bluuebunny/crossref_metadata_2025_split huggingface dataset:
Retinoic acid induces human gastruloids with posterior embryo-like structures
Authors: Hamazaki Nobuhiko , Yang Wei , Kubo Connor A. , Qiu Chengxiang , Martin Beth K. , Garge Riddhiman K. , Regalado Samuel G. , Nichols Eva K. , Pendyala Sriram , Bradley Nicholas , Fowler Douglas M. , Lee Choli , Daza Riza M. , Srivatsan Sanjay , Shendure Jay 
Published: August 2024

AbstractGastruloids are a powerful in vitro model of early human development. However, although elongated and composed of all three germ layers, human gastruloids do not morphologically resemble post-implantation human embryos. Here we show that an early pulse of retinoic acid (RA), together with later Matrigel, robustly induces human gastruloids with posterior embryo-like morphological structures, including a neural tube flanked by segmented somites and diverse cell types, including neural crest, neural progenitors, renal progenitors and myocytes. Through in silico staging based on single-cell RNA sequencing, we find that human RA-gastruloids progress further than other human or mouse embryo models, aligning to E9.5 mouse and CS11 cynomolgus monkey embryos. We leverage chemical and genetic perturbations of RA-gastruloids to confirm that WNT and BMP signalling regulate somite formation and neural tube length in the human context, while transcription factors TBX6 and PAX3 underpin presomitic mesoderm and neural crest, respectively. Looking forward, RA-gastruloids are a robust, scalable model for decoding early human embryogenesis.
Assessment of the errors of high-fidelity two-qubit gates in silicon quantum dots
Authors: Tanttu Tuomo , Lim Wee Han , Huang Jonathan Y. , Dumoulin Stuyck Nard , Gilbert Will , Su Rocky Y. , Feng MengKe , Cifuentes Jesus D. , Seedhouse Amanda E. , Seritan Stefan K. , Ostrove Corey I. , Rudinger Kenneth M. , Leon Ross C. C. , Huang Wister , Escott Christopher C. , Itoh Kohei M. , Abrosimov Nikolay V. , Pohl Hans-Joachim , Thewalt Michael L. W. , Hudson Fay E. , Blume-Kohout Robin , Bartlett Stephen D. , Morello Andrea , Laucht Arne , Yang Chih Hwan , Saraiva Andre , Dzurak Andrew S. 
Published: August 2024

AbstractAchieving high-fidelity entangling operations between qubits consistently is essential for the performance of multi-qubit systems. Solid-state platforms are particularly exposed to errors arising from materials-induced variability between qubits, which leads to performance inconsistencies. Here we study the errors in a spin qubit processor, tying them to their physical origins. We use this knowledge to demonstrate consistent and repeatable operation with above 99% fidelity of two-qubit gates in the technologically important silicon metal-oxide-semiconductor quantum dot platform. Analysis of the physical errors and fidelities in multiple devices over extended periods allows us to ensure that we capture the variation and the most common error types. Physical error sources include the slow nuclear and electrical noise on single qubits and contextual noise that depends on the applied control sequence. Furthermore, we investigate the impact of qubit design, feedback systems and robust gate design to inform the design of future scalable, high-fidelity control strategies. Our results highlight both the capabilities and challenges for the scaling-up of silicon spin-based qubits into full-scale quantum processors.
Facial misfits accelerate stereotype-based associative learning
Authors: Golubickis Marius , Persson Linn M. , Falbén Johanna K. , Seow Siew Hwee , Jalalian Parnian , Sharma Yadvi , Ivanova Margarita , Macrae C. Neil 
Published: August 2024

AbstractCounterstereotypes challenge the deleterious effects that gender-typed beliefs exert on people’s occupational aspirations and lifestyle choices. Surprisingly, however, the critical issue of how readily unexpected person-related knowledge can be acquired remains poorly understood. Accordingly, in two experiments in which the facial appearance of targets was varied to manipulate goodness-of-stereotype-fit (i.e., high vs. low femininity/masculinity), here we used a probabilistic selection task to probe the rate at which counter-stereotypic and stereotypic individuals can be learned. Whether occupational (Expt. 1) or trait-related (Expt. 2) gender stereotypes were explored, a computational analysis yielded consistent results. Underscoring the potency of surprising information (i.e., facial misfits), knowledge acquisition was accelerated for unexpected compared to expected persons, both in counter-stereotypic and stereotypic learning contexts. These findings affirm predictive accounts of social perception and speak to the optimal characteristics of interventions designed to reduce stereotyping outside the laboratory.
Relevance of pre-stimulus oscillatory activity for the perceived valence of emotional facial expressions
Authors: Jaap Carina , Rose Michael 
Published: August 2024

AbstractThe interpretation of emotional facial expressions is crucial in everyday social interactions, and rapid processing of these expressions is necessary. Although extensive research has shed light on the mechanisms involved in facial expression processing, there is limited research on the potential role of the state of neural activity that directly precedes the occurrence of a face. Here, we investigated the potential modulatory role of pre-stimulus oscillatory activity in emotional facial expression processing. We tested emotional facial processing in two experiments, one utilizing artificial and the other natural facial expressions. The participants had to evaluate the emotional valence of the presented ambiguous facial expressions. In a univariate analysis, differences in the oscillation activity of the later rated valence of the faces were observed in both experiments, and these differences were observed even before the presentation of the facial expressions. Importantly, two different multivariate approaches directly supported the relevance of pre-stimulus oscillatory activity by exclusively using pre-stimulus oscillatory data to predict the perceived valence of the latter rated facial expression across the two experiments within as well as across subjects. The behavioral data shows the often observed negativity bias, i.e. ambiguous faces resulted in the tendency to rate them as negative. This negativity bias was related to neural activity modulations in the pre-stimulus period and also within post-stimulus processing related activity. These findings underscore the significance of pre-stimulus oscillatory activity in facial expression processing, indicating a functional role of ongoing neural states that affects the processing of facial expressions and constitute a basis for the well described negativity bias.
Understanding soil factors in corrosion and conservation of buried bronze statuettes: insights for preservation strategies
Authors: Abdelbar Mohamed , El-Shamy Ashraf M. 
Published: August 2024

AbstractThe findings reveal that soil constituents significantly affect the corrosion process. Moisture content and pH promote the formation of corrosion products, while high chloride concentrations accelerate corrosion. Conversely, high organic matter content inhibits corrosion by limiting oxygen diffusion to the metal surface. The effectiveness of conservation treatments, particularly wax or oil-based coatings, varied with soil conditions, showing reduced efficacy in soils with high chloride concentrations. This study underscores the importance of understanding soil constituents for developing effective corrosion and conservation strategies for buried bronze statuettes. The results offer valuable insights for customizing preservation approaches based on soil types. X-ray diffraction (XRD) analysis revealed that mineralogical compositions in soil significantly influence corrosion processes, providing critical insights for effective preservation strategies. pH measurements indicated varying soil acidity and alkalinity levels, crucial in determining corrosion rates and mechanisms, offering essential data for targeted preservation strategies. Additionally, the identification of brochantite and antlerite through Micro-Raman spectroscopy suggests a link to sulfur pollutants from the decomposition of organic matter by sulfate-reducing bacteria, highlighting the potential environmental impact of microbial activity in the soil ecosystem.
Wing vein abnormality analysis in honeybee (Apis mellifera L. 1758) populations from Iran
Authors: Shahshahani Mahdi , Abbasi Roohollah 
Published: August 2024

AbstractThe insect wing is one of the most important characteristics that allowed insects to occupy most of the habitats on the planet. Honeybee wings has been the subject of studies on the venation abnormalities. A total of 424 honeybees from 14 locations were collected and all four wings were removed and examined for 19 abnormalities on the forewings and 6 abnormalities on the hindwings. In general, supernumerary veins were the most common abnormalities seen and abnormalities no. 23, 2, 6, 1, 5, 21, 10, 13 had the highest and abnormalities no. 11, 17, 18, 19, 20, and 25 had the lowest frequencies. All of the abnormalities had similar frequencies in the right and left wings in the population. In terms of correlation between 25 abnormalities, abnormality pairs AB3–AB13, AB6–AB7, AB7–AB8, AB10–AB12, AB16–AB17 on the forewing and AB2–AB23, AB12–AB20, AB12–AB24, AB13–AB21, AB16–AB25, and AB17–AB25 between the forewing and hindwing show significant positive correlations and abnormality pairs AB4–AB5, AB7–AB15 and AB8–AB9 on the forewing show significant negative correlations with each other. In terms of the differential occurrence of abnormalities , a few locations differed significantly from other locations. This study provides some insights into the nature of these abnormalities on the honeybee wings.
Visualisation of in vivo protein synthesis during mycobacterial infection through [68Ga]Ga-DOTA-puromycin µPET/MRI
Authors: Eigner Sebastian , Kleynhans Janke , Beckford Vera Dennis R. , Sathekge Mike M. , Henke Katerina Eigner , Ebenhan Thomas 
Published: August 2024

AbstractRadiolabelled puromycin analogues will allow the quantification of protein synthesis through nuclear medicine-based imaging. A particularly useful application could be the non-invasive longitudinal visualisation of mycobacterial activity through direct quantification of puromycin binding. This study assesses the value of [68Ga]Ga-DOTA-puromycin in the visualisation of mycobacteria through positron emission tomography combined with magnetic resonance imaging (µPET/MRI). The radiopharmaceutical was produced by previously published and validated methods. [68Ga]Ga-DOTA-Puromycin imaging was performed on severe immunodeficient mice infected with Bacille Calmette-Guérin-derived M. Bovis (BCG). Acute and chronic infection stages were examined by µPET/MRI. A follow-up group of animals acted as controls (animals bearing S. aureus-derived infection and sterile inflammation) to assess tracer selectivity. [68Ga]Ga-DOTA-puromycin-µPET/MRI images revealed the acute, widespread infection within the right upper shoulder and armpit. Also, [68Ga]Ga-DOTA-puromycin signal sensitivity measured after a 12-week period was lower than that of [18F]FDG-PET in the same animals. A suitable correlation between normalised uptake values (NUV) and gold standard histopathological analysis confirms accurate tracer accumulation in viable bacteria. The radiopharmaceutical showed infection selectivity over inflammation but accumulated in both M. Bovis and S. Aureus, lacking pathogen specificity. Overall, [68Ga]Ga-DOTA-puromycin exhibits potential as a tool for non-invasive protein synthesis visualization, albeit without pathogen selectivity.
Genetic and epigenetic regulation of cortactin (CTTN) by inflammatory factors and mechanical stress in human lung endothelial cells
Authors: Sun Xiaoguang , Sun Belinda , Sammani Saad , Dudek Steven M , Belvitch Patrick , Camp Sara M. , Zhang Donna , Bime Christian , Garcia Joe G.N. 
Published: August 2024

Abstract
Rationale: Cortactin, an actin-binding cytoskeletal protein, plays a crucial role in maintaining endothelial cell (EC) barrier integrity and regulating vascular permeability. The gene encoding cortactin, CTTN, is implicated in various lung inflammatory disorders. Despite this, the transcriptional regulation of CTTN by inflammatory stimuli and promoter SNPs remains unexplored. Methods: We transfected human lung ECs with a full-length CTTN promoters linked to a luciferase reporter to measure promoter activity. SNP-containing CTTN promoter was created via site-directed mutagenesis. Transfected ECs were exposed to LPS (PAMP), TNF-α (cytokine), cyclic stretch (CS), FG-4592 (HIF-inducer), NRF2 (anti-oxidant modulator), FTY-(S)-phosphate (endothelial barrier enhancer), and 5′-Aza (demethylation inducer). Immunohistochemistry was used to assess cortactin expression in mouse lungs exposed to LPS. Results: LPS, TNF-α, and 18%CS significantly increased CTTN promoter activities in a time-dependent manner (P&lt;0.05). The variant rs34612166 (-212T/C) markedly enhanced LPS- and 18%CS- induced CTTN promoter activities (P&lt;0.05). FG-4592 significantly boosted CTTN promoter activities (P&lt;0.01), which were partially inhibited by HIF1α (KC7F2) and HIF2α (PT2385) inhibitors (P&lt;0.05). NRF2 activator Bixin increased CTTN promoter activities, whereas NRF2 inhibitor Brusatol reduced them (P&lt;0.05). 5′-Aza increased CTTN promoter activities by 2.9-fold (P&lt;0.05). NF-κB response element mutations significantly reduced CTTN promoter activities response to LPS and TNFα. FTY-(S)-phosphate significantly increased CTTN promoter activities in 24 h. In vivo, cortactin levels were significantly elevated in inflammatory mouse lungs exposed to LPS for 18 h. Conclusion: CTTN transcriptional is significantly influenced by inflammatory factors and promoter variants. Cortactin, essential in mitigating inflammatory edema, presents a promising therapeutic target to alleviate severe inflammatory disorders.
EWOCS-II: X-ray properties of the Wolf–Rayet stars in the young Galactic super star cluster Westerlund 1
Authors: Anastasopoulou K. , Guarcello M. G. , Flaccomio E. , Sciortino S. , Benatti S. , De Becker M. , Wright N. J. , Drake J. J. , Albacete-Colombo J. F. , Andersen M. , Argiroffi C. , Bayo A. , Castellanos R. , Gennaro M. , Grebel E. K. , Miceli M. , Najarro F. , Negueruela I. , Prisinzano L. , Ritchie B. , Robberto M. , Sabbi E. , Zeidler P. 
Published: August 2024

Context. Wolf–Rayet (WR) stars are massive evolved stars that exhibit particularly fast and dense stellar winds. Although they constitute a very short phase near the end of a massive star’s life, they play a crucial role in the evolution of massive stars and have a substantial impact on their surrounding environment.
Aims. We present the most comprehensive and deepest X-ray study to date of the properties of the richest Wolf–Rayet population observed in a single stellar cluster, Westerlund 1 (Wd1). By examining the X-ray signatures of WR stars, we aim to shed light on the hottest plasma in their stellar winds and gain insights into whether they exist as single stars or within binary systems.
Methods. This work is based on 36 Chandra observations obtained from the “Extended Westerlund 1 and 2 Open Clusters Survey” (EWOCS) project, plus 8 archival Chandra observations. The overall exposure depth Ms) and baseline of the EWOCS observations extending over more than one year enable us to perform a detailed photometric, colour, and spectral analysis, as well as to search for short- and long-term periodicity.
Results. In X-rays, we detect 20 out of the 24 known Wolf–Rayet stars in Wd1 down to an observed luminosity of ~7 × 1029 erg s−1 (assuming a distance of 4.23 kpc to Wd1), with 8 WR stars being detected in X-rays for the first time. Nine stars show clear evidence of variability over the year-long baseline, with clear signs of periodicity. The X-ray colours and spectral analysis reveal that the vast majority of the WR stars are hard X-ray sources (kT≥2.0 keV). The Fe XXV emission line at ~6.7 keV, which commonly originates from the wind–wind collision zone in binary systems, is detected for the first time in the spectra of 17 WR stars in Wd1. In addition the ~6.4 keV fluorescent line is observed in the spectra of three stars, which are among the very few massive stars exhibiting this line, indicating that dense cold material coexists with the hot gas in these systems. Overall, our X-ray results alone suggest a very high binary fraction (≥80%) for the WR star population in Wd1. When combining our results with properties of the WR population from other wavelengths, we estimate a binary fraction of ≥92%, which could even reach unity. This suggests that either all the most massive stars are found in binary systems within Wd1, or that binarity is essential for the formation of such a rich population of WR stars.
Understanding the star formation efficiency in dense gas: Initial results from the CAFFEINE survey with ArTéMiS
Authors: Mattern M. , André Ph. , Zavagno A. , Russeil D. , Roussel H. , Peretto N. , Schuller F. , Shimajiri Y. , Di Francesco J. , Arzoumanian D. , Revéret V. , De Breuck C. 
Published: August 2024

Context. Despite recent progress, the question of what regulates the star formation efficiency (SFE) in galaxies remains one of the most debated problems in astrophysics. According to the dominant picture, star formation (SF) is regulated by turbulence and feedback, and the SFE is ~1–2% or less per local free-fall time on all scales from Galactic clouds to high-redshift galaxies. In an alternate scenario, the star formation rate (SFR) in galactic disks is linearly proportional to the mass of dense gas above some critical density threshold ~104 cm–3.
Aims. We aim to discriminate between these two pictures thanks to high-resolution submillimeter and mid-infrared imaging observations, which trace both dense gas and young stellar objects (YSOs) for a comprehensive sample of 49 nearby massive SF complexes out to a distance of d ~ 3 kpc in the Galactic disk.
Methods. We used data from CAFFEINE, a complete 350/450 µm survey with APEX/ArTéMiS of the densest portions of all southern molecular clouds at d ≲ 3 kpc, in combination with Herschel data to produce column density maps at a factor of ~4 higher resolution (8") than standard Herschel column density maps (36″). Our maps are free of any saturation effect around luminous high-mass pro-tostellar objects and resolve the structure of dense gas and the typical ~0.1 pc width of molecular filaments out to 3 kpc, which is the most important asset of the present study and is impossible to achieve with Herschel data alone. Coupled with SFR estimates derived from Spitzer mid-infrared observations of the YSO content of the same clouds, this allowed us to study the dependence of the SFE on density in the CAFFEINE clouds. We also combine our findings with existing SF efficiency measurements in nearby clouds to extend our analysis down to lower column densities.
Results. Our results suggest that the SFE does not increase with density above the critical threshold and support a scenario in which the SFE in dense gas is approximately constant (independent of free-fall time). However, the SF efficiency measurements traced by Class I YSOs in nearby clouds are more inconclusive, since they are consistent with both the presence of a density threshold and a dependence on density above the threshold. Overall, we suggest that the SF efficiency in dense gas is primarily governed by the physics of filament fragmentation into protostellar cores.
Limitations and rotation of the two-armed phase spiral in the Milky Way stellar disc
Authors: Alinder S. , McMillan P. J. , Bensby T. 
Published: August 2024

Context. The Milky Way’s history of recent disturbances is vividly demonstrated by a structure in the vertical phase-space distribution known as the Gaia phase spiral. A one-armed phase spiral has been seen widely across the Milky Way disc, while a two-armed one has only been observed in the solar neighbourhood.
Aims. This study aims to determine the properties of the two-armed phase spiral and to put it in a Galactic context, with the ultimate goal of understanding the structure and history of the Milky Way disc.
Methods. The Gaia DR3 data were used to trace and characterise the two-armed phase spiral. Special focus was put on the phase spiral’s spatial distribution, rotational behaviour, and chemical characteristics. To quantify the properties of the phase spiral, we used a model that fits a spiral pattern to the phase space distribution of the stars.
Results. We found that the two-armed phase spiral is detectable only within a narrow range of galactocentric distances and angular momenta in the solar neighbourhood, R = 8 ± 0.5 kpc, LZ = 1450 ± 50 kpc km s−1. Outside this region, the phase spiral is one-armed. The two-armed phase spiral rotates with the phase angle, in a similar way to the one-armed phase spiral, and changes axis ratio with phase angle. Additionally, stars within the phase-space overdensity caused by the two-armed phase spiral pattern have slightly higher mean metallicity than stars in the underdense regions of the pattern at equivalent galactocentric distances, angular momenta, and vertical orbit extents.
Conclusions. The two-armed phase spiral rotates with phase angle and its effect can be seen in metallicity, in a similar way to the one-armed phase spiral. However, the limited range over which it can be found, and its variation in shape are quite different from the one-armed version, suggesting it is a much more localised phenomenon in the Galactic disc.
CMFGEN grids of atmosphere models for massive stars
Authors: Marcolino W. , Bouret J.-C. , Martins F. , Hillier D. J. 
Published: August 2024

Context. Large spectroscopic surveys of individual massive stars, such as ULLYSES and XShootU, provide observational data for hundreds of massive stars. Their analysis requires large numbers of synthetic spectra so that stellar parameters can be determined. In addition, libraries of massive stars’ spectra are needed to produce population synthesis models able to reproduce the observed spectra of unresolved young stellar populations, such as those revealed by the James Webb Space Telescope (JWST) in the early Universe.
Aims. Our main goal is to provide an extensive library of synthetic spectra and spectral energy distributions of OB stars at metallicities of the Magellanic Clouds. This library will offer a wealth of spectrophotometric information, making it readily applicable to a variety of astrophysical problems.
Methods. We used the CMFGEN code to calculate 606 NLTE, line-blanketed, expanding atmosphere models using a comprehensive set of atomic data. An overall metallicity of 1/2 Z⊙ and 1/5 Z⊙ was adopted for the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC), respectively. We produced high-resolution spectra from 30 Å to 3 µm for stars on the Main Sequence and slightly beyond.
Results. We provide spectral energy distributions, normalized synthetic spectra, ionizing fluxes, and photometry in various bands: Johnson UBV, Cousins RI, Bessel JHK, selected wide JWST filters, Gaia, and LSST ugrizy filters. For each of these filters, we compute bolometric corrections for all synthetic spectra and calibrations as a function of effective temperature.
Conclusions. All of our synthetic spectra are publicly available through the POLLUX database, aiming to expedite multiwavelength analyses of massive stars in low metallicity environments.