Publications by authors named "Christoph Baum"

Unlabelled: is the thermophilic acetogenic bacterium with the highest temperature optimum (66°C) and with high growth rates on hydrogen (H) plus carbon dioxide (CO). The bioenergetic model suggests that its redox and energy metabolism depends on energy-converting hydrogenases (Ech). Its genome encodes two Echs, Ech1 and Ech2, as sole coupling sites for energy conservation during growth on H + CO.

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DNA uptake is widespread among microorganisms and considered a strategy for rapid adaptation to new conditions. While both DNA uptake and adaptation are referred to in the context of natural environments, they are often studied in laboratories under defined conditions. For example, a strain of the thermophile Thermoanaerobacter kivui had been adapted to growth on high concentrations of carbon monoxide (CO).

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The healing of neuronal injuries is still an unachieved goal. Medicine-based therapies can only extend the survival of patients, but not finally lead to a healing process. Currently, a variety of stem cell-based tissue engineering developments are the subject of many research projects to bridge this gap.

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Microalgae are not able to produce cobamides (Cbas, B12 vitamers) de novo. Hence, the production of catalytically active Cba-containing methionine synthase (MetH), which is present in selected representatives, is dependent on the availability of exogenous B12 vitamers. Preferences in the utilization of exogenous Cbas equipped with either adenine or 5,6-dimethylbenzimidazole as lower base have been reported for some microalgae.

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Acetogenic bacteria have gained much attraction in recent years as they can produce different biofuels and biochemicals from H plus CO or even CO alone, therefore opening a promising alternative route for the production of biofuels from renewable sources compared to existing sugar-based routes. However, CO metabolism still raises questions concerning the biochemistry and bioenergetics in many acetogens. In this study, we focused on the two acetogenic bacteria Acetobacterium woodii and Thermoanaerobacter kivui which, so far, are the only identified acetogens harbouring a H -dependent CO reductase and furthermore belong to different classes of 'Rnf'- and 'Ech-acetogens'.

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A reduced channel height in microfluidic Lab-on-a-Chip (LOC) devices enables a reduction in the required volume of sample and reagents. LOC devices are most often manufactured by microstructuring a planar substrate and subsequently sealing it with a cover film. However, shallow chip designs, made from polymers, are sensitive to channel deformation during the sealing of the microfluidic device.

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One of the main challenges in the diagnosis of infectious diseases is the need for rapid and accurate detection of the causative pathogen in any setting. Rapid diagnosis is key to avoiding the spread of the disease, to allow proper clinical decisions to be made in terms of patient treatment, and to mitigate the rise of drug-resistant pathogens. In the last decade, significant interest has been devoted to the development of point-of-care reverse transcription polymerase chain reaction (PCR) platforms for the detection of RNA-based viral pathogens.

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The present study evaluated a hull-volume definition strategy for the planning organ at risk volume (PRV) for the rectum in the planning of radiotherapy of prostate cancer. The bounding volumes of rectum contours of 1 to 5 CT scans were compared on the basis of the rectum coverage probabilities for 5 patients. In addition, IMRT treatment plans were optimized using the rectum hull PRV5 of 5 CTs and each of the conventional rectum contours PRV1.

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Background And Purpose: To evaluate an optimization approach where coverage probabilities are incorporated into the optimization of intensity modulated radiotherapy (IMRT) to overcome the problem of margin definition in the case of overlapping planning target volume and organs at risk.

Patients And Methods: IMRT plans were generated for three optimization approaches: based on a planning CT plus margin (A), on prostate and rectum contours from five pre-treatment CT plus margin (B), and on coverage probabilities (C). For approach (C), the probability of organ occupation was computed for each voxel from five pre-treatment CTs and the population distribution of systematic setup error and it was used as local weight in the costfunctions.

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Purpose: To evaluate the consequences of a planning volume definition based on multiple CTs and the application of off-line setup error correction for the treatment of prostate cancer with intensity-modulated radiotherapy (IMRT). Further, to compare various setup correction protocols (SCP) by their influence on the average dose distributions.

Materials And Methods: A planning target volume (PTV) consisting of the bounding volume of prostate contours of five CTs (CTV_hull) plus an additional margin of 5mm and a virtual Rectum_hull volume (the solid bounding volume of the five corresponding rectum contours) are used for treatment planning.

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