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Wheat Plants Reduce N2O Emissions from Upland Soil Subject to Transient and Permanent Waterlogging
Get PDFClimate change is expected to increase the frequency of extreme soil moisture events, such as winter waterlogging followed by spring drought, particularly in temperate regions of Europe, North America and Northeast China. While N2O emissions from paddy soils under waterlogging and subsequent drainage have been widely studied, knowledge of upland arable soils under wheat cultivation remains limited. We hypothesized that: (1) in upland soils, combined waterlogging and drought reduces N2O emissions compared to continuous waterlogging, and (2) plant presence mitigates soil nitrate accumulation and N2O emissions across different moisture regimes. A greenhouse experiment was conducted using intact upland soil cores with and without wheat under four moisture treatments: control (60% water-holding capacity, WHC), drought (30% WHC), waterlogging, and waterlogging followed by drought. Daily and cumulative N2O fluxes, soil mineral nitrogen (NH4+-002DN and NO3−-N), and total nitrogen uptake by wheat shoots were measured. Prolonged waterlogging resulted in the highest cumulative N2O emissions, whereas the transition from waterlogging to drought triggered a sharp but transient N2O peak, particularly in soils without plants. Wheat presence consistently reduced N2O emissions, likely through nitrate uptake, which limited substrate availability for incomplete denitrification. Moisture regimes strongly affected nitrate dynamics, with drought promoting nitrate accumulation and waterlogging enhancing nitrate loss. These findings highlight the vulnerability of upland soils in regions prone to seasonal moisture extremes. Effective management of soil moisture and nitrogen, including the promotion of plant growth, is essential to mitigate N2O emissions and improve nitrogen use efficiency under future climate scenarios
Low-Cost NIR Spectroscopy Versus NMR Spectroscopy for Liquid Manure Characterization
Get PDFAccurate characterization of liquid manure properties, such as dry matter (DM), total nitrogen (TN), ammonium nitrogen (NH4-N), and total phosphorus (TP), is essential for effective nutrient management in agriculture. This study investigates the use of near-infrared spectroscopy (NIRS) within the 941-1671 nm range, combined with advanced pre-processing and machine learning techniques to accurately predict the liquid manure properties. The predictive accuracy of NIRS was assessed by comparison with nuclear magnetic resonance (NMR) spectroscopy as a benchmark method. A number of 51 liquid manure samples were analyzed in the laboratory for the reference manure properties and scanned with NIRS and NMR. The NIR data underwent spectral pre-processing, which included two- and three-band index transformations and feature selection. Partial least squares regression (PLSR) and LASSO regression were employed to develop calibration models. According to the results, using cohort-tuned models, NIRS showed fair predictive accuracy for DM (R2 = 0.78, RPD = 2.15) compared to factory-calibrated NMR (R2 = 0.68, RPD = 0.81). Factory-calibrated NMR outperformed for chemical properties, with R2 (RPD) of 0.89 (1.74) for TN, 0.97 (5.70) for NH4-N, and 0.95 (2.64) for TP, versus NIRS's 0.66 (1.68), 0.84 (2.45), and 0.84 (2.51), respectively. In this study with 51 samples, two- and three-band indices significantly enhanced NIRS performance compared to raw data, with R2 increases of 34%, 57%, 25%, and 33% for DM, TN, NH4-N, and TP, respectively. Feature selection efficiently reduced NIR spectral dimensionality without compromising the prediction accuracy. This study highlights NIRS's potential as a portable tool for on-site manure characterization, with NMR providing superior laboratory validation, offering complementary approaches for nutrient management
Essays on Nonlinear Contracting under Uncertainty and Asymmetric Information: Trade-off between Risk Sharing and Moral Hazard Problem
Get PDFThe papers in this thesis explore optimal contracting under uncertainty and asymmetric information and the trade-off between the benefits of risk sharing and the drawbacks resulting from moral hazard problem in various agency relationships. The first paper analyzes the consequences of risk sharing and moral hazard problem when an entrepreneur, starting a business, shares not the total business risk, but only the risk associated with a certain area of the firm with an outside financier. The second paper introduces a nonlinear profit-and-loss-sharing arrangement with a fixed payment component that can eliminate (or at least alleviate) the adverse effects of the moral hazard problem in a principal-agent relationship. Paper 2 is presented in two parts. The agent (i.e., the entrepreneur) is assumed to be risk-neutral and risk-averse in the first and second parts, respectively. When the entrepreneur is risk-neutral, nonlinear profit and loss sharing can be arranged so that the incentives of the entrepreneur to extend effort are not diluted. The optimally arranged nonlinear profit and loss sharing is shown to be superior to debt or equity financing when the entrepreneur is risk-averse. The third paper presents such a nonlinear sharing of credit risks in a bank loan credit risk pooling arrangement that the negative effects of the moral hazard problem associated with credit risk transfer instruments are eliminated. It is also shown that the contributions of the participant banks to the loan pool can be arranged in such a way that they all benefit from the diversification of credit risk
Rezensionsteil aus der Zeitschrift Nordelbingen 91.2025
Get PDFSammlung von Rezensionen zu folgenden Titeln: Die Siegel der Klöster in Schleswig-Holstein und Hamburg, hg. v. Oliver Auge, Robert Harlaß und Katja Hillebrand, Schnell + Steiner: Regensburg 2024 (ISBN 978-3-7954-3827-2; Fürstinnen in Schleswig-Holstein. Handlungsspielräume im Spannungsfeld zwischen Dynastie, Familie und Individuum, hg. v. Oliver Auge, Uta Kuhl und Jan Ocker, Universitätsverlag Kiel: Kiel 2024 (ISBN 978-3-928794-92-3); Der frühe Backsteinbau zwischen Ostsee und Alpen, hg. v. Ernst Badstübner, Dirk Schumann und Tilo Schöfbeck, Lukas Verlag: Berlin 2024 (ISBN 978-3-936872-75-0); Karl Peter Röhl. Facetten eines Bauhaus-Künstlers in Kiel, hg. v. Sabine Behrens, Thorleif Schönfeld und Michael Siebenbrodt, Verlag Ludwig: Kiel 2022 (ISBN 978-3-86935-438-5); Rolf Fischer: Zauber und Zwiespalt. Der Kieler Bauhaus-Maler Karl Peter Röhl und die Politik, Verlag Ludwig: Kiel 2024 (ISBN 978-3-86935-476-7); Siedlungsgrün und Stadtgrün. Der Gartenreformer Leberecht Migge (1881–1935), Wachholtz Verlag: Kiel / Hamburg 2022 (ISBN 978-3-529-02225-8); Hugo Distler. Sämtliche Schriften, hg. v. Sven Hiemke, Bärenreiter-Verlag: Kassel 2024 (ISBN 978-3-7618-2489-4); Die Eiserne Brücke von Georg Ludwig Friedrich Laves im Park von Salzau / The Iron Bridge by Georg Ludwig Friedrich Laves in Salzau Park. Geschichte und Restaurierung / Its history and restoration hg. v. Markus Jager, Dölling und Galitz Verlag: Hamburg 2024 (ISBN 978-3-96060-709-0); Kirchenkunst + Zeitgeist. Werke von Otto Flath in Norddeutschland, hg. v. Netzwerk Erinnerungskultur im Bereich der Nordkirche, Netzwerk Erinnerungskultur im Bereich der Nordkirche: Hamburg 2024; Ingo Sommer: Preußische Moderne. Vom Ende der Pracht und einer neuen Baukunst 1918–1933, Duncker & Humblot: Berlin 2024 (ISBN 978-3-428-19157-4); Helmut Stange: Wilhelm Meissner 1770–1842. Ein Schaumburger Baumeister zwischen Revolution und Biedermeier, Wallstein Verlag: Göttingen 2023 (ISBN 978-3-8353-5457-9);Collection of reviews of the following titles: Die Siegel der Klöster in Schleswig-Holstein und Hamburg, ed. by Oliver Auge, Robert Harlaß, and Katja Hillebrand, Schnell + Steiner: Regensburg 2024 (ISBN 978-3-7954-3827-2; Fürstinnen in Schleswig-Holstein. Handlungsspielräume im Spannungsfeld zwischen Dynastie, Familie und Individuum, ed. by Oliver Auge, Uta Kuhl, and Jan Ocker, Universitätsverlag Kiel: Kiel 2024 (ISBN 978-3-928794-92-3); Der frühe Backsteinbau zwischen Ostsee und Alpen, ed. by Ernst Badstübner, Dirk Schumann, and Tilo Schöfbeck, Lukas Verlag: Berlin 2024 (ISBN 978-3-936872-75-0); Karl Peter Röhl. Facetten eines Bauhaus-Künstlers in Kiel, ed. by Sabine Behrens, Thorleif Schönfeld, and Michael Siebenbrodt, Verlag Ludwig: Kiel 2022 (ISBN 978-3-86935-438-5); Rolf Fischer: Zauber und Zwiespalt. Der Kieler Bauhaus-Maler Karl Peter Röhl und die Politik, Verlag Ludwig: Kiel 2024 (ISBN 978-3-86935-476-7); Siedlungsgrün und Stadtgrün. Der Gartenreformer Leberecht Migge (1881–1935), Wachholtz Verlag: Kiel / Hamburg 2022 (ISBN 978-3-529-02225-8); Hugo Distler. Sämtliche Schriften, ed. by Sven Hiemke, Bärenreiter-Verlag: Kassel 2024 (ISBN 978-3-7618-2489-4); Die Eiserne Brücke von Georg Ludwig Friedrich Laves im Park von Salzau / The Iron Bridge by Georg Ludwig Friedrich Laves in Salzau Park. Geschichte und Restaurierung / Its history and restoration hg. v. Markus Jager, Dölling und Galitz Verlag: Hamburg 2024 (ISBN 978-3-96060-709-0); Kirchenkunst + Zeitgeist. Werke von Otto Flath in Norddeutschland, ed. by Netzwerk Erinnerungskultur im Bereich der Nordkirche, Netzwerk Erinnerungskultur im Bereich der Nordkirche: Hamburg 2024; Ingo Sommer: Preußische Moderne. Vom Ende der Pracht und einer neuen Baukunst 1918–1933, Duncker & Humblot: Berlin 2024 (ISBN 978-3-428-19157-4); Helmut Stange: Wilhelm Meissner 1770–1842. Ein Schaumburger Baumeister zwischen Revolution und Biedermeier, Wallstein Verlag: Göttingen 2023 (ISBN 978-3-8353-5457-9)
Jüdische Friedhöfe in Schleswig-Holstein: Gedenken, Bewahrung und Erforschung
Get PDFJüdische Friedhöfe werden für die Ewigkeit angelegt und sind bedeutende Zeugnisse jüdischer Geschichte, Kultur und Religion in Deutschland. In Schleswig-Holstein existieren heute 22 solcher Friedhöfe, deren historische Entwicklung, Erhaltungszustand und gesellschaftliche Bedeutung bislang nur unzureichend erforscht wurden. Der Beitrag nimmt erstmals eine umfassende Bestandsaufnahme vor und beleuchtet zentrale Herausforderungen sowie Perspektiven für den zukünftigen Umgang mit den ›Guten Orten‹. Drei Hauptaspekte stehen dabei im Fokus: (1) Die Rolle der Friedhöfe als Orte des Gedenkens für die jüdische Gemeinschaft und die nichtjüdische Mehrheitsgesellschaft, (2) die Dringlichkeit eines nachhaltigen Erhaltungskonzepts angesichts unzureichender Pflegepauschalen und fortbestehender antisemitischer Bedrohungen sowie (3) die Notwendigkeit einer systematischen wissenschaftlichen Dokumentation, umfassenden Erforschung sowie verstärkten Einbindung in die Bildungs- und Vermittlungsarbeit. Das kürzlich realisierte Informationstafel-Projekt ›Steinerne Zeugen‹ in Schleswig-Holstein zeigt das wachsende öffentliche Interesse an diesem kostbaren kulturellen Erbe. Der Beitrag plädiert für eine integrative Strategie, die Denkmalschutz, Forschung und Erinnerungskultur verbindet, um jüdische Friedhöfe als lebendige Orte jüdischer Geschichte und Gegenwart dauerhaft zu bewahren.Jewish cemeteries are established for eternity and serve as important testimonies to Jewish history, culture and religion in Germany. Today there are 22 such cemeteries in Schleswig-Holstein. Their historical development, state of preservation, and societal significance have so far been insufficiently researched. This article presents the first comprehensive assessment of their current status and highlights key challenges and perspectives for the future management of these ›good places‹. It focuses on three main aspects: (1) the role of the cemeteries as places of remembrance for both the Jewish community and the non-Jewish majority society, (2) the urgent need for a sustainable preservation strategy in view of insufficient maintenance allowances and persistent anti-Semitic threats, and (3) the necessity of systematic scientific documentation, comprehensive research and greater integration into educational and public engagement. The recently realized information board project ›Stone Witnesses‹ in Schleswig-Holstein shows the growing public interest in this valuable cultural heritage. The article argues for an integrative strategy that combines heritage preservation, research and remembrance culture to ensure the enduring protection of Jewish cemeteries as vital sites of Jewish history and contemporary life
Semantic Zoom and Mini-Maps for Software Cities
Get PDFSoftware visualization tools can facilitate program comprehension by providing visual metaphors, or abstractions that reduce the amount of textual data that needs to be processed mentally. One way they do this is by enabling developers to build an internal representation of the visualized software and its architecture. However, as the amount of displayed data in the visualization increases, the visualization itself can become more difficult to comprehend. The ability to display small and large amounts of data in visualizations is called visual scalability. In this paper, we present two approaches to address the challenge of visual scalability in 3D software cities. First, we present an approach to semantic zoom, in which the graphical representation of the software landscape changes based on the virtual camera's distance from visual objects. Second, we augment the visualization with a miniature two-dimensional top-view projection called mini-map. We demonstrate our approach using an open-source implementation in our software visualization tool ExplorViz. ExplorViz is web-based and uses the 3D city metaphor, focusing on live trace visualization. We evaluated our approaches in two separate user studies. The results indicate that semantic zoom and the mini-map are both useful additions. User feedback indicates that semantic zoom and mini-maps are especially useful for large software landscapes and collaborative software exploration. The studies indicate a good usability of our implemented approaches. However, some shortcomings in our implementations have also been discovered, to be addressed in future work
Time-Restricted Feeding Promotes Longevity and Gut Health Without Fitness Trade-Offs
Get PDFTime-restricted feeding (TRF), a dietary intervention involving daily fasting periods, has been associated with metabolic benefits; however, its long-term physiological impact remains unclear. Using Drosophila melanogaster as a model, we investigated the effects of a 16:8 TRF regimen on lifespan, reproductive output, gut health, and microbiota composition. TRF significantly extended lifespan, even when applied only during early adulthood. Notably, this longevity benefit occurred without compromising reproductive fitness, as measured by female fecundity in life's most crucial reproductive phase. TRF promoted gut homeostasis in aged flies by reducing intestinal stem cell proliferation and enhancing epithelial barrier integrity. Furthermore, TRF induced a shift in microbiota composition, increasing the prevalence of gram-negative bacterial taxa. These results show that even short-term TRF interventions at a young age can have long-term physiological benefits. Metabolic reprogramming or increased autophagy are the most likely mechanisms mediating the health-promoting effects of this type of nutritional intervention. TRF is an effective, non-invasive strategy for promoting healthy longevity without significant adverse effects on other aspects of life
Marine snow morphology drives sinking and attenuation in the ocean interior
Get PDFSimultaneous measurements of marine snow (particles larger than 600 µm) morphologies, estimates of their in situ sinking speeds, and midwater attenuation in export plumes were performed for the first time using a biogeochemical (BGC)-Argo float equipped with optical and imaging sensors. The float was deployed and recovered after drifting for 1 year in the sluggish-flow regime of the Angola Basin. Six consecutive chlorophyll a and particulate matter accumulation events were recorded at the surface, each followed by an export plume of sinking aggregates. Objects larger than 600 µm were classified using machine learning recognition and clustered into four morphological categories of marine aggregates. Plankton images were validated by an expert in a few broad categories. Results show that different types of aggregates were produced and exported from the different blooms. The different morphological categories of marine snow had different sinking speeds and attenuation for a similar size, indicating the effect of morphology on sinking speed. However, a typical size-to-sinking relationship for two of the categories and over the larger observed size range (100 µm to a few millimeters) was also observed, indicating the importance of size for sinking. Surprisingly, in situ-calculated sinking speeds were constantly in the lower range of known values usually assessed ex situ, suggesting a methodological effect, which is discussed. Moving away from purely size-based velocity relationships and incorporating these additional morphological aggregate properties will help to improve the mechanistic understanding of particle sinking and provide more accurate flux estimates. When used from autonomous platforms at high frequency, they will also provide increased spatio-temporal resolution for the observation of intermittent export events naturally occurring or induced by human activities
Bivalent Inhibitors of Mannose-Specific Bacterial Adhesion: A Xylose-Based Conformational Switch to Control Glycoligand Distance †
Get PDFFunctional glycomimetics is suited to study the parameters of carbohydrate recognition that forms the basis of glycobiology. It is particularly attractive when a glycoligand allows for the investigation of two different states, such as varying distance between multiple glycoligands. Here, a xylopyranoside was employed as a scaffold for the presentation of two mannoside units which are ligands of the bacterial lectin FimH. The chair conformation of the central xyloside can be switched between a 4C1 and a 1C4 conformation whereby the two conjugated mannoside ligands are flipped from a di-equatorial into a di-axial position. Concomitantly, the distance between the two glycoligands changes and, as a consequence, so does the biological activity of the respective bivalent glycocluster, as shown in adhesion-inhibition assays with live bacteria. Molecular modeling was employed to correlate the inter-ligand distance with the structure of the formed glycocluster-FimH complex. Our study suggests that conformational switches can be employed and further advanced as smart molecular tools to study structural boundary conditions of carbohydrate recognition in a bottom-up approach
Porcine Single-Eye Retinal Pigment Epithelium Cell Culture for Barrier and Polarity Studies
Get PDFAge-related macular degeneration (AMD) is the main cause of blindness in Western nations. AMD models addressing specific pathological pathways are desired. Through this study, a best-practice protocol for polarized porcine single-eye retinal pigment epithelium (RPE) preparation for AMD-relevant models of RPE barrier and polarity is established. Single-eye porcine primary RPE cells (from one eye for one well) were prepared in 12-well plates including Transwell inserts. Different coatings (laminin (Lam), Poly-ᴅ-Lysine (PDL), fibronectin (Fn) and collagens) and varying serum contents (1%, 5% and 10%) were investigated to determine optimal culture parameters for this model. Success rates of cultures, cell number (trypan-blue exclusion assay), morphology/morphometry (light and fluorescence microscopy), protein secretion/expression (ELISA, Western blot), gene expression (qPCR), transepithelial electric resistance (TEER) and polar location of bestrophin 1 (BEST1) by cryosectioning (IHC-Fr) were assessed. Cells seeded on Lam exhibited the highest level of epithelial cells and confluence properties. Fn resulted in the highest cell number growth. Lam and Fn exhibited the highest culture success rates. TEER values and vascular endothelial growth factor secretion were highest when Lam was used. For the first time, polar (Transwell) porcine single-eye RPE morphometry parameters were determined. RPE on Lam showed bigger cells with a higher variety of cell shapes. CIV displayed the lowest claudin 19 expression. The highest basolateral expression of BEST1 was achieved with Lam coating. The higher the serum, the better the cell number increase and confluence success. [...]. Altogether, the most suitable coating of Transwell inserts was Lam, and a reduction in serum to 5% is recommended, as well as a cultivation time of 28 days. A protocol for the use of polar porcine single-eye cultures with validated parameters was established and is provided herein