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Prof. Dr. Rudolf Meyer-Pritzl (1961–2024) und die Christiana Albertina
Get PDFWürdigung des 2024 verstorbenen CAU-Professors Rudolf Meyer-Pritzl, der der Universitätszeitschrift Christiana Albertina über viele Jahre als Mitglied des Redaktionskollegiums und verantwortlicher Redakteur verbunden war.Tribute to CAU Professor Rudolf Meyer-Pritzl, who passed away in 2024 and was closely associated with the university journal Christiana Albertina for many years as a member of the editorial board and as managing editor
Lignocellulosic biomass and its main structural polymers as sustainable materials for (bio)sensing applications
Get PDF(Bio)sensors are integral to various aspects of daily life, contributing to safety, monitoring, and awareness. In modern sensor devices, polymers play an important role, with increasing interest in bio-based materials. Biopolymers, unlike their synthetic counterparts, are abundant in nature and exhibit interesting functional properties that make them highly suitable as biomaterials for sensor technologies. Enhancing sensor performance to achieve a rapid response to stimuli is a key objective in sensor development. Lignocellulosic biomass (LCB) from plants holds promise in meeting such requirements due to its high surface area, tunable surface characteristics (including diverse pore sizes and morphologies), flexibility, printability, low density, and favorable physicochemical and thermal properties. Growing research in recent decades has focused on lignocellulosic composite materials due to their functional and environmentally friendly attributes. This review focuses on the valorization of lignocellulosic biomass and its three main biopolymer constituents (cellulose, hemicellulose, and lignin) for the development of electrochemical (bio)sensors. It also explores the macromolecular structure, sources, and inherent properties of LCB, with emphasis on the three main biopolymers and their applications in sensor technologies. Recent advances in the use of LCB and its structural biopolymers as materials for (bio)sensing applications are described and reviewed. The challenges associated with using these biomaterials in electroanalytical applications are also discussed, along with the exploration of their future potential for developing high-performance sensing technologies
Assessment of Different Methods to Determine NH3 Emissions from Small Field Plots After Fertilization
Get PDFAmmonia (NH3) emissions affect the environment, climate and human health and originate mainly from agricultural sources like synthetic nitrogen fertilizers. Accurate and replicable measurements of NH3 emissions are crucial for research, inventories and evaluation of mitigation measures. There exist specific application limitations of NH3 emission measurement techniques and a high variability in method performance between studies, in particular from small plots. Therefore, the aim of this study was the assessment of measurement methods for ammonia emissions from replicated small plots. Methods were evaluated in 18 trials on six sites in Germany (2021–2022). Urea was applied to winter wheat as an emission source. Two small-plot methods were employed: inverse dispersion modelling (IDM) with atmospheric concentrations obtained from Alpha samplers and the dynamic chamber Dräger tube method (DTM). Cumulative NH3 losses assessed by each method were compared to the results of the integrated horizontal flux (IHF) method using Alpha samplers (Alpha IHF) as a micrometeorological reference method applied in parallel large-plot trials. For validation, Alpha IHF was also compared to IHF/ZINST with Leuning passive samplers. Cumulative NH3 emissions assessed using Alpha IHF and DTM showed good agreement, with a relative root mean square error (rRMSE) of 11%. Cumulative emissions assessed by Leuning IHF/ZINST deviated from Alpha IHF, with an rRMSE of 21%. For low-wind-speed and high-temperature conditions, NH3 losses detected with Alpha IDM had to be corrected to give acceptable agreement (rRMSE 20%, MBE +2 kg N ha−1). The study shows that quantification of NH3 emissions from small plots is feasible. Since DTM is constrained to specific conditions, we recommend Alpha IDM, but the approach needs further development
Diving into the deep: fungal diversity in the newly discovered hydrothermal vents of Hatiba Mons, Red Sea
Get PDFIntroduction: Hydrothermal vents are among Earth’s most extreme ecosystems, characterized by high temperatures, elevated metal concentrations, and steep chemical gradients that sustain specialized microbial life. Although bacterial and archaeal communities in these environments have been extensively studied, fungal diversity remains poorly understood. The recently discovered Hatiba Mons hydrothermal vent field in the Red Sea Rift provides a unique setting to investigate fungal communities in a hypersaline, metal-rich environment. Methods: We analyzed fungal diversity in crusts, sediments, and microbial mats collected from five active vent sites at Hatiba Mons. A total of 38 subsamples were obtained using a remotely operated vehicle (ROV) during the KRSE Aegaeo RV cruise in May 2022. DNA was extracted, and the fungal ITS rRNA gene region was sequenced on an Illumina MiSeq platform. Sequence processing and taxonomic assignment were performed with QIIME2 and the UNITE database, while downstream statistical analyses were conducted in R with phyloseq. Results: Fungal community composition varied significantly across sample types, as shown by Principal Coordinates Analysis (PCoA) and confirmed by PERMANOVA. Ascomycota, Basidiomycota, and Chytridiomycota dominated the assemblages. Functional predictions using FUNGuild revealed diverse ecological roles, including saprotrophic, symbiotic, and pathogenic lifestyles. This study provides the first characterization of fungal communities in the Hatiba Mons hydrothermal system. The distinct taxonomic and functional profiles observed suggest that fungi contribute to biogeochemical cycling and ecosystem dynamics in extreme marine habitats. These findings expand current knowledge of fungal ecology in hydrothermal vents and underscore the importance of including fungi in future deep-sea microbiological research
A sensitive bioassay to measure NOD1/2 ligands in human serum reveals differential postprandial NOD2 activation
Get PDFFood intake is associated with the occurrence of components and metabolites from the gut microbiota in the bloodstream. Using a widely utilised cell-based assay to measure bacterial peptidoglycan via pattern-recognition receptor activation, we found that the performance of this assay is significantly influenced by the presence of other serum components. To address this challenge, an alternative luciferase-based reporter assay protocol was established to accurately measure NOD1 and NOD2 activation by serum samples with high sensitivity. Utilising postprandial human serum samples, we tested this assay and showed that the concentration of NOD2-activating ligands differed in the postprandial phase. Together, we provide a protocol to measure NOD1/2 activation by human serum samples and highlight a role for NOD2 in the postprandial response
Lactate in Drainage Fluid to Predict Complications in Robotic Esophagectomies-A Pilot Study in a Matched Cohort
Get PDFBackground/Objectives: Despite advances in minimally invasive procedures, anastomotic leakages (ALs) after esophageal resections mark the most feared complication. Its early detection can lead to quick interventional treatment with improved survival. Nonetheless, early detection remains challenging, and scores are imprecise and complex. Methods: In our study we analyzed mediastinal drainage fluid to find parameters suggesting AL even before it became clinically evident and correlated them to routine biomarkers. All patients with AL after robotically assisted esophageal resections were included and matched 1:1 with uneventful controls. Additionally, transhiatal distal esophageal resections operated during this period were included. Drainage fluid was collected on postoperative days (PODs) 1-4 with consecutive blood gas analysis. Test quality was determined by the area under the curve (AUC) of the receiver operating characteristic curve (ROC). Results: In total, 40 patients were included, with 17 developing AL. There were no significant differences in gender, age, BMI or oncological treatment. The 30-day morbidity rate was 65.0%. The study was restricted to events in the first 12 days. While lactate value in drainage fluid differed significantly from POD 3 onwards in the two groups, serum CRP remained without significant differences. We developed the LacCRP score (CRP/30 + lactate/2). The AUC on POD 3 was 0.96, with a sensitivity and specificity of 100% and 75%, respectively. An estimator of 1.08 was found in multivariate analysis: one-point increase in the LacCRP score increases AL probability by 8%. Conclusions: This study demonstrates that postoperative lactate determinations in drainage fluid can predict AL after esophageal resection, and its combination with serum CRP results in a reliable LacCRP score
The sustainable expansion of seaweed as a restorative aquaculture: using a carrying capacity framework that integrates barriers to expansion and ecosystem services
Get PDFSeaweed-based lower trophic aquaculture (LTA) offers a promising pathway to meet rising resource demands while restoring degraded coastal ecosystems. Seaweeds provide valuable ecosystem services (ES), including water-quality improvement, nutrient removal, and habitat provision, while supplying biomass for food, feed, cosmetics, and pharmaceuticals. Europe’s seaweed sector is still emerging, making precaution and clear sustainability thresholds essential. This thesis investigates how seaweed aquaculture can expand responsibly by combining desk research with field studies at Ocean Rainforest (Faroe Islands), Ocean Forest (Norway), and Algolesko (France). Three ES, carbon sequestration, nutrient bioextraction, and biodiversity support, were evaluated. While sequestration during growth remains uncertain and relatively small, larger climate benefits may come from product substitution. Nutrient removal proved measurable but highly site-specific. Biodiversity findings showed that multi-year systems, such as ORF’s, significantly enhance biodiversity and resemble natural seaweed communities. Negative impacts remain poorly understood, underscoring the need for systematic monitoring. To guide sustainable scale-up, the thesis develops a carrying capacity (CC), based framework that defines acceptable environmental thresholds and integrates ES into decision-making. Although CC is recognized in the Ecosystem Approach to Aquaculture, it is not yet embedded in policy, and European expansion faces barriers including governance fragmentation and market immaturity. Quantifying and valuing ES could help overcome these barriers by improving financial viability, spatial planning, and social acceptance. The thesis highlights that incorporating CC, ES, and social dimensions is essential for enabling restorative and sustainable seaweed aquaculture in Europe
Mikrobielle Regulation von Hexokinase 2 und deren Einfluss auf Entzündung
Get PDFDas intestinale Mikrobiom spielt eine entscheidende Rolle bei der Regulation von Hexokinase 2. Diese regulatorische Interaktion erfolgt durch die Metabolite des Mikrobioms, insbesondere die kurzkettigen Fettsäuren. Acetat induziert die Expression von HK2 und trägt damit zu einem schwerwiegenderen Verlauf im murinen Colitis-Modell bei. Auf der anderen Seite bewirkt Butyrat eine Depletion von HK2 sowohl in vitro als auch in vivo. Diese Depletion führt zu einem deutlich milderen Krankheitsverlauf im murinen Colitis-Modell und reduziert die Anfälligkeit für Zelltod, sowohl in vivo als auch ex vivo. Die Auswirkungen der HK2-Depletion spiegeln sich in vergleichbaren Einschränkungen der mitochondrialen Funktion wider, wie sie auch durch den gänzlichen Verlust von HK2 entstehen. Der Signalweg zwischen HK2 und Butyrat wird maßgeblich durch die HDAC8 vermittelt. Die beschriebenen Effekte der kurzkettigen Fettsäuren auf den Krankheitsverlauf zeigen eine Spezifität für HK2 in intestinalen Epithelzellen, da sie keinen Einfluss auf die Krankheitsaktivität von Mäusen, denen HK2 im intestinalen Epithel fehlt, haben. Die Vorarbeiten im Rahmen dieser Publikation legten nahe, dass der Verlust von HK2 in intestinalen Epithelzellen zu einem protektiven, durch Mitochondrien vermittelten anti-inflammatorischen Phänotyp führt, was sich in einer verringerten Anfälligkeit für Zelltod manifestiert. In chronisch-entzündlichen Erkrankungen, darunter auch chronisch-entzündliche Darmerkrankungen, ist die HK2-Expression in intestinalen Epithelzellen signifikant erhöht. Diese Erkenntnisse in Betracht ziehend, lässt sich die Interaktion zwischen HK2 und dem mikrobiellen Metabolit Butyrat als vielversprechender, neuartiger Therapieansatz für chronisch-entzündliche Darmerkrankungen beschreiben
Südschleswigdänisch: Eine strukturelle Bestandsaufnahme aus dialektologischer Perspektive
Get PDFDieses Buch schließt eine seit Jahrzehnten bestehende Forschungslücke zum Südschleswigdänischen, der von den Angehörigen der dänischen Minderheit gesprochenen dänischen Varietät. Basierend auf den Daten von 157 Gewährspersonen aller Altersgruppen aus ganz Südschleswig werden erstmals charakteristische morphosyntaktische Strukturen des Südschleswigdänischen umfassend auf empirischer Grundlage beschrieben und analysiert. Im Mittelpunkt stehen dabei der Einfluss der sprachsozialen Faktoren ›Alter‹, ›dänischsprachiger Input‹, ›Geschlecht‹ und ›Wohnort‹ auf den Sprachgebrauch, die Anwendung dialektologischer Standardverfahren bei der Erhebung von Daten zum stigmatisierten Sprachgebrauch sowie die Modellierung mehrsprachigen Sprachwissens im Rahmen der Diasystematischen Konstruktionsgrammatik. Die Ergebnisse zeigen, dass das Südschleswigdänische keine defizitäre Varietät ist, sondern sich seine Grammatik kognitiv plausibel aus dem sprachlichen Input der mehrsprachigen Sprachgemeinschaft und ihrer Präferenz für sprachübergreifende Konstruktionen erklärt. Während Geschlecht und Wohnort keinen Einfluss haben, wirken sich hingegen Alter und alltäglicher dänischsprachiger Input signifikant auf die Ergebnisse aus.This book closes a research gap that has existed for decades regarding South Schleswig Danish, the Danish variety spoken by members of the Danish minority in South Schleswig. Based on data from 157 speakers of all age groups across the entire region of South Schleswig, it provides the first comprehensive, empirically grounded description and analysis of the characteristic morphosyntactic structures of South Schleswig Danish. The study examines the influence of the sociolinguistic factors ›age‹, ›Danish-language input‹, ›gender‹, and ›place of residence‹ on language use, the application of dialectological standard methods for collecting data on stigmatized language use, and the modeling of multilingual linguistic knowledge within the framework of Diasystematic Construction Grammar. The results show that South Schleswig Danish is by no means a deficient variety; rather, its grammar can be explained in cognitively plausible terms through the linguistic input of a multilingual speech community and its preference for common constructions. While gender and place of residence show no effects, age and everyday Danish-language input have significant impacts on the results.Denne bog lukker et årtier langt forskningshul om sydslesvigskdansk, den danske varietet, som tales af medlemmerne af det danske mindretal i Sydslesvig. På baggrund af data fra 157 informanter i alle aldersgrupper og fra hele Sydslesvig gives der for første gang en omfattende, empirisk funderet beskrivelse og analyse af de karakteristiske morfosyntaktiske strukturer i sydslesvigskdansk. Undersøgelsen fokuserer på betydningen af de sprogsociale faktorer ›alder‹, ›danskinput‹, ›køn‹ og ›bopæl‹ for sprogbrugen, på anvendelsen af dialektologiske standardmetoder til indsamling af data om stigmatiseret sprogbrug samt på modelleringen af flersproget sprogviden inden for rammerne af Diasystematisk Konstruktionsgrammatik. Resultaterne viser, at sydslesvigskdansk på ingen måde er en deficitær varietet; dets grammatik kan derimod forklares kognitivt plausibelt gennem det sproglige input i et flersproget sprogfællesskab og talerens præference for fælles konstruktioner. Mens køn og bopæl ikke har nogen indflydelse, har alder og dagligt danskinput derimod en signifikant effekt på resultaterne
Efficient and versatile rapeseed transformation for new breeding technologies
Get PDFMany gene functions are widely studied and understood in Arabidopsis; however, the lack of efficient transformation systems often limits the application and verification of this knowledge in crop plants. Brassica napus L., a member of the Brassicaceae family, is usually transformed by Agrobacterium-mediated hypocotyl transformation, but not all growth types are equally amenable to transformation. In particular, winter rapeseed, which requires vernalization to initiate flowering, is recalcitrant to in vitro regeneration and transformation. The analysis of gene functions in rapeseed is further complicated by the allotetraploid nature of its genome and the genome triplication within the Brassica genus, which has led to the presence of a large number of gene homologs for each Arabidopsis ortholog. We have established a transformation method that facilitates the regeneration of winter rapeseed by using the WUSCHEL gene from Beta vulgaris. This allowed us to efficiently transform a winter and spring rapeseed genotype in small-scale experiments. As proof of principle, we targeted BnCLV3 and BnSPL9/15 with CRISPR/Cas9 and showed that entire gene families are effectively edited using this transformation protocol. This allowed us to simultaneously study many redundantly acting homologous genes in rapeseed. We observed mutant phenotypes for BnCLV3 and BnSPL9/15 in primary transformants, indicating that biallelic knockouts were obtained for up to eight genes. This allowed an initial phenotypic characterization to be performed already a few months after starting the experiment