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Fully Sensitized Upconversion Nanoparticles as Efficient Catalysts for NIR‐Driven UV Photochemistry
Get PDFBiological photosynthesis harnesses energy from multiple photons to drive complex chemical transformations. In contrast, chemical photocatalysis typically relies on single-photon excitation, limiting its applicability in high-energy-demanding reactions. Upconversion nanoparticles (UCNPs), which can convert multiple low-energy near-infrared (NIR) photons into a single higher-energy photon, offer a promising solution. We synthesized and systematically improved NaYbF4:Tm@NaYF4 nanoparticles, focusing on sensitizer concentration, dopant spacing, and shell thickness to enhance ultraviolet (UV) and blue emission. Compared to low doped NaYF4:Yb, Tm systems, our nanoparticles exhibited significantly improved brightness, with a 210-fold enhancement in UV emission at 345 nm. Using these UCNPs as heterogeneous photocatalysts, we achieved efficient [2 + 2] photocycloadditions and Paternò–Büchi reactions under 980 nm excitation, with turnover numbers (TON) exceeding 290,000 and turnover frequencies (TOF) up to 8.52 s−1. Additionally, the UCNP catalysts were readily recoverable. Our results provide a rational framework for tailoring UCNPs for energy-demanding photochemical reactions and establish their potential in synthetic and biomedical applications that require deep-tissue, low-phototoxicity excitation
Open-Access-Infrastrukturen nachhaltig finanzieren. In: open-access.network Blog
No full textDie Entwicklung und der Erfolg von Open Access beruhen maßgeblich auf digitalen Informationsinfrastrukturen, die weltweit von Forschenden, Bibliotheken und anderen Einrichtungen genutzt werden. Diese Infrastrukturen stehen zunehmend unter Druck, da ihre Finanzierung oftmals projektbasiert erfolgt und der Übergang zu einer nachhaltigen, institutionellen oder konsortialen Finanzierung bisher nur in Teilen gelingt. Vor diesem Hintergrund widmete sich das Hands-on Lab dem Thema „Open-Access-Infrastrukturen nachhaltig finanzieren“ auf der 113. BiblioCon am 26. Juni 2025 (Pampel et al., 2025) speziell diesem Thema und versuchte, hier Lösungen aufzuzeigen. Ziel war es, gemeinsam mit Expert*innen und Teilnehmenden Herausforderungen, bestehende Modelle und zukünftige Perspektiven für tragfähige Finanzierungslösungen zu reflektieren und konkrete Entwicklungslinien für die deutsche Informationslandschaft zu skizzieren
Fatigue Protokoll nach motorischer, emotionaler oder kognitiver Belastungssitzung bzw. Entspannung. Deutsche Version.
No full textDas Fatigue-Protokoll wurde entwickelt, um die wahrgenommene Intensität von Erschöpfung nach körperlichen, emotionalen oder kognitiven Belastungssitzungen bzw. nach Entspannungsphasen zu erfassen. Im Fatigue-Protokoll wird die wahrgenommene Intensität von Erschöpfung und Belastung am Sitzungstag selbst und über einen Zeitraum von drei Tagen nach der Sitzung dokumentiert. Die Einschätzung erfolgt auf einer Skala von 0 („keine Erschöpfung/Belastung“) bis 4 („sehr starke Erschöpfung/Belastung“). Das Fatigue-Protokoll unterscheidet zwischen emotionaler, kognitiver und körperlicher Belastung und Erschöpfung
Extragenital endometriosis associated with uterine scar defects
No full textIntroduction
Uterine scar defects result from poor healing of the hysterotomy after cesarean sections (CS), in multiple cases leading to retroflexio uteri and retrograde menstruation. Endometriosis is the probable consequence. Patients often experience overlapping symptoms such as dysmenorrhea, dyspareunia, and infertility.
Material and methods
This study analysed cases of sonographically detected uterine scar defects, subsequently undergoing laparoscopy at the University Clinic St. Hedwig, in Regensburg, between 2020 and 2024. Herefore, surgery reports were reviewed, focusing on extragenital endometriosis, symptoms of Cesarean Scar Disorder (CSD), niche morphology, uterine position, and endometriosis localisation using the #Enzian classification.
Results
Extragenital endometriosis was histologically confirmed in 45 of 94 patients (47.9 %) with symptomatic or large uterine niches. A significant association was found between endometriosis and heavy menstrual bleeding (HMB) (p < 0.001) as well as retroflexio uteri (p = 0.036). Symptoms related to CSD did not differ in patients with or without Endometriosis. Endometriotic implants were primarily located in the peritoneum behind the uterus and sacrouterine ligaments, supporting the hypothesis of retrograde menstruation.
Conclusion
There is significant overlap between the symptoms of endometriosis and CSD. Almost half of the patients with a symptomatic niche were found to have endometriosis, whereby the location of endometriosis supports the hypothesis of retrograde menstruation. However, the patient´s history of complaints is not indicative of the diagnosis of endometriosis. Therefore, all patients with CSD should be offered a laparoscopy and endometriosis surgery. All patients with a previous caesarean section presenting with symptoms of endometriosis should be offered standardised and high-quality niche diagnosis and treatment
Linear and Nonlinear Optical Properties of Molecules from Real-Time Propagation Based on the Bethe–Salpeter Equation
Get PDFWe present a real-time propagation method for computing linear and nonlinear optical properties of molecules based on the Bethe–Salpeter equation. The method follows the time evolution of the one-particle density matrix under an external electric field. We include electron–electron interaction effects through a self-energy model based on the screened exchange approximation. Quasiparticle energies are taken from a prior GW calculation to construct the effective single-particle Hamiltonian, and we represent all operators and wave functions in an atom-centered Gaussian basis. We benchmark the accuracy of the real-time propagation against the standard linear-response Bethe–Salpeter equation by using a set of organic molecules. We find very good agreement when computing linear-response isotropic polarizability spectra from both approaches with a mean absolute deviation of 30 meV in peak positions. Beyond linear response, we simulate second harmonic generation and optical rectification in a noncentrosymmetric molecule. We foresee broad applicability of real-time propagation based on the Bethe–Salpeter equation for the study of linear and nonlinear optical properties of molecules, as the method has a computational cost similar to that of time-dependent density functional theory with hybrid functionals
Trends in expertise studies in the domain of teaching
Get PDFEducation permeates the entire society and without doubt what teachers do matters. Therefore, it is no surprise that researchers, practitioners, and policy makers share an interest in understanding outstanding performance and are eager to learn more about possibilities to support expertise development in the domain of teaching. Since the very beginning, expertise research is intrigued by the extraordinary cognitive processing of experts. In this contribution, we revisit the roots of expertise research and identify challenges when transferring this paradigm to the teaching profession. A literature review including 40 empirical studies is presented aiming at providing a historical overview and identifying trends in expertise research. Several commonalities, systematic differences and trends are apparent regarding the selection of participant groups, the role of the domain, the authenticity of setting and task, macro- and micro-level measurement, the development of tools and methods, and dynamics in research goals including merging of research paradigms. The discussion of the findings includes a plea for future directions of expertise research
Art. 8 EMRK: Sorgeentzug bei Eltern mit Behinderung - Anmerkung zum Urteil des Europäischen Gerichtshofs für Menschenrechte vom 10.6.2025 - Beschwerde-Nr. 35789/22: Á. F. L. ./. Island
No full textDas Urteil illustriert eindrücklich, wie hoch die Anforderungen an die Unterstützung von Eltern mit Behinderungen sind und wie sorgfältig ein Staat die Situation des Kindes und mögliche Alternativen im konkreten Fall überprüfen muss, bevor ein Entzug des Sorgerechts zum Schutz des Kindeswohls in Betracht kommt
The relationships between professional development, new technologies and changes at work
No full textAs technological change continues to reshape work in many sectors, there is a clear need to understand how professionals respond and develop in the face of these changes – a question that existing research has yet to fully address. This dissertation addresses this gap by answering the research question: How do different types of new technologies impact work characteristics and professional development, and how do changes in work characteristics relate to professional development and its associated work outcomes? To investigate this question, three complementary empirical studies were conducted: a systematic review of evidence in the field, an in-depth qualitative interview study in the financial sector, and a quantitative survey study in the financial sector.
Across these studies, the relationships between new technologies (i.e., task-supporting, task-replacing, and communication technologies), changes in work characteristics, aspects of professional development (i.e., elaboration, expansion, and externalisation), individual characteristics (i.e., occupational self-efficacy and technological acceptance), and key work outcomes (i.e., organisational commitment, job satisfaction, and emotional exhaustion) were systematically examined.
The first major finding is that the types of new technologies are likely to be systematically associated with distinct aspects of professional development. Task-supporting technologies were found to foster the refinement and adaptation of established routines (i.e., elaboration), while task-replacing technologies were most strongly linked to the active pursuit and acquisition of new knowledge and skills (i.e., expansion). Communication technologies, by contrast, primarily facilitated the sharing and dissemination of expertise within and between teams (i.e., externalisation). These findings suggest that the functional characteristics of different technologies play a key role in shaping how employees engage in professional development in response to technological change.
A second important contribution lies in demonstrating that new technologies change work characteristics along certain dimensions of change, including direction (i.e., increase or decrease) and intensity (i.e., the magnitude of change). The combination of qualitative and quantitative data enabled the identification of relevant work characteristics and a synthesis of changes in work characteristics into overarching themes, thereby highlighting the complex and interrelated ways in which employees experience and respond to technological developments in their workplace. These results illustrate the nuanced pathways through which the engagement in professional development is prompted by new technologies and changes at work. Additionally, the dissertation examined work outcomes related to professional development as well as individual characteristics that may affect professional development. The analyses provided limited evidence that individual characteristics may moderate the relationship between new technologies and change at work with professional development, and the relationships between professional development and work outcomes such as affective commitment were found to be complex.
The final contribution lies in the critical appraisal of the conceptual, methodological, and domain-specific choices undertaken throughout the research, underscoring both the contributions and the limitations of the current approaches. In particular, the studies highlighted the importance of using longitudinal and multi-method designs to better capture the evolving nature of work, new technologies, and learning. The exclusive focus on the financial sector also calls for future research to examine the generalisability of findings across other professional domains.
In summary, this dissertation provides empirical and conceptual groundwork for understanding the intricate interplay between new technologies, changing work characteristics, and professional development in contemporary organisations. While several open questions remain, these findings lay important groundwork for future studies and action in practice in the context of ongoing changes at work due to technological developments