@phdthesis{Kruse2023,
  author    = {Kruse, Marlen},
  title     = {Characterization of biomolecules and their interactions using electrically controllable DNA nanolevers},
  doi       = {10.25932/publishup-57738},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-577384},
  school      = {Universit{\"a}t Potsdam},
  pages     = {100, xxii},
  year      = {2023},
  abstract  = {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.},
  language  = {en}
}
@phdthesis{Drobyshev2023,
  author    = {Drobyshev, Evgenii},
  title     = {Toxic or beneficial? What is the role of food-relevant selenium species selenoneine?},
  doi       = {10.25932/publishup-57379},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-573794},
  school      = {Universit{\"a}t Potsdam},
  pages     = {xiv, 100},
  year      = {2023},
  abstract  = {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.},
  language  = {en}
}
@misc{Paetzel2023,
  type      = {Master Thesis},
  author    = {P{\"a}tzel, Jonas},
  title     = {Seismic site characterization using broadband and DAS ambient vibration measurements on Mt Etna, Italy},
  doi       = {10.25932/publishup-61379},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-613793},
  school      = {Universit{\"a}t Potsdam},
  pages     = {95},
  year      = {2023},
  abstract  = {Both horizontal-to-vertical (H/V) spectral ratios and the spatial autocorrelation method (SPAC) have proven to be valuable tools to gain insight into local site effects by ambient noise measurements. Here, the two methods are employed to assess the subsurface velocity structure at the Piano delle Concazze area on Mt Etna. Volcanic tremor records from an array of 26 broadband seismometers is processed and a strong variability of H/V ratios during periods of increased volcanic activity is found. From the spatial distribution of H/V peak frequencies, a geologic structure in the north-east of Piano delle Concazze is imaged which is interpreted as the Ellittico caldera rim. The method is extended to include both velocity data from the broadband stations and distributed acoustic sensing data from a co-located 1.5 km long fibre optic cable. High maximum amplitude values of the resulting ratios along the trajectory of the cable coincide with known faults. The outcome also indicates previously unmapped parts of a fault. The geologic interpretation is in good agreement with inversion results from magnetic survey data. Using the neighborhood algorithm, spatial autocorrelation curves obtained from the modified SPAC are inverted alone and jointly with the H/V peak frequencies for 1D shear wave velocity profiles. The obtained models are largely consistent with published models and were able to validate the results from the fibre optic cable.},
  language  = {en}
}
@phdthesis{Stanke2023,
  author    = {Stanke, Sandra},
  title     = {AC electrokinetic immobilization of influenza viruses and antibodies on nanoelectrode arrays for on-chip immunoassays},
  doi       = {10.25932/publishup-61716},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-617165},
  school      = {Universit{\"a}t Potsdam},
  pages     = {x, 115},
  year      = {2023},
  abstract  = {In the present thesis, AC electrokinetic forces, like dielectrophoresis and AC electroosmosis, were demonstrated as a simple and fast method to functionalize the surface of nanoelectrodes with submicrometer sized biological objects. These nanoelectrodes have a cylindrical shape with a diameter of 500 nm arranged in an array of 6256 electrodes. Due to its medical relevance influenza virus as well as anti-influenza antibodies were chosen as a model organism. Common methods to bring antibodies or proteins to biosensor surfaces are complex and time-consuming. In the present work, it was demonstrated that by applying AC electric fields influenza viruses and antibodies can be immobilized onto the nanoelectrodes within seconds without any prior chemical modification of neither the surface nor the immobilized biological object. The distribution of these immobilized objects is not uniform over the entire array, it exhibits a decreasing gradient from the outer row to the inner ones. Different causes for this gradient have been discussed, such as the vortex-shaped fluid motion above the nanoelectrodes generated by, among others, electrothermal fluid flow. It was demonstrated that parts of the accumulated material are permanently immobilized to the electrodes. This is a unique characteristic of the presented system since in the literature the AC electrokinetic immobilization is almost entirely presented as a method just for temporary immobilization. The spatial distribution of the immobilized viral material or the anti-influenza antibodies at the electrodes was observed by either the combination of fluorescence microscopy and deconvolution or by super-resolution microscopy (STED). On-chip immunoassays were performed to examine the suitability of the functionalized electrodes as a potential affinity-based biosensor. Two approaches were pursued: A) the influenza virus as the bio-receptor or B) the influenza virus as the analyte. Different sources of error were eliminated by ELISA and passivation experiments. Hence, the activity of the immobilized object was inspected by incubation with the analyte. This resulted in the successful detection of anti-influenza antibodies by the immobilized viral material. On the other hand, a detection of influenza virus particles by the immobilized anti-influenza antibodies was not possible. The latter might be due to lost activity or wrong orientation of the antibodies. Thus, further examinations on the activity of by AC electric fields immobilized antibodies should follow. When combined with microfluidics and an electrical read-out system, the functionalized chips possess the potential to serve as a rapid, portable, and cost-effective point-of-care (POC) device. This device can be utilized as a basis for diverse applications in diagnosing and treating influenza, as well as various other pathogens.},
  language  = {en}
}
@article{CohenHattab2023,
  author    = {Cohen-Hattab, Kobi},
  title     = {Pioneers of Independent Jewish Shipping},
  series = {PaRDeS : Journal of the Association for Jewish Studies in Germany},
  journal   = {PaRDeS : Journal of the Association for Jewish Studies in Germany},
  number    = {28},
  publisher = {Universit{\"a}tsverlag Potsdam},
  address   = {Potsdam},
  isbn      = {978-3-86956-552-1},
  issn      = {1614-6492},
  doi       = {10.25932/publishup-58554},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-585542},
  pages     = {34 -- 50},
  year      = {2023},
  abstract  = {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.},
  language  = {en}
}
@article{Weinmann2023,
  author    = {Weinmann, Franziska},
  title     = {Mothers of Seafaring},
  series = {PaRDeS : Journal of the Association for Jewish Studies in Germany},
  journal   = {PaRDeS : Journal of the Association for Jewish Studies in Germany},
  number    = {28},
  publisher = {Universit{\"a}tsverlag Potsdam},
  address   = {Potsdam},
  isbn      = {978-3-86956-552-1},
  issn      = {1614-6492},
  doi       = {10.25932/publishup-58556},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-585563},
  pages     = {52 -- 67},
  year      = {2023},
  abstract  = {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.},
  language  = {en}
}
@masterthesis{Eggers2023,
  type      = {Bachelor Thesis},
  author    = {Eggers, Nele},
  title     = {Properties of Arctic aerosol in the transition between Arctic haze to summer season derived by lidar},
  doi       = {10.25932/publishup-61943},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-619438},
  school      = {Universit{\"a}t Potsdam},
  pages     = {x, 63},
  year      = {2023},
  abstract  = {During the Arctic haze period, the Arctic troposphere consists of larger, yet fewer, aerosol particles than during the summer (Tunved et al., 2013; Quinn et al., 2007). Interannual variability (Graßl and Ritter, 2019; Rinke et al., 2004), as well as unknown origins (Stock et al., 2014) and properties of aerosol complicate modeling these annual aerosol cycles. This thesis investigates the modification of the microphysical properties of Arctic aerosols in the transition from Arctic haze to the summer season. Therefore, lidar measurements of Ny-{\AA}lesund from April 2021 to the end of July 2021 are evaluated based on the aerosols' optical properties. An overview of those properties will be provided. Furthermore, parallel radiosonde data is considered for indication of hygroscopic growth. The annual aerosol cycle in 2021 differs from expectations based on previous studies from Tunved et al. (2013) and Quinn et al. (2007). Developments of backscatter, extinction, aerosol depolarisation, lidar ratio and color ratio show a return of the Arctic haze in May. The haze had already reduced in April, but regrew afterwards. The average Arctic aerosol displays hygroscopic behaviour, meaning growth due to water uptake. To determine such a behaviour is generally laborious because various meteorological circumstances need to be considered. Two case studies provide further information on these possible events. In particular, a day with a rare ice cloud and with highly variable water cloud layers is observed.},
  language  = {en}
}
@phdthesis{Pons2023,
  author    = {Pons, Micha{\"e}l},
  title     = {The Nature of the tectonic shortening in Central Andes},
  doi       = {10.25932/publishup-60089},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-600892},
  school      = {Universit{\"a}t Potsdam},
  pages     = {160},
  year      = {2023},
  abstract  = {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.},
  language  = {en}
}
@phdthesis{Gruner2023,
  author    = {Gruner, David},
  title     = {New frontiers in gyrochronology},
  doi       = {10.25932/publishup-61526},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-615268},
  school      = {Universit{\"a}t Potsdam},
  pages     = {x, 131},
  year      = {2023},
  abstract  = {Late-type stars are by far the most frequent stars in the universe and of fundamental interest to various fields of astronomy - most notably to Galactic archaeology and exoplanet research. However, such stars barely change during their main sequence lifetime; their temperature, luminosity, or chemical composition evolve only very slowly over the course of billions of years. As such, it is difficult to obtain the age of such a star, especially when it is isolated and no other indications (like cluster association) can be used. Gyrochronology offers a way to overcome this problem. Stars, just like all other objects in the universe, rotate and the rate at which stars rotate impacts many aspects of their appearance and evolution. Gyrochronology leverages the observed rotation rate of a late-type main sequence star and its systematic evolution to estimate their ages. Unlike the above-mentioned parameters, the rotation rate of a main sequence star changes drastically throughout its main sequence lifetime; stars spin down. The youngest stars rotate every few hours, whereas much older stars rotate only about once a month, or - in the case of some late M-stars - once in a hundred days. Given that this spindown is systematic (with an additional mass dependence), it gave rise to the idea of using the observed rotation rate of a star (and its mass or a suitable proxy thereof) to estimate a star's age. This has been explored widely in young stellar open clusters but remains essentially unconstrained for stars older than the sun, and K and M stars older than 1 Gyr. This thesis focuses on the continued exploration of the spindown behavior to assess, whether gyrochronology remains applicable for stars of old ages, whether it is universal for late-type main sequence stars (including field stars), and to provide calibration mileposts for spindown models. To accomplish this, I have analyzed data from Kepler space telescope for the open clusters Ruprecht 147 (2.7 Gyr old) and M 67 (4 Gyr). Time series photometry data (light curves) were obtained for both clusters during Kepler's K2 mission. However, due to technical limitations and telescope malfunctions, extracting usable data from the K2 mission to identify (especially long) rotation periods requires extensive data preparation. For Ruprecht 147, I have compiled a list of about 300 cluster members from the literature and adopted preprocessed light curves from the Kepler archive where available. They have been cleaned of the gravest of data artifacts but still contained systematics. After correcting them for said artifacts, I was able to identify rotation periods in 31 of them. For M 67 more effort was taken. My work on Ruprecht 147 has shown the limitations imposed by the preselection of Kepler targets. Therefore, I adopted the time series full frame image directly and performed photometry on a much higher spatial resolution to be able to obtain data for as many stars as possible. This also means that I had to deal with the ubiquitous artifacts in Kepler data. For that, I devised a method that correlates the artificial flux variations with the ongoing drift of the telescope pointing in order to remove it. This process was a large success and I was able to create light curves whose quality match and even exceede those that were created by the Kepler mission - all while operating on higher spatial resolution and processing fainter stars. Ultimately, I was able to identify signs of periodic variability in the (created) light curves for 31 and 47 stars in Ruprecht 147 and M 67, respectively. My data connect well to bluer stars of cluster of the same age and extend for the first time to stars redder than early-K and older than 1 Gyr. The cluster data show a clear flattening in the distribution of Ruprecht 147 and even a downturn for M 67, resulting in a somewhat sinusoidal shape. With that, I have shown that the systematic spindown of stars continues at least until 4 Gyr and stars continue to live on a single surface in age-rotation periods-mass space which allows gyrochronology to be used at least up to that age. However, the shape of the spindown - as exemplified by the newly discovered sinusoidal shape of the cluster sequence - deviates strongly from the expectations. I then compiled an extensive sample of rotation data in open clusters - very much including my own work - and used the resulting cluster skeleton (with each cluster forming a rip in color-rotation period-mass space) to investigate if field stars follow the same spindown as cluster stars. For the field stars, I used wide binaries, which - with their shared origin and coevality - are in a sense the smallest possible open clusters. I devised an empirical method to evaluate the consistency between the rotation rates of the wide binary components and found that the vast majority of them are in fact consistent with what is observed in open clusters. This leads me to conclude that gyrochronology - calibrated on open clusters - can be applied to determine the ages of field stars.},
  language  = {en}
}
@phdthesis{Djalali2023,
  author    = {Djalali, Saveh Arman},
  title     = {Multiresponsive complex emulsions: Concepts for the design of active and adaptive liquid colloidal systems},
  doi       = {10.25932/publishup-57520},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-575203},
  school      = {Universit{\"a}t Potsdam},
  pages     = {151},
  year      = {2023},
  abstract  = {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.},
  language  = {en}
}
@phdthesis{Kim2023,
  author    = {Kim, Jiyong},
  title     = {Synthesis of InP quantum dots and their applications},
  doi       = {10.25932/publishup-58535},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-585351},
  school      = {Universit{\"a}t Potsdam},
  pages     = {XIX, 142},
  year      = {2023},
  abstract  = {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.},
  language  = {en}
}
@phdthesis{Lepre2023,
  author    = {Lepre, Enrico},
  title     = {Nitrogen-doped carbonaceous materials for energy and catalysis},
  doi       = {10.25932/publishup-57739},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-577390},
  school      = {Universit{\"a}t Potsdam},
  pages     = {153},
  year      = {2023},
  abstract  = {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.},
  language  = {en}
}
@phdthesis{Stoermann2023,
  author    = {St{\"o}rmann, Florian Konstantin},
  title     = {Multifunctional Microballoons for the active and passive control of fluid-flows},
  school      = {Universit{\"a}t Potsdam},
  pages     = {XVI, 104, A24},
  year      = {2023},
  abstract  = {Functional materials, also called "Smart Materials", are described by their ability to fulfill a desired task through targeted interaction with its environment. Due to this functional integration, such materials are of increased interest, especially in areas where the increasing micronization of components is required. Modern manufacturing processes (e.g. microfluidics) and the availability of a wide variety of functional materials (e.g. shape memory materials) now enable the production of particle-based switching components. This category includes micropumps and microvalves, whose basic function is the active control of liquid flows. One approach in realizing those microcomponents as pursued by this work, enables variable size-switching of water-filled microballoons by implementing a stimulus-sensitive switching motif in the capsule's membrane shell, while being under the influence of a constant driving force. The switching motif with its gatekeeper function has a critical influence on one or more material parameters, which modulate the capsule's resistance against the driving force in microballoon expansion process. The advantage of this concept is that even non-variable analyte conditions, such as concentration levels of ions, can be capitalized to generate external force fields that, under the control of the membrane, cause an inflation of the microballoon by an osmotically driven water influx. In case of osmotic pressure gradients as the driving force for the capsule expansion, material parameters associated with the gatekeeper function are specifically the permeability and the mechanical stiffness of the shell material. While a modulation of the shell permeability could be utilized to kinetically impede the water influx on large time scales, a modulation of the shell's mechanical stiffness even might be utilized to completely prevent the capsule inflation due to a possible non-deformability beneath a certain threshold pressure. In polymer networks, which are a suitable material class for the demanded capsule shell because of their excellent elasticity, both the permeability and the mechanical properties are strongly influenced by the crystallinity of the material. Since the permeability is effectively reduced with increasing crystallinity, while the mechanical stiffness is simultaneously greatly increased, both effects point in the same direction in terms of their functional relationship. For this reason and due to a reversible and contactless modulation of the membrane crystallinity by heat input, crystallites may be suitable switching motifs for controlling the capsule expansion. As second design element of reversible expandable microballoons, the capsule geometry, defined by an aqueous core enveloped by the temperature-sensitive polymer network membrane, should allow an osmotic pressure gradient across the membrane layer. The strength of the inflation pressure and the associated inflation velocity upon membrane melting should be controlled by the salt concentration within the aqueous core, while a turn in the osmotic gradient should furthermore allow the reversible process of capsule deflation. Therefore, it should be possible to build either microvalves and micropumps, while their intended action of either pumping or valving is determined by their state of expansion and the direction of the osmotic pressure gradient.. Microballoons of approximately 300 µm in diameter were formed via droplet-based microfluidics from double-emulsion templates (w/o/w). The elastomeric capsule membrane was formed by photo-crosslinking of methacrylate (MA) functionalized oligo(ε-caprolactone) precursors (≈ 3.8 MA-arms, Mn ≈ 12000 g mol-1) within the organic medium layer (o) via UV-exposure after droplet-formation. After removal of the toluene/chloroform mixture by slow extraction via the continuous aqueous phase, the capsules solidified under the development of a characteristic "mushroom"-like shape at specific experimental conditions (e.g. λ = 308 nm, 57 mJ·s-1·cm-2, 16 min). It could be furthermore shown that in dependency to the process parameters: oligomer concentration and curing-time also spherical capsules were accessible. Long curing-times and high oligomer concentrations at a fixed light-intensity favored the formation of "mushroom"-like capsules, whereas the contrary led to spherical shaped capsules. A comparative study on thin polymer network films of same composition and equal treatment proved a correlation between the film's crosslink density and their contraction capability, while stronger crosslinked polymer networks showed a stronger contraction after solvent removal. In combination with observations during capsule solidification via light-microscopy, where a continuous shaping from almost spherical crosslinked templates to "mushroom"-shaped and solidified capsules was stated, the following mechanism was proposed. In case of low oligomer contents and short curing-times, the contraction of the capsule shell during solvent removal is strongly diminished due to a low degree of crosslinking. Therefore, the solidifying shell could freely collapse onto the aqueous core. In the other case, high oligomer concentrations and long curing-times will favor the formation of highly crosslinked capsule membranes with a strong contraction capability. Due to an observed decentered location of the aqueous core within the swollen polymer network, an uneven radial stress along the capsule's circumference is exerted to the incompressible core. This lead to an uneven contraction during solvent removal and a directed flow of the core fluid into the direction of the minimal stress vector. In consequence, the initially thicker spherical cap contracts, whereas the opposing thinner spherical cap get stretched. The "mushroom"-shape over some advantages over their spherical shaped counterparts, why they were selected for the further experiments. Besides the necessity of a high density of crosslinking for the purpose of extraordinary elasticity and toughness, the form-anisotropy promotes a faster microballoon expandability due to a partial reduction of the membrane thickness. Additionally, pre-stretched regions of thin thickness might provide a better resistance against inflation pressure than spherical but non-stretched capsules of equal membrane thickness. The resulting "mushroom"-shaped microcapsules exhibited a melting point of Tm ≈ 50 - 60 °C and a degree of crystallinity of Xc ≈ 29 - 38 \% depending on the membrane thickness and internal salt content, which is slightly lower than for the non-crosslinked oligomer and reasoned by a limited chain mobility upon crosslinking. Nonetheless, the melting transition of the polymer network was associated with a strong drop in its mechanical stiffness, which was shown to have a strong influence on the osmotic driven expansion of the microcapsules. Capsules that were subjected to osmotic pressures between 1.5 and 4.7 MPa did not expand if the temperature was well below the melting point of the capsule's membrane, i.e. at room temperature. In contrast, a continuous expansion, while approaching asymptotically to a final capsule size, was observed if the temperature exceeded the melting point, i.e. 60 °C. Microballoons, which were kept for 56 days at ∆Π = 1.5 MPa and room temperature, did not change significantly in diameter, why the impact of the mechanical stiffness on the expansion behavior is considered to be the greater than the influence of the shell permeability. The time-resolved expansion behavior of the microballoons above their Tm was subsequently modeled, using difusion equations that were corrected for shape anisotropy and elastic restoring forces. A shape-related and expansion dependent pre-factor was used to dynamically address the influence of the shell thickness differences along the circumference on the inflation velocity, whereas the microballoon's elastic contraction upon inflation was rendered by the inclusion of a hyperelastic constitutive model. An important finding resulting from this model was the pronounced increase in inflation velocity compared to hypothetical capsules with a homogeneous shell thickness, which stresses the benefit of employing shape anisotropic balloon-like capsules in this study. Furthermore, the model was able to predict the finite expandability on basis of entropy-elastic recovery forces and strain-hardening effects. A comparison of six different microballoons with different shell thicknesses and internal salt contents showed the linear relationship between the volumetric expansion, the shell thickness and the applied osmotic pressure, as represented by the model. As the proposed model facilitates the prediction of the expansion kinetics depending on the membranes mechanical and diffusional characteristics, it might be a screening tool for future material selections. In course of the microballoon expansion process, capsules of intermediate diameters could be isolated by recrystallization of the membrane, which is mainly caused by a restoration of the membrane's mechanical stiffness and is otherwise difficult to achieve with other stimuli-sensitive systems. The capsule's crystallinity of intermediate expansion states was nearly unchanged, whereas the lamellar crystal size tends to decreased with the expansion ratio. Therefore, it was assumed that the elastic modulus was only minimally altered and might increased due to the networks segment-chain extension. In addition to the volume increase achieved by inflation, a turn in the osmotic gradient also facilitated the reversible deflation, which was shown in inflation/deflation cycles. These both characteristics of the introduced microballoons are important parameter regarding the realization of micropumps and microvalves. The fixation of expanded microcapsules via recrystallization enabled the storage of entropy-elastic strain-energy, which could be utilized for pumping actions in non-aqueous media. Here, the pumping velocity depended on both, the type of surrounding medium and the applied temperature. Surrounding media that supported the fast transport of pumped liquid showed an accelerated deflation, while high temperatures further accelerate the pumping velocity. Very fast rejection of the incorporated payload was furthermore realized with pierced expanded microballoons, which were subjected to temperatures above their Tm. The possible fixation of intermediate particle sizes provide opportunities for vent constructions that allowed the precise adjustment of specific flow-rates and multiple valve openings and closings. A valve construction was realized by the insertion of a single or multiple microballoons in a microfluidic channel. A complete and a partial closing of the microballoon-valves was demonstrated as a function of the heating period. In this context, a difference between the inflation and deflation velocity was stated, summarizing slower expansion kinetics. Overall, microballoons, which presented both on-demand pumping and reversible valving by a temperature-triggered change in the capsule's volume, might be suitable components that help to design fully integrated LOC devices, due to the implementation of the control switch and controllable inflation/deflation kinetics. In comparison to other state of the art stimuli-sensitive materials, one has to highlight the microballoons capability of stabilizing almost continuously intermediate capsule sizes by simple recrystallization of the microballoon's membrane.},
  language  = {en}
}
@article{Draude2023,
  author    = {Draude, Claude},
  title     = {Working with Diversity in Informatics},
  series = {Hochschuldidaktik Informatik HDI 2021 (Commentarii informaticae didacticae)},
  journal   = {Hochschuldidaktik Informatik HDI 2021 (Commentarii informaticae didacticae)},
  number    = {13},
  publisher = {Universit{\"a}tsverlag Potsdam},
  address   = {Potsdam},
  isbn      = {978-3-86956-548-4},
  issn      = {1868-0844},
  doi       = {10.25932/publishup-61378},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-613787},
  pages     = {13 -- 33},
  year      = {2023},
  abstract  = {Diversity is a term that is broadly used and challenging for informatics research, development and education. Diversity concerns may relate to unequal participation, knowledge and methodology, curricula, institutional planning etc. For a lot of these areas, measures, guidelines and best practices on diversity awareness exist. A systemic, sustainable impact of diversity measures on informatics is still largely missing. In this paper I explore what working with diversity and gender concepts in informatics entails, what the main challenges are and provide thoughts for improvement. The paper includes definitions of diversity and intersectionality, reflections on the disciplinary basis of informatics and practical implications of integrating diversity in informatics research and development. In the final part, two concepts from the social sciences and the humanities, the notion of "third space"/hybridity and the notion of "feminist ethics of care", serve as a lens to foster more sustainable ways of working with diversity in informatics.},
  language  = {en}
}
@article{GrosseBoeltingScheppachMuehling2023,
  author    = {Große-B{\"o}lting, Gregor and Scheppach, Lukas and M{\"u}hling, Andreas},
  title     = {The Place of Ethics in Computer Science Education},
  series = {Hochschuldidaktik Informatik HDI 2021 (Commentarii informaticae didacticae)},
  journal   = {Hochschuldidaktik Informatik HDI 2021 (Commentarii informaticae didacticae)},
  number    = {13},
  publisher = {Universit{\"a}tsverlag Potsdam},
  address   = {Potsdam},
  isbn      = {978-3-86956-548-4},
  issn      = {1868-0844},
  doi       = {10.25932/publishup-61598},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-615982},
  pages     = {173 -- 187},
  year      = {2023},
  abstract  = {Ethical issues surrounding modern computing technologies play an increasingly important role in the public debate. Yet, ethics still either doesn't appear at all or only to a very small extent in computer science degree programs. This paper provides an argument for the value of ethics beyond a pure responsibility perspective and describes the positive value of ethical debate for future computer scientists. It also provides a systematic analysis of the module handbooks of 67 German universities and shows that there is indeed a lack of ethics in computer science education. Finally, we present a principled design of a compulsory course for undergraduate students.},
  language  = {en}
}
@techreport{GraeberHilbertKoenig2023,
  type      = {Working Paper},
  author    = {Graeber, Daniel and Hilbert, Viola and K{\"o}nig, Johannes},
  title     = {Inequality of Opportunity in Wealth},
  series = {CEPA Discussion Papers},
  journal   = {CEPA Discussion Papers},
  number    = {69},
  issn      = {2628-653X},
  doi       = {10.25932/publishup-60967},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-609673},
  pages     = {54},
  year      = {2023},
  abstract  = {While inequality of opportunity (IOp) in earnings is well studied, the literature on IOp in individual net wealth is scarce to non-existent. This is problematic because both theoretical and empirical evidence show that the position in the wealth and income distribution can significantly diverge.We measure ex-ante IOp in net wealth for Germany using data from the Socio-Economic Panel (SOEP). Ex-ante IOp is defined as the contribution of circumstances to the inequality in net wealth before effort is exerted. The SOEP allows for a direct mapping from individual circumstances to individual net wealth and for a detailed decomposition of net wealth inequality into a variety of circumstances; among them childhood background, intergenerational transfers, and regional characteristics. The ratio of inequality of opportunity to total inequality is stable from 2002 to 2019. This is in sharp contrast to labor earnings, where ex-ante IOp is declining over time. Our estimates suggest that about 62\% of the inequality in net wealth is due to circumstances. The most important circumstances are intergenerational transfers, parental occupation, and the region of birth. In contrast, gender and individuals' own education are the most important circumstances for earnings.},
  language  = {en}
}
@techreport{AmorosoHerrmannKritikos2023,
  type      = {Working Paper},
  author    = {Amoroso, Sara and Herrmann, Benedikt and Kritikos, Alexander},
  title     = {The Role of Regulation and Regional Government Quality for High Growth Firms},
  series = {CEPA Discussion Papers},
  journal   = {CEPA Discussion Papers},
  number    = {71},
  issn      = {2628-653X},
  doi       = {10.25932/publishup-61277},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-612771},
  pages     = {32},
  year      = {2023},
  abstract  = {High growth firms (HGFs) are important for job creation and considered to be precursors of economic growth. We investigate how formal institutions, like product- and labor-market regulations, as well as the quality of regional governments that implement these regulations, affect HGF development across European regions. Using data from Eurostat, OECD, WEF, and Gothenburg University, we show that both regulatory stringency and the quality of the regional government influence the regional shares of HGFs. More importantly, we find that the effect of labor- and product-market regulations ultimately depends on the quality of regional governments: in regions with high quality of government, the share of HGFs is neither affected by the level of product market regulation, nor by more or less flexibility in hiring and firing practices. Our findings contribute to the debate on the effects of regulations by showing that regulations are not, per se, "good, bad, and ugly", rather their impact depends on the efficiency of regional governments. Our paper offers important building blocks to develop tailored policy measures that may influence the development of HGFs in a region.},
  language  = {en}
}
@article{Kainz2023,
  author    = {Kainz, Fritz},
  title     = {Extraterritorial Constitutional Rights},
  series = {MenschenRechtsMagazin},
  volume    = {28},
  journal   = {MenschenRechtsMagazin},
  number    = {2},
  publisher = {Universit{\"a}tsverlag Potsdam},
  address   = {Potsdam},
  issn      = {2941-1149},
  doi       = {10.25932/publishup-60996},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-609962},
  pages     = {140 -- 150},
  year      = {2023},
  abstract  = {Im Laufe der vergangenen Jahrzehnte widmeten Lehre und Rechtsprechung der extraterritorialen Anwendbarkeit von Menschenrechtsabkommen erhebliche Aufmerksamkeit. Im Gegensatz fand die extraterritoriale Anwendung verfassungsgesetzlich verankerter Grundrechte nur in den Vereinigten Staaten vergleichbares akademisches Interesse. Insbesondere l{\"a}sst sich ein Mangel an vergleichender Forschung in diesem Bereich feststellen, was zur herrschenden Meinung beitr{\"a}gt, dass internationale Menschenrechtskonventionen den geeigneten Rahmen bieten, unter dem inl{\"a}ndische Gerichte extraterritoriale Fragen des Verfassungsrechts pr{\"u}fen sollten. Dieser Artikel argumentiert, dass inl{\"a}ndische verfassungsrechtliche Regelungen und die zu ihrer Durchsetzung zust{\"a}ndigen Gerichte ein wichtiges Gegengewicht in der festgefahrenen internationalen Extraterritorialit{\"a}tsdebatte spielen sollten. Anhand zweier Fallstudien aus Deutschland und den Vereinigten Staaten wird gezeigt, dass inl{\"a}ndische Verfassungsgerichte manchmal besser geeignet sind als Vertragsorgane, um die Grundwerte der Menschenw{\"u}rde und der Universalit{\"a}t im extraterritorialen Kontext zu wahren. Dies zeigt sich besonders deutlich am Beispiel Deutschlands, das {\"u}ber eine lange Tradition der Integration in internationale Mehrebenensysteme und des grundrechtliche "Bottom-up"-Widerstands innerhalb solcher Systeme verf{\"u}gt. Aktuelle F{\"a}lle des Bundesverfassungsgerichts zur extraterritorialen Anwendung des Grundgesetzes auf ausl{\"a}ndische nachrichtendienstliche Aktivit{\"a}ten und Klimawandel unterst{\"u}tzen diese Theorie. Allerdings kann ein unabh{\"a}ngiger verfassungsrechtlicher Ansatz auch in solchen nationalen Systemen eigenst{\"a}ndige normative Effekte erzielen, welche st{\"a}rker vom internationalen Menschenrechtssystem isoliert sind. So verwendete auch der amerikanische Oberste Gerichtshof (Supreme Court) die inl{\"a}ndische verfassungsrechtliche Doktrin, um die streng territoriale Auslegung des Internationalen Pakts {\"u}ber b{\"u}rgerliche und politische Rechte durch die amerikanische Regierung zu umgehen und einen funktionalen Ansatz f{\"u}r die extraterritoriale Anwendbarkeit von Grundrechten im Fall der Inhaftierung mutmaßlicher Terroristen im Marinest{\"u}tzpunkt von Guant{\´a}namo Bay zu nutzen. Die Untersuchung dieser Beispiele beansprucht nicht, umfassend oder repr{\"a}sentativ die vielf{\"a}ltigen Verfassungen der Welt und ihre Beziehungen zu v{\"o}lkerrechtlichen Menschenrechtsnormen zu untersuchen. Dennoch sollte die unabh{\"a}ngige Wirkung von verfassungsrechtlichen Rahmenbedingungen in diesen beiden disparaten F{\"a}llen umso mehr Anreiz f{\"u}r eine verst{\"a}rkte vergleichende Forschung zu verfassungsrechtlichen Extraterritorialit{\"a}tsregimen und ihrem Beitrag zum Projekt der Menschenrechte bieten.},
  language  = {en}
}
@article{KlempinRehfeldt2023,
  author    = {Klempin, Christiane and Rehfeldt, Daniel},
  title     = {How to Promote and Measure Reflective Skills in Depth and Breadth of English and Physics Teacher Trainees},
  series = {Reflexion in der Lehrkr{\"a}ftebildung: Empirisch - Phasen{\"u}bergreifend - Interdisziplin{\"a}r (Potsdamer Beitr{\"a}ge zur Lehrerbildung und Bildungsforschung ; 4)},
  journal   = {Reflexion in der Lehrkr{\"a}ftebildung: Empirisch - Phasen{\"u}bergreifend - Interdisziplin{\"a}r (Potsdamer Beitr{\"a}ge zur Lehrerbildung und Bildungsforschung ; 4)},
  number    = {4},
  publisher = {Universit{\"a}tsverlag Potsdam},
  address   = {Potsdam},
  isbn      = {978-3-86956-566-8},
  issn      = {2626-3556},
  doi       = {10.25932/publishup-61938},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-619381},
  pages     = {115 -- 121},
  year      = {2023},
  abstract  = {Supporting reflection in preservice during university-based training is, without doubt, a crucial aspect in attaining teacher professionalism. Therefore, an on-campus seminar designed to relate theory to practice and vice versa - the so-called 'Lehr-Lern-Labor-Seminar (LLLS)' - was implemented over the course of five terms to stimulate reflective skills of English and Physics teacher trainees. Investigations on the effectiveness of three types of the LLLS (no video and two types of video-supported reflections) compared to a parallel group (PG) and a control group (CG) occurred in a mixed methods quasi-experimental study. Reflective skills were elicited with vignettes, relevant covariates with questionnaires. Reflective development was then traced in the dimensions depth and breadth employing a qualitative content analysis. MANCOVA (Multivariate Analysis of Covariance) and regression analyses revealed a substantive increase of reflective depth for English and Physics teacher trainees and breadth development for English LLLS-participants in contrast to both, a PG and a CG, even when controlling for the subjects' individual prerequisites.},
  language  = {en}
}
@techreport{KalkuhlFranksGruneretal.2023,
  type      = {Working Paper},
  author    = {Kalkuhl, Matthias and Franks, Max and Gruner, Friedemann and Lessmann, Kai and Edenhofer, Ottmar},
  title     = {Pigou's Advice and Sisyphus' Warning},
  series = {CEPA Discussion Papers},
  journal   = {CEPA Discussion Papers},
  number    = {62},
  issn      = {2628-653X},
  doi       = {10.25932/publishup-57588},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-575882},
  pages     = {66},
  year      = {2023},
  abstract  = {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.},
  language  = {en}
}