apontando para uma etnologia do Purus para além das diferenças históricas ou etnonímicas. Palavras-chave: Rapé, xamanismo, grupos indígenas, médio Purus, Amazôni

Comparison of the accuracy of different transfer impression techniques for osseointegrated implants

The aim of this study was to evaluate 3 transfer techniques used to obtain working casts of implant-supported prostheses through the marginal misfit and strain induced to metallic framework. Thirty working casts were obtained from a metallic master cast, each one containing 2 implant analogs simulating a clinical situation of 3-unit implant-supported fixed prostheses according to the following transfer impression techniques: group A, squared transfers splinted with dental floss and acrylic resin, sectioned, and re-splinted; group B, squared transfers splinted with dental floss and bis-acrylic resin; and group N, squared transfers not splinted. A metallic framework was made for marginal misfit and strain measurements from the metallic master cast. The misfit between the metallic framework and working casts was evaluated with an optical microscope following the single-screw test protocol. In the same conditions, the strain was evaluated using strain gauges placed on the metallic framework. The data were submitted to one-way analysis of variance followed by the Tukey test (α = 5%). For both marginal misfit and strain, there were statistically significant differences between groups A and N (P < .01) and groups B and N (P < .01), with greater values for group N. According to the Pearson test, there was a positive correlation between the misfit and strain variables (r = 0.5642). The results of this study showed that the impression techniques with splinted transfers promoted better accuracy than the nonsplinted technique, regardless of the splinting material used41666266

Physiological changes of Arabica coffee under different intensities and durations of water stress in the Brazilian cerrado

Coffee farmers have faced problems due to drought periods, with irrigation being necessary. In this sense, this study aimed to evaluate the responses to different levels and durations of water deficit in arabica coffee genotypes in the Cerrado region. The experiment consisted of three Coffea arabica genotypes and five water regimes: full irrigation (FI 100 and FI 50—full irrigation with 100% and 50% replacement of evapotranspiration, respectively), water deficit (WD 100 and WD 50—water deficit from June to September, with 100% and 50% replacement of evapotranspiration, respectively) and rainfed (without irrigation). The variables evaluated were gas exchange, relative water content (RWC) and productivity. The results showed that during stress, plants under the FI water regime showed higher gas exchange and RWC, differently from what occurred in the WD and rainfed treatments; however, after irrigation, coffee plants under WDs regained their photosynthetic potential. Rainfed and WD 50 plants had more than 50% reduction in RWC compared to FIs. The Iapar 59 cultivar was the most productive genotype and the E237 the lowest. Most importantly, under rainfed conditions, the plants showed lower physiological and productive potential, indicating the importance of irrigation in Coffea arabica in the Brazilian Cerrado

Reseña de: A vida secreta das árvores (Wohlleben, 2017)

Peter Wohlleben. (2017). A vida secreta das árvores. Trad. de P. Rissati (título original em alemão: Das Geheime Leben der Bäume, 2015). Rio de Janeiro: Editora Sextante. 223 pp. ISBN: 9788543104652

Review of A vida secreta das árvores (Wohlleben, 2017)

Peter Wohlleben. (2017). A vida secreta das árvores. Trad. de P. Rissati (título original em alemão: Das Geheime Leben der Bäume, 2015). Rio de Janeiro: Editora Sextante. 223 pp. ISBN: 9788543104652

As capacidades institucionais das comunidades na Amazônia: a estratégia de desenvolvimento territorial do Baixo Amazonas

O projeto tem como objetivo Analisar as capacidades institucionais que possibilitam a criação de uma rede de articulação interna e externa na gestão territorial de uma comunidade amazônica, bem como o nível de maturação do capital social dos grupos sociais locais. A orientação geral da pesquisa será o trabalho etnográfico, durante o qual os dados serão coletados a partir do convívio com os sujeitos da pesquisa, além de entrevistas e análise de dados secundários. Espera-se com o resultado contribuis para a reflexão acerca dos Territórios Rurais, permitindo aos sujeitos se empoderar e pensar a realidade na qual se inserem.CNP