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The data currently described was generated within the EU/FP7 HeCaToS project (Hepatic and Cardiac Toxicity Systems modeling). The project aimed to develop an in silico prediction system to contribute to drug safety assessment for humans. For this purpose, multi-omics data of repeated dose toxicity were obtained for 10 hepatotoxic and 10 cardiotoxic compounds. Most data were gained from in vitro experiments in which 3D microtissues (either hepatic or cardiac) were exposed to a therapeutic (physiologically relevant concentrations calculated through PBPK-modeling) or a toxic dosing profile (IC20 after 7 days). Exposures lasted for 14 days and samples were obtained at 7 time points (therapeutic doses: 2-8-24-72-168-240-336 h; toxic doses 0-2-8-24-72-168-240 h). Transcriptomics (RNA sequencing & microRNA sequencing), proteomics (LC-MS), epigenomics (MeDIP sequencing) and metabolomics (LC-MS & NMR) data were obtained from these samples. Furthermore, functional endpoints (ATP content, Caspase3/7 and O2 consumption) were measured in exposed microtissues. Additionally, multi-omics data from human biopsies from patients are available. This data is now being released to the scientific community through the BioStudies data repository ( https://www.ebi.ac.uk/biostudies/ ).

Sedimentary ancient DNA (sedaDNA) offers a novel retrospective approach to reconstructing the history of marine ecosystems over geological timescales. Until now, the biological proxies used to reconstruct paleoceanographic and paleoecological conditions were limited to organisms whose remains are preserved in the fossil record. The development of ancient DNA analysis techniques substantially expands the range of studied taxa, providing a holistic overview of past biodiversity. Future development of marine sedaDNA research is expected to dramatically improve our understanding of how the marine biota responded to changing environmental conditions. However, as an emerging approach, marine sedaDNA holds many challenges, and its ability to recover reliable past biodiversity information needs to be carefully assessed. This review aims to highlight current advances in marine sedaDNA research and to discuss potential methodological pitfalls and limitations.

The effects of global warming are especially pronounced in the Arctic: temperatures have increased at a rate twice as fast as in other regions of the world during the past century. This trend implies that the Arctic Ocean will likely become entirely ice-free during the summer before the end of this century. Paleoclimatic studies have shown that abrupt large-volume meltwater discharges into the Arctic Ocean and its surrounding seas, were capable of disturbing the global ocean circulation and triggering further climatic transformations. Hence, a better understanding of the past natural variability of the Arctic Ocean is needed for more accurate model predictions of future climate change. Planktonic foraminifera represent a powerful tool for palaeoceanographic reconstructions. Their fossil assemblages and the chemical composition of their calcite shells allow reconstructing the physical state of the ocean in the past. The correct interpretation of these paleo-reconstructions highly relies on a thorough understanding of species-specific ecology of living planktonic foraminifera in the water column as, for example, preferred depth habitat, calcification conditions, and biotic interactions. In the Arctic Ocean, due to the fragmented observations on this marine group, no consensus exists on the ecological preferences of the different species, hampering the correct interpretation of the paleosignal present in their shells. This thesis aims to extend the understanding of the ecology of Arctic planktonic foraminifera species by focusing on various levels of organismal biology and physiology. To constrain the environmental and biological factors controlling the vertical distribution of the species Neogloboquadrina pachyderma, a compilation of 104 vertical density profiles from the Arctic Ocean and its marginal seas was investigated using a statistical approach (Chapter 2). Contrary to what has been previously assumed, no significant relationship between N. pachyderma depth habitat and depth of chlorophyll maximum was observed. The depth habitat of the species could instead be predicted with a model including sea-ice concentration, surface chlorophyll concentration, and days since ice-break-up as predictors explaining 33% of the observed variability. The biotic interactions of N. pachyderma with the eukaryotic pelagic community were assessed using a single-cell metabarcoding approach (Chapter 3). The eukaryotic DNA present in 39 specimens and contextual seawater from the Baffin Bay was extracted, amplified, and sequenced. The analyses revealed that N. pachyderma is omnivorous as it lives and opportunistically feeds on diatom-fuelled aggregates. The data also showed a particularly high occurrence of reads belonging to Syndiniales in the foraminifera samples, suggesting that this widely distributed parasite could infect N. pachyderma and possibly influence its population dynamics. To test the assumption that planktonic foraminifera can tolerate low salinity and record the chemical signature of past meltwater discharge events in their shells, specimens of Neogloboquadrina incompta were exposed to a gradient of salinities between 35 and 25 PSU (Chapter 4) as part of a culturing study. Survival was monitored over 26 days by measuring the extent of the rhizopodial network. The highest rhizopodial activity occurred at salinity levels between 35 and 31 PSU. The results indicated that the species can survive long-term exposure to salinities as low as 28, but no rhizopodial activity and signs of cytoplasm degradation were observed in all specimens exposed to 25 PSU. The responsiveness of Arctic planktonic foraminifera to current climate change was investigated by analysing a compilation of 51 species-resolved stratified population profiles collected in the Fram Strait between 1985 and 2015 (Chapter 5). The data revealed an ongoing Atlantification of the community not mirrored by changes in local environmental conditions. The abundance of Atlantic expatriates is instead rising because of processes favouring their growth in the Nordic Seas, the “source” area. On the contrary, the resident species Turborotalita quinqueloba showed declining density and habitat shoaling due to the ongoing extensive sea-ice export from the Arctic and associated cooling in the Fram Strait. These conditions favour the other resident species, the polar N. pachyderma being better adapted to the cold conditions of the area. These results advance our understanding of the abiotic and biotic processes regulating the ecology of planktonic foraminifera in the Arctic Ocean and can be used to refine palaeoceanographic reconstructions in the polar regions and to improve predictions of future climate change.

Most research on extant planktonic foraminifera has been directed towards larger species (>0.150 mm) which can be easily manipulated, counted and yield enough calcite for geochemical analyses. This has drawn attention towards the macroperforate clade and created an impression of their numerical and ecological dominance. Drawing such conclusions from the study of such "giants" is a dangerous path. There were times in the evolutionary history of planktonic foraminifera when all species were smaller than 0.1 mm and indeed numerous small taxa, mainly from the microperforate clade, have been formally described from the modern plankton. The significance of these small, obscure and neglected species is poorly characterized and their relationship to the newly discovered hyperabundant but uncharacterized lineages of planktonic foraminifera in metabarcoding datasets is unknown. To determine, who is hiding in the metabarcoding datasets, we carried out an extensive sequencing of 18S rDNA targeted at small and obscure species. The sequences of the newly characterized small and obscure taxa match many of the previously uncharacterized lineages found in metabarcoding data. This indicates that most of the modern diversity in planktonic foraminifera has been taxonomically captured, but the role of the small and neglected taxa has been severely underestimated.

This work was supported by grants from ANR-09-BLAN-0348 POSEIDON, ANR-JCJC06-0142-PALEO-CTD, from Natural Environment Research Council of the United Kingdom (NER/J/S2000/00860 and NE/D009707/1), the Leverhulme Trust and the Carnegie Trust for the Universities of Scotland, from DFG-Research Center/Cluster of Excellence ‘The Ocean in the Earth System’, from the Deutsche Forschungsgemeinschaft KU2259/19 and through the Cluster of Excellence “The Ocean Floor – Earth’s Uncharted Interface”. The planktonic foraminifera genus Globigerinoides provides a prime example of a species-rich genus in which genetic and morphological divergence are uncorrelated. To shed light on the evolutionary processes that lead to the present-day diversity of Globigerinoides, we investigated the genetic, ecological and morphological divergence of its constituent species. We assembled a global collection of single-cell barcode sequences and show that the genus consists of eight distinct genetic types organized in five extant morphospecies. Based on morphological evidence, we reassign the species Globoturborotalita tenella to Globigerinoides and amend Globigerinoides ruber by formally proposing two new subspecies, G. ruber albus n.subsp. and G. ruber ruber in order to express their subspecies level distinction and to replace the informal G. ruber “white” and G. ruber “pink”, respectively. The genetic types within G. ruber and Globigerinoides elongatus show a combination of endemism and coexistence, with little evidence for ecological differentiation. CT-scanning and ontogeny analysis reveal that the diagnostic differences in adult morphologies could be explained by alterations of the ontogenetic trajectories towards final (reproductive) size. This indicates that heterochrony may have caused the observed decoupling between genetic and morphological diversification within the genus. We find little evidence for environmental forcing of either the genetic or the morphological diversification, which allude to biotic interactions such as symbiosis, as the driver of speciation in Globigerinoides. Publisher PDF

The research project develops procedures and digital processes in order to enhance the design and the execution quality of interventions for the conservation of architectural surfaces. The aim is to finally promote the dialogue among disciplines with different natures but which are actually very close. The proposal consists in a mobile software based on the platform FileMaker for the management of restoration operations through the creation of a database organised in modules, permitting to register the analytic documentation of the entire restoration process. Moreover, the software allows to involve directly and at the same time the designer, the works supervisor, the construction company and the offices appointed for the preservation of historical buildings. These figures are called to participate directly and simultaneously in the decision procedure, in order to reduce the lenght of control and realization process in favor of a better cultural and technical quality, thanks to the implementation of “good practices” studied and developed with specific computer systems.

Il capitolo descrive lo svolgimento del cantiere di restauro e consolidamento della Fontana del Nettuno di Bologna, attraverso la ricostruzione cronologica delle scelte operative condotte partendo dalla fase progettuale fino al termine delle lavorazioni sul campo. All'interno del capitolo viene evidenziato come, fin dai primi lavori, siano emerse problematiche inaspettate al momento della progettazione e di come queste siano state risolte durante il cantiere di Restauro. Vengono, infine, riportati alcuni approfondimenti sulle operazioni compiute su elementi specifici del monumento, generalmente tralasciati poiché ritenuti secondari rispetto alle problematiche di conservazione delle superfici: il sistema dei cunicoli, gli elementi di sostegno e ritegno della statua in bronzo, la statica degli elementi lapidei di rivestimento.

MARIA S. MERIAN-Berichte