658 research outputs found
Empleo de isótopos ambientales para discernir la contaminación salina de la cuenca del río Llobregat
La formación geológica salina de la comarca del Bages(Barcelona) y su explotación minera en diferentes puntos de la cuenca del Llobregat, influyen en la salinización de los ríos Cardener y Llobregat. La cuenca potásica catalana presenta dos peculiaridades: la formación salina tiene un afloramiento en Cardona, y en algunas zonas las capas de mineral se encuentran cerca de la superficie pero sin aflorar. La geología del terreno puede influir en la salinidad de las aguas de la cuenca por contacto directo con los materiales salinos. La actividad minera de Cardona (cerrada en 1990), Suria,Balsareny y Sallent, genera en la producción del mineral un residuo salino que se acumula en el exterior de las minas formándose las escombreras salinas o «runams». Sus salessolubles se disuelven con la lluvia, y pueden llegar a las aguas superficiales y aguas subterráneas del entorno. El objetivo de este trabajo es evaluar las aportaciones salinas a la cuenca del río Llobregat, separando las de origen natural y las de procedencia antrópica, utilizando la composición isotópica del azufre y del oxigeno del sulfato disuelto en sus aguas. También se cuantifica el origen natural y antrópico de los cloruros que se aportan
Hybrids Provide More Options for Fine-Tuning Flowering Time Responses of Winter Barley
Crop adaptation requires matching resource availability to plant development. Tight coordination of the plant cycle with prevailing environmental conditions is crucial to maximizing yield. It is expected that winters in temperate areas will become warmer, so the vernalization requirements of current cultivars can be desynchronized with the environment’s vernalizing potential. Therefore, current phenological ideotypes may not be optimum for future climatic conditions. Major genes conferring vernalization sensitivity and phenological responses in barley (Hordeum vulgare L.) are known, but some allelic combinations remain insufficiently evaluated. Furthermore, there is a lack of knowledge about flowering time in a hybrid context. To honor the promise of increased yield potentials, hybrid barley phenology must be studied, and the knowledge deployed in new cultivars. A set of three male and two female barley lines, as well as their six F1 hybrids, were studied in growth chambers, subjected to three vernalization treatments: complete (8 weeks), moderate (4 weeks), and low (2 weeks). Development was recorded up to flowering, and expression of major genes was assayed at key stages. We observed a gradation in responses to vernalization, mostly additive, concentrated in the phase until the initiation of stem elongation, and proportional to the allele constitution and dosage present in VRN-H1. These responses were further modulated by the presence of PPD-H2. The duration of the late reproductive phase presented more dominance toward earliness and was affected by the rich variety of alleles at VRN-H3. Our results provide further opportunities for fine-tuning total and phasal growth duration in hybrid barley, beyond what is currently feasible in inbred cultivars.his research was supported by the contract “Iberia region hybrid barley variety development and understanding effects of adaptation genes in hybrids,” between CSIC and Syngenta (Basel, Switzerland) Crop Protection AG, which included funding for MF-C scholarship
Phylogenenetic approach of the section Bulbocodii D.C. of Narcissus based on cpDNA. A case of taxonomic inflation ?
In this paper, we analyzed the phylogeny of the section Bulbocodii (genus Narcissus; Amarillydaceae) using the matK and
trnL-F fragments of cpDNA in order to review the validity of the recognized taxa. Our results indicate that Narcissus obesus
should be considered a valid species, and that N. blancoi is a distinct taxon. In addition, seven previously recognized species,
N. juressianus, N. subnivalis, N. graellsii, N. conspicuus, N. citrinus, N. nivalis, and N. quintanilhae, should be assigned to an
infraspecific rank under N. bulbocodium, as they are not valid species. In addition, we analyzed the distribution of the three
morphological characters widely used in the systematics of this section and found that their variation does not agree with the
phylogenetic results, rendering these characters limited taxonomical utility. This result suggests that the section Bulbocodii
shows high morphological lability, which can explain the proliferation of nominal speciesinfo:eu-repo/semantics/publishedVersio
Understanding the active sites of boron nitride for CWPO: An experimental and computational approach
Hexagonal boron nitride (h-BN) has been explored as a catalyst for degrading persistent organic pollutants in
wastewater by Catalytic Wet Peroxide Oxidation (CWPO). Herein, the superior activity of the h-BN on the phenol
degradation (model pollutant) compared to other metal-free catalysts, such as carbon-based ones, and the lower
selectivity to CO encourage the potential application of h-BN catalysts in CWPO processes. Through a combined
density functional theory calculations, experimental reactions and catalyst characterization approach, a com-
prehensive study on the reaction mechanism has been conducted. According to this, only defected B atoms in the
h-BN layer, protonated as B-(OH2)+, decompose the hydrogen peroxide into highly reactive hydroxyl radicals.
The radical species diffuse towards inner h-BN regions and react with the phenol adsorbed by π-π interaction on
the h-BN surface. Oxidation by-products cause carbonaceous deposits and progressive deactivation of the h-BN
catalyst that can be directly regenerated by burning off in air.Comunidad de Madrid-S2018/EMT-4341Ministerio de Ciencia e Innovación y Agencia Estatal de Investigación de España, y fondos FEDER de la Unión Europea (MCIU/AEI/FEDER, UE)-RTI2018-095052-B-I00Ministerio de Ciencia e Innovación de España y EU-FEDER-PID2019-106871 GB-I00Junta de Andalucía-FEDER-US-1381410Comunidad de Madrid-PEJD-2018-PRE/AMB-901
Chemical modeling for pH prediction of acidified musts with gypsum and tartaric acid in warm regions
Winemaking of musts acidified with up to 3 g/L of gypsum (CaSO4 2H2O) and tartaric acid, both individually and in combination, as well as a chemical modeling have been carried out to study the behaviour of these compounds as acidifiers. Prior to fermentation gypsum and tartaric acid reduce the pH by 0.12 and 0.17 pH units/g/L, respectively, but while gypsum does not increase the total acidity and reduces buffering power, tartaric acid shows the opposite behaviour. When these compounds were used in combination, the doses of tartaric acid necessary to reach a suitable pH were reduced. Calcium concentrations increase considerably in gypsum-acidified must, although they fell markedly after fermentation over time. Sulfate concentrations also increased, although with doses of 2 g/L they were lower than the maximum permitted level (2.5 g/L). Chemical modeling gave good results and the errors in pH predictions were less than 5% in almost all case
Quantitative proteomic analysis revealed differentially extracellular protein profiles of osteoarthritic and normal mesenchymal stem cells undergoing chondrogenesis
Sparse initial data indentification for parabolic pde and its finite element approximations
We address the problem of inverse source identification for parabolic equations from the optimal control viewpoint employing measures of minimal norm as initial data. We adopt the point of view of approximate controllability so that the target is not required to be achieved exactly but only in an approximate sense. We prove an approximate inversion result and derive a characterization of the optimal initial measures by means of duality and the minimization of a suitable quadratic functional on the solutions of the adjoint system. We prove the sparsity of the optimal initial measures showing that they are supported in sets of null Lebesgue measure. As a consequence, approximate controllability can be achieved efficiently by means of controls that are activated in a finite number of pointwise locations. Moreover, we discuss the finite element numerical approximation of the control problem providing a convergence result of the corresponding optimal measures and states as the discretization parameters tend to zero.The first author was supported by Spanish Ministerio de Economía y Competitividad under project MTM2011-22711. The third author was supported by the Advanced Grant NUMERIWAVES/FP7-246775 of the European Research Council Executive Agency, FA9550-14-1-0214 of the EOARD-AFOSR, FA9550-15-1-0027 of AFOSR, the BERC 2014-2017 program of the Basque Government, the MTM2011-29306 and SEV-2013-0323 Grants of the MINECO, the CIMI-Toulouse Excellence Chair in PDEs, Control and Numerics and a Humboldt Award at the University of Erlangen-Nürnberg
etrological, geochemical (major, trace, and rare earth elements), and U–Pb zircon data of the Tamatán Group, NE Mexico
From samples of the Paleozoic Tamatán Group (Huizachal–Peregrina Anticlinorium, Tamaulipas, Mexico), petrographic (qualitative and modal) and geochemical analyses (major, trace, and rare earth elements) were conducted. The first U–Pb geochronological data on detrital zircons of the Tamatán Group were generated using four samples. The data presented here contains a broad overview of photomicrography, recalculated modal point-count data, raw geochemical data, and simple statistics of selected geochemical parameters. The data presented in this article are interpreted and discussed in the research article titled “Provenance and tectonic setting of the Tamatán Paleozoic sequence, NE Mexico: Implications for the closure of the Rheic Ocean at the northwestern part of Gondwana”publishedVersio
High-Pressure fractionation of tropical fruits with potential antibacterial activity: M. indica L. and B. Guineensis
The great interest in the potential health benefits of tropical fruits is due to their high content of antioxidants
and phytochemicals. Colombia ranks as the second country with the major biodiversity worldwide. B.
guineensis (Arecaceae) is a palm that grows in Colombia and Central America. The purple-black fruits of this
plant are rich in thermal-stable anthocyanins. M. indica L. (Anacardiaceae) is a great source of phenolic
compounds. It has multiple functional properties including antioxidant, antimicrobial, antidiabetic and
anticarcinogenic activities. In this work, high-pressure extraction techniques: supercritical fluid extraction
(SFE) and enhanced solvent extraction (ESE), and two different fractionation techniques: i) cascade
fractionation and ii) sequential fractionation were applied. Fractions were analyzed by means of their phenolic
content, antioxidant activity, and antibacterial activity against different bacterial strains: E. coli, P. mirabilis, S.
Aurerus, S. enteritidis, E. aerogenes and P. aeruginosa. The sequential fractionation of B. guineensis pulp
consisted in three steps: 1) supercritical CO2, 2) CO2 + 50% ethanol, and 3) CO2/EtOH/H2O (50:25:25). A red
fraction rich in phenolic compounds, high antioxidant and antibacterial capacity (inhibition zone ~ 10 mm) was
obtained in the last step. A cascade fractionation of M. indica leaves using CO2 + 50% H2O and three
separators (S1, S2 and S3) was evaluated. Fractions obtained in S1 and S2 presented antioxidant capacity
and antibacterial activity against P. mirabilis, and S2 also against S. Aureus and Salmonella
Application of a Natural Antioxidant from Grape Pomace Extract in the Development of Bioactive Jute Fibers for Food Packaging
There is an increasing demand for the use of new food packaging materials. In this study, natural jute fibers impregnated with a Petit Verdot Red Grape Pomace Extract (RGPE) was proposed as a new active food packaging material. Pressurized Liquid Extraction (PLE) and Enhanced Solvent Extraction (ESE) techniques were employed to obtain the bioactive RGPE. Afterward the supercritical solvent impregnation conditions to obtain RGPE-natural jute fibers were studied, by varying pressure, modifier percentage and dried RGPE mass. PLE technique offered the highest bioactive extract at 20 MPa, 55 degrees C, 1 h residence time using C2H5OH:H2O (1:1 v/v), providing an EC50 of 3.35 +/- 0.25 and antibacterial capacity against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa (MIC of 12.0, 1.5 and 4.0 mg/mL RGPE respectively). The natural jute fibers impregnated with 3 mL of that RGPE (90 mg/mL) at 50 MPa and 55 degrees C generated the most efficient packing material with regards to its food preservation potential
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