bluuebunny/crossref_metadata_2025 huggingface dataset:
Brain stimulation with 40 Hz heterochromatic flicker extended beyond red, green, and blue
Authors: Henney Mark Alexander , Carstensen Marcus , Thorning-Schmidt Martin , Kubińska Marta , Grønberg Manja Gersholm , Nguyen Mai , Madsen Kristoffer Hougaard , Clemmensen Line Katrine Harder , Petersen Paul Michael
Published: January 2024

Alzheimer’s disease (AD) is associated with electrophysiological changes in the brain. Pre-clinical and early clinical trials have shown promising results for the possible therapy of AD with 40 Hz neurostimulation. The most notable findings used stroboscopic flicker, but this technique poses an inherent barrier for human applications due to its visible flickering and resulting high level of perceived discomfort. Therefore, alternative options should be investigated for entraining 40 Hz brain activity with light sources that appear less flickering. Previously, chromatic flicker based on red, green, and blue (RGB) have been studied in the context of brain-computer interfaces, but this is an incomplete representation of the colours in the visual spectrum. This study introduces a new kind of heterochromatic flicker based on spectral combinations of blue, cyan, green, lime, amber, and red (BCGLAR). These combinations are investigated by the steady-state visually evoked potential (SSVEP) response from the flicker with an aim of optimising the choice of 40 Hz light stimulation with spectrally similar colour combinations in BCGLAR space. Thirty healthy young volunteers were stimulated with heterochromatic flicker in an electroencephalography experiment with randomised complete block design. Responses were quantified as the 40 Hz signal-to-noise ratio and analysed using mixed linear models. The size of the SSVEP response to heterochromatic flicker is dependent on colour combinations and influenced by both visual and non-visual effects. The amber-red flicker combination evoked the highest SSVEP, and combinations that included blue and/or red consistently evoked higher SSVEP than combinations only with mid-spectrum colours. Including a colour from either extreme of the visual spectrum (blue and/or red) in at least one of the dyadic phases appears to be more important than choosing pairs of colours that are far from each other on the visual spectrum. Spectrally adjacent colour pairs appear less flickering to the perceiver, and thus the results motivate investigations into the limits for how alike the two phases can be and still evoke a 40 Hz response. Specifically, combining a colour on either extreme of the visual spectrum with another proximal colour might provide the best trade-off between flickering sensation and SSVEP magnitude.
Analysis of the longitudinal stability of human plasma miRNAs and implications for disease biomarkers
Authors: Sandau Ursula S. , Wiedrick Jack T. , McFarland Trevor J. , Galasko Douglas R. , Fanning Zoe , Quinn Joseph F. , Saugstad Julie A.
Published: January 2024

There is great interest in developing clinical biomarker assays that can aid in non-invasive diagnosis and/or monitoring of human diseases, such as cancer, cardiovascular disease, and neurological diseases. Yet little is known about the longitudinal stability of miRNAs in human plasma. Here we assessed the intraindividual longitudinal stability of miRNAs in plasma from healthy human adults, and the impact of common factors (e.g., hemolysis, age) that may confound miRNA data. We collected blood by venipuncture biweekly over a 3-month period from 22 research participants who had fasted overnight, isolated total RNA, then performed miRNA qPCR. Filtering and normalization of the qPCR data revealed amplification of 134 miRNAs, 74 of which had high test–retest reliability and low percentage level drift, meaning they were stable in an individual over the 3-month time period. We also determined that, of nuisance factors, hemolysis and tobacco use have the greatest impact on miRNA levels and variance. These findings support that many miRNAs show intraindividual longitudinal stability in plasma from healthy human adults, including some reported as candidate biomarkers for Alzheimer’s disease.
Dihydroartemisinin-piperaquine effectiveness for seasonal malaria chemoprevention in settings with extended seasonal malaria transmission in Tanzania
Authors: Mwaiswelo Richard , Ngasala Billy , Chaky Frank , Molteni Fabrizio , Mohamed Ally , Lazaro Samwel , Samwel Bushukatale , Mmbando Bruno P.
Published: January 2024

Effectiveness of dihydroartemisinin-piperaquine (DP) as seasonal malaria chemoprevention (SMC) was assessed in Nanyumbu and Masasi Districts. Between March and June 2021, children aged 3–59 months were enrolled in a cluster randomized study. Children in the intervention clusters received a monthly, 3-days course of DP for three consecutive months regardless of malaria infection status, and those in the control clusters received no intervention. Malaria infection was assessed at before the first-round and at 7 weeks after the third-round of DP in both arms. Malaria prevalence after the third-round of DP administration was the primary outcome. Chi-square tests and logistic regression model were used to compare proportions and adjust for explanatory variables. Before the intervention, malaria prevalence was 13.7% (161/1171) and 18.2% (212/1169) in the intervention and control clusters, respectively, p < 004. Malaria prevalence declined to 5.8% (60/1036) in the intervention clusters after three rounds of DP, and in the control clusters it declined to 9.3% (97/1048), p = 0.003. Unadjusted and adjusted prevalence ratios between the intervention and control arms were 0.42 (95%CI 0.32–0.55, p < 0.001) and 0.77 (95%CI 0.53–1.13, p = 0.189), respectively. SMC using DP was effective for control of malaria in the two Districts.

Trial registration: NCT05874869, https://clinicaltrials.gov/ 25/05/2023.
A secretory protein neudesin regulates splenic red pulp macrophages in erythrophagocytosis and iron recycling
Authors: Nakayama Yoshiaki , Masuda Yuki , Mukae Takehiro , Mikami Tadahisa , Shimizu Ryohei , Kondo Naoto , Kitagawa Hiroshi , Itoh Nobuyuki , Konishi Morichika
Published: January 2024

Neudesin, originally identified as a neurotrophic factor, has primarily been studied for its neural functions despite its widespread expression. Using 8-week-old neudesin knockout mice, we elucidated the role of neudesin in the spleen. The absence of neudesin caused mild splenomegaly, shortened lifespan of circulating erythrocytes, and abnormal recovery from phenylhydrazine-induced acute anemia. Blood cross-transfusion and splenectomy experiments revealed that the shortened lifespan of erythrocytes was attributable to splenic impairment. Further analysis revealed increased erythrophagocytosis and decreased iron stores in the splenic red pulp, which was linked to the upregulation of Fcγ receptors and iron-recycling genes in neudesin-deficient macrophages. In vitro analysis confirmed that neudesin suppressed erythrophagocytosis and expression of Fcγ receptors through ERK1/2 activation in heme-stimulated macrophages. Finally, we observed that 24-week-old neudesin knockout mice exhibited severe symptoms of anemia. Collectively, our results suggest that neudesin regulates the function of red pulp macrophages and contributes to erythrocyte and iron homeostasis.
Last Glacial Maximum cooling induced positive moisture balance and maintained stable human populations in Australia
Authors: Cadd Haidee , Williams Alan N. , Saktura Wanchese M. , Cohen Tim J. , Mooney Scott D. , He Chengfei , Otto‐Bliesner Bette , Turney Chris S. M.
Published: January 2024

Long-standing interpretations of the Last Glacial Maximum (21,000 ± 2000 years ago) in Australia suggest that the period was extremely cold and arid, during which the Indo-Australian summer monsoon system collapsed, and human populations declined and retreated to ecological refuges to survive. Here, we use transient iTRACE simulations, combined with palaeoclimate proxy records and archaeological data to re-interpret the late Last Glacial Maximum and terminal Pleistocene (21,000 – 11,000 years) in Australia. The model suggests climates during the peak Last Glacial Maximum were cooler than present (−4 to −11 °C), but there is no evidence of monsoon collapse or substantial decreases in moisture balance across Australia. Kernel Density Estimates of archaeological ages show relatively stable and persistent human activity across most regions throughout the late Last Glacial Maximum and terminal Pleistocene, consistent with genetic evidence. Spatial coverage of archaeological sites steadily increased across the terminal Pleistocene; however, substantial population change is not evident.
Synthesis of 1,4-epoxy-2-aryltetrahydro-1-benzazepines via rhodium(iii)-catalyzed C–H allylation/intramolecular 1,3-dipolar cycloaddition
Authors: Wang Xuan , Li Jianlong , Du Haifang , Liang Weihong , Luo Cheng , Wu Yunshan , Liu Bo
Published: January 2024

We have developed a new synthetic route to 1,4-epoxy-2-aryltetrahydro-1-benzazepine derivatives with high efficiency via Rh(iii)-catalyzed C–H allylation/1,3-dipolar cycloaddition cascade reactions by employing nitrones and allyl precursors.
Metal-driven folding and assembly of a minimal β-sheet into a 3D-porous honeycomb framework
Authors: Bajpayee Nikhil , Pophali Salil , Vijayakanth Thangavel , Nandi Shyamapada , Desai Aamod V. , Kumar Vinod , Jain Rahul , Bera Santu , Shimon Linda J. W. , Misra Rajkumar
Published: January 2024

Metal-mediated supramolecular assembly of a minimal β-sheet peptide revealed a hetero terminal peptide assembled into a 3D porous honeycomb framework.
Dual-targets fluorescent nanoprobe for precise subtyping of lung cancer
Authors: Chang Zixuan , Jia Ming , Liu Gao , Yang Houbang , Wang Yinian , Ouyang Mingyi , Gao Xiaonan , Tang Bo
Published: January 2024

A florescent nanoprobe for simultaneous detection of Pro-GRP protein and Cyfra21-1 was developed. Early diagnosis and subtyping of lung cancer can be achieved based on the nanoprobes’ differential response to the two targets in patients’ serum.
Artificial spinal dura mater made of gelatin microfibers and bioadhesive for preventing cerebrospinal fluid leakage
Authors: Sun Shengdong , Luo Hao , Wang Yuanfei , Xi Yongming , Fang Kuanjun , Wu Tong
Published: January 2024

Artificial spinal dura mater was designed by combining solution blow-spun gelatin microfibers and dopamine-capped polyurethane bioadhesive.
Multiphoton emission of single CdZnSe/ZnS quantum dots coupled with plasmonic Au nanoparticles
Authors: Xie Luogang , Yang Hongjun , Yang Yang , Chen Ziyang , Li Hangtian , Li Zijiong , Liu Dewei
Published: January 2024

Single QDs coupled with Au nanoparticles exhibit fluorescence enhancement, suppressed blinking, lifetime shortening, and multiphoton emission.
Top-down design of high-performance V-based MBene anode for Li/Na-ion batteries
Authors: Li Shaohan , Sun Weiwei , Zhu Tingwei , Wang Siwei , Zhang Jing , Yu Jin , Zheng Wei , Ying Guobing , Sun Litao , Geng Huayun
Published: January 2024

Novel V-based MBenes are predicted and screened using a global search for precursors and surface functionalization, leading to the identification of V4B6S2 as an anode for lithium-ion batteries (LIBs).
Molecular crowding effect in Hantzch pyridine synthesis in polyethylene glycol aqueous solution
Authors: Miyagawa Akihisa , Ueda Yasuyuki , Nakatani Kiyoharu
Published: January 2024

The present study kinetically revealed that an organic synthesis reaction in a molecular crowding environment can be explained by the effects of excluded volume and osmotic pressure.
Marbofloxacin combined with heavy rare-earth ions makes better candidates for veterinary drugs: crystal structure and bio-activity studies
Authors: Chen Zhi-chuan , Liu Rui-xue , Xie Yan-jie , Hu Qin , Huang Fu-ping , Liu Yan-cheng , Liang Hong
Published: January 2024

Marbofloxacin (MB) combined with heavy rare earth ion makes a series of MB-Ln complexes, who exhibit similar antibacterial activity to MB, but much lower in vivo acute toxicity than MB, suggesting their better medicinal prospect as veterinary drugs.
Systematic rare Earth doping to adopt an R32 type huntite structure in NdSc3(BO3)4 crystals
Authors: Kuznetsov Artem B. , Kokh Konstantin A. , Kaneva Ekaterina V. , Jamous Ammar Y. , Svetlichnyi Valery A. , Kononova Nadezda G. , Shevchenko Vyacheslav S. , Goreiavcheva Anastasia A. , Kokh Aleksander E.
Published: January 2024

This study is focused on determining the type and quantity of REE impurities responsible for converting the structure of NdSc3(BO3)4 into an R32 polymorph.
Chemoselective Luche-type reduction of α,β-unsaturated ketones by aluminium hydride catalysis
Authors: Yan Ben , Ma Xiaoli , Pang Ziyuan , Yang Zhi
Published: January 2024

Herein, we describe a greener and more general method for the chemoselective reduction of α,β-unsaturated ketones using organoaluminum catalysis.
Assessing the importance of nitric acid and ammonia for particle growth in the polluted boundary layer
Authors: Marten Ruby , Xiao Mao , Wang Mingyi , Kong Weimeng , He Xu-Cheng , Stolzenburg Dominik , Pfeifer Joschka , Marie Guillaume , Wang Dongyu S. , Elser Miriam , Baccarini Andrea , Lee Chuan Ping , Amorim Antonio , Baalbaki Rima , Bell David M. , Bertozzi Barbara , Caudillo Lucía , Dada Lubna , Duplissy Jonathan , Finkenzeller Henning , Heinritzi Martin , Lampimäki Markus , Lehtipalo Katrianne , Manninen Hanna E. , Mentler Bernhard , Onnela Antti , Petäjä Tuukka , Philippov Maxim , Rörup Birte , Scholz Wiebke , Shen Jiali , Tham Yee Jun , Tomé António , Wagner Andrea C. , Weber Stefan K. , Zauner-Wieczorek Marcel , Curtius Joachim , Kulmala Markku , Volkamer Rainer , Worsnop Douglas R. , Dommen Josef , Flagan Richard C. , Kirkby Jasper , McPherson Donahue Neil , Lamkaddam Houssni , Baltensperger Urs , El Haddad Imad
Published: January 2024

Inhomogeneities in temperature and ammonia concentrations can cause rapid growth of nanoparticles in polluted environments.
Enhancing spatial inference of air pollution using machine learning techniques with low-cost monitors in data-limited scenarios
Authors: Kamigauti Leonardo Y. , Perez Gabriel M. P. , Martin Thomas C. M. , de Fatima Andrade Maria , Kumar Prashant
Published: January 2024

Our novel approach leverages accessible datasets and deep learning to achieve accurate air quality modeling in resource-limited environments.
Unlocking a nutritional treasure: health benefits and sustainable applications of spent coconut meal
Authors: Shakeela Heeba , Mohan Kavya , P Nisha
Published: January 2024

This paper investigates the previously overlooked potential of spent coconut meal, a byproduct resulting from the extraction of virgin coconut oil with a residual oil content of 25–54%.
Abortive reaction leads to selective adsorbate rotation
Authors: Lai Yi-Fang , Leung Lydie , Timm Matthew J. , Walker Gilbert C. , Polanyi John C.
Published: January 2024

Collision between an F-atom recoiling along the red arrow and a co-adsorbed allyl radical on Cu(110) leads to unidirectional rotation of the allyl, clockwise or anti-clockwise, as the result of an abortive abstraction reaction.
Efficient photocatalytic CO2 reduction coupled with selective styrene oxidation over a modified g-C3N4/BiOBr composite with high atom economy
Authors: Bai Peng , Zhao Yicheng , Li Yongdan
Published: January 2024

A modified g-C3N4/BiOBr composite is developed for photocatalytic CO2 reduction to CO coupled with selective styrene oxidation.
A comparison of calibration strategies for quantitative laser ablation ICP-mass spectrometry (LA-ICP-MS) analysis of fused catalyst samples
Authors: Rua-Ibarz Ana , Van Acker Thibaut , Bolea-Fernandez Eduardo , Boccongelli Marina , Vanhaecke Frank
Published: January 2024

Alternative calibration approaches relying on either aqueous standard solutions or a single solid standard measured under different LA settings, were evaluated in the context of quantitative LA-ICP-MS bulk analysis of fused catalyst samples.
Hydrogenation of nitriles to primary amines over a highly dispersed Ni/SiC catalyst without ammonia addition
Authors: Jiao Zhi-Feng , Zheng Zhi-Yuan , Zhao Ji-Xiao , Zhang Cheng-Du , Xu Tian-Yu , Guo Xiang-Yun
Published: January 2024

Ni/SiC showed high performance for the hydrogenation of nitriles to primary amines without ammonia addition, which may originate from the natural properties of SiC and highly dispersed Ni species.
Simple hybrid polymeric nanostructures encapsulating macro-cyclic Gd/Eu based complexes: luminescence properties and application as MRI contrast agent
Authors: Yon Marjorie , Esmangard Lucie , Enel Morgane , Desmoulin Franck , Pestourie Carine , Leygue Nadine , Mingotaud Christophe , Galaup Chantal , Marty Jean-Daniel
Published: January 2024

Lanthanide-based macrocycles are integrated into hybrid polyionic complexes by combining them with zirconium ions and a solution of double-hydrophilic block copolymer.
Antisolvent solubilization achieves simultaneous passivation of shallow and deep defects in perovskite solar cells
Authors: Zhang Chu , Ma Chunying , Chen Shennan , Ma Tingli
Published: January 2024

An antisolvent solubilization (AS) approach has been developed to enhance the solubilization of the bulk organic ammonium salt and passivated both shallow and deep defects of perovskites, which increased the PCE and stability of PSCs.
Rapid deterioration in buried leather: archaeological implications
Authors: H. H. Halldórsdóttir , R. Williams , E. M. Greene , G. Taylor
Published: January 2024

Understanding archaeological leather degradation helps inform economies, crafts, and technologies of historic communities.
Post-treatment strategies for pyrophoric KOH-activated carbon nanofibres
Authors: Fischer Tom , Kretzschmar Ansgar , Selmert Victor , Jovanovic Sven , Kungl Hans , Tempel Hermann , Eichel Rüdiger-A.
Published: January 2024

The effect of two atmospheric post-treatment conditions directly after the KOH activation of polyacrylonitrile-based carbon nanofibres is studied in this work. Vigorous potassium oxidation reactions could be avoided by a low O2-flow treatment.
Correction: The origins of formic acid electrooxidation on selected surfaces of Pt, Pd, and their alloys with Sn
Authors: Yadav Radhey Shyam , Gebru Medhanie Gebremedhin , Teller Hanan , Schechter Alex , Kornweitz Haya
Published: January 2024

Correction for ‘The origins of formic acid electrooxidation on selected surfaces of Pt, Pd, and their alloys with Sn’ by Radhey Shyam Yadav et al., J. Mater. Chem. A, 2024, https://doi.org/10.1039/d3ta07219c.
The mTORC2 signaling network: targets and cross-talks
Authors: Ragupathi Aparna , Kim Christian , Jacinto Estela
Published: January 2024

The mechanistic target of rapamycin, mTOR, controls cell metabolism in response to growth signals and stress stimuli. The cellular functions of mTOR are mediated by two distinct protein complexes, mTOR complex 1 (mTORC1) and mTORC2. Rapamycin and its analogs are currently used in the clinic to treat a variety of diseases and have been instrumental in delineating the functions of its direct target, mTORC1. Despite the lack of a specific mTORC2 inhibitor, genetic studies that disrupt mTORC2 expression unravel the functions of this more elusive mTOR complex. Like mTORC1 which responds to growth signals, mTORC2 is also activated by anabolic signals but is additionally triggered by stress. mTORC2 mediates signals from growth factor receptors and G-protein coupled receptors. How stress conditions such as nutrient limitation modulate mTORC2 activation to allow metabolic reprogramming and ensure cell survival remains poorly understood. A variety of downstream effectors of mTORC2 have been identified but the most well-characterized mTORC2 substrates include Akt, PKC, and SGK, which are members of the AGC protein kinase family. Here, we review how mTORC2 is regulated by cellular stimuli including how compartmentalization and modulation of complex components affect mTORC2 signaling. We elaborate on how phosphorylation of its substrates, particularly the AGC kinases, mediates its diverse functions in growth, proliferation, survival, and differentiation. We discuss other signaling and metabolic components that cross-talk with mTORC2 and the cellular output of these signals. Lastly, we consider how to more effectively target the mTORC2 pathway to treat diseases that have deregulated mTOR signaling.
Efficacy of Amplification for Tinnitus Relief in People With Mild Hearing Loss
Authors: Kam Anna Chi Shan
Published: January 2024

Purpose:

The study aimed to evaluate the efficacy of amplification with hearing aids for people with chronic subjective tinnitus and mild hearing loss.

Method:

In this randomized, controlled, three-arm trial, 38 subjects with a primary complaint of tinnitus were randomly assigned to one of the three treatment groups. Twelve subjects received informational counselling (IC) only, 13 received IC with hearing aid fitting, and 13 subjects received IC with individualized music stimulation for 12 months. The primary efficacy analysis in tinnitus severity was based on the change from baseline to 12 months after the 1st day of the intervention. Secondary outcome measures included tinnitus impact, psychological and mental health effects, subjective ratings, and psychoacoustically measured tinnitus loudness.

Results:

A statistically significant treatment difference among the three groups in the Chinese Tinnitus Functional Index (TFI-CH) total score at the predefined end point in Month 12 was observed (
F
= 3.34,
p
= .04, partial η
2
= .16). Reductions in the TFI-CH scores in both the hearing aid and the customized music group were more prominent than in the IC-only group. Only the hearing aid group showed a significantly greater treatment effect than the IC-only group.

Conclusion:

Results from this study support that a combination of hearing aid use and IC can help improve tinnitus in people with mild hearing loss.

Supplemental Material:

https://doi.org/10.23641/asha.25015979
A comprehensive review on enhancing wind turbine applications with advanced SCADA data analytics and practical insights
Authors: Pandit Ravi , Wang Jianlin
Published: January 2024

The aim of this study is to explore the potential and economic benefits of utilising Supervisory Control and Data Acquisition (SCADA) data to improve wind turbine operation and maintenance activities. The review identifies a gap in the current understanding of how to effectively use SCADA data in wind turbine applications. It emphasises the need for pre‐processing SCADA data to ensure data integrity by addressing outliers and employing interpolation techniques. Additionally, it highlights the challenges associated with early fault detection methods using SCADA data, including the development of physical models, data‐driven machine learning models, and statistical regression models. The review also recognises the limitations caused by the lack of public data from wind turbine developers and the imbalance between normal operation data samples and abnormal data samples, negatively impacting model accuracy. The key findings of the review demonstrate that SCADA data‐driven techniques can lead to significant improvements in wind turbine operations and maintenance. The application of data‐driven technologies based on SCADA data has proven effective in reducing operation and maintenance costs and enhancing wind power generation. Moreover, the development of robust decision support systems using SCADA data minimises the need for frequent maintenance interventions in offshore wind farms. To bridge the gap and further enhance wind turbine applications using SCADA data, several recommendations are provided. These include encouraging greater openness in sharing SCADA data to improve the robustness and accuracy of AI models, adopting transfer learning techniques to overcome the scarcity of quality datasets, establishing unified standards and taxonomies, and providing specialised resources such as software applications with interactive graphical user interfaces for easier storage, annotation, and analysis of SCADA data.

The authors’ review paper identifies a gap in the current understanding of how to effectively utilise SCADA data in wind turbine applications. It emphasises the importance of pre‐processing SCADA data to ensure data integrity by addressing outliers and employing interpolation techniques. Furthermore, the authors highlight the challenges associated with early fault detection methods using SCADA data, including the development of physical models, data‐driven machine learning models, and statistical regression models.
FORKLENS: Accurate weak-lensing shear measurement with deep learning
Authors: Zhang Zekang , Shan Huanyuan , Li Nan , Wei Chengliang , Yao Ji , Ban Zhang , Fang Yuedong , Guo Qi , Liu Dezi , Li Guoliang , Lin Lin , Li Ming , Li Ran , Li Xiaobo , Luo Yu , Meng Xianmin , Nie Jundan , Qi Zhaoxiang , Qiu Yisheng , Shao Li , Tian Hao , Wang Lei , Wang Wei , Xian Jingtian , Xu Youhua , Zhang Tianmeng , Zhang Xin , Zhou Zhimin
Published: January 2024

Context. Weak gravitational lensing is one of the most important probes of the nature of dark matter and dark energy. In order to extract cosmological information from next-generation weak lensing surveys (e.g., Euclid, Roman, LSST, and CSST) as much as possible, accurate measurements of weak lensing shear are required.

Aims. There are existing algorithms to measure the weak lensing shear on imaging data, which have been successfully applied in previous surveys. In the meantime, machine learning (ML) has been widely recognized in various astrophysics applications in modeling and observations. In this work, we present a fully deep-learning-based approach to measuring weak lensing shear accurately.

Methods. Our approach comprises two modules. The first one contains a convolutional neural network (CNN) with two branches for taking galaxy images and point spread function (PSF) simultaneously, and the output of this module includes the galaxy’s magnitude, size, and shape. The second module includes a multiple-layer neural network (NN) to calibrate weak-lensing shear measurements. We name the program FORKLENS and make it publicly available online.

Results. Applying FORKLENS to CSST-like mock images, we achieve consistent accuracy with traditional approaches (such as moment-based measurement and forward model fitting) on the sources with high signal-to-noise ratios (S/N > 20). For the sources with S/N < 10, FORKLENS exhibits an ~36% higher Pearson coefficient on galaxy ellipticity measurements.

Conclusions. After adopting galaxy weighting, the shear measurements with FORKLENS deliver accuracy levels to 0.2%. The whole procedure of FORKLENS is automated and costs about 0.7 milliseconds per galaxy, which is appropriate for adequately taking advantage of the sky coverage and depth of the upcoming weak lensing surveys.
CMEs evolve in the interplanetary medium to double their predicted geo-effectiveness
Authors: Soni Shirsh Lata , Maharana Anwesha , Guerrero Antonio , Mishra Wageesh , Poedts Stefaan , Thampi Smitha , Akhavan-Tafti Mojtaba
Published: January 2024

Context. We explore the impact of interactions between coronal mass ejections (CMEs) – known as CME–CME interactions – on Earth using remote-sensing and in situ observations and estimate the amplification of the geo-effectiveness of the individual CMEs by a factor of ∼2 due to CME–CME interactions.

Aims. We present 3D reconstructions of interacting CMEs, which provide essential information on the orientation and interaction of the events. Additionally, we analysed coronal evolution of CMEs and their in situ characteristics at 1 AU to explore the impact of interactions between CMEs on their geo-effectiveness.

Methods. We analysed CME interaction using white light data from LASCO and STEREO COR-A. The reported CMEs were reconstructed using the gradual cylindrical shell (GCS) model and simulated self-consistently with the physics-based 3D MHD model EUHFORIA (EUropean Heliosphere FORecasting Information Asset). By running different simulations, we estimated the geo-effectiveness of both individual and interacting CMEs using an empirical relationship method for the disturbance storm index.

Results. The SOHO/LASCO spacecraft observed three CMEs erupting from the Sun within an interval of 10 h during a very active period in early November 2021. There were two partial halo CMEs that occurred on 1 Nov. 2021 at 19:00 UT and 22:00 UT, respectively, from the active region 12887 (S28W58), and a third halo CME occurred from AR 12891 (N17E03) on 2 Nov. 2021 at 02:48 UT. By combining remote observations close to the Sun, in situ data at 1 AU, and further numerical analyses of each individual CME, we are able to identify the initial and interplanetary evolution of the CMEs.

Conclusions. (i) White light observations and a 3D reconstruction of the CMEs show cannibalism by CME-2 on CME-1 and a flank interaction of CME-3 with the merged CME-1 and CME-2 at 45–50 Rs. (ii) Interacting CMEs exhibit an increase in geo-effectiveness compared to an individual CME.
Multithermal apparent damping of slow waves due to strands with a Gaussian temperature distribution
Authors: Van Doorsselaere T. , Krishna Prasad S. , Pant V. , Banerjee D. , Hood A.
Published: January 2024

Context. Slow waves in solar coronal loops are strongly damped, but the current theory of damping by thermal conduction cannot explain some observational features.

Aims. We investigated the propagation of slow waves in a coronal loop built up from strands of different temperatures.

Methods. We considered the loop to have a multithermal, Gaussian temperature distribution. The different propagation speeds in different strands led to a multithermal apparent damping of the wave, similar to observational phase mixing. We used an analytical model to predict the damping length and propagation speed for the slow waves, including in imaging with filter telescopes.

Results. We compared the damping length due to this multithermal apparent damping with damping due to thermal conduction and found that the multithermal apparent damping is more important for shorter period slow waves. We quantified the influence of instrument filters on the wave’s propagation speed and damping. This allowed us to compare our analytical theory to forward models of numerical simulations.

Conclusions. We find that our analytical model matches the numerical simulations very well. Moreover, we offer an outlook for using the slow wave properties to infer the loop’s thermal properties.
Atmospheric properties of AF Lep b with forward modeling
Authors: Palma-Bifani P. , Chauvin G. , Borja D. , Bonnefoy M. , Petrus S. , Mesa D. , De Rosa R. J. , Gratton R. , Baudoz P. , Boccaletti A. , Charnay B. , Desgrange C. , Tremblin P. , Vigan A.
Published: January 2024

Context. About a year ago, a super-Jovian planet was directly imaged around the nearby young solar-type star AF Lep. The 2.8 MJup planet orbiting at a semimajor axis of 8.2 au matches the predicted location based on the HIPPARCOS-Gaia astrometric acceleration.

Aims. Our aim is to expand the atmospheric exploration of AF Lep b by modeling all available observations obtained with SPHERE at VLT (in the range 0.95–1.65, at 2.105, and at 2.253 µm), and NIRC2 at Keck (at 3.8 µm) with self-consistent atmospheric models.

Methods. To understand the physical properties of this exoplanet, we used ForMoSA. This forward-modeling code compares observations with grids of pre-computed synthetic atmospheric spectra using Bayesian inference methods. We used Exo-REM, an atmospheric radiative-convective equilibrium model, including the effects of nonequilibrium processes and clouds.

Results. From the atmospheric modeling we derived solutions at the low Teff of ~750 K. Our analysis also favors a metal-rich atmosphere (>0.4) and solar to super-solar carbon-to-oxygen ratio (~0.6). We tested the robustness of the estimated values for each parameter by cross-validating our models using the leave-one-out strategy, where all points are used iteratively as validation points. Our results indicate that the photometry point at 3.8 µm strongly drives the metal-rich and super-solar carbon-to-oxygen solutions.

Conclusions. Our atmospheric forward-modeling analysis strongly supports the planetary nature of AF Lep b. Its spectral energy distribution is consistent with that of a young, cold, early-T super-Jovian planet. We recover physically consistent solutions for the surface gravity and radius, which allows us to reconcile atmospheric forward modeling with evolutionary models, in agreement with the previously published complementary analysis done by retrievals. Finally, we identified that future data at longer wavelengths are necessary before we can conclude about the metal-rich nature of AF Lep b.
Magnetically driven winds from accretion disks in post-asymptotic giant branch binaries
Authors: Verhamme Olivier , Kluska Jacques , Ferreira Jonathan , Bollen Dylan , De Prins Toon , Kamath Devika , Van Winckel Hans
Published: January 2024

Context. Jets are commonly detected in post-asymptotic giant branch (post-AGB) binaries and originate from an accretion process onto the companion of the post-AGB primary. These jets are revealed by high-resolution spectral time series.

Aims. This paper is part of a series. In this work, we move away from our previous parametric modelling and include a self-similar wind model that allows the physical properties of post-AGB binaries to be characterised. This model describes magnetically driven jets from a thin accretion disk threaded by a large-scale, near equipartition vertical field.

Methods. We expanded our methodology in order to simulate the high-resolution dynamic spectra coming from the obscuration of the primary by the jets launched by the companion. We present the framework to exploit the self-similar jet models for post-AGB binaries. We performed a parameter study to investigate the impact of different parameters (inclination, accretion rate, inner and outer launching radius) on the synthetic spectra.

Results. We successfully included the physical jet models into our framework. The synthetic spectra have a very similar orbital phase coverage and absorption strengths as the observational data. The magnetohydrodynamic (MHD) jet models provide a good representation of the actual jet creation process in these evolved binaries. Challenges remain, however, as the needed high-accretion rate would induce accretion disks that are too hot in comparison to the data. Moreover, the rotational signature of the models is not detected in the observations. In future research, we will explore models with a higher disk ejection efficiency and even lower magnetisation in order to solve some of the remaining discrepancies between the observed and synthetic dynamic spectra.
Formation of a streamer blob via the merger of multiple plasma clumps below 2 R⊙
Authors: Li Haiyi , Huang Zhenghua , Deng Kaiwen , Fu Hui , Xia Lidong , Song Hongqiang , Xiong Ming , Wei Hengyuan , Qi Youqian , Zhang Chao
Published: January 2024

Context. Propagating streamer blobs could be an important source of disturbances in the solar wind. Direct observations of the formation of streamer blobs could be a proxy for understanding the formation of small-scale structures and disturbances in the solar wind.

Aims. We aim to investigate how a streamer blob is formed before it is observed in the outer corona.

Methods. Using special coordinated observations from SOHO/LASCO, GOES/SUVI, and SDO/AIA, we studied the precursors of a streamer blob seen in the corona below 2.0 solar radii (R⊙).

Results. We find that the streamer blob formed due to the gradual merging of three clumps of brightenings initiated from the lower corona at about 1.8 R⊙, which was likely driven by the expansion of the loop system at the base of the streamer. The acceleration of the blob starts at 1.9 R⊙ or lower. It propagates along the south flank of the streamer, where an expanding elongated brightening occurs coincidentally.

Conclusions. Our observations demonstrate that formation of a streamer blob is a complex process. We suggest that the expansion of the loop results in a pinching-off flux-rope-like blob at the loop apex below 2 R⊙. When the blob moves outward, it can be transferred across the overlying loops through interchange or component magnetic reconnection and is then released into the open field system. When the blob moves toward open field lines, interchange magnetic reconnection might also occur, and that can accelerate the plasma blob intermittently, while allowing it to transfer across the open field lines. Such dynamics in a streamer blob might further trigger small-scale disturbances in the solar wind such as switchbacks in the inner heliosphere.
Probing the two-body decaying dark matter scenario with weak lensing and the cosmic microwave background
Authors: Bucko Jozef , Giri Sambit K. , Peters Fabian Hervas , Schneider Aurel
Published: January 2024

Decaying dark matter (DDM) scenarios have recently regained attention due to their potential ability to resolve the well-known clustering (orS8) tension between weak lensing (WL) and cosmic microwave background (CMB) measurements. In this paper, we investigate a well-established model where the original dark matter particle decays into a massless particle and a massive daughter particle. The latter obtains a velocity kick during the decay process that results in the suppression of the matter power spectrum at scales that are observable with WL shear observations. We perform the first fully non-linear WL analysis of this two-body decaying dark matter (ΛDDM) scenario, including intrinsic alignment and baryonic feedback processes. We used the cosmic shear band power spectra from KiDS-1000 data and combined it with temperature and polarisation data fromPlanckin order to constrain the ΛDDM model. We report new limits on the decay rate and mass splitting parameters that are significantly stronger than previous results, especially in the case of low-mass splittings. Regarding theS8tension, we found a reduction from about 3 to 2σ, depending on which statistical measure is applied. We therefore conclude that the two-body ΛDDM model is able to reduce theS8tension without convincingly solving it.
The GAPS Programme at TNG
Authors: Ruggieri A. , Desidera S. , Biazzo K. , Pinamonti M. , Marzari F. , Mantovan G. , Sozzetti A. , Bonomo A. S. , Lanza A. F. , Malavolta L. , Claudi R. , Damasso M. , Gratton R. , Nardiello D. , Benatti S. , Bignamini A. , Andreuzzi G. , Borsa F. , Cabona L. , Knapic C. , Molinari E. , Pino L. , Zingales T.
Published: January 2024

Context. Planets in binary systems are a fascinating and yet poorly understood phenomenon. Since there are only a few known large-separation systems in which both components host planets, characterizing them is a key target for planetary science.

Aims. In this paper, we aim to carry out an exhaustive analysis of the interesting XO-2 system, where one component (XO-2N) appears to be a system with only one planet, while the other (XO-2S) has at least three planets.

Methods. Over the last 9 yr, we have collected 39 spectra of XO-2N and 106 spectra of XO-2S with the High Accuracy Radial velocity Planet Searcher for the Northern emisphere (HARPS-N) in the framework of the Global Architecture of Planetary Systems (GAPS) project, from which we derived precise radial velocity (RV) and activity indicator measurements. Additional spectroscopic data from the High Resolution Echelle Spectrometer (HIRES) and from the High Dispersion Spectrograph (HDS), and the older HARPS-N data presented in previous papers, have also been used to increase the total time span. We also used photometric data from TESS to search for potential transits that have not been detected yet. For our analysis, we mainly used PyORBIT, an advanced Python tool for the Bayesian analysis of RVs, activity indicators, and light curves.

Results. We found evidence for an additional long-period planet around XO-2S and characterized the activity cycle likely responsible for the long-term RV trend noticed for XO-2N. The new candidate is an example of a Jovian analog with m sin i ~ 3.7 MJ, a ~ 5.5 au, and e = 0.09. We also analyzed the stability and detection limits to get some hints about the possible presence of additional planets. Our results show that the planetary system of XO-2S is at least one order of magnitude more massive than that of XO-2N. The implications of these findings for the interpretation of the previously known abundance difference between components are also discussed.
The globular cluster VVV CL002 falling down to the hazardous Galactic centre
Authors: Minniti Dante , Matsunaga Noriyuki , Fernández-Trincado José G. , Otsubo Shogo , Sarugaku Yuki , Takeuchi Tomomi , Katoh Haruki , Hamano Satoshi , Ikeda Yuji , Kawakita Hideyo , Lucas Philip W. , Smith Leigh C. , Petralia Ilaria , Rita Garro Elisa , Saito Roberto K. , Alonso-García Javier , Gómez Matías , Gabriela Navarro María
Published: January 2024

Context. The Galactic centre is hazardous for stellar clusters because of the strong tidal force in action there. It is believed that many clusters were destroyed there and contributed stars to the crowded stellar field of the bulge and the nuclear stellar cluster. However, the development of a realistic model to predict the long-term evolution of the complex inner Galaxy has proven difficult, and observations of surviving clusters in the central region would provide crucial insights into destruction processes.

Aims. Among the known Galactic globular clusters, VVV CL002 is the closest to the centre, at 0.4 kpc, but has a very high transverse velocity of 400 km s−1. The nature of this cluster and its impact on Galactic astronomy need to be addressed with spectroscopic follow up.

Methods. Here we report the first measurements of its radial velocity and chemical abundance based on near-infrared high-resolution spectroscopy.

Results. We find that this cluster has a counter-rotating orbit constrained within 1.0 kpc of the centre, and as close as 0.2 kpc at the perigalacticon, confirming that the cluster is not a passerby from the halo but a genuine survivor enduring the harsh conditions of the tidal forces of the Galactic mill. In addition, its metallicity and α abundance ([α/Fe] ≃ +0.4 and [Fe/H] = −0.54) are similar to those of some globular clusters in the bulge. Recent studies suggest that stars with such α-enhanced stars were more common at 3–6 kpc from the centre around 10 Gyr ago.

Conclusions. We infer that VVV CL002 was formed outside but is currently falling down to the centre, showcasing a real-time event that must have occurred to many clusters a long time ago.
Analysis of the public HARPS/ESO spectroscopic archive
Authors: Perdelwitz V. , Trifonov T. , Teklu J. T. , Sreenivas K. R. , Tal-Or L.
Published: January 2024

Context. Magnetic activity is currently the primary limiting factor in radial velocity (RV) exoplanet searches. Even inactive stars, such as the Sun, exhibit RV jitter of the order of a few m s−1 due to active regions on their surfaces. Time series of chromospheric activity indicators, such as the Ca II H&K lines, can be utilized to reduce the impact of such activity phenomena on exoplanet search programmes. In addition, the identification and correction of instrumental effects can improve the precision of RV exoplanet surveys.

Aims. We aim to update the HARPS -RVBANK RV database and include an additional 3.5 yr of time series and Ca II H&K lines (R′HK) chromospheric activity indicators. This additional data will aid in the analysis of the impact of stellar magnetic activity on the RV time series obtained with the HARPS instrument. Our updated database aims to provide a valuable resource for the exoplanet community in understanding and mitigating the effects of such stellar magnetic activity on RV measurements.

Methods. The new HARPS-RVBANK database includes all stellar spectra obtained with the HARPS instrument prior to January 2022. The RVs corrected for small but significant nightly zero-point variations were calculated using an established method. The R′HK estimates were determined from both individual spectra and co-added template spectra with the use of model atmospheres. As input for our derivation of R′HK, we derived stellar parameters from co-added, high signal-to-noise ratio templates for a total of 3230 stars using the stellar parameter code SPECIES.

Results. The new version of the HARPS RV database has a total of 252 615 RVs of 5239 stars. Of these, 195 387 have R′HK values, which corresponds to 77% of all publicly available HARPS spectra. Currently, this is the largest public database of high-precision (down to ~1 m s−1) RVs, and the largest compilation of R′HK measurements. We also derived lower limits for the RV jitter of F-, G-, and K-type stars as a function of R′HK.
The enigmatic dance of the HD 189733A system: A quest for accretion
Authors: Colombo S. , Pillitteri I. , Petralia A. , Orlando S. , Micela G.
Published: January 2024

Context. Several studies suggest that the emission properties of a star can be significantly affected by its interaction with a nearby planet through magnetic fields or interaction between their respective winds. However, the actual observability of these effects remains a subject of debate. An illustrative example is the HD 189733A system: certain characteristics of its emissions have been interpreted as indicative of ongoing interactions between the star and its associated planet. Other studies attribute these characteristics to the coronal activity of the star.

Aims. In this study we aimed to investigate whether the observed stellar X-ray flare events, which appear to be in phase with the planetary period in the HD 189733A system, could be attributed to the accretion of the planetary wind onto the stellar surface or if they resulted from an interaction between the planetary and stellar winds.

Methods. We developed a 3D magnetohydrodynamic model with the PLUTO code that describes the system HD 189733A , including the central host star and its hot Jupiter along with their respective winds. The effects of gravity and the magnetic fields of both the star and the planet are taken into account.

Results. Our analysis reveals that, in the cases examined in this study, the accretion scenario is only viable when the stellar magnetic field strength is at 5 G and the planetary magnetic field strength is at 1 G. In this scenario, the Rayleigh-Taylor instabilities lead to the formation of an accretion column that connects the star to the planet. Once formed the accretion column remains stable for the duration of the simulation. The accretion column produces an accretion rate of the order of 1012 g s−1 and shows an average density of about 107 cm−3. In the other case explored, the accretion column does not form because the Rayleigh-Taylor instability is suppressed by the stronger magnetic field intensities assumed for both the star and the planet. We synthesized the emission resulting from the shocked planetary wind and found that the total X-ray emission ranges from 5 × 1023 to 1024 erg s−1.

Conclusions. In the case of accretion, the emission originating from the hotspot cannot be distinguished from the coronal activity. Also, the interaction between the planetary and stellar winds cannot be responsible for the X-ray emission, as the total emission produced is about four orders of magnitude lower than the average X-ray luminosity of the star.