Combining privileged information to improve context-aware recommender systems

A recommender system is an information filtering technology which can be used to predict preference ratings of items (products, services, movies, etc) and/or to output a ranking of items that are likely to be of interest to the user. Context-aware recommender systems (CARS) learn and predict the tastes and preferences of users by incorporating available contextual information in the recommendation process. One of the major challenges in context-aware recommender systems research is the lack of automatic methods to obtain contextual information for these systems. Considering this scenario, in this paper, we propose to use contextual information from topic hierarchies of the items (web pages) to improve the performance of context-aware recommender systems. The topic hierarchies are constructed by an extension of the LUPI-based Incremental Hierarchical Clustering method that considers three types of information: traditional bag-of-words (technical information), and the combination of named entities (privileged information I) with domain terms (privileged information II). We evaluated the contextual information in four context-aware recommender systems. Different weights were assigned to each type of information. The empirical results demonstrated that topic hierarchies with the combination of the two kinds of privileged information can provide better recommendations.FAPESP (grant #2010/20564-8, #2012/13830-9, and #2013/16039-3, São Paulo Research Foundation (FAPESP))CAPE

In silico Studies Combining QSAR Models, DFT-based Reactivity Descriptors and Docking Simulations of Phthalimide Congeners with Hypolipidemic Activity

In this current study, a selected group of physicochemical descriptors extracted from the formalism of the density functional theory were used for modeling a series of phthalimide congeners with tested hypolipidemic activity once. Based on unsupervised pattern recognition of HCA and PCA followed by the PLS regressions, the final content may be considered trustful for predicting the biological activity due to the results of r2cal = 0.937, r2CV = 0.591 and r2test = 0.85. Moreover, the molecular modeling was performed through the docking protocol for predicting the ligand pose on the HMG-CoA reductase. The protocols of the AutoDock Tools and AutoDock Vina were used for determining the interaction scores (ΔG) and inhibition constants (Ki). Among all congeners studied, the docking results pointed out a potential compound. By taking into account the widely known top selling drugs, and just as is well-known that atorvastatin is one of them due its capability to lower the cholesterol levels, the structure of this drug was subjected to a docking study in order to guide us to a better understanding of the results available here. DOI: http://dx.doi.org/10.17807/orbital.v13i3.149

Application of remote sensing to the study of the pelagic spiny lobster larval transport in the Tropical Atlantic

A conectividade de populações marinhas através da dispersão larval é crucial para a manutenção da produção pesqueira e da biodiversidade. A dispersão de larvas ocorre em diferentes escalas espaciais e temporais, de forma que o recobrimento global e escala sinóptica fazem dos dados de satélite ferramentas importantes para esses estudos. O objetivo deste artigo é apresentar os resultados do uso de dados de correntes geostróficas derivadas de satélites altímetros para simular o transporte de larvas de lagosta espinhosa no oceano Atlântico Tropical. As simulações foram realizadas ao longo do Atlântico Tropical (20ºN - 15ºS), iniciando em quatro locais (Cabo Verde, Costa do Marfim, Ilha de Ascensão e Arquipélago de Fernando de Noronha). Foi utilizado um modelo advectivo/difusivo forçado com o campo médio de circulação geostrófica calculado entre 2001 e 2005 e outro forçado com campo correspondente ao evento de El Niño 2002/2003. Os resultados obtidos sugerem que há uma intensificação de processos oceânicos de meso-escala durante o ano de El Niño, que promove a conectividade entre diferentes estoques e aumenta as chances de ocorrer um fluxo genético. Os dados de correntes geostróficas gerados a partir de satélites altímetros incorporados a um modelo advectivo/difusivo simples podem prover informações importantes acerca da dinâmica física necessárias para conduzir estudos sobre dispersão larval.The connectivity of marine populations via larval dispersal is crucial for the maintenance of fisheries production and biodiversity. Because larval dispersion takes place on different spatial scales, global operational satellite data can be successfully used to investigate the connectivity of marine populations on different spatial and temporal scales. In fact, satellite data have long been used for the study of the large and mesoscale biological processes associated with ocean dynamics. This paper presents simulations of spiny lobster larvae transport in the Tropical Atlantic using the geostrophic currents, generated by altimetry that feeds an advection/diffusion model. Simulations were conducted over the Tropical Atlantic (20ºN to 15ºS), considering four larvae release areas: the Cape Verde Archipelago, the Ivory Coast, Ascension Island and Fernando de Noronha Archipelago. We used mean geostrophic current (MGC) calculated from 2001 to 2005 to represent the mean circulation of the Tropical Atlantic. We also ran the model for the El Niño geostrophic current regime (ENGC) using part of the MGC data, representing the El Niño 2002/2003 event. Results suggest that the intensification of the mesoscale ocean processes associated with El Niño events promotes the connectivity between populations, increasing the chances of a genetic flux among different stocks. We concluded that the altimetry geostrophic current data together with a relatively simple advection/diffusion model can provide useful information about the physical dynamics necessary to conduct studies on larval dispersion

Glatiramer Acetate Treatment Increases Stability Of Spinal Synapses And Down Regulates Mhc I During The Course Of Eae.

The recent discovery that the major histocompatibility complex of class I (MHC I) expression has a role in the synaptic elimination process, represented an insight into understanding the cross talk between neurons. In the present study, the possibility that glatiramer acetate (GA) treatment influences the MHC class I expression and the synaptic plasticity process in the spinal cord during the course of EAE was investigated. C57BL/6J mice were induced to EAE and submitted to treatment either with a placebo solution or with GA (0.05 mg/animal, subcutaneously, on a daily basis). All the animals were sacrificed at the peak disease (14 days after induction) or at the point of recovery of the clinical signs (21 days after induction). The spinal cords were removed and submitted to immunohistochemical examination, Western blotting and transmission electron microscopy analysis. The results showed that GA treatment was able to decrease synaptic loss during the course of EAE, which correlates with the downregulation of the MHC I complex. The present results reinforce the neuroprotective role of GA treatment, by reducing synaptic loss during the course of the disease. Such action may be associated with the recently described role of MHC I regulation during the synaptic plasticity process.71188-20

Aerobic Swim Training Restores Aortic Endothelial Function by Decreasing Superoxide Levels in Spontaneously Hypertensive Rats

OBJECTIVE: We aimed to determine whether aerobic training decreases superoxide levels, increases nitric oxide levels, and improves endothelium-dependent vasodilation in the aortas of spontaneously hypertensive rats. METHODS: Spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY) were distributed into 2 groups: sedentary (SHRsd and WKYsd, n=10 each) and swimming-trained (SHRtr, n=10 and WKYtr, n=10, respectively). The trained group participated in training sessions 5 days/week for 1 h/day with an additional work load of 4% of the animal’s body weight. After a 10-week sedentary or aerobic training period, the rats were euthanized. The thoracic aortas were removed to evaluate the vasodilator response to acetylcholine (10-10 to 10-4 M) with or without preincubation with L-NG-nitro-L-arginine methyl ester hydrochloride (L-NAME; 10-4 M) in vitro. The aortic tissue was also used to assess the levels of the endothelial nitric oxide synthase and nicotinamide adenine dinucleotide oxidase subunit isoforms 1 and 4 proteins, as well as the superoxide and nitrite contents. Blood pressure was measured using a computerized tail-cuff system. RESULTS: Aerobic training significantly increased the acetylcholine-induced maximum vasodilation observed in the SHRtr group compared with the SHRsd group (85.9±4.3 vs. 71.6±5.2%). Additionally, in the SHRtr group, superoxide levels were significantly decreased, nitric oxide bioavailability was improved, and the levels of the nicotinamide adenine dinucleotide oxidase subunit isoform 4 protein were decreased compared to the SHRsd group. Moreover, after training, the blood pressure of the SHRtr group decreased compared to the SHRsd group. Exercise training had no effect on the blood pressure of the WKYtr group. CONCLUSIONS: In SHR, aerobic swim training decreased vascular superoxide generation by nicotinamide adenine dinucleotide oxidase subunit isoform 4 and increased nitric oxide bioavailability, thereby improving endothelial function

Microsatellite markers for studies with the carnivorous plant Philcoxia minensis (Plantaginaceae)

Premise of the study: Microsatellite markers were developed for the critically endangered carnivorous species Philcoxia minensis (Plantaginaceae) for further population genetic studies aiming at its conservation. Methods and Results: We identifi ed 29 clones containing 40 microsatellites from a genomic enriched library. A total of 27 primer pairs were developed and evaluated in 30 individuals of a natural P. minensis population. Seventeen markers successfully presented amplifi cation products within the expected size range, of which 12 were polymorphic. The expected and observed heterozygosities ranged from 0.03 to 0.65 and from 0.00 to 0.77, respectively. Positive transferability with the related species P. bahiensis was observed for the same 17 markers. Conclusions: The 12 polymorphic microsatellite markers are suitable for studies in genetic diversity and structure, mating system, and gene fl ow in P. minensis and also may be useful for similar issues regarding the related species P. bahiensis38CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPSem informaçãoSem informação2012/12927-

Microsatellite Markers For Studies With The Carnivorous Plant Philcoxia Minensis (plantaginaceae).

Microsatellite markers were developed for the critically endangered carnivorous species Philcoxia minensis (Plantaginaceae) for further population genetic studies aiming at its conservation. We identified 29 clones containing 40 microsatellites from a genomic enriched library. A total of 27 primer pairs were developed and evaluated in 30 individuals of a natural P. minensis population. Seventeen markers successfully presented amplification products within the expected size range, of which 12 were polymorphic. The expected and observed heterozygosities ranged from 0.03 to 0.65 and from 0.00 to 0.77, respectively. Positive transferability with the related species P. bahiensis was observed for the same 17 markers. The 12 polymorphic microsatellite markers are suitable for studies in genetic diversity and structure, mating system, and gene flow in P. minensis and also may be useful for similar issues regarding the related species P. bahiensis.