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Item Zeitschriftenaufsatz Open Access One Shot inverse scattering revisited(2025) Griesmaier, Roland; Hanke, MartinWe develop and discuss a novel reconstruction algorithm for the inverse source problem and the inverse scattering problem for the Helmholtz equation with well-separated compactly supported sources or scatterers in two-dimensional free space from far field observations of a single radiated or scattered wave. We show that a rational approximation of a Laurent polynomial formed by the low order Fourier coefficients of the given far field pattern can be used to determine straight lines connecting the support of the sources or scatterers to the origin. After repeating this procedure for many different choices of the origin, we apply a filtered backprojection algorithm to recover information on the number and the location of the unknown sources or scatterers. We give numerical examples to illustrate the performance and limitations of our reconstruction algorithm.Item Zeitschriftenaufsatz Open Access Fachkräftemangel in pädagogischen Handlungsfeldern(2024) Betz, Tanja; Idel, Till-Sebastian; Steffensky , MirjamItem Zeitschriftenaufsatz Open Access Neoadjuvante Therapie des lokal fortgeschrittenen Plattenepithelkarzinoms des Ösophagus(2024) Drabke, Sophia; Kaufmann , Justus; Schmidberger , HeinzDie neoadjuvante Radiochemotherapie ist seit über einem Jahrzehnt Standard in der Therapie des lokal fortgeschrittenen Plattenepithelkarzinoms des Ösophagus, welches weiterhin eine schlechte Prognose aufweist. In dieser Studie wurde das Überleben nach neoadjuvanter Radiochemotherapie vs. alleiniger neoadjuvanter Chemotherapie als Dublette vs. Triplette untersucht.Item Zeitschriftenaufsatz Open Access Item Zeitschriftenaufsatz Open Access Kriminologischer Beitrag : Gesinnung und Strafrecht(2024) Weinand, Marisa; Horten, Barbara; Steffan, ChristianItem Zeitschriftenaufsatz Open Access Categories as learning practice : navigating contested belonging along transatlantic mobile trajectories(2025) Drotbohm, HeikeAlthough mobility-related categorization processes are central to migration studies, the ways that mobile populations understand, adapt, or contest them remain understudied. To trace such interpretations across both space and time, this paper explores a migrant trajectory that first crossed national borders within Africa before continuing to Brazil and later proceeding to Canada. The research combines ethnographic insights with the autobiographic reflections of one protagonist, whose perspectives and experiences move between different places, countries, institutions, people, and critical events. Following that individual’s learning processes, this article traces which categories were meaningful in the context of origin, how these changed in the interaction with different authorities, how transformative events played into valorizations, and which signs of categorical dissolution were recognizable during these trajectories. A biographical learning perspective sees not only the aspirations and the ideals but also the pragmatism and skepticism around the impact of mobility-related categories change along such journeys.Item Zeitschriftenaufsatz Open Access How boundary interactions dominate emergent driving of inertial passive probes in active matter(2024) Shea, Jeanine; Jung, Gerhard; Schmid, FriederikeColloidal probes immersed in an active bath have been found to behave like active particles themselves. Here, we use simulations to investigate the mechanisms behind this behavior. We find that the active motion of the colloid cannot be simply attributed to the convective motion in the bath. Instead, the boundary of the probe contributes significantly to these adopted dynamics by causing active bath particles to spontaneously accumulate at the probe. This gathering of active bath particles then pushes the probe, thus promoting its emergent active-particle-like behavior. Furthermore, we find that the dynamic properties of the probe depend on its size in a non-monotonic way, which further highlights the non-trivial interplay between probe and bath.Item Zeitschriftenaufsatz Open Access Verhaltenstherapeutische Diagnostik und Therapie bei Kopfschmerzerkrankungen(2024) Klan, Timo; Diezemann-Prößdorf, Anke; Guth, Anna-Lena; Liesering-Latta, Eva; Dresler, ThomasKopfschmerzerkrankungen (die auch die Gesichtsschmerzen umfassen) sind vielfältig und häufig. Es besteht eine hohe Krankheitslast, dennoch sind Kopfschmerzerkrankungen unterdiagnostiziert und unterversorgt. Kopfschmerzen sollten vor dem Hintergrund des biopsychosozialen Modells gesehen werden. Für die psychologische Diagnostik existieren spezifische Fragebogen, die eine gezielte Behandlungsplanung und -evaluation ermöglichen. Zur psychologischen Behandlung stehen sowohl transdiagnostische als auch kopfschmerzspezifische Interventionen zur Verfügung; diese sollten auf die jeweilige Kopfschmerzerkrankung abgestimmt werden. Psychologische Interventionen können sowohl die Kopfschmerzaktivität als auch die kopfschmerzassoziierte Beeinträchtigung und psychische Belastung reduzieren. Es besteht ein großer Forschungsbedarf zur Optimierung und zur Evaluation psychologisch-psychotherapeutischer Interventionen. AbstractItem Zeitschriftenaufsatz Open Access The role of magnetic dipolar interactions in skyrmion lattices(2025) Jefremovas, Elizabeth M.; Leutner, Kilian; Fischer, Miriam G.; Marqués-Marchán, Jorge; Winkler, Thomas B.; Asenjo, Agustina; Sinova, Jairo; Frömter, Robert; Kläui, MathiasMagnetic skyrmions are topological two-dimensional (2D) spin textures that can be stabilized at room temperature and low magnetic fields in magnetic multilayer stacks. Besides their envisioned applications in data storage and processing, these 2D quasiparticles constitute an ideal model system to study 2D particle properties. More precisely, the role of inter-particle dipolar interactions in 2D ensembles can be fully captured in skyrmion lattices. We engineer a multilayer stack hosting skyrmion lattices and increase the relevance of the dipolar coupling by increasing the number of repetitions n from 𝑛=1 to 𝑛=30. To ascertain the impact on the spin structure, we carry out a series of imaging experiments and find a drastic change of the skyrmion size. We develop an analytical description for the skyrmion radius in the whole multilayer regime, from thin to thick film limits, identifying the key impact of the nucleation process leading to the skyrmion lattice. Our work provides a detailed understanding of the skyrmion-skyrmion interaction, clarifying the role of dipolar interactions as the multilayer stack is expanded in the z direction.Item Zeitschriftenaufsatz Open Access Herbivory can increase plant fitness via reduced interspecific competition—evidence from models and mesocosms(2024) Böttner, Laura; Dudenhausen, Fabio; Nouere, Sara; Malacrinò, Antonino; Schäfer, Martin; Koene, Joris M.; Huber, Meret; Xu, ShuqingHerbivores are generally considered to reduce plant fitness. However, as in natural communities they often feed on several competing plant species, herbivores can also increase plant fitness by reducing interspecific competition among plants. In this study, we developed a testable model to predict plant fitness in the presence of an interspecific competitor and a herbivore that feeds on both plant species. Our model allows prediction of the herbivore and competitor densities at which the focal species will benefit from herbivory. This can be estimated by quantifying the effects of the herbivore on the fitness of the focal plant and on its competitor, and by estimating the levels of intra- and interspecific competition in a pairwise fashion, respectively. We subsequently validated the model in indoor microcosms using three interacting species: an aquatic macrophyte (the giant duckweed Spirodela polyrhiza), its native competitors (green algae) and its native herbivore (the pond snail Lymnaea stagnalis). Additional outdoor mesocosm experiments supported our model under natural conditions. Together, this study provides a conceptual framework to understand how herbivores shape plant fitness in a community context.Item Zeitschriftenaufsatz Open Access Glycidyl ethers from acyclic terpenes : a versatile toolbox for multifunctional poly(ethylene glycol)s with modification opportunities(2024) Schüttner, Sandra; Linden, Gregor M.; Hoffmann, Elena C.; Holzmüller, Philipp; Frey, HolgerMultifunctional poly(ethylene glycol) copolymers (mfPEGs) are accessible via the anionic copolymerization of functional epoxides with ethylene oxide (EO). Glycidyl ethers are conveniently synthesized from bio-renewable alcohols and epichlorohydrin (ECH). Herein, we present the synthesis of a series of acyclic terpenyl glycidyl ethers (TGEs) and their subsequent copolymerization with ethylene oxide (EO) via anionic ring-opening polymerization (AROP). The resulting library of copolymers with varied side chain length and comonomer composition comprises molar masses in the range of 4800 to 8300 g mol−1 and narrow molar mass distributions (Đ = 1.06–1.13). For the copolymerization of the TGEs with EO, detailed 1H NMR in situ kinetic studies revealed a change from ideally random to slight gradient copolyether microstructures with increasing chain length and hydrophobicity of the respective TGE. The living nature of AROP provides control of molar masses, and optimized reaction conditions, such as low reaction temperatures and a weakly bound cesium counterion, suppress the well-known proton abstraction of monosubstituted epoxides. Since the incorporation of the terpenyl side chains impedes crystallization, thermal properties of the copolyethers can be tailored by the monomer feed ratio. Subsequently, hydrogenation and thiol–ene click reactions at the side chain double bonds were carried out as post-polymerization modifications. The application of potassium azodicarboxylate (PADA) in the diimide reduction of the polymers was demonstrated to possess vast potential for the full hydrogenation of the novel copolymers, offering facile purification options. Overall, the copolymerization of EO and TGEs gives access to biobased, tailormade polyethers with various options for post-functionalization.Item Zeitschriftenaufsatz Open Access Recurrent late-onset neutropenia following treatment with different B cell-depleting strategies in multiple sclerosis(2024) Protopapa, Maria; Schraad, Muriel; Pape, Katrin; Steffen, Falk; Steenken, Livia; Zipp, Frauke; Fleischer, Vinzenz; Bittner , StefanBackground: As B cell-depleting therapies in multiple sclerosis (MS) have gained significant importance in the last several years, their long-term safety profile is of considerable clinical interest. Late-onset neutropenia (LON) is a rare, but potentially severe, adverse event that was first described in patients with rheumatic disorders under therapy with rituximab. Ofatumumab was approved in 2021 for the treatment of relapsing-remitting multiple sclerosis (RRMS). Neutropenia occurred in 0.2% of patients in clinical phase 3 trials, and to date, no cases of LON have been reported under ofatumumab treatment. Methods: Here, we report a case of repetitive symptomatic LON under ocrelizumab as well as ofatumumab treatment. Additionally, we review the literature on rare occurrences of LON in patients with MS, neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) undergoing B cell-depleting therapies, including rituximab, ocrelizumab, ofatumumab, inebilizumab, and ublituximab. Findings: In our case, the patient presented with repetitive symptomatic LON under ocrelizumab as well as ofatumumab treatment leading to febrile infections, subsequent use of antibiotics, and application of granulocyte-colony-stimulating factor. After repetitive episodes of LON under both B cell-depleting strategies, cladribine was subsequently initiated. A nine-month follow-up showed a normal neutrophil count and no evidence of disease activity. Conclusions: This case highlights the significance of symptomatic late-onset blood count changes under both ocrelizumab and ofatumumab and emphasizes the importance of continuous monitoring of the differential blood count under B cell-depleting treatment. Funding: This study was supported by the Deutsche Forschungsgemeinschaft (DFG; SFB CRC-TR-128 to F.Z., V.F., and S.B..; SFB 1080 and SFB CRC-1292 to F.Z..; and SFB/TRR 355 to S.B.) and the Hermann and Lilly Schilling Foundation (to S.B.).Item Zeitschriftenaufsatz Open Access Green diatom mutants reveal an intricate biosynthetic pathway of fucoxanthin(2022) Bai, Yu; Cao, Tianjun; Dautermann, Oliver; Buschbeck, Paul; Cantrell, Michael B.; Chen, Yinjuan; Lein, Christopher D.; Shi, Xiaohuo; Ware, Maxwell A.; Yang, Fenghua; Zhang, Huan; Zhang, Lihan; Peers, Graham; Li, Xiaobo; Lohr, MartinFucoxanthin is a major light-harvesting pigment in ecologically important algae such as diatoms, haptophytes, and brown algae (Phaeophyceae). Therefore, it is a major driver of global primary productivity. Species of these algal groups are brown colored because the high amounts of fucoxanthin bound to the proteins of their photosynthetic machineries enable efficient absorption of green light. While the structure of these fucoxanthin-chlorophyll proteins has recently been resolved, the biosynthetic pathway of fucoxanthin is still unknown. Here, we identified two enzymes central to this pathway by generating corresponding knockout mutants of the diatom Phaeodactylum tricornutum that are green due to the lack of fucoxanthin. Complementation of the mutants with the native genes or orthologs from haptophytes restored fucoxanthin biosynthesis. We propose a complete biosynthetic path to fucoxanthin in diatoms and haptophytes based on the carotenoid intermediates identified in the mutants and in vitro biochemical assays. It is substantially more complex than anticipated and reveals diadinoxanthin metabolism as the central regulatory hub connecting the photoprotective xanthophyll cycle and the formation of fucoxanthin. Moreover, our data show that the pathway evolved by repeated duplication and neofunctionalization of genes for the xanthophyll cycle enzymes violaxanthin de-epoxidase and zeaxanthin epoxidase. Brown algae lack diadinoxanthin and the genes described here and instead use an alternative pathway predicted to involve fewer enzymes. Our work represents a major step forward in elucidating the biosynthesis of fucoxanthin and understanding the evolution, biogenesis, and regulation of the photosynthetic machinery in algae.Item Zeitschriftenaufsatz Open Access Edgar’s cliff : the view from a height in King Lear(2024) Irving, Roslyn JoyItem Zeitschriftenaufsatz Open Access Claudins in vulvar cancer : from epithelial barrier to potential tumor-agnostic cancer therapy(2024) Klamminger, Gilbert Georg; Bitterlich, Annick; Nigdelis, Meletios P.; Ertz, Martin; Yoo-Jin, Kim; Hasenburg, Annette; Wagner, MathiasThe immunohistochemical expression of various members of the claudin family has already been studied in pathological affections of the vulva whether to differentiate precancerous lesions from vulvar squamous cell carcinoma or in inflammatory conditions such as lichen sclerosus. From an oncological perspective, however, immunohistochemical analysis of claudin 18.2 protein expression has become increasingly clinically relevant nowadays since the impressive therapeutic benefits of the claudin 18.2 antibody zolbetuximab have been widely recognized. Systematic studies evaluating its expression, including in vulvar cancer, are needed to understand whether such treatment strategies may eventually benefit patients with vulvar neoplasia.Item Zeitschriftenaufsatz Open Access Mapping audience analytics use in newsrooms a conceptual typology integrating individual and organizational influences(2024) Riemann, RobinDespite the pivotal role of audience analytics in journalism, frequency and intensity of their use vary. This paper utilises the Theory of Planned Behavior and journalistic role orientations to consider various influences on audience analytics use, taking into account their complex interplay. Drawing from a comprehensive literature review, individual and organisational influences are identified to inform a conceptual typology of audience analytics users in newsrooms. It distinguishes six types, encompassing Analytics Experts, Integrators, Enthusiasts, Followers, Opportunists and Skeptics. Each type is characterised by specific traits, offering a nuanced understanding of their relationships and positions within newsrooms. This paper offers a refined perspective on how journalism navigates technological changes and economic challenges, and informs media management strategies by providing a deeper understanding of analytics-related newsroom dynamics.Item Zeitschriftenaufsatz Open Access Prospective and retrospective metacognitive judgments of prospective memory performance across the lifespan(2024) Stelz, Steven; Altgassen, MareikeProspective Memory (PM), the ability to carry out future intentions at a specific time or event, develops in an inverted U-shaped function across the lifespan. Most studies have examined age-related changes in PM with regard to the role of executive functions. Although more recent studies have emphasized the importance of metacognition for successful prospective remembering, very little is known about the development of metacognitive abilities across the lifespan and their impact on PM performance. Therefore, the current study examined developmental differences in metacognitive monitoring and PM in five age groups in Germany (N = 151): children (9–10 years), adolescents (14–15 years), young adults (20–25 years), middle-aged adults (30–50 years) and old adults (60+ years). Metacognitive monitoring was assessed by asking participants to judge their performance before (prediction) and after (postdiction) working on a lab-based PM task (Virtual Week). PM performance increased from childhood into adolescence, remaItem Zeitschriftenaufsatz Open Access Excluded voices in inclusive child and youth welfare services(2024) Klein, Alexandra; Langer, Stephanie; Kaddour-Dugonjic, AminaThe voices of social work service users in Germany are getting increasingly prominent. The recent developments in the Child and Youth Welfare Act (SGB VIII) illustrate that participation, self-organisation, and self-representation rights are receiving heightened attention. Simultaneously, questions regarding the requirements, conditions, and possibilities of self-organisation have received relatively minuscule attention so far. Who has the means and opportunities for self-organisation under which conditions? How are social closure processes of significance? What consequences does it have for service users? What insights can we gain at the intersection of social work and special education? In this article, we seek to explore these questions. Initially, we take a journey through history, shedding light on the question of the virulence of social closure and usurpation processes within user movements. Based on this historical recapitulatory overview and repositories of paradigms and theories on social inequaliItem Zeitschriftenaufsatz Open Access The audience is all in (or not) : perceptions of the affordances of journalistic 360° video(2024) Kunert, JessicaThis study shows how the affordances of journalistic 360° video shape and interact with audience perceptions. 360° video is a form of immersive journalism that allows news to be experienced from a first-person perspective while surrounded by a digital space, with the goal of achieving immersion. It is asked how low-level affordances (i.e., storytelling elements of immersive journalism) are perceived and connected to imagined affordances of 360° video, as well as high-level affordances (i.e., communicative outcomes). In-depth interviews were conducted with 37 German news consumers between the ages of 23 and 80, who were shown two videos on different topics and with two headsets of different sophistication. The study found that the low-level affordances of navigating the self in the story (use of a virtual body, direct address) were often perceived as confusing. Moreover, the use of the spatial narrative (use of the 360° space, unusual perspectives) clashed with interviewees' ideas of how journalism should be pItem Zeitschriftenaufsatz Open Access