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The two most important measurement categories in production are temperature and load. Therefore commercial sensors are applied in machinery as near as possible to the working parts. For a cost efficient production the integration of sensor elements directly on top of the surface in the heavily loaded regions is essential to get the real temperature and load distributions during the production process. Therefore a new multifunctional thin film sensor system is in development. This multilayer system combines thermoresistive sensor structures with piezoresistive ones and exists out of wear resistant carbon based layers (Bewilogua and Hofmann, Surf Coat Technol 242:214-225, 2014; Biehl et al. Thin Solid Films 515:1171-1175, 2006; Biehl et al. Microsystem Technologies, Springer, 2010; Biehl et al. Microsystem Technologies, Springer, 2014; Robertson, Daim Relat Mater 12:79-84, 2003). The sensor data will lead to a deeper process understanding, to optimization of simulation tools, to reduction of rejects and to an improvement of flexibility in production. [ABSTRACT FROM AUTHOR]

Thin film sensor systems based on hydrogenated carbon have the advantage to combine two very important characteristics in order to be used in measurement engineering: Firstly, the sensory layer demonstrates piezoresistive behavior and secondly its good properties related to hardness and wear resistance lead in a tribologically stable system. Therefore, the thin film sensor systems can be applied into the main distribution of force within machine parts or used for universal interchangeable sensor systems, e.g. sensory washers. In this article the deposition of a self-contained thin film sensor system on a large technical component (spindle shaft) is shown. The spindle shaft with a length of 480 mm and an outer diameter of 90 mm is part of a belt driven machining spindle for planing machines in woodworking industries. In order to establish a measurement system, which allows monitoring the clamping force of the tool holder and the imbalance of the mounted tool, the thin film sensor system was directly applied to the front surface of the spindle shaft. For this application a novel self-contained thin film sensor system was developed, which consists of an alumina layer for electrical isolation, a chromium layer to establish internal sensor electrodes, a piezoresistive hydrogenated carbon layer (1 μm) and a second covering wear resistance and insulation layer (silicon and oxygen modified carbon layer). The piezoresistive sensor layer and the top layer are part of the diamond like carbon layer family (Robertson, Diam Relat Mater 12:79-84, ; Bewilogua et al. DLC based coatings for tribological applications, pp. 67-75, ; Biehl et al. Thin Solid Films 515(3):1171-1175, , Novel measurement and monitoring system for forming processes based on piezoresistive thin film systems. Springer Verlag, pp. 879-883, ). [ABSTRACT FROM AUTHOR]

Staphylococcal α-toxin is an archetypal killer protein that homo-oligomerizes in target cells to create small transmembrane pores. The membrane-perforating β-barrel motif is a conserved attack element of cytolysins of Gram-positive and Gram-negative bacteria. Following the recognition that nucleated cells can survive membrane permeabilization, a profile of abundant transcripts was obtained in transiently perforated keratinocytes. Several immediate early genes were found to be upregulated, reminiscent of the cellular response to growth factors. Cell cycle analyses revealed doubling of S + G2/M phase cells 26 h post toxin treatment. Determination of cell counts uncovered that after an initial drop, numbers increased to exceed the controls after 2 days. A non-lytic α-toxin mutant remained without effect. The α-toxin pore is too small to allow egress of cytosolic growth factors, and evidence was instead obtained for growth signalling via the epidermal growth factor receptor (EGFR). Inhibition of the EGFR or of EGFR-proligand-processing blocked the mitogenic effect of α-toxin. Western blots with phospho-specific antibodies revealed activation of the EGFR, and of the adapter protein Shc. Immediate early response and proliferation upon transient plasma membrane pore formation by bacterial toxins may represent a novel facet of the complex interaction between pathogen and host. [ABSTRACT FROM AUTHOR]