A new GC-MS method for characterization and quantification of phytosterol oxidation products was developed.Applicability of this method was tested by characterizing sitostanol oxides formed in bulk and then quantifying selected oxides in purified rapeseed oil and tripalmitin matrices in which the complex matrix made oxide analysis difficult. In bulk, nine different sitostanol oxides were characterized, including epimers of 7-and 15-hydroxysitostanol and 6-and 7-ketositostanol. In both lipid matrices, the amounts of sitostanol oxides generated in thermo-oxidation were very low. According to statistical analyses, depending on the oxide, the GC-MS results were the same or slightly higher than those quantified by the more common GC-FID method. Thus, GC-MS provides a powerful alternative for characterization and quantification of phytostanol oxides found in low amounts in complex matrices and is a promising method for future phytosterol oxide studies.

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KeyWords Gas chromatographyBrominated flame retardants Sediment samples Soxhlet extraction Pressurised ho water extraction SummaryA pressurised, hot-water extraction (PHWE) method was developed for brominated flame-retardants in sediments. The effect of extraction time, temperature and pressure on PHWE recovery was investigated, together with solid-phase collection parameters (trapping material, length of trapping column, eluent composition). The concentrated extracts were analysed by GC-MS. PHWE recoveries were compared with those obtained by conventional Soxhlet-extraction. In general, recoveries were much higher with PHWE than with Soxhlet.

According to the received view, Marxian (ideology) critique and Foucaultian (genealogical) critique constitute two divergent approaches of critical theory that have remarkably different goals and little in common. In this article, however, we identify a guiding thread that connects the Marxian and Foucaultian traditions and motivates a distinctive approach within critical theory we call the ‘critique of constitution’. The problem of restricted consciousness, we show, is the core problem in common between Michel Foucault's critical history of thought and Georg Lukács's theory of reification which underlies the tradition of Western Marxism and Frankfurt School critical theory. The problem concerns the limits of intelligibility and, by the same token, the apparent inevitability of the given social ontology. Our sense of what is possible depends on what we are able to think. But we know from the history of sciences that the limits of intelligibility change, thereby also altering our sense of what is possible. This becomes a political problem in connection with the intelligibility of social reality, because our restricted consciousness limits the alternatives we can so much as consider and seek to bring about. The critique of constitution, then, aims to expand the scope of possibility by revealing the contingent formation of the given limits of intelligibility. We argue that this is the paramount political task for Foucault and Lukács alike, other important differences notwithstanding.