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Ruiz-Garzon G.,University of the Frontier | Dos Santos L.B.,University Federal Do Paran | Rufin-Lizana A.,University of Seville | Arana-Jimnez M.,University Cdiz
Computers and Mathematics with Applications | Year: 2010

This paper is devoted to the study of relationships between solutions of Stampacchia and Minty vector variational-like inequalities, weak and strong Pareto solutions of vector optimization problems and vector critical points in Banach spaces under pseudo-invexity and pseudo-monotonicity hypotheses. We have extended the results given by Gang and Liu (2008) [22] to Banach spaces and the relationships obtained for weak efficient points in Santos et al. (2008) [21] are completed and enabled to relate vector critical points, weak efficient points, solutions of the Minty and Stampacchia weak vector variational-like inequalities problems and solutions of perturbed vector variational-like inequalities problems. © 2010 Elsevier Ltd. All rights reserved.

Martinez-Cortes G.,University of Guadalajara | Nuno-Arana I.,University of Guadalajara | Rubi-Castellanos R.,University of Guadalajara | Vilchis-Dorantes G.,Laboratorio Of Genetica Forense | And 8 more authors.
Annals of Human Biology | Year: 2010

Background: CODIS-STRs in Native Mexican groups have rarely been analysed for human identification and anthropological purposes. Aim: To analyse the genetic relationships and population structure among three Native Mexican groups from Mesoamerica. Subjects and methods: 531 unrelated Native individuals from Mexico were PCR-typed for 15 and 9 autosomal STRs (Identifiler™ and Profiler™ kits, respectively), including five population samples: Purépechas (Mountain, Valley and Lake), Triquis and Yucatec Mayas. Previously published STR data were included in the analyses. Results: Allele frequencies and statistical parameters of forensic importance were estimated by population. The majority of Native groups were not differentiated pairwise, excepting Triquis and Purépechas, which was attributable to their relative geographic and cultural isolation. Although Mayas, Triquis and Purépechas-Mountain presented the highest number of private alleles, suggesting recurrent gene flow, the elevated differentiation of Triquis indicates a different origin of this gene flow. Interestingly, Huastecos and Mayas were not differentiated, which is in agreement with the archaeological hypothesis that Huastecos represent an ancestral Maya group. Interpopulation variability was greater in Natives than in Mestizos, both significant. Conclusion: Although results suggest that European admixture has increased the similarity between Native Mexican groups, the differentiation and inconsistent clustering by language or geography stresses the importance of serial founder effect and/or genetic drift in showing their present genetic relationships. © 2010 Informa UK, Ltd.

Sanchez P.,Hospital Psiquitrico Of Lava | Ojeda N.,Hospital Psiquitrico Of Lava | Ojeda N.,University of Deusto | Elizagarate E.,Hospital Psiquitrico Of Lava | And 8 more authors.
Revista de Psiquiatria y Salud Mental | Year: 2010

Introduction: There are no experimental data that demonstrate whether patients with neuroleptic-resistant schizophrenia differ or not in their pattern of neuropsychological functioning from patients with adequate drug response. Method: Fifty-two patients with drug-resistant psychosis (DRP) and 42 patients with schizophrenia not resistant to treatment (NDRP) were recruited following the criteria of Kane et al (1988). A sample of 45 healthy controls matched by age, sex and educational level was also recruited. The clinical evaluations used were the Positive and Negative Symptom Scale (PANSS), functional disability (WHO-DAS) and the Clinical Global Impression (CGI) scale. Results: Through the use of confirmatory factor analysis, we obtained a latent cognitive structure of six cognitive factors: attention, processing speed, verbal memory, working memory, verbal fluency and executive functions. As expected, the control group performed better than the two patient groups (both DRP and NDRP) in all neuropsychological domains. Additionally, the DRP group scored significantly worse in attention than the NDRP group even though no differences between these two groups were found in age of disease onset, number of hospitalizations or length of hospitalization. From a clinical point of view, the DRP group showed greater severity of positive symptoms (p<0.01) and higher global deterioration (p<0.01), which did not translate into greater functional disability. Conclusions: The results obtained do not allow us to conclude that there is a specific neuropsychological profile in neuroleptic-resistant patients. The only differential parameter was performance in the attentional domain. Our findings better fit the hypothesis of a «clinical continuum» and differ from the categoric classification of this mental disorder.

Guerrero-Lebrero M.P.,University Cdiz | Pizarro J.,University Cdiz | Guerrero E.,University Cdiz | Galindo P.L.,University Cdiz | And 2 more authors.
Journal of Physics: Conference Series | Year: 2010

High-Angle Annular Dark-Field Scanning Transmission Electron Microscopy (HAADF-STEM) in combination with strain mapping techniques provides a powerful tool for quantitative analysis of crystalline semiconductor materials. Due to the complex interaction of a focused probe and a sample in HAADF, the calculation of each pixel in a simulation process requires a complete multislice iteration, making the overall computing process a rather demanding task in time and memory. SICSTEM is a parallel software code recently developed for running on the University of Cadiz Supercomputer (3.75 Tflops) that allows the simulation of images from large nanostructures containing more than one million atoms. The software has been designed to be able to generate not only one dimensional line scans or two dimensional images, but also to perform optical sectioning in the STEM simulation process, providing an easy way to simulate 3D HAADF-STEM images. In this work we consider GaAs capped GaSb nanostructures epitaxially oriented on a GaAs substrate. A methodology has been developed by combining the through-focal series STEM imaging and image analysis to estimate shape and position of buried GaSb nanostructures. © 2010 IOP Publishing Ltd.

Lafuente L.,University Cdiz | Martinez-Raton Y.,Charles III University of Madrid
Journal of Statistical Mechanics: Theory and Experiment | Year: 2011

It is well known that increase of the spatial dimensionality enhances the fluid-fluid demixing of a binary mixture of hard hyperspheres, i.e.the demixing occurs for lower mixture size asymmetry as compared to the three-dimensional case. However, according to simulations, in the latter dimension the fluid-fluid demixing is metastable with respect to the fluid-solid transition. According to the results obtained from approximations to the equation of state of hard hyperspheres in higher dimensions, the fluid-fluid demixing might become stable for high enough dimension. However, this conclusion is rather speculative since none of these works have taken into account the stability of the crystalline phase (by a minimization of a given density functional, by spinodal calculations or by MC simulations). Of course, the lack of results is justified by the difficulty of performing density functional calculations or simulations in high dimensions and, in particular, for highly asymmetric binary mixtures. In the present work, we will take advantage of a well tested theoretical tool, namely the fundamental measure density functional theory for parallel hard hypercubes (in the continuum and in the hypercubic lattice). With this, we have calculated the fluid-fluid and fluid-solid spinodals for different spatial dimensions. We have obtained, no matter what the dimensionality, the mixture size asymmetry or the polydispersity (included as a bimodal distribution function centered around the asymmetric edge lengths), that the fluid-fluid critical point is always located above the fluid-solid spinodal. In conclusion, these results point to the existence of demixing between at least one solid phase rich in large particles and one fluid phase rich in small ones, preempting a fluid-fluid demixing, independently of the spatial dimension or the polydispersity. © 2011 IOP Publishing Ltd.

Gonzlez D.,University Cdiz | Lozano J.G.,University Cdiz | Herrera M.,University Cdiz | Morales F.M.,University Cdiz | And 3 more authors.
Nanotechnology | Year: 2010

Uncapped InN nanostructures undergo a deleterious natural aging process at ambient conditions by oxygen incorporation. The phases involved in this process and their localization is mapped by transmission electron microscopy (TEM)-related techniques. The parent wurtzite InN (InN-w) phase disappears from the surface and gradually forms a highly textured cubic layer that completely wraps up a InN-w nucleus which still remains from the original single-crystalline quantum dots. The good reticular relationships between the different crystals generate low misfit strains and explain the apparent easiness for phase transformations at room temperature and pressure conditions, but also disable the classical methods to identify phases and grains from TEM images. The application of the geometrical phase algorithm in order to form numerical moiré mappings and RGB multilayered image reconstructions allows us to discern among the different phases and grains formed inside these nanostructures. Samples aged for shorter times reveal the presence of metastable InN:O zinc blende (zb) volumes, which act as the intermediate phase between the initial InN-w and the most stable cubic In2O3 end phase. These cubic phases are highly twinned with a proportion of 50:50 between both orientations. We suggest that the existence of the intermediate InN:O-zb phase should be seriously considered to understand the reason for the widely scattered reported fundamental properties of thought to be InN-w, as its bandgap or superconductivity. © 2010 IOP Publishing Ltd.

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