Publications by authors named "Alexander Grupp"

In this work, we investigate the exciton dissociation dynamics occurring at the donor:acceptor interface in organic and hybrid blends employed in the realization of photovoltaic cells. Fundamental differences in the charge separation process are studied with the organic semiconductor polymer poly(3-hexylthiophene) (P3HT) and either [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) or titanium dioxide (TiO) acting as the acceptor. By using ultrafast broad-band transient absorption spectroscopy with few-fs temporal resolution, we observe that in both cases the incoherent formation of free charges dominates the charge generation process.

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Background: Local defense mechanisms are important for the integrity of the peritoneum, but few details are known about the expression patterns of antimicrobial proteins such as human defensin in normal and damaged peritoneum.

Methods: Part A: The expression of different defensins in normal (n = 12), inflamed (n = 5), and metastatic peritoneum (n = 4) and in cultured human peritoneal mesothelial cells was analyzed using mRNA and immunohistochemistry. Part B: Using immunohistochemistry the expression of different defensins was analyzed in different subgroups: healthy controls (n = 25), patients with chronic appendicitis (n = 25) or acute appendicitis (n = 10), and end-stage renal disease patients (n = 25, with 15 on peritoneal dialysis).

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