3,061 research outputs found

    The SOAR Gravitational Arc Survey - I: Survey overview and photometric catalogs

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    We present the first results of the SOAR (Southern Astrophysical Research) Gravitational Arc Survey (SOGRAS). The survey imaged 47 clusters in two redshift intervals centered at z=0.27z=0.27 and z=0.55z=0.55, targeting the richest clusters in each interval. Images were obtained in the g′g', r′r' and i′i' bands using the SOAR Optical Imager (SOI), with a median seeing of 0.83, 0.76 and 0.71 arcsec, respectively, in these filters. Most of the survey clusters are located within the Sloan Digital Sky Survey (SDSS) Stripe 82 region and all of them are in the SDSS footprint. Photometric calibration was therefore performed using SDSS stars located in our SOI fields. We reached for galaxies in all fields the detection limits of g∼23.5g \sim 23.5, r∼23r \sim 23 and i∼22.5i \sim 22.5 for a signal-to-noise ratio (S/N) = 3. As a by-product of the image processing, we generated a source catalogue with 19760 entries, the vast majority of which are galaxies, where we list their positions, magnitudes and shape parameters. We compared our galaxy shape measurements to those of local galaxies and concluded that they were not strongly affected by seeing. From the catalogue data, we are able to identify a red sequence of galaxies in most clusters in the lower zz range. We found 16 gravitational arc candidates around 8 clusters in our sample. They tend to be bluer than the central galaxies in the lensing cluster. A preliminary analysis indicates that ∼10\sim 10% of the clusters have arcs around them, with a possible indication of a larger efficiency associated to the high-zz systems when compared to the low-zz ones. Deeper follow-up images with Gemini strengthen the case for the strong lensing nature of the candidates found in this survey.Comment: 17 pages, 11 figures (most of them multi-panel) MNRAS (2013

    Produtividade do setor agrícola brasileiro (1991-2003): uma análise espacial

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    Agricultural productivity is characterized by location patterns, represented by the so-called spatial effects, namely, spatial heterogeneity and spatial dependence. This paper analyzes the spatial effects which exert influence on agricultural land productivity at three points in time – 1991, 1997 and 2003 – at the microregional level, using exploratory spatial data analysis (ESDA). The main finding shows that agricultural productivity is increasingly self-correlated in space, over time. Two high-high (HH) clusters are identified consistently: one of them is located in the State of São Paulo and parts of the Center-West region, while the other cluster (HH) lies in the Northeastern Coast.A produtividade agrícola é marcada por padrões de localização representados pelos chamados efeitos espaciais, a saber: a heterogeneidade espacial e a dependência espacial. Assim, este trabalho analisa os efeitos espaciais que exercem influência sobre a produtividade agrícola da terra para três momentos do tempo – 1991, 1997 e 2003 – em nível microrregional. Para isso, implementa-se a análise exploratória de dados espaciais. O principal resultado mostra que a produtividade agrícola está crescentemente autocorrelacionada no espaço ao longo do tempo. Dois clusters alto-alto (AA) são identificados consistentemente: um deles localiza-se no Estado de São Paulo e partes do Centro-Oeste, enquanto o outro cluster AA situa-se no litoral nordestino

    Biogeographical ancestry is associated with socioenvironmental conditions and infections in a Latin American urban population.

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    Racial inequalities are observed for different diseases and are mainly caused by differences in socioeconomic status between ethnoracial groups. Genetic factors have also been implicated, and recently, several studies have investigated the association between biogeographical ancestry (BGA) and complex diseases. However, the role of BGA as a proxy for non-genetic health determinants has been little investigated. Similarly, studies comparing the association of BGA and self-reported skin colour with these determinants are scarce. Here, we report the association of BGA and self-reported skin colour with socioenvironmental conditions and infections. We studied 1246 children living in a Brazilian urban poor area. The BGA was estimated using 370,539 genome-wide autosomal markers. Standardised questionnaires were administered to the children's guardians to evaluate socioenvironmental conditions. Infection (or pathogen exposure) was defined by the presence of positive serologic test results for IgG to seven pathogens (Toxocara spp, Toxoplasma gondii, Helicobacter pylori, and hepatitis A, herpes simplex, herpes zoster and Epstein-Barr viruses) and the presence of intestinal helminth eggs in stool samples (Ascaris lumbricoides and Trichiuris trichiura). African ancestry was negatively associated with maternal education and household income and positively associated with infections and variables, indicating poorer housing and living conditions. The self-reported skin colour was associated with infections only. In stratified analyses, the proportion of African ancestry was associated with most of the outcomes investigated, particularly among admixed individuals. In conclusion, BGA was associated with socioenvironmental conditions and infections even in a low-income and highly admixed population, capturing differences that self-reported skin colour miss. Importantly, our findings suggest caution in interpreting significant associations between BGA and diseases as indicative of the genetic factors involved

    Portuguese multidisciplinary recommendations for non-pharmacological and non-surgical interventions in patients with rheumatoid arthritis

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    BACKGROUND: Patients with rheumatoid arthritis (RA) report significant levels of disease impact, which are improved, but not fully abrogated by immunosuppressive therapy, even when remission is achieved. This imposes the need for adjuvant interventions targeting the uncontrolled domains of disease impact. Non-pharmacological interventions are widely used for this purpose, but they have not been the object of professional recommendations or guidelines. OBJECTIVE: To propose multidisciplinary recommendations to inform clinical care providers regarding the employment of non-pharmacological and non-surgical interventions in the management of patients with RA. METHODS: The EULAR standardized operating procedures for the development of recommendations were followed. First, a systematic literature review was performed. Then, a multidisciplinary Technical Expert Panel (TEP) met to develop and discuss the recommendations and research agenda. For each developed recommendation i) the level of evidence and grade of recommendation were determined, and ii) the level of agreement among TEP members was set. A recommendation was adopted if approved by ≥75% of the TEP members, and the level of agreement was considered high when ≥8. All relevant national societies were included in this construction process to attain their endorsement. RESULTS: Based on evidence and expert opinion, the TEP developed and agreed on five overarching principles and 12 recommendations for non-pharmacological and non-surgical interventions in patients with RA. The mean level of agreement between the TEP members ranged between 8.5 and 9.9. The recommendations include a broad spectrum of intervention areas, such as exercise, hydrokinesiotherapy, psychological interventions, orthoses, education, general management of comorbidities, among others; and they set the requirements for their application. CONCLUSIONS: These recommendations are based on the consensus judgment of clinical experts from a wide range of disciplines and patients' representatives from Portugal. Given the evidence for effectiveness, feasibility and safety, non-pharmacological and non-surgical interventions should be an integral part of standard care for people with RA. It is hoped that these recommendations should be widely implemented in clinical practice. The target audience for these recommendations includes all health professionals involved in the care of patients with RA. The target patient population includes adult Portuguese people with RA.publishersversionpublishe

    The influence of Fe2O3 doping on the pore structure and mechanical strength of TiO2-containing alumina obtained by freeze-casting

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    This work investigated TiO/FeO doped alumina prepared by the freeze-casting technique and using camphene as the solvent. Dendritic pores were formed in the TiO doped alumina, a structure conferred by the frozen camphene. Contrary to this trend, further FeO doping of TiO-containing alumina resulted in the formation of non-dendritic structures. This behavior was attributed to the higher density of α-FeO (5.24 g cm) when compared to α-AlO (3.95 g cm) and anatase TiO (3.89 g cm), which reduced critical solidification front velocity, thus forming material with different pore shape. FeO doping also improved the densification of TiO-alumina and inhibited the formation of cracks, reflected by superior mechanical strength with best results ∼150% higher for 10% FeO loaded samples as compared to TiO-alumina samples

    Effect of titania addition on the properties of freeze-cast alumina samples

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    This work investigated the behavior of TiO2-containing α-Al2O3 samples prepared by the freeze-casting technique. Camphene and liquid nitrogen were used as the solvent and cooling fluid, respectively. Camphene resulted in the formation of dendritic pores, in the direction of the freeze-casting cold front during sample preparation. The formation of β-Al2TiO5 phase occurred at 1300°C, and became more evident as the sintering temperatures reached 1500°C. The TiO2 loading did not affect the sample porosity at a given temperature, but it was detrimental in the case of mechanical properties under certain conditions. For instance, the flexural strength slightly improved with increasing the TiO2 loading and sintering temperature from 1100 to 1300°C. This effect was attributed to the occurrence of a more effective sintering of alumina. However, as the heat treatment temperature was raised from 1300 to 1500°C, the flexural strength did not increase as a function of the TiO2 loading, even though the densification occurred with loss of porosity. The loss of mechanical strength was found to be associated with the formation of microcracks which stemmed from the formation of β-Al2TiO5 phase for TiO2 loadings in excess of 4wt% at these high sintering temperatures

    Dansyl Fluorophore Functionalized Hierarchically Structured Mesoporous Silica Nanoparticles As Novel Latent Fingerprint Development Agents

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    A nanostructured hybrid material based on mesoporous silica nanoparticles (MCM-41) functionalized with chitosan and a fluorescent dye (dansylglycine), designated MCM-41@Ch@DnsGly, was synthesized and characterized with a view to its application for the visualization of latent fingerprints. These nanoparticles were applied as latent fingerprint developers for marks on surfaces of diverse chemical composition, topography, optical characteristics, and spatially variant nature, typical of forensically challenging evidence. For quality assessment of the enhanced fingermarks, the developed images were analyzed holistically using the UK Home Office scale, forensic protocols and, in terms of their constituent features (minutiae), using forensic software. Across a substantive collection of marks deposited on chemically diverse surfaces and subject to complex environmental and temporal histories, 94% of the enhanced images presented sufficient minutiae for comparison with model dactyloscopy images. This novel nanomaterial presents enhanced performance with significant promise for superior exploitation by forensic practitioners in the acquisition and analysis of crime scene evidence
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