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This study investigated the sediment geochemistry of a fish farming area in net cage tanks in the Rosário reservoir, Brazil. Three areas were investigated: reference (RA), fish farming (FFA), and dispersion (DA). The results were analyzed through correlation, similarity, principal component analysis, comparison with legislation, sediment quality guidelines, and sediment pollution indices. The mean concentrations for RA, FFA, and DA areas were respectively: Cu (mg.kg-1) 37.74, 62.23, and 71.83; Mn (mg.kg-1) 22.55, 66.48, and 55.90; Zn (mg.kg-1) 9.13, 114.83, and 94.27; Fe (%) 0.28, 0.40, and 0.43; OM (%) 15.84, 21.95, and 18.45; TOC (%) 1.86, 3.69, and 6.05; TN (mg.kg-1) 2365.00, 5015.00, and 3447.51; TP (mg.kg-1) 780.00, 6896.00, and 2585.50; ORP (mV) -95.50, -135.20, and -127.10; pH 6.60, 6.58, and 6.05; <63 µm 90.59, 78.68, and 87.30. Statistically, the influence of fish farming on sediment, organic matter, and pollutant sedimentation was demonstrated. Cu and Zn concentrations were below sediment quality guidelines. Regarding legal limits (resolution 454/2012/CONAMA), nutrients in the FFA area exceeded by 60% (TN) and 100% (TP), while in DA and RA areas they were 100% lower. TOC was 100% lower in all areas. Organic matter exceeded the limit by 100% in all areas. Pollution indices resulted in: low contamination factor 78%; unpolluted for 87% of pollution load and 83% of combined pollution; moderately polluted for 75% of the Nemerow index. The greatest impacts and influence of farming on pollutant sedimentation were more concentrated in the fish farming area. In terms of legal aspects and pollution indices, fish farming produced low levels of trace metal pollution and nutrient concentrations exceeded legal limits.

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The use of pesticides is intense in agriculture and has caused contamination in water, air and soil. This fact led to the need to study strategies that can minimize the effects that these pesticides have caused to the environment. In this context, biochar appears, as a type of material that has the ability to remove chemical substances, and because they can be activated with different chemical agents, they are extremely effective in the adsorption of toxic substances. Therefore, the aim of the study was to evaluate the use of biochar as a bioadsorbent for pesticides. This is a systematic review with meta-analysis and meta-regression, as the PRISMA protocol recommendations. Studies from the last 20 years were included, with at least the abstract available and considering preferentially experimental studies. Qualitative studies or studies with high risk of bias, other reviews and duplicates were excluded. The variables analyzed were the presence of factors that prove the effectiveness or not of pesticide adsorption. Studies with a superficial approach or those that do not show positivity or negativity in relation to the outcome were excluded. The search was conducted on the sources: Scopus, Web of Science electronic databases, PubMed (of the US National Library of Medicine, National Institutes of Health) and ScienceDirect (Elsevier). For better investigative determination, the data were searched separately. The descriptors used for the search were the following: Agrochemicals AND Activated Carbon AND Adsorption. Initially, 2431 references were found, from which 14 were selected to compose the meta-analysis review. With the joint analysis of the data, it was possible to verify using the random model (since the studies assess different contexts) that there is a proportion of effectiveness of the intervention of 81% (with a 95% confidence interval), ranging from 75 to 88%, which is represented by the meta-analysis diamond that is the final result of the statistical analysis. Biochar is effective in removing impurities, even including features such as low cost. There is a considerable lack of studies on the topic of pesticide adsorption with the use of biochar. The studies approach a very heterogeneous perspective on the subject, exposing different contexts.

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High phosphate concentrations in natural waters are associated with eutrophication problems that negatively affect the fauna and flora of ecosystems. As an alternative solution to this problem, we evaluated the adsorptive capacity of the fruit peel ash (PPA) of Caryocar coriaceum Wittm and its efficiency in removing phosphate (PO43-) from aqueous solutions. PPA was produced under an oxidative atmosphere and calcinated at 500 °C. The XRF and EDS analyses of PPA after contact with an aqueous PO43- solution showed an increase in its PO43- content, thus confirming the adsorption of PO43-. The Elovich and Langmuir models are the ones fitting the kinetics and the equilibrium state of the process, respectively. The highest PO43- adsorption capacity was approximately 79.50 mg g-1 at 10 °C. PO43- adsorption by PPA is a spontaneous, favorable, and endothermic process involving structural changes. The highest removal efficiency was 97.08% using a 100 mg.L-1 PO43- solution. In sight of this, PPA has shown potential as an excellent natural bioadsorbent.

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Anthropogenic pollution by trace metals in aquatic environments in semiarid zones is a critical area of investigation. The objective of this study was to investigate the concentration and spatial distribution of trace metals in surface sediments in the Rosário reservoir, which is affected by the intensive aquaculture of Tilápia-do-Nilo (Oreochromis niloticus). Sediment samples were collected in three different areas, postculture (PCTV), cultivation (CTV) and control (CTRL) in the dry season in 2019. The granulometric composition, organic matter and concentrations of Fe, Mn, Zn, Cu, Cr, Cd, Pb and Ni metals were determined. Multivariate statistics were used. Geochemical and ecotoxicological indices and a comparison with sediment quality guidelines (SQG) were used. The sediment was characterized by silty clay loam with an average organic matter of 18.76 ± 4.27. The analytical merit figures demonstrated accuracy (metal recoveries in certified standards) between 89 to 99% and high precision (RSD < 5%). The concentration ranges for the metals were Fe: 0.11-0.85 (%), Mn: 14.46-86.91, Zn: 2.6-220.56, Cu: 26.89-98.75, Cr: 60.18-76.06, Cd: 0.38-0.59, Pb: 18.13-43.13, and Ni: 34.4-46.75, all in (mg/kg-1). The highest concentration values were found in the CTV areas (Fe: 40 ± 0.22, Mn: 66.48 ± 19.11, Zn: 114.83 ± 59.75 and Cr: 70.85 ± 2.62) and PCTV (Cd: 0.53 ± 0.04, Cu: 71.83 ± 21.20, Pb: 33.71 ± 4.34 and Ni: 44.60 ± 1.79). Pearson's correlation, hierarchical cluster analysis and principal component analysis confirmed the influence of fish farming on metals. Only Ni presented concentration values higher than the reference value established in the SQG. Thus, considering the probable geochemical and ecotoxicological effects, they comprise the two lowest levels of impact.

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In this study, five types of modified Ziziphus joazeiro barks were investigated for the removal of Pb(II) ions from aqueous solutions. The samples tested were natural barks, natural powder, washed with water, ethanol at 80% (EE) and 0.5 N NaOH. Batch kinetics experiments were performed under the conditions: 24−25 °C, pH 5.5−5.8, 102 mg·L−1 Pb(NO3)2, 100 rpm and 0.1 g of adsorbent, and analyses of pHpzc and Fourier transform infrared spectroscopy. All adsorbents tested showed potential to remove Pb(II) ions, but the adsorbent washed by 0.5 N NaOH obtained the highest experimental performance (25.5 mg·g−1 at 30 min), while the EE had the least performance (20.4 mg·g−1 at 60 min), and maximum removals of 99.9%. The kinetic models pointed to a probable chemisorption due to the best fit of pseudo-second order and Elovich, and Boyd's model, suggesting that intraparticle diffusion limits the adsorption until the initial minutes of contact. The Langmuir isotherm fitted better to the experimental data for the NaOH adsorbent, with maximum adsorption capacity equal to 62.5 mg·g−1, although the Temkin model partially fitted, both suggesting the occurrence of chemisorption. The adsorption process is reversible (>81% at 20 min) and hence the adsorbents can be recycled and the Pb(II) ions recovered.

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The eligible articles were obtained from databases such as ScienceDirect, SciELO, PubMed and Springer. The searches were performed using the terms "honey", "vitamins", "fluorescence" and their combinations. The titles and abstracts of the articles found were read and revised to verify their relevance to the review. From the selected titles, it was possible to elaborate the systematic review, based on scientific studies and sources considered faithful and true. The systematic review presented confirms the necessity for studies to identify compounds using fluorescence techniques, using cheaper and more accessible techniques. Few studies are covered in this theme, when treated about Apis mellifera honey, and it has been observed that in the last 12 years, the few researches have only tried to show the viability of using the technique without quantifying the present compounds, while others demonstrate the fluorescent aspects, but performing through techniques considered more expensive.

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This research aimed to study the validation of a viable and low-cost spectrofluorimetric method, capable of detecting and quantifying B vitamins in floral varieties of bee honey. The analyzes were performed using chemical and operational methods of pre-defined solutions and standards, performed in triplicate and the results expressed as mean ± standard deviation. The data were recorded in a Microsoft Office Excel spreadsheet (version 2013) and studied using the statistical program Bioestatic version 3.0. The calibration curves of the vitamins showed the linearity and precision of the method. Subsequently, a descriptive analysis of the data was performed, being considered normal in the Lilliefors normality tests. Finally, the data were subjected to Pearson's correlation test, showing positive and strong correlations, with r (Pearson) ranging from 0.7619 to 1. Honey had positive results regarding the detection and quantification of vitamins B1 and B2 through the spectrofluorimetric method.

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The contamination of bodies of water by potentially hazardous elements has in recent decades become an environmental problem that poses serious risks to humans, fauna, flora and microbiota, compromising the quality of life of the present ecosystem. Therefore, effluents must be properly treated in a legally acceptable manner before their disposal in the environment. With this in mind, adsorption presents itself as an inexpensive efficient technique for the removal of potentially hazardous elements from effluents with excellent adsorption capacities when natural adsorbents are used. In this study, fava d'anta fodder was used in its crude and alkalinized form to remove Cu(II) and Pb(II) ions. Equilibrium studies were carried out using adsorption isotherms in batch systems with mono- and multi-elementary systems containing the two ions. The Langmuir and Freundlich models were applied to the isotherm studies, with the ions being better suited to the Langmuir model, with maximum adsorption capacities of 24.45 mg g-1 and 68.49 mg g-1 (crude form) and 11.12 mg g-1 and 35.34 mg g-1 (alkalinized form) in the mono-elementary system for Cu(II) and Pb(II) ions, respectively.

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Human activities, especially in industry, have contributed to soil contamination with heavy or toxic metals. The objective of this study was to determine the chelating effect and antioxidant activity of pyrogallol, as well as to evaluate its cytoprotective activity in prokaryotic and eukaryotic models, animal and plant, respectively, against toxic mercury chloride action. Antioxidant activity was determined by DPPH where pyrogallol showed considerable action, chelating even iron ions. For the microbiologic activity assays, microdilution was performed to obtain the minimal inhibitory concentration, minimum bactericidal and minimum fungicide concentration, from which the sub-inhibitory concentrations were determined. The product did not conferred cytoprotection to the tested bacteria and fungi. To evaluate plant cytoprotection, Lactuta sativa seeds were used together with the product at a sub-allelopathic concentration with different HgCl2 concentrations. In this case, the tannin conferred cytoprotection to the plant model, allowing the best growth and development of caulicles and radicles, thus preserving tissues necessary for plant survival. From the results, it is observable that pyrogallol possesses cytoprotective action in the eukaryotic plant model, this action being useful as an alternative which favors the growth of plants in contaminated areas, as the recovering of crop fields or reforestation projects.

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The aim of this paper is to statistically validate the analytical curves of a chromatography method to identify and quantify azoxystrobin, difenoconazole and propiconazole residues in banana pulp, using QuEChERS and GC-SQ/MS. A matrix-matched calibration was used and analytical curves were estimated by weighted least squares regression (WLS), confirming heteroscedasticity for all compounds. Statistical tests were performed to confirm the quality adjustment of the proposed linear model. The correlation coefficient for azoxystrobin, difenoconazole and propiconazole were, respectively, 0.9985, 0.9966 and 0.9997 (concentration range: 0.05 and 2.0 mg kg-1). The limits of detection and quantification were, respectively, between 0.007 and 0.066 mg kg-1, and between 0.022 and 0.199 mg kg-1, below the maximum limits stipulated by Brazilian, American, and European legislation. Only difenoconazole had an insignificant matrix effect (6.8%). Thus, the weighted least squares method is shown to be a safe linear regression model, providing greater reliability of the results.

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The improper disposal of waste containing toxic metals promotes serious environmental problems. Biosorption stands out as a powerful technique in removing toxic metals from aqueous solutions, making it an efficient and low-cost technique, since it makes use of abundant materials and of natural origins. This work aimed to study the application of the bark of Caryocar coriaceum Wittm, as a possible bioabsorbent for the removal of Lead (II) present in aqueous solutions, for this, residues of this material were collected in a public market, where they were washed and dried, then crushed, sieved (32mesh) and washed again, to then be used in the kinetic, isotherm and thermodynamic tests of lead (II) ions adsorption. After the experiments, it was found that the increase of the temperature disfavored the rate of lead (II) adsorption, ranging from 15.6 to 13.5 mg.L-1, for temperatures of 5 °C and 35 °C, respectively. The pseudo-second order kinetic model best characterizes the adsorption velocity obtaining a linear regression coefficient of 0.9997, while the pseudo-first order obtained a value of 0.7117. Adsorption occurred by chemisorption, with intra-film diffusion. The isothermal model that best represented the adsorption was Langmuir's (R2 0.99). It was concluded that the bark of Caryocar coriaceum Wittm is a good alternative to be used as a bioabsorbent for solutions containing dissolved lead (II).

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Pesticides are part of a large group of organic compounds with different physicochemical characteristics, designed to control and prevent pests in various crops and plantations, improving productivity. This works provides a perspective on pesticide use in current agriculture with the aim of identifying the influence of pesticides on food production and their impact on the environment. Therefore, it is necessary to highlight the importance of determining pesticide residues in food, aiming to ensure food safety, since these compounds can represent risks to human health and the environment. The effects of pesticides on humans range from headaches, nausea and skin and eye irritation to chronic problems such as cancer and neurological disorders, and extend to other non-target organisms such as birds, fish and bees, contaminating water, soil, and plants, as opposed to the benefits of increased production, consequently other measures for pesticide consumption need to be evaluate to ensure human health, food safety and environmental protection. It is important to note that chromatographic techniques and mass spectrometry assist in the determination of pesticide residues and evaluate the quality of the food that reaches the consumer, and together with the Maximum Residue Limits (MRLs), established by the legislation of each country, these instrumentation act to control the exposure of population to pesticides. Although the MRL is used as a parameter for food quality, the global differences in pesticide legislation do not guarantee the consumer safety. In this sense, a brief analysis of MRL inefficiency is also present in this paper.

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In recent decades, aquatic environment pollution has become a global challenge due to a rapid industrial growth. In this context, adsorption has become one of the most used methods, gaining importance especially in the last decades, given the growing concern over environmental damages caused by these pollutants. Additionally, its low cost and bioavailability are attractive. Therefore, the present study proposed to investigate the adsorption potential of A. indica seeds for Cu(II) and Pb(II) removal in synthetic solutions. Equilibrium studies were carried out via isothermal adsorption in batch systems. Kinetic studies were used to evaluate the lowest equilibrium time. The two evaluated ions were better suited to the Langmuir model and Freundlich model. When applying Langmuir's model on Neem seed powder adsorption, maximum adsorption capacities of 11.54 mg g-1 and 17.96 mg g-1, in the crude form and 11.41 mg g-1 and 19.80 mg g-1 in the alkaline form were obtained for Cu(II) and Pb(II) ions, respectively. The equilibrium time was approximately 80 and 100 min for both ions. The kinetic model best adjusted to the phenomena was the pseudo-second order (Ho Model), suggesting adsorption mainly has a chemical nature for both the studied metals. The results showed Neem seed powder may be a sustainable, efficient and low cost alternative for the removal of Cu(II) and Pb(II) metal cations present in effluents.

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INTRODUCTION: Pesticides are organic compounds widely used in modern agriculture, being relevant for helping plantations and increasing food production. The banana, a fruit with oriental origin, stands out for being widely produced in tropical and subtropical regions which, like other matrices, is susceptible to pest action. This review aims to evaluate the presence of pesticides in bananas according to Brazilian, European and Codex legislation. METHODS: Four databases, ScienceDirect, SciELO, PubMed and Springer, were used to find relevant articles in the literature addressing methods for the determination of pesticide residues in bananas using the terms "banana", "chromatography", "pesticides" and "determination". The search stages included reading abstracts and titles, reading the full text, extracting data and analyzing data from eligible articles. The search was restricted to original research articles published in English from 2008 to 2018. RESULTS: 404 articles were found from the initial research, with only 15 studies being considered eligible for this review. Mass spectrometry is the most widely used detection technique. 5 articles were seen to use a multiresidue method to analyze only bananas (pulp), and from these, only 2 studies used methods to analyze the pulp and peel. The articles analyzed 172 samples, with 59.3% of these being conducted in Europe, 32.5% being conducted in Asia and only 8.1% in South America. A total of 79.1%, 32.4% and 42.6% of samples were unsatisfactory according to the Brazilian, European and Codex legislation, respectively, with these samples being contaminated with pesticide residues. CONCLUSION: This review presents the scarcity of articles aimed at identifying pesticide residues in bananas and the urgency of checking the quality of the fruit that reaches the population. The MRLs allowed by different legislations have clear divergences that do not ensure the lowest concentration values that guarantee consumer safety.

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Malpighia glabra L. is indicated for the treatment of diseases due presenting several medicinal properties. The aim of the present study was quantify phenolic compounds and carotenoids, additionally, evaluate the antioxidant potential of different methanolic fractions (mature stage, intermediate stage and green maturity stage) of Malpighia glabra. Methanolic fractions of the three stages of maturation were characterized using HPLC-DAD. The antioxidant activity of fractions was evaluated using in vitro assay systems: iron-chelating activity (Fe2+), inhibition of the radical 1-1-diphenyl-2-picrylhydrazyl (DPPH) and inhibition of production of thiobarbituric acid reactive substances (TBARS). In quantifying compounds by HPLC-DAD showed that the compounds rutin and quercetin showed the highest peaks in the three samples tested. Regarding carotenoids, the ß-carotene stood in the analyze. The methanolic fraction of lyophilized pulp of green fruits showed better results for iron chelation and DPPH tests; TBARS by the methanolic fraction of the ripe fruits showed lower IC50 as the basal. When in the presence of iron as an inducer of peroxidation, the methanolic fraction of the pulp of green fruits showed the lowest IC50. Our research indicates that the o fruits of M. glabra good potential in scavenging free radicals and can be an important source of antioxidant phytochemical.

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A proposta do artigo e abrir uma discussao entre a formulacao freudiana sobre o canibalismo, junto com a interpretacao do antropologo Eduardo Viveiros de Castro para o 'canibalismo ascetico' (ritual) dos Arawete (Guarani) e as atuais colocacoes dos psicanalistas pos-klenianos sobre a existencia de um narcisismo destrutivo. O texto sobre o qual se apoia essa discussao e o da Dissertacao de Mestrado de Teixeira (1993), que aponta o tema, deixando-o em aberto, como sendo um dos muito vertices sobre os quais se apoiaria a identidade nacional brasileira. Os autores enfatizam apenas o angulo do narcisismo destrutivo.

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