Status of research on collaboration in Virtual Learning Environments

El aprendizaje colaborativo posee una tradición teórica y práctica amplia en la educación general, como en la educación superior. No obstante, la actividad de coordinación entre personas que buscan aprender no es sencilla de gestionar. Esta complejidad aumenta cuando entre la actividad colaborativa surge un nuevo componente, la tecnología. ¿Qué se ha avanzado sobre el aprendizaje colaborativo mediado tecnológicamente? Este trabajo tiene como objetivo analizar el estado de la investigación sobre aprendizaje colaborativo en Educación Superior en los Entornos Virtuales de Aprendizaje (EVA). Para ello se realiza un análisis bibliométrico de las publicaciones indexadas de la base de datos SCOPUS. El análisis de redes bibliométricas reveló que la producción científica sobre el aprendizaje colaborativo en educación superior es creciente pero no homogéneo en el tiempo, que las Ciencias Sociales y Ciencias de la Computación son las que más producen, hay un especial énfasis en entender la colaboración en entornos b-learning y que se pueden reconocer dos tendencias clave en el desarrollo: 1) la aceptación de la mediación colaborativa virtual en los procesos de educación superior y 2) la necesidad de implementar matices metodológicos colaborativas (portafolio y otras alternati-vas pedagógicas) y ensayar otras herramientas virtuales (redes sociales)Collaborative learning has a broad theoretical and practical tradition in general education, as in higher education. However, coordination of people who seek to learn is not an easy task to manage. This complexity increases when technology arises as component of collaboration. What are the advances on technology-assisted collaborative learning? This work aims to analyze the state of the research on collaborative learning in Higher Education in Virtual Learning Environments (EVA). To achieve this purpose, a bibliometric analysis of the indexed publications of the SCOPUS database is carried out. Network bibliometric analyses revealed that the scientific production on collaborative learning in higher education is grow-ing but not homogeneous over time. Most active disciplines proved to be Social Sciences and Computer Scienc-es, and a special emphasis on understanding the Collaboration in b-learning environments showed two developing trends: 1) the acceptance of virtual collaborative media-tion in higher education processes and 2) the need to implement collaborative methodological nuances (portfolio and other pedagogical alternatives) and trying out other virtual tools (social networks)

El mandato de los líder y la obediencia de los colaboradores. La importancia del liderazgo compartido

La literatura recoge abundante investigación, libros, artículos, etc. sobre estilos de dirección y liderazgo. En las aulas enseñamos a dirigir a otros y explicamos las características de los líderes. Sin embargo, hay poca reflexión sobre el papel de los que reciben las órdenes, sobre la importancia de obedecer correctamente y de saber “gestionar a los jefes”. De ahí, que el documento que se presenta recoja las dos partes de liderazgo, la de los líderes, pero también la de los colaboradores, porque no hay buen liderazgo sin la correcta implicación de los dirigidos. El documento recoge primero los atributos esenciales de los líderes y se detiene después en la parte de los colaboradores o empleados. Posteriormente se describe el experimentado llevado a cabo por Milgram que puede ayudar a que ambos, líderes y colaboradores, reflexionen sobre cómo dirigir y cómo obedecer. A continuación, se introduce un resumen de las dimensiones que todos los líderes deberían tener desarrolladas. El documento finaliza con un breve epígrafe dedicado al liderazgo compartido y con la conclusión de que en el fondo “todos somos líderes”.Suárez Ruz, ME.; Conesa García, MP. (2022). El mandato de los líder y la obediencia de los colaboradores. La importancia del liderazgo compartido. http://hdl.handle.net/10251/18341

El refuerzo tutorial mediante pruebas objetivas en materias de contenidos científico y técnico

Los autores de este artículo pretenden ordenar los factores que deben tenerse en cuenta, en base a su experiencia en materias científicas y técnicas, a la hora de diseñar un cuestionario de respuestas alternativas enfocando al refuerzo tutorial más que a la propia evaluación los numerosos parámetros que en este caso intervienen; aconsejando usar un soporte informático bien estructurado. En este trabajo se propone una estructura de este tipo como orientación.The authors of this work try to put in order the factors that they experience in scientific and technical subjects has revealed to design tests not only to do evaluations but also to give the students tutorial reinforcements. There are many parameters involved in this kind of test. This is the reason which advises to use well-structured computer systems. In this work is proposed a structure like orientative example.peerReviewe

Actividades antimicrobianas derivadas de fagos y su aplicación como bioconservantes alimentarios

Comunicación presentada en el XXII Congreso Nacional SEM 2009, celebrado en Almeria del 21 al 24 de septiembre de 2009.Staphylococcus aureus es un importante patógeno asociados a intoxicaciones de tipo alimentario, y a su vez, uno de los principales agentes causantes de la mastitis en el ganado vacuno.Peer reviewe

Synergy between the phage endolysin LysH5 and nisin to kill Staphylococcus aureus in pasteurized milk

Phage-encoded endolysins are recently considered as new biocontrol tools to inhibit pathogens in food. In this work, we have studied the ionic requirements for optimal lytic activity of LysH5, the endolysin encoded by the staphylococcal bacteriophage phi-SauS-IPLA88. LysH5 activity was inhibited by the presence of Mn++ and Zn++ and enhanced by Ca++, Mg++ and NaCl. When LysH5 was combined with nisin, a bacteriocin currently used as a biopreservative in food, a strong synergistic effect was observed. The Minimum Inhibitory Concentrations of nisin and LysH5 were reduced 64- and 16-fold, respectively, as determined in checkerboard microtitre tests. In addition, nisin enhanced 8-fold the lytic activity of LysH5 on cell suspensions. The synergy observed in vitro was confirmed in challenge assays in pasteurized milk contaminated with S. aureus Sa9. Clearance of the pathogen was only achieved by the combined activity of both antimicrobials. As far as we know, this is the first study that exploits the possibilities of hurdle technology combining a phage-encoded endolysin and the bacteriocin nisin for efficient S. aureus inhibition in milk.This research study was supported by grant AGL2009-13144-C02-01 from the Ministry of Science and Innovation of Spain and IB08-052 from FICYT (Regional Government of Asturias).Peer reviewe

Posibilidades de implantación de una plataforma virtual para la mejora de la comercialización de los cítricos en Andalucía. Necesidades de información de los productores y exportadores

Andalucía es la segunda región productora de cítricos de España, teniendo por tanto una extraordinaria importancia económica y social. Sin embargo, la cadena de valor de los cítricos comprende un sector productor bastante atomizado frente a unos compradores muy concentrados y organizados, y un mercado poco transparente. El objetivo de esta investigación fue determinar las necesidades de información de los principales agentes implicados en la cadena de valor de los cítricos y estudiar las posibilidades que tendría la implantación de una plataforma virtual para mejorar las decisiones empresariales en la comercialización de los productos. Para ello, se emplearon fuentes primarias, centradas en la realización de entrevistas a expertos de la producción de cítricos en Andalucía, segmentando el análisis sobre la base de la naturaleza jurídica y la actividad de los entrevistados. Esta acción estratégica puede ser viable puesto que hay una clara demanda de información por parte de la población encuestada, que representa el 65% de la producción citrícola andaluza. Además, se constató que el modelo de gestión debería ser mixto, públicoprivada. La responsabilidad de la misma debería ser privada, ya que en general se percibió cierta reticencia en la Administración. La mayoría de los encuestados estarían dispuestos a pagar por los servicios que suministre la plataforma, si bien señalaron restricciones en cuanto al acceso, calidad del servicio y precioAndalusia is the second largest citrus producer in Spain, and thus, the citrus industry has an extraordinary economic and social importance in the region. However, the citrus value chain comprises a scattered primary sector in contrast to a very concentrated and well organized purchase and distribution sector, as well as a non-transparent market. The aim of this research was to explore the information needs of the different agents in the citrus value chain and to study the possibilities of implementing a opavirtual platform to share information in order to improve their marketing decisions. Primary sources were used for this work: a survey was conducted among citrus production experts in Andalusia. Survey results were analysed according to the legal nature and the activity of the respondents. The strategic action of implementing an information platform may be feasible since a clear demand for information has been detected from the survey population which represents 65% of the Andalusia citrus production. In addition, a public-private management model was preferred by the respondents to control the platform although the responsibility for it should be private. The majority of respondents would be willing to pay for the services provided by the platform, although some aspects regarding access restrictions service quality and price should be consideredFundación Corporación Tecnológica de Andalucía (CTA) 1480/056

Heparan sulfate proteoglycans undergo differential expression alterations in left sided colorectal cancer, depending on their metastatic character

Abstract Background Heparan sulfate proteoglycans (HSPGs) are complex molecules which play a role in the invasion and growth and metastatic properties of cancerous cells. In this work we analyze changes in the patterns of expression of HSPGs in left sided colorectal cancer (LSCRC), both metastatic and non-metastatic, and the results are also compared with those previously obtained for right sided tumors (RSCRCs). Methods Eighteen LSCRCs were studied using qPCR to analyze the expression of both the proteoglycan core proteins and the enzymes involved in heparan sulfate chain biosynthesis. Certain HSPGs also carry chondroitin sulfate chains and so we also studied the genes involved in its biosynthesis. The expression of certain genes that showed significant expression differences were also analysed using immunohistochemical techniques. Results Changes in proteoglycan core proteins were dependent on their location, and the main differences between metastatic and non-metastatic tumors affected cell-surface glypicans, while other molecules were quite similar. Glypicans were also responsible for the main differences between RS- and LS- malignances. Regarding the biosynthesis of heparan sulfate chains, differential alterations in transcription depending on the presence or not of metastasis affected genes involved in the modification of uronic acid (epimerization and 2-O sulfation), and some isoforms responsible for sulfation of glucosamine (NDST1, HS6ST1). Moreover, in RSCRCs differences were preferentially found in the expression of genes involved in C6 and C3 sulfation of glucosamine, but not in NDSTs or SULFs. Finally, synthesis of chondroitin sulfate showed some alterations, which affected various steps, including polimerization and the modification of chains, but the main variations dependent on the presence of metastases were epimerization and 6C sulfation; however, when compared with RSCRCs, the essential divergences affected polymerization of the chains and the 6C sulfation of the galactosamine residue. Conclusions We evidenced alterations in the expression of HSPGs, including the expression of cell surface core proteins, many glycosiltransferases and some enzymes that modify the GAG chains in LSCRCs, but this was dependent on the metastatic nature of the tumor. Some of these alterations are shared with RSCRCs, while others, focused on specific gene groups, are dependent on tumor localization

'Artilysation' of endolysin λSa2lys strongly improves its enzymatic and antibacterial activity against streptococci

Endolysins constitute a promising class of antibacterials against Gram-positive bacteria. Recently, endolysins have been engineered with selected peptides to obtain a new generation of lytic proteins, Artilysins, with specific activity against Gram-negative bacteria. Here, we demonstrate that artilysation can also be used to enhance the antibacterial activity of endolysins against Gram-positive bacteria and to reduce the dependence on external conditions. Art-240, a chimeric protein of the anti-streptococcal endolysin λSa2lys and the polycationic peptide PCNP, shows a similar species specificity as the parental endolysin, but the bactericidal activity against streptococci increases and is less affected by elevated NaCl concentrations and pH variations. Time-kill experiments and time-lapse microscopy demonstrate that the killing rate of Art-240 is approximately two-fold higher compared to wildtype endolysin λSa2lys, with a reduction in viable bacteria of 3 log units after 10 min. In addition, lower doses of Art-240 are required to achieve the same bactericidal effect.This research study was supported by grants AGL2012-40194-C02-01 (Ministry of Science and Innovation, Spain), FEDER founds and GRUPIN14-139 (Program of Science, Technology and Innovation 2013–2017, Principado de Asturias, Spain), bacteriophage network FAGOMA and research grant 1.5.171.15N of the Research Foundation – Flanders (FWO). DG was a fellow of the Ministry of Science and Innovation, Spain. LR-R was a FWO Pegasus Marie Curie Fellow. PG, BM, RL and AR are members of the FWO Vlaanderen funded “Phagebiotics” research community (WO.016.14).Peer Reviewe

Bacteriophages: The Enemies of Bad Bacteria Are Our Friends!

Some bacteria can enter the human body and make people ill. Usually, these diseases can be cured by antibiotics, but sometimes bacteria are resistant to them, meaning that the antibiotics do not kill the bacteria. In these cases, bacteria become very dangerous. Bacteriophages are viruses that infect bacteria but are harmless to humans. To reproduce, they get into a bacterium, where they multiply, and finally they break the bacterial cell open to release the new viruses. Therefore, bacteriophages kill bacteria. Here, we explain how bacteriophages can be used to treat infectious diseases or to remove bacteria from other places where they are unwanted.Peer reviewedPeer Reviewe

Genetic Diversity of Stone Fruit Cultivars Preserved On-Farm in Southern Spain

Old traditional cultivars are valuable genetic resources for crop improvement, but a great number of them have disappeared in the past century. This study aimed to characterize traditional cultivars of different Prunus species collected in small family orchards in southwestern Spain and to evaluate their genetic diversity and relationships. One hundred and twelve accessions belonging to 36 traditional cultivar denominations were analyzed using eight SSR loci transferable across the genus Prunus. The most useful loci to analyze different Prunus species were UDP96-005, BPPCT-002, UDP98-410 and ps02a12. A total of 152 alleles were observed, and 112 were unique to certain species. Sixty-eight different genotypes were found, revealing the possible existence of homonyms among traditional cultivar names. The clustering analysis was consistent with the taxonomic classification of the different species studied and with the geographical origins of the accessions within each species. The results showed wide genetic variability of traditional cultivars of stone fruits grown in small family orchards, which highlights the need to preserve them using both in-situ and ex-situ strategies. Twenty-eight of these accessions are currently conserved ex-situ at the University of Sevilla, Spain. The use of highly transferable SSRs has been proven as efficient in multi-species surveys performed on-farm