Added-value chemicals from lignin oxidation

Lignin is the second most abundant component, next to cellulose, in lignocellulosic biomass. Large amounts of this polymer are produced annually in the pulp and paper industries as a coproduct from the cooking process-most of it burned as fuel for energy. Strategies regarding lignin valorization have attracted significant attention over the recent decades due to lignin’s aromatic structure. Oxidative depolymerization allows converting lignin into added-value compounds, as phenolic monomers and/or dicarboxylic acids, which could be an excellent alternative to aromatic petrochemicals. However, the major challenge is to enhance the reactivity and selectivity of the lignin structure towards depolymerization and prevent condensation reactions. This review includes a comprehensive overview of the main contributions of lignin valorization through oxidative depolymerization to produce added-value compounds (vanillin and syringaldehyde) that have been developed over the recent decades in the LSRE group. An evaluation of the valuable products obtained from oxidation in an alkaline medium with oxygen of lignins and liquors from different sources and delignification processes is also provided. A review of C4 dicarboxylic acids obtained from lignin oxidation is also included, emphasizing catalytic conversion by O2 or H2O2 oxidation.This work was financially supported by Base Funding—UIDB/50020/2020 and Programmatic- UIDP/50020/2020 Funding of the Associate Laboratory LSRE-LCM—funded by national funds through FCT/MCTES (PIDDAC) and Base Funding—UIDB/00690/2020 of CIMO— Centro de Investigação de Montanha—funded by national funds through FCT/MCTES (PIDDAC). COST Action LignoCOST (CA17128). Carlos Vega-Aguilar thanks the Costa Rican Science, Technology and Telecommunications Ministry for the PhD. Scholarship MICITT-PINN-CON-2-1-4-17-1-002.info:eu-repo/semantics/publishedVersio

Microwave-assisted lignin wet peroxide oxidation to C4 dicarboxylic acids

Innovative methodologies, such as microwaveassisted reaction, can help to valorize lignin with higher productivity and better energy efficiency. In this work, microwave heating was tested in the wet peroxide oxidation of three lignins (Indulin AT, Lignol, and Eucalyptus globulus lignins) as a novel methodology to obtain C4 dicarboxylic acids. The effect of temperature, time, and catalyst type (TS-1 or Fe-TS1) was evaluated in the production of these acids. The TS-1 catalyst improved succinic acid yield, achieving up to 9.4 wt % for Lignol lignin. Moreover, the microwave heating specifically enhanced Lignol conversion to malic acid (34 wt %), even without catalyst, showing to be an attractive path for the future valorization of organosolv lignins. Overall, compared to conventional heating, microwave heating originated a rapid lignin conversion. Nevertheless, for prolonged times, conventional heating led to better results for some target products, e.g., malic and succinic acids.This work was financially supported by Base Funding UIDB/50020/2020 of the Associate Laboratory LSRE-LCM funded by national funds through FCT/MCTES (PIDDAC); Base Funding UIDB/00690/2020 of CIMO-Centro de Investigação de Montanha funded by national funds through FCT/MCTES (PIDDAC). COST Action LignoCOST (CA17128). C.A.V.-A. thanks the Costa Rican Science, Technology and Telecommunications Ministry for the Ph.D. Scholarship MICITT-PINN-CON-2-1-4-17-1-002. The authors thank Dr. Maria José Sampaio and Prof. Dr. Joaquim Faria (LA LSRE-LCM) for the help with the FTIR measurements.info:eu-repo/semantics/publishedVersio

Reactivation of hepatitis B virus infection during treatment of hepatitis C with direct-acting antivirals

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Noncanonical electromechanical coupling paths in cardiac hERG potassium channel

Voltage-gated potassium channels are involved in many physiological processes such as nerve impulse transmission, the heartbeat, and muscle contraction. However, for many of them the molecular determinants of the gating mechanism remain elusive. Here, using a combination of theoretical and experimental approaches, we address this problem focusing on the cardiac hERG potassium channel. Network analysis of molecular dynamics trajectories reveals the presence of a kinematic chain of residues that couples the voltage sensor domain to the pore domain and involves the S4/S1 and S1/S5 subunit interfaces. Mutagenesis experiments confirm the role of these residues and interfaces in the activation and inactivation mechanisms. Our findings demonstrate the presence of an electromechanical transduction path crucial for the non-domain-swapped hERG channel gating that resembles the noncanonical path identified in domain-swapped K+ channels

Effects of wet CO oxidation on the operation of engines and power generators

A simplified method is used to determine the optimum water content in the flue gases of charcoal gasifiers to be utilized as alternative fuels in the operation of engines and gas turbines for power generation. Computational models of plug flow reactors and well stirred reactors are employed to simulate the reaction and post-flame zones, adopting different chemical mechanisms. In the simulations reactants enter the reactors at 1000 K, 1 atm and equivalence ratio 0.25. It was observed that mixtures about 3% to 4% in volume of water vapor allow to obtain optimal operation characteristics, including high blowout limit, low ignition delay, maximum reaction zone temperature, high CO2 prodution and low thermal NO formation. It was observed that increasing water contents reduce significantly ignition times up to 3% in volume, while blowout mass flow rates increase continuously up to 6 % in volume, the maximum value considered. Formation of NO decreases continuously with humidity after the flame zone, while there are peaks of NO formation within the flame zone below 1% in volume. Higher water vapor content decreases the final temperatures below 1700 K, leading to a lower thermal efficiency. The method can be used to estimate optimum operational conditions with other input parameters

Remodeling of the m6A RNA landscape in the conversion of acute lymphoblastic leukemia cells to macrophages

We thank CERCA Programme/Generalitat de Catalunya for institutional support. This work was supported by the Health Department PERIS-project no. SLT/002/16/00374 and AGAUR-projects no. 2017SGR1080 of the Catalan Government (Generalitat de Catalunya); Ministerio de Ciencia e Innovación (MCI), Agencia Estatal de Investigación (AEI) and European Regional Development Fund (ERDF) project no. RTI2018-094049-B-I00; the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (Grant agreement No. 743168); the Varda and Boaz Dotan Research Center in Hemato-oncology affiliated to the Tel Aviv University; the Cellex Foundation; and “la Caixa” Banking Foundation (LCF/PR/GN18/51140001). ME is an ICREA Research Professor.Peer Reviewed"Article signat per 12 autors/es: Alberto Bueno-Costa, David Piñeyro, Carlos A. García-Prieto, Vanessa Ortiz-Barahona, Laura Martinez-Verbo, Natalie A. Webster, Byron Andrews, Nitzan Kol, Chen Avrahami, Sharon Moshitch-Moshkovitz, Gideon Rechavi & Manel Esteller"Postprint (published version

Reutilização de águas residuais : modelação da adsorção de nutrientes no solo

O presente estudo incide na modelação da remoção de nutrientes presentes em águas residuais domésticas por adsorção no solo e na avaliação do risco de contaminação de aquíferos por parte destes. Nesse sentido, desenvolveu-se um modelo matemático e efectuou-se a determinação experimental dos parâmetros que caracterizam as isotérmicas de adsorção dos iões nitrato, fosfato e amónio. Os resultados experimentais indicaram que o solo tem principalmente carga iónica positiva, visto que os iões de carga contrária (tais como o nitrato e fosfato) foram os que principalmente adsorveram. Os resultados da simulação demonstraram que o fosfato é totalmente adsorvido e que a concentração de nitrato e amónio na água intersticial, após o período de um ano, é de 0.250 mg/L e 0.023 mg/L respectivamente, a 2 m de profundidade. Em relação ao exercício de simulação, estudouse o efeito de uma sobrecarga de nutrientes assim como a possibilidade de ocorrer saturação da coluna de solo. No caso de ocorrer uma sobrecarga de nutrientes no solo proveniente da descarga de água residual com uma concentração até quatro vezes superior ao valor médio, verificou-se que a concentração do ião amónio foi a mais afectada, aumentando de 27 % a uma profundidade de 2 m e ao fim de um ano. Finalmente, os parâmetros das isotérmicas de adsorção (segundo os modelos de Freundlich e Langmuir) foram sujeitos a uma análise de sensibilidade, tendo-se comprovado que o modelo desenvolvido é extremamente sensível à constante α da isotérmica de Freundlich

The role of automatic shape and position recognitionin streamlining manufacturing

The main features of most components consist of simple basic functional geometries: planes, cylinders, spheres and cones. Shape and position recognition of these geometries is essential for dimensional characterization of components, and represent an important contribution in the life cycle of the product, concerning in particular the manufacturing and inspection processes of the final product. This work aims to establish an algorithm to automatically recognize such geometries, without operator intervention. Using differential geometry large volumes of data can be treated and the basic functional geometries to be dealt recognized. The original data can be obtained by rapid acquisition methods, such as 3D survey or photography, and then converted into Cartesian coordinates. The satisfaction of intrinsic decision conditions allows different geometries to be fast identified, without operator intervention. Since inspection is generally a time consuming task, this method reduces operator intervention in the process. The algorithm was first tested using geometric data generated in MATLAB and then through a set of data points acquired by measuring with a coordinate measuring machine and a 3D scan on real physical surfaces. Comparison time spent in measuring is presented to show the advantage of the method. The results validated the suitability and potential of the algorithm hereby proposedCMAT, the Research Centre of Mathematics of the University of Minho with the Portuguese Funds from the “Fundação para a Ciência e a Tecnologia”, through the Project PEstOE/MAT/UI0013/2014; MEtRICs – (Mechanical Engineering and Resource Sustainability Center); CGIT - Centro de Gestão Industrial e da Tecnologi

EmIR: An emotional intelligent robot assistant

The development of robots that are truly sociable requires understanding how human interactions can be applied to the interaction between humans and robots. A sociable robot must be able to interact with people taking into account aspects like verbal and non-verbal communications (emotions, postures, gestures). This work presents a social robot which main goal is to provide assistance to older people in carrying out their daily activities (through suggestions or reminders). In addition, the robot presents non-verbal communications like perceiving emotions and displaying human identifiable emotions in order to express empathy. A prototype of the robot is being tested in a daycare centre in the northern area of Portugal.This work is partially supported by the MINECO/FEDER TIN2015-65515-C4- 1-R and the FPI grant AP2013-01276 awarded to Jaime-Andres Rincon. Angelo Costa thanks the FCT - Fundacao para a Ciencia e Tecnologia for the PostDoc grant SFRH/BPD/102696/2014. This work is supported by FCT within the projects UID/CEC/00319/2013 and COMPETE: POCI-01-0145-FEDER007043

A single mutation in cyclodextrin glycosyltransferase from Paenibacillus barengoltzii changes cyclodextrin and maltooligosaccharides production

Cyclodextrin glycosyltransferases (CGTases) are bacterial enzymes that catalyze starch conversion into cyclodextrins, which have several biotechnological applications including solubilization of hydrophobic compounds, masking of unpleasant odors and flavors in pharmaceutical preparations, and removal of cholesterol from food. Additionally, CGTases produce maltooligosaccharides, which are linear molecules with potential benefits for human health. Current research efforts are concentrated in the development of engineered enzymes with improved yield and/or particular product specificity. In this work, we analyzed the role of four residues of the CGTase from Paenibacillus barengoltzii as determinants of product specificity. Single mutations were introduced in the CGTase-encoding gene to obtain mutants A137V, A144V, L280A and M329I and the activity of recombinant proteins was evaluated. The residue at position 137 proved to be relevant for CGTase activity. Molecular dynamics studies demonstrated additionally that mutation A137V produces a perturbation in the catalytic site of the CGTase, which correlates with a 10-fold reduction in its catalytic efficiency. Moreover, this mutant showed increased production of maltooligosaccharides with a high degree of polymerization, mostly maltopentaose to maltoheptaose. Our results highlight the role of residue 137 as a determinant of product specificity in this CGTase and may be applied to the rational design of saccharide-producing enzymes.Fil: Castillo, Julieta de Las Mercedes. Universidad Nacional de Luján. Departamento de Ciencias Básicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Caminata Landriel, Soledad. Universidad Nacional de Luján. Departamento de Ciencias Básicas; ArgentinaFil: Sànchez Costa, M.. Centro de Biología Molecular "Severo Ochoa"; EspañaFil: Taboga, Oscar Alberto. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Berenguer, J.. Centro de Biología Molecular "Severo Ochoa"; EspañaFil: Hidalgo, A.. Centro de Biología Molecular "Severo Ochoa"; EspañaFil: Ferrarotti, Susana Alicia. Universidad Nacional de Luján. Departamento de Ciencias Básicas; ArgentinaFil: Costa, Hernán. Universidad Nacional de Luján. Departamento de Ciencias Básicas; Argentina. Universidad Nacional de Luján. Instituto de Ecología y Desarrollo Sustentable. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ecología y Desarrollo Sustentable; Argentin