RESUMO
Understanding the origins of sediment transport in river systems is crucial for effective watershed management, especially after catastrophic events. This information is essential for the development of integrated strategies that guarantee water security in river basins. The present study aimed to investigate the rupture of the B1 tailings dam of the Córrego do Feijão mine, which drastically affected the Brumadinho region (Minas Gerais, Brazil). To address this issue, a confluence-based sediment fingerprinting approach was developed through the SedSAT model. Uncertainty was assessed through Monte Carlo simulations and Mean Absolute Error (MAE). Estimates of the overall average contributions of each tributary were quantified for each station and annually during the period 2019-2021. It was observed that the sampling point PT-09, closest to the dam breach, contributed to almost 80% of the Paraopeba River in 2019. Despite the dredging efforts, this percentage increased to 90% in 2020 due to the need to restore the highly degraded area. Additionally, the main tributaries contributing to sediment increase in the river are Manso River "TT-03" (almost 36%), associated with an area with a high percentage of urban land use, and Cedro stream "TT-07" (almost 71%), whose geology promotes erosion, leading to higher sediment concentration. Uncertainties arise from the limited number of available tracers, variations caused by dredging activities, and reduced data in 2020 due to the pandemic. Parameters such as land use, riparian vegetation degradation, downstream basin geology, and increased precipitation are key factors for successfully assessing tributary contributions to the Paraopeba River. The obtained results are promising for a preliminary analysis, allowing the quantification of key areas due to higher erosion and studying how this disaster affected the watershed. This information is crucial for improving decision-making, environmental governance, and the development of mitigating measures to ensure water security. This study is pioneering in evaluating this methodology in watersheds affected by environmental disasters, where restoration efforts are ongoing.
Assuntos
Monitoramento Ambiental , Colapso Estrutural , Monitoramento Ambiental/métodos , Conservação dos Recursos Naturais , Efeitos Antropogênicos , Sedimentos Geológicos , Política Ambiental , BrasilRESUMO
In Mexico, the genetic mechanisms underlying childhood obesity are poorly known. We evaluated the effect of loci, known to be associated with childhood body mass index (BMI) in Europeans, in Mexican children from different ethnic groups. We performed linear and logistic analyses of BMI and obesity, respectively, in Mestizos and Amerindians (Seris, Yaquis and Nahuatl speakers) from Northern (n = 369) and Central Mexico (n = 8545). We used linear models to understand the effect of degree of Amerindian ancestry (AMA) and genetic risk score (GRS) on BMI z-score. Northern Mexican Mestizos showed the highest overweight-obesity prevalence (47.4%), followed by Seri (36.2%) and Central Mexican (31.5%) children. Eleven loci (SEC16B/rs543874, OLFM4/rs12429545/rs9568856, FTO/rs9939609, MC4R/rs6567160, GNPDA2/rs13130484, FAIM2/rs7132908, FAM120AOS/rs944990, LMX1B/rs3829849, ADAM23/rs13387838, HOXB5/rs9299) were associated with BMI and seven (SEC16B/rs543874, OLFM4/rs12429545/rs9568856, FTO/rs9939609, MC4R/rs6567160, GNPDA2 rs13130484, LMX1B/rs3829849) were associated with obesity in Central Mexican children. One SNP was associated with obesity in Northern Mexicans and Yaquis (SEC16B/rs543874). We found higher BMI z-score at higher GRS (ß = 0.11, p = 0.2 × 10-16) and at lower AMA (ß = -0.05, p = 6.8 × 10-7). The GRS interacts with AMA to increase BMI (ß = 0.03, p = 6.08 × 10-3). High genetic BMI susceptibility increase the risk of higher BMI, including in Amerindian children.
Assuntos
Sobrepeso/genética , Obesidade Infantil/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Índice de Massa Corporal , Criança , Pré-Escolar , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Indígenas Norte-Americanos/genética , Masculino , México/epidemiologia , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , População Branca/genéticaRESUMO
Sorprende la falta de conocimientos sobre algunos aspectos elementales de la fisiología y del comportamiento sexual humano. Pocos son los que se tienen al respecto de uno, bien conocido, cual es la simulación del orgasmo en la mujer; y prácticamente ninguno al respecto de lo que ocurre en el hombre; y sorprende, más aún, que sean publicaciones aisladas de revistas populares, las que intentan algo al respecto. Por esto, y con el fin de llegar al fondo de algunos de los aspectos comportamentales mal conocidos de la respuesta sexual humana, como es la simulación del orgasmo en el hombre, es que se emprendió el presente estudio; se encuestaron 1520 hombres entre los 40 y 70 años con vida sexualmente activa; se excluyeron 25 por baja comprensión; sobre 1495 se encontró que simularon el 13 por ciento; de estos simularon una sola vez el 19 por ciento, algunas veces el 70 por ciento y frecuentemente el 11 por ciento; el 40 por ciento acudieron a la simulación por Síndrome de Eyaculación Inhibida (de diversas causas: edad, ansiedad, alcohol, 2do. coito aneyaculatorio); en el restante 60 por ciento las causas fueron en orden descendente: por temor al embarazo, por "Síndrome de Ahorro", por ir en pos del orgasmo simultáneo, los que no saben por qué, los de deficiente erección para mantener, los que lo hacían para poder repetir coito y finalmente, por anorgasmia de la compañera. En el 80 por ciento no se relató reacción negativa por parte de la compañera; no se pudo precisar con qué frecuencia la mujer percibió la simulación; se señala cómo es bien diferente la motivación de simulación en el hombre en comparación con la mujer quien a su vez presenta una frecuencia mucho mayor de simulación orgásmica que varía entre el 50 por ciento y 75 por ciento