1,163 research outputs found
Two new feature selection algorithms with rough sets theory
Rough Sets Theory has opened new trends for the development of the Incomplete Information Theory. Inside this one, the notion of reduct is a very significant one, but to obtain a reduct in a decision system is an expensive computing process although very important in data analysis and knowledge discovery. Because of this, it has been necessary the development of different variants to calculate reducts. The present work look into the utility that offers Rough Sets Model and Information Theory in feature selection and a new method is presented with the purpose of calculate a good reduct. This new method consists of a greedy algorithm that uses heuristics to work out a good reduct in acceptable times. In this paper we propose other method to find good reducts, this method combines elements of Genetic Algorithm with Estimation of Distribution Algorithms. The new methods are compared with others which are implemented inside Pattern Recognition and Ant Colony Optimization Algorithms and the results of the statistical tests are shown.IFIP International Conference on Artificial Intelligence in Theory and Practice - Knowledge Acquisition and Data MiningRed de Universidades con Carreras en Informática (RedUNCI
Pyridine Based Antitumour Compounds Acting at the Colchicine Site
[EN]Antimitotics binding at the colchicine site of tubulin are important antitumour and vascular disrupting agents. Pyridines and azines are privileged scaffolds in medicinal chemistry and in recent years many colchicine site ligands (CSL) have incorporated them into their structures with the aim of improving their pharmacokinetic and pharmacodynamics properties. CSL have been classified according to their chemical structures and the chemical structures of the pyridine and azine containing antimitotic compounds are described. The design principles behind the structural modifications and the achieved effect on the biological activity upon inclusion of these heterocycles are also discussed. Lessons from the achievements and failures have been extracted and future perspectives delineated
Two new feature selection algorithms with rough sets theory
Rough Sets Theory has opened new trends for the development of the Incomplete Information Theory. Inside this one, the notion of reduct is a very significant one, but to obtain a reduct in a decision system is an expensive computing process although very important in data analysis and knowledge discovery. Because of this, it has been necessary the development of different variants to calculate reducts. The present work look into the utility that offers Rough Sets Model and Information Theory in feature selection and a new method is presented with the purpose of calculate a good reduct. This new method consists of a greedy algorithm that uses heuristics to work out a good reduct in acceptable times. In this paper we propose other method to find good reducts, this method combines elements of Genetic Algorithm with Estimation of Distribution Algorithms. The new methods are compared with others which are implemented inside Pattern Recognition and Ant Colony Optimization Algorithms and the results of the statistical tests are shown.IFIP International Conference on Artificial Intelligence in Theory and Practice - Knowledge Acquisition and Data MiningRed de Universidades con Carreras en Informática (RedUNCI
Improving the k-NN method: rough set in edit training set
Rough Set Theory (RST) is a technique for data analysis. In this study, we use RST to improve the performance of k-NN method. The RST is used to edit and reduce the training set. We propose two methods to edit training sets, which are based on the lower and upper approximations.
Experimental results show a satisfactory performance of k-NN method using these techniques.Applications in Artificial Intelligence - Learning and Neural NetsRed de Universidades con Carreras en Informática (RedUNCI
What Emotions do Pre-university Students Feel when Engaged in Computational Thinking Activities?
Emotions affect how we acquire knowledge, being one of the causes of the demotivation generated at the time of studying a new field. Computer Science does not always pique the interest of young people, so we carry out an analysis of emotions that are present in primary and secondary school students, around 8-9 years old and 12-13 years old, who engage in Computational Thinking activities, considering the educational level, gender, and type of intervention, to understand why this lack of interest. The sessions were based on 1 hour of face-to-face class in which activities related to Computational Thinking were carried out. The instrument used to measure emotions was the Developmental Channels Questionnaire which includes 13 different emotions that students must answer using the Likert scale from 0 to 10. The emotions felt have been mostly positive and ambiguous, while negative emotions have a low intensity, particularly in primary education. Regarding the educational level, there are differences between girls and boys only in the secondary education, while in the primary they are no significant. Also, girls show an evolution when carrying out this type of activity, while boys do not change
Establecimiento de la glycine (Neonotonia wightii) con fertilizante mineral, estiércol vacuno y cal en suelos Ferralíticos y Fersialíticos
Because of its high raw protein content, and adaptation to different agroecosystems, Glycine is one of the most extended legumes over the country; nevertheless, it needs fertile and not too acid soils. In Camagüey province, most of cattle raising areas are located on soils whose fertility and pH are medium to low; for that reason, two experiments were carried out in glass-house conditions to determine the effect of three soil fertility improvers on Glycine (Neonotonia wightii) cv. Tinaroo, behavior in fersialitic and ferralitic soils. Pots of 1,5 kg of capacity were used to study three doses of mineral fertilizer, cattle manure and lime in a randomized design with a factorial arrangement and four repetitions, evaluated by a double classification variance test (P≤ 0,05) and when there were significant differences Dunca'ns multiple range test was applied for comparison in case of significant differences (P≤ 0,05). Significant increases in Glycine yields were detected when applying the three mentioned improvers, while the highest dry matter production (8,23 and 21,54 g/pot) was registered with 50 t/ha of cattle manure combined to intermediate P-K doses (50-100 and 100-200 kg/ha for ferralitic and fersialitic soils) in addition to 2 t/ha CaCo3. Moreover, Glycine showed suitable contents of raw protein (15,69 and 18,80 %) and calcium (0,86 and 1,44 %) for animal normal growing up.Por sus altos contenidos en proteína bruta y su adaptabilidad a diferentes agroecosistemas, la Glycine es una de las leguminosas que más se ha extendido por todo el país; pero requiere de suelos fértiles y no muy ácidos. En Camagüey la mayoría de las áreas ganaderas están ubicadas en suelos de fertilidad y pH de medios a bajos, por lo que en condiciones de casa de cristal se condujeron dos experimentos para determinar el efecto de tres mejoradores de la fertilidad del suelo sobre el establecimiento de la Glycine (Neonotonia wightii) cv. Tinaroo, en suelos Ferralíticos y Fersialíticos. En macetas de 1,5 kg de capacidad se estudiaron tres dosis de fertilizante mineral, estiércol vacuno y cal (CaCO3) en cada suelo, mediante un diseño completamente aleatorizado con arreglo factorial y cuatro repeticiones, que se evaluaron por análisis de varianza de doble clasificación (P≤ 0,05) y en los casos de significación las medias se compararon por la prueba de rango múltiple de Duncan (P≤ 0,05). Se encontró que los rendimiento aumentaron significativamente con la aplicación de los tres mejoradores y que las mayores producciones de materia seca (8,23 y 21,54 g/maceta) se obtuvieron con el empleo de dosis equivalentes a 50 t/ha de estiércol vacuno combinado con la dosis intermedia de P-K (50-100 y 100-200 kg/ha para el suelo Ferralítico y Fersialítico, respectivamente) así como cuando se añadieron 2 t/ha de CaCO3. Además se encontró que esta especie muestra contenidos adecuados de proteína bruta (15,69 y 18,80 %) y calcio (0,86 y 1,44 %) para el normal desarrollo de los animales
The Masked Polar Group Incorporation (MPGI) Strategy in Drug Design: Effects of Nitrogen Substitutions on Combretastatin and Isocombretastatin Tubulin Inhibitors
[EN] Colchicine site ligands suffer from low aqueous solubility due to the highly hydrophobic nature of the binding site. A new strategy for increasing molecular polarity without exposing polar groups—termed masked polar group incorporation (MPGI)—was devised and applied to nitrogenated combretastatin analogues. Bulky ortho substituents to the pyridine nitrogen hinder it
from the hydrophobic pocket while increasing molecular polarity. The resulting analogues show improved aqueous solubilities and highly potent antiproliferative activity against several cancer cell lines of different origin. The more potent compounds showed moderate tubulin polymerization inhibitory activity, arrested the cell cycle of treated cells at the G2/M phase, and subsequently caused apoptotic cell death represented by the cells gathered at the subG0/G1 population after 48 h of treatment. Annexin V/Propidium Iodide (PI) double-positive cells observed after 72 h confirmed the induction of apoptosis. Docking studies suggest binding at the colchicine site of tubulin in a similar way as combretastatin A4, with the polar groups masked by the vicinal substituents. These results validate the proposed strategy for the design of colchicine site ligands and open a new road to
increasing the aqueous solubility of ligands binding in apolar environments
Protein crystallization in short-peptide supramolecular hydrogels: A versatile strategy towards biotechnological composite materials
Protein crystallization in hydrogels has been explored with the main purpose of facilitating the growth of high quality crystals while increasing their size to enhance their manipulation. New avenues are currently being built for the use of protein crystals as source materials to create sensors and drug delivery vehicles, to name just a few. In this sense, short-peptide supramolecular hydrogels may play a crucial role in integrating protein crystals within a wider range of applications. In this article, we show that protein crystallization in short-peptide supramolecular hydrogels is feasible and independent of the type of peptide that forms the hydrogel and/or the protein, although the output is not always the same. As a general trend, it is confirmed that hydrogel fibers are always incorporated within crystals so that novel composite materials for biotechnological applications with enhanced properties are produced.This research was funded by the MICINN (Spain) projects
BIO2010-6800 (JAG), CTQ2012-34778 (JJDM), and “Factoría
Española de Cristalización” Consolider-Ingenio 2010 (JAG &
MCM), and by Junta de Andalucía (Spain) project P12-FQM-
2721 (LAC). EDRF funds JAG, LAC & JMC. JJDM thanks
MICINN for a Ramon y Cajal Fellowship and MCM thanks
CSIC for her JAE Fellowshi
OBSERVATORIO TERRITORIAL Y AMBIENTAL ALENTEJO, EXTREMADURA, CENTRO (OTALEX C): DE GIS A IDE.
In the scope of the Spain-Portugal INTERREG projects and FEDER funded POCTEP program, OTALEX C (Territorial and Environmental Monitoring Alentejo Extremadura Center) project aims at studying of various territorial, socioeconomic and environmental indicators. It is the fundamental objective of this project, to develop a geo-portal accessible via internet, for anyone, so that the information will be useful in making decisions related to land use and therefore sustainable development of the environment.
Under this general framework over the past fifteen years, we have developed different projects that have set the standardization of data between Portugal and Spain, also was designed GIS systems, and developed regional models and indicator systems, culminating in the current Spatial Data Infrastructure SDI-OTALEX C
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