Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.

Homogeneously developed oak (Quercus robur L.) microcuttings were challenged in a Petri-dish system with the mycobionts Piloderma croceum J. Erikss. & Hjortst. and Paxillus involutus (Batsch) Fr. Non-destructive observations over 10 wk followed by d. wt measurements at the end of the assays served to precisely characterize root and shoot development, dynamics of mycorrhizal colonization and morphological ratio. In the system, plant development, and especially root morphogenesis, had more similarities to those of stump cuttings or of older seedlings than to those of 3-month-old seedlings. Whereas Paxillus involutus displayed early mycorrhizal colonization and had no significant morphological effects on the host Piloderma croceum modified markedly the entire plant development before a delayed mycorrhiza formation. The latter mycobiont stimulated elongation and production of the lateral root system and also increased the leaf surface. However, no corresponding weight increases were noted, which was reflected by significant increase of both specific root length and specific leaf area. These differential effects are discussed in relation to data concerning carbon requirement and auxin production of the mycobionts. The developed system was shown to be highly suitable for comparative studies with diverse mycobionts on recognition and physiological balance between partners before, and in the early stage of, formation of mycorrhizas.

The identity of black alder (Alnus glutinosa (L.) Gaertn.) ectomycorrhizas was investigated using PCR/RFLP analysis of the ITS region from 16 morphotypes sampled at a 60-yr-old black alder stand. A comparison was made with restriction patterns from sporocarps of 28 mycobionts, of which 16 originated from the same stand, the remaining 12 came from two geographically distant alder stands. Eight of the mycorrhizal types could thus be identified, whereas eight mycorrhizal types remained unidentified. The identified mycorrhizas belonged to the genera Russula, Lactarius, Naucoria and Cortinarius. Four of the identified ectomycorrhizal types had identical PCR/RFLP profiles to corresponding fruit bodies from all investigated stands with no detectable intraspecific variation, despite the geographical distance of c. 300 km between the sampling locations. By contrast, intraspecific variation between sporocarps from the different locations was detected in Paxillus rubicundulus, mycorrhizas of which were not found. The diversity of fruiting alder mycobionts at the main experimental plot only partly matched the diversity observed from mycorrhizas when comparing their PCR/RFLP profiles. The results are discussed regarding sampling techniques, PCR/RFLP analyses and ecological aspects.