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Search Results: 1 - 10 of 631597 matches for " L. E. M. Palomino "
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Corrosion Performance of Conversion Treatments for Electrogalvanised Steel Sheet  [PDF]
A. R. Di Sarli, C. I. Elsner, L. E. M. Palomino, C. R. Tomachuk
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2019, DOI: 10.4236/jmmce.2019.75022
Abstract: Chromate conversion treatments have been widely used due to their excellent corrosion resistance properties; however, their use is increasingly restricted because of the highly toxic chromic acid solutions required, with consequent effluent disposal and ecological problems. The removal of these toxic chemicals is considered a priority within most of the developed countries. In this work, the corrosion resistance of different alternative pretreatments applied on electrogalvanised steel sheet: 1) Cr(III) and Zr complexes layer, 2) Ce(III) layer, 3) Ce(III)/Ce(IV) double layer, 4) Cr(VI) chromating was investigated, and its results compared with those from the tests performed using bare electrogalvanized steel sheets as a substrate. These samples were exposed to aerated 0.05 mol/L NaCl or 0.1 mol/L Na2SO4 solutions. The electrochemical behavior of samples was studied by electrochemical techniques. For three days of immersion in the solution test, the experimental results have shown that, compared with the Cr(VI) protective properties, the Cr(III) + Zr complex layer presented similar performance. Even though the initial corrosion resistance was offered by the Ce(III) and Ce(VI)/Ce(III) conversion coatings was relatively good, it quickly decreased as a function of the exposure time.
Eficacia y seguridad de analgesia con remifentanilo en el postoperatorio inmediato de cirugía maxilofacial Efficacy and safety of remifentanil analgesia in the immediate postoperative period of maxillofacial surgery
E. Curiel Balsera,I. Macias Guarasa,M.A. Prieto Palomino,J.L. Mu?oz Mu?oz
Medicina Intensiva , 2012,
Análisis de la morbimortalidad materna de las pacientes con preeclampsia grave, eclampsia y síndrome HELLP que ingresan en una Unidad de Cuidados Intensivos gineco-obstétrica
Curiel-Balsera,E.; Prieto-Palomino,M.á.; Mu?oz-Bono,J.; Ruiz de Elvira,M.J.; Galeas,J.L.; Quesada García,G.;
Medicina Intensiva , 2011,
Abstract: objective: to describe the incidence and clinical and epidemiological profile of patients with severe preeclampsia admitted to intensive care. design: a prospective, observational case series. setting: a specific obstetric 8-bed icu belonging to a university hospital with a total of 55 icu beds. patients: a total of 262 patients admitted due to severe preeclampsia, eclampsia or hellp syndrome. intervention: descriptive analysis of the population and complications in the icu and hospital mortality. results: the mean patient age was 30.47±5.7 years, with the following diagnóstico at admission: a total of 78% of the patients with severe preeclampsia, 16% with hellp syndrome, and 6% with eclampsia, occurring in gestational week 31.85±4.45. in turn, 63% of the patients were nulliparous and had a low prevalence of previous diseases. the global complications rate was 14% (9% heart failure, 5% acute renal failure and 2% coagulopathy). maternal mortality was 1.5% (4 patients), and was associated with non-nulliparous status, the presence of complications, and toast > 71mg/dl. conclusions: severe preeclampsia has a low mortality rate (1.5%), though the complications rate is considerable (14%). the condition develops more often in nulliparous women during the third trimester of pregnancy.
Nonlinear Optical Properties of a MMA-Silica Nanohybrid Material Doped with Rhodamine 6G
J. Lima-Gutiérrez,R. Palomino-Merino,M. L. Arroyo Carrasco,E. Rubio-Rosas,V. M. Casta?o
Journal of Nanomaterials , 2013, DOI: 10.1155/2013/374185
Abstract: A novel nanohybrid material based on MMA-Silica has been synthesized with an organic dye dopant (R6G) to tailor the optical properties. This novel material can be used on several devices such as active laser media for an organic solid state laser, OLEDs, or as a characterization media for new organic dye molecules. Thin films were deposited by dip-coating and characterized by absorption and reflection UV-VIS, photoluminescence, SEM, and Z-scan technique to verify their nonlinear behavior. R6G dye dopant has been used to verify that the nanohybrid matrix does not inhibit its optical properties. 1. Introduction There is a need for developing new economical and simple materials suitable for different applications, in particular those related to nonlinear optical behavior, for applications ranging from nanomedicine to nanoelectronics. For instance, when a nonlinear material is doped with an organic dye it can be used as a laser medium for solid-state organic dye lasers. Nowadays solid-state polymeric dye lasers are of interest [1–3]; they can be used in medicine and cosmetology [4–6], optics [7, 8], electronics [9, 10], and other disciplines. New ways to generate laser light have been developed; tunable solid-state lasers can be obtained by the incorporation of guest dyes in solid host materials and this is one of the ideas that motivates this work. So far, several light-emitting solid systems based on the inclusion of laser dyes inside organic and inorganic solid matrix and hybrid and nanohybrid materials have been developed [11]. The use of sol-gel technique [12] allows incorporating dyes in a solid material at the nanoscale; this technique is based on the hydrolysis of a precursor, forming a gel, and in this part of the process a dopant can be added. When solvents are volatilized a nanoporous glass with the inclusion of the dopant is obtained. So this technique is important because it can change optical, mechanical, thermal, and electrical properties of the matrix formed by the precursor by adding different kinds of dopants like powders, liquids, organic and inorganic materials, nanoparticles, and so forth. The dopants chosen depends on the required material properties and the changes on the amount of dopant inside the matrix. For example, it is possible to add an organic dye to have specific optical properties and some polymer to change its mechanical properties, like flexibility, or to protect the organic dye; PMMA (polymethylmethacrylate) decreases organic dyes degradation on solid-state dye lasers. OLEDs [13, 14] are another technology where organic
Rareza, estatus de conservación y sus determinantes ecológicos. Revisión de su aplicación a escala regional
Carrascal, L. M.,Palomino, D.
Graellsia , 2006,
Abstract: This work reviews the relationships among the ecological basis of rarity, threat categories of species and the definition of their conservation status. When applying quantitative criteria to establish threat categories, there are many logical problems dealing with biodiversity conservation, biological problems dealing with the natural history of the species, and methodological problems linked to scientific design and reliability of the data; these limitations are assessed. It is not advisable to determine national or regional categories of threat when depending on speculative data without scientific credibility. This should be particularly worrying if regional rarity is based on purely biogeographical aspects (e.g., populations at the edges of total distribution ranges). Several alternatives are proposed to apply criteria determining the regional threat status. En este trabajo se efectúa una revisión crítica sobre la rareza ecológica, las categorías de amenaza de las especies y la definición de su estatus de conservación. En la aplicación de los criterios cuantitativos para establecer categorías de amenaza existen numerosos problemas lógicos asociados con la conservación de la biodiversidad, biológicos relacionados con la historia natural de las especies y metodológicos vinculados a aspectos de dise o científico y fiabilidad de los datos. No sería recomendable crear categorías que definan el estatus de amenaza a escalas nacional o regional cuando los datos utilizados sean pura especulación. Esto es especialmente preocupante cuando la rareza a escala regional venga motivada por aspectos puramente biogeográficos (e.g., poblaciones en bordes de distribución). Se proponen alternativas para la aplicación de criterios definitorios de estatus de conservación a escala regional (p.e., nacional o comunidades autónomas).
Preferencias de hábitat, densidad y diversidad de las comunidades de aves en Tenerife (Islas Canarias)
L. M. Carrascal,D. Palomino
Animal Biodiversity and Conservation , 2005,
Abstract: Species–specific habitat preferences, density and species richness of bird communities in Teneriffe (Canary Islands).— Bird distribution and abundance are described and analyzed in Teneriffe (Canary Islands). Inter–habitat differences in density, diversity and species richness are shown in table 1. Figure 2 shows the main determinants of bird species richness in Teneriffe, and tables 2 and 3 and figure 3 show the species–specific patterns of spatial variation abundance (more detailed for Anthus berthelotii, Fringilla coelebs canariensis, Fringilla teydea, Parus caeruleus teneriffae, Phylloscopus canariensis, Regulus teneriffae, Serinus canarius and Turdus merula cabrerae). Deeply transformed environments due to human impact (urban habitats, agricultural mosaics, banana plantations) have high bird densities and species richness, even higher than those measured in native, unmodified habitats such as laurel forests or mature pinewoods. Urban environments in Teneriffe are very permeable to native bird fauna, as they have been occupied by many widespread endemic species/subspecies. Many of the endemic, well defined species or subspecies of island birds have high population densities within native, untransformed habitats. Density compensation and niche expansion is not a common phenomenon in the avifauna of Teneriffe. Nevertheless, all species/subspecies broadening the inter–habitat or altitudinal distribution are endemic of the Canary Islands.
Caliope: an operational air quality forecasting system for the Iberian Peninsula, Balearic Islands and Canary Islands – first annual evaluation and ongoing developments
J. M. Baldasano, P. Jiménez-Guerrero, O. Jorba, C. Pérez, E. López, P. Güereca, F. Martín, M. G. Vivanco, I. Palomino, X. Querol, M. Pandolfi, M. J. Sanz,J. J. Diéguez
Advances in Science and Research (ASR) , 2008, DOI: 10.5194/asr-2-89-2008
Abstract: The Caliope project funded by the Spanish Ministry of the Environment establishes an air quality forecasting system for Spain to increase the knowledge on transport and dynamics of pollutants in Spain, to assure the accomplishment of legislation and to inform the population about the levels of pollutants, topics in which the European Commission has shown a great concern. The present contribution describes the first quantitative verification study performed so far with two chemistry transport models (CMAQ and CHIMERE) for a reference year (2004) at medium spatial resolution (around 20×20 km for the Iberian Peninsula). Both models perform similarly in the case of ground-level ozone. The mean normalised gross error MNGE remains below 15–20% during summertime, when ozone episodes occur, outlining the good skills of the system concerning the forecasting of air quality in Spain. Furthermore, the ongoing developments of the system towards high resolution modelling (4×4 km for Spain, 12×12 km for Europe, 1 h temporal resolution) and the integration with observations within the Caliope umbrella are described.
Fundamentos ecológicos y biogeográficos de la rareza de la avifauna madrile a: Una propuesta de modificación del catálogo regional de especies amenazadas
Carrascal, L. M.,Palomino, D.,Seoane, J.
Graellsia , 2006,
Abstract: The conservation status of bird species of Comunidad de Madrid is analysed using the ecological breadth of the species, the distribution area, their habitat preferences, and maximum ecological densities in the region. The species which are less widely distributed in Madrid are characterized by their low maximum ecological densities, narrow habitat breadths, and limited distribution in the Iberian peninsular. Another component defining regional rarity shows that large-sized species tend to reach lower densities than small-sized birds. These two gradients of ecological rarity are closely associated with the current categories of threat status in Madrid, and allow the proposal and justification of possible modifications of the regional catalogue for 11 species. Se analiza el estatus de conservación de todas las Aves de la Comunidad de Madrid utilizando parámetros ecológicos asociados con la valencia ecológica de las especies, la extensión de su área de distribución, sus preferencias de hábitat y las densidades máximas ecológicas en la región. Las especies menos ampliamente distribuidas en la C.A. de Madrid se caracterizan por sus bajas densidades ecológicas máximas, y por ocupar menor variedad de hábitats y tienen una distribución muy restringida a escala peninsular. Otra componente de la rareza regional se relaciona directamente con la talla corporal, de manera que las especies de mayor tama o tienden a alcanzar menores densidades que las especies más peque as. Estos dos gradientes de rareza ecológica se asocian estrechamente con las actuales categorías oficiales de amenaza de las aves de Madrid, y permiten proponer y justificar posibles modificaciones al Catálogo regional para 11 especies (Cuchara Común – ‘De Interés Especial’; Calamón Común – ‘De Interés Especial’; Alcaraván Común – ‘Sensible a la Alteración de su Hábitat’; Paloma Zurita – ‘De Interés Especial’; Torcecuello Euroasiático – ‘Sensible a la Alteración de su Hábitat’; Calandria – descatalogarla; Mirlo Acuático - ‘Sensible a la Alteración de su Hábitat’; Colirrojo Real - ‘Sensible a la Alteración de su Hábitat’ o ‘Vulnerable’; Papamoscas Gris - ‘De Interés Especial’; Alcaudón Real Meridional – descatalogarla; Picogordo – ‘De Interés Especial’).
Patrones de distribución, abundancia y riqueza de especies de la avifauna terrestre de la isla de La Palma (islas Canarias)
Carrascal, L. M.,Palomino, D.,Polo, V.
Graellsia , 2008,
Abstract: We estimate the population size and density, habitat preferences, habitat breadth and probable population trends in the last 25-15 years of the diurnal terrestrial bird species breeding in La Palma island (Canary islands). Data were obtained in a large extensive census program carried out during the 2007 nesting period using line transects that allowed detectability estimations. We also explored patterns of species richness both at inter-habitat and local scale. Local species richness (species per 0.5 km transects) showed an important geographical component, increasing from south to north, from west to east, and reaching maximum values at altitudes around 600-1,000 m a.s.l. It was also positively related to vegetation development (specially in the herbaceous and shrub layer), and negatively associated with urbanization and agriculture. Total bird density reached the highest figures in the ‘monteverde’ (laurel and heath forests ca. 650 aves/km2), and in the transition pinewoods-laurel forests (509 aves/km2), while the lowest figures were recorded in high altitude shrublands (153 aves/km2) and recent lava fields (58 aves/km2). The bird species with lower population sizes are Falco [peregrinus] pelegrinoides, Burhinus oedicnemus distinctus, Upupa epops, Carduelis carduelis, Miliaria calandra and Petronia petronia, while the last five species have undergone more negative population trends in the last 15-25 years. Se estiman los niveles poblacionales, las densidades ecológicas, los principales patrones de preferencia de hábitat, las posibles tendencias demográficas habidas en los últimos 25 y 15 a os, y el estatus de conservación actual de las especies de aves terrestres diurnas reproductoras en la isla de La Palma. Los datos fueron obtenidos durante el periodo reproductor de 2007, utilizando transectos lineales. En total se efectuaron 437 transectos de 0,5 km repartidos por toda la isla atendiendo a sus formaciones ambientales, situación altitudinal, y posición geográfica. Mediante curvas acumuladas del número de especies se explora la variación en la riqueza de especies. El ambiente con menor biodiversidad aviar es, con diferencia, el matorral altimontano. Por el contrario, los medios con mayor riqueza de especies son las medianías dedicadas a la agricultura y con casas dispersas. La variación local de la riqueza de aves (especies por transecto de 0,5 km) en la isla de La Palma tiene una importante componente geográfica (aumento del sur al norte y del oeste al este, con valores máximos a altitudes medias), asociándose además con el desarrollo de la vegetac
Bias in density estimations using strip transects in dry open-country environments in the Canary Islands
L. M. Carrascal,J. Seoane,D. Palomino
Animal Biodiversity and Conservation , 2008,
Abstract: We studied bias in density estimations derived from strip transects in dry open-country in the Canary Islands. We also present some critical remarks on García-del-Rey's (2005) paper regarding strip transects and the validity of comparisons based on population densities of birds in scrublands on Tenerife island using two different methods: territory mapping and strip transect sampling. Although strip transects with census belts of 25 m do not account for detectability, this method only slightly undervalues true density estimates, and allowed to detect more than 85% of birds present in poorly vegetated environments in the Canary Islands. Previously published works on distribution and abundance of terrestrial birds in the Canary Islands using the strip transect sampling with belts of 25 m on both sides of the observer, thus provide reliable information that only slightly underestimates true densities.
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