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1.
Med Ultrason ; 24(4): 434-450, 2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-35574917

RESUMEN

The history of the European Federation of Societies in Ultrasound in Medicine and Biology (EFSUMB) is closely related to the general history of ultrasound. In the presented paper the physical background and history of technologies including A-mode, Time motion or M-mode, 2D Imaging (B-mode) are summarized. In addition, ultrasound tissue characterization, Doppler ultrasound, 3D and 4D ultrasound, intracavitary and endoscopic ultrasound, interventional ultrasound, ultrasonic therapy, contrast enhanced ultrasound (CEUS) and key developments in echocardiography are discussed.


Asunto(s)
Aniversarios y Eventos Especiales , Ultrasonografía Intervencional , Humanos , Medios de Contraste , Sociedades Médicas , Ultrasonografía/métodos
2.
ACS Appl Mater Interfaces ; 13(51): 61707-61722, 2021 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-34913672

RESUMEN

Energy consumption by air-conditioning is expansive and leads to the emission of millions of tons of CO2 every year. A promising approach to circumvent this problem is the reflection of solar radiation: Rooms that would not heat up by irradiation will not need to be cooled down. Especially, transparent conductive metal oxides exhibit high infrared (IR) reflectivity and are commonly applied as low-emissivity coatings (low-e coatings). Indium tin oxide (ITO) coatings are the state-of-the-art application, though indium is a rare and expensive resource. This work demonstrates that aluminum-doped zinc oxide (AZO) can be a suitable alternative to ITO for IR-reflection applications. AZO synthesized here exhibits better emissivity to be used as roofing membrane coatings for buildings in comparison to commercially available ITO coatings. AZO particles forming the reflective coating are generated via solvothermal synthesis routes and obtain high conductivity and IR reflectivity without the need of any further post-thermal treatment. Different synthesis parameters were studied, and their effects on both conductive and optical properties of the AZO nanoparticles were evaluated. To this end, a series of characterization methods, especially 27Al-nuclear magnetic resonance spectroscopy (27Al-NMR) analysis, have been conducted for a deeper insight into the particles' structure to understand the differences in conductivity and optical properties. The optimized AZO nanoparticles were coated on flexible transparent textile-based roofing membranes and tested as low-e coatings. The membranes demonstrated higher thermal reflectance compared with commercial ITO materials with an emissivity value lowered by 16%.

3.
Dalton Trans ; 46(18): 6039-6048, 2017 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-28426069

RESUMEN

Indium tin oxide (ITO) particle coatings are known for high transparency in the visible, good conductive properties and near-infrared absorption. These properties depend on ITO particle's stoichiometric composition, defects and size. Here we present a method to gradually change ITO particle's optical properties by a simple and controlled laser irradiation process. The defined irradiation process and controlled energy dose input allows one to engineer the absorption and transmission of coatings made from these particles. We investigate the role of the surrounding solvent, influence of laser fluence and the specific energy dose targeting modification of the ITO particle's morphology and chemistry by stepwise laser irradiation in a free liquid jet. TEM, SEM, EDX, XPS, XRD and Raman are used to elucidate the structural, morphological and chemical changes of the laser-induced ITO particles. On the basis of these results the observed modification of the optical properties is tentatively attributed to chemical changes, e.g. laser-induced defects or partial reduction.

4.
Oncologist ; 10(3): 225-37, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15793226

RESUMEN

This prospective, open-label, multicenter study was undertaken to determine the safety and efficacy of epoetin alfa in increasing hemoglobin levels and improving quality of life (QOL), specifically fatigue, in cancer patients receiving chemotherapy with or without radiotherapy (n=702). Epoetin alfa, 10,000 IU three times a week s.c. for 8-18 weeks, increased the mean hemoglobin level relative to baseline (1.0 +/- 1.5 g/dl by week 4 and > or =1.7 g/dl from week 10 through the end of the trial), with 63.4% of patients experiencing > or =2 g/dl increases in hemoglobin above baseline at some time during the study. Fatigue is an important component of QOL. Physicians, nurses, and patients independently assessed patient fatigue level on a linear-analogue scale. Although all three groups reported improvements in patient fatigue over the course of the study (p <.0001), the magnitude of fatigue ratings and their relationship to tumor response and to hemoglobin level varied by group. Overall, epoetin alfa was well tolerated and effective in improving hemoglobin levels and decreasing fatigue in patients undergoing chemotherapy.


Asunto(s)
Anemia/inducido químicamente , Anemia/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Eritropoyetina/farmacología , Eritropoyetina/uso terapéutico , Hematínicos/farmacología , Hematínicos/uso terapéutico , Hemoglobinas , Calidad de Vida , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Epoetina alfa , Fatiga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Estudios Prospectivos , Proteínas Recombinantes , Resultado del Tratamiento
5.
Environ Sci Technol ; 38(13): 3760-7, 2004 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-15296330

RESUMEN

Fly ash is commonly deposited in special landfills as it contains toxic concentrations of heavy metals, such as Zn, Pb, Cd, and Cu. This study was inspired by our efforts to detoxify fly ash from municipal solid waste incineration by thermal treatment to produce secondary raw materials suited for reprocessing. The potential of the thermal treatment was studied by monitoring the evaporation rate of zinc from a certified fly ash (BCR176) during heating between 300 and 950 degrees C under different carrier gas compositions. Samples were quenched at different temperatures for subsequent investigation with X-ray absorption spectroscopy (XAS). The XAS spectra were analyzed using principal component analysis (PCA), target transformation (TT), and linear combination fitting (LCF) to analyze the major Zn compounds in the fly ash as a function of the temperature. The original fly ash comprised about 60% zinc oxides mainly in the form of hydrozincite (Zn5(OH)6(CO3)2) and 40% inerts like willemite (Zn2SiO4) and gahnite (ZnAl2O4) in a weight ratio of about 3:1. At intermediate temperatures (550-750 degrees C) the speciation underlines the competition between indigenous S and Cl with solid zinc oxides to form either volatile ZnCl2 or solid ZnS. ZnS then transformed into volatile species at about 200 degrees C higher temperatures. The inhibiting influence of S was found absent when oxygen was introduced to the inert carrier gas stream or chloride-donating alkali salt was added to the fly ash.


Asunto(s)
Contaminación del Aire/prevención & control , Carbono , Incineración , Eliminación de Residuos/métodos , Zinc/química , Ceniza del Carbón , Material Particulado , Análisis de Componente Principal , Análisis Espectral , Temperatura , Rayos X
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