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The Internal Structure of the Velvet Worm Projectile Slime: A Small-Angle Scattering Study
(2023-02-24)
For prey capture and defense, velvet worms eject an adhesive slime which has been established as a model system for recyclable complex liquids. Triggered by mechanical agitation, the liquid bio-adhesive rapidly transitions into solid fibers. In order to understand this mechanoresponsive behavior, here, the nanostructural organization of slime components are studied using small-angle scattering with neutrons and X-rays. The scattering intensities are successfully described with a three-component model accounting for ...
Aufsatz
Course characteristics influencing students’ oral participation in higher education
(2022-11-21)
Many teachers strive for lively student participation in class. This field study examined aspects of learning environments in higher education with regard to their connection with students’ oral engagement. Overall, six factors that might increase or decrease oral participation were investigated: the number of teacher questions, course atmosphere, level of demand, student preparation (e.g., through homework), class size, and subject discipline. The sample consisted of 80 courses of diverse disciplines at a public ...
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Photoelectron circular dichroism of a model chiral anion
(2022-01-18)
Photoelectron circular dichroism (PECD) in the one-photon detachment of a model chiral anionic system is studied theoretically by the single center method. The computed chiral asymmetry, characterized by the dichroic parameter β1 of up to about ±3%, is in good accord with the first experimental observations of the effect in photodetachment of amino acid anions [P. Krüger and K. M. Weitzel, Angew. Chem., Int. Ed. 60, 17861 (2021)]. Our findings confirm a general assumption that the magnitude of PECD is governed by the ...
Aufsatz
Mapping redistribution in terms of family: A European comparison
(2023-04-24)
Redistribution is one of the fundamental characteristics of developed societies. While societal redistribution between working and non-working citizens has been studied intensively, redistribution in terms of family has been analysed mainly as private redistribution. In this contribution, we study societal redistribution in terms of family by systematically analysing its regulation and simulating its results. We map family-related redistribution in Europe by analysing to whom financial resources are granted (benefits) ...
Aufsatz
Modeling and numerical simulation of flow processes of wood-polymer composites
(2023-05-31)
The combination of natural fibers and polymers is finding expanding application in a range of industrial branches, and knowledge of the material behavior is essential for further improving the products and the processing procedure. In this work, the material behavior of wood-polymer composites (WPC) will be modeled and numerical simulations will be used to investigate the flow behavior. By means of rheological measurements, a shear thinning flow behavior of the composite can be determined, which is also often taken ...
Aufsatz
Internal prestressing of ultra-high performance concrete using shape memory fibers
(2023-05-31)
Using shape memory fibers to reinforce concrete is a novel concept in civil engineering. Pre-stretched fibers are brought into concrete and after activating the shape memory effect, a compressive prestress state is introduced. The present work investigates this method numerically. A brief introduction to the relevant behavior of shape memory alloys is given. Fiber activation is modeled by an empirical phase transition model. Simulations are carried out by applying the Finite Element Method to solve the CAUCHY-FOURIER ...
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Optimal attitude maneuvers in the presence of prohibited directions
(2023-05-31)
We consider the problem of realigning a space telescope from one observation target to the next in the presence of prohibited directions. More specifically, we want to steer the space telescope – modelled as a gyrostat – from an initial attitude at rest to a final attitude at rest within a fixed time interval. During the motion, the line of sight of the telescope must be kept away from forbidden directions towards bright objects like the sun, moon or earth due to power or thermal requirements. The kinematics of the ...
Aufsatz
Influence of Mean Stress on Lifetime Prediction of Adhesive Bonds
(2023-05-31)
The importance of adhesive bonds in the field of joining technology is increasing due to their advantageous properties. One of these attributes is the possibility to reduce the weight compared to welded joints in group of components. For a safe design, the knowledge of the lifetime of these components is essential. Various methods are used for the prediction of the lifetime under cyclic loading. On the one hand there are test-based methods, on the other hand simulation-based approaches. Test-based ones are often ...
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Blood in milk in horned dairy cows–Exploration of incidences and prevention opportunities
(2023-07-20)
Husbandry of horned cows is one alternative to disbudding that respects the animals´ integrity. Concurrently, housing and management should be aligned with the animals' needs to minimize social interactions that can result in integument damage (ID) and udder injuries associated with blood in milk (BM). No information is available on incidences of BM, nor on specific preventive measures. Thus, this study aimed at investigating BM incidences in horned herds and testing whether compliance with guideline recommendations ...
Aufsatz
Impact of bias correction on climate change signals over central Europe and the Iberian Peninsula
(2023-07-27)
Vegetation models for climate adaptation and mitigation strategies require spatially high-resolution climate input data in which the error with respect to observations has been previously corrected. To quantify the impact of bias correction, we examine the effects of quantile-mapping bias correction on the climate change signal (CCS) of climate, extremes, and biological variables from the convective regional climate model COSMO-CLM and two dynamic vegetation models (LPJ-GUESS and CARAIB). COSMO-CLM was driven and ...