In this article, Elena Russo argues that in this retelling of a popular legend, Dall’Ongaro blends the sensory experience of the Adriatic space with local legends to deepen the connection between the 19th-century Adriatic audience and the myth that he narrates.
We report the spectroscopic confirmation and fundamental properties of TOI-757 b, a mini-Neptune on a 17.5-d orbit transiting a bright star (V = 9.7 mag) discovered by the TESS mission. We acquired high-precision radial velocity measurements with the HARPS, ESPRESSO, and PFS spectrographs to confirm the planet detection and determine its mass. We also acquired space-borne transit photometry with the CHEOPS space telescope to place stronger constraints on the planet radius, supported with ground-based LCOGT photometry. WASP and KELT photometry were used to help constrain the stellar rotation period. We also determined the fundamental parameters of the host star. We find that TOI-757 b has a radius of R-p = 2.5 +/- 0.1 R-circle plus and a mass of M-p = 10.5(-2.1)(+2.2) M-circle plus, implying a bulk density of rho(p) = 3.6 +/- 0.8 g cm(-3). Our internal composition modelling was unable to constrain the composition of TOI-757 b, highlighting the importance of atmospheric observations for the system. We also find the planet to be highly eccentric with e = 0.39(-0.07)(+0.08), making it one of the very few highly eccentric planets among precisely characterized mini-Neptunes. Based on comparisons to other similar eccentric systems, we find a likely scenario for TOI-757 b's formation to be high eccentricity migration due to a distant outer companion. We additionally propose the possibility of a more intrinsic explanation for the high eccentricity due to star-star interactions during the earlier epoch of the Galactic disc formation, given the low metallicity and older age of TOI-757.
Weniger anzeigenContext. Among the thousands of exoplanets discovered to date, approximately a few hundred gas giants on short-period orbits are classified as ‘lonely’ and only a few are in a multi-planet system with a smaller companion on a close orbit. The processes that formed multi-planet systems hosting gas giants on close orbits are poorly understood, and only a few examples of this kind of system have been observed and well characterised.
Aims. Within the contest of a multi-planet system hosting a gas giant on short orbits, we characterise the TOI-1130 system by measuring masses and orbital parameters. This is a two-transiting planet system with a Jupiter-like planet (c) on a 8.35 days orbit and a Neptune-like planet (b) on an inner (4.07 days) orbit. Both planets show strong anti-correlated transit timing variations (TTVs). Furthermore, radial velocity (RV) analysis showed an additional linear trend, a possible hint of a non-transiting candidate planet on a far outer orbit.
Methods. Since 2019, extensive transit and radial velocity observations of the TOI-1130 have been acquired using TESS and various ground-based facilities. We present a new photo-dynamical analysis of all available transit and RV data, with the addition of new CHEOPS and ASTEP+ data, which achieve the best precision to date on the planetary radii and masses and on the timings of each transit.
Results. We were able to model interior structure of planet b constraining the presence of a gaseous envelope of H/He, while it was not possible to assess the possible water content. Furthermore, we analysed the resonant state of the two transiting planets, and we found that they lie just outside the resonant region. This could be the result of the tidal evolution that the system underwent. We obtained both masses of the planets with a precision of less than 1.5%, and radii with a precision of about 1% and 3% for planet b and c, respectively.
Weniger anzeigenContext. Hot Jupiters (HJs) with close-by planetary companions are rare, with only a handful of them having been discovered so far. This could be due to their suggested dynamical histories, which lead to the possible ejection of other planets. TOI-2109 b is special in this regard because it is the HJ with the closest relative separation from its host star, being separated by less than 2.3 stellar radii. Unexpectedly, transit timing measurements from recently obtained CHEOPS observations show low-amplitude transit-timing variations (TTVs).
Aims. We aim to search for signs of orbital decay and to characterise the apparent TTVs in an attempt to gain information about a possible companion.
Methods. We fitted the newly obtained CHEOPS light curves using TLCM and extracted the resulting mid-transit timings. Successively, we used these measurements in combination with TESS and archival photometric data and radial velocity (RV) data to estimate the rate of tidal orbital decay of TOI-2109 b, and also to characterise the TTVs using the N-body code TRADES and the photo-dynamical approach of PyTTV.
Results. We find tentative evidence at 3σ for orbital decay in the TOI-2109 system when we correct the mid-transit timings using the best-fitting sinusoidal model of the TTVs. We do not detect additional transits in the available photometric data, but find evidence supporting the authenticity of the apparent TTVs, indicating a close-by, outer companion with Pc > 1.125 d. Due to the fast rotation of the star, the new planetary candidate cannot be detected in the available RV measurements, and its parameters can only be loosely constrained by our joint TTV and RV modelling.
Conclusions. TOI-2109 could join a small group of rare HJ systems that host close-by planetary companions, only one of which (WASP-47 b) has an outer companion. More high-precision photometric measurements are necessary to confirm the existence of this planetary companion.
Weniger anzeigenGuardIAS is a three-year Horizon Europe project starting in January 2025, uniting diverse expertise to address aquatic invasive alien species (IAS) management. This multidisciplinary initiative comprises seven interconnected work packages targeting all invasion stages (pre-border, border, post-border) to develop tools for disrupting invasions. GuardIAS will employ Artificial Intelligence and data workflows to enhance biodiversity databases with species distributions, environmental tolerances, traits, and genetic information, thereby improving the European Alien Species Information Network (EASIN) and harmonizing key datasets. The citizen science platform iNaturalist will be enriched with expert-verified images of aquatic IAS for early detection and monitoring of geographic spread. An Early Warning System focused on IAS of EU concern will be developed and integrated into EASIN. To prevent hull biofouling-a major IAS introduction pathway-GuardIAS will explore nanotechnology-based antifouling coatings. The project will also investigate recreational boat movements along European coastlines, an understudied factor in IAS secondary dispersal. An eDNA reference library and assay panel will be developed for effective IAS detection. Advanced models, such as the Nobel Prize winning Multi-Region Input-Output analysis, will assess IAS risks, including impacts on threatened species and critical habitats under current and future scenarios. Systematic conservation planning tools will prioritize IAS monitoring and management actions based on their impacts. GuardIAS will enhance data collection, monitoring, early detection, and public awareness through innovative citizen science initiatives like BioArtBlitz events-where arts serve as a communication vehicle- eDNA sampling, sound analysis projects on Zooniverse, and marina events for boaters. Stakeholder engagement will be fostered through applied games. Collaborating with environmental authorities, industry, and aquatic managers, the project will co-design and implement eradication and control efforts in marine and freshwater environments. By integrating Social Sciences and Humanities, GuardIAS will promote collaborative knowledge creation, understand public perceptions on IAS management, and facilitate exploitation of the project's outcomes.
Weniger anzeigenWe report on the discovery of a transiting giant planet around the 3500 K M3-dwarf star TOI-6383A located 172 pc from Earth. It was detected by the Transiting Exoplanet Survey Satellite and confirmed by a combination of ground-based follow-up photometry and precise radial velocity measurements. This planet has an orbital period of ∼1.791 days, a mass of 1.040 ± 0.094MJ, and a radius of 1.008+0.036-0.033 RJ, resulting in a mean bulk density of 1.26+0.18-0.17 g cm−3. TOI-6383A has an M dwarf companion star, TOI-6383B, which has a stellar effective temperature of Teff ∼ 3100 K and a projected orbital separation of 3126 au. TOI-6383A is a low-mass dwarf star hosting a giant planet and is an intriguing object for planetary evolution studies due to its high planet-to-star mass ratio. This discovery is part of the Searching for Giant Exoplanets around M-dwarf Stars (GEMS) Survey, intending to provide robust and accurate estimates of the occurrence of GEMS and the statistics on their physical and orbital parameters. This paper presents an interesting addition to the small number of confirmed GEMS, particularly notable since its formation necessitates massive, dust-rich protoplanetary discs and high accretion efficiency (>10%).
Weniger anzeigenWe present the Andean Social–Ecological Observatory Network (ROSA, for Red de Observatorios Socioecológicos Andinos), a continent-wide monitoring initiative established to address major challenges in the management of knowledge on social–ecological systems (SES) in the Andes. The Andes, the longest mountain chain in the world, provide key ecosystem services for human wellbeing across the continent. However, the region faces multiple impacts associated with climate change and land-use change related to demographic transitions, and thus long-term monitoring is key for developing adaptation strategies to this environmental change. ROSA constitutes a bottom-up initiative to systematize and integrate social and ecological monitoring efforts into observatories, and to do so under a coproduced framework that fosters science–policy dialogue and promotes sustainable land management. The main research questions addressed by these social–ecological observatories include understanding how distant and proximate drivers of change interact with local social, cultural, economic, and environmental contexts to influence the functioning of different SES in the Andes at multiple spatial and temporal scales. We describe the origins, structure, objectives, and strategies of ROSA and key challenges faced by different monitoring networks working in the region with regard to data generation and knowledge transfer. Currently, ROSA consists of 8 nodal observatories, comprising more than 50 monitoring initiatives focused on hydroclimate, ecological, and land-use dimensions. The bottom-up structure of ROSA is founded on proven expertise in long-term data gathering and analyses and on the strong commitment of nodal monitoring groups. Effective codesign and participatory monitoring are being developed so that ROSA can contribute to knowledge coproduction for sustainable land management.
Weniger anzeigenTemperate exoplanets between the sizes of Earth and Neptune, known as "sub-Neptunes," have emerged as intriguing targets for astrobiology. It is unknown whether these planets resemble Earth-like terrestrial worlds with a habitable surface, Neptune-like giant planets with deep atmospheres and no habitable surface, or something exotic in between. Recent JWST transmission spectroscopy observations of the canonical sub-Neptune, K2-18 b, revealed ~1% CH4, ~1% CO2, and a nondetection of CO in the atmosphere. While previous studies proposed that the observed atmospheric composition could help constrain the lower atmosphere's conditions and determine the interior structure of sub-Neptunes like K2-18 b, the possible interactions between the atmosphere and a hot, supercritical water ocean at its base remain unexplored. In this work, we investigate whether a global supercritical water ocean, resembling a planetary-scale hydrothermal system, can explain these observations on K2-18 b–like sub-Neptunes through equilibrium aqueous geochemical calculations. We find that the observed atmospheric CH4/CO2 ratio implies a minimum ocean temperature of ~710 K, whereas the corresponding CO/CO2 ratio allows ocean temperatures up to ~1070 K. These results indicate that a global supercritical water ocean on K2-18 b is plausible. While life cannot survive in such an ocean, this work represents the first step toward understanding how a global supercritical water ocean may influence observable atmospheric characteristics on volatile-rich sub-Neptunes. Future observations with better-constrained CO and NH3 mixing ratios could further help distinguish between possible interior compositions of K2-18 b.
Weniger anzeigenAtmospheric nitrogen (N) deposition and anthropogenic phosphorus (P) input simultaneously affect soil respiration (RS), a crucial process that mediates soil carbon (C) cycling. However, the interaction of N deposition and anthropogenic P input on RS, as well as its components—autotrophic respiration (RA) and heterotrophic respiration (RH)—remain largely unexplored. Herein, we conducted an 8-year field experiment with N and P additions in a tropical secondary forest, integrating the vegetation traits, soil physicochemical properties, organic C fractions, and microbial properties, to explore the effects of nutrient inputs and their interactions on RS, RA, and RH. Over eight years, along P input significantly increased RS by 19.2% and RH by 42.1%. These increases were partially mitigated (by 33.2% annually for RS and 58.3% annually for RH) with the addition of N. In contrast, the co-addition of N and P enhanced RA compared to alone N or P addition, suggesting that N deposition mitigated the stimulative effect of P input on RS by reducing RH rather than RA. The structural equation model further revealed that N deposition reduced RH primarily by increasing soil N:P ratio and decreasing both the labile C fraction and fungi biomass. Our findings suggest that prevalent N deposition across low latitudes could have substantially mitigate C emissions from forest soils under anthropogenic P input.
Weniger anzeigenIn this study, we integrate experimental observations and theoretical models to elucidate the complex phenomena observed in the resonant S 𝐾-edge KLL Auger scattering spectra of the SF6 molecule. A two-dimensional spectral map, constructed of incident photon energy and kinetic energy of the emitted Auger electron, is shown to be a versatile tool for understanding a character of the core-excited potential energy surface and change of the molecular geometry. Our findings reveal how the distinct dispersion behavior of multiple spectral lines enables mapping of ultrafast dynamics within the short-lived core-excited states. Our results confirm the presence of nuclear dynamics in the S1𝑠−16𝑎1 1𝑔 and S1𝑠−16𝑡1 1𝑢 core-excited states, while dynamics is absent in the S1𝑠−17𝑡1 1𝑢 state. Using a combination of ab initio analysis, simulations with Coulomb model potentials, and a simple analytical approximation, we qualitatively demonstrate how the varying characteristics of spectral dispersion—classified as Raman, non-Raman, and anti-Raman—mirror the relative gradients of the intermediate and final states in the resonant x-ray scattering process. This insight allows for the effective mapping of molecular potential energy curves, offering a prospective tool on the underlying mechanisms of resonant Auger scattering and its potential for probing molecular dynamics.
Weniger anzeigenAntimicrobial peptides (AMPs) are essential immune effectors of multicellular organisms. Bacteria can evolve resistance to AMPs. Surprisingly, when used to challenge the yellow mealworm beetle, Tenebrio molitor, Staphylococcus aureus resistant to an abundant AMP (tenecin 1) of the very same host species did not increase host mortality or bacterial load compared to infections with wild-type S. aureus. A possible explanation is that antimicrobial resistance is costly due to the collaterally increased sensitivity of AMP-resistant strains to other immune effectors. Here, we study the sensitivity of a group of AMP-resistant S. aureus strains (resistant to tenecin 1 or a combination of tenecin 1 + 2) to other immune effectors such as phenoloxidase and other AMPs in vivo. Using RNAi-based knockdown, we investigate S. aureus survival in insect hosts lacking selected immune effectors. We find that all except one AMP-resistant strain displayed collateral sensitivity toward phenoloxidase. Some AMP-resistant strains show sensitivity to components of the yellow mealworm beetle AMP defense cocktail. Our findings are consistent with the idea that resistance to AMPs does not translate into changes in virulence because it is balanced by the collaterally increased sensitivity to other host immune effectors. AMP resistance fails to provide a net survival advantage to S. aureus in a host environment that is dominated by AMPs.
Weniger anzeigenAn ongoing controversy revolves around the detailed structure of the subducting European and Adriatic plates under the Alps and the adjacent orogens. Mostly based on P‐wave travel time tomographic images, slab break‐off at different times, reversals of subduction polarity and segmentation of the slab into independent units have been proposed. These processes may have important geodynamic consequences such as rapid surface uplift, past magmatic events or changes in the style of continental collision. However, some of the tomographic results are contradictory, particularly evident in the uppermost mantle where teleseismic P waves traverse the medium almost vertically with few ray crossings and a stronger dependence on the crustal correction. In this work, we present the result of an innovative joint inversion approach using surface‐ and teleseismic body‐wave travel times to mitigate some of the shortcomings in both data types. Applying a reversible‐jump Markov chain Monte Carlo approach, we simultaneously constrain the vP and vS structure and their uncertainties in the crust and upper mantle. The results indicate a continuous slab structure from the crust‐mantle boundary down to at least 400 km depth under the western, central and eastern Alps. The results, however, also suggest that fitting the data within their respective measurement uncertainties may not be sufficient to reliably determine the presence of a shallow slab break‐off beneath the Alps.
Weniger anzeigenCatechol-derived polymers form stable coatings on a wide range of materials including challenging to coat low surface energy polymers. Whether modification of the coating polymer with fluorophilic or hydrophobic groups is a successful approach to further favor the coating of hydrophobic or fluorophilic surfaces with catechol-based polymers remains ambiguous. Herein, we report the effect of a series of catechol-derived polyglycerol (PG)-based coatings and monolayer coatings on the wettability of polytetrafluoroethylene (PTFE), polystyrene, and poly(methyl methacrylate) surfaces. Coatings with a longer hydrophilic PG block resulted in surface coatings with water contact angles (WCAs) around 60° independently of the modification and substrate, while coatings with a longer hydrophobic anchoring block possessed more diverse WCAs up to (129 ± 10)°. Despite the generally small impact of the fluorophilic modification for most substrate/coating combinations, some fluorophilic modified coatings reduce the WCA of PTFE below Berg’s limit of 65°, indicating a shielding of fluorous segments from the surface.
Weniger anzeigenThroughout history, we have looked to nature to discover and copy pharmaceutical solutions to prevent and heal diseases. Due to the advances in metabolic engineering and the production of pharmaceutical proteins in different host cells, we have moved from mimicking nature to the delicate engineering of cells and proteins. We can now produce novel drug molecules, which are fusions of small chemical drugs and proteins. Currently we are at the brink of yet another step to venture beyond nature’s border with the use of unnatural amino acids and manufacturing without the use of living cells using cell-free systems. In this review, we summarize the progress and limitations of the last decades in the development of pharmaceutical protein development, production in cells, and cell-free systems. We also discuss possible future directions of the field.
Weniger anzeigenMucus is a complex hydrogel that acts as a defensive and protective barrier in various parts of the human body. The rise in the level of viral infections has underscored the importance of advancing research into mucus-mimicking hydrogels for the efficient design of antiviral agents. Herein, we demonstrate the gram-scale synthesis of biocompatible, lignin-based virus-binding inhibitors that reduce waste and ensure long-term availability. The lignin-based inhibitors are equipped with sulfate moieties, which are known binding partners for many viruses, including SARS-CoV-2 and herpes viruses. In addition, cross-linking the synthesized inhibitors yielded hydrogels that mimicked native mucus concerning surface functionality and rheology. The degree of sulfation exhibits a very strong impact on the mesh size distribution of the hydrogels, which provides a new means to fine-tune the steric and electrostatic contributions of the virus–hydrogel interaction. This feature strongly impacts the sequestration capability of the lignin-based hydrogels, which is demonstrated by infection inhibition assays involving human herpes simplex virus 1, influenza A viruses, and the bacterium Escherichia coli (E. coli). These measurements showed a reduction in plaque-forming units (HSV-1) and colony-forming units (E. coli) by more than 4 orders of magnitude, indicating the potent inhibition by the lignin-based hydrogels.
Weniger anzeigenSynthetic polymer hydrogels are valuable matrices for biotransformations, drug delivery, and soft implants. While the bulk properties of hydrogels depend on chemical composition and network structure, the critical role of interfacial features is often underestimated. This work presents a nanoscale modification of the gel–water interface using polymer brushes via a straightforward “grafting-to” strategy, offering an alternative to more cumbersome “grafting-from” approaches. Functional block copolymers with photoreactive anchor blocks are successfully self-assembled and UV-immobilized on hydrogel substrates despite their low solid content (<30 wt %). This versatile technique works on both bulk- and surface-immobilized hydrogels, demonstrated on poly(hydroxypropyl acrylate), poly( N -isopropylacrylamide), and alginate gels, allowing precise control over grafting density. X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry revealed a homogeneous bilayered architecture. By “brushing-up”, the hydrogels’ interface can be tailored to enhance protein adsorption, improve cell adhesion, or impair the diffusive uptake of small molecules into the bulk gels. This effective interfacial nanoengineering method is broadly applicable for enhancing hydrogel performance across a wide range of applications.
Weniger anzeigenXenotransplantation using pig organs may be associated with the transmission of porcine viruses that could cause disease in recipients. A well-known example is the porcine cytomegalovirus, which is actually a porcine roseolovirus, hence abbreviated as PCMV/PRV. This virus is related to human herpesviruses 6 and 7 and is not closely related to human cytomegalovirus, which causes significant complications in allotransplantation [1]. PCMV/PRV has been shown to drastically reduce the survival time of porcine organs in non-human primates (for review, see [2]). The virus was also transmitted to the first patient in Baltimore who received a pig heart; it replicated exponentially to high titers in the transplanted pig heart and likely contributed to the patient’s death [3]. Therefore, the transmission of PCMV/PRV and other potentially zoonotic porcine viruses should be prevented.
Weniger anzeigenTourism in Africa was entangled with colonialism from the start. However, after the Second World War it became an integral part of the colonising powers’ development agenda, albeit one that has received little scholarly attention so far. This presented African states with a serious dilemma when most of them gained independence during the 1960s. On the one hand, tourism promised to stimulate economic growth, provide much needed foreign currency, and create employment opportunities. On the other hand, international tourism had the potential to threaten the economic independence of post-colonial states and perpetuate colonial stereotypes, as well as international and local power imbalances and inequalities. The newly elected governments had to deal with this “colonial baggage.” This article focusses on the transition from colonial to post-colonial tourism in two East African countries, Kenya and Tanzania. I explore how the late colonial government pursued tourism as a development strategy for the region. I also demonstrate how Kenya and Tanzania approached tourism and its colonial legacies in different ways after independence. To trace their respective tourism histories, I draw on published reports and newspaper articles, historical research literature, in particular, from tourism scholars of various disciplines, as well as archival sources.
Weniger anzeigenUsually, duodenal barriers are investigated using intestinal cell lines like Caco-2, which in contrast to native tissue are limited in cell-type representation. Organoids can consist of all intestinal cell types and are supposed to better reflect the in vivo situation. Growing three-dimensionally, with the apical side facing the lumen, application of typical physiological techniques to analyze the barrier is difficult. Organoid-derived monolayers (ODMs) were developed to overcome this. After optimizing culturing conditions, ODMs were characterized and compared to Caco-2 and duodenal tissue. Tight junction composition and appearance were analyzed, and electrophysiological barrier properties, like paracellular and transcellular barrier function and macromolecule permeability, were evaluated. Furthermore, transcriptomic data were analyzed. ODMs had tight junction protein expression and paracellular barrier properties much more resembling the originating tissue than Caco-2. Transcellular barrier was similar between ODMs and native tissue but was increased in Caco-2. Transcriptomic data showed that Caco-2 expressed fewer solute carriers than ODMs and native tissue. In conclusion, while Caco-2 cells differ mostly in transcellular properties, ODMs reflect trans- and paracellular properties of the originating tissue. If cultured under optimized conditions, ODMs possess reproducible functionality, and the variety of different cell types makes them a suitable model for human tissue-specific investigations.
Weniger anzeigenAvian pathogenic Escherichia coli (APEC) is a principal etiologic agent of avian colibacillosis, responsible for significant economic losses in the poultry industry due to high mortality and disease treatment with antibiotics. APEC and its ability to form biofilms on food and processing surfaces contributes to its persistence within farms. Bacteriophages are promising antibacterial agents for combating APEC. This study focused on characterization of the newly isolated phages UPWr_E1, UPWr_E2, and UPWr_E4 as well as the UPWr_E124 phage cocktail containing these three phages. Methods included efficiency of plating assay, transmission electron microscopy, and characterization of their resistance to different pH values and temperatures. Moreover, phage genomes were sequenced, annotated and analyzed, and were compared with previously sequenced E. coli phages. All three phages are virulent and devoid of undesirable genes for therapy. Phage UPWr_E1 belongs to the genus Krischvirus within the order Straboviridae and both UPWr_E2 and UPWr_E4 belong to the genus Tequatrovirus within the subfamily Tevenvirinae, sharing over 95 % nucleotide identity between them. For their use on poultry farms, UPWr_E phages and the UPWr_E124 phage cocktail were tested for their anti-biofilm activity on two E. coli strains – 158B (APEC) and the strong biofilm producer NCTC 17848 – on two abiotic surfaces: a 96-well microplate, a stainless steel surface, and one biotic surface, represented by lettuce leaves. The reduction of biofilm formed by both strains in the 96-well microplate, on the stainless steel and lettuce leaf surface for bacteriophage treatment was very efficient, reducing biofilms by ranges of 50.2–83.6, 58.2–88.4 and 53–99.4 %, respectively. Therefore, we conclude that UPWr_E phages and the UPWr_E124 phage cocktail are promising candidates for APEC biocontrol.
Weniger anzeigen