Examinando por Autor "Montero, J"

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CK12, a rainbow trout chemokine with lymphocyte chemo-attractant capacity associated to mucosal tissues
(Elsevier, 2011) Montero, J; Ordás, MC; Alejo, A; Sevilla, N; Tafalla, C
Although many chemokine genes have been identified in rainbow trout (Oncorhynchus mykiss) as in other teleost species, almost no studies focused on their biological role have been conducted, despite the fact that no clear inferences as to their functions can be made based on their low similarity to mammalian counterparts. In the current work, we have studied the regulation of mRNA transcription and protein expression of CK12, a rainbow trout CC chemokine previously catalogued within the CCL19/21/25 phylogenetic group. Our studies revealed that CK12 is strongly expressed both at mRNA and protein level in mucosal tissues. Mature lymphocyte populations also express CK12 both at mRNA and protein levels. Concerning its biological activity, a significant chemotatic activity towards purified recombinant CK12 in unfractionated leukocyte populations was observed in the spleen, but not in head kidney or blood. Consequently, a binding assay revealed that the number of leukocytes capable of binding CK12 was much more elevated in spleen populations than in leukocyte populations from other organs. This binding capacity was only observed in small lymphocytes that should account for resident inactivated lymphocytes, in contrast to mature lymphocytes that were responsible for CK12 production. Around 36% of these small lymphocytes were IgM+ cells, of which 40% had a CK12 binding capacity. On the other hand, 10% of thymocytes were also capable of CK12 binding, suggesting that both T and B immature lymphocytes are recruited by CK12. This work constitutes the first description of a mucosal-associated chemokine in fish in which important aspects of its regulation and functionality are revealed. © 2011 Elsevier Ltd.
Consistency and stability in aggregation operators with data structure
(2013 Joint IFSA World Congress and NAFIPS Annual Meeting (IFSA/NAFIPS), 2013) Rojas, K; Gómez, D; Rodríguez, JT; Montero, J
In this work, we continue with a previous work in which we analyzed and defined notions of consistency, stability and continuity of a family of aggregation operators (FAO) when the data is unstructured. Here we use these concepts to tackle with aggregation problem for those situations in which the information or data that has to be aggregated has an inherent structure. In particular, we will focus on two structures that has received an important attention during last decades due to it application is different fields as Muticriteria Decision Analysis: The linear order structures and the hierarchical structures from a prioritized point of view.
Consistency and stability in aggregation operators: an application to missing data problems
(Aggregation Functions in Theory and in Practise: Proceedings of the 7th International Summer School on Aggregation Operators at the Public University of Navarra, Pamplona, Spain, July 16-20, 2013, 2013) Rojas, K; Gómez, D; Rodríguez, JT; Montero, J
An aggregation operator is usually defined as a real function A n such that, from n data items x 1, …, x n in [0,1], produces an aggregated value A n (x 1,…,x n ) in [0,1]. This definition can be extended to consider the whole family of operators for any n instead of a single operator for an specific n. This has led to the current standard definition [4, 15] of a family of aggregation operators (FAO) as a set {A n :[0,1]n → [0,1],n ∈ N}, providing instructions on how to aggregate collections of items of any dimension n. This sequence of aggregation functions {A n } n ∈ N is also called extended aggregation functions (EAF) by other authors.
Development of child's home environment indexes based on consistent families of aggregation operators with prioritized hierarchical information
(Fuzzy Sets and Systems, 2013-06-24) Rojas, K; Gómez, D; Montero, J; Rodríguez, JT
The interventions aimed at the early childhood are of a main interest in educational policy, since it is in this period when it is possible to produce a major impact in the subsequent human development. The quality of children's social environment is the main influence to consider in achieving sound child development, affecting throughout school life. For this reason, the development of child's environment indexes appears in a natural way in the evaluation of all kind of educational policy research and social programs. However, crisp measures and indexes, based on usual linear techniques, do not ensure an adequate representation of social reality, since this last has a fuzzy nature and a nonlinear behavior. The development of indexes can be seen as an aggregation problem. In this paper, we extend the notions of consistency and strict stability of a family of aggregation operators (FAO), proposed in a previous work of the authors for the case of an aggregation process in which the data have no particular structure, to the case in which the information has a prioritized hierarchical structure. This extended notion of strict stability is then used to address the construction of indexes. Particularly, we apply this approach to develop a construction method of child's home environment indexes in which a stable family of prioritized aggregation operators is used in order to ensure robustness of the aggregation process when the information has a lineal structure. These indexes are built using fuzzy data that fit into a hierarchical structure by means of a stable family of prioritized aggregation operators based on the prioritized operator formulated by Yager, where the order relationship over fuzzy information was defined by experts on child development.
Some properties of consistency in the families of aggregation operators
(Eurofuse 2011: Workshop on Fuzzy Methods for Knowledge-Based Systems, 2012) Rojas, K; Gómez, Daniel; Montero, J; Rodríguez, JT
Aggregation functions have been widely studied in literature. Nevertheless, few efforts have been dedicated to analyze those properties related with the family of operators in a global way. In this work, we analyze the stability in a family of aggregation operators The stability property for a family of aggregation operators tries to force a family to have a stable/continuous definition in the sense that the aggregation of n − 1 items should be similar to the aggregation of n items if the last item is the aggregation of the previous n − 1 items. Following this idea some definitions and results are given.
Specific regulation of the chemokine response to viral hemorrhagic septicemia virus (VHSV) at the entry site
(American Society for Microbiology, 2011) Montero, J; García, J; Ordás, MC; Casanova, I; González, A; Coll, J; Tafalla, C
The fin bases constitute the main portal of rhabdovirus entry into rainbow trout (Oncorhynchus mykiss), and replication in this first site strongly conditions the outcome of the infection. In this context, we studied the chemokine response elicited in this area in response to viral hemorrhagic septicemia virus (VHSV), a rhabdovirus. Among all the rainbow trout chemokine genes studied, only the transcription levels of CK10 and CK12 were significantly upregulated in response to VHSV. As the virus had previously been shown to elicit a much stronger chemokine response in internal organs, we compared the effect of VHSV on the gills, another mucosal site which does not constitute the main site of viral entry or rhabdoviral replication. In this case, a significantly stronger chemokine response was triggered, with CK1, CK3, CK9, and CK11 being upregulated in response to VHSV and CK10 and CK12 being down-modulated by the virus. We then conducted further experiments to understand how these different chemokine responses of mucosal tissues could correlate with their capacity to support VHSV replication. No viral replication was detected in the gills, while at the fin bases, only the skin and the muscle were actively supporting viral replication. Within the skin, viral replication took place in the dermis, while viral replication was blocked within epidermal cells at some point before protein translation. The different susceptibilities of the different skin layers to VHSV correlated with the effect that VHSV has on their capacity to secrete chemotactic factors. Altogether, these results suggest a VHSV interference mechanism on the early chemokine response at its active replication sites within mucosal tissues, a possible key process that may facilitate viral entry.
Stability in Aggregation Operators
(Advances in Computational Intelligence. IPMU 2012. Communications in Computer and Information Science, 2012) Rojas, K; Gómez, D; Montero, J; Rodríguez, JT
Aggregation functions have been widely studied in literature. Nevertheless, few efforts have been dedicated to analyze those properties related with the family of operators in a global way. In this work, we analyze the stability in a family of aggregation operators The stability property for a family of aggregation operators tries to force a family to have a stable/continuous definition in the sense that the aggregation of n − 1 items should be similar to the aggregation of n items if the last item is the aggregation of the previous n − 1 items. Following this idea some definitions and results are given.
Strictly stable families of aggregation operators
(Fuzzy Sets and Systems, 2013) Rojas, K; Gómez, D; Rodríguez, JT; Montero, J
In this paper we analyze the notion of family of aggregation operators (FAO), also refereed to as extended aggregation functions (EAF), i.e., a set of aggregation operators defined in the unit interval which aggregate several input values into a single output value. In particular, we address the key issue of the relationship that should hold between the operators in a family in order to understand that they properly define a consistent FAO. We focus on the idea of strict stability of a family of aggregation operators in order to propose an operative notion of consistency between operators of such a family. In this way, robustness of the aggregation process can be guaranteed. Some strict stability definitions for FAOs are proposed, leading to a classification of the main aggregation operators in terms of the properties they satisfy. Furthermore, we apply this approach to analyze the stability of some families of aggregation operators based on weights.