502 research outputs found
Natural and simulated aging of historical glasses
We thoroughly studied coloured glass tesserae of historical glass windows of the Santi Giovanni e Paolo Church in Venice by means of ESEM and XPS techniques in order to evaluate the weathering mechanisms of the glass surfaces. The results show a strong impoverishment of the relative content of alkaline ions on the surfaces. Moreover, we exposed the freshly broken surfaces of the samples (having the original glass composition) to an accelerated light and wet/dry aging process using the current rain composition of Venice and then compared to the natural aged surfaces. The results show the validity of the artificial aging methodology employed that allows the measurements of the different leaching rates of the samples
Corrosion Behaviour of Room Temperature Cured Polysilazane-Derived Silica Coatings on Al 5086
Silica coatings from polysilazane precursors were prepared to protect aluminium substrates from corrosion. Polysilazane can be converted to silica by simple exposition to air or basic vapours and the properties of the synthesized film make this precursor a valuable choice to obtain solid, crack-free, highly adhesive and protective coatings. The optimal deposition, obtained at 15 cm min-1 of dip-coating withdrawal speed, 20% PHPS precursor in n-butyl ether, 24 hours of exposition to 10% ammonia vapours and 6 days of ageing in air, manages to slow down the corrosion process by three orders of magnitude, therefore providing a longer lasting commodity. Specimens have been characterized by IR and XPS spectroscopy, AFM imaging and electrochemical studies
New approaches to modulate VPS34 PI 3-kinase activity
Phosphoinositide 3-kinases (PI3Ks) regulate signalling and vesicular trafficking [1-3]. Mammals have eight PI3K isoforms divided in three classes. Class I PI3Ks, frequently mutated in different pathologies [4-6], are the most studied PI3Ks and regulate signalling downstream of membrane receptors and monomeric small GTPases. In contrast, class II and III are involved in vesicular trafficking and their signalling roles have recently started to be uncovered. VPS34, the sole class III PI3K member, is found in different protein complexes that regulate autophagy, endosomal sorting, phagocytosis and signalling [7]. VPS34 functions have been studied using approaches that deplete VPS34.Those do not distinguish its scaffolding versus kinase-dependent functions, and result in VPS34-associated protein depletion, which has confounded the interpretation of the phenotypes. The aim of this study was to develop different ways of modulating VPS34 activity using two models. First, using a genetic approach, the host laboratory developed a knock-in strategy to inactivate VPS34 lipid kinase activity in mice while preserving its scaffolding function. This was a theoretical targeting approach based on VPS34 protein structure, but the resulting knock-in allele remained functionally uncharacterised. Using mammalian cells, I characterise this truncated version of VPS34 whereby exon21 is deleted and showed that is expressed and lacks lipid kinase activity. The second approach was using the nanobodies’ properties to stabilise VPS34 complexes in different conformational states to obtain VPS34 complex-specific binders, stabilizing them in active or inactive state. This is particularly relevant since pharmacological inhibition of VPS34 kinase activity disables the functions of all VPS34 complexes. Here, by overexpression in mammalian cells, I characterise nanobodies that can bind different VPS34 complexes. I focus on CI60, a VPS34 complex I-specific binder nanobody and uncover its potential as research tool to reveal unknown complex I functions and as autophagy inducer, although further experiments are required to fully address this function
Multitemporal study for the determination of changes in land use in the area of moors Tota - Bijagual - Mamapacha for the period 1992 – 2012
Debido al alto grado de intervención presentado en el complejo de páramos Tota – Bijagual –Mamapacha y en respuesta a la necesidad de desarrollar herramientas que permitan el adecuado monitoreo de esta situación, fue ejecutado el presente estudio multitemporal utilizando técnicas de Teledetección, con el objetivo de determinar las tendencias de cambio en el uso del suelo en dicha región para el periodo comprendido entre 1992 y 2012. Para esta labor fueron utilizadas imágenes Landsat 4 TM y Landsat 7 ETM tomadas en el rango temporal definido, las cuales fueron tratadas a partir diversas técnicas de procesamiento digital de imágenes, para ser posteriormente interpretadas siguiendo la metodología de clasificación de coberturas CORINE LAND COVER adaptada para Colombia. Como resultado final se obtuvieron los respectivos mapas temáticos con la identificación de las coberturas presentes en cada periodo estudiado. Adicionalmente, la información resultante del producto anterior fue analizada a nivel de pérdidas, ganancias y grado de estabilidad para cada cobertura, proceso que permitió determinar en términos de áreas y porcentajes las tendencias evolutivas del uso del suelo en la región.Due to the high level of intervention existing in the area of moors Tota – Bijagual –Mamapacha and in response of the necessity to develop tools that allow adequate monitoring of this situation, the present multitemporal study was executed using remote sensing techniques, with the aim of determine changing trends in land use in the region for the period between 1992 and 2012. For this work were used images Landsat 4 TM and Landsat 7 ETM taken at the defined temporal range, which were treated with different techniques of digital image processing, to subsequently be interpreted by following the method of coverage classification CORINE LAND COVER adapted to Colombia. As a final result, the respective thematic maps with the identification of the coverage in each period were obtained. Additionally, the resulting information of the previous product was analyzed at the level of gains, losses and level of stability for each coverage, the process allowed determination in terms of area and percentages the evolutionary tendencies of the land use in that region
As enfermeiras da Juventude Feminina da Ação Católica na Guerra Civil Espanhola e a Constituição da Salus Infirmorum
The health requirements brought about by the Spanish Civil War (1936-1939) led to the urgent organisation of health services. Nurses played a crucial role and generously took care of the civil and military populations. Objetive: we want to highlight the work carried out by nurses of the women’s branch of the Catholic Action Youth, led by their president María de Madariaga, who was appointed Deputy Inspector of women’s hospital services; and justify the creation of the Sisterhood of Nurses Salus Infirmorum. Method: It is study historical-desccriptive, based on primary and secundary sources from the archives of Catholic Action Youth and Salus Infirmorum. Results: Over 4,500 nurses of the Women's Catholic Action Youth provided care and assistance in hospitals, pharmacies, and garment workshops for combatants, visited hospitals and trained nurses. This work led to the subsequent creation of the Salus Infirmorum Sisterhood in 1942 founded by María de Madariaga as a group of Catholic nurses.Conclusion: The young women of JFAC actively participated in the national camp. Finished the war, it is created and and developed the Salus Infirmorum Sisterhood as a result leadership by María de Madariaga in the JFAC.Las necesidades sanitarias que trajo consigo la Guerra Civil española (1936-1939), provocó la urgente organización de los servicios sanitarios. Las enfermeras participaron de manera decisiva y generosa en los cuidados de la población civil y militar, en cada uno de los bandos enfrentados. Objetivo: destacar la labor de las enfermeras de la rama femenina de las jóvenes de Acción Católica (JFAC), lideradas por su presidenta María de Madariaga; y justificar la creación de la Hermandad de Enfermeras Salus Infirmorum. Metodología: estudio histórico descriptivo mediante fuentes primarias y secundarias del archivo de la Juventud Femenina de la Acción Católica y de Salus Infirmorum. Resultados: Más de 4.500 enfermeras de la JFAC prestaron atención y ayuda en hospitales, farmacias, talleres de confección de prendas para combatientes, visitando hospitales o realizando cursillos de formación para enfermeras. Esta labor derivó en la posterior creación de la Hermandad de Enfermeras Salus Infirmorum en 1942, fundada por María de Madariaga como una agrupación de enfermeras católicas. Conclusión: Las jóvenes de la JFAC participaron activamente en el bando nacional. Finalizada la guerra, se crea y desarrolla la hermandad de enfermeras Salus Infirmorum, fruto del liderazgo de María de Madariaga en la JFAC.As necessidades de saúde decorrente da Guerra Civil Espanhola (1936-1939), levaram à urgente organização dos serviços de saúde. Os enfermeiros participaram de forma decisiva e generosa no cuidado da população civil e militar, em cada um dos lados que se enfrentavam. Objetivo: destacar o trabalho das jovens enfermeiras da Ação Católica (J, lideradas por sua presidente María de Madariaga; e justificar a criação da Irmandade de Enfermeiras Salus Infirmorum. Método: Estudio histórico descritivo, com fontes primárias e secundárias, do arquivo da Juventude Feminina da Ação Católica e Salus Infirmorum. Resultados: Mais de 4.500 enfermeiras da Juventude Feminina da Ação Católica prestaram atendimento e ajuda em hospitais, farmácias, ateliê de roupas para combatentes, visitando hospitales ou realizando cursos de formação para enfermeiras. Este trabalho levou à criação posterior da Irmandade de Enfermeiras Salus Infirmorum em 1942, fundada por María de Madariaga como um grupo de enfermeiras católicas. Conclusões: As jovens do JFAC participaram ativamente do acampamento nacional. Após a guerra, a irmandade de enfermeiras Salus Infirmorum foi criada e desenvolvida, como resultado da liderança de María de Madariaga no JFAC
Exploring emotional responses on Twitter after the Algeciras attack on Catholic churches in 2023: Between anti-immigration discourse and sadness reactions
[EN] On 25 February, a Muslim man attacked several churches in Algeciras (Spain) and killed a sexton. After the attack, many people turned to social media, especially Twitter, to express their emotions about what had happened, send their condolences to the deceased’s family, or criticize the government, as the perpetrator was allegedly an undocumented migrant with a pending deportation order. The aim of this work is to study the emotional reactions of Twitter users who participated in conversations about the Algeciras case by applying sentiment analysis techniques. Using the academictwitteR package, more than 300,000 tweets containing the word 'Algeciras' were obtained. We then filtered out the RTs and kept 36,104 original tweets for this work. After data cleaning and tokenization, sentiment analysis was applied using the syuzhet package in R, which allowed to obtain the intensity of positive or negative sentiments and eight different emotions. The results suggest a higher prevalence of negative sentiments related to conversations about attacks, murder, or grief. The use of negative words reflects Twitter users’ emotions, which are mainly concentrated on fear, anger, and sadness. Tweets expressing these emotions also indicated signs of Islamophobia and racism towards the murderer and, by extension, other Muslim immigrants.Grant PID2021-123983OB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”. Margarita Salas Grant funded by European Union nextGeneration-EU. ESEIS (SEJ-216)/COIDESO Centers and EPIT2023 from University of HuelvaRebollo-Díaz, C.; Gualda, E.; Ruiz-Ángel, E. (2023). Exploring emotional responses on Twitter after the Algeciras attack on Catholic churches in 2023: Between anti-immigration discourse and sadness reactions. Editorial Universitat Politècnica de València. 149-150. http://hdl.handle.net/10251/20179514915
Sexualidad y tercera edad
La sociedad del siglo XXI, se identifica por un conjunto de características, entre las que podríamos destacar el aumento de la esperanza de vida o los avances tecnológicos y científicos. Estos rasgos, han generado un envejecimiento social del que no nos podemos olvidar a la hora de crear planes, proyectos y programas cuyo objetivo sea, la mejora de la calidad de vida de las personas mayores.
El objetivo de este trabajo es, estudiar la situación actual de las personas mayores, concediendo mayor atención a la relación entre la calidad de vida y la sexualidad para plantear, posteriormente, una propuesta de intervención. Con esta propuesta se pretende ampliar el conocimiento, de las personas mayores, en relación a la sexualidad y así desmontar falsas creencias sobre este tema.
El siguiente trabajo se estructura en varias partes diferenciadas, con una relación entre ellas para dar coherencia al trabajo. Planteamos, conceptos fundamentales sobre sexualidad y tercera edad, tercera edad en el siglo XXI, sexualidad y tercera edad y finalmente se presenta una propuesta de intervención para generar, en las personas mayores, un conocimiento más real de su vida sexual y amorosa desde una actitud positiva y gratificante eliminando prejuicios y estereotipos.Grado en Educación Socia
Strategies for cooperation emergence in distributed service discovery
This is an Accepted Manuscript of an article published by Taylor & Francis in Cybernetics and Systems on APR 3 2014], available online:http://www.tandfonline.com/10.1080/01969722.2014.894848[EN] In distributed environments where entities only have a partial view of the system, cooperation plays a key issue. In the case of decentralized service discovery in open agent societies, agents only know about the services they provide and who are their direct neighbors. Therefore, they need the cooperation of their neighbors in order to locate the required services. However, cooperation is
not always present in open systems. Non-cooperative agents pursuing their own goals could refuse to forward queries from other agents to avoid the cost of this action; therefore, the efficiency of the decentralized service discovery could be seriously damaged. In this paper, we propose the ombination of incentives and local structural changes in order to promote cooperation in the service discovery
process. The results show that, even in scenarios where the predominant behavior is not collaborative cooperation emerges.The work was partially supported by the Spanish Ministry of Science and Innovation through grants TIN2009-13839-C03-01, TIN2012-36586-C03-01, CSD2007-0022 (CONSOLIDER-INGENIO 2010).Del Val Noguera, E.; Rebollo Pedruelo, M.; Botti, V. (2014). Strategies for cooperation emergence in distributed service discovery. Cybernetics and Systems. 45(3):220-240. https://doi.org/10.1080/01969722.2014.894848S220240453Blanc , A. , Y.K. Liu , and A. Vahdat . “Designing Incentives for Peer-to-Peer Routing.” InProceedings of the 24th Annual Joint Conference of the IEEE Computer and Communications Societies, Vol. 1, pp. 374–385, 2005 .del Val , E. “Semantic Service Management in Service-Oriented Multi-Agent Systems.” Ph.D. thesis, Departament de Sistemes Informàtics i Computació, Universitat Politècnica de València, 2013 .Del Val, E., Rebollo, M., & Botti, V. (2012). Enhancing decentralized service discovery in open service-oriented multi-agent systems. Autonomous Agents and Multi-Agent Systems, 28(1), 1-30. doi:10.1007/s10458-012-9210-0DORAN, J. E., FRANKLIN, S., JENNINGS, N. R., & NORMAN, T. J. (1997). On cooperation in multi-agent systems. The Knowledge Engineering Review, 12(3), 309-314. doi:10.1017/s0269888997003111Eguíluz, V. M., Zimmermann, M. G., Cela‐Conde, C. J., & Miguel, M. S. (2005). Cooperation and the Emergence of Role Differentiation in the Dynamics of Social Networks. American Journal of Sociology, 110(4), 977-1008. doi:10.1086/428716Griffiths , N. and M. Luck . “Changing Neighbours: Improving Tag-Based Cooperation.” InProceedings of the 9th International Conference on Autonomous Agents and Multiagent Systems: volume 1.(AAMAS'10), 249–256. Richland, SC: International Foundation for Autonomous Agents and Multiagent Systems, 2010 .Gu , B. and S. Jarvenpaa . “Are Contributions to p2p Technical Forums Private or Public Goods? An Empirical Investigation.” Paper presented at the 1st Workshop on Economics of Peer-to-Peer Systems, June 4–5, 2004, Harvard University .Hauert, C., Traulsen, A., Brandt, H., Nowak, M. A., & Sigmund, K. (2007). Via Freedom to Coercion: The Emergence of Costly Punishment. Science, 316(5833), 1905-1907. doi:10.1126/science.1141588Hofmann , L.M. , N. Chakraborty , and K. Sycara . “The Evolution of Cooperation in Self-Interested Agent Societies: A Critical Study.” InProceedings of the 10th International Conference on Autonomous Agents and Multiagent Systems, Volume 2 , edited by K. Tumer , P. Yolum , L. Sonenberg , and P. Stone , 685–692. IFAAMAS, 2011 .Lin, W. S., Zhao, H. V., & Liu, K. J. R. (2009). Incentive Cooperation Strategies for Peer-to-Peer Live Multimedia Streaming Social Networks. IEEE Transactions on Multimedia, 11(3), 396-412. doi:10.1109/tmm.2009.2012915Nowak, M. A. (2006). Five Rules for the Evolution of Cooperation. Science, 314(5805), 1560-1563. doi:10.1126/science.1133755Nowak, M. A., & Sigmund, K. (1998). Evolution of indirect reciprocity by image scoring. Nature, 393(6685), 573-577. doi:10.1038/31225Ohtsuki, H., Hauert, C., Lieberman, E., & Nowak, M. A. (2006). A simple rule for the evolution of cooperation on graphs and social networks. Nature, 441(7092), 502-505. doi:10.1038/nature04605Santos, F. C., Santos, M. D., & Pacheco, J. M. (2008). Social diversity promotes the emergence of cooperation in public goods games. Nature, 454(7201), 213-216. doi:10.1038/nature06940Shneidman , J. and D. C. Parkes . “Rationality and Self-Interest in Peer to Peer Networks.” Paper presented at the 2nd Int. Workshop on Peer-to-Peer Systems (IPTPS’03), February 20–21, 2003, Berkeley, CA .Sigmund, K. (2007). Punish or perish? Retaliation and collaboration among humans. Trends in Ecology & Evolution, 22(11), 593-600. doi:10.1016/j.tree.2007.06.012Sigmund, K. (2009). Sympathy and similarity: The evolutionary dynamics of cooperation. Proceedings of the National Academy of Sciences, 106(21), 8405-8406. doi:10.1073/pnas.0903947106Sigmund, K., Hauert, C., & Nowak, M. A. (2001). Reward and punishment. Proceedings of the National Academy of Sciences, 98(19), 10757-10762. doi:10.1073/pnas.161155698Sun , Q. and H. Garcia-Molina . “Slic: A Selfish Link-Based Incentive Mechanism for Unstructured Peer-To-Peer Networks.” Paper presented at the 24th International Conference on Distributed Computing Systems (ICDCS’04), March 23–26, 2004, Washington, DC .Villatoro , D. , J. Sabater-Mir , and S. Sen . “Social Instruments for Robust Convention Emergence.”Proceedings of the International Joint Conference on Artificial Intelligence, edited by T. Walsh, 420–425, 2011
Analyzing urban mobility paths based on users' activity in social networks
[EN] This work presents an approach to model how the activity in social media of the citizens reflects the activity in the city. The proposal includes a gravitational model that deforms the surface of the city based on the intensity of the activity in different zones. The information is extracted from geolocated tweets (n = 1.48 x 10(6)). Furthermore, this activity affects how people move in a city. The path a user follows is calculated using the geolocation of the tweets that he or she publishes along the day. Several models are evaluated and compared using the Hausdorfs distance (d(H)). The combination of gravitational potential with attraction to the destination points provides the best results, with d(H) = 1176 against the Manhattan (d(H) = 1203) or the geodesic (d(H) = 1417) alternatives. Finally, the analysis is repeated with the data segmented by gender (n=2,826 paths, men=1,910, women=916). The results validate (p=0.000334) the studies that affirm that men travel longer distances (d(M) = 4.73 km, alpha(m) = 26.1 degrees) with rectilinear trajectories, whereas women have shorter and more angled paths (d(w) = 4.5 km, alpha(w) = 32.2 degrees), obtaining p values in path lengths and p=0.006 in the angles. (C) 2019 Elsevier B.V. All rights reserved.This work is partially supported by Spanish Government Project TIN2015-65515-C4-1-R and the Post-doc grant Ref. SP20170057.Rodríguez, L.; Palanca Cámara, J.; Del Val Noguera, E.; Rebollo Pedruelo, M. (2020). Analyzing urban mobility paths based on users' activity in social networks. Future Generation Computer Systems. 102:333-346. https://doi.org/10.1016/j.future.2019.07.072S33334610
Hierarchical categorisation of tags for delicious
In the scenario of social bookmarking, a user browsing the Web bookmarks web pages and assigns free-text labels (i.e., tags) to them according to their personal preferences.
In this technical report, we approach one of the practical aspects when it comes to represent users' interests from their tagging activity, namely the categorization of tags into high-level categories of interest. The reason is that the representation of user profiles on the basis of the myriad of tags available on the Web is certainly unfeasible from various practical perspectives; mainly concerning the unavailability of data to reliably, accurately measure interests across such fine-grained categorisation, and, should the data be available, its overwhelming computational intractability. Motivated by this, our study presents the results of a categorization process whereby a collection of tags posted at Delicious #http://delicious.com# are classified into 200 subcategories of interest.Preprin
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