bluuebunny/crossref_metadata_2025 huggingface dataset:
Non-invasive mapping of brown adipose tissue activity with magnetic resonance imaging
Authors: Cai Zimeng , Zhong Qiaoling , Feng Yanqiu , Wang Qian , Zhang Zuoman , Wei Cailv , Yin Zhinan , Liang Changhong , Liew Chong Wee , Kazak Lawrence , Cypess Aaron M. , Liu Zaiyi , Cai Kejia
Published: July 2024

Thermogenic brown adipose tissue (BAT) has a positive impact on whole-body metabolism. However, in vivo mapping of BAT activity typically relies on techniques involving ionizing radiation, such as [18F]fluorodeoxyglucose ([18F]FDG) positron emission tomography (PET) and computed tomography (CT). Here we report a noninvasive metabolic magnetic resonance imaging (MRI) approach based on creatine chemical exchange saturation transfer (Cr-CEST) contrast to assess in vivo BAT activity in rodents and humans. In male rats, a single dose of the β3-adrenoceptor agonist (CL 316,243) or norepinephrine, as well as cold exposure, triggered a robust elevation of the Cr-CEST MRI signal, which was consistent with the [18F]FDG PET and CT data and 1H nuclear magnetic resonance measurements of creatine concentration in BAT. We further show that Cr-CEST MRI detects cold-stimulated BAT activation in humans (both males and females) using a 3T clinical scanner, with data-matching results from [18F]FDG PET and CT measurements. This study establishes Cr-CEST MRI as a promising noninvasive and radiation-free approach for in vivo mapping of BAT activity.
Tofersen decreases neurofilament levels supporting the pathogenesis of the SOD1 p.D91A variant in amyotrophic lateral sclerosis patients
Authors: Weishaupt Jochen H. , Körtvélyessy Péter , Schumann Peggy , Valkadinov Ivan , Weyen Ute , Hesebeck-Brinckmann Jasper , Weishaupt Kanchi , Endres Matthias , Andersen Peter M. , Regensburger Martin , Dreger Marie , Koch Jan C. , Conrad Julian , Meyer Thomas
Published: July 2024

Background

Since the antisense oligonucleotide tofersen has recently become available for the treatment of amyotrophic lateral sclerosis (ALS) caused by mutations in SOD1, determining the causality of the over 230 SOD1 variants has become even more important. The most common SOD1 variant worldwide is p.D91A (c.272A > C), whose causality for ALS is contested when in a heterozygous state. The reason is the high allele frequency of SOD1D91A in Europe, exceeding 1% in Finno-Scandinavia.

Methods

We present the clinical disease course and serum neurofilament light chain (NfL) results of treating 11 patients either homo- or heterozygous for the SOD1D91A allele for up to 16 months with tofersen.

Results

Tofersen decreases serum neurofilament levels (sNFL), which are associated with the ALS progression rate, in the 6 ALS patients homozygous for SOD1D91A. We observe significantly lower sNfL levels in the 5 patients heterozygous for SOD1D91A. The results indicate that both mono- and bi-allelic SOD1D91A are causally relevant targets, with a possibly reduced effect size of SOD1D91Ahet.

Conclusions

The finding is relevant for decision making regarding tofersen treatment, patient counseling and inclusion of SOD1D91A patients in drug trials. As far as we are aware, the approach is conceptually new since it provides evidence for the causality of an ALS variant based on a biomarker response to gene-specific treatment.
Phenalenyl-ruthenium synergism for effectual catalytic transformations of primary amines to amides
Authors: Bandopadhyay Nilaj , Paramanik Krishnendu , Sarkar Gayetri , Roy Suvojit , Panda Subhra Jyoti , Purohit Chandra Shekhar , Biswas Bhaskar , Das Hari Sankar
Published: July 2024

Newly synthesized redox-active phenalenyl ligand-based ruthenium complexes catalyzed the selective oxidation of primary amines to amides using ambient O2.
High-throughput design of complex oxides as isothermal, redox-activated CO2 sorbents for green hydrogen generation
Authors: Cai Runxia , Yang Kunran , Wang Xijun , Rukh Mahe , Bosari Azin Saberi , Giavedoni Eric , Pierce Alexandra , Brody Leo , Tang Wentao , Westmoreland Phillip R. , Li Fanxing
Published: July 2024

A new family of Isothermal, redox-activated CO2 sorbents were successfully developed using a high-throughput combinatorial approach to facilitate the generation of green hydrogen from biogenic carbonaceous feedstocks.
Non-equilibrium plasma co-upcycling of waste plastics and CO2 for carbon-negative oleochemicals
Authors: Radhakrishnan Harish , Gnangbe Samirah , Duereh Alif , Iffat Uday Sultan Ul , A Lusi , Hu Haiyang , Hu Hui , Wright Mark Mba , Bai Xianglan
Published: July 2024

Concept of plasma co-upcycling waste plastics and CO2. CO2 serves as an oxidant and carbon source to depolymerize polyolefins into platform chemicals, whereas plastics enhance CO2 conversion. Fatty alcohols are selectively produced by adding O2.
Narrative Discourse Performance in Traumatic Brain Injury: Does Story Comprehension Predict Story Retelling?
Authors: Lê Karen , Coelho Carl , Feinn Richard
Published: July 2024

Purpose:

Little is known about the relationship between discourse comprehension and production in traumatic brain injury (TBI), especially for spoken language. This study examined to what extent narrative discourse comprehension accounts for narrative discourse production outcomes (story grammar, story completeness). A secondary aim was to provisionally test an assumption of a discourse model, the structure building framework (SBF), that discourse comprehension and production share cognitive processes by investigating the strength of the relationship between them.

Method:

Twenty-one individuals with TBI completed story comprehension and story retelling tasks. Discourse measures included the Discourse Comprehension Test, a picture story comprehension task, story grammar, and story completeness. Correlational and multiple regression analyses were performed using comprehension measures as predictors for production measures.

Results:

There were significant moderate-to-large correlations between all comprehension and production measures. Comprehension measures approached but did not reach significance for predicting story grammar performance but strongly predicted story completeness outcomes.

Conclusions:

The story comprehension measures likely tapped content aspects of discourse more so than organization. Results provided support for a link between content-focused discourse comprehension measures and discourse production outcomes, which may have clinical implications for approaches to discourse intervention. Findings were interpreted as providing preliminary support for the SBF's claim that discourse production deploys the same processes involved in discourse comprehension.

Supplemental Material:

https://doi.org/10.23641/asha.26338045
Enhancing microgrid performance with AI‐based predictive control: Establishing an intelligent distributed control system
Authors: Hasani Afshin , Heydari Hossein , Golsorkhi Mohammad Sadegh
Published: July 2024

Microgrids play a pivotal role in modern power distribution systems, necessitating precise control methodologies to tackle challenges such as performance instability, especially during islanding operations. This paper introduces an advanced control strategy that employs artificial intelligence, specifically deep neural network (DNN) predictions, to enhance microgrid performance, particularly in an islanding mode where voltage and frequency (VaF) deviations are critical concerns. By utilizing real‐time data and historical trends, the proposed controller accurately forecasts power demand and generation patterns, enabling proactive planning and optimization of efficiency, reliability, and sustainability in microgrid management. One significant aspect of this approach is to establish an intelligent distributed control system that minimizes reliance on communication devices while ensuring that VaF remains within acceptable limits. Moreover, it consolidates the roles of primary and secondary controllers within the microgrid and facilitates the prediction of load changes and load injection processes. This capability significantly reduces microgrid VaF deviations, enhancing system performance through precise power distribution and balanced coordination among distributed generators. Consequently, it ensures the stability and reliability of the system. In summary, the integration of DNN‐based predictive control represents a significant advancement in microgrid management, providing a solution to address performance challenges and optimize operational efficiency, reliability, and sustainability.
ExposureNet: Mobile camera exposure parameters autonomous control for blur effect prevention
Authors: Nahli Abdelwahed , Li Dan , Uddin Rahim , Irfan Muhammad , Oubibi Mohamed , Lu Qiyong , Zhang Jian Qiu
Published: July 2024

The quality of images we perceive visually is heavily impacted by the settings used for camera exposure. When these settings are imbalanced, it can result in an undesired prominent phenomenon known as blur effects. To address this problem, an ExposureNet project has been undertaken, which aims to develop an autonomous camera exposure settings control system for blur effects prevention. The proposed ExposureNet model is a CNN/Transformer hybrid neural structure, created and trained in a comprehensive manner to effectively predict the ideal exposure settings based on the semantic features of the scene being captured. This system is designed to learn the necessary steps for processing, such as identifying relevant scene features, using only two camera exposure parameters (shutter speed (SHS) and ISO) as training signals. As a result, this system can associate the semantic features of a scene with the appropriate exposure parameter adjustments, customized to the scene's dynamics and lighting conditions. By simultaneously optimizing all processing steps and bypassing traditional post‐processing stages, the proposed system is designed to achieve faster performance, reduced computational cost, and lower power consumption. Experimental results demonstrate that the proposed system significantly outperforms existing methods and achieves cutting‐edge performance.
Identification and analysis of epithelial‐mesenchymal transition‐related key long non‐coding RNAs in hypospadias
Authors: Gao Hongjie , Ding Chen , Chang Mengmeng , Lu Zhiyi , Li Ding , Bi Dan , Sun Fengyin
Published: July 2024

EMT dysfunction is a dominant mechanisms of hypospadias. Thus, identification of EMT‐related lncRNAs based on transcriptome sequencing data of hypospadias might provide novel molecular markers and therapeutic targets for hypospadias. First, the microarray data related to hypospadias were downloaded from Gene Expression Omnibus (GEO). Besides, the differentially expressed lncRNAs and messenger RNAs (mRNAs) related to EMT were screened to construct lncRNA‐mRNA co‐expression interaction pairs. In addition, the microRNA (miRNA) prediction analysis was performed through bioinformatics methods to construct a ceRNA network. Moreover, function prediction and function enrichment and pathway analyses were also performed. Finally, the core EMT‐related lncRNAs were verified based on mRNA expression changes and cell functions. A total of 6 EMT‐related lncRNAs were identified and 123 mRNA‐lncRNA co‐expression interaction pairs were screened in this study. Additionally, a ceRNA regulatory network comprising 17 mRNAs, 4 lncRNAs, and 28 miRNAs was constructed based on the prediction of hypospadias‐related miRNAs. The validation results of the dataset GSE121712 revealed that only BEX1 was positively correlated with the expression of the lncRNA GNAS‐AS1 (r = 0.874, P < 0.01), both of which had high expression. The cell experiment results demonstrated that interfering with the expression of GNAS‐AS1 significantly promoted the proliferation, migration, and EMT of cells. Importantly, it was confirmed that GNAS‐AS1 can serve as a ceRNA and play an important role in the EMT of hypospadias. Hence, it may be considered as a potential target in the treatment of this disease.
X-Shooting ULLYSES: Massive stars at low metallicity
Authors: Ramachandran V. , Sander A. A. C. , Pauli D. , Klencki J. , Backs F. , Tramper F. , Bernini-Peron M. , Crowther P. , Hamann W.-R. , Ignace R. , Kuiper R. , Oey M. S. , Oskinova L. M. , Shenar T. , Todt H. , Vink J. S. , Wang L. , Wofford A. ,   the XShootU Collaboration
Published: July 2024

On the route toward merging neutron stars and stripped-envelope supernovae, binary population synthesis predicts a large number of post-interaction systems with massive stars that have been stripped of their outer layers. However, observations of such stars in the intermediate-mass regime below the Wolf-Rayet masses are rare. Using X-Shooting ULLYSES (XShootU) data, we have discovered three partially stripped star + Be/Oe binaries in the Magellanic Clouds. We analyzed the UV and optical spectra using the Potsdam Wolf-Rayet (PoWR) model atmosphere code by superimposing model spectra that correspond to each component. The estimated current masses of the partially stripped stars fall within the intermediate-mass range of ≈4 − 8 M⊙. These objects are found to be over-luminous for their corresponding stellar masses, which aligns with the luminosities during core He-burning. Their accompanying Be/Oe secondaries are found to have much higher masses than their stripped primaries (mass ratio ≳2). The surfaces of all three partially stripped stars exhibit clear indications of significant nitrogen enrichment as well as a depletion of carbon and oxygen. Furthermore, one of our sample stars shows signs of substantial helium enrichment. Our study provides the first comprehensive determination of the wind parameters of partially stripped stars in the intermediate-mass range. The wind mass-loss rates of these stars are estimated to be on the order of 10−7 M⊙ yr−1, which is more than ten times higher than that of OB stars with the same luminosity. The current mass-loss recipes commonly employed in evolutionary models to characterize this phase are based on OB or WR mass-loss rates, and they significantly underestimate or overestimate the observed mass-loss rates of (partially) stripped stars by an order of magnitude. Binary evolution models suggest that the observed primaries had initial masses in the range of 12−17 M⊙, and are potential candidates for stripped-envelope supernovae resulting in the formation of a neutron star. If these systems survive the explosion, they will likely evolve to become Be X-ray binaries and later double neutron stars.
Revisiting thermoelectric effects in the crust of neutron stars
Authors: Gakis Dionysios , Gourgouliatos Konstantinos N.
Published: July 2024

Context. Large thermal variations have been observed in neutron stars that typically are not aligned with density gradients. Such terms may activate the Biermann battery effect, leading to thermoelectric interactions and to the generation of electromotive force.

Aims. We aim to identify the possible impact of a temperature anisotropy on the crust of a neutron star can have in the evolution of its magnetic field, through the thermoelectric terms.

Methods. We considered a neutron star crust with large temperature gradients, associated with long-lived hot spots, described by a localized Gaussian-type function. We simulated the interplay between the battery term and the Hall and Ohmic evolution numerically for axisymmetric systems.

Results. The results indicate that for crust temperatures of ∼109 K the toroidal field can be amplified up to ∼1014 − 1015 G near the points of maximum temperature gradients, and it locally changes the architecture of the poloidal field lines. For internal crustal temperatures of ∼108 K, the temperature gradient generates fields that are lower by about two orders of magnitude. In these cases, saturation is achieved after some hundred thousand years, after which the battery and Ohmic dissipation balance each other, whereas the Hall drift contributes comparatively little to the final field strength, but it can affect its structure.

Conclusions. We conclude that the thermoelectric effect can impact the overall magnetic field evolution, provided that the thermal gradient is maintained for a sufficiently long time. Neutron stars endowned with moderate-strength magnetic fields may be affected by the thermoelectric effect if the hotspots survive for timescales of a few kiloyears.
Characterising the stellar differential rotation based on largest-spot statistics from ground-based photometry
Authors: Tuomi Mikko , Lehtinen Jyri J. , Henry Gregory W. , Hackman Thomas
Published: July 2024

Aims. Stellar spot distribution has consequences on the observable periodic signals in long-time baseline ground-based photometry. We model the statistics of the dominating spots of two young and active Solar-type stars, V889 Her and LQ Hya, in order to obtain information on the underlying spot distribution, rotation of the star, as well as the orientation of the stellar axis of spin.

Methods. By calculating estimates for spot-induced periodicities in independent subsets of photometric data, we obtain statistics based on the dominating spots in each subset, giving rise to largest-spot statistics accounting for stellar geometry and rotation, including differential rotation.

Results. Our simple statistical models are able to reproduce the observed distribution of photometric signals rather well. This also enables us to estimate the dependence of angular velocity of the spots as a function of latitude. Our results indicate that V889 Her has a non-monotonic differential rotation curve with a maximum angular velocity between latitudes of 37–40 deg and lower angular velocity at the pole than the equator. Our results for LQ Hya indicate that the star rotates much like a rigid body. Furthermore, the results imply that the monotonic Solar differential rotation curve may not be a universal model for other solar-type stars.

Conclusions. The non-monotonicity of the differential rotation of V889 Her is commonly produced in magnetohydrodynamic simulations, which indicates that our results are realistic from a theoretical perspective.
The neutral gas phase nearest to supermassive black holes
Authors: Thi W.-F. , Papadopoulos P. P.
Published: July 2024

Context. Broad line regions (BLRs) are known to contain gravitationally bound gas within a r∼(few) × (102 − 103) Schwarszchild radii (RS) near supermassive black holes (SMBHs) in active galactic nuclei (AGNs). Photo-ionized by a strong non-stellar AGN continuum, this gas emits luminous ultraviolet/optical/near-infrared lines from ionized hydrogen (and other multi-ionized atoms) that have the widest velocity profiles observed in galaxies, uniquely indicating the deep gravitational wells of SMBHs.

Aims. Nearly all BLR studies focus on its ionized gas phase (hereafter BLR+), with typical masses of only ∼(few) × (10–100) M⊙, despite strong indications of neutral BLR gas reservoirs (hereafter, BLR0) with MBLR0 ∼ 105−6 M⊙.

Methods. We used the photoionization code CLOUDY, with its chemistry augmented using three-body reactions, to explore 1D models of dustless BLRs, focusing on the BLR0 conditions and the abundances of its most prevalent neutral atoms and molecules.

Results. A (neutral-atom-) and molecule-rich BLR0 gas phase is found to be underlying the BLR+. The latter occupies only a thin outer layer of AGN-irradiated gas column densities, while the former contains the bulk of the BLR gas mass. Atomic carbon and oxygen as well as the CO molecule can reach substantial abundances in the BLR0, while their lines at infrared (IR) and submillimeter (submm) wavelengths can yield new probes of the BLR physical conditions and dynamics, unhindered by the dust absorption from outer AGN tori that readily absorb the BLR+ optical and far-ultraviolet (FUV) lines.

Conclusions. We find that neutral-atom-rich and even molecule-rich gas can exist in the BLR0. The corresponding spectral lines from neutral atoms and molecules promise a new spectral window of gas dynamics in the vicinity of SMBHs unhindered by dust absorption. This may even offer the prospect of conducting novel tests of general relativity in strongly curved spacetime.
Revisiting the dynamical masses of the transiting planets in the young AU Mic system: Potential AU Mic b inflation at ~20 Myr
Authors: Mallorquín M. , Béjar V. J. S. , Lodieu N. , Zapatero Osorio M. R. , Yu H. , Suárez Mascareño A. , Damasso M. , Sanz-Forcada J. , Ribas I. , Reiners A. , Quirrenbach A. , Amado P. J. , Caballero J. A. , Aigrain S. , Barragán O. , Dreizler S. , Fernández-Martín A. , Goffo E. , Henning Th. , Kaminski A. , Klein B. , Luque R. , Montes D. , Morales J. C. , Nagel E. , Pallé E. , Reffert S. , Schlecker M. , Schweitzer A.
Published: July 2024

Context. Understanding planet formation is important in the context of the origin of planetary systems in general and of the Solar System in particular, as well as to predict the likelihood of finding Jupiter, Neptune, and Earth analogues around other stars.

Aims. We aim to precisely determine the radii and dynamical masses of transiting planets orbiting the young M star AU Mic using public photometric and spectroscopic datasets.

Methods. We performed a joint fit analysis of the TESS and CHEOPS light curves and more than 400 high-resolution spectra collected with several telescopes and instruments. We characterise the stellar activity and physical properties (radius, mass, density) of the transiting planets in the young AU Mic system through joint transit and radial velocity fits with Gaussian processes.

Results. We determine a radius of Rpb = 4.79 ± 0.29 R⊕, a mass of Mpb = 9.0 ± 2.7 M⊕, and a bulk density of ρpb = 0.49 ± 0.16 g cm−3 for the innermost transiting planet AU Mic b. For the second known transiting planet, AU Mic c, we infer a radius of Rpc = 2.79 ± 0.18 R⊕, a mass of Mpc = 14.5 ± 3.4 M⊕, and a bulk density of ρpc = 3.90 ± 1.17 g cm−3. According to theoretical models, AU Mic b may harbour an H2 envelope larger than 5% by mass, with a fraction of rock and a fraction of water. AU Mic c could be made of rock and/or water and may have an H2 atmosphere comprising at most 5% of its mass. AU Mic b has retained most of its atmosphere but might lose it over tens of millions of years due to the strong stellar radiation, while AU Mic c likely suffers much less photo-evaporation because it lies at a larger separation from its host. Using all the datasets in hand, we determine a 3σ upper mass limit of Mp[d] sin i = 8.6 M⊕ for the AU Mic’d’ TTV-candidate. In addition, we do not confirm the recently proposed existence of the planet candidate AU Mic ’e’ with an orbital period of 33.4 days. We investigated the level of the radial velocity variations and show that it is lower at longer wavelength with smaller changes from one observational campaign to another.
Scaling up global kinetic models of pulsar magnetospheres using a hybrid force-free-PIC numerical approach
Authors: Soudais Adrien , Cerutti Benoît , Contopoulos Ioannis
Published: July 2024

Context. The particle-in-cell approach has proven effective in modeling neutron-star and black-hole magnetospheres from first principles, but global simulations are plagued with an unrealistically small separation between the scales where microphysics operates and the system-size scales due to limited numerical resources. A legitimate concern is whether the scale separation achieved to date is large enough for results to be safely extrapolated to realistic scales.

Aims. In this work, our aim is to explore the effect of scaling up physical parameters and to check whether salient features uncovered by pure kinetic models at smaller scales are still valid, with a special emphasis on particle acceleration and high-energy radiation emitted beyond the light cylinder.

Methods. To reach this objective, we developed a new hybrid numerical scheme coupling the ideal force-free and the particle-in-cell methods to optimize the numerical cost of global models. We propose a domain decomposition of the magnetosphere based on the magnetic-field topology using the flux function. The force-free model is enforced along open field lines while the particle-in-cell model is restricted to the reconnecting field line region.

Results. As a proof of concept, this new hybrid model is applied to simulate a weak millisecond pulsar magnetosphere with realistic scales using high-resolution axisymmetric simulations. Magnetospheric features reported by previous kinetic models are recovered, and strong synchrotron radiation above 100MeV consistent with the Fermi-LAT gamma-ray pulsar population is successfully reproduced.

Conclusions.This work further consolidates the shining-reconnecting current sheet scenario as the origin of the gamma-ray emission in pulsars, as well as firmly establishing pulsar magnetospheres as at least teraelectronvolt particle accelerators.
Detection of the [C I] λ8727 emission line
Authors: Akras S. , Monteiro H. , Walsh J. R. , Konstantinou L. , Gonçalves D. R. , Garcia–Rojas J. , Boumis P. , Aleman I.
Published: July 2024

We report the first spatially resolved detection of the near-infrared [C I] λ8727 emission from the outer pair of low-ionization structures in the planetary nebula NGC 7009 from data obtained by the Multi Unit Spectroscopic Explorer integral field unit. This atomic carbon emission marks the transition zone between ionized and neutral gas and for the first time offers direct evidence that LISs are photodominated regions. The outer LIS pair exhibits intense [C I] λ8727 emission, but He I λ8733 is absent. Conversely, the inner pair of knots shows both lines, likely due to the host nebula emission. Furthermore, the [C I] λ8727 line is absent in the host nebula emission, but He I λ8733 is present. Although the origin of the [C I] λ8727 line is still debated, its detection supports the scenario of photoevaporated dense molecular clumps.
Source regions of carbonaceous meteorites and near-Earth objects
Authors: Brož M. , Vernazza P. , Marsset M. , Binzel R. P. , DeMeo F. , Birlan M. , Colas F. , Anghel S. , Bouley S. , Blanpain C. , Gattacceca J. , Jeanne S. , Jorda L. , Lecubin J. , Malgoyre A. , Steinhausser A. , Vaubaillon J. , Zanda B.
Published: July 2024

Context. The source regions of ordinary chondrites (~80% of all falls) and large S-type near-Earth objects (NEOs; ~30%) have recently been identified with three young asteroid families (Karin, Koronis, Massalia) being at the origin of most ordinary chondrite falls.

Aims. The present work is a continuation of our previous studies and aims to determine the source regions of the remaining meteorite and NEO classes, with an emphasis on carbonaceous chondrites (CM, CI, CO, CV, CK, CR, CH, CB, or C-ungrouped).

Methods. We studied 38 individual asteroid families, including young and old ones, and determined their contributions to the NEO populations at metre and kilometre sizes using collisional and orbital models. Our models are in agreement with spectroscopic observations of NEOs, cosmic-ray exposure ages of meteorites, statistics of bolides, infrared emission from dust bands, composition of interplanetary dust particles (IDPs), and abundance of extraterrestrial helium-3.

Results. We identified the Veritas, Polana, and Eos families as the primary sources of CM/CR, CI, and CO/CV/CK chondrites, respectively. Substantial contributions are also expected from CM-like König and CI-like Clarissa, Misa, and Hoffmeister families. The source regions of kilometre-sized bodies are generally different. The Adeona family is by far the main source of CM-like NEOs, whereas the Polana (low-i) and Euphrosyne (high-i) families are at the origin of most CI-like NEOs. The Polana family is the likely source of both Ryugu and Bennu. We were able to link spectroscopically and dynamically several NEOs to the Baptistina family. Finally, it appears that the pre-atmospheric flux of carbonaceous chondrites at metre sizes is about the same as that of ordinary chondrites. Given the difference in fall statistics between the two groups (80% versus 4.4%), this implies either substantial atmospheric fragmentation of carbonaceous bodies at the level of ~0.5 MPa or destruction by thermal cracking and water desorption.

Conclusions. The source regions of most meteorites and kilometre-sized NEOs have now been determined, including some minor classes such as enstatite chondrites and achondrites (Nysa, Hungaria), acapulcoites and lodranites (Iannini). Future work should focus on the few remaining classes (essentially, iron meteorites, pallasites, and ureilites).
Investigating the interplay between the coronal properties and the hard X-ray variability of active galactic nuclei with NuSTAR
Authors: Serafinelli Roberto , De Rosa Alessandra , Tortosa Alessia , Stella Luigi , Vagnetti Fausto , Bianchi Stefano , Ricci Claudio , Kammoun Elias , Petrucci Pierre-Olivier , Middei Riccardo , Lanzuisi Giorgio , Marinucci Andrea , Ursini Francesco , Matt Giorgio
Published: July 2024

Active galactic nuclei (AGN) are extremely variable in the X-ray band down to very short timescales. However, the driver behind the X-ray variability is still poorly understood. Previous results suggest that the hot corona responsible for the primary Comptonized emission observed in AGN is expected to play an important role in driving the X-ray variability. In this work, we investigate the connection between the X-ray amplitude variability and the coronal physical parameters; namely, the temperature (kT) and optical depth (τ). We present the spectral and timing analysis of 46 NuSTAR observations corresponding to a sample of 20 AGN. For each source, we derived the coronal temperature and optical depth through X-ray spectroscopy and computed the normalized excess variance for different energy bands on a timescale of 10 ks. We find a strong inverse correlation between kT and τ, with correlation coefficient of r < −0.9 and negligible null probability. No clear dependence was found among the temperature and physical properties, such as the black hole mass or the Eddington ratio. We also see that the observed X-ray variability is not correlated with either the coronal temperature or optical depth under the thermal equilibrium assumption, whereas it is anticorrelated with the black hole mass. These results can be interpreted through a scenario where the observed X-ray variability could primarily be driven by variations in the coronal physical properties on a timescale of less than 10 ks; whereas we assume thermal equilibrium on such timescales in this work, given the capability of the currently available hard X-ray telescopes. Alternatively, it is also possible that the X-ray variability is mostly driven by the absolute size of the corona, which depends on the supermassive black hole mass, rather than resulting from any of its physical properties.
Exploring Galactic open clusters with Gaia
Authors: Alfonso Jeison , García-Varela Alejandro , Vieira Katherine
Published: July 2024

Context. Since the first publication of the Gαία catalogue, a new view of our Galaxy has arrived. Its astrometric and photometric information has improved the precision of the physical parameters of open star clusters obtained from them.

Aims. Using the Gaia Data Release 3 (DR3) catalogue, our aim was to find physical stellar members including faint stars for 370 Galactic open clusters located within 1 kpc. We also estimated the age, metallicity, distance modulus, and extinction of these clusters.

Methods. We employed the HDBSCAN algorithm on both astrometric and photometric data to identify members in the open clusters. Subsequently, we refined the samples by eliminating outliers through the application of the Mahalanobis metric utilizing the χ2 distribution at a confidence level of 95%. Furthermore, we characterized the stellar parameters with the PARSEC isochrones.

Results. We obtained reliable star members for 370 open clusters with an average parallax error of σϖ = 0.16 mas. We identified about ~40% more stars in these clusters compared to previous work using the Gaia DR2 catalogue, including faint stars as new members with G ≥ 17. Before the clustering application we corrected the parallax zero-point bias to avoid spatial distribution stretching that may affect clustering results. Our membership lists include merging stars identified by HDBSCAN with astrometry and photometry. We note that the use of photometry in clustering can recover up to 10% more stars in the fainter limit than clustering based on astrometry only; this combined with the selection of stars filtered out by quality cuts significantly reduces the number of stars with huge σϖ. After clustering, we estimated age, Z, and AV from the photometry of the membership lists.

Conclusions. We carried out a search to extend the membership list for 370 open clusters mainly on the Galactic plane in a neighbourhood of 1 kpc. Our methodology provides a robust estimator for the identification of outliers and also extends the membership lists to fainter stars in most of the clusters. Our findings suggest the need to carefully identify spurious sources that may affect clustering results.
Imprint of the magnetic activity cycle on solar asteroseismic characterisation based on 26 years of GOLF and BiSON data
Authors: Bétrisey J. , Farnir M. , Breton S. N. , García R. A. , Broomhall A.-M. , Amarsi A. M. , Kochukhov O.
Published: July 2024

Context. Asteroseismic modelling will play a key role in future space-based missions, such as PLATO, CubeSpec, and Roman. Despite remarkable achievements, asteroseismology has revealed significant discrepancies between observations and theoretical predictions of the physics used in stellar models, which have the potential to bias stellar characterisation at the precision level demanded by PLATO. The current modelling strategies largely overlook magnetic activity, assuming that its effects are masked within the parametrisation of the so-called ‘surface effects’. Given the presence of activity cycles in multiple solar-like oscillators and activity variations in a significant fraction of Kepler observations of main-sequence stars, it is therefore relevant to investigate systematic errors in asteroseismic characterisations caused by our incomplete understanding of magnetic activity.

Aims. Based on 26.5 years of GOLF and BiSON observations, we measured the impact of magnetic activity on the asteroseismic characterisation of the Sun as a star, a reference target for assessing the PLATO mission requirements.

Methods. The GOLF and BiSON observations, which fully cover solar cycles 23 and 24, were divided into yearly overlapping snapshots, each delayed by a quarter of a year. For each snapshot, an advanced asteroseismic characterisation, similar to that to be adopted by the PLATO pipeline, was performed with standard prescriptions for the parametrisation of the surface effects. This allowed us to monitor the apparent temporal evolution of fundamental solar parameters such as mass, radius, and age. The correlation of these parameters with the 10.7 cm radio emission flux, a proxy of the solar activity cycle, was then measured.

Results. The effects of magnetic activity are partially absorbed into the parametrisation of the surface effects when suitable prescriptions are used, and they do not significantly affect the measured solar mass or radius. However, contrary to literature expectations, we find a significant imprint on the age determination, with variations of up to 6.5% between solar minima and maxima. This imprint persists across both BiSON and GOLF datasets.

Conclusions. Considering that the Sun exhibits low levels of activity, our study highlights the looming challenge posed by magnetic activity for future photometry missions, and it prompts a potential reevaluation of the asteroseismic characterisation of the most active Kepler targets.
Les risques de cryptosporidiose chez les veaux laitiers sous nourrice
Authors: Constancis Caroline , Bernard Marion , Chartier Christophe , Ravinet Nadine
Published: July 2024

La conduite des veaux laitiers avec des vaches nourrices consiste à allaiter des veaux laitiers mâles et femelles par une vache laitière non traite. Cette pratique, développée sur le terrain par les éleveurs, tend à se répandre en France, notamment en agriculture biologique, mais elle reste mal documentée en ce qui concerne les impacts sur la santé des veaux, notamment vis-à-vis de la cryptosporidiose.

L'objectif de cette étude est d'évaluer l'excrétion fécale des ookystes de Cryptosporidium spp. par ces veaux et d'identifier les facteurs de risque d'excrétion liés à cette pratique d’élevage innovante.

Entre janvier et mai 2019, les pratiques d'élevage des veaux avec des vaches nourrices ont été décrites dans 18 fermes et 401 veaux ont été prélevés entre 4 et 21 jours pour quantifier l'excrétion fécale d'ookystes de Cryptosporidium spp.

Cette conduite innovante comporte généralement une première phase avec la mère, puis une phase optionnelle d'alimentation au lait donné par l’éleveur, et une phase d'adoption à proprement parler par une vache nourrice.

En moyenne, chaque vache nourrice a élevé 3 veaux d'âge proche avec un âge médian d'adoption de 4 jours.

La prévalence d'excrétion d'ookystes a été de 41,9 p. cent et le score d’excrétion noté de 0 à 4 était faible (0,7 en moyenne).

Le risque d'excrétion augmente lorsque le veau nait en fin de saison de vêlage (vs début de saison), ou lorsque le veau est avec sa mère en bâtiment (vs au pâturage).

Le risque d'excrétion est également plus élevé pour un veau adopté avant l'âge de 4 jours (vs après 4 j) ou pour un veau adopté avec un autre veau qui excrète des ookystes (vs pas de congénère excréteur). La fin de la saison de vêlage et le vêlage en bâtiment ont été confirmés comme des facteurs de risque déjà identifiés en élevage bovin.

L'adoption précoce et la présence d'un veau infecté dans le groupe d'adoption sont de nouveaux facteurs de risque en lien avec ces pratiques d'élevage de veaux innovantes.
Conduite à tenir face à des mortalités subites en élevage caprin
Authors: Vialard Jaquemine
Published: July 2024

Bien souvent, le diagnostic de mort brutale chez les caprins est établi sur une base de probabilité (entérotoxémie chez les adultes, septicémie colibacillaire chez les chevreaux). En réalité, de nombreuses maladies infectieuses (Pasteurellose, Mycoplasmose, Mammite staphylococcique, …) mais également parasitaires (Hæmonchose, Coccidiose, …) peuvent être responsables de morts brutales chez les caprins.

Les causes nutritionnelles (acidose, alcalose) ou les intoxications (végétales ou chimiques) ne sont pas rares.

L'abord de ce type de situation doit se faire faire avec méthode et rigueur, malgré un contexte stressant à la fois pour l'éleveur et pour le praticien.

Le recueil des commémoratifs sur les événements particuliers qui ont pu se produire dans les jours qui ont précédé (changements alimentaires ou de pâturage, travaux dans l'environnement des animaux, …) ainsi que la réalisation systématique d'une ou de plusieurs autopsies sont des étapes cruciales dans la résolution du problème.

L'autopsie permet de préciser le diagnostic et d'effectuer, si besoin, des examens complémentaires sur place comme le pH du rumen ou au laboratoire.

La prise de photos tout au long des investigations est une précaution qui peut s'avérer utile en cas de procédure de contre-expertise ou de procédures judiciaires.
La Fièvre Catarrhale Ovine en France :
quel bilan ces 5 dernières années (2016 -2020) ?
Authors: Belbis Guillaume , Bréard Emmanuel , Sailleau Corinne , Viarouge Cyril , Postic Lydie , Vitour Damien , Zientara Stéphan
Published: July 2024

La Fièvre Catarrhale Ovine est réapparue sur le territoire métropolitain après quelques années d’absence. Les sérotypes 4 et 8 sont considérés depuis janvier 2018 comme enzootique en France continentale.

Sur le terrain, les déclarations de cas cliniques sont très faibles par rapport à la première épizootie de BTV-8 (2006-2010) et laissent supposer une pathogénicité moindre : cependant, cette année, des foyers cliniques sont malgré tout rapportés.

Des formes de malformations congénitales et des avortements associés à l’infection sont également rencontrés.
Cet article se propose faire une synthèse sur cette affection virale en 2020.
Les risques liés aux plantes toxiques aux pâturages
Authors: Priymenko Nathalie
Published: July 2024

Les animaux en pâture ou recevant des fourrages conservés sont exposés à une grande variété de plantes non cultivées, dont certaines sont toxiques. Il est donc nécessaire de connaître les plantes herbacées les plus souvent présentes dans les prairies en France, en les classant en trois catégories : les plantes plutôt ubiquistes, celles des milieux plutôt humides et celles des milieux plutôt secs.

L’objectif est de reconnaître ces plantes, de comprendre leur(s) mode(s) de dissémination pour mettre en place des moyens de lutte adaptés. Il est rarement nécessaire par exemple, voire contre-productif de labourer une prairie pour se débarrasser des plantes toxiques qui y sont présentes, avant de ressemer.
Importance des apports de protéines, méthionine et choline
en prépartumsur la production laitière
Authors: Enjalbert Francis , Foucras Gilles
Published: July 2024

Un apport de protéines digestibles au-delà de 800 à 900 g/j en prépartum n’a de l’intérêt que pour des génisses prêtes à vêler, en raison de leurs besoins de croissance, mais devrait s’appliquer à toutes les vaches si les génisses sont groupées avec les vaches taries.

Des suppléments de choline protégée de la dégradation ruminale en péripartum améliorent aussi la production en début de lactation, alors que les apports de méthionine protégée ne semblent pas avoir plus d’intérêt en péripartum que pendant le reste de la lactation.
Déficit fourrager dû à une sécheresse : quelques solutions pratiques
Authors: Grancher Denis
Published: July 2024

Les sécheresses sont très souvent la cause de déficit alimentaire chez les animaux de rente. Pour assurer la santé et la production il est nécessaire de fournir des fourrages (apport de fibres longues) et des concentrés.

L’utilisation de co-produits agroalimentaires s’avère très intéressante avec un approvisionnement simultané suffisant en fourrages.

Les pailles et les céréales immatures peuvent fournir des fibres longues en surveillant la qualité des produits et les risques toxiques.

Pour les co-produits, le choix se fait en fonction de leurs valeurs nutritionnelles respectives, sachant que leur prix est très variable et que ce sont souvent des produits humides.
Using the hybrid undesirable network data envelopment analysis model to evaluate the efficiency of Taiwan’s social care system
Authors: Huang Chin-Wei
Published: July 2024

In this study, a hybrid undesirable network data envelopment analysis model is developed for assessing the efficiency of social care systems. Studies investigating the performance of social care activities have mostly focused on a single social care type. To date, no study has proposed an integrated framework for assessing social care performance. To address this gap in the literature, the developed model incorporates four divisions for a comprehensive performance measurement: disability care, child and youth care, women care, and elderly care. In the model, the government’s expenditure on social care is the initial input, and the efficiency of social care activities in the aforementioned four divisions is evaluated in the second stage. Social care facilities and social care workers serve as the nonradial input and radial input, respectively. Care recipients and those affected by violence serve as the desirable output and undesirable output, respectively, in the second stage. The empirical results have several practical implications for Taiwan’s social care system.
Increasing Generative Artificial Intelligence Competency among Students Enrolled in Doctoral Nursing Research Coursework
Authors: Reading Turchioe Meghan , Kisselev Sergey , Van Bulck Liesbet , Bakken Suzanne
Published: July 2024

Background Generative artificial intelligence (AI) tools may soon be integrated into health care practice and research. Nurses in leadership roles, many of whom are doctorally prepared, will need to determine whether and how to integrate them in a safe and useful way.

Objective This study aimed to develop and evaluate a brief intervention to increase PhD nursing students' knowledge of appropriate applications for using generative AI tools in health care.

Methods We created didactic lectures and laboratory-based activities to introduce generative AI to students enrolled in a nursing PhD data science and visualization course. Students were provided with a subscription to Chat Generative Pretrained Transformer (ChatGPT) 4.0, a general-purpose generative AI tool, for use in and outside the class. During the didactic portion, we described generative AI and its current and potential future applications in health care, including examples of appropriate and inappropriate applications. In the laboratory sessions, students were given three tasks representing different use cases of generative AI in health care practice and research (clinical decision support, patient decision support, and scientific communication) and asked to engage with ChatGPT on each. Students (n = 10) independently wrote a brief reflection for each task evaluating safety (accuracy, hallucinations) and usability (ease of use, usefulness, and intention to use in the future). Reflections were analyzed using directed content analysis.

Results Students were able to identify the strengths and limitations of ChatGPT in completing all three tasks and developed opinions on whether they would feel comfortable using ChatGPT for similar tasks in the future. All of them reported increasing their self-rated competency in generative AI by one to two points on a five-point rating scale.

Conclusion This brief educational intervention supported doctoral nursing students in understanding the appropriate uses of ChatGPT, which may support their ability to appraise and use these tools in their future work.
What Do We Mean by Sharing of Patient Data? DaSH: A Data Sharing Hierarchy of Privacy and Ethical Challenges
Authors: Schreiber Richard , Koppel Ross , Kaplan Bonnie
Published: July 2024

Background Clinical data sharing is common and necessary for patient care, research, public health, and innovation. However, the term “data sharing” is often ambiguous in its many facets and complexities—each of which involves ethical, legal, and social issues. To our knowledge, there is no extant hierarchy of data sharing that assesses these issues.

Objective This study aimed to develop a hierarchy explicating the risks and ethical complexities of data sharing with a particular focus on patient data privacy.

Methods We surveyed the available peer-reviewed and gray literature and with our combined extensive experience in bioethics and medical informatics, created this hierarchy.

Results We present six ways on how data are shared and provide a tiered Data Sharing Hierarchy (DaSH) of risks, showing increasing threats to patients' privacy, clinicians, and organizations as one progresses up the hierarchy from data sharing for direct patient care, public health and safety, scientific research, commercial purposes, complex combinations of the preceding efforts, and among networked third parties. We offer recommendations to enhance the benefits of data sharing while mitigating risks and protecting patients' interests by improving consenting; developing better policies and procedures; clarifying, simplifying, and updating regulations to include all health-related data regardless of source; expanding the scope of bioethics for information technology; and increasing ongoing monitoring and research.

Conclusion Data sharing, while essential for patient care, is increasingly complex, opaque, and perhaps perilous for patients, clinicians, and health care institutions. Risks increase with advances in technology and with more encompassing patient data from wearables and artificial intelligence database mining. Data sharing places responsibilities on all parties: patients, clinicians, researchers, educators, risk managers, attorneys, informaticists, bioethicists, institutions, and policymakers.