Experiencia con la herramienta de virtualización VNUML para la enseñanza de redes de computadores

La virtualización permite disponer y configurar infraestructuras de red con un coste asumible para un laboratorio y, a diferencia de los simuladores, muestra un comportamiento real del sistema. Este artículo presenta la metodología que seguimos en la asignatura de Redes de la Facultad de Informática de la Universidad de Murcia para la enseñanza práctica de conceptos tales como encaminamiento, movilidad IP, balanceo de carga y alta disponibilidad por medio de la herramienta de virtualización de código abierto VNUML. Para mostrar estos conceptos hemos añadido diversas utilidades al sistema de ficheros utilizado en VNUML. Gracias a estas herramientas, los alumnos han podido mejorar el aprendizaje de estos conceptos como lo refutan las encuestas realizadas.Peer Reviewe

Evaluacion agronomica de los sustratos de cultivo

La finalidad de cualquier buen medio de cultivo es producir una planta decalidad en el más corto período de tiempo, con los más bajos costes de producción. En adición, la obtención y la eliminación del sustrato, una vez haya sido utilizado, no deberían provocar un impacto medioambiental de importancia. La evaluación agronómica de los sustratos de cultivo pasa por diferentes etapas. En primer lugar, debería procederse a la caracterización de los materiales, determinándose sus propiedades físicas, físico-químicas, químicas y biológicas. A continuación, dichas propiedades deberían estudiarse críticamente, comparándolas con las del sustrato "ideal". Posteriormente, y en aquellos casos en que las propiedades del material se desvíen significativamente de los valores óptimos recomendados, debería procederse a mejorar, de modo sencillo, dichas propiedades. Finalmente, deberían llevarse a cabo ensayos de crecimiento vegetal: ensayos en semilleros, ensayos en maceta, ensayos en condiciones de hidroponía y ensayos de enraizamiento de estacas. La realización de los ensayos de crecimiento bajo condiciones particulares (aire libre / invernadero, época del año, calidad de las aguas de riego, etc.) exige: 1) seleccionar las especies vegetales a utilizar como planta testigo, 2) diseñar las estrategias de manejo de los sustratos durante el ciclo de cultivo, especialmente los contenedores, el riego y la fertilización, y, 3) evaluar el crecimiento vegetativo y el desarrollo reproductivo mediante el control de los parámetros más adecuados a la hora de estimar la respuesta vegetal. Estos ensayos de crecimiento deberían incluir también sustratos comerciales como control de referencia

Computational Determination of Air Valves Capacity Using CFD Techniques

[EN] The analysis of transient flow is necessary to design adequate protection systems that support the oscillations of pressure produced in the operation of motor elements and regulation. Air valves are generally used in pressurized water pipes to manage the air inside them. Under certain circumstances, they can be used as an indirect control mechanism of the hydraulic transient. Unfortunately, one of the major limitations is the reliability of information provided by manufacturers and vendors, which is why experimental trials are usually used to characterize such devices. The realization of these tests is not simple since they require an enormous volume of previously stored air to be used in such experiments. Additionally, the costs are expensive. Consequently, it is necessary to develop models that represent the behaviour of these devices. Although computational fluid dynamics (CFD) techniques cannot completely replace measurements, the amount of experimentation and the overall cost can be reduced significantly. This work approaches the characterization of air valves using CFD techniques, including some experimental tests to calibrate and validate the results. A mesh convergence analysis was made. The results show how the CFD models are an efficient alternative to represent the behavior of air valves during the entry and exit of air to the system, implying a better knowledge of the system to improve it.This research was funded by the Program Fondecyt Regular, grant number 1180660.García-Todolí, S.; Iglesias Rey, PL.; Mora Melia, D.; Martínez-Solano, FJ.; Fuertes-Miquel, VS. (2018). Computational Determination of Air Valves Capacity Using CFD Techniques. Water. 10(10):1-16. https://doi.org/10.3390/w10101433S1161010Liou, C. P., & Hunt, W. A. (1996). Filling of Pipelines with Undulating Elevation Profiles. Journal of Hydraulic Engineering, 122(10), 534-539. doi:10.1061/(asce)0733-9429(1996)122:10(534)Zhou, F., Hicks, F. E., & Steffler, P. M. (2002). Transient Flow in a Rapidly Filling Horizontal Pipe Containing Trapped Air. Journal of Hydraulic Engineering, 128(6), 625-634. doi:10.1061/(asce)0733-9429(2002)128:6(625)Laanearu, J., Annus, I., Koppel, T., Bergant, A., Vučković, S., Hou, Q., … van’t Westende, J. M. C. (2012). Emptying of Large-Scale Pipeline by Pressurized Air. Journal of Hydraulic Engineering, 138(12), 1090-1100. doi:10.1061/(asce)hy.1943-7900.0000631Apollonio, C., Balacco, G., Fontana, N., Giugni, M., Marini, G., & Piccinni, A. (2016). Hydraulic Transients Caused by Air Expulsion During Rapid Filling of Undulating Pipelines. Water, 8(1), 25. doi:10.3390/w8010025Zhou, F., Hicks, F. E., & Steffler, P. M. (2002). Observations of Air–Water Interaction in a Rapidly Filling Horizontal Pipe. Journal of Hydraulic Engineering, 128(6), 635-639. doi:10.1061/(asce)0733-9429(2002)128:6(635)Vasconcelos, J. G., Wright, S. J., & Roe, P. L. (2006). Improved Simulation of Flow Regime Transition in Sewers: Two-Component Pressure Approach. Journal of Hydraulic Engineering, 132(6), 553-562. doi:10.1061/(asce)0733-9429(2006)132:6(553)Li, J., & McCorquodale, A. (1999). Modeling Mixed Flow in Storm Sewers. Journal of Hydraulic Engineering, 125(11), 1170-1180. doi:10.1061/(asce)0733-9429(1999)125:11(1170)Ramezani, L., Karney, B., & Malekpour, A. (2015). The Challenge of Air Valves: A Selective Critical Literature Review. Journal of Water Resources Planning and Management, 141(10), 04015017. doi:10.1061/(asce)wr.1943-5452.0000530Stephenson, D. (1997). Effects of Air Valves and Pipework on Water Hammer Pressures. Journal of Transportation Engineering, 123(2), 101-106. doi:10.1061/(asce)0733-947x(1997)123:2(101)Bianchi, A., Mambretti, S., & Pianta, P. (2007). Practical Formulas for the Dimensioning of Air Valves. Journal of Hydraulic Engineering, 133(10), 1177-1180. doi:10.1061/(asce)0733-9429(2007)133:10(1177)De Martino, G., Fontana, N., & Giugni, M. (2008). Transient Flow Caused by Air Expulsion through an Orifice. Journal of Hydraulic Engineering, 134(9), 1395-1399. doi:10.1061/(asce)0733-9429(2008)134:9(1395)Bhosekar, V. V., Jothiprakash, V., & Deolalikar, P. B. (2012). Orifice Spillway Aerator: Hydraulic Design. Journal of Hydraulic Engineering, 138(6), 563-572. doi:10.1061/(asce)hy.1943-7900.0000548Iglesias-Rey, P. L., Fuertes-Miquel, V. S., García-Mares, F. J., & Martínez-Solano, J. J. (2014). Comparative Study of Intake and Exhaust Air Flows of Different Commercial Air Valves. Procedia Engineering, 89, 1412-1419. doi:10.1016/j.proeng.2014.11.467Martins, N. M. C., Soares, A. K., Ramos, H. M., & Covas, D. I. C. (2016). CFD modeling of transient flow in pressurized pipes. Computers & Fluids, 126, 129-140. doi:10.1016/j.compfluid.2015.12.002Zhou, L., Liu, D., & Ou, C. (2011). Simulation of Flow Transients in a Water Filling Pipe Containing Entrapped Air Pocket with VOF Model. Engineering Applications of Computational Fluid Mechanics, 5(1), 127-140. doi:10.1080/19942060.2011.11015357Davis, J. A., & Stewart, M. (2002). Predicting Globe Control Valve Performance—Part I: CFD Modeling. Journal of Fluids Engineering, 124(3), 772-777. doi:10.1115/1.1490108Stephens, D., Johnson, M. C., & Sharp, Z. B. (2012). Design Considerations for Fixed-Cone Valve with Baffled Hood. Journal of Hydraulic Engineering, 138(2), 204-209. doi:10.1061/(asce)hy.1943-7900.0000496Romero-Gomez, P., Ho, C. K., & Choi, C. Y. (2008). Mixing at Cross Junctions in Water Distribution Systems. I: Numerical Study. Journal of Water Resources Planning and Management, 134(3), 285-294. doi:10.1061/(asce)0733-9496(2008)134:3(285)Austin, R. G., Waanders, B. van B., McKenna, S., & Choi, C. Y. (2008). Mixing at Cross Junctions in Water Distribution Systems. II: Experimental Study. Journal of Water Resources Planning and Management, 134(3), 295-302. doi:10.1061/(asce)0733-9496(2008)134:3(295)Ho, C. K. (2008). Solute Mixing Models for Water-Distribution Pipe Networks. Journal of Hydraulic Engineering, 134(9), 1236-1244. doi:10.1061/(asce)0733-9429(2008)134:9(1236)Huang, J., Weber, L. J., & Lai, Y. G. (2002). Three-Dimensional Numerical Study of Flows in Open-Channel Junctions. Journal of Hydraulic Engineering, 128(3), 268-280. doi:10.1061/(asce)0733-9429(2002)128:3(268)Weber, L. J., Schumate, E. D., & Mawer, N. (2001). Experiments on Flow at a 90° Open-Channel Junction. Journal of Hydraulic Engineering, 127(5), 340-350. doi:10.1061/(asce)0733-9429(2001)127:5(340)Chanel, P. G., & Doering, J. C. (2008). Assessment of spillway modeling using computational fluid dynamics. Canadian Journal of Civil Engineering, 35(12), 1481-1485. doi:10.1139/l08-094Li, S., Cain, S., Wosnik, M., Miller, C., Kocahan, H., & Wyckoff, R. (2011). Numerical Modeling of Probable Maximum Flood Flowing through a System of Spillways. Journal of Hydraulic Engineering, 137(1), 66-74. doi:10.1061/(asce)hy.1943-7900.0000279Castillo, L., García, J., & Carrillo, J. (2017). Influence of Rack Slope and Approaching Conditions in Bottom Intake Systems. Water, 9(1), 65. doi:10.3390/w9010065Regueiro-Picallo, M., Naves, J., Anta, J., Puertas, J., & Suárez, J. (2016). Experimental and Numerical Analysis of Egg-Shaped Sewer Pipes Flow Performance. Water, 8(12), 587. doi:10.3390/w812058

KIR+ CD8+ T Lymphocytes in Cancer Immunosurveillance and Patient Survival: Gene Expression Profiling

Killer-cell immunoglobulin-like receptors (KIR) are molecules expressed by the most important cells of the immune system for cancer immune vigilance, natural killer (NK) and effector T cells. In this manuscript we study the role that cytotoxic CD8+ T cells expressing KIR receptors could play in cancer immune surveillance. With this objective, frequencies of different KIR+ CD8+ T cell subsets are correlated with the overall survival of patients with melanoma, ovarian and bladder carcinomas. In addition, the gene expression profile of KIR+ CD8+ T cell subsets related to the survival of patients is studied with the aim of discovering new therapeutic targets, so that the outcome of patients with cancer can be improved. Killer-cell immunoglobulin-like receptors (KIR) are expressed by natural killer (NK) and effector T cells. Although KIR+ T cells accumulate in oncologic patients, their role in cancer immune response remains elusive. This study explored the role of KIR+CD8+ T cells in cancer immunosurveillance by analyzing their frequency at diagnosis in the blood of 249 patients (80 melanomas, 80 bladder cancers, and 89 ovarian cancers), their relationship with overall survival (OS) of patients, and their gene expression profiles. KIR2DL1+ CD8+ T cells expanded in the presence of HLA-C2-ligands in patients who survived, but it did not in patients who died. In contrast, presence of HLA-C1-ligands was associated with dose-dependent expansions of KIR2DL2/S2+ CD8+ T cells and with shorter OS. KIR interactions with their specific ligands profoundly impacted CD8+ T cell expression profiles, involving multiple signaling pathways, effector functions, the secretome, and consequently, the cellular microenvironment, which could impact their cancer immunosurveillance capacities. KIR2DL1/S1+ CD8+ T cells showed a gene expression signature related to efficient tumor immunosurveillance, whereas KIR2DL2/L3/S2+CD8+ T cells showed transcriptomic profiles related to suppressive anti-tumor responses. These results could be the basis for the discovery of new therapeutic targets so that the outcome of patients with cancer can be improved

Plants Probiotics as a Tool to Produce Highly Functional Fruits: The Case of Phyllobacterium and Vitamin C in Strawberries

10 páginas, 1 tabla, 1 figuraThe increasing interest in the preservation of the environment and the health of consumers is changing production methods and food consumption habits. Functional foods are increasingly demanded by consumers because they contain bioactive compounds involved in health protection. In this sense biofertilization using plant probiotics is a reliable alternative to the use of chemical fertilizers, but there are few studies about the effects of plant probiotics on the yield of functional fruits and, especially, on the content of bioactive compounds. In the present work we reported that a strain of genus Phyllobacterium able to produce biofilms and to colonize strawberry roots is able to increase the yield and quality of strawberry plants. In addition, the fruits from plants inoculated with this strain have significantly higher content in vitamin C, one of the most interesting bioactive compounds in strawberries. Therefore the use of selected plant probiotics benefits the environment and human health without agronomical losses, allowing the production of highly functional foods.This work was granted by “Junta de Castilla y León” (Regional Government, Grant SA183A11-2) and MINECO (Central Government, Grant AGL2011-29227). Paula García-Fraile is recipient of a postdoctoral researcher contract from Academy of Sciences of the Czech Republic. José David Flores-Félix was supported by a fellowship of Salamanca University. Marta Marcos García was supported by a fellowship of Fundación Miguel Casado San José. Luís R. Silva is grateful to the financial support from the European Union (FEDER funds through COMPETE) and National Funds (FCT, Fundação para a Ciência e Tecnologia) through project Pest-C/EQB/LA0006/2013 and from the European Union (FEDER funds) under the framework of QREN through Project NORTE-07-0124-FEDER- 000069.Peer reviewe

Experiencia con la herramienta de virtualización VNUML para la enseñanza de redes de computadores

La virtualización permite disponer y configurar infraestructuras de red con un coste asumible para un laboratorio y, a diferencia de los simuladores, muestra un comportamiento real del sistema. Este artículo presenta la metodología que seguimos en la asignatura de Redes de la Facultad de Informática de la Universidad de Murcia para la enseñanza práctica de conceptos tales como encaminamiento, movilidad IP, balanceo de carga y alta disponibilidad por medio de la herramienta de virtualización de código abierto VNUML. Para mostrar estos conceptos hemos añadido diversas utilidades al sistema de ficheros utilizado en VNUML. Gracias a estas herramientas, los alumnos han podido mejorar el aprendizaje de estos conceptos como lo refutan las encuestas realizadas.Este trabajo ha sido parcialmente financiado por el “Programa de Ayuda a los Grupos de Excelencia de la Fundación Séneca 04552/GERM/06” y por el proyecto CICYT TIN2008-06441-C02-02

MALDI-TOF Mass Spectrometry Is a Fast and Reliable Platform for Identification and Ecological Studies of Species from Family Rhizobiaceae

Family Rhizobiaceae includes fast growing bacteria currently arranged into three genera, Rhizobium, Ensifer and Shinella, that contain pathogenic, symbiotic and saprophytic species. The identification of these species is not possible on the basis of physiological or biochemical traits and should be based on sequencing of several genes. Therefore alternative methods are necessary for rapid and reliable identification of members from family Rhizobiaceae. In this work we evaluated the suitability of Matrix-Assisted Laser Desorption Ionization-Time-of-Flight Mass Spectrometry (MALDI-TOF MS) for this purpose. Firstly, we evaluated the capability of this methodology to differentiate among species of family Rhizobiaceae including those closely related and then we extended the database of MALDI Biotyper 2.0 including the type strains of 56 species from genera Rhizobium, Ensifer and Shinella. Secondly, we evaluated the identification potential of this methodology by using several strains isolated from different sources previously identified on the basis of their rrs, recA and atpD gene sequences. The 100% of these strains were correctly identified showing that MALDI-TOF MS is an excellent tool for identification of fast growing rhizobia applicable to large populations of isolates in ecological and taxonomic studies

Modalidades productivas en el pimiento de invernadero y su incidencia en la comercialización

Se comenta, en principio, la situación económica del pimiento y cual es su posición competitiva. Actualmente la producción y comercialización de pimiento se encuentran muy condicionadas en aspectos económicos, medioambientales, y de la calidad y seguridad alimentaria, que se pueden sintetizar en: Unos costes de producción elevados; los mercados se encuentran muy abastecidos, con riesgo de saturación y descenso de los precios; dominio de la gran distribución en la comercialización; Política Agraria Comunitaria (PAC) a favor del medioambiente y de la biodiversidad; sensibilización de los consumidores por la sanidad de los productos y obligación de cumplir con la trazabilidad. Aunque España ha competido favorablemente con otros países europeos, en las producciones hortofrutícolas de invernadero, deberá en el futuro tener en cuenta a los países mediterráneos, más aún, después del Acuerdo Euromediterráneo. En el trabajo se analizan las características de la producción de pimiento en invernadero, centradas en el cultivo en sustrato, la producción integrada y la producción ecológica. Una vez efectuada la valoración económica de cada modalidad productiva, se establecen una serie de consideraciones sobre la incidencia de cada una de ellas en la comercialización

Aislamiento de un extracto de BMP y estudio anatomopatológico del fenómeno de inducción ósea tras su implante en defectos óseos

El objetivo del presente trabajo fue determinar el potencial osteogénico de la proteína morfogenética ósea (BMP) en la reparación de grandes defectos diafisarios. Además, se investiga la acción coadyuvante de la fibronectina (FN). La BMP fue extraída a partir de hueso cortical bovino. Se utilizaron un total de 108 ratas Sprague Dawley. En cada animal, se resecó un segmento de diáfisis femoral de 1.5 cm, siendo inmovilizado el defecto óseo con una aguja en omega. Se rellenó el defecto implantando 25 mg de BMP con o sin 0.5 mg de FN en una cápsula de gelatina (36 animales en ambos grupos). Los resultados se compararon con los obtenidos en otro grupo (36 animales) en el que sólo se implantó FN que sirvió como grupo control. El proceso de reparación se evaluó mediante métodos histológicos y ultraestructurales. La aparición del fenómeno de inducción ósea con reconstrucción del defecto óseo fue mayor en el grupo con implante de BMP más FN (23 animales, 64%) que en el grupo en el que sólo se implantó BMP (20 animales, 56%). Ningún animal del grupo control manifestaba signos de inducción ósea.The aim of the present work was to evaluate the osteogenic potential of Bone Morphogenetic Protein (BMP) for reparation of large segmental bone defects. In addition, the coadjuvant efect of fibronectin (FN) was investigated. BMP was partially purified from bovine cortical bone. A total of 108 Sprague Dawley rats were used in the experiment. Diaphyseal segments of the femur (1.5 cm) were removed in each animal, manteinant the bone defect with a wire. A gelatine capsula containing 25 mg of BMP without or with 0.5 mg of FN, were implanted into the bone defect (36 animal in each group). Results were compared to those obtained in a control group (36 animals) in which FN alone was implanted. The bone repair process was assessed by histologic and ultrastructural methods. Bone induction with reconstruction of the defect was found more of ten in the group with both BMP and FN implanted (23 animals, 64%) than in the group with BMP implant alone (20 animals, 56%). Animals of the control group showed no bone induction. The results suggest that BMP augments the capacity of the host bed to sucessfully regenerate large segmental bone defects. FN seens to increase bone induction. This protein migth stabilize BMP locally improving contact between BMP and the surrounding cells

Mouse p53-deficient cancer models as platforms for obtaining genomic predictors of human cancer clinical outcomes

Mutations in the TP53 gene are very common in human cancers, and are associated with poor clinical outcome. Transgenic mouse models lacking the Trp53 gene or that express mutant Trp53 transgenes produce tumours with malignant features in many organs. We previously showed the transcriptome of a p53-deficient mouse skin carcinoma model to be similar to those of human cancers with TP53 mutations and associated with poor clinical outcomes. This report shows that much of the 682-gene signature of this murine skin carcinoma transcriptome is also present in breast and lung cancer mouse models in which p53 is inhibited. Further, we report validated gene-expression-based tests for predicting the clinical outcome of human breast and lung adenocarcinoma. It was found that human patients with cancer could be stratified based on the similarity of their transcriptome with the mouse skin carcinoma 682-gene signature. The results also provide new targets for the treatment of p53-defective tumours