326 research outputs found

    Enzymatic hydrolysis of brewer’s spent grain to obtain fermentable sugars

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    Lignocellulosic biomass is a feedstock with the potential to be converted into value-added bioproducts. The use of enzymatic hydrolysis allows the cleavage of lignocellulose into their monomeric units, but there are some drawbacks that make its use in industrial biocatalysis unfeasible. In the present study, we describe the hydrolysis of brewer’s spent grain (BSG) with an enzymatic cocktail produced by Aspergillus niger CECT 2700 and its comparison with commercial enzymes. In addition, it was determined whether pretreating the BSG (non-pressurized alkaline hydrolysis or treatment with cholinium glycinate ionic liquid) is necessary. Results show that both pretreatments enhanced xylose release (10.55±0.07g/L and 8.14±0.13g/L respectively), meanwhile the hydrolysis of raw BSG with the enzymatic cocktail produced solutions containing high levels of glucose (18.45±1.66g/L) and xylose (6.38±0.26g/L).Ministerio de Economía y Competitividad | Ref. CTQ2015-71436-C2-1-

    Cellular automaton model for the simulation of laser dynamics

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    The classical modeling approach for laser study relies on the differential equations. In this paper, a cellular automaton model is proposed as an alternative for the simulation of population dynamics. Even though the model is simplified it captures the essence of laser phenomenology: (i) there is a threshold pumping rate that depends inversely on the decaying lifetime of the atoms and the photons; and (ii) depending on these lifetimes and on the pumping rate, a constant or an oscillatory behavior can be observed. More complex behaviors such as spiking and pattern formation can also be studied with the cellular automaton model

    Computational simulation of laser dynamics as a cooperative phenomenon

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    The different kinds of behavior exhibited by the system in a laser dynamics simulation using a cellular automata model are analyzed. Three distinct types of behavior have been found: laser constant operation, laser spiking and a complex behavior showing irregular oscillations. In the last case, the power spectrum follows a power law of the type 1/f − with exponent close to = 2. In the laser spiking regime, the dependence of the decay rate of the oscillations is found to be in good agreement with the predictions of the theoretical laser rate equations and the experimental phenomenology. In our model the system components evolve under local rules which reproduce the physics of the laser system at the microscopic level, and the laser properties appear as cooperative emergent phenomena associated to these rules

    Evolution of the Correlation between Orthogonal Polarization Patterns in Broad-Area Lasers

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    We measure polarization-resolved instantaneous patterns in a large-aspect ratio quasi-isotropic Nd:YAG laser. High correlation between the instantaneous orthogonal polarization patterns recorded at the earlier stages of the laser pulse has been found due to the strong cross saturation between both polarization modes

    TIC en padres para mejorar el rendimiento académico

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    La investigación tuvo como objetivos, Caracterizar las tecnologías de información y comunicación en padres para en el rendimiento académico de los estudiantes La investigación fue básica de diseño descriptivo con revisión sistemática, las revisiones sistemáticas son investigaciones científicas en las cuales la unidad de análisis son los estudios originales primarios, constituyen una herramienta esencial para sintetizar la información científica disponible. Se encontró que las Tecnologías de Información y Comunicación se encuentran integradas en las familias a nivel internacional, nacional, local urbana y rural, especialmente a través del celular. La actuación de los padres con sus competencias parentales contribuye al desarrollo sostenido de los niños y niñas a su cargo, que se prolonga a través de toda la vida en especial la vida escolar. Integrar las TIC a los padres para ejercer competencia parental en la escuela y ésta evidenciarse en el buen rendimiento académico de los estudiantes es un aspecto necesario. Actualmente se reconoce el papel de las TIC y el apoyo de los padres como elementos fundamentales para llevar adelante la educación remota por tiempos de pandemia; y, aún más convertirse en un aliado para apoyar en la educación de los hijos, evidenciado en el mejor rendimiento académico

    Development and preliminary results of a mobile application to perform pre-inspection of sprayer equipment

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    Por todos es conocido que el presente y futuro de las aplicaciones de productos agroquímicos pasa por una buena regulación, calibración y mantenimiento de los equipos que se utilizan. Tanto Europa como los países miembros y sus comunidades autónomas, en el caso de España, a través de sus instituciones (Universidades, Consejerías, etc.), están trabajando concienzudamente en el protocolo de inspección. Es de prever que en muchos equipos la primera inspección será desfavorable, y además supondrá un coste económico alto para el propietario, independientemente de que el equipo pase la inspección de forma favorable o no. Este hecho hace que el agricultor no conciba este control con la “percepción beneficiosa” que pueda tener la administración. Por todo ello, el Laboratorio de Agricultura de Precisión de la Universidad de Sevilla ha decidido centrarse en el término “pre-inspección” y desarrollar una aplicación gratuita de autocontrol para dispositivos móviles que permita al propietario o su técnico agrícola conocer el estado de su equipo de aplicación antes de acudir a una inspección “oficial” y de esta forma solventar los posibles problemas detectados. En los primeros equipos que han formado parte de este estudio se ha conseguido, por una parte poner en conocimiento y mostrar los elementos y aspectos a controlar y por otra, generar de forma gratuita y fácil un informe donde se indica los elementos y aspectos a solventar antes de ir a una inspección. Esta aplicación de pre-inspección ha sido una herramienta muy valorada por los usuarios como mantenimiento preventivo.It is widely acknowledged that the present and future practice of pesticide applications requires good regulation, calibration and maintenance of the equipment used. European countries and their regional governments, in the case of Spain, through its institutions (Universities, Councils, etc.), are working conscientiously towards inspection protocol. It is expected that many sprayers will not pass the first inspection, and there will be a significant cost to the owner, whether the equipment passes the inspection or not. This fact makes this inspection protocol is not conceived with the “beneficial perception” as the administration may have. Therefore, the Precision Agriculture Laboratory at University of Sevilla has decided to focus on the term “pre-inspection” and develop a free mobile application for self-assessment that allows the owner or agricultural technician check the status of the sprayer before inspection. This would address the possible problem idenfified. For the first spayers considered in this study there have been several achievements: firstly informing about and showing those elements and aspects of the sprayer which need to be controlled and secondly, generating simply and without cost a report describing those elements and aspects which must be resolved before going for an inspection. This approach to pre-inspection has proved to be highly very valued by users as a tool for preventive maintenance

    Búsqueda de nuevas alternativas terapéuticas para el tratamiento de infecciones por adenovirus: cribado de pequeñas moléculas generadas por química combinatoria

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    Motivación: La incidencia de infecciones por adenovirus (HAdV) en pacientes receptores de órgano sólido y especialmente de receptores de progenitores hematopoyéticos, ha aumentado en los últimos años, presentando una elevada morbi- mortalidad (1, 2). Actualmente no existen tratamientos específicos para este tipo de infecciones. Nuestro objetivo fundamental fue identificar moléculas capaces de inhibir la infección por HAdV y determinar su mecanismo de acción como primer paso para el desarrollo de un nuevo antiviral específico frente a HAdV. Métodos: Partimos de una librería de 30 derivados de piperazina. Las moléculas que presentaron actividad inhibitoria > 50% de la infección por HAdV mediante ensayo en placa o mediante "single round infection" se seleccionaron para su caracterización posterior. Su citotoxicidad (CC50) se evaluó mediante cuantificación del XTT metabolizado. Se realizaron así mismo estudios dosis-respuesta de los compuestos activos. También se evaluó la capacidad de las moléculas de inhibir la replicación del virus, para lo cual se llevaron a cabo infecciones de 24h y se cuantificó la producción de "de novo" HAdV ADN mediante PCR cuantitativa a tiempo real (3). La cuantificación de la reducción de la progenie viral por la acción de las moléculas seleccionadas se realizó mediante un ensayo de producción viral y posterior titulación. Resultados: Las moléculas 511, 512 y 513 (50 µM) generaron inhibiciones >50% en el ensayo en placa. Sólo el compuesto 511 generaba una inhibición leve dosis-dependiente. Los valores de CC50 fueron 190, 546 y 85 µM, respectivamente, en base a los cuales el compuesto 513 fue descartado para su posterior caracterización por su elevada toxicidad. Los moléculas 511 y 512 (30 µM) produjeron inhibiciones de la replicación viral del 80% y del 50%, respectivamente. Las moléculas 511 y 512 (30 µM) generaron reducciones en la progenie viral del 44% y del 25%, respectivamente. Conclusiones: Las moléculas 511 y 512 inhiben de manera significativa la infección por HAdV a nivel de la replicación del ADN viral. La optimización de ambos compuestos supone un excelente punto de partida para la obtención de un nuevo agente antiviral específico frente a infecciones por HAdV

    Biorefinery of brewery spent grain by solid-state fermentation and ionic liquids

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    Novel environmentally friendly pretreatments have been developed in recent years to improve biomass fractionation. Solid-state fermentation (SSF) and treatment with ionic liquids show low environmental impact and can be used in biorefinery of biomass. In this work, these processes were assessed with brewery spent grain (BSG). First, BSG was used as a substrate to produce cellulases and xylanases by SSF with the fungi Aspergillus brasiliensis CECT 2700 and Trichoderma reesei CECT 2414. Then, BSG was pretreated with the ionic liquid [N1112OH][Gly] and hydrolyzed with the crude enzymatic extracts. Results showed that SSF of BSG with A. brasiliensis achieved the highest enzyme production; meanwhile, the pretreatment with ionic liquids allowed glucan and xylan fractions to increase and reduce the lignin content. In addition, a mixture of the extracts from both fungi in a ratio of 2.5:0.5 Aspergillus/Trichoderma (v/v) efficiently hydrolyzed the BSG previously treated with the ionic liquid [N1112OH][Gly], reaching saccharification percentages of 80.68%, 54.29%, and 19.58% for glucan, xylan, and arabinan, respectively. In conclusion, the results demonstrated that the BSG biorefinery process developed in this work is an effective way to obtain fermentable sugar-containing solutions, which can be used to produce value-added products.São Paulo Research Foundation | Ref. 2018/25511-1São Paulo Research Foundation | Ref. 2021/15138-4National Council for Scientific and Technological Development | Ref. 408783/2021-4National Council for Scientific and Technological Development | Ref. 312923/2020-1Xunta de Galicia | Ref. GPC-ED431B 2021/23Ministerio de Ciencia e Innovación | Ref. PID2020-115879RB-I0

    Biorefinery of brewery spent grain to obtain bioproducts with high value-added in the market

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    The brewery industry is under economic and environmental pressure to minimize residual management costs, particularly brewery spent grain (BSG), which accounts for 80–85% (w/w) of the total by-products generated. BSG is a lignocellulosic material primarily composed of carbohydrates, proteins and lipids. Developing a biorefinery model for conversion of BSG into value-added products is a plausible idea. Previous work optimized the pretreatment of BSG with the ionic liquid [N1112OH][Gly] and further release of fermentable sugar-containing solutions by enzymatic hydrolysis, using an enzymatic cocktail obtained by solid-state fermentation of BSG with Aspergillus brasiliensis CECT 2700 and Trichoderma reesei CECT 2414. The current work ends the biorefinery process, studying the fermentation of these culture media with two LAB strains, Lactobacillus pentosus CECT 4023 and Lactobacillus plantarum CECT 221, from which the production of organic acids, bacteriocins, and microbial biosurfactants (mBS) was obtained. In addition to the bacteriocin activity observed, a mass balance of the whole biorefinery process quantified the production of 106.4 g lactic acid and 6.76 g mBS with L. plantarum and 116.1 g lactic acid and 4.65 g mBS with L. pentosus from 1 kg of dry BSG. Thus, BSG shows a great potential for waste valorization, playing a major role in the implementation of biomass biorefineries in circular bioeconomy.Agencia Estatal de Investigación | Ref. PID2020–115879RB-I00São Paulo Research Foundation | Ref. 2018/25511–1São Paulo Research Foundation | Ref. 2023/09256–0Conselho Nacional de Desenvolvimento Científico e Tecnológico (Brasil) | Ref. 408783/2021–4Conselho Nacional de Desenvolvimento Científico e Tecnológico (Brasil) | Ref. 312923/2020–1Xunta de Galicia | Ref. GPC-ED431B 2021/23Universidade de Vigo/CISU

    Recovery and reuse of ionic liquid cholinium glycinate in the treatment of brewery spent grain

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    Recently, the ability of the biocompatible ionic liquid cholinium glycinate (N1112OHGly) for waste vegetable delignification like brewery spent grain (BSG) has been proved. However, the technical viability should march hand in hand with economic competitiveness. Therefore, the first step must address the reuse of the ionic liquid to mitigate the high cost associated with the synthesis of this kind of neoteric solvents. Different antisolvent-based strategies have been considered, in the present research work, to produce a delignified carbohydrate rich material (CRM) and reuse the ionic liquid. It was checked that the addition of a mixture of water: acetone (1:1 v/v) was able to efficiently precipitate carbohydrates with high levels of delignification, while about 97% of the ionic liquid is recovered at a purity near 72%. The use of this strategy allowed reusing N1112OHGly for 5 cycles and FTIR and XRD spectroscopy, scan electron microscopy (SEM) and, quantitative acid hydrolysis evidenced the suitability of the proposed process for the competitive sequential BSG delignification. Liquid chromatography sheds light on the recovery percentages and purity of the ionic liquid after each use.Xunta de Galicia | Ref. ED481A-2017/320Xunta de Galicia | Ref. ED431B 2018/5
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