Accumulation of Zearalenone in Herbage of Winter Pasture Situated in West Poland

The importance of winter pastures in beef production in Europe has been growing steadily. In Poland, especially in its western part, there are already farms which utilise pasture swards during late autumn and winter. The major problem, however, is the quality of forage ingested by animals as it tends to deteriorate with the passage of the vegetation season with danger of accumulation of various mycotoxins (Laser et al., 2003) of which the most important is zearalenone (ZEA)

Demonstration of an exposed-core fiber platform for two-photon rubidium spectroscopy

We demonstrate a promising fiber architecture for generating strong photon-photon interactions. Exposed-core silica optical fibers possess low-loss guidance between 400 and 1700 nm crucial for quantum-logic applications. The potential of this fiber is demonstrated by exciting a two-photon transition within a rubidium vapor using an exposed-core silica optical fiber. Transit-time broadened spectral features enable measurement of the evanescent-field scale length of (120 +/- 20) nm which shows excellent agreement with the characteristics of the modeled fiber mode (118 +/- 2) nm. We observe a two-photon absorption coefficient of 8.3 cm(-1) for one optical mode in response to a transmitted power of 1.3mW in the second mode. A clear pathway to an exposed-core fiber exhibiting substantial absorption mediated by a single photon is identified

Visualizing Interactions along the Escherichia coli Twin-Arginine Translocation Pathway Using Protein Fragment Complementation

The twin-arginine translocation (Tat) pathway is well known for its ability to export fully folded substrate proteins out of the cytoplasm of Gram-negative and Gram-positive bacteria. Studies of this mechanism in Escherichia coli have identified numerous transient protein-protein interactions that guide export-competent proteins through the Tat pathway. To visualize these interactions, we have adapted bimolecular fluorescence complementation (BiFC) to detect protein-protein interactions along the Tat pathway of living cells. Fragments of the yellow fluorescent protein (YFP) were fused to soluble and transmembrane factors that participate in the translocation process including Tat substrates, Tat-specific proofreading chaperones and the integral membrane proteins TatABC that form the translocase. Fluorescence analysis of these YFP chimeras revealed a wide range of interactions such as the one between the Tat substrate dimethyl sulfoxide reductase (DmsA) and its dedicated proofreading chaperone DmsD. In addition, BiFC analysis illuminated homo- and hetero-oligomeric complexes of the TatA, TatB and TatC integral membrane proteins that were consistent with the current model of translocase assembly. In the case of TatBC assemblies, we provide the first evidence that these complexes are co-localized at the cell poles. Finally, we used this BiFC approach to capture interactions between the putative Tat receptor complex formed by TatBC and the DmsA substrate or its dedicated chaperone DmsD. Our results demonstrate that BiFC is a powerful approach for studying cytoplasmic and inner membrane interactions underlying bacterial secretory pathways

Scale Loss and Survival in Smolts of Atlantic Salmon (Salmo salar) after Turbine Passage

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Air-clad holmium-doped silica fibre laser

D. G. Lancaster, D. J. Ottaway, P. C. Henry, R. Kostecki, T. M. Monr

Fabrication of suspended and exposed core silica fibres for sensing applications

We report on the fabrication of both enclosed and exposed suspended-core silica microstructured optical fibres. Both the fibre loss and environmental stability are characterised when exposed to some typical sensing and storage environments.Roman Kostecki, Erik P. Schartner, Heike Ebendorff-Heidepriem, Peter C. Henry, and Tanya M. Monr