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1.
BMC Med Educ ; 19(1): 48, 2019 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-30732614

RESUMEN

BACKGROUND: To meet the patients' needs and to provide adequate health care, students need to be prepared for interprofessional collaborative practice during their undergraduate education. On interprofessional training wards (IPTW) undergraduates of various health care professions potentially develop a mutual understanding and improve their interprofessional competencies in clinical practice. To enhance collaboration of 6th-year medical students and nursing trainees in the third year of their vocational training an IPTW (Heidelberger Interprofessionelle Ausbildungsstation - HIPSTA) was implemented at the University Hospital Heidelberg, Germany. On HIPSTA future physicians and nurses take care of the patients self responsibly and in close interprofessional collaboration, supervised by facilitators of both professions. Although there are positive experiences with IPTWs internationally, little is known about the impact of IPTW on the acquisition of interprofessional competencies. For future interprofessional training and implementation of IPTWs evaluation of interprofessional learning and collaborative practice on Germany's first IPTW is of high relevance. METHODS: To evaluate the acquisition of interprofessional competencies the study follows a mixed-methods approach. Quantitative data is collected from undergraduate participants, staff participants and facilitators on HIPSTA (intervention group) and undergraduate participants and staff participants on a comparable 'conventional' ward without special interprofessional training (comparison group) immediately pre and post HIPSTA and, as follow-up, after three to six months (T0, T1, T2), using three questionnaires, namely the University of the West of England Interprofessional Questionnaire (UWE-IP), the Interprofessional Socialization and Valuing Scale (ISVS) and the Assessment of Interprofessional Team Collaboration Scale (AITCS). Qualitative data is gathered in form of interviews and focus groups based on semi structured guidelines, video recordings of handovers and overt non-participant observations of daily rounds. Quantitative data will be analysed in a longitudinal comparison, presented descriptively and tested with an analysis of variance. Qualitative data will be analysed deductively and inductively. DISCUSSION: The results of the evaluation will give insight in undergraduates', staff's and facilitators' experiences and their self-perception of competency development. In addition the results will help identify benefits, challenges and areas for modification when implementing and establishing similar interprofessional training wards.


Asunto(s)
Competencia Clínica/normas , Educación de Pregrado en Medicina , Relaciones Interprofesionales , Estudiantes de Medicina , Adulto , Actitud del Personal de Salud , Educación de Pregrado en Medicina/normas , Femenino , Alemania , Humanos , Comunicación Interdisciplinaria , Estudios Longitudinales , Masculino , Grupo de Atención al Paciente , Aprendizaje Basado en Problemas , Evaluación de Programas y Proyectos de Salud , Estudios Prospectivos , Investigación Cualitativa , Estudiantes de Medicina/psicología
2.
GMS J Med Educ ; 35(3): Doc33, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30186943

RESUMEN

Background: Deficits in care and impaired patient-safety have been linked to inefficient interprofessional collaborative practice. Interprofessional training wards (IPTW) are an interprofessional educational intervention which aim to enable students and trainees from different health professions to work self-responsibly in order to manage the medical treatment and rehabilitation of real-life patients together as an interprofessional team. We aimed to develop and implement Germany´s first IPTW at the department of Surgery at Heidelberg University Hospital. Methods: The Kern cycle was used to develop an ITPW curriculum. Practical as well as theoretical considerations guided the design of the IPTW. Common project management tools including blueprinting and RASCI (Responsibility, Approval, Support, Consultation, Information) matrix were applied. Results: Since April 2017, 7 cohorts of students and trainees have had four-week long placements on HIPSTA. They run the IPTW in early and late shifts. Nursing and medical facilitators are supporting the IP team as needed. Learning objectives are operationalized as EPAs (entrustable professional activities) and interprofessional learning goals. Since initiation only minor modifications to the curriculum have been necessary and satisfaction of students/trainees, facilitators and patients is high. Conclusion: IPTWs can be established and run in the German health care system even in a complex clinical setting. The early involvement of all professions in a steering group seems to be key to success. Nursing and medical facilitators are of utmost importance for daily routine. The experiences outlined here could help others aiming to implement IPTWs at their sites. IPTWs might address a number of hitherto unaddressed educational needs. Trial registration: Not applicable.


Asunto(s)
Empleos en Salud , Estudiantes de Enfermería , Austria , Alemania , Humanos , Relaciones Interprofesionales , Suiza
3.
J Mater Sci Mater Med ; 29(5): 64, 2018 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-29737411

RESUMEN

Mesoporous bioactive glass (BG) nanoparticles based in the system: SiO2-P2O5-CaO-MnO were synthesized via a modified Stöber process at various concentrations of Mn (0-7 mol %). The synthesized manganese-doped BG nanoparticles were characterized in terms of morphology, composition, in vitro bioactivity and antibacterial activity. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET) analysis confirmed that the particles had spherical morphology (mean particle size: 110 nm) with disordered mesoporous structure. Energy dispersive X-ray spectroscopy (EDX) confirmed the presence of Mn, Ca, Si and P in the synthesized Mn-doped BG particles. Moreover, X-ray diffraction (XRD) analysis showed that Mn has been incorporated in the amorphous silica network (bioactive glass). Moreover, it was found that manganese-doped BG particles form apatite crystals upon immersion in simulated body fluid (SBF). Inductively coupled plasma atomic emission spectroscopy (ICP-OES) measurements confirmed that Mn is released in a sustained manner, which provided antibacterial effect against Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus. The results indicate that the incorporation of Mn in the bioactive glass network is an effective strategy to develop novel multifunctional BG nanoparticles for bone tissue engineering.


Asunto(s)
Materiales Biocompatibles/síntesis química , Manganeso/química , Nanopartículas/química , Dióxido de Silicio/química , Materiales Biocompatibles/química , Líquidos Corporales/química , Vidrio/química , Humanos , Ensayo de Materiales , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Nanomedicina/métodos , Porosidad , Dióxido de Silicio/síntesis química , Espectrometría por Rayos X , Difracción de Rayos X
4.
Langmuir ; 33(47): 13581-13589, 2017 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-29099602

RESUMEN

We report on the tailoring of ZnO nanoparticle (NP) surfaces by catechol derivatives (CAT) with different functionalities: tert-butyl group (tertCAT), hydrogen (pyroCAT), aromatic ring (naphCAT), ester group (esterCAT), and nitro group (nitroCAT). The influence of electron-donating/-withdrawing properties on enthalpy of ligand binding (ΔH) was resolved and subsequently linked with optical properties. First, as confirmed by ultraviolet/visible (UV/vis) and Fourier transform infrared (FT-IR) spectroscopy results, all CAT molecules chemisorbed to ZnO NPs, independent of the distinct functionality. Interestingly, the ζ-potentials of ZnO after functionalization shifted to more negative values. Then, isothermal titration calorimetry (ITC) and a mass-based method were applied to resolve the heat release during ligand binding and the adsorption isotherm, respectively. However, both heat- and mass-based approaches alone did not fully resolve the binding enthalpy of each molecule adsorbing to the ZnO surface. This is mainly due to the fact that the Langmuir model oversimplifies the underlying adsorption mechanism, at least for some of the tested CAT molecules. Therefore, a new, fitting-free approach was developed to directly access the adsorption enthalpy per molecule during functionalization by dividing the heat release measured via ITC by the amount of bound molecules determined from the adsorption isotherm. Finally, the efficiency of quenching the visible emission caused by ligand binding was investigated by photoluminescence (PL) spectroscopy, which turned out to follow the same trend as the binding enthalpy. Thus, the functionality of ligand molecules governs the binding enthalpy to the particle surface, which in turn, at least in the current case of ZnO, is an important parameter for the quenching of visible emission. We believe that establishing such correlations is an important step toward a more general way of selecting and designing ligand molecules for surface functionalization. This allows developing strategies for tailored colloidal surfaces beyond empirically driven formulation on a case by case basis.

5.
J Biomed Mater Res A ; 105(10): 2772-2782, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28571113

RESUMEN

Bioactive glasses (BAGs) are highly interesting materials for bone regeneration applications in orthopedic and dental defects. It is quite well known that ionic release from BAGs influences cell behavior and function. Mindful of the clinical scenario, we hypothesized that local cell populations might additionally physically interact with the implanted BAG particles and respond differently than to just the ionic stimuli. We therefore studied the biological effect of two BAG types (45S5 and 1393) applied to human mesenchymal stromal cells (hMSCs) in three distinct presentation modes: (a) direct contact; and to dissolution products in (b) 2D, and (c) 3D culture. We furthermore investigated how the dose-dependence of these BAG particles, in concentrations ranging from 0.1 to 2.5 w/v %, influenced hMSC metabolic activity, proliferation, and cell spreading. These cellular functions were significantly hampered when hMSCs were exposed to high concentrations of either glasses, but the effects were more pronounced in the 45S5 groups and when the cells were in direct contact with the BAGs. Furthermore the biological effect of 1393 BAG outperformed that of 45S5 BAG in all tested presentation modes. These outcomes highlight the importance of investigating cell-BAG interactions in experimental set-ups that recapitulate host cell interactions with BAG particles. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2772-2782, 2017.


Asunto(s)
Materiales Biocompatibles/metabolismo , Cerámica/metabolismo , Células Madre Mesenquimatosas/citología , Movimiento Celular , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Vidrio , Humanos , Iones/metabolismo , Masculino , Células Madre Mesenquimatosas/metabolismo
6.
Adv Mater ; 29(5)2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27886413

RESUMEN

Ball milling TiO2 anatase together with TiH2 can create an effective photocatalyst. The process changes the lattice and electronic structure of anatase. Lattice deformation created by mechanical impact combined with hydride incorporation yield electronic gap-states close to the conduction band of anatase. These provide longer lifetimes of photogenerated charge carriers and lead to an intrinsic cocatalytic activation of anatase for H2 evolution.

7.
Eur J Pharm Biopharm ; 98: 98-107, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26592155

RESUMEN

The effect of four structurally different polymer species (hydroxypropylcellulose, polyvinylpyrrolidone, vinylpyrrolidone-vinyl acetate copolymer and polyvinyl alcohol) on the production of mefenamic acid nanoparticles during media milling has been studied. It was found that product particle sizes are strongly determined by the type of polymeric stabiliser as well as by its concentration at constant process conditions. With respect to small product particle sizes an optimum excipient concentration was identified and adjusted for colloidal stability of the drug nanosuspensions. Furthermore, it was found that overdosing of excipients must be omitted to suppress ripening due to enhanced solubilisation phenomena. Hence, the smallest product particle sizes were obtained using a polymeric stabiliser which exhibits a high affinity to the model drug compound and a low solubilisation capacity. Affinities of each polymer species to mefenamic acid and corresponding surface concentrations were determined using straightforward and simple viscosity measurements of the supernatant. A relationship between polymer affinity, solubilisation capacity and limiting product particle size has been observed, which supports the hypothesis that final product particle sizes are rather determined by the solid-liquid equilibrium than by pure mechanical fracture.


Asunto(s)
Ácido Mefenámico/química , Nanopartículas/química , Polímeros/química , Tecnología Farmacéutica , Rastreo Diferencial de Calorimetría , Química Farmacéutica , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier
8.
Sci Rep ; 4: 6227, 2014 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-25178812

RESUMEN

We study the packing of fine glass powders of mean particle diameter in the range (4-52) µm both experimentally and by numerical DEM simulations. We obtain quantitative agreement between the experimental and numerical results, if both types of attractive forces of particle interaction, adhesion and non-bonded van der Waals forces are taken into account. Our results suggest that considering only viscoelastic and adhesive forces in DEM simulations may lead to incorrect numerical predictions of the behavior of fine powders. Based on the results from simulations and experiments, we propose a mathematical expression to estimate the packing fraction of fine polydisperse powders as a function of the average particle size.

9.
J Biomed Mater Res B Appl Biomater ; 102(5): 952-61, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25050444

RESUMEN

In this study in vitro bioactivity and biocompatibility of two submicron 45S5 Bioglass® powders obtained by topdown processing have been evaluated and are compared to the as-received powder. Both submicron powders exhibited flake-like morphologies with lateral extensions of only a few microns; the flake thickness accounted for a few tens of nanometers. Enhanced in vitro bioactivity was found for the comminuted powders upon immersion in simulated body fluid. In vitro biocompatibility was evaluated by incubation of MG-63 osteoblast-like cells with various amounts (0­200 µg/mL) of the glass powders. Neither LDH-activity nor mitochondrial activity (WST-8) tests indicated cell toxicity. Increased mitochondrial activity was found for the submicron powders: incubation with high amounts revealed up to a threefold increase of osteoblast activity (ALP-activity). An overgrowth of the formed mineralized phase with phenotypical MG-63 cells was found by staining only for the submicron glasses. A distance ring is formed for the as-received powder. Superior bioactivity markers are found for shorter process times, that is, lower mass specific surface areas. This is attributed to the formation of carbonates during the comminution process.


Asunto(s)
Cerámica/farmacología , L-Lactato Deshidrogenasa/metabolismo , Ensayo de Materiales , Mitocondrias/metabolismo , Osteoblastos/metabolismo , Línea Celular , Cerámica/química , Humanos , Osteoblastos/citología , Tamaño de la Partícula , Polvos
10.
ACS Appl Mater Interfaces ; 6(4): 2865-77, 2014 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-24476347

RESUMEN

Loading biomaterials with angiogenic therapeutics has emerged as a promising approach for developing superior biomaterials for engineering bone constructs. In this context, cobalt-releasing materials are of interest as Co is a known angiogenic agent. In this study, we report on cobalt-releasing three-dimensional (3D) scaffolds based on a silicate bioactive glass. Novel melt-derived "1393" glass (53 wt % SiO2, 6 wt % Na2O, 12 wt % K2O, 5 wt % MgO, 20 wt % CaO, and 4 wt % P2O5) with CoO substituted for CaO was fabricated and was used to produce a 3D porous scaffold by the foam replica technique. Glass structural and thermal properties as well as scaffold macrostructure, compressive strength, acellular bioactivity, and Co release in simulated body fluid (SBF) were investigated. In particular, detailed insights into the physicochemical reactions occurring at the scaffold-fluid interface were derived from advanced micro-particle-induced X-ray emission/Rutherford backscattering spectrometry analysis. CoO is shown to act in a concentration-dependent manner as both a network former and a network modifier. At a concentration of 5 wt % CoO, the glass transition point (Tg) of the glass was reduced because of the replacement of stronger Si-O bonds with Co-O bonds in the glass network. Compressive strengths of >2 MPa were measured for Co-containing 1393-derived scaffolds, which are comparable to values of human spongy bone. SBF studies showed that all glass scaffolds form a calcium phosphate (CaP) layer, and for 1393-1Co and 1393-5Co, CaP layers with incorporated traces of Co were observed. The highest Co concentrations of ∼12 ppm were released in SBF after reaction for 21 days, which are known to be within therapeutic ranges reported for Co(2+) ions.


Asunto(s)
Materiales Biocompatibles , Desarrollo Óseo , Cobalto/química , Vidrio , Ingeniería de Tejidos , Andamios del Tejido , Microscopía Electrónica de Rastreo
11.
J Colloid Interface Sci ; 386(1): 240-51, 2012 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-22925119

RESUMEN

The conductivity behavior of doped hydrocarbon systems is studied by applying impedance spectroscopy. In the case of 3,5-diisopropyl salicylato aluminum (III) the charge carriers are formed by dissociation of the compound and their concentration is proportional to the square root of the solute concentration. In hydrocarbon systems that consist of micelle forming compounds (sodium AOT/ lecithin) a linear dependence of charge carrier concentration on solute concentration is observed in the concentration regime where micelles are present. The conduction mechanisms are studied by numerical solution of a Poisson-Nernst-Planck system that describes the charge transport. We follow two different approaches to extract the degree of micelle dissociation from the impedance data. Firstly, by computing the response of a linear approximation of the Poisson-Nernst-Planck model, and secondly by computing the fully nonlinear response from direct numerical simulations using finite elements. For high and moderate frequencies both approaches agree very well with the experimental data. For small frequencies the response becomes nonlinear and the concept of impedance fails. Furthermore, the numerically computed values for the degree of dissociation are of the same order of magnitude as the values obtained with classical formulas, but still differ by a factor of about 1/3. The direct numerical simulation allows new insight into the conduction mechanisms for different frequency regimes.


Asunto(s)
Alcanos/química , Aluminio/química , Conductividad Eléctrica , Lecitinas/química , Modelos Teóricos , Salicilatos/química , Micelas , Temperatura Ambiental
12.
Environ Manage ; 48(1): 198-211, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21365272

RESUMEN

Increasing demand for global food production is leading to greater use of irrigation to supplement rainfall and enable more intensive use of land. Minimizing adverse impacts of this intensification on surface water and groundwater resources is of critical importance for the achievement of sustainable land use. In this paper we examine the linkages between irrigation runoff and resulting changes in quality of receiving surface waters and groundwaters in Australia and New Zealand. Case studies are used to illustrate impacts under different irrigation techniques (notably flood and sprinkler systems) and land uses, particularly where irrigation has led to intensification of land use. For flood irrigation, changes in surface water contaminant concentrations are directly influenced by the amount of runoff, and the intensity and kind of land use. Mitigation for flood irrigation is best achieved by optimizing irrigation efficiency. For sprinkler irrigation, leaching to groundwater is the main transport path for contaminants, notably nitrate. Mitigation measures for sprinkler irrigation should take into account irrigation efficiency and the proximity of intensive land uses to sensitive waters. Relating contaminant concentrations in receiving groundwaters to their dominant causes is often complicated by uncertainty about the subsurface flow paths and the possible pollutant sources, viz. drainage from irrigated land. This highlights the need for identification of the patterns and dynamics of surface and subsurface waters to identify such sources of contaminants and minimize their impacts on the receiving environments.


Asunto(s)
Riego Agrícola , Ríos , Microbiología del Agua , Contaminación del Agua , Australia , Nueva Zelanda
13.
J Phys Chem B ; 114(18): 6150-5, 2010 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-20397676

RESUMEN

We present a detailed calculation of partial charges for the 1,3-dimethylimidazolium chloride ionic liquid. We first analyze MP2 electronic structure calculations and DFT results on isolated ion pairs with various methods of assigning partial charges to the atomic centers. In a second run we analyze the trajectory of a 25 ps long Car-Parrinello MD run of 30 ion pairs under bulk conditions using a charge fitting procedure due to Blöchl. Both, the single ion pair and the bulk system, provide us with a similar total ionic charge considerably less than unity. Especially the liquid state DFT results give convincing evidence for a reduced ionic charge on the ions. The similarity of both results suggest that the delocalization of the Cl charge is due only to local interactions. The relevance of our results is 2-fold; on the one hand they shed light on the basic property of the liquid and its reduced ionic character, and on the other hand, the ab initio derived partial charges provide a fundamental theoretical basis for the recent attempts to use the total ionic charge as an adjustable parameter. Furthermore, all our partial charges are subject to large fluctuations, hinting to the importance of polarization effects.

14.
J Phys Chem B ; 113(35): 11959-64, 2009 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-19663399

RESUMEN

We present herein a comprehensive density functional theory study toward assessing the accuracy of two popular gradient-corrected exchange correlation functionals on the structure and density of liquid water at near ambient conditions in the isobaric-isothermal ensemble. Our results indicate that both PBE and BLYP functionals under predict the density and over structure the liquid. Adding the dispersion correction due to Grimme (1, 2) improves the predicted densities for both BLYP and PBE in a significant manner. Moreover, the addition of the dispersion correction for BLYP yields an oxygen-oxygen radial distribution function in excellent agreement with experiment. Thus, we conclude that one can obtain a very satisfactory model for water using BLYP and a correction for dispersion.

15.
Inhal Toxicol ; 21 Suppl 1: 8-16, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19558228

RESUMEN

The dissolution behaviour of an oxidic nanoparticle in a small volume of solvent was investigated. The results of thermodynamic and kinetic calculations are presented. Variations in nanoparticle size and solvent volume are considered. Two kinds of final states of the system can be formed. One state is a homogeneous monomolecular solution of the dissolved species; the other one is a system in stable equilibrium between nanoparticle and solvent. What kind of state is formed depends on the size of the nanoparticle and the amount of solvent. The concentration of the dissolved species is much higher than the saturation concentration of the bulk material in many cases. An unusual dissolution behaviour of an ensemble of nanoparticles, called kinetic size effect, follows from the calculations. A very high concentration is found of the dissolved material at the beginning of the dissolution process. The concentration decreases at longer dissolution times. As an example, the experimental results of the dissolution kinetics of an ensemble of nanoparticles of commercial titanium dioxide in water are presented. Good agreement between experimental results and theoretical calculations is found. From these data it can be deduced that a nanoparticle with a radius of 14.15 nm dissolves in a volume of water of 18 microm(3) until its radius becomes 13.77 nm and a stable system nanoparticle-dissolved substance-solvent is formed (supersaturation 24), whereas a nanoparticle of radius 11.4 nm is completely dissolved after 73 h (supersaturation 165). The effect is established for different oxides.


Asunto(s)
Microquímica , Modelos Químicos , Nanopartículas/química , Solventes/química , Titanio/química , Agua/química , Cinética , Tamaño de la Partícula , Reproducibilidad de los Resultados , Solubilidad , Termodinámica
17.
J Chem Phys ; 129(22): 224501, 2008 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-19071922

RESUMEN

The influences of two different commonly employed force fields on statical and dynamical properties of ionic liquids are investigated for [EMIM][BF(4)]. The force fields compared in this work are the one of Canongia Lopes and Padua [J. Phys. Chem. B 110, 19586 (2006)] and that of Liu et al. [J. Phys. Chem. B 108, 12978 (2004)]. Differences in the strengths of hydrogen bonds are found, which are also reflected in the static ion distributions around the cation. Moreover, due to the stronger hydrogen bonding in the force field of Liu et al., the diffusive motions of cations and anions and the rotational behavior of the cations are slower compared with those obtained with the force field of Canongia Lopes and Padua. Both force fields underestimate the zero-field electrical conductivity, while the experimental dielectric constant can be reproduced within the expected statistical error boundaries.

18.
J Chem Phys ; 129(17): 174503, 2008 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-19045354

RESUMEN

The 1,3-dimethyl imidazolium chloride [MMIM]Cl is an example of ionic liquid and frequently studied in literature. In this article [MMIM]Cl is studied using an ab initio method [second order Moller-Plesset perturbation theory (MP2), density functional theory (DFT)] and classical force field approach with the aim of looking at some properties on different scales. Selected properties are studied with the different methods and compared to each other. The comparison between the results obtained with MP2 and the DFT approach allows us to comment on the validity of this latter and thus on its employment in larger systems. On the other hand, the comparison between the DFT results and those of the classical approach allows us to test the reproducibility of electrostatic properties by this latter approach. As the results show the used DFT setup is rather satisfactory, while the classical force fields are describing the electrostatic properties in an insufficient way. A revision (improvement) of the classical force fields is at this stage necessary in order to capture the electrostatic properties in a proper way.

20.
Phys Rev Lett ; 99(26): 263001, 2007 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-18233573

RESUMEN

Spin echo formation in magnetic field gradients in the presence of fast stochastic motion is studied for hyperpolarized 3He gas at different diffusivities. The fast translational motion leads to frequency shifts already during echo formation, which can be described analytically for a linear gradient. Despite complete signal loss at the position of the spin echo itself, considerable intensity can be preserved at an earlier time (sqrt[2]tau rather than 2tau, where tau is the pulse delay). Hence, the phenomenon is designated as a pseudo spin echo.

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