56 research outputs found

    Acerca de la evaluación del desempeño profesoral en la Universidad de Antioquia

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    RESUMEN: Es necesario afinar los instrumentos de evaluación con indicadores de calidad y pertinencia en el marco del plan de desarrollo de la universidad, articulado al plan de desarrollo de la unidad académica; pues es claro que el plan de trabajo del profesor es el resultado de una concertación entre él y su jefe inmediato, coherente con dichos planes de desarrollo. Además, debe indagarse acerca de las habilidades y competencias de quien evalúa para determinar la calidad y pertinencia de los criterios de evaluación utilizados en tan complejo proceso, el cual debe ser realizado haciendo seguimiento de la calidad y el cumplimiento del mismo

    By-product recovery of Opuntia spp. peels: Betalainic and phenolic profiles and bioactive properties

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    [EN] Opuntia spp. are a tropical and subtropical plant that provides both edible green steams and fruits; however, the processing of this fruits results in the accumulation of enormous amount of by-products that can be a source of bioactive and pigmented compounds. Herein, three cactus pear from the species Opuntia focus-indica var. sanguigna (OS) and gialla (OG) and Opuntia engelmannii (OE) were fully characterized regarding their phenolic and betalain composition and correlated with their antioxidant and antimicrobial activities. The hydroethanolic extracts of OE gave the highest amount of phenolic compounds isorhamentin-O-(deoxyhexosyl-hexoside) and betacianins (betanin); however, no betaxanthins were identified in this sample. This sample also revealed the lowest EC50 values in all the antioxidant activity assays. Regarding antimicrobial activity, the hydroethanolic extracts of all species revealed to be more active than ampicillin. The pivotal objective of this work was to focus on exploring by-product biocompounds and possible outputs, thus, we could suggest the use of these natural colorants with intrinsic antioxidant and antimicrobial activity, which would grant industries to produce cleaner label products with functional benefits.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2013) and L. Barros contract. This work is funded by the European Structural and Investment Funds (FEEI) through the Regional Operational Program North 2020, within the scope of Project NORTE-01-0145-FEDER-023289 (DeCodE) and ValorNatural (R). B. Melgar (No. 329930) also thanks CONACyT for his grant. The authors are grateful for a grant from the Serbian Ministry of Education, Sciences and Technological Development (no. 173032). The authors would also like to thank Dr. Carlos Aguiar for the botanical identification of these species.Melgar-Castañeda, B.; Dias, MI.; Ciric, A.; Sokovic, M.; Garcia-Castello, EM.; Rodríguez López, AD.; Barros, L.... (2017). By-product recovery of Opuntia spp. peels: Betalainic and phenolic profiles and bioactive properties. Industrial Crops and Products. 107:353-359. https://doi.org/10.1016/j.indcrop.2017.06.011S35335910

    Ordenha mecânica nas explorações de caprinos de Trás-os-Montes (Portugal): problemas e dificuldades para a sua divulgação

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    Na região de Trás-os-Montes (nordeste de Portugal) a exploração de cabras de leite, principalmente da raça Serrana, autóctone, é uma actividade relativamente importante do ponto de vista socioeconómico, porque se trata de uma região pobre e onde são raras as actividades económicas alternativas para a população rural. Para o desenvolvimento da actividade e para a melhoria da qualidade e quantidade de leite produzido, é importante melhorar as condições de ordenha, especialmente quanto às instalações e equipamentos; e às condições de trabalho do ordenhador. A maioria das explorações de caprinos da região pratica a ordenha manual. Este tipo de ordenha tem vários problemas quanto às condições de trabalho e à qualidade do leite recolhido. Nos últimos anos desenvolveram-se várias acções no sentido de melhorar as condições de ordenha e de incentivar os criadores para a adopção de ordenha mecânica. No entanto, verificam-se alguns problemas e dificuldades dos criadores na adopção e utilização destes equipamentos. Com este trabalho, pretende-se identificar os problemas e dificuldades que resultaram da adopção/utilização de equipamentos de ordenha mecânica em explorações de cabras de leite da região de Trás-os-Montes. O estudo da ordenha mecânica abrangeu vários aspectos: os equipamentos utilizados; a organização do trabalho e das instalações; e os procedimentos do ordenhador no trabalho de ordenha. Foram estudadas as explorações de caprinos de raça Serrana da região de Trás-os-Montes que utilizam qualquer tipo de ordenha mecânica. A informação recolhida permite concluir que há dificuldades na adaptação ao uso de novas técnicas de ordenha e equipamentos. Os problemas estão, principalmente, relacionados com a organização do trabalho e do local da ordenha, e com a aprendizagem da correcta utilização dos equipamentos. De futuro, será importante considerar o desenvolvimento de acções de apoio técnico aos criadores, no sentido de melhorar as instalações/local de ordenha e a utilização dos equipamentosIn the national context, the region of Trás-os-Montes, in Northeastern Portugal, is one of the most depopulated and least favoured areas. In this region, goat breeding has great socioeconomic importance due to the number of families that are economically dependent on these activities. This importance is particularly due to the scarcity of alternative economic activities. To improve goat breeding, milk production and milk quality, it is important to enhance milking conditions, mainly in facilities, equipment and working conditions. Presently, there are very few farms with milking machines. Mostly, goats are hand-milked inside the shelters. As a result of actions carried out over the recent years involving strategies to improve milking conditions on goat farms in the region, some breeders adopted mechanical milking. For these breeders, mechanical milking is a new technology, they are inexperienced and they lack knowledge about the correct use of these machines and best milking practices. To study mechanical milking we established the following aspects to consider: working organization and facilities, milking operations, and procedures performed by milkers. Goat farms that used mechanical milking in the region of Trás-os-Montes were studied. From the information collected, it was found some difficulties in the adaptation to the use of new milking techniques. Main problems are related to working organization, facilities and equipment utilization

    Uso de las tecnologías de la información y la comunicación en las empresas: Uso de tecnologias de informação e comunicação nas empresas

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    Este artículo pretende analizar el uso de las TIC en la gestión empresarial, principalmente  en las pequeñas y medianas empresas (PyMEs). Las TIC cuentan con más de tres décadas de existencia y la adopción de estas herramientas en las empresas fue progresiva. Al inicio de años 90 las empresas grandes hicieron las inversiones en el área de nuevas tecnologías, principalmente como herramienta de soporte  a sus funciones administrativas. Con la reducción de los costes y con la simplificación de estas tecnologías, los servicios paulatinamente se extendieron también a las pequeñas y medianas empresas y el impacto de estas tecnologías es visible en todas las áreas de la actividad de las empresas. El trabajo analiza también el nivel de aplicación de las TIC en las PyMEs en la ciudad de Riobamba – Ecuador.  A 354 empresas en Riobamba se definió como PyMEs y se ha desarrollado un estudio empírico a través de 172 encuestas realizadas a gerentes y/o propietarios de las empresas.  Finalmente, se comenta los descubrimientos más destacados de este trabajo de investigación señalando que a pesar de que las TIC ya forman parte de la mayoría de las empresas, sin embargo, no existe el uso más complejo de estas herramientas tecnológicas

    Red seaweeds as a source of nutrients and bioactive compounds: Optimization of the extraction

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    The present work aimed to determine the nutritional composition (ash, protein, fat, carbohydrate content and energy value), phenolic compounds, pigments and organic acids content of three typical red algae from the Northwest of Spain: Chondrus crispus, Mastocarpus stellatus, and Gigartina pistillata; as well as their antioxidant and antimicrobial activities. Furthermore, the present work compared two extraction techniques: conventional heat assisted extraction (HAE) and high pressure assisted extraction (HPAE) to maximize the yield and the concentration of target compounds. Different independent variables were considered for the response study. Time (t) and percentage of ethanol of the solvent (S) were chosen for both techniques and temperature (T) and pressure (P) were used for HAE and HPAE, respectively. The experiments were designed following a response surface methodology (RSM) approach. The obtained results showed a similar nutritional composition between algae samples: low-fat content and high content of proteins, carbohydrates and energy. All tested algae showed good antioxidant and antimicrobial properties. Finally, HEA demonstrated to be the most efficient extraction technique. This study confirms the potential of red algae to be part of the human diet as a source of non-animal protein, due to its nutritional content, phenolic profile, pigments concentration and bioactive properties, which proves that HAE is the optimum technique for the extraction maximization.The research leading to these results was supported by MICINN supporting the Ramón y Cajal grant for M.A. Prieto (RYC-2017-22891); by Xunta de Galicia supporting the program EXCELENCIA-ED431F 2020/12 and the post-doctoral grant of M. Fraga-Corral (ED481B-2019/096); by University of Vigo for the predoctoral grant of M. Carpena (Uvigo-00VI 131H 6410211); by Becas de Fundación ONCE Program “Oportunidad al Talento” that supports the work of A. Soria-Lopez; by Ibero-American Program on Science and Technology (CYTED—AQUA-CIBUS, P317RT0003) and by the Bio Based Industries Joint Undertaking (JU) under grant agreement No 888003 UP4HEALTH Project (H2020-BBI-JTI-2019). The JU receives support from the European Union’s Horizon 2020 research and innovation program and the Bio Based Industries Consortium. The project SYSTEMIC Knowledge hub on Nutrition and Food Security, has received funding from national research funding parties in Belgium (FWO), France (INRA), Germany (BLE), Italy (MIPAAF), Latvia (IZM), Norway (RCN), Portugal (FCT), and Spain (AEI) in a joint action of JPI HDHL, JPI-OCEANS and FACCE-JPI launched in 2019 under the ERA-NET ERA-HDHL (no. 696295). This work has also been supported by the Ministry of Education, Science and Technological Development of Republic of Serbia (451-03-68/2020-14/200007). The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES to CIMO (UIDB/00690/2020); national funding by FCT, P.I., through the institutional scientific employment program-contract for L. Barros and C. Pereira contracts; to the project AllNat for the contract of C. Caleja (Project AllNat POCI-01-0145-FEDER-030463) and to the Valor Natural project for the contract of E. Pereira (Mobilized Project Norte-01-0247-FEDER-024479).info:eu-repo/semantics/publishedVersio

    Nueva información del perfil de compuestos bioactivos, potencial antioxidante y antiproliferativo de Parkinsonia praecox (Fabaceae)

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    Background and Aims: Parkinsonia praecox,“palo brea”, is a medicinal plant distributed in the Mexican Sonoran Desert. However, there is little information about the chemical composition and biological potential of this plant. As a consequence, the objective of the present study was to determine the chemical composition, as well as the antioxidant and antiproliferative activity, of P. praecox. Methods: Methanolic extracts of stems (PPS), berries (PPB) and flowers (PPF) were performed. Chemical composition was determined by phytochemical screening, Folin Ciocalteu and UPLC-DAD methods. Antioxidant activity was determined by DPPH, ABTS, ORAC and FRAP methods. Antiproliferative activity was evaluated by MTT against A549 (non-small-cell lung cancer cells), MDA-MB-231 (triple negative breast cancer), PC-3 (adenocarcinoma prostate cancer grade IV), HeLa (human cervical cancer) and L929 (non-cancerous subcutaneous connective tissue) cell lines. Results: Phytochemical screening showed the presence of terpenes, phenolic compounds, flavonoids, tannins and sugars in the extracts. PPS showed the highest (p<0.05) concentration of phenolic compounds (65.5 mg GAE/g), identifying and quantifying quercetin (218.86 µg/g). Additionally, PPS exhibited the highest capacity (p<0.05) to stabilize the DPPH (IC50: 137 µg/ml), ABTS (39.56 µM TE/g), hydroxyl radicals (ORAC: 1777.78 µM TE/g), and to reduce metals (FRAP: 935.6 µM Fe(II)/g). Similar behavior was observed in antiproliferative activity, since PPS presented the highest cytotoxicity (p<0.05): A549 (IC50: 341.3 µg/ml), MDA-MB-231 (IC50: 147.3 µg/ml), PC-3 (IC50: 78.8 µg/ml), HeLa (IC50: 121.6 µg/ml) and L929 (IC50: 93.29 µg/ml). Conclusion: This is the first research where the bioactive compound profile and the biological potential of P. praecox are reported. The results show the strong association between the antioxidant and the antiproliferative activities with the presence of phenolic compounds. This represents a potential support for the development of pharmacological therapies.Antecedentes y Objetivos: Parkinsonia praecox,“palo brea”, es una planta medicinal distribuida en el Desierto de Sonora en México. Sin embargo, existe poca información acerca de la composición química y del potencial biológico de esta planta. Basado en lo anterior, el objetivo del presente estudio fue determinar la composición química y el potencial antioxidante y antiproliferativo de P. praecox. Métodos: Se prepararon extractos metanólicos de tallos (PPS), frutos (PPB) y flores (PPF). La composición química se determinó a través de los métodos de perfil fitoquímico, Folin-Ciocalteu y UPLC-DAD. La actividad antioxidante se evaluó por los métodos DPPH, ABTS, ORAC y FRAP. La actividad antiproliferativa se determinó por el ensayo MTT contra las líneas celulares A549 (cáncer de pulmón de células no pequeñas), MDA-MB-231 (cáncer de mama triple negativo), PC-3 (cáncer de próstata grado IV), HeLa (cáncer de cervix) y L929 (tejido conectivo subcutáneo no canceroso). Resultados: El perfil fitoquímico mostró la presencia de terpenos, compuestos fenólicos, flavonoides, taninos y azúcares en los extractos. PPS presentó la concentración más elevada (p<0.05) de compuestos fenólicos (65.5 mg GAE/g), identificando y cuantificando quercetina (218.86 µg/g). Además, PPS mostró la capacidad más elevada (p<0.05) para estabilizar a los radicales DPPH (IC50: 137 µg/ml), ABTS (39.56 µM TE/g), hidroxilo (ORAC: 1777.78 µM TE/g), y reducir metales (FRAP: 935.6 µM Fe(II)/g). Un comportamiento similar se observó en la actividad antiproliferativa, ya que PPS mostró la citotoxicidad más elevada (p<0.05): A549 (IC50: 341.3 µg/ml), MDA-MB-231 (IC50: 147.3 µg/ml), PC-3 (IC50: 78.8 µg/ml), HeLa (IC50: 121.6 µg/ml) y L929 (IC50: 93.29 µg/ml).Conclusión: Este es el primer estudio donde se reporta el perfil de compuestos bioactivos y el potencial biológico de P. praecox. Los resultados muestran una fuerte asociación entre la actividad antioxidante y antiproliferativa con la presencia de compuestos fenólicos. Esto representa un potencial soporte para el desarrollo de terapias farmacológicas

    Potential use of elderberry (Sambucus nigra l.) as natural colorant and antioxidant in the food industry: a review

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    The food industry, in response to current consumer demand for natural and functional foods, is constantly evolving and reformulating traditional products formulations. Thus, during the last decades, multiple natural sources have been investigated to replace the need to add synthetic additives. In addition, the use of natural sources can also increase the nutritional quality of the food. With this in mind, elderberry is used in the food industry for certain purposes. However, its potential is much higher than the number of applications it currently has. Its high content of anthocyanins, as well as other polyphenols and vitamins, means that it can be used by the food industry both as a colorant and as an antioxidant. In addition, the incorporation of these bioactive compounds results in functional foods, with a high antioxidant capacity. Moreover, the inclusion of elderberry products in foods formulation increases their shelf-life, but the correct amount and strategy for adding elderberry to food should be studied to ensure a positive effect on nutritional and technological properties without affecting (or improving) the sensory quality of foods. Therefore, this manuscript aims to review the main bioactive compounds present in elderberries, as well as their potential uses in the food industry.The authors thank GAIN (Axencia Galega de Innovación) for supporting this review (grant number IN607A2019/01). Authors (R.D., M.P., P.E.S.M., E.M.S.L., and J.M.L.) are members of the HealthyMeat network, funded by CYTED (ref. 119RT0568). Authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES to the CIMO (UIDB/00690/2020). L. Barros thanks the national funding by FCT, P.I., through the institutional scientific employment program for her contract.info:eu-repo/semantics/publishedVersio
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