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The two-particle momentum correlation functions between charm mesons (D∗± and D±) and charged light-flavor mesons (π± and K±) in all charge-combinations are measured for the first time by the ALICE Collaboration in high-multiplicity proton–proton collisions at a center-of-mass energy of √s = 13 TeV. For DK and D∗K pairs, the experimental results are in agreement with theoretical predictions of the residual strong interaction based on quantum chromodynamics calculations on the lattice and chiral effective field theory. In the case of Dπ and D∗π pairs, tension between the calculations including strong interactions and the measurement is observed. For all particle pairs, the data can be adequately described by Coulomb interaction only, indicating a shallow interaction between charm and light-flavor mesons. Finally, the scattering lengths governing the residual strong interaction of the Dπ and D∗π systems are determined by fitting the experimental correlation functions with a model that employs a Gaussian potential. The extracted values are small and compatible with zero.
Focusing on the specific case of knowledge production in and about Iran, in this chapter, we discuss the risk of reproducing a Northern perspective in the attempts to produce knowledge on and through the Global South(s). We argue that such reproduction leads to cognitive suppression, further peripheralization, or even recolonization of the South(s). We also stress the lasting effects of methodological nationalism among attempts at decolonization and its political consequences, such as in the adoption of nativist discourses historically connected to the 'Islamic' Revolution by scholars focusing on the Global South(s) and in area studies concerning Iran. To avoid these effects, we suggest considering the politics of scale in our recognition and problematization of the hierarchization of Northern and Southern sites of knowledge production and their particularities.
During fieldwork, anthropologists are given many names that point to their intersectional placement regarding race, class, gender, nationality, and religion. Yet, careful consideration of vernacular forms of designation reveals that such generalizing categories do not always reflect the ways in which people are named and positioned in a given context. While acknowledging the relevance of intersectionality, this paper discusses the relationship between naming and social positionality through a comparative consideration of names employed to designate Dulley in Angola and Santos in Senegal. It explores how these designators, ascribed to the researchers by their interlocutors, contextually identify their positionality. Through concrete examples, it shows how this process of emplacement can both enable and restrict one's possibilities of action and experience.
With reference to the Marx Seminars at the University of São Paulo, this chapter discusses the creation of a specific tradition in the social sciences that marks a crucial moment in the history of postcolonial and decolonial studies. By means of the concept of periphery, I reconstruct how this tradition refuted temporal and stadial dualisms. Moreover, I argue that the development of this new perspective in the social sciences must be understood in terms of its efforts to rethink Marx but also, and more importantly, by the need to rethink Brazil's place in the world. Following this thread, I analyse Roberto Schwarz's work as paradigmatic for a proper understanding of the centrality of the concept of periphery in these discussions.
Der Beitrag sucht Georg Christoph Lichtenbergs Position im Sprachdenken der zweiten Hälfte des 18. Jahrhunderts zu bestimmen. Diese ist durch eine Kombination von anthropologischen und technisch-pragmatischen, sprachhandwerklichen Überlegungen zur "Wörterfertigung" geprägt, bei der Fragen von Lexik und Nomenklatur im Vordergrund stehen. Zu den Leitkriterien des guten Stils gehören Lichtenberg zufolge Wahrheit und Genauigkeit sowie Natürlichkeit und Individualisierung.
Microbial rhodopsins are omnipresent on Earth, however the vast majority of them remain uncharacterized. Here we describe a new rhodopsin group from cold-adapted organisms and cold environments, such as glaciers, denoted as CryoRhodopsins (CryoRs). Our data suggest that CryoRs have dual functionality switching between inward transmembrane proton translocation and photosensory activity, both of which can be modulated with UV light. CryoR1 exhibits two subpopulations in the ground state, which upon light activation lead to transient photocurrents of opposing polarities. A distinguishing feature of the group is the presence of a buried arginine residue close to the cytoplasmic face of its members. Combining single-particle cryo-electron microscopy and X-ray crystallography with the rhodopsin activation by lit, we demonstrate that the arginine stabilizes a UV-absorbing intermediate of an extremely slow CryoRhodopsin photocycle. Together with extensive spectroscopic characterization, our investigations on CryoR1 and CryoR2 proteins reveal mechanisms of photoswitching in the newly identified group and demonstrate principles of the adaptation of these rhodopsins to low temperatures.Microbial rhodopsins are omnipresent on Earth, however the vast majority of them remain uncharacterized. Here we describe a new rhodopsin group from cold-adapted organisms and cold environments, such as glaciers, denoted as CryoRhodopsins (CryoRs). Our data suggest that CryoRs have dual functionality switching between inward transmembrane proton translocation and photosensory activity, both of which can be modulated with UV light. CryoR1 exhibits two subpopulations in the ground state, which upon light activation lead to transient photocurrents of opposing polarities. A distinguishing feature of the group is the presence of a buried arginine residue close to the cytoplasmic face of its members. Combining single-particle cryo-electron microscopy and X-ray crystallography with the rhodopsin activation by light, we demonstrate that the arginine stabilizes a UV-absorbing intermediate of an extremely slow CryoRhodopsin photocycle. Together with extensive spectroscopic characterization, our investigations on CryoR1 and CryoR2 proteins reveal mechanisms of photoswitching in the newly identified group and demonstrate principles of the adaptation of these rhodopsins to low temperatures.
EF-P and its paralog EfpL (YeiP) differentially control translation of proline containing sequences
(2024)
Polyproline sequences (XPPX) stall ribosomes, thus being deleterious for all living organisms. In bacteria, translation elongation factor P (EF-P) plays a crucial role in overcoming such arrests. 12% of eubacteria possess an EF-P paralog – YeiP (EfpL) of unknown function. Here, we functionally and structurally characterize EfpL from Escherichia coli and demonstrate its yet unrecognized role in the translational stress response. Through ribosome profiling, we analyzed the EfpL arrest motif spectrum and discovered additional stalls beyond the canonical XPPX motifs at single-proline sequences (XPX), that both EF-P and EfpL can resolve. Notably, the two factors can also induce pauses. We further report that, contrary to the housekeeping EF-P, EfpL can sense the metabolic state of the cell, via lysine acylation. Together, our work uncovers a new player in ribosome rescue at proline-containing sequences, and provides evidence that co-occurrence of EF-P and EfpL is an evolutionary driver for higher bacterial growth rates.
Coarse-grained modeling has become an important tool to supplement experimental measurements, allowing access to spatio-temporal scales beyond all-atom based approaches. The GōMartini model combines structure- and physics-based coarse-grained approaches, balancing computational efficiency and accurate representation of protein dynamics with the capabilities of studying proteins in different biological environments. This paper introduces an enhanced GōMartini model, which combines a virtual-site implementation of Gō models with Martini 3. The implementation has been extensively tested by the community since the release of the new version of Martini. This work demonstrates the capabilities of the model in diverse case studies, ranging from protein-membrane binding to protein-ligand interactions and AFM force profile calculations. The model is also versatile, as it can address recent inaccuracies reported in the Martini protein model. Lastly, the paper discusses the advantages, limitations, and future perspectives of the Martini 3 protein model and its combination with Gō models.
Highlights
• Students have limited concerns about privacy in learning analytics (LA).
• Students' privacy concerns in LA vary across countries.
• Culture shapes students' privacy concerns in LA.
• Power distance, uncertainty avoidance and masculinity affect privacy concerns in LA.
• Cultural values should be considered in LA privacy management.
Abstract
Applications of learning analytics (LA) can raise concerns from students about their privacy in higher education contexts. Developing effective privacy-enhancing practices requires a systematic understanding of students’ privacy concerns and how they vary across national and cultural dimensions. We conducted a survey study with established instruments to measure privacy concerns and cultural values for university students in five countries (Germany, South Korea, Spain, Sweden, and the United States; N = 762). The results show that students generally trusted institutions with their data and disclosed information as they perceived the risks to be manageable even though they felt somewhat limited in their ability to control their privacy. Across the five countries, German and Swedish students stood out as the most trusting and least concerned, especially compared to US students who reported greater perceived risk and less control. Students in South Korea and Spain responded similarly on all five privacy dimensions (perceived privacy risk, perceived privacy control, privacy concerns, trusting beliefs, and non-self-disclosure behavior), despite their significant cultural differences. Culture measured at the individual level affected the antecedents and outcomes of privacy concerns. Perceived privacy risk and privacy control increase with power distance. Trusting beliefs increase with a desire for uncertainty avoidance and lower masculinity. Non-self-disclosure behaviors rise with power distance and masculinity and decrease with more uncertainty avoidance. Thus, cultural values related to trust in institutions, social equality and risk-taking should be considered when developing privacy-enhancing practices and policies in higher education.
A powerful technique to distinguish the enantiomers of a chiral molecule is the Coulomb Explosion Imaging (CEI). This technique allows us to determine the handedness of a single molecule. In CEI, the molecule becomes charged by losing many electrons in a very short period of time by interacting with the light. The repulsion forces between the positive charged particles of the molecule leads the molecule to break into parts-fragments. By measuring the three vector momentum of (at least) four fragments, the handedness observable can be determined. In this thesis, CEI is induced by absorption of a single high energy photon, which creates an inner-shell hole (K shell) of the molecule. The subsequent cascade of Auger decays lead to fragmentation. We decided to work with the formic acid molecule in this thesis. Two different experiments were conducted. The first experiment focused on exciting electrons to different energy states, while the second experiment focused on extracting directly a photoelectron to the continuum and measure the angular distribution of the photoelectron in the molecular frame. The primary goal was to search for chiral signal in a pure achiral planar molecule under the previous electron processes. The results of these findings were further implemented to two more molecules.
Für die Mitte des 18. Jahrhunderts wurde ein umfassender Wandel im Bereich des Stilverständnisses konstatiert, das ab 1750 von zwei gegensätzlichen Stilbegriffen geprägt ist: einem traditionell rhetorischen einerseits und einem sich neu etablierenden Individualstil andererseits. Der Beitrag versucht, mit einem Schlaglicht auf das Frühwerk Johann Georg Hamanns ("Sokratische Denkwürdigkeiten" und "Wolken") diesen für das Verständnis der stilgeschichtlichen Umbrüche zentralen Autor im skizzierten Diskursfeld zu verorten. Ein näherer Blick auf Hamanns sokratische Schreibart erlaubt es, die geläufige Rollenzuschreibung, die in Hamann vor allem einen Wegbereiter des Individualstils erkennt, zu problematisieren und ein Paradox herauszuarbeiten: Die Entwicklung zum Individualstil beginnt im Falle von Hamanns ironisch verstellter Maskenrede mit einer radikalen Depotenzierung der Autorinstanz.
In seiner "Poétique française" (1763) und seinen "Eléments de littérature" (1787) entwickelt der französische Dichter und Theoretiker Jean-François Marmontel Ansichten zum Stil, die von der traditionellen Regelpoetik geprägt sind, allmählich aber einen Übergang zur Individualstilpoetik andeuten. Während er diese verschiedenen Paradigmen durch den Geschmacksbegriff noch zu vereinen sucht, zeigt die deutsche Rezeption seiner Theorie, insbesondere Gottlob Benedikt von Schirachs Übertragung, wie sich der Kompromiss aufzulösen beginnt und wie sich neben der Durchsetzung der Individualstilpoetik auch eine Trennung zwischen Wissenschaft und Kunst anbahnt.
Beispiel und Regel im 18. Jahrhundert. Ein Blick in Christian Ludwigs zweisprachige Wörterbücher
(2024)
Zweisprachige Wörterbücher des 18. Jahrhunderts sind eine wichtige Quelle für die Analyse impliziter stilistischer Urteile. Sie wurden einerseits, insbesondere in der zweiten Jahrhunderthälfte, von den präskriptiven Regeln der großen monolingualen Wörterbücher und Grammatiken beeinflusst, andererseits hatten sie die Aufgabe, Fremdsprachenlernern deskriptiv Gebrauchsmuster an Beispielen vorzuführen. Der Beitrag zeichnet nach, wie sich die Autoren dieser doppelten Herausforderung stellten und wie das entstehende präskriptive Regelsystem vor dem Hintergrund der Stilpluralisierung im 18. Jahrhundert zu interpretieren ist.
In seinem Frühwerk "Über die neuere deutsche Literatur" arbeitet der junge Johann Gottfried Herder an der Herausbildung einer neuen Prosa. Durch kommentiertes Zitieren aus den "Briefen, die neueste Literatur betreffend" entwirft er das Ideal einer 'biegsamen' und 'behaglichen' ungebundenen Schreibweise, die sich ganz wesentlich in Stilversuchen manifestiert - in beschriebenen, kritisierten und zitierten sowie denjenigen des Verfassers selbst.
Der Begriff des 'körnigen Stils' steht in der Sprach- und Literaturkritik des 18. Jahrhunderts für eine kurze und gehaltvolle, oft auch als 'nachdrücklich' beschriebene Schreibart. Im Literaturstreit zwischen Johann Christoph Gottsched und den 'Schweizern' erlangte er zugleich programmatische und polemische Bedeutung. Im Zentrum des Aufsatzes steht die für das 'Körnige' konstitutive Konstellation von Kürze, Kraft und Konkretion. Ausgehend von Theodor W. Adornos stilsoziologischer Beobachtung, dass der lakonische Stil in Briefen des 18. Jahrhunderts Ausdruck bürgerlicher Notdurft sei, zeige ich an Texten von Johann Christoph Adelung, Johann Jacob Breitinger, Gottfried Wilhelm Leibniz und Johann Gottfried Herder, dass das Stilideal des Körnigen im 18. Jahrhundert mit dem Streben nach einer Erneuerung und Bereicherung der deutschen Schriftsprache einherging. Zum Kapital, aus dem diese neue Sprache sich speisen sollte, gehörte das ausdifferenzierte Vokabular des Handwerks und des Handels. Der zeitgenössischen Theorie zufolge stellte der körnige Stil also weniger die Notdurft als den Reichtum und die Sprachmächtigkeit des Bürgertums zur Schau.
Am Nachdruck, wie er bei Johann Christoph Gottsched, Johann Jacob Bodmer, Johann Jacob Breitinger, Johann Georg Sulzer und Johann Gottfried Herder diskutiert wird, lässt sich exemplarisch beobachten, wie eine Gruppe von rhetorischen Verfahren zur Kennzeichnung von nationalen Kollektivstilen ausgebaut wird. Eine wichtige Voraussetzung für die Ausweitung des Nachdrucks von einer Stilfigur zu einem 'nachdrücklichen Stil', so die hier verfolgte These, ist der über physikalische Leitvorstellungen von Druck, Stoß und Wurf geleistete metaphorische Anschluss an ästhetische Kraftvorstellungen.
Der Beitrag untersucht den Gebrauch des Tonbegriffs im ästhetischen und poetologischen Diskurs des mittleren und späten 18. Jahrhunderts. Ausgangspunkt dafür ist eine Verhältnisbestimmung der Termini Schreibart, Stil und Ton, aus der die gattungspoetologische Bedeutung des Tons hervorgeht. Entgegen dem seit der romantischen Ästhetik dominanten Verständnis verbindet die Dichtungstheorie des 18. Jahrhunderts (Friedrich Gottlieb Klopstock, Johann Joachim Eschenburg, Johann Jakob Engel, Johann Christoph Adelung) mit dem Begriff nicht nur die klangliche Dimension von Literatur, sondern auch eine affektive Grundierung von Gattungsformen und ein Konzept für die Beschreibung von gattungshybriden Texten.
In this brief discussion, I reflect on the significance of using the category of the global south for reconfiguring the scope of the history of knowledge. While I see this as a productive paradigm shift that has already given rise to mould-breaking works, I focus here on the cross-hemispheric histories of extractive capitalism and how both colonial violence and anticolonial resistance have shaped knowledge-making. I argue that thinking through 'entangled ecologies' can be a tool for countering the existing conceptual order, which has led to the north-south division in the first place. Attending to epistemic and ontological entanglements would enable us to ask better and deeper questions about the increasingly complex interconnections across human and nonhuman worlds, especially given the planetary crises we face today.
This chapter is a journey of thought exploring decolonial critique as a situated practice while thinking through exilic consciousness and its constitutive conditions. I begin by reflecting on decolonialities to gesture toward varied forms of decolonial projects that need to be situated, given that each location generates different sets of questions/problems that demand different answers. In this way, I reconfigure the exilic condition, and the space of displacement in general, as a plurilingual space that unsettles various colonial forms of epistemic monolingualism predicated on the selfsufficiency of thought. To this end, I reflect on the potentiality of exilic consciousness to generate decolonial critique when thinking from/about the Global South. Finally, this chapter demonstrates the significance of acknowledging the diverse locations and trajectories of decolonial critique and the plurality of thought embedded within the exilic intellectual formation that can potentially undo colonial forms of knowledge-making and being in the world.
In this reflection piece, I look at the feminist artistic landscape emerging in Berlin with its growing, diverse migrant community. I examine the ways in which women* artists challenge the imposed notions of their migrant status in the city and their states of belonging within it. I demonstrate this through two feminist initiatives I have been involved in that aim to amplify the voices of women* artists whose creative practices disrupt carefully constructed frameworks relating to borders of inclusion and exclusion. I argue that the artistic practices of women* in these networks are killjoy because they unapologetically get in the way, dismantling carefully constructed frameworks that delineate borders of inclusion and exclusion. By reflecting on homemaking practices in exile, I exemplify how feminisms from the global south decentralize claims to truth by taking the means of production into their own hands. By framing the chapter around the recent protests in Berlin unfolding in solidarity with the feminist revolution in Iran, I reveal the possible limits of such actions when they do not embrace intersectionality. Ultimately, I propose to invest in feminist artistic practices that destabilize exclusionary politics by creating visibility and bridging theory and practice.
The ICH M13A draft bioequivalence guideline allows the exclusion of very low plasma profiles from the statistical evaluation in exceptional cases, i.e., if such phenomenon occurs due to non-compliance of subjects (not swallowing the product). Moreover, the draft ICH guideline requests additional bioequivalence studies for medicinal products with pH-dependent solubility after concomitant administration of gastric pH modifying preparations, e.g., proton pump inhibitors. Both regulations are scientifically sound, however, would need further specification. Main problem in this context is that compounds with very low solubility and slow intrinsic dissolution in the intestinal environment will cause significant bioavailability problems if their solid oral dosage forms are emptied from the stomach undisintegrated. Also very low plasma profiles may result under these circumstances. Such cases can occur accidentally and are not resultant of non-compliance. Thus, limitation for one case per study only as suggested in the guideline is not justified.
Nicotinamide adenine dinucleotide (NAD) serves as a cap-like structure on cellular RNAs (NAD-RNAs) in all domains of life including the bacterium Escherichia coli. NAD also acts as a key molecule in phage-host interactions, where bacterial immune systems deplete NAD to abort phage infection. Nevertheless, NAD-RNAs have not yet been identified during phage infections of bacteria and the mechanisms of their synthesis and degradation are unknown in this context. The T4 phage that specifically infects E. coli presents an important model to study phage infections, but a systematic analysis of the presence and dynamics of NAD-RNAs during T4 phage infection is lacking. Here, we investigate the presence of NAD-RNAs during T4 phage infection in a dual manner. By applying time-resolved NAD captureSeq, we identify NAD-capped host and phage transcripts and their dynamic regulation during phage infection. We provide evidence that NAD-RNAs are – as reported earlier – generated by the host RNA polymerase by initiating transcription with NAD at canonical transcription start sites. In addition, we characterize NudE.1 – a T4 phage-encoded Nudix hydrolase – as the first phage-encoded NAD-RNA decapping enzyme. T4 phages carrying inactive NudE.1 display a delayed lysis phenotype. This study investigates for the first time the dual epitranscriptome of a phage and its host, thereby introducing epitranscriptomics as an important field of phage research.
Therapierefraktärer Schmerz ist ein weit verbreitetes, äußerst belastendes Leitsymptom rheumatischer Erkrankungen. Viele Betroffene weichen daher bei Versagen der Standardmedikation selbstständig auf Cannabis oder die strukturell verwandte Substanz Palmitoylethanolamid (PEA) als Add-On- oder Alternativtherapie aus, obwohl dies in Deutschland bisher nur eingeschränkt zulässig ist. Die deutsche Gesetzgebung ist diesbezüglich nicht eindeutig, weshalb Ärzt:innen in ihrer Entscheidung, Cannabis zu verschreiben, auf Leitlinien, Fallberichte und Expert:innenmeinungen zurückgreifen müssen. Dies führt zu schwierigen Einzelfallentscheidungen, da sich die derzeitige Datenlage zu Cannabis-based Medicine (CBM) bzw. PEA und Rheuma als mangelhaft darstellt und die Leitlinien dementsprechend keine klaren Empfehlungen enthalten. Ziel der vorliegenden Arbeit ist es, die vorhandene Evidenz zusammenzufassen, zu ordnen und anhand der Hill-Kriterien den möglichen kausalen Zusammenhang zwischen der Einnahme von CBM bzw. PEA und der analgetischen Wirkung bei Rheumaschmerzen zu prüfen.
In high light, the antenna system in oxygenic photosynthetic organisms switches to a photoprotective mode, dissipating excess energy in a process called non-photochemical quenching (NPQ). Diatoms exhibit very efficient NPQ, accompanied by a xanthophyll cycle in which diadinoxanthin is de-epoxidized into diatoxanthin. Diatoms accumulate pigments from this cycle in high light, and exhibit faster and more pronounced NPQ. The mechanisms underlying NPQ in diatoms remain unclear, but it can be mimicked by aggregation of their isolated light-harvesting complexes, FCP (fucoxanthin chlorophyll-a/c protein). We assess this model system by resonance Raman measurements of two peripheral FCPs, trimeric FCPa and nonameric FCPb, isolated from high- and low-light-adapted cells (LL, HL). Quenching is associated with a reorganisation of these proteins, affecting the conformation of their bound carotenoids, and in a manner which is highly dependent on the protein considered. FCPa from LL diatoms exhibits significant changes in diadinoxanthin structure, together with a smaller conformational change of at least one fucoxanthin. For these LL-FCPa, quenching is associated with consecutive events, displaying distinct spectral signatures, and its amplitude correlates with the planarity of the diadinoxanthin structure. HL-FCPa aggregation is associated with a change in planarity of a 515-nm-absorbing fucoxanthin, and, to a lesser extent, of diadinoxanthin. Finally, in FCPb, a blue-absorbing fucoxanthin is primarily affected. FCPs thus possess a plastic structure, undergoing several conformational changes upon aggregation, dependent upon their precise composition and structure. NPQ in diatoms may therefore arise from a combination of structural changes, dependent on the environment the cells are adapted to.
The spike protein of SARS-CoV-2 is a highly flexible membrane receptor that triggers the translocation of the virus into cells by attaching to the human receptors. Like other type I membrane receptors, this protein has several extracellular domains connected by flexible hinges. The presence of these hinges results in high flexibility, which consequently results in challenges in defining the conformation of the protein. Here, We developed a new method to define the conformational space based on a few variables inspired by the robotic field’s methods to determine a robotic arm’s forward kinematics. Using newly performed atomistic molecular dynamics (MD) simulations and publicly available data, we found that the Denavit-Hartenberg (DH) parameters can reliably show the changes in the local conformation. Furthermore, the rotational and translational components of the homogenous transformation matrix constructed based on the DH parameters can identify the changes in the global conformation of the spike and also differentiate between the conformation with a similar position of the spike head, which other types of parameters, such as spherical coordinates, fail to distinguish between such conformations. Finally, the new method will be beneficial for looking at the conformational heterogeneity in all other type I membrane receptors.
We present a new experimental dataset on the impact of the heavy halogens chlorine, bromine and iodine on the Raman water bands concerning pressure and their concentration at room temperature. These experiments were conducted at ambient temperature, with variations in halogen concentration and pressure ranging from 0 to 1.4 GPa.
The strength of the Raman water band shift change increases with the ionic size from chlorine, over bromine, to iodine. Our experiments further demonstrate that increased pressure diminishes the impact of the halogen shift change to a varying extent for each of the three halogens. This finding can have significant implications for the salinity calculation of fluid inclusions in minerals such as quartz or olivine. Particularly in the low salinity range, the concentration can be markedly underestimated if the pressure effect is neglected. For experiments in diamond anvil cells involving halogens dissolved in water, the change in Raman water band shifts can serve either as a new tool to monitor pressure, or to monitor the salinity.
Diversität und Diskurs – Wie (un-)politisch ist die Universität? : Ringvorlesung im Sommersemester
(2024)
We carry out an in-depth analysis of the prompt-collapse behaviour of binary neutron star (BNS) mergers. To this end, we perform more than 80 general relativistic BNS merger simulations using a family of realistic Equations of State (EOS) with different stiffness, which feature a first order deconfinement phase transition between hadronic and quark matter. From these simulations we infer the critical binary mass Mcrit that separates the prompt from the non-prompt collapse regime. We show that the critical mass increases with the stiffness of the EOS and obeys a tight quasi-universal relation, Mcrit/MTOV ≈ 1.41 ± 0.06, which links it to the maximum mass MTOV of static neutron stars, and therefore provides a straightforward estimate for the total binary mass beyond which prompt collapse becomes inevitable. In addition, we introduce a novel gauge independent definition for a one-parameter family of threshold masses in terms of curvature invariants of the Riemann tensor which characterizes the development toward a more rapid collapse with increasing binary mass. Using these diagnostics, we find that the amount of matter remaining outside the black hole sharply drops in supercritical mass mergers compared to subcritical ones and is further reduced in mergers where the black hole collapse is induced by the formation of a quark matter core. This implies that Mcrit, particularly for merger remnants featuring quark matter cores, imposes a strict upper limit on the emission of any detectable electromagnetic counterpart in BNS mergers.
Vielfalt im Hochschulsport
(2024)
Zum Sommersemester hat das Team vom Zentrum für Hochschulsport (ZfH) der Goethe-Universität wieder ein vielfältiges und buntes Programm auf die Beine gestellt. Dazu gehören natürlich Klassiker wie Fußball oder Volleyball, aber auch Trendsportarten und exotische Disziplinen. Einiges davon ist auch im laufenden Semester noch buchbar! Im Folgenden werden einige Angebote kurz beschrieben.
Spezialwissen für SCALE
(2024)
Volker Zickermann und Eric Helfrich sind bei der Exzellenzcluster-Initiative SCALE (Subcellular Architecture of Life) dabei und werden dort ihre Expertise einbringen. Das Spezialgebiet des einen ist ein Proteinkomplex in den Mitochondrien, den Kraftwerken der Zelle. Der andere sucht schwerpunktmäßig bisher unbekannte Naturstoffe, die die Basis für neue Antibiotika sein könnten.
Herzforschung meets KI
(2024)
Moderne Methoden der Künstlichen Intelligenz (KI) spielen in der Wissenschaft eine immer größere Rolle. Wie Forscher des Exzellenzclusters Cardio-Pulmonary Institute (CPI) KI in der Herzbildgebung nutzen, zeigte Professor Eike Nagel im Rahmen der Bürgeruniversität der Goethe-Universität. Er leitet das Institut für experimentelle und translationale kardiovaskuläre Bildgebung am Fachbereich Medizin und forscht an der Entwicklung verbesserter Behandlungsmöglichkeiten für Herz-Kreislauf-Erkrankungen. Mit dem Ziel, seine Forschung für alle Menschen zugänglich und verständlicher zu machen, lud Prof. Nagel interessierte Bürger*innen am 10. Mai in sein Institut ein.