RESUMO
With the continuing interest in new magnetic materials for sensor devices and data storage applications, the community needs reliable and sensitive tools for the characterization of such materials. Soft X-rays tuned to elemental absorption edges are a depth and element sensitive probe of magnetic structure at the nanoscale, and scattering measurements have the potential to provide 3D magnetic structural information of the material. In this work we develop a methodology in transmission geometry that allows one to probe the spatial distribution of the magnetization along the different layers of magnetic heterostructures. We study the in-plane/out-of-plane transition of magnetic domains in multilayer thin film systems consisting of two layers of NiFe top and bottom, and a 50 repeat Co/Pd multilayer in the centre. The experimental data are analysed by simulating scattering data starting from micromagnetic simulations, and we find that the out of plane domains of the Co/Pd multilayer intrude into the NiFe layers to a greater extent than would be expected from micromagnetic simulations performed using the standard magnetically isotropic input parameters for the NiFe layers.
Assuntos
Humanos , Insuficiência de Múltiplos Órgãos/terapia , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Síndrome de Resposta Inflamatória Sistêmica/terapia , Adjuvantes Imunológicos/farmacologia , Água Corporal/fisiologia , Permeabilidade Capilar , Coloides/farmacologia , Hemofiltração , Necessidades Nutricionais , Respiração Artificial , Reanimação Cardiopulmonar , Síndrome de Resposta Inflamatória Sistêmica/tratamento farmacológico , Equilíbrio HidroeletrolíticoRESUMO
We studied the pharmacokinetics and clearence of a 200 mg ciprofloxacin and a 500 mg amikacin intravenous dose during 5 continuous hemodialysis procedures in 5 patients with acute oliguric renal failure. Hourly blood and ultrafiltrate drug concentrations were measured during 8 hours. Dialysate flux (Qd) was 16.6 ml/min during the first hours and 33.2 ml/min thereafter. For each Qd, total ciprofloxacin clearence was 1.13ñ0.99 and 2.8ñ1.71 ml/min (p<0.001), diffusive clearence was 0.96ñ0.87 and 2.47ñ1.56 ml/min (p<0.005) and convective clearence was 0.16ñ0.17 and 0.33ñ0.2 ml/min (p<0.05). Likewise, total amikacin clearence was 3.47ñ1.31 and 4.18ñ0.53 ml/min (p<0.001), diffusive clearence was 2.97ñ1.24 and 3.86ñ0.52 ml/min and convective clearence was 0.50ñ0.47 and 0.32ñ0.29 ml/min (p=NS). Protein binding was 84 percent for ciprofloxacin and 77 percent for amikacin. It is concluded that during continuous hemodialysis with cuprofan membrane, the main transport mechanism of ciprofloxacin and amikacin is diffusive. Very low amounts of ciprofloxacin are depurated by the dialyser. Likewise, the shortening of amikacin half life suggest the presence of other elimination pathway and the need to use suplementary doses every 24 hours