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1.
Microsc Microanal ; 23(4): 878-890, 2017 08.
Article in English | MEDLINE | ID: mdl-28641595

ABSTRACT

The history and iconography of Swiss stained glass dating between the 16th and 18th centuries are well studied. However, the chemical and morphological characteristics of the glass and glass paints, particularly the nature of the raw materials, the provenance of the glass, and the technology used to produce it are less well understood. In this paper, we studied two sets of samples from stained-glass panels attributed to Switzerland, which date from the 16th to 17th centuries: the first set comes from Pena National Palace collection, the second from Vitrocentre Romont. The aims were to identify the materials used in the production of the glass, to find out more about their production origin and to characterize the glass paints. Both glass and the glass paints were analysed by particle-induced X-ray emission; the paints were additionally analysed by scanning electron microscopy-electron-dispersive X-ray spectroscopy (SEM-EDS). The results show that the glass from both sets was probably produced in the same region and that wood ash was used as a fluxing agent. Different recipes have been used to make the blue enamels. However, the cobalt ore used as a coloring agent in all of the blue enamels came from the mining district in Schneeberg, Germany.

2.
IEEE Trans Image Process ; 25(10): 4475-88, 2016 10.
Article in English | MEDLINE | ID: mdl-27416590

ABSTRACT

Stained glass windows are designed to reveal their powerful artistry under diverse and time-varying lighting conditions; virtual relighting of stained glass, therefore, represents an exceptional tool for the appreciation of this age old art form. However, as opposed to most other artifacts, stained glass windows are extremely difficult if not impossible to analyze using controlled illumination because of their size and position. In this paper, we present novel methods built upon image based priors to perform virtual relighting of stained glass artwork by acquiring the actual light transport properties of a given artifact. In a preprocessing step, we build a material-dependent dictionary for light transport by studying the scattering properties of glass samples in a laboratory setup. We can now use the dictionary to recover a light transport matrix in two ways: under controlled illuminations the dictionary constitutes a sparsifying basis for a compressive sensing acquisition, while in the case of uncontrolled illuminations the dictionary is used to perform sparse regularization. The proposed basis preserves volume impurities and we show that the retrieved light transport matrix is heterogeneous, as in the case of real world objects. We present the rendering results of several stained glass artifacts, including the Rose Window of the Cathedral of Lausanne, digitized using the presented methods.

3.
Anal Bioanal Chem ; 407(3): 1023-6, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25240935

ABSTRACT

Low gas flow ICP-OES with a total argon consumption below 0.7 L/min is introduced for the analysis of trace elements in blood samples to investigate the influence of samples containing an organic solvent in a demanding matrix on the performance of this plasma for the first time. Therefore, gadolinium was determined in human plasma samples and mercury in red blood cells, human plasma, and precipitated plasma protein fraction. Limits of detection (LOD) were determined to be in the low microgram per liter range for the analytes and the accuracy of the method was assessed by comparison with a conventional Fassel-type torch-based ICP-OES. It was proven that the low gas flow ICP-OES leads to comparable results with the instrument based on the Fassel-type torch.


Subject(s)
Blood Chemical Analysis/methods , Mercury/blood , Spectrophotometry/methods , Argon , Equipment Design , Erythrocytes/chemistry , Gadolinium/blood , Gadolinium DTPA/therapeutic use , Humans , Limit of Detection , Spectrophotometry/instrumentation
4.
J Trace Elem Med Biol ; 28(2): 125-130, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24613139

ABSTRACT

Because of its bactericidal and fungicidal properties, thimerosal is used as a preservative in drugs and vaccines and is thus deliberately injected into the human body. In aqueous environment, it decomposes into thiosalicylic acid and the ethylmercury cation. This organomercury fragment is a potent neurotoxin and is suspected to have similar toxicity and bioavailability like the methylmercury cation. In this work, human whole blood and physiological simulation solutions were incubated with thimerosal to investigate its behaviour and binding partners in the blood stream. Inductively coupled plasma with optical emission spectrometry (ICP-OES) was used for total mercury determination in different blood fractions, while liquid chromatography (LC) coupled to electrospray ionisation time-of-flight (ESI-TOF) and inductively coupled plasma-mass spectrometry (ICP-MS) provided information on the individual mercury species in plasma surrogate samples. Analogous behaviour of methylmercury and ethylmercury species in human blood was shown and an ethylmercury-glutathione adduct was identified.


Subject(s)
In Vitro Techniques/methods , Plasma/metabolism , Thimerosal/blood , Chromatography, Liquid , Cysteine/blood , Glutathione/blood , Humans , Spectrometry, Mass, Electrospray Ionization , Spectrophotometry, Atomic
5.
Article in German | MEDLINE | ID: mdl-25575231

ABSTRACT

Medical concepts and strategies are permanently changing. Due to the emergency response in a mass casualty incident everyone who is involved has to work together with different organisations and public authorities, which are not part of the regular emergency medical service. Within the last 25 years throughout the whole country of Germany the role of a "chief emergency physician" has been implemented and in preparation for the FIFA World Cup 2006 mobile treatment units were set up. In 2007, special units of the "Medical Task Force" - funded by the german state - were introduced and have been established by now. They will be a permanent part of regional plannings for mass casualty incidents. This article highlights current concepts and developments in different parts of Germany.


Subject(s)
Mass Casualty Incidents , Disaster Planning , Emergency Medical Services/statistics & numerical data , Emergency Service, Hospital , Germany , Humans , Physicians
6.
Anal Bioanal Chem ; 395(6): 1929-35, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19768643

ABSTRACT

To investigate the effects of mercury species intoxication and to test the efficiency of different commonly applied antidotes, human whole blood and plasma surrogate samples were spiked with inorganic mercury (Hg2+) and methylmercury (MeHg+, CH3Hg+) prior to treatment with the antidotes 2,3-dimercaptopropan-1-ol (British Anti Lewisite), 2,3-dimercaptosuccinic acid (DMSA), and N-acetylcysteine (NAC). For mercury speciation analysis in these samples, liquid chromatography was coupled to either inductively coupled plasma mass spectrometry (ICP-MS) or electrospray ionisation time-of-flight mass spectrometry (ESI-TOF-MS). Adduct formation between mercury species and physiological thiols (cysteine and glutathione) was observed as well as the release of glutathione under treatment with the antidotes DMSA and NAC.


Subject(s)
Antidotes/chemistry , Chromatography, Liquid/methods , Mass Spectrometry/methods , Mercury/pharmacokinetics , Methylmercury Compounds/pharmacokinetics , Adult , Female , Humans , Inactivation, Metabolic , Male , Mercury/blood , Methylmercury Compounds/blood , Models, Biological
7.
Electrophoresis ; 29(12): 2731-7, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18512677

ABSTRACT

CE was coupled to inductively coupled plasma MS (ICP-MS) and ESI-MS to identify and quantify the arsenic species arsenobetaine (AsB), arsenite (As(III)), arsenate (As(V)), and dimethylarsinic acid (DMA). A GC-flame ionization detector (FID)-based German standard method and ICP-MS were used for validation of the data obtained for arsenobetaine and total arsenic, respectively. LODs obtained with the CE-ESI-TOF-MS method were 1.0x10(-7) M for AsB, 5.0x10(-7) M for DMA, and 1.0x10(-6) M for As(III) and As(V). For the CE-ICP-MS method, LODs were 8.5x10(-8) M for AsB, 9.5x10(-8) M for DMA, 9.3x10(-8) M for As(III), and 6.2x10(-8) M for As(V). While CE-ICP-MS provided high sensitivity and better reproducibility for quantitative measurements, CE-ESI-MS with a TOF mass analyzer proved to be valuable for species identification. With this setup, fish samples were prepared and analyzed and the obtained data were successfully validated with the independent methods.


Subject(s)
Arsenicals/analysis , Fishes , Animals , Arsenates/analysis , Arsenites/analysis , Cacodylic Acid/analysis , Electrophoresis, Capillary , Mass Spectrometry/methods
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