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Die Batterie der Zukunft:Wirtschaftschemiker Simon Lux: "Wir brauchen eine langfristige europäische Strategie"
No full textUm die deutschland- und europaweite Batterieproduktion in Zukunft konkurrenzfähig zu gestalten und eine nachhaltige, bezahlbare und zukunftsfeste Energiewende zu erreichen, bedarf es einer langfristigen europäischen Strategie, betont Wirtschaftschemiker Prof. Dr. Simon Lux. Und genau daran mangele es. Während beispielsweise die Regierung in China den Energieausbau strategisch über Jahre hinweg plane, "leben wir in Europa in einer Zeit der politischen Unsicherheit", betont der Batterieexperte. In der neuen Folge des "Umdenken"-Podcasts, die anlässlich des Dossiers "Energie für die Zukunft" erscheint, bewertet er die Potenziale der "Schlüsseltechnologie der Zukunft"
Digitale Medien im Mathematikunterricht der Primarstufe 2024:Beiträge zur 7. PrimaMedien-Sommertagung 2024 in Saarbrücken
No full textSeit 2007 tagt regelmäßig die Arbeitsgruppe PriMaMedien im Arbeitskreis Grundschule der Gesellschaft für Didaktik der Mathematik. Die Mitglieder dieser Arbeitsgruppe teilen das Interesse an der Entwicklung, der Konzeption, dem Einsatz, der Analyse und der Beurteilung digitaler Medien für den Mathematikunterricht in der Primarstufe.
Im Rahmen der Sommertagung 2024 der PriMaMedien-Arbeitsgruppe an der Universität des Saarlandes fanden sich 23 Forschende zusammen, um über aktuelle Forschungs- und Entwicklungsarbeiten zum Einsatz digitaler Medien im Mathematikunterricht der Primarstufe sowie im Elementarbereich zu diskutieren. Darüber hinaus wurden auch digital gestützte Lehr-Lernkonzepte in der Lehrkräfteausbildung in den Blick genommen. Gemäß des ‚Primats der Fachdidaktik' erfolgte eine Auseinandersetzung mit Forschungsprojekten und Lehr- und Lernangeboten, die sich an den technischen Gegebenheiten und daraus resultierenden fachdidaktischen Potentialen orientierten.
Im vorliegenden Tagungsband werden Projekte aus der Forschung, der Schulpraxis und der Lehrkräftebildung dargestellt, die im Rahmen der PriMaMedien-Sommertagung 2024 vorgestellt wurden
Estimates for Kähler metrics with prescribed scalar curvature
No full textDiese Arbeit untersucht zwei Aspekte des Verhaltens von Kählermannigfaltigkeiten mit kontrollierter skalaren Krümmung.
Der erste Teil befasst sich mit der Stabilität des Positiven Massentheorems für asymptotisch euklidische (AE) Kählermannigfaltigkeiten mit nichtnegativer skalaren Krümmung. Zunächst beweisen wir eine Integrationsungleichung für die ADM-Masse auf AE-Kählermannigfaltigkeiten beliebiger komplexer Dimension. Mithilfe dieses Ergebnisses beweisen wir einen Stabilitätssatz für jede Folge von AE-Kählermannigfaltigkeiten, deren ADM-Masse gegen null konvergiert.
Der zweite Teil untersucht das Grenzverhalten von Kählermetriken mit gleichmäßig beschränkter skalaren Krümmung am Apex einer konischen Kählermannigfaltigkeit. Zunächst beweisen wir einen Liouville-Satz für Kählermetriken mit konstanter skalaren Krümmung (cscK).
Anschließend entwickeln wir eine Hölder-artige Abschätzung für gleichmäßig beschränkte Kählermetriken auf einer Kugel um den Apex. Diese Abschätzung gilt für kleine positive Exponenten unter der Annahme gleichmäßig beschränkter skalaren Krümmung. Als Korollar dieses Ergebnisses zeigen wir, dass eine solche Kählermetrik asymptotisch zur Ricci-flachen Kegelmetrik mit polynomialer Abklingrate ist.This thesis studies two aspects of the behavior of Kähler manifolds with controlled scalar curvature.
The first part studies the stability of the Positive Mass Theorem for asymptotically Euclidean (AE) Kähler manifolds with nonnegative scalar curvature. We first prove an integral inequality for the ADM mass on AE Kähler manifolds of all complex dimensions. Using this, we prove a stability result for any sequence of AE Kähler manifolds with ADM mass converging to zero.
The second part studies the limiting behavior of Kähler metrics with uniformly bounded scalar curvature and at the apex of a conical Kähler manifold. We first establish a Liouville theorem for constant scalar curvature Kähler (cscK) metrics on.
Next, we develop a Hölder-type estimate for uniformly bounded Kähler metrics on a ball around the apex This estimate applies for small, positive exponents under the assumption of uniformly bounded scalar curvature. As a corollary of this result, we show that such a Kähler metric is asymptotic to the Ricci-flat cone metric with polynomial decay rate
GEFAAR: a generic framework for the analysis of antimicrobial resistance providing statistics and cluster analyses
No full textEasy access to antimicrobial resistance data and meaningful visualization is essential to guide the empirical antimicrobial treatment and to promote the rational use of antimicrobial agents. Currently available solutions are commonly externally hosted, centralized systems. However, there is a need for close monitoring by local analysis tools. To fill this gap, we developed GEFAAR—a generic framework for the analysis of antimicrobial resistance data. Following the example of the German Robert Koch Institute (RKI), an interactive web-application is provided to determine basic pathogen and resistance statistics. In addition to the RKI’s externally maintained database, our application provides a generic framework to import tabular data and to analyze them safely in a local environment. Moreover, our application offers an intuitive web-based user interface to visualize resistance trend analysis as well as advanced cluster analyses on species- or clinic/unit level to generate alerts of potential transmission events
Ideations of social sustainability? Concepts and cleavages of cohesion in Germany
No full textThe UN 2030 Agenda calls for the development and promotion of societies that pursue not only ecological and economic, but also socio-political sustainability goals. Yet, the political as well as academic discourse on that is marginal. Conducting an empirical case study in Germany, this article examines existing political ideations about societal integration and thus cohesion and discusses ideational obstacles to the development of a socially sustainable society. First, the concept of ideations is made accessible for empirical analysis by distinguishing cognitive and affective elements with symbolic, sentimental, programmatical and ideological foundations. The focus is not on the implementation of specific policies, but on the negotiation processes of the ideational foundations of integration governance. The following critical discourse analysis elaborates central aspects of ‘constitutional patriotism' and ‘Leitkultur.' It traces their emergence and characteristics and thereby reveals how different historical contexts and political interests of the actors influence the emergence and dissemination of ideations. Furthermore, it demonstrates how formerly opposing positions converge, emphasizing the impact of ideational processes on changing governance trends. Subsequently, inherent elements of cultural racism and hegemony, religion and ‘values,' and emotion politics are critically discussed as obstacles to developing decolonial ideations about integration. Accordingly, the widespread appreciation of patriotism and national pride as a foundation for successful integration is questioned. The conclusion diagnoses that republican elements are gaining influence with the tendency to individualize, paternalize, and depoliticize integration. Shared cognitive and emotional ideations are intended to ensure support for democracy, but the extent to which these policies themselves exhibit undemocratic tendencies must be critically observed. The two ideations examined are therefore not or only partially suitable for promoting social sustainability
Persistent Monocytic Bioenergetic Impairment and Mitochondrial DNA Damage in PASC Patients with Cardiovascular Complications
No full textCardiovascular complications are a hallmark of Post-Acute Sequelae of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection (PASC), yet the mechanisms driving persistent cardiac dysfunction remain poorly understood. Emerging evidence implicates mitochondrial dysfunction in immune cells as a key contributor. This study investigated whether CD14++ monocytes from long COVID patients exhibit bioenergetic impairment, mitochondrial DNA (mtDNA) damage, and defective oxidative stress adaptation, which may underlie cardiovascular symptoms in PASC. CD14++ monocytes were isolated from 14 long COVID patients with cardiovascular symptoms (e.g., dyspnea, angina) and 10 age-matched controls with similar cardiovascular risk profiles. Mitochondrial function was assessed using a Seahorse Agilent Analyzer under basal conditions and after oxidative stress induction with buthionine sulfoximine (BSO). Mitochondrial membrane potential was measured via Tetramethylrhodamine Ethyl Ester (TMRE) assay, mtDNA integrity via qPCR, and reactive oxygen species (ROS) dynamics via Fluorescence-Activated Cell Sorting (FACS). Parallel experiments exposed healthy monocytes to SARS-CoV-2 spike protein to evaluate direct viral effects. CD14++ monocytes from long COVID patients with cardiovascular symptoms (n = 14) exhibited profound mitochondrial dysfunction compared to age-matched controls (n = 10). Under oxidative stress induced by buthionine sulfoximine (BSO), long COVID monocytes failed to upregulate basal respiration (9.5 vs. 30.4 pmol/min in controls, p = 0.0043), showed a 65% reduction in maximal respiration (p = 0.4035, ns) and demonstrated a 70% loss of spare respiratory capacity (p = 0.4143, ns) with significantly impaired adaptation to BSO challenge (long COVID + BSO: 9.9 vs. control + BSO: 54 pmol/min, p = 0.0091). Proton leak, a protective mechanism against ROS overproduction, was blunted in long COVID monocytes (3-fold vs. 13-fold elevation in controls, p = 0.0294). Paradoxically, long COVID monocytes showed reduced ROS accumulation after BSO treatment (6% decrease vs. 1.2-fold increase in controls, p = 0.0015) and elevated mitochondrial membrane potential (157 vs. 113.7 TMRE fluorescence, p = 0.0179), which remained stable under oxidative stress. mtDNA analysis revealed severe depletion (80% reduction, p < 0.001) and region-specific damage, with 75% and 70% reductions in amplification efficiency for regions C and D (p < 0.05), respectively. In contrast, exposure of healthy monocytes to SARS-CoV-2 spike protein did not recapitulate these defects, with preserved basal respiration, ATP production, and spare respiratory capacity, though coupling efficiency under oxidative stress was reduced (p < 0.05). These findings suggest that mitochondrial dysfunction in long COVID syndrome arises from maladaptive host responses rather than direct viral toxicity, characterized by bioenergetic failure, impaired stress adaptation, and mitochondrial genomic instability. This study identifies persistent mitochondrial dysfunction in long COVID monocytes as a critical driver of cardiovascular complications in PASC. Key defects—bioenergetic failure, impaired stress adaptation and mtDNA damage—correlate with clinical symptoms like heart failure and exercise intolerance. The stable elevation of mitochondrial membrane potential and resistance to ROS induction suggest maladaptive remodeling of mitochondrial physiology. These findings position mitochondrial resilience as a therapeutic target, with potential strategies including antioxidants, mtDNA repair agents or metabolic modulators. The dissociation between spike protein exposure and mitochondrial dysfunction highlights the need to explore host-directed mechanisms in PASC pathophysiology. This work advances our understanding of long COVID cardiovascular sequelae and provides a foundation for biomarker development and targeted interventions to mitigate long-term morbidity
Radiation doses to mediastinal organs at risk in early-stage unfavorable Hodgkin lymphoma– a risk stratified analysis of the GHSG HD17 trial
No full textIntroduction: The German Hodgkin Study Group (GHSG) HD17 trial established the omission of radiotherapy (RT) for patients with early-stage unfavorable Hodgkin lymphoma being PET-negative after 2 cycles of BEACOPP escalated plus 2 cycles of ABVD. This patient group reveals heterogeneity in characteristics and disease extent which prompted us to perform a decisive dosimetric analysis according to GHSG risk factors. This may help to tailor RT individually balancing risks and benefits.
Methods: For quality assurance, RT-plans were requested from the treating facilities (n= 141) and analyzed centrally. Dose-volume histograms were scanned either paper-based or digitally to obtain doses to mediastinal organs. These were registered and compared according to GHSG risk factors.
Results: Overall, RT plans of 176 patients were requested, 139 of which had dosimetric information on target volumes within the mediastinum. Most of these patients were stage II (92.8%), had no B-symptoms (79.1%) and were aged < 50 years (89.9%). Risk factors were present in 8.6% (extranodal involvement), 31.7% (bulky disease), 46.0% (elevated erythrocyte sedimentation rate) and 64.0% (three involved areas), respectively. The presence of bulky disease significantly affected the mean RT doses to the heart (p=0.005) and to the left lung (median: 11.3 Gy vs. 9.9 Gy; p=0.042) as well as V5 of the right and left lung, respectively (median right lung: 67.4% vs. 51.0%; p=0.011; median left lung: 65.9% vs. 54.2%; p=0.008). Significant differences in similar organs at risk parameters could be found between the sub-cohorts with the presence or absence of extranodal involvement, respectively. In contrast, an elevated erythrocyte sedimentation rate did not deteriorate dosimetry significantly. No association of any risk factor with radiation doses to the female breast was found. Conclusion: Pre-chemotherapy risk factors may help to predict potential RT exposure to normal organs and to critically review treatment indication. Individualized risk-benefit evaluations for patients with HL in early-stage unfavorable disease are mandatory
The Nature and Persistence of Posthypnotic Suggestions' Effects on Food Preferences: An Online Study
No full textFood preferences are crucial for diet-related decisions, which substantially impact individual health and global climate. However, the persistence of unfavorable food preferences is a significant obstacle to changing eating behavior. Here we explored the effects of posthypnotic suggestions (PHS) on food-related decisions by measuring food choices, subjective ratings, and indifference points. In Session 1, demographic data and hypnotic susceptibility of participants were assessed. In Session 2, following hypnosis induction, PHS aiming to increase the desirability of healthy food was delivered. Afterward, a task set was administrated twice, once when PHS was activated and once deactivated. The order of PHS activation was counterbalanced across participants. The task set included a liking-rating task for 170 pictures of different food items, followed by an online supermarket where participants were instructed to select enough food for a fictitious week of quarantining from the same item pool. After 1 week, Session 3 repeated Session 2 without hypnosis induction in order to assess the persistence of PHS. The crucial dependent measures were food choices, subjective ratings, and the indifference points as a function of time and PHS condition
The significance of structural rich club hubs for the processing of hierarchical stimuli
No full textThe brain's structural network follows a hierarchy that is described as rich club (RC) organization, with RC hubs forming the well-interconnected top of this hierarchy. In this study, we tested whether RC hubs are involved in the processing of hierarchically higher structures in stimulus sequences. Moreover, we explored the role of previously suggested cortical gradients along anterior-posterior and medial-lateral axes throughout the frontal cortex. To this end, we conducted a functional magnetic resonance imaging (fMRI) experiment and presented participants with blocks of digit sequences that were structured on different hierarchically nested levels. We additionally collected diffusion weighted imaging data of the same subjects to identify RC hubs. This classification then served as the basis for a region of interest analysis of the fMRI data. Moreover, we determined structural network centrality measures in areas that were found as activation clusters in the whole-brain fMRI analysis. Our findings support the previously found anterior and medial shift for processing hierarchically higher structures of stimuli. Additionally, we found that the processing of hierarchically higher structures of the stimulus structure engages RC hubs more than for lower levels. Areas involved in the functional processing of hierarchically higher structures were also more likely to be part of the structural RC and were furthermore more central to the structural network. In summary, our results highlight the potential role of the structural RC organization in shaping the cortical processing hierarchy
A higher index theorem on finite-volume locally symmetric spaces
No full textLet G be a connected, real semisimple Lie group. Let K < G be maximal compact, and let Γ < G be discrete and such that Γ\G has finite volume. If the real rank of G is 1 and Γ is torsion-free, then Barbasch and Moscovici obtained an index theorem for Dirac operators on the locally symmetric space Γ\G/K. We obtain a higher version of this, using an index of Dirac operators on G/K in the K-theory of an algebra on which the conjugation-invariant terms in Barbasch and Moscovici’s index theorem define continuous traces. The resulting index theorems also apply when Γ has torsion. The cases of these index theorems for traces defined by semisimple orbital integrals extend to Song and Tang’s higher
orbital integrals, and yield nonzero and computable results even when rank(G) > rank(K), or the real rank of G is larger than 1