bluuebunny/crossref_metadata_2025 huggingface dataset:
Catching the wisps: Stellar mass-loss limits from low-frequency radio observations
Authors: Bloot S. , Vedantham H. K. , Kavanagh R. D. , Callingham J. R. , Pope B. J. S.
Published: February 2025

The winds of low-mass stars carry away angular momentum and impact the atmospheres of surrounding planets. Determining the properties of these winds is necessary to understand the mass-loss history of the star and the evolution of exoplanetary atmospheres. Due to their tenuous nature, the winds of low-mass main-sequence stars are difficult to detect. The few existing techniques for measuring these winds are indirect, with the most common inference method for winds of low-mass stars being astrospheric Lyman-α absorption combined with complex hydrodynamical modelling of the interaction between the stellar wind and the interstellar medium. Here, we employ a more direct method to place upper limits on the mass-loss rates of low-mass stars by combining observations of low-frequency coherent radio emission, the lack of free-free absorption, and a simple stellar wind model. We determine upper limits on the mass-loss rate for a sample of 19 M,dwarf stars detected with the LOFAR telescope at 120--168,MHz, reaching a sensitivity within an order of magnitude of the solar mass-loss rate for cold stars with a surface magnetic field strength of ∼100,G. The sensitivity of our method does not depend on distance or spectral type, allowing us to find mass-loss rate constraints for stars up to spectral type M6 and out to a distance of 50,pc, later and farther than previous measurements. With upcoming low-frequency surveys with both LOFAR and the Square Kilometre Array, the number of stars with mass-loss rate upper limits determined with this method could reach ∼1000.
The variability of DDO68-V1, a unique, extremely metal-poor luminous blue variable
Authors: Pustilnik S.A. , Perepelitsyna Y.A.
Published: February 2025

DDO68-V1 is a luminous blue variable (LBV) star in the eXtremely Metal-Poor (XMP) galaxy DDO68. It resides in the region with 12+log(O/H) ∼ 7.1 dex, or Z ∼ Z Since DDO68-V1 is the only known LBV with such a low initial metallicity, its in-deep study can give hints for understanding the LBV evolutionary stage and the nature of their powerful and highly variable mass loss in the very low-metallicity regime. Our goal is to study the optical variability of DDO68-V1 during the last 36 years, with an emphasis on the period of the last 8 years, after the LBV giant eruption. We used our published monitoring results in the B, V, and R bands of the total flux of region 'Knot 3', containing the LBV, along with photometry of the archive Hubble Space Telescope images, obtained in May 2010 and December 2017. This data allowed us to disentangle the variable light of DDO68-V1 and that of the underlying region. From all available photometry of Knot 3, we derived the V-band light curve of DDO68-V1 since 1988, with a higher cadence during the years 2015--2023, when the light curve resembles that of S Doradus. The new data reveal the full range of DDO68-V1 absolute magnitudes M_ V of mag. The LBV variations after the fading of the 'giant eruption' show the unusually large amplitude of δ V ≳ 3.0--3.5 mag on the timescale of ∼1--1.5 year. The apparent changes of the integrated B-V colour of Knot 3 are consistent with the expected colour variations of the LBV over the course of the S Doradus 'normal eruptions'. These data, along with spectra of DDO68-V1, demonstrate the need for a higher-cadence photometry of DDO68-V1, in order to probe the possible periodicity in its light curve and binarity of the object. Such data, in turn, will stimulate the elaboration of the advanced models of the very metal-poor massive stars and their application to the study of the early Universe.
Water in Ryugu as a property of processes in its parent body
Authors: Le Pivert-Jolivet T. , Brunetto R. , Pilorget C. , Baklouti D. , Bibring J.-P. , Carter J. , Hamm V. , Hatakeda K. , Jiang T. , Lantz C. , Loizeau D. , Mahlke M. , Nakato A. , Okada T. , Riu L. , Usui T. , Yada T. , Yogata K. , De León J. , Hitomi Y. , Kumagai K. , Licandro J. , Myazaki A. , Nagashima K. , Nakano A. , Nishimura M. , Ojima T. , Sugiyama Y. , Tahara R. , Saiki T. , Tanaka S. , Watanabe S. , Tsuda Y.
Published: February 2025

Samples from the asteroid Ryugu provide key information on the initial composition and evolutionary processes of primitive bodies. This study aims to detect H2O spectral features associated with inter-layer water in a statistically significant number of Ryugu grains protected from terrestrial contamination. We analysed hyperspectral data of millimetre-sized Ryugu grains (1.5–5.7 mm) obtained using the MicrOmega instrument at the Curation Facility. Water signatures were identified by computing the spectral distance from a reference Ryugu grain that exhibits a prominent 3 µm feature, which is associated with the presence of H2O We detect rare and small water-rich regions (typically $< 90 µ m^2). No significant difference in water content is observed between grains collected from chamber A (surface collection) and chamber C (artificial crater ejecta). The water-rich regions exhibit band widths similar to those of several primitive asteroids measured by the AKARI survey, whereas the average, millimetre-scale spectra of Ryugu grains show narrower bands. We confirm the low abundance of inter-layer water in Ryugu samples across a statistically significant number of grains. The spectral differences between Ryugu and the primitive asteroids analysed in this study reflect differences in composition that may indicate distinct formation reservoirs or evolutionary processes.
Detailed seismic study of Gemma (KIC11026764) using EGGMiMoSA. Unveiling the probing potential of mixed modes for subgiant stars
Authors: Farnir M. , Dupret M.-A. , Buldgen G.
Published: February 2025

When leaving the main sequence (MS) for the red-giant branch (RGB), subgiant stars undergo fast structural changes. Consequently, their observed oscillation spectra mirror these changes, constituting key tracers of stellar structure and evolution. However, the complexity of their spectra makes their modelling an arduous task, which few authors have undertaken. Gemma (KIC11026764) is a young subgiant with $45$ precise oscillation modes observed with Kepler, making it the ideal benchmark for seismic modelling. This study is aimed at modelling the subgiant Gemma, taking advantage of most of the precise seismic information available. This approach enables us to pave the way for the seismic modelling of evolved solar-like stars and provide the relevant insights into their structural evolution. Using our Levenberg-Marquardt stellar modelling tool, we built a family of models representative of Gemma's measured seismic indicators obtained via our seismic tool, EGGMiMoSA. We studied the structural information these indicators hold by carefully varying stellar parameters. We also complemented the characterisation with information held by indicators and non-seismic data. From the extensive set of models we built and using most of the seismic information at hand, including two ell=1 and one ell=2 mixed modes, we were able to probe the chemical transition at the hydrogen-burning shell. Indeed, we have demonstrated that among our models, only the ones with the sharpest chemical gradient are able to reproduce all the seismic information considered. One possibility to account for such a gradient is the inclusion of a significant amount of overshooting, namely α_ ov =0.17, which is unexpected for low-mass stars such as Gemma (expected mass of about $1.15 M_ ⊙
The dynamics of small-scale magnetic fields modulated by the solar cycle
Authors: Stangalini M. , Verth G. , Fedun V. , Perrone D. , Berretti M. , Bushby P. , Jafarzadeh S. , Jess D.B. , Giannattasio F. , Keys P.H. , Bruno R. , Berrilli F.
Published: February 2025

In addition to sunspots, the most easily visualized manifestation of solar magnetism, cutting-edge observations of the solar atmosphere have uncovered a plethora of magnetic flux tubes, down to the resolving power of modern high-resolution telescopes (a few tens of kilometers), revealing how the Sun is a fully magnetized star. These magnetic elements are advected and buffeted by ambient plasma flows and turbulent convection, resulting in perturbations of the flux tubes that make them natural conduits for channeling wave energy into the upper layers of the Sun’s atmosphere and significantly contributing to the acceleration of the solar wind. Data acquired by the Helioseismic and Magnetic Imager (HMI) on board NASA's Solar Dynamics Observatory (SDO) have made it possible to study the dynamics of small-scale magnetic fields over long timescales. Here, for the first time, we present the discovery of a modulation in the dynamical behavior of small-scale magnetic concentrations in the photosphere over temporal scales consistent with the solar activity cycle (i.e., $11$ years), which has only been made possible by the long observing lifetime of the SDO/HMI spacecraft. Furthermore, we also find a temporal varying polarization of their perturbations on similar timescales. This demonstrates how the small-scale dynamics of magnetic fields are also affected by the global dynamo. These discoveries were realized through automated tracking of magnetic fields in the solar photosphere over $11$ continuous years, resulting in the most extended statistical analysis of its kind so far, with more than $31$ million magnetic concentrations examined.
Time evolution of Mg II in SDSS J2320+0024: Implications for a subparsec binary supermassive black hole system
Authors: Fatović Marta , Ilić Dragana , Kovačević Andjelka B. , Palaversa Lovro , Simić Saša , Popović Luka Č. , Thanjavur Karun , Razim Oleksandra , Ivezić Željko , Yue Minghao , Fan Xiaohui
Published: February 2025

We present results from our spectroscopic follow-up of SDSS J2320+0024, a candidate binary supermassive black hole (SMBH) with a suspected subparsec separation, identified by a 278-day periodicity observed in its multiband optical light curves. Such systems serve as a crucial link between binaries with long periods (tens of years), which are influenced by tidal forces with minimal gravitational wave damping, and ultra-short-period binaries (≤ order of days), which are dominated by gravitational wave-driven inspiral. We investigated the dramatic variability in the complex emission line profile with the aim of testing the alignments of the observed photometric light curves and the spectroscopic signatures in the context of the binary SMBH system. We extracted the pure broad line from newly obtained Gemini and Magellan spectra and measured the emission line parameters to determine the fundamental dynamical parameters of the SMBH's binary system. We adopted the PoSKI subparsec binary SMBH model, which includes a broad-line region around a less massive component and a circumbinary broad-line region, to interpret the observed variability in the spectral profile. We find that the broad-line profile has a distinctive complex shape, with asymmetry and two peaks, which has varied across recent and archival observations. The temporal variability of the line profile may be associated with emission from the binary SMBH system, whose components have masses ( M_1 = 2 ⊙ ) and ( M_2 = 2 ⊙ ) and eccentricity e = 0.1. We discuss other plausible physical interpretations. With a total estimated mass of ∼ 10^9 ⊙ and a sub-annual orbital period, this system may be a rare example of a high-mass compact SMBH binary candidate and, thus, should be part of further investigations of the evolution of binary systems. This study highlights the synergies between spectroscopic follow-up and future massive time-domain photometric surveys, such as the Vera C. Rubin Observatory Legacy Survey of Space and Time.
Polarization sensitive Multi-band and wideband Ectromagnetically Induced Transparency -Like on Metamaterials
Authors: Ning Renxia , Zhao Ziyang , Ge Xue , He Ningye
Published: February 2025

In this paper, we study a metamaterial structure with multi-band and wideband EIT-like effect. Through the finite integration time domain method, the multi-band EIT-like structure was obtained by coupling two bright modes to two dark modes on transverse magnetic (TM) wave. And wideband EIT effect was studied on transverse electric (TE) wave by bright-bright mode coupled. The influence of the structural parameters of the structure on the transmission is analyzed. The performance index Q and sensitivity of the structure in the sensing domain are discussed. By comparison of theoretical calculation and experimental test results, the result in microwave band is basically match. The results show that the structure has potential applications in refractive index sensing and multiband filters.
Consumer perceptions and purchasing behavior of sustainable insurance products
Authors: Jahnert Jonas R. , Schmeiser Hato , Zehnle Meike
Published: February 2025

Insurers are beginning to change their business practices and add sustainable attributes to their insurance products. However, little is known about consumers’ reactions to such sustainable attributes in insurance contracts. In three surveys, of which the main study is incentive compatible, we investigate how sustainable attributes affect consumers’ purchase decisions and examine the mediating roles of trust, quality, brand image and perceived consumer effectiveness on purchase intentions. Our results provide converging evidence of a strong preference for sustainable insurance products. Surprisingly, this preference exists even at higher price levels. This can be explained by improved perceptions of the insurance company in terms of brand equity, product quality, and perceived consumer effectiveness.
Simultaneous observation of zero-index band and quasibound state in the continuum in all dielectric photonic crystals
Authors: Anwar Saad , Ahmed Shakeel , Riaz Muhammad Zeeshan , Asif Muhammad , Parveen Abida , Ouyang Zhengbiao
Published: February 2025

Zero-index (ZI) photonic materials show the absence of spatial phase accumulation, making them a suitable candidate for many useful optical applications. On the other hand, a bound state in the continuum (BIC), having extremely high-quality (Q) factors, provides a powerful way to enhance light–matter interaction, sensitivity, and nonlinear properties of materials. We propose a simple square lattice of silicon embedded in silica with C4v symmetry through which we achieved quasi-BIC with a high Q-factor of 2.25 × 107 and simultaneously obtained the zero-index band (ZIB) with a relative 3 dB bandwidth of 3.3%–3.66% through transmission–reflection consideration around the Dirac point. The experimental verification of the ZIB in the microwave band aligns well with the simulated results. An extension study and application in the THz band are also provided. The results can have potential applications in directive antennas, high-speed connectors and devices, sensors, non-linear optics, and large single-mode lasers with an appreciable band of operating frequency.
Conductive metal oxide and hafnium oxide bilayer resistive random-access memory: An ab initio study
Authors: Honet Antoine , Todri-Sanial Aida
Published: February 2025

We perform density functional theory simulations of interfaces between two conductive metal-oxides (CMOs, namely, TaO and TiO) and cubic hafnium oxide (HfO2) in the context of bilayer Resistive Random Access Memory devices. These simulations are made at the generalized gradient approximation level. We simulate filamentary conduction in HfO2 by creating an atomically thin O atom vacancy path inside HfO2. We show that this atomically thin filament leads to a great reduction in the resistance of the structures. Moreover, we explore the possibility of the influence of O excess inside the CMO on the global resistance of the device and confirm the induced modulation. We also shed the light on two possible causes for the observed increase in the resistance when O atoms are inserted inside the CMO. Eventually, we push forward the key differences between devices with TaO and TiO as CMO. We show that structures with TaO are more stable in general and lead to a behavior implying only low and high resistance (two well-separated levels) while structures with TiO allow for intermediate resistances.
Strong coupling of excitons in a two-dimensional atomic crystal with quasi-bound state in the continuum supported by a single nanoparticle
Authors: Ding Qi , Zhou Xun , Xie Peng , Shen Shiyu , Yue Ling , Zhang Hong , Wang Wei
Published: February 2025

Bound states in the continuum (BICs) supported by high-index dielectric nanoparticles have garnered significant attention due to their ability to achieve subwavelength confinement with high-quality factors, offering great potential for both fundamental studies of light–matter interactions and the development of compact photonic devices. However, the strong coupling of BICs with quantum emitters in single-particle systems has not been reported. In this paper, we propose a dielectric nanodisk integrated with a monolayer of transition metal dichalcogenides. A supercavity mode known as Friedrich–Wintgen BIC is launched in the nanodisk to enable strong coupling of BIC with WS2 excitons. We demonstrate that the reduction in coupling strength as the quasi-BIC quality factor increases is due to a decrease in the number of excitons participating in the coupling. Additionally, the coupling strength can be manipulated by adjusting the shape and aspect ratio of the nanoresonators, enabling a transition from strong to weak coupling regimes. Near-field analysis shows that the manipulation of the BIC–exciton interaction arises from the overlap of the BIC mode's near-field with the excitons. Our findings offer a promising strategy for manipulating light–matter interactions and enhance the potential applications of BIC resonances in photonics.
Modeling cross-beam energy transfer with sector ray tracing
Authors: Follett R. K. , Igumenshchev I. V. , Colaïtis A. , Palastro J. P. , Froula D. H. , Turnbull D.
Published: February 2025

Ray-based cross-beam energy transfer (CBET) models are an essential feature of the radiation-hydrodynamic codes used to simulate inertial confinement fusion implosions, but full 3D ray-based CBET calculations can have a prohibitively high computational cost. Sector ray tracing can be used to reduce the cost by orders of magnitude in cases where the coronal plasma and laser drive can be approximated as spherically symmetric. An extension of sector ray tracing (section ray tracing) can be used to relax the assumption of a spherically symmetric drive while still retaining most of the computational savings of a sector ray trace. We discuss the foundations of sector and section ray tracing and compare them to full ray tracing.
Ectopic mouse TMC1 and TMC2 alone form mechanosensitive channels that are potently modulated by TMIE
Authors: Chen Yixuan , Li Yulin , Liu Yonghong , Sun Jiawen , Feng Wanying , Chen Yanfei , Tian Ye , Lei Tianlun , Huang Pingbo
Published: February 2025

The mechanotransduction (MT) channel expressed in cochlear and vestibular hair cells converts the mechanical stimulation of sound and head movements into electrochemical signals. Recently, TMC1 and TMC2 (TMC1/2) have been recognized as the pore-forming subunit of the MT channel, but TMC1/2 functional expression in heterologous cells—which is critical for unequivocally identifying them as the bona fide pore-forming subunit of the MT channel—has not been achieved because ectopic TMC1/2 become trapped in the ER. Here, we report that adding a Fyn lipidation tag to mouse TMC1/2 (mTMC1/2) drove their cell-surface expression, and, importantly, full-length mTMC1/2 expressed alone functioned as mechanosensitive channels, underscoring the view that TMC1/2 constitute the sole pore-forming subunit of the MT channel. Moreover, mouse transmembrane inner ear (TMIE) (mTMIE) protein robustly stimulated TMC1/2 channel activity by modulating their gating. Intriguingly, the N-terminal 27 residues of mTMIE were dispensable for regulating TMC1/2 in our in vitro functional assay, whereas, in striking contrast, mutating mTMIE C76C77, the predicted palmitoylation sites, eliminated mTMIE stimulation of mTMC1/2, indicating a crucial role of the palmitoyl group in regulating TMC1/2 gating. mTMC1/2+mTMIE form 18 pS and 24 pS single channels, respectively. mTMC1/2+mTMIE single channels showed biophysical and pharmacological properties similar to those of the MT channel. Our findings provide insights into several fundamental and debated aspects of the function of TMC1/2 and TMIE, and our functional assay of TMC1/2 and TMIE in heterologous cells will facilitate further functional and structural characterization of these proteins and other MT-complex components.
Emergent quantum state unveiled by ultrafast collective dynamics in 1
T
-TaS
2
Authors: Hasaien Jiazila , Wu Yanling , Shi Mengzhu , Zhai Yanni , Wu Qiong , Liu Zheng , Zhou Yi , Chen Xianhui , Zhao Jimin
Published: February 2025

Charge density wave (CDW) material 1
T
-TaS
2
was proposed as a quantum spin liquid candidate, on which a cluster Mott insulator comes into being below the transition temperature. We report an experimental ultrafast generation and detection of the coherent amplitude mode (AM) of its CDW state. A salient feature emerges: The coherent CDW mode AM exhibits an unusual
T
3.56
temperature dependence below 65 K, in addition to the
T
2
temperature dependence observed in the 65 to 200 K range. This behavior suggests the enhancement of in-gap electronic excitations below 65 K and the emergence of a new phase of matter. Consequently, the intriguing quantum state leads to a crossover. Our investigation provides insights into understanding the interplay among various degrees of freedom in quantum materials.
Innovation in ant larval feeding facilitated queen–worker divergence and social complexity
Authors: Matte Arthur , LeBoeuf Adria C.
Published: February 2025

Building differences between genetically equivalent units is a fundamental challenge for all multicellular organisms and superorganisms. In ants, reproductive or worker fate is typically determined during the larval stage, through feeding regimes managed by adult caretakers. However, the feeding care provided to larvae varies significantly across ants, as does phenotypic divergence between queen and worker castes. Here, we employed comparative phylogenetic methods and causal inference to investigate the relationships between larval feeding care, caste size dimorphism, and social complexity across ant diversity. We digitized the life’s work of George and Jeanette Wheeler, cataloging the larval morphology of over 700 species, and we compiled data on species diets and larval feeding behaviors from the literature and our own observations. We measured queen–worker size dimorphism in 392 species and gathered data for colony size, worker polymorphism, and worker reproduction. Our analyses revealed that ancestral active-feeding larvae evolved passive morphologies when adults began feeding them individually, typically with processed material and often following a shift to nonpredatory diets. Greater queen–worker size dimorphism coevolved with larval passiveness, alongside traits indicative of increased social complexity, including larger colony sizes, worker subcastes, and a reduction in workers’ reproductive potential. Likelihood comparisons of causal phylogenetic models support that extended alloparental care facilitated stronger caste dimorphism, which, in turn and along with increased colony sizes, promoted higher social complexity. Our results suggest that enhanced adult control over larval development enabled greater phenotypic specialization within colonies, with profound implications for social evolution.
NOTCH, ERK, and SHH signaling respectively control the fate determination of cortical glia and olfactory bulb interneurons
Authors: Gao Yanjing , Sun Mengge , Fu Tongye , Wang Ziwu , Jiang Xin , Yang Lin , Liang Xiaoyi G. , Liu Guoping , Tian Yu , Yang Feihong , Li Jialin , Li Zhenmeiyu , Li Xiaosu , You Yan , Ding Chaoqiong , Wang Yuan , Ma Tong , Zhang Zhuangzhi , Xu Zhejun , Chen Bin , Yang Zhengang
Published: February 2025

During cortical development, radial glial cells (neural stem cells) initially are neurogenic, generating intermediate progenitor cells that exclusively produce glutamatergic pyramidal neurons. Next, radial glial cells generate tripotential intermediate progenitor cells (Tri-IPCs) that give rise to cortical astrocytes and oligodendrocytes, and olfactory bulb interneurons. The molecular mechanisms underlying the transition from cortical neurogenesis to gliogenesis, and the subsequent fate determination of cortical astrocytes, oligodendrocytes, and olfactory bulb interneurons, remain unclear. Here, we report that extracellular signal-regulated kinase (ERK) signaling plays a fundamental role in promoting cortical gliogenesis and the generation of Tri-IPCs. Additionally, sonic hedgehog-smoothened-glioma-associated oncogene homolog (SHH-SMO-GLI) activator signaling has an auxiliary function to ERK during these processes. We further demonstrate that, from Tri-IPCs, NOTCH signaling is crucial for the fate determination of astrocytes, while ERK signaling plays a prominent role in oligodendrocyte fate specification, and SHH signaling is required for the fate determination of olfactory bulb interneurons. We provide evidence suggesting that this mechanism is conserved in both mice and humans. Finally, we propose a unifying principle of mammalian cortical gliogenesis.
Van der Waals quantum dots on layered hexagonal boron nitride
Authors: Wu Yuanpeng , Xiao Yixin , Zhao Ying , Shen Yifan , Sun Kai , Wang Boyu , Wang Ping , Wang Ding , Zhou Peng , Wang Danhao , Liu Jiangnan , Hu Mingtao , B. Norris Theodore , Song Jun , Mi Zetian
Published: February 2025

Semiconductor quantum dots (QD) promise unique electronic, optical, and chemical properties, which can be exquisitely tuned by controlling the composition, size, and morphology. Semiconductor QDs have been synthesized primarily via two approaches, namely, epitaxial growth and wet-chemical synthesis. However, the properties of epitaxial QDs (eQDs) are susceptible to wetting layer formation and substrate dislocations, while colloidal QDs (cQDs) face fluorescence intermittency issues. Here, we report on the synthesis of a class of QDs that can overcome the fundamental limitations of eQDs and cQDs. By exploiting the sp
2
bonding of layered hexagonal boron nitride (hBN), we show that GaN QDs can be epitaxially grown through a weak van der Waals (vdW) interaction without two-dimensional wetting layer formation. The photoluminescence intensity of GaN van der Waals quantum dots (vQDs) is more than six times stronger than that of conventional GaN eQDs and no optical blinking was observed from vQDs. We show that the interadatom bond strength is about one order of magnitude stronger compared with that between the adatoms and the hBN substrate. This work shows that vQDs have unique properties that are difficult to achieve using existing QDs synthesis methods and thus can potentially enable new classes of high-performance optoelectronic and quantum devices.
O-GalNAc glycans are enriched in neuronal tracts and regulate nodes of Ranvier
Authors: Noel Maxence , Suttapitugsakul Suttipong , Cummings Richard D. , Mealer Robert G.
Published: February 2025

Protein O-glycosylation is a critical modification in the brain, as genetic variants in the pathway are associated with common and severe neuropsychiatric phenotypes. However, little is known about the most abundant O-glycans in the mammalian brain, which are N-acetylgalactosamine (O-GalNAc) linked. Here, we determined the spatial localization, protein carriers, and cellular function of O-GalNAc glycans in the mouse brain. We observed striking spatial enrichment of O-GalNAc glycans in neuronal tracts, and specifically at nodes of Ranvier, specialized structures involved in signal propagation in the brain. Glycoproteomic analysis revealed that more than half of the identified O-GalNAc glycans were present on chondroitin sulfate proteoglycans termed lecticans, and display both domain enrichment and regional heterogeneity. Inhibition of O-GalNAc synthesis in neurons reduced binding of Siglec-4, a known regulator of neurite growth, and shortened the length of nodes of Ranvier. This work establishes a function of O-GalNAc glycans in the brain and will inform future studies on their role in development and disease.
Chiral structural color from microdomes
Authors: Lai Xintao , Li Tongyu , Hou Xiaoyu , Vogelbacher Florian , Wang Jiajun , Song Yanlin , Shi Lei , Li Mingzhu
Published: February 2025

Artificial chiral-structural-color materials can carry high-dimensional information based on multiple optical degrees of freedom, providing possibilities for advanced optical security and information storage. However, current artificial chiral-structural-color materials are hindered by their specific compositions, fine nanostructures, and single polarization modulation. Here, we found that microdomes made from common polymers have chiral structural colors with broadband tunability and multiple polarization-modulated chirality. The microdome patterns are easily fabricated by ordinary printing techniques and have inhomogeneous spatial distributions of full polarization states and customizable colors. Our chiral-structural-color microdomes (CSCMs) provide a promising roadmap for high-capacity information encryption and high-security anti-counterfeiting. We developed multidimensional tunable structural color displays and achieved encryption with high information capacity. To further highlight the application potential, we constructed contact lenses integrated with CSCMs for identity authentication with 2
32
distinctive cryptograms.
Empowering genome-wide association studies via a visualizable test based on the regional association score
Authors: Jiang Yiran , Zhang Heping
Published: February 2025

The genome-wide association studies identified genes associated with many diseases, but the identification and verification of disease variants are still challenging due to small effects and large number of individual variants. In this paper, we propose a powerful method that first quantifies the strength of regional associations at each single nucleotide polymorphism and converts these measures into time series data before using a change point detection algorithm to identify significant regions. In our extensive simulation study, the proposed method consistently demonstrates greater power than existing alternatives, achieving a relative increase of over 20% in challenging scenarios where true causal variants are sparse and multiple association regions exist at the same time, while maintaining a lower false positive rate.
pTDP-43 levels correlate with cell type–specific molecular alterations in the prefrontal cortex of
C9orf72
ALS/FTD patients
Authors: Wang Hsiao-Lin V. , Xiang Jian-Feng , Yuan Chenyang , Veire Austin M. , Gendron Tania F. , Murray Melissa E. , Tansey Malú G. , Hu Jian , Gearing Marla , Glass Jonathan D. , Jin Peng , Corces Victor G. , McEachin Zachary T.
Published: February 2025

Repeat expansions in the
C9orf72
gene are the most common genetic cause of amyotrophic lateral sclerosis and familial frontotemporal dementia (ALS/FTD). To identify molecular defects that take place in the dorsolateral frontal cortex of patients with
C9orf72
ALS/FTD, we compared healthy controls with
C9orf72
ALS/FTD donor samples staged based on the levels of cortical phosphorylated TAR DNA binding protein (pTDP-43), a neuropathological hallmark of disease progression. We identified distinct molecular changes in different cell types that take place during FTD development. Loss of neurosurveillance microglia and activation of the complement cascade take place early, when pTDP-43 aggregates are absent or very low, and become more pronounced in late stages, suggesting an initial involvement of microglia in disease progression. Reduction of layer 2-3 cortical projection neurons with high expression of CUX2/LAMP5 also occurs early, and the reduction becomes more pronounced as pTDP-43 accumulates. Several unique features were observed only in samples with high levels of pTDP-43, including global alteration of chromatin accessibility in oligodendrocytes, microglia, and astrocytes; higher ratios of premature oligodendrocytes; increased levels of the noncoding RNA NEAT1 in astrocytes and neurons, and higher amount of phosphorylated ribosomal protein S6. Our findings reveal progressive functional changes in major cell types found in the prefrontal cortex of
C9orf72
ALS/FTD patients that shed light on the mechanisms underlying the pathology of this disease.
Word processing through lexical decision in Brazilian Portuguese
Authors: Estivalet Gustavo , Ferrari-Neto José , Minussi Rafael , Villalva Alina
Published: February 2025

This study investigates word processing in Brazilian Portuguese, focusing on blends, which juxtapose or overlap
(W)ords and/or (C)lips (e.g. portunhol = (portu)guês ‘Portuguese’ + espa(nhol)
‘Spanish’). Blends present intriguing theoretical and empirical challenges to models of morphological analysis, morphological
processing, lexical access, and the mental lexicon. Most research on blends has been conducted in languages other than Portuguese.
This study addresses this gap by exploring the processing of blends in Brazilian Portuguese through a behavioral lexical decision
experiment. We manipulated blends in constituent structure and grammatical structure, considering (H)ead and (M)odification.
Additionally, we compared blends against words with various morphological structures, such as derived complex words containing
prefixes (e.g., [des]acordo ‘disagreement’) or suffixes (e.g., cozinh[eiro] ‘cook’), and
monomorphemic simplex words. We also included simplex and complex pseudowords (e.g., [acont]arago;
dador[eiro]) and nonwords (e.g., sfaricrelj) in the experiment. Accuracy and reaction time
results suggest that blends are accepted and processed differently from simplex and complex words, resembling pseudowords. This
study contributes to a deeper understanding of blend description and processing, providing valuable insights into lexical access,
enhancing theoretical and empirical comprehension of morphological processing.
Time-resolved measurements of the E-H transition in a microwave driven ICP source
Authors: Porteanu Horia-Eugen Eugen , Stefanovic Ilija , Klute Michael , Awakowicz Peter , Brinkmann Ralf Peter , Heinrich Wolfgang
Published: February 2025

The transition dynamics from the electrostatic to electromagnetic (E-H) coupling in a 2.45 GHz excited inductivelycoupled plasma (ICP) source is investigated using a set of microwave time-resolved records at different frequencies.This method, coming from semiconductor physics, has been newly adapted for plasma investigations. Nitrogen andoxygen plasmas have been analyzed in the range 20 - 1000 Pa with a constant excitation power of 40 W. With aresolution better than 100 ns, one can identify, depending on pressure, the coexistence of the E and H modes, a hybridEH mode, and, in the case of oxygen plasma, the transition from negative to positive ions. The E-H transition timeincreases with pressure.
Room Temperature RF-Sputtered Cu2O Thin Films: A Promising Hole Transport Layer for Antimony Chalcogenide Solar Cells.
Authors: Mijangos-Alonzo Pedro , Vigil-Galán Osvaldo , Acosta Milenis , Hernández Castillo R. , Nicolás Marín Miriam Marmara , RIECH INES
Published: February 2025

In this work, Cu2O thin films were deposited on glass by reactive sputtering at room temperature, varying the sputtering power and the oxygen partial pressure in the chamber. The thin films' electrical resistivity, optical, morphological, and structural properties were studied, and the results are presented and discussed. Single-phase Cu2O thin films were optimized using 120 W sputtering power and 0.7x10-6 bar of oxygen partial pressure. These deposition conditions were used to prepare copper oxide thin films onto an Sb2(S,Se)3 layer. The resulting Cu2O with its low electrical resistivity (~10^1 Ω-cm), comparable to the lowest Cu2O values ​​obtained with different growth techniques, and its smooth and compact morphology, providesinsights into its potential use as a hole transport layer in Sb2(S,Se)3 solar cells.
Spatiotemporal chirped Laguerre complex-variable-function Gaussian wave packets in a strongly nonlocal nonlinear medium
Authors: Wang Rui , Liu Zhirong
Published: February 2025

Evolutionary of spatiotemporal chirped Laguerre complex-variable-function Gaussian (CLCG) wave packets in a strongly nonlocal nonlinear medium (SNNM) is investigated for the first time. Solution of the spatiotemporal CLCG wave packets in a SNNM is obtained by the separate variable method. Results demonstrate that the evolution properties of the targeted CLCG wave packets are dependent on the disparate distribution parameter and chirp parameter of the wave packets. The stabilities of the wave packets under different perturbation scenarios are further analyzed. In addition, the Poynting vector of the CLCG wave packets in propagation is investigated, and it shows that the direction of energy flow corresponds to the rotation of the wave packets. The effect of wave packet rotation on CLCG wave packet evolution is described. The gradient and scattering forces of the CLCG wave packet are also discussed. Finally, the nonlinearity of the CLCG wave packet and the energy transfer efficiency are discussed. Results obtained in this paper could provide a new idea for the modulation and control of multidimensional optical fields.
Non-locality in quadrupolar gravitational radiation
Authors: Capozziello S. , Capriolo M. , Carleo A. , Lambiase G.
Published: February 2025

General Relativity suffers for two main problems which have not yet been overcome: it predicts spacetime singularities and cannot be formulated as a perturbative renormalizable theory. In particular, many attempts have been made for avoiding singularities, such as considering higher order or infinite derivative theories. The price to pay in both cases is to give up locality and therefore they are known altogether as non-local theories of gravity. In this paper, we investigate how to recognize the presence of non-local effects by exploiting the power emitted by gravitational waves in a binary system in presence of non-local corrections as R□-1
R to the Hilbert-Einstein action. After solving the field equations in terms of the source stress-energy tensor T

μν
and obtaining the gravitational wave stress-energy pseudo-tensor, T

μν
, we find that the General Relativity quadrupole formula is modified in a non-trivial way, making it feasible to find a possible signature of non-locality. Our final results on the gravitational wave stress-energy pseudo-tensor could also be applied to several astrophysical scenarios involving energy or momentum loss, potentially providing multiple tests for non-local deviations from General Relativity. We finally discuss the detectability of the massless transverse scalar mode, discovering that, although this radiation is extremely weak, in a small range around the model divergence, its amplitude could fall within the low-frequency Einstein Telescope sensitivity.
SpectrAx: spectral search of axion-like particles using multi-band observations of galaxy clusters from SKA, SO, CMB-S4 and eROSITA
Authors: Mehta Harsh , Mukherjee Suvodip
Published: February 2025

The existence of axions or Axion-Like Particles (ALPs) has been predicted by various Beyond Standard Model (BSM) theories, and the proposed photon-ALP interaction is one of the ways to probe them. Such an interaction will lead to photon-ALP resonant conversion in galaxy clusters, resulting in a polarized spectral distortion in the CMB along the cluster line of sight. The estimation of this signal from galaxy clusters requires an estimation of their electron density and magnetic field profiles, as well as their redshifts. We have developed a new Bayesian framework SpectrAx that can use observations from different electromagnetic bands such as radio, CMB, optical, and X-ray to infer the astrophysical properties of a galaxy cluster, such as cluster its redshift, electron density and magnetic field, along with the BSM physics such as ALPs.
We use simulated redshifts in our analysis, but that can be obtained by cross-matching with optical surveys having overlapping sky regions with the galaxy clusters. Also, we use radial profiles that are motivated from observations of galaxy clusters at low redshifts. By using the simulated data corresponding to the ALP mass of 10-14 eV for upcoming CMB surveys such as Simons Observatory (SO) and CMB-S4 in combination with Square Kilometer Array (SKA) and extended ROentgen Survey with an Imaging Telescope Array (eROSITA) we demonstrate the capability in accurately inferring the ALPs coupling strength along with the radial profile of electron density and magnetic field from galaxy clusters. The application of this framework to the data from future surveys by combining SKA+SO+eROSITA and SKA+CMB-S4+eROSITA will make it possible for the first time to explore both astrophysics and BSM physics from low-redshift galaxy clusters using a multi-band approach.
Relaxing limits from Big Bang Nucleosynthesis on Heavy Neutral Leptons with axion-like particles
Authors: Deppisch Frank F. , Gonzalo Tomás E. , Majumdar Chayan , Zhang Zhong
Published: February 2025

Heavy neutral leptons (HNLs) are constrained by requirements of Big Bang Nucleosynthesis (BBN) as their decays significantly impact the formation of the primordial elements. We propose here a model where the primary decay channel for the HNLs is to an axion-like particle (ALP) and a neutrino. Consequently, HNLs can decay earlier and evade the BBN bound for lower masses, provided the ALPs themselves decay considerably later. Further cosmological and astrophysical constraints limit severely the range of validity of the ALP properties. We find that a new parameter region opens up for HNLs with masses between 1 MeV and 1 GeV, and active-sterile neutrino mixing strengths between 10-9 and 10-6 that is consistent with constraints and can be probed in future searches. In such a scenario, current bounds as well as sensitivities of future direct HNL searches such as at NA62 and DUNE will be affected.
Guiding and magneto-optical properties in TGG waveguide by proton implantation combined with femtosecond laser ablation
Authors: Liu Chun-Xiao , Wang Zi-Hao , Guo Bei-Er , Yuan Rui , Wang Yi-Fan , Zhou Yu-Hang , Sun Jia-Bin , Zhang Liao-Lin , Guo Hai-Tao
Published: February 2025

Integrating the magneto-optical effect into a waveguide-based photonic device becomes more and more interesting. In the work, the planar optical waveguide firstly was prepared in a TGG crystal via the proton implantation with the energy of 4×10-1 MeV and the fluence of 6×108 ions/μm2. Subsequently, a femtosecond laser with a central wavelength of 800 nm and a power of 3 mW was used to ablate the surface of the planar waveguide, forming the ridge optical waveguide. The dark-mode curve of the planar waveguide was measured by a prism coupling technique. The top-view morphology of the ridge waveguide was observed via a Nikon microscope. The mode field distributions of the planar and ridge waveguides were obtained by an end-face coupling system, and the propagation losses of the two waveguides were measured to be 2.26 dB/cm and 2.58 dB/cm, respectively. The Verdet constants were measured to be -72.7 °/·cm for the TGG substrate and -60.7 °/·cm for the ridge waveguide. The TGG waveguides have a potential in the fabrication of magneto-optical waveguide devices.
Detectability of Kilonovae from Binary Neutron Star Mergers through Electromagnetic Survey Telescopes
Authors: Zhao Chunyang , Lu Youjun , Zhao Wen
Published: February 2025

Mergers of binary neutron stars (BNSs) produce kilonovae, powered by decay of r-process heavy nuclei in their ejecta. Searching and finding kilonovae, associated with gravitational wave (GW) detected BNS mergers, is crucial for multimessenger studies of BNS mergers and their astrophysical and cosmological applications. In this paper, we investigate the detectability of kilonovae by several electromagnetic surveys, including SiTian, the Chinese Space Station Telescope (CSST), the Rubin Observatory, Euclid and the Nancy Grace Roman Space Telescope (RST). We consider BNS mergers detected by both the network of the Laser Interferometer Gravitational Wave Observatory (LIGO), Virgo and Kagra (LVK), and of the Einstein Telescope and Cosmic Explorer (ET\&2CE). We adopt a binary population synthesis model to obtain mock sample of BNS mergers with known properties, and a phenomenological kilonova model to predict multiband light curves of kilonova associated with each BNS merger. We predict the detection rate or efficiency of kilonovae by Rubin and SiTian, CSST, Euclid and RST, associated with BNS mergers either detected by LVK operation 5 (O5) or ET\&2CE, under either the wide fast deep survey or time of opportunity strategy. We also predict the parameter (total mass, mass ratio, localization area) distributions of BNS systems jointly detected by GW and EM observations. We emphasize that kilonovae associated with massive BNS mergers like GW\,190425 (with total mass $\gtrsim3.3M_\odot$) can be detected in a significant fraction $\simeq20-30$\% for ET\&2CE or $\simeq30-40$\% for LVK O5 by SiTian with a shallow observational depth or other survey telescopes, providing crucial information for kilonova physics and the equation of state of neutron stars.
Systematic review on visual aid technologies for surgical assistant robotic devices
Authors: Mendoza-Baustista Karen , Torres-Mendez Abril , Chairez Isaac
Published: February 2025

This review comprehensively analyzes the modern literature on including visual aids in diverse surgical assistant robotic systems. The review considered a deep analysis of diverse technical and scientiﬁc sources that provide precise information on how the more recent surgical systems, especially those considering robotic devices, perform automatic operations on patients. The search procedure and the corresponding analytics considered only those conditions where vision systems played a signiﬁcant role in the surgical procedure, despite the type of end-effector and if only position or force were used as part of the feedback analysis. This review is organized considering the robot conﬁguration, the type of end-effector, the vision systems considered for those cases, and the associated control actions, which must include the acquired image or video. The study analyzes the key contributions of the published cases. It provides a critical description of the advantages and shortcomings of the technological implementation of vision systems in surgical robotic devices. Finally, this review provides a general prospective view of ongoing research on vision aids for surgical robotic systems, which will become an ordinary actor in future surgical systems.Note for the practitioners: This review offers a technicaloriented analysis of modern robotic devices and their integration with automatic vision systems that could operate as efﬁcient surgical automatic systems. In particular, the review offers a systematic analysis that justiﬁes the introduction of visual aiding systems that may solve different tasks such as tracking trajectory, supervision, and prevention.