124 research outputs found

    Sistema de Información para Patrimonio Histórico

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    [ES] Los sistemas de información geográficos (SIG) permiten gestionar información referida a un territorio de forma eficiente, ágil y flexible. La gestión de información referida a elementos patrimoniales presenta un conjunto de requerimientos con características similares. Tanto en los procesos de documentación como en los de restauración y conservación es necesario ubicar gran cantidad de información sobre la superficie del elemento objeto de la actuación, permitiendo no solo su edición y visualización, sino incluso el análisis de dicha información.Este trabajo presenta el diseño de un sistema de información para patrimonio cultural que proporciona la funcionalidad anteriormente descrita, el cual partiendo de algunas ideas y formas de trabajo de los sistemas de onformación geográficos ha adaptado estas ideas a las representaciones utilizadas comúnmente en el campo delpatrimonio.[EN] Geographic information systems (GIS) allow us to manage information related to a territory in an efficient and flexible way. Management of information concerning cultural heritage presents a set of requirements which are similar to those. In processes such as documentation, restoration and preservation it is necessary to locate a wealth of information on the surface of the model on which we are working, not only allowing editing and displaying it, but even analysing such information.This paper presents a novel design of an information system for cultural heritage that provides the functionality described above, which starting from some ideas and working methods borrowed from GIS has adapted these ideas to representations commonly used in the field of cultural heritage.Este trabajo ha sido parcialmente financiado por la Consejería de Innovación Ciencia y Empresa de la Junta de Andalucía a través del proyecto de excelencia PE09-TIC-5276.Torres, JC.; Soler, F.; Cano, P.; León, A.; Luzón, V.; Martín, D. (2012). Sistema de Información para Patrimonio Histórico. Virtual Archaeology Review. 3(5):53-57. https://doi.org/10.4995/var.2012.4506OJS53573

    Mutation bias shapes the spectrum of adaptive substitutions

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    Evolutionary adaptation often occurs by the fixation of beneficial mutations. This mode of adaptation can be characterized quantitatively by a spectrum of adaptive substitutions, i.e., a distribution for types of changes fixed in adaptation. Recent work establishes that the changes involved in adaptation reflect common types of mutations, raising the question of how strongly the mutation spectrum shapes the spectrum of adaptive substitutions. We address this question with a codon-based model for the spectrum of adaptive amino acid substitutions, applied to three large datasets covering thousands of amino acid changes identified in natural and experimental adaptation in Saccharomyces cerevisiae, Escherichia coli, and Mycobacterium tuberculosis Using species-specific mutation spectra based on prior knowledge, we find that the mutation spectrum has a proportional influence on the spectrum of adaptive substitutions in all three species. Indeed, we find that by inferring the mutation rates that best explain the spectrum of adaptive substitutions, we can accurately recover the species-specific mutation spectra. However, we also find that the predictive power of the model differs substantially between the three species. To better understand these differences, we use population simulations to explore the factors that influence how closely the spectrum of adaptive substitutions mirrors the mutation spectrum. The results show that the influence of the mutation spectrum decreases with increasing mutational supply ([Formula: see text]) and that predictive power is strongly affected by the number and diversity of beneficial mutations

    ZnMgO-based UV photodiodes: a comparison of films grown by spray pyrolysis and MBE

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    Detecting the UV part of the spectrum is fundamental for a wide range of applications where ZnMgO has the potential to play a central role. The shortest achievable wavelength is a function of the Mg content in the films, which in turn is dependent on the growth technique. Moreover, increasing Mg contents lead to an electrical compensation of the films, which directly affects the responsivity of the photodetectors. In addition, the metal-semiconductor interface and the presence of grain boundaries have a direct impact on the responsivity through different gain mechanisms. In this work, we review the development of ZnMgO UV Schottky photodiodes using molecular beam epitaxy and spray pyrolysis, and we analyze and compare the physical mechanisms underlying the photodetector behavior. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

    Towards the growth of Cu2ZnSn1-xGexS4 thin films by a single-stage process : effect of substrate temperatura and composition

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    Cu2ZnSn1-xGexS4 (CZTGS) thin films prepared by flash evaporation of a Zn-rich Cu2ZnSn0.5Ge0.5S4 bulk compound in powder form, and a subsequent thermal annealing in S containing Ar atmosphere are studied. The effect of the substrate temperature during evaporation and the initial composition of the precursor powder on the growth mechanism and properties of the final CZTGS thin film are investigated. The microstructure of the films and elemental depth profiles depend strongly on the growth conditions used. Incorporation of Ge into the Cu2ZnSnS4 lattice is demonstrated by the shift of the relevant X-ray diffraction peaks and Raman vibrational modes towards higher diffraction angles and frequencies respectively. A Raman mode at around 348-351 cm-1 is identified as characteristic of CZTGS alloys for x = [Ge]/([Sn]+[Ge]) = 0.14-0.30. The supply of Ge enables the reduction of the Sn loss via a saccrifical Ge loss. This fact allows increasing the substrate temperature up to 350º C during the evaporation, forming a high quality kesterite material and therefore, reducing the deposition process to one single stag

    Observations of the Gamow-Teller resonance in the rare-earth nuclei above Gd 146 populated in β decay

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    13 págs.; 11 figs. ; 1 tab.The rare-earth region of the nuclear table around the quasi-doubly magic nucleus Gd146 is one of the very few places in which the Gamow-Teller (GT) resonance can be populated in β decay. The appropriate technique to study such a phenomenon is total absorption spectroscopy, thanks to which one can measure the B(GT) distribution in β-decay experiments even when it is very fragmented and lies at high excitation energy in the daughter nucleus. Results on the GT resonance measured in the β decay of the odd-Z, N=83 nuclei Tb148, Ho150, and Tm152 are presented in this work and compared with shell-model calculations. The tail of the resonance is clearly observed up to the limit imposed by the Q value. This observation is important in the context of the understanding of the >quenching> of the GT strength. ©2016 American Physical SocietyThe authors would like to thank the GSI accelerator crew and the MSEP group for their support. This work has been partially supported by the Spanish Ministry (Grants No. FPA2005-03993, No. FPA200806419-C02-01, No. FPA2011- 24553, No. FPA2012-32443, No. FPA2014-57196-C5, and No. FPA2014-52823-C2-1-P) and the Generalitat Valenciana (PROMETEOII/2014/019).Peer Reviewe

    From genotypes to organisms: State-of-the-art and perspectives of a cornerstone in evolutionary dynamics

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    Understanding how genotypes map onto phenotypes, fitness, and eventually organisms is arguably the next major missing piece in a fully predictive theory of evolution. We refer to this generally as the problem of the genotype-phenotype map. Though we are still far from achieving a complete picture of these relationships, our current understanding of simpler questions, such as the structure induced in the space of genotypes by sequences mapped to molecular structures, has revealed important facts that deeply affect the dynamical description of evolutionary processes. Empirical evidence supporting the fundamental relevance of features such as phenotypic bias is mounting as well, while the synthesis of conceptual and experimental progress leads to questioning current assumptions on the nature of evolutionary dynamics-cancer progression models or synthetic biology approaches being notable examples. This work delves into a critical and constructive attitude in our current knowledge of how genotypes map onto molecular phenotypes and organismal functions, and discusses theoretical and empirical avenues to broaden and improve this comprehension. As a final goal, this community should aim at deriving an updated picture of evolutionary processes soundly relying on the structural properties of genotype spaces, as revealed by modern techniques of molecular and functional analysis.Comment: 111 pages, 11 figures uses elsarticle latex clas

    Optical properties of ZnMgO films grown by spray pyrolysis and their application to UV photodetection

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    This work presents a comprehensive optical characterization of Zn1−xMgxO thin films grown by spray pyrolysis (SP). Absorption measurements show the high potential of this technique to tune the bandgap from 3.30 to 4.11 eV by changing the Mg acetate content in the precursor solution, leading to a change of the Mg-content ranging from 0 up to 35%, as measured by transmission electron microscopy-energy dispersive x-ray spectroscopy. The optical emission of the films obtained by cathodoluminescence and photoluminescence spectroscopy shows a blue shift of the peak position from 3.26 to 3.89 eV with increasing Mg incorporation, with a clear excitonic contribution even at high Mg contents. The linewidth broadening of the absorption and emission spectra as well as the magnitude of the observed Stokes shift are found to significantly increase with the Mg content. This is shown to be related to both potential fluctuations induced by pure statistical alloy disorder and the presence of a tail of band states, the latter dominating for medium Mg contents. Finally, metal–semiconductor–metal photodiodes were fabricated showing a high sensitivity and a blue shift in the cut-off energy from 3.32 to 4.02 eV, i.e., down to 308 nm. The photodiodes present large UV/dark contrast ratios (102 − 107), indicating the viability of SP as a growth technique to fabricate low cost (Zn, Mg)O-based UV photodetectors reaching short wavelengths

    Identidad, territorio y promocion de la salud

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    El presente trabajo se enmarca dentro de un proyecto de extensión que se desarrolla durante el 2012, acreditado y financiado por la UNLP, denominado “Identidad, territorio y salud. Construcción de identidades colectivas y transferencia institucional en torno al primer nivel de atención en el Barrio Federal de Ensenada”. Este barrio cuenta con una población aproximada de 480 habitantes y está ubicado en la zona de Gran La Plata, Pcia. de Buenos Aires. El objetivo del trabajo consiste en fortalecer la apropiación y promoción de la salud colectiva, entendida ésta como un proceso construido históricamente por cada sociedad, que se crea y recrea en todos los aspectos de la vida cotidiana de los sujetos. La propuesta metodológica se sustenta en un proceso dialógico entre los sujetos involucrados: vecinos de barrio Federal y los integrantes del equipo del trabajo extensionista. Desde este marco (pedagógico horizontal) desarrollamos actividades grupales de carácter lúdico-recreativo, que a primera vista no aparentan tener una relación con el proceso salud-enfermedad, propio del imaginario social, pero implícitamente, estarían abarcando y generando cambios en el significado asignado del mismo. Partimos de la idea de fortalecer el sentirse bien, no en el estricto sentido biológico, sino como aquella capacidad para crear momentos y actividades con pares en un mismo territorio y generando lazos entre vecinos y entre éstos y la institución de salud del barrio. De este modo, las actividades se desarrollan principalmente en la sala de espera de la unidad sanitaria y en la plaza circundante. Hemos definido tres líneas de trabajo: artístico, narrativo-plástico y de producción audiovisual y medioambiente. En los encuentros se trabaja con diferentes recursos, propios de disciplinas como música, plástica, teatro, danza, escultura, circo, artes audiovisuales, literatura, entre otros. El carácter interdisciplinario de este proyecto, conformado por estudiantes de las carreras de Trabajo Social y Antropología, un artista escultor y dirigido y coordinado por docentes y graduados de las Facultades de Ciencias Medicas, Humanidades y Ciencias de la Educación y Trabajo Social, enriquece las perspectivas de abordaje y fortalece la visión social, integral y colectiva de la salud. Consolidar acciones identitarias del barrio, generadas a partir de la promoción de la salud, es el principal desafío a alcanzar

    Are ‘Endurance’ Alleles ‘Survival’ Alleles? Insights from the ACTN3 R577X Polymorphism

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    Exercise phenotypes have played a key role for ensuring survival over human evolution. We speculated that some genetic variants that influence exercise phenotypes could be associated with exceptional survival (i.e. reaching ≥100years of age). Owing to its effects on muscle structure/function, a potential candidate is the Arg(R)577Ter(X) polymorphism (rs1815739) in ACTN3, the structural gene encoding the skeletal muscle protein α-actinin-3. We compared the ACTN3 R577X genotype/allele frequencies between the following groups of ethnically-matched (Spanish) individuals: centenarians (cases, n = 64; 57 female; age range: 100–108 years), young healthy controls (n = 283, 67 females, 216 males; 21±2 years), and humans who are at the two end-points of exercise capacity phenotypes, i.e. muscle endurance (50 male professional road cyclists) and muscle power (63 male jumpers/sprinters). Although there were no differences in genotype/allele frequencies between centenarians (RR:28.8%; RX:47.5%; XX:23.7%), and controls (RR:31.8%; RX:49.8%; XX:18.4%) or endurance athletes (RR:28.0%; RX:46%; XX:26.0%), we observed a significantly higher frequency of the X allele (P = 0.019) and XX genotype (P = 0.011) in centenarians compared with power athletes (RR:47.6%; RX:36.5%;XX:15.9%). Notably, the frequency of the null XX (α-actinin-3 deficient) genotype in centenarians was the highest ever reported in non-athletic Caucasian populations. In conclusion, despite there were no significant differences with the younger, control population, overall the ACTN3 genotype of centenarians resembles that of world-class elite endurance athletes and differs from that of elite power athletes. Our preliminary data would suggest a certain ‘survival’ advantage brought about by α-actinin-3 deficiency and the ‘endurance’/oxidative muscle phenotype that is commonly associated with this condition

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London
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