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Taxing your cake and growing it too: public beliefs on the dual benefits of progressive taxation
No full textPolitical and economic elites often warn that taxes on the rich impair economic growth. Although such warnings have a long tradition in elite discourse, what the public believes about the effects of progressive taxation remains surprisingly understudied. This omission limits our understanding of a basic democratic mechanism, the congruence of elite and public opinion. To close this gap, we employ a conjoint experiment during the 2021 German national election on a representative quota sample. Participants compare policy packages that entail changes in income, inheritance, and corporate taxes and evaluate their impact on equality and growth. We find no evidence that the public believes that progressive taxes promote equality at the expense of growth. Instead, participants believe that progressive taxes are doubly beneficial, promoting both outcomes. Furthermore, such beliefs do not vary by ideology or economic status. Our findings suggest a more consensual view of progressive taxation that emphasizes positive synergies between economic growth and greater equality
PrEP public policies for HIV prevention in South America: an intersectional analysis
No full textBackground
HIV pre-exposure prophylaxis (PrEP) is a highly effective biomedical prevention strategy, recommended by the World Health Organization since 2015. However, in South America, its adoption has been uneven, reflecting structural, political, and socio-cultural inequalities. This study maps and analyzes national PrEP policies across 13 South American countries through an intersectional lens, identifying challenges and opportunities for more equitable HIV prevention strategies.
Methods
We conducted a documentary survey of national PrEP-related policies, clinical guidelines, regulations, and public communications from Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, French Guiana, Paraguay, Peru, Suriname, Uruguay, and Venezuela. Searches were performed on institutional websites in Portuguese, Spanish, English, and French using predefined keywords. In the absence of official policy documents, information was collected from media and civil society sources. Data from 118 documents were coded and analyzed using iterative summative content analysis, integrating intersectionality theory to assess how policies address (or neglect) structural inequalities.
Results
Ten countries have formal national PrEP policies (Argentina, Brazil, Chile, Colombia, Ecuador, Guyana, French Guiana, Paraguay, Peru, Uruguay), with Brazil pioneering implementation in 2017. Three countries (Bolivia, Suriname, Venezuela) lack comprehensive national guidelines. Most countries recommend daily oral PrEP; on-demand dosing is approved in fewer contexts, often with restrictions. Long-acting injectable cabotegravir has been approved only in Brazil, French Guiana, and Peru, but remains largely unavailable. Geographic coverage ranges from national to highly localized models. Prioritized groups include men who have sex with men, transgender women, sex workers, serodifferent couples, and, in some countries, people who use drugs. Policy formulation involves ministries of health, academia, international organizations, and, variably, civil society. However, inclusion of marginalized populations and integration of intersectional approaches remain limited. There are inequalities in the incorporation of social markers of difference in PrEP policies across the region, with greater emphasis on sexuality, gender, class, and health conditions, and limited attention to race/ethnicity, territory, generation, and disability.
Conclusion
PrEP policy adoption in South America demonstrates significant heterogeneity, shaped by intersecting social, political, and institutional factors. While the region has made notable advances, access remains uneven, with structural barriers such as stigma, regulatory gaps, and geographic inequities limiting impact. Incorporating intersectional perspectives into policy design and implementation is essential to ensure that PrEP – in all its modalities – is accessible as a right to health, addressing differences across multiple social, geographic, and economic dimensions
Levels and correlates of pandemic anxiety in people living with rare diseases: a cross-sectional analysis using a structural equation model
No full textBackground
Within the context of the COVID-19 pandemic and beyond, pandemic anxiety (PA) is of high social and psychopathological relevance. Compared to the general population and people living with common diseases, people living with rare diseases suffer more from the effects of a pandemic in various areas. To date, there are almost no systematic studies on PA in this subpopulation. Therefore, the current study examines the levels and factors associated with PA, as well as the relationship of PA with clinical measures of anxiety and depression disorders in people living with a wide range of different rare diseases.
Methods
Data are drawn from an online survey conducted between March 2022 and February 2023 at the Department of Medical Psychology, University Medical Center Hamburg-Eppendorf, on the care situation of people living with rare diseases during the COVID-19 pandemic. Analyses include descriptive statistics, Welch’s t-tests, linear regressions, and a multivariate mediation model tested via structural equation modeling (N=590).
Results
Compared to the general population, people living with rare diseases are more affected by PA during a pandemic. Female gender, age of 50 years and older, and living alone are risk factors for particularly high levels of PA. Furthermore, a previous COVID-19 infection is associated with lower PA; receiving vaccination correlates with higher PA. In addition to sociodemographic factors, health-related quality of life (HRQOL) and daily burden due to the rare disease are significantly associated with PA levels. Moreover, an increase in PA is associated with increased anxiety and depression scores in clinical screening questionnaires. Lastly, PA mediates the links of daily burden with anxiety and depression disorders.
Conclusions
Findings highlight specific factors that should be addressed to effectively improve the situation of people living with rare diseases in the likely event of another pandemic. In addition, it becomes apparent that PA has negative implications for mental health that can persist beyond the context of a pandemic. Hence, PA should not be trivialized as a temporary pandemic state. More research is needed to compensate for the limitations of the present study and to better understand the structure of PA in people living with rare diseases
Do it yourself: Creating 3D brain-surface models and custom-made brain matrices for guided sectioning using photogrammetry and three-dimensional printing technology
No full textBackground
Neuroethologists study many non-model animals. The development of techniques for precise and standardized histological brain analysis is key for understanding neural mechanisms across species.
New method
Here we present a novel cost-effective approach to generate species-specific brain matrices for precise and reproducible trimming, blocking, and sectioning of brain tissue. To produce the matrix, we took high-quality photographs of two male CP brains and then used the open-source 3D graphics suite Blender and its inexpensive photogrammetry plug-in SnapMesh to generate the 3D brain surface model. The brain matrix was then modeled in Blender, and 3D printed.
Results
Using this approach, we produced the first 3D brain surface model and brain matrix for Seba’s short-tailed fruit bat Carollia perspicillata, CP, and assessed its quality using CP brains. Our brain matrix facilitates and standardizes trimming or blocking of brains, providing consistent access to brain regions of CP in the sagittal and coronal planes. This workflow should be suitable for most vertebrate brains.
Comparison with existing methods
Photogrammetry offers a viable, inexpensive alternative to 3D- or CT-scanners. Our workflow is not only cheaper than alternatives, but does not require blocking the brain during preparation of the 3D surface model, resulting in no tissue loss.
Conclusion
The cost-effectiveness and the tissue-preserving features will benefit researchers globally, particularly those with limited financial means and/or few valuable specimens. By providing an accessible, customizable and reproducible workflow, our study represents a significant step toward democratizing advanced neuroscience across diverse species
Tunable Synthetic Hydrogel Modulates Hepatic Lineage Specification of Human Liver Organoid
No full textHydrogel has been widely applied in the 3D cultivation of stem cells and organoids as supporting scaffolds. However, precise engineering of cell differentiation state in 3D remains a critical challenge and demands proper design of a functionally tunable micro-niche. In this study, a tunable synthetic “click” hydrogel is presented based on dendritic polyglycerol-bicyclononyne (dPG-BCN) and poly(N-isopropylacrylamide)-co-polyethylene glycol azide (pNIPAAm-co-PEG-N3), tunable in mechanical and biochemical properties. The hydrogel is capable of hosting long-term 3D proliferation of human induced pluripotent stem cells (hiPSC) with sustained pluripotency, and induction of human liver organoid (HLO) with controlled hepatic lineage specification. Apart from mechanical regulation in HLO growth, RGD conjugation to hydrogel promotes cholangiocyte differentiation via enhanced TGF-β activation, whereas RGD-free hydrogel results in low TGF-β activation and major hepatocyte differentiation of HLO cells. In agreement with this, RGD-free hydrogel also supports the development of hepatoblast organoids (HBOs) into hepatocyte lineage. Taken together, the reported hydrogel system provides a synthetic alternative to animal-derived matrices for 3D tissue culture, offering a customizable platform for hepatic lineage specification with application potential in regenerative medicine and disease modeling
Meteorologische Messungen im Berliner Stadtgebiet mit MEVIS Stationen des Instituts für Meteorologie der Freien Universität Berlin für das Jahr 2025
No full textDer Datensatz enthält Minutenwerte der Stationen des MEVIS Messnetzes (Messwerterfassungs-, Verarbeitungs- und Informationssystem für Umweltmessdaten, welches kommerziell von der Firma Adolf Thies GmbH & Co. KG Göttingen vertrieben wird).
Das MEVIS Messnetz erhebt meteorologische Daten an Standorten, die im Berliner Stadtgebiet verteilt sind. Der Aufbau der Stationen orientiert sich am WMO Standard (Guide to Instruments and Methods of Observation, Volume I, Measurement of Meteorological Variables, WMO No. 8, http://dx.doi.org/10.25607/OBP-432) und wird vom Institut für Meteorologie der Freien Universität Berlin seit 1997 betreut.
Im Datenpaket sind die Daten des Jahres 2025 enthalten. Zu jeder der 12 Stationen gibt es eine Datei mit gepackten Daten im CSV Format und eine Stationsbeschreibung im PDF Format. Dazu gibt es eine Gesamtbeschreibung des Messnetzes als PDF Datei. Weiterführende Informationen zum MEVIS Messnetz und den Daten findet man auf der MEVIS Portalseite: https://mevis.klimod.de.The data set contains observations from the MEVIS measuring network (Measurement data acquisition, processing and information system for environmental measurement data, which is commercially distributed by the company Adolf Thies GmbH & Co. KG Göttingen) with a temporal resolution of minutes. The MEVIS measuring network collects meteorological data at locations distributed across the city of Berlin. The construction of the stations is based on the WMO standard (Guide to Instruments and Methods of Observation, Volume I, Measurement of Meteorological Variables, WMO No. 8, http://dx.doi.org/10.25607/OBP-432) and has been maintained by the Institute of Meteorology of the Freie Universität Berlin since 1997. This package contains the data from the year 2025. For each of the 12 stations there is a file with packed data in CSV format and a station description in PDF format. In addition, there is an overall description of the monitoring network in a PDF file. Further information about the MEVIS monitoring network and the data can be found at the MEVIS portal page: https://mevis.klimod.de
4-Fold Protonation of Tetracyanometalates in Superacids: Hydrogen and π-Hole Bonding in the Solid State
No full textReaction of the group 10 tetracyanometalates K2[MII(CN)4] (M = Ni, Pd, Pt) and tetracyanoaurate K[AuIII(CN)4] with an excess of the superacid HF/SbF5 results in the formation and structural characterization of homoleptic hydrogen isocyanide complexes [MII(CNH)4][SbF6]2 (M = Ni, Pd, Pt) and [AuIII(CNH)4][SbF6]3·2HF, respectively. The intermolecular interactions in the solid state are dominated by strong H···F bonded networks as well as weak contacts between the fluorine atoms and C≡N groups, which are more pronounced for the more electrophilic trication. Additionally, M···F contacts below the sum of van der Waals radii for all compounds are observed, which can be regarded as regium bonding. Furthermore, density functional theory (DFT) calculations were performed to provide an in-depth energetic and electronic characterization of the observed M···F interactions. Molecular electrostatic potential (MEP) surfaces confirm the existence of a π-hole (electrophilic region) over the metal centers, a notable transformation for these typically nucleophilic square-planar complexes of NiII, PdII, and PtII. Quantum theory of atoms in molecules (QTAIM) analysis confirms the noncovalent, closed-shell nature of the M···F contacts. Additionally, natural bond orbital (NBO) analysis quantifies the donor–acceptor character of these regium/π-hole interactions
Transkontinentaler Nationalismus in Gloria Dünklers Füchse von Llafenko und Spandau
No full textDie Masterarbeit untersucht die poetischen Werke Füchse von Llafenko und Spandau von Gloria Dünkler im Hinblick auf ihre literarische Auseinandersetzung mit transkontinentalen Formen des Nationalismus und der Erinnerungskultur im Kontext der deutsch-chilenischen Geschichte. Beide Texte thematisieren historische Verflechtungen des Nationalsozialismus mit Chile, sei es über den Einfluss nationalsozialistischer Ideologie auf die "Auslandsdeutschen" in Chile oder über die Flucht und das spätere Leben des NS-Funktionärs Walther Rauff. Während Füchse von Llafenko den migrationspolitischen Diskurs problematisiert, richtet Spandau den Fokus auf die Sichtbarmachung der scheinbaren Normalisierung nationalsozialistischer Täterbiografien im Exil und die poetische Zeugenschaft politischer Gefangener während der Pinochet-Diktatur. Die Analyse zeigt, dass sich beide Werke intertextueller und intermedialer Verfahren bedienen, etwa durch Bezüge zur "poesía testimonial" sowie durch die Einbindung von Dokumenten und Zeitungszitaten. Die lyrische Gattung ermöglicht dabei eine offene und vielschichtige Exploration der Vorstellung von „den Deutschen“ als nationaler Gruppe in Chile. Besonders in Füchse von Llafenko verschränken sich Vorstellungen eines „erfundenen Bluts“ mit Modernitätsversprechen der staatlich geförderten deutschen Migration und Selbstbildern nationaler Identität. Die wiederkehrende Metaphorik der Pflanzlichkeit eröffnet zugleich neue Denkweisen von Herkunft, Anpassung und Identitätskonstruktion jenseits territorialer Fixierungen. Im Sinne der Gedächtnistheorie nach Astrid Erll lassen sich unterschiedliche Dimensionen der Erinnerungskultur herausarbeiten: Beide konzentrieren sich auf die mentale Dimension, indem es bestehende Narrative durch dokumentarische Vertiefung hinterfragt und erweitert, während Füchse von Llafenko stärker die soziale Dimension der Erinnerungskultur adressiert, indem es den chilenischen Migrationsdiskurs literarisch reflektiert und pluralisiert. Beide Texte verdeutlichen, dass Erinnerungskultur stets von konkurrierenden Perspektiven geprägt ist
Efficient Broadband Terahertz Generation by Above-Band-Gap Excitation of the Pyroelectric ZnSnN2
No full textTerahertz (THz) radiation is a powerful probe of low-energy excitations in all phases of matter. However, it remains a challenge to find materials that efficiently generate THz radiation in a broad range of frequencies following optical excitation. Here, we investigate a pyroelectric material, ZnSnN2, and find that its above-band-gap excitation results in the efficient formation of an ultrafast photocurrent generating THz radiation. The resulting THz electric field spans a frequency range from below 1 THz to above 30 THz. The results suggest that the photocurrent is primarily driven by an ultrafast pyroelectric effect where the photo-excited carriers screen the spontaneous electric polarization of ZnSnN2. Strong structural disorder reduces the photocarrier lifetime significantly and, thus, enables broadband operation. ZnSnN2 shows a similar THz-emitter performance as the best spintronic THz emitters regarding bandwidth and amplitude. The study unveils the large potential of pyroelectric materials as efficient and broadband THz emitters with built-in bias fields