Capturing drifting species and molecules—Lessons learned from integrated approaches to assess marine metazoan diversity in highly dynamic waters

Marine community diversity surveys require a reliable assessment to estimate ecosystem functions and their dynamics. For these, non-invasive environmental DNA (eDNA) metabarcoding is increasingly applied in zoological studies to complement or even replace traditional morphological identification methods. However, uncertainties remain about the accuracy of the diversity detected with eDNA to capture the actual diversity in the field. Here, we validate the reliability of eDNA metabarcoding in identifying metazoan biodiversity in highly dynamic marine waters of the North Sea. We analyzed biodiversity from water (eDNA) and zooplankton samples with cytochrome c oxidase subunit 1 (COI) and 18S rRNA (18S) metabarcoding at Helgoland Roads and validated the optimal molecular resolution by morphological and molecular zooplankton identification (metabarcoding) with the result of merely a few false-negative detections. eDNA and zooplankton metabarcoding resolved 354 species from all major and in total 16 metazoan phyla. This molecular genetic species inventory overlapped by 95.9% (COI) and 81.9% (18S) with published inventories of local, morphologically identified species, among them neozoa and rediscovered species. Even though half of all species were detected by both eDNA and zooplankton metabarcoding, the methods differed significantly in their detected diversity. eDNA metabarcoding performed very well in cnidarians and annelids, whereas zooplankton metabarcoding identified higher numbers of fish and malacostraca. Species assemblages significantly differed between the individual sampling events and the cumulative number of identified species increased steadily over the sampling period and did not reach saturation. About a third of the species were detected only once while a core community of 22 species was identified continuously. Our study confirms eDNA metabarcoding to be a powerful tool to identify and analyze North Sea fauna in highly dynamic waters and we recommend investing in high sampling efforts by repetitive sampling and replication using at least 0.45 μm filters to increase filtration volume

Neues aus der GDM-Nachwuchsvertretung

Die GDM-Nachwuchsvertretung informiert über veränderte Personalia, Angebote aus dem Jahr 2022 und geplante Angebote für das Jahr 2023

Clinical Presentation, Cholangiographic Features, Natural History, and Outcome: A Series of 16 Cases

Secondary sclerosing cholangitis in critically ill patients (SSC-CIP) is an important differential diagnosis in patients presenting with cholestasis and PSC-like cholangiographic changes in endoscopic retrograde cholangiography (ERC). As a relatively newly described entity, SSC-CIP is still underdiagnosed, and the diagnosis is often delayed. The present study aims to improve the early detection of SSC-CIP and the identification of its complications. A total of 2633 records of patients who underwent or were listed for orthotopic liver transplantation at the University Hospital Charité, Berlin, were analyzed retrospectively. The clinical presentation and outcome (mean follow-up 62.7 months) of the 16 identified SSC-CIP cases were reviewed. Cholestasis was the first sign of SSC-CIP. GGT was the predominant enzyme of cholestasis. Hypercholesterolemia occurred in at least 75% of the patients. SSC-CIP provoked a profound weight loss (mean 18 kg) in 94% of our patients. SSC-CIP was diagnosed by ERC in all patients. The 3 different cholangiographic features detected correspond roughly to the following stages: (I) evidence of biliary casts, (II) progressive destruction of intrahepatic bile ducts, and (III) picture of pruned tree. Biliary cast formation is a hallmark of SSC-CIP and was seen in 87% of our cases. In 75% of the patients, the clinical course was complicated by cholangiosepsis, cholangitic liver abscesses, acalculous cholecystitis, or gallbladder perforation. SSC-CIP was associated with worse prognosis; transplant-free survival was ∼40 months (mean). Because of its high rate of serious complications and unfavorable prognosis, it is imperative to diagnose SSC-CIP early and to differentiate SSC-CIP from other types of sclerosing cholangitis. Specific characteristics enable identification of SSC-CIP. Early cooperation with a transplant center and special attention to biliary complications are required after diagnosis of SSC-CIP

Efficacy and safety of propranolol as first-line treatment for infantile hemangiomas

Beta-blockers are a highly promising treatment modality for complicated infantile hemangiomas (IH). However, data on propranolol as first-line treatment, objective outcome measures and impact on hemodynamics in young infants is limited. We retrospectively evaluated a homogenous group of infants with proliferating complicated IH treated with propranolol (2mg/kg/day). Outcome was assessed by blinded evaluation of clinical photographs by visual analogue scale (VAS), ultrasound examination and ophthalmological review (if appropriate). Tolerance and hemodynamic variables were recorded over time, including a 2-day in-patient observation at the initiation of therapy. Twenty-five infants (median age 3.6 (1.5-9.1) months) were included in the study. The median follow-up-time was 14 (9-20) months and 14 patients completed treatment at a median age of 14.3 (11.4-22.1) months, after a duration of 10.5 (7.5-16) months. In all patients, there was significant fading of colour (with a VAS of −9 (−6 to −9) after 7months) and significant decrease in size of the IH (with a VAS of −8 (−3 to −10) after 7months). Median thickness of the lesions assessed by ultrasound at baseline and after 1month was 14 (7-28) mm and 10 (5-23) mm, respectively (p < 0.01). In children with periocular involvement, astigmatism and amblyopia resolved rapidly within 8weeks. The overall tolerance of propranolol was good, and no relevant hemodynamic changes were noted. Conclusion: Our report supports the excellent effect and good tolerance of this novel therapy, and we propose the use of propranolol as first-line treatment for I

„Illustrieren am Beispiel“ beim Beweisverstehen: Beispielkonstruktionsprozesse von Mathematikstudierenden

Beweisverstehen ist für Studierende neben der Beweiskonstruktion eine der wesentlichen Anforderungssituationen im Bereich des Beweisens, etwa beim Nachvollziehen von Beweisen in Vorlesungen, Übungen oder Lehrbüchern. Jedoch zeigen viele Studierende Schwierigkeiten, Beweise zu verstehen(vgl. z.B. Selden, 2012; Weber, 2001). In der fachdidaktischen Forschung wird deshalb das Thema ‚Beweisverstehen‘ intensiv und facettenreich diskutiert (vgl. Sommerhoff & Brunner, 2021). Insbesondere werden unterschiedliche Unterstützungsstrategien für Verstehensprozesse der Studierenden untersucht, darunter das sogenannte ‚Illustrieren am Beispiel‘ (vgl. Mali, 2014; Mills, 2014), also die Illustration einzelner Beweiszeilen durch Beispiele. Dieser Beitrag stellt erste qualitative Erkenntnisse einer Mixed-Methods-Studie zu Möglichkeiten vor, Beweisverstehen durch Illustrieren am Beispiel in den Zusammenhang der bereits in Bauer et al. (2021) beschriebenen quantitativen Ergebnisse zu setzen und diskutiert mögliche Implikationen für das weitere Vorgehen

Die schweizerischen Kindes- und Erwachsenenschutzbehörden

Ausgangspunkt unseres Beitrages ist die Revision des schweizerischen Kindes- und Erwachsenenschutzrechts. Das 2013 in Kraft getretene Gesetz legte unter anderem die Neuschaffung von Kindes- und Erwachsenenschutzbehörden fest, in deren Entscheidungsgremien unterschiedliche disziplinäre Expertise zur Anwendung kommen soll. Befunde einer eigenen empirischen Studie zu den Auswirkungen politischer Steuerung auf die Organisationen und das professionelle Handeln der Sozialen Arbeit deuten darauf hin, dass die geforderte Interdisziplinarität der Behörde nicht zu einer interprofessionellen Praxis der Fallbearbeitung führte. Anhand der exemplarischen Analyse ausgewählter Interviewsequenzen wird aufzeigen, welche Herausforderungen in einem interdisziplinär zusammengesetzten Handlungsfeld zu bewältigen sind und hierbei insbesondere auch auf die Vorstellungen, Selbstverständnisse und Zuschreibungen der Beteiligten eingegangen