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Effect of protected zone on polychaete diversity, abundance and distribution in the Wadden Sea intertidal zone
No full textPolychaetes are a diverse group of marine invertebrates widely distributed in soft sediments. This study examined potential differences in the abundance and species composition of polychaetes in public and protected areas of the Wadden Sea National Park in northern Germany. The two sampled areas differed in the level of ecological disturbance; the public beach being used for human recreation while the protected area was a breeding place for birds and accessible only to researchers. Polychaetes were sampled in the intertidal zone on each side of the fence separating the public and protected areas. Samples were analyzed for species abundance using an independent sample t-test and species diversity examined using the Shannon-Weiner Diversity Index. 30 total sites (15 protected and 15 public) were sampled over a period of 3 days at the end of July 2024, polychaetes were collected and identified to species level resulting in 251 total observations of 11 distinct species. Statistical analysis demonstrated no difference in polychaete abundance or species composition between the protected and public areas. This supports the conclusion that polychaete populations in the Wadden Sea National Park are not heavily impacted by predation from migrating birds living in the protected area and are resilient to disturbance caused by human activities on the public beach.Peer Reviewe
Imputation of missing land carbon sequestration data in the AR6 Scenarios Database
No full textThe AR6 Scenarios Database is a vital repository of climate change mitigation pathways used in the latest Intergovernmental Panel on Climate Change (IPCC) assessment cycle. In its current version, many scenarios in the database lack information about the level of anthropogenic carbon dioxide (CO2) removal via land sinks, as net-negative CO2 emissions and gross removals on land are not always separated and are not consistently reported across models. This makes scenario analyses focusing on CO2 removal challenging. We test and compare the performance of different regression models to impute missing data on land carbon sequestration for the global level and for several sub-global macro-regions from available data on net CO2 emissions from agriculture, forestry, and other land uses. We find that a k-nearest neighbors regression performs best among the tested regression models and use it to impute and provide two publicly available imputation datasets (10.5281/zenodo.13373539, Prütz et al., 2024) on CO2 removal via land sinks for incomplete global scenarios (n=404) and incomplete regional R10 scenario variants (n=2358) of the AR6 Scenarios Database. We discuss the limitations of our approach, the use of our datasets for secondary assessments of AR6 scenario ensembles, and how this approach compares to other recent AR6 data reanalyses.Peer Reviewe
Infrastructures and feelings of ontological (in)security in times of crisis: Lessons from rural areas in British Columbia
No full textIn government guidelines the strengthening of rural infrastructure is often seen as a central building block to create economically prosperous, well‐developed rural regions and to support the well‐being of local communities. We challenge this assumption by analyzing the subjective handling of infrastructures in a remote rural area in British Columbia, Canada. Based on the analysis of empirical material from photography‐supported interviews, we argue that fully capturing the influence of infrastructures on local communities requires a relational approach to infrastructures understood as infrastructuring. Derived from the conceptualization of infrastructuring in science and technology studies, we developed the notion of infrastructural autonomy. With the notion of infrastructural autonomy, we are able to outline our findings that subjective and place‐sensitive handlings of infrastructures promote gains in personal ontological security. Based on our qualitative study, we argue that a closer examination of the subjective relation between a place, its infrastructure, and its inhabitants is crucial to understand the infrastructural needs of a place as well as the well‐being of its users.Dans les directives et politiques gouvernementales, la consolidation des infrastructures rurales est souvent vue comme un élément essentiel pour façonner des régions rurales prospères et soutenir le bien‐être des communautés locales. Nous remettons en cause ce postulat en analysant le traitement subjectif des infrastructures dans une zone rurale isolée de la Colombie‐Britannique, au Canada. En nous appuyant sur l'analyse de matériel empirique issu d'entretiens photographiques, nous soutenons qu'il est nécessaire d'adopter une approche relationnelle des infrastructures afin de saisir pleinement l'influence des infrastructures sur les communautés locales. Plus précisément, nous avons développé une notion d'autonomie infrastructurelle dérivée de la conceptualisation des infrastructures dans les études scientifiques et technologiques. Grâce à cette notion d'autonomie infrastructurelle, nous pouvons affirmer que les manipulations subjectives et sensibles aux lieux associées aux infrastructures entraînent des gains en matière de sécurité ontologique personnelle. De plus, en nous basant sur notre étude qualitative, nous soutenons qu'une analyse plus approfondie de la relation subjective entre un lieu, ses infrastructures et ses habitants est cruciale afin de comprendre les besoins en infrastructures d'un lieu ainsi que le bien‐être des usagers.Key messages: Counter to the modernist equation in which infrastructural development leads to greater well‐being, we argue that individual and place‐sensitive handlings of infrastructure may increase ontological security. Fully grasping the relation between a place, its infrastructures, and its inhabitants requires adopting a subjective approach to infrastructure—“infrastructuring”—to reveal concealed insights into infrastructural needs. Based on a qualitative case study from rural British Columbia, the concept of “infrastructural autonomy” supports an understanding of the relational and place‐sensitive character of infrastructures.Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659Peer Reviewe
Equivalence between Gromov-Witten invariants: domain dependent pertubation and Kuranishi structure approaches
No full textIn dieser Dissertation etablieren wir, dass für Kurven vom Geschlecht null die Homologieklasse, die durch den von Cieliebak und Mohnke mittels domänenabhängiger Störung konstruierten rationalen Pseudozyklus induziert wird, äquivalent ist zu der Homologieklasse, die durch die von Fukaya mittels Kuranishi-Struktur definierte virtuelle Fundamentalklasse induziert wird.In this thesis, we establish that for genus zero curves, the homology class induced by the rational pseudocycle—constructed by Cieliebak and Mohnke through domain dependent perturbation—is equivalent to the homology class induced by the virtual fundamental class defined by Fukaya using Kuranishi structure
A truncated variant of the ribosome-associated trigger factor specifically contributes to plant chloroplast ribosome biogenesis
No full textMolecular chaperones are essential throughout a protein’s life and act already during protein synthesis. Bacteria and chloroplasts of plant cells share the ribosome-associated chaperone trigger factor (Tig1 in plastids), facilitating maturation of emerging nascent polypeptides. While typical trigger factor chaperones employ three domains for their task, the here described truncated form, Tig2, contains just the ribosome binding domain. Tig2 is widely present in green plants and appears to have acquired an entirely different task than co-translational nascent polypeptide folding. Tig2 deletion results in remarkable leaf developmental defects of cold-exposed Arabidopsis thaliana plants and specific defects in plastidic ribosomes. Our data indicate that Tig2 functions during ribosome biogenesis by promoting the maturation of the large subunit. We hypothesize that Tig2 binding to the ribosomal tunnel-exit surface aids protecting this sensitive surface during assembly. Tig2 illustrates a fascinating concept of how a chaperone domain evolved individually, serving a completely different molecular task.Deutsche Forschungsgemeinschaft (German Research Foundation)https://doi.org/10.13039/501100001659Ministeriums für Wissenschaft, Weiterbildung und Kultur (Ministerium für Wissenschaft, Weiterbildung und Kultur Rheinland-Pfalz)https://doi.org/10.13039/501100010960Carl-Zeiss-Stiftung (Carl Zeiss Foundation)https://doi.org/10.13039/100007569Peer Reviewe
Toward Understanding the Built-in Field in Perovskite Solar Cells through Layer-by-Layer Surface Photovoltage Measurements
No full textThe built-in voltage (VBI) is a key parameter for solar cell operation, yet in perovskite solar cells the distribution, magnitude, and origin of the VBI remains poorly understood. In this work, we systematically studied the VBI in pin-type perovskite solar cells based on different hole transport layers (TLs). To this end, we determine the surface photovoltage (SPV) of partial and complete device stacks layer-by-layer by measuring the work function (WF) under dark and light (equivalent AM1.5G) conditions with Kelvin probe (KP) and photoemission spectroscopy (UPS) measurements in 3 different laboratories. We demonstrate that the SPV increases upon the addition of each additional layer until it equals the open-circuit voltage (VOC) of the full device. This suggests that both the electron and hole transport layer (HTL/ETL) enlarge the SPV, by improving the separation of photogenerated carriers. Yet, the contribution of both transport layers to the total SPV of the device is small (in the range of ≈100 to 200 meV) and the largest contribution to the SPV originates from the top metal electrode (≈500 meV). The results suggest that the VBI of pin-type perovskite solar cells is largely a result of the work-function difference of the electrodes. With regard to films (or incomplete cell stacks), our simulations can reproduce the measured SPV, and measured quasi-Fermi level splitting (>VOC) in partial cell stacks without a significant internal field consistent with the experimental data. This work establishes layer-by-layer SPV measurements, which are easily accessible, as a key tool for understanding device performance and internal energetics, similar to layer-by-layer QFLS measurements.Helmholtz-Zentrum Berlin f?r Materialien und Energie 10.13039/100013110Deutsche Forschungsgemeinschaft 10.13039/501100001659Deutsche Forschungsgemeinschaft 10.13039/501100001659Volkswagen Foundation 10.13039/501100001663Universit?t Potsdam 10.13039/501100004238Chinese University of Hong Kong 10.13039/501100004853Bundesministerium f?r Wirtschaft und Energie 10.13039/501100006360Peer Reviewe
Seeing Your Religion: Diskriminierung und Rassismus gegenüber Muslim*innen auf dem deutschen Arbeitsmarkt
No full textKey Points: (1) Mit 5.100 Betrieben durchgeführte Umfrage-Experimente liefern Belege für antimuslimische Diskriminierung in den Einstellungsentscheidungen von Arbeitgeber*innen in Deutschland. (2) Die Befunde legen nahe, dass dem Arbeits- und Fachkräftemangel in Deutschland auch durch den Abbau von Diskriminierung in den Einstellungsentscheidungen von Arbeitgeber*innen begegnet werden könnte. (3) Wir empfehlen Aufklärungskampagnen zum Ausmaß der Arbeitsmarktdiskriminierung gegenüber Muslim*innen, sowie zu den ökonomischen Nachteilen, die Betrieben dadurch entstehen. (4) Empfehlenswert sind zudem flächendeckende und institutionalisierte Antidiskriminierungstrainings, insbesondere für kleinere Betriebe etwa im Rahmen von IHK Meisterkursen.Peer Reviewe
Flash Communication: Ligand Centered Cooperative O–H Bond Splitting by a Mo(CO)5(phosphine) Complex
No full textThe synthesis and reactivity of a molybdenum carbonyl complex ligated by geometrically constrained phosphorus trisamide are reported. Reaction with potassium tert -butoxide or methanol triggers ligand-centered substrate activation, leading to planarization of the phosphine donor ligand. P–O bond formation, decarbonylation, and insertion of the molybdenum center into a ligand P–N bond result in the formation of molybdenum tetracarbonyl complexes ligated by rigid N,P-chelate ligands.Fonds der Chemischen Industrie 10.13039/100018992Peer Reviewe
On lauter so’ne quirks – some amendments to Eckardt 2006: ch. 7
No full textThis paper is concerned with the predeterminer lauter in German (cf. Eckardt 2002, 2006) and aims at showing two things: First, the distribution of lauter can be more closely determined if combined with so’n (Hole and Klumpp 2000; Lenerz and Lohnstein 2005; von Heusinger 2012). This possibility suggests that lauter is not a determiner. Secondly, I propose that lauter’s resistance to split topicalization in German is to be found in its syntax: I show that if we adopt the symmetric-Merge approach to the phenomenon by Ott (2012, 2015), not only do the commonly observed facts fall in line, but new ones involving lauter do as well, which prove problematic for a stranding account. Crucially, lauter lacks a pronominal/N-elliptical use implicated in the former analysis
Multi-environment field trials for wheat yield, stability and breeding progress in Germany
No full textThe article processing charge was funded by the Open Access Publication Fund of Humboldt-Universität zu Berlin.Multi-environmental trials (MET) with temporal and spatial variance are crucial for understanding genotype-environment-management (GxExM) interactions in crops. Here, we present a MET dataset for winter wheat in Germany. The dataset encompasses MET spanning six years (2015–2020), six locations and nine crop management scenarios (consisting of combinations for three treatments, unbalanced in each location and year) comparing 228 cultivars released between 1963 and 2016, amounting to a total of 526,751 data points covering 24 traits. Beside grain yield, ten agronomic traits, four baking quality traits, plant height, heading date, maturity date and six fungal disease infection indices are included. Additionally, we provide management records, including fertilizer use, plant protection measures, irrigation, and weather data. We demonstrate how this dataset can address four agronomic questions related to GxExM interactions. Further potential applications of the dataset include empirical analyses, genomic and enviromic analyses for breeding targets, or development of decision-supporting models for agricultural management and policy decisions.Deutsche Forschungsgemeinschaft (German Research Foundation)https://doi.org/10.13039/501100001659Bundesministerium für Bildung und Forschung (Federal Ministry of Education and Research)https://doi.org/10.13039/501100002347Peer Reviewe