Carlos Eduardo

Delcy Rodríguez held a meeting with the technical and scientific staff of Intevep and part of the PDVSA board of directors.

Lignocellulosic residues represent a promising source of raw material for obtaining several high-value bioproducts, including cellulose and derivatives. One of the main barriers to cellulose extraction from these residues is the presence of other components associated with the cellulose matrix, such as lignin and hemicellulose. To overcome this limitation, it is necessary to apply specific treatments to remove these constituents. In this study, the effectiveness of three chemical treatment methods in the purification of cellulose extracted from urban pruning biomass of the species Clitoria fairchildiana were evaluated, namely (i) alkaline treatment using dilute sodium hydroxide solution; (ii) alkaline treatment followed by bleaching with hydrogen peroxide; and (iii) alkaline treatment followed by bleaching with hydrogen peroxide and sodium hydroxide combined. The changes in chemical composition and thermal properties caused by each method were analyzed using techniques such as Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The results demonstrated that the biomass pretreatment reduced the content of impurities, lignin, and hemicellulose, increasing the cellulose content to 37.16% in the combined treatment (H2O2 + NaOH). Furthermore, the FTIR spectra revealed characteristic bands of important functional groups, which reaffirmed the chemical structure of the extracted cellulose through the identification of hydroxyl, carbonyl groups, and C-H bending vibrations. Additionally, the SEM results indicated an increase in specific surface area and greater exposure of fibrils, providing visual confirmation of the removal of constituents from the cellulosic matrix. Collectively, these results demonstrate the potential of combined chemical treatments for the valorization of Clitoria fairchildiana biomass and indicate its technical feasibility for obtaining cellulose with a higher degree of purity.

This systematic review aims to describe the current state of research on soil remediation utilizing digestates inoculated with fungi, as a cost-effective alternative. This study was performed according to the PRISMA 2020 guidelines, and nine papers were finally selected for review. The application of digestates augments the soil microbial community in terms of bacterial strains, mycorrhizal colonization, and enzymes. Digestates inoculated with fungi have notable impacts on soil stabilization. Some authors reported an improvement of up to 100% in plant growth when using digestates. HM removal rates of 17% for Si, 40% for Cd, and up to 80% for Pb have been achieved. Antibiotics and PFCAs showed low or no accumulation. The biomass source used for anaerobic digestion has a very important impact on the resulting digestate's quality and effect in soils: the use of cattle manure resulted in an increase in biomass yield from 9% up to 100% when compared to manure co-digested with organic wastes. The fungal strain, environmental conditions, and existing contaminants must be considered with respect to the specific practical application. These insights can contribute to the management of environmental risks and the prevention of negative impacts on human health, ecosystems, and the economy.

Teleost fish are the first evolutionary group to exhibit an innate and adaptive immune system. Within the mechanisms of adaptive immunity, fish possess, among others, T-helper cells (CD4-like) and their differentiation machinery, regulated by the master transcription factors T-bet, GATA3, Foxp3, and RORγ. Many studies support the existence of a non-neuronal cholinergic system involved in the immune response, named after the ability of leukocytes to synthesize de novo acetylcholine (ACh). Organophosphorus pesticides (OPs), such as diazoxon (DXN), are examples of compounds that act as cholinergic disruptors with immunotoxic effects. The present study aimed to evaluate the expression of transcription factors in leukocytes (spleen mononuclear cells, SMNCs) of Nile tilapia by modulating cholinergic pathways in immune cells using agonists, antagonists, and diazoxon (DXN), an anticholinesterase substance. The obtained data showed a significant increase in RORγ mRNA expression upon stimulation with the nicotinic agonist, whereas activation of the muscarinic receptor with its agonist increased T-bet mRNA expression. An alteration in RORγ expression levels induced by DXN exposure was also observed. The results suggest a probable directing of the immune response towards a pro-inflammatory profile orchestrated mainly by RORγ and T-bet transcription factors in response to cholinergic stimuli.

Laboratorio de Invenciones Aplicadas a la Industria (LIAI), Unidad Académica de Ingeniería Eléctrica, Universidad Autónoma de Zacatecas, Zacatecas 98600, Zacatecas, Mexico

Artificial intelligence (AI) has become a strategic technology for global health, with increasing relevance amid the climate emergency and persistent digital inequalities. This study examines how AI has been applied in Brazilian healthcare through a scoping review with an in-depth methodological synthesis, focusing on Transfer Learning (TL) and Federated Learning (FL) as approaches to address data scarcity, privacy, and technological dependence. We searched PubMed, SciELO, and the CNPq Theses and Dissertations Repository for peer-reviewed studies on AI applications in Brazil, screened titles using AI-assisted tools with manual validation, and analyzed thematic patterns across methodological and infrastructural dimensions. Among 349 studies retrieved, six explicitly used TL or FL. These techniques were frequently implemented through multi-country research consortia, demonstrating scalability and feasibility for collaborative model training under privacy constraints. However, they remain marginal in mainstream practice despite their ability to deploy AI solutions with limited computational resources while preserving data sovereignty. The findings indicate an emerging yet uneven integration of resource-aware AI in Brazil, underscoring its potential to advance equitable innovation and digital autonomy in health systems of the Global South.

Antimicrobial resistance (AMR) represents a major global health challenge, driving the search for novel antimicrobial compounds from natural sources. Filamentous fungi are prolific producers of bioactive metabolites, yet the biological potential of fungal guttation droplets remains relatively underexplored. In this study, guttation droplets produced by Penicillium pimiteouiense and Penicillium menonorum, isolated from rhizospheric soils of Opuntia spp. in Colima, Mexico, were evaluated for antibacterial activity against clinically relevant pathogens. Fungal isolates were identified through macromorphological characterization and sequence analysis of ITS and β-tubulin genes. Antibacterial activity of the guttation droplets was evaluated using agar well diffusion and microbroth dilution assays to determine inhibition zones, minimum inhibitory volume (MIV), and minimum bactericidal volume (MBV). The exudates exhibited measurable activity against several Gram-negative and Gram-positive bacteria, including Escherichia coli, Salmonella enterica, Klebsiella pneumoniae, Serratia marcescens, and Staphylococcus aureus. Guttation droplets from P. pimiteouiense showed the highest inhibition, with zones up to 24.4 mm against S. enterica, and activity comparable to gentamicin. MBV/MIV ratios indicated bactericidal activity against selected pathogens, including E. coli, K. pneumoniae, and S. aureus. These findings demonstrate that fungal guttation droplets represent a promising and underexplored source of antibacterial compounds and support their potential for antimicrobial discovery.

An inventory of tree-animal interactions shows that 80% of Amazonian tree species rely on animals for both pollination and seed dispersal, and less than 1% are free from animal involvement in these key life stages.

The Chamber's estimates suggest that the country's economic growth could be in the range of between 6% and 8%.