Efficient exploration of availability models guided by failure distances

Recently, a method to bound the steady-state availability using the failure distance concept has been proposed. In this paper we refine that method by introducing state space exploration techniques. In the methods proposed here, the state space is incrementally generated based on the contributions to the steady-state availability band of the states in the frontier of the currently generated state space. Several state space exploration algorithms are evaluated in terms of bounds quality and memory and CPU time requirements. The more efficient seems to be a waved algorithm which expands transition groups. We compare our new methods with the method based on the failure distance concept without state exploration and a method proposed by Souza e Silva and Ochoa which uses state space exploration but does not use the failure distance concept. Using typical examples we show that the methods proposed here can be significantly more efficient than any of the previous methods.Postprint (published version

Principios para basar las técnicas de mantenimiento industrial en relación a la eficiencia energética

[ES] La energía supone un coste que puede representar una fracción muy elevada de los costes de producción dependiendo del sector de que se trate. Esto sugiere una revisión o superación, siquiera parcial, de los sistemas de mantenimiento industrial, introduciendo la variable de la eficiencia energética, que analizando cada una de las partes por separado del conjunto industrial o todo el sistema de forma global, nos permita conseguir el máximo de operatividad en el proceso industrial (aumentando el ciclo de vida útil, disminuir las paradas, eliminar los sucesos no deseados, etc.), así como la máxima eficiencia energética que redundará en el menor coste de energía para el proceso. Este artículo, trata de definir los cauces básicos por los que debe incidir los modelos de mantenimiento teniendo en cuenta la variable eficiencia energética.Cárcel Carrasco, FJ.; Peñalvo-López, E.; Cárcel Carrasco, J. (2017). Principios para basar las técnicas de mantenimiento industrial en relación a la eficiencia energética. Mantenimiento en Latinoamérica. 9(6):18-22. http://hdl.handle.net/10251/102609S18229

A proteomic approach to the myocardium of hypertensive-diabetic rats

Comunicaciones a congreso

Virtual versus Real Nuclear Compton Scattering in the Delta(1232) Region

In this paper we calculate the cross section for Virtual Compton Scattering off nuclei in the delta resonance region. We also calculate the background for the process from Coherent Bremsstrahlung in nuclei and explore the regions where the Virtual Compton Scattering cross section dominates. The study also shows that it is possible to extract the cross section for Real Compton Scattering from the Virtual Compton one in a wide range of scattering angles.Comment: latex , 11 pages, ps.gz file, 16 figure

Anthropometric profiles in table tennis players: Analysis of sex, age, and ranking

Table tennis has recently evolved towards a more spectacular sport increasing match-play demands and the intensity and speed of actions by regulations and equipment modification. Since these changes can alter the body composition and performance, this study aimed to analyze the differences in anthropometric attributes of 495 table tennis players (288 men, 207 women) according to sex, age, and ranking. Players were classified according to sex, age categories (Senior, Under-18, Under-15, Under 13, and Under 11), and ranking position. Anthropometry measurements included eight skinfolds’ thicknesses (biceps brachii, triceps, subscapular, iliac crest, supraspinal, abdominal, thigh, and medial calf), four girths (biceps brachii relaxed and contracted, thigh, and calf), and three breadths (biepicondylar femur, biepicondylar humerus, and bistiloyd wrist) to determine fat mass, lean mass, bone, cross sectional area (CSA) for arm, leg, and thigh, and somatotype. Results revealed that table tennis players presented differences in body mass composition, anthropometry, and somatotype according to sex and age category and ranking. It seems confirmed that regular table tennis practice during the childhood is associated with a healthy body composition status, that appears to be maintained across older ages if keeping the practice. Senior table tennis players showed a fat mass <20% and lean mass ~45% in men and ~37% in women. A new contribution is that higher lean mass in the upper limbs was associated with higher ranking position (i.e., better performance), endomorphic somatotypes were negative related to performance, and ectomorphic profiles seems more effective, which suggest the potential influence of morphologic changes in table tennis competition performance

Direct visualization of the native structure of viroid RNAs at single-molecule resolution by atomic force microscopy

[EN] Viroids are small infectious, non-protein-coding circular RNAs that replicate independently and, in some cases, incite diseases in plants. They are classified into two families: Pospiviroidae, composed of species that have a central conserved region (CCR) and replicate in the cell nucleus, and Avsunviroidae, containing species that lack a CCR and whose multimeric replicative intermediates of either polarity generated in plastids self-cleave through hammerhead ribozymes. The compact, rod-like or branched, secondary structures of viroid RNAs have been predicted by RNA folding algorithms and further examined using different in vitro and in vivo experimental techniques. However, direct data about their native tertiary structure remain scarce. Here we have applied atomic force microscopy (AFM) to image at single-molecule resolution different variant RNAs of three representative viroids: potato spindle tuber viroid (PSTVd, family Pospiviroidae), peach latent mosaic viroid and eggplant latent viroid (PLMVd and ELVd, family Avsunviroidae). Our results provide a direct visualization of their native, three-dimensional conformations at 0 and 4 mM Mg2+ and highlight the role that some elements of tertiary structure play in their stabilization. The AFM images show that addition of 4 mM Mg2+ to the folding buffer results in a size contraction in PSTVd and ELVd, as well as in PLMVd when the kissing-loop interaction that stabilizes its 3D structure is preserved.This work was supported by the Spanish Ministerio de Economia y Competitividad (MINECO) grants BIO2016-79618-R (funded by EU under the FEDER programme) to C.B. and BFU2104-56812-P to R.F., as well as by the Comunidad de Madrid grant S2018/NMT-4349 to L.V. CIBERehd is funded by the Instituto de Salud Carlos III (ISCIII).Moreno, M.; Vázquez, L.; López Carrasco, A.; Martín-Gago, JA.; Flores Pedauye, R.; Briones, C. (2019). Direct visualization of the native structure of viroid RNAs at single-molecule resolution by atomic force microscopy. RNA Biology. 16(3):295-308. https://doi.org/10.1080/15476286.2019.1572436S295308163Diener, T. O. (2003). Discovering viroids — a personal perspective. Nature Reviews Microbiology, 1(1), 75-80. doi:10.1038/nrmicro736Flores, R., Hernández, C., Alba, A. E. M. de, Daròs, J.-A., & Serio, F. D. (2005). Viroids and Viroid-Host Interactions. Annual Review of Phytopathology, 43(1), 117-139. doi:10.1146/annurev.phyto.43.040204.140243Ding, B. (2009). The Biology of Viroid-Host Interactions. Annual Review of Phytopathology, 47(1), 105-131. doi:10.1146/annurev-phyto-080508-081927Zhang, Z., Qi, S., Tang, N., Zhang, X., Chen, S., Zhu, P., … Wu, Q. (2014). Discovery of Replicating Circular RNAs by RNA-Seq and Computational Algorithms. PLoS Pathogens, 10(12), e1004553. doi:10.1371/journal.ppat.1004553Serra, P., Messmer, A., Sanderson, D., James, D., & Flores, R. (2018). Apple hammerhead viroid-like RNA is a bona fide viroid: Autonomous replication and structural features support its inclusion as a new member in the genus Pelamoviroid. Virus Research, 249, 8-15. doi:10.1016/j.virusres.2018.03.001Hadidi, A., Barba, M., Hong, N., & Hallan, V. (2017). Apple Scar Skin Viroid. Viroids and Satellites, 217-228. doi:10.1016/b978-0-12-801498-1.00021-8Flores, R., Minoia, S., Carbonell, A., Gisel, A., Delgado, S., López-Carrasco, A., … Di Serio, F. (2015). Viroids, the simplest RNA replicons: How they manipulate their hosts for being propagated and how their hosts react for containing the infection. Virus Research, 209, 136-145. doi:10.1016/j.virusres.2015.02.027Hammann, C., & Steger, G. (2012). Viroid-specific small RNA in plant disease. RNA Biology, 9(6), 809-819. doi:10.4161/rna.19810Kovalskaya, N., & Hammond, R. W. (2014). Molecular biology of viroid–host interactions and disease control strategies. Plant Science, 228, 48-60. doi:10.1016/j.plantsci.2014.05.006Tsagris, E. M., Martínez de Alba, Á. E., Gozmanova, M., & Kalantidis, K. (2008). Viroids. Cellular Microbiology, 10(11), 2168-2179. doi:10.1111/j.1462-5822.2008.01231.xGrill, L. K., & Semancik, J. S. (1978). RNA sequences complementary to citrus exocortis viroid in nucleic acid preparations from infected Gynura aurantiaca. Proceedings of the National Academy of Sciences, 75(2), 896-900. doi:10.1073/pnas.75.2.896Branch, A. D., Benenfeld, B. J., & Robertson, H. D. (1988). Evidence for a single rolling circle in the replication of potato spindle tuber viroid. Proceedings of the National Academy of Sciences, 85(23), 9128-9132. doi:10.1073/pnas.85.23.9128Branch, A. D., & Robertson, H. D. (1984). A Replication Cycle for Viroids and Other Small Infectious RNA’s. Science, 223(4635), 450-455. doi:10.1126/science.6197756Daros, J. A., Marcos, J. F., Hernandez, C., & Flores, R. (1994). Replication of avocado sunblotch viroid: evidence for a symmetric pathway with two rolling circles and hammerhead ribozyme processing. Proceedings of the National Academy of Sciences, 91(26), 12813-12817. doi:10.1073/pnas.91.26.12813Feldstein, P. A., Hu, Y., & Owens, R. A. (1998). Precisely full length, circularizable, complementary RNA: An infectious form of potato spindle tuber viroid. Proceedings of the National Academy of Sciences, 95(11), 6560-6565. doi:10.1073/pnas.95.11.6560Daros, J.-A., & Flores, R. (2004). Arabidopsis thaliana has the enzymatic machinery for replicating representative viroid species of the family Pospiviroidae. Proceedings of the National Academy of Sciences, 101(17), 6792-6797. doi:10.1073/pnas.0401090101Flores, R., Gago-Zachert, S., Serra, P., Sanjuán, R., & Elena, S. F. (2014). Viroids: Survivors from the RNA World? Annual Review of Microbiology, 68(1), 395-414. doi:10.1146/annurev-micro-091313-103416Diener, T. O. (1989). Circular RNAs: relics of precellular evolution? Proceedings of the National Academy of Sciences, 86(23), 9370-9374. doi:10.1073/pnas.86.23.9370Ruiz-Mirazo, K., Briones, C., & de la Escosura, A. (2013). Prebiotic Systems Chemistry: New Perspectives for the Origins of Life. Chemical Reviews, 114(1), 285-366. doi:10.1021/cr2004844Flores, R., Serra, P., Minoia, S., Di Serio, F., & Navarro, B. (2012). Viroids: From Genotype to Phenotype Just Relying on RNA Sequence and Structural Motifs. Frontiers in Microbiology, 3. doi:10.3389/fmicb.2012.00217Steger, G., & Perreault, J.-P. (2016). Structure and Associated Biological Functions of Viroids. Advances in Virus Research, 141-172. doi:10.1016/bs.aivir.2015.11.002Diener, T. O. (1972). Potato spindle tuber viroid. Virology, 50(2), 606-609. doi:10.1016/0042-6822(72)90412-6Gross, H. J., Domdey, H., Lossow, C., Jank, P., Raba, M., Alberty, H., & Sänger, H. L. (1978). Nucleotide sequence and secondary structure of potato spindle tuber viroid. Nature, 273(5659), 203-208. doi:10.1038/273203a0Gast, F.-U., Kempe, D., Spieker, R. L., & Sänger, H. L. (1996). Secondary Structure Probing of Potato Spindle Tuber Viroid (PSTVd) and Sequence Comparison with Other Small Pathogenic RNA Replicons Provides Evidence for Central Non-canonical Base-pairs, Large A-rich Loops, and a Terminal Branch. Journal of Molecular Biology, 262(5), 652-670. doi:10.1006/jmbi.1996.0543Giguère, T., Raj Adkar-Purushothama, C., & Perreault, J.-P. (2014). Comprehensive Secondary Structure Elucidation of Four Genera of the Family Pospiviroidae. PLoS ONE, 9(6), e98655. doi:10.1371/journal.pone.0098655López-Carrasco, A., & Flores, R. (2016). Dissecting the secondary structure of the circular RNA of a nuclear viroid in vivo: A «naked» rod-like conformation similar but not identical to that observed in vitro. RNA Biology, 14(8), 1046-1054. doi:10.1080/15476286.2016.1223005Wang, Y., Zirbel, C. L., Leontis, N. B., & Ding, B. (2018). RNA 3-dimensional structural motifs as a critical constraint of viroid RNA evolution. PLOS Pathogens, 14(2), e1006801. doi:10.1371/journal.ppat.1006801Zhong, X., Leontis, N., Qian, S., Itaya, A., Qi, Y., Boris-Lawrie, K., & Ding, B. (2006). Tertiary Structural and Functional Analyses of a Viroid RNA Motif by Isostericity Matrix and Mutagenesis Reveal Its Essential Role in Replication. Journal of Virology, 80(17), 8566-8581. doi:10.1128/jvi.00837-06Zhong, X., Tao, X., Stombaugh, J., Leontis, N., & Ding, B. (2007). Tertiary structure and function of an RNA motif required for plant vascular entry to initiate systemic trafficking. The EMBO Journal, 26(16), 3836-3846. doi:10.1038/sj.emboj.7601812Zhong, X., Archual, A. J., Amin, A. A., & Ding, B. (2008). A Genomic Map of Viroid RNA Motifs Critical for Replication and Systemic Trafficking. The Plant Cell, 20(1), 35-47. doi:10.1105/tpc.107.056606Hernandez, C., & Flores, R. (1992). Plus and minus RNAs of peach latent mosaic viroid self-cleave in vitro via hammerhead structures. Proceedings of the National Academy of Sciences, 89(9), 3711-3715. doi:10.1073/pnas.89.9.3711Fadda, Z., Daròs, J. A., Fagoaga, C., Flores, R., & Duran-Vila, N. (2003). Eggplant Latent Viroid , the Candidate Type Species for a New Genus within the Family Avsunviroidae (Hammerhead Viroids). Journal of Virology, 77(11), 6528-6532. doi:10.1128/jvi.77.11.6528-6532.2003Navarro, B., & Flores, R. (1997). Chrysanthemum chlorotic mottle viroid: Unusual structural properties of a subgroup of self-cleaving viroids with hammerhead ribozymes. Proceedings of the National Academy of Sciences, 94(21), 11262-11267. doi:10.1073/pnas.94.21.11262Bussière, F., Ouellet, J., Côté, F., Lévesque, D., & Perreault, J. P. (2000). Mapping in Solution Shows the Peach Latent Mosaic Viroid To Possess a New Pseudoknot in a Complex, Branched Secondary Structure. Journal of Virology, 74(6), 2647-2654. doi:10.1128/jvi.74.6.2647-2654.2000GAGO, S. (2005). A kissing-loop interaction in a hammerhead viroid RNA critical for its in vitro folding and in vivo viability. RNA, 11(7), 1073-1083. doi:10.1261/rna.2230605Dube, A., Baumstark, T., Bisaillon, M., & Perreault, J.-P. (2010). The RNA strands of the plus and minus polarities of peach latent mosaic viroid fold into different structures. RNA, 16(3), 463-473. doi:10.1261/rna.1826710Sogo, J. M., Koller, T., & Diener, T. O. (1973). Potato spindle tuber viroid. Virology, 55(1), 70-80. doi:10.1016/s0042-6822(73)81009-8Goodman, T. C., Nagel, L., Rappold, W., Klotz, G., & Riesner, D. (1984). Viroid replication: equilibrium association constant and comparative activity measurements for the viroid-polymerase interaction. Nucleic Acids Research, 12(15), 6231-6246. doi:10.1093/nar/12.15.6231Sanger, H. L., Klotz, G., Riesner, D., Gross, H. J., & Kleinschmidt, A. K. (1976). Viroids are single-stranded covalently closed circular RNA molecules existing as highly base-paired rod-like structures. Proceedings of the National Academy of Sciences, 73(11), 3852-3856. doi:10.1073/pnas.73.11.3852McClements, W. L., & Kaesberg, P. (1977). Size and secondary structure of potato spindle tuber viroid. Virology, 76(2), 477-484. doi:10.1016/0042-6822(77)90230-6Bustamante, C., & Keller, D. (1995). Scanning Force Microscopy in Biology. Physics Today, 48(12), 32-38. doi:10.1063/1.881478Hansma, H. G., Kasuya, K., & Oroudjev, E. (2004). Atomic force microscopy imaging and pulling of nucleic acids. Current Opinion in Structural Biology, 14(3), 380-385. doi:10.1016/j.sbi.2004.05.005Kuznetsov, Y. G., Daijogo, S., Zhou, J., Semler, B. L., & McPherson, A. (2005). Atomic Force Microscopy Analysis of Icosahedral Virus RNA. Journal of Molecular Biology, 347(1), 41-52. doi:10.1016/j.jmb.2005.01.006Alvarez, D. E., Lodeiro, M. F., Ludueña, S. J., Pietrasanta, L. I., & Gamarnik, A. V. (2005). Long-Range RNA-RNA Interactions Circularize the Dengue Virus Genome. Journal of Virology, 79(11), 6631-6643. doi:10.1128/jvi.79.11.6631-6643.200

The visual sociogram in qualitative and mixed-methods research

The paper investigates the place of visual tools in mixed-methods research on social networks, arguing that they can not only improve the communicability of results, but also support research at the data gathering and analysis stages. Three examples from the authors’ own research experience illustrate how sociograms can be integrated in multiple ways with other analytical tools, both quantitative and qualitative, positioning visualization at the intersection of varied methods and channelling substantive ideas as well as network insight in a coherent way. Visualization also facilitates the participation of a broad range of stakeholders, including among others, study participants and non-specialist researchers. It can support the capacity of qualitative and mixed-methods research to reach out to areas of the social that are difficult to circumscribe, such as hidden populations and informal organisations. On this basis, visualization appears as a unique opportunity for mixing methods in the study of social networks, emphasizing both structure and process at the same time

The acute gravitational stress of parabolic flight affects red blood cell aggregation and functionality of circulating immune cells

Postprint (published version

Pulsatile flow in coronary bifurcations for different stenting techniques

The objective of this work is to analyze the local hem odynamic changes caused in a coronary bifurcation by three different stenting techniques: simple stenting of the main vessel, simple stenting of the main vessel with kissing balloon in the side branch and culotte. To carry out this study an idealized geometry of a coronary bifurcation is used, and two bifurcation angles, 45º and 90º, are chosen as representative of the wide variety of re al configurations. In order to quantify the influence of the stenting technique on the local blood flow, both numeri- cal simulations and experimental measurements are performed. First, steady simulations are carried out with the commercial code ANSYS-Fluent, and then, experimental measurements with PIV (Particle Image Velocimetry) obtained in the laboratory are used to validate the numerical simulation. The steady computational simulations show a good overall agreement with the experimental data. Second, pulsatile flow is considered to take into account the tran- sient effects. The time averaged wall shear stress, scillatory shear index and pressure drop obtained numerically are used to compare the behavior of the stenting techniques

Incidencia del ejercicio físico y el entrenamiento vibratorio sobre la amplitud de movimiento de mujeres con fibromialgia

ResumenObjetivoEn la presente investigación hemos planteado como objetivos principales, por un lado, valorar el efecto del ejercicio físico y el entrenamiento vibratorio sobre la amplitud de movimiento en mujeres con fibromialgia (FM) y, por otro, determinar si existe alguna relación entre dicha variable y el dolor y la rigidez.MétodoLa muestra estuvo constituida por un total de cuarenta y seis mujeres (edad: 58,2±8,5 años; peso: 72,1±9,6kg; altura: 156,9±6,1cm) diagnosticadas con FM. Los participantes fueron divididos aleatoriamente en tres grupos: ejercicio físico y entrenamiento vibratorio (WBV + EJ; n=15); ejercicio físico sin vibraciones (EJ; n=15) y un grupo control (GC; n=16). Los grupos WBV + EJ y EJ realizaron dos sesiones semanales de ejercicio físico durante 8 semanas. Además, los integrantes de WBV + EJ realizaron 3 sesiones semanales de entrenamiento vibratorio (30Hz, 4mm). Las pruebas de evaluación incluyeron el test de sit and reach (variable principal), la valoración del número de tender points (TP) y una escala analógica visual (VAS) para determinar la rigidez.ResultadosLos resultados derivados del análisis intra e intergrupo no mostraron diferencias significativas en la rigidez o el número de TP, si bien, la prueba de sit and reach mostró una mejora estadísticamente significativa en WBV + EJ (58%; p<0,05). El análisis correlacional mostró una relación inversa (r =-0,55; p<0,05) entre el sit and reach y el número de TP.ConclusiónComo conclusión, podemos indicar que los datos obtenidos en la presente investigación han mostrado los efectos significativos del entrenamiento vibratorio sobre la amplitud de movimiento en mujeres con FM, aunque el número de TP o la rigidez no se vieron afectados en ningún caso.AbstractObjectiveThe main aim of this investigation was twofold: first to evaluate the effects of exercise and whole body vibration training on flexibility in women with fibromyalgia (FM) and determine whether these improvements are related to symptom severity (stiffness and bodily pain).MethodForty-six women (mean±sd, age: 58.2±8.5 years; weight: 72.1±9.6kg; height: 156.9±6.1cm) with FM were randomized into one of three groups: exercise and whole body vibration (WBV) training group (WBV + EX; n=15), exercise training group (EX), and usual-care control group (CG). WBV + EX and EX groups carried out two sessions per week of exercise training for 8 weeks. In addition, WBV + EX group performed 3 vibration-training (30Hz, 4mm) sessions per week. Outcome assessed included sit and reach test (primary outcome), tender points (TP) evaluation, and a visual analog scale (VAS) was used to determine the stiffness level.ResultsResults showed no statistical intra and intergroup differences in stiffness or the number of TP. However, a significant increment in the sit and reach performance was observed in WBV + EX (58%; p<0.05). Moreover, correlation analysis showed an inverse and significant relationship (r=-0.55; p<0.05) between sit and reach and number of TP in WBV+EX group.ConclusionIn conclusion, exercise and WBV seems to be effective on flexibility in women with FM. However, the number of TP and stiffness was not modified after the interventio