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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]

Iron-containing imidazolium-based ionic liquids were successfully applied as catalysts in the styrene polymerization. Solventless conditions, organic solvents and different imidazolium-based ionic liquid catalysts were tested to evaluate the best reaction conditions. The ionic liquids BMI.FeCl 4 and BMI.Fe 2 Cl 7 showed very distinct catalytic activities. Schulz–Flory distributions indicate two or three active catalytic species in different distributions. Via on-line direct infusion electrospray (tandem) mass spectrometry (ESI-MS(/MS)) reaction monitoring, both active catalytic species in accordance with the Schulz–Flory distributions were intercepted and characterized, providing important mechanistic insights that allowed us to propose a rationale for the origin of the superior catalytic efficiency. [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]

Graphical abstract A biobased monomer acrylated ricinoleic acid was synthesized from castor oil and copolymerized with methyl methacrylate in miniemulsion forming polymeric nanoparticles. The addition of the biobased monomer led to a decrease in the glass transition temperature of the copolymer and to the formation of a small fraction of gel, resulting in materials with interesting properties for future applications. Highlights • A biobased monomer acrylated ricinoleic acid was synthesized from castor oil. • The biobased monomer was copolymerized with methyl methacrylate in miniemulsion forming polymeric nanoparticles. • Polymers with lower Tgs were obtained with the addition of the biobased monomer. • The copolymers exhibited interesting properties for future applications as adhesives. Abstract Vegetable oils-based polymers are promising materials with application in the industry of coatings and adhesives. Chemically-modified ricinoleic acid obtained from castor oil was used in this study to produce polymeric materials. The adopted strategy consisted in the epoxidation of the double bonds of ricinoleic acid, followed by the ring opening reaction in the presence of acrylic acid to form the acrylated ricinoleic acid (ARA). Free radical copolymerizations of ARA and methyl methacrylate (MMA) were carried out in miniemulsion, resulting in latexes stable over a long storage time. DLS measurements revealed the formation of submicron polymeric particles of different sizes strongly dependent on the fraction of the biobased monomer ARA, exhibiting diameters ranging from approximately 80 nm to 150 nm, as the ARA fraction was increased up to 80 wt%. It was possible to prepare polymers with broad ranges of mass-average molar masses in the range from 1137 kDa to 65 kDa and glass transition temperatures lying in the interval from approximately 124 °C–50 °C by varying the concentration of the comonomer ARA. Crosslinked copolymers were obtained by increasing the proportion of ARA. [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]

This work presents an experimental study focusing on the preparation and characterization of modified green clay with quaternary ammonium salts alkyl dimethyl benzyl ammonium chloride (ADMBAC) and distearyl dimethyl ammonium chloride (DSDMAC) intended to be used as adsorbent in the process of removing oil emulsion in an oil–water system using finite bath. X-ray diffraction (XRD), infrared spectroscopy (IR) and expansion test (adsorption capacity and Foster swelling) measurements were performed in order to evaluate the performance of the ion exchange reactions and the degree of affinity with oil products. There was an increase in the XRD basal spacing of the modified clays (1.96 nm and 2.25 nm for DSDMAC and ADMBAC salts, respectively) in comparison to the observed value (1.56 nm) for the unmodified clay. The IR results revealed that salts were successfully incorporated to clay structure. Based on the expansion tests the organoclays presented the best efficiency of separation, independent on the kind of solvent used in comparison with the unmodified clay performance. The modified clays exhibit a very high capacity of adsorption. The predictions of multiple linear regression models determined based on the factorial design of experiments are excellent. [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]

• Gold nanoparticles functionalized with a novel poly(ionic liquid). • The poly(ionic liquid) replaces citrate ions and provides for better colloidal stability of the gold nanoparticles. • Gold nanoparticles-poly(ionic liquid) layer-by-layer assembled nanocomposite enhances the electrocatalytic activity of ITO electrode towards triclosan electro oxidation. • Triclosan is detected at very low concentrations at both tooth paste and lake water samples. • The voltammetric method based on gold nanoparticles-poly(ionic liquid) nanocomposite electrode is insensitive to the matrix effect. Triclosan (TCS), a powerful bactericide agent found in personal care products, has been recently recognized as a contaminant of emerging concern, with endocrine disrupting chemical activity, and whose detection in environmental, biological and/or PCP samples is of great concern nowadays. Therefore, this contribution describes indium-doped tin oxide (ITO) substrates modified with Au nanoparticle-poly(ionic liquid) (Au-PIL) nanocomposite films for the voltammetric detection of TCS in lake water and toothpaste samples. The electroanalytical performance evaluated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV), shows the modified electrode oxidizes TCS at much higher oxidation currents than bare ITO. At optimized conditions, the analytical method is linear (R2 > 0.99) in the selected working range (10–60 µmol L−1), presents a sensitivity of 57.1 µA cm−2/mol L−1•and a limit of detection of 0.098 µmol L−1 (28.3 µg L−1). TCS determinations are successfully carried out in spiked lake water samples showing that the electrode response is not affected by such a complex matrix. The concentration of TCS found in a commercial brand toothpaste, simultaneously determined by voltammetry and HPLC, is similar (95% confidence level, t -test) between both techniques and comparable to that described in the product package. [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]

Nanoparticles of iron oxide play an important role on the field of nanotechnology and nanoscience presenting tremendous potential for various applications. Oleic acid has been shown to be a promising coating material, allowing to obtain monodisperse, uniform and stable nanoparticles. However, for certain applications which utilize the encapsulation of magnetic nanoparticles into polymer matrices it becomes necessary to use coating materials which exhibit functional groups in their structure capable of avoiding leaching problems. To this end, the present study aimed to develop magnetite nanoparticles coated with chemically modified oleic acid. The reactive functional group present in the fatty acid molecule can promote polymerization between the monomer species and the coating material with high encapsulation efficiency. The different steps of the reactions to obtain acrylated oleic acid were evaluated by Fourier transform infrared (FTIR) spectroscopy and 1 H nuclear magnetic resonance spectroscopy. The coated nanoparticles were characterized by FTIR, thermogravimetric analysis, X-ray diffraction, transmission electron microscopy, Mössbauer spectroscopy, Raman spectroscopy and magnetization measurements. The coated nanoparticles showed high dispersibility with a uniform average size of 9.5 nm, saturation magnetization of 61.2 emu/g and superparamagnetic behavior, which make it a very promising for the formation of nanocomposites. [ABSTRACT FROM AUTHOR]

The present work addresses the use of Raman spectroscopy and multivariate curve resolution–alternating least squares (MCR-ALS) for the evaluation of the reaction conversion in copolymerization of aluminum (III) methacrylate and vinyl monomers (vinyl acetate, ethyl acrylate and methyl methacrylate). For the synthesis of these materials, pseudo-dispersion copolymerizations were carried out in a reaction medium containing 17 wt.% of aluminum (III) methacrylate [Al(III)MA] and 83 wt.% of vinyl monomers, such as vinyl acetate (VAc), ethyl acrylate (EA) and methyl methacrylate (MMA). Raman spectra were acquired at different reaction times for each monomer used. We used multivariate curve resolution (MCR-ALS) in order to evaluate the reaction conversion and the concentration profiles. The concentration profile of VAc/Al(III)MA reaction shows that the polymerization occurs slowly, in which the conversion stabilizes after 15 h of reaction. The concentration profile of EA/Al(III)MA copolymerization shows that high conversions are achieved in a short reaction time. However, as the reaction proceeds (between 4 and 12 h), it is possible to observe a decrease of the reaction rate, which is an indication that the modified monomer is polymerizing. The concentration profile of MMA/Al(III)MA copolymerization shows a high conversion in the first 2 h of reaction, indicating a possible low incorporation of the modified metal monomer into the growing copolymer chains, due to the differences of reactivity between the monomer species. The use of Raman spectroscopy coupled with MCR-ALS allowed for the evaluation of the conversion rate of three different organic–inorganic copolymers, although it is difficult to determine the conversion of hybrid polymers, the use of chemometric methods and Raman spectroscopy allowed us to compare the conversion rate between the studied copolymers. [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]