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Environmental impacts caused by mining activities (mainly tailings and effluents) are presenting serious challenges for humanity worldwide. In Brazil, clay extraction activities in the Ceramic District of Santa Gertrudes (CDSG) have led to the formation of abandoned drainage wells causing environmental and human health concerns. In the 90's, it was discovered that in one of the production areas, known as the region of the lakes of Santa Gertrudes, several ceramic industries had contaminated lakes created by abandoned clay pits with industrial effluents containing toxic metals. In the present study, analysis of total and dissolved concentrations of Al, Cd, Co, Cu, Mn, Ni, Pb and Zn in the waters of these lakes were combined with the diffusive gradients in thin films (DGT) technique to assess the lability and bioavailability of the target elements, representing one of the first studies to investigate the real environmental impact of contamination caused by ceramic production wastes to an aquatic system. Furthermore, based on the total concentrations and main physicochemical characteristics of each lake, a speciation analysis was performed using the MINTEQ software which data was compared with other surface water systems. The results indicated the presence of metals associated with ceramic residues in total, dissolved and labile fractions. It was verified that Zn, Ni and Cu were the only target metals found in labile form and according to speciation were present in the form of "free" ions, and thus may present risk in terms of bioavailability, although the majority of the total concentrations are within the limits established by the national environmental agency.

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OBJECTIVE: To study the impact of transpyloric (TP) feed initiation on short-term oxygenation and manual oxygen blender titration among extremely low birth weight infants. STUDY DESIGN: This retrospective study evaluated several measures of oxygenation among extremely low birth weight infants receiving positive pressure respiratory support for 96 hours before and after TP tube placement in a single neonatal intensive care unit during the years 2017- 2020. The measures included the achieved oxygen saturation (SpO2), the baseline fraction of inspired oxygen (FiO2), the SpO2/FiO2 ratio, the number and severity of hypoxemic episodes and the frequency of manual oxygen titrations (titration index) and were analyzed using an interrupted time series regression approach. RESULTS: A total of 56 infants were evaluated. No significant differences were observed in any oxygenation measures during TP vs gastric feeding among 14 intubated infants. However, among 42 nonintubated patients, significant improvements were observed in the median SpO2/FiO2 ratios (P = .001), median titration index (P = .05), median number of hypoxemic episodes (P = .02), and median severity of hypoxemic episodes (P = .008) after TP tube placement. CONCLUSIONS: The transition from gastric to TP tube feeding was temporally associated with acute improvement in oxygenation for nonintubated infants, but not for intubated infants.

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Understanding soil organic matter (SOM) dynamics is essential to employ management that contribute to the improvement of soil quality (SQ). The aim of this study was to characterize the SOM and evaluate the emission of mineralizable C (C-CO2) in different management systems. The soil was collected in five managed areas: exposed soil (ES), conventional tillage system (CTS), no-tillage system (NTS), permanent pasture (PP) and sugarcane (SC), in addition to a forest area (NF), in the layers of 0-5, 5-10, and 10-20 cm. Total organic carbon (TOC), physical-granulometric fractionation of SOM were performed, determining the contents and stocks of particulate organic matter (C-POM; StockPOM) and mineral organic matter (C-MOM; StockMOM), in addition to calculating SQ indices. In addition to C-CO2 emissions from the soil. The areas of PP and NTS presented the highest levels of TOC in the surface layer. The highest levels of C-MOM and StockMOM were observed in the PP area, besides higher CSI (carbon stock index), reaching 1.67 in the 10-20 cm layer. The areas of PP and SC were similar to the NF in all layers regarding CMI (carbon management index). In CTS, there were higher peaks in emissions and accumulation of C-CO2. It is evident that the improvements in the SQ in the areas of PP, SC, and NTS caused mainly by the deposition of plant material and by soil revolving not being performed. In the CTS, high emission peaks of C-CO2 show that the lack of conservation management practices contributes to the emission of greenhouse gases.

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OBJECTIVE: To study characteristics of oxygenation during the first 2 postnatal months and correlation with the occurrence and severity of retinopathy of prematurity (ROP) among infants of extremely low birth weight. STUDY DESIGN: This retrospective study analyzed the incidence and severity of hyperoxemia and hypoxemia while on respiratory support with or without supplemental oxygen among infants of extremely low birth weight (birth weight <1000 g) admitted to the neonatal intensive care unit during 2016-2020. The findings were correlated with the occurrence and severity of ROP after adjusting for baseline covariates. RESULTS: After adjusting for differences in baseline demographic and clinical features, the group with severe ROP was exposed to greater fraction of inspired oxygen (FiO2) (P = .001) and experienced more frequent FiO2 titration adjustments (P = .001) compared with the group without ROP. Ambient air hyperoxemia occurred more frequently in the group without ROP (P = .003), and iatrogenic hyperoxemia occurred more frequently in the group with severe ROP (P = .046). There were no differences in the severity of ambient and iatrogenic hyperoxemia in the study population. The group with severe ROP demonstrated more hypoxemic episodes (P = .01) and longer time spent in the severe hypoxemic range (P = .005) compared with the group without ROP. CONCLUSIONS: Severe ROP is associated with greater FiO2 exposure, increased iatrogenic hyperoxemia, decreased ambient air hyperoxemia, and increased hypoxemia in infants of extremely low birth weight despite a greater frequency of FiO2 titration. This study illustrates the need for automated closed loop FiO2 delivery systems to further optimize oxygen saturation targeting in this high-risk population.

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The chemical fractionation of C by an increasing oxidation gradient, has shown to be a fast and promising methodology to detect changes in C lability. The objectives of the present study presents were: to evaluate the level of lability of soil organic C after conversion of degraded pasture into leguminous trees; evaluate the influence of soil depth on the lability of soil organic C. The experimental area consisted of pure plantations of Acacia auriculiformis, Mimosa caesalpiniifolia and Inga sp., a pasture and a secondary forest. The oxidizable organic carbon was determined by wet oxidation and allowed separation of four fractions according to the lability level (labile, moderately labile, moderately recalcitrant, recalcitrant). Labile fraction was the predominant fraction in all vegetation covers and depths. The conversion of degraded pasture into forest legume plantations and the soil depth promoted changes in the chemical composition of C. The continuous deposition of vegetable residues 13 years of leguminous trees favored the distribution of labile and moderately labile fractions along the soil profile and the recalcitrant fraction in the topsoil. The reference covers contributed to the recalcitrant fraction in the soil below 20 cm depth.

O fracionamento químico de carbono (C) por um gradiente crescente de oxidação, tem se mostrado uma metodologia rápida e promissora para detectar alterações na labilidade de C. Os objetivos do presente estudo foram: avaliar o nível de labilidade do C orgânico do solo após a conversão de pastagens degradadas em leguminosas; avaliar a influência da profundidade do solo na labilidade do C orgânico do solo. A área experimental consistiu em plantios puros de Acacia auriculiformis, Mimosa caesalpiniifolia e Inga sp., uma pastagem e uma mata secundária. O carbono orgânico oxidável foi determinado por oxidação úmida e permitiu a separação de quatro frações de acordo com o nível de labilidade (lábil, moderadamente lábil, moderadamente recalcitrante, recalcitrante). A fração lábil foi a fração predominante em todas as coberturas vegetais e profundidades. A conversão de pastagens degradadas em leguminosas florestais e a profundidade do solo promoveram mudanças na composição química do C. A deposição contínua de resíduos vegetais por 13 anos de leguminosas favoreceu a distribuição das frações lábil e moderadamente lábil ao longo do perfil do solo e da fração recalcitrante na camada superficial do solo. As coberturas de referência contribuíram para a fração recalcitrante no solo abaixo de 20 cm de profundidade.

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Mine restoration is a long and ongoing process, requiring careful management, which must be informed by site-specific, geochemical risk assessment. Paired topsoil and tree core samples from 4 sites within the uranium mining complex of INB Caldas in Minas Gerais (Brazil) were collected. Soil samples were analysed for their total content of Co, Fe, Pb, U and Zn by XRF, and subsequently, the potential environmental bioavailability of these metals were investigated by DGT and pore water analysis. In addition, results were compared with metal concentrations obtained by Tree Coring from the forest vegetation. In all sampling areas, mean total concentrations of U (Ctot. = 100.5 ± 66.5 to 129.6 ± 57.1 mg kg-1), Pb (Ctot. = 30.8 ± 12.7 to 90.8 ± 90.8 mg kg-1), Zn (Ctot. = 91.5 ± 24.7 to 99.6 ± 10.3 mg kg-1) and Co (Ctot. = 73.8 ± 25.5 to 119.7 ± 26.4 mg kg-1) in soils exceeded respective quality reference values. Study results suggest that AMD caused the increase of labile concentrations of Zn in affected soils. The high lability of the elements Pb (R = 62 ± 34 to 81 ± 29%), U (R = 57 ± 20 to 77 ± 28%) and Zn (R = 21 ± 25 to 34 ± 31%) in soils together with high bioconcentration factors found in wood samples for Pb (BCF = 0.0004 ± 0.0003 to 0.0026 ± 0.0033) and Zn (BCF = 0.012 ± 0.013 to 0.025 ± 0.021) indicated a high toxic potential of these elements to the biota in the soils of the study site. The combination of pore water and DGT analysis with Tree Coring showed to be a useful approach to specify the risk of metal polluted soils. However, the comparison of the results from DGT and Tree Coring could not predict the uptake of metals into the xylems of the sampled tree individuals.

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Mercury dynamics in hydroelectric reservoirs have been studied worldwide. In tropical reservoirs, especially in those of the Amazon, the influence of geochemistry on Hg levels along this aquatic system is not well understood. The main objective of the present study was to assess the influence of environmental conditions (physical and chemical water parameters, trace element concentrations of sediment and sediment geochemistry) on mercury levels of sediment along the Balbina Reservoir (Amazon basin, Brazil). Sediment was collected along the reservoir and in the main tributaries in May 2015 (n = 10). These samples were assessed for labile iron (LFe), manganese (LMn), aluminum (LAl) and mercury (LHg) concentrations, total mercury (THg) concentrations, organic matter (OM) content, and granulometry. Concentrations in the sediment were 4-212 (LFe), 2-460 (LAl), 180-613 (LMn), < detection limit-256 (LHg), and 12-307 µg kg-1 dry weight (THg). In general, these concentrations decreased along the reservoir from upstream to downstream, reaching the lowest concentrations in the middle of the lake, and they increased in the sampling points near the dam. The lability and concentrations of mercury were influenced by the concentrations of LFe, LMn, LAl, and the granulometry and OM content of the sediment. Altogether, THg concentrations of sediments of the Balbina Reservoir encompass the range of concentrations of other reservoirs or natural lakes in the Amazon basin (from ten to a few hundred µg kg-1 dry weight).

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Understanding why some plant lineages move from one climatic region to another is a mayor goal of evolutionary biology. In the southern Andes plant lineages that have migrated along mountain ranges tracking cold-humid climates coexist with lineages that have shifted repeatedly between warm-arid at low elevations and cold habitats at high elevations. Transitions between habitats might be facilitated by the acquisition of common traits favoring a resource-conservative strategy that copes with drought resulting from either low precipitation or extreme cold. Alternatively, transitions might be accompanied by phenotypic divergence and accelerated evolution of plant traits, which in turn may depend on the level of coordination among them. Reduced integration and evolution of traits in modules are expected to increase evolutionary rates of traits, allowing diversification in contrasting climates. To examine these hypotheses, we conducted a comparative study in the herbaceous genus Leucheria. We reconstructed ancestral habitat states using Maximum Likelihood and a previously published phylogeny. We performed a Phylogenetic Principal Components Analysis on traits, and then we tested the relationship between PC axes, habitat and climate using Phylogenetic Generalized Least Squares (PGLS). Finally, we compared the evolutionary rates of traits, and the levels of modularity among the three main Clades of Leucheria. Our results suggest that the genus originated at high elevations and later repeatedly colonized arid-semiarid shrublands and humid-forest at lower elevations. PGLS analysis suggested that transitions between habitats were accompanied by shifts in plant strategies: cold habitats at high elevations favored the evolution of traits related to a conservative-resource strategy (thicker and dissected leaves, with high mass per area, and high biomass allocation to roots), whereas warm-arid habitats at lower elevations favored traits related to an acquisitive-resource strategy. As expected, we detected higher levels of modularity in the clades that switched repeatedly between habitats, but higher modularity was not associated with accelerated rates of trait evolution.

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The Cerrado soil is under constant modification, especially because of the use of agricultural systems, which affect soil carbon (C) and phosphorus (P) functioning. Thus, the objective of this study was to determine the C and P dynamics in Brazilian Cerrado Oxisol in Piauí State under natural and anthropic conditions, considering that conservational agricultural management and no-tillage systems can restore the C and P pools in that soil. Four soil samples with distinct characteristics (native Cerrado, NC; burned native Cerrado, BNC; conventional tillage agricultural system, CTS; and no-tillage agricultural system, NTS) were collected in the study area for chemical and physical laboratory analysis. The total organic carbon (TOC) concentrations found were 33 g kg-1, 27 g kg-1, 26 g kg-1, and 20 g kg-1 for CTS, NTS, NC, and BNC, respectively. The NTS had a total nitrogen (TN) concentration of 2.0 g kg-1. The CTS had 33.4 g kg-1 of soil-oxidizable C, followed by the NTS with 27.2 g kg-1. In both studied layers, the NTS had an organic P concentration > 200 mg kg-1. The higher TOC concentration in the CTS was because of the higher content of clay in comparison with that in the NTS. The organic P in the NTS was associated with a less labile fraction of C. Thus, despite the disturbance caused by agricultural systems, the adoption of the NTS could be an influential strategy in agricultural systems to restore soil organic functioning in the Brazilian Cerrado Oxisol in Piauí State.

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Diffusive gradients in thin films technique (DGT) allows in situ determination of labile metal in water, soils, and sediments. This paper aims to evaluate the performance of a new proposal of DGT to measure Cu2+ and Cd2+ in aqueous solution using chitosan films as binding agent. These films were prepared and characterized (Fourier transform infrared spectroscopy, scanning electron microscopy, atomic force microscope, and elemental analysis). The maximum adsorption rates onto chitosan films at initial concentrations of 0.5 and 1.0 mg L-1 for Cu2+ and Cd2+ were 97%, 98% and 60%, 62%, respectively. Effects of main DGT parameters were evaluated and the results obtained suggest that the pH between 4.0 and 6.0 and ionic strength from 0.0008 to 0.1 mol L-1 presented the best ranges for the application of DGT-Chitosan. The results suggest that chitosan films prepared in this work can be an effective binding agent for DGT technique in aqueous solution. Graphical abstract.

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INTRODUCCIÓN: El trastorno por déficit de atención e hiperactividad (TDAH) es un trastorno del neurodesarrollo. Se ha documentado que existe comorbilidad importante con alteraciones en la regulación emocional, pudiendo confundirse con trastornos del estado de ánimo; el objetivo de este trabajo es actualizar la información sobre la expresión alterada de la infancia (disregulación emocional) en el TDAH. MÉTODOS: Se aplicó la estrategia PICO, se utilizaron descriptores de acuerdo al Medical Subject Headings, y se usaron bases de datos ampliamente conocidas. RESULTADOS: Fue relevante documentar que diversos autores encuentran que la asociación entre la expresión emocional anormal y el TDAH está presente, mientras que otros establecen una base neuroanatómica y neuropsicológica en esta asociación, considerando precisamente las bases en la regulación normal inherente al ser humano. CONCLUSIÓN: La disregulación emocional y el TDAH son dos trastornos que están relacionados, la evidencia es clara y sin lugar a dudas el mayor conocimiento de sus bases biológicas y psicológicas, permitirá en el futuro mejorar el pronóstico médico y la calidad de vida de los infantes. Es importante destacar que de acuerdo a la evidencia no toda problemática emocional en menores con TDAH es sinónimo de disregulación emocional.

INTRODUCTION: ADHD is a neurodevelopmental disorder. It has been documented that there is significant comorbidity with an alteration in emotional regulation, witch can be confused with mood disorders. The purpose of this work is to update the information on the altered expression of emotions in childhood (emotional dysregulation) in attention deficit and hyperactivity disorder (ADHD). METHODS: The PICO strategy was applied, descriptors were used according to the Medical Subject Headings, and well-known databases were used. Results: It was relevant to document that several authors describe an association between abnormal emotionalal expression and ADHD, while others also have a neuroanatomical and neuropsychological basis for this association. CONCLUSION: There is strong evidence for a relationship between emotional dysregulation and ADHD, understanding its biological and psychological foundations will allow for a better prognosis and quality of life. It is important to emphasize that, according to the evidence, not all emotional problems in children with ADHD are synonymous with emotional dysregulation.

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A binding phase based on the clay mineral montmorillonite (MT) was used as a sorbent in this work, which employed diffusive gradients in thin-film (DGT) devices to determine the lability of trace elements in natural waters. Montmorillonite exhibits low cost, wide availability, ease of handling, high ion-exchange capacity, and reusability. As(V), Ba2+, Cd2+, Co2+, Cr(III), Cu2+, Mn2+, Ni2+, Pb2+, Sr2+, V(V), and Zn2+ were quantitatively sorbed by MT and eluted with 1.0 mol L-1 HNO3, which provided efficiency above 70% of recovery. Validation tests were performed with synthetic solutions. The recovery of known concentrations ranged from 83 to 110%. The performance of modified DGT was compared with conventional DGT devices in experiments lasting 6 and 48 h. The results obtained with both DGT devices showed no significant differences with 95% confidence. DGT samplers with MT were deployed in the determination of labile forms of the elements in water samples from Iguaçu River (Paraná, Brazil). The measured masses of elements in MT for various durations showed good fit to a theoretical line, indicating that the results agreed with the principle of the DGT technique. The concentrations of labile species in the sample proceeded as follows; Sr > Cd > Ba > Cu > Cr > Mn > Zn > Pb. The results suggest that DGT devices with MT are an effective alternative for speciation analysis of a wide range of elements (cations as well as anions) in natural waters.

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O objetivo deste trabalho é analisar a aplicação do binômio antivitimização--autobenignidade na condição de técnica no processo de autopesquisa comvistas à autocuroterapia. Essa postura otimizadora da reciclagemintraconsciencial (recin) colabora no desenvolvimento da Inteligência Evolutiva(IE), cujo sinônimo é o autodiscernimento quanto às prioridades evolutivas.Apoiada nessas variáveis, ressalta-se que o êxito na auto-remissão dasparapatologias evolutivas depende, dentre outras auto-abordagens, da qualidadebenigna da intenção ou ortopensenidade(AU)

The objective of the article is to analyze the application of theantivictimization–self-benignity binomial as a technique of the self-researchprocess with a view to self-cure therapy. This optimizing attitude for intraconscientialrecycling contributes to the development of evolutionary intelligence(EI) the synonym of which is the self-discernment concerning evolutionarypriorities. The article, based on these variables, highlights that the success inthe self-remission of evolutionary parapathologies relies, among otherapproaches, on the benign quality of intention or orthothosenity(AU)

El objetivo de este trabajo es analizar la aplicación del binomioantivictimización-autobenignidad en la condición de técnica en el proceso deautoinvestigación con vistas a la autocuroterapia. Esa postura optimizadora delreciclaje intraconciencial (recin) colabora en el desarrollo de la InteligenciaEvolutiva (IE), cuyo sinónimo es el autodiscernimiento en cuanto a lasprioridades evolutivas. Apoyada en esas variables se resalta que el éxito en laautorremisión de las parapatologías evolutivas depende, entre otrosautoabordajes, de la calidad benigna de la intención o la ortopensenidad(AU)

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The phosphorus is retained in the soil solid phase with several degrees of energy, which depends on the characteristics and amount of the soil colloids. The no tillage system (NT) may promote phosphorus accumulation in different forms from those observed in the conventional tillage (CT) and thus, may modify the dessorption capacity of the soil. The objective of this work was to estimate the phosphorus dessorption capacity of different soils submitted to NT and CT. Samples from three soils with variable clay contents (Rhodic Hapludox - 680g kg-1 clay, Rhodic Hapludox - 530g kg-1 clay and Rhodic Paleudult - 220g kg-1 clay) cultivated under NT and CT were submitted to successive extractions with anion exchange resin (AER) and adjusted first order kinetics equations to estimate the maximum phosphorus dessorption of the soil. The dessorption by the first extraction and maximum dessorption were higher in the superficial layer of the soil under NT, comparatively to CT. Only one extraction with AER represented, on average, 38, 46 and 49% of the maximum dessorption on soils with high, medium and low clay content, respectively, while that estimated by Mehlich 1 extractor represented, for the same soils, 32, 46 and 89% of the maximum dessorption.

O fósforo é retido à fase sólida do solo com diversas energias de ligação, dependentes das características e quantidade dos colóides do solo. A adoção do sistema plantio direto (SPD) pode promover o acúmulo de fósforo em formas diferentes daquelas observadas no sistema de cultivo convencional (SCC) e, assim, modificar as características de dessorção do fósforo do solo. O objetivo deste trabalho foi avaliar a capacidade de dessorção de fósforo em solos submetidos a sistemas de cultivo. Três solos com teores variáveis de argila (Latossolo Vermelho Distroférrico - 680g kg-1 de argila, Latossolo Vermelho Distrófico - 530g kg-1 de argila e Argissolo Vermelho Distrófico - 220g kg-1 de argila) cultivados sob SPD e SCC foram submetidos a extrações sucessivas com resina trocadora de ânions (RTA) e ajustadas equações de cinética de primeira ordem para estimar a capacidade de dessorção máxima do solo. A dessorção da primeira extração e dessorção máxima de fósforo foram maiores na camada superficial do solo sob SPD, comparativamente ao SCC. Uma única extração com RTA representou, em média, 38, 46 e 49% do fósforo dessorvível para o solo muito argiloso, argiloso e arenoso, respectivamente, enquanto a estimativa pelo extrator Mehlich 1 representou, para os mesmos solos, 32, 46 e 89% da dessorção máxima de fósforo.

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The phosphorus is retained in the soil solid phase with several degrees of energy, which depends on the characteristics and amount of the soil colloids. The no tillage system (NT) may promote phosphorus accumulation in different forms from those observed in the conventional tillage (CT) and thus, may modify the dessorption capacity of the soil. The objective of this work was to estimate the phosphorus dessorption capacity of different soils submitted to NT and CT. Samples from three soils with variable clay contents (Rhodic Hapludox - 680g kg-1 clay, Rhodic Hapludox - 530g kg-1 clay and Rhodic Paleudult - 220g kg-1 clay) cultivated under NT and CT were submitted to successive extractions with anion exchange resin (AER) and adjusted first order kinetics equations to estimate the maximum phosphorus dessorption of the soil. The dessorption by the first extraction and maximum dessorption were higher in the superficial layer of the soil under NT, comparatively to CT. Only one extraction with AER represented, on average, 38, 46 and 49% of the maximum dessorption on soils with high, medium and low clay content, respectively, while that estimated by Mehlich 1 extractor represented, for the same soils, 32, 46 and 89% of the maximum dessorption.

O fósforo é retido à fase sólida do solo com diversas energias de ligação, dependentes das características e quantidade dos colóides do solo. A adoção do sistema plantio direto (SPD) pode promover o acúmulo de fósforo em formas diferentes daquelas observadas no sistema de cultivo convencional (SCC) e, assim, modificar as características de dessorção do fósforo do solo. O objetivo deste trabalho foi avaliar a capacidade de dessorção de fósforo em solos submetidos a sistemas de cultivo. Três solos com teores variáveis de argila (Latossolo Vermelho Distroférrico - 680g kg-1 de argila, Latossolo Vermelho Distrófico - 530g kg-1 de argila e Argissolo Vermelho Distrófico - 220g kg-1 de argila) cultivados sob SPD e SCC foram submetidos a extrações sucessivas com resina trocadora de ânions (RTA) e ajustadas equações de cinética de primeira ordem para estimar a capacidade de dessorção máxima do solo. A dessorção da primeira extração e dessorção máxima de fósforo foram maiores na camada superficial do solo sob SPD, comparativamente ao SCC. Uma única extração com RTA representou, em média, 38, 46 e 49% do fósforo dessorvível para o solo muito argiloso, argiloso e arenoso, respectivamente, enquanto a estimativa pelo extrator Mehlich 1 representou, para os mesmos solos, 32, 46 e 89% da dessorção máxima de fósforo.