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Between Trust and Ambivalence: How Does Trainee Teachers’ Perception of the Relationship With Their Mentors Explain How Trainee Teachers Experience Their Work?
(2023-11-23)
The study aims to identify profiles of trainee teachers in terms of their stress and work experiences and to uncover profile differences in regard to dropout intentions and perceived relationships between trainee teachers and their mentors. Based on data from 1,756 German trainee teachers, three distinct stress and work experience profiles could be identified. Trainee teachers with high levels of stress and negative work experiences exhibit higher dropout intentions and experience their relationship with their mentors ...
Aufsatz
Chitosan hydrogels enriched with bioactive phloroglucinol for controlled drug diffusion and potential wound healing
(2024-04)
We report a facile strategy to prepare chitosan (CS) hydrogels that eliminates the need for chemical crosslinking for advanced biomedical therapies. This approach gives controlled properties to the hydrogels by incorporating a natural bioactive phenolic compound, phloroglucinol (PG), into their microstructure. The adsorption of PG onto CS chains enhanced the hydrogels' antioxidant activity by up to 25 % and resulted in a denser, more entangled structure, reducing the pore size by 59 μm while maintaining porosity above ...
Aufsatz
High-Throughput Alloy Development Using Advanced Characterization Techniques During Directed Energy Deposition Additive Manufacturing
(2023-03-31)
In laser-based direct energy deposition (DED-LB) additive manufacturing (AM), wire or powder materials are melted by a high-power laser beam. Process-specific characteristics enable robust in situ fabrication of compositionally graded materials, e.g., through an adaption of powder mass flow from independent hoppers. Based on the high flexibility of this approach, pathways toward multimaterial AM have been unlocked. Obviously, such characteristics enable high-throughput alloy development. However, rapid alloy development ...
Aufsatz
Solar driven liquid desiccant dehumidification system: Measurements and annual system simulations
(2024-01-17)
Liquid desiccant air conditioning (LDAC) systems are used for dehumidification of air to low dew point temperatures. In the presented study a TRNSYS model of a LDAC unit is developed and validated with laboratory measurements. This model is coupled with a solar thermal system that provides heating water for the regeneration process. With this model dynamic annual system simulations can be carried out to simulate the dehumidification of a building. The solar fraction is evaluated for various infiltration rates of the ...
Aufsatz
Organic Matter Matters—The Imaginary Conductivity of Sediments Rich in Solid Organic Carbon
(2023-12-01)
Solid organic matter (OM) is a biogeochemically relevant constituent of soils and sediments. It also affects sediments' geophysical properties, but is often overlooked in hydro- and biogeophysical approaches for the characterization of the shallow subsurface. Here, we explore the potential of spectral induced polarization (SIP) to delineate OM-rich zones in the subsurface and provide insights into the mechanisms that drive OM-polarization using measurements on both field cores and artificial OM-sand mixtures. Both, ...
Aufsatz
Renewable energy as an alternative source for energy management in agriculture
(2023-07-03)
This study provides a high-level overview of alternative energy sources that can be harnessed to power agricultural operations, focusing on renewable energy technologies. When thinking about the overall economy around the globe, agriculture is vital. Energy is required at each step of production, from fertilizer production to fueling tractors for planting and harvesting. The high energy prices and unpredictable energy market significantly affect the input energy costs. Energy efficiency methods, when properly applied, ...
Aufsatz
Bedeutende Städte jenseits der Metropolen? Regiopolen und ihre Rolle im deutschen Städtesystem
(2022-11-10)
Regiopolen und Regiopolregionen erfahren eine bisher kaum dagewesene Aufmerksamkeit in der deutschen Raumordnungspolitik. Neben der Förderung des deutschen RegioPole-Netzwerks durch den Bund sind Regiopolen und Regiopolregionen bereits in mehreren Raumordnungsplänen ausgewiesen. Im wissenschaftlichen Diskurs werden Regiopolen hingegen kaum aufgegriffen. Das zeigt sich insbesondere daran, dass zwar mit Dimensionen wie Stadtgröße (mehr als 100.000 Einwohner) und räumlicher Lage (außerhalb der Metropolregionen) operiert ...
Aufsatz
Water quality footprint of agricultural emissions of nitrogen, phosphorus and glyphosate associated with German bioeconomy
(2023-11-02)
Fertiliser and pesticide application can cause extensive environmental damage. We use the water quality footprint to express nitrogen, phosphorus and glyphosate emissions from agriculture in volumes of water needed to virtually dilute pollution and apply the approach to agricultural imports for the German bioeconomy in 1995 and 2020. In total, the virtual German water quality footprint corresponds to 90 times the volume of Lake Constance. If water pollution had to be eliminated by dilution in export countries supplying ...
Aufsatz
Systems methods for analyzing trade‑offs between food security and conserving biodiversity
(2023-04-15)
The endeavor for greater food security has caused trade-offs between increasing agricultural production and conserving habitat of threatened species. We take a novel approach to analyze these trade-offs by applying and comparing three systems methods (systems diagrams, influence matrices, and land use modeling) in a case study of Uganda. The first two methods were used to scope out the trade-off system and identify the most important variables influencing trade-offs. These variables were agricultural yield, land ...
Aufsatz
Optimization of the bicinchoninic acid assay for quantifying carbohydrates of soil extracellular polymeric substances
(2023-12-23)
Background and aims
The bicinchoninic acid (BCA) method was not yet applied on soil extracts of extracellular polymeric substances (EPS) to quantify polysaccharides, although this might be possible by introducing a cleavage step to produce monosaccharides. A pre-extraction with CaCl₂ to remove interfering substances is usually performed before extracting EPS. The main objective of this study was to optimize the BCA assay for total carbohydrates quantification by applying a hydrolysis step to the EPS extracts, while ...