186 research outputs found
Two Frequenins in Drosophila: unveiling the evolutionary history of an unusual Neuronal Calcium Sensor (NCS) duplication
13 pages, 4 figures, 1 table, 5 additional files.[Background] Drosophila Frequenin (Frq), the homolog of the mammalian Neuronal Calcium Sensor-1 (NCS-1), is a high affinity calcium-binding protein with ubiquitous expression in the nervous system. This protein has an important role in the regulation of neurotransmitter release per synapse, axonal growth and bouton formation. In D. melanogaster, Frequenin is encoded by two genes (frq1 and frq2), a very unexpected feature in the Frq/NCS-1 subfamily. These genes are located in tandem in the same genomic region, and their products are 95% identical in their amino acid sequence, clearly indicating their recent origin by gene duplication. Here, we have investigated the factors involved in this unusual feature by examining the molecular evolution of the two frq genes in Drosophila and the evolutionary dynamics of NCS family in a large set of bilaterian species.[Results] Surprisingly, we have found no amino acid replacements fixed across the twelve Drosophila species surveyed. In contrast, synonymous substitutions have been prevalent in the evolution of the coding region of frq1 and frq2, indicating the presence of strong functional constraints following gene duplication. Despite that, we have detected that significant evolutionary rate acceleration had occurred in Frq1 in early times from the duplication, in which positive selection (likely promoting functional diversification) had probably an important role. The analysis of sequence conservation and DNA topology at the non-coding regions of both genes has allowed the identification of DNA regions candidates to be cis-regulatory elements. The results reveal a possible mechanism of regulatory diversification between frq1 and frq2.[Conclusions] The presence of two Frequenins in Drosophila and the rapid accumulation of amino acid substitutions after gene duplication are very unusual features in the evolution of the Frq/NCS-1 subfamily. Here we show that the action of positive selection in concordance with some extent of regulatory diversification might explain these findings. Selected amino acid substitutions in Frq1 likely contributed to the functional divergence between the two duplicates, which, in turn, should have diverged in their regulation by Ecdysone-induced early genes.Research
was funded by grants BFU 2006-10180 and the European Research Network
of Excellence MYORES ref.: CE-511978.Peer reviewe
Thermal and Dielectric Characterization of Multi-Walled Carbon NanotubesThermoplastic Polyurethanes Composites
[EN] Multi-walled carbon nanotubes-thermoplastic polyurethanes composites were characterized by means of differential scanning calorimetry and dielectric relaxation spectroscopy. The composite is characterized by two glass transition temperatures T (g) . The T (g) associated with the soft segment decreases by increasing of carbon nanotubes content, while carbon nanotubes content has practically no effect on the value of the T-g associated with the hard segments. It was observed that rising the temperature and carbon nanotubes content resulted in the increased of both the dielectric permittivity and the loss factor. The presence of carbon nanotubes produces an enhancement of charge carriers trapping, increasing the electrical conductivity. The electrical conductivity of the composite was found to exhibit an insulator to conductor transition at a carbon nanotubes critical content, i.e., the percolation threshold, near 6 wt %.MJS and MC acknowledge the financial support of the DGCYT through Grant MAT2015-63955-R.Sanchis Sánchez, MJ.; Carsí Rosique, M.; Gracia-Fernandez, C. (2017). Thermal and Dielectric Characterization of Multi-Walled Carbon NanotubesThermoplastic Polyurethanes Composites. Polymer Science Series A. 59(4):543-553. https://doi.org/10.1134/S0965545X17040083S543553594D. W. Schaefer and R. S. Justice, Macromolecules 40 (24), 8501 (2007).D. R. Raul and L. M. Robeson, Polymer 49 (15), 3187 (2008).P. J. Brigandi, J. M. Cogen, and R. A. Pearson, Polym. Eng. Sci. 54 (1), 1 (2014).H. Deng, L. Lin, M. Ji, S. Zhang, M. Yang, and Q. Fu, Prog. Polym. Sci. 39 (4), 627 (2014).Polymer-Matrix Composites. Types, Applications and Performance, Ed. by R. Kumar (Nova Sci. Publ., New York, 2014).Z. Wenying and Y. Demei, J. Appl. Polym. Sci. 118 (6), 3156 (2010).Y. P. Mamunya, V. V. Davydenko, P. Pissis, and E. V. Lebedev, Eur. Polym. J. 38 (9), 1887 (2002)B. Redondo-Foj, P. Ortiz-Serna, M. Carsí, M. J. Sanchis, M. Culebras, C. M. Gomez, and A. Cantarero, Polym. Int. 64, 284 (2015).S. Deng, Y. Zhu, X. Qi, W. Yu, F. Chen, and Q. Fu, RSC Adv. 6 (51), 45578 (2016).M. Khissi, M. El Hasnaoui, J. Belattar, M. P. F. Graca, M. E. Achour, and L. C. Costa, J. Mater. Environ. Sci. 2 (3), 281 (2011).M. Hindermann-Bischoff and F. Ehrburger-Dolle, Carbon 39 (3), 375 (2001).I. Balberg, Carbon 40 (2), 139 (2002).M. Moniruzzaman and K. I. Winey, Macromolecules 39, 5194 (2006).A. Bharati, R. Cardinaels, J. W. Seo, M. Wubbenhorst, and P. Moldenaers, Polymer 79 (19), 271 (2015)Szycher's Handbook of Polyurethanes, Ed. by M. Szycher (CRC Press, Washington, DC, 1999).C. Prisacariu, Polyurethane Elastomers. From Morphology to Mechanical Aspects (Springer, New York, 2011).P. Król, Prog. Mater. Sci. 52 (6), 915 (2007).P. R. de C. Coelho Filho, M. S. Marchesin, A. R. Morales, and J. R. Bartoli, Mater. Res. 17 (1), 127 (2014).R. H. Baughman, A. A. Zakhidov, and W. A. de Heer, Science 297 (5582), 787 (2002).J. Kim and Y. Son, Polymer 88, 29 (2016)M. A. Nikje Mir and A. Yaghoubi, Polimery 59(11–12), 776 (2014).C. Kingston, R. Zepp, A. Andrady, D. Boverho, R. Fehir, D. Hawkins, J. Roberts, P. Sayre, B. Shelton, Y. Sultan, V. Vejins, and W. Wohlleben, Carbon 68, 33 (2014).Anelastic and Dielectric Effects in Polymeric Solids, Ed. by N. G. McCrum, B. E. Read, and G. Williams (Wiley, London, 1967).In Broadband Dielectric Spectroscopy, Ed. by F. Kremer, and A. Schonhals (Springer, Berlin, 2003).E. Riande and R. Diaz-Calleja, Electrical Properties of Polymers (Marcel Dekker, New York, 2004).I. M. Hodge, K. L. Ngai, and C. T. Moynihan, J. Non-Cryst. Solids 351 (2), 104 (2005).A. Eceiza, M.D. Martin, K. de la Caba, G. Kortaberria, N. Gabilondo, M. A. Corcuera, and I. Mondragon, Polym. Eng. Sci. 48 (2), 297 (2008)A. K. Jonscher, Universal Relaxation Law: A Sequel to Dielectric Relaxation in Solids (Chelsea Dielectrics Press, London, 1996), Chap. 5.A. K. Jonscher, Nature 267, 673 (1977).G. Li, L. Feng, P. Tong, and Z. Zhai, Prog. Org. Coat. 90, 284 (2016)K. Petrie, M. Kontopoulou, and A. Docoslis, Polym. Compos. 37 (9), 2794 (2016)N. Aranburu and J. I. Eguiazabal, Polym. Compos. 35 (3), 587 (2014)Impedance Spectroscopy. Theory, Experiment, and Applications, Ed. by E. Barsoukov and J. R. Macdonals (Wiley Intersci., New York, 2005).S. Havriliak and S. J. Havriliak, Dielectric and Mechanical Relaxation in Materials (Hanser, Munich, 1997), p. 57.S. Havriliak and S. Negami, Polymer 8 (4), 161 (1967)
Calibración de parámetros de infiltración y rugosidad con un modelo numérico para riego con surcos cerrados
[ES] Se presenta la calibración de los parámetros que intervienen en las ecuaciones de infiltración de Green y Ampty de rugosidad de Manning, a través del empleo de un modelo hidrodinámico completo en diferencias finitas para riego con surcos cerrados que resuelve las ecuaciones de Saint-Venant. Se muestran los resultados obtenidos en tres ensayos realizados en un surco cerrado de 50 m y, en un apéndice, el ajuste de la curva de avance en un surco cerrado de 150 m. Se concluye que el modelo numérico es aceptable para reproducir las tres fases del riego con surcos cerrados (avance, llenado y receso), por lo que puede ser empleado en el proceso de diseño para riego con surcos cerrados.Vázquez Fernández, E.; Gracia Sánchez, J. (1998). Calibración de parámetros de infiltración y rugosidad con un modelo numérico para riego con surcos cerrados. Ingeniería del Agua. 5(3):11-16. https://doi.org/10.4995/ia.1998.2761SWORD111653Bautista, E. y Wallender W. W. (1992) Hydrodynamic Furrow Irrigation Model with Specified Space Steps. of Irrigation and Drainage Engineering, Vol. 118, No. 3.Bautista, E. y Wallender W. W. (1993) Reliability of Optimized Furrow-Infiltracion Parameters. J. of Irrigation and Drainage Engineering, Vol. 119, No. 5.Chu, S. T. (1978) Infiltration During an Unsteady Rain. Water Resources Research. Vol. 14, No. 3.Elliot, R. L., Walker W. R. y Skogerboe G. B. (1982) Zero-Inertia Modeling of Furrow Irrigation Advance. J. of the Irrigation and Drainage Division, ASCE, Vol. 108, No. IR3.Juana, L. y Losada A. (1994) Semejanza Hidrodinámica en Riegos por Superficie. Ingeniería del Agua, Vol. 1, No. 1, Universidad Politécnica de Valencia.Rendón, P. L, Fuentes R. C. y Magaña S. G. (1995) Diseño Simplificado del Riego por Gravedad. Memorias del VI Congreso Nacional de Irrigación, Chapingo, México.Sánchez, J. L. y Fuentes O. A. (1992) Posibilidades de Incrementar la Eficiencia del Riego por Surcos. Informe Interno del Instituto de Ingeniería, UNAM.Schmitz, G H. and Seus G. J. (1992) Mathematical Zero-Inertia Modeling of Surface Irrigation: Advance n Furrows. J. of Irrigation and Drainage Engineering, Vol. 118, No. 1.Vázquez, E. (1994) Calibración de un Modelo Hidrodinámico para Riego por Surcos y Aplicaciones al étodo de Corte Posterior. Revista de Ingeniería, Vol. XIV, No. 4, UNAM.Wallender, W. W. y Rayej M. (1990) Shooting Method for Saint-Venant Equations of Furrow Irrigation. J. of Irrigation and Drainage Engineering, Vol. 116, No. 1.Wylie, E. B. and Streeter V. L. (1978) Fluid Transients. McGraw-Hill.Yu, F. X. y Singh V. P. (1990) Analytical Model for Furrow Irrigation. J. of Irrigation and Drainage Engineering, Vol. 116, No.
Modelo de simulación de sistemas de drenaje operados por bombeo
[ES] Se describe un modelo matemático que simula el funcionamiento de sistemas de drenaje operados por bombeo teniendo en cuenta la forma de trabajo de las bombas, según sus curvas de operación y el flujo transitorio en los conductos del sistema. Se comentan las posibles formas de utilizar el modelo en la solución de algunos problemas.Sánchez Bribiesca, JL.; Fuentes Maníes, ÓA.; Gracia Sánchez, J. (1994). Modelo de simulación de sistemas de drenaje operados por bombeo. Ingeniería del Agua. 1(3):19-30. https://doi.org/10.4995/ia.1994.2641SWORD193013Dolz J. y Gómez M. (1994) Problemática del drenaje de aguas pluviales en zonas urbanas y del estudio hidráulico de las redes de colectores. Ingeniería del Agua Vol 1. No 1, España.Sánchez B. J.L. y Fuentes M. O.A. (1966) Método alternativo para la evaluación de efectos transitorios en canales. Publicación No 46 de la Comisión Federal de Electricidad, México.Sánchez B. J.L, Fuentes M. O.A. y Gracia S.J. 0(1994) Diseño hidráulico de sistemas de drenaje operados por bombeo. Publicación interna del Instituto de Ingeniería, UNAM, México
Flood Risk Assessment in Housing under an Urban Development Scheme Simulating Water Flow in Plains
Floods are increasingly occurring around the world more often, this implies analysing the risks connected to both human health and the environment, and to infrastructure and properties. The objective is to establish areas susceptible to flooding and their impact on the population through the effects on the unit of analysis “housing”. To simulate the floods and map the affected areas, the FluBiDi 2D model was used. Two conditions for one urban zone analysed within the Mexico Valley were compared: (a) with the current hydraulic infrastructure and (b) with the application of rectification of channels. The available information was the discharge getting into the catchment and the total of homes in 2015. Projections for 20-year and 50-year planning horizon were considered, and for the 50 years, an evaluation of a non-structural measure was applied. Results show that under the current infrastructure, the flood simulated had a flow depth of 20 cm, decreasing to 5 cm average with rectification of channels, and a decrement of 45% of the cost of housing risk. Applying the both structural and non-structural measures, the cost of vulnerable housing was reduced until 94%, thus, this a trustworthy tool for decision-making in urban developments
Hidrogeles estructurados para aplicaciones biomédicas
Este Trabajo Fin de Grado tiene como objetivo la preparación de hidrogeles robustos con posibles aplicaciones biomédicas, compuestos por un polímero Tiol-Acrilato con cadenas de PEG reticulado y de laponita como nanoarcilla.El trabajo se ha llevado a cabo en dos partes, en primer lugar, preparación de hidrogeles nanocompuestos con una estructura híbrida orgánica-inorgánica, para seguidamente estudiar sus propiedades, su procesado y su comportamiento en condiciones fisiológicas relevantes.La primera parte supone llevar a cabo un proceso de optimización para conseguir un método de preparación sencillo, escalable y reproducible. Con el proceso óptimo se han preparado hidrogeles con distintas concentraciones de laponita, siendo este uno de los factores más influyentes en las propiedades de los materiales obtenidos.Las propiedades relevantes que se van a determinar para valorar la utilidad de los hidrogeles preparados serán sus propiedades mecánicas y capacidad de hinchamiento en función de la concentración de laponita y de la temperatura.<br /
Vibrational and thermal characterization of seeds, pulp, leaves and seed oil of Rosa rubiginosa
Rosa rubiginosa L. seed oil has been studied for its application in skin care products, but the chemical nature of seeds, pulp and even leaves, apart from that of oil, is also relevant with a view to the application of this weed for biodiesel production. All these vegetal materials were studied by infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) for characterisation purposes. FTIR bands at 3005, 2924, 1740, 1654 and 1456 cm-1 were used to estimate the iodine index, suitable for biofuels, and the oxidation stability degree. From the viewpoint of the thermal stability, both the seed oil (for which pyrolysis occurs at 462°C), the raw seeds and the rosehip pulp (with decomposition temperatures of 373°C and 333°C, respectively) showed potential as a biomass feedstock for conversion into biofuels. Caracterización térmica y vibracional de las semillas, pulpa, hojas y aceite de semillas de Rosa rubiginosa. El aceite de semillas de R. rubiginosa L. ha sido estudiado para su aplicación en productos para el cuidado de la piel, pero la naturaleza química de las semillas, pulpa y hojas, además de la del aceite, también es importante con miras a la aplicación de esta mala hierba para la producción de biodiesel. Los materiales vegetales mencionados se han estudiado mediante espectroscopía infrarroja (FTIR) y calorimetría diferencial de barrido (DSC) con fines de caracterización. Las bandas del espectro infrarrojo en 3005, 2924, 1740, 1654 y 1456 cm-1 han sido utilizadas para estimar el índice de yodo, adecuado para los biocombustibles, y el grado de estabilidad a la oxidación. Desde el punto de vista de la estabilidad térmica, tanto el aceite de semillas (para el que la pirólisis se produce a 462ºC) como las semillas crudas y la pulpa (con temperaturas de descomposición de 373°C y 333°C, respectivamente) mostraron potencial como materia prima de biomasa para su conversión en biocombustibles
Armeria maritima (Mill.) Willd. Flower hydromethanolic extract for Cucurbitaceae fungal diseases control
The cliff rose (Armeria maritima), like other halophytes, has a phenolics-based antioxidant system that allows it to grow in saline habitats. Provided that antioxidant properties are usually accompanied by antimicrobial activity, in this study we investigated the phytochemicals present in a hydromethanolic extract of A. maritima flowers and explored its antifungal potential. The main phytocompounds, identified by gas chromatography–mass spectrometry, were: hexadecanoic acid, octadecanoic acid, 9-octadecenoic acid, 3-(3,4-dihydroxy-phenyl)-acrylic acid ethyl ester, and benzeneacetaldehyde. The antifungal activity of the extract and its main constituents—alone and in combination with chitosan oligomers—was tested against six pathogenic taxa associated with soil-borne diseases of plant hosts in the family Cucurbitaceae: Fusarium equiseti, F. oxysporum f. sp. niveum, Macrophomina phaseolina, Neocosmospora falciformis, N. keratoplastica, and Sclerotinia sclerotiorum. In in vitro tests, EC90 effective concentrations in the 166−865 μg·mL−1 range were obtained for the chitosan oligomers–A. maritima extract conjugate complexes, lower than those obtained for fosetyl-Al and azoxystrobin synthetic fungicides tested for comparison purposes, and even outperforming mancozeb against F. equiseti. In ex situ tests against S. sclerotiorum conducted on artificially inoculated cucumber slices, full protection was achieved at a dose of 250 μg·mL−1. Thus, the reported results support the valorization of A. maritima as a source of biorationals for Cucurbitaceae pathogens protection, suitable for both organic and conventional agriculture
Alginate–Chitosan Membranes for the Encapsulation of Lavender Essential Oil and Development of Biomedical Applications Related to Wound Healing
Funding Information: This research was funded by the project Ref. SBPLY/17/180501/000311 from the Consejería de Educación, Cultura y Deportes of Junta de Comunidades de Castilla-La Mancha. It has also been possible to carry out this work thanks to funding from the “Call for grants to carry out pre-doctoral stays in foreign Universities and Research Centres for UCLM doctoral students—Co-funded by the Collaboration Agreement between the University of Castilla-La Mancha and Banco Santander”. This work has also received funding from the European Union’s Horizon 2020—European Research Council (ERC)—under grant agreement No ERC-2016-CoG 725034. Funding Information: We gratefully acknowledge funding from the Consejería de Educación, Cultura y Deportes of Junta de Comunidades de Castilla La Mancha provided for this project. This work was supported by the Associate Laboratory for Green Chemistry (LAQV), which is financed by national funds from FCT/MCTES (UIDB/50006/2020 and UIDP/50006/2020). This work was also supported by Filipe Oliveira’s and Joana Pereira’s grants, 2021.07780.BD and 2022.13700.BD, respectively. Publisher Copyright: © 2023 by the authors.Biopolymers such as chitosan (CHT) or alginate (ALG) are among the most prominent for health-related applications due to their broad bioactivity. Their combination for the preparation of membranes is hereby proposed as an application for wound healing with the incorporation of lavender essential oil (LEO), widely known for its antioxidant and antimicrobial properties. The preparation of CHT, CHT + LEO, ALG, ALG + LEO, and CHT/ALG + LEO membranes was accomplished, and its composition was analyzed using Fourier Transform Infrared Spectroscopy (FTIR). The water absorption capacity and oil release profile of the membranes revealed higher water uptake capacity when a lower LEO release was obtained. The combined CHT/ALG + LEO film showed a water uptake percentage of 638% after 48 h and a maximum LEO release concentration of 42 mg/L. Cytotoxicity and biocompatibility of the prepared membranes were studied using a HaCaT cell line, with an assessment of cell viability regarding film leachables, DNA quantification, and DAPI-phalloidin staining. The results revealed that the indirect contact of the prepared membranes via its leachables does not compromise cell viability, and upon direct contact, cells do not adhere or proliferate on the surface of the membranes. Moreover, the CHT/ALG + LEO membrane increases cell proliferation, making it suitable for applications in wound healing.publishersversionpublishe
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