Publications by authors named "S M Witte"

Working memory is crucial for daily life and is often impaired in neuropsychiatric conditions. Attempts to enhance it using transcranial direct current stimulation (tDCS) have shown mixed results, possibly due to large inter-individual variability. This study assessed whether baseline regional brain volume was associated with working memory performance following tDCS.

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In eukaryotic post-replicative mismatch repair, MutS homolog complexes detect mismatches and in the major eukaryotic pathway, recruit Mlh1-Pms1/MLH1-PMS2 (yeast/human) complexes, which nick the newly replicated DNA strand upon activation by the replication processivity clamp, PCNA. This incision enables mismatch removal and DNA repair. Beyond its endonuclease role, Mlh1-Pms1/MLH1-PMS2 also has ATPase activity, which genetic studies suggest is essential for mismatch repair, although its precise regulatory role on DNA remains unclear.

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Strain-induced variation of the refractive index is the main mechanism of strain detection in photoacoustic experiments. However, weak strain-optic coupling in many materials limits the application of photoacoustics as an imaging tool. A straightforward deposition of a transparent thin film as a top layer has previously been shown to provide signal enhancement due to elastic boundary effects.

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Many DNA metabolic pathways, including DNA repair, require the transmission of signals across long stretches of DNA or between DNA molecules. Solutions to this signaling challenge involve various mechanisms: protein factors can travel between these sites, loop DNA between sites, or form oligomers that bridge the spatial gaps. This review provides an overview of how these paradigms have been used to explain DNA mismatch repair, which involves several steps that require action-at-a-distance.

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Digital holographic microscopy retrieves amplitude and phase information of an image which allows us to computationally correct for imperfections in the imaging optics. However, digital holographic microscopy is an interferometric technique that is inherently sensitive to undesired phase variations between object and reference beam. These phase variations lower the fringe contrast if they are integrated over a finite exposure time which leads to a reduced amplitude of the retrieved image.

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