The clinical data, diagnostic procedures and survival are reported in 19 cases diagnosed as malignant peritoneal mesothelioma. All patients were men and 74% had an occupational exposure to asbestos, whereas in 26% no information about asbestos exposure was available. The median interval between asbestos exposure and the diagnosis appeared to be 44.7 years (range 18–49 years). The most common presenting symptoms were abdominal pain, weight loss and dysphagia. Most patients presented with a large amount of ascites. In the majority of patients no therapy except pain relief was given and the median survival from the time of diagnosis was 6 months (range: 0–29 months). Some patients received surgery or chemotherapy, which however did not prolong survival. Only in 2 patients survival exceeded 1 year, although these patients did not receive therapy. The autopsy findings of some patients showed that there were positive abdominal lymph nodes in 2 of them, while in no case positive thoracic lymph nodes were found. The relative short survival period from the time of the first diagnosis in contrast to malignant pleural mesotheliomas is probably the reason for the absence of distant metastases. In this series only in a minority of patients cytology of the ascites was positive and often a laparotomy had to be done. Since cytologic specimens are often negative, we suggest that in patients suspected of a malignant peritoneal mesothelioma, laparoscopy with directed biopsies is the diagnostic procedure of first choice.

We employ photoluminescence (PL) spectroscopy on individual nanoscale aggregates of the conjugated polymer poly(3-hexylthiophene), P3HT, at room temperature (RT) and at low temperature (LT) (1.5 K), to unravel different levels of structural and electronic disorder within P3HT nanoparticles. The aggregates are prepared by self-assembly of the block copolymer P3HT- block -poly(ethylene glycol) (P3HT- b -PEG) into micelles, with the P3HT aggregates constituting the micelles’ core. Irrespective of temperature, we find from the intensity ratio between the 0–1 and 0–0 peaks in the PL spectra that the P3HT aggregates are of H-type nature, as expected from π-stacked conjugated thiophene backbones. Moreover, the distributions of the PL peak ratios demonstrate a large variation of disorder between micelles (inter-aggregate disorder) and within individual aggregates (intra-aggregate disorder). Upon cooling from RT to LT, the PL spectra red-shift by 550 cm –1 , and the energy of the (effective) carbon-bond stretch mode is reduced by 100 cm –1 . These spectral changes indicate that the P3HT backbone in the P3HT- b -PEG copolymer does not fully planarize before aggregation at RT and that upon cooling, partial planarization occurs. This intra-chain torsional disorder is ultimately responsible for the intra- and inter-aggregate disorder. These findings are supported by temperature-dependent absorption spectra on thin P3HT films. The interplay between intra-chain, intra-aggregate, and inter-aggregate disorder is key for the bulk photophysical properties of nanoparticles based on conjugated polymers, for example, in hierarchical (super-) structures. Ultimately, these properties determine the usefulness of such structures in hybrid organic–inorganic materials, for example, in (bio-)sensing and optoelectronics applications.

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