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Dissecting the Value Premium
Get PDFThe cumulative dissertation explores the value premium and its impact and dynamics within both nonfinancial and the real estate equities. The three research papers included provide a comprehensive analysis of the subject matter. These papers cover various aspects of financial research, including an analysis of value-growth strategies based on expectation errors, an examination of the cash premium in the real estate market, and a comprehensive decomposition of the value premium of real estate equities
Universal Correlations in Chaotic Many-Body Quantum States: Fock-Space Formulation of Berry’s Random Wave Model
Get PDFThe apparent randomness of chaotic eigenstates in interacting quantum systems hides subtle correlations dynamically imposed by their finite energy per particle. These correlations are revealed when Berry’s approach for chaotic eigenfunctions in single-particle systems is lifted into many-body space. We achieve this by a many-body semiclassical analysis, appropriate for the mesoscopic regime of a large but finite number of particles. We thereby identify as signatures of chaotic many-body eigenstates the universality of both their cross-correlations and the Gaussian distribution of expansion coefficients. Combined, these two features imprint characteristic features to the morphology of eigenstates that we check against extensive quantum simulations. The universality of eigenstate correlations for fixed energy density is hence a further signature of many-body quantum chaos that, while consistent with the eigenstate thermalization hypothesis, lies beyond random matrix theory
Evaluating ChatGPT, Gemini and other Large Language Models (LLMs) in orthopaedic diagnostics: A prospective clinical study
Get PDFBackground: Large Language Models (LLMs) such as ChatGPT are gaining attention for their potential applications
in healthcare. This study aimed to evaluate the diagnostic sensitivity of various LLMs in detecting hip or
knee osteoarthritis (OA) using only patient-reported data collected via a structured questionnaire, without prior
medical consultation.
Methods: A prospective observational study was conducted at an orthopaedic outpatient clinic specialized in hip
and knee OA treatment. A total of 115 patients completed a paper-based questionnaire covering symptoms,
medical history, and demographic information. The diagnostic performance of five different LLMs—including
four versions of ChatGPT, two of Gemini, Llama, Gemma 2, and Mistral-Nemo—was analysed. Model-generated
diagnoses were compared against those provided by experienced orthopaedic clinicians, which served as the
reference standard.
Results: GPT-4o achieved the highest diagnostic sensitivity at 92.3 %, significantly outperforming other LLMs.
The completeness of patient responses to symptom-related questions was the strongest predictor of accuracy for
GPT-4o (p < 0.001). Inter-model agreement was moderate among GPT-4 versions, whereas models such as
Llama-3.1 demonstrated notably lower accuracy and concordance.
Conclusions: GPT-4o demonstrated high accuracy and consistency in diagnosing OA based solely on patientreported
questionnaires, underscoring its potential as a supplementary diagnostic tool in clinical settings.
Nevertheless, the reliance on patient-reported data without direct physician involvement highlights the critical
need for medical oversight to ensure diagnostic accuracy. Further research is needed to refine LLM capabilities
and expand their utility in broader diagnostic applications
Biliquid oil-in-water nanofoams and spontaneous emulsification obtained with a surfactant resistant to curvature changes
Get PDFHypothesis
Due to its huge polar headgroup, octaoxyethylene octyl ether carboxylic acid (C8E8CH2COOH = Akypo LF2™) is supposed not to be able to change its curvature sufficiently to form bicontinuous microemulsions. Instead, upon adding an oil to the binary water – surfactant system, excess oil could be squeezed out or a biliquid foam could form.
Experiments
An auto-dilution setup was used to record small-angle X-ray scattering data along six dilution lines in the newly established phase diagram of the ternary system 2-ethylhexanol – C8E8CH2COOH – water.
Results
Evaluation of the data in combination with the recorded phase diagram revealed that the ternary microemulsions with a slightly amphiphilic oil indeed do not show a classical structural inversion via a bicontinuous structure with increasing oil content, but instead the sequence: O/W micelles – O/W biliquid nanofoam – molecular co-solubilization in the oil phase. The biliquid nanofoam structure with 102–104 oil molecules enclosed by locally flat layers of interdigitated hydrated headgroups exists in the middle of the phase diagram. We may speculate that this phase can be used as a multitude of nanocontainers, e.g., for chemical reactions in an aqueous environment, but with negligible water chemical potential. In the vicinity of the critical point, spontaneous formation of stable mesoscale droplets (an “Onuki-like” structure, as known with antagonistic salts) is detected in a region showing a pronounced Tyndall effect
Control of biomedical nanoparticle distribution and drug release in vivo by complex particle design strategies
Get PDFThe utilization of targeted nanoparticles as a selective drug delivery system is a powerful tool to increase the amount of active substance reaching the target site. This can increase therapeutic efficacy while reducing adverse drug effects. However, nanoparticles face several challenges: upon injection, the immediate adhesion of plasma proteins may mask targeting ligands, thereby diminishing the target cell selectivity. In addition, opsonization can lead to premature clearance and the widespread presence of receptors or enzymes limits the accuracy of target cell recognition. Nanoparticles may also suffer from endosomal entrapment, and controlled drug release can be hindered by premature burst release or insufficient particle retention at the target site. Various strategies have been developed to address these adverse events, such as the implementation of switchable particle properties, regulating the composition of the formed protein corona, or using click-chemistry based targeting approaches. This has resulted in increasingly complex particle designs, raising the question of whether this development actually improves the therapeutic efficacy in vivo. This review provides an overview of the challenges in targeted drug delivery and explores potential solutions described in the literature. Subsequently, appropriate strategies for the development of nanoparticular drug delivery concepts are discussed
Ultrafast terahertz nanoscopy of van der Waals quantum materials: from ambient to cryogenic conditions
No full textAtomically thin van der Waals materials host exciting optoelectronic phenomena governed by reduced dimensionality and electronic correlations. Fabricating new heterostructures by stacking multiple monolayers under controlled twist angles has enabled the design of new quantum phases of matter. Yet, strain, doping or dielectric disorder can modulate the optical properties on the nanoscale. To exploit the full potential of the material platform, these subwavelength inhomogeneities inaccessible to most diffraction-limited probes and their impact on the ultrafast exciton dynamics, for example, need to be resolved. In this work, we build on established ultrafast near-field microscopy techniques and further develop new tools for investigating van der Waals structures with subcycle temporal and nanometer spatial resolution.
First, we quantify density-dependent excitonic phases in atomically thin transition metal dichalcogenide layers using polarization nanoscopy at ambient conditions. To this end, the ultrafast recombination dynamics of photo-generated electron-hole pairs in an artificially stacked tungsten diselenide bilayer is monitored by probing the evolution of the local polarizability of these charge carriers with evanescent terahertz fields. A characteristic change in the recombination dynamics reveals an exciton Mott transition from an optically dark species into an electron-hole plasma. The nanometer spatial resolution allows us to circumvent inhomogeneous broadening and to reveal the continuous nature of the transition, which is fully corroborated by many-body calculations.
Second, we introduce an ultra-stable, cryogenic near-field microscopy system, which enables multi-terahertz nanoscopy under ultrahigh-vacuum conditions and at liquid helium temperatures. This combination facilitates unprecedented sub-nanometer oscillation amplitudes of the tip in near-field microscopy. Thus, we trace extremely confined electric fields on the surface of a noble metal, which exhibit a decay constant of only 150 picometers and give rise to a phase shift of the scattered light of almost 90° across angstrom-scale tip-sample distances – indications of a novel regime beyond established analytical scattering models. This proof of principle promises access to the optical response of van der Waals systems with atom-scale spatial resolution. The feasibility of this approach is further verified with several experiments including the visualization of moiré superlattices, topologically protected surface states and charge-density-wave phase transitions in real space.
Finally, this setup is extended by a femtosecond laser system to establish combined ultrafast, cryogenic near-field microscopy and lightwave-driven scanning tunneling microscopy. In the future, this unique nano-videography toolbox will allow for recording charge carrier dynamics in van der Waals systems on record-breaking spatiotemporal scales
Stellenwert des Kontrastmittelultraschalls in der Nierenbildgebung im Vergleich zur konventionellen Bildgebung
No full textGemäß den EFSUMB-Leitlinien weist CEUS eine ausgezeichnete Genauigkeit bei der Beurteilung von Nierenzysten, soliden Nierenraumforderungen, Nierenperfusionveränderungen und infektiösen Nierenveränderungen auf.
Hinsichtlich der Beurteilung von Nierenzysten könnte eine CEUS-Bosniak-Klassifizierung, wie bereits 2020 von der EFSUMB vorgeschlagen, die Genauigkeit von CEUS und die intermodale Vergleichbarkeit weiter verbessern. Insgesamt sollte CEUS als erste Modalität für die Beurteilung von Nierenzysten eingesetzt werden und nur bei Bosniak-III- und IV-Zysten sollte eine zusätzliche Schnittbildgebung durchgeführt werden, um die Notwendigkeit einer operativen Behandlung zu beurteilen.
Bei soliden Nierenläsionen kann eine initiale Kontrastmittelultraschalluntersuchung den Bedarf an Schnittbildgebungen reduzieren und weitere Informationen liefern, falls bereits eine solide Nierenraumforderung identifiziert wurde, insbesondere bei schlecht durchbluteten papillären Nierenzellkarzinomen. CEUS zeigte auch Vorteile gegenüber CECT bei der Beurteilung kleiner Nierenmassen.
Bei infektiösen und perfusionsbedingten Veränderungen in der Niere sollte CEUS als Goldstandard etabliert werden und zusätzliche Schnittbildgebungen sollte nur bei schlechten Untersuchungsbedingungen eingesetzt werden
[P13-1-jD] Multizentrische Analyse von Bestrahlungsplänen bei Salvage-Bestrahlung von Prostatalogen
No full textFragestellung: Die Salvage-Bestrahlung ist eine etablierte Therapieoption bei biochemischem Rezidiv nach primärer Resektion von Prostatakarzinomen. Die Einhaltung definierter Dosis-Volumenziele ist entscheidend zur Minimierung von Nebenwirkungen und Maximierung der therapeutischen Effizienz. Diese multizentrische Studie analysiert Bestrahlungspläne bayerischer Universitätskliniken anhand von Score-Cards, die auf der RADICALS-HD Studie basieren.
Methodik: In einer retrospektiven Studie wurden Bestrahlungspläne aus drei bayerischen Universitätskliniken in ProKnow® (Elekta, Stockholm, Schweden) ausgewertet. Die Patienten erhielten eine Salvage-Bestrahlung der Prostataloge (32–35 Fraktionen, 64–68 Gy; bei Lokalrezidiv 70–76,5 Gy). Die RADICALS-HD-Dosis-Volumenziele dienten zur Bewertung der Planqualität.
Ergebnisse: Die Studie umfasste 80 Patienten (Medianalter: 73 Jahre;
57–84 Jahre), behandelt mit VMAT (n=40) oder IMRT (n=40). Der mediane PSA-Wert zu Beginn der Strahlentherapie lag bei 0,18 ng/ml (0,03–12,7 ng/ml). Die Analyse der Dosisverteilung in Blase und Rektum zeigte folgende Ergebnisse: Die mittlere Blasen-Dosis betrug 29,2 Gy (11,7–58,7 Gy). Das Volumen der Blase, das mit ≥60 Gy bestrahlt wurde, lag bei einem Median von 24,2 % (5,7–62,6 %), wobei 95 % der Pläne die RADICALS-Ziele (≤50 %) erfüllten. Das Volumen ≥ 50 Gy betrug median 30,0 % (10,0–76,6 %), und die Zielvorgabe von ≤80 % wurde in allen Fällen eingehalten. Die mittlere Rektum-Dosis betrug 30,7 Gy (14,8–46,1 Gy). Das Volumen des Rektums, das mit ≥30 Gy bestrahlt wurde, hatte einen Median von 46,2 % (13,2–82,2 %), wobei 98,7 % der Pläne die Vorgabe von ≤ 80 % erfüllten. Für Volumina ≥ 50 Gy (Median 26,5 %, 4,8–50,5 %) und ≥60 Gy (Median 16,3 %, 1,9–39,0 %) wurden die Ziele (≤ 60 % bzw. ≤50 %) in 100 % der Fälle erreicht.
Schlussfolgerung: Die multizentrische Analyse mit ProKnow® erwies sich als effektives Werkzeug zur Bewertung von Bestrahlungsplänen. Die RADICALS-HD-Dosis-Volumenziele wurden in der großen Mehrheit der Fälle erfüllt. Dies unterstreicht die hohe Qualität der Salvage-Bestrahlungspläne an bayerischen Universitätskliniken und liefert eine Grundlage für zukünftige standardisierte Qualitätsbewertungen.
Offenlegungserklärung: Die Autoren/Autorinnen erklären, dass kein
Interessenkonflikt besteh
QLF-S: Questionnaire on Perceived Load and Fatigue (State)
No full textThe Questionnaire on Perceived Load and Fatigue serves to assess the experienced strain during the past hour as well as the currently perceived fatigue, each with one item. This is assessed across three domains: cognition, motor / physical domain, and emotions. The QLF-S was developed for use during load capacity testing. The questionnaire has so far been used in a study involving 73 patients with post-COVID syndrome and a healthy control sample of 58 gender- and age-matched individuals. The study was conducted between 2022 and 2024 (Tempfli et al. & Randerath, 2025, submitted). The development of the original questionnaire in German (FBE-S: Fragebogen zu empfundener Belastung und Erschöpfung (Status)) was funded by the Zukunftskolleg of the University of Konstanz. The implementation of the study was supported by the Ministry of Science, Research and the Arts of Baden-Württemberg. The English translation "QLF-S: Questionnaire on Perceived Load and Fatigue (State)" was created at the University of Regensburg in 2025