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We analyze the impact of specialist and generalist stars on organizational performance by linking the literature on star employees and specialization. Our adaptive role framework allows stars to switch roles over time. We develop a game-theoretical model to derive hypotheses and to empirically test them using basketball data. Consistent with theoretical predictions, the results show that teams with generalist stars outperform those with specialists. While a generalist switching to a specialist role always worsens performance, a specialist switching to a generalist role may improve performance. Additional estimations suggest that these findings hold for teams relying on a unique star rather than multiple stars.
The study of dense matter has been greatly advanced by progress in theoretical high-energy simulations and modern observational astronomy. Neutron stars serve as natural laboratories for probing matter under extreme density and strong gravitational fields. While polytropic equations of state are widely employed, conventional models based on a single polytropic index cannot adequately represent the stratified, layered nature of realistic compact-star interiors. To address this limitation, we develop a composite relativistic polytropic model in which the polytropic index varies smoothly with radius. By coupling the Einstein field equations with a generalized composite polytropic equation of state, we derive the composite Tolman-Oppenheimer-Volkoff (CTOV) system. The resulting nonlinear equations are solved using a Monte Carlo-based numerical integration method, which efficiently handles stiffness while enabling probabilistic exploration of the parameter space and natural uncertainty quantification. Our results demonstrate that increasing the relativistic parameter σ significantly reduces both the Emden function and the enclosed mass function, producing more compact stellar configurations. Sharper core-envelope transitions (ε = 0.01) yield systematically higher compactness than smoother transitions (ε = 0.03). The derived mass-radius relations reproduce the observed diversity of neutron stars, successfully matching both low-mass, large-radius systems such as PSR J0030 + 0451 and high-mass compact pulsars such as PSR J1614-2230. Importantly, the maximum-mass analysis shows that stiff composite configurations (nc = 1, ne = 2, xc = 0.7) can support gravitational masses up to Mmax ≈ 3.47 M[Formula: see text] for ε = 0.01 and Mmax ≈ 2.71 M[Formula: see text] for ε = 0.03, with corresponding minimum radii in the range Rmin ≈ 10.6-13.2 km, consistent with current observational constraints. These findings confirm that composite polytropes provide a flexible, physically motivated framework for modeling stratified compact stars and for constraining the dense-matter equation of state.
A central question in developmental biology is how organs acquire their final shape. Since a conserved organ might form through distinct steps, even within animals belonging to the same class, comparative studies are needed to reveal conserved or unique principles. Sea stars are a useful system to investigate how organs develop their specific structure across various species. This species-rich and diverse class of animals provide embryos that can be easily cultured in large numbers and are optically clear, which allows morphogenesis to be observed live. All sea star larvae develop a coelom: a hollow tube that fills the body cavity. We recently named it the "hydro-vascular organ" (HVO), as most of this organ will form the adult water-vascular system after metamorphosis. Understanding the distinct steps that drive HVO development across species requires comparative studies, but detailed characterizations of embryonic and larval stages have been reported for only a few representatives of asteroidea. Here we use brightfield microscopy and live imaging to document for the first time the development of Asterias forbesi, an ecologically important species that lacks a detailed description of embryonic and larval stages. Leveraging the optical clarity of these larvae, we defined distinct stages of HVO morphogenesis. To understand whether the same organ forms through shared steps across different species, we compare A. forbesi HVO development with sea stars from two other orders, Patiria minata and Astropecten aranciacus. The online version contains supplementary material available at 10.1007/s00427-026-00731-5.
The strong magnetic fields of neutron stars are closely linked to their observed thermal, spectral, and timing properties, such as the distribution of spin periods and their derivatives. To understand the evolution of astrophysical observables over time, it is essential to develop robust theoretical frameworks and numerical models that solve the coupled thermal and magnetic field evolution equations, incorporating detailed microphysics such as thermal and electrical conductivities and neutrino emission rates. These efforts are key to uncovering how the strength and geometry of magnetic fields change with age, ultimately shedding light on the diverse phenomenology of neutron stars. In this review, we outline the fundamental theory underlying magneto-thermal evolution models, with an emphasis on numerical methods and a comprehensive set of benchmark tests intended to guide current and future code development. We revisit established results from axisymmetric simulations, highlight recent progress in fully three-dimensional models, and offer a perspective on the anticipated developments in this rapidly evolving field. The online version contains supplementary material available at 10.1007/s41115-026-00028-4.
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The metal abundances in galactic nuclei carry key information on the history of star formation and mass transfer in central regions of galaxies. X-ray fluorescence analysis is a unique tool to reliably measure the abundances of various elements via simple physics. Here we present a new observation of the active nucleus in the Circinus galaxy with the XRISM satellite at unprecedented X-ray energy resolution. The fluorescent iron Kα line profile modified by Compton scattering indicates that the material responsible for its emission is cold and metal rich and is located ≳0.024 pc from the supermassive black hole, consistent with the dusty torus region. The abundance pattern derived from comparing fluorescent line intensities of different metals shows subsolar ratios of argon- and calcium-to-iron and a supersolar ratio of nickel-to-iron. This abundance pattern is best produced by a combination in number fraction of 9 2 - 4 + 2 % core-collapse supernovae from progenitor stars less massive than 2 0 - 2 + 3 M ⊙ and 8 - 2 + 4 % type Ia supernovae. This suggests that gas feeding the supermassive black hole was enriched by recent core-collapse supernovae. Our findings imply that in metal-rich environments stars more massive than about 20 M ⊙ directly collapse into black holes or make faint supernovae without ejecting heavy metals into the space.
Spatial neglect after stroke may be difficult to characterize in patients with severe motor, cognitive, and communication impairment. Augmentative and alternative communication interfaces require visual scanning and intentional selection and may therefore provide an ecological context in which lateralized visuospatial behavior becomes clinically observable. A 58-year-old man with a unilateral right-hemisphere hemorrhagic stroke underwent serial assessment at baseline before training, at the end of 24 AAC sessions delivered over 2 months in addition to standard neurorehabilitation, and at 1-month follow-up. Measures included cognitive functioning, behavioral responsiveness, global disability, bedside communication status, and P300 latency. The AAC/eye-tracking intervention also generated process data across 21 analyzable sessions, including calibration quality, free-exploration heatmaps, and performance in the Stars and Bow-Target tasks. Global measures showed modest early improvement followed by stabilization. Cognitive functioning improved from 2 to 3 and remained stable, behavioral responsiveness increased from 7 to 10 and then to 11, bedside communication increased from 7 to 9 and remained stable, and P300 latency decreased from 393 to 350 and then to 351 ms, whereas global disability remained unchanged at 25 throughout. Calibration was at least good in all quadrants and never scored 0. Performance was lower and more unstable in Stars than in Bow-Target. Heatmaps showed rightward clustering, reduced left-sided exploration, and limited whole-screen scanning. AAC/eye-tracking did not provide formal diagnostic proof of neglect, but it supported ecological recognition of a neglect-like lateralized exploratory pattern under less guided conditions.
Space situational awareness increasingly relies on optical observations to detect and track resident space objects and to estimate spacecraft attitude. Many existing resources are synthetic or restricted, and few provide on orbit, wide field of view imagery with joint labels for space objects and stars. We present a dataset of near-infrared images acquired by the Fast Auroral Imager on the CASSIOPE spacecraft between January and August 2023. The collection comprises 1,378 frames with astrometrically calibrated stars and 4,237 manually verified resident space object instances across 160 transits, accompanied by spacecraft ephemeris, attitude, and image quality metrics. We describe the acquisition conditions, calibration and annotation pipeline, and perform technical validation of pointing stability, astrometric accuracy, annotation reliability, and background characteristics. The dataset supports tasks such as resident space object detection in dense star fields, multi-object tracking under realistic orbital motion, and attitude estimation from star tracker class imagery, and is intended as a shared resource for space situational awareness and navigation studies.
Fluorescence microscopy in deep tissue is strongly degraded by optical aberrations, leading to reduced signal-to-noise ratio and spatial resolution. Conventional adaptive optics (AO) relies on physical wavefront-modulation hardware and iterative correction procedures, which increase system complexity and, under photon-limited deep-tissue conditions, constrain temporal resolution. We present a deep-learning-based computational adaptive optics framework, termed virtual deformable mirror AO (VDM-AO), that enables fully digital aberration correction without physical wavefront-modulation hardware. Central to this approach are dual-near-infrared lanthanide-doped upconversion nanoparticles that function as embedded guide stars for aberration sensing in scattering tissue. By integrating Zernike-based aberration modeling with a residual channel attention network, VDM-AO predicts 28 Zernike modes and digitally reconstructs aberration-corrected images from heavily distorted inputs. This strategy accurately recovers severely distorted images and achieves high-resolution imaging at depths up to 360 μm. By introducing UCNP guide stars into computational AO, this approach provides a low-cost, high-throughput solution for reliable deep-tissue aberration correction.
Socioeconomic disadvantage is increasingly recognized as an important factor associated with outcomes after total joint arthroplasty (TJA). The Area Deprivation Index (ADI) has emerged as a validated measure of socioeconomic disadvantage that specifically captures individual neighborhood levels of structural and material deprivation based on income, education, employment, and housing characteristics. Prior research has demonstrated ADI to be associated with surgical outcomes; however, its relationship to postoperative outcomes after THA and TKA, procedures in which outcomes depend highly on institutional and structural support, home environment, and accessible postacute care resources, has not been well synthesized. Prior studies provide a broad overview of heterogeneous measures of socioeconomic disadvantage that are not directly comparable. (1) Is a higher ADI associated with increased postoperative healthcare utilization after primary THA and TKA? (2) Is a higher ADI associated with differences in patient-reported outcome measures (PROMs)? (3) Is a higher ADI associated with increased postoperative complications? (4) Is ADI associated with differences in implant survivorship after TJA? A systematic review of four databases-Ovid Medline, Embase, Cochrane Library, and Web of Science Core Collection-was performed from their inception to March 27, 2025. Each database was last searched on March 27, 2025. In all, 128 records were available. Studies were included if they evaluated patients receiving primary THA or TKA and examined ADI in the Results section of the manuscript in terms of any of the following: 90-day outcomes, healthcare utilization, complications, reoperations, revisions, cost, or PROMs. Studies were excluded if they examined revision hip or knee arthroplasty, hemiarthroplasty, or arthroplasty of any other joint; did not evaluate outcomes in association with ADI; or were case reports, systematic reviews, conference abstracts, editorials, or narrative reviews. Sixteen studies were included for final review. Two reviewers independently screened studies, extracted data, and assessed methodological quality using the Newcastle-Ottawa Scale (NOS), which has a maximum quality score of nine stars. Included studies had a median (range) NOS score of 8 stars (7 to 9), suggesting that most were of good quality with a low risk of bias. Results were synthesized qualitatively; meta-analyses were not performed because of the heterogeneity of included studies. A higher ADI was consistently associated with greater healthcare utilization, including prolonged length of stay, increased likelihood of nonhome discharge, and increased odds of emergency department visits. PROMs demonstrated worse absolute postoperative scores and lower likelihood of achieving patient acceptable symptom states among patients who live in high ADI neighborhoods despite comparable levels of improvement across all groups. Overall, ADI was not associated with reaching the standard minimum clinically important difference (MCID). All groups achieved the MCID on all domains of the Hip Disability and Osteoarthritis Outcome Score, Knee Injury and Osteoarthritis Outcome Score, and Patient-Reported Outcomes Measurement Information System short forms regardless of ADI. A higher ADI was associated with increased odds of medical complications such as infection, venous thromboembolism, cardiopulmonary events, and acute kidney injury. Evidence on implant survivorship was limited but suggested increased odds of reoperation and periprosthetic joint infection within 90 days and increased odds of aseptic revision beyond 90 days in populations with more severe levels of deprivation as measured by the ADI. Higher neighborhood socioeconomic deprivation was independently associated with worse postoperative outcomes, greater resource utilization, and signals of inferior early implant survivorship after THA and TKA. The ADI provides meaningful insight into neighborhood-level social risk beyond traditional clinical factors and individual patient demographics and may help identify patients who may benefit from interventions such as more intensive preoperative medical management of comorbidities, tailored perioperative support, easily accessible rehabilitation, or closer postoperative follow-up. Incorporating the ADI into risk-adjustment models and care pathways may help clinicians better anticipate possible barriers to recovery and may help ensure that patients from less affluent communities achieve the results they seek after lower extremity arthroplasty. Level III, therapeutic study.
Dark matter (DM) models with a conserved particle-antiparticle number, n_{χ}-n_{χ[over ˜]}, and the asymmetry in the cosmological abundance n_{χ}≠n_{χ[over ˜]}, are known to be challenged by the existence of old neutron stars (NSs), as the sufficient accumulation of DM will lead to the collapse of NSs into black holes. We demonstrate that the applicability of these constraints is much wider and covers models with symmetric populations of DM, n_{χ}=n_{χ[over ˜]}, as the process of DM capture regulated by a nucleon-DM scattering can be inherently asymmetric, σ_{χn}≠σ_{χ[over ˜]n}. The asymmetry is induced by the interference of different types of χ-n interactions, provided that their combination is odd under charge conjugation in the DM sector, C_{χ}, and even under combined parity P_{χ+n}. We provide a complete analysis of DM-nucleon bilinear χ-n interactions and find that this asymmetry is very generic. Using canonical NS parameters and local DM halo inputs, we exclude spin-averaged scattering cross sections down to σ_{nχ}≳10^{-46}  cm^{2} at DM mass m_{χ}≲10^{10}  GeV for the maximally asymmetric capture rate and show that the constraints persist down to very small values of the cross-section asymmetry, A=(σ_{χn}-σ_{χ[over ˜]n})/(σ_{χn}+σ_{χ[over ˜]n})≳10^{-5}.
We compare suicidal behavior outcomes for adolescents who select "no response" on Ask Suicide-Screening Questions (ASQ) items in the emergency department (ED) with those of adolescents who screen negative or positive. The multisite Emergency Department Screen for Teens at Risk for Suicide (ED-STARS) study prospectively enrolled adolescents at ED visits, randomizing a subset to follow-up of six-month duration. Participants and parents/guardians completed mental health surveys during the ED encounter and (if applicable) at 3- and 6-month. Risk group was assigned based on ED ASQ score (positive, negative, or nonresponse). Primary outcomes were suicidal ideation, suicide attempt, and mental health service use within 6 months. There were 6411 participants assigned to an ASQ group; 2296 participated in follow-up. Nonresponse was associated with intermediate risk for suicidal ideation (nonresponse group adjusted odds ratio [OR] 2.14 [95% CI 1.33-3.41]; positive group 4.35 [2.93-6.51]), attempt (nonresponse group adjusted OR 2.82 [0.97-8.41]; positive group 5.35 [2.25-14.33]), and mental health care receipt (nonresponse group unadjusted OR 3.42 [1.56-7.59]; positive group 9.88 [5.60-17.79]). Youth choosing nonresponse on suicide screening questions may be at elevated risk for suicidal ideation and behavior; ED clinicians should not default to treating these youth as negative screens.
The interaction between planetary atmosphere and stellar winds governs atmospheric evolution in unmagnetized planets. Generally, an interplanetary magnetic field (IMF) drapes around the planetary ionosphere, creating a magnetic barrier that deflects stellar winds and leads to the formation of an induced magnetosphere. However, whether an induced magnetosphere can form under radial IMF conditions where the IMF aligns with solar wind flow in our Solar System remains controversial. By analyzing joint observations from the Tianwen-1 orbiter and the Mars Atmosphere and Volatile Evolution mission combined with hybrid numerical simulations, we clearly demonstrate the formation of Mars' induced magnetosphere during the radial IMF for the first time. This induced magnetosphere comprises a draped magnetic field and an induced magnetic field. Magnetic pressure buildup above the ionosphere surpasses incident solar wind pressure, which establishes a stable magnetic barrier. This finding indicates that the draped magnetic field still forms under a radial IMF. The formation of Mars' induced magnetosphere under the radial IMF could be a general pattern for the interaction between the IMF and planetary atmosphere, which can be referred to terrestrial exoplanets within the close-in habitable zone of dwarf stars. This work clarifies the fundamental understanding of solar wind interactions with unmagnetized planets across diverse solar wind conditions.
Unsupervised machine learning is widely used to mine large, unlabelled datasets to make data-driven discoveries in critical domains such as climate science, biomedicine, astronomy, chemistry and more. However, despite its widespread utilization, there is a lack of standardization in unsupervised learning workflows for making reliable and reproducible scientific discoveries. In this paper, we present a structured workflow for using unsupervised learning techniques in science. We highlight and discuss best practices starting with formulating validatable scientific questions, conducting robust data preparation and exploration, using a range of modelling techniques, performing rigorous validation by evaluating the stability and generalizability of unsupervised learning conclusions, and promoting effective communication and documentation of results to ensure reproducible scientific discoveries. To illustrate our proposed workflow, we present a case study from astronomy, seeking to refine globular clusters of Milky Way stars based upon their chemical composition. Our case study highlights the importance of validation and illustrates how the benefits of a carefully designed workflow for unsupervised learning can advance scientific discovery. This article is part of the theme issue 'Statistical workflow'.
Whale falls are biodiversity oases at seabeds1-6, yet their record from the oceans has remained sparse and fragmentary6,7. Here we report the discovery of a vast whale necropolis in the Diamantina Zone (4,616- to 7,001-m depth), extending about 1,200 km along the sea floor of the southeastern Indian Ocean. This area has a deep and extensive accumulation comprising five modern natural whale-fall communities and 476 fossil cetaceans recorded. We show that carcasses host specialized communities dominated by brittle stars, bone-boring worms and chemosynthesis-based bivalves and that the fossil record in this area comprises both extant and extinct deep-diving beaked whales. Isotopic dating shows that whale falls in this region have occurred since at least 5.3 million years ago. These findings reshape the understanding of the limits and biogeography of whale-fall ecosystems and establish some deep sea floors as a fossil archive for tracing cetacean evolution over geological time.
Newer-generation drug-eluting stents (DES) remain associated with late adverse events, necessitating continued innovation. The Focus np (Abluminus np, Concept Medical, Tampa, FL, USA) is a novel thin-strut cobalt-chromium sirolimus-eluting stent featuring a polymer-free metallic platform with abluminal phospholipid submicron carrier coating and fusion coating extending drug delivery to stent shoulders and exposed balloon surfaces, representing the only contemporary DES integrating polymer-free stent and drug-coated balloon functionalities into a single platform.. This review summarizes the device concept, preclinical findings, early clinical experience, and ongoing randomized controlled trials evaluating the device. This device introduces a hybrid design featuring 73 μm struts with abluminal phospholipid coating providing biphasic sirolimus release over 40 days with prolonged in-tissue exposure, alongside fusion coating covering platform, gaps, and edge zones. Preclinical studies demonstrate rapid endothelialization, minimal inflammation, and complete drug elution by 40 days. Preliminary clinical data in all-comers show low major adverse cardiovascular event rates without stent thrombosis at 12 months. The STARS DAPT pilot trial (NCT05785897) is evaluating single antiplatelet therapy following abbreviated dual antiplatelet therapy versus conventional regimens in ST-segment elevation myocardial infarction patients undergoing primary percutaneous coronary intervention with this device. However, large-scale randomized evidence remains limited.