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Als eine der großen Veteranenorganisationen und rechte Sammlungsbewegung war der "Stahlhelm – Bund der Frontsoldaten" ein bedeutender politischer Akteur der Weimarer Republik. Er stand in einem äußerst ambivalenten Verhältnis zum aufstrebenden Nationalsozialismus. Einerseits konkurrierten sie um die Vorherrschaft innerhalb des nationalen Lagers, andererseits erkannten beide Seiten den Nutzen einer Kooperation. Insbesondere den einfachen Stahlhelm-Mitgliedern erschien die NS-Bewegung als attraktive Alternative, die ihre Ziele zu erreichen schien. Die Konkurrenz steigerte sich 1931/32 zur erbitterten Feindschaft. Nach der Eingliederung eines Großteils der Bundesmitglieder in die SA im Jahr 1933 sah sich der Rest-Bund immer heftigeren Repressalien ausgesetzt, bevor er 1935 aufgelöst wurde. 1951 neu gegründet, konnte er nicht an seine früheren Erfolge anknüpfen. Mehrere Spaltungen beschleunigten den Niedergang der Organisation.
Bereits im vorschulischen Bereich, aber vor allem in der Grundschule entwickeln Kinder wichtige Kompetenzen für spätere Bildungsabschlüsse. Doch die Kompe-tenzunterschiede zwischen den Schüler:innen sind bereits zu Beginn der Grund-schulzeit beträchtlich. Somit kommt den Lehrkräften die überaus wichtige Aufga-be zu allen Kindern den für sie besten Bildungsweg zu ermöglichen. Um dieser Herausforderung zu begegnen, müssen Diagnostik und Förderung im Unterricht Hand in Hand gehen. Deshalb wird die Diagnosekompetenz von Lehrkräften als wichtige Voraussetzung für gelingenden Unterricht angesehen. Diese Dissertation widmet sich nun eben dieser wichtigen Kompetenz. Dabei wird sie als mehrdimen-sionales Konstrukt angesehen, zu dem neben der Beurteilung von fachlichen Kompetenzen auch die Einschätzung des Leistungsstandes und die Schlussfolge-rung hinsichtlich notwendiger Förderung im Unterricht gehören. Anhand dreier Artikel sowie ergänzender theoretischer Betrachtungen wurde die Diagnosekompe-tenz hinsichtlich möglicher Einflussfaktoren, der Bedeutung für den Unterricht sowie für die Lehrer:innenbildung untersucht.
This book provides empirical evidence that all States have a universally binding obligation to adopt national laws and international treaties to protect the marine environment, including the designation of Marine Protected Areas. Chapter by chapter this obligation is detailed, providing the foundation for holding States responsible for fulfilling this obligation. The fundamentals are analysed in a preliminary chapter, which examines the legally binding sources of the Law of the Sea as well as its historical development to help readers understand the key principles at hand.
The Law of the Sea provides more than 1000 instruments and more than 300 regulations concerning marine protection. While the scope of most treaties is limited either regarding species, regions or activities, one regulation addresses States in all waters: the obligation to protect and preserve the marine environment as stipulated under Art. 192 of the 1982 United Nations Convention on the Law of the Sea (UNCLOS). As this ‘Constitution of the Ocean’ not only contains conventional laws but also very broadly reflects pre-existing rules of customary international law, an extensive analysis of all statements made by States in the UN General Assembly, their practices, national laws and regulations as well as other public testimonials demonstrates that Art. 192 UNCLOS indeed binds the whole community of States as a rule of customary international law with an erga omnes effect. Due to the lack of any objections and its fundamental value for humankind, this regulation can also be considered a new peremptory norm of international law (ius cogens).
While the sovereign equality of States recognises States’ freedom to decide if and how to enter into a given obligation, States can also waive this freedom. If States accepted a legally binding obligation, they are thus bound to it. Concerning the specific content of Art. 192 UNCLOS, a methodical interpretation concludes that only the adoption of legislative measures (national laws and international agreements) suffices to comply with the obligation to protect and preserve the marine environment, which is confirmed by the States’ practices and relevant jurisprudence. When applied to a specific geographical area, legislative measures to protect the marine environment concur with the definition of Marine Protected Areas. Nonetheless, as the obligation applies to all waters, the Grotian principle of the freedom of the sea dictates that the restriction of activities through the designation of Marine Protected Areas, on the one hand, must be weighed against the freedoms of other States on the other. To anticipate the result: while all other rights under the UNCLOS are subject to and contingent on other regulations of the UNCLOS and international law, only the obligation to protect and preserve the marine environment is granted absolutely – and thus outweighs all other interests
Photosynthesis converts light into metabolic energy which fuels plant growth. In nature, many factors influence light availability for photosynthesis on different time scales, from shading by leaves within seconds up to seasonal changes over months. Variability of light energy supply for photosynthesis can limit a plant´s biomass accumulation. Plants have evolved multiple strategies to cope with strongly fluctuation light (FL). These range from long-term optimization of leaf morphology and physiology and levels of pigments and proteins in a process called light acclimation, to rapid changes in protein activity within seconds. Therefore, uncovering how plants deal with FL on different time scales may provide key ideas for improving crop yield. Photosynthesis is not an isolated process but tightly integrates with metabolism through mutual regulatory interactions. We thus require mechanistic understanding of how long-term light acclimation shapes both, dynamic photosynthesis and its interactions with downstream metabolism. To approach this, we analyzed the influence of growth light on i) the function of known rapid photosynthesis regulators KEA3 and VCCN1 in dynamic photosynthesis (Chapter 2-3) and ii) the interconnection of photosynthesis with photorespiration (PR; Chapter 4).
We approached topic (i) by quantifying the effect of different growth light regimes on photosynthesis and photoprotection by using kea3 and vccn1 mutants. Firstly, we found that, besides photosynthetic capacity, the activities of VCCN1 and KEA3 during a sudden high light phase also correlated with growth light intensity. This finding suggests regulation of both proteins by the capacity of downstream metabolism. Secondly, we showed that KEA3 accelerated photoprotective non-photochemical quenching (NPQ) kinetics in two ways: Directly via downregulating the lumen proton concentration and thereby de-activating pH-dependent NPQ, and indirectly via suppressing accumulation of the photoprotective pigment zeaxanthin.
For topic (ii), we analyzed the role of PR, a process which recycles a toxic byproduct of the carbon fixation reactions, in metabolic flexibility in a dynamically changing light environment. For this we employed the mutants hpr1 and ggt1 with a partial block in PR. We characterized the function of PR during light acclimation by tracking molecular and physiological changes of the two mutants. Our data, in contrast to previous reports, disprove a generally stronger physiological relevance of PR under dynamic light conditions. Additionally, the two different mutants showed pronounced and distinct metabolic changes during acclimation to a condition inducing higher photosynthetic activity. This underlines that PR cannot be regarded purely as a cyclic detoxification pathway for 2PG. Instead, PR is highly interconnected with plant metabolism, with GGT1 and HPR1 representing distinct metabolic modulators.
In summary, the presented work provides further insight into how energetic and metabolic flexibility is ensured by short-term regulators and PR during long-term light acclimation.
Hegels Phantasie
(2023)
Als »Zwischenreich«, »Drittes« oder »Mitte« bezeichnet, kommt der Imagination seit ihren Anfängen in der Antike die Rolle eines Mediums zu. Gleichzeitig bleibt ihr medialer Aspekt durchgehend ambivalent und prekär. Es ist Georg Wilhelm Friedrich Hegel, der die Imagination nicht mehr als subjektives Vermögen versteht, sondern als Kraft der »Entäußerung« und sie somit medial denkt. In einer bislang wenig beachteten Passage aus Hegels dritter Enzyklopädie von 1830 legt Ekaterina Vassilevski nicht nur die implizite Medialität der Imagination frei, sondern auch den in Hegels Denken verborgenen Begriff des Medialen.
Unveiling the Local Universe
(2023)
Krafttraining ist ein etabliertes Mittel für die Entwicklung körperlicher Fitness und sport-artspezifischer Leistungen in verschiedenen Sportarten. Dabei scheint dem Krafttraining auch im Hinblick auf den langfristigen Leistungsaufbau im Nachwuchsleistungssport Rudern eine besondere Rolle zuzukommen. Die vorliegende Arbeit widmet sich der Optimie-rung der Leistungsdiagnostik sowie der Bewertung der Effektivität von Krafttrainingsmethoden zur Verbesserung der körperlichen Fitness und der sportartspezifischen Leistung im Nachwuchsleistungsrudern.
Die erste Studie im Rahmen dieser kumulativen Arbeit beinhaltet die Analyse eines sport-artspezifischen Anforderungsprofils der Sportart Rudern. Die Studienergebnisse zeigen, dass die Energiebereitstellung im Ruderwettkampf zu einem großen Anteil aus aeroben und zu einem geringen Anteil aus anaeroben Stoffwechselprozessen erfolgt. Während der vier Phasen des rudertechnischen Leitbildes werden nahezu alle großen Muskelgruppen beansprucht. Aufgrund der hohen Trainingsumfänge auf internationalem Leistungsniveau besteht bei Ruderern ein erhöhtes Risiko, Verletzungen im lumbalen Rückensegment, den Knien sowie den Rippen zu erleiden.
Im Rahmen der zweiten Studie wurden die Effekte von Krafttraining auf die körperliche Fitness und die sportartspezifische Leistung von Ruderern unterschiedlichen Expertisen-niveaus untersucht. Die Studienergebnisse zeigen, dass signifikante kleine Effekte des Krafttrainings auf die körperliche Fitness (Maximalkraft der unteren Gliedmaßen) und auf die sportartspezifische Leistung existieren. Subgruppenanalysen für Krafttrainingstyp und Expertisenniveau zeigten nicht signifikante Unterschiede zwischen den jeweiligen Subgruppen der Ruderer.
Die dritte Studie analysierte die Zusammenhänge zwischen der biologischen Reife, der Körperkonstitution und der körperlichen Fitness mit der Leistung auf dem Ruderergometer über 700-m bei weiblichen Nachwuchseliteruderern. Die Analyse zeigte signifikante mittle-re bis hohe Zusammenhänge zwischen der biologischen Reife, Kennwerten der Körperkonstitution, der körperlichen Fitness (z. B. Maximalkraft, Kraftausdauer) und der Leistung auf dem Ruderergometer. Zusätzlich konnte gezeigt werden, dass die Prädiktoren Körperkonstitution (Magermasse) und Kraftausdauer (Bourban-Test) die Leistung des 700-m Ruderergometertest am besten abbilden.
Die vierte Studie untersuchte die Effekte von zwei unterschiedlichen Krafttrainingsmetho-den, die jeweils über neun Wochen durchgeführt wurden, auf die körperliche Fitness und die Leistung auf dem Ruderergometer bei weiblichen Elite-Nachwuchsruderern. Die Stu-dienergebnisse zeigen, dass beide Gruppen signifikante Steigerungen auf ausgewählte Komponenten der körperlichen Fitness (z. B. Maximalkraft, Schnellkraft, anaerobe Aus-dauer und Richtungswechselgeschwindigkeit) und die sportartspezifische Leistung erzielten. Signifikant größere Zuwächse resultierten nach Krafttraining mit höheren Intensitäten [HI] bei gleichem Volumen im Vergleich zu Kraftausdauertraining [KA] in ausgewählten Komponenten der körperlichen Fitness (z. B. Maximalkraft). Im Gegensatz dazu, führte KA bei gleichem Volumen im Vergleich zu HI zu größeren Steigerungen der sportartspezifischen Leistung.
Zusammenfassend zeigen die Ergebnisse, dass Krafttraining ein effektives Mittel zur Steigerung ausgewählter Komponenten der körperlichen Fitness und der sportartspezifischen Leistung in der Sportart Rudern für RuderInnen und im Speziellen für den Nachwuchssport ist. Insbesondere im Nachwuchsleistungsrudern zeigte sich, dass HI zusätzlich zum regulären Rudertraining effektiver zur Verbesserung der körperlichen Fitness (z. B. Maximalkraft) ist als KA. Zur Verbesserung der sportartspezifischen Leistung jedoch, stellte KA im Vergleich zu HI bei weiblichen Elite-Nachwuchsruderern die effektivere Krafttrainings-methode dar. Weiterhin wird Trainern im Nachwuchsrudersport empfohlen, ausgewählte Merkmale der biologischen Reife, Körperkonstitution sowie der körperlichen Fitness (Maximalkraft, Kraftausdauer) für die Talententwicklung zu berücksichtigen.
The digitization has permeated almost all aspects of an individual’s life. In the work context as well as in the private sphere, one readily encounters and relies on Information and Communication Technologies (ICTs), such as Social Networking Sites (SNS), smartphones and so forth. By communicating with as well as obtaining information via such technologies, ICTs engage one’s mind as interaction happens. This interaction of ICTs and the human mind form the focal topic of this thesis. Within this thesis, the human mind is represented on behalf of a facilitated model comprising a perceptual, a cognitive and a motor subsystem. ICTs represent an external stimulus, which triggers the human mind's perceptual subsystem, the cognitive subsystem and eventually leads to a motoric response via the motor subsystem. The external stimulus causing this event chain is within this thesis an ICT. The digital environment and related ICTs are high attention environments offering large and easily accessible amounts of information. Not surprisingly, issues may arise, when the human mind deals with ICTs. Thus, the interplay between ICTs and the human mind entails downsides. This thesis investigates these downsides and in addition the ICT-based factors that cause these downsides. More specifically, the thesis investigates these two aspects as research questions in the context of SNSs as well as other ICTs (such as smartphones, e-learning etc.). Addressing the research questions, 8 articles are submitted within this thesis which address the topic with different methodologies, including quantitative, qualitative, mixed methods as well as systematic literature reviews. Article 1 investigates factors that lead to SNS fatigue and discontinuance intentions in a mixed-methods design. Article 2 explores if certain factors encountered on a newsfeed hamper sensemaking. Article 3 proposes a study design to explore the link between disorderly perceptions of a SNSs newsfeed and gender stereotype activations. Article 4 considers the interplay between users and algorithms via the newsfeed interface and the implications for relevance perceptions. Article 5 explores information acquisition, hampering factors and verification strategies of social media users. Article 6 systematically reviews addiction scales of various ICTs. Article 7 investigates click behavior in e-learning contexts and how this is linked to cultural and personality traits. Finally, article 8 offers a comprehensive overview of the antecedents and consequences of children’s smartphone usage. Within the specific context of SNSs, the thesis suggests that the cognitive tolls imposed on users’ minds cause adverse effects, such as impaired sensemaking, fatigue, stereotype activation as well as intentions to discontinue the service. Other ICTs lead to addiction, and i.e., smartphones evidence to cause cognitive impairments in children. Factors on the ICT side that promote these adverse effects are linked to specific features, such as the newsfeed for SNSs and entail overload or perceptions of disorder. The thesis adds theoretically to the understanding of downsides that arise from the interplay between human minds and ICTs. Especially, the context of SNSs is spotlighted and insights add to the growing body of literature on experiences and perceptions. For instance, one study’s result suggests that considering information organization is as important as merely decreasing overload perceptions from the users in countering adverse effects of SNS usage. Practically, the thesis emphasizes the importance of mindful interaction with ICTs. Future research is welcome to build on the exploratory investigations and may draw an even more holistic picture to enhance the interaction between ICTs and the human mind.
Functional materials, also called "Smart Materials", are described by their ability to fulfill a desired task through targeted interaction with its environment. Due to this functional integration, such materials are of increased interest, especially in areas where the increasing micronization of components is required. Modern manufacturing processes (e.g. microfluidics) and the availability of a wide variety of functional materials (e.g. shape memory materials) now enable the production of particle-based switching components. This category includes micropumps and microvalves, whose basic function is the active control of liquid flows. One approach in realizing those microcomponents as pursued by this work, enables variable size-switching of water-filled microballoons by implementing a stimulus-sensitive switching motif in the capsule's membrane shell, while being under the influence of a constant driving force. The switching motif with its gatekeeper function has a critical influence on one or more material parameters, which modulate the capsule's resistance against the driving force in microballoon expansion process. The advantage of this concept is that even non-variable analyte conditions, such as concentration levels of ions, can be capitalized to generate external force fields that, under the control of the membrane, cause an inflation of the microballoon by an osmotically driven water influx. In case of osmotic pressure gradients as the driving force for the capsule expansion, material parameters associated with the gatekeeper function are specifically the permeability and the mechanical stiffness of the shell material. While a modulation of the shell permeability could be utilized to kinetically impede the water influx on large time scales, a modulation of the shell's mechanical stiffness even might be utilized to completely prevent the capsule inflation due to a possible non-deformability beneath a certain threshold pressure. In polymer networks, which are a suitable material class for the demanded capsule shell because of their excellent elasticity, both the permeability and the mechanical properties are strongly influenced by the crystallinity of the material. Since the permeability is effectively reduced with increasing crystallinity, while the mechanical stiffness is simultaneously greatly increased, both effects point in the same direction in terms of their functional relationship. For this reason and due to a reversible and contactless modulation of the membrane crystallinity by heat input, crystallites may be suitable switching motifs for controlling the capsule expansion. As second design element of reversible expandable microballoons, the capsule geometry, defined by an aqueous core enveloped by the temperature-sensitive polymer network membrane, should allow an osmotic pressure gradient across the membrane layer. The strength of the inflation pressure and the associated inflation velocity upon membrane melting should be controlled by the salt concentration within the aqueous core, while a turn in the osmotic gradient should furthermore allow the reversible process of capsule deflation. Therefore, it should be possible to build either microvalves and micropumps, while their intended action of either pumping or valving is determined by their state of expansion and the direction of the osmotic pressure gradient.. Microballoons of approximately 300 µm in diameter were formed via droplet-based microfluidics from double-emulsion templates (w/o/w). The elastomeric capsule membrane was formed by photo-crosslinking of methacrylate (MA) functionalized oligo(ε-caprolactone) precursors (≈ 3.8 MA-arms, Mn ≈ 12000 g mol-1) within the organic medium layer (o) via UV-exposure after droplet-formation. After removal of the toluene/chloroform mixture by slow extraction via the continuous aqueous phase, the capsules solidified under the development of a characteristic "mushroom"-like shape at specific experimental conditions (e.g. λ = 308 nm, 57 mJ·s-1·cm-2, 16 min). It could be furthermore shown that in dependency to the process parameters: oligomer concentration and curing-time also spherical capsules were accessible. Long curing-times and high oligomer concentrations at a fixed light-intensity favored the formation of "mushroom"-like capsules, whereas the contrary led to spherical shaped capsules. A comparative study on thin polymer network films of same composition and equal treatment proved a correlation between the film's crosslink density and their contraction capability, while stronger crosslinked polymer networks showed a stronger contraction after solvent removal. In combination with observations during capsule solidification via light-microscopy, where a continuous shaping from almost spherical crosslinked templates to "mushroom"-shaped and solidified capsules was stated, the following mechanism was proposed. In case of low oligomer contents and short curing-times, the contraction of the capsule shell during solvent removal is strongly diminished due to a low degree of crosslinking. Therefore, the solidifying shell could freely collapse onto the aqueous core. In the other case, high oligomer concentrations and long curing-times will favor the formation of highly crosslinked capsule membranes with a strong contraction capability. Due to an observed decentered location of the aqueous core within the swollen polymer network, an uneven radial stress along the capsule's circumference is exerted to the incompressible core. This lead to an uneven contraction during solvent removal and a directed flow of the core fluid into the direction of the minimal stress vector. In consequence, the initially thicker spherical cap contracts, whereas the opposing thinner spherical cap get stretched. The "mushroom"-shape over some advantages over their spherical shaped counterparts, why they were selected for the further experiments. Besides the necessity of a high density of crosslinking for the purpose of extraordinary elasticity and toughness, the form-anisotropy promotes a faster microballoon expandability due to a partial reduction of the membrane thickness. Additionally, pre-stretched regions of thin thickness might provide a better resistance against inflation pressure than spherical but non-stretched capsules of equal membrane thickness. The resulting "mushroom"-shaped microcapsules exhibited a melting point of Tm ≈ 50 - 60 °C and a degree of crystallinity of Xc ≈ 29 - 38 % depending on the membrane thickness and internal salt content, which is slightly lower than for the non-crosslinked oligomer and reasoned by a limited chain mobility upon crosslinking. Nonetheless, the melting transition of the polymer network was associated with a strong drop in its mechanical stiffness, which was shown to have a strong influence on the osmotic driven expansion of the microcapsules. Capsules that were subjected to osmotic pressures between 1.5 and 4.7 MPa did not expand if the temperature was well below the melting point of the capsule's membrane, i.e. at room temperature. In contrast, a continuous expansion, while approaching asymptotically to a final capsule size, was observed if the temperature exceeded the melting point, i.e. 60 °C. Microballoons, which were kept for 56 days at ∆Π = 1.5 MPa and room temperature, did not change significantly in diameter, why the impact of the mechanical stiffness on the expansion behavior is considered to be the greater than the influence of the shell permeability. The time-resolved expansion behavior of the microballoons above their Tm was subsequently modeled, using difusion equations that were corrected for shape anisotropy and elastic restoring forces. A shape-related and expansion dependent pre-factor was used to dynamically address the influence of the shell thickness differences along the circumference on the inflation velocity, whereas the microballoon's elastic contraction upon inflation was rendered by the inclusion of a hyperelastic constitutive model. An important finding resulting from this model was the pronounced increase in inflation velocity compared to hypothetical capsules with a homogeneous shell thickness, which stresses the benefit of employing shape anisotropic balloon-like capsules in this study. Furthermore, the model was able to predict the finite expandability on basis of entropy-elastic recovery forces and strain-hardening effects. A comparison of six different microballoons with different shell thicknesses and internal salt contents showed the linear relationship between the volumetric expansion, the shell thickness and the applied osmotic pressure, as represented by the model. As the proposed model facilitates the prediction of the expansion kinetics depending on the membranes mechanical and diffusional characteristics, it might be a screening tool for future material selections. In course of the microballoon expansion process, capsules of intermediate diameters could be isolated by recrystallization of the membrane, which is mainly caused by a restoration of the membrane's mechanical stiffness and is otherwise difficult to achieve with other stimuli-sensitive systems. The capsule's crystallinity of intermediate expansion states was nearly unchanged, whereas the lamellar crystal size tends to decreased with the expansion ratio. Therefore, it was assumed that the elastic modulus was only minimally altered and might increased due to the networks segment-chain extension. In addition to the volume increase achieved by inflation, a turn in the osmotic gradient also facilitated the reversible deflation, which was shown in inflation/deflation cycles. These both characteristics of the introduced microballoons are important parameter regarding the realization of micropumps and microvalves. The fixation of expanded microcapsules via recrystallization enabled the storage of entropy-elastic strain-energy, which could be utilized for pumping actions in non-aqueous media. Here, the pumping velocity depended on both, the type of surrounding medium and the applied temperature. Surrounding media that supported the fast transport of pumped liquid showed an accelerated deflation, while high temperatures further accelerate the pumping velocity. Very fast rejection of the incorporated payload was furthermore realized with pierced expanded microballoons, which were subjected to temperatures above their Tm. The possible fixation of intermediate particle sizes provide opportunities for vent constructions that allowed the precise adjustment of specific flow-rates and multiple valve openings and closings. A valve construction was realized by the insertion of a single or multiple microballoons in a microfluidic channel. A complete and a partial closing of the microballoon-valves was demonstrated as a function of the heating period. In this context, a difference between the inflation and deflation velocity was stated, summarizing slower expansion kinetics. Overall, microballoons, which presented both on-demand pumping and reversible valving by a temperature-triggered change in the capsule's volume, might be suitable components that help to design fully integrated LOC devices, due to the implementation of the control switch and controllable inflation/deflation kinetics. In comparison to other state of the art stimuli-sensitive materials, one has to highlight the microballoons capability of stabilizing almost continuously intermediate capsule sizes by simple recrystallization of the microballoon's membrane.