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This study analyzed the haplotype diversity along the genome of seven Spanish Beef Cattle populations within regions of 500 kb using the information provided by the BovineHD Beadchip. The results of the analysis pointed out a strong variability of the haplotype diversity across the genome, which is greatly conserved across populations. This strong concordance between populations suggests that the reasons behind it are intrinsic to the structure of the bovine genome and caused probably by the mutation or recombination rate. Nevertheless, some of the genomic regions with very large haplotype diversity are also due of genome assembly errors. © 2017 Elsevier B.V.

[EN] Two scientific schools have been in coexistence from the beginning of genetics, one of them searching for factors of inheritance and the other one applying biometrical models to study the relationships between relatives. With the development of molecular genetics, the possibilities of detecting genes having a noticeable effect in traits augmented. Some genes with large or medium effects were localized in animals, although the most common result was to detect markers linked to these genes, allowing the possibility of assisting selection programs with markers. When a large amount of simple and inexpensive markers were available, the SNPs, new possibilities were opened since they did not need the presence of genes of large or medium effect controlling a trait, because the whole genome was scanned. Using a large amount of SNPs permits having a prediction of the breeding value at birth accurate enough to be used in some cases, like dairy cattle, to halve its generation interval. In other animal breeding programs, the implementation of genomic selection is less clear and the way in which it can be useful should be carefully studied. The need for large populations for associating phenotypic data and markers, plus the need for repeating the process continuously, complicates its application in some cases. The implementation of the information provided by the SNPs in current genetic programs has led to the development of complex statistical tools, joining the efforts of the two schools, factorial and biometrical, that nowadays work closely related. (C) 2014 Elsevier B.V. All rights reserved., This work was partially funded by the Ministerio de Economia y Competitividad, Spain (Projects AGL2011-29831-C03-01 and CGL2012-39861-C02-02). We are grateful to Dr. Saif Agha for his useful comments.

Genomics has opened up exciting possibilities in the field of conservation genetics. Here we have dealt with three different aspects of the use of genomics in conservation. The first is a description of genetic relationships between individuals where we try to clarify the relationship between the identity by descent (IBD) and the identity by state (IBS) concepts. Then we also review the strategies that have been suggested for using genomic data for increasing the effectiveness of the management of conserved populations. In particular, we review the strategies aimed at maintaining within breed genetic diversity and those aimed at removing undesired introgression in order to rescue the original genetic background of a particular breed. © 2014 Elsevier B.V.

The conservation of farm animal resources is important for coping with future breeding needs and for facilitating the sustainable use of marginal areas. The increasing availability of molecular markers for most farm animal species and the development of techniques to analyse molecular variation is widening our capacity to characterise the genetic variation of breeds. In this paper we review the most popular molecular markers used in conservation and animal breeding studies, the different measures of genetic diversity that they provide, and their application for managing within-breed genetic diversity and for setting between-breed conservation priorities. We also address the relationship between genomic and marker heterozygosity, the relationship between molecular and quantitative measures of genetic diversity, and the characterization of breeds based on non-neutral markers. © 2008 Elsevier B.V. All rights reserved.

Accurate and early estimations are essential for effective decision making in software project management. Nowadays, classical estimation models are being replaced by data mining models due to their application simplicity and the rapid production of profitable results. In this work, a method for mining association rules that relate project attributes is proposed. It deals with the problem of discretizing continuous data in order to generate a manageable number of high confident association rules. The method was validated by applying it to data from a Software Project Simulator. The association model obtained allows us to estimate the influence of certain management policy factors on various software project attributes simultaneously.

This paper presents a new approach to 2nding representative patterns for dataset editing. The algorithm patterns by ordered projections (POP), has some interesting characteristics: important reduction of the number of instances from the dataset; lower computational cost (� (mn log n)) with respect to other typical algorithms due to the absence of distance calculations; conservation of the decision boundaries, especially from the point of view of the application of axis-parallel classi2ers. POP works well in practice withbothcontinuous and discrete attributes. The performance of POP is analysed in two ways: percentage of reduction and classi2cation. POP has been compared to IB2, ENN and SHRINK concerning the percentage of reduction and the computational cost. In addition, we have analysed the accuracy of k-NN and C4.5 after applying the reduction techniques. An extensive empirical study using datasets with continuous and discrete attributes from the UCI repository shows that POP is a valuable preprocessing method for the later application of any axis-parallel learning algorithm. ? 2002 Pattern Recognition Society. Published by Elsevier Science Ltd. All rights reserved.

This paper presents a generic natural language interface that can be applied to the teleoperation of di!erent kinds of complex interactive systems. Through this interface the operators can ask for simple actions or more complex tasks to be executed by the system. Complex tasks will be decomposed into simpler actions generating a network of actions whose execution will result in the accomplishment of the required task. As a practical application, the system has been applied to the teleoperation of a real mobile robot, allowing the operator to move the robot in a partially structured environment through natural language sentences.

Since applications of expert systems were typical in domains with no well defined models, qualitative methods for modelling and reasoning were soon developed. Most current qualitative reasoning programs derive the qualitative behaviour of a system by simulating a hand-crafted qualitative version of the differential equation that caracterizes the model of a system. This paper describes a method to construct a family of piecewise linear dynamical systems from the qualitative information contained in a model. We apply the dynamical system theory to deduce results about the behaviour of the family of dynamical systems constructed as a consequence of the qualitative model.

Mixed model methodology was used to estimate genetic and environmental trends over 23 years for the traits weaning weight and number of teats in three populations of Iberian pigs. Full genealogy was available. REML estimates of variance components were used to obtain the predicted breeding values. Annual rate of genetic trend was estimated as the regression of the yearly mean predicted breeding value on year. Environmental trend was directly obtained from the estimate of the effect of batch. Results obtained for weaning weight were consistent with positive selection differentials and the low selection intensity applied. Estimated environmental trends reflected a change to worse management conditions that occurred in the herd. However, the methodology seems to have failed to separate genetic from environmental effects correctly for teat number. The reason may be in the special characteristics of the trait, which is not normally distributed, and for which the theoretical genetic model may differ from that assumed in mixed model analysis.

This paper gives a general formulation of the two-strategy game under the assumption of assortment of encounters which results in a richer set of solutions than those previously proposed. Assortment can arise because encounters tend to occur between individuals more similar either genotypically or phenotypically. In the latter situation the analysis has shown that polymorphic and mixed strategies are equivalent, providing the same solution for the ESS. The dynamics of gene frequency change has been investigated in a diploid one locus, two allele model and the conditions are given for the appearance of polymorphic equilibria in situations where the criteria for spread of a rare gene and fixation of a common one agree with those derived by inclusive fitness arguments. © 1986 Academic Press Inc. (London) Ltd.