848 research outputs found
Notas sobre el tamaño del genoma en el híbrido Ranunculus x luizetii (Ranunculaceae) y sus progenitores mediante citometría de flujo
Notes on genome size in the hybrid Ranunculus x luizetii (Ranunculaceae) and its parents by flow cytometry.- Flow cytometry was used to estimate the nuclear DNA content in the natural hybrid Ranunculus x luizetii and its parents. Our results indicate that the genome size of the hybrid R. x luizetii is closer to R. pyrenaeus than to R. parnassiifolius, providing an evidence of genome downsizing.Notas sobre el tamaño del genoma en el híbrido Ranunculus x luizetii (Ranunculaceae) y sus progenitores mediante citometría de flujo.- Se ha empleado la citometría de flujo para estimar el contenido de ADN nuclear en el híbrido Ranunculus x luizetii y sus progenitores. Nuestros resultados indican que el tamaño del genoma del híbrido R. x luizetii se acerca más a R. pyrenaeus que a R. parnassiifolius, con una evidencia de reducción del genoma
Evaluation of the biodiversity in Bryophytes and Pteridophytes in Nueva’s river basin (Llanes, Asturias, North Iberian Peninsula): scientific grounds for its protection and conservation
El valle del río de Nueva, orientado al este, se encuentra muy próximo al mar Cantábrico. Su cuenca alta y media, con una superficie de 5,5 Km2, presenta una elevada biodiversidad de briófitos al haberse identificado 145 taxones (85 musgos,
59 hepáticas y 1 antocerota), lo que representa el 23% de la flora briofítica de Asturias. El muestreo realizado, por cuadrículas UTM de 0,5 Km de lado, nos revela también la riqueza en briófitos de este territorio, ya que se han contabilizado hasta 70 taxones distintos en cada unidad de cuadrícula. Del catálogo elaborado resultan ser novedad para la Península Ibérica Dicranodontium asperulum y, además, para el Principado de Asturias, los musgos: Dicranum scottianum y Plagiothecium platyphyllum, y las hepáticas: Bazzania trilobata var. depauperata, Cephalozia crassifolia, Cephalozia loitlesbergeri, Kurzia sylvatica, Lepidozia cupressina, Nowellia curvifolia y Jungermannia paroica, taxa, la mayoría, de reducida distribución. Se amplía el área de
distribución, a escala regional, de otras especies (15 hepáticas y 5 musgos) raras o amenazadas, incluidas en la «Red List of Bryophytes of the Iberian Peninsula» (Sérgio & al. 1994). Se ha realizado un estudio fitosociológico de las comunidades briopteridofíticas, en especial las presididas por helechos de carácter «subtropical» presentes en el área de estudio: Woodwardia radicans, Hymenophyllum tunbrigense, Culcita macrocarpa, Stegnogramma pozoi, Vandenboschia speciosa, etc. En su mayoría, estas comunidades pertenecen a la alianza Hymenophyllion tunbrigensis (Orden
Anomodonto-Polypodietalia, Clase Anomodonto-Polypodietea), que agrupa fitocenosis constituidas, fundamentalmente, por briófitos y pteridófitos, que colonizan repisas de peñascos, muros y taludes terrosos compactos sobre una delgada capa de
tierra (exocomófitos), desarrolladas en ambientes saturados de humedad ambiental, bajo el dosel de formaciones forestales. Mediante el cálculo de los índices de rareza específica, coeficiente de diversidad fitocenótica y calidad botánica, entre otros, se ha evaluado el territorio con el fin de sentar las bases científicas para su protección y conservación.Nueva’s River Valley lies close to the Cantabrico sea, facing towards the east. The upper and middle part of its basin, with a surface of 5.5 Km2, shows a high
diversity of bryophytes, as we have identified 145 taxa (85 mosses, 59 liverworts and 1 hornworts), which represent 23% of the Asturias bryophytic flora. The use as sampling unit UTM squares of 0.5 Km side, shows also the richness in bryophytes of this place, as we have found up to 70 different taxa in each square unit. From the catalogue made, Dicranodontium asperulum turns out to be new for the Iberian Peninsula, as in the same way for Principado de Asturias are the mosses Dicranum
scottianum and Plagiothecium platyphyllum, and the liverworts Bazzania trilobata var. depauperata, Cephalozia crassifolia, Cephalozia loitlesbergeri, Kurzia sylvatica, Lepidozia cupressina, Nowellia curvifolia and Jungermannia paroica. Most of these
taxa have very reduced distribution area. At the regional level, our data represent to enlarge the area of some other rare or threatened species (15 liverworts and 5 mosses), included in the «Red List of Bryophytes of the Iberian Peninsula» (Sérgio & al. 1994). A phytosociologic study of the bryo-pteridophytic communities has been made, especially on those dominated by ferns bearing «subtropical» character: Woodwardia
radicans, Hymenophyllum tunbrigense, Culcita macrocarpa, Stegnogramma pozoi, Vandenboschia speciosa, etc. Most of these communities belong to the alliance Hymenophyllion tunbrigensis (Order Anomodonto-Polypodietalia, Class Anomodonto-
Polypodietea). This alliance gathers phytocoenoses mainly made by bryophytes and pteridophytes, that inhabit sides of large rocks, walls and compact earth slopes, rootin in a thin layer of soil (exocomophytes), and developed in a really wet
environment, under the canopy of forest formations. Through calculation of the «Rare specific index», coefficient of diversity phytocenotics and of botanic quality, among others, we have evaluated the zone with the aim to lay the scientific grounds for its protection and conservation
Does Rising Income Inequality Reduce Life Expectancy?: New Evidence for 26 European Countries (1995-2014)
An open debate these days is about how national income inequality could affect individuals? health outcomes. Therefore, the present study aims to provide new evidence regarding life expectancy determinants and how they are related to the income inequality hypothesis. Precisely, it is provided new evidence on this relationship for 26 European countries during the period 1995?2014. The analysis is based on panel data techniques, with the latest data from both Eurostat and the OECD Health Statistics. Furthermore, data from the World Bank is also applied. Besides, we have tested the sensitivity of the estimates in our empirical analysis using three clusters of countries. Our results suggest that income inequality does not significantly reduce health in developed societies, like the European ones. Notwithstanding, as income inequality can be sometimes harmful for population health, these issues must be taken into account in order to improve health care policies
GLEAM v3 : satellite-based land evaporation and root-zone soil moisture
The Global Land Evaporation Amsterdam Model (GLEAM) is a set of algorithms dedicated to the estimation of terrestrial evaporation and root-zone soil moisture from satellite data. Ever since its development in 2011, the model has been regularly revised, aiming at the optimal incorporation of new satellite-observed geophysical variables, and improving the representation of physical processes. In this study, the next version of this model (v3) is presented. Key changes relative to the previous version include (1) a revised formulation of the evaporative stress, (2) an optimized drainage algorithm, and (3) a new soil moisture data assimilation system. GLEAM v3 is used to produce three new data sets of terrestrial evaporation and root-zone soil moisture, including a 36-year data set spanning 1980-2015, referred to as v3a (based on satellite-observed soil moisture, vegetation optical depth and snow-water equivalent, reanalysis air temperature and radiation, and a multi-source precipitation product), and two satellite-based data sets. The latter share most of their forcing, except for the vegetation optical depth and soil moisture, which are based on observations from different passive and active C-and L-band microwave sensors (European Space Agency Climate Change Initiative, ESA CCI) for the v3b data set (spanning 2003-2015) and observations from the Soil Moisture and Ocean Salinity (SMOS) satellite in the v3c data set (spanning 2011-2015). Here, these three data sets are described in detail, compared against analogous data sets generated using the previous version of GLEAM (v2), and validated against measurements from 91 eddy-covariance towers and 2325 soil moisture sensors across a broad range of ecosystems. Results indicate that the quality of the v3 soil moisture is consistently better than the one from v2: average correlations against in situ surface soil moisture measurements increase from 0.61 to 0.64 in the case of the v3a data set and the representation of soil moisture in the second layer improves as well, with correlations increasing from 0.47 to 0.53. Similar improvements are observed for the v3b and c data sets. Despite regional differences, the quality of the evaporation fluxes remains overall similar to the one obtained using the previous version of GLEAM, with average correlations against eddy-covariance measurements ranging between 0.78 and 0.81 for the different data sets. These global data sets of terrestrial evaporation and root-zone soil moisture are now openly available at www.GLEAM.eu and may be used for large-scale hydrological applications, climate studies, or research on land-atmosphere feedbacks
Cell Expansion-Dependent Inflammatory and Metabolic Profile of Human Bone Marrow Mesenchymal Stem Cells
Stem cell therapy has emerged as a promising new area in regenerative medicine allowing the recovery of viable tissues. Among the many sources of adult stem cells, bone marrow-derived are easy to expand in culture via plastic adherence and their multipotentiality for differentiation make them ideal for clinical applications. Interestingly, several studies have indicated that MSCs expansion in vitro may be limited mainly due to cell aging related to the number of cell divisions in culture. We have determined that MSCs exhibit a progressive decline across successive passages in the expression of stem cell markers, in plasticity and in the inflammatory response, presenting low immunogenicity. We have exposed human MSCs after several passages to TLRs ligands and analyzed their inflammatory response. These cells responded to pro-inflammatory stimuli (i.e., NOS-2 expression) and to anti-inflammatory cytokines (i.e., HO1 and Arg1) until two expansions, rapidly declining upon subculture. Moreover, in the first passages, MSCs were capable to release IL1β, IL6 and IL8, as well as to produce active MMPs allowing them to migrate. Interestingly enough, after two passages, anaerobic glycolysis was enhanced releasing high levels of lactate to the extracellular medium. All these results may have important implications for the safety and efficacy of MSCs-based cell therapies
Quantifying Li-content for compositional tailoring of lithium ferrite ceramics
Owing to their multiple applications, lithium ferrites are relevant materials
for several emerging technologies. For instance, LiFeO2 has been spotted as an
alternative cathode material in Li-ion batteries, while LiFe5O8 is the lowest
damping ferrite, holding promise in the field of spintronics. The Li-content in
lithium ferrites has been shown to greatly affect the physical properties, and
in turn, the performance of functional devices based on these materials.
Despite this, lithium content is rarely accurately quantified, as a result of
the low number of electrons in Li hindering its identification by means of
routine materials characterization methods. In the present work, magnetic
lithium ferrite powders with Li:Fe ratios of 1:1, 1:3 and 1:5 have been
synthesized, successfully obtaining phase-pure materials (LiFeO2 and LiFe5O8),
as well as a controlled mixture of both phases. The powders have been compacted
and subsequently sintered by thermal treatment (Tmax = 1100 {\deg}C) to
fabricate dense pellets which preserve the original Li:Fe ratios. Li-content on
both powders and pellets has been determined by two independent methods: (i)
Rutherford backscattering spectroscopy combined with nuclear reaction analysis
and (ii) Rietveld analysis of powder X-ray diffraction data. With good
agreement between both techniques, it has been confirmed that the Li:Fe ratios
employed in the synthesis are maintained in the sintered ceramics. The same
conclusion is drawn from spatially-resolved confocal Raman microscopy
experiments on regions of a few microns. Field emission scanning electron
microscopy has evidenced the substantial grain growth taking place during the
sintering process - mean particle sizes rise from about 600 nm in the powders
up to 3.8(6) um for dense LiFeO2 and 10(2) um for LiFe5O8 ceramics
Deep SDSS optical spectroscopy of distant halo stars II. Iron, calcium, and magnesium abundances
We analyze a sample of 3,944 low-resolution (R ~ 2000) optical spectra from
the Sloan Digital Sky Survey (SDSS), focusing on stars with effective
temperatures 5800 < Teff < 6300 K, and distances from the Milky Way plane in
excess of 5 kpc, and determine their abundances of Fe, Ca, and Mg. We followed
the same methodology as in the previous paper in this series, deriving
atmospheric parameters by chi2 minimization, but this time we obtained the
abundances of individual elements by fitting their associated spectral lines.
Distances were calculated from absolute magnitudes obtained by a statistical
comparison of our stellar parameters with stellar-evolution models. The
observations reveal a decrease in the abundances of iron, calcium, and
magnesium at large distances from the Galactic center. The median abundances
for the halo stars analyzed are fairly constant up to a Galactocentric distance
r ~ 20 kpc, rapidly decrease between r ~ 20 and r ~ 40 kpc, and flatten out to
significantly lower values at larger distances, consistent with previous
studies. In addition, we examine the [Ca/Fe] and [Mg/Fe] as a function of Fe/H
and Galactocentric distance. Our results show that the most distant parts of
the halo show a steeper variation of the [Ca/Fe] and [Mg/Fe] with iron. We
found that at the range -1.6 < [Fe/H] < -0.4 [Ca/Fe] decreases with distance,
in agreement with earlier results based on local stars. However, the opposite
trend is apparent for [Mg/Fe]. Our conclusion that the outer regions of the
halo are more metal-poor than the inner regions, based on in situ observations
of distant stars, agrees with recent results based on inferences from the
kinematics of more local stars, and with predictions of recent galaxy formation
simulations for galaxies similar to the Milky Way
Application surface of CPT, an advanced DInSAR displacement near Itoiz dam, Navarra, Spain
Itoiz reservoir is located in Navarra, northern Spain, being a newly constructed gravity dam that stores the water from the Irati and the Urrobi rivers. The dam has a total height of 121 m, a total length of 525 m and a maximum water storage volume of 410 hm3. The aim of this work is to study the surface displacement field during the impoundment of the Itoiz water reservoir. Orbital SAR Differential
Interferometry (DInSAR) techniques have been proven to be a useful and powerful tool in tectonic areas for surveying subtle surface deformations over several years related to geodynamic phenomena. An advanced DInSAR observation technique, Coherent Pixel Technique (CPT), has been applied to study the existence of deformation in the dam area in order to obtain mean velocities and time series of
deformation.
We have studied the applicability of this technique to study the surface displacement field during the impoundment of the Itoiz water reservoir. Specifically, we focus on
the analysis of the stability of the left slope of the reservoir.
We have used ERS and ENVISAT descending and ascending images concerning to the 1992-2008 and 2003-2008 periods respectively. We compare the observation results with the displacement induced by water loading obtained using a theoretical model
CompareML: A Novel Approach to Supporting Preliminary Data Analysis Decision Making
There are a large number of machine learning algorithms as well as a wide range of libraries and services that allow one to create predictive models. With machine learning and artificial intelligence playing a major role in dealing with engineering problems, practising engineers often come to the machine learning field so overwhelmed with the multitude of possibilities that they find themselves needing to address difficulties before actually starting on carrying out any work. Datasets have intrinsic properties that make it hard to select the algorithm that is best suited to some specific objective, and the ever-increasing number of providers together make this selection even harder. These were the reasons underlying the design of CompareML, an approach to supporting the evaluation and comparison of machine learning libraries and services without deep machine learning knowledge. CompareML makes it easy to compare the performance of different models by using well-known classification and regression algorithms already made available by some of the most widely used providers. It facilitates the practical application of methods and techniques of artificial intelligence that let a practising engineer decide whether they might be used to resolve hitherto intractable problems. Thus, researchers and engineering practitioners can uncover the potential of their datasets for the inference of new knowledge by selecting the most appropriate machine learning algorithm and determining the provider best suited to their data
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