bluuebunny/crossref_metadata_2025 huggingface dataset:
Phase-resolved spectroscopic analysis of the eclipsing black hole X-ray binary M33 X-7
Authors: Ramachandran Varsha
Published: August 2024

We present a detailed spectroscopic analysis of the only known eclipsing high mass X-ray binary with a black hole companion, M33 X-7. We obtained the first UV spectra of the system accompanied by X-ray observations, taken at three key orbital phases. We performed a detailed analysis of X-Ray, UV, and archival optical spectra using stellar atmosphere models which shed light on the interaction of the stellar wind with the black hole. Our new analysis suggests a large reduction in component masses compared to previous results. Our one-dimensional calculations confirm that the photoionization by the X-ray radiation can significantly change the ionization structure and diminish the wind accelerations. For this system standard wind-fed accretion scenario alone cannot explain the observed X-ray luminosity, indicating an additional mass overflow towards the black hole. Our evolutionary models suggest that the system is transitioning towards a common envelope stage in which both components merge.
Slowly-rotating nitrogen-rich O stars in 30 Doradus
Authors: Tramper F.
Published: August 2024

The VLT/FLAMES Tarantula Survey (Evans et al. 2011) identified a group of slowly-rotating nitrogen-rich O-type stars that cannot be explained by current evolutionary models. Here we present high-quality VLT/UVES observations of four of these stars that allow a detailed quantitative spectroscopic analysis. We present the analysis of the spectra with a genetic algorithm, and discuss the future steps to be taken to further investigate the cause of the nitrogen enrichment.
Entrainment in 3D hydrodynamics simulations of neon burning
Authors: Rizzuti F. , Hirschi R. , Georgy C. , Arnett W. D. , Meakin C. , Murphy A. StJ.
Published: August 2024

Our knowledge of massive star evolution is limited by uncertainties linked with multi-dimensional processes taking place in stellar interiors. Important examples are convective boundary mixing (CBM) and entrainment, which are implemented in 1D stellar evolution models assuming simplified prescriptions. 3D hydrodynamics models can improve these prescriptions by studying realistic multi-D processes for a short timerange (minutes or hours). In these proceedings, we present results coming from a new set of high-resolution hydrodynamics simulations of a neon-burning shell in a massive star, and discuss how the entrainment law can be calibrated from 3D models and then used to improve 1D stellar evolution prescriptions.
Apsidal motion in NGC 6231: Sounding the internal structure of massive stars
Authors: Rosu S. , Rauw G. , Dupret M.-A. , Noels A. , Farnir M.
Published: August 2024

The young open cluster NGC 6231 hosts a rich population of O-type binary stars. We study several of these eccentric short-period massive eclipsing binaries and assess their fundamental parameters. The properties of these systems make them interesting targets to study tidally induced apsidal motion. The analysis of apsidal motion offers a powerful means to obtain information about the internal structure of the stars. Indeed, since the rate of apsidal motion in a binary system is proportional to the internal structure constants of the stars composing it, its value gives direct insight into the internal structure and evolutionary state of these stars. Stellar evolution models are constructed based on the observationally-determined fundamental parameters and a theoretical rate of apsidal motion is inferred. The results are striking: Adopting standard stellar evolution models yields a theoretical rate of apsidal motion much larger than the observational value. This discrepancy results from the standard models predicting too low an efficiency of internal mixing and thus too homogenous stars in terms of density. By enforcing the theoretical rates of apsidal motion to match the observational values, enhanced mixing is required, through a large overshooting parameter and/or additional turbulent/rotational mixing. Our analysis leads to the conclusion that the chemically mixed cores in those massive stars must be more extended than anticipated from standard models.
Massive star interiors revealed by gravity wave asteroseismology and high-resolution spectroscopy
Authors: Bowman Dominic M.
Published: August 2024

In recent years, it has been discovered that massive stars commonly exhibit a non-coherent form of variability in their light curves referred to as stochastic low frequency (SLF) variability. Various physical mechanisms can produce SLF variability in such stars, including stochastic gravity waves excited at the interface of convective and radiative regions, dynamic turbulence generated in the near-surface layers, and clumpy winds. Gravity waves in particular are a promising candidate for explaining SLF variability as they can be ubiquitously generated in main sequence stars owing to the presence of a convective core, and because they provide the large-scale predominantly tangential velocity field required to explain macroturbulence in spectral line fitting. Here, I provide an overview of the methods and results of studying SLF variability in massive stars from time series photometry and spectroscopy.
SPAMMS: applications and use cases for the 3D spectroscopic analysis technique to study deformed massive stars
Authors: Abdul-Masih Michael
Published: August 2024

Whether it be due to rapid rotation or binary interactions, deviations from spherical symmetry are common in massive stars. These deviations from spherical symmetry are known to cause non-uniform distributions of various parameters across the surface including temperature, which can drive internal mixing processes within the envelopes of these massive stars. Despite how common these 3D distortions are, they are often neglected in spectroscopic analyses. We present a new spectral analysis code called spamms (Spectroscopic PAtch Model for Massive Stars) specifically designed to analyze non-spherical systems. We discuss how the code works and discuss its assumptions. Furthermore, we demonstrate how spamms can be applied to a variety of different types of systems and we show how it can model 3D effects in a way that current analysis techniques are not able to.
Metallicity Dependences of Massive Star Formation from Theoretical and Observational Perspectives
Authors: Tanaka K. E. I. , Zhang Y. , Shimonishi T. , Matsukoba R.
Published: August 2024

Massive stars play crucial roles in astrophysical settings across cosmic history, and thus it is a fundamental problem to understand whether their formation processes are universal or diverse in various galactic environments. In particular, metallicity is the essential characteristic of cosmic evolution. Our theoretical studies have suggested some degrees of metallicity dependence of massive star formation. In the extremely metal-poor case of , protostellar disks are significantly unstable, and the photoionization feedback is more efficient. We also execute an ALMA survey targeting massive protostars in the Large Magellanic Clouds (LMC) with . We found that the outflow properties of LMC protostars (mass, momentum, energy) are consistent with those of Galactic protostars, suggesting the universality of massive star formation at least in the range of .
Can we detect deep axisymmetric toroidal magnetic fields in stars?
Authors: Dhouib Hachem , Mathis Stéphane , Bugnet Lisa , Van Reeth Timothy , Aerts Conny
Published: August 2024

The current angular momentum (AM) transport models fail to reproduce asterosieimic observations. One of the best candidates to explain this discrepancy is the magnetic field in radiative zones with its various possible topologies, for instance axisymmetric toroidal magnetic field. If such azimuthal field is strong enough, the Tayler’s instability could occur which induces a magnetic torque that allows a very efficient transport of AM and could trigger dynamo action in radiative layers. If such important field does not emerge at the surface, spectropolarimetry is blind. In this case, the only way to detect and characterise the field is by using magneto-asteroseismology. It consists in searching for the characteristic signatures of magnetic field in the observed frequency spectra of stellar oscillations.
Apparently isolated massive stars within Galactic Hii regions
Authors: de la Fuente Diego , Marco Amparo , Negueruela Ignacio , Patrick Lee R. , Herrero Artemio , Eikenberry Stephen S.
Published: August 2024

The Alicante Survey of MAssive Stars in Hii Regions (A-SMASHeR) is aimed at finding the ratio of massive stars that are born in isolation. We present LIRIS/WHT images and EMIR/GTC spectra of the massive stellar content in A-SMASHeR regions. Our preliminary analysis yields ∼20% of regions hosting relatively (or truly) isolated massive stars.
Contact Tracing of Massive Binary Stars
Authors: Henneco Jan , Schneider Fabian R. N. , Hekker Saskia , Laplace Eva
Published: August 2024

Stellar mergers produce more massive, rejuvenated (strongly magnetic) stars, with potentially peculiar properties, and can be detected as luminous red novae. Using a grid of detailed 1D binary evolution models, we aim to determine which binary systems are likely to merge and at what evolutionary stage. This will tell us more about the merger products, and might help us understand some of the trends found in observed single- and multiple-star populations.
Massive stars and their large-separation low-mass companions in Sco OB1
Authors: Pauwels T. , Reggiani M. , Rainot A. , Sana H.
Published: August 2024

Exploring the low-mass end of the companion mass function around massive stars is of crucial importance to constrain massive star formation theories. We present a high-contrast imaging study of 20 O- and early B-type stars in the Scorpius OB1 association. From the analysis of VLT/SPHERE data, we identify a total of 789 sources. The data probe the brown dwarf regime around massive stars, resulting in the discovery of large-separation multiple systems with mass-ratios as low as 0.001 (comparable to Jupiter-Sun mass-ratio).
Introducing the ASSESS project: Episodic Mass Loss in Evolved Massive Stars - Key to Understanding the Explosive Early Universe
Authors: Bonanos A. Z. , Maravelias G. , Yang M. , Tramper F. , de Wit S. , Zapartas M. , Antoniadis K. , Christodoulou E. , Munoz-Sanchez G.
Published: August 2024

Episodic mass loss is not understood theoretically, neither accounted for in state-of-the-art models of stellar evolution, which has far-reaching consequences for many areas of astronomy. We introduce the ERC-funded ASSESS project (2018-2024), which aims to determine whether episodic mass loss is a dominant process in the evolution of the most massive stars, by conducting the first extensive, multi-wavelength survey of evolved massive stars in the nearby Universe. It hinges on the fact that mass-losing stars form dust and are bright in the mid-infrared. We aim to derive physical parameters of ∼1000 dusty, evolved massive stars in ∼25 nearby galaxies and estimate the amount of ejected mass, which will constrain evolutionary models, and quantify the duration and frequency of episodic mass loss as a function of metallicity. The approach involves applying machine-learning algorithms to select dusty, luminous targets from existing multi-band photometry of nearby galaxies. We present the first results of the project, including the machine-learning methodology for target selection and results from our spectroscopic observations so far. The emerging trend for the ubiquity of episodic mass loss, if confirmed, will be key to understanding the explosive early Universe and will have profound consequences for low-metallicity stars, reionization, and the chemical evolution of galaxies.
The impact of binary interaction on the main-sequence morphology of young star clusters
Authors: Wang Chen , Langer Norbert , Schootemeijer Abel , Milone Antonino , Hastings Ben , Xu Xiao-Tian , Bodensteiner Julia , Sana Hugues , Castro Norberto , Lennon D. J. , Marchant Pablo , de Koter A. , de Mink Selma E.
Published: August 2024

Since massive stars form preferentially as members of close binary systems, we use dense grids of detailed binary evolution models to explore how binary evolution shapes the main-sequence morphology of young star clusters. We propose that binary mergers might be the origin of the blue main sequence stars in young star clusters. Our results imply that stars may either form by accretion, or through a binary merger, and that both paths lead to distinctly different spins, magnetic fields, and stellar mass distributions.
Numerical modeling of IR SEDs of dusty CCSN within a Bayesian framework
Authors: Zsíros Szanna , De Looze Ilse , Szalai Tamás
Published: August 2024

We investigate the physical properties of dust in the environment of three core-collapse supernovae (CCSNe) through mid-infrared (mid-IR) spectral energy distribution (SED) modeling (both analytical and numerical methods) and interpret our results within a Bayesian framework. We provide evidence that the observed late-time mid-IR excess of the SNe can be described by dust models. We conclude that in case of various types of SNe, numerical dust models with a shell-like geometry can be reconciled with analytical models, regarding the essential properties of dust grains.
Deciphering hard disks
Authors: Nazé Yaël , Rauw Gregor , Smith Myron A. , Motch Christian
Published: August 2024

Some Be stars were found to emit very bright and extremely hard thermal X-rays. This so-called γ Cas -star category is rapidly growing, showing that the phenomenon is far from being uncommon and its consequences on Be population feedback should be examined. The origin of this X-ray peculiarity is however much debated. In this contribution, we review the most recent observational clues and derive constraints on the cause of the phenomenon: properties of these stars (multiplicity status, photometric variability), X-ray reaction to disk changes, impact of stripped-star companions on the X-ray emission,…
Nitrogen production in population III stars
Authors: Tsiatsiou S. , Georgy C. , Ekström S. , Meynet G.
Published: August 2024

The first stars in the Universe have inherited their composition from primordial nucleosynthesis, so they have no metal. These stars, which are also named population III (pop III) stars, began the process of reionization in the Universe and contributed to the metal enrichment with heavy elements. Previous studies showed that they should have been rotating fast due to small or no angular momentum loss, reaching easily the critical velocity since they are massive and have very low stellar winds, thus their mass loss is very low or zero. Our aim is to study how the production of primary nitrogen is affected due to high rotation in the pop III stars. So, we compared grids of pop III stars with zero, average, and high rotation. All these models have been computed using Geneva code (GENEC) in the mass range of 9M⊙≤Mini≤ 120M⊙. Due to the rotational mixing, the carbon produced in the He-burning core is diffused towards the H-burning shell, triggering the CNO cycle and producing primary nitrogen. In some models the transition of the shell from a pp-chain H-burning to a CNO H-burning induces a strong energy release and a complete change of the stellar structure and the nucleosynthesis. The production of nitrogen is boosted for the high rotation models.
Dependence of Wolf-Rayet wind clumping on the surface temperature
Authors: Chené André-Nicolas , St-Louis Nicole , Lenoir-Craig Guillaume , Moffat Anthony F. J. , Gayley Kenneth
Published: August 2024

We present our measurements of the amplitude of photometric and spectroscopic variability due to clumping in the wind of Wolf-Rayet (WR) stars. Photometric variability was assessed using TESS light-curves, while spectroscopic variations were obtained from almost 20 years of monitoring of nearly 100 classical (presumably single) stars. Our results show an apparent dependence of the variability amplitude with the stars’ surface temperature and/or terminal velocity. Our interpretation is that it supports the idea that the dominating driver of the clumps in WR winds is a sub-surface convection region.
A search for correlations between Wolf-Rayet stochastic wind variability and stellar parameters
Authors: Lenoir-Craig Guillaume , St-Louis Nicole , Moffat Anthony F. J. , Pablo Herbert
Published: August 2024

We present the results of our analysis of 122 light-curves from 50 Wolf-Rayet (WR) stars using a red+white noise analysis, where we compare the fitted red noise features with stellar parameters to assess the presence of correlations with stellar parameters. A significant correlation between the amplitude of variability α0 and v∞ was found for the whole sample, along with several other correlations satisfying the Spearman-Rank p<0.001 criterion for both He-burning and WNh stars. Our results are compatible with several plausible processes that can have an influence on the level of variability in the winds of these stars, including a subsurface convection zone and core-generated internal gravity waves.
The Nature of Unseen Companions in Massive Single-Line Spectroscopic Binaries
Authors: Sana Hugues , Abdul-Masih Michael , Banyard Gareth , Bodensteiner Julia , Bowman Dominic M. , Dsilva Karan , Eldridge C. , Fabry Matthias , Frost Abigail J. , Hawcroft Calum , Janssens Soetkin , Mahy Laurent , Marchant Pablo , Langer Norbert , Van Reeth Timothy , Sen Koushik , Shenar Tomer
Published: August 2024

Massive stars are predominantly found in binaries and higher order multiples. While the period and eccentricity distributions of OB stars are now well established across different metallicity regimes, the determination of mass-ratios has been mostly limited to double-lined spectroscopic binaries. As a consequence, the mass-ratio distribution remains subject to significant uncertainties. Open questions include the shape and extent of the companion mass-function towards its low-mass end and the nature of undetected companions in single-lined spectroscopic binaries. In this contribution, we present the results of a large and systematic analysis of a sample of over 80 single-lined O-type spectroscopic binaries (SB1s) in the Milky Way and in the Large Magellanic Cloud (LMC). We report on the developed methodology, the constraints obtained on the nature of SB1 companions, the distribution of O star mass-ratios at LMC metallicity and the occurrence of quiescent OB+black hole binaries.
The evolution of binary-stripped stars: consequences for supernovae and black hole formation
Authors: Laplace Eva , Schneider Fabian , Podsiadlowski Philipp , de Mink Selma , Justham Stephen , Renzo Mathieu , Götberg Ylva , Farmer Rob , Vartanyan David
Published: August 2024

Gravitational-wave (GW) observations are revealing the population of compact objects from a new angle. Yet their stellar progenitors remain uncertain because few observational clues on their progenitors exist. Theoretical models typically assume that the progenitor evolution can be approximated with single-star models. We explore how binary evolution affects the pre-supernova (SN) structure of stars, and the resulting distribution of compact object remnants. We focus on the differences in the core properties of single stars and of donor stars that transfer their outer layers in binary systems and become binary-stripped. We show that the final structures of binary-stripped stars that lose their outer layers before the end of core helium burning are systematically different compared to single stars. As a result, we find that binary-stripped stars tend to explode more easily than single stars and preferentially produce neutron stars and fewer black holes, with consequences for GW progenitors.
Red Supergiants in M31: The Humphreys-Davidson limit at high metallicity
Authors: McDonald Sarah L. E. , Davies Ben , Beasor Emma R.
Published: August 2024

The empirical upper limit to Red Supergiant (RSG) luminosity, known as the Humphreys-Davidson (HD) limit, has been commonly explained as being caused by the stripping of stellar envelopes by metallicity-dependent, line-driven winds. As such, the theoretical expectation is that the HD limit should be higher at lower metallicity, where weaker mass-loss rates mean that higher initial masses are required for an envelope to be stripped. In this work, we test this prediction by measuring the luminosity function of RSGs in M31 and comparing to those in the LMC and SMC. We find that

$\[\log ({L_{{\rm{m}}ax}}/{L_ \odot }) = 5.53 \pm 0.03\]$

in M31 (Z ≳ Z⊙), consistent with the limit found for both the LMC (Z ∼ 0.5 Z⊙) and SMC (Z ∼ 0.25 Z⊙), while the RSG luminosity distributions in these 3 galaxies are consistent to within 1σ. We therefore find no evidence for a metallicity dependence on both the HD limit and the RSG luminosity function, and conclude that line-driven winds on the main sequence are not the cause of the HD limit.
The CubeSpec space mission: Asteroseismology of massive stars from time-series optical spectroscopy
Authors: Bowman D. M. , Vandenbussche B. , Sana H. , Tkachenko A. , Raskin G. , Delabie T. , Vandoren B. , Royer P. , Garcia S. , Van Reeth T. ,   the CubeSpec Collaboration
Published: August 2024

The ESA/KU Leuven CubeSpec mission is specifically designed to provide low-cost space-based high-resolution optical spectroscopy. Here we highlight the science requirements and capabilities of CubeSpec. The primary science goal is to perform pulsation mode identification from spectroscopic line profile variability and empower asteroseismology of massive stars.
The Gaia view on massive stars: EDR3 and what to expect from DR3
Authors: Maíz Apellániz Jesús , Barbá Rodolfo H. , Pantaleoni González Michelangelo , Weiler Michael , Reed B. Cameron , Fernández Aranda Román , Crespo Bellido Pablo , Sota Alfredo , Alfaro Emilio J. , Molina Lera J. Alejo
Published: August 2024

At the time of this meeting, the latest Gaia data release is EDR3, published on 3 December 2020, but the next one, DR3, will appear soon, on 13 June 2022. This contribution describes, on the one hand, Gaia EDR3 results on massive stars and young stellar clusters, placing special emphasis on how a correct treatment of the astrometric and photometric calibration yields results that are simultaneously precise and accurate. On the other hand, it gives a brief description of the exciting results we can expect from Gaia DR3.
Ultraviolet observations of massive stars and the instrumentation to come
Authors: de Castro Ana I. Gómez
Published: August 2024

The wealth of information obtained about massive stars from observations at ultraviolet (UV) wavelengths has been fundamental to understand their structure and the mechanisms regulating their evolution. There are however, important aspects that have not yet been addressed due to the lack of data and the relevant instrumentation such as the role of binarity and magnetic fields or the impact of low metallicity in the evolution of massive stars. There are plans to develop UV spectropolarimeters, UV monitors and very efficient telescopes with high collecting surfaces that will revolutionize the field. In this contribution, a short update on the current and foreseen UV instrumentation is provided.
Stellar Atmospheres and Supernovae: Systematic Errors
Authors: John Hillier D.
Published: August 2024

Over the last two decades there have been considerable advances in modelling the spectra of massive stars and supernovae (SNe). Despite this progress, there are still numerous uncertainties that affect the accuracy of models. For massive stars, convection, instabilities, clumping, and our inability to model stellar winds self-consistently likely introduce systematic errors into our analyses. For SNe, and particularly for core-collapse SNe, departures from spherical symmetry strongly affect observed spectra and need to be taken into account. There are also issues with clumping, and mixing processes (both in the progenitor and the SN explosion) that need to be resolved. For both massive stars and SNe, the accuracy and availability of atomic data continues to be an ongoing issue influencing analyses.
Observations south of HD 5980
Authors: Sixtos Andrés , Wofford Aida , Peimbert Antonio
Published: August 2024

We study the He II λ4686 emission south of multiple-star system HD 5980, which hosts two WN-type stars. We use optical VLT FORS1 long-slit spectra. The observations are close to the eclipse phase. Broad He II emission with a SNR >5 is observed as far as 7.6 pc from HD 5980. The He II emission that is closest to HD 5980 is 1.2 pc directly south and has a redshifted component with FWHM 1450 km s-1 originating in the eclipsing WN5-6 star, and a blueshifted component with FWHM 600 km s-1. The second component cannot be explained by either the nearly- eclipsed WN star or the nearby supernova remnant, SNR B0057-724. We suggest that the additional He II emission comes from the colliding winds of the two WN stars.
Epidemiology of deep vein thrombosis
Authors: Wolf Simon , Barco Stefano , Di Nisio Marcello , Mahan Charles E. , Christodoulou Konstantinos C. , ter Haar Sophie , Konstantinides Stavros , Kucher Nils , Klok Frederikus A. , Cannegieter Suzanne C. , Valerio Luca
Published: August 2024

Summary: Deep vein thrombosis (DVT) is a cause of considerable morbidity worldwide. It is a common clinical disease in the daily practice of several medical disciplines including general medicine, angiology, and internal medicine, as well as of interest to public health because of its preventability and its sensitivity to secular changes in the distribution of population risk factors. In this review we present a comprehensive overview of the epidemiological features of DVT, including incidence and risk factors. Additionally, we give an overview of the burden that DVT poses on modern health care systems.
Heterogenität als Chance in der Weiterbildung
Authors: Sartor Ivonne
Published: August 2024

Zusammenfassung: Generalistisch ausgebildete Pflegekräfte können seit April 2024 an einer pflegerischen Weiterbildung teilnehmen. Allerdings zeigt sich keine Anpassung der Weiterbildungsrichtlinie (DKG) an die generalistische Ausbildung mit Fokus auf die Vorbehaltsaufgaben im Pflegeprozess. Der Beitrag zeigt die Bedeutung von Handlungsorientierung anhand der Erwartungen von generalistisch ausgebildeten Pflegekräften in Bezug auf die Weiterbildung.
Pflegeweiterbildungen als Nullsummenspiel?
Authors: Bensch Sandra
Published: August 2024

Zusammenfassung: Pflegeweiterbildung in Deutschland ist fremdbestimmt, die Langzeitpflege unterrepräsentiert. Neue Strukturen der Pflegebildung sind nötig, von der Pflegehilfe bis zur erweiterten Pflegepraxis. Hilfreich ist eine Klassifizierung von Pflegeweiterbildungen. Hohe Qualitätsstandards in der Pflege sind notwendig, um Gesundheitsversorgung gemeinsam mit der Medizin zu gewährleisten.
Stationsalltag meistern
Authors: Gore Judy , Eichelsberger Romana , Findling Thomas , Lang Markus , Pfeilstecher Manuel , Sumerauer Isabella
Published: August 2024

Zusammenfassung: An der Fachhochschule Joanneum Graz trainieren Studierende in der Abschlusssimulation im 6. Semester komplexe pflegerische Situationen in einer interdisziplinären Simulationsklinik. Der Artikel beschreibt diese Simulation, die Vorteile simulationsbasierten Lernens, die Herausforderungen und geplante Weiterentwicklung.
Deep‐Learning Analysis of Fracture Networks Leading to System‐Size Failure in Rocks
Authors: Mathiesen Joachim , McBeck Jessica , Cordonnier Benoît , Ben‐Zion Yehuda , Renard François
Published: August 2024

Fracture networks in rocks and other geomaterials form by seismic and aseismic damage processes that could lead to system‐size failure. Here, we use a multi‐view convolutional neural network model to predict the stress proximity to macroscopic failure of experimentally deformed rock samples using two‐dimensional images. Models are trained on time series of fractures observed in rock samples through dynamic in situ synchrotron X‐ray tomography experiments. The results demonstrate that deep learning models outperform traditional estimates based on fracture density, increasing the accuracy of the predictions. Furthermore, the models provide insights into fundamental characteristics of fracture patterns that may provide precursory information on impending material failure. The trained deep learning models estimate the angle of the fracture plane relative to the principal loading direction, which is a key factor contributing to shear failure. The predicted angle of the fracture plane, in the range of 10°–30° with respect to the direction of maximum compressive stress, is consistent with the established failure criteria used in rock mechanics.
Misaligned Wind‐Waves Behind Atmospheric Cold Fronts
Authors: Sauvage César , Seo Hyodae , Barr Benjamin W. , Edson James B. , Clayson Carol Anne
Published: August 2024

Atmospheric fronts embedded in extratropical cyclones are high‐impact weather phenomena, contributing significantly to mid‐latitude winter precipitation. The three vital characteristics of the atmospheric fronts, high wind speeds, abrupt change in wind direction, and rapid translation, force the induced surface waves to be misaligned with winds exclusively behind the cold fronts. The effects of the misaligned waves under atmospheric cold fronts on air‐sea fluxes remain undocumented. Using the multi‐year in situ near‐surface observations and direct covariance flux measurements from the Pioneer Array off the coast of New England, we find that the majority of the passing cold fronts generate misaligned waves behind the cold front. Once generated, the waves remain misaligned, on average, for about 8 hr. The parameterized effect of misaligned waves in a fully coupled model significantly increases the roughness length (185%), drag coefficient (19%), and air‐sea momentum flux (11%). The increased surface drag reduces the wind speeds in the surface layer. The upward turbulent heat flux is weakly decreased by the misaligned waves because of the decrease in temperature and humidity scaling parameters being greater than the increase in friction velocity. The misaligned wave effect is not accurately represented in a commonly used wave‐based bulk flux algorithm. Yet, considering this effect in the current formulation improves the overall accuracy of parameterized momentum flux estimates. The results imply that better representing a directional wind‐wave coupling in the bulk formula of the numerical models may help improve the air‐sea interaction simulations under the passing atmospheric fronts in the mid‐latitudes.
Improved Precipitation Diurnal Cycle in GFDL Climate Models With Non‐Equilibrium Convection
Authors: Zhang Bosong , Donner Leo J. , Zhao Ming , Tan Zhihong
Published: August 2024

Most global climate models with convective parameterization have trouble in simulating the observed diurnal cycle of convection. Maximum precipitation usually happens too early during summertime, especially over land. Observational analyses indicate that deep convection over land cannot keep pace with rapid variations in convective available potential energy, which is largely controlled by boundary‐layer forcing. In this study, a new convective closure in which shallow and deep convection interact strongly, out of equilibrium, is implemented in atmosphere‐only and ocean‐atmosphere coupled models. The diurnal cycles of convection in both simulations are significantly improved with small changes to their mean states. The new closure shifts maximum precipitation over land later by about three hours. Compared to satellite observations, the diurnal phase biases are reduced by half. Shallow convection to some extent equilibrates rapid changes in the boundary layer at subdiurnal time scales. Relaxed quasi‐equilibrium for convective available potential energy holds in significant measure as a result. Future model improvement will focus on the remaining biases in the diurnal cycle, which may be further reduced by including stochastic entrainment and cold pools.
Effects of cross-linking units on the heat resistance and heat insulation properties of polysilsesquioxane-based materials
Authors: Tsutsui Kosuke , Koga Hiroyuki , Adachi Yohei , Ohshita Joji
Published: August 2024

Heat insulators are key materials for efficient energy use and reduction of CO2 emissions. Recently, we examined cross-linked polymethylsilsesquioxane (MSQ) for use as the basic structure of heat-resistant insulation materials. In this study, we prepared MSQs with different cross-linking units and examined the effects of their structures on the heat resistance and heat insulation properties. Among those, MSQ linked by diethynylbenzene had sufficiently low thermal diffusivity and moderately high heat resistance. We also showed their structure–thermal property relationships. Although other influencing factors could exist, the rigidity, π‒π interactions, and bulkiness of the cross-linking units were found to predominantly influence the thermal properties. These findings will lead to new molecular designs for polysilsesquioxane (PSQ)-based heat-resistant heat insulators with high performance.
Becoming agents for genomic change: genetic counsellors’ views of patient care and implementation influences when genomics is mainstreamed
Authors: Do Trang Thu , Martyn Melissa , McClaren Belinda , McEwen Alison , Gaff Clara
Published: August 2024

Genetic counsellors (GCs) across the world are increasingly transitioning beyond clinical genetics services to meet the growing demands for genomic healthcare. This presents a unique opportunity for GCs to be ‘genomic change agents’ as they work in alternative models of care. Through various innovative models of mainstream care funded through a change program, we explored the views of GCs regarding their position as ‘genomic change agents’ and what may hinder or drive the success of their evolving roles. Guided by the Diffusion of Innovation Theory, we conducted qualitative interviews with all twelve GCs employed by the change program in different models of providing genomics across five specialties in Australia. Audio-recordings of all interviews were transcribed verbatim and analysed using inductive content analysis. Findings show that early in these new roles, participants held varied descriptions of ‘genomics mainstreaming’: some envisioned it as an end state exclusive to medical specialists practicing genomics while others saw the involvement of GCs as crucial. Participants believed they were uniquely positioned to expedite patient access to genomic testing and counselling and enhance medical specialists’ capability to use genomics. Challenges included hesitancy of some medical specialists regarding the value of genomics in healthcare and potential tension arising from distinct perspectives and practice between genetic and non-genetic professionals. Participants anticipated a decline in the standard of care when non-genetic colleagues managed consent discussion and result disclosure. Our study underscores leadership support and peer connection with those in similar roles as essential elements for GCs’ success in mainstream settings.
Global ocean carbon uptake enhanced by rainfall
Authors: Parc Laetitia , Bellenger Hugo , Bopp Laurent , Perrot Xavier , Ho David T.
Published: August 2024

Rain alters local sea surface physical and biogeochemical properties but its spatiotemporal variability has led to its overlook in global ocean carbon uptake studies. Different physical and chemical processes in the gaseous and liquid phases control the transfer of carbon dioxide (CO2) between the atmosphere and ocean. Rain impacts the interfacial flux by (1) increasing turbulence in the ocean and (2) modulating the air–sea CO2 concentration gradient. Concurrently, raindrops inject CO2 absorbed during their fall into the ocean through wet deposition. Here this study presents a comprehensive estimate of these effects on the global ocean carbon uptake over 2008–2018 based on observational products (satellite and in situ) and reanalysis. Using various representations of the ocean surface response to rainfall and different rain products, we show that rain increases the ocean carbon sink by +0.14–0.19 PgC yr−1 over 2008–2018, representing an increase of 5–7% of the ocean carbon uptake (2.66 PgC yr−1). Rain-induced interfacial flux and wet deposition have comparable orders of magnitude. The former mainly increases the CO2 sink in the tropics because strong rain rates and weak winds induce noticeable salinity and CO2 dilution. The latter is important in the tropics, storm track regions and the Southern Ocean.
Neurospora intermedia from a traditional fermented food enables waste-to-food conversion
Authors: Maini Rekdal Vayu , Villalobos-Escobedo José Manuel , Rodriguez-Valeron Nabila , Olaizola Garcia Mikel , Prado Vásquez Diego , Rosales Alexander , Sörensen Pia M. , Baidoo Edward E. K. , Calheiros de Carvalho Ana , Riley Robert , Lipzen Anna , He Guifen , Yan Mi , Haridas Sajeet , Daum Christopher , Yoshinaga Yuko , Ng Vivian , Grigoriev Igor V. , Munk Rasmus , Wijaya Christofora Hanny , Nuraida Lilis , Damayanti Isty , Cruz-Morales Pablo , Keasling Jay. D.
Published: August 2024

Fungal fermentation of food and agricultural by-products holds promise for improving food sustainability and security. However, the molecular basis of fungal waste-to-food upcycling remains poorly understood. Here we use a multi-omics approach to characterize oncom, a fermented food traditionally produced from soymilk by-products in Java, Indonesia. Metagenomic sequencing of samples from small-scale producers in Western Java indicated that the fungus Neurospora intermedia dominates oncom. Further transcriptomic, metabolomic and phylogenomic analysis revealed that oncom-derived N. intermedia utilizes pectin and cellulose degradation during fermentation and belongs to a genetically distinct subpopulation associated with human-generated by-products. Finally, we found that N. intermedia grew on diverse by-products such as fruit and vegetable pomace and plant-based milk waste, did not encode mycotoxins, and could create foods that were positively perceived by consumers outside Indonesia. These results showcase the traditional significance and future potential of fungal fermentation for creating delicious and nutritious foods from readily available by-products.
Learning integral operators via neural integral equations
Authors: Zappala Emanuele , Fonseca Antonio Henrique de Oliveira , Caro Josue Ortega , Moberly Andrew Henry , Higley Michael James , Cardin Jessica , Dijk David van
Published: August 2024

Nonlinear operators with long-distance spatiotemporal dependencies are fundamental in modelling complex systems across sciences; yet, learning these non-local operators remains challenging in machine learning. Integral equations, which model such non-local systems, have wide-ranging applications in physics, chemistry, biology and engineering. We introduce the neural integral equation, a method for learning unknown integral operators from data using an integral equation solver. To improve scalability and model capacity, we also present the attentional neural integral equation, which replaces the integral with self-attention. Both models are grounded in the theory of second-kind integral equations, where the indeterminate appears both inside and outside the integral operator. We provide a theoretical analysis showing how self-attention can approximate integral operators under mild regularity assumptions, further deepening previously reported connections between transformers and integration, as well as deriving corresponding approximation results for integral operators. Through numerical benchmarks on synthetic and real-world data, including Lotka–Volterra, Navier–Stokes and Burgers’ equations, as well as brain dynamics and integral equations, we showcase the models’ capabilities and their ability to derive interpretable dynamics embeddings. Our experiments demonstrate that attentional neural integral equations outperform existing methods, especially for longer time intervals and higher-dimensional problems. Our work addresses a critical gap in machine learning for non-local operators and offers a powerful tool for studying unknown complex systems with long-range dependencies.
Rapid synthesis of a BODIPY derivative serving as a highly selective and sensitive fluorescence chemosensor for Hg2+ ion detection
Authors: Xu Shun-Qiang , Yang Ting-Yu , Huang Po-Tan , Yang Chi-Heng , Khantamat Orawan , Chan Leong-Perng , Li Chien-Hung
Published: August 2024

A 2-amino-1,3-propanediol-modified BODIPY was synthesized in 6 hours, exhibiting high selectivity and a fourfold emission increase with Hg2+ ions in polar solvents.
DNA circuit-based immunoassay for ultrasensitive protein pattern classification
Authors: Masurier Antoine , Sieskind Rémi , Gines Guillaume , Rondelez Yannick
Published: August 2024

Cytokines are important immune modulators, and pivotal biomarkers for the diagnostic of various diseases.
Investigating the radical properties of oxidized carbon materials under photo-irradiation: behavior of carbon radicals and their application in catalytic reactions
Authors: Ahmed Md Razu , Anaya Israel Ortiz , Nishina Yuta
Published: August 2024

Oxidized carbon materials have abundant surface functional groups and customizable properties, making them an excellent platform for generating radicals.
Ni-decorated carbon nanotubes (CNTs) derived from ethanol for electrooxidation of furan derivatives featuring H2 production
Authors: Nunthakitgoson Watinee , Chaipornchalerm Peeranat , Sohail Anousha , Thivasasith Anawat , Wattanakit Chularat
Published: August 2024

Simultaneous hydrogen production and biomass valorization are achieved using a non-precious metal-CNTs electrocatalyst (NiCNTs/NF). This cost-effective, energy-efficient method offers an alternative to traditional electrocatalysis.
Nanostructure impact on electrocatalysis in gold nanodimers via electrochemiluminescence microscopy
Authors: Tao Qian-Qian , Xu Cong-Hui , Zhao Wei , Chen Hong-Yuan , Xu Jing-Juan
Published: August 2024

An exploration of enhanced electrocatalysis mechanism of gold nanodimers via electrochemiluminescence microscopy is proposed.
New insights into coordination-cage based catalysis
Authors: Ward Michael D.
Published: August 2024

Recent work on catalysed reactions using coordination cage hosts, including new mechanistic insights and reactions types, is reviewed.
Rh(iii)-catalyzed aldehydic and aryl C–H alkylation with cyclopropanols via C–H/C–C bond activation
Authors: Dash Om Prakash , Garg Divya , Volla Chandra M. R.
Published: August 2024

Herein, we developed an efficient C–H alkylation of 2-aminobenzaldehydes and anilines employing cyclopropanol as an alkylating agent under Rh(iii)-catalysis for accessing a wide range of 1,4-diketones and β-aryl ketones in good to excellent yields.
Construction of robust Ni-based catalysts for low-temperature Sabatier reaction
Authors: Ye Runping , Wang Xuemei , Lu Zhang-Hui , Zhang Rongbin , Feng Gang
Published: August 2024

The construction of robust Ni-based catalysts for low-temperature Sabatier reaction has been reviewed in detail. The perspectives on this topic have also been provided for future catalyst design.
The multiphase structural evolution and electromagnetic properties driven by Co(iii) ions of La2−xSrxCoMnO6 (x = 0–1.0) polycrystals
Authors: Wang Xuesong , Song Hongyuan , Dong Kun , Yao Ruihang , Wu Haorong , Yang Xiaolong , Chen Liangwei , Liu Bin , Ge Zhenhua , Yu Lan
Published: August 2024

Co3+ drives the multiphase structural evolution of La2−xSrxCoMnO6, while the synergistic effect of the x = 0.6 (rhombohedra + cubic) sample gives it excellent conductivity and coercivity.
ANI neural network potentials for small molecule pKa prediction
Authors: Urquhart Ross James , van Teijlingen Alexander , Tuttle Tell
Published: August 2024

Prediction of small molecule pKa values via evaluation of thermodynamic cycles by ANI-like neural network potentials.
IPr*Thia – wingtip-flexible, sterically hindered, modular, N,C/S,C-chelating thiazole-donor N-heterocyclic carbene ligands
Authors: Podchorodecka Pamela , Dziuk Błażej , Junga Robert , Szostak Roman , Szostak Michal , Bisz Elwira
Published: August 2024

We report novel N-heterocyclic carbene (NHC) ligands with N,C/S,C-chelating thiazole donors that have been structurally and electronically characterized. These ligands show potential for coordination and catalysis studies with various metals.
Au/Ag@polyoxometalate core–shell structures: from nanoparticles to atomically precise nanoclusters
Authors: Ding Xiu-Xia , Yang Wen-Zhu , Yao Sheng-Jie , Tong Xin-Yu , Ling Yan-Xiang , Jiang Zhan-Guo , Wang Chun-Feng , Zhan Cai-Hong
Published: August 2024

Polyoxometalate-decorated Au and Ag core–shell structures offer a versatile platform. This article systematically compares the structures of nanoparticles and atomically precise nanoclusters, and outlines the prospective development of this field.
Film-forming polymer nanoparticle strategy for improving the passivation and stability of perovskite solar cells
Authors: Jia Zhenyu , Wang Ran , Zhu Lei , Altujjar Amal , Jacoutot Polina , Alkhudhari Osama M. , Mokhtar Muhamad Z. , Spencer Ben F. , Hodson Nigel W. , Wang Xuelian , Osborne-Richards Mollie , Thomas Andrew G. , Hashimoto Teruo , Faulkner Michael , Lewis David J. , Haque Saif A. , Islam M. Saiful , Saunders Jennifer M. , Saunders Brian R.
Published: August 2024

Highly deformable crosslinked polymer particles enhance perovskite solar cell passivation and stability by binding and distributing throughout the film.
19.5% Efficiency organic solar cells enabled by a direct C–H arylation-derived wide-bandgap small-molecule guest donor
Authors: Bin Hu  , Gao Shenzheng , Wang Xin , Cao Fan , Chen Yiyu , Zhang Jianqi , Bu Laju , Song Xin , Lu Guanghao
Published: August 2024

A tin-free asymmetric small-molecule guest donor (oPhFO) with a wide bandgap allows PM6:oPhFO:BTP-ec9 ternary OSCs to reach a champion efficiency of 19.5% by optimizing blend morphology and vertical phase separation as well as reducing energy loss.
Measurement of uranium in a glass matrix based on spatial confinement using fiber-optic laser-induced breakdown spectroscopy
Authors: Guo Xinyu , Wu Jian , Li Jinghui , Shi Mingxin , Zhu Xinxin , Zhou Ying , Wu Di , Song Ziyuan , Huang Sijun , Li Xingwen
Published: August 2024

The storage and management of nuclear waste materials require the detection of uranium, but traditional analytical methods are unsuitable for radioactive environments.
Lithium in Chile: present status and future outlook
Authors: Gutiérrez Gonzalo , Ruiz-León Domingo
Published: August 2024

This paper provides a comprehensive overview of the current state of lithium in Chile, with a forward-looking assessment in the context of the ongoing national lithium strategy.
A mitochondria-targeting fluorescent probe for real-time monitoring of carbon monoxide in living cells and zebrafish
Authors: Liu Qinglong , Ma Shihan , Lin Weiying
Published: August 2024

As an important cellular signaling molecule, carbon monoxide (CO) is of great significance in maintaining the physiological activities of biological systems.
Convenient synthesis of spiro-pyrazolone–pyrrolidinones via ipso-cyclization of arylidene pyrazolones with 2-chloro-N-phenylacetamides
Authors: Gond Kavyashree Kuppayya , Maddani Mahagundappa Rachappa
Published: August 2024

NaH-mediated synthesis of spiro-pyrazolone–pyrrolidinones using arylidine pyrazolones and 2-chloro-N-phenylacetamides is developed. Features are atom and step economy, mild conditions, short reaction time, gram scale reaction and good yields.
Regulation of a rutile/anatase TiO2 heterophase junction in situ grown on Ti3C2Tx MXenes with remarkable photocatalytic properties
Authors: Zheng Jiale , Cai Junhao , Li Songyuan , Li Ruoping , Huang Mingju
Published: August 2024

TiO2(rutile–anatase, R–A)/Ti3C2Tx heterophase junction (HPJ)–Schottky junction (SHJ) composites oxidized in situ by Ti3C2Tx MXenes were synthesized via a one-step hydrothermal method using Ti3C2Tx MXenes as the Ti source and water as the solvent.