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Increased Readiness for Water Splitting: NiO-InducedWeakening of Bonds in Water Molecules as Possible Causeof Ultra-Low Oxygen Evolution Potential
No full textThe development of non-precious metal-based electrodes that actively and stably support the oxygen evolution reaction (OER) in water electrolysis systems remains a challenge, especially at low pH levels. The recently published study has conclusively shown that the addition of haematite to H2 SO4 is a highly effective method of significantly reducing oxygen evolution overpotential and extending anode life. The far superior result is achieved by concentrating oxygen evolution centres on the oxide particles rather than on the electrode. However, unsatisfactory Faradaic efficiencies of the OER and hydrogen evolution reaction (HER) parts as well as the required high haematite load impede applicability and upscaling of this process. Here it is shown that the same performance is achieved with three times less metal oxide powder if NiO/H2 SO4 suspensions are used along with stainless steel anodes. The reason for the enormous improvement in OER performance by adding NiO to the electrolyte is the weakening of the intramolecular O─H bond in the water molecules, which is under the direct influence of the nickel oxide suspended in the electrolyte. The manipulation of bonds in water molecules to increase the tendency of the water to split is a ground-breaking development, as shown in this first example
Exploring the role of alpha-1,3-glucan synthases on fungal cell wall integrity in Aspergillus niger (Vortrag)
No full textAlpha-glucan synthases (ags) play a key role in the synthesis of alpha-1,3-glucan, a crucial component of the fungal cell wall that is (i) contributing to its structural integrity and is (ii) involved in cross-linking of different polymers, so that it influences the composition of both: the outer shell and inner membrane of fungal cells.
In the filamentous fungi Aspergillus niger five ags genes are annotated, of which agsA and agsE were shown to be the most highly expressed genes during different stages of development. In addition, an agsE deletion mutant caused smaller micro-colonies as well as a shift in the secretome composition of A. niger, without affecting biomass production. Concurrently, intracellular cross-linking between chitin and beta-glucan is primarily mediated by the seven-membered cell wall-related transglycosylase gene family (crh). Although an impact on cell wall integrity has been expected when deleting the entire crh gene cluster in A. niger, significant alterations in cell wall integrity became only evident when the crh gene cluster deletion was combined with the reduction of alpha-glucan and galactomannan by deleting respective agsE or ugmA.
With this background, we aimed to further explore the impact of ags gene deletions – both individually and as an entire family – on fungal cell wall integrity of A. niger. Using targeted CRISPR/Cas9 technology, we engineered various ags-deficient strains, including the deletion of the entire gene family (ΔagsA-E) in a mutant strain lacking all chitin-glucan cross-linking enzymes (Δcrh, TLF39). Subsequent morphological and biochemical characterization of these mutants pinpoint the importance of agsE for maintaining cell wall stability and suggesting its potential influence on protein production and/or secretion. These findings therefor provide not only new insights into fungal biology but also potential targets for biotechnological applications
Marktanalyse von Gewichtsprogrammen - daraus entstehende Potenziale für das "Ich nehme ab"-Training der DGE
No full textDie vorliegende Bachelorarbeit befasst sich mit einer umfassenden Marktanalyse von Gewichtsreduktionsprogrammen im Zeitraum von März bis Mai 2024. Ziel ist es, die Marktposition und das Potenzial des ICH-nehme-ab-Trainings (INA) der Deutschen Gesellschaft für Ernährung (DGE), das als Selbsthilfemanual und Gruppenkurs eingesetzt wird, im Vergleich zu anderen Programmen zu evaluieren. Zur Analyse wurden die Methoden Desk Research und SWOT-Analyse eingesetzt. Zahlreiche Angebote in Form von Kursen und digitalen Anwendungen stehen für präventive und therapeutische Interventionen zur Verfügung. INA hat gut gestaltete Materialien mit haptischen und visuellen Anreizen und zeichnet sich durch transparente Vorab-Informationen aus. INA ist produktneutral. Nur Ernährungsfachkräfte leiten die Kurse. Folgende Entwicklungsmöglichkeiten wurden identifiziert: digitale Unterstützung ausbauen in Form eines zertifizierten Online-Kurse, eines Forums und/oder einer begleitenden App, um eine breitere Zielgruppe anzusprechen, den Austausch, die langfristige Motivation und die Nachsorge zu verbessern
Digitalisierung des Bestellprozesses in der Gemeinschaftsverpflegung : eine qualitative Analyse am Beispiel der Arbeiterwohlfahrt Weser Ems e.V.
No full textZiel der vorliegenden Arbeit ist, ein digitalisiertes Bestellsystem für die Rehabilitationsklinik der Arbeiterwohlfahrt Weser Ems e.V. zu finden, indem die Ansprüche der MitarbeiterInnen berücksichtigt werden. Dazu werden folgende Forschungsfragen gestellt: Inwieweit kann eine Digitalisierung die Küche des Rehabilitationszentrums optimieren? Warum soll digitalisiert werden? Wie ist das Bestellsystem in der Klinik aufgestellt und wie kann es sich künftig verändern? Welches digitale System entspricht den Anforderungen der Arbeiterwohlfahrt Weser Ems e.V., um eine mögliche Implementierung vorzunehmen? Um die Forschungsfragen zu beantworten, wird zunächst mithilfe einer Beobachtungsmethode der Ist-Zustand im Unternehmen analysiert. Darauf folgt eine induktive qualitative Inhaltsanalyse, um die Sicht der MitarbeiterInnen zu analysieren. Als abschließende Hauptmethode wird eine Nutzwertanalyse durchgeführt, die verschiedene Anbieter der digitalen Bestellsysteme miteinander vergleichen soll
Time and Frequency Domain Analysis of IMU-based Orientation Estimation Algorithms with Comparison to Robotic Arm Orientation as Reference
No full textThis work focuses on time and frequency domain analysis of IMU-based orientation estimation algorithms such as indirect Kalman (IKF), Madgwick (MF), and complementary (CF) filters. Euler angles and quaternions are used for orientation representations. A 6-DoF Bosch MM7.10 IMU is attached to a 6-joint UR5e robotic arm, using the robot’s orientation as the reference. Robotic arm data is obtained using a Real-Time Data Exchange interface and IMU data is obtained via CAN bus. Test signals include pose sequences and generalized binary noise signals. To avoid poor filter performance, the respective filter parameters are tuned. For filters’ evaluation in the time domain, root mean squared (RMSE) and maximum absolute errors are calculated. For the frequency domain analysis, composite frequency response and composite coherence with Hanning windows are calculated. RMSEs are calculated for frequency response magnitude and composite coherence. Based on the composite frequency response phase, the averaged equivalent time delay (AETD) is calculated. For large amplitude, slowly changing signals (stationary and low-dynamics responses as observed in the time domain), MF delivered the best performance. Similarly, for small amplitude, fast-changing signals (dynamic responses as observed in the frequency domain), MF also excelled, though CF's performance was very close to it. IKF consistently performed the worst in both domains, likely due to overfitting during tuning, but it achieved the lowest AETD
Effects of Sulfuric and Citric Acid for Slurry Acidification on Winter Wheat Yield, N- and S-Balance
No full textSlurry can be acidified to reduce ammonia emissions during slurry application. As considerable quantities of sulfuric acid are required, a lot of S is applied to the soil. The aim of this study was to investigate whether the additional S supply from sulfuric acid has a positive effect on plant growth by comparing sulfuric acid with citric acid. Furthermore, the fate of the S supplied in excess to the plant requirement was investigated.
A field experiment was set up with slurry acidified with sulfuric and citric acid. Yield, N and S concentrations of plant and soil samples on three dates during the growing season were measured. At harvest, grain yield was determined, and the harvested crop was analyzed for N and S concentration. After harvest, soil samples were taken on two further dates and soil mineral N (Nmin) and S (Smin) concentrations were measured.
At harvest grain yield and N and S uptake by the grain were the same for the sulfuric and citric acid treatments, but the sulfuric acid treatment had significantly higher Smin levels on all dates. After harvest, Smin was then leached via the 30-60 cm layer into the 60-90 cm layer.
The very high S supply from the sulfuric acid used to acidify the slurry did not affect the yield nor the N and S uptake of the wheat. S that enters the soil in excess of the plant requirements is transferred with the leachate to deeper soil layers
