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Kein anderer Akteur prägte die ersten Dezennien der Preußischen Seehandlung so sehr wie Carl August von Struensee. Als deren Direktor und dann als preußischer Finanzminister initiierte er zwischen 1782 und seinem Tod im Jahr 1804 bereits maßgeblich den langen Transformationsprozess der Seehandlung vom königlichen Wachs- und Salzmonopol hin zu einer Staatsbank, der erst im 20. Jahrhundert zum Abschluss kommen sollte. In dem Beitrag wird Struensee sowohl als Wirtschaftstheoretiker in den ökonomischen Diskursen der Aufklärung zwischen Physiokratie und Frühliberalismus situiert als auch als ein Finanzpolitiker mit konsequent europäischem Handlungshorizont vor dem Hintergrund einer beschleunigten globalen und kolonialen Mächtekonkurrenz porträtiert.
Das Jahr 1772
(2023)
Im Jahr 1772 beschäftigten drei Dinge, die lange Zeit ihre Bedeutung behalten sollten, den preußischen König Friedrich den Großen. Zunächst war dies die Adelsrepublik Polen. Polen beabsichtigte er zusammen mit der Zarin Katharina II. von Russland und Kaiserin Maria Theresia zu zerteilen. Dies geschah am 5. August des Jahres. Der geraubte Landgewinn führte bei Friedrich II. zu wirtschaftlichen Überlegungen. Mit und in den annektierten Gebieten wollte er den preußischen Handel intensivieren, zuvörderst den Salzhandel, und zwar am liebsten mit Spanien, einem Land, mit dem er schon seit geraumer Zeit versuchte, einen Handelsvertrag abzuschließen. Dazu gründete er u. a. die Preußische Seehandlungs-Gesellschaft, die, um sich zu behaupten, verschiedene weitreichende Privilegien erhielt. Ein schneller Erfolg der Bemühungen blieb jedoch aus. Trotz aller gewährten Privilegien florierten die Geschäfte der Seehandlungs-Gesellschaft in den ersten Jahren nach ihrer Gründung nicht in dem erhofften Maß. Zu Lebzeiten des Königs kam auch kein Handelsvertrag mit Spanien zustande. Bis die Seehandlung durch die Vorteile, die sie aus dem annektierten Polen ziehen konnte, profitierte, dauerte es noch einige Jahre.
Die Königlich Preußische Seehandlung, nach der heute die „Stiftung Preußische Seehandlung“ benannt ist, besitzt eine lange und vielseitige Geschichte. Der anlässlich des Stiftungsjubiläums erscheinende Band wirft einen Blick auf die Gründungskonstellation 1772, als König Friedrich II. die Gewerbe in Preußen fördern wollte. Er zeichnet die Aktivitäten von Männern an der Spitze der Seehandlung nach, wie Finanzminister Carl August von Struensee und dem unternehmerisch denkenden Karrierebeamten Christian Rother. Das Gebäude der Seehandlung wurde nach 1900 neu erbaut und ist heute in der Berlin-Brandenburgischen Akademie am Gendarmenmarkt lebendige Gegenwart. Die Seehandlung erhielt von ihren Zeitgenossen im 19. Jahrhundert ambivalente Urteile. Ein Ausblick auf die Geschichte der Stiftung Preußische Seehandlung seit 1983 zeigt das Bemühen um Kunst- und Kulturförderung als zentrale Aufgabe.
The Andean Cordillera is a mountain range located at the western South American margin and is part of the Eastern- Circum-Pacific orogenic Belt. The ~7000 km long mountain range is one of the longest on Earth and hosts the second largest orogenic plateau in the world, the Altiplano-Puna plateau. The Andes are known as a non-collisional subduction-type orogen which developed as a result of the interaction between the subducted oceanic Nazca plate and the South American continental plate. The different Andean segments exhibit along-strike variations of morphotectonic provinces characterized by different elevations, volcanic activity, deformation styles, crustal thickness, shortening magnitude and oceanic plate geometry. Most of the present-day elevation can be explained by crustal shortening in the last ~50 Ma, with the shortening magnitude decreasing from ~300 km in the central (15°S-30°S) segment to less than half that in the southern part (30°S-40°S). Several factors were proposed that might control the magnitude and acceleration of shortening of the Central Andes in the last 15 Ma. One important factor is likely the slab geometry. At 27-33°S, the slab dips horizontally at ~100 km depth due to the subduction of the buoyant Juan Fernandez Ridge, forming the Pampean flat-slab. This horizontal subduction is thought to influence the thermo-mechanical state of the Sierras Pampeanas foreland, for instance, by strengthening the lithosphere and promoting the thick-skinned propagation of deformation to the east, resulting in the uplift of the Sierras Pampeanas basement blocks. The flat-slab has migrated southwards from the Altiplano latitude at ~30 Ma to its present-day position and the processes and consequences associated to its passage on the contemporaneous acceleration of the shortening rate in Central Andes remain unclear. Although the passage of the flat-slab could offer an explanation to the acceleration of the shortening, the timing does not explain the two pulses of shortening at about 15 Ma and 4 Ma that are suggested from geological observations. I hypothesize that deformation in the Central Andes is controlled by a complex interaction between the subduction dynamics of the Nazca plate and the dynamic strengthening and weakening of the South American plate due to several upper plate processes. To test this hypothesis, a detailed investigation into the role of the flat-slab, the structural inheritance of the continental plate, and the subduction dynamics in the Andes is needed. Therefore, I have built two classes of numerical thermo-mechanical models: (i) The first class of models are a series of generic E-W-oriented high-resolution 2D subduction models thatinclude flat subduction in order to investigate the role of the subduction dynamics on the temporal variability of the shortening rate in the Central Andes at Altiplano latitudes (~21°S). The shortening rate from the models was then validated with the observed tectonic shortening rate in the Central Andes. (ii) The second class of models are a series of 3D data-driven models of the present-day Pampean flat-slab configuration and the Sierras Pampeanas (26-42°S). The models aim to investigate the relative contribution of the present-day flat subduction and inherited structures in the continental lithosphere on the strain localization. Both model classes were built using the advanced finite element geodynamic code ASPECT.
The first main finding of this work is to suggest that the temporal variability of shortening in the Central Andes is primarily controlled by the subduction dynamics of the Nazca plate while it penetrates into the mantle transition zone. These dynamics depends on the westward velocity of the South American plate that provides the main crustal shortening force to the Andes and forces the trench to retreat. When the subducting plate reaches the lower mantle, it buckles on it-self until the forced trench retreat causes the slab to steepen in the upper mantle in contrast with the classical slab-anchoring model. The steepening of the slab hinders the trench causing it to resist the advancing South American plate, resulting in the pulsatile shortening. This buckling and steepening subduction regime could have been initiated because of the overall decrease in the westwards velocity of the South American plate. In addition, the passage of the flat-slab is required to promote the shortening of the continental plate because flat subduction scrapes the mantle lithosphere, thus weakening the continental plate. This process contributes to the efficient shortening when the trench is hindered, followed by mantle lithosphere delamination at ~20 Ma. Finally, the underthrusting of the Brazilian cratonic shield beneath the orogen occurs at ~11 Ma due to the mechanical weakening of the thick sediments covered the shield margin, and due to the decreasing resistance of the weakened lithosphere of the orogen.
The second main finding of this work is to suggest that the cold flat-slab strengthens the overriding continental lithosphere and prevents strain localization. Therefore, the deformation is transmitted to the eastern front of the flat-slab segment by the shear stress operating at the subduction interface, thus the flat-slab acts like an indenter that “bulldozes” the mantle-keel of the continental lithosphere. The offset in the propagation of deformation to the east between the flat and steeper slab segments in the south causes the formation of a transpressive dextral shear zone. Here, inherited faults of past tectonic events are reactivated and further localize the deformation in an en-echelon strike-slip shear zone, through a mechanism that I refer to as “flat-slab conveyor”. Specifically, the shallowing of the flat-slab causes the lateral deformation, which explains the timing of multiple geological events preceding the arrival of the flat-slab at 33°S. These include the onset of the compression and of the transition between thin to thick-skinned deformation styles resulting from the crustal contraction of the crust in the Sierras Pampeanas some 10 and 6 Myr before the Juan Fernandez Ridge collision at that latitude, respectively.
The knowledge of transformation pathways and identification of transformation products (TPs) of veterinary drugs is important for animal health, food, and environmental matters. The active agent Monensin (MON) belongs to the ionophore antibiotics and is widely used as a veterinary drug against coccidiosis in broiler farming. However, no electrochemically (EC) generated TPs of MON have been described so far. In this study, the online coupling of EC and mass spectrometry (MS) was used for the generation of oxidative TPs. EC-conditions were optimized with respect to working electrode material, solvent, modifier, and potential polarity. Subsequent LC/HRMS (liquid+ chromatography/high resolution mass spectrometry) and MS/MS experiments were performed to identify the structures of derived TPs by a suspected target analysis. The obtained EC-results were compared to TPs observed in metabolism tests with microsomes and hydrolysis experiments of MON. Five previously undescribed TPs of MON were identified in our EC/MS based study and one TP, which was already known from literature and found by a microsomal assay, could be confirmed. Two and three further TPs were found as products in microsomal tests and following hydrolysis, respectively. We found decarboxylation, O-demethylation and acid-catalyzed ring-opening reactions to be the major mechanisms of MON transformation
Dermal Delivery of the High-Molecular-Weight Drug Tacrolimus by Means of Polyglycerol-Based Nanogels
(2019)
Polyglycerol-based thermoresponsive nanogels (tNGs) have been shown to have excellent skin hydration properties and to be valuable delivery systems for sustained release of drugs into skin. In this study, we compared the skin penetration of tacrolimus formulated in tNGs with a commercial 0.1% tacrolimus ointment. The penetration of the drug was investigated in ex vivo abdominal and breast skin, while different methods for skin barrier disruption were investigated to improve skin permeability or simulate inflammatory conditions with compromised skin barrier. The amount of penetrated tacrolimus was measured in skin extracts by liquid chromatography tandem-mass spectrometry (LC-MS/MS), whereas the inflammatory markers IL-6 and IL-8 were detected by enzyme-linked immunosorbent assay (ELISA). Higher amounts of tacrolimus penetrated in breast as compared to abdominal skin or in barrier-disrupted as compared to intact skin, confirming that the stratum corneum is the main barrier for tacrolimus skin penetration. The anti-proliferative effect of the penetrated drug was measured in skin tissue/Jurkat cells co-cultures. Interestingly, tNGs exhibited similar anti-proliferative effects as the 0.1% tacrolimus ointment. We conclude that polyglycerol-based nanogels represent an interesting alternative to paraffin-based formulations for the treatment of inflammatory skin conditions.
Der Bereich der grenzüberschreitenden Daseinsvorsorge ist eines der zentralen Potentialfelder in der Grenzüberschreitenden Zusammenarbeit. Grenzüberschreitende Daseinsvorsorge kann ein wesentliches Element zur Verbesserung der Lebensverhältnisse in Grenzregionen sein.
Bei der Umsetzung von Projekten im diesem Bereich sind – sofern der politische Wille hierfür vorhanden ist – erhebliche rechtliche Hürden zu überwinden: Zwar existieren passend ausgerichtete europäische Fördermittelprogramme als Anreiz, andererseits scheinen die europarechtlichen und nationalrechtlichen Rahmenbedingungen vielfach hochgradig komplex und können auch mit europarechtlichen Instrumenten, etwa dem Europäischen Verbund für territoriale Zusammenarbeit (EVTZ), kaum überwunden werden.
Der vorliegende Text analysiert am Beispiel der deutsch-polnischen die rechtlichen Schwierigkeiten, aber auch die Möglichkeiten zur Umsetzung grenzüberschreitender Projekte in diesem Bereich.
We investigate whether political ideology has an observable effect on decarbonization ambition, renewable power aims, and preferences for power system balancing technologies in four European countries. Based on the Energy Logics framework, we identify ideologically different transition strategies (state-centered, market-centered, grassroots-centered) contained in government policies and opposition party programs valid in 2019. We compare these policies and programs with citizen poll data. We find that ideology has a small effect: governments and political parties across the spectrum have similar, and relatively ambitious, decarbonization and renewables targets. This mirrors citizens' strong support for ambitious action regardless of their ideological self-description. However, whereas political positions on phasing out fossil fuel power are clear across the policy space, positions on phasing in new flexibility options to balance intermittent renewables are vague or non-existent. As parties and citizens agree on strong climate and renewable power aims, the policy ambition is likely to remain high, even if governments change.
Prediction of hybrid biomass in Arabidopsis thaliana by selected parental SNP and metabolic markers
(2009)
A recombinant inbred line (RIL) population, derived from two Arabidopsis thaliana accessions, and the corresponding testcrosses with these two original accessions were used for the development and validation of machine learning models to predict the biomass of hybrids. Genetic and metabolic information of the RILs served as predictors. Feature selection reduced the number of variables (genetic and metabolic markers) in the models by more than 80% without impairing the predictive power. Thus, potential biomarkers have been revealed. Metabolites were shown to bear information on inherited macroscopic phenotypes. This proof of concept could be interesting for breeders. The example population exhibits substantial mid-parent biomass heterosis. The results of feature selection could therefore be used to shed light on the origin of heterosis. In this respect, mainly dominance effects were detected.
In recent decades, astronomy has seen a boom in large-scale stellar surveys of the Galaxy. The detailed information obtained about millions of individual stars in the Milky Way is bringing us a step closer to answering one of the most outstanding questions in astrophysics: how do galaxies form and evolve? The Milky Way is the only galaxy where we can dissect many stars into their high-dimensional chemical composition and complete phase space, which analogously as fossil records can unveil the past history of the genesis of the Galaxy. The processes that lead to large structure formation, such as the Milky Way, are critical for constraining cosmological models; we call this line of study Galactic archaeology or near-field cosmology.
At the core of this work, we present a collection of efforts to chemically and dynamically characterise the disks and bulge of our Galaxy. The results we present in this thesis have only been possible thanks to the advent of the Gaia astrometric satellite, which has revolutionised the field of Galactic archaeology by precisely measuring the positions, parallax distances and motions of more than a billion stars. Another, though not less important, breakthrough is the APOGEE survey, which has observed spectra in the near-infrared peering into the dusty regions of the Galaxy, allowing us to determine detailed chemical abundance patterns in hundreds of thousands of stars. To accurately depict the Milky Way structure, we use and develop the Bayesian isochrone fitting tool/code called StarHorse; this software can predict stellar distances, extinctions and ages by combining astrometry, photometry and spectroscopy based on stellar evolutionary models. The StarHorse code is pivotal to calculating distances where Gaia parallaxes alone cannot allow accurate estimates.
We show that by combining Gaia, APOGEE, photometric surveys and using StarHorse, we can produce a chemical cartography of the Milky way disks from their outermost to innermost parts. Such a map is unprecedented in the inner Galaxy. It reveals a continuity of the bimodal chemical pattern previously detected in the solar neighbourhood, indicating two populations with distinct formation histories. Furthermore, the data reveals a chemical gradient within the thin disk where the content of 𝛼-process elements and metals is higher towards the centre. Focusing on a sample in the inner MW we confirm the extension of the chemical duality to the innermost regions of the Galaxy. We find stars with bar shape orbits to show both high- and low-𝛼 abundances, suggesting the bar formed by secular evolution trapping stars that already existed. By analysing the chemical orbital space of the inner Galactic regions, we disentangle the multiple populations that inhabit this complex region. We reveal the presence of the thin disk, thick disk, bar, and a counter-rotating population, which resembles the outcome of a perturbed proto-Galactic disk. Our study also finds that the inner Galaxy holds a high quantity of super metal-rich stars up to three times solar suggesting it is a possible repository of old super-metal-rich stars found in the solar neighbourhood.
We also enter into the complicated task of deriving individual stellar ages. With StarHorse, we calculate the ages of main-sequence turn-off and sub-giant stars for several public spectroscopic surveys. We validate our results by investigating linear relations between chemical abundances and time since the 𝛼 and neutron capture elements are sensitive to age as a reflection of the different enrichment timescales of these elements. For further study of the disks in the solar neighbourhood, we use an unsupervised machine learning algorithm to delineate a multidimensional separation of chrono-chemical stellar groups revealing the chemical thick disk, the thin disk, and young 𝛼-rich stars. The thick disk is shown to have a small age dispersion indicating its fast formation contrary to the thin disk that spans a wide range of ages.
With groundbreaking data, this thesis encloses a detailed chemo-dynamical view of the disk and bulge of our Galaxy. Our findings on the Milky Way can be linked to the evolution of high redshift disk galaxies, helping to solve the conundrum of galaxy formation.
Dieser Beitrag beschäftigt sich mit einer problematischen Seite der Samen- und Eizellenspende. Konkret konzentriert er sich auf die Anonymität im Rahmen dieses Verfahrens, die in manchen europäischen Staaten als eine gesetzliche Bedingung festgelegt ist. Es geht um eine Konsequenz der unklaren Regulierung auf EU-Ebene, die es ermöglicht, nationale Vorschriften nach individuellen Präferenzen des Gesetzgebers zu konzipieren. Trotzdem muss auch der menschenrechtliche Kontext berücksichtigt werden, weil die Anonymität des:der Spender:in dazu führt, dass das Kind de facto keine Chancen hat, seine (genetischen oder biologischen) Eltern zu kennen. Im Prinzip verletzt ein solcher Ansatz das Recht des Kindes auf Kenntnis der eigenen Abstammung, das in entsprechenden Menschenrechtskonventionen verankert und in der Judikatur des EGMR interpretiert wurde.
Das Vorsorgeprinzip ist ein mittlerweile weit verbreiteter und etablierter Grundsatz des internationalen und europäischen Umweltrechts. Demnach sollen auch in Situationen wissenschaftlicher Unsicherheit präventive Maßnahmen ergriffen werden, um schwerwiegende Umweltschäden zu vermeiden. Dieser Beitrag untersucht die Rolle des Vorsorgeprinzips im Zusammenhang mit menschenrechtlichen Klimaklagen, die aufgrund langsamer politischer Fortschritte und erfolgreicher Gerichtsentscheidungen zunehmend an Popularität gewinnen.
Zunächst wird ein Überblick über die Entwicklung und den materiellen Gehalt des Vorsorgeprinzips im internationalen und europäischen Recht gegeben. Obwohl das Vorsorgeprinzip seit den 1980er Jahren ein fixer Bestandteil des internationalen Umweltrechts ist, bestehen über dessen genauen Inhalt und Rechtsnatur nach wie vor Kontroversen. Im Unionsrecht wurde das Vorsorgeprinzip insbesondere durch die Rechtsprechung des EuGH konkretisiert.
Im nächsten Teil des Beitrags wird beleuchtet, welche Bedeutung der EGMR dem Vorsorgeprinzip in umweltrechtlichen Fällen bisher zugemessen hat. Hierbei steht die Entscheidung Tǎtar gegen Rumänien im Mittelpunkt. Gegenstand dieser Entscheidung war der Goldabbau in der rumänischen Stadt Baia Mare, der unter anderem unter dem Einsatz von Natriumzyanid erfolgte und zu wesentlichen Schadstoffbelastungen führte. Der EGMR bejahte unter Verweis auf das Vorsorgeprinzip eine Verletzung von Art. 8 EMRK, obwohl der Beschwerdeführer die Kausalität zwischen der Schadstoffbelastung und der behaupteten Schädigung nicht nachweisen konnte. Eine Analyse der nachfolgenden Entscheidungen veranschaulicht jedoch, dass sich das Vorsorgeprinzip noch nicht als fixer Bestandteil in der Rechtsprechung des EGMR etablieren konnte.
Abschließend wird gezeigt, welchen Beitrag das Vorsorgeprinzip zu der bisher wohl erfolgreichsten Klimaklage „Urgenda“ leistete. Das Vorsorgeprinzip wurde vom niederländischen Höchstgericht in diesem Fall insbesondere herangezogen, um Schutzpflichten aus Art. 2 und Art. 8 EMRK abzuleiten und den staatlichen Ermessenspielraum einzuschränken.
Spätestens seit dem Brand einer Textilfabrik in Karatschi, Pakistan, deren Hauptabnehmer das deutsche Textilunternehmen KiK war, ist die Frage nach der zivilrechtlichen Justiziabilität von Menschenrechtsverletzungen im Ausland auch in der Bundesrepublik angekommen. Parallel hierzu hatte bereits der Einsturz des Rana Plaza, einem Fabrikgebäude in Dhaka, Bangladesch, das zahlreiche Zulieferfirmen der europäischen sowie u.s.-amerikanischen Bekleidungsindustrie beherbergte, traurige Berühmtheit erlangt. Beide Vorfälle hatten in den Industriestaaten des globalen Nordens eine nachhaltige Debatte darüber ausgelöst, welche Verantwortung inländischen Abnehmerunternehmen für die Einhaltung internationaler Menschenrechtsstandards entlang der global angelegten Lieferkette zukommt. An deren vorläufigem Ende steht eine Reihe von Spezialgesetzen, die heimischen Betrieben ausdifferenzierte Sorgfalts- und Überwachungspflichten bezüglich der Arbeitsbedingungen in den – häufig im globalen Süden gelegenen – Produktionsstätten auferlegen.
Als Folge dieses geostrategischen Nord-Süd-Konfliktes wohnt in Deutschland erhobenen Menschenrechtsklagen im Regelfall ein grenzüberscheitendes Moment inne, weshalb sich die Rechtsverfolgung individuell Betroffener mit den Fragen des Internationalen Privatrechts nach der gerichtlichen Zuständigkeit sowie des anwendbaren Sachrechts konfrontiert sieht. Dass ein Verfahren bereits auf dieser Ebene scheitern kann, verdeutlicht auf paradigmatische Weise das eingangs erwähnte Verfahren gegen KiK vor dem LG Dortmund, in welchem das ungünstige pakistanische Verjährungsrecht zur Anwendung gelangte.
Rechtspolitisch wird die Funktion des Rechtsgebietes indes unterschiedlich beurteilt. Während ein Ansatz gleichsam auf materieller Ebene die Entwicklung spezieller Sorgfaltsnormen für Unternehmen in Abnehmerstaaten verfolgt („Verantwortungslösung“), führt eine andere Auffassung den Kern der Problematik nicht auf das – oftmals durchaus funktionale – Produktionslandrecht, sondern vielmehr auf dessen strukturelle Durchsetzungsdefizite zurück („Kognitionslösung“).
Der Beitrag vollzieht die Implikationen beider Ansätze für Zivilprozesse in Deutschland nach. Hierfür wird die Menschenrechtsklage zunächst in das deutsche Verfahrensrecht eingeordnet (I.) bevor die Rolle des Internationalen Privatrechtes erörtert werden kann (II.). Anschließend werden sowohl die Sorgfaltsregime in den Abnehmerstaaten (III.) als auch Rechtsbehelfe in den Produktionsländern am Beispiel Bangladeschs (IV.) in den Blick genommen.
Aus dem Inhalt:
- Menschenrechtsklagen vor Zivilgerichten in Deutschland – Eine Bestandsaufnahme der methodisch-rechtspolitischen Ansätze im Internationalen Privatrecht (IPR)
- Das Vorsorgeprinzip – ein unterschätzter Bestandteil menschenrechtlicher Klimaklagen?
- Der Menschenrechtsausschuss der Vereinten Nationen und die Klimakrise – Die Entscheidung Billy et al. gegen Australien und ihr Beitrag zur „Begrünung“ des Menschenrechtsschutzes
Inverted perovskite solar cells still suffer from significant non-radiative recombination losses at the perovskite surface and across the perovskite/C₆₀ interface, limiting the future development of perovskite-based single- and multi-junction photovoltaics. Therefore, more effective inter- or transport layers are urgently required. To tackle these recombination losses, we introduce ortho-carborane as an interlayer material that has a spherical molecular structure and a three-dimensional aromaticity. Based on a variety of experimental techniques, we show that ortho-carborane decorated with phenylamino groups effectively passivates the perovskite surface and essentially eliminates the non-radiative recombination loss across the perovskite/C₆₀ interface with high thermal stability. We further demonstrate the potential of carborane as an electron transport material, facilitating electron extraction while blocking holes from the interface. The resulting inverted perovskite solar cells deliver a power conversion efficiency of over 23% with a low non-radiative voltage loss of 110 mV, and retain >97% of the initial efficiency after 400 h of maximum power point tracking. Overall, the designed carborane based interlayer simultaneously enables passivation, electron-transport and hole-blocking and paves the way toward more efficient and stable perovskite solar cells.
Intuitively, strongly constraining contexts should lead to stronger probabilistic representations of sentences in memory. Encountering unexpected words could therefore be expected to trigger costlier shifts in these representations than expected words. However, psycholinguistic measures commonly used to study probabilistic processing, such as the N400 event-related potential (ERP) component, are sensitive to word predictability but not to contextual constraint. Some research suggests that constraint-related processing cost may be measurable via an ERP positivity following the N400, known as the anterior post-N400 positivity (PNP). The PNP is argued to reflect update of a sentence representation and to be distinct from the posterior P600, which reflects conflict detection and reanalysis. However, constraint-related PNP findings are inconsistent. We sought to conceptually replicate Federmeier et al. (2007) and Kuperberg et al. (2020), who observed that the PNP, but not the N400 or the P600, was affected by constraint at unexpected but plausible words. Using a pre-registered design and statistical approach maximising power, we demonstrated a dissociated effect of predictability and constraint: strong evidence for predictability but not constraint in the N400 window, and strong evidence for constraint but not predictability in the later window. However, the constraint effect was consistent with a P600 and not a PNP, suggesting increased conflict between a strong representation and unexpected input rather than greater update of the representation. We conclude that either a simple strong/weak constraint design is not always sufficient to elicit the PNP, or that previous PNP constraint findings could be an artifact of smaller sample size.
Technologically important, environmentally friendly InP quantum dots (QDs) typically used as green and red emitters in display devices can achieve exceptional photoluminescence quantum yields (PL QYs) of near-unity (95-100%) when the-state-of-the-art core/shell heterostructure of the ZnSe inner/ZnS outer shell is elaborately applied. Nevertheless, it has only led to a few industrial applications as QD liquid crystal display (QD–LCD) which is applied to blue backlight units, even though QDs has a lot of possibilities that able to realize industrially feasible applications, such as QD light-emitting diodes (QD‒LEDs) and luminescence solar concentrator (LSC), due to their functionalizable characteristics.
Before introducing the main research, the theoretical basis and fundamentals of QDs are described in detail on the basis of the quantum mechanics and experimental synthetic results, where a concept of QD and colloidal QD, a type-I core/shell structure, a transition metal doped semiconductor QDs, the surface chemistry of QD, and their applications (LSC, QD‒LEDs, and EHD jet printing) are sequentially elucidated for better understanding. This doctoral thesis mainly focused on the connectivity between QD materials and QD devices, based on the synthesis of InP QDs that are composed of inorganic core (core/shell heterostructure) and organic shell (surface ligands on the QD surface). In particular, as for the former one (core/shell heterostructure), the ZnCuInS mid-shell as an intermediate layer is newly introduced between a Cu-doped InP core and a ZnS shell for LSC devices. As for the latter one (surface ligands), the ligand effect by 1-octanethiol and chloride ion are investigated for the device stability in QD‒LEDs and the printability of electro-hydrodynamic (EHD) jet printing system, in which this research explores the behavior of surface ligands, based on proton transfer mechanism on the QD surface.
Chapter 3 demonstrates the synthesis of strain-engineered highly emissive Cu:InP/Zn–Cu–In–S (ZCIS)/ZnS core/shell/shell heterostructure QDs via a one-pot approach. When this unconventional combination of a ZCIS/ZnS double shelling scheme is introduced to a series of Cu:InP cores with different sizes, the resulting Cu:InP/ZCIS/ZnS QDs with a tunable near-IR PL range of 694–850 nm yield the highest-ever PL QYs of 71.5–82.4%. These outcomes strongly point to the efficacy of the ZCIS interlayer, which makes the core/shell interfacial strain effectively alleviated, toward high emissivity. The presence of such an intermediate ZCIS layer is further examined by comparative size, structural, and compositional analyses. The end of this chapter briefly introduces the research related to the LSC devices, fabricated from Cu:InP/ZCIS/ZnS QDs, currently in progress.
Chapter 4 mainly deals with ligand effect in 1-octanethiol passivation of InP/ZnSe/ZnS QDs in terms of incomplete surface passivation during synthesis. This chapter demonstrates the lack of anionic carboxylate ligands on the surface of InP/ZnSe/ZnS quantum dots (QDs), where zinc carboxylate ligands can be converted to carboxylic acid or carboxylate ligands via proton transfer by 1-octanethiol. The as-synthesized QDs initially have an under-coordinated vacancy surface, which is passivated by solvent ligands such as ethanol and acetone. Upon exposure of 1-octanethiol to the QD surface, 1-octanthiol effectively induces the surface binding of anionic carboxylate ligands (derived from zinc carboxylate ligands) by proton transfer, which consequently exchanges ethanol and acetone ligands that bound on the incomplete QD surface. The systematic chemical analyses, such as thermogravimetric analysis‒mass spectrometry and proton nuclear magnetic resonance spectroscopy, directly show the interplay of surface ligands, and it associates with QD light-emitting diodes (QD‒LEDs).
Chapter 5 shows the relation between material stability of QDs and device stability of QD‒LEDs through the investigation of surface chemistry and shell thickness. In typical III–V colloidal InP quantum dots (QDs), an inorganic ZnS outermost shell is used to provide stability when overcoated onto the InP core. However, this work presents a faster photo-degradation of InP/ZnSe/ZnS QDs with a thicker ZnS shell than that with a thin ZnS shell when 1-octanethiol was applied as a sulfur source to form ZnS outmost shell. Herein, 1-octanethiol induces the form of weakly-bound carboxylate ligand via proton transfer on the QD surface, resulting in a faster degradation at UV light even though a thicker ZnS shell was formed onto InP/ZnSe QDs. Detailed insight into surface chemistry was obtained from proton nuclear magnetic resonance spectroscopy and thermogravimetric analysis–mass spectrometry. However, the lifetimes of the electroluminescence devices fabricated from InP/ZnSe/ZnS QDs with a thick or a thin ZnS shell show surprisingly the opposite result to the material stability of QDs, where the QD light-emitting diodes (QD‒LEDs) with a thick ZnS shelled QDs maintained its luminance more stable than that with a thin ZnS shelled QDs. This study elucidates the degradation mechanism of the QDs and the QD light-emitting diodes based on the results and discuss why the material stability of QDs is different from the lifetime of QD‒LEDs.
Chapter 6 suggests a method how to improve a printability of EHD jet printing when QD materials are applied to QD ink formulation, where this work introduces the application of GaP mid-shelled InP QDs as a role of surface charge in EHD jet printing technique. In general, GaP intermediate shell has been introduced in III–V colloidal InP quantum dots (QDs) to enhance their thermal stability and quantum efficiency in the case of type-I core/shell/shell heterostructure InP/GaP/ZnSeS QDs. Herein, these highly luminescent InP/GaP/ZnSeS QDs were synthesized and applied to EHD jet printing, by which this study demonstrates that unreacted Ga and Cl ions on the QD surface induce the operating voltage of cone jet and cone jet formation to be reduced and stabilized, respectively. This result indicates GaP intermediate shell not only improves PL QY and thermal stability of InP QDs but also adjusts the critical flow rate required for cone-jet formation. In other words, surface charges of quantum dots can have a significant role in forming cone apex in the EHD capillary nozzle. For an industrially convenient validation of surface charges on the QD surface, Zeta potential analyses of QD solutions as a simple method were performed, as well as inductively coupled plasma optical emission spectrometry (ICP-OES) for a composition of elements.
Beyond the generation of highly emissive InP QDs with narrow FWHM, these studies talk about the connection between QD material and QD devices not only to make it a vital jumping-off point for industrially feasible applications but also to reveal from chemical and physical standpoints the origin that obstructs the improvement of device performance experimentally and theoretically.
Desperados at Sea
(2023)
Pirates are fortune-seeking fighters at sea. Their exploits fire the imaginations of their victims and admirers, drawing a veil over individuals who rarely bear a real name and pursue their adventurous occupations as buccaneers, filibusters, freebooters, privateers, pirates, or corsairs. Piracy, corsairing, and contraband trade were epidemic among the Egyptians and the Phoenicians, the Greeks and the Vikings, the Spaniards and the Ottomans, the Muslims, and the Christians. And the Jews.
Jacob Brandon Maduro’s Memoirs and Related Observations (Havana, 1953) speak to the lasting yet malleable legacy of Jewish Caribbean/Atlantic mercantile communities that defined early modern settlement in the Americas. A close reading of the Memoirs, alongside relevant archival records and community narratives, lends new perspectives to scholarship on Port Jewries and the Atlantic Diaspora. Specifically concerned with Jacob’s adoption of such leading intellectual and political tropes as the Monroe doctrine, José Martí’s Nuestra America, and a Zionism that evolved from an ideology to a reality, the Memoirs reveal a narrative at once defined by the tremendous upheavals of the first half of the 20th century, and an enduring sense of Jewish diasporic peoplehood defined through a Port Jew paradigm whereby the preservation of Jewish ethnicity is understood as synonymous with the championing of modernity.
“Creating a Maritime Future”
(2023)
This article explores the importance of the port city of Hamburg in the evolving discourses on the creation of a maritime future, a vision which became influential in the 1930s, 1940s and 1950s. While some Jewish representatives in the city aimed at preserving and intertwining Hanseatic and Jewish traditions in order to secure a Jewish presence in the port city under the pressure of the Nazi regime and thereafter, others wanted to create new emigration opportunities, especially to Mandatory Palestine, and create a Jewish maritime future in Eretz Israel. Different Zionist organizations supported the newly evolving maritime ideas, such as the “conquest of the sea”, and promoted the image of a Jewish seafaring nation. Despite the difficulties in the 1940s, these concepts gained influence post-1945 and led to the foundation of the fishery kibbutz “Zerubavel” in Blankenese/Hamburg. However, the idea of a Hanseatic Jewish future also remained influential and illustrates how differently a “Jewish maritime future” was imagined and used to link past, present and future.
Mothers of Seafaring
(2023)
The article aims to trace the contribution of Jewish women in the Yishuv’s maritime history. Taking the example of Henrietta Diamond, a founding member and chairperson of the Zebulun Seafaring Society, the article seeks to explore the representation and role of women in a growing Jewish maritime domain from the 1930s to the 1950s. It examines Zionist narratives on the ‘New Jew’ and the Jewish body and studies their relevance for the emerging field of maritime activities in the Yishuv. By contextualizing the work and depiction of Henrietta Diamond, the article sheds new light on the gendered notions that underlay the emergence of the Jewish maritime domain and illustrates the patterns of inclusion and exclusion in it.
The birth of the Yishuv’s national shipping company, ZIM was preceded by private enterprise; the sea had not traditionally been a focus of the Zionist movement. In the 1930s, a five-year span of private commercial shipping saw three companies in the Jewish community in Palestine – Palestine Shipping Company, Palestine Maritime Lloyd, and Atid – before shipping was cut short by the outbreak of the Second World War. Despite their brief lifespans and their negligible contribution to general shipping, these companies constituted an important milestone. Their existence helped shift the Yishuv leadership’s attitudes about shipping’s importance for the community and the need for it to be supported by national institutions.
“Israel am Meere”
(2023)
For Jews in Germany, the period following the Nazis’ rise to power in January 1933 was a period of decision-making on many levels: How should they respond to the persecution? If they decided to emigrate, many more decisions had to be made: How does one leave a country, and where should one go? A key moment in the process and in the cultural practice of emigration is the beginning of the sea voyage – when the need for departure and the hope for a new arrival jointly create a period of liminality. Looking at reports from sea voyages of exploration and emigration from the 1930s, this contribution discusses the question whether, and in what ways, such reflections can be read in the context of religious experiences and in the search for Jewish identities in times of turmoil.
The last years have been affected by Covid-19 and the international emergency mecha-nism to deal with health-related threats. The effects of this period manifested differ-ently worldwide, depending on matters such as international relations, national policies, power dynamics etc. Additionally, the impact of this time will likely have long-term effects which are yet to be known. This paper gives a critical overview of the Public Health Emergency of International Concern (PHEIC) mechanism in the context of Covid-19. It does so by explaining the legal framework for states of emergency, specifically in the context of a PHEIC, while considering its restrictions and limitations on human rights. It further outlines issues in the manifestation of global protections and limitations on human rights during Covid-19. Lastly, considering the likelihood of future PHEICs and the known systemic obstructions, this paper offers ways to im-prove this mechanism from a holistic, non-zero-sum perspective.
‚Maise Jeschurun‘
(2023)
Abgelegte Musik
(2023)
Schutz und Schaden
(2023)
Einleitung
(2023)
This dissertation aimed to determine differential expressed miRNAs in the context of chronic pain in polyneuropathy. For this purpose, patients with chronic painful polyneuropathy were compared with age matched healthy patients. Taken together, all miRNA pre library preparation quality controls were successful and none of the samples was identified as an outlier or excluded for library preparation. Pre sequencing quality control showed that library preparation worked for all samples as well as that all samples were free of adapter dimers after BluePippin size selection and reached the minimum molarity for further processing. Thus, all samples were subjected to sequencing. The sequencing control parameters were in their optimal range and resulted in valid sequencing results with strong sample to sample correlation for all samples. The resulting FASTQ file of each miRNA library was analyzed and used to perform a differential expression analysis. The differentially expressed and filtered miRNAs were subjected to miRDB to perform a target prediction. Three of those four miRNAs were downregulated: hsa-miR-3135b, hsa-miR-584-5p and hsa-miR-12136, while one was upregulated: hsa-miR-550a-3p. miRNA target prediction showed that chronic pain in polyneuropathy might be the result of a combination of miRNA mediated high blood flow/pressure and neural activity dysregulations/disbalances. Thus, leading to the promising conclusion that these four miRNAs could serve as potential biomarkers for the diagnosis of chronic pain in polyneuropathy.
Since TRPV1 seems to be one of the major contributors of nociception and is associated with neuropathic pain, the influence of PKA phosphorylated ARMS on the sensitivity of TRPV1 as well as the part of AKAP79 during PKA phosphorylation of ARMS was characterized. Therefore, possible PKA-sites in the sequence of ARMS were identified. This revealed five canonical PKA-sites: S882, T903, S1251/52, S1439/40 and S1526/27. The single PKA-site mutants of ARMS revealed that PKA-mediated ARMS phosphorylation seems not to influence the interaction rate of TRPV1/ARMS. While phosphorylation of ARMST903 does not increase the interaction rate with TRPV1, ARMSS1526/27 is probably not phosphorylated and leads to an increased interaction rate. The calcium flux measurements indicated that the higher the interaction rate of TRPV1/ARMS, the lower the EC50 for capsaicin of TRPV1, independent of the PKA phosphorylation status of ARMS. In addition, the western blot analysis confirmed the previously observed TRPV1/ARMS interaction. More importantly, AKAP79 seems to be involved in the TRPV1/ARMS/PKA signaling complex. To overcome the problem of ARMS-mediated TRPV1 sensitization by interaction, ARMS was silenced by shRNA. ARMS silencing resulted in a restored TRPV1 desensitization without affecting the TRPV1 expression and therefore could be used as new topical therapeutic analgesic alternative to stop ARMS mediated TRPV1 sensitization.
Genisa-Blätter IV
(2023)
Auch wenn Genisot – jüdische Ablagen nicht mehr verwendeter Bücher und Kultgegenstände – in der bisherigen historischen Forschung selten beachtet werden, sind sie als Quellen aus originär jüdischer Hand von hoher Bedeutung und können unser Verständnis der Umsetzung von Ritualen im Kontext der lokalen Gemeinde vertiefen.
Der Schwerpunkt der ‚Genisa-Blätter IV‘ liegt auf Fragen nach jüdisch-rituellen Praktiken und ihrer Bedeutung, ihren Objekten und Akteuren. Acht wissenschaftliche und ein essayistischer Beitrag nähern sich diesen Themen über konkrete Funde aus Genisot mitteleuropäischer jüdischer Gemeinden, von religiösen Texten wie dem Fragment einer Torarolle und einem Minhagim-Buch über Personaldokumente bis hin zu Musiknoten und Kleidungsstücken.
Under Brazil's ex-president Bolsonaro, deforestation of the Amazon increased dramatically. An Austrian NGO filed a complaint to the Prosecutor of the International Criminal Court (ICC) against Bolsonaro in October 2021, accusing him of crimes against humanity against the backdrop of his involvement in environmental destruction. This paper deals with the question of whether this initi-ative constitutes a promising means of juridification to mitigate conflicts revolving around mass deforestation in Brazil. It thematizes attempts to juridify environmental destruction in international criminal law and examines the Climate Fund Case at the Brazilian Supreme Court. Finally, emerging problems and arguments in favour of starting preliminary examinations at the ICC against Bolsonaro are illuminated. This paper provides arguments as to why the initiative might be a promising undertaking, even though it is unlikely that Bolsonaro will be arrested.
In this work, binding interactions between biomolecules were analyzed by a technique that is based on electrically controllable DNA nanolevers. The technique was applied to virus-receptor interactions for the first time. As receptors, primarily peptides on DNA nanostructures and antibodies were utilized. The DNA nanostructures were integrated into the measurement technique and enabled the presentation of the peptides in a controllable geometrical order. The number of peptides could be varied to be compatible to the binding sites of the viral surface proteins.
Influenza A virus served as a model system, on which the general measurability was demonstrated. Variations of the receptor peptide, the surface ligand density, the measurement temperature and the virus subtypes showed the sensitivity and applicability of the technology. Additionally, the immobilization of virus particles enabled the measurement of differences in oligovalent binding of DNA-peptide nanostructures to the viral proteins in their native environment.
When the coronavirus pandemic broke out in 2020, work on binding interactions of a peptide from the hACE2 receptor and the spike protein of the SARS-CoV-2 virus revealed that oligovalent binding can be quantified in the switchSENSE technology. It could also be shown that small changes in the amino acid sequence of the spike protein resulted in complete loss of binding. Interactions of the peptide and inactivated virus material as well as pseudo virus particles could be measured. Additionally, the switchSENSE technology was utilized to rank six antibodies for their binding affinity towards the nucleocapsid protein of SARS-CoV-2 for the development of a rapid antigen test device.
The technique was furthermore employed to show binding of a non-enveloped virus (adenovirus) and a virus-like particle (norovirus-like particle) to antibodies. Apart from binding interactions, the use of DNA origami levers with a length of around 50 nm enabled the switching of virus material. This proved that the technology is also able to size objects with a hydrodynamic diameter larger than 14 nm.
A theoretical work on diffusion and reaction-limited binding interactions revealed that the technique and the chosen parameters enable the determination of binding rate constants in the reaction-limited regime.
Overall, the applicability of the switchSENSE technique to virus-receptor binding interactions could be demonstrated on multiple examples. While there are challenges that remain, the setup enables the determination of affinities between viruses and receptors in their native environment. Especially the possibilities regarding the quantification of oligo- and multivalent binding interactions could be presented.
The central gas in half of all galaxy clusters shows short cooling times. Assuming unimpeded cooling, this should lead to high star formation and mass cooling rates, which are not observed. Instead, it is believed that condensing gas is accreted by the central black hole that powers an active galactic nuclei jet, which heats the cluster. The detailed heating mechanism remains uncertain. A promising mechanism invokes cosmic ray protons that scatter on self-generated magnetic fluctuations, i.e. Alfvén waves. Continuous damping of Alfvén waves provides heat to the intracluster medium. Previous work has found steady state solutions for a large sample of clusters where cooling is balanced by Alfvénic wave heating. To verify modeling assumptions, we set out to study cosmic ray injection in three-dimensional magnetohydrodynamical simulations of jet feedback in an idealized cluster with the moving-mesh code arepo. We analyze the interaction of jet-inflated bubbles with the turbulent magnetized intracluster medium.
Furthermore, jet dynamics and heating are closely linked to the largely unconstrained jet composition. Interactions of electrons with photons of the cosmic microwave background result in observational signatures that depend on the bubble content. Those recent observations provided evidence for underdense bubbles with a relativistic filling while adopting simplifying modeling assumptions for the bubbles. By reproducing the observations with our simulations, we confirm the validity of their modeling assumptions and as such, confirm the important finding of low-(momentum) density jets.
In addition, the velocity and magnetic field structure of the intracluster medium have profound consequences for bubble evolution and heating processes. As velocity and magnetic fields are physically coupled, we demonstrate that numerical simulations can help link and thereby constrain their respective observables. Finally, we implement the currently preferred accretion model, cold accretion, into the moving-mesh code arepo and study feedback by light jets in a radiatively cooling magnetized cluster. While self-regulation is attained independently of accretion model, jet density and feedback efficiencies, we find that in order to reproduce observed cold gas morphology light jets are preferred.
Das Modell Friedland
(2022)
Mit dem Band 14 „Das Modell Friedland: Vom Zusammenleben deutscher, jüdischer und wendischer Bewohner in einer Niederlausitzer Kleinstadt“ haben die Herausgeber den Autoren Alfred Roggan und Tobias Preßler die Erweiterung ihrer Forschungen ermöglicht: Widmete sich deren Band 12 „Sorbische/Wendische Spuren in der nördlichen Niederlausitz“ (2019) noch Befunden einer binationalen, weil deutsch-wendischen Geschichte, so wird mit dem Band 14 erstmalig für Ostdeutschland die Dokumentation einer ‚trinationalen‘, also deutsch-jüdisch-wendischen Lebenswelt vorgenommen.
Die Untersuchungen verdeutlichen, wie sich drei, im 18. Jahrhundert annähernd gleich große Einwohner-Gruppen, mit ihren Gotteshäusern, ihren Sprachen und einem differenzierten Einwohnerstatus etablierten bzw. arrangiert haben. Es zeigten sich Alleinstellungsmerkmale in Lebens- sowie Kultorganisation, Wirtschaftstätigkeiten und der Kommunikation zwischen den Beheimateten. Mit der Amts-Verwaltung des Johanniter-Ritterordens und dem Stadtrat befanden sie sich in berechenbaren (deutschdominierten) Strukturen. Aus diesem Gefüge und der territorialen Grenzlage zum Kurfürstentum Brandenburg begründeten sich Bedingungen, ohne die es wohl zu keinem „Modell Friedland“ gekommen wäre.
Die Autoren sind dankbar, dass sich mit Friedland die gnädige Chance bot, einen Bereich zu untersuchen, in dem Prozesse der wendisch-deutschen Assimilierung in einer eigenen Stetigkeit abliefen, jedoch das Ende jüdischen Lebens auf die Abwanderungen infolge der preußischen Emanzipations-Gesetze des 19. Jahrhunderts und nicht auf die Demütigungen, Verfolgungen sowie dem Völkermord des faschistischen deutschen Staates, zurückzuführen sind.
Facing the environmental crisis, new technologies are needed to sustain our society. In this context, this thesis aims to describe the properties and applications of carbon-based sustainable materials. In particular, it reports the synthesis and characterization of a wide set of porous carbonaceous materials with high nitrogen content obtained from nucleobases. These materials are used as cathodes for Li-ion capacitors, and a major focus is put on the cathode preparation, highlighting the oxidation resistance of nucleobase-derived materials. Furthermore, their catalytic properties for acid/base and redox reactions are described, pointing to the role of nitrogen speciation on their surfaces. Finally, these materials are used as supports for highly dispersed nickel loading, activating the materials for carbon dioxide electroreduction.
Selenium (Se) is an essential trace element that is ubiquitously present in the environment in small concentrations. Essential functions of Se in the human body are manifested through the wide range of proteins, containing selenocysteine as their active center. Such proteins are called selenoproteins which are found in multiple physiological processes like antioxidative defense and the regulation of thyroid hormone functions. Therefore, Se deficiency is known to cause a broad spectrum of physiological impairments, especially in endemic regions with low Se content. Nevertheless, being an essential trace element, Se could exhibit toxic effects, if its intake exceeds tolerable levels. Accordingly, this range between deficiency and overexposure represents optimal Se supply. However, this range was found to be narrower than for any other essential trace element. Together with significantly varying Se concentrations in soil and the presence of specific bioaccumulation factors, this represents a noticeable difficulty in the assessment of Se
epidemiological status. While Se is acting in the body through multiple selenoproteins, its intake occurs mainly in form of small organic or inorganic molecular mass species. Thus, Se exposure not only depends on daily intake but also on the respective chemical form, in which it is present.
The essential functions of selenium have been known for a long time and its primary forms in different food sources have been described. Nevertheless, analytical capabilities for a comprehensive investigation of Se species and their derivatives have been introduced only in the last decades. A new Se compound was identified in 2010 in the blood and tissues of bluefin tuna. It was called selenoneine (SeN) since it is an isologue of naturally occurring antioxidant ergothioneine (ET), where Se replaces sulfur. In the following years, SeN was identified in a number of edible fish species and attracted attention as a new dietary Se source and potentially strong antioxidant. Studies in populations whose diet largely relies on fish revealed that SeN
represents the main non-protein bound Se pool in their blood. First studies, conducted with enriched fish extracts, already demonstrated the high antioxidative potential of SeN and its possible function in the detoxification of methylmercury in fish. Cell culture studies demonstrated, that SeN can utilize the same transporter as ergothioneine, and SeN metabolite was found in human urine.
Until recently, studies on SeN properties were severely limited due to the lack of ways to obtain the pure compound. As a predisposition to this work was firstly a successful approach to SeN synthesis in the University of Graz, utilizing genetically modified yeasts. In the current study, by use of HepG2 liver carcinoma cells, it was demonstrated, that SeN does not cause toxic effectsup to 100 μM concentration in hepatocytes. Uptake experiments showed that SeN is not bioavailable to the used liver cells.
In the next part a blood-brain barrier (BBB) model, based on capillary endothelial cells from the porcine brain, was used to describe the possible transfer of SeN into the central nervous system (CNS). The assessment of toxicity markers in these endothelial cells and monitoring of barrier conditions during transfer experiments demonstrated the absence of toxic effects from SeN on the BBB endothelium up to 100 μM concentration. Transfer data for SeN showed slow but substantial transfer. A statistically significant increase was observed after 48 hours following SeN incubation from the blood-facing side of the barrier. However, an increase in Se content was clearly visible already after 6 hours of incubation with 1 μM of SeN. While the transfer rate of SeN after application of 0.1 μM dose was very close to that for 1 μM, incubation with 10 μM of SeN resulted in a significantly decreased transfer rate. Double-sided application of SeN caused no side-specific transfer of SeN, thus suggesting a passive diffusion mechanism of SeN across the BBB. This data is in accordance with animal studies, where ET accumulation was observed in the rat brain, even though rat BBB does not have the primary ET transporter – OCTN1. Investigation of capillary endothelial cell monolayers after incubation with SeN and reference selenium compounds showed no significant increase of intracellular selenium concentration. Speciesspecific Se measurements in medium samples from apical and basolateral compartments, as good as in cell lysates, showed no SeN metabolization. Therefore, it can be concluded that SeN may reach the brain without significant transformation.
As the third part of this work, the assessment of SeN antioxidant properties was performed in Caco-2 human colorectal adenocarcinoma cells. Previous studies demonstrated that the intestinal epithelium is able to actively transport SeN from the intestinal lumen to the blood side and accumulate SeN. Further investigation within current work showed a much higher antioxidant potential of SeN compared to ET. The radical scavenging activity after incubation with SeN was close to the one observed for selenite and selenomethionine. However, the SeN effect on the viability of intestinal cells under oxidative conditions was close to the one caused by ET. To answer the question if SeN is able to be used as a dietary Se source and induce the activity of selenoproteins, the activity of glutathione peroxidase (GPx) and the secretion of selenoprotein P (SelenoP) were measured in Caco-2 cells, additionally. As expected, reference selenium compounds selenite and selenomethionine caused efficient induction of GPx activity. In contrast to those SeN had no effect on GPx activity. To examine the possibility of SeN being embedded into the selenoproteome, SelenoP was measured in a culture medium. Even though Caco-2 cells effectively take up SeN in quantities much higher than selenite or selenomethionine, no secretion of SelenoP was observed after SeN incubation.
Summarizing, we can conclude that SeN can hardly serve as a Se source for selenoprotein synthesis. However, SeN exhibit strong antioxidative properties, which appear when sulfur in ET is exchanged by Se. Therefore, SeN is of particular interest for research not as part of Se metabolism, but important endemic dietary antioxidant.
Background
Animal personality has emerged as a key concept in behavioral ecology. While many studies have demonstrated the influence of personality traits on behavioral patterns, its quantification, especially in wild animal populations, remains a challenge. Only a few studies have established a link between personality and recurring movements within home ranges, although these small-scale movements are of key importance for identifying ecological interactions and forming individual niches. In this regard, differences in space use among individuals might reflect different exploration styles between behavioral types along the shy-bold continuum.
Methods
We assessed among-individual differences in behavior in the European hare (Lepus europaeus), a characteristic mammalian herbivore in agricultural landscapes using a standardized box emergence test for captive and wild hares. We determined an individuals’ degree of boldness by measuring the latencies of behavioral responses in repeated emergence tests in captivity. During capture events of wild hares, we conducted a single emergence test and recorded behavioral responses proven to be stable over time in captive hares. Applying repeated novel environment tests in a near-natural enclosure, we further quantified aspects of exploration and activity in captive hares. Finally, we investigated whether and how this among-individual behavioral variation is related to general activity and space use in a wild hare population. Wild and captive hares were treated similarly and GPS-collared with internal accelerometers prior to release to the wild or the outdoor enclosure, respectively. General activity was quantified as overall dynamic body acceleration (ODBA) obtained from accelerometers. Finally, we tested whether boldness explained variation in (i) ODBA in both settings and (ii) variation in home ranges and core areas across different time scales of GPS-collared hares in a wild population.
Results
We found three behavioral responses to be consistent over time in captive hares. ODBA was positively related to boldness (i.e., short latencies to make first contact with the new environment) in both captive and wild hares. Space use in wild hares also varied with boldness, with shy individuals having smaller core areas and larger home ranges than bold conspecifics (yet in some of the parameter space, this association was just marginally significant).
Conclusions
Against our prediction, shy individuals occupied relatively large home ranges but with small core areas. We suggest that this space use pattern is due to them avoiding risky, and energy-demanding competition for valuable resources. Carefully validated, activity measurements (ODBA) from accelerometers provide a valuable tool to quantify aspects of animal personality along the shy-bold continuum remotely. Without directly observing—and possibly disturbing—focal individuals, this approach allows measuring variability in animal personality, especially in species that are difficult to assess with experiments. Considering that accelerometers are often already built into GPS units, we recommend activating them at least during the initial days of tracking to estimate individual variation in general activity and, if possible, match them with a simple novelty experiment. Furthermore, information on individual behavioral types will help to facilitate mechanistic understanding of processes that drive spatial and ecological dynamics in heterogeneous landscapes.
Among the multitude of geomorphological processes, aeolian shaping processes are of special character, Pedogenic dust is one of the most important sources of atmospheric aerosols and therefore regarded as a key player for atmospheric processes. Soil dust emissions, being complex in composition and properties, influence atmospheric processes and air quality and has impacts on other ecosystems. In this because even though their immediate impact can be considered low (exceptions exist), their constant and large-scale force makes them a powerful player in the earth system. dissertation, we unravel a novel scientific understanding of this complex system based on a holistic dataset acquired during a series of field experiments on arable land in La Pampa, Argentina. The field experiments as well as the generated data provide information about topography, various soil parameters, the atmospheric dynamics in the very lower atmosphere (4m height) as well as measurements regarding aeolian particle movement across a wide range of particle size classes between 0.2μm up to the coarse sand.
The investigations focus on three topics: (a) the effects of low-scale landscape structures on aeolian transport processes of the coarse particle fraction, (b) the horizontal and vertical fluxes of the very fine particles and (c) the impact of wind gusts on particle emissions.
Among other considerations presented in this thesis, it could in particular be shown, that even though the small-scale topology does have a clear impact on erosion and deposition patterns, also physical soil parameters need to be taken into account for a robust statistical modelling of the latter. Furthermore, specifically the vertical fluxes of particulate matter have different characteristics for the particle size classes. Finally, a novel statistical measure was introduced to quantify the impact of wind gusts on the particle uptake and its application on the provided data set. The aforementioned measure shows significantly increased particle concentrations during points in time defined as gust event.
With its holistic approach, this thesis further contributes to the fundamental understanding of how atmosphere and pedosphere are intertwined and affect each other.
The increasing demand for energy in the current technological era and the recent political decisions about giving up on nuclear energy diverted humanity to focus on alternative environmentally friendly energy sources like solar energy. Although silicon solar cells are the product of a matured technology, the search for highly efficient and easily applicable materials is still ongoing. These properties made the efficiency of halide perovskites comparable with silicon solar cells for single junctions within a decade of research. However, the downside of halide perovskites are poor stability and lead toxicity for the most stable ones.
On the other hand, chalcogenide perovskites are one of the most promising absorber materials for the photovoltaic market, due to their elemental abundance and chemical stability against moisture and oxygen. In the search of the ultimate solar absorber material, combining the good optoelectronic properties of halide perovskites with the stability of chalcogenides could be the promising candidate.
Thus, this work investigates new techniques for the synthesis and design of these novel chalcogenide perovskites, that contain transition metals as cations, e.g., BaZrS3, BaHfS3, EuZrS3, EuHfS3 and SrHfS3. There are two stages in the deposition techniques of this study: In the first stage, the binary compounds are deposited via a solution processing method. In the second stage, the deposited materials are annealed in a chalcogenide atmosphere to form the perovskite structure by using solid-state reactions.
The research also focuses on the optimization of a generalized recipe for a molecular ink to deposit precursors of chalcogenide perovskites with different binaries. The implementation of the precursor sulfurization resulted in either binaries without perovskite formation or distorted perovskite structures, whereas some of these materials are reported in the literature as they are more favorable in the needle-like non-perovskite configuration.
Lastly, there are two categories for the evaluation of the produced materials: The first category is about the determination of the physical properties of the deposited layer, e.g., crystal structure, secondary phase formation, impurities, etc. For the second category, optoelectronic properties are measured and compared to an ideal absorber layer, e.g., band gap, conductivity, surface photovoltage, etc.
National Action Plans (NAPs) have been increas-ingly adopted world-wide after the Vienna Dec-laration in 1993, where it was urged to consider the improvement and promotion of Human Rights. In this paper, we discuss their usefulness and success by analysing the challenges present-ed during NAP processes as well as the benefits this set of actions entails: The challenges for their implementation outweigh its actual benefits. Nevertheless, NAPs have great potential. Based on new research, we elaborate a set of recom-mendations for improving the design and imple-mentation of national action planning. In order to effectively bring NAP into practice, we consider it crucial to plan and analyse every state local circumstances in detail. The latter is important, since the implementation of a concrete set of actions is intended to directly transform and improve the local living conditions of the people. In a long-term perspective, we defend the benefit of NAP’s implementation for complying obliga-tions set up by HR treaties.
Carbon dioxide removal from the atmosphere is becoming an important option to achieve net zero climate targets. This paper develops a welfare and public economics perspective on optimal policies for carbon removal and storage in non-permanent sinks like forests, soil, oceans, wood products or chemical products. We derive a new metric for the valuation of non-permanent carbon storage, the social cost of carbon removal (SCC-R), which embeds also the conventional social cost of carbon emissions. We show that the contribution of CDR is to create new carbon sinks that should be used to reduce transition costs, even if the stored carbon is released to the atmosphere eventually. Importantly, CDR does not raise the ambition of optimal temperature levels unless initial atmospheric carbon stocks are excessively high. For high initial atmospheric carbon stocks, CDR allows to reduce the optimal temperature below initial levels. Finally, we characterize three different policy regimes that ensure an optimal deployment of carbon removal: downstream carbon pricing, upstream carbon pricing, and carbon storage pricing. The policy regimes differ in their informational and institutional requirements regarding monitoring, liability and financing.
Abzug unter Beobachtung
(2022)
Mehr als vier Jahrzehnte lang beobachteten die Streitkräfte und Militärnachrichtendienste der NATO-Staaten die sowjetischen Truppen in der DDR. Hierfür übernahm in der Bundesrepublik Deutschland der Bundesnachrichtendienst (BND) die militärische Auslandsaufklärung unter Anwendung nachrichtendienstlicher Mittel und Methoden. Die Bundeswehr betrieb dagegen taktische Fernmelde- und elektronische Aufklärung und hörte vor allem den Funkverkehr der „Gruppe der sowjetischen Streitkräfte in Deutschland“ (GSSD) ab. Mit der Aufstellung einer zentralen Dienststelle für das militärische Nachrichtenwesen, dem Amt für Nachrichtenwesen der Bundeswehr, bündelte und erweiterte zugleich das Bundesministerium für Verteidigung in den 1980er Jahren seine analytischen Kapazitäten. Das Monopol des BND in der militärischen Auslandsaufklärung wurde von der Bundeswehr dadurch zunehmend infrage gestellt.
Nach der deutschen Wiedervereinigung am 3. Oktober 1990 befanden sich immer noch mehr als 300.000 sowjetische Soldaten auf deutschem Territorium. Die 1989 in Westgruppe der Truppen (WGT) umbenannte GSSD sollte – so der Zwei-plus-Vier-Vertrag – bis 1994 vollständig abziehen. Der Vertrag verbot auch den drei Westmächten, in den neuen Bundesländern militärisch tätig zu sein. Die für die Militäraufklärung bis dahin unverzichtbaren Militärverbindungsmissionen der Westmächte mussten ihre Dienste einstellen. Doch was geschah mit diesem „alliierten Erbe“? Wer übernahm auf deutscher Seite die Aufklärung der sowjetischen Truppen und wer kontrollierte den Truppenabzug?
Die Studie untersucht die Rolle von Bundeswehr und BND beim Abzug der WGT zwischen 1990 und 1994 und fragt dabei nach Kooperation und Konkurrenz zwischen Streitkräften und Nachrichtendiensten. Welche militärischen und nachrichtendienstlichen Mittel und Fähigkeiten stellte die Bundesregierung zur Bewältigung des Truppenabzugs zur Verfügung, nachdem die westlichen Militärverbindungsmissionen aufgelöst wurden? Wie veränderten sich die Anforderungen an die militärische Auslandsaufklärung des BND? Inwieweit setzten sich Konkurrenz und Kooperation von Bundeswehr und BNDbeim Truppenabzug fort? Welche Rolle spielten dabei die einstigen Westmächte? Die Arbeit versteht sich nicht nur als Beitrag zur Militärgeschichte, sondern auch zur deutschen Nachrichtendienstgeschichte.
Complex emulsions are dispersions of kinetically stabilized multiphasic emulsion droplets comprised of two or more immiscible liquids that provide a novel material platform for the generation of active and dynamic soft materials. In recent years, the intrinsic reconfigurable morphological behavior of complex emulsions, which can be attributed to the unique force equilibrium between the interfacial tensions acting at the various interfaces, has become of fundamental and applied interest. As such, particularly biphasic Janus droplets have been investigated as structural templates for the generation of anisotropic precision objects, dynamic optical elements or as transducers and signal amplifiers in chemo- and bio-sensing applications. In the present thesis, switchable internal morphological responses of complex droplets triggered by stimuli-induced alterations of the balance of interfacial tensions have been explored as a universal building block for the design of multiresponsive, active, and adaptive liquid colloidal systems. A series of underlying principles and mechanisms that influence the equilibrium of interfacial tensions have been uncovered, which allowed the targeted design of emulsion bodies that can alter their shape, bind and roll on surfaces, or change their geometrical shape in response to chemical stimuli. Consequently, combinations of the unique triggerable behavior of Janus droplets with designer surfactants, such as a stimuli-responsive photosurfactant (AzoTAB) resulted for instance in shape-changing soft colloids that exhibited a jellyfish inspired buoyant motion behavior, holding great promise for the design of biological inspired active material architectures and transformable soft robotics.
In situ observations of spherical Janus emulsion droplets using a customized side-view microscopic imaging setup with accompanying pendant dropt measurements disclosed the sensitivity regime of the unique chemical-morphological coupling inside complex emulsions and enabled the recording of calibration curves for the extraction of critical parameters of surfactant effectiveness. The deduced new "responsive drop" method permitted a convenient and cost-efficient quantification and comparison of the critical micelle concentrations (CMCs) and effectiveness of various cationic, anionic, and nonionic surfactants. Moreover, the method allowed insightful characterization of stimuli-responsive surfactants and monitoring of the impact of inorganic salts on the CMC and surfactant effectiveness of ionic and nonionic surfactants. Droplet functionalization with synthetic crown ether surfactants yielded a synthetically minimal material platform capable of autonomous and reversible adaptation to its chemical environment through different supramolecular host-guest recognition events. Addition of metal or ammonium salts resulted in the uptake of the resulting hydrophobic complexes to the hydrocarbon hemisphere, whereas addition of hydrophilic ammonium compounds such as amino acids or polypeptides resulted in supramolecular assemblies at the hydrocarbon-water interface of the droplets. The multiresponsive material platform enabled interfacial complexation and
thus triggered responses of the droplets to a variety of chemical triggers including metal ions, ammonium compounds, amino acids, antibodies, carbohydrates as well as amino-functionalized solid surfaces.
In the final chapter, the first documented optical logic gates and combinatorial logic circuits based on complex emulsions are presented. More specifically, the unique reconfigurable and multiresponsive properties of complex emulsions were exploited to realize droplet-based logic gates of varying complexity using different stimuli-responsive surfactants in combination with diverse readout methods. In summary, different designs for multiresponsive, active, and adaptive liquid colloidal systems were presented and investigated, enabling the design of novel transformative chemo-intelligent soft material platforms.
Cosmic rays (CRs) constitute an important component of the interstellar medium (ISM) of galaxies and are thought to play an essential role in governing their evolution. In particular, they are able to impact the dynamics of a galaxy by driving galactic outflows or heating the ISM and thereby affecting the efficiency of star-formation. Hence, in order to understand galaxy formation and evolution, we need to accurately model this non-thermal constituent of the ISM. But except in our local environment within the Milky Way, we do not have the ability to measure CRs directly in other galaxies. However, there are many ways to indirectly observe CRs via the radiation they emit due to their interaction with magnetic and interstellar radiation fields as well as with the ISM.
In this work, I develop a numerical framework to calculate the spectral distribution of CRs in simulations of isolated galaxies where a steady-state between injection and cooling is assumed. Furthermore, I calculate the non-thermal emission processes arising from the modelled CR proton and electron spectra ranging from radio wavelengths up to the very high-energy gamma-ray regime.
I apply this code to a number of high-resolution magneto-hydrodynamical (MHD) simulations of isolated galaxies, where CRs are included. This allows me to study their CR spectra and compare them to observations of the CR proton and electron spectra by the Voyager-1 satellite and the AMS-02 instrument in order to reveal the origin of the measured spectral features.
Furthermore, I provide detailed emission maps, luminosities and spectra of the non-thermal emission from our simulated galaxies that range from dwarfs to Milk-Way analogues to starburst galaxies at different evolutionary stages. I successfully reproduce the observed relations between the radio and gamma-ray luminosities with the far-infrared (FIR) emission of star-forming (SF) galaxies, respectively, where the latter is a good tracer of the star-formation rate. I find that highly SF galaxies are close to the limit where their CR population would lose all of their energy due to the emission of radiation, whereas CRs tend to escape low SF galaxies more quickly. On top of that, I investigate the properties of CR transport that are needed in order to match the observed gamma-ray spectra.
Furthermore, I uncover the underlying processes that enable the FIR-radio correlation (FRC) to be maintained even in starburst galaxies and find that thermal free-free-emission naturally explains the observed radio spectra in SF galaxies like M82 and NGC 253 thus solving the riddle of flat radio spectra that have been proposed to contradict the observed tight FRC.
Lastly, I scrutinise the steady-state modelling of the CR proton component by investigating for the first time the influence of spectrally resolved CR transport in MHD simulations on the hadronic gamma-ray emission of SF galaxies revealing new insights into the observational signatures of CR transport both spectrally and spatially.
Fontanes Medien
(2023)
Theodor Fontane war, im durchaus modernen Sinne, ein Medienarbeiter: Als Presse-Agent in London lernte er die innovativste Presselandschaft seiner Zeit kennen; als Redakteur in Berlin leistete er journalistische Kärrnerarbeit; er schrieb Kritiken über das Theater, die bildende Kunst und die Literatur – und auch seine Romane wie seine Reisebücher sind stets Medienprodukte, als Serien in in Zeitungen und Zeitschriften platziert, bevor sie auf dem Buchmarkt erschienen.
Der vorliegende Band dokumentiert die Ergebnisse eines internationalen Kongresses, veranstaltet 2019 vom Theodor-Fontane-Archiv in Potsdam. Die ebenso rasante wie umfassende Medialisierung und Vernetzung der Gesellschaft im Laufe des 19. Jahrhunderts wird dabei als produktive Voraussetzung der schriftstellerischen Tätigkeit Fontanes begriffen. Eingebettet in ein weit verzweigtes Netz der Korrespondenz und der postalischen Textzirkulation, vertraut mit den Routinen und Publika der periodischen Massenpresse, für die er sein Leben lang schrieb, und auf vielfältige Weise geprägt von der visuellen Kultur seiner Zeit wird Theodor Fontane als gleichermaßen journalistisch versierter wie ästhetisch sensibler Grenzgänger erkennbar.
»Ich hab eine Idee!«
(2022)
Urban pollution
(2022)
We use worldwide satellite data to analyse how population size and density affect urban pollution. We find that density significantly increases pollution exposure. Looking only at urban areas, we find that population size affects exposure more than density. Moreover, the effect is driven mostly by population commuting to core cities rather than the core city population itself. We analyse heterogeneity by geography and income levels. By and large, the influence of population on pollution is greatest in Asia and middle-income countries. A counterfactual simulation shows that PM2.5 exposure would fall by up to 36% and NO2 exposure up to 53% if within countries population size were equalized across all cities.
Indigene Rechte und COVID-19 (Brasilien) – indigenes Land und Gesundheit unter ernster Bedrohung
(2022)
Kollektiv zum Recht
(2022)
Predicting entrepreneurial development based on individual and business-related characteristics is a key objective of entrepreneurship research. In this context, we investigate whether the motives of becoming an entrepreneur influence the subsequent entrepreneurial development. In our analysis, we examine a broad range of business outcomes including survival and income, as well as job creation, expansion and innovation activities for up to 40 months after business formation. Using self-determination theory as conceptual background, we aggregate the start-up motives into a continuous motivational index. We show – based on a unique dataset of German start-ups from unemployment and non-unemployment – that the later business performance is better, the higher they score on this index. Effects are particularly strong for growth oriented outcomes like innovation and expansion activities. In a next step, we examine three underlying motivational categories that we term opportunity, career ambition, and necessity. We show that individuals driven by opportunity motives perform better in terms of innovation and business expansion activities, while career ambition is positively associated with survival, income, and the probability of hiring employees. All effects are robust to the inclusion of a large battery of covariates that are proven to be important determinants of entrepreneurial performance.
Das Praxissemester stellt eine zentrale Lerngelegenheit für Studierende dar. Im Rahmen dieser Studie wurden 6 Personen mit einem Zeitabstand von einem bis drei Jahren zu ihrem Praxissemester interviewt. Schwerpunkte der Befragung waren die wahrgenommenen Lerngelegenheiten und Lernzuwächse während des Praxissemesters und dessen retrospektive Beurteilung. Im Einklang mit anderen Studien nahmen die Befragten ihren eigenen Unterricht als wichtigste Lerngelegenheit wahr, da sie dort ihre Berufswahlentscheidung bestätigt sahen, sich im Unterrichten ausprobieren konnten und vom Feedback ihrer Schülerinnen und Schüler sowie Ausbildungslehrkräfte profitierten. Mit einem zeitlichen Abstand von einem bis drei Jahren nahmen sie das Praxissemester noch immer positiv wahr. Der Teil der Befragten, die sich zum Zeitpunkt der Befragung im Referendariat befanden, beschrieben das Praxissemester als Möglichkeit, erste Eindrücke aus dem Schulalltag zu sammeln und sich auf das Referendariat vorzubereiten.
Überzeugungen zum Lehren und Lernen sind als Teil der professionellen Kompetenz von Lehrkräften bereits im Lehramtsstudium relevant und haben insbesondere in längeren Praxisphasen Entwicklungspotenzial. Welche Faktoren für die Entwicklung von Überzeugungen in Praxisphasen von Bedeutung sind, ist bislang aber nur unzureichend erforscht. In Interviews haben wir N = 16 Studierende befragt, welche Lerngelegenheiten für die Entwicklung ihrer Überzeugungen im Praxissemester eine Rolle spielten. Dabei konnten wir mittels Inhaltsanalyse vier übergeordnete Faktoren identifizieren: die universitäre Lernbegleitung, die Mentorinnen und Mentoren, die Schülerinnen und Schüler und die Reflexion eigener Unterrichtserfahrungen. Den Faktoren wurden untergeordnete Faktoren (z. B. Hospitationen durch Universitätsdozierende) zugeordnet und es wird dargestellt, warum und unter welchen Umständen diese Lerngelegenheiten für die Entwicklung der Überzeugungen aus Studierendensicht relevant sind.
Das Praxissemester, in dem die Studierenden mehrere Monate am Schulleben teilhaben, ist ein wichtiger Bestandteil schulpraktischer Ausbildung geworden. Die vielfältigen Ziele schließen den Kompetenzerwerb entsprechend den KMK-Vorgaben sowie die Berufswahlüberprüfung ein. Forschungsbefunde deuten jedoch darauf hin, dass nicht alle erhoff ten Ziele in Schulpraktika auch tatsächlich erreicht werden. Die konkreten Lernsituationen im Praxissemester standen hingegen bisher wenig im Fokus. Um dies aufzugreifen, interviewten wir für die vorliegende Studie N = 7 Lehramtsstudierende unmittelbar nach Abschluss ihres Praxissemesters zu den von Ihnen wahrgenommenen Lernerfolgen und den Lerngelegenheiten, in denen sie diese erzielten. Die Ergebnisse zeigen, dass die Studierenden glauben, vor allem ihre Unterrichts-Kompetenzen weiterentwickelt und sich als Lehrkraft sowie ihre Lehrer:innenpersönlichkeit kennengelernt zu haben. Als zentrale Lerngelegenheit benennen sie insbesondere den Austausch mit den Mentorinnen und Mentoren.
Die Fähigkeit zu beraten gilt als ein wichtiger Aspekt professioneller Kompetenz von Lehrkräften. Lehrveranstaltungskonzepte, die theoretisches Beratungswissen vermitteln und gleichzeitig praktische Erfahrungen im Beraten ermöglichen, sind daher hochrelevant für die Entwicklung berufsspezifischer Fähigkeiten. Angelehnt an ein vierdimensionales Modell der Beratungskompetenz wurde an der Universität Potsdam ein Seminarkonzept für angehende Lehrkräfte entwickelt. Es bietet Lerngelegenheiten, um Beratungswissen zu Kommunikations-, Diagnostik-, Problemlöse- und Bewältigungs-Skills zu erwerben und dieses Wissen in konstruierten Beratungssituationen im Seminar anzuwenden, die klassisch für die berufliche Schulpraxis sind. Darüber hinaus wurden die Lehramtsstudierenden motiviert, spezifische Beratungskompetenzen – konkret das aktive Zuhören – im Rahmen der Schulpraktischen Übungen anzuwenden. Erste Erkenntnisse der Analyse der durchgeführten Unterrichtsstunden werden dargestellt.
Im Potsdamer Modell der Lehrerbildung stellt das Praktikum in pädagogisch-psychologischen Handlungsfeldern (PppH) die zweite der fünf vorgesehenen Praxisphasen dar. Die Ziele des PppH sind (1) Sensibilisierung für Heterogenität und Inklusion, (2) Unterstützung bei der Entwicklung einer forschenden Haltung und (3) Förderung von (Selbst-)Reflexion. Konkret wird das außerunterrichtliche Praktikum durch wöchentliche Seminarsitzungen vor- und anschließende Blockveranstaltung nachbereitet. Alle PppH-Veranstaltungen wurden vom WS 15/16 bis WS 17/18 in einer Begleitforschung mit jeweils mehreren Messzeitpunkten eingerahmt. Für die vorliegende Arbeit wurden zwei kontinuierlich korrespondierenden Messzeitpunkte ausgewählt und über vier Semesterkohorten aggregiert. In einem quasi-experimentellen Prä-Post-Design zeigen die empirischen Ergebnisse insgesamt positive Einstellungen und relative hohe Selbstwirksamkeit sowie einige positive Prä-Post-Entwicklungen von kleiner Effektstärke.
Digitale Musikmedien und -technologien in der Musiklehrer*innenausbildung an der Universität Potsdam
(2022)
This chapter takes the ongoing conflict in South Sudan as a starting point for assessing the concept of transitional justice as such and its implementation in the country in particular. Following a brief description of the conflict and the peace processes, the author sheds light on the shortcomings of the established concept of transitional justice in the situation at hand. Then, the author outlines the alternate concept of transformational justice und takes a closer look at its implications on the situation in South Sudan. The author highlights existing initiatives of transformative justice and is very much in favour of their victim-centered approach.
At different times and places, civic engagement in nonviolent resistance (NVR) has repeatedly shown to be an effective tool in times of conflict to initiate societal change from below. History teaches us that there have been successes (Mahatma Gandhi in India) and failures (the Tiananmen Square protests in China).
Along with the recognition of the duality between transformative potential and stark consequences, the historical development of NVR was accompanied by the emergence of scholarly debate, fractured along disputes around purpose, character and effectivity of nonviolent actions taken by civil society stakeholders engaged in making their voices heard. One of the field’s current points of interest is the examination of the long-term effects of NVR movements resulting in societal transformation on the stability and adequacy of a subsequently altered or emerging democracy, suggesting that NVR contributes positively to the sustainable and representative design of an egalitarian governing system.
The conclusion of the Nepalese civil war in 2006 should pose as an unambiguous example for the illustration of this phenomenon, but simultaneously raises the question why there was no successful implementation of a transitional process focusing on the needs of the victims.
Transitional justice is conventionally theorized as how a society deals with past injustices after regime change and alongside democratization. Nonetheless, scholars have not reached a consensus on what is to be included or excluded. Recent ideas of transformative justice seek to expand the understanding of transitional justice to include systemic restructuring and socioeconomic considerations. In the context of Nicaragua — where two transitions occurred within an 11-year span — very little transitional justice took place, in terms of the conventional concept of top-down legalistic mechanisms; however, distinct structural changes and socioeconomic policies can be found with each regime change. By analyzing the transformative justice elements of Nicaragua’s dual transition, this chapter seeks to expand the understanding of transitional justice to include how these factors influence goals of transitions such as sustainable peace and reconciliation for past injustices. The results argue for increased attention to transformative justice theories and a more nuanced conception of justice.
While the concept of transitional justice and its range of measures have gained importance on an international level to come to terms with major crimes of the past, colonial crimes and mass violence committed by Western actors have not been addressed by transitional justice so far. In this chapter, the Herero’s and Nama’s struggle for justice for the genocide on their ancestors by Germany from 1904 – 1908 and the arising challenges are set in relation to conceptual debates in the field of transitional justice. Building on current debates in the field, suggesting more structural and transformative conceptualizations of transitional justice and an approach ‘from below’, it is argued that decolonial activism of formerly colonized communities and transitional justice debates can inform each other in a dialogic and fruitful form to formulate suggestions for a process towards post-colonial justice.
This paper aims to contribute a different approach to transitional justice, one in which political decisions are rocketed to the forefront of the research. Theory asserts that, after a transition to democracy, it is the constituency who defines the direction a country will take. Therefore, pleasing them should be at the fore of the responses taken by those in power. However, reality distances itself from theory. History provides us with many examples of the contrary, which indicates that the politicization of transitional justice is an ever-present event. The first section will outline current definitions and obstacles faced by transitional justice, focusing on the implicit ties between them and the aforementioned politicization. An original categorization of Transitional Justice as a method of analysis will also be introduced, which I denominate Political Opportunism. The case of Argentina, a country that is usually described as a model to export but that after 35 years is still dealing with the consequences brought by the contradictions of using several methods of justice, will then be reinterpreted through this perspective. At the end of the paper, the inevitable question will be posed: can this new angle be exported and implemented in every transition?
This chapter deals with the problem that theories of peace building, conflict resolution and reconciliation were predominately created in the West and, therefore, do not necessarily fit the understanding of peace, conflict, and resolution in non-Western societies and cultures. Within these societies, the acceptance of suffering may also be higher, which leads to different priorities of conflict resolution approaches. Furthermore, this chapter deals with the question of whether the current understanding of wars and the nature of conflict change the basis of established conflict theories. These theoretical approaches are then applied in Sierra Leone as a non-Western negotiation scenario.