Numerous factors including ultraviolet (UV) radiation and growth factors regulate the specific function of epidermal melanocytes. A recently discovered epidermal growth factor is sAPP, the soluble N-terminal ectodomain of the beta-amyloid precursor protein (APP). Using whole mount preparations of isolated human epidermis, we detected a small population of basal cells, which expressed exceptionally high levels of APP. These cells were identified as melanocytes, which, similar to keratinocytes and neuronal cells, expressed the three APP isoforms 695, 751, and 770. They differed in their expression pattern from that of neuronal cells by expressing only low levels of APP 695. Melanocytes and melanoma cells in vitro released, in addition to keratinocytes, large quantities of sAPP. Because of its growth factor function, we studied possible effects of sAPP on melanocytes. Recombinant sAPP strongly increased lamellipodia activity at dendritic tips, an effect that coincided with increased release of melanin particles. Our observations point to the possible use of APP as an immunocytochemical marker for melanocytes. They suggest that sAPP derived from keratinocytes and/or melanocytes belongs to a family of factors operating in the paracrine and/or autocrine regulation of melanocyte function.

Abstract. This article gives exact general conditions for the existence of an interior optimum growth rate for population in the neoclassical two-generations-overlapping model.In an economy where high (low) growth rates of population lead to a growth path which is efficient (inefficient) there always exists an interior optimum growth rate for population.In all other cases there exists no interior optimum. The Serendipity Theorem, however, does in general not hold in an economy with government debt. Moreover, the growth rate for population which leads an economy with debt to a golden rule allocation can never be optimal.

Gemäß dem Stufenplan Digitales Planen und Bauen des Bundesministeriums für Verkehr und digitale Infrastruktur (BMVI) ist ab 2020 die ganzheitliche Anwendung von Building Information Modeling (BIM) für Projekte im Infrastrukturbereich vorgesehen. Ansätze und Strategien zum Einsatz von BIM in Betrieb und Erhaltung von Brückenbauwerken liegen nur begrenzt vor. Das Ziel des Projekts ist es, die Möglichkeiten zur Erstellung von BIM‐fähigen As‐Built‐Modellen für Bestandsbrücken an einem Bauwerk zu untersuchen, anzuwenden und Empfehlungen zur Nutzung dieser Modelle in der Betriebsphase zu geben. Es wurden zwei Bauwerksmodelle anhand der Punktwolke eines Laserscans und der konventionellen Modellierung auf Grundlage von Bestandsunterlagen erstellt. Der geometrische Abgleich beider Modelle zeigt die Unterschiede von Plan‐ und Ist‐Zustand der Bestandsbrücke auf. Die Anwendungsbereiche der verschiedenen Modelle und der Aufwand zur Erstellung der Modelle werden erläutert.

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