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Pesticides are released into the environment daily, and their effects on nontarget species in aquatic ecosystems have been widely reported. To evaluate the adverse effects caused in adults of Danio rerio species exposed to the pesticides abamectin, difenoconazole, and their commercial formulations (Kraft 36EC® and Score 250EC®), both isolated and in mixtures, biochemical biomarkers were analyzed in the gills of organisms exposed to sublethal concentrations. To this end, the activities of the enzymes 7-ethoxyresorufin-O-deethylase (EROD), glucuronosyltransferase (UDPGT), glutathione-S-transferase (GST), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), lipid hydroperoxide (LH), and malondialdehyde (MDA), which are indicative of oxidative stress, were measured after 48 h of exposure to the different pesticide treatments. The results showed a significant increase in EROD activity and MDA levels in the gills of fish exposed to the commercial formulation of abamectin. When the fish were exposed to difenoconazole and its commercial formulation, an increase in GST, GPx, and MDA levels and a decrease in GR activity were observed in the gills. Furthermore, the responses of the biomarkers were more pronounced in organisms exposed to mixtures of both active ingredients and commercial formulations. It is concluded that the commercial formulations Kraft 36EC® and Score 250EC® and their mixtures cause significant alterations in the detoxification metabolism of exposed organisms and induce oxidative stress in fish., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ana Leticia Madeira Sanches reports financial support was provided by State of Sao Paulo Research Foundation. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Human intelligence has always been a fascinating subject for scientists. Since the inception of Spearman's general intelligence in the early 1900s, there has been significant progress towards characterizing different aspects of intelligence and its relationship with structural and functional features of the brain. In recent years, the invention of sophisticated brain imaging devices using Diffusion-Weighted Imaging (DWI) and functional Magnetic Resonance Imaging (fMRI) has allowed researchers to test hypotheses about neural correlates of intelligence in humans.This review summarizes recent findings on the associations of human intelligence with neuroimaging data. To this end, first, we review the literature that has related brain morphometry to intelligence. Next, we elaborate on the applications of DWI and restingstate fMRI on the investigation of intelligence. Then, we provide a survey of literature that has used multimodal DWI-fMRI to shed light on intelligence. Finally, we discuss the state-of-the-art of individualized prediction of intelligence from neuroimaging data and point out future strategies. Future studies hold promising outcomes for machine learning-based predictive frameworks using neuroimaging features to estimate human intelligence., Competing Interests: Conflict of interest The authors declared no conflict of interest., (Copyright© 2021 Iranian Neuroscience Society.)

Normal aging incurs functional and anatomical alterations in the brain. Cortical thinning, age-related alterations in resting-state functional connectivity (RSFC) and reductions in fractional amplitude of low frequency fluctuations (fALFF) are key components of brain aging that can be studied by neuroimaging. However, the level of association between these processes has not been fully established. We performed an analysis at multiple-levels, i.e. region or connection and modality, to investigate whether the evidence for the effect of aging on fALFF, RSFC and cortical thickness are associated in a large cohort. Our results show that there is a positive association between the level of evidence of age-related effects in all three in the brain. We also demonstrate that on a regional basis the association between RSFC alterations and cortical atrophy may be either positive or negative, which may relate to compensatory mechanisms predicted by the Scaffolding Theory of Aging and Cognition (STAC)., Competing Interests: Declaration of competing interest Authors declare that there is no conflict of interest., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Concerns have been raised in recent years on the potential risks related with pesticide mixtures that are likely to be present in agricultural edge-of-field waterbodies. Despite the high use of pesticides in tropical countries like Brazil, studies evaluating pesticide mixtures are especially scarce in the tropics. The insecticide abamectin and the fungicide difenoconazole are the main pesticides intensively used in Brazilian strawberry crop and are hence likely to occur simultaneously. The aim of the present study was therefore to evaluate the toxicity of abamectin, difenoconazole and their mixture to the tropical fish Danio rerio. Laboratory toxicity tests with the individual pesticides indicated 48 h-LC 50 values of 59 μg L -1 for abamectin and 1.4 mg L -1 for difenoconazole. Mixtures of the two pesticides revealed a synergistic deviation of the independent action model. Implications of study findings for the aquatic risk assessment of pesticide mixtures, especially in tropical countries and indications for future research are discussed., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Aquatic risk assessments of pesticides in tropical countries have often been disputed for being largely based on risk evaluations conducted in temperate regions. Although pesticide sensitivity comparisons between temperate and tropical freshwater organisms have indeed not revealed consistent differences, risk assessments are currently still based on a relatively small tropical toxicity dataset. In addition, greater levels of runoff and spray drift may be expected in tropical than in temperate agroecosystems, indicating that aquatic life in edge-of-field water bodies is likely to be subjected to higher concentrations of pesticides and their mixtures. The aim of the present study was to evaluate the toxicity of Kraft ® 36 EC (a.i. abamectin), Score ® 250 EC (a.i. difenoconazole) and their mixture to the Neotropical cladoceran Macrothrix flabelligera. Laboratory toxicity tests with the individual formulated products indicated EC50-48h values of 3.1 and 659μg a.i./L given as nominal test concentrations, respectively. Mixtures of the two pesticides revealed a concentration-dependent deviation of the independent action model, with antagonism at low and synergism at high pesticide mixture concentrations. Laboratory toxicity tests were also conducted with microcosm water that was treated with the individual or mixtures through runoff or direct overspray. Microcosm tanks receiving runoff water from experimental soil plots applied with recommended doses of the individual pesticides did not show toxicity to the test organism. Microcosms that received runoff water containing the pesticide mixture, however, did cause a short-term effect on immobility. The microcosms that were treated by direct overspray of both pesticide formulations showed the most pronounced toxic effects. Study findings suggest a potential risk of these pesticides at environmentally relevant concentrations, especially when they are both present., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Edge-of-field waterbodies in tropical agroecosystems have been reported to be especially prone to pesticide contamination through runoff resulting from intensive irrigation practices and tropical rainfall. In the present study, the effects of runoff from an experimental agricultural field applied with Vertimec(®) 18EC (active ingredient: abamectin) on zebrafish were evaluated. To this end, the experimental field was applied with the Vertimec(®) 18EC dose recommended for strawberry crop in Brazil, whereas another field was treated with water only to serve as control. No effects of runoff water from either plot were recorded on survival. Water from the treated field led to increased growth and gill alterations. In general, these alterations were of the first and second degree, including proliferation of cells between the secondary lamellae, dilation at the lamellar apex, detachment of the respiratory epithelium and aneurism. These results confirm the high toxic potential of Vertimec(®) 18EC and provide evidence that environmental risks are likely to occur in areas subject to runoff containing this pesticide., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The present study aimed to evaluate the interactions of the pesticide Vertimec(®) 18EC in aquatic ecosystems. In this respect, soil plots were contaminated with Vertimec(®) 18EC at the concentration indicated for strawberry crops (0.125L of solution m(-2)). After the contamination, torrential rainfall was simulated and the surface runoff was collected and transferred to mesocosm tanks in five treatments, run in triplicate: (1) control-C; (2) runoff from an uncontaminated plot-UR; (3) runoff from the plot contaminated with Vertimec(®) 18EC-CR; (4) direct application of Vertimec(®) 18EC in the water-V and (5) water samples gathered randomly to verify whether there was contamination between the mesocosms-RS. Water samples from these tanks were also submitted to ecotoxicological tests with Daphnia similis and analyses to evaluate the limnological characteristics, in five collection periods over 10 days (240h). Physical and chemical differences were observed in the water samples, mainly related to increased turbidity, suspended solids and nutrients (nitrogen and phosphate forms). Acute toxicity was observed for the direct application treatment for the entire experimental period, and in some periods for the CR treatment (from 48h to 168h). The results obtained suggest that the pesticide did not fully degrade during the study period (10 days) in the direct application treatment, demonstrating that the presence of other substances in the commercial formulation contribute to the maintenance of toxicity. This represents a potential risk for aquatic ecosystems in areas adjacent to where the chemical is applied., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Abamectin is used as an acaricide and insecticide for fruits, vegetables and ornamental plants, as well as a parasiticide for animals. One of the major problems of applying pesticides to crops is the likelihood of contaminating aquatic ecosystems by drift or runoff. Therefore, toxicity tests in the laboratory are important tools to predict the effects of chemical substances in aquatic ecosystems. The aim of this study was to assess the potential hazards of abamectin to the freshwater biota and consequently the possible losses of ecological services in contaminated water bodies. For this purpose, we identified the toxicity of abamectin on daphnids, insects and fish. Abamectin was highly toxic, with an EC(50) 48 h for Daphnia similis of 5.1 ng L(-1), LC(50) 96 h for Chironomus xanthus of 2.67 μg L(-1) and LC(50) 48 h for Danio rerio of 33 μg L(-1)., (Copyright © 2011 Elsevier Ltd. All rights reserved.)