A Simplified Elastic Model for Seismic Analysis of Earth-Retaining Structures with Limited Displacements

A simplified elastic model for analyzing static and dynamic interaction between earth-retaining structures and backfill within the range of small displacements is presented. The postulated model covers some of the available models as special cases. The model lends itself readily to the treatment of non-homogeneous backfills with elastic properties varying with depth. Internal (linear) damping in the backfill can be included without impairing the simplicity of the model. Radiation losses due to waves propagating horizontally in fills of semi-infinite extent are inherent to the postulated model. The solutions for some statical and dynamical problems of practical importance show satisfactory agreement with results based on the classical theory of elasticity

Effect of polymer emulsion of the bearing capacity of Aeolian sand under extreme confinement conditions

An experimental investigation, aimed at evaluating the improvement of Aeolian sand (from Saudi Arabia) when treated with low dosages of a vinyl acrylic (a polymer emulsion), is reported in this paper. Special attention is devoted to the influence of the lateral confinement, particularly in terms of compaction and bearing capacity (represented by CBR), for which a modification of the standard test has been developed trying to simulate extreme confinement conditions. Experimental results demonstrate that this kind of chemical stabilizers can be considered as a suitable alternative for these materials. The main modifications induced in the sand by this additive are highlighted and quantified by means of the modification achieved for different geotechnical properties as well as Scanning Electron Microscope (SEM) and Energy-Dispersive X-Ray Spectroscopy (EDX) analyses

Improvement of the bearing capacity of confined and unconfined cement-stabilized aeolian sand

The improvement reached on the compaction and bearing capacity of aeolian sand collected in Jeddah (Saudi Arabia) after its stabilization with Portland cement is evaluated, comparing the behavior for both treated and untreated samples. With the aim of using this type of soil in the construction of embankments for road or railway applications, the results obtained have been evaluated in terms of maximum dry density, optimum moisture content (compaction test) and bearing capacity (CBR). Special attention has been paid to the influence of the confining conditions on the results, scarcely analyzed in the literature, by comparing the load-displacement curves during penetration stage in the CBR tests for both confined and unconfined specimens. Different contents of Portland cement have been explored (out of 6% of dry soil weight) to stabilize this material. The results obtained show a clear linear correlation between of compaction characteristics and CBR respect to the percentage of cement, obtaining, as expected, higher improvement for treated-material with higher content of cement, also strongly influenced by the confinement state. Thanks to this treatment, it is possible to employ this material in applications with low-confinement support, which is impossible without a previous proper stabilization. Finally, two practical indices have been defined to measure the degree of improvement reached, involving both cement content and confinement

The relative age effect on physical fitness in preschool children

The aim of the present study was to investigate the existence of a relative age effect (RAE) on physical fitness of preschoolers. Anthropometry and physical fitness were assessed in 3147 children (3–5 years old) using the PREFIT battery. Based on the birth year, participants were divided into 3year groups (3-, 4- and 5-years). Within each year group, 4quarter groups were created: quarter 1, preschoolers born from January to March; quarter 2, from April to June; quarter 3, from July to September; quarter 4, from October to December. The MANCOVA analysis revealed a main effect of year group (Wilks’ λ = 0.383; F10,5996 = 369.64; p < 0.001, ηp 2 = 0.381) and of quarter (Wilks’ λ = 0.874; F15,8276.6 = 27.67; p < 0.001; ηp 2 = 0.044) over the whole battery of tests. To the best of our knowledge, this is the first study to report the existence of RAE at the preschool stage. In general, performance improved as the relative age increased (i.e., those born in quarter 1 performed better than those in the other quarters). Individualization strategies should be addressed within the same academic year not only in elementary or secondary years but also in preschoolers

FGF receptor genes and breast cancer susceptibility: results from the Breast Cancer Association Consortium

Background:Breast cancer is one of the most common malignancies in women. Genome-wide association studies have identified FGFR2 as a breast cancer susceptibility gene. Common variation in other fibroblast growth factor (FGF) receptors might also modify risk. We tested this hypothesis by studying genotyped single-nucleotide polymorphisms (SNPs) and imputed SNPs in FGFR1, FGFR3, FGFR4 and FGFRL1 in the Breast Cancer Association Consortium. Methods:Data were combined from 49 studies, including 53 835 cases and 50 156 controls, of which 89 050 (46 450 cases and 42 600 controls) were of European ancestry, 12 893 (6269 cases and 6624 controls) of Asian and 2048 (1116 cases and 932 controls) of African ancestry. Associations with risk of breast cancer, overall and by disease sub-type, were assessed using unconditional logistic regression. Results:Little evidence of association with breast cancer risk was observed for SNPs in the FGF receptor genes. The strongest evidence in European women was for rs743682 in FGFR3; the estimated per-allele odds ratio was 1.05 (95 confidence interval=1.02-1.09, P=0.0020), which is substantially lower than that observed for SNPs in FGFR2. Conclusion:Our results suggest that common variants in the other FGF receptors are not associated with risk of breast cancer to the degree observed for FGFR2. © 2014 Cancer Research UK

Un análisis exploratorio de la relación entre pobreza multidimensional y conflicto armado : el caso de Antioquia en Colombia

RESUMEN: Este artículo analiza la relación entre pobreza y conflicto armado en Antioquia, Colombia. El análisis de la pobreza está enmarcado en el enfoque de las capacidades de Sen, el cual conforma la base conceptual del índice de pobreza multidimensional (IPM) desarrollado por Alkire y Foster. El IPM es calculado con información derivada de la base de datos Sisbén, la cual se utiliza para seleccionar la población atendida por los programas de asistencia social del Gobierno colombiano. Este artículo consideró tres dimensiones de pobreza: estándares de vida, salud, y educación. El conflicto armado fue medido por medio de datos de conteo acerca de la ocurrencia de eventos de violencia registrados entre 1996 y 2010 en cada municipalidad de Antioquia. Luego, la relación entre la pobreza y el conflicto armado se analizó mediante métodos exploratorios y no paramétricos como las distribuciones kernel. Los resultados sugieren que el IPM es robusto con respecto a la elección del umbral de pobreza multidimensional. Los mapas de caja y bigotes sugieren que los pobres están localizados en las regiones periféricas de Antioquia. Las distribuciones kernel muestran que las áreas más afectadas por el conflicto, usualmente, tienen altos niveles de pobreza multidimensional.ABSTRACT: This paper analyses the relationship between poverty and armed conflict in Antioquia, Colombia. The poverty analysis it uses is framed according to Sen’s capability approach, which constitutes the conceptual basis for the Multidimensional Poverty Index (MPI) subsequently developed by Alkire and Foster. The MPI is measured employing data from the government database SISBEN, which is used by the Colombian authorities to identify beneficiaries of social assistance programmes. The paper considers three poverty dimensions: living standards, health, and education. Armed conflict is measured using count data on violent events recorded for every municipality in the Department of Antioquia between 1996 and 2010. The relationship between poverty and armed conflict is then analysed using exploratory and non-parametric methods such as kernel distributions. Results suggest that the MPI is robust when compared multidimensional cutoffs. The MPI box-plot maps suggest that poor people are located in Antioquia’s peripheral areas. Kernel distributions show that areas most affected by conflict tend to show higher levels of multidimensional poverty

Evidence that breast cancer risk at the 2q35 locus is mediated through IGFBP5 regulation.

GWAS have identified a breast cancer susceptibility locus on 2q35. Here we report the fine mapping of this locus using data from 101,943 subjects from 50 case-control studies. We genotype 276 SNPs using the 'iCOGS' genotyping array and impute genotypes for a further 1,284 using 1000 Genomes Project data. All but two, strongly correlated SNPs (rs4442975 G/T and rs6721996 G/A) are excluded as candidate causal variants at odds against &gt;100:1. The best functional candidate, rs4442975, is associated with oestrogen receptor positive (ER+) disease with an odds ratio (OR) in Europeans of 0.85 (95% confidence interval=0.84-0.87; P=1.7 × 10(-43)) per t-allele. This SNP flanks a transcriptional enhancer that physically interacts with the promoter of IGFBP5 (encoding insulin-like growth factor-binding protein 5) and displays allele-specific gene expression, FOXA1 binding and chromatin looping. Evidence suggests that the g-allele confers increased breast cancer susceptibility through relative downregulation of IGFBP5, a gene with known roles in breast cell biology