Accessible Eco-Friendly Method for Wastewater Removal of the Azo Dye Reactive Black 5 by Reusable Protonated Chitosan-Deep Eutectic Solvent Beads.

A novel approach to enhance the utilization of low-cost and sustainable chitosan for wastewater remediation is presented in this investigation. The study centers around the modification of chitosan beads using a deep eutectic solvent composed of choline chloride and urea at a molar ratio of 1:2, followed by treatment with sulfuric acid using an impregnation accessible methodology. The effectiveness of the modified chitosan beads as an adsorbent was evaluated by studying the removal of the azo dye Reactive Black 5 (RB5) from aqueous solutions. Remarkably, the modified chitosan beads demonstrated a substantial increase in adsorption efficiency, achieving excellent removal of RB5 within the concentration range of 25-250 mg/L, ultimately leading to complete elimination. Several key parameters influencing the adsorption process were investigated, including initial RB5 concentration, adsorbent dosage, contact time, temperature, and pH. Quantitative analysis revealed that the pseudo-second-order kinetic model provided the best fit for the experimental data at lower dye concentrations, while the intraparticle diffusion model showed superior performance at higher RB5 concentration ranges (150-250 mg/L). The experimental data were successfully explained by the Langmuir isotherm model, and the maximum adsorption capacities were found to be 116.78 mg/g at 298 K and 379.90 mg/g at 318 K. Desorption studies demonstrated that approximately 41.7% of the dye could be successfully desorbed in a single cycle. Moreover, the regenerated adsorbent exhibited highly efficient RB5 removal (80.0-87.6%) for at least five consecutive uses. The outstanding adsorption properties of the modified chitosan beads can be attributed to the increased porosity, surface area, and swelling behavior resulting from the acidic treatment in combination with the DES modification. These findings establish the modified chitosan beads as a stable, versatile, and reusable eco-friendly adsorbent with high potential for industrial implementation.

Thirty-three vascular residency programs among 13 countries joining forces to improve surgical education in times of COVID-19: A survey-based assessment.

BACKGROUND: Academic interaction with mentors has almost become minimal due to the current pandemic of COVID-19. The objective of this study is to introduce how a group of vascular surgery residencies joined forces to improve surgical education in times of COVID-19. METHODS: On May 2020, a group of Hispanic American vascular residency programs created webinar sessions of arterial and venous clinical cases among vascular residents across Latin America and Europe. Participants were surveyed via email. Questions were about the perceived quality and utility of the webinars; answers were stratified into negative (disagree), neutral, and positive (agree). RESULTS: There have been 60 sessions and 118 clinical cases presented. The survey was answered by 106 participants, 82 males (78.8%) and 24 women (23.0%). Fifty-four (51.9%) were board-certified vascular surgeons, 49 (47.1%) vascular surgery residents, and 2 (1.9%) general surgery residents. Mean age of the participants was 41.5 years (range: 25-74 years). Mean years of vascular surgery practice or experience were 11.2 years (range: 0-45 years). The residency programs involved in this project were from 13 different countries. Most answers received were positive for both perceived quality and utility of the webinars. CONCLUSION: Globalization and technology provide an opportunity for international education, with the goal of building well-rounded and academic vascular surgeons. This group is just the beginning of a large collaborative group among Hispanic American countries, hoping that more residency programs will join, with the aim of breaking borders in the education of vascular surgery.

Thermal Analysis of Binary Mixtures of Imidazolium, Pyridinium, Pyrrolidinium, and Piperidinium Ionic Liquids.

Ionic liquids (ILs) are being widely studied due to their unique properties, which make them potential candidates for conventional solvents. To study whether binary mixtures of pure ionic liquids provide a viable alternative to pure ionic liquids for different applications, in this work, the thermal analysis and molar heat capacities of five equimolar binary mixtures of ionic liquids based on imidazolium, pyridinium, pyrrolidinium, and piperidinium cations with dicyanamide, trifluoromethanesulfonate, and bis(trifluoromethylsulfonyl)imide anions have been performed. Furthermore, two pure ionic liquids based on piperidinium cation have been thermally characterized and the heat capacity of one of them has been measured. The determination and evaluation of both the transition temperatures and the molar heat capacities was carried out using differential scanning calorimetry (DSC). It was observed that the thermal behavior of the mixtures was completely different than the thermal behavior of the pure ionic liquids present, while the molar heat capacities of the binary mixtures were very similar to the value of the average of molar heat capacities of the two pure ionic liquids.

Liquid-liquid extraction of phenolic compounds from water using ionic liquids: Literature review and new experimental data using [C2mim]FSI.

In this work, the capability of the ionic liquid, 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide, [C2mim]FSI, to extract o-cresol, 2-chlorophenol, resorcinol and phenol from water, reaching the legal limit of 1 mg L-1 was analyzed. The extraction process was carried out for each one of these phenolic compounds varying the initial concentration in water from 3 mg L-1 to 1000 mg L-1, and for aqueous mixtures of the four phenolic compounds in the same concentration range. Because of the scarcity of physical properties of the [C2mim]FSI, density, speed of sound, dynamic viscosity and refractive index were measured from 293.15 to 343.15 K at atmospheric pressure. From the experimental data, the thermal expansion coefficient and the isentropic compressibility for the pure ionic liquid were calculated. Even though [C2mim]FSI is hydrophobic, it can solve small quantities of water that can hinder the recovery of the ionic liquid, consequently the solubility of water in the ionic liquid was determined at several temperatures and atmospheric pressure. In addition to experimental data, a literature review on the use of ionic liquids to extract phenolic compounds from water was performed.

Statins upregulate CD36 expression in human monocytes, an effect strengthened when combined with PPAR-gamma ligands Putative contribution of Rho GTPases in statin-induced CD36 expression.

Scavenger receptor CD36 plays important roles in atherosclerosis, inflammation, thrombosis, and angiogenesis. Statins besides lowering serum cholesterol levels, exhibit a variety of effects on inflammation, coagulation and atherosclerosis lesion stability. PPAR-gamma ligands influence macrophage responses to many inflammatory stimuli. Herein, we investigated in human monocytes the effect of statins alone, and in combination with PPAR-gamma ligands on CD36 expression, as well as the molecular mechanisms underlying the regulatory action of statins. Our results demonstrate that statins upregulate both CD36 surface protein and mRNA by potentiating the transcription of the CD36 gene. Furthermore, the combination of statins and PPAR-gamma ligands has an additive effect on CD36 expression. Effects of statins on CD36 expression were prevented by mevalonate and geranylgeraniol, indicating the requirement of geranylgeranylated proteins for CD36 regulation. Rho GTPases inhibitor C3 exoenzyme reproduced the effect of statins, while Rho activator lysophosphatidic acid downregulated CD36. Transient expression of dominant-negative mutants of RhoA and RhoB induced a significant increased in CD36 promoter activity. Finally, the actin cytoskeleton disrupter cytochalasin D upregulated CD36. These data indicate that Rho proteins are important modulators of CD36 expression, and strongly suggest that statins increased CD36 expression by disrupting cytoskeleton organization by inactivating Rho GTPases. These features prompt to investigate the roles of Rho GTPases and actin cytoskeleton modulators on monocytic functions affected by statins.

Remoción de estireno por phanerochaete chrysosporium: en cultivo líquido / Styrene removal by phanerochaete chrysosporium: in liquid culture

El objetivo de este trabajo fue demostrar si un hongo ligninolítico, Phanerochaete chrysosporium, podría tener la capacidad de 1) tolerar altas concentraciones de estireno y 2) remover el estireno en un cultivo líquido. Los resultados mostraron que el hongo fue capaz de crecer a concentraciones de estireno bajas (200mg/l) y relativamente altas (1500mg/l). se mostró que 40 y 46 por ciento de estireno fue biodegradado, respectivamente, en 35 días. Sin embargo, 30 y 53 por ciento, fue removido por volatilización. La detección de la actividad enzimatica de lignina peroxidasa en el cultivo del hongo con estireno a las dos concentraciones, quizas implique su participación en la biodegradación de este compuesto. El ácido benzóico fue detectado en el cultivo como producto de la biodegradación