1,654 research outputs found
ANDREU PINTADO, J. (ed.), Oppida Labentia, transformaciones, cambios y alteración en las ciudades hispanas entre el siglo II y la tardoantigüedad, Serie Monografías “Los Bañales”, Fundación Uncastillo, Uncastillo, 2017, 569 pp., ISBN: 978-84-617-9718-9. [RESEÑA]
Cryptanalysis of the RSA-CEGD protocol
Recently, Nenadi\'c et al. (2004) proposed the RSA-CEGD protocol for
certified delivery of e-goods. This is a relatively complex scheme based on
verifiable and recoverable encrypted signatures (VRES) to guarantee properties
such as strong fairness and non-repudiation, among others. In this paper, we
demonstrate how this protocol cannot achieve fairness by presenting a severe
attack and also pointing out some other weaknesses.Comment: 8 pages, 1 figur
Cryptic female choice favours sperm from major histocompatibility complex-dissimilar males
Cryptic female choice may enable polyandrous females to avoid inbreeding or bias offspring variability at key loci after mating. However, the role of these genetic benefits in cryptic female choice remains poorly understood. Female red junglefowl, Gallus gallus, bias sperm use in favour of unrelated males. Here, we experimentally investigate whether this bias is driven by relatedness per se, or by similarity at the major histocompatibility complex (MHC), genes central to vertebrate acquired immunity, where polymorphism is critical to an individual's ability to combat pathogens. Through experimentally controlled natural matings, we confirm that selection against related males' sperm occurs within the female reproductive tract but demonstrate that this is more accurately predicted by MHC similarity: controlling for relatedness per se, more sperm reached the eggs when partners were MHC-dissimilar. Importantly, this effect appeared largely owing to similarity at a single MHC locus (class I minor). Further, the effect of MHC similarity was lost following artificial insemination, suggesting that male phenotypic cues might be required for females to select sperm differentially. These results indicate that postmating mechanisms that reduce inbreeding may do so as a consequence of more specific strategies of cryptic female choice promoting MHC diversity in offspring
Recruitment of Immune Cells into Inflamed Tissues: Consequences for Endothelial Barrier Integrity and Tissue Functionality
Crossing the Vascular Wall: Common and Unique Mechanisms Exploited by Different Leukocyte Subsets during Extravasation
Leukocyte extravasation is one of the essential and first steps during the initiation of inflammation. Therefore, a better understanding of the key molecules that regulate this process may help to develop novel therapeutics for treatment of inflammation-based diseases such as atherosclerosis or rheumatoid arthritis. The endothelial adhesion molecules ICAM-1 and VCAM-1 are known as the central mediators of leukocyte adhesion to and transmigration across the endothelium. Engagement of these molecules by their leukocyte integrin receptors initiates the activation of several signaling pathways within both leukocytes and endothelium. Several of such events have been described to occur during transendothelial migration of all leukocyte subsets, whereas other mechanisms are known only for a single leukocyte subset. Here, we summarize current knowledge on regulatory mechanisms of leukocyte extravasation from a leukocyte and endothelial point of view, respectively. Specifically, we will focus on highlighting common and unique mechanisms that specific leukocyte subsets exploit to succeed in crossing endothelial monolayers
Proteoglycans in articular cartilage and their contribution to chondral injury and repair mechanisms
Proteoglycans are vital components of the extracellular matrix in articular cartilage, providing biomechanical properties crucial for its proper functioning. They are key players in chondral diseases, specifically in the degradation of the extracellular matrix. Evaluating proteoglycan molecules can serve as a biomarker for joint degradation in osteoarthritis patients, as well as assessing the quality of repaired tissue following different treatment strategies for chondral injuries. Despite ongoing research, understanding osteoarthritis and cartilage repair remains unclear, making the identification of key molecules essential for early diagnosis and effective treatment. This review offers an overview of proteoglycans as primary molecules in articular cartilage. It describes the various types of proteoglycans present in both healthy and damaged cartilage, highlighting their roles. Additionally, the review emphasizes the importance of assessing proteoglycans to evaluate the quality of repaired articular tissue. It concludes by providing a visual and narrative description of aggrecan distribution and presence in healthy cartilage. Proteoglycans, such as aggrecan, biglycan, decorin, perlecan, and versican, significantly contribute to maintaining the health of articular cartilage and the cartilage repair process. Therefore, studying these proteoglycans is vital for early diagnosis, evaluating the quality of repaired cartilage, and assessing treatment effectiveness
La implicación en la familia o en la empresa y su relación con la cooperación y la percepción del logro
Un nuevo modelo para abordar el protocolo familiar
Entender y gestionar la singularidad de la empresa familiar es determinante para mejorar las posibilidades de transmisión de la misma a generaciones futuras. Las estadísticas, año tras año, vienen a confirmar bajos índices de supervivencia en el traspaso generacional de la empresa familiar; Es por ello que desarrollar herramientas, que permitan y faciliten la comprensión y gestión de dicha singularidad, generará sin duda un fuerte valor añadido y ventaja competitiva para la familia empresaria en aras de mejorar su traspaso generacional y por tanto su supervivencia. El objetivo de este trabajo reside en la elaboración de un marco teórico para la aplicación del lienzo de modelo de negocios desarrollado por Alexander Osterwalder e Yves Pigneur (2008) modificado por nosotros y adaptado a la empresa familiar como un modelo de negocio en sí misma
- …