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A simple and miniaturized protocol was developed for chloride extraction from Brazilian pre-salt crude oil for further salt determination by colorimetry. In this protocol, the colorimetric analysis of chloride using digital images was carried out in an aqueous phase obtained after a simple and miniaturized extraction carefully developed for this purpose. A portable device composed of a homemade 3D-printed chamber with a USB camera was used. The PhotoMetrix app converted the images into RGB histograms, and a partial least squares (PLS) model was obtained from chemometric treatment. The sample preparation was performed by extraction after defining the best conditions for the main parameters (e.g., extraction time, temperature, type and volume of solvent, and sample mass). The PLS model was evaluated considering the coefficient of determination (R2) and the root mean square errors (RMSEs)—calibration (RMSEC), cross-validation (RMSECV), and prediction (RMSEP). Under the optimized conditions, an extraction efficiency higher than 84% was achieved, and the limit of quantification was 1.6 mg g−1. The chloride content obtained in the pre-salt crude oils ranged from 3 to 15 mg g−1, and no differences (ANOVA, 95%) were observed between the results and the reference values by direct solid sampling elemental analysis (DSS-EA) or the ASTM D 6470 standard method. The easy-to-use colorimetric analysis combined with the extraction method's simplicity offered a high-throughput, low-cost, and environmentally friendly method, with the possibility of portability. Additionally, the decrease in energy consumption and waste generation, increasing the sample throughput and operators' safety, makes the proposed method a greener approach. Furthermore, the cost savings make this a suitable option for routine quality control, which can be attractive in the crude oil industry. [ABSTRACT FROM AUTHOR]

Early soybean yield estimation has become a fundamental tool for market policy and food security. Considering a heterogeneous crop, this study investigates the spatial and spectral variability in soybean canopy reflectance to achieve grain yield estimation. Besides allowing crop mapping, remote sensing data also provide spectral evidence that can be used as a priori knowledge to guide sample collection for prediction models. In this context, this study proposes a sampling design method that distributes sample plots based on the spatial and spectral variability in vegetation spectral indices observed in the field. Random forest (RF) and multiple linear regression (MLR) approaches were applied to a set of spectral bands and six vegetation indices to assess their contributions to the soybean yield estimates. Experiments were conducted with a hyperspectral sensor of 25 contiguous spectral bands, ranging from 500 to 900 nm, carried by an unmanned aerial vehicle (UAV) to collect images during the R5 soybean growth stage. The tests showed that spectral indices specially designed from some bands could be adopted instead of using multiple bands with MLR. However, the best result was obtained with RF using spectral bands and the height attribute extracted from the photogrammetric height model. In this case, Pearson’s correlation coefficient was 0.91. The difference between the grain yield productivity estimated with the RF model and the weight collected at harvest was 1.5%, indicating high accuracy for yield prediction.

Article highlights - Inga edulis offer potential for biotechnological and environmental applications. - High protein and carbohydrate content in seeds support diverse agro-industrial uses. - edulis seeds enhance environmental education via forest nurseries schools. - Biotechnological potential of I. edulis seeds extends to ecosystem services. Abstract Inga edulis Martius is a native species of the Amazon Forest with great potential for urban afforestation in the cities of the Brazilian Amazon and widely used for the recovery of degraded areas. It is commonly cultivated by the Amazonian population for its edible fruit, quality wood, and excellent agroforestry components. This study aimed to select the matrices and obtain information about the behavior of the seeds in terms of drying, biometry, purity and germination, and chemical composition. The seeds collected in the environmental education action were recognized about potentialities of use for biotechnological products and environmental protection. The seed exploitation of this species is attractive due to its composition (protein and carbohydrates) and forest integration. I. edulis seedlings in the schools contribute to environmental education as a sustainable practice with biotechnological potential for the Amazon region.

Abstract Aim This study aims to analyze the scientific literature on phytoplankton in assessing lake water quality, based on bibliometric and network techniques. Methods PRISMA criteria were adopted to produce reliable results. The Scopus and Web of Science databases were consulted to retrieve the documents to be studied. The number of publications, citations and bibliographic coupling were techniques used to identify relevant journals, countries, authors, and articles. The conceptual evolution was analyzed by keywords co-occurrence and thematic mapping. Results Based on 2429 documents selected from the 1973-2023 annual period, the main results indicated 519 journals, 6450 authors, 54907 references, and 4844 keyword authors, among others. The annual growth index was 10.27%, reflecting the upward trend at the time. Erick Jeppesen resulted as the top influential author, China leaded in publications and collaborations with The United States of America. Hydrobiologia was the top journal. Top influential articles content theme related to cyanobacterial blooms. According to the results of the analysis of the conceptual framework, phytoplankton, water quality, eutrophication, and cyanobacteria were the most relevant themes. Furthermore, the trending topics were mainly climate change and degradation. Conclusions This comprehensive analysis allowed us to interpret the development of research related to the subject of assessing lake water quality.

Abstract This article analyzes the operational variables of a catalytic cracking plant that affect the catalytic circulation and conversion results. It is considered that the analysis of the impact of these variables on the catalytic circulation is essential for the refiner to determine the best operational strategies, without loss of profitability and to minimize friction mechanisms, which reduce particulate emissions. The Analysis of Variance revealed how, statistically, the parameters are related, presenting equal, opposite directions and with different magnitudes. The results of R2, F significances and analysis of residuals showed an excellent fit of the model, therefore, validating the design of the experiments carried out. The application model demonstrated a reduction capacity of 25% in the circulation of the catalyst, with no impact on the conversion of the unit. This result demonstrates the refiner's ability to act, improving its unit optimization techniques from an environmental and economic bias.

The use of fabric in reinforcing cement-based materials expands their applications for various types of construction elements. Additionally, employing renewable sources of plant-based fabrics contributes to reducing the environmental impact of the construction industry. However, the variability in the properties of plant fibers and fabrics necessitates prior studies to confirm their effectiveness as reinforcement materials. In this study, a new sisal fabric was produced and utilized as reinforcement in cement-based matrix composites. The sisal fibers, yarns, and fabrics produced were tested under direct tension. Five composites were manufactured by manual lamination, with reinforcement ranging from one to five layers, and were subjected to direct tension and flexural testing. The results indicate that, while the fiber shows brittle failure, the yarn and fabric exhibit a gradual loss of strength after reaching the maximum tension. All composites display strain-hardening and deflection-hardening behavior, with multiple cracking and an increase in tension and deformation before rupture. The mechanical properties exhibited improvement with an increase in the number of layers, and composites with four and five layers displayed distinct behavior, demonstrating increased stiffness after the occurrence of multiple cracking and a better mechanical performance, qualifying them for use as a construction element.

In this review, a thorough approach was taken to the therapeutic potential of CBD and the possibilities of heterologous expression for its synthesis. Synthesizes the most recent discoveries on the medicinal benefits of CBD, its mode of action, and different methodologies that aim to maximize CBD production using heterologous expression systems. This review contributes to increasing knowledge about the wide range of uses of CBD and its potential in industries, including biotechnology and medicine.

Abstract In pursuit of potential agents to treat Chagas disease and leishmaniasis, we report the design, synthesis, and identification novel naphthoquinone hydrazide-based molecular hybrids. The compounds were subjected to in vitro trypanocide and leishmanicidal activities. N’-(1,4-Dioxo-1,4-dihydronaphthalen-2-yl)-3,5-dimethoxybenzohydrazide (13) showed the best performance against Trypanosoma cruzi (IC50 1.83 µM) and Leishmania amazonensis (IC50 9.65 µM). 4-Bromo-N’-(1,4-dioxo-1,4-dihydronaphthalen-2-yl)benzohydrazide (16) exhibited leishmanicidal activity (IC50 12.16 µM). Regarding trypanocide activity, compound 13 was low cytotoxic to LLC-MK2 cells (SI = 95.28). Furthermore, through molecular modeling studies, the cysteine proteases cruzain, rhodesain and CPB2.8 were identified as the potential biological targets.

AbstractA portable device for digital image colorimetry (DIC) is reported for the determination of Ca in crude oil emulsions. ASTM D4807 was used for sample preparation for the isolation of saline species containing Ca. DIC was evaluated based on the complexation reactions with Ca using calcein, murexide, and calcon. Partial least squares (PLS) provided the best determination coefficients (higher than 0.990) for all complexing reagents. Significant interference of Mg was observed for the determination of Ca using calcein. PLS models with the lowest root mean square error of cross validation (RMSECV) values were obtained for murexide and calcon for a concentration of 0.250 mmol L−1 at pH of 13. The best conditions for camera focal length were 11 and 2 mm for murexide and calcon. For light intensity, the optimized conditions for murexide and calcon was 180 lux. Stabilities of color complexes over the time were 30 and 15 min for murexide and calcon, respectively. DIC/murexide provided the lowest root mean square error of prediction (RMSEP) and a linear response was observed from 0.5 to 10 mg L−1 Ca and the relative standard deviation (RSD) was lower than 10%. Significant differences were not observed between the results obtained by DIC/murexide and those obtained by microwave-assisted wet digestion (MAWD) with determination by inductively coupled plasma-optical emission spectrometry (ICP-OES). A limit of quantification of 0.50 mg kg−1 Ca were obtained using DIC/murexide. This approach is an alternative and useful method for the determination of Ca in crude oil samples, with advantages of miniaturization, low cost, and ease of operation. [ABSTRACT FROM AUTHOR]