62 research outputs found

    The evolution of Balmer jump selected galaxies in the ALHAMBRA survey

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    We present a new color-selection technique, based on the Bruzual & Charlot models convolved with the bands of the ALHAMBRA survey, and the redshifted position of the Balmer jump to select star-forming galaxies in the redshift range 0.5 < z < 1.5. These galaxies are dubbed Balmer jump Galaxies BJGs. We apply the iSEDfit Bayesian approach to fit each detailed SED and determine star-formation rate (SFR), stellar mass, age and absolute magnitudes. The mass of the haloes where these samples reside are found via a clustering analysis. Five volume-limited BJG sub-samples with different mean redshifts are found to reside in haloes of median masses 1012.5±0.2M\sim 10^{12.5 \pm 0.2} M_\odot slightly increasing toward z=0.5. This increment is similar to numerical simulations results which suggests that we are tracing the evolution of an evolving population of haloes as they grow to reach a mass of 1012.7±0.1M\sim 10^{12.7 \pm 0.1} M_\odot at z=0.5. The likely progenitors of our samples at z\sim3 are Lyman Break Galaxies, which at z\sim2 would evolve into star-forming BzK galaxies, and their descendants in the local Universe are elliptical galaxies.Hence, this allows us to follow the putative evolution of the SFR, stellar mass and age of these galaxies. From z\sim1.0 to z\sim0.5, the stellar mass of the volume limited BJG samples nearly does not change with redshift, suggesting that major mergers play a minor role on the evolution of these galaxies. The SFR evolution accounts for the small variations of stellar mass, suggesting that star formation and possible minor mergers are the main channels of mass assembly.Comment: 14 pages, 10 figures. Submitted to A&A. It includes first referee's comments. Abstract abridged due to arXiv requirement

    Inappropriate prescribing to the oldest old patients admitted to hospital : prevalence, most frequently used medicines, and associated factors

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    Scientific evidence on treatments of chronic diseases in patients 85 years old or older is very limited, as is available information on inappropriate prescription (IP) and its associated factors. The study aimed to describe medicine prescription, potentially inappropriate medicines (PIM) and potentially prescribing omissions (PPO) and their associated factors on this population. In the context of an observational, prospective and multicentric study carried out in elderly patients admitted to seven Spanish hospitals for a year, a sub-analysis of those aged 85 years and over was performed. To assess PIMs, the Beers and STOPP criteria were used, and to assess PPOs, the START and the ACOVE-3 criteria were used. To assess factors associated with IP, a multivariate logistic regression analysis was performed. Patients were selected randomly every week on consecutive days from the hospitalization lists. A total of 336 patients were included in the sub-analysis with a median (Q1-Q3) age of 88 (86-90) years. The median medicines taken during the month prior to admission was 10 (7-13). Forty-seven point two per cent of patients had at least one Beers-listed PIM, 63.3% at least one STOPP-listed PIM, 53.6% at least one START-listed PPO, and 59.4% at least one ACOVE-3-listed PPO. Use of benzodiazepines in patients who are prone to falls (18.3%) and omission of calcium and vitamin D supplements in patients with osteoporosis (13.3%) were the most common PIM and PPO, respectively. The main factor associated with the Beers-listed and the STOPP-listed PIM was consumption of 10 or more medicines (OR = 5.7, 95% CI 1.8-17.9 and OR = 13.4, 95% CI 4.0-44.0, respectively). The main factors associated with the START-listed PPO was a non-community dwelling origin (OR 2.3, 95% CI 1.0-5.0), and multimorbidity (OR1.8, 95% CI 1.0-3.1). Prescribed medicines and PIM and PPO prevalence were high among patients 85 years and over. Benzodiazepine use in those who are prone to falls and omission of calcium and vitamin D in those with osteoporosis were the most frequent PIM and PPO, respectively. Factors associated with PIM and PPO differed with polypharmacy being the most important factor associated with PIM. The online version of this article (doi:10.1186/s12877-015-0038-8) contains supplementary material, which is available to authorized users

    The ALHAMBRA survey : BB-band luminosity function of quiescent and star-forming galaxies at 0.2z<10.2 \leq z < 1 by PDF analysis

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    Our goal is to study the evolution of the BB-band luminosity function (LF) since z=1z=1 using ALHAMBRA data. We used the photometric redshift and the II-band selection magnitude probability distribution functions (PDFs) of those ALHAMBRA galaxies with I24I\leq24 mag to compute the posterior LF. We statistically studied quiescent and star-forming galaxies using the template information encoded in the PDFs. The LF covariance matrix in redshift-magnitude-galaxy type space was computed, including the cosmic variance. That was estimated from the intrinsic dispersion of the LF measurements in the 48 ALHAMBRA sub-fields. The uncertainty due to the photometric redshift prior is also included in our analysis. We modelled the LF with a redshift-dependent Schechter function affected by the same selection effects than the data. The measured ALHAMBRA LF at 0.2z<10.2\leq z<1 and the evolving Schechter parameters both for quiescent and star-forming galaxies agree with previous results in the literature. The estimated redshift evolution of MBQzM_B^* \propto Qz is QSF=1.03±0.08Q_{\rm SF}=-1.03\pm0.08 and QQ=0.80±0.08Q_{\rm Q}=-0.80\pm0.08, and of logϕPz\log \phi^* \propto Pz is PSF=0.01±0.03P_{\rm SF}=-0.01\pm0.03 and PQ=0.41±0.05P_{\rm Q}=-0.41\pm0.05. The measured faint-end slopes are αSF=1.29±0.02\alpha_{\rm SF}=-1.29\pm0.02 and αQ=0.53±0.04\alpha_{\rm Q}=-0.53\pm0.04. We find a significant population of faint quiescent galaxies, modelled by a second Schechter function with slope β=1.31±0.11\beta=-1.31\pm0.11. We find a factor 2.55±0.142.55\pm0.14 decrease in the luminosity density jBj_B of star-forming galaxies, and a factor 1.25±0.161.25\pm0.16 increase in the jBj_B of quiescent ones since z=1z=1, confirming the continuous build-up of the quiescent population with cosmic time. The contribution of the faint quiescent population to jBj_B increases from 3% at z=1z=1 to 6% at z=0z=0. The developed methodology will be applied to future multi-filter surveys such as J-PAS.Comment: Accepted for publication in Astronomy and Astrophysics. 25 pages, 20 figures, 7 table

    Galaxy clusters and groups in the ALHAMBRA Survey

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    We present a catalogue of 348 galaxy clusters and groups with 0.2<z<1.20.2<z<1.2 selected in the 2.78 deg2deg^2 ALHAMBRA Survey. The high precision of our photometric redshifts, close to 1%1\%, and the wide spread of the seven ALHAMBRA pointings ensure that this catalogue has better mass sensitivity and is less affected by cosmic variance than comparable samples. The detection has been carried out with the Bayesian Cluster Finder (BCF), whose performance has been checked in ALHAMBRA-like light-cone mock catalogues. Great care has been taken to ensure that the observable properties of the mocks photometry accurately correspond to those of real catalogues. From our simulations, we expect to detect galaxy clusters and groups with both 70%70\% completeness and purity down to dark matter halo masses of Mh3×1013MM_h\sim3\times10^{13}\rm M_{\odot} for z<0.85z<0.85. Cluster redshifts are expected to be recovered with 0.6%\sim0.6\% precision for z<1z<1. We also expect to measure cluster masses with σMhMCL0.250.35dex\sigma_{M_h|M^*_{CL}}\sim0.25-0.35\, dex precision down to 3×1013M\sim3\times10^{13}\rm M_{\odot}, masses which are 50%50\% smaller than those reached by similar work. We have compared these detections with previous optical, spectroscopic and X-rays work, finding an excellent agreement with the rates reported from the simulations. We have also explored the overall properties of these detections such as the presence of a colour-magnitude relation, the evolution of the photometric blue fraction and the clustering of these sources in the different ALHAMBRA fields. Despite the small numbers, we observe tentative evidence that, for a fixed stellar mass, the environment is playing a crucial role at lower redshifts (z<<0.5).Comment: Accepted for publication in MNRAS. Catalogues and figures available online and under the following link: http://bascaso.net46.net/ALHAMBRA_clusters.htm

    A Ks-band-selected catalogue of objects in the ALHAMBRA survey

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    The original ALHAMBRA catalogue contained over 400,000 galaxies selected using a synthetic F814W image, to the magnitude limit AB(F814W)\approx24.5. Given the photometric redshift depth of the ALHAMBRA multiband data (=0.86) and the approximately II-band selection, there is a noticeable bias against red objects at moderate redshift. We avoid this bias by creating a new catalogue selected in the KsK_s band. This newly obtained catalogue is certainly shallower in terms of apparent magnitude, but deeper in terms of redshift, with a significant population of red objects at z>1z>1. We select objects using the KsK_s band images, which reach an approximate AB magnitude limit Ks22K_s \approx 22. We generate masks and derive completeness functions to characterize the sample. We have tested the quality of the photometry and photometric redshifts using both internal and external checks. Our final catalogue includes 95,000\approx 95,000 sources down to Ks22K_s \approx 22, with a significant tail towards high redshift. We have checked that there is a large sample of objects with spectral energy distributions that correspond to that of massive, passively evolving galaxies at z>1z > 1, reaching as far as z2.5z \approx 2.5. We have tested the possibility of combining our data with deep infrared observations at longer wavelengths, particularly Spitzer IRAC data

    Resultados del estudio geológico a escala 1/25.000 del término municipal de Madrid.

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    Se exponen de forma abreviada los rasgos en cuanto a metodología y conclusiones del estudio geológico a escala 1/25000 realizado en el Municipio de Madrid en los años 1982/83. Las diferentes unidades expresadas en la cartografiase describen en función de las pautas mayores observables en los materiales que forman cada una de ellas, analizándose sus relaciones estratigráficas. El Proyecto «Estudio Geológico a escala 1/25000 del Término Municipal de Madrid ha sido llevado a cabo a lo largo de los años 1982-83 como resultado de la colaboración científica entre diversos organismos de la Administración (Facultad de CC. Geológicas-Universidad Complutense, Instituto Geológico y Minero. Ayuntamiento de Madrid, Instituto de Geología de Madrid-CSIC, y otros). Constituye una de las áreas de actuación definidas dentro del Convenio de Colaboración Técnica y Cultural para el conocimiento de las Características del Suelo y Subsuelo de Madrid», propiciado y patrocinado por el Excmo. Ayuntamiento. La financiación del proyecto especifico de Geología ha sido realizada íntegramente por el IGME, organismo encargado además de su supervisión. El desarrollo del Proyecto tiene un marcado carácter interdisciplinar, fruto del trasvase de información entre los distintos grupos que abarca el Convenio general (aparte de los ya referidos, el SGOP, COPLACO, Laboratorio «José Luis Escario» siendo precisamente uno de los objetivos del trabajo el servir de apoyo a las restantes áreas de investigación. Los estudios geológicos realizados se plasman en un total de siete mapas a escala 1/25000 elaborados según la normativa Magna de cartografía geológica mapas que toman como referencia, aunque en algunos casos no las completan y en otros adosan porciones de hojas adyacentes, las hojas 1/25000 de Madrid, Alcorcón, El Pardo, San Femando de Henares, Pozuelo de Alarcón, Alcobendas y Castillo de Viñuelas

    2-Tridecanone impacts surface-associated bacterial behaviours and hinders plant-bacteria interactions

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    Surface motility and biofilm formation are behaviours which enable bacteria to infect their hosts and are controlled by different chemical signals. In the plant symbiotic alpha‐proteobacterium Sinorhizobium meliloti, the lack of long‐chain fatty acyl‐coenzyme A synthetase activity (FadD) leads to increased surface motility, defects in biofilm development, and impaired root colonization. In this study, analyses of lipid extracts and volatiles revealed that a fadD mutant accumulates 2‐tridecanone (2‐TDC), a methylketone known as a natural insecticide. Application of pure 2‐TDC to the wild‐type strain phenocopies the free‐living and symbiotic behaviours of the fadD mutant. Structural features of the methylketone determine its ability to promote S. meliloti surface translocation, which is mainly mediated by a flagella‐independent motility. Transcriptomic analyses showed that 2‐TDC induces differential expression of iron uptake, redox, and stress‐related genes. Interestingly, this methylketone also influences surface motility and impairs biofilm formation in plant and animal pathogenic bacteria. Moreover, 2‐TDC not only hampers alfalfa nodulation but also the development of tomato bacterial speck disease. This work assigns a new role to 2‐TDC as an infochemical that affects important bacterial traits and hampers plant‐bacteria interactions by interfering with microbial colonization of plant tissues
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