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  • Olaf Tietje
  • European Journal of Operational Research
  • 2005
In scenario analyses, in which experts have rated the consistency of impact factor levels, all scenarios are defined by vectors of these impact factors. Because the identification of scenarios out of all combinatorial scenarios was time consuming and inefficient, three new approaches were developed: Local efficiency as a goal function of a simple(More)
Pulmonary tuberculosis may alter volatile organic compounds (VOCs) in breath because Mycobacteria and oxidative stress resulting from Mycobacterial infection both generate distinctive VOCs. The objective of this study was to determine if breath VOCs contain biomarkers of active pulmonary tuberculosis. Head space VOCs from cultured Mycobacterium tuberculosis(More)
We evaluated a breath test for volatile organic compounds (VOCs) as a predictor of breast cancer. Breath VOCs were assayed in 51 asymptomatic women with abnormal mammograms and biopsy-proven breast cancer, and 42 age-matched healthy women. A fuzzy logic model predicted breast cancer with accuracy superior to previously reported findings. Following random(More)
BACKGROUND Early detection of melanoma is of great importance to reduce mortality. Discovering new melanoma biomarkers would improve early detection and diagnosis. Here, we present a novel approach to detect volatile compounds from skin. METHODS AND FINDINGS We used Head Space Solid Phase Micro-Extraction (HS-SPME) and gas chromatography/mass spectrometry(More)
The goal of this research work was to assist consumers in considering environmental aspects of food consumption. A simplified, modular LCA approach has been used to evaluate the impacts from the consumers' point of view. Comparative LCA's have been calculated for five single aspects of decisions: type of agricultural practice, origin, packaging material,(More)
In order for soil resources to be sustainably managed, it is necessary to have reliable, valid data on the spatial distribution of their environmental impact. However, in practice, one often has to cope with spatial interpolation achieved from few data that show a skewed distribution and uncertain information about soil contamination. We present a case(More)
We report on the search for low molecular weight molecules-possibly accumulated in the bloodstream and body-in the exhaled breath of uremic patients with kidney malfunction. We performed non-invasive analysis of the breath gas of 96 patients shortly before and several times after kidney transplantation using proton-transfer-reaction mass spectrometry(More)
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