291 research outputs found
Influencia de nuevas técnicas de desinfección de suelos sobre la precocidad y productividad del fresón ecológico.
Una pérdida del equilibrio del suelo puede presentar peligrosidad para el cultivo por la
presencia de hongos patógenos, nemátodos parásitos, ácaros,…En agricultura
ecológica se hace necesaria una rotación de cultivos para controlar la presión de los
patógenos, que puede verse complementado con los tratamientos de biofumigación y
solarización. Con este trabajo se pretende estudiar la influencia de nuevas técnicas de
desinfección de suelos, como son la biofumigación y la solarización, en la precocidad
y productividad en el cultivo ecológico de fresón. El ensayo se desarrolló durante las
campañas 2003/04 y 2004/05 en una explotación comercial ecológica certificada de
Almonte (Huelva). Para ello se diseñó un experimento en bloques al azar, con tres
repeticiones en el que se dispusieron tres tratamientos: control (C), biofumigación (BF)
y biofumigación+solarización (BF+S). Durante la campaña 2003-04 los resultados
mostraron diferencias significativas en la producción de fresón de primera categoría
comercial entre los tratamientos biofumigados y el tratamiento control, alcanzándose
valores máximos de producción de 623,5 g planta-1 en el tratamiento biofumigación. La
precocidad durante la primera campaña mostró diferencias significativas entre el
tratamiento biofumigación+solarización y el tratamiento control. En la campaña
2004/05 la influencia de las heladas sobre el cultivo del fresón pudo ser la causa que
provocó la ausencia de diferencias significativas entre los tratamientos, a pesar de ello
se siguieron obteniendo las mayores producciones con los tratamientos biofumigados
Magnetically propelled chained nanocomposites for biologically relevant media exploration
Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGElongated nanostructures to be remotely and magnetically propelled in biologically relevant media, have gained attention as offering themselves as effective tools or carriers in theragnostics applications. However, the magnetic actuation associated remains challenging due to the lack of mechanical information in the media of interest, taking into account biophysical or biomedical purposes. In this study, we detail the magnetic actuation of magnetically propelled chained nanocomposites considering their dynamics, in which their velocity can be modulated in terms of the viscosity of the medium considered, given a magnetic field gradient. Simpler cases of distilled water, a water/glycerol mixture and a fluid made of cell extracts (imitating the cytosol of cells) of known viscosity are the basis experiments for the study of more complex media inside HeLa cells, murine NIH-3T3 fibroblasts and zebrafish larvae, offering the mechanical information required. The experimental results indicate that the magnetically propelled performance of the chained nanostructures can be precisely controlled in potentially changing scenarios, where drug and heat delivery, magnetic separation, or microfluidic technologies are demanded, using a magnetic field gradient and providing good estimations of the dynamical parameters involved.Xunta de Galicia | Ref. ED481A/322Xunta de Galicia | Ref. IN606A-2018/019Xunta de Galicia | Ref. IN853B 2018/03Ministerio de Economía y Competitividad | Ref. PI16/00496Instituto de Salud Carlos III | Ref. PI19/00349Instituto de Salud Carlos III | Ref. DTS19/00033Agencia Estatal de Investigación | Ref. MAT2016-81955-REDTAgencia Estatal de Investigación | Ref. PID2020-119242-I0
Demagnetization via Nucleation of the Nonequilibrium Metastable Phase in a Model of Disorder
We study both analytically and numerically metastability and nucleation in a
two-dimensional nonequilibrium Ising ferromagnet. Canonical equilibrium is
dynamically impeded by a weak random perturbation which models homogeneous
disorder of undetermined source. We present a simple theoretical description,
in perfect agreement with Monte Carlo simulations, assuming that the decay of
the nonequilibrium metastable state is due, as in equilibrium, to the
competition between the surface and the bulk. This suggests one to accept a
nonequilibrium "free-energy" at a mesoscopic/cluster level, and it ensues a
nonequilibrium "surface tension" with some peculiar low-T behavior. We
illustrate the occurrence of intriguing nonequilibrium phenomena, including:
(i) Noise-enhanced stabilization of nonequilibrium metastable states; (ii)
reentrance of the limit of metastability under strong nonequilibrium
conditions; and (iii) resonant propagation of domain walls. The cooperative
behavior of our system may also be understood in terms of a Langevin equation
with additive and multiplicative noises. We also studied metastability in the
case of open boundaries as it may correspond to a magnetic nanoparticle. We
then observe burst-like relaxation at low T, triggered by the additional
surface randomness, with scale-free avalanches which closely resemble the type
of relaxation reported for many complex systems. We show that this results from
the superposition of many demagnetization events, each with a well- defined
scale which is determined by the curvature of the domain wall at which it
originates. This is an example of (apparent) scale invariance in a
nonequilibrium setting which is not to be associated with any familiar kind of
criticality.Comment: 26 pages, 22 figure
The ALHAMBRA survey: evolution of galaxy spectral segregation
We study the clustering of galaxies as a function of spectral type and
redshift in the range using data from the Advanced Large
Homogeneous Area Medium Band Redshift Astronomical (ALHAMBRA) survey. The data
cover 2.381 deg in 7 fields, after applying a detailed angular selection
mask, with accurate photometric redshifts [] down to
. From this catalog we draw five fixed number density,
redshift-limited bins. We estimate the clustering evolution for two different
spectral populations selected using the ALHAMBRA-based photometric templates:
quiescent and star-forming galaxies. For each sample, we measure the real-space
clustering using the projected correlation function. Our calculations are
performed over the range Mpc, allowing us to find a
steeper trend for Mpc, which is especially clear for
star-forming galaxies. Our analysis also shows a clear early differentiation in
the clustering properties of both populations: star-forming galaxies show
weaker clustering with evolution in the correlation length over the analysed
redshift range, while quiescent galaxies show stronger clustering already at
high redshifts, and no appreciable evolution. We also perform the bias
calculation where similar segregation is found, but now it is among the
quiescent galaxies where a growing evolution with redshift is clearer. These
findings clearly corroborate the well known colour-density relation, confirming
that quiescent galaxies are mainly located in dark matter halos that are more
massive than those typically populated by star-forming galaxies.Comment: 14 pages, 9 figures, accepted by Ap
The ALHAMBRA survey : Estimation of the clustering signal encoded in the cosmic variance
The relative cosmic variance () is a fundamental source of
uncertainty in pencil-beam surveys and, as a particular case of count-in-cell
statistics, can be used to estimate the bias between galaxies and their
underlying dark-matter distribution. Our goal is to test the significance of
the clustering information encoded in the measured in the ALHAMBRA
survey. We measure the cosmic variance of several galaxy populations selected
with band luminosity at as the intrinsic dispersion in
the number density distribution derived from the 48 ALHAMBRA subfields. We
compare the observational with the cosmic variance of the dark
matter expected from the theory, . This provides an
estimation of the galaxy bias . The galaxy bias from the cosmic variance is
in excellent agreement with the bias estimated by two-point correlation
function analysis in ALHAMBRA. This holds for different redshift bins, for red
and blue subsamples, and for several band luminosity selections. We find
that increases with the band luminosity and the redshift, as expected
from previous work. Moreover, red galaxies have a larger bias than blue
galaxies, with a relative bias of . Our results
demonstrate that the cosmic variance measured in ALHAMBRA is due to the
clustering of galaxies and can be used to characterise the affecting
pencil-beam surveys. In addition, it can also be used to estimate the galaxy
bias from a method independent of correlation functions.Comment: Astronomy and Astrophysics, in press. 9 pages, 4 figures, 3 table
Saturated fatty acid-enriched small extracellular vesicles mediate a crosstalk inducing liver inflammation and hepatocyte insulin resistance
[Background & Aims]: Lipotoxicity triggers non-alcoholic fatty liver disease (NAFLD) progression owing to the accumulation of toxic lipids in hepatocytes including saturated fatty acids (SFAs), which activate pro-inflammatory pathways. We investigated the impact of hepatocyte- or circulating-derived small extracellular vesicles (sEV) secreted under NAFLD conditions on liver inflammation and hepatocyte insulin signalling.
[Methods]: sEV released by primary mouse hepatocytes, characterised and analysed by lipidomics, were added to mouse macrophages/Kupffer cells (KC) to monitor internalisation and inflammatory responses. Insulin signalling was analysed in hepatocytes exposed to conditioned media from sEV-loaded macrophages/KC. Mice were i.v. injected sEV to study liver inflammation and insulin signalling. Circulating sEV from mice and humans with NAFLD were used to evaluate macrophage–hepatocyte crosstalk.
[Results]: Numbers of sEV released by hepatocytes increased under NAFLD conditions. Lipotoxic sEV were internalised by macrophages through the endosomal pathway and induced pro-inflammatory responses that were ameliorated by pharmacological inhibition or deletion of Toll-like receptor-4 (TLR4). Hepatocyte insulin signalling was impaired upon treatment with conditioned media from macrophages/KC loaded with lipotoxic sEV. Both hepatocyte-released lipotoxic sEV and the recipient macrophages/KC were enriched in palmitic (C16:0) and stearic (C18:0) SFAs, well-known TLR4 activators. Upon injection, lipotoxic sEV rapidly reached KC, triggering a pro-inflammatory response in the liver monitored by Jun N-terminal kinase (JNK) phosphorylation, NF-κB nuclear translocation, pro-inflammatory cytokine expression, and infiltration of immune cells into the liver parenchyma. sEV-mediated liver inflammation was attenuated by pharmacological inhibition or deletion of TLR4 in myeloid cells. Macrophage inflammation and subsequent hepatocyte insulin resistance were also induced by circulating sEV from mice and humans with NAFLD.
[Conclusions]: We identified hepatocyte-derived sEV as SFA transporters targeting macrophages/KC and activating a TLR4-mediated pro-inflammatory response enough to induce hepatocyte insulin resistance.This work was supported by grants PID2021-122766OB-I00 (AMV), PID2019-105989RB-I00 (JB), PID2020-113238RB-I00 (LB), PID2019-106581RB-I00 (MAM), PID2020-114148RB-I00 (MI), PID2019-107036RB-I00 (RF), and RD21/0006/0001 (ISCIII) (IL) funded by Ministerio de Ciencia e Innovación/Agencia Estatal de Investigación/10.13039/501100011033 and ERDF ‘A way of making Europe’ by the European Union (MICINN/AEI/FEDER, EU), grant EFSD/Boehringer Ingelheim European Research Programme on ‘Multi-System Challenges in Diabetes’ from the European Foundation for the Study of Diabetes (AMV), P2022/BMD-7227 (Comunidad de Madrid, Spain) (AMV), Fundación Ramón Areces (Spain) (AMV), CIBERdem (AMV and JB), CIBERhed (RF), and CIBERcv (LB) (ISCIII, Spain). LB and AMV belong to the Spanish National Research Council’s (CSIC’s) Cancer Hub. We also acknowledge the Spanish Ministry of Economy and Competitiveness (MINECO) postdoctoral contract IJCI-2015-24758 to IGM and the Spanish Ministry of Education, Culture and Sport (MECD) FPU17/02786 grant to RA
The ALHAMBRA survey : band luminosity function of quiescent and star-forming galaxies at by PDF analysis
Our goal is to study the evolution of the band luminosity function (LF)
since using ALHAMBRA data. We used the photometric redshift and the
band selection magnitude probability distribution functions (PDFs) of those
ALHAMBRA galaxies with 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 and the
evolving Schechter parameters both for quiescent and star-forming galaxies
agree with previous results in the literature. The estimated redshift evolution
of is and , and of is
and . The measured faint-end slopes are and . We find a significant
population of faint quiescent galaxies, modelled by a second Schechter function
with slope . We find a factor decrease in the
luminosity density of star-forming galaxies, and a factor
increase in the of quiescent ones since , confirming the continuous
build-up of the quiescent population with cosmic time. The contribution of the
faint quiescent population to increases from 3% at to 6% at .
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
PREVALENCIA DE INFECCIÓN EN LA HERIDA QUIRÚRGICA EN PACIENTE GINECOLÓGICA A LOS DIEZ Y VEINTE DÍAS DE LA INTERVENCIÓN POR LAPAROTOMÍA Y CON ALTA PRECOZ
Longitudinal study (two observations) in 109 gynecological patients that underwent laparotomy surgery and patient early check out and that had received training for self-care at check out. With the objective of knowing the prevalence of surgical wound infection ten or twenty days after the operation and to identify the impact of education for self-care.
The procedure for information collection consisted of two semistructured interviews, carried out via telephone, where among other questions they were asked about the characteristics of the wound, the person and the place where the cure was received. The prevalence of the infection was found in 10 % of the patients after ten days and in 5 % after twenty days. The relationship between the variable of the infection, person and where curing took place, make us put special emphasis in valuing the conditions of treatment, and the consequences of multi-personal involvement.Estudio longitudinal (2 observaciones) en 109 pacientes ginecológicas intervenidas por laparotomia y con alta precoz y que habian recibido formación para el autocuidado al alta. Con los objetivos de conocer la prevalencia de infección en la hérida quirurgica a los 10 y 20 días de la intervención y de identificar el impacto de la educación para el autocuidado.
El procedimiento de recogida de información consistió en dos entrevistas semiestructuradas, realizadas vía telefónica, donde entre otros aspectos se preguntaba sobre las características de la herida, y la persona y lugar donde se realizaba la cura. La prevalencia de infección se encontró en el 10% a los 10 días y el 5 % a los 20 días. La relación entre la variable signos de infección y persona y lugar de la cura lleva a hacer hincapié en valorar las condiciones en que se realizan la curas y en las consecuencias de la intervención de varias manos en la cura de la herida
Diversity and relationships in key traits for functional and apparent quality in a collection of eggplant: fruit phenolics content, antioxidant activity, polyphenol oxidase activity, and browning
This document is the Accepted Manuscript version of a Published Work that appeared in final form in
Journal of Agricultural and Food Chemistry, copyright © American Chemical Society after peer review and technical editing by the publisher.
To access the final edited and published work seehttp://dx.doi.org/10.1021/jf402429kEggplant (Solanum melongena) varieties with increased levels of phenolics in the fruit present enhanced functional quality, but may display greater fruit flesh browning. We evaluated 18 eggplant accessions for fruit total phenolics content, chlorogenic acid content, DPPH scavenging activity, polyphenol oxidase (PPO) activity, liquid extract browning, and fruit flesh browning. For all the traits we found a high diversity, with differences among accessions of up to 3.36-fold for fruit flesh browning. Variation in total content in phenolics and in chlorogenic acid content accounted only for 18.9% and 6.0% in the variation in fruit flesh browning, and PPO activity was not significantly correlated with fruit flesh browning. Liquid extract browning was highly correlated with chlorogenic acid content (r = 0.852). Principal components analysis (PCA) identified four groups of accessions with different profiles for the traits studied. Results suggest that it is possible to develop new eggplant varieties with improved functional and apparent quality.This project has been funded by Universitat Politecnica de Valencia through the grants SP20120681 and PAID-06-11 Nr. 2082, and by Ministerio de Economia y Competitividad Grant AGL2012-34213 (jointly funded by FEDER).Plazas Ávila, MDLO.; López Gresa, MP.; Vilanova Navarro, S.; Torres Vidal, C.; Hurtado Ricart, M.; Gramazio, P.; Andújar Pérez, I.... (2013). Diversity and relationships in key traits for functional and apparent quality in a collection of eggplant: fruit phenolics content, antioxidant activity, polyphenol oxidase activity, and browning. Journal of Agricultural and Food Chemistry. 61(37):8871-8879. https://doi.org/10.1021/jf402429kS88718879613
Electrochemical Behaviour of Galvanized Steel Embedded in Concrete Exposed to Sand Contaminated with NaCl
This research evaluates the corrosion of reinforced concrete, exposed to marine sand, simulating what happens with the elements of laying of foundations of all concrete structures constructed on coasts of Mexico and the world. In such concrete specimens a steel bar AISI 1018 and Galvanized Steel was embedded as reinforcement, the mixed concrete was of ratio w/c=0.45 (f´c = 350 kg / cm2), according to ACI 211.1, using two type cements CPC 30R and CPC 30R RS. The corrosion rate was evaluated by electrochemical techniques, corrosion potential Ecorr (ASTM C-876-09) and Linear Polarization Resistance (ASTM-G59). These specimens were exposed in a marine sand contaminated with 0, 1, 2 and 3% NaCl, the exposure time was 260 days where, according to the electrochemical results of Ecorr and Icorr, we could determine that the better performance of the specimens was galvanized steel and concrete made with cement CPC 30R RS, this research demonstrated the importance of developing special to elaborated concrete durability in aggressive environment such as is the ground where uproots all reinforced concrete structures
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