31325 research outputs found
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Konzeption eines Spiels zum Thema Data Tracking in der Wissenschaft, speziell von wissenschaftlichen Verlagen für naturwissenschaftliche Early Career Researcher an Institutionen
No full textPublizieren ist für Wissenschaftler*innen essentiell. Dabei ist es heutzutage kaum möglich, an digitalen Angeboten vorbeizukommen. Nur wenigen Forschenden ist dabei bewusst, dass auch bei digitalen Verlagsangeboten persönliche Daten getrackt und missbraucht werden können. Ein Auftrag von Bibliotheken ist es, Forschende zu unterstützen und Informationskompetenz zu stärken. Deshalb fällt das Stärken von Bewusstsein für Data Tracking durch wissenschaftliche Verlage in ihr Aufgabengebiet. Dies kann unter anderem durch Workshops passieren. Unsere Frage hierbei ist, wie Wissenschaftler*innen, speziell Early Career Researchers in den Naturwissenschaften, Datentracking durch wissenschaftliche Verlage, die negativen Auswirkungen und Abwehrmöglichkeiten gegen Datentracking vermittelt werden können. In unserem Workshop-Konzept haben wir zusätzlich zu Kurzvorträgen ein Spiel als eine simulationsbasierte Aufgabe mit Rollenspiel-ähnlichen Merkmalen entwickelt, das auf einem Entdecken-lassenden-Ansatz basiert. Mithilfe dessen wird ein realitätsnaher Publikationsprozess durchgespielt. Hier werden, abhängig von den getroffenen Entscheidungen, personenbezogene Daten getrackt. Dieses Konzept wurde in einem Pre-ISI-Workshop (ISI = Internationales Symposium für Informationswissenschaft) am 17. März 2025 vorgestellt und durchgeführt; das prototypische Kartenspiel wurde getestet und Feedback eingeholt. Dieses Kartenspiel wird für die Weiterverwendung (und Weiterentwicklung) als Open Educational Resource freigegeben. Mögliche Anpassungen sind beispielsweise, den Workshop auch auf Studierende auszurichten und ihnen so den Publikationsprozess oder den Schreibprozess von wissenschaftlichen Arbeiten spielerisch darzustellen.No researcher can avoid publishing. Nowadays, it is almost impossible to avoid digital publication services. Not many people are aware that personal data can be tracked by academic publishers without the knowledge of the user and, in the worst case, misused. One of the missions of libraries is to support researchers and foster information literacy. Awareness of data tracking in scholarly publishing houses falls within this scope. This can, for instance, be communicated through workshops. The question here is, how scientists, especially early career researchers in natural sciences, can be educated about data tracking by scholarly publishing houses, along with its negative effects and ways to defend against data tracking. In our workshop concept, in addition to short presentations, we have developed a game as a simulation-based task with role-playing game-like features based on a discovery approach. This is used to play through a reality-based publication process. Depending on the decisions made, personal data will be tracked. This concept was presented and implemented in the pre-ISI workshop (ISI = International Symposium on Information Science) on March 17th, 2025, where the prototype card game was tested, and feedback was obtained. The card game will be released for further use (and adaptations) as an open educational resource. Possible adaptations include targeting the workshop towards students and thus presenting the publication process or the writing process of academic papers to them in a playful way.Peer Reviewe
Towards determining the (2+1)-dimensional quantum electrodynamics running coupling with Monte Carlo and quantum computing methods
No full textThe solution of strongly-interacting quantum field theories remains a major challenge in theoretical physics, often requiring numerical solutions. A first-principles approach in this direction is the lattice formulation, where spacetime is approximated with a finite grid. In this work, we examine the case of a compact pure-gauge U (1) lattice gauge theory in (2 + 1) dimensions, presenting a strategy to determine the running coupling of the theory and extracting the non-perturbative Λ -parameter. This is achieved by combining Monte Carlo simulations and quantum computing techniques, matching the expectation value of the plaquette operator. We also present results for the static potential and static force, which can be related to the renormalized coupling. The outlined procedure can be extended to other Abelian and non-Abelian lattice gauge theories with matter fields, and might provide a way towards studying lattice quantum chromodynamics utilizing both quantum and classical methods.Helmholtz Association501100009318Ministerium für Wissenschaft, Forschung und Kultur (Brandenburg Ministry of Sciences, Research and Cultural Affairs)501100004581Helmholtz Association —“Innopool Project Variational Quantum Computer Simulations (VQCS).” Ministry of Science, Research and Culture of the State of Brandenburg within the Centre for Quantum Technologies and Applications (CQTA).DFG, German Research Foundation: CRC 1639 NuMeriQS – project no. 511713970Peer Reviewe
Phenolic Leaf Compounds in Ash Trees (Fraxinus excelsior L.) in the Context of Ash Dieback
No full textThe article processing charge was funded by the Open Access Publication Fund of Humboldt-Universität zu Berlin.Most ash trees (Fraxinus excelsior) in Germany are infected with Hymenoscyphus fraxineus, the causative agent of ash dieback (ADB). This study investigates the phenolic content of ash leaves to evaluate their potential as indicators for monitoring ADB and to assess how this potential is affected by site and year. Fresh leaf samples were collected and immediately frozen from 14 forest plots across Germany over a period of up to four years. Phenolic compounds were quantified using both photometric assays and HPLC. The results reveal strong site-specific differences in both total phenolic content and individual phenolic profiles. Temporal differences between sampling years were less pronounced, but were frequently significant. In contrast, crown condition—a key indicator of ADB damage—had only a weak effect on phenolic content. This suggests that mature ash trees do not exhibit a clear phenol-based defence response to H. fraxineus under field conditions. Our findings underscore the complexity of phenolic dynamics in natural stands and demonstrate that no robust of phenolic biomarker for ADB could be identified in mature trees.Peer Reviewe
Modularity of formal Fourier–Jacobi series from a cohomological point of view
No full textIn dieser Dissertation untersuchen wir die Modularität formaler Fourier–Jacobi-Reihen, sowohl im klassischen Rahmen über C als auch im arithmetischen Rahmen über Z. Dies erfolgt, indem wir kohomologische Verschwindungssätze für Geradenbündel herleiten, die auf einer toroidalen Kompaktifizierung des Modulraums Ag von prinzipal polarisierten abelschen Schemata der relativen Dimension g definiert sind.In this thesis, we investigate the modularity of formal Fourier–Jacobi series, both in the classical setting over C and in the arithmetic setting over Z, by
establishing cohomological vanishing results for line bundles defined on a toroidal compactification of the moduli space Ag of principally polarized abelian schemes of relative dimension g
Multi-targeted azacoumarin–cyanocinnamate hybrids induce G2/M arrest and apoptosis via tubulin, and COX-2/VEGFR modulation: insights from in vitro mechanistic basis and in vivo validation
No full textCancer remains a significant global health concern, with breast cancer ranking among the leading causes of cancer-related mortality in women. In pursuit of multi-targeted anticancer agents, we designed and synthesized a novel series of 7-hydroxy azacoumarin–α-cyanocinnamate hybrids and evaluated their therapeutic potential through comprehensive in vitro and in vivo studies. Structural characterization was confirmed using NMR, IR, and elemental analysis. Among the synthesized compounds, compound 7 exhibited the most potent cytotoxic activity against MCF-7 cells (IC50 = 7.65 μM) and MDA-MB-231 (IC50 = 9.7 ± 1.15 μM), with notable selectivity over non-tumorigenic MCF-10A cells (IC50 = 52.02 μM), as compared to the reference drug doxorubicin. Mechanistic in vitro investigations revealed that compound 7 induced G2/M phase arrest and apoptosis, accompanied by upregulation of pro-apoptotic markers (Bax, p53) and suppression of Bcl-2. Additionally, compound 7 significantly inhibited tubulin polymerization and demonstrated marked antioxidant activity in the FRAP assay (IC50 = 144.71 μM), as well as selective COX-2 inhibition (IC50 = 1.264 μM, SI = 5.93). In vivo evaluation using the Ehrlich ascites carcinoma (EAC) model confirmed its anticancer efficacy, with 85.92% reduction in viable EAC cells and substantial tumor volume suppression at 10 mg kg−1. Notably, compound 7 mitigated EAC-induced hepatorenal toxicity by restoring liver and kidney biomarkers and reducing oxidative stress and lipid peroxidation. Furthermore, it significantly downregulated pro-inflammatory (TNF-α) and angiogenic (VEGFR-II) markers while preserving normal tissue histoarchitecture. Collectively, these findings highlight compound 7 as a promising multi-functional lead candidate with cytotoxic, antioxidant, anti-inflammatory, and anti-angiogenic activities, meriting further development in cancer therapeutics.Princess Nourah Bint Abdulrahman University 10.13039/501100004242Peer Reviewe
Expression of boundary-crossing motion events among adults and children in German and Turkish
No full textDiese Dissertation untersucht die Lexikalisierung von Bewegungsereignissen mit Grenzübertretungen bei Erwachsenen und vierjährigen Kindern im Deutschen und Türkischen. Es werden drei Grenzübertretungs-Path-Typen unterschieden: enclosure-type, axial-type und traversal-type Paths. Während axial- und enclosure-type Paths als dreidimensional angenommen werden, gelten traversal-type Paths als ein- oder zweidimensional. Mittels eines videobasierten Produktionsexperiments wurde geprüft, ob Path-Realisierung bei Grenzübertretungs-Paths häufiger auftritt als bei Nicht-Grenzübertretungs-Paths. Dreidimensionale Grenzübertretungs-Paths lösen signifikant häufiger Path-Realisierung aus, traversal-type Paths hingegen nicht. Kinder zeigen bereits sprachspezifische Muster bei den Prozentsätzen der Manner- und Path-Verben. Jedoch unterscheiden sich deutsche Kinder und Erwachsene in bevorzugten Satellitenstrukturen: Erwachsene nutzen meist das Satellit hin, Kinder die r-Adpositionskonstruktion, die als Eins-zu-eins-Realisierung von BECOME und end-location change interpretiert wird. Unterschiede lassen sich dadurch erklären, dass Kinder BECOME und end-location change transparenter realisieren, während Registereffekte nicht ausgeschlossen werden können. Deutsche Erwachsene produzieren mehr Ground-containing-Phrasen als türkische; deutsche Kinder weniger als Erwachsene, türkische Kinder unterscheiden sich nicht von Erwachsenen. Türkische Kinder verwenden mehr neutrale Verben, die, laut meiner Behauptung, eine Pathkomponente realisieren; deutsche Kinder greifen seltener auf diese Strategie zurück, da Path im Deutschen auch außerhalb des Verbs realisiert werden kann.This dissertation investigates the lexicalization of motion events involving boundary crossings in adults and four-year-old children in German and Turkish. Three types of boundary-crossing paths are distinguished: enclosure-type, axial-type, and traversal-type paths. Axial- and enclosure-type paths are considered three-dimensional, whereas traversal-type paths are viewed as one- or two-dimensional. Using a video-based production experiment, it was tested whether path realization occurs more frequently for boundary-crossing paths than for non-boundary-crossing paths. Three-dimensional boundary-crossing paths trigger path realization significantly more often, whereas traversal-type paths do not. Children already show language-specific patterns in the percentages of manner and path verbs. German children and adults differ in their preferred satellite constructions: adults mostly use the satellite hin, while children prefer the r-adposition construction, which is interpreted as a one-to-one realization of BECOME and end-location change. These differences can be explained by the fact that children realize BECOME and end-location change more transparently, although the register effect cannot be ruled out. German adults produce more ground-containing phrases than Turkish adults; German children produce fewer than adults, while Turkish children do not differ from adults. Turkish children use more neutral verbs, which, according to my claim, realize a path component; German children rely less on this strategy, since path can also be realized outside the verb in German
Combining Crown Structures for Vulnerability Measures
No full textOver the past decades, various metrics have emerged in graph theory to grasp the complex nature of network vulnerability. In this paper, we study two specific measures: (weighted) vertex integrity (wVI) and (weighted) component order connectivity (wCOC). These measures not only evaluate the number of vertices that need to be removed to decompose a graph into fragments, but also take into account the size of the largest remaining component. The main focus of our paper is on kernelization algorithms tailored to both measures. We capitalize on the structural attributes inherent in different crown decompositions, strategically combining them to introduce novel kernelization algorithms that advance the current state of the field. In particular, we extend the scope of the balanced crown decomposition provided by Casel et al. [ 1 ] and expand the applicability of crown decomposition techniques. In summary, we improve the vertex kernel of VI from to , and of wVI from to , where represents the weight of the heaviest component after removing a solution. For wCOC we improve the vertex kernel from to , where . We also give a combinatorial algorithm that provides a 2 kW vertex kernel in fixed-parameter tractable time when parameterized by r , where is the size of a maximum -packing. We further show that the algorithm computing the 2 kW vertex kernel for COC can be transformed into a polynomial algorithm for two special cases, namely when , which corresponds to the well-known vertex cover problem, and for claw-free graphs. In particular, we show a new way to obtain a 2 k vertex kernel (or to obtain a 2-approximation) for the vertex cover problem by only using crown structures.Open Access funding enabled and organized by Projekt DEAL.Hasso-Plattner-Institut für Digital Engineering gGmbH (4420)Peer Reviewe
Solar power, land control, and Indigenous resistance in Yucatán, Mexico
No full textThis article examines the suspension of the Yucatán Solar PV park, a project awarded through Mexico’s first long-term power auction, situating it within the broader context of the country’s energy reform and its implications for Indigenous territories. Drawing on ethnographic fieldwork and informed by political ecology and critical agrarian studies, the study analyzes how legal instruments, spatial tools, and discursive practices are deployed to render Maya territory investable for solar development. Central to the analysis are the dynamics of land acquisition, which reveal the land's profound social, cultural, and ecological significance for Maya communities, including the location of a sacred site. These dynamics exemplify green grabbing as an initial phase in the contested processes of land control. The article outlines the mechanisms of legitimation through which actors seek to consolidate authority over land, as well as the counter-processes of resistance, legal action, and competing territorial claims that ultimately led to the project’s suspension. The study considers the wider implications of the suspension for the social fabric and ecological integrity of surrounding communities, offering critical insights into the contested politics of land control and territorial transformation under green capitalism, and how grassroots resistance can disrupt these trajectories.Open Access funding enabled and organized by Projekt DEAL.Consejo Nacional de Ciencia y Tecnologíahttp://dx.doi.org/10.13039/501100003141Humboldt-Universität zu Berlin (1034)Peer Reviewe
Zweite Änderung der fachspezifischen Studien- und Prüfungsordnung für den internationalen Masterstudiengang Europäisches Recht und Rechtsvergleich (AMB Nr. 30/2017)
No full textQuery Decomposition for Distributed Complex Event Processing
No full textComplex Event Processing (CEP) Systeme evaluieren Abfragen über hochfrequenten Ereignisströmen, um relevante Muster darin zu erkennen. In Szenarien mit verteilten Ereignisquellen, etwa in Sensornetzwerken oder IoT-Anwendungen, gewinnt CEP zunehmend an Bedeutung. Bestehende Ansätze nutzen das Optimierungspotenzial in solchen Netzwerken nur begrenzt aus. Diese Dissertation stellt Techniken zur Optimierung verteilter Mustererkennung vor, die darauf abzielen, die Netzwerkkosten, also die Anzahl der im Netzwerk ausgetauschten Nachrichten, zu minimieren. Dazu nutzen wir sowohl die Semantik der Abfragesprache als auch Netzwerkeigenschaften aus. Insbesondere führen wir eine Dekompositionstechnik von Mustern ein, mit der korrekte Teilmuster spezifiziert und für die verteilte Erkennung genutzt werden können. Darauf aufbauend führen wir Modelle für die verteilte Mustererkennung in Netzwerken ein: MuSE- und INEv-Graphen. Während MuSE-Graphen eine vollständige Netzwerktopologie voraussetzen, erlauben INEv-Graphen beliebige Netzwerktopologien und spezifizieren die effizienten Weiterleitung von Ereignissen. Zusätzlich untersuchen wir die Ereignisübertragung. Während Ereignisse üblicherweise sofort nach ihrer Generierung versandt werden, können Kommunikationskosten reduziert werden, indem die Übertragung erst durch eine Anfrage geschieht. Hierzu führen wir PrePP-Pläne ein, die die Anfrage-basierte Übertragung von Ereignissen mit Prädikat-basierter Filterung modellieren. Schließlich übertragen wir unsere Dekompositionstechniken auf die parallele Mustererkennung. Dabei analysieren wir Durchsatzengpässe bei Rechenknoten und entwickeln ein Kostenmodell zur Musterdetektion in Clusterumgebungen. Die resultierenden DecoPa-Pläne ermöglichen eine durchsatzoptimierte, parallele Mustererkennung. Für alle Modelle definieren wir formale Eigenschaften, beweisen Korrektheit und geben Konstruktionsalgorithmen an. Experimente zeigen die Überlegenheit unserer Ansätze gegenüber bestehenden Verfahren.Complex Event Processing (CEP) systems continuously evaluate query workloads over event streams to detect relevant patterns. Recently, CEP has gained importance in settings with distributed event sources, such as sensor networks or IoT environments. While distributed query evaluation enables performance optimization, existing approaches do not tap into the potential of truly distributed CEP. This dissertation introduces a framework to optimize distributed query evaluation for CEP, focusing on minimizing network costs through query semantics and network characteristics. We introduce Multi-Sink Evaluation (MuSE) graphs and In-Network Evaluation (INEv) graphs for in-network CEP processing. MuSE graphs assume fully connected topologies; INEv graphs generalize to arbitrary ones by incorporating strategies for efficient event forwarding and output selection, allowing the reuse of disseminated events. We also explore the complementary aspect of event transmission. While commonly the event exchange follows a push-based mechanism, pull-based communication reduces costs by sending events only upon request. We introduce predicate-based push-pull (PrePP) plans that use pull-based filtering to improve efficiency. Finally, we apply our findings on in-network query evaluation to tackle parallel CEP query processing. While bandwidth constraints heavily influence performance in event sourced networks, in cluster-based environments throughput and latency are critical. We show that the ingestion and comparison rates of processing units are key for throughput optimization. Based thereon, we develop a cost model to guide query workload decomposition and introduce Decomposition-based Parallel (DecoPa) plans to enable efficient, parallel CEP processing. We formally define each model, prove correctness, and provide construction algorithms. Experiments show that our methods outperform existing techniques across cost metrics, enabling scalable, distributed CEP over event streams