Performance evaluation of the PET sub-systems of two PET/CT imagers according to NEMA standard NU 2-2001.

Unlabelled: Performance and image quality of PET scanners are mainly determined by the choice of the detector material and the realised design of the scanner. The aim of this study was to measure the PET performance characteristics of two state-of-the-art PET/CT Systems.

Methods: Performance measurements following the NEMA NU 2-2001 standard were performed on a GSO-based system and on a system with LSO detectors.

Novel approach to identifying supersaturated metastable ambient aerosol particles.

Atomic force microscopy (AFM) was used to determine the shape of fine and ultrafine ambient aerosol particles with sizes between 25 and 700 nm after soft landing on a solid substrate. The particles were collected in summer during daytime at a relative humidity around 50%. To avoid kinetically induced deformation, as previously observed using high-velocity sampling in impactors, the particles were collected on pore filters at very low face velocities (on the order of 10 cm/s).

Micropipet-based pico force transducer: in depth analysis and experimental verification.

Measurements of forces in the piconewton range are very important for the study of molecular adhesion and mechanics. Recently, a micropipet-based force transducer for this type of experiment was presented (E. Evans, K.

Biliary mucin secreted by cultured human gallbladder epithelial cells carries the epitope of CA 19-9.

Serum CA 19-9 is increased in patients with different gastrointestinal malignancies. Unfortunately, CA 19-9 is also detected in high concentrations in normal bile causing unspecific serum elevations during inflammatory disease of the biliary tract and cholestasis. In order to identify the source of CA 19-9 in bile, the capacity of cultured human gallbladder epithelial cells (HGBEC) to secrete CA 19-9 was investigated.