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1.
Rev. clín. esp. (Ed. impr.) ; 224(4): 225-232, Abr. 2024. ilus
Artículo en Español | IBECS | ID: ibc-232257

RESUMEN

La anemia perioperatoria constituye un factor independiente de riesgo de morbimortalidad posoperatoria. Sin embargo, persisten barreras conceptuales, logísticas y administrativas que dificultan la implementación generalizada de protocolos para su manejo. El coordinador del proyecto convocó a un grupo multidisciplinar de ocho profesionales para elaborar un documento de consenso sobre el manejo de la anemia perioperatoria, con base a en serie puntos claves (PCs) relativos a su prevalencia, consecuencias, diagnóstico y tratamiento. Estos PCs fueron evaluados utilizando una escala Likert de 5 puntos, desde «totalmente en desacuerdo [1]» a «totalmente de acuerdo [5]». Cada PC se consideró consensuado si recibía una puntuación de 4 o 5 por al menos siete participantes (> 75%). A partir de los 36 PCs consensuados, se construyeron algoritmos diagnóstico-terapéuticos que pueden facilitar la implementación de programas de identificación precoz y manejo adecuado de la anemia perioperatoria, adaptados a las características de las instituciones hospitalarias de nuestro país.(AU)


Perioperative anemia is an independent risk factor for postoperative morbidity and mortality. However, conceptual, logistical and administrative barriers persist that hinder the widespread implementation of protocols for their management. The project coordinator convened a multidisciplinary group of 9 experienced professionals to develop perioperative anemia management algorithms, based on a series of key points (KPs) related to its prevalence, consequences, diagnosis and treatment. These KPs were assessed using a 5-point Likert scale, from “strongly disagree [1]” to “strongly agree [5]”. For each KP, consensus was reached when receiving a score of 4 or 5 from at least 7 participants (>75%). Based on the 36 KPs agreed upon, diagnostic-therapeutic algorithms were developed that we believe can facilitate the implementation of programs for early identification and adequate management of perioperative anemia, adapted to the characteristics of the different institutions in our country.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Anemia/complicaciones , Indicadores de Morbimortalidad , Cuidados Posoperatorios , Anemia/diagnóstico , Anemia/terapia , España , Cuidados Preoperatorios , Periodo Preoperatorio , Factores de Riesgo , Consenso
2.
Rev Clin Esp (Barc) ; 224(4): 225-232, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38423382

RESUMEN

Perioperative anemia is an independent risk factor for postoperative morbidity and mortality. However, conceptual, logistical and administrative barriers persist that hinder the widespread implementation of protocols for their management. The project coordinator convened a multidisciplinary group of 8 experienced professionals to develop perioperative anemia management algorithms, based on a series of key points (KPs) related to its prevalence, consequences, diagnosis and treatment. These KPs were assessed using a 5-point Likert scale, from "strongly disagree [1]" to "strongly agree [5]". For each KP, consensus was reached when receiving a score of 4 or 5 from at least 7 participants (>75%). Based on the 36 KPs agreed upon, diagnostic-therapeutic algorithms were developed that we believe can facilitate the implementation of programs for early identification and adequate management of perioperative anemia, adapted to the characteristics of the different institutions in our country.


Asunto(s)
Anemia , Hierro , Humanos , Hierro/uso terapéutico , Consenso , España , Anemia/diagnóstico , Anemia/epidemiología , Anemia/terapia , Factores de Riesgo
7.
Phys Chem Chem Phys ; 22(20): 11362-11373, 2020 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-32373792

RESUMEN

Considering ice-premelting on a quartz rock surface (i.e. silica) we calculate the Lifshitz excess pressures in a four layer system with rock-ice-water-air. Our calculations give excess pressures across (1) ice layer, (2) water layer, and (3) ice-water interface for different ice and water layer thicknesses. We analyse equilibrium conditions where the different excess pressures take zero value, stabilized in part by repulsive Lifshitz interactions. In contrast to previous investigations which considered varying thickness of only one layer (ice or water), here we present theory allowing for simultaneous variation of both layer thicknesses. For a given total thickness of ice and water, this allows multiple alternative equilibrium solutions. Consequently the final state of a system will depend on initial conditions and may explain variation in experimental measurements of the thicknesses of water and ice layers.

8.
Langmuir ; 35(12): 4218-4223, 2019 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-30821464

RESUMEN

Gas bubbles in a water-filled cavity move upward because of buoyancy. Near the roof, additional forces come into play, such as Lifshitz, double layer, and hydrodynamic forces. Below uncharged metallic surfaces, repulsive Lifshitz forces combined with buoyancy forces provide a way to trap micrometer-sized bubbles. We demonstrate how bubbles of this size can be stably trapped at experimentally accessible distances, the distances being tunable with the surface material. By contrast, large bubbles (≥100 µm) are usually pushed toward the roof by buoyancy forces and adhere to the surface. Gas bubbles with radii ranging from 1 to 10 µm can be trapped at equilibrium distances from 190 to 35 nm. As a model for rock, sand grains, and biosurfaces, we consider dielectric materials such as silica and polystyrene, whereas aluminium, gold, and silver are the examples of metal surfaces. Finally, we demonstrate that the presence of surface charges further strengthens the trapping by inducing ion adsorption forces.

9.
ACS Energy Lett ; 1(1): 323-331, 2016 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-28066822

RESUMEN

In this Perspective we discuss the implications of employing metal particles of different shape, size, and composition as absorption enhancers in methylammonium lead iodide perovskite solar cells, with the aim of establishing some guidelines for the future development of plasmonic resonance-based photovoltaic devices. Hybrid perovskites present an extraordinarily high absorption coefficient which, as we show here, makes it difficult to extrapolate concepts and designs that are applied to other solution-processed photovoltaic materials. In addition, the variability of the optical constants attained from perovskite films of seemingly similar composition further complicates the analysis. We demonstrate that, by means of rigorous design, it is possible to provide a realistic prediction of the magnitude of the absorption enhancement that can be reached for perovskite films embedding metal particles. On the basis of this, we foresee that localized surface plasmon effects will provide a means to attain highly efficient perovskite solar cells using films that are thinner than those usually employed, hence facilitating collection of photocarriers and significantly reducing the amount of potentially toxic lead present in the device.

10.
Opt Express ; 23(24): A1642-50, 2015 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-26698810

RESUMEN

The present work proposes the use of a TiO2 electrode coupled to a one-dimensional photonic crystal (1DPC), all formed by the sequential deposition of nanocolumnar thin films by physical vapor oblique angle deposition (PV-OAD), to enhance the optical and electrical performance of DSCs while transparency is preserved. We demonstrate that this approach allows building an architecture combining a non-dispersive 3 µm of TiO2 electrode and 1 µm TiO2-SiO2 1DPC, both columnar, in a single-step process. The incorporation of the photonic structure is responsible for a rise of 30% in photovoltaic efficiency, as compared with a transparent cell with a single TiO2 electrode. Detailed analysis of the spectral dependence of the photocurrent demonstrates that the 1DPC improves light harvesting efficiency by both back reflection and optical cavity modes confinement within the TiO2 films, thus increasing the overall performance of the cell.

11.
J Phys Chem C Nanomater Interfaces ; 119(32): 18635-18640, 2015 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-26500712

RESUMEN

We report on the numerical analysis of solar absorption enhancement in organic-inorganic halide perovskite films embedding plasmonic gold nanoparticles. The effect of particle size and concentration is analyzed in realistic systems in which random particle location within the perovskite film and the eventual formation of dimers are also taken into account. We find a maximum integrated solar absorption enhancement of ∼10% in perovskite films of 200 nm thickness and ∼6% in 300 nm films, with spheres of radii 60 and 90 nm, respectively, in volume concentrations of around 10% in both cases. We show that the presence of dimers boosts the absorption enhancement up to ∼12% in the thinnest films considered. Absorption reinforcement arises from a double contribution of plasmonic near-field and scattering effects, whose respective weight can be discriminated and evaluated from the simulations.

12.
J Phys Chem Lett ; 6(12): 2200-5, 2015 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-26266592

RESUMEN

The photophysical properties of films of organic-inorganic lead halide perovskites under different ambient conditions are herein reported. We demonstrate that their luminescent properties are determined by the interplay between photoinduced activation and darkening processes, which strongly depend on the atmosphere surrounding the samples. We have isolated oxygen and moisture as the key elements in each process, activation and darkening, both of which involve the interaction with photogenerated carriers. These findings show that environmental factors play a key role in the performance of lead halide perovskites as efficient luminescent materials.

13.
J Am Chem Soc ; 135(21): 7803-6, 2013 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-23651222

RESUMEN

Herein we show experimental evidence of resonant photocurrent generation in dye-sensitized periodically nanostructured photoconductors, which is achieved by spectral matching of the sensitizer absorption band to different types of localized photon modes present in either periodic or broken symmetry structures. Results are explained in terms of the calculated spatial distribution of the electric field intensity within the configurations under analysis.

14.
Langmuir ; 25(22): 12860-4, 2009 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-19831378

RESUMEN

Herein, we present a detailed analysis of the structure of artificial opal films. We demonstrate that, rather than the generally assumed face centered cubic lattice of spheres, opal films are better approximated by rhombohedral assemblies of distorted colloids. Detailed analysis of the optical response in a very wide spectral range (0.4 < or = a/lambda < or = 2, where a is the conventional lattice constant), as well as at perpendicular and off-normal directions, unambiguously shows that the interparticle distance coincides very approximately with the expected diameter only along directions contained in the same close-packed plane but differs significantly in directions oblique to the [111] one. A full description of the real and reciprocal lattices of actual opal films is provided, as well as of the photonic band structure of the proposed arrangement. The implications of this distortion in the optical response of the lattice are discussed.

15.
Langmuir ; 24(16): 9135-9, 2008 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-18630935

RESUMEN

Herein we report an analysis of the variation of the optical properties of different nanoparticle-based one-dimensional photonic crystal architectures versus changes in the ambient vapor pressure. Gradual shift of the optical response provides us with information on the sorption properties of these structures and allow us to measure precise adsorption isotherms of these porous multilayers. The potential of nanoparticle-based one-dimensional photonic crystals as base materials for optical sensing devices is demonstrated in this way.

16.
Trastor. adict. (Ed. impr.) ; 10(2): 98-103, abr. 2008. tab
Artículo en Es | IBECS | ID: ibc-67107

RESUMEN

Objetivo. El estudio tuvo como objetivoexplorar la presencia del consumo de drogas legalese ilegales en las embarazadas atendidas en los doshospitales públicos de mayor consulta obstétrica deMontevideo (Uruguay).Material y métodos. Para el logro de este objetivose consideró el examen de laboratorio del meconiode los recién nacidos. La determinación del consumode alcohol se realizó por la determinación de losésteres etílicos de ácidos grasos (FAEES). En el restode las drogas se utilizó el método de ELISA.Resultados. Las pruebas sobre meconio indicaronque el consumo en el embarazo fue de 44,0% de alcohol,51,8% de tabaco, 8,3% de anfetaminas, 2,5%de cocaína/pasta base y 2% de marihuana. Informacióncomplementaria fue recolectada por una encuestaa la madre relacionada con los controles médicosdurante el embarazo. Se halló que un 8,9% delas madres no tuvieron control prenatal. Por otraparte, desde el sistema de salud, se encontró que el34% de los médicos que controlaron el embarazoadvirtió a las gestantes sobre los riesgos del hábitode fumar, el 27% lo hizo en relación al consumo dealcohol y un 7% sobre el uso de drogas ilegales.Conclusiones. El estudio pone de manifiesto queel consumo de alcohol, tabaco y drogas es frecuenteentre las mujeres embarazadas de Uruguay, y quese precisan intervenciones especificas en este colectivopara alertar de los riesgos del consumo de sustanciasen el embarazo


Objective. The objective of this studywas to explore legal and illegal drugs in pregnantwomen at two of the main obstetric public hospitalsin Montevideo (Uruguay).Material and methods. To perform this objectivethe exams in the meconium were used. Fatty acidethyl esters (FAEES) were used to determine alcoholconsumption in the mother. For other drugs it wasELISA tests.Results. Meconium tests indicated that alcoholconsumption during pregnancy was 44.0%, tobacco51.8%, 2.5% for cocaine/base paste, 8.3% for amphetaminesand 2% for marihuana. There was more mother information from a survey carried out at medical controls during pregnancy. The results of this said survey was that 8.9% of those mothers did not have any pregnancy control. Also that 34% of the medical doctors that controlled the mothers aware them on the smoking tobacco risks, about alcohol consumption 27% and 7.8% on illegal drugsuse.Conclusions. The present study shows that alcohol,tobacco and illicit drugs are frequently consumedby pregnant women in Uruguay, and urge forthe development of specific actions at this level


Asunto(s)
Humanos , Femenino , Embarazo , Trastornos Relacionados con Sustancias/epidemiología , Utilización de Medicamentos/estadística & datos numéricos , Psicotrópicos/uso terapéutico , Complicaciones del Embarazo/tratamiento farmacológico , Consumo de Bebidas Alcohólicas/epidemiología , Tabaquismo/epidemiología , Factores de Riesgo , Detección de Abuso de Sustancias , Uruguay/epidemiología
17.
Langmuir ; 23(20): 9933-8, 2007 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-17764202

RESUMEN

A theoretical and experimental analysis of the growth dynamics of colloidal crystal films deposited by evaporation induced self-assembly is herein presented. We derive an expression for the film growth velocity from which we obtain an equation that describes the evolution of the forming crystal thickness with time. Its validity is confirmed by comparison to the experimental profiles of a large number of films grown under different conditions. We find that, on top of the already reported linear increase in film width over long distances in the growth direction, periodic variations of the friction force at the meniscus give rise to short-range thickness fluctuations that are the main source of spatial inhomogeneities observed in these lattices. The key parameters that determine the period and the intensity of these fluctuations are identified.

18.
Langmuir ; 21(2): 499-503, 2005 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-15641812

RESUMEN

In this paper, we describe a rapid, accurate, and convenient method for postsynthetically tuning the optical properties of colloidal photonic crystals. High quality photonic crystal films are first synthesized and then coated iteratively with layers of water-soluble polyelectrolytes. The coating process results in nanometer-scale shifts in the photonic stop band, a process which has been monitored by theoretical modeling. The results suggest a fundamentally different, reproducible layering mechanism inside the confined spaces of the colloidal crystal where polyelectrolyte multilayers are less densely packed.

19.
J Phys Chem B ; 109(33): 15968-76, 2005 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-16853026

RESUMEN

The effect of the presence of a photonic crystal on the optical absorption of dye-sensitized titanium oxide solar cells is theoretically investigated herein. Different configurations in which a colloidal crystal can be implemented in such devices are modeled, and their absorptances compared. Experimental results on light-harvesting enhancement recently reported for periodically structured photoelectrodes are satisfactorily explained in terms of the appearance of multiple resonant modes localized in the absorbing layer when this is deposited onto one of the optical lattice surfaces. Longer matter-radiation interaction times for such frequencies result in higher absorption of those modes when compared to standard dye-sensitized solar cells. The effect of the finite size and the different characteristics of the photonic crystal on the optical absorption amplification effect is also discussed, new perspectives for colloidal-crystal-based photovoltaics being proposed.

20.
Cuad. Hosp. Clín ; 47(1): 80-86, 2001. tab
Artículo en Español | LILACS | ID: lil-312160

RESUMEN

Pregunta de investigación. ¿Cuáles son las características bio-celularesde las leucemias agudas en Bolivia, y presentará diferencias comparando con otros países?. Objetivos: 1. Determinar las caracteristicas bio-celulares de las leucemias agudas en Bolivia. 2. Comparar la frecuencia y distribución de las características bio-celualres de las leucemias agudas en otros países. Diseño: Descriptivo, corte transversal.Lugar: Unidad de Biología Molecular Paolo Belli, Instituto de Genética, Facultad de Medicina. UMSA. La Paz, Bolivia. Poblacióo: 100 Pacientes con leucemias agudas, 48 niños y 52 adultos provenientes de diferentes Centros Hospitalarios del país. Métodos: Las muestras de sangre periférica y médula ósea fueron estudiados con lossiguientes métodos de análissi: a)Estudio morfológico con tinción May Grunwald-Giemsa, B9 Estudio citoquímico con Mieloperoxidasa y Alfa Nalfta Naftil Butirato Esterasa c) Estudio Inmunocitoquímico utilizando anticuerpos monoclonales. Los resultados fueron analizados según el paquete estadísitco EPIDAR versión 2.0. Resultados: De los 100 casos de leucemias agudas, 48 fueron pediatricos (LLA 83.3 porciento y LMA 16.7 porciento); 95 porciento fueron LLA-B y 5 porciento LLA-T; por ora parte las LMA se distribuyeron como sigue: 12.5 porciento MO, 37.5 M1, 37.5 porciento M2 y 12.5 porciento M4. De los 52 adultos (LLA 61.5 porciento y LMA 38.5 porciento); 87.5 porciento fueron LLA-B y 12.5 porciento LLA-T. La LMA se distribuyeron de la siguiente manera: 10 porciento MO, 35 porciento M1, 15 porciento M2, 35 porciento M3 y 5 porciento M5. Conclusiones: Los valores porcentuales obtenidos en el presente estudio reflejan un patrón característico para nuestra población y confirman su diversidad epidemiológica de las leucemias agudas en comparación con otras regiones.


Asunto(s)
Humanos , Masculino , Femenino , Leucemia , Bolivia
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