214 research outputs found

    Wide-field HST/ACS images of M81: The Population of Compact Star Clusters

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    We study the population of compact stellar clusters (CSCs) in M81, using the HST/ACS images in the filters F435W, F606W and F814W covering, for the first time, the entire optical extent of the galaxy. Our sample contains 435 clusters of FWHM less than 10 ACS pixels (9 pc). The sample shows the presence of two cluster populations, a blue group of 263 objects brighter than B=22 mag, and a red group of 172 objects, brighter than B=24 mag. Based on the analysis of colour magnitude diagrams and making use of simple stellar population models, we find the blue clusters are younger than 300 Myr with some clusters as young as few Myr, and the red clusters are as old as globular clusters. The luminosity function of the blue group follows a power-law distribution with an index of 2.0, typical value for young CSCs in other galaxies. The power-law shows unmistakable signs of truncation at I=18.0 mag (M_I=-9.8 mag), which would correspond to a mass-limit of 4x10^4 M_solar if the brightest clusters are younger than 10 Myr. The red clusters have photometric masses between 10^5 to 2x10^7 M_solar for the adopted age of 5 Gyr and their luminosity function resembles very much the globular cluster luminosity function in the Milky Way. The brightest GC in M81 has M_B^0=-10.3 mag, which is ~0.9 mag brighter than w-Cen, the most massive GC in the Milky Way.Comment: Accepted by MNRAS. The paper contains 10 figures and 3 tables. Table 3 will be published in full online onl

    Environmental impact assessment of Pinaceae airborne pollen and green infrastructure using BIM

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    Urban air quality is a parameter that plays a major role in human health at the local scale. Consequently, in urban planning, the behavior and potential risk of allergenicity for some pollen grains coming from ornamental trees and green spaces surrounding newly built buildings, should be considered. This paper aims to study how pollen exposure, influenced by weather parameters, can be assessed and integrated in the designing and building of constructions as other component of air quality assessment beforehand, by using BIM. Based on a comparative aerobiological study at the height over a building (sampled by two traps at ground and at 16 m), a 3D local dynamic parametric scenario was modelled using BIM, and hourly average Pinaceae pollen concentrations (due to the closeness of pine trees to the samplers). From continuous recording (2009–2011) influenced by height and the influence of wind direction and speed was analysed. Additionally, a map of pine trees geolocated around the studied building was produced and the hourly average Pinaceae pollen concentrations were represented by Revit. BIM together with aerobiology can be a novel and useful tool for the construction of buildings considering airborne biological particles. This represents a first step towards the integration of some unusual environmental parameters in urban planning. Pollen grains modelling as an environmental health criterion for the construction of new buildings will allow technicians to avoid possible future isolation points in the design of building envelopes, and high pollen exposure rates could be avoided, creating ‘allergy-free’ buildings

    In situ assessment of carbon nanotube diameter distribution with photoelectron spectroscopy

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    7 págs.; 6 figs.; 1 tab. ; PACS numberssd: 73.22.2f, 79.60.Jv, 61.46.1wIn situ UV-photoelectron spectroscopy (He I and He II) was performed on multiwalled carbon nanotubes (CNTs) with clearly differentiated diameter distributions. A significant dependence of valence- and conduction-band characteristics on the mean CNT diameter was observed, which was determined by high-resolution TEM and micro-Raman spectroscopy. The decrease of relative intensity of the π states at -3 eV in the He II experiments, indicative of increasing rehybridization between orbitals, was directly correlated with decreasing mean diameters. Furthermore, a progressive broadening of the unoccupied σ* band at 7.6 eV was found in the He I spectra. © 2005 The American Physical Society.J.W.S. is grateful to the Centre Interdisciplinaire de Microscopie Electronique sCIMEd at the Ecole Polytechnique Fédérale de Lausanne sEPFLd for access to TEM and technical support. We also thank the National Centre of Competence in Research for Nanosciences NCCRd and the Swiss National Foundation for financial support.Peer Reviewe

    Inflammatory Animal Model for Parkinson's Disease: The Intranigral Injection of LPS Induced the Inflammatory Process along with the Selective Degeneration of Nigrostriatal Dopaminergic Neurons

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    We have developed an animal model of degeneration of the nigrostriatal dopaminergic neurons, the neuronal system involved in Parkinson's disease (PD). The implication of neuroinflammation on this disease was originally established in 1988, when the presence of activated microglia in the substantia nigra (SN) of parkinsonians was reported by McGeer et al. Neuroinflammation could be involved in the progression of the disease or even has more direct implications. We injected 2 μg of the potent proinflammatory compound lipopolysaccharide (LPS) in different areas of the CNS, finding that SN displayed the highest inflammatory response and that dopaminergic (body) neurons showed a special and specific sensitivity to this process with the induction of selective dopaminergic degeneration. Neurodegeneration is induced by inflammation since it is prevented by anti-inflammatory compounds. The special sensitivity of dopaminergic neurons seems to be related to the endogenous dopaminergic content, since it is overcome by dopamine depletion. Compounds that activate microglia or induce inflammation have similar effects to LPS. This model suggest that inflammation is an important component of the degeneration of the nigrostriatal dopaminergic system, probably also in PD. Anti-inflammatory treatments could be useful to prevent or slow down the rate of dopaminergic degeneration in this disease

    Urban aerobiological risk mapping of ornamental trees using a new index based on LiDAR and Kriging: A case study of plane trees

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    Ornamental trees bring benefits for human health, including reducing urban pollution. However, some species, such as plane trees (Platanus sp.), produce allergenic pollen. Consequently, urban maps are a valuable tool for allergic patients and allergists, but they often fail to include variables that contribute to the “building downwash effect”, such as the width and shape of streets and the height of buildings. Other factors that directly influence pollen dispersion (slopes and other geographical features) also have not traditionally been discussed. The LiDAR (Laser Imaging Detection and Ranging) technique enables one to consider these variables with high accuracy. This work proposes an Aerobiological Index to create Risk maps for Ornamental Trees (AIROT) and the establishment of potential areas of risk of exposure to Platanus pollen. LiDAR data from five urban areas were used to create the DEM and DSM (Digital Elevation and Surface Models) needed to perform further analysis. GIS software was used to map the points for each city and to create risk maps by Kriging, with stable (3 cases) and exponential function (2 cases) as the optimal models. In short, the AIROT index was a useful tool to map possible biological risks in cities. Since AIROT allows each city to consider its own characteristics, including geographical specifications, by using remote sensing and geostatistics techniques, the establishment of risk maps and healthy itineraries is valuable for allergic patients, allergists, architects and urban planners. This new aerobiological index provides a new decision-making tool related to urban planning and allergenicity assessment

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    Data mining identifies novel RNA-binding proteins involved in colon and rectal carcinomas

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    Colorectal adenocarcinoma (COREAD) is the second most deadly cancer and third most frequently encountered malignancy worldwide. Despite efforts in molecular subtyping and subsequent personalized COREAD treatments, multidisciplinary evidence suggests separating COREAD into colon cancer (COAD) and rectal cancer (READ). This new perspective could improve diagnosis and treatment of both carcinomas. RNA-binding proteins (RBPs), as critical regulators of every hallmark of cancer, could fulfill the need to identify sensitive biomarkers for COAD and READ separately. To detect new RBPs involved in COAD and READ progression, here we used a multidata integration strategy to prioritize tumorigenic RBPs. We analyzed and integrated 1) RBPs genomic and transcriptomic alterations from 488 COAD and 155 READ patients, 2) ∼ 10,000 raw associations between RBPs and cancer genes, 3) ∼ 15,000 immunostainings, and 4) loss-of-function screens performed in 102 COREAD cell lines. Thus, we unraveled new putative roles of NOP56, RBM12, NAT10, FKBP1A, EMG1, and CSE1L in COAD and READ progression. Interestingly, FKBP1A and EMG1 have never been related with any of these carcinomas but presented tumorigenic features in other cancer types. Subsequent survival analyses highlighted the clinical relevance of FKBP1A, NOP56, and NAT10 mRNA expression to predict poor prognosis in COREAD and COAD patients. Further research should be performed to validate their clinical potential and to elucidate their molecular mechanisms underlying these malignancies

    Insights onto the magnetic coupling at hexaferrite-based hard/soft bilayer systems

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    IBERTRIVA 2019 X Iberian Conference on Tribology – IBERTRIB, XI Iberian Vacuum Conference - RIVA, Seville, Spain,June 26-28Magnets are used in a variety of applications, such as generators, magnetic recording media, components in RF and microwave devices. However, many of these magnets contain s rare earths, critical elements whose extraction is environmentally harmful and that present price volatility risks. Their replacement by cheaper and more environmentally friendly materials is therefore sought. In our case, we have focused on magnetically hard strontium hexaferrite (SrFe 12O19, SFO) as the base for alternative permanent magnets (Figure 1a). The atomic arrangement of this ferrite results in a high magnetocrystalline anisotropy and a coercive field, however, its magnetization is moderate (1). It is well known that the coupling between a magnetically hard and soft material improved magnetization while avoiding a high cost in coercitivity loss (2). However, results have been disappointing so far as structural and geometrical limitations make it extremely challenging to fabricate. In this work, we aim at further understanding the magnetic coupling at hard -soft interfaces involving ferrites, for which we have deposited soft iron and cobalt metals on top of SrFe12O19 thin films with controlled easy-axis of magnetization. SFO thin films have been obtained by RF magnetron sputtering at 260W followed by a subsequent annealing in air of 850ºC. Their structure and composition was characterized by Raman spectroscospy (Figure 1b), Mössbauer spectroscopy, X-ray photoemission spectroscopy and low-energy electron microscopy (LEEM). We have grown the magnetically soft layer by molecular-beam epitaxy and we have analyzed the resulting bilayer system through photoemission electron microscopy, LEEM and vibrating-sample magnetometry. References [1] R.C. Pullar, Hexagonal ferrites: a review of the synthesis, properties and applications of hexaferrite ceramics, Progress in Materials Science 57 (2012), pp 1191¿1334. [2] Eric E. Fullerton, J. S. Jiang, M. Grimsditch, C. H. Sowers, and S. D. Bader, Exchange-spring behavior in epitaxial hard/soft magnetic bilayers, Phys. Rev. B 58 (1998) 1219

    Design of an innovative learning experience for the final project of the building engineering degree

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    This essay presents the bases for a new teaching methodology for the Final Project of the Degree of Building Engineering. The aim of this methodology is to approach students to advanced forms of work in architectural and engineering offices by employing Building Information Modelling (BIM) technologies. This initiative has been funded within the Call 2011 for Teaching Research Incentives ofthe I Teaching Plan of the University of Seville. Following the guidelines of the European Higher Education Area, the learning experience designed has to enable the future Building Engineers to acquire specific and generic competences ascribed to the Final Project in the Verification Report of the Building Engineering Degree. The specific competence “E71. Presentation and defence before a university board of a final project, consisting of an integration exercise of the formative contents received and skills acquired through t he degree” is trained by the development of a building execution project with the use of BIM technologies. For a decade, architecture and engineering offices have increasingly been incorporating in their projects new tools for information processing in digital integrated systems, i.e. programs which allow the construction of building virtual models in three dimensions, and the identification of their constructive components, providing them with parametric dimensions. The operating capacity of BIM programs is stronger than that of 2D drawing programs, since they can manage and generate all the technical documentation in an integrated way. As far as the generic competences are concerned, the problem is that the Final Project has ascribed twenty four competences and their training and evaluation throughout a single term, which seems rather unattainable. In order to solve this matter, the four most important generic competences of Building Engineers have been identified according to their professional profile: “G01. Capacity for organization and planning”, “G06. Information management skills”, “G09. Ability to work in an interdisciplinary team” and “G13. Positive social attitude towards social and technological innovations”. The use of BIM technologies and collaborative work methodologies allow the training of these genericcompetences. Finally, assessment matrixes of the five competences involved have been established with the descriptors of the assessment indicators for each of their corresponding criteria at each level of student achievement. This study is limited to the design of the experience; its implementation could be carried out in the first term of the 2012/2013 academic year, provided the main pre-requisite are met by students, and command of BIM programs such as ALLPLAN, REVIT or ARCHICAD, is achieved. Aware of this challenge− since BIM programs are taught as optional subjects− a curricular line for students interested in participating in this experience is also proposed for the next academic yea

    Red Consultiva Artesanal fase dos, V16

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    Este documento contiene diferentes aspectos para la generación de una red consultiva artesanal propuesta por Fundación con Causa Azul. El objetivo principal del proyecto es la generación de un sitio web que sirva como soporte para la red consultiva, en el cual se otorgue información y ofrezca un espacio de diálogo y reflexión referente al sector artesanal.ITESO, A.C.Fundación con Causa Azul, A. C
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