Automatic crater detection using DEM and circular coherency analysis - A case study on South American craters

Accepted versio

Probing the stellar initial mass function with high-z supernovae

The first supernovae (SNe) will soon be visible at the edge of the observable universe, revealing the birthplaces of Population III stars. With upcoming near-infrared missions, a broad analysis of the detectability of high-z SNe is paramount. We combine cosmological and radiationtransport simulations, instrument specifications and survey strategies to create synthetic observations of primeval core-collapse (CC), Type IIn and pair-instability (PI) SNe with the James Webb Space Telescope (JWST). We show that a dedicated observational campaign with theJWST can detect up to ~15 PI explosions, ~300 CC SNe, but less than one Type IIn explosion per year, depending on the Population III star formation history. Our synthetic survey also shows that ≈1-2 × 102 SNe detections, depending on the accuracy of the classification, are sufficient to discriminate between a Salpeter and flat mass distribution for high-redshift stars with a confidence level greater than 99.5 per cent. We discuss how the purity of the sample affects our results and how supervised learning methods may help to discriminate between CC and PI SNe. © 2014 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society

The overlooked potential of Generalized Linear Models in astronomy-II: Gamma regression and photometric redshifts

Machine learning techniques offer a precious tool box for use within astronomy to solve problems involving so-called big data. They provide a means to make accurate predictions about a particular system without prior knowledge of the underlying physical processes of the data. In this article, and the companion papers of this series, we present the set of Generalized Linear Models (GLMs) as a fast alternative method for tackling general astronomical problems, including the ones related to the machine learning paradigm. To demonstrate the applicability of GLMs to inherently positive and continuous physical observables, we explore their use in estimating the photometric redshifts of galaxies from their multi-wavelength photometry. Using the gamma family with a log link function we predict redshifts from the PHoto-z Accuracy Testing simulated catalogue and a subset of the Sloan Digital Sky Survey from Data Release 10. We obtain fits that result in catastrophic outlier rates as low as ~1% for simulated and ~2% for real data. Moreover, we can easily obtain such levels of precision within a matter of seconds on a normal desktop computer and with training sets that contain merely tho nds of galaxies. Our software is made publicly available as a user-friendly package developed in Python, R and via an interactive web application. This software allows users to apply a set of GLMs to their own photometric catalogues and generates publication quality plots with minimum effort. By facilitating their ease of use to the astronomical community, this paper series aims to make GLMs widely known and to encourage their implementation in future large-scale projects, such as the Large Synoptic Survey Telescope

New detrital petrographic and thermochronologic constraints on the Late Cretaceous-Neogene erosional history of the equatorial margin of Brazil: Implications for the surface evolution of a complex rift margin

The equatorial margin of Brazil is an example of a rift margin with a complex landscape, dominated by an escarpment perpendicular to the continental margin, which testifies to an equally complex rift and post-rift surface and tectonic evolution. This has been the focus of a long debate on the driving mechanism for post-rift tectonics and on the amount of exhumation. This study contributes to this debate with new petrographic and thermochronologic data on 152 samples from three basins, Para-Maranhao, Barreirinhas and Ceara, on the offshore continental platform. Our detrital record goes back to the rift time at ca. 100 Ma ago and outlines three major evolutionary phases of a changing landscape: a rift phase, with the erosion of a moderate rift escarpment, a Late Cretaceous-Palaeogene post-rift phase of major drainage reorganization and significant vertical erosion and a Late Oligocene-to-Recent post-rift phase of moderate vertical erosion and river headwater migration. We estimate that along the equatorial margin of Brazil, over a large onshore area, exhumation since the Late Cretaceous has totalled locally up to 2-2.5 km and since the late Oligocene did not exceed 1 km

Uma releitura a propósito da responsabilidade civil ambiental: de uma responsabilidade civil para além da figura do dano

RESUMO: O presente artigo enfrenta a problemática da responsabilidade civil na área do direito ambiental.  Partindo de um direito fundamental a um meio ambiente equilibrado, enfrenta-se os aspectos mais controvertidos no âmbito da responsabilidade civil ambiental, dentre eles o princípio do poluidor-pagador, o princípio da precação, as figuras da prescrição e da solidariedade e a própria noção de responsabilização civil na matéria ambiental, ainda que ausente a figura do dano. Para tanto, adota-se o método dedutivo de pesquisa, estruturando o presente trabalho com base em uma análise crítica de doutrinas e legislações nacionais e estrangeiras que enfrentam a matéria, de forma a definir critérios da responsabilidade civil ambiental.PALAVRAS-CHAVE: dano ambiental; responsabilidade ambiental; princípio do poluidor pagador; responsabilidade civil ambiental;ABSTRACT: The present article faces the problematic of the civil responsibility on the environmental field. Starting from a fundamental right to balanced environment, it’s faced the most controverted aspects in the field of the civil environmental responsibility, between them the polluter pays principle, the precaution principle, the figures of prescription and solidarity and the notion itself of civil responsibility in environmental subject, even with the absence of the damage figure. For that, it’s adopted the deductive method of research, structuring the present paper in a critic analysis of national and foreigner doctrine and legislation that faces the subject, in a way to define criteria of civil environmental responsibility.KEYWORDS: environmental damage; environmental responsibility; polutter pays principle; civil environmental responsibility; Submetido em: 04-04-2017Aprovado em: 14-07-201

Modelling the chemical recycling of crosslinked poly (methyl methacrylate): kinetics of depolymerisation

Whereas increasing plastic solid waste production constitutes one of the main challenges of modern society, mainly due to the lack of suitable recycling technologies, chemical recycling represents an attractive solution for the conversion of plastic solid waste into valuable chemical intermediates. Herein, a kinetic model for the pyrolysis of a dental industry waste, ethylene glycol dimethacrylate (EGDMA) crosslinked poly (methyl methacrylate) (PMMA), is presented for the first time. Kinetics parameters and their statistical significance have been estimated from eight non-isothermal thermogravimetric analysis (TGA) experiments with heating rates varying between 5 and 50 °C·min-1 by using nonlinear regression. Our analysis indicates that the mechanism of depolymerisation of EGDMA crosslinked PMMA is likely to involve a consecutive reaction pathway involving two steps. The developed kinetic model - containing five kinetic parameters only - was able to predict well all non-isothermal TGA runs, and was validated against isothermal TGA experiments at 400 °C

Anais do XXII Seminário de Formação de Professores para o MERCOSUL/ CONE SUL

1036 p. : tabs.Homenagem ao professor Augusto Nibaldo Silva TriviñosEvento realizado em Porto Alegre de 3 a 7 de novembro de 2014Apresentação: O XXII Seminário de Formação de Professores para o MERCOSUL/ CONE SUL, está concebido dentro da problemática geral do projeto intitulado “A formação de professores para o MERCOSUL/CONE SUL (Argentina, Bolívia, Brasil, Chile, Paraguai, Uruguai e Venezuela): princípios, objetivos e modalidades. Perspectivas de uma formação básica, comum, geral”, fundado em agosto de 1993, com sede na Universidade Federal do Rio Grande do Sul – UFRGS, no qual participam professores pesquisadores dos sete países mencionados. Os vinte e dois anos de existência refletidos em vida intelectual e em bases de amizade, de fraternidade, de respeito, de cooperação, de sentimentos coletivos, além do interesse individual, de Grupo, de Nação, antecipam a possibilidade de intercambiar idéias no XXII Seminário Internacional de Investigação sobre a Formação de Professores para o MERCOSUL/CONE SUL, com a temática central: Formação do Professor como Pesquisador da/para América Latina: Augusto Nibaldo Silva Triviños, a ser realizado na Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, de 03 a 07 de novembro de 2014. A realização do Seminário, organizado pelo Grupo brasileiro, permitirá projetar os possíveis próximos passos do Grupo, debater as pesquisas efetuadas, integrar os projetos sobre a Formação do Professor como Pesquisador, apresentar proposições, especialmente, para os sistemas educacionais do MERCOSUL/CONE SUL, além de divulgar e organizar, pelo menos, uma publicação em forma de livro. Os Seminários anteriores foram realizados anualmente e de modo alternado entre os países integrantes do grupo: Brasil (1993, 1994, 2002, 2006, 2009 e 2010), Chile (1995, 1998, 2003, 2005 e 2012), Argentina (1996, 2000, 2004, 2008 e 2013), Uruguai (1997, 2001 e 2011), Paraguai (1999) e Venezuela (2007). Tal Evento, para sua realização, depende do apoio das universidades nas quais os pesquisadores estão vinculados, das instituições participantes e dos organismos de fomento à pesquisa para consolidar a formação de professores e pesquisadores já realizada pelas instituições envolvidas, com possibilidade de divulgação para a sociedade brasileira, latino-americana e em particular do MERCOSUL/CONE SUL

Produção orgânica de rabanete em plantio direto sobre cobertura morta e viva.

O objetivo deste trabalho foi avaliar o uso de plantas espontâneas e cobertura viva de amendoim forrageiro(Arachis pintoi), associado à aplicação de composto orgânico na produção orgânica do rabanete em plantio direto. O experimento foi instalado na Universidade Federal do Acre, em Rio Branco-AC, de 15/06 a 14/07/2007. O delineamento experimental utilizado foi em blocos casualizados com parcelas subdivididas 4x3, em quatro repetições. As parcelas corresponderam ao sistema de plantio direto com cobertura viva de amendoim forrageiro, cobertura viva de planta espontânea, cobertura morta de planta espontânea e sistema de plantio em canteiro com solo descoberto. As subparcelas foram compostas pelas doses de composto orgânico de 5, 10 e 15 t ha-1 (base seca). O plantio direto na palha de plantas espontâneas teve desempenho semelhante ao preparo convencional do solo, ambos superiores ao plantio sobre as coberturas vivas. A produtividade do rabanete cv. Cometo, não foi afetada pelas doses crescentes de composto orgânico, podendo aplicar-se apenas 5 t ha-1, enquanto em preparo convencional do solo, o aumento da produtividade ultrapassa o plantio direto na palha apenas na dose maior de composto (15 t ha-1)

Dynamics of early establishment of SARS-CoV-2 VOC Omicron lineages in Minas Gerais, Brazil

Brazil is one of the nations most affected by Coronavirus disease 2019 (COVID-19). The introduction and establishment of new virus variants can be related to an increase in cases and fatalities. The emergence of Omicron, the most modified SARS-CoV-2 variant, caused alarm for the public health of Brazil. In this study, we examined the effects of the Omicron introduction in Minas Gerais (MG), the second-most populous state of Brazil. A total of 430 Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) samples from November 2021 to June 2022 from Belo Horizonte (BH) city were sequenced. These newly sequenced genomes comprise 72% of all previously available SARS-CoV-2 genomes for the city. Evolutionary analysis of novel viral genomes reveals that a great diversity of Omicron sublineages have circulated in BH, a pattern in-keeping with observations across Brazil more generally. Bayesian phylogeographic reconstructions indicate that this diversity is a product of a large number of international and national importations. As observed previously, São Paulo state is shown as a significant hub for viral spread throughout the country, contributing to around 70% of all viral Omicron introductions detected in MG