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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.

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.

Interstellar objects provide the only directly observable samples of icy planetesimals formed around other stars, and can therefore provide insight into the diversity of physical and chemical conditions occurring during exoplanet formation1-3. Here we report isotopic measurements of the interstellar comet 3I/ATLAS, which reveal an elemental composition unlike any Solar System body. The water in 3I/ATLAS is enriched in deuterium, at a level of D/H = (0.98 ± 0.06)%, which is more than an order of magnitude higher than in known comets, while its range of 12C/13C ratios (141-191 for CO2 and 123-172 for CO) exceeds typical values found in the Solar System, as well as nearby interstellar clouds and protoplanetary disks. Such extreme isotopic signatures indicate formation at temperatures  ≲ 30 K in a relatively metal-poor environment. When interpreted with respect to models for Galactic chemical evolution, the carbon isotopic composition implies that 3I/ATLAS may have accreted as long ago as 12 billion years, following a period of intense, early star formation. 3I/ATLAS thus represents a preserved fragment of an ancient planetary system.

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}.

Brittle stars move with remarkable whole-body coordination despite lacking a central brain. With five identical arms radiating from a central disc, they predominantly adopt a bilaterally symmetrical rowing gait: one arm leads, two neighbouring arms row in synchrony and the remaining arms trail. This raises a puzzle: how does a brainless nervous system generate coherent whole-body gaits, and why does it favour rowing? To address this, this work introduces an in silico framework combining (i) a three-dimensional model of brittle star morphology in a physics simulator, (ii) an artificial neural network (ANN) architecture that mirrors the decentralized arm-level ganglia, which interconnect through the nerve ring and (iii) reinforcement learning (RL) to optimize controllers for locomotion. Analysis of optimized controllers shows that ganglia behave as distributed oscillators whose coupling via the nerve ring yields synchronization, analogous to that of central pattern generators (CPGs). Gait analysis reveals that rowing emerges as the strategy most compatible with the arms' dual role as effectors and sensors. Taken together, these results provide a mechanistic view of how decentralized neural dynamics and sensory constraints shape brittle star locomotion. The presented framework offers an open-ended test bed for hypotheses inaccessible in vivo, and more broadly, for exploring decentralized control in embodied agents. We provide a link to our project web page and interactive results dashboard: https://airo.ugent.be/projects/brittle-star.

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.

Recent growth in hospice has raised concerns about variability in access and quality. This study examines U.S. county-level presence of hospice providers. Quality was assessed using 2023 Centers for Medicare & Medicaid Services Consumer Assessment of Healthcare Providers and Systems Hospice Survey Star Ratings. County-level sociodemographic characteristics were obtained from the U.S. Census Bureau's American Community Survey 2023 five-year sample. Of 7024 hospice providers, 29.2% had publicly available ratings, of which 55.3% were high quality (>3 stars). Of 3222 counties, at least one hospice provider was located in 41.4%, and a high-quality provider was present in 23.6%. Counties with high-quality providers tend to be urban and have higher income, larger populations, higher education, and lower poverty and uninsurance rates. Many U.S. counties have no hospice providers. The presence of high-quality care is markedly lower in rural and poor counties. Missing star ratings limit the utility of public quality data for patient and family decision-making.

Quantitative T1 mapping is a major building block in several multiparametric magnetic resonance imaging (MRI) protocols intended for adaptive radiation therapy. The implementation of these protocols is challenging in anatomical sites that experience large physiological motion. The purpose of this study was to implement and validate motion-resolved quantitative T1 mapping on a 1.5 T MRI linear accelerator (MR-Linac) combining non-Cartesian k-space sampling trajectories with compressed sensing (CS) reconstruction. Four 3-dimensional non-Cartesian k-space trajectories were evaluated: kooshball and stack-of-stars sampling using half- and full-spoke coverage. A variable flip angle acquisition was performed using the spoiled gradient-echo sequence. Gradient delay timing was optimized to minimize trajectory-induced artifacts. Eight CS reconstruction strategies were tested using spatial/spatiotemporal regularization operators. Reconstructions were evaluated and sorted by spatial resolution, bias, and variability. Motion-resolved T1 mapping was validated using two standard phantoms, one healthy volunteer, and one kidney cancer patient using respiratory self-gating and phase-sorted reconstruction. All non-Cartesian T1 maps demonstrated high repeatability and low longitudinal bias in phantom studies, with coefficients of variation below 3.3%. Spatiotemporal regularization preserved spatial resolution and quantitative accuracy at undersampling factors up to 20-fold. In human subjects, non-Cartesian T1 mapping provided improved accuracy and reduced variability in mobile abdominal tissues compared to Cartesian acquisitions. Quantitative T1 mapping using non-Cartesian trajectories and CS reconstruction is feasible on a 1.5 T MR-Linac. The proposed approach enables accurate motion-resolved quantitative imaging within clinically practical acquisition times, establishing a foundation for multiparametric MRI in adaptive radiotherapy.