In the present work, carbonate samples covering wall painting of four points in the same site found at Peruaçu National Park in the extreme northwest of the state of Minas Gerais, Brazil, has been investigated and dated by thermoluminescence (TL) and electron paramagnetic resonance (EPR) techniques. The EPR spectrum of the carbonate samples presented the typical six signals due to Mn ion and signals around g~2.0 due to SO and CO. The thermal stability and dose response of the EPR signals were found to be suitable for an age determination using the center due to CO. The carbonate sample exhibits TL peaks at approximately 350 °C. TL and EPR dating of the carbonate samples that covered the cave paintings gave an age of 33.13 to 48.40 ka. This series of dating data indicate that in the region about 220-250 km from the coast and extending from the State of Piaui, Bahia to Minas Gerais people lived around 50000 years ago.
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http://dx.doi.org/10.1016/j.apradiso.2019.108847 | DOI Listing |
Astrobiology
January 2025
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA.
We review the current state of understanding of Ceres as it relates to planetary protection policy for future landed missions, including for sample return, to the dwarf planet. The Dawn mission found Ceres to be an intriguing target for a mission, with evidence for the presence of regional, possibly extensive liquid at depth, and local expressions of recent and potentially ongoing activity. The Dawn mission also found a high abundance of carbon in the regolith, interpreted as a mix of carbonates and amorphous carbon, as well as locally high concentrations of organic matter.
View Article and Find Full Text PDFPLoS Med
January 2025
Division of Infectious Diseases, Department of Medicine II, Medical Centre and Faculty of Medicine, Albert-Ludwigs-University, Freiburg, Germany.
Background: Self-reported health problems following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are common and often include relatively non-specific complaints such as fatigue, exertional dyspnoea, concentration or memory disturbance and sleep problems. The long-term prognosis of such post-acute sequelae of COVID-19/post-COVID-19 syndrome (PCS) is unknown, and data finding and correlating organ dysfunction and pathology with self-reported symptoms in patients with non-recovery from PCS is scarce. We wanted to describe clinical characteristics and diagnostic findings among patients with PCS persisting for >1 year and assessed risk factors for PCS persistence versus improvement.
View Article and Find Full Text PDFUnlabelled: One of the principles of prevention and non-drug treatment of liver diseases, including hepatitis of various etiologies, is the normalization of the diet, including the use of daily diet foods with physiologically active ingredients, in particular betulin, which helps to reduce metabolic and oxidative processes within liver cells. The aim of the work was to evaluate the in vivo effect of triterpene alcohol betulin Roth isolated from the bark of birch Betula pendula Roth. added to fat-containing products (for example, mayonnaise) on the biochemical parameters of blood and the morphological structure of the liver of rats with initiated acute toxic hepatitis.
View Article and Find Full Text PDFAnalyst
January 2025
Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu Province 215123, China.
The choices of matrices and protocols for sample deposition are critical factors, which impact each other in the matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI). Previous reports on MALDI MS matrices have only compared their performances in terms of their MS signal intensities and provided optical microphotos or MALDI MS images of sample spots but typically lacked quantitative evaluation. Therefore, there is an urgent need to develop a multivariate model to evaluate the performance of different combinations of matrices and sample protocols.
View Article and Find Full Text PDFAnal Methods
January 2025
ampere - Laboratório de Plataformas Eletroquímicas - Universidade Federal de Santa Catarina, Departamento de Química, 88040-900 Florianópolis, SC, Brazil.
Terbinafine hydrochloride (TBF) is a broad-spectrum antifungal used to treat various dermatophyte infections affecting the skin, hair, and nails. Accurate, sensitive, and affordable analytical methods are crucial for quantifying this drug. In this study, we report on the use of carbon-based electrodes for the electrochemical determination of TBF in pharmaceutical samples, including raw materials and tablets.
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