A Gene Selection Approach based on Clustering for Classification Tasks in Colon Cancer

Gene selection (GS) is an important research area in the analysis of DNA-microarray data, since it involves gene discovery meaningful for a particular target annotation or able to discriminate expression profiles of samples coming from different populations. In this context, a wide number of filter methods have been proposed in the literature to identify subsets of relevant genes in accordance with prefixed targets. Despite the fact that there is a wide number of proposals, the complexity imposed by this problem (GS) remains a challenge. Hence, this paper proposes a novel approach for gene selection by using cluster techniques and filter methods on the found groupings to achieve informative gene subsets. As a result of applying our methodology to Colon cancer data, we have identified the best informative gene subset between several one subsets. According to the above, the reached results have proven the reliability of the approach given in this paper

Marine meteorology and remote sensing in West Africa

Comunicación presentada en: West Africa NMHSs Directors Meeting celebrado del 17 al 19 de octubre de 2007 en Las Palmas de Gran Canaria

A data mining framework based on boundary-points for gene selection from DNA-microarrays: Pancreatic Ductal Adenocarcinoma as a case study

[EN] Gene selection (or feature selection) from DNA-microarray data can be focused on different techniques, which generally involve statistical tests, data mining and machine learning. In recent years there has been an increasing interest in using hybrid-technique sets to face the problem of meaningful gene selection; nevertheless, this issue remains a challenge. In an effort to address the situation, this paper proposes a novel hybrid framework based on data mining techniques and tuned to select gene subsets, which are meaningfully related to the target disease conducted in DNA-microarray experiments. For this purpose, the framework above deals with approaches such as statistical significance tests, cluster analysis, evolutionary computation, visual analytics and boundary points. The latter is the core technique of our proposal, allowing the framework to define two methods of gene selection. Another novelty of this work is the inclusion of the age of patients as an additional factor in our analysis, which can leading to gaining more insight into the disease. In fact, the results reached in this research have been very promising and have shown their biological validity. Hence, our proposal has resulted in a methodology that can be followed in the gene selection process from DNA-microarray data

Ensayo no aleatorizado de una intervención educativa basada en principios cognitivo-conductuales para pacientes con lumbalgia crónica inespecífica atendidos en fisioterapia de atención primaria

ResumenObjetivoValorar la influencia de una intervención educativa en la reducción del «miedo-evitación» (ME) y del «catastrofismo al dolor» (CAT) en población con lumbalgia crónica inespecífica (LCI) atendida en fisioterapia de atención primaria (AP).DiseñoEstudio cuasiexperimental.EmplazamientoCentros de salud (CS) del Distrito Sanitario Costa del Sol.ParticipantesPacientes con LCI entre 18-65años con comprensión del idioma español; ausencia de intervenciones educativas paralelas; ausencia de banderas rojas; ausencia de deterioro cognitivo y/o fibromialgia; ausencia de cirugía dorsolumbar, y tolerancia al ejercicio físico.IntervencionesEl grupo control recibió la EdE grupal habitual. El experimental recibió, además, un instrumento escrito para lectura domiciliaria, más la posterior puesta en común, aclaración de dudas y reestructuración de creencias y metas durante el desarrollo de las sesiones. Ambas intervenciones duraron unos 280min (7 sesiones de 40min).ResultadosLas variables principales incluyeron ME y CAT. Secundariamente se valoraron dolor y discapacidad. Algunas variables «sociodemográficas» y «relacionadas con el trastorno» fueron tenidas en cuenta en el análisis.Se observaron diferencias estadísticamente significativas en el grupo experimental versus control en la variación del ME −14 (−25,5; 0) vs −4 (−13; 0) (p=0,009), y del CAT −9 (−18; −4) vs −4,5 (−8,25; 0) (p=0,000). Igualmente se observaron diferencias en discapacidad (p=0,046), pero no en dolor (p=0,280).ConclusionesLos resultados deben ser considerados a la luz de las posibles limitaciones que plantea el estudio. Su naturaleza pragmática permitiría una potencial transferencia a la dinámica asistencial habitual.AbstractObjectiveTo assess the influence of an educational intervention in reducing «fear-avoidance» (FA) and «pain catastrophising» (CAT) in a population with unspecific chronic low back pain (UCLBP), attending physiotherapy in Primary Health Care. A pragmatic quasi-experimental study was conducted in Health Centres of a Costa del Sol Health District.DesignQuasi-experimental study.SettingPrimary Health Care physiotherapy Back Schools in Health Centres of a Costa del Sol Health District.ParticipantsThe selection criteria were: UCLBP; 18-65years; understanding of the Spanish language; absence of parallel educational interventions; absence of red flags; not showing cognitive impairment or fibromyalgia; absence of thoracic-lumbar surgery, and exercise tolerance.InterventionsThe control group received the usual Back Schools program. The experimental group also received a written document for home reading, plus the subsequent sharing, clarifying doubts, and beliefs and goals restructuring during the development of the sessions. Both interventions lasted about 280minutes (7 sessions×40min).ResultsThe main variables included FA and CAT. Pain and disability were also assessed. Some «demographic» and «related disorder» variables were considered in the analysis.Statistically significant differences were observed in the experimental group versus control, in the variation of FA −14 (−25.5; 0) vs −4 (−13; 0) (P=.009), and CAT −9 (−18; −4) vs −4,5 (−8.25; 0) (P=.000), were observed. Also differences in disability (P=.046), but not in pain (P=.280).ConclusionsThese results should be considered in light of possible limits imposed by the study. Its pragmatic nature would allow a potential transfer to usual care

An Ensemble Framework Coping with Instability in the Gene Selection Process

[EN] This paper proposes an ensemble framework for gene selection, which is aimed at addressing instability problems presented in the gene filtering task. The complex process of gene selection from gene expression data faces different instability problems from the informative gene subsets found by different filter methods. This makes the identification of significant genes by the experts difficult. The instability of results can come from filter methods, gene classifier methods, different datasets of the same disease and multiple valid groups of biomarkers. Even though there is a wide number of proposals, the complexity imposed by this problem remains a challenge today. This work proposes a framework involving five stages of gene filtering to discover biomarkers for diagnosis and classification tasks. This framework performs a process of stable feature selection, facing the problems above and, thus, providing a more suitable and reliable solution for clinical and research purposes. Our proposal involves a process of multistage gene filtering, in which several ensemble strategies for gene selection were added in such a way that different classifiers simultaneously assess gene subsets to face instability. Firstly, we apply an ensemble of recent gene selection methods to obtain diversity in the genes found (stability according to filter methods). Next, we apply an ensemble of known classifiers to filter genes relevant to all classifiers at a time (stability according to classification methods). The achieved results were evaluated in two different datasets of the same disease (pancreatic ductal adenocarcinoma), in search of stability according to the disease, for which promising results were achieved

Hand features extractor using hand contour – a case study

Hand gesture recognition is an important topic in natural user interfaces (NUI). Hand features extraction is the first step for hand gesture recognition. This work proposes a novel real time method for hand features recognition. In our framework we use three cameras and the hand region is extracted with the background subtraction method. Features like arm angle and fingers positions are calculated using Y variations in the vertical contour image. Wrist detection is obtained by calculating the bigger distance from a base line and the hand contour, giving the main features for the hand gesture recognition. Experiments on our own data-set of about 1800 images show that our method performs well and is highly efficient

Motivational Climate, Physical Self-Concept, and Social Relationships in Adolescents in Physical Education Classes: A Systematic Review

The aim of the present study was to provide a comprehensive summary of scientific evidence related with the influence on physical self-concept and prosocial behaviours in adolescents, taking into account the motivational climate generated in Physical Education classes by the teacher. Studies with similar samples have shown that special consideration must be given to the motivational climate of involvement with the task and the coach’s style in support of autonomy in a greater occurrence of prosocial behaviours in the sports context, which shows that the social context is the most important variable in the direction of moral behaviours. Following the application of a search protocol in the Web of Science (WoS) database, 131 articles were initially identified, with eight manuscripts finally being analysed according to previously established criteria for the various stages of the PRISMA checklist. Despite only a relatively small number of articles being available to have rigorously evaluated the topic of interest, analysed studies revealed a direct relationship between motivational climate and physical self-concept. In contrast, no relationship emerged with prosocial behaviour.Consejería de Desarrollo educativo y formación profesional de la Junta de Andalucía (Spain