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In November 2015, a catastrophic rupture of the Fundão dam in Mariana (Brazil), resulted in extensive socio-economic and environmental repercussions that persist to this day. In response, several reforestation programs were initiated to remediate the impacted regions. However, accurately assessing soil health in these areas is a complex endeavor. This study employs machine learning techniques to predict soil quality indicators that effectively differentiate between the stages of recovery in these areas. For this, a comprehensive set of soil parameters, encompassing 3 biological, 16 chemical, and 3 physical parameters, were evaluated for samples exposed to mining tailings and those unaffected, totaling 81 and 6 samples, respectively, which were evaluated over 2 years. The most robust model was the decision tree with a restriction of fewer levels to simplify the tree structure. In this model, Cation Exchange Capacity (CEC), Microbial Biomass Carbon (MBC), Base Saturation (BS), and Effective Cation Exchange Capacity (eCEC) emerged as the most pivotal factors influencing model fitting. This model achieved an accuracy score of 92% during training and 93% during testing for determining stages of recovery. The model developed in this study has the potential to revolutionize the monitoring efforts conducted by regulatory agencies in these regions. By reducing the number of parameters that necessitate evaluation, this enhanced efficiency promises to expedite recovery monitoring, simultaneously enhancing cost-effectiveness while upholding the analytical rigor of assessments.

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The Amazon is renowned worldwide for its biological significance, but it also harbors substantial mineral reserves. Among these, the ferruginous geosystems of the region are critical for iron ore extraction, accounting for 10% of Brazil's export revenue. Additionally, this region holds a significant speleological heritage with more than 1,000 caves. However, cave conservation efforts are often in conflict with land use, necessitating mediation through environmental regulations. While conservation decisions typically consider only the caves' characteristics, such an approach fails to account for the interactions among cave communities and their surrounding landscape. This poses a challenge to reserve design for cave conservation purposes. To address this issue, we assessed the predictors that influence the similarity among cave communities, suggesting the use of this parameter as a proxy for subterranean connectivity. Applying graph theory, we proposed a tool to aid in the selection of priority caves for conservation purposes. Our study involved the sampling of invertebrates in 69 iron ore caves and analyzing 28 environmental variables related to these subterranean habitats and adjacent landscape. Our analysis revealed that landscape and habitat characteristics are more important than geographical distance in determining patterns of similarity among caves. Our graph approach highlighted densely interconnected clusters based on similarity. However, specific caves stood out for harboring exclusive fauna and/or exhibiting habitat specificity, making them unique in the study area. Thus, we recommend prioritizing cave clusters for conservation, assembling both singular caves and others that influence them. It is crucial to note that protocols for the protection of subterranean biodiversity must consider measures that encompass both the caves and the surrounding landscape. Our methodology provides insights into the connectivity among caves, identifies existing groups, highlights singular (or unique) cavities that require preservation, and recognizes those influencing these unique habitats. This methodological advancement is crucial for the development of better conservation policies for the speleological heritage in areas under constant economic pressure.

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In 2015, >50 million cubic meters of Fe mining tailings were released into the Doce River basin from the Fundão dam, raising the question of its consequences on the affected ecosystems. This study aimed to establish a mineralogical-(geo)chemical association of potentially toxic elements (PTEs) from Fe mining tailings from the Fundão dam, collected seven days after the failure, through a multidisciplinary approach combining assessment of the risk to human health, environmental geochemistry, and mineralogy. Thus, eleven tailings samples were collected with the support of the Brazilian Military Police Fire Department. Granulometry, magnetic measurements, optical microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and sequential chemical extraction of PTEs analyses were performed. Contamination indexes, assessment of risk to human health, and Pearson correlation were calculated using the results of sequential chemical extraction of PTEs. The predominance of goethite in Fe oxyhydroxide concentrates from the mud indicates that the major source of hematite may not be from tailings, but from pre-existing soils and sediments, and/or preferential dissolution of hematite in deep flooded zones of the tailings column of the Fundão dam. Moreover, the high correlation of most carcinogenic PTEs with their crystallographic variables indicates that goethite is the primary source of contaminants. Goethites from Fe mining tailings showed high specific surface area and Al-substitution, and due to their greater stability and reactivity, the impacts on PTE sorption phenomena and bioavailability may be maintained for long periods. However, their lower dissolution rate, and the consequent release of heavy metals would promote greater resilience for affected ecosystems, preventing significant PTE inputs under periodic reduction conditions. More specific studies, involving the crystallographic characteristics of Fe oxyhydroxides should be developed since they may provide another critical component of this set of complex and dynamic variables that interfere with the bioavailability of metals in ecosystems.

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A Organização Mundial de Saúde estima que aproximadamente 30% das mulheres na menacme apresentam anemia ferropriva, com implicações significativas para a saúde e a qualidade de vida delas. A anemia é definida com base nos níveis de hemoglobina e pode variar em gravidade. Essa condição resulta em comprometimento da capacidade de transporte de oxigênio, exigindo mecanismos compensatórios do organismo. Além disso, pacientes que enfrentam perda sanguínea aguda e crônica e distúrbios hemorrágicos estão em risco elevado de desenvolver anemia. O Programa Patient Blood Management (PBM) surge como uma abordagem centrada no paciente, enfocando deficiência de ferro, anemia, coagulopatia e perda de sangue. O Patient Blood Management propõe a otimização da gestão do sangue do paciente, evitando transfusões desnecessárias e promovendo uma abordagem mais conservadora. Este artigo aborda a relevância da deficiência de ferro durante a gestação e a menacme, bem como as estratégias de tratamento no período pré-operatório. A suplementação de ferro, seja por via oral ou endovenosa, é fundamental para tratar a anemia ferropriva, enquanto as hemotransfusões são reservadas para casos mais graves. A abordagem sistemática da anemia é crucial para garantir melhores desfechos em cirurgias ginecológicas e no período gestacional. A suplementação de ferro, principalmente via intravenosa, surge como uma opção terapêutica eficaz e rápida, enquanto a hemotransfusão, apesar de útil em situações específicas, apresenta riscos associados que devem ser cautelosamente avaliados.

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Since the Fundão Dam rupture in Southeastern Brazil caused an enormous amount of iron ore tailing (IOT) to be discharged into the Doce River Catchment, various works have been published on the soil, water, and biota contamination by potentially hazardous trace metals. However, the objective of this study is to investigate changes in the main chemical composition and the mineral phases, which has not been studied yet. We present an analysis of sediment samples collected in the Doce River alluvial plain, before and after the disaster, as well as the tailing deposited. Granulometry, main chemical composition by X-ray fluorescence spectrometry, mineralogy by X-ray diffractometry, quantification of mineral phases using the Rietveld method, and scanning electron microscope imaging are shown. We conclude that the Fundão Dam rupture introduced fine particles into the Doce River alluvial plain, increasing the Fe and Al content in the sediments. The high Fe, Al, and Mn contents in the finer iron ore tailing fractions represent environmental risks for soil, water, and biotic chains. The IOT mineralogical components, mainly the muscovite, kaolinite, and hematite present in the finer particles can increase the sorption and desorption capacity of harmful trace metals depending on the natural or induced redox conditions, which are not always predictable and avoidable in the environment.

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The iron ore tailings released into the Rio Doce basin after the Fundão dam collapse (Brazil), suppressed a large extent of local vegetation. The use of native species and appropriate fertilization techniques, with less economic and environmental impact, must be considered in the process for the restoration of affected areas by the tailings. For this purpose, six native tree species, pioneer (Anadenanthera colubrina, Bixa orellana, and Peltophorum dubium) and secondary (Cedrela fissilis, Handroanthus impetiginosus, and Handroanthus serratifolius), were selected. We used different conditions of fertilization: (1) inorganic fertilization, (2) inoculation with arbuscular mycorrhizal fungi and plant growth-promoting rhizobacteria, (3) combined treatment (fertilizer + inoculum), to evaluate leaf nutrient concentrations, photosynthetic capacity [chlorophyll index, maximum quantum efficiency of photosystem II (Fv/Fm) and gas exchange variables], and oxidative metabolism (H2O2, MDA, and antioxidant enzymes). Inoculation resulted in higher concentrations of foliar nitrogen, especially in pioneer species. In all treatments, the secondary species exhibited iron values considered phytotoxic, but showed reduced photosynthetic capacity only when inoculated. The highest concentrations of MDA were observed in inoculated plants of both successional groups. The antioxidant system proved to be effective in preventing oxidative damage for most of the species. These results showed that the use of inoculum can be considered an ecological alternative to inorganic additives in the area affected by iron ore tailings. Despite presenting different photosynthetic and antioxidant strategies, the evaluated species demonstrated potential for use in tailings revegetation projects.

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Introducción. La Organización Mundial de la Salud (OMS) estima que más del 40% de las mujeres embarazadas a nivel mundial tienen anemia, y la mitad de estas padecen deficiencia de hierro. La prevalencia en América Latina es del 40% y en Colombia del 44.7%. Fisiológicamente en el embarazo se produce una mal llamada "anemia dilucional", existen condiciones en la embarazada que la predisponen a tener una anemia patológica. Esta última es causada principalmente por un déficit de hierro, de allí la importancia de diagnosticar a tiempo esta entidad e iniciar el manejo. La administración de hierro es la base del tratamiento de la anemia por deficiencia de hierro. Puede ser administrado por vía oral, la cual es la preferida en la mayoría de las pacientes; sin embargo, cuando este no es posible administrarlo, es esencial recurrir al hierro parenteral. No obstante, el hierro parenteral es poco usado como primera línea en el manejo de la anemia gestacional. El presente artículo tiene como objetivo realizar una revisión que permita identificar la terapia con hierro parenteral como una alternativa eficaz de manejo para la anemia gestacional, teniendo en cuenta las características farmacológicas, la administración y el uso entre las diferentes moléculas disponibles en Colombia. Metodología. Corresponde a un estudio de revisión de literatura en bases de datos y bibliotecas electrónicas, los criterios que se tuvieron en cuenta fueron textos publicados entre 1996 y 2020, en español e inglés. Se obtuvo un resultado de 95 artículos, de los cuales se seleccionaron 49. Las palabras clave para su búsqueda fueron fisiología, hierro parenteral, anemia gestacional, déficit de hierro, complicaciones del embarazo, compuestos de hierro, farmacocinética, diagnóstico y tratamiento. División de temas tratados. Fisiología; ayudas diagnósticas; características farmacológicas del hierro parenteral; ventajas, indicaciones y contraindicaciones del hierro parenteral; efectos secundarios y forma de aplicación. Conclusiones. El hierro parenteral es un tratamiento seguro y eficaz para manejar la anemia en el embarazo, se debe tener en cuenta las indicaciones y la farmacología de las moléculas para elegir la más adecuada. Además, repone más rápidamente las reservas de hierro y los niveles de hemoglobina.

Introduction. The World Health Organization (WHO) estimates that more than 40% of pregnant women worldwide have anemia, and that half of them suffer from iron deficiency. The prevalence of this in Latin America is 40%, and in Colombia, 44.7%. Physiologically, a problem called "dilutional anemia" occurs during pregnancy. There are conditions in pregnant women that predispose them to suffering from pathological anemia. The latter is mainly caused by iron deficiency, hence the importance of diagnosing this entity on time and starting treatment. Iron administration is the basis of treatment of anemia caused by iron deficiency. It can be administered orally, which is the preferred option in the majority of patients. However, when this is not possible, parenteral iron must be used. However, parenteral iron is rarely used as the first line of treatment of gestational anemia. The objective of this article is to carry out a review that allows for the identification of therapy with parenteral iron as an efficient alternative for the treatment for gestational anemia, considering the pharmacological characteristics, administration, and use among the different molecules available in Colombia. Methodology. We carried out a search in databases and electronic libraries. The criteria considered were texts published between 1996 and 2020 in Spanish and English. 95 articles were obtained, of which 49 were selected. The keywords for their search were physiology, parenteral iron, gestational anemia, iron deficit, pregnancy complications, iron compounds, pharmacokinetics, diagnosis, and treatment. Division of Covered Topics. Physiology; diagnostic aids; pharmacological characteristics of parenteral iron; advantages, indications, and contraindications of parenteral iron; secondary effects and application method. Conclusions. Parenteral iron is a safe and efficient treatment to handle anemia during pregnancy. The indications and pharmacology of the molecules must be considered to choose the most appropriate option. In addition, it replaces iron reserves and hemoglobin levels more quickly.

Introdução. A Organização Mundial de Saúde (OMS) estima que mais de 40% das mulheres grávidas em todo o mundo são anêmicas, e metade delas sofre de deficiência de ferro. A prevalência na América Latina é de 40% e na Colômbia de 44.7%. Fisiologicamente na gravidez ocorre a chamada "anemia dilucional", e existem condições na gestante que a predispõem a ter uma anemia patológica. Esta última é causada principalmente por deficiência de ferro, daí a importância de diagnosticar esta entidade a tempo e iniciar o manejo. A administração de ferro é a base do tratamento da anemia por deficiência de ferro. Pode ser administrado por via oral, o que é preferido pela maioria das pacientes; porém, quando não for possível administrá-lo dessa forma, é imprescindível recorrer ao ferro parenteral. No entanto, o ferro parenteral é raramente usado como primeira linha no manejo da anemia gestacional. O objetivo deste artigo é realizar uma revisão que permita identificar a terapia com ferro parenteral como uma alternativa eficaz de tratamento da anemia gestacional, levando em consideração as características farmacológicas, administração e uso entre as diferentes moléculas disponíveis na Colômbia. Metodologia. Foi realizada uma busca em bases de dados e bibliotecas eletrônicas, os critérios levados em consideração foram textos publicados entre 1996 e 2020, em espanhol e inglês. Foi obtido um total de 95 artigos, dos quais 49 foram selecionados. As palavras-chave para a busca foram fisiologia, ferro parenteral, anemia gestacional, deficiência de ferro, complicações na gravidez, compostos de ferro, farmacocinética, diagnóstico e tratamento. Divisão dos temas abordados. Fisiologia; auxiliares de diagnóstico; características farmacológicas do ferro parenteral; vantagens, indicações e contraindicações do ferro parenteral; efeitos colaterais e método de aplicação. Conclusões. O ferro parenteral é um tratamento seguro e eficaz para o manejo da anemia na gravidez, as indicações e farmacologia das moléculas devem ser levadas em consideração a fim de escolher a mais adequada. Além disso, reabastece mais rapidamente as reservas de ferro e os níveis de hemoglobina.

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Studying the adsorption-desorption kinetics of ions and molecules is crucial to understand the mobility of nutrients and pollutants in the environment. This article reports the adsorption-desorption kinetics of phosphate on goethite, as measured by ATR-FTIR spectroscopy at pH 4.5, 7.0 and 9.5. The system phosphate-goethite has become a model system to test new experimental setups and theories to understand the behavior of pollutants with phosphonic or phosphinic moieties such as glyphosate or glufosinate. One of the main difficulties in the analysis of ATR-FTIR spectra in adsorption-desorption kinetics is to calibrate the equipment to convert absorbance vs. t curves into adsorption vs. t curves, and thus the methodology to achieve a good calibration using spectroscopic data in combination with adsorption isotherms is clearly described. The time evolution of the different surface species was monitored simultaneously during adsorption and desorption at different pH, showing the advantages of this spectroscopy over traditional adsorption methods that only quantify total adsorption. Results were analysed in terms of a simple adsorption-desorption model that takes into account transport, attachment, detachment and surface transformation of the adsorbed species. The same rate parameters at a given pH could predict well the adsorption-desorption kinetics of the two formed surface species and the corresponding adsorption isotherm, giving new insights into the dynamics of phosphate on the surface of goethite. It was found that phosphate desorbed faster from goethite at low pH than at high pH, which is counterintuitive, but has good practical and environmental applications.

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