Institution
University of Seville
Education•Seville, Andalucía, Spain•
About: University of Seville is a education organization based out in Seville, Andalucía, Spain. It is known for research contribution in the topics: Population & Context (language use). The organization has 20098 authors who have published 47317 publications receiving 947007 citations. The organization is also known as: Universidad de Sevilla.
Topics: Population, Context (language use), Model predictive control, Nonlinear system, Control theory
Papers published on a yearly basis
Papers
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TL;DR: The Kjeldahl method was introduced in 1883 and consists of three main steps: sample digestion, distillation, and ammonia determination (titration being the primary method) as discussed by the authors.
Abstract: The Kjeldahl method was introduced in 1883 and consists of three main steps: sample digestion, distillation, and ammonia determination (titration being the primary method). The Kjeldahl method uses sulfuric acid, a variety of catalysts, and salts to convert organically bound nitrogen in samples to ammonium with its subsequent measurement (Saez-Plaza et al., 2013). Today, this method is universally accepted and used in tens of thousands of laboratories throughout the world for nitrogen analysis in a wide variety of materials, such as foods, beverages, agricultural products, environmental samples, chemicals, biochemicals, and pharmaceuticals. However, successful analysis requires proper sampling and sample handling, which depend on the type of material. The Kjeldahl method has been validated and standardized for total (crude) protein estimation for a wide variety of food matrices, indirectly determined by their nitrogen content, and is the reference method adopted by many international organizations. The Kj...
208 citations
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TL;DR: In this article, Rice husk and sugarcane bagasse were chemically impregnated with ZnCl 2 and carbonized at 700°C in a large-scale rotary furnace.
208 citations
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TL;DR: In vitro studies demonstrate that 1 nM melatonin, which approximates the physiological concentration of the hormone at night, significantly inhibited NOS activity, and results show that calmodulin may be involved in this process since its presence in the incubation medium prevents the inhibitory effect of melatonin on Nos activity.
Abstract: In this report, rat hypothalamic nitric oxide synthase (NOS) activity is shown to be partially inhibited by physiological concentrations of the pineal hormone melatonin. In vitro studies demonstrate that 1 nM melatonin, which approximates the physiological concentration of the hormone at night, significantly inhibited NOS activity. In vivo studies show that administering melatonin or collecting the hypothalamus from animals at night, when endogenous melatonin levels are elevated, results in a significant decrease of NOS activity. Results also show that calmodulin may be involved in this process since its presence in the incubation medium prevents the inhibitory effect of melatonin on NOS activity.
207 citations
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TL;DR: It is demonstrated that the virulence of the ATCC 19606T strain depends on the expression of a fully active acinetobactin-mediated system, and Interestingly, the three models also showed that impairment of BasD production results in an intermediate virulence phenotype compared to those of the parental strain and the BauA mutant.
Abstract: Acinetobacter baumannii, which causes serious infections in immunocompromised patients, expresses high-affinity iron acquisition functions needed for growth under iron-limiting laboratory conditions. In this study, we determined that the initial interaction of the ATCC 19606T type strain with A549 human alveolar epithelial cells is independent of the production of BasD and BauA, proteins needed for acinetobactin biosynthesis and transport, respectively. In contrast, these proteins are required for this strain to persist within epithelial cells and cause their apoptotic death. Infection assays using Galleria mellonella larvae showed that impairment of acinetobactin biosynthesis and transport functions significantly reduces the ability of ATCC 19606T cells to persist and kill this host, a defect that was corrected by adding inorganic iron to the inocula. The results obtained with these ex vivo and in vivo approaches were validated using a mouse sepsis model, which showed that expression of the acinetobactin-mediated iron acquisition system is critical for ATCC 19606T to establish an infection and kill this vertebrate host. These observations demonstrate that the virulence of the ATCC 19606T strain depends on the expression of a fully active acinetobactin-mediated system. Interestingly, the three models also showed that impairment of BasD production results in an intermediate virulence phenotype compared to those of the parental strain and the BauA mutant. This observation suggests that acinetobactin intermediates or precursors play a virulence role, although their contribution to iron acquisition is less relevant than that of mature acinetobactin.
207 citations
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TL;DR: In this article, the authors use simple concepts from the theory of frequency-selective surfaces, waveguides, and transmission lines to explain extraordinary transmission for both thin and thick periodically perforated perfect conductor screens.
Abstract: Extraordinary optical transmission of light or electromagnetic waves through metal plates periodically perforated with subwavelength holes has been exhaustively analyzed in the last ten years. The study of this phenomenon has attracted the attention of many scientists working in the fields of optics and condensed matter physics. This confluence of scientists has given rise to different theories, some of them controversial. The first theoretical explanation was based on the excitation of surface plasmons along the metal-air interfaces. However, since periodically perforated dielectric (and perfect conductor) slabs also exhibit extraordinary transmission, diffraction by a periodic array of scatterers was later considered as the underlying physical phenomenon. From a microwave engineering point of view, periodic structures exhibiting extraordinary optical transmission are very closely related to frequency-selective surfaces. In this paper, we use simple concepts from the theory of frequency-selective surfaces, waveguides, and transmission lines to explain extraordinary transmission for both thin and thick periodically perforated perfect conductor screens. It will be shown that a simple transmission-line equivalent circuit satisfactorily accounts for extraordinary transmission, explaining all of the details of the observed transmission spectra, and easily gives predictions on many features of the phenomenon. Although the equivalent circuit is developed for perfect conductor screens, its extension to dielectric perforated slabs and/or penetrable conductors at optical frequencies is almost straightforward. Our circuit model also predicts extraordinary transmission in nonperiodic systems for which this phenomenon has not yet been reported.
207 citations
Authors
Showing all 20465 results
Name | H-index | Papers | Citations |
---|---|---|---|
Russel J. Reiter | 169 | 1646 | 121010 |
Aaron Dominguez | 147 | 1968 | 113224 |
Jose M. Ordovas | 123 | 1024 | 70978 |
Detlef Lohse | 104 | 1075 | 42787 |
Miroslav Krstic | 95 | 955 | 42886 |
María Vallet-Regí | 95 | 711 | 41641 |
John S. Sperry | 93 | 160 | 35602 |
Jose Rodriguez | 93 | 803 | 58176 |
Shun-ichi Amari | 90 | 495 | 40383 |
Michael Ortiz | 87 | 467 | 31582 |
Bruce J. Paster | 84 | 261 | 28661 |
Floyd E. Dewhirst | 81 | 229 | 42613 |
Joan Montaner | 80 | 489 | 22413 |
Francisco B. Ortega | 79 | 503 | 26069 |
Luis Paz-Ares | 77 | 592 | 31496 |