Beatriz López

Bio: Beatriz López is an academic researcher from University of Girona. The author has contributed to research in topics: Case-based reasoning & Common value auction. The author has an hindex of 25, co-authored 119 publications receiving 2435 citations. Previous affiliations of Beatriz López include Spanish National Research Council & University of San Carlos.

A Taxonomy of Recommender Agents on theInternet

Abstract: Recently, Artificial Intelligence techniques have proved useful in helping users to handle the large amount of information on the Internet. The idea of personalized search engines, intelligent software agents, and recommender systems has been widely accepted among users who require assistance in searching, sorting, classifying, filtering and sharing this vast quantity of information. In this paper, we present a state-of-the-art taxonomy of intelligent recommender agents on the Internet. We have analyzed 37 different systems and their references and have sorted them into a list of 8 basic dimensions. These dimensions are then used to establish a taxonomy under which the systems analyzed are classified. Finally, we conclude this paper with a cross-dimensional analysis with the aim of providing a starting point for researchers to construct their own recommender system.

Tacripyrines, the first tacrine-dihydropyridine hybrids, as multitarget-directed ligands for the treatment of Alzheimer's disease.

Abstract: Tacripyrines (1−14) have been designed by combining an AChE inhibitor (tacrine) with a calcium antagonist such as nimodipine and are targeted to develop a multitarget therapeutic strategy to confront AD. Tacripyrines are selective and potent AChE inhibitors in the nanomolar range. The mixed type inhibition of hAChE activity of compound 11 (IC50 105 ± 15 nM) is associated to a 30.7 ± 8.6% inhibition of the proaggregating action of AChE on the Aβ and a moderate inhibition of Aβ self-aggregation (34.9 ± 5.4%). Molecular modeling indicates that binding of compound 11 to the AChE PAS mainly involves the (R)-11 enantiomer, which also agrees with the noncompetitive inhibition mechanism exhibited by p-methoxytacripyrine 11. Tacripyrines are neuroprotective agents, show moderate Ca2+ channel blocking effect, and cross the blood−brain barrier, emerging as lead candidates for treating AD.

Collaboration Analysis in Recommender Systems Using Social Networks

Abstract: Many researchers have focused their efforts on developing collaborative recommender systems. It has been proved that the use of collaboration in such systems improves performance, but what is not known is how this collaboration is done and what is more important, how it has to be done in order to optimise the information exchange. The collaborative relationships in recommender systems can be represented as a social network. In this paper we propose several measures to analyse collaboration based on social network analysis. Once these measures are explained, we use them to evaluate a concrete example of collaboration in a real recommender system.

Neuroprotective and cholinergic properties of multifunctional glutamic acid derivatives for the treatment of Alzheimer's disease.

Abstract: Novel multifunctional compounds have been designed, synthesized, and evaluated as potential drugs for the treatment of Alzheimer’s disease (AD). With an l-glutamic moiety as a suitable biocompatible linker, three pharmacophoric groups were joined: (1) an N-benzylpiperidine fragment selected to inhibit acetylcholinesterase by interacting with the catalytic active site (CAS), (2) an N-protecting group of the amino acid, capable of interacting with the acetylcholinesterase (AChE)-peripheral anionic site (PAS) and protecting neurons against oxidative stress, and (3) a lipophilic alkyl ester that would facilitate penetration into the central nervous system by crossing the blood−brain barrier. At submicromolar concentration, they inhibit AChE and butyrylcholinesterase (BuChE) of human origin, displace the binding of propidium iodide from the PAS of AChE, and could thus inhibit Aβ aggregation promoted by AChE. They also display neuroprotective properties against mitochondrial free radicals, show low toxicity, an...

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Case-based reasoning: foundational issues, methodological variations, and system approaches

Abstract: Case-based reasoning is a recent approach to problem solving and learning that has got a lot of attention over the last few years. Originating in the US, the basic idea and underlying theories have spread to other continents, and we are now within a period of highly active research in case-based reasoning in Europe, as well. This paper gives an overview of the foundational issues related to case-based reasoning, describes some of the leading methodological approaches within the field, and exemplifies the current state through pointers to some systems. Initially, a general framework is defined, to which the subsequent descriptions and discussions will refer. The framework is influenced by recent methodologies for knowledge level descriptions of intelligent systems. The methods for case retrieval, reuse, solution testing, and learning are summarized, and their actual realization is discussed in the light of a few example systems that represent different CBR approaches. We also discuss the role of case-based methods as one type of reasoning and learning method within an integrated system architecture.