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1.
Rev Sci Instrum ; 94(1): 013906, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36725613

RESUMEN

We present an in situ uniaxial pressure device optimized for small angle x-ray and neutron scattering experiments at low-temperatures and high magnetic fields. A stepper motor generates force, which is transmitted to the sample via a rod with an integrated transducer that continuously monitors the force. The device has been designed to generate forces up to 200 N in both compressive and tensile configurations, and a feedback control allows operating the system in a continuous-pressure mode as the temperature is changed. The uniaxial pressure device can be used for various instruments and multiple cryostats through simple and exchangeable adapters. It is compatible with multiple sample holders, which can be easily changed depending on the sample properties and the desired experiment and allow rapid sample changes.

2.
J Synchrotron Radiat ; 22(4): 908-24, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26134794

RESUMEN

A detailed description is presented of the Extreme Conditions Beamline P02.2 for micro X-ray diffraction studies of matter at simultaneous high pressure and high/low temperatures at PETRA III, in Hamburg, Germany. This includes performance of the X-ray optics and instrumental resolution as well as an overview of the different sample environments available for high-pressure studies in the diamond anvil cell. Particularly emphasized are the high-brilliance and high-energy X-ray diffraction capabilities of the beamline in conjunction with the use of fast area detectors to conduct time-resolved compression studies in the millisecond time regime. Finally, the current capability of the Extreme Conditions Science Infrastructure to support high-pressure research at the Extreme Conditions Beamline and other PETRA III beamlines is described.

3.
J Synchrotron Radiat ; 20(Pt 4): 541-9, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23765295

RESUMEN

The resonant scattering and diffraction beamline P09 at PETRA III is designed for X-ray experiments requiring small beams, energy tunability, variable polarization and high photon flux. It is highly flexible in terms of beam size and offers full higher harmonic suppression. A state-of-the-art double phase-retarder set-up provides variable linear or circular polarization. A high-precision Psi-diffractometer and a heavy-load diffractometer in horizontal Psi-geometry allow the accommodation of a wide variety of sample environments. A 14 T cryo-magnet is available for scattering experiments in magnetic fields.

4.
Diabetologia ; 52(8): 1496-503, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19526212

RESUMEN

AIMS/HYPOTHESIS: This study was designed to investigate the use and impact of a continuous glucose monitoring system (the FreeStyle Navigator) under home-use conditions in the self-management of type 1 diabetes. METHODS: A 20 day masked phase, when real-time data and alarms were not available, was compared with a subsequent 40 day unmasked phase for a number of specified measures of glycaemic variability. HbA(1c) (measured by DCA 2000) and a hypoglycaemia fear survey were recorded at the start and end of the study. RESULTS: The study included 48 patients with type 1 diabetes (mean age 35.7 +/- 10.9, range 18-61 years; diabetes duration 17.0 +/- 9.5 years). Two patients did not complete the study for personal reasons. Comparing masked (all 20 days) and unmasked (last 20 days) phases, the following reductions were seen: time outside euglycaemia from 11.0 to 9.5 h/day (p = 0.002); glucose SD from 3.5 to 3.2 mmol/l (p < 0.001); hyperglycaemic time (>10.0 mmol/l) from 10.3 to 8.9 h/day (p = 0.0035); mean amplitude of glycaemic excursions (peak to nadir) down by 10% (p < 0.001); high blood glucose index down by 18% (p = 0.0014); and glycaemic risk assessment diabetes equation score down by 12% (p = 0.0013). Hypoglycaemic time (<3.9 mmol/l) decreased from 0.70 to 0.64 h/day without statistical significance (p > 0.05). Mean HbA(1c) fell from 7.6 +/- 1.1% at baseline to 7.1 +/- 1.1% (p < 0.001). In the hypoglycaemia fear survey, the patients tended to take less snacks at night-time after wearing the sensor. CONCLUSIONS/INTERPRETATION: Home use of a continuous glucose monitoring system has a positive effect on the self-management of diabetes. Thus, continuous glucose monitoring may be a useful tool to decrease glycaemic variability.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 1/sangre , Hemoglobina Glucada/metabolismo , Monitoreo Ambulatorio/métodos , Autocuidado/normas , Adolescente , Adulto , Humanos , Hiperglucemia/sangre , Hipoglucemia/sangre , Persona de Mediana Edad , Medición de Riesgo , Tecnología/tendencias , Adulto Joven
5.
Forensic Sci Int ; 171(1): 78-83, 2007 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-17010548

RESUMEN

Free floating thrombus in the ascending aorta is an uncommon source of acute myocardial infarction. We report on two cases of young women who died of acute myocardial infarction caused by a free floating thrombus in the sinus of Valsalva obstructing the coronary arteries' ostia. The first case reports on a 30-year-old pregnant woman who anamnestically had episodes with short loss of consciousness and weakness. The second case presents a 37-year-old woman suffering from multiple sclerosis with no previous history of thrombotic events. The review of literature revealed a predominance of women (eight females and three males). Interestingly, the coronary arteries bear no preference concerning the right (RCA) or left coronary artery (LCA) being more often occluded by a free floating thrombus. Especially, younger women (mean age 45.5 years, range 30-59 years) with no history of cardiac symptoms and without atherosclerotic changes seem to be predispositioned. The hypothesis that thrombus formation in cases without plaque disruption may depend on an endothelial erosion which seems to be more common in younger women and promoted by a hyperthrombogenic state is supported by our two cases. A comprehensive literature search revealed, that these are the first two reports on a free floating thrombus being the cause of fatal acute myocardial infarction in a pregnant woman, respectively, a woman suffering from multiple sclerosis.


Asunto(s)
Enfermedades de la Aorta/complicaciones , Enfermedades de la Aorta/patología , Infarto del Miocardio/etiología , Trombosis/complicaciones , Trombosis/patología , Adulto , Aorta/patología , Estenosis Coronaria/patología , Vasos Coronarios/patología , Resultado Fatal , Femenino , Patologia Forense , Humanos , Esclerosis Múltiple/complicaciones , Infarto del Miocardio/patología , Embarazo , Complicaciones Cardiovasculares del Embarazo/patología
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