Modeling human behavior in user-adaptive systems: recent advances using soft computing techniques

Adaptive Hypermedia systems are becoming more important in our everyday activities and users are expecting more intelligent services from them. The key element of a generic adaptive hypermedia system is the user model. Traditional machine learning techniques used to create user models are usually too rigid to capture the inherent uncertainty of human behavior. In this context, soft computing techniques can be used to handle and process human uncertainty and to simulate human decision-making. This paper examines how soft computing techniques, including fuzzy logic, neural networks, genetic algorithms, fuzzy clustering and neuro-fuzzy systems, have been used, alone or in combination with other machine learning techniques, for user modeling from 1999 to 2004. For each technique, its main applications, limitations and future directions for user modeling are presented. The paper also presents guidelines that show which soft computing techniques should be used according to the task implemented by the application

P652The cardioprotective effect of exogenous sphingosine-1-phosphate requires the activation of endogenous sphingosine-1-phosphate via the sphingosine kinase 1

Purpose: Exogenous administration of sphingosine-1-phosphate (S1P) alone, or as part of high density lipoprotein, protects against myocardial infarction. S1P-induced cardioprotection targets the inhibition of the mitochondrial permeability transition pore via mechanisms that remain unclear. In the cell, the endogenous production of S1P from sphingosine is dependent on the activation of sphingosine kinases (SphK) 1 and 2. These two kinases play a role in cardioprotection against ischemia-reperfusion (IR) injury. Therefore, we hypothesised that the cardioprotective effect of exogenous S1P requires the activation of endogenous S1P via SphK. Methods: Isolated cardiomyocytes from adult wildtype mice were exposed to 2 hours of simulated ischemia (SI) in the presence of S1P (10nM) with/without N,N-dimethylsphingosine (DMS, a SphK1 and 2 inhibitor, 10μM) or SKI (a specific SphK1 inhibitor, 15μM). Cell viability was assessed using trypan blue staining and normalised to the normoxic control. Isolated perfused hearts from adult wildtype mice were exposed to 35 minutes of global ischemia followed by 45 minutes of reperfusion (IR) in the presence of S1P (10nM) with/without SKI (10μM). Infarct size (IS) was assessed using tripheyltetrazolium chloride staining and SphK1 activity using a specific biochemical fluorescence based assay kit. Both parameters were normalised to the IR control. Results: In isolated cardiomyocytes, viability under normoxic conditions was 76±1%. SI reduced viability to 52±1% (p< 0.001 vs. normoxia). Pre-treatment with S1P restored the viability to 75±1% (p<0.001 vs. SI). The beneficial effect of S1P was partially inhibited in the presence of DMS (67±4%) (ns vs. S1P) and totally abrogated with SKI pre-treatment (54±2%). Similarly, pre-treatment with S1P in isolated hearts reduced IS following IR from 50±1% (IR control) to 31±2% (S1P) (p<0.001 vs. control). Pre-treatment with SKI abrogated the cardioprotective effect of S1P (56±8%) (p<0.05 vs. S1P) as well as the S1P-induced increase in SphK1 activity (from S1P: 196±79 arbitrary units (AU) to SKI+S1P: 53±27 AU, p<0.05 vs. S1P). Conclusions: Our data, performed in both isolated cardiomyocytes and isolated hearts subjected to an ischemia/reperfusion insult, strongly suggest that exogenous sphingosine-1-phosphate-induced cardioprotection is dependent on the activation of endogenous sphingosine-1-phosphate via sphingosine kinase

On the construction of explosive relation algebras

Fork algebras are an extension of relation algebras obtained by extending the set of logical symbols with a binary operator called fork. This class of algebras was introduced by Haeberer and Veloso in the early 90's aiming at enriching relation algebra, an already successful language for program specification, with the capability of expressing some form of parallel computation. The further study of this class of algebras led to many meaningful results linked to interesting properties of relation algebras such as representability and finite axiomatizability, among others. Also in the 90's, Veloso introduced a subclass of relation algebras that are expansible to fork algebras, admitting a large number of non-isomorphic expansions, referred to as explosive relation algebras. In this work we discuss some general techniques for constructing algebras of this type

Stochastics theory of log-periodic patterns

We introduce an analytical model based on birth-death clustering processes to help understanding the empirical log-periodic corrections to power-law scaling and the finite-time singularity as reported in several domains including rupture, earthquakes, world population and financial systems. In our stochastics theory log-periodicities are a consequence of transient clusters induced by an entropy-like term that may reflect the amount of cooperative information carried by the state of a large system of different species. The clustering completion rates for the system are assumed to be given by a simple linear death process. The singularity at t_{o} is derived in terms of birth-death clustering coefficients.Comment: LaTeX, 1 ps figure - To appear J. Phys. A: Math & Ge

Genetic background influences murine prostate gene expression: implications for cancer phenotypes

Microarray analyses to quantitate transcript levels in the prostates of five inbred mouse strains identified differences in gene expression in benign epithelium that correlated with the differentiation state of adjacent tumors

Delivery of the 135kb human frataxin genomic DNA locus gives rise to different frataxin isoforms

© 2015 Elsevier Inc. Friedreich's ataxia (FRDA) is the most common form of hereditary ataxia caused by recessive mutations in the FXN gene. Recent results have indicated the presence of different frataxin isoforms due to alternative gene expression mechanisms. Our previous studies demonstrated the advantages of using high-capacity herpes simplex virus type 1 (HSV-1) amplicon vectors containing the entire FXN genomic locus (iBAC-FXN) as a gene-delivery vehicle capable of ensuring physiologically-regulated and long-term persistence. Here we describe how expression from the 135. kb human FXN genomic locus produces the three frataxin isoforms both in cultured neuronal cells and also in vivo. Moreover, we also observed the correct expression of these frataxin isoforms in patient-derived cells after delivery of the iBAC-. FXN. These results lend further support to the potential use of HSV-1 vectors containing entire genomic loci whose expression is mediated by complex transcriptional and posttranscriptional mechanisms for gene therapy applications.Spanish National Research Plan (SAF 2012-38042) and the Autonomous Government of Madrid (S2010/BMD-2331). The Center for Biomedical Research on Rare Diseases (“Centro de Investigación Biomédica en Red sobre Enfermedades Raras”, CIBERER) is an initiative supported by the “Instituto de Salud Carlos III”.Peer Reviewe

Geodesign, eco-brutalist artefacts for architecture, tourism and urbanism

Geodesign project is a co-promotion project funded by the Portugal 2020 program with the aim of developing new architectural products, integrating industrial waste and by-products generated by Portuguese companies, namely in the fields of steel, smelting, power stations, metallurgy and glassmaking. The partners of the project are W2V, SA, dedicated to waste management activities, Providência Design, dedicated to product design, the CVR technology center and the Portuguese universities of Minho and Trás-os-Montes and Alto Douro. Fly ash from thermoelectric plants, aluminum anodizing sludge and glass polishing dusts, among others, offer different plastic and chromatic qualities. When chemically integrated in the form of geopolymers or calcium-based materials, they exhibit different physical qualities of mechanical strength and aging. Taking into account their physical qualities and, consequently, the diversity of chromatic, textural and economical results, several functional products for wall covering, sound barriers and exterior furniture with expressive aesthetic impact were designed. Exploring the plastic qualities of a new brutalist, recyclable and sustainable aesthetic, a generation of artifacts was born that presents competitive advantages in the range of products for hotel, tourist architecture and urban planning in general. It will be the design of this brutalist aesthetic that, communicating sustainability, will be the factor of evidence to motivate the circularity of the economy and social inversion of the unsustainability of industrial consumption. The project provides for the technological test of development of new materials containing residues, their small-scale manufacturing and pre-industrial validation, after evaluating their economic and environmental impacts.W2V, SA; Francisco M. Providência, Lda; Geodesigninfo:eu-repo/semantics/publishedVersio