Contribution to the knowledge of the aquatic macroinvertebrate fauna of Bükkösdi-víz (Mecsek Mountain, SW Hungary)

In 2018 and 2019, quantitative aquatic macroinvertebrate samplings were carried out in the river network of the Bükkösdi-víz (Mecsek Mountain). The identification of 325,865 macroinvertebrate specimens originated from 40 sampling sites resulted in the occurrences of 125 different species belonging to 12 higher taxa (Gastropoda – 9, Bivalvia – 1, Hirudinea – 4, Malacostraca – 6, Ephemeroptera – 16, Odonata – 12, Plecoptera – 3, Heteroptera – 19, Coleoptera – 23, Megaloptera – 3, Neuroptera – 1, Trichoptera – 28), including 8 protected (Bivalvia: Unio crassus, Odonata: Calopteryx virgo, Coenagrion ornatum, Gomphus vulgatissimus, Onychogomphus forcipatus, Orthetrum brunneum, Heteroptera: Aquarius najas, Neuroptera: Osmylus fulvicephalus) and 1 strictly protected species (Odonata: Cordulegaster heros)

Flow Intermittence Drives the Benthic Algal Composition, Biodiversity and Diatom-Based Quality of Small Hilly Streams in the Pannonian Ecoregion, Hungary

Climate change is putting increasing pressure on flowing waters. Drastic water level fluctuations in rivers or drying up of small and medium-sized streams all contribute to the biodiversity crisis threatening freshwater ecosystems. Benthic diatoms are important elements of biofilm in small streams. However, knowledge on the relationship between benthic diatoms and flow intermittence is incomplete, especially in regions recently impacted by recurrent drying. Thus, we investigated benthic diatom flora of small intermittent, hilly streams in the warm temperate region of Europe (the Pannonian Ecoregion). Our hypotheses were addressed to compositional changes, biodiversity loss and diatom-based ecological assessment. The results revealed clear flow intermittence-induced differences in taxa and trait composition of diatoms. Altogether six species for the dry phase and three species in the aquatic phase were identified as indicative ones by using indicator value analyses. In contrast to water regime induced changes in assemblages, there was a seasonal overlap in taxa and trait composition. During the study period, the drying up of streams did not result in significant biodiversity loss either at taxa or trait levels. Functional dispersion, however, reduced significantly by summer. Overall, neither the hydrological regime nor seasonal changes had a significant effect on diatom-based quality indices, except for the Rott trophic index (TID index). The TID index values were significantly lower in dry phases than in aquatic ones. These results suggested that the drying up of streams has a very complex influence on benthic diatoms. It seems that taxonomical and functional redundancy can reduce the negative impact of short-time flow intermittence on assemblages. As a practical benefit, the results are the first to support the use of diatom-based quality indices in the assessment of flow intermittence in the temperate region

ATLAS liquid argon calorimeter back end electronics

The Liquid Argon calorimeters play a central role in the ATLAS (A Toroidal LHC Apparatus) experiment. The environment at the Large Hadron Collider (LHC) imposes strong constraints on the detectors readout systems. In order to achieve very high precision measurements, the detector signals are processed at various stages before reaching the Data Acquisition system (DAQ). Signals from the calorimeter cells are received by on-detector Front End Boards (FEB), which sample the incoming pulse every 25ns and digitize it at a trigger rate of up to 75~kHz. Off-detector Read Out Driver (ROD) boards further process the data and send reconstructed quantities to the DAQ while also monitoring the data quality. In this paper, the ATLAS Liquid Argon electronics chain is described first, followed by a detailed description of the off-detector readout system. Finally, the tests performed on the system are summarized

New results on diamond pixel sensors using ATLAS frontend electronics

Diamond is a promising sensor material for future collider experiments due to its radiation hardness. Diamond pixel sensors have been bump bonded to an ATLAS pixel readout chip using PbSn solder bumps. Single chip devices have been characterised by lab measurements and in a high-energy pion beam at CERN. Results on charge collection, spatial resolution, efficiency and the charge carrier lifetime are presented

New results on diamond pixel sensors using ATLAS frontend electronics

Diamond is a promising sensor material for future collider experiments due to its radiation hardness. Diamond pixel sensors have been bump bonded to an ATLAS pixel readout chip using PbSn solder bumps. Single chip devices have been characterised by lab measurements and in a high-energy pion beam at CERN. Results on charge collection, spatial resolution, efficiency and the charge carrier lifetime are presented