Quantum space-times in the year 2002

We review certain emergent notions on the nature of space-time from noncommutative geometry and their radical implications. These ideas of space-time are suggested from developments in fuzzy physics, string theory, and deformation quantization. The review focuses on the ideas coming from fuzzy physics. We find models of quantum space-time like fuzzy S ⁴ on which states cannot be localized, but which fluctuate into other manifolds like CP³. New uncertainty principles concerning such lack of localizability on quantum space-times are formulated. Such investigations show the possibility of formulating and answering questions like the probability of finding a point of a quantum manifold in a state localized on another one. Additional striking possibilities indicated by these developments is the (generic) failure of CPT theorem and the conventional spin-statistics connection. They even suggest that Planck’s ‘constant’ may not be a constant, but an operator which does not commute with all observables. All these novel possibilities arise within the rules of conventional quantum physics, and with no serious input from gravity physics.     

Prediction of the Behaviour of Biomass Ash in Fluidized Bed Combustors and Gasifiers

Two types of agricultural residues (wheat straw and olive residue) in untreated and pretreated (fractionation, leaching) form were tested as concerns their ash melting behaviour during fluidized bed combustion and gasification by means of thermal analysis techniques. The techniques applied included DSC, simultaneous DSC/TG and TG-MS for the determination of low-temperature ash melts and losses caused by the volatilization of alkali material. In combination with ash elemental analyses on the materials, the applied techniques proved to offer valuable information for prediction of the ash behaviour in fluidized bed reactors. This revised version was published online in August 2006 with corrections to the Cover Date.     

INFLUENCE OF GLASS CULLET IN CEMENT PASTES

1. Introduction The necessity for glass cullet recycling is becoming more and more imperative not only due to the general need of solid waste volume reduction, but also due to the strict European legislation, which defines the levels of re- cycling packaging materials including glass cullet. Accord- ing to valid estimates, the total consumption of packaging materials was 58 million tones for 1997 in Europe, 25% of which comprised glass. The present target for recycling is a minimum of 25% for…     

Investigation of the quantitative properties of the quadrupole orthogonal acceleration time-of-flight mass spectrometer with electrospray ionisation using 3,4-methylenedioxymethamphetamine

This paper describes the investigation of the potential of a quadrupole orthogonal acceleration time-of-flight mass spectrometer (Q-TOF) equipped with an atmospheric pressure ionisation interface for quantitative measurements of small molecules separated by reversed phase liquid chromatography. To this end, the detection limits and linear dynamic range in particular were studied in an LC/MS/MS experiment using 3,4-methylenedioxymethamphetamine standards and 3,4-methylenedioxyethylamphetamine for internal standardisation. In a second phase, the experiment was repeated with real biological extracts (whole blood, serum, and vitreous humour). A calibration for 3,4-methylenedioxymethamphetamine and its metabolite 3,4-methylenedioxyamphetamine was prepared in each of these matrices again using 3,4-methylenedioxyethylamphetamine as internal standard. The resulting quantitative data were compared with those obtained by liquid chromatography with fluorescence detection for the same extracts. The Q-TOF results revealed excellent sensitivity and a linear dynamic range of nearly four decades (2-10 000 pg on-column, r(2) = 0.9998, 1/x weighting). Furthermore, all the calibration curves prepared in biological material were superimposable, LC/MS/MS and LC-fluorescence, and the quantitative results for actual samples compared very favourably. It was concluded that the Q-TOF achieves a linear dynamic range for quantitative LC/MS/MS work exceeding that of fluorescence detection and at much better absolute sensitivity. Copyright 1999 John Wiley & Sons, Ltd.     

Effects of Sideritis euboea (Lamiaceae) aqueous extract on IL-6, OPG and RANKL secretion by osteoblasts

The water extract obtained from the aerial parts of Sideritis euboea (Lamiaceae), which is known in Greece as 'mountain tea', was investigated by determining the in vitro effect of this extract on the IL-6, OPG and RANKL secretion by osteoblasts, three important molecules in osteoblast-osteoclast interplay. The results showed that this extract reduced significantly the secretion of IL-6 by KS-483 osteoblasts, while it also suppressed RANKL secretion, with both effects being dose-dependent and more potent at the higher concentrations tested (50, 100 microg/mL). We further determined the chemical profile of the extract by applying an analytical U-HPLC-DAD-ESI-MS/MS method using the high resolution hybrid LTQ-Orbitrap Discovery spectrometer. An ESI source in negative mode was employed. The analysis indicated that the water extract of S. euboea is rich in flavonoid glycosides, and phenylpropanoid glycosides.