Esophageal stricture assessment by esophagogram: A pictorial review of differential diagnosis

The purpose of this article is to review the most frequent conditions associated with esophageal strictures on esophagogram. The most common causes include caustic ingestion, radiation therapy, malignancy, extrinsic compression, gastroesophageal reflux disease, infectious esophagitis, systemic diseases and membranes and rings. Adequate characterization of the stricture is necessary for formulation of the best diagnostic hypothesis and can be used to distinguish between malignant and non-malignant conditions. Keywords: Esophageal diseases; esophageal stenosis; esophagus; esophageal neoplasms; esophageal achalasia; radiography; radiology; radiotherap

INTEGRATION OF GEOPHYSICAL METHODS TO DEFINE THE GEOLOGICAL INTERFACES FOR A FUTURE METRO STATION LOCATED IN BRASILIA – DF, BRAZIL

Neste trabalho foram utilizados os métodos geofísicos de eletrorresistividade e sísmica de refração rasa em uma quadra do bairro da Asa Norte em Brasília-DF, onde haverá uma futura subestação de metrô. O objetivo deste estudo é elaborar um modelo geofísico 2D da subsuperfície e observar qual a profundidade ideal para construção desta subestação de metrô. Nas aquisições dos dados de sísmica de refração foram usados geofones de 14 Hz; na eletrorresistividade utilizou-se o arranjo dipolo-dipolo. Os resultados geofísicos foram correlacionados e o modelo interpretativo obtido com base nos resultados geofísicos apresentou três camadas distintas. Observou-se uma boa correlação entre as profundidades da primeira interface obtidas com os dois métodos

Influence of impurities on the luminescence of Er3+ doped BaTiO3 nanophosphors

The influence of the presence of barium carbonate (BaCO3) phase on the luminescence properties of barium titanate nanocrystals (BaTiO3) powders was investigated. Structural and optical characterizations of erbium (Er3+) doped BaTiO3 synthesized by the sol-emulsion-gel were performed. Using Fourier transform infrared spectroscopy and X-ray powder diffraction, we identified the presence of impurities related to BaCO3 and quantified its fraction. It was observed that the presence of BaCO3 phase, even at low levels, depletes significantly the infrared-to-visible upconverted luminescence efficiency of the produced nanopowders

Influence of impurities on the luminescence of Er3+ doped BaTiO3 nanophosphors

The influence of the presence of barium carbonate (BaCO3) phase on the luminescence properties of barium titanate nanocrystals (BaTiO3) powders was investigated. Structural and optical characterizations of erbium (Er3+) doped BaTiO3 synthesized by the sol-emulsion-gel were performed. Using Fourier transform infrared spectroscopy and X-ray powder diffraction, we identified the presence of impurities related to BaCO3 and quantified its fraction. It was observed that the presence of BaCO3 phase, even at low levels, depletes significantly the infrared-to-visible upconverted luminescence efficiency of the produced nanopowders

Brazilian Flora 2020: Leveraging the power of a collaborative scientific network

International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora