8 research outputs found
Antithrombotic Effects of Pyridinium Compounds Formed from Trigonelline upon Coffee Roasting
Coffee
may exert a preventive effect on arterial thrombosis. Trigonelline
is one of the most abundant compounds in coffee that undergoes pyrolysis
upon roasting of coffee beans. The aim of the present study was to
identify pyridinium compounds formed upon trigonelline pyrolysis and
coffee roasting and to investigate the effect of three of them, i.e.,
1-methylpyridine and 1,3- and 1,4-dimethylpyridine, on experimentally
induced arterial thrombosis in rats. 1,3- and 1,4-dimethylpyridine
but not 1-methylpyridine inhibited arterial thrombus formation. 1,3-Dimethylpyridine
inhibited platelet aggregation and reduced fibrin formation in platelet-rich
plasma, whereas 1,4-dimethylpyridine increased the plasma level of
6-keto-PGF<sub>1α</sub>. 1,4-Dimethylpyridine slightly increased
rat tissue plasminogen activator plasma activity. In summary, we demonstrated
that pyridinium compounds display mild antithrombotic properties due
to stimulation by prostacyclin release (1,4-dimethylpyridine) and
inhibition of platelet aggregation (1,3-dimethylpyridine). Those pyridinium
compounds may, to some extent, be responsible for the beneficial effects
of coffee drinking
An innovative silicon photomultiplier digitizing camera for gamma-ray astronomy
The single-mirror small-size telescope (SST-1M) is one of the three proposed
designs for the small-size telescopes (SSTs) of the Cherenkov Telescope Array
(CTA) project. The SST-1M will be equipped with a 4 m-diameter segmented mirror
dish and an innovative fully digital camera based on silicon photo-multipliers
(SiPMs). Since the SST sub-array will consist of up to 70 telescopes, the
challenge is not only to build a telescope with excellent performance, but also
to design it so that its components can be commissioned, assembled and tested
by industry. In this paper we review the basic steps that led to the design
concepts for the SST-1M camera and the ongoing realization of the first
prototype, with focus on the innovative solutions adopted for the photodetector
plane and the readout and trigger parts of the camera. In addition, we report
on results of laboratory measurements on real scale elements that validate the
camera design and show that it is capable of matching the CTA requirements of
operating up to high-moon-light background conditions.Comment: 30 pages, 61 figure