Both cetaceans in the Brazilian Amazon show sustained, profound population declines over two decades

<div><p>Obligate river dolphins occur only in the rivers of Asia and South America, where they are increasingly subject to damaging pressures such as habitat degradation, food competition and entanglement in fishing gear as human populations expand. The Amazon basin hosts two, very different, dolphins—the boto or Amazon river dolphin (<i>Inia geoffrensis</i>) and the smaller tucuxi (<i>Sotalia fluviatilis</i>). Both species have wide geographical ranges and were once considered to be relatively abundant. Their IUCN Red List conservation status of Data Deficient (DD), due to limited information on threats, ecology, population numbers and trends, did not initially cause alarm. However, the development of dolphin hunting to provide fish bait at around the beginning of this millennium broadly coincided with the onset of a widespread perception that numbers of both species were in decline. Consequently, the need for population trend data to inform conservation advice and measures became urgent. This paper presents a 22-year time series of standardised surveys for both dolphins within the Mamirauá Reserve, Amazonas State, Brazil. Analysis of these data show that both species are in steep decline, with their populations halving every 10 years (botos) and 9 years (tucuxis) at current rates. These results are consistent with published, independent information on survival rates of botos in this area, which demonstrated a substantial drop in annual survival, commencing at around the year 2000. Mamirauá is a protected area, and is subject to fewer environmental pressures than elsewhere in the region, so there is no reason to suspect that the decline in dolphins within the Reserve is more pronounced than outside it. If South America's freshwater cetaceans are to avoid following their Asian counterparts on the path to a perilous conservation status, effective conservation measures are required immediately. Enforcement of existing fishery laws would greatly assist in achieving this.</p></div

Implementação da Linguagem Funcional SCRIPT

Este artigo mostra a compilação de programas escritos na linguagem SCRIPT para C. SCRIPT é uma linguagem funcional, ela atende a propósitos gerais e visa prover uma notação adequada para permitir que descrições de semântica denotacional possam ser processadas. Alguns fatores determinantes para a escolha da linguagem C como linguagem objeto foram: sua vasta utilização, seu poder de expressão e o fato de poderem ser encontrados v vários compiladores eficientes no mercado. O compilador foi desenvolvido pela equipe de pesquisadores do Laboratório de Linguagens de Programação da UFMG, sendo composto por três etapas: Front-End, Lambda-Lifting e Back-End. Este artigo descreve as etapas de implementação do Front-End e do Lambda-Lifting.Área: Informática Teórica - Inteligencia Artificial - Lenguajes - CompiladoresRed de Universidades con Carreras en Informática (RedUNCI

Implementação da Linguagem Funcional SCRIPT

Este artigo mostra a compilação de programas escritos na linguagem SCRIPT para C. SCRIPT é uma linguagem funcional, ela atende a propósitos gerais e visa prover uma notação adequada para permitir que descrições de semântica denotacional possam ser processadas. Alguns fatores determinantes para a escolha da linguagem C como linguagem objeto foram: sua vasta utilização, seu poder de expressão e o fato de poderem ser encontrados v vários compiladores eficientes no mercado. O compilador foi desenvolvido pela equipe de pesquisadores do Laboratório de Linguagens de Programação da UFMG, sendo composto por três etapas: Front-End, Lambda-Lifting e Back-End. Este artigo descreve as etapas de implementação do Front-End e do Lambda-Lifting.Área: Informática Teórica - Inteligencia Artificial - Lenguajes - CompiladoresRed de Universidades con Carreras en Informática (RedUNCI

Contamination analysis of Arctic ice samples as planetary field analogs and implications for future life-detection missions to Europa and Enceladus

Missions to detect extraterrestrial life are being designed to visit Europa and Enceladus in the next decades. The contact between the mission payload and the habitable subsurface of these satellites involves significant risk of forward contamination. The standardization of protocols to decontaminate ice cores from planetary field analogs of icy moons, and monitor the contamination in downstream analysis, has a direct application for developing clean approaches crucial to life detection missions in these satellites. Here we developed a comprehensive protocol that can be used to monitor and minimize the contamination of Arctic ice cores in processing and downstream analysis. We physically removed the exterior layers of ice cores to minimize bioburden from sampling. To monitor contamination, we constructed artificial controls and applied culture-dependent and culture-independent techniques such as 16S rRNA amplicon sequencing. We identified 13 bacterial contaminants, including a radioresistant species. This protocol decreases the contamination risk, provides quantitative and qualitative information about contamination agents, and allows validation of the results obtained. This study highlights the importance of decreasing and evaluating prokaryotic contamination in the processing of polar ice cores, including in their use as analogs of Europa and Enceladus.info:eu-repo/semantics/publishedVersio