Institution
University of Valencia
Education•Valencia, Spain•
About: University of Valencia is a education organization based out in Valencia, Spain. It is known for research contribution in the topics: Population & Context (language use). The organization has 27096 authors who have published 65669 publications receiving 1765689 citations. The organization is also known as: Universitat de València & UV.
Topics: Population, Context (language use), Neutrino, Medicine, Catalysis
Papers published on a yearly basis
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TL;DR: Arsenate proved to be competitive with the highand low-affinity phosphate uptake system and induced transient membrane potential changes of up to 120 mV which were similar to those induced by phosphate and indicated a cotransport mechanism with at least 2H+/H2As04.
Abstract: Interference of arsenate and vanadate with phosphate uptake in Lemna gibba L. was studied by measuring voltage changes and (32P)phosphate uptake. Arsenate proved to be competitive with the highand low-affinity phosphate uptake system. It induced transient membrane potential changes of up to 120 mV which were similar to those induced by phosphate and indicated a cotransport mechanism with at least 2H+/H2As04. The amplitude of the transient arsenate-induced membrane depolarization was strongly influenced by phosphate starvation. A permanent membrane depolarization to the diffusion potential was achieved within 2 to 6 h in P-starved plants. Thus, arsenate is indeed a strongly competitive physiological analogue of phosphate in higher plants. Vanadate was easily transported into L. gibba as concluded from transient Em changes of up to 110 mV. Vanadate interfered only slightly and non-specifically with the two phosphate transport mechanisms. Like phosphate, vanadate uptake seems to be an H+-cotransport mechanism, both with similar optima at pH 6 0. Unlike phosphate uptake, vanadate-linked membrane depolarization was not affected by high intracellular phosphate concentrations. P-starvation did not enhance the weak long-term effect on Em. Hence, vanadate, in contrast to arsenate, is not regarded as a physiological phosphate analogue. The distinct and rapid vanadate-induced and permanent membrane depolarization of Avena sativa, Triticum aestivum and Glycine max leaves was not seen in Lemna nor in leaves of Gossypium hirsutum and Nicotiana tabacum. Plasmalemma-enriched preparations of L. gibba revealed, however, a high vanadate-sensitive ATPase activity (87%). As a possible explanation for these differences it is suggested that the latter plant species have cytosolic vanadate-detoxifying properties, i.e. they can reduce vanadate to vanadyl ions, in contrast to the former group of plant species.
319 citations
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Woods Hole Oceanographic Institution1, University of Las Palmas de Gran Canaria2, Bar-Ilan University3, Aix-Marseille University4, Linnaeus University5, University of Hawaii6, University of Southern California7, San Francisco State University8, National Sun Yat-sen University9, Montana State University10, National Autonomous University of Mexico11, University of Vigo12, Max Planck Society13, University of Tokyo14, University of Valencia15, University of Southern Mississippi16, University of Georgia17, Leibniz Association18, Oregon State University19, University of California, Santa Cruz20, University of Massachusetts Dartmouth21, National Oceanography Centre, Southampton22, Old Dominion University23, Oregon Health & Science University24, National Oceanography Centre25, Plymouth Marine Laboratory26, University of Copenhagen27, Lamont–Doherty Earth Observatory28, University of Texas at Austin29, University of Miami30
TL;DR: This database is limited spatially, lacking large regions of the ocean especially in the Indian Ocean, but can nevertheless be used to study spatial and temporal distributions and variations of marine N2 fixation, to validate geochemical estimates and to parameterize and validate biogeochemical models.
Abstract: . Marine N2 fixing microorganisms, termed diazotrophs, are a key functional group in marine pelagic ecosystems. The biological fixation of dinitrogen (N2) to bioavailable nitrogen provides an important new source of nitrogen for pelagic marine ecosystems and influences primary productivity and organic matter export to the deep ocean. As one of a series of efforts to collect biomass and rates specific to different phytoplankton functional groups, we have constructed a database on diazotrophic organisms in the global pelagic upper ocean by compiling about 12 000 direct field measurements of cyanobacterial diazotroph abundances (based on microscopic cell counts or qPCR assays targeting the nifH genes) and N2 fixation rates. Biomass conversion factors are estimated based on cell sizes to convert abundance data to diazotrophic biomass. The database is limited spatially, lacking large regions of the ocean especially in the Indian Ocean. The data are approximately log-normal distributed, and large variances exist in most sub-databases with non-zero values differing 5 to 8 orders of magnitude. Reporting the geometric mean and the range of one geometric standard error below and above the geometric mean, the pelagic N2 fixation rate in the global ocean is estimated to be 62 (52–73) Tg N yr−1 and the pelagic diazotrophic biomass in the global ocean is estimated to be 2.1 (1.4–3.1) Tg C from cell counts and to 89 (43–150) Tg C from nifH-based abundances. Reporting the arithmetic mean and one standard error instead, these three global estimates are 140 p 9.2 Tg N yr−1, 18 p 1.8 Tg C and 590 p 70 Tg C, respectively. Uncertainties related to biomass conversion factors can change the estimate of geometric mean pelagic diazotrophic biomass in the global ocean by about p70%. It was recently established that the most commonly applied method used to measure N2 fixation has underestimated the true rates. As a result, one can expect that future rate measurements will shift the mean N2 fixation rate upward and may result in significantly higher estimates for the global N2 fixation. The evolving database can nevertheless be used to study spatial and temporal distributions and variations of marine N2 fixation, to validate geochemical estimates and to parameterize and validate biogeochemical models, keeping in mind that future rate measurements may rise in the future. The database is stored in PANGAEA ( doi:10.1594/PANGAEA.774851 ).
319 citations
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TL;DR: In this paper, the molar ratio between CH3NH3Br, PbBr2, a medium-size alkyl-chain ammonium salt, and 1-octadecene was fine-tuned.
Abstract: Highly luminescent and photostable CH3NH3PbBr3 nanoparticles have been prepared by fine-tuning the molar ratio between CH3NH3Br, PbBr2, a medium-size alkyl-chain ammonium salt, and 1-octadecene. The nanoparticles exhibit an excellent photoluminescence quantum yield (ca. 83%) and average recombination lifetime (ca. 600 ns) in toluene dispersion.
318 citations
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University of South Carolina1, CERN2, University of Trieste3, University of Zaragoza4, Lawrence Livermore National Laboratory5, Lawrence Berkeley National Laboratory6, Doğuş University7, University of Haifa8, Technical University of Denmark9, Petersburg Nuclear Physics Institute10, University of Bonn11, University of Hamburg12, Aristotle University of Thessaloniki13, University of Valencia14, Russian Academy of Sciences15, Yukawa Institute for Theoretical Physics16, Technische Universität Darmstadt17, Institut de Ciències de l'Espai18, Japan Atomic Energy Agency19, Heidelberg University20, University of Tokyo21, University of Rijeka22, Kyoto University23, Max Planck Society24, Tokyo Institute of Technology25, Brookhaven National Laboratory26, University of Florida27, University of California, Berkeley28, University of Cape Town29, Fermilab30, University of Patras31
TL;DR: The International Axion Observatory (IAXO) as mentioned in this paper is the most powerful axion helioscope, reaching sensitivity to axion-photon couplings down to a few × 10−12 GeV−1 and thus probing a large fraction of the currently unexplored axion and ALP parameter space.
Abstract: The International Axion Observatory (IAXO) will be a forth generation axion helioscope. As its primary physics goal, IAXO will look for axions or axion-like particles (ALPs) originating in the Sun via the Primakoff conversion of the solar plasma photons. In terms of signal-to-noise ratio, IAXO will be about 4–5 orders of magnitude more sensitive than CAST, currently the most powerful axion helioscope, reaching sensitivity to axion-photon couplings down to a few × 10−12 GeV−1 and thus probing a large fraction of the currently unexplored axion and ALP parameter space. IAXO will also be sensitive to solar axions produced by mechanisms mediated by the axion-electron coupling gae with sensitivity — for the first time — to values of gae not previously excluded by astrophysics. With several other possible physics cases, IAXO has the potential to serve as a multi-purpose facility for generic axion and ALP research in the next decade. In this paper we present the conceptual design of IAXO, which follows the layout of an enhanced axion helioscope, based on a purpose-built 20 m-long 8-coils toroidal superconducting magnet. All the eight 60cm-diameter magnet bores are equipped with focusing x-ray optics, able to focus the signal photons into ~ 0.2 cm2 spots that are imaged by ultra-low-background Micromegas x-ray detectors. The magnet is built into a structure with elevation and azimuth drives that will allow for solar tracking for ~ 12 h each day.
318 citations
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TL;DR: In this paper, a series of nanostructured rods and cubes with different physico-chemical properties have been synthesized, characterized and tested in the total toluene oxidation.
Abstract: This paper reveals the key importance of surface oxygen defects in the oxidation catalytic activity of nanostructured ceria. A series of nanostructured rods and cubes with different physico–chemical properties have been synthesized, characterized and tested in the total toluene oxidation. The variation of the temperature and base concentration during the hydrothermal syntheses of nanostructured ceria leads not only to different ceria morphologies with high shape purity, but also to structures with tuneable surface areas and defect concentrations. Ceria nanorods present a higher surface area and a higher concentration of bulk and surface defects than nanocubes associated with their exposed crystal planes, leading to high oxidation activities. However, for a given morphology, the catalytic activity for toluene oxidation is directly related to the concentration of surface oxygen defects and not the overall concentration of oxygen vacancies as previously believed.
318 citations
Authors
Showing all 27402 results
Name | H-index | Papers | Citations |
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H. S. Chen | 179 | 2401 | 178529 |
Alvaro Pascual-Leone | 165 | 969 | 98251 |
Sabino Matarrese | 155 | 775 | 123278 |
Subir Sarkar | 149 | 1542 | 144614 |
Carlos Escobar | 148 | 1184 | 95346 |
Marco Costa | 146 | 1458 | 105096 |
Carmen García | 139 | 1503 | 96925 |
Javier Cuevas | 138 | 1689 | 103604 |
M. I. Martínez | 134 | 1251 | 79885 |
Marco Aurelio Diaz | 134 | 1015 | 93580 |
Avelino Corma | 134 | 1049 | 89095 |
Kevin Lannon | 133 | 1652 | 95436 |
Marina Cobal | 132 | 1078 | 85437 |
Mogens Dam | 131 | 1109 | 83717 |
Marcel Vos | 131 | 993 | 85194 |