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Synthesis and evaluation of the antifungal and antibiofilm potential of aminochalcones
No full textCandida is a commensal fungus of clinical interest that commonly lives in oral cavity and intestine but can become an opportunist microrganism and cause severe infections. A serie of 10 aminochalcones were designed and synthetized to obtain compounds anti-Candida with potent and broad-spectrum activity. The most active compound J34 demonstrated excellent in vitro activity against Candida albicans, Candida tropicalis, Candida parapsilosis, Candida glabrata and Candida krusei with minimum inhibitory concentration between 1.9 and 7.8 µg/mL. The association of aminochalcone J34 with amphotericin B demonstrated synergistic effect against C. albicans, with Fractional Inhibiroty Concentration Index (FICI) value of 0.5. Subinhibitory concentration of J34 inhibited the C. albicans adhesion to human keratinocytes. Treatment with J34 reduced C. albicans biofilm formation, as well as acts on preformed biofilm in concentration-dependent mode. Time-kill curve demonstrated that J34 had fungicidal action after 12 h of treatment. Preliminary mechanism of action study showed J34 interacts with membrane ergosterol but does not act on fungal cell wall of C. albicans. In additon, in vivo studies using Galleria mellonella indicated low toxic effect of chalcone J34 after 72 h of treatment.Department of Chemistryand Environmental Sciences Institute of Biosciences Humanities and Exact Sciences São Paulo State University Júlio de Mesquita Filho, SPDepartment of Physiological Sciences Piracicaba Dental School University of Campinas, SPDepartment of Chemistryand Environmental Sciences Institute of Biosciences Humanities and Exact Sciences São Paulo State University Júlio de Mesquita Filho, S
Germinação e controle do crescimento de girassol ornamental cultivado em tela fotoconversora utilizando diferentes doses de ácido giberélico
No full textHelianthus annuus L., commonly known as the dwarf sunflower, has become popular in the ornamental flower market in Brazil, increasing its demand in floriculture retail. It is one of the most commercialized flowers. In addition to its unique characteristics, such as its inflorescence and vibrant petal color, it is a hardy plant that adapts to the different environments. However, excessive sunlight can harm its floral composition, affecting its appearance and marketability. Various management strategies have been adopted to achieve adequate productivity and meet market demands. These strategies include applying gibberellic acid to increase seed germination, and using photoconverter screens to minimize sunlight-induced damage to petals by altering light spectrum and intensity and converting direct radiation into diffuse radiation without impairing plant development and photosynthesis. Two consecutive experiments were conducted in this study. The first aimed to determine the optimal gibberellic acid dose by observing the germination speed index, and quantifying normal and abnormal seedlings. Four different doses (0, 100, 250, and 500 mg L−1 of gibberellic acid) were tested with four replicates. The second experiment aimed to verify the ideal color of photoconverter screen by comparing three treatments, including the control (without using photoconverter screens), a red photoconverter screen, and a silver photoconverter screen. Ten replicates were used, assessing agronomic traits essential for the commercial value of plants, such as plant height, stem diameter and length, root length, and relative growth rate of the plant. The experiments were conducted in the municipality of Dracena, São Paulo, Brazil. The first experiment was performed in a completely randomized design, while the second in a randomized block design, in a greenhouse with automatic irrigation. The results indicated that for dwarf sunflower seeds, the optimal dose of gibberellic acid was 500 mg L−1, which achieved 100% germination after seven days and significantly differed from the lower doses for normal plants and plant length. This optimal dose was used in seed treatment for the second experiment. The results revealed that the use of both red and silver photoconverter screens improved the development of plants, increasing their height, stem diameter, and stem length, fundamental traits required for their commercialization, while improving the development and relative growth rate.Course of the Postgraduate Program in Agronomy The Universidade Estadual Paulista “Júlio de Mesquita Filho” Faculdade de Engenharia UNESP FEIS, SPFaculdade de Ciências Agrárias e Tecnológicas UNESP FCAT, SPUNESP FCAT Department of Plant Production, SPUNESP FCAT Department of Animal Production, SPCourse of the Postgraduate Program in Agronomy The Universidade Estadual Paulista “Júlio de Mesquita Filho” Faculdade de Engenharia UNESP FEIS, SPFaculdade de Ciências Agrárias e Tecnológicas UNESP FCAT, SPUNESP FCAT Department of Plant Production, SPUNESP FCAT Department of Animal Production, S
Use of adjuvants in the retention of copper formulations after simulated rainfall on soybean
No full textA cultura da soja (Glycine max (L.) Merr.) possui relevante importância econômica no cenário nacional, estando sujeita a diversos fitopatógenos que comprometem significativamente sua produtividade. Entre as estratégias de controle, destaca-se a aplicação de fungicidas, cuja eficiência pode ser prejudicada por fatores ambientais, como a ocorrência de chuvas após a pulverização. Este trabalho teve como objetivo avaliar a retenção de adjuvantes comerciais (SkyPro e UltraBio) na aplicação de fungicida cúprico (oxicloreto de cobre) em folhas de soja com uma taxa de aplicação de 80 l/ha, submetidas à simulação de diferentes volumes de chuva (0 mm, 5 mm e 10 mm). Foram conduzidos dois experimentos em casa de vegetação, em delineamento em blocos ao acaso, com esquema fatorial 3 × 3 + 1 (calda sem adjuvante, com SkyPro e com UltraBio; chuva de 0mm, 5mm e 10mm, mais a testemunha) e, análises baseadas no depósito de cobre retido nas folhas e na cobertura superficial da aplicação. Os resultados indicaram que a formulação utilizada permaneceu retida nas folhas, mesmo na ausência de adjuvantes, e que os volumes de chuva simulada não promoveram variações na retenção do fungicida. Além disso, a adição dos adjuvantes não demonstrou aumento no depósito e na cobertura foliar, não houve efeito significativo dos adjuvantes, mostrando que a recomendação do uso de adjuvantes deve considerar as condições ambientais e as características do produto aplicado. Conclui-se que, a formulação cúprica utilizada possui resistência à lavagem sem e com o uso de adjuvantes. Palavras-chave: chuva simulada, cobertura superficial, depósito foliar, fungicidas cúpricos, tecnologia de aplicação.Soybean cultivation (Glycine max (L.) Merr.) has significant economic importance in the national context and is susceptible to various phytopathogens that can severely compromise its productivity. Among the control strategies, the application of fungicides stands out, although their efficiency can be reduced by environmental factors, such as rainfall occurring after spraying. This study aimed to evaluate the retention of
commercial adjuvants (SkyPro and UltraBio) in the application of copper fungicide (copper oxychloride) on soybean leaves at an application rate of 80 L/ha, subjected to simulated rainfall volumes (0 mm, 5 mm, and 10 mm). Two experiments were conducted in a greenhouse, using a randomized block design with a 3 × 3 + 1 factorial scheme (spray solution without adjuvant, with SkyPro, and with UltraBio; rainfall of 0
mm, 5 mm, and 10 mm, plus an untreated control), and analyses were based on the copper deposition retained on the leaves and the surface coverage of the application. The results indicated that the formulation remained adhered to the leaves even in the absence of adjuvants, and the simulated rainfall volumes did not cause variations in fungicide retention. Furthermore, the addition of adjuvants did not increase deposition or leaf surface coverage, showing no significant effect, which suggests that the recommendation for adjuvant use should consider environmental conditions and the characteristics of the applied product. It is concluded that the copper formulation used is resistant to wash-off both with and without adjuvants.
Keywords: simulated rainfall, surface coverage, foliar deposition, copper fungicides, application technology
A neural network approach employed to classify soybean plants using multi-sensor images
No full textCounting soybean plants is a crucial strategy for assessing sowing quality and supporting high production. Despite its importance, the laborious nature of traditional assessment methods makes them unreliable and not scalable. Additionally, innovative image-based solutions have demonstrated limitations in detecting dense crops such as soybeans. Therefore, in this study, we developed neural network models to analyze a set of RGB and multispectral images and perform plant classification in a comprehensive dataset, which included data collected at three vegetative stages of soybean (VC, V1, and V2). Our results demonstrated high accuracy in classifying plants using either RGB (98%) or multispectral images (92%). A significant strength of this study is the ability to classify highly dense plants, without a trend for misclassification. Clearly, our findings provide stakeholders with a timely and effective approach to counting soybean plants, reducing labor and time, while increasing reliability.Department of Plant Science and Landscape Architecture University of Connecticut, StorrsSchool of Plant Environmental and Soil Sciences Louisiana State UniversityDepartment of Rural Engineering São Paulo State University, SPPrecision AgX, PO box 9617University Center of Herminio Ometto Foundation, SPDepartment of Horticulture University of GeorgiaDepartment of Rural Engineering São Paulo State University, S
Investigating Pb Nanostructures with a Density-Functional Tight-Binding Approach: Slater-Koster Parameters
No full textIntercalation in epigraphene systems is an established technique widely used to modify the electronic structure of graphene and to synthesize otherwise unstable two-dimensional layers with exotic electronic properties. However, capturing the full symmetry of the heterostructure requires a large number of atoms, rendering traditional electronic-structure approaches computationally demanding. Density-functional-based tight-binding (DFTB) offers an efficient alternative, balancing accuracy and reduced computational cost. For heavy elements such as Pb, however, proper parameters for these types of calculations are not available in the open literature. In this work, we developed a Slater-Koster parameter set for the elements Si, C, and Pb, enabling the investigation of the electronic structure of various elemental and binary solid-state structures, such as graphene, plumbene, and silicon carbide. Our results obtained with DFTB for bulk Pb and Pb/SiC structures show good qualitative agreement with pure DFT calculations. Furthermore, the inclusion of spin-orbit coupling (SOC) significantly modifies their electronic properties, aligning with DFT findings. These results underscore the capability of the optimized parameters to accurately model complex systems, allowing investigations of larger systems closer to experimental observations.Technische Universität Chemnitz Institut für PhysikDepartamento de Física Universidade Estadual Paulista Instituto de Geociências e Ciências ExatasDepartamento de Física Universidade Estadual Paulista Instituto de Geociências e Ciências Exata
Soybean crop response to phosphorus sources and phosphate-solubilizing bacteria
No full textO Brasil é o maior produtor global de soja, sendo de suma importância o manejo adequado da nutrição e adubação, onde o fósforo (P) é um nutriente essencial para o crescimento e produtividade desta leguminosa. O objetivo deste trabalho foi avaliar o efeito da adubação fosfatada com fontes convencionais e de grânulos revestidos, além da inoculação com bactérias solubilizadoras de fosfato na cultura da soja. O experimento foi conduzido em Jaboticabal (SP), utilizando o delineamento experimental em blocos casualizados, com quatro repetições. O primeiro fator de estudo foi o uso de quatro fontes de P aplicadas no sulco de semeadura: Fosfato Monoamônico (MAP) e Superfosfato Triplo (SFT), ambas convencional e com grânulos revestidos. O segundo fator consistiu no uso de inoculante na semente com bactérias solubilizadoras de fosfato (Pantoea agglomerans): sem aplicação e com aplicação utilizando 50 gramas por hectare. Foi adicionado dois tratamentos testemunhas: sem a aplicação de P no sulco de semeadura x sem e com o inoculante na semente. As respostas das plantas foram avaliadas por meio do crescimento, nutrição e produtividade da soja. Os dados foram analisados por meio de análise de variância pelo teste F e para comparação de médias utilizou-se o teste de Tukey a 5% de probabilidade. Desse modo, as maiores produtividades de grãos da cultura da soja foram obtidas com as fontes de fertilizantes fosfatados SFT convencional e MAP com grânulos revestidos, associados ao uso de inoculante com as bactérias solubilizadoras de fosfato na semente, promovendo reflexos positivos na produtividade de grãos.Brazil is the world’s largest soybean producer, making proper nutrient management and fertilization essential, particularly phosphorus (P), which is a key nutrient for the growth and productivity of this legume. The objective of this study was to evaluate the effect of phosphorus fertilization using conventional and coated granule sources, as well as inoculation with P-solubilizing bacteria on soybean cultivation. The experiment was conducted in Jaboticabal (SP), using a randomized block design (RBD) with four replications. The first factor studied was the use of four P sources applied in the planting furrow: Monoammonium Phosphate (MAP) and Triple Superphosphate (TSP), both in conventional and coated forms. The second factor involved seed inoculation with phosphate-solubilizing bacteria (Pantoea agglomerans): without and with application at 50 grams per hectare. Additionally, two control treatments were included: without P application in the planting furrow × without and with seed inoculant. Plant responses were evaluated based on growth, nutrition, and soybean yield. Data were analyzed using analysis of variance (ANOVA) with the F-test, and mean comparisons were performed using Tukey’s test at a 5% significance level. The highest grain yields were obtained with conventional TSP and coated MAP fertilizers, combined with seed inoculation using phosphate-solubilizing bacteria, showing positive effects on soybean grain productivity.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Decentralized and cost-effective colorimetry analysis by smartphone-based method digital image for monitoring electrochemical elimination of dye from water matrices
No full textThe present research provides a newly developed method that aims at versatile, rapid, portable, and low-cost instrumental protocol for colorimetric analysis of waters, polluted by dyes, through the use of a smartphone and app that detects and represents the RGB (red, green, and blue) color model. The calibration of the method is based on RGB values obtained by capturing images of colored solutions with known concentrations. The method was spectrophotometrically validated by analyzing the same samples, reaching more than 95% of accuracy. The utilization of this smartphone-based method for colorimetric analysis was proposed to follow, for the first time, the electrochemical treatment of different water matrices (400 mL of synthetic and real) with substantial organic and salts content (50 mg L−1 of methylene blue in 0.1 mol L−1 Na2SO4) using boron-doped diamond (BDD) anode by applying current densities (j) of 15, 30, and 60 mA cm−2. Discoloration results (which were achieved with this novel smart water security solution) clearly showed that significant removal efficiencies were achieved in 2 h, depending on the j, when synthetic and real effluents were used. A key role was played by the sulfates in solution which were electroconverted to persulfates via reaction with •OH produced at BDD surface, enhancing the oxidation power of the electrochemical treatment. Then, the procedure presented here obtained a high level of confidence representing great support for scientific laboratories as an alternative that can replace the use of expensive spectrophotometers.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Renewable Energies and Environmental Sustainability Research Group Institute of Chemistry Federal University of Rio Grande do Norte, Campus Universitário, Av. Salgado Filho 3000, Lagoa Nova, CEP 59078-970, Rio Grande do NorteSchool of Science and Technology Federal University of Rio Grande do Norte, Av. Senador Salgado Filho 3000, Lagoa Nova, Rio Grande do NorteNational Institute for Alternative Technologies of Detection Toxicological Evaluation and Removal of Micropollutants and Radioactives (INCT–DATREM) Institute of Chemistry UNESP, P.O. Box 355, São PauloNational Institute for Alternative Technologies of Detection Toxicological Evaluation and Removal of Micropollutants and Radioactives (INCT–DATREM) Institute of Chemistry UNESP, P.O. Box 355, São PauloCNPq: 150933/2021-5FAPESP: 2014/50945-4FAPESP: 2019/13113-4CNPq: 306323/2018-4CNPq: 312595/2019-0CNPq: 315879/2021-1CNPq: 351605/2022-3CNPq: 408110/2022-8CNPq: 409196/2022-3CNPq: 439344/2018-
Genotype-Specific Physiological Responses of Sugarcane to Potassium Deficiency: Integrating K Nutritional Efficiency, Photosynthesis-Related Parameters and Sugar Partitioning
No full textPotassium (K) nutritional requirements for sugarcane (Saccharum spp.) is relatively high. However, genotypes differ in their K uptake efficiency (KUpE) and use efficiency (KUtE), which shapes differences in plant growth. The study aimed to gain insight into the physiological responses of two sugarcane genotypes (SP90-3414 and SP83-2847) growth under two K concentrations in the nutrient solution (low K = 1.0 mmol L−1 and adequate K = 6.0 mmol L−1). Total leaf area, root growth and photosynthesis-related parameters were not changed in SP83-2847, regardless K supply, while for SP90-3414 under low K supply, these parameters were dramatically decreased. Under either low or adequate K supply, SP83-2847 genotype has higher KUpE and KUtE (K use efficient genotype) relative to SP90-3414, showing similar shoot dry matter yield and shoot K accumulation. Moreover, SP83-2847 plants grown under low K supply showed the highest accumulation of total soluble sugar and sucrose in leaves. The enhanced K accumulation in the shoot (leaves and stem) and sugar content (soluble sugar and sucrose) in the leaves of SP83-2847 cultivar is a physiological strategy to ease K-induced deficiency stress.Centro de Energia Nuclear Na Agricultura Universidade de São Paulo, SPFederal Institute of Mato Grosso Do Sul, MSUniversidade Estadual Paulista “Julio de Mesquita Filho”, SPUniversidade Estadual Paulista “Julio de Mesquita Filho”, S
A novel artificial intelligence-powered tool for automated root canal segmentation in single-rooted teeth on cone-beam computed tomography
No full textAim: To develop and validate an artificial intelligence (AI)-powered tool based on convolutional neural network (CNN) for automatic segmentation of root canals in single-rooted teeth using cone-beam computed tomography (CBCT). Methodology: A total of 69 CBCT scans were retrospectively recruited from a hospital database and acquired from two devices with varying protocols. These scans were randomly assigned to the training (n = 31, 88 teeth), validation (n = 8, 15 teeth) and testing (n = 30, 120 teeth) sets. For the training and validation data sets, each CBCT scan was imported to the Virtual Patient Creator platform, where manual segmentation of root canals was performed by two operators, establishing the ground truth. Subsequently, the AI model was tested on 30 CBCT scans (120 teeth), and the AI-generated three-dimensional (3D) virtual models were exported in standard triangle language (STL) format. Importantly, the testing data set encompassed different types of single-rooted teeth. An experienced operator evaluated the automated segmentation, and manual refinements were made to create refined 3D models (R-AI). The AI and R-AI models were compared for performance evaluation. Additionally, 30% of the testing sample was manually segmented at two different times to compare AI-based and human segmentation methods. The time taken by each segmentation method to obtain 3D models was recorded in seconds(s) for further comparison. Results: The AI-driven tool demonstrated highly accurate segmentation of single-rooted teeth (Dice similarity coefficient [DSC] ranging from 89% to 93%; 95% Hausdorff distance [HD] ranging from 0.10 to 0.13 mm), with no significant impact of tooth type on accuracy metrics (p >.05). The AI approach outperformed the manual method (p <.05), showing higher DSC and lower 95% HD values. In terms of time efficiency, manual segmentation required significantly more time (2262.4 ± 679.1 s) compared to R-AI (94 ± 64.7 s) and AI (41.8 ± 12.2 s) methods (p <.05), representing a 54-fold decrease. Conclusions: The novel AI-based tool exhibited highly accurate and time-efficient performance in the automatic root canal segmentation on CBCT, surpassing the human performance.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Department of Restorative Dentistry School of Dentistry São Paulo State University (UNESP), São PauloOMFS IMPATH Research Group Department of Imaging and Pathology Faculty of Medicine University of LeuvenDepartment of Oral and Maxillofacial Surgery University Hospitals LeuvenDepartment of Propedeutics and Integrated Clinic Division of Oral Radiology School of Dentistry Federal University of Bahia (UFBA), BahiaDepartment of Dental Medicine Karolinska InstitutetDepartment of Restorative Dentistry School of Dentistry São Paulo State University (UNESP), São PauloFAPESP: 2020/11012-3FAPESP: 2021/11496-3FAPESP: 2022/13774-
Green solvent pretreatments for lignocellulosic biorefineries: A review
No full textGreen solvents have emerged as a promising alternative to efficiently fractionate lignocellulosic biomass, often reducing the environmental impact of the process. This review paper explores the potential of green solvents as sustainable alternatives for lignocellulosic biomass pretreatment in biorefineries. The study focused its discussion on four of the most prominent green solvent classes: deep eutectic solvents (DES), ionic liquids (IL), supercritical fluids (SFs), and biomass-derived solvents. It analyzes their efficiency in fractionating cellulose, hemicellulose, and lignin while emphasizing industrial scalability and environmental impact. Considering the body of work evaluated here, although viscosity and recyclability issues persist, DES demonstrated high tunability and low toxicity, achieving notable delignification and enzymatic hydrolysis enhancement. ILs exhibited superior selectivity and adaptability for lignocellulose dissolution but faced challenges of high synthesis costs and environmental concerns. SFs, particularly supercritical CO2 combined with co-solvents, proved effective for rapid biomass fractionation but require high energy input for extreme operating conditions. Biomass-derived solvents like γ-valerolactone (GVL) and Cyrene® showed promise for efficient lignin removal and cellulose preservation. However, their production processes need further optimization for sustainability. Overall, this review highlights advancements in green solvent technologies, identifying key challenges such as recyclability, cost reduction, and lifecycle environmental impacts. It calls for further research on optimizing solvent systems and exploring diverse biomass types to enhance industrial application and environmental viability.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)University of Campinas School of Chemical Engineering, Albert Einstein, Avenue, 500, São PauloUniversity of Campinas School of Food Engineering, Monteiro Lobato. Street, 80, São PauloSão Paulo State University School of Agricultural Sciences, Universitária Avenue, 3780, São PauloSão Paulo State University School of Agricultural Sciences, Universitária Avenue, 3780, São PauloCAPES: 001FAPESP: 21/11380-5FAPESP: 22/07277-7FAPESP: 22/15814-2CNPq: 302858/2022-9CNPq: 303063/2022-0CNPq: 304518/2022-