230 research outputs found

    Development of an effective outsourcing strategy for toxicological studies in the chemical industry

    Full text link
    The chemical industry has been put under considerable time pressure by the European Community Regulation REACH (Registration, Evaluation, and Authorization of Chemicals). The work outlined here has been developed at the BASF SE’s Experimental Toxicology and Ecology Unit with the objective of promoting a faster reaction to the testing demand generated by the new legislation. A considerable increase in forecasted demand for tests has created the necessity to increase the Toxicology Unit’s outsourcing activities. The first goal was to optimize the selection and management process of Contract Research Organizations (CROs), so that toxicological studies can be performed with minimal risk while maximizing quality and cost advantage. A second objective was to develop performance measurement system in form of a balanced scorecard to evaluate contracting efficiency by monitoring major drivers in the outsourcing process to ensure the alignment between strategic objectives and actual performance.<br

    Multiplexed gas spectroscopy using tunable VCSELs

    Full text link
    Detection and identification of gas species using tunable laser diode laser absorption spectroscopy has been performed using vertical cavity surface emitting lasers (VCSEL). Two detection methods are compared: direct absorbance and wavelength modulation spectroscopy (WMS). In the first, the output of a DC-based laser is directly monitored to detect for any quench at the targeted specie wavelength. In the latter, the emission wavelength of the laser is modulated by applying a sinusoidal component on the drive current of frequency {omega}, and measuring the harmonics component (2{omega}) of the photo-detected current. This method shows a better sensitivity measured as signal to noise ratio, and is less susceptible to interference effects such as scattering or fouling. Gas detection was initially performed at room temperature and atmospheric conditions using VCSELs of emission wavelength 763 nm for oxygen and 1392 nm for water, scanning over a range of approximately 10 nm, sufficient to cover 5-10 gas specific absorption lines that enable identification and quantization of gas composition. The amplitude and frequency modulation parameters were optimized for each detected gas species, by performing two dimensional sweeps for both tuning current and either amplitude or frequency, respectively. We found that the highest detected signal is observed for a wavelength modulation amplitude equal to the width of the gas absorbance lines, in good agreement with theoretical calculations, and for modulation frequencies below the time response of the lasers (&lt;50KHz). In conclusion, we will discuss limit of detection studies and further implementation and packaging of VCSELs in diode arrays for continuous and simultaneous monitoring of multiple species in gaseous mixtures

    Chronische posttraumatische Schulterinstabilität

    Get PDF
    Chronic posttraumatic shoulder instability is characterized by trauma-associated, recurrent dislocations. Surgical treatment is indicated in most cases but it remains controversial how risk factors should be weighted to decide between arthroscopic Bankart repair (ABR), Latarjet or alternative procedures. Known risk factors for recurrence are patient age, hyperlaxity, sports profile and bone loss. Surgical techniques are discussed in detail. The ABR leads to high patient satisfaction and return to sports; however, in association with risk factors, recurrent dislocations are seen even several years later. Latarjet or bone block procedures lead to high patient satisfaction, sustainable stability as a revision procedure, but can also be primarily indicated for chronic instability depending on risk factors. Early complications are more frequent but of a minor nature in most cases. All techniques are known for a serious learning curve. If performed well, they do not seem to increase the risk of arthritis, which is most affected by the number of lifetime dislocations and higher energy trauma

    Offene Latarjet-Patte-Operation nach Walch : Tipps, Tricks und Komplikationsvermeidung

    Get PDF
    Walch hat die Latarjet-Patte-Operation in offener Technik unter Anwendung eines Subskapularis-Splits in den 1980er-Jahren modifiziert, standardisiert und über Jahrzehnte mit großem Erfolg bei über 3500 Patienten angewandt. In Langzeitnachuntersuchungen wurden Rezidivraten von 1–5 % bei hoher Patientenzufriedenheit im Subjective Shoulder Value (SSV > 90 %) dokumentiert [1, 2]. Diese Ergebnisse konnten in Zürich durch Gerber reproduziert werden [3]. Die Methode hat in mehreren Langzeitstudien den Beweis des Erreichens dauerhafter Stabilität (Langzeitstabilität nach mehr als 6 bis 10 Jahren) bei Risikopatienten erbracht [2, 3], besonders für Wettkampfsportler [4,5,6], junge Patienten [7, 8] und Patienten mit glenoidalem Knochenverlust [1, 9]. Bei korrekter Operationstechnik entsteht kein klinisch relevanter Beweglichkeitsverlust, und es besteht kein Zusammenhang mit der Entstehung oder Progression einer Instabilitätsarthrose [10]. In einer randomisierten kontrollierten Studie (RCT) zeigte sich eine signifikant niedrigere Reluxationsrate für die Latarjet-Stabilisierung bei jungen Männern unter 25 Jahren im Vergleich zur arthroskopischen Bankart-Operation [8]
    • …
    corecore