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Hydrotalcite materials (HTs) were synthesized by a facile and swift combined mechanochemistry/coprecipitation approach, and their catalytic activity was evaluated and compared with conventionally synthesized hydrotalcites (co-precipitation method) in the Knoevenagel condensation between furfural and ethyl cyanoacetate/malononitrile. Characterization and catalytic activity results clearly demonstrate that the proposed combined mechanochemical/coprecipitation approach provides an improvement in crystallinity, morphology, tunable basicity, and textural properties (higher surface area and enhanced surface properties) as compared to HTs obtained via conventional coprecipitation methods. In addition, mechanochemically synthesized HTs largely improve catalytic activities, including conversion and product selectivity to Knoevenagel condensation products under solventless conditions, short reaction times, or reaction at room temperature as compared to conventional counterparts (e.g., 30–40 vs > 99% product yields).

Highly functionalized, high value added bioactive molecules are generally obtained by synthetic procedures that are highly selective, economical, with high atom economy, and environmentally friendly. Following these guidelines, the use of recoverable solid catalysts, nonpolluting substrates, or toxic organic solvent contributes greatly to these demands. In the last three decades, heteropolyacids (HPAs) and its derivatives have received great attention as recyclable solid catalysts, due to their strong Brönsted acidity, excellent oxidizing capacity under mild conditions, and various reuse cycles without appreciable loss of their catalytic activity. However, new activation methods should be investigated to improve the sustainability of a process using HPAs. In this review, we report the latest advances associated with the synthesis of potentially bioactive molecules using more energy efficient alternatives such as microwaves, ultrasound, mechanochemistry, and photochemistry to minimize the energy consumption associated with organic synthesis. The transformations studied include construction reaction, heterocycle synthesis, selective oxidation, and biomass recovery.

Environment remediation is one of the primary goals of sustainable development and anthropogenic activities, and the use of fuels in various industrial processes through combustion has led to an increase in CO2 as well as big damage to the atmosphere by the greenhouse effect. Biochar has been used for the capture of carbon dioxide due to its high surface area. In this study, we obtained biochar from soursop seeds. The materials were synthesized by pyrolysis of precursor materials and chemical activation with chlorides of Ca and Mg at a concentration of 5% w/v. The effect of the defatting process of the soursop seeds on the obtained carbon was also researched. The absorbed solids were characterized through thermogravimetric analysis, X-ray diffraction, and CO2 adsorption, followed by infrared spectroscopy, N2-physisorption, CO2-physisorption, CO2, XPS, DRIFTS and TPD of NH3. The type of activating agent and pretreatment conditions used were more favorable than the defatted process at obtaining carbons with N2 surface areas between 26 and 220 m2g−1. The biochars were analyzed by CO2 surface area to describe the microporous framework, and the solid with the best CO2 surface area was the one with the highest CO2 adsorption. According to the statistical analyses conducted, the evaluated models Langmuir, Freundlich, and Redlich-Peterson presented good fits to the experimental data. However, the Redlich-Peterson model showed the lowest values for the residual variance, which were of the order of 0.001 or less in all cases based on the CO2 adsorption isotherms on the studied activated carbons. However, the carbons obtained by defatting showed favorable hydrophilic behavior along with adsorption capacities in the bioremediation process and affinity towards of this GHG. [ABSTRACT FROM AUTHOR]

The seabird intestinal microbiota, or bacteriome, predominantly consists of bacteria that establish during embryonic development through vertical transfer from females and horizontal transfer during growth and copulation. This study focuses on the Heermann's Gull (Larus heermanni), a seabird that breeds mainly within the Gulf of California. Our goal was to understand its gut bacteriome composition and its implications for conservation and public health. Using microbiological techniques, 16S rRNA gene sequencing, and mass spectrometry, we characterized the HG gut bacteriome and compared it with other bird species. Our findings reveal a diverse bacteriome, particularly in the intestine and rectum, with dominant phyla including Firmicutes, Proteobacteria, Bacteroidetes, Cyanobacteria, and Fusobacteria. Seasonal and sex-related differences were observed, with significant correlations between some pairs of bacteria. Notably, we identified various pathogens and potential zoonotic bacteria, underscoring the public health risks associated with Heermann's Gull interaction with humans and other animals. These results highlight the importance of the Heermann's Gull gut bacteriome in nutrient production, pathogen control, and digestive health, and emphasize the need for further research on pathogen transmission involving seabirds. Our study provides crucial insights for conservation strategies and underscores the role of wild birds in the epidemiology of zoonotic diseases. [ABSTRACT FROM AUTHOR]

We report the synthesis of alkyl 1,2,6‐triaryl‐4‐arylaminopiperidine‐3‐ene‐3‐carboxylates in acceptable yields (42%–71%) and high trans‐diastereoselectivity (69:31 to 100:0) through a one‐pot multicomponent reaction of aromatic aldehydes, aromatic amines, and β‐ketoesters catalyzed by phosphomolybdic acid in methanol at room temperature. The structure and stereochemistry of tetrahydropyridines were confirmed by X‐ray crystallography. This protocol stands out for its operational simplicity, the use of an inexpensive and commercially available heteropolyacid catalyst, low catalyst loading, and purification via simple filtration, resulting in acceptable yields and high diastereoselectivity. [ABSTRACT FROM AUTHOR]

The present study presents the results obtained from evaluating the photocatalytic behavior of a series of sulfated CeO2 materials in the photocatalytic degradation of the herbicide 2,4-dichlorophenoxyacetic acid. The CeO2 photocatalytic support was prepared using the precipitation synthesis method. Subsequently, the support was wetly impregnated with different contents of sulfate ions (0.5, 1.0, and 2.0 wt.%). The materials were characterized using X-ray diffraction, nitrogen physisorption, infrared spectroscopy, diffuse reflectance UV–Vis spectrophotometry, and thermal analysis. The characterization results showed that the sulfation of the material promoted an increase in the surface area and a decrease in the average size of the crystallites. Likewise, it was possible to demonstrate the surface sulfation of the support through bidentate coordination of the sulfate groups to the semiconductor metal. Concerning photoactivity, the convenience of the surface modification of CeO2 was confirmed because the sulfate groups acted as capturers of the electrons generated during the photocatalytic process, reducing the frequency of recombination of the charge carriers and allowing the availability of the gaps to favor the degradation reaction of the contaminant. Finally, it was evident that a percentage of 1.0 wt.% of the sulfate anion is the optimal content to improve the photocatalytic properties of CeO2. [ABSTRACT FROM AUTHOR]

This review examines the role of deep eutectic solvents (DESs) in the biorefinery process. It covers the characteristics and classification of two‐component DESs, their preparation methods, and their physicochemical properties. The various applications of DES systems in biomass pretreatment, including lignin and hemicellulose removal, production of cellulose nanofibers, and the extraction of proteins, lipids, and phenolic compounds, among others, are explored. The synthesis of platform molecules using DES is also discussed. Finally, this review provides some tools that may be useful for researching the involvement of DES systems in high‐ or low‐biomass biorefineries. [ABSTRACT FROM AUTHOR]

The genus Mucuna is a potential protein source, but it has been underutilized due to the presence of antinutritional factors, especially L-DOPA. Solid-state fermentation with lactic acid bacteria could be an effective and simple method for reducing these antinutritional factors while simultaneously enriching the protein content. In this work, an experimental analysis identified the variables with the greatest influence on the solid-state fermentation of Mucuna deeringiana. In general, we observed a decrease in pH due to the production of and increase in lactic acid, resulting in a 91% (6.40 to 0.55 g/100 g sample) reduction in L-DOPA, 51% decrease in phenolic compounds (11.65 to 5.70 g/100 g sample), 97% decrease in tannins (1.26 to 0.04 g/100 g sample), and the antioxidant capacity of the fermented flour was 97%, with an increase in protein content of 12%. Furthermore, it demonstrated greater stability over 24 days compared to the control samples, which remained stable for only 3 days. These results suggest that the bacterium has a positive effect on the production of lactic acid, and the nutritional composition can be enhanced by reducing antinutritional factors, especially L-DOPA, that limit the use of this legume. This process proves to be a cost-effective and sustainable method for developing nutritious feed products derived from Mucuna flours. [ABSTRACT FROM AUTHOR]

Furfural is a well-recognized biomass platform. Hydrogenation and reductive amination of furfural are two principal routes in the valorization of this compound. In both reactions, the presence of reducible species (SMSI effect) and acid sites could favor the selectivity toward some interesting products. Both conditions could be obtained using metal particles supported on reducible mixed oxides. In this work, we investigate the use of Pt/Nb2O5-Al2O3 catalysts for the hydrogenation and reductive amination of furfural at distinct Nb2O5 contents. A decaniobate salt was used as a precursor of Nb2O5. The solids were reduced at 500 °C to assure the migration of reducible NbOx species. The solids were characterized by XRD, Raman spectroscopy, HR-TEM, N2-physisorption, NH3-TPD and Pyr-DRIFTS. The results showed that higher Nb2O5 loadings led to a lower distribution of Al2O3 and Pt, favoring the catalysts' acidity. This fact implies that large particle size and the presence of Nb2O5 islands favor the formation of furfuryl alcohol but have a detrimental effect on the amine formation in the reductive amination of furfural. [ABSTRACT FROM AUTHOR]

During the COVID-19 pandemic, nonpharmaceutical interventions (NPIs) were implemented in order to control the transmission of SARS-CoV-2, potentially affecting the prevalence of respiratory syncytial virus (RSV). This review evaluated the impact of NPIs on RSV-related hospitalizations in children during the lockdown (2020–2021) compared to the pre-pandemic (2015–2020) and post-lockdown (2021–2022) periods. In this systematic review and meta-analysis, we searched through PubMed, Scopus, and Web of Science for studies published in English between 1 January 2015 and 31 December 2022. Additionally, we conducted hand searches of other records published between 1 January 2023 and 22 January 2024. Our target population was hospitalized children aged 0–18 years with RSV-related lower respiratory tract infections confirmed through immunofluorescence, antigen testing, or molecular assays. We focused on peer-reviewed observational studies, analyzing the primary outcome of pooled RSV prevalence. A generalized linear mixed model with a random-effects model was utilized to pool each RSV prevalence. Heterogeneity was assessed using Cochran's Q and I2 statistics, while publication bias was evaluated through funnel plots and Egger's tests. We identified and analyzed 5815 publications and included 112 studies with 308,985 participants. Notably, RSV prevalence was significantly lower during the lockdown period (5.03% [95% CI: 2.67; 9.28]) than during the pre-pandemic period (25.60% [95% CI: 22.57; 28.88], p < 0.0001). However, RSV prevalence increased notably in the post-lockdown period after the relaxation of COVID-19 prevention measures (42.02% [95% CI: 31.49; 53.33] vs. 5.03% [95% CI: 2.67; 9.28], p < 0.0001). Most pooled effect estimates exhibited significant heterogeneity (I2: 91.2% to 99.3%). Our findings emphasize the effectiveness of NPIs in reducing RSV transmission. NPIs should be considered significant public health measures to address RSV outbreaks. [ABSTRACT FROM AUTHOR]

Asthma is one of the most common chronic non-communicable diseases worldwide, characterized by variable airflow limitation secondary to airway narrowing, airway wall thickening, and increased mucus resulting from chronic inflammation and airway remodeling. Current epidemiological studies reported that hypovitaminosis D is frequent in patients with asthma and is associated with worsening the disease and that supplementation with vitamin D3 improves asthma symptoms. However, despite several advances in the field, the molecular mechanisms of asthma have yet to be comprehensively understood. MicroRNAs play an important role in controlling several biological processes and their deregulation is implicated in diverse diseases, including asthma. Evidence supports that the dysregulation of miR-21, miR-27b, miR-145, miR-146a, and miR-155 leads to disbalance of Th1/Th2 cells, inflammation, and airway remodeling, resulting in exacerbation of asthma. This review addresses how these molecular mechanisms explain the development of asthma and its exacerbation and how vitamin D3 may modulate these microRNAs to improve asthma symptoms. [ABSTRACT FROM AUTHOR]

The effect of the urease immobilization method was studied on magnetic supports for the Biginelli/Hantzsch reaction. For this purpose, Fe3O4/SiO2 was modified with 3-aminopropyl-triethoxysilane and then activated with glutaraldehyde. A ratio of 500 mg of enzyme per gram of support at 4°C and 18 h were sufficient for the physical adsorption, while 24 h were required for covalent bonding. The Biginelli and Hantzsch reactions were used to evaluate urease application in multicomponent reactions (MCRs). The synthesis of 1,4-dihydropyrimidines was successfully performed using immobilized urease favoring the Hantzsch product. The magnetic properties of the supports allow easy separation, and the urease immobilized by both methods improved the enzymatic activity compared to that of free urease.

The conversion of residual biomass from fruit seeds into biochar can be achieved using MgCl2 as an activating agent and calcining at 700 °C. The resulting MgO‐biochars were employed in the aldol condensation reaction between furfural and acetone. This reaction is essential as the first step in the obtention of biofuels derived from biomass. The biochars were characterized through various physicochemical techniques, revealing that the presence of MgO nanoparticles deposited on the carbon surface modifies the structural and acidic‐basic properties of the carbonaceous materials with a graphitic structure. The biochar with a surface content of MgO of 0.34 % w/w enables the achievement of 100 % of selectivity towards 4‐(2‐furanyl)‐3‐buten‐2‐one (I) with quantitative conversions under optimized conditions. This property highlights the potential of using this type of biochar, commonly used for CO2 capture, as a versatile acidic‐basic catalyst, thereby introducing a novel approach to sustainable chemistry. [ABSTRACT FROM AUTHOR]