Catálogo de los manuscritos de la colección Rubén Vargas Ugarte

La colección Vargas Ugarte está constituida por manuscritos, impresos coloniales e impresos modernos (americanos y europeos), que datan del Siglo XVI hasta el XX inclusive. El presente catálogo se encuentra enfocado en la colección de documentos manuscritos

Buenas prácticas docentes universitarias UARM

El año 2020 ingresamos a una pandemia mundial que nos ha transformado. Ha cambiado muchos aspectos de nuestra vida, entre ellas las formas y herramientas para la enseñanza. Durante 2 años la universidad mantuvo todos sus servicios, todas sus clases virtuales. Este año, el 2022 ha sido el año del retorno a la presencialidad, de podernos volver a encontrar en el campus. Sin embargo, ya la realidad no es la misma. Estudiantes, docentes y personal administrativo tuvimos que reinventarnos para adaptarnos, tuvimos que buscar caminos diferentes para aprender, para enseñar, para comunicarnos y para acompañarnos. Por ello, ahora, en el retorno, no podemos volver a la misma realidad que en el año 2020, como si nada hubiese pasado, como si no hubiésemos tenido este importante proceso de cambio. Este nuevo contexto, nos ha resaltado lo importante de la innovación pedagógica dentro del aula, que los docentes debemos experimentar, aplicar y promover nuevas prácticas docentes. A partir de dichas experiencias, debemos poder compartirlas, debatirlas, reflexionar para aprender aquello que potencia los procesos de aprendizaje de nuestros y nuestras estudiantes. Solo así, podremos adaptarnos a este mundo cambiante y podremos, a su vez, formar al alumnado en competencias necesarias para los profesionales que necesita nuestro país hoy día. Por ello, este libro, que recopila buenas prácticas docentes es tan importante. Felicitaciones a todos y todas las docentes que se suman a esta experiencia. Animo a más docentes a sumarse a las diversas experiencias de innovación docente que promueve la UARM que nos permiten promover nuestro modelo educativo humanista

Kinetic synergistic effect in co-pyrolysis of Eucalyptus globulus with high and low density polyethylene

The pyrolysis of Eucalyptus globulus (EG) with different blends of high density polyethylene (HDPE) and low density polyethylene (LDPE) by thermogravimetry has been studied. ASTM-E1641-16 standard method has been used to evaluate the kinetics during the pyrolysis of the studied blends. For all feedstocks (EG, HDPE and LDPE) and blends studied, the relative content (%) of the volatile organic compound has been determined by GC–MS analysis. Different synergistic effects on the activation energy of EG blends with HDPE and LDPE have been found. EG-HDPE blends showed a minimum activation energy (Ea) (125 kJ mol−1) at the 80% EG–20% HDPE ratio, while the minimum Ea value for EG-LDPE blends was found at the 60% EG–40% LDPE ratio (135 kJ mol−1) has been identified. To test which components exert a greater synergistic effect, mixtures of HDPE and LDPE with the main components of eucalyptus (cellulose, hemicellulose and lignin) have also been studied. However, no synergistic effects on the pyrolysis of cellulose have been detected. Moreover, in hemicellulose and lignin with both types of polyethylene mixtures, a significant decrease in Ea has been appreciated. The lowest Ea values for 60% cellulose–40% HDPE (167 kJ mol−1) and 60% lignin–40% HDPE (140 kJ mol−1) has been calculated. On the other hand, minimum values for 40% cellulose–60% LDPE (166 kJ mol−1) mixture and for 40% lignin–60% LDPE (168 kJ mol−1) mixture have been detected. Thus, the decrease in both Ea and the Arrhenius pre-exponential factor on the eucalyptus-polyethylene blends to the presence of hemicellulose and lignin can be attributed. Moreover, during the co-pyrolysis of HDPE-EG mixtures, n-paraffins, ketones, phenols and sugars are the main VOCs identified. In contrast, in LDPE-EG mixtures, only n-paraffins (55%) and olefins (44%) have been identified.This study received financial support from Green Asphalt project (ref. 802C1800001) co-funded 80% by FEDER European Programme and 20% by the Regional Government of Andalusia (Agency for Innovation and Development of Andalusia (IDEA) and (Operational Programme FEDER Andalusia 2014–2020, Project UHU–1255540), Spain. Funding for open access charge: Universidad de Huelva / CBU

Ultrasound extraction optimization for bioactive molecules from Eucalyptus globulus leaves through antioxidant activity

Antioxidant products present a very high added value and are demanded in the market. The optimization of their extraction is a high-stakes matter for both economic and environmental points of view. Ultrasound extraction has been considered one of the most promising methods, so the relative importance of key parameters may have decisive economic significance. For this reason, different parameters that have influence on the extraction capacity such as ultrasound power, time, temperature, pH and % ethanol in water have been studied to know the relationships between the independent parameters and their influence on the extraction from Eucalyptus globulus leaves. An experimental Box-Behnken factorial design and subsequent analysis by neural networks have been used. The relative influence of each parameter varies according to the nature of the extracted compound. In this regard, the higher capacity of extraction of the selected antioxidant compounds by means of the variation of the operation conditions can be facilitated. For all the studied compounds, temperature has been the most important parameter for their extraction. The relative content (%) of bioactive compounds (terpenes) in the optimized Eucalyptus globulus extract has been performed by GC–MS analysis

Optimization of bioactive compounds by ultrasound extraction and gas chromatography - mass spectrometry in fast-growing leaves

Fast-growing crops are of great economic importance in the production of paper pulp and energy. The commercialization of the bioactive components from underutilized parts could provide additional value to these crops. In the present study, chromatography gas coupled to mass spectrometry triple quadrupole (GC–MS/MS) and ultrasound extraction technique was used in the bioactive compounds determination in fast-growing crops leaves. Twenty-one terpenes and eight polyphenolic bioactive compounds were studied. Prior to GC–MS/MS, polydimethylsiloxane (PDMS) - stir bars preconcentration and trimethylsilane (TMS) derivatization steps were used for terpenes and polyphenolic compounds, respectively. Several parameters (pH, temperature, ethanol–water mixtures, ultrasound power, and ultrasound time) of the extraction step were optimized by central composite experimental design. Ethanol content, ultrasound power, and ultrasound time were the parameters that most influence the extraction efficiency of terpenes in biomass residues, while for polyphenolic compounds it was temperature and ultrasound time. The optimal ultrasound extraction conditions for terpenes were 60% ethanol, pH 4, 80 W, 40 ºC, and 15 min, whereas for polyphenolic compounds they were 60% ethanol, pH 4, 120 W, 50 ºC, and 15 min. The detection limits (LOD) were in the range of 0.200–3.02 µg kg−1 and 7.9–540 µg kg−1 for terpenes and polyphenolic compounds, respectively. The developed analytical method was applied to twelve fast-growing leaves (Leucaene (diversifolia and leucocephala), Eucalyptus (globulus and urograndis), Populus (I214 and AF2), Prosopis (alba and juliflora), Robinia, Tagasaste, Ulmus pumila, and Paulownia). Eucalyptol was the mayor terpene present in all the plants studied, while chlorogenic and quinic acid were the mayor phenolic compounds.This study was supported by the Ministry of Economy and Competitiveness (Spain), as well as by the National Research Program Oriented to the Challenges of Society (Project PID2020-112875RB-C21 funded by MCIN/AEI /10.13039/501100011033), and the Ministry of Innovation, Science and Business of the Government of the Junta of Andalusia (Spain), the Operative Program is framed within FEDER Andalusia 2014–2020 (Project UHU-125540). Funding for open access charge: Universidad de Huelva / CBUA

Bioorthogonal uncaging of cytotoxic paclitaxel through Pd nanosheet-hydrogel frameworks

The promising potential of bioorthogonal catalysis in biomedicine is inspiring incremental efforts to design strategies that regulate drug activity in living systems. To achieve this, it is not only essential to develop customized inactive prodrugs and biocompatible metal catalysts but also the right physical environment for them to interact and enable drug production under spatial and/or temporal control. Toward this goal, here, we report the first inactive precursor of the potent broad-spectrum anticancer drug paclitaxel (a.k.a. Taxol) that is stable in cell culture and labile to Pd catalysts. This new prodrug is effectively uncaged in cancer cell culture by Pd nanosheets captured within agarose and alginate hydrogels, providing a biodegradable catalytic framework to achieve controlled release of one of the most important chemotherapy drugs in medical practice. The compatibility of bioorthogonal catalysis and physical hydrogels opens up new opportunities to administer and modulate the mobility of transition metal catalysts in living environs

Análisis de los factores que inciden en la exportación de las mypes del sector textil-confecciones. Casos de estudio: Corporación Stealth, Nevih Plus Size y Pijamas Rozzé Latina del emporio comercial de Gamarra

El presente estudio plantea la necesidad de conocer cuáles son los factores externos, las características del fundador y los factores internos que inciden en la exportación de las MYPES textiles de Gamarra a partir de la construcción de un modelo referencial adaptado al contexto de los casos de estudio. Este modelo se obtuvo tomando como referencia los modelos mencionados en la literatura. Cabe precisar que para esta investigación el concepto de exportación es entendido como el primer paso de la estrategia de internacionalización. La aproximación a la investigación se realiza a través de un estudio de caso múltiple de tres MYPES pertenecientes al sector textil-confecciones que orienta sus ventas a niveles nacional e internacional. En consecuencia, se analiza la situación actual de los casos de estudio con entrevistas semi-estructuradas a los actores relevantes en cada empresa: el fundador, el administrador y el jefe de operaciones. Finalmente, como resultado de la investigación se presentan los hallazgos fundamentales, así como las conclusiones y recomendaciones sobre mejoras en la gestión de exportación aplicables a los casos de estudio. Además, se comparten los aprendizajes y líneas futuras de investigación que se obtuvieron del presente trabajo.Tesi

PLANEACIÓN DIDÁCTICA GENERAL DE LA ASIGNATURA: METODOLOGÍA DE LA INVESTIGACIÓN II

GUÍA DIDÁCTICA / PLANEACIÓN DIDÁCTICA (NMS

Viability of probiotic bacteria Bacillus Polymyxa, Bacillus Megaterium and Lactobacillus Delbruekii subsp. bulgaricus microencapsulated under the spray-drying technique

Most microorganisms that are considered as probiotics have received much attention in recent scientific research, supporting their important role in improving bowel function in both human and animal health. Probiotics have the ability to modulate the immune system of the host, compete for colonization with pathogenic microorganisms and improve digestion of food among many other benefits. One disadvantage in the use of probiotics in food processing is the low viability of probiotics that may be affected by environmental conditions including air, humidity and temperature. An alternative to avoid these effects is by developing protective conditions that ensure the viability and activity of these microorganisms during use and food application, ensuring they are released into the intestine where their action is required. Accordingly, this study aims to assess the influence of spray drying technique with maltodextrin and inulin on viability of a consortium of three types of probiotic bacteria widely used in the food industry.La mayoría de microorganismos considerados como probióticos, tienen un papel importante en el mejoramiento de la función intestinal, tanto para la salud humana como animal. Gran parte de estos microorganismos probióticos, son muy sensibles a condiciones ambientales como la humedad, la temperatura, la concentración de oxígeno, las sales biliares, y el pH estomacal y, al ser procesados o almacenados como alimentos funcionales se puede ver afectada su viabilidad. Debido a esto, es necesario desarrollar condiciones protectoras que garanticen la viabilidad y actividad de estos microorganismos cuando son adicionados y procesados en matrices alimentarias, y asegurar que sean liberados en el intestino donde se precisa su acción. De acuerdo a lo anterior, el presente proyecto propone evaluar la influencia de la técnica de secado por aspersión con maltodextrina más inulina sobre la viabilidad de un consorcio de tres tipos de bacterias probióticas ampliamente utilizadas en la industria alimentaria