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The aim of this study was to investigate whether Neoptyphodium spp. endophytes, fungal symbionts of cool-season grasses, can be selected to improve plant growth and seed yield of perennial ryegrass (Lolium perenne L.). Endophyte-infected (EI) and endophyte-free (EF) clones of 13 L. perenne genotypes, collected from native habitats with stressful environmental conditions, were evaluated in a field experiment for symbiotic effects on plant growth (herbage yield, reproductive tiller number), seed production, and seed quality parameters [1000-seed weight (TSW), germination] over 3 yr in an area with low rainfall (Halle, Germany). The results revealed high variability in endophyte effects on the investigated parameters. In seven genotypes, endophyte presence improved plant growth and seed production during the first harvest year. However, in four of these genotypes, endophyte effects were reversed in the following harvests. In the remaining six genotypes, endophyte infection reduced plant performance. The impact of the fungus on TSW was inconsistent, while seed germination was either improved or not affected by the endophyte. A positive endophyte effect was detectable for genotypes with low performance of EF clones, whereas genotypes with high-yield EF clones were not, or negatively, affected by the endophyte. Gcnotypes originating from sites exposed to flooding and periodic drought showed consistent negative endophyte effects on herbage yield and seed production. Since reduced shoot growth is a drought avoidance mechanism, further studies are needed to determine whether endophytes in these genotypes improve adaptation to drought, or represent a 'metabolic cost.' Our results indicate that some Neotyphodium endophytes have the potential to improve plant performance of L. perenne, but the selection of strains with consistent beneficial effects on plant growth is difficult., ENDOPHYTIC FUNGI of the genus Neotyphodium live in symbiosis with many cool-season grasses. The endophyte colonizes the intercellular spaces of all aerial plant parts and depends entirely on the host [...]

The requirements for compressors in refrigeration industry become more demanding each year. Requirements regarding efficiency, durability, and also the possibility / demand of dry running machines are the main driving factors. So far, the majority of compressors are mainly manufactured out of cast iron, aluminum, steel, and other metals (not including sealing elements), which lead to high costs as well as weights. The scope of this work includes a demonstration of new manufacturing methods and material choices for small-scale compressors as well as a possible transfer to even larger machines. A detailed look on the potential of different material classes and compounds will be presented. The paper also takes into consideration if the new materials have to be used for lubricated compressors or if there is even a possibility for an operation without any oil. Thermodynamic and strength limits will be pointed out as well as the potential to substitute the nowadays used metals-based components by lightweight materials. [ABSTRACT FROM AUTHOR]

Summary Somatostatin-14 and its analogue octreotide both exert inhibitory effects on gastrointestinal secretions and may therefore be beneficial in the treatment of gastrointestinal fistulae. There are no studies that have [...]