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We are presenting a combination of two measurement methods for simultaneous generation of optical and electrical signals out of one gasochromic film. For this purpose we combined the UV–vis spectroscopy with the contact potential difference (CPD) measurement. To demonstrate the advantages of this combined measurement we chose a well-known gasochromic system. For testing the benefits and limitations of the concept, we used a phenol red based film with known sensitivity to CO 2 . Getting in contact with CO 2 the phenol red based sensitive layer shows changes in absorption spectra and in contact potential difference (CPD). Due to the combination of both measurement techniques the influence of temperature and humidity, which is always a challenge in gas detection, can be identified and eliminated. We see different signal behaviour of the two measurement methods at humidity and temperature changes. In dry conditions the optical signal response towards CO 2 is reduced, whereas the electrical signal is increased. Whereas the optical signal response is strongly dependent on the temperature, the electrical signal seems to be independent. These reactions look promising for future gas sensor applications in the field of gasochromic sensor dye evaluation. [ABSTRACT FROM AUTHOR]

Introduction: Lung carcinoids comprise a heterogeneous group of neuroendocrine tumors. Only few parameters have been identified that correlated with poor disease outcome, including 11q22-q25 deletions. New biomarkers are required to further improve diagnosis and prediction of prognosis. Aim(s): To identify differentially expressed genes between carcinoids with a favorable and poor outcome using high resolution gene-expression profiling, and to test their value as prognostic markers. Materials and methods: mRNA of five tumors with a favorable (>5yr survival) and five with a poor (distant metastasis / deceased) disease outcome was labeled and hybridized to 4x44k Agilent arrays, with a human pool expressing 70-80% of genes as a control. Results were validated by qRT-PCR and immunohistochemistry on an independent series of lung carcinoids. Results: Expression profiling revealed amongst others overexpression of the RET oncogene and repression of the homeobox gene OTP and CD44 in the poor prognosis group. In 54 frozen cases, low CD44 (p<0.0001) and OTP (p=0.0013), and high RET (p=0.0035) expression were significantly associated with decreased 15-year survival, outperforming WHO classification. Downregulation of CD44 and OTP expression was confirmed in tumors with a poor prognosis by immunohistochemistry. Conclusion: High resolution expression profiling unmasked new lung carcinoid candidate genes, of which CD44, OTP, and RET efficiently predict poor outcome. [ABSTRACT FROM AUTHOR]

• Combination of gasochromic dye with highly porous silica supraparticles. • Fully integrated sensor system: from the particle synthesis over electronics and a 3D printed diffusion chamber. • Sensitive detection of small and slowly rising CO concentrations (<< 20 ppm CO). • Reliable detection of smoldering and open fires , with wood as well as plastic compositions. • Competitive to commercially available smoke detectors. For early fire detection, the measurement of low and small rising concentrations of the fire typical gas carbon monoxide (CO) is essential. The approach presented herein integrates a highly sensitive colorimetric material into a low cost gas sensor system. The gas sensitive color dye is hosted by silica nanoparticle based supraparticles and then processed to a so-called gas sensor stripe. Changes in the CO concentration enable a change of the sensor stripes color, which is easily detectable as a change of the light that is reflected by the stripe. A diffusion chamber protects the gas sensitive film against harmful environmental influences and interfering light. The capability of the gas sensor system is demonstrated in lab as well as real fire tests. In case of the latter, standardized real fire tests are conducted, as well as realistic mixtures of plastics and wood are smoldered. The developed sensors react in real time to the slowly rising CO concentration during the test fires. Even small amounts of CO (<20 ppm) are reliably detectable. [ABSTRACT FROM AUTHOR]