Towards and inclusive definition of e-learning

L'estudi té com a objectiu la construcció d'una definició actual i integradora del concepte d'e-learning, que sigui acceptada per la major part de la comunitat científica i que serveixi com a referent pels estudiosos i professionals d'aquesta temàtica.El estudio tiene como objetivo la construcción de una definición actual e integradora del concepto de e-learning, que sea aceptada por la mayor parte de la comunidad científica y que sirva como referente para los estudiosos y profesionales de esta temática.The main aim of the project is to create an up-to-date and comprehensive definition of the concept of e-learning. The project aimed to ensure that the definition was accepted by the scientific community and became a point of reference for experts and professionals in the field

Dynamic capabilities and innovation: a Multiple-Case Study

After a detailed survey of the scientific literature, it was found that several characteristics of dynamic capabilities were similar to those of innovation capability. Therefore, with a deeper study of the first ones, it could be possible to design a model aimed to structure innovation capability. Thus, this work presents a conceptual model, where the innovation capability is shown as result of three processes: knowledge absorption and creation capability, knowledge integration and knowledge reconfiguration. Furthermore, taking into account that dynamic capabilities are underpinned on actors, physical resources, structures and systems, and organizational culture, the model uses variables that integrate each one of these four subconstructos in order to facilitate the measurement of innovation capability in future researches. Moreover, the model separates knowledge exploitation and exploration activities. Applying this model, firms will be able of structuring and identifying the more important activities in the process of continuous innovation. Finally, model validation is done by means of an exploratory multiple-case study, which is applied on three technology-based companies of the audiovisual sector

Good practices of innovation: an exploratory case study in the broadcasting sector

The main objective of this research is to contribute to innovation capability understanding. Furthermore, it is mainly focused in the way innovation capability is built and developed. Based on a multiple case study and interviews with managers, who are responsible for the new product development projects, in two innovative technology- based companies (ITBC) in the broadcasting sector, a collection of practices are identified and classified in four dimensions: 1) Innovation strategy, 2) Human capital development, 3) Organizational structure, and 4) Organizational culture. The case analysis revealed that a collection of practices that promote successful results in the new product development projects are critical both to improve and to build innovation capabilityPostprint (published version

Good practices to develop innovation capability: two case studies in the broadcasting sector

The main objective of this research is to contribute to innovation capability understanding. Furthermore, it is mainly focused in the way innovation capability is built and developed. Based on a multiple case study and interviews with managers, who are responsible for the new product development projects, in two innovative technology- based companies (ITBC) in the broadcasting sector, a collection of practices are identified and classified in four dimensions: 1) Innovation strategy, 2) Human capital development, 3) Organizational structure, and 4) Organizational culture. The case analysis revealed that a collection of practices that promote successful results in the new product development projects are critical both to improve and to build innovation capabilityPeer ReviewedPreprintPresentat al XX Congreso Nacional ACEDE,Granada, 201

Multiparallel Three-Dimensional Optical Microscopy

Multiparallel three-dimensional optical microscopy is a method of forming an approximate three-dimensional image of a microscope sample as a collection of images from different depths through the sample. The imaging apparatus includes a single microscope plus an assembly of beam splitters and mirrors that divide the output of the microscope into multiple channels. An imaging array of photodetectors in each channel is located at a different distance along the optical path from the microscope, corresponding to a focal plane at a different depth within the sample. The optical path leading to each photodetector array also includes lenses to compensate for the variation of magnification with distance so that the images ultimately formed on all the photodetector arrays are of the same magnification. The use of optical components common to multiple channels in a simple geometry makes it possible to obtain high light-transmission efficiency with an optically and mechanically simple assembly. In addition, because images can be read out simultaneously from all the photodetector arrays, the apparatus can support three-dimensional imaging at a high scanning rate

Nanomechanics of tip-link cadherins

Hearing and balance rely on the transduction of mechanical stimuli arising from sound waves or head movements into electrochemical signals. This archetypal mechanoelectrical transduction process occurs in the hair-cell stereocilia of the inner ear, which experience continuous oscillations driven by undulations in the endolymph in which they are immersed. The filamentous structures called tip links, formed by an intertwined thread composed of an heterotypic complex of cadherin 23 and protocadherin 15 ectodomain dimers, connect each stereocilium to the tip of the lower sterocilium, and must maintain their integrity against continuous stimulatory deflections. By using single molecule force spectroscopy, here we demonstrate that in contrast to the case of classical cadherins, tip-link cadherins are mechanoresilient structures even at the exceptionally low Ca2+ concentration of the endolymph. We also show that the D101G deafness point mutation in cadherin 23, which affects a Ca2+ coordination site, exhibits an altered mechanical phenotype at the physiological Ca2+ concentration. Our results show a remarkable case of functional adaptation of a protein’s nanomechanics to extremely low Ca2+ concentrations and pave the way to a full understanding of the mechanotransduction mechanism mediated by auditory cadherinsThis work was supported by the BIO2010-22275 grant from the Spanish Ministry of Science and Innovation (MICINN) to M.C.-V

総説

Background National estimates on per capita alcohol consumption are provided regularly by various sources and may have validity problems, so corrections are needed for monitoring and assessment purposes. Our objectives were to compare different alcohol availability estimates for Spain, to build the best estimate (actual consumption), characterize its time trend during 2001–2011, and quantify the extent to which other estimates (coverage) approximated actual consumption. Methods Estimates were: alcohol availability from the Spanish Tax Agency (Tax Agency availability), World Health Organization (WHO availability) and other international agencies, self-reported purchases from the Spanish Food Consumption Panel, and self-reported consumption from population surveys. Analyses included calculating: between-agency discrepancy in availability, multisource availability (correcting Tax Agency availability by underestimation of wine and cider), actual consumption (adjusting multisource availability by unrecorded alcohol consumption/purchases and alcohol losses), and coverage of selected estimates. Sensitivity analyses were undertaken. Time trends were characterized by joinpoint regression. Results Between-agency discrepancy in alcohol availability remained high in 2011, mainly because of wine and spirits, although some decrease was observed during the study period. The actual consumption was 9.5 l of pure alcohol/person-year in 2011, decreasing 2.3 % annually, mainly due to wine and spirits. 2011 coverage of WHO availability, Tax Agency availability, self-reported purchases, and self-reported consumption was 99.5, 99.5, 66.3, and 28.0 %, respectively, generally with downward trends (last three estimates, especially self-reported consumption). The multisource availability overestimated actual consumption by 12.3 %, mainly due to tourism imbalance. Conclusions Spanish estimates of per capita alcohol consumption show considerable weaknesses. Using uncorrected estimates, especially self-reported consumption, for monitoring or other purposes is misleading. To obtain conservative estimates of alcohol-attributable disease burden or heavy drinking prevalence, self-reported consumption should be shifted upwards by more than 85 % (91 % in 2011) of Tax Agency or WHO availability figures. The weaknesses identified can probably also be found worldwide, thus much empirical work remains to be done to improve estimates of per capita alcohol consumption.The authors are grateful to Kathy Fitch for translation. This work was supported by Spanish Health Research and Development Strategy (PI13/00183; PI15CIII/00022), National Plan on Drugs (2015I040). Writing of the paper was also partially supported by a grant of the National Plan on Drugs (Res. 8-7-15. Secretaría de Estado de Servicios Sociales e Igualdad) to the Alcohol Work Group of the Spanish Society of Epidemiology.S

Ethylene is Involved in Symptom Development and Ribosomal Stress of Tomato Plants upon Citrus Exocortis Viroid Infection

[EN] Citrus exocortis viroid (CEVd) is known to cause different symptoms in citrus trees, and its mechanism of infection has been studied in tomato as an experimental host, producing ribosomal stress on these plants. Some of the symptoms caused by CEVd in tomato plants resemble those produced by the phytohormone ethylene. The present study is focused on elucidating the relationship between CEVd infection and ethylene on disease development. To this purpose, the ethylene insensitive Never ripe (Nr) tomato mutants were infected with CEVd, and several aspects such as susceptibility to infection, defensive response, ethylene biosynthesis and ribosomal stress were studied. Phenotypic characterization revealed higher susceptibility to CEVd in these mutants, which correlated with higher expression levels of both defense and ethylene biosynthesis genes, as well as the ribosomal stress marker SlNAC082. In addition, Northern blotting revealed compromised ribosome biogenesis in all CEVd infected plants, particularly in Nr mutants. Our results indicate a higher ethylene biosynthesis in Nr mutants and suggest an important role of this phytohormone in disease development and ribosomal stress caused by viroid infection.Vázquez Prol, F.; López-Gresa, MP.; Rodrigo Bravo, I.; Belles Albert, JM.; Lisón, P. (2020). Ethylene is Involved in Symptom Development and Ribosomal Stress of Tomato Plants upon Citrus Exocortis Viroid Infection. Plants. 9(5):1-15. https://doi.org/10.3390/plants9050582S11595Flores, 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.43.040204.140243Adkar‐Purushothama, C. R., & Perreault, J. (2019). Current overview on viroid–host interactions. WIREs RNA, 11(2). doi:10.1002/wrna.1570Di Serio, F., Flores, R., Verhoeven, J. T. J., Li, S.-F., Pallás, V., Randles, J. W., … Owens, R. A. (2014). Current status of viroid taxonomy. Archives of Virology, 159(12), 3467-3478. doi:10.1007/s00705-014-2200-6Verhoeven, J. th. j., Jansen, C. C. C., Willemen, T. M., Kox, L. F. F., Owens, R. A., & Roenhorst, J. W. (2004). Natural infections of tomato by Citrus exocortis viroid, Columnea latent viroid, Potato spindle tuber viroid and Tomato chlorotic dwarf viroid. European Journal of Plant Pathology, 110(8), 823-831. doi:10.1007/s10658-004-2493-5López-Gresa, M. P., Lisón, P., Yenush, L., Conejero, V., Rodrigo, I., & Bellés, J. M. (2016). Salicylic Acid Is Involved in the Basal Resistance of Tomato Plants to Citrus Exocortis Viroid and Tomato Spotted Wilt Virus. PLOS ONE, 11(11), e0166938. doi:10.1371/journal.pone.0166938Wang, Y., Wu, J., Qiu, Y., Atta, S., Zhou, C., & Cao, M. (2019). Global Transcriptomic Analysis Reveals Insights into the Response of ‘Etrog’ Citron (Citrus medica L.) to Citrus Exocortis Viroid Infection. Viruses, 11(5), 453. doi:10.3390/v11050453Jia, C., Zhang, L., Liu, L., Wang, J., Li, C., & Wang, Q. (2013). Multiple phytohormone signalling pathways modulate susceptibility of tomato plants to Alternaria alternata f. sp. lycopersici. Journal of Experimental Botany, 64(2), 637-650. doi:10.1093/jxb/ers360Van Loon, L. C., Geraats, B. P. J., & Linthorst, H. J. M. (2006). Ethylene as a modulator of disease resistance in plants. Trends in Plant Science, 11(4), 184-191. doi:10.1016/j.tplants.2006.02.005Bellés, J. M., & Conejero, V. (1989). Ethylene Mediation of the Viroid-Like Syndrome Induced by Ag+Ions inGynura aurantiacaDC Plants. Journal of Phytopathology, 124(4), 275-284. doi:10.1111/j.1439-0434.1989.tb04924.xDubois, M., Van den Broeck, L., & Inzé, D. (2018). The Pivotal Role of Ethylene in Plant Growth. Trends in Plant Science, 23(4), 311-323. doi:10.1016/j.tplants.2018.01.003Yang, S. F., & Hoffman, N. E. (1984). Ethylene Biosynthesis and its Regulation in Higher Plants. 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Proceedings of the National Academy of Sciences, 109(47), 19486-19491. doi:10.1073/pnas.1214848109Aloni, R., Wolf, A., Feigenbaum, P., Avni, A., & Klee, H. J. (1998). The Never ripe Mutant Provides Evidence That Tumor-Induced Ethylene Controls the Morphogenesis ofAgrobacterium tumefaciens-Induced Crown Galls on Tomato Stems1,2. Plant Physiology, 117(3), 841-849. doi:10.1104/pp.117.3.841Klee, H. J. (2004). Ethylene Signal Transduction. Moving beyond Arabidopsis. Plant Physiology, 135(2), 660-667. doi:10.1104/pp.104.040998Chen, Y., Rofidal, V., Hem, S., Gil, J., Nosarzewska, J., Berger, N., … Chervin, C. (2019). Targeted Proteomics Allows Quantification of Ethylene Receptors and Reveals SlETR3 Accumulation in Never-Ripe Tomatoes. Frontiers in Plant Science, 10. doi:10.3389/fpls.2019.01054HU, X., NIE, X., SONG, Y., XIONG, X., & Tai, H. (2011). Ethylene is Involved but Plays a Limited Role in Tomato Chlorotic Dwarf Viroid-Induced Symptom Development in Tomato. Agricultural Sciences in China, 10(4), 544-552. doi:10.1016/s1671-2927(11)60035-7Dı́az, J., ten Have, A., & van Kan, J. A. L. (2002). The Role of Ethylene and Wound Signaling in Resistance of Tomato to Botrytis cinerea  . Plant Physiology, 129(3), 1341-1351. doi:10.1104/pp.001453Lund, S. T., Stall, R. E., & Klee, H. J. (1998). Ethylene Regulates the Susceptible Response to Pathogen Infection in Tomato. The Plant Cell, 10(3), 371-382. doi:10.1105/tpc.10.3.371Tsolakidou, M.-D., Pantelides, lakovos S., Tzima, A. K., Kang, S., Paplomatas, E. J., & Tsaltas, D. (2019). Disruption and Overexpression of the Gene Encoding ACC (1-Aminocyclopropane-1-Carboxylic Acid) Deaminase in Soil-Borne Fungal Pathogen Verticillium dahliae Revealed the Role of ACC as a Potential Regulator of Virulence and Plant Defense. Molecular Plant-Microbe Interactions®, 32(6), 639-653. doi:10.1094/mpmi-07-18-0203-rWięsyk, A., Iwanicka-Nowicka, R., Fogtman, A., Zagórski-Ostoja, W., & Góra-Sochacka, A. (2018). Time-Course Microarray Analysis Reveals Differences between Transcriptional Changes in Tomato Leaves Triggered by Mild and Severe Variants of Potato Spindle Tuber Viroid. Viruses, 10(5), 257. doi:10.3390/v10050257Eiras, M., Nohales, M. A., Kitajima, E. W., Flores, R., & Daròs, J. A. (2010). Ribosomal protein L5 and transcription factor IIIA from Arabidopsis thaliana bind in vitro specifically Potato spindle tuber viroid RNA. Archives of Virology, 156(3), 529-533. doi:10.1007/s00705-010-0867-xDubé, A., Bisaillon, M., & Perreault, J.-P. (2009). Identification of Proteins from Prunus persica That Interact with Peach Latent Mosaic Viroid. Journal of Virology, 83(23), 12057-12067. doi:10.1128/jvi.01151-09Lisón, P., Tárraga, S., López-Gresa, P., Saurí, A., Torres, C., Campos, L., … Rodrigo, I. (2013). A noncoding plant pathogen provokes both transcriptional and posttranscriptional alterations in tomato. 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Salicylic Acid Is Involved in the Basal Resistance of Tomato Plants to Citrus Exocortis Viroid and Tomato Spotted Wilt Virus

[EN] Tomato plants expressing the NahG transgene, which prevents accumulation of endogenous salicylic acid (SA), were used to study the importance of the SA signalling pathway in basal defence against Citrus Exocortis Viroid (CEVd) or Tomato Spotted Wilt Virus (TSWV). The lack of SA accumulation in the CEVd- or TSWV-infected NahG tomato plants led to an early and dramatic disease phenotype, as compared to that observed in the corresponding parental Money Maker. Addition of acibenzolar-S-methyl, a benzothiadiazole (BTH), which activates the systemic acquired resistance pathway downstream of SA signalling, improves resistance of NahG tomato plants to CEVd and TSWV. CEVd and TSWV inoculation induced the accumulation of the hydroxycinnamic amides p-coumaroyltyramine, feruloyltyramine, caffeoylputrescine, and feruloylputrescine, and the defence related proteins PR1 and P23 in NahG plants earlier and with more intensity than in Money Maker plants, indicating that SA is not essential for the induction of these plant defence metabolites and proteins. In addition, NahG plants produced very high levels of ethylene upon CEVd or TSWV infection when compared with infected Money Maker plants, indicating that the absence of SA produced additional effects on other metabolic pathways. This is the first report to show that SA is an important component of basal resistance of tomato plants to both CEVd and TSWV, indicating that SA-dependent defence mechanisms play a key role in limiting the severity of symptoms in CEVd- and TSWV-infected NahG tomato plants.This work was supported by grant BIO2012-33419 from the Spanish Ministry of Economy and Competitiveness received by JMB. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.López-Gresa, MP.; Lisón, P.; Yenush, L.; Conejero Tomás, V.; Rodrigo Bravo, I.; Belles Albert, JM. (2016). Salicylic Acid Is Involved in the Basal Resistance of Tomato Plants to Citrus Exocortis Viroid and Tomato Spotted Wilt Virus. PLoS ONE. 11(11). https://doi.org/10.1371/journal.pone.0166938S111