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Dairy Cows Are Limited in Their Ability to Increase Glucose Availability for Immune Function during Disease
(2023-03-12)
Simple Summary
Both immune defense and milk synthesis require large amounts of energy, particularly from glucose, resulting in competition between these functions if glucose availability is limited. Based on comprehensive data on cow nutrient intake and on cow health records, the magnitudes and dynamics of glucose and energy balances of dairy cows kept on an experimental farm were evaluated in the weeks before, of, and after a production disease was diagnosed. Because dry matter intake (DMI) decreased during the ...
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Tailoring flow behavior and heat transfer in tempering channels for high-pressure die casting—analysis of potentials of commercial static mixers and prospects of additive manufacturing
(2023-02-16)
Additive manufacturing (AM) opens up manifold possibilities to influence the heat transfer between fluid and die in high-pressure die casting (HPDC), eventually allowing to minimize the total cycle time of the process. AM already has been exploited to establish near-contour temperature control systems in industrial applications. However, AM not only allows to influence the position of tempering channels in dies but it also allows to influence the fluid dynamics itself, e.g., by imprinted static mixers. Up to now, ...
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Weathering of a Polyurethane-Based Gel Electrolyte
(2023-03-14)
A recently described flexible polyurethane electrolyte was artificially weathered at 25/50 °C and 50% r.h. in air and at 25 °C in a dry nitrogen atmosphere, each with and without UV irradiation. Different formulations and the polymer matrix, used as a reference, were weathered in order to investigate the influence of the amount of conductive lithium salt and the solvent propylene carbonate. The complete loss of the solvent at a standard climate was already observed after a few days, strongly influencing the ...
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Data Driven prediction of forced nonlinear vibrations using stabilised Autoregressive Neural Networks
(2023-03-24)
In this work, we propose a novel approach to the data-driven prediction of vibration responses of nonlinear systems. The main idea is based on Autoregressive Neural Networks (ARNN) to model the nonlinear transfer behaviour between an external excitation and the system response. We propose an autoregressive network architecture with embedded symmetry using bias-free tanh activation and guarantee Input-to-State-Stability (ISS) by enforcing a special penalty term to the weights. The resulting training procedure is ...
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An Investigation on Limiting Potentials for Damage Prediction of Viscoelastic Adhesives
(2023-03-24)
In his recent work VOLOKH introduced the energy limiting method as an alternative to continuum damage mechanics developed and envolved by KACHANOV, RABOTNOV, LEMAITRE and many more. In contrast to continuum damage mechanics, the energy limiting method is physically grounded by the process of atomistic debonding and, therefore, motivated on an energy basis. In order to use the energy limiting method within the framework of continuum mechanics, a limiting potential needs to be defined, which can be seen as a macroscopic ...
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Consideration of nonlinear multipoint constraints in finite element analyses based on a master-slave elimination scheme operating at the global level
(2023-03-24)
A method to consider nonlinear multipoint constraints in finite element analysis based on a master-slave elimination scheme operating at the global level is presented. We focus on systems with nonlinear constraints in which the number of constraints is of the same order of magnitude as the number of degrees of freedom. Therefore, we rely on the master-slave elimination which gives us the huge benefit of drastically reducing the problem size. In the literature the presented master-slave elimination schemes for linear ...
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Influence of Accelerated Aging on the Fiber-Matrix Adhesion of Regenerated Cellulose Fiber-Reinforced Bio-Polyamide
(2023-03-23)
With regard to the sustainability and biological origin of plastic components, regenerated cellulose fiber (RCF)-reinforced polymers are expected to replace other composites in the future. For use under severe conditions, for example, as a housing in the engine compartment, the resistance of the composites and the impact on the fiber and fiber-matrix adhesion must be investigated. Composites of bio-polyamide with a reinforcement of 20 wt.% RCF were compounded using a twinscrew extruder. The test specimens were ...
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All power to the reviewers: British sociology under two-level supervision of the Research Excellence Framework
(2023-03-16)
Our study investigates the impact of the British Research Assessment Exercise in 2008 and Research Excellence Framework in 2014 on the diversity and topic structure of UK sociology departments from the perspective of habitus-field theory. Empirically, we train a Latent Dirichlet allocation on 819,673 abstracts stemming from the journals in which British sociologists submitted at least one paper in the Research Assessment Exercise 2008 or Research Excellence Framework 2014. We then employ the trained model on the 4822 ...
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Experimentelle Untersuchungen von Wärmerohrsystemen für den Einsatz in elektrischen Arbeitskraftmaschinen
(2023-03-01)
Mit dem Ziel die Effizienz elektrischer Arbeitskraftmaschinen durch ein innovatives Kühlsystem zu erhöhen, wird ein Wärmetransportsystem auf Basis von Wärmerohren entwickelt und analysiert. Die Leistungsfähigkeit des Systems bei Variation des Temperaturbereichs und des zugeführten Wärmestroms sowie der Einfluss der Rotation werden experimentell untersucht. Der Wärmewiderstand des Systems wird im Vergleich zu reiner Wärmeleitung um 98 % reduziert. Die Rotation des Systems hat keinen signifikanten Einfluss auf den ...
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Das digitale Sportangebot „Get Up – Stand Up – Move Up“ während der Covid-19-Pandemie: eine Interviewstudie mit teilnehmenden Grundschulkindern
(2023-04-18)
Die Covid-19-Pandemie führte während des zweiten Lockdowns zu einer Reduktion der körperlichen Aktivität der Kinder in Deutschland. Um den erschwerten Möglichkeiten, sich als Kind zu bewegen, etwas entgegenzusetzen, wurde ein digitales Sportangebot initiiert. Dieses nahm insbesondere die Befriedigung der psychologischen Grundbedürfnisse in den Blick und richtete sich an Kinder im Grundschulalter. Weiterhin stand die Vermittlung von Freude an der Bewegung im Fokus. Fünf bis sechs Wochen nach Projektstart wurden acht ...