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Review essay: Meyer, A. & Savoy, B. 2023. Atlas de l'absence. Le patrimoine culturel du Cameroun en Allemagne. Berlin, ed. Reimer
Get PDFBefore the publication of the book ‘Atlas de l'absence. Le patrimoine culturel du Cameroun en Allemagne’ (Meyer & Savoy 2023), no one could have imagined the sheer scale of Cameroon's cultural heritage held in public collections in Germany: some 40,000 artefacts. Faced with this immense corpus, acquired under often unequal conditions, the authors raise not only the paradoxical problem of the glaring lack of museographic documentation in Germany – scientific publications, catalogues, museum guides and systematic inventory lists – but also that of loss, amnesia or progressive memory loss in Cameroon. Between 2019 and 2023, a so-called “reverse history of collections” approach was systematised, aiming at a decolonisation of German-centred archival knowledge, coupled with research into provenance based on the relatively resilient oral traditions in Cameroon. The result is an argument that has epistemologically reconnected the collections with a sometimes chaotic set of intertemporal and intercontextual archival data, but which is vulnerable to a lack of specialisation in fundamental research on ancient African arts, considerably limiting or watering down the ethnographic counter-argument. Keywords: cultural property; translocation; public museum; Cameroon; Germany
Impact of centre volume on adrenalectomy outcomes: European multicentre study based on EUROCRINE ® registry
Get PDFBackground: The relationship between surgeon volume and patient outcomes in adrenalectomy is well established in the literature and clinical guidelines. However, evidence regarding the impact of centre volume on patient outcomes remains limited. This study aimed to evaluate the effect of centre volume on patient outcomes. Methods: This multicentre study analysed adrenalectomy procedures from the EUROCRINE® registry (2015–2024). A volume threshold was determined using receiver operating characteristic curve analysis to predict high-grade complications (Clavien–Dindo grade ≥ III). Outcomes were compared between high- and low-volume centres, and multivariable logistic regression was used to identify independent predictors of complications and death. Results: A total of 6672 patients undergoing adrenalectomy from 99 centres across Europe were included. The optimal centre volume threshold was ≥ 36 adrenalectomies per year. Only seven centres (7%) met this threshold, accounting for 36.7% of all procedures. High-volume centres had significantly lower rates of high-grade complications (0.9 versus 2.9%; P < 0.001), conversion (2.3 versus 3.5%), and reoperation (0.7 versus 1.6%), and shorter hospital stays (median 2 versus 3 days). Multivariable analysis showed high-volume centre status to be independently protective against high-grade complications (odds ratio 0.39, 95% confidence interval 0.24 to 0.63; P < 0.001), but not postoperative mortality (odds ratio 0.69; P = 0.480). Functional benign tumours compared with malignant tumours (odds ratio 0.61, 0.39 to 0.93; P = 0.020) and minimally invasive surgery (odds ratio 0.21, 0.14 to 0.31; P < 0.001) were both associated with a significantly lower risk of high-grade complications. Conclusion: Centre adrenalectomy volume is a key determinant of high-grade complication risk following adrenalectomy. A threshold of ≥ 36 adrenalectomies per year identifies high-performing centres. These findings support centralization of adrenal surgery to optimize outcomes and standardize care across institutions
The dark side of early galaxies: geko uncovers dark-matter fractions at z ∼ 4 − 6
Get PDFJames Webb Space Telescope (JWST)/NIRCam slitless spectroscopy enables dynamical mass measurements for typical star-forming galaxies only a billion years after the big bang. We model the H morpho-kinematics of 163 galaxies at redshift –6 from FRESCO and CONGRESS (with JADES imaging), using the geko code, and infer rotational velocities and dispersions within . Our sample spans –10 and –11. Gas masses are inferred from empirical scaling relations and combined with stellar masses to yield baryonic masses. The resulting median inferred gas-to-baryonic mass fraction is . Using these baryonic masses together with the dynamical masses, we derive dark-matter fractions within the H half-light radius, and find a high median value of , where is defined relative to the total (DM + baryonic) mass. About two-thirds of systems are DM-dominated within –1 kpc. We find that decreases with stellar mass, consistent with predictions from simulations. The stellar Tully–Fisher relation shows a tentative offset to higher at fixed and substantial intrinsic scatter, suggesting that the relation is only beginning to emerge at . We measure a negative correlation between and baryonic surface density , weaker but broadly consistent with trends at cosmic noon and at . Qualitatively comparing with modified NFW profiles coupled to an empirical stellar-to-halo mass relation suggests that the lowest () require cored inner DM profiles, while the highest fractions favour cuspier profiles, potentially reflecting adiabatic contraction. Overall, the elevated and at are compatible with progenitors of baryon-dominated systems at and naturally anticipate overmassive black holes at fixed
Severe and widespread coral reef damage during the 2014-2017 Global Coral Bleaching Event
Get PDFOcean warming is increasing the frequency, extent, and severity of tropical-coral bleaching and mortality. During 2014–2017, marine heatwaves caused the Third Global Coral Bleaching Event. We analyze data from 15,066 reef surveys globally during 2014–2017. Across all surveyed reefs, 80% and 35% experienced moderate or greater (affecting >10% of corals) bleaching and mortality, respectively. We assess the global extent of coral bleaching and mortality by applying bleaching response curves calibrated from surveyed reefs to predict bleaching globally, based on comprehensive remote-sensing of heat stress. These models predict that 51% and 15% of the world’s coral reefs suffered moderate or greater bleaching and mortality, respectively, during one or multiple years, surpassing damage from any prior global coral bleaching event. Our findings demonstrate that the impacts of ocean warming on coral reefs are accelerating, with the near certainty that ongoing warming will cause large-scale, possibly irreversible, degradation of these essential ecosystems. With heat stress levels during this event surpassing those observed previously, the National Oceanic and Atmospheric Administration developed more extreme Bleaching Alert levels that are now being used during the ongoing Fourth Global Coral Bleaching Event
Polyanion Chemistry Engineers Ternary RNA Nanoparticle Structure/Function from the Inside-Out
Get PDFFormulating cationic polyplexes (PP) with polyanions as ternary polyelectrolyte nanoparticles (TNP) offers a polymeric alternative to lipid nanoparticles (LNP) for targetable nucleic acid delivery. Although TNP in vivo transport is credited to their anionic surface charge, the relationships between polyanion chemistry and TNP structural stability, protein binding, and transfection are poorly understood compared to lipid-based systems. We hypothesized that carefully engineered hydrophobic polyanions could simultaneously endow TNPs with negative surface charge and enhanced extracellular stability critical to the future development of actively targeted formulations. We synthesized chemically diverse PEGylated polyanions to coat self-amplifying RNA (saRNA) PP, systematically studying how PEG architecture and polyanion chemistry modulate TNP structure and function. In both high-throughput stability assays and Small Angle Neutron Scattering structural studies, we found that PEG5k-bl-polyanion5k yields remarkably small particles with a pH-responsive core–shell structure. We identify a lead formulation (TNP5) with moderate hydrophobicity and charge density that balances extracellular stability and intracellular unpackaging for transfection. In agreement with spectroscopic characterization and in vitro cell studies, Molecular Dynamics simulations support the hypothesis that polyanions dictate TNP function from the inside-out by excluding water from the RNA core and by exposing functional groups that modulate protein binding. Our work correlates high throughput assays and detailed neutron scattering analysis to uncover mesoscale structural differences between two- and three-component polyelectrolyte delivery systems. These screening methods and the critical balances between polymer properties they uncover establish a framework for high throughput engineering of pH-responsive nanoparticle structure/function to navigate biological barriers to RNA delivery
[HP99] 159 – Properties of the first supersoft X-ray source with a helium star donor
Get PDF[HP99] 159 is remarkable as the first supersoft X-ray source (SSS) identified with an evolved helium star donor. With a likely orbital period of 1.164 d or 2.327 d, the origin of the SSS component is controversial, with the two current models being either steady He-burning on the white dwarf surface, or that it is a helium nova in the decaying phase. To help resolve this issue we present extensive new long-term spectroscopy (with SALT) and photometry (at SAAO and with OGLE) of [HP99] 159 which (a) supports 2.327 d as the orbital period, and (b) finds only a small He ii radial velocity modulation. The latter is surprising as it implies a very low inclination system, whereas our light curve modelling suggests , and hence that the He ii must be produced in outflowing material further above, or beyond, the disc. We find that the decaying nova model cannot fit our OGLE light-curve and the observed SSS flux level. [HP99] 159 has been essentially constant as an SSS over several decades, implying a sustained high level of mass-transfer from its He star donor, making it the only confirmed single-degenerate scenario SN Ia progenitor. We have updated the known SSS binary parameters and find a clear 1.5 mag difference in their when compared to the properties of LMXBs, likely due to the larger irradiated areas and more luminous donors
A deep dive into Brazilian health technology assessment: Structure, policies, and processes
Get PDFHealthcare systems worldwide face mounting pressures from aging populations, costly medical technologies, and rising healthcare expenditures. Health Technology Assessment (HTA) has emerged as a critical tool for improving efficiency and supporting evidence-informed resource allocation through systematic evaluation. In Brazil, HTA plays a central role in advancing Universal Health Coverage (UHC), particularly through the National Committee for Health Technology Incorporation (Comissão Nacional de Incorporação de Tecnologias no Sistema Único de Saúde – CONITEC). As HTA continues to evolve in Brazil, there is an increasing need for health policy and systems research to better understand its structure, challenges, and opportunities. This study aimed to comprehensively analyze the key pillars of Brazil’s national HTA system, identify existing barriers, and propose strategies to strengthen HTA processes. A mixed-methods approach was employed between 2021 and 2023, targeting HTA-related organizations and experts across multiple health sectors. Data were collected through thirteen electronic institutional surveys assessing technical aspects of HTA and nine virtual in-depth interviews exploring HTA from a policy perspective. Findings indicate a strong presence of public-sector and academic institutions within Brazil’s HTA landscape, alongside broad recognition of HTA’s value and CONITEC’s central role in coordinating evidence generation and appraisal. However, challenges such as potential conflicts of interest and reliance on exclusive government funding were identified, underscoring the need for more diversified and sustainable financing mechanisms. The system benefits from a multidisciplinary workforce and active community participation, and HTA evidence is widely used in policymaking, particularly in evaluating clinical effectiveness, costs, and economic value. Despite these strengths, limitations persist, including insufficient institutional capacity, resource constraints, and political support. Participants emphasized the need to strengthen HTA skills, competencies, and coordination to improve the effectiveness and impact of HTA processes. This study contributes to the limited literature on Brazil’s HTA system and provides evidence to inform future research and policy efforts aimed at strengthening HTA integration in support of UHC
Dataset for 'Crystal-facet-directed all vacuum deposited perovskite solar cells'
No full textThis is the complete dataset used to produce the main figures and Supplementary figures in the manuscript entitled 'Crystal-facet-directed all vacuum-deposited perovskite solar cells' published on Nature Materials. All the folders and data files are presented in the format "Figure number-figure description". The complete dataset includes raw data files, processed data files (in the form of Origin, MATLAB or Python) and raw figures
Parameter identifiability, parameter estimation and model prediction for differential equation models
No full textInterpreting data with mathematical models is an important aspect of real-world industrial and applied mathematical modeling. Often we are interested to understand the extent to which a particular set of data informs and constrains model parameters. This question is closely related to the concept of parameter identifiability, and in this article we present a series of computational exercises to introduce tools that can be used to assess parameter identifiability, estimate parameters, and generate model predictions. Taking a likelihood-based approach, we show that very similar ideas and algorithms can be used to deal with a range of different mathematical modeling frameworks. The exercises and results presented in this article are supported by a suite of open access codes that can be accessed on GitHub
Plaster casts of the portico from Aphrodisias: archaeology, politics, museology
Get PDFThis article presents a case study that demonstrates three essential uses—archaeological, political, and museological—of plaster casts in Graeco-Roman studies. The case is the Portico of Tiberius at Aphrodisias, which the Italian archaeological mission in Anatolia excavated in 1937. Casts of the architectural elements of the portico (entablature, capital, and column) were made immediately, shipped to Rome, and employed to create a one-to-one plaster reconstruction (7.5 m tall, 5.8 m wide, and 1.6 m deep) for a Fascist-period exhibition in Rome, the Mostra Augustea della Romanità. Notwithstanding its Tiberian-period inscription, there the portico was deliberately interpreted as an Augustan monument, with a clear political intent. Both the plaster fragments and the reconstruction today belong to the collection of the Museo della Civiltà Romana in Rome. These objects are extraordinary in their versatile functions—as three-dimensional documentary replicas, propagandistic tools, and a decontextualized museum exhibit—and in their capacity to represent and misrepresent their sources