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Aufsatz
Daniel, Ute: Beziehungsgeschichten. Politik und Medien im 20. Jahrhundert, 464 S., Hamburger Edition, Hamburg 2018.
(2020-05-07)
Er brauche zum Regieren nur „Bild, BamS und die Glotze“, so ein oft kolportiertes, wenngleich nie bestätigtes Zitat vom vermeintlichen Medienkanzler Gerhard Schröder. Die Lektüre von Ute Daniels Buch über das Verhältnis von Politik und Medien hätte ihn möglicherweise eines Besseren belehren und ihm deutlich machen können, dass die Dinge dann doch etwas komplizierter liegen. Denn, so eine zentrale Botschaft des Buches, Allmachtsfantasien erscheinen in dem komplexen Beziehungsgewirr von Politik und Medien in der einen ...
Aufsatz
Fully Implicit RUNGE-KUTTA Schemes for Ideal Elastoplasticity
(2021-12-14)
The present paper derives a multifield formulation of ideal elastoplasticity to enable the consistent application of higher order accurate RUNGE-KUTTA schemes. With the help of an axisymmetric model problem the appearing time discretization errors of distinct schemes are determined and compared.
Aufsatz
Synthesis, Structure and Cu-Phenylacetylide Coordination of an Unsymmetrically Substituted Bulky dppf-Analog
(2021-12-03)
The donor properties of a set of bulky ferrocene based bisphosphanes (Fe(C₅H₄PMes₂)₂ and (C₅H₄PMes₂)Fe(C₅H₄PᵗBu₂ with Mes= mesityl and ᵗBu=tert-butyl) were probed by exploring the NMR parameters of the corresponding selenophosphoranes amended by cyclovoltammetry. The ligand properties were explored in the complexation of copper phenylacetylide which is relevant as intermediate in the Cu(I) catalyzed CO₂ addition to phenylacetylene. Owing to the poor solubility of the resulting complexes their characterization was ...
Aufsatz
The impact of livestock grazing and canopy gaps on species pool and functional diversity of ground flora in the Caspian beech forests of Iran
(2021-06-05)
Questions
Livestock grazing is an important disturbance in many forest ecosystems. While several studies have addressed the general impact of different grazing and light intensities on temperate forest ecosystems, little is known about how the combination of these two factors can affect the species pool and functional diversity of temperate forests.
Location
Oriental beech forests of northern Iran.
Methods
Vegetation and environmental data of 104 relevés were collected. These were assigned to four groups based ...
Aufsatz
Agro-ecological landuse transformation in oasis systems of Al Jabal Al Akhdar, northern Oman
(2021-04-08)
The millenia-old oasis systems in the Western Hajar Mountains of Northern Oman have received widespread attention as models of sustainable irrigated agriculture in hyperarid Arabia. Given Oman’s rampant urbanization, growing scarcity of water and skilled labour, we quantified chances in water use, land use, and land cover between 2007 and 2018 using a rare time-series approach of detailed GIS-based crop mapping. Results from satellite image analysis and comprehensive ground truthing showed that urban areas grew from ...
Aufsatz
Evidence of considerable C and N transfer from peas to cereals via direct root contact but not via mycorrhiza
(2021-06-01)
Intercropping of legumes and cereals is an important management method for improving yield stability, especially in organic farming systems. However, knowledge is restricted on the relevance of different nutrient transfer pathways. The objective of the study was to quantify nitrogen (N) and carbon (C) transfer from peas to triticale by (1) direct root contact (= R), (2) arbuscular mycorrhizal fungi (AMF; = A), and (3) diffusion (= D). Pea (Pisum sativum cv. Frisson and P2) and triticale (Triticum × Secale cv. Benetto) ...
Aufsatz
Single-atom heat engine as a sensitive thermal probe
(2020-09-09)
We propose employing a quantum heat engine as a sensitive probe for thermal baths. In particular, we study a single-atom Otto engine operating in an open thermodynamic cycle. Owing to its cyclic nature, the engine is capable of translating small temperature differences between two baths into a macroscopic oscillation in a flywheel. We present analytical and numerical modeling of the quantum dynamics of the engine and estimate it to be capable of detecting temperature differences as small as 2 μK. This sensitivity can ...
Aufsatz
Microstructural and mechanical properties of dissimilar nitinol and stainless steel wire joints produced by micro electron beam welding without filler material
(2020-09-18)
Nitinol is a shape memory and superelastic alloy, respectively, and stainless steels are widely used materials in medical engineering, e.g., for implants and medical instruments. However, due to its high price and poor machinability, there is a high demand for dissimilar welding of nitinol components to stainless steel. During welding of titanium-containing alloys, like nitinol, to ferrous metals like stainless steel, intermetallic phases between titanium and iron may form. These phases are brittle and lead to rapid ...
Aufsatz
Deutungen von Bildung frühpädagogischer Fachkräfte
(2021-08-20)
Kindertageseinrichtungen gelten als Bildungsinstitutionen und leisten einen wesentlichen Beitrag zur Gestaltung des Aufwachsens von Kindern in Deutschland. Dabei spielen die frühpädagogischen Fachkräfte als Gestalter_innen und Ermöglicher_innen von Bildungsprozessen für Kinder eine entscheidende Rolle. Der Beitrag nimmt ihre Vorstellungen von Bildung und worauf sich diese gründen in den Blick.
Aufsatz
Detecting Careless Responding in Survey Data Using Stochastic Gradient Boosting
(2021-04-19)
Careless responding is a bias in survey responses that disregards the actual item content, constituting a threat to the factor structure, reliability, and validity of psychological measurements. Different approaches have been proposed to detect aberrant responses such as probing questions that directly assess test-taking behavior (e.g., bogus items), auxiliary or paradata (e.g., response times), or data-driven statistical techniques (e.g., Mahalanobis distance). In the present study, gradient boosted trees, a ...