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The present study explores the production of microparticulate hydrogels for the selective adsorption of caffeine and mercury in wastewater treatment. Modified glycerol macromonomers, obtained through esterification reactions of glycerol with acrylic acid (n-ACG AA) and methacrylic acid (n-ACG MA), were successfully employed for the synthesis of these versatile materials using inverse suspension polymerization. The impact of different parameters, such as initiator, suspension agents, and monomers concentrations, and reaction time, on the final hydrogel characteristics – including morphology, swelling degree, and reaction yield – was assessed. Ultimately, microparticulate hydrogels (∼110 µm) with distinct absorption capacities were synthesized. Among the hydrogels produced, the n-ACG AA hydrogel exhibited an absorption capacity of 542% (w/w). This hydrogel was synthesized under optimized conditions using n-ACG AA (20 wt%), acrylic acid (50 wt%), bis-acrylamide (30 wt%), and 5% Span-60. The n-ACG MA hydrogel displayed an absorption capacity of 445% (w/w) and was synthesized with n-ACG MA (20 wt%), acrylic acid (50 wt%), bis-acrylamide (30 wt%), and 5% Span-80. Lastly, the hydrogel resulting from the combination of n-ACG AA and sodium acrylate (n-ACG AA/SA) demonstrated the highest absorption of 760% (w/w). It was synthesized with n-ACG AA (20 wt%), sodium acrylate (50 wt%), bis-acrylamide (30 wt%), and 5% Span-60. To evaluate the adsorption capacity of the materials, equilibrium adsorption isotherm assays were performed. The maximum adsorption capacity observed in caffeine assays was 91.55 mg g−1 for the n-ACG AA hydrogel. In mercury assays, the best capacity was found to be 369.75 mg g−1 with the hydrogel synthesized using n-ACG AA macromonomer combined with sodium acrylate. For both adsorbates, the Freündlich model was proven to be the most suitable for describing the adsorption isotherms. These results reveal the potential application of modified glycerol-based hydrogels in wastewater treatment processes. [Display omitted] • Modified glycerol-based hydrogels show promising potential for water treatment. • Hydrogels exhibited a remarkable absorption capacity, reaching up to 760%. • Hydrogels demonstrated high performance in removing caffeine and mercury from water. • Remarkable adsorption capacity for caffeine (92 mg g−1) and mercury (386 mg g−1). [ABSTRACT FROM AUTHOR]

The present work addresses the synthesis and characterization of a new bio-nanocomposite based on acrylated fatty acids (AFA) derived from castor oil, ethyl acrylate and AFA surface modified γ-Fe 2 O 3 (γ-Fe 2 O 3 @AFA) magnetic nanoparticles (MNPs). It was shown that the in situ formed bio-nanocomposite containing around 2.0 wt.% of γ-Fe 2 O 3 MNPs with average particle size of ca. 9.0 nm, as determined by XRD and TEM measurements, displayed good magnetic response and superparamagnetic behavior. The magnetization measurements indicated that the incorporation of γ-Fe 2 O 3 @AFA MNPs into the poly(ethyl acrylate- co -AFA) matrix did not affect the magnetization saturation, remanence and coercivity of the MNPs, preserving the magnetic properties of the γ-Fe 2 O 3 precursor. Additionally, the use of AFA to chemically modify the surface of MNPs opens a new scenario on the chemical modification of MNPs with agents that undergo free-radical reactions, allowing for the proper dispersion of MNPs into the thermoplastic polymer matrices and minimizes the undesired leaching of the MNPs. [ABSTRACT FROM AUTHOR]

Dual-motor battery electric vehicles (DM-BEVs) are a trending technology in the electric vehicle market. They have the potential to achieve higher energy savings and dynamic performances compared to single-speed, single-motor BEVs. However, a more complex and robust energy management system (EMS) is needed to achieve these benefits. Hence, this work reviews the design process and real-time implementation of EMSs tailored for DM-BEVs, starting from the fundamental concepts of two-motor coupling. The advantages and disadvantages of the most popular dual-motor architectures and their influence on the EMS design complexity are presented, followed by a revision of the reported energy management controllers. Besides the most prominent methods, classified as rule-based or optimization-based techniques, reinforcement learning-based EMSs are discussed in detail, given their near-optimal, real-time implementation and adaptability to newer, unforeseen drive cycles. Finally, the standard procedures and equipment required to assess the EMS' performance with hardware-in-the-loop tests are presented. Conclusions and open challenges for the energy management controllers of DM-BEVs are discussed at the end of this work. [Display omitted] • The energy management design for dual-motor battery electric vehicles is explained. • Dual-motor architectures' influence on energy management complexity is discussed. • Existing and trending control approaches are presented. • The controller's migration for HIL and in-vehicle tests are explained. • Challenges and opportunities for dual-motor battery electric vehicles are listed. [ABSTRACT FROM AUTHOR]

The trypanosome life cycle consists of a series of developmental forms each adapted to an environment in the relevant insect and/or mammalian host. The differentiation process from the mammalian bloodstream form to the insect-midgut procyclic form in Trypanosoma brucei occurs in two steps in vivo . First proliferating ‘slender' bloodstream forms differentiate to non-dividing ‘stumpy' forms arrested in G1. Second, in response to environmental cues, stumpy bloodstream forms re-enter the cell cycle and start to proliferate as procyclic forms after a lag during which both cell morphology and gene expression are modified. Nearly all arrested cells have lower rates of protein synthesis when compared to the proliferating equivalent. In eukaryotes, one mechanism used to regulate the overall rate of protein synthesis involves phosphorylation of the alpha subunit of initiation factor eIF2 (eIF2α). The effect of eIF2α phosphorylation is to prevent the action of eIF2B, the guanine nucleotide exchange factor that activates eIF2 for the next rounds of initiation. To investigate the role of the phosphorylation of eIF2α in the life cycle of T. brucei , a cell line was made with a single eIF2α gene that contained the phosphorylation site, threonine 169, mutated to alanine. These cells were capable of differentiating from proliferating bloodstream form cells into arrested stumpy forms in mice and into procyclic forms in vitro and in tsetse flies. These results indicate that translation attenuation mediated by the phosphorylation of eIF2α on threonine 169 is not necessary for the cell cycle arrest associated with these differentiation processes. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel electrochemical sensor for dopamine detection was successfully developed. • The IL terpolymer/iron oxide/MWCNT electrode displayed a great synergistic response. • Dopamine was detected in the presence of a 25-fold excess of ascorbic acid. • After 80 runs TS-MAG-MWCNT electrode showed only an 8% reduction in its sensitivity. • Sensor response is not affected by the matrix composition or other interferents. In this study, we introduce a novel electrochemical sensor for dopamine (DA) detection utilizing an ionic liquid-based terpolymer/iron oxide/multiwalled carbon nanotube (TS-MAG-MWCNT) nanocomposite electrode. The synergistic combination of improved surface adhesion, electrocatalytic activity, and electron conductivity of each individual material enables the determination of DA in the presence of a 25-fold excess of AA (ascorbic acid). The electrode, operated by square wave voltammetry, allows the detection of DA within a wide linear working range from 1 µmol/L to 200 µmol/L, with a limit of detection of 63 nmol/L. A single TS-MAG-MWCNT electrode can be used for more than 80 consecutive runs, with only an 8 % reduction in its sensitivity. Additionally, the response of electrodes fabricated in different batches varies by only 5 %. The sensor's response is not affected by the matrix composition or other interferents, as demonstrated by experiments conducted in synthetic urine. [ABSTRACT FROM AUTHOR]

For the first time, it was shown the cationic miniemulsion polymerization of styrene using an ionic liquid as catalyst. The ionic liquid (BMI·Fe 2 Cl 7 ) was tolerant to the presence of high amount of water, being effective for polymerization of styrene in the evaluated temperatures range from 70 to 90 °C. The polymerization was considerably slower than conventional cationic polymerization, indicating that this process is easier to control than the conventional ones. In addition, quite high molecular weights were reached, while the particle size, between 150 and 175 nm, was within the typical range for miniemulsion polymerization. [ABSTRACT FROM AUTHOR]

This work presents experimental results on the synthesis of soybean oil-based polymers through emulsion polymerization process. It was shown that polymeric materials can be successfully synthesized with high monomers conversion close to 100% and very high stability, displaying relatively high shelf-life time. Polymeric nanoparticles showing narrow particle size distribution, with average diameter around 80 nm (PdI = 0.213), determined via dynamic light scattering measurements were obtained. It was also observed by calorimetric analysis, that the final polymeric material presents two exothermic transitions and two glass transition temperatures. This complex thermal behavior probably takes place due to the nature of the monomeric mixture (AFFAM—acrylated linolenic, linoleic, and oleic acids in combination with methyl methacrylate), indicating that the final polymer presents a complex macromolecular arrangement. The glass transition temperature of the polymer lattices was reduced because of the AFFAM incorporation into the growing polymer chains, and additionally the thermal stability was improved. Regarding the average molar masses, it was observed that AFFAM comonomer plays an important role, leading to a decreasing in the mass-average molar mass when the AFFAM concentration is increased in the reaction medium. Depending on the AFFAM amount, the mass-average molar masses were found within the range from 70,000 g mol −1 to 890,000 g mol −1 with molar-mass dispersity lying in the interval from 1.7 to 2.4. [ABSTRACT FROM AUTHOR]

Enzymatically synthesised poly(glycerol adipate) (PGA) has shown a palette of key desirable properties required for a biomaterial to be considered a 'versatile polymeric tool' in the field of drug delivery. PGA and its variations can self-assemble into nanoparticles (NPs) and interact at different levels with small active molecules. PGA derivatives are usually obtained by functionalising the glyceryl side hydroxyl group present along the main polymer scaffold. However, if the synthetic pathways are not finely tuned, the self-assembling ability of these new polymeric modifications might be hampered by the poor amphiphilic balance. For this reason, we have designed a straightforward one-pot synthetic modification, using a small library of diols in combination with glycerol, aimed at altering the backbone of the polymer without affecting the hydrophilic glyceryl portion. The diols introduce additional functionality into the backbone of PGA alongside the secondary hydroxyl group already present. We have investigated how extra functionalities along the polymer backbone alter the final polymer reactivity as well the chemical and biological properties of the nanoparticles. In addition, with the intent to further improve the green credentials of the enzymatic synthesis, a solvent derived from renewable resources, (2-methyl tetrahydrofuran, 2-MeTHF) was employed for the synthesis of all the PGA-variants as a replacement for the more traditionally used and fossil-based tetrahydrofuran (THF). In vitro assays carried out to evaluate the potential of these novel materials for drug delivery applications demonstrated very low cytotoxicity characteristic against NIH 3T3 model cell line. [Display omitted] • Poly(glycerol adipate) (PGA) one-pot synthetic alteration using a series of diols. • Direct modification of the PGA backbone without affecting the glyceryl portion. • The diols used have introduced additional functionality into the backbone. • A renewably sourced solvent, (2-MeTHF) was employed for the polymer synthesis. [ABSTRACT FROM AUTHOR]