Eddy covariance measurements of net ecosystem exchange (NEE) of carbon dioxide and sensible and latent heat have operated since clear felling of a 50‐year old maritime pine stand in Les Landes, in Southwestern France. Turbulent fluxes from the closed‐path system are computed via different methodologies, including those recommended from EUROFLUX (Adv. Ecol. Res. 30 (2000) 113; Agric. Forest Meteorol. 107 (2001a, b) 43 and 71), and sensitivity analysis demonstrates the merit of post‐processing for accurate flux calculation. Footprint modeling, energy balance closure, and empirical modeling corroborate the eddy flux measurements, indicating best reliability in the daytime. The ecosystem, a net source of atmospheric CO2, is capable of fixing carbon during fair weather during any season due to the abundance of re‐growing species (mostly grass), formerly from the understorey. Annual carbon loss of 200–340 g m−2 depends on the period chosen, with inter‐annual variability evident during the 18‐month measurement period and apparently related to available light. Empirical models, with weekly photosynthetic parameters corresponding to seasonal vegetation and respiration depending on soil temperature, fit the data well and allow partitioning of annual NEE into GPP and TER components. Comparison with a similar nearby mature forest (Agric. Forest Meteorol. 108 (2001) 183) indicates that clear‐cutting reduces GPP by two thirds but TER by only one third, transforming a strong forest sink into a source of CO2. Likewise, the loss of 50% of evapotranspiration (by the trees) leads to increased temperatures and thus reduced net radiation (by one third), and a 50% increase in sensible heat loss by the clear cut.

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The chemical structure of 5-hydroxymethyl-2-furfural (HMF), its physicochemical properties and reactions that lead to the synthesis of HMF were discussed. Special attention was paid to HMF formation in food during processing. The potential applications of this compound in industry were described as well. Moreover, this review outlines the most important sources of HMF in human diet and estimates the potential daily intake of HMF by consumers. The known and suggested metabolic pathways, as well as the impact of HMF and its metabolites on human health are also discussed.

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This comprehensive review of sauces and salad dressings covers the literature over the last decade with respect to physical and chemical properties and the applications of these products. As such, texturizing and structural systems (especially hydrocolloids) are described in detail and the application of polysaccharide thickeners as texture providers is described. Microbiological aspects of sauces are covered with relevant sections discussing the factors affecting microbiological activity and microbial spoilage and/or enhancement of a range of sauces. In addition, the use of carbohydrates and proteins as emulsifiers in many sauces is described. Quality aspects are given prominence in this review with sections being devoted to rheological and textural properties, chromatographic approaches and sensory aspects. Healthy sauces such as those having low sodium, reduced fat and cholesterol or containing inulin or microcrystalline cellulose are reviewed. Finally, for various sections the trends of the main findings as well as suggestions for future research are presented.

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The PO glycoprotein, the major protein of peripheral nerve myelin, is a hydrophobic glycoprotein which can be isolated in soluble and insoluble forms from rabbit sciatic nerve myelin following extensive defatting and mid acidic extraction. The PO glycoprotein was localized exclusively in peripheral nervous system (PNS) myelin of sciatic nerve and rootlets by the immunofluorescent technique using goat anti-PO serum which showed a single precipitin band in double diffusion and did not cross-react with the myelin basic protein or P2 protein. Central nervous system (CNS) myelin from brain and spinal cord was negative by the immunofluorescent procedure. The major glycoprotein bands in PNS myelin, in addition to the PO glycoprotein at 28K, exist at 23K and 19K, as shown by gel electrophoresis in dodecyl sulfate. These glycoproteins, isolated by gel filtration in 2% dodecyl sulfate, show identity to the PO glycoprotein in their monosaccharide profile and overlapping tryptic peptides on peptide mapping. We conclude that both the 23K and 19K glycoproteins are derived from the PO glycoprotein by in situ proteolysis; the 23K glycoprotein has the identical amino terminal sequence. The 19K glycoprotein, beginning with amino-terminal methionine, is identical with the TPO glycoprotein, shown previously to originate from tryptic hydrolysis of the PO glycoprotein in isolated myelin. A tryptic glycopeptide containing 27 amino acids was isolated from the PO glycoprotein and sequenced. It contained a relatively high proportion of aspartic acid (four residues) and glutamic acid (two residues), thus exhibiting a high negative charge. We conclude that the total carbohydrate of the PO, 23K, and 19K glycoproteins does indeed exist as a single nonasaccharide moiety linked through N-acetylglucosamine to Asp-14 of the glycopeptide in a N-glycosidic linkage. These results further support the role of the PO glycoprotein as a typical amphipathic membrane protein.