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Peer review, as a cornerstone of scientific research, ensures the integrity and quality of scholarly work by providing authors with objective feedback for refinement. However, in the traditional peer review process, authors often receive vague or insufficiently detailed feedback, which provides limited assistance and leads to a more time-consuming review cycle. If authors can identify some specific weaknesses in their paper, they can not only address the reviewer's concerns but also improve their work. This raises the critical question of how to enhance authors' comprehension of review comments. In this paper, we present SEAGraph, a novel framework developed to clarify review comments by uncovering the underlying intentions behind them. We construct two types of graphs for each paper: the semantic mind graph, which captures the author's thought process, and the hierarchical background graph, which delineates the research domains related to the paper. A retrieval method is then designed to extract relevant content from both graphs, facilitating coherent explanations for the review comments. Extensive experiments show that SEAGraph excels in review comment understanding tasks, offering significant benefits to authors.

Brown dwarfs with measured dynamical masses and spectra from direct imaging are benchmarks that anchor substellar atmosphere cooling and evolution models. We present Subaru SCExAO/CHARIS infrared spectroscopy of HIP 93398 B, a brown dwarf companion recently discovered by Li et al. 2023 as part of an informed survey using the Hipparcos-Gaia Catalog of Accelerations. This object was previously classified as a T6 dwarf based on its luminosity, with its independently-derived age and dynamical mass in tension with existing models of brown dwarf evolution. Spectral typing via empirical standard spectra, temperatures derived by fitting substellar atmosphere models, and J-H, J-K and H-L' colors all suggest that this object has a substantially higher temperature and luminosity, consistent with classification as a late-L dwarf near the L/T transition (T = 1200$^{+140}_{-119}$ K) with moderate to thick clouds possibly present in its atmosphere. When compared with the latest generation of evolution models that account for clouds with our revised luminosity and temperature for the object, the tension between the model-independent mass/age and model predictions is resolved., Comment: Accepted to AJ, 19 pages

As exoplanet surveys reach ever-higher sensitivities and durations, planets analogous to the solar system giant planets are increasingly within reach. HD 28185 is a Sun-like star known to host a $m\sin i=6 M_J$ planet on an Earth-like orbit; more recently, a brown dwarf with a more distant orbit has been claimed. In this work we present a comprehensive reanalysis of the HD 28185 system, based on 22 years of radial velocity observations and precision Hipparcos-Gaia astrometry. We confirm the previous characterisation of HD 28185 b as a temperate giant planet, with its $385.92^{+0.06}_{-0.07}$ day orbital period giving it an Earth-like incident flux. In contrast, we substantially revise the parameters of HD 28185 c; with a new mass of $m=6.0\pm0.6 M_J$ we reclassify this companion as a super-jovian planet. HD 28185 c has an orbital period of $24.9^{+1.3}_{-1.1}$ years, a semi-major axis of $8.50^{+0.29}_{-0.26}$ AU, and a modest eccentricity of $0.15\pm0.04$, resulting in one of the most Saturn-like orbits of any known exoplanet. HD 28185 c lies at the current intersection of detection limits for RVs and direct imaging, and highlights how the discovery of giant planets at $\approx$10 AU separations is becoming increasingly routine., Comment: 17 pages, 8 figures, 7 tables. Published in MNRAS

We describe the motivation, design, and early results for our 42-night, 125 star Subaru/SCExAO direct imaging survey for planets around accelerating stars. Unlike prior large surveys, ours focuses only on stars showing evidence for an astrometric acceleration plausibly due to the dynamical pull of an unseen planet or brown dwarf. Our program is motivated by results from a recent pilot program that found the first planet jointly discovered from direct imaging and astrometry and resulted in a planet and brown dwarf discovery rate substantially higher than previous unbiased surveys like GPIES. The first preliminary results from our program reveal multiple new companions; discovered planets and brown dwarfs can be further characterized with follow-up data, including higher-resolution spectra. Finally, we describe the critical role this program plays in supporting the Roman Space Telescope Coronagraphic Instrument, providing a currently-missing list of targets suitable for the CGI technological demonstration without which the CGI tech demo risks failure., Comment: 13 pages, 7 figures; Proc. SPIE in press

We present the joint astrometric and direct imaging discovery, mass measurement, and orbital analysis of HD 63754 B (HIP 38216 B), a companion near the stellar-substellar boundary orbiting ~20 AU from its Sun-like host. HD 63754 was observed in our ongoing high-contrast imaging survey targeting stars with significant proper-motion accelerations between Hipparcos and Gaia consistent with wide-separation substellar companions. We utilized archival HIRES and HARPS radial velocity (RV) data, together with the host star's astrometric acceleration extracted from the Hipparcos-Gaia Catalog of Accelerations (HGCA), to predict the location of the candidate companion around HD 63754 A. We subsequently imaged HD 63754 B at its predicted location using the Near Infrared Camera 2 (NIRC2) in the $L'$ band at the W. M. Keck Observatory. We then jointly modeled the orbit of HD 63754 B with RVs, Hipparcos-Gaia accelerations, and our new relative astrometry, measuring a dynamical mass of ${81.9}_{-5.8}^{+6.4} M_{jup}$, an eccentricity of ${0.260}_{-0.059}^{+0.065}$, and a nearly face-on inclination of $174.81_{-0.50}^{+0.48}$ degrees. For HD 63754 B, we obtain an L' band absolute magnitude of $L' = 11.39\pm0.06$ mag, from which we infer a bolometric luminosity of $log(L_{bol}/L_{\odot})= -4.55 \pm0.08$ dex using a comparison sample of L and T dwarfs with measured luminosities. Although uncertainties linger in age and dynamical mass estimates, our analysis points toward HD 63754 B's identity as a brown dwarf on the L/T transition rather than a low-mass star, indicated by its inferred bolometric luminosity and model-estimated effective temperature. Future RV, spectroscopic, and astrometric data such as those from JWST and Gaia DR4 will clarify HD 63754 B's mass, and enable spectral typing and atmospheric characterization.

Multi-channel electrophysiology systems for recording of neuronal activity face significant data throughput limitations, hampering real-time, data-informed experiments. These limitations impact both experimental neurobiology research and next-generation neuroprosthetics. We present a novel solution that leverages the high integration density of 22nm FDSOI CMOS technology to address these challenges. The proposed highly integrated programmable System-on-Chip comprises 68-channel 0.41 \textmu W/Ch recording frontends, spike detectors, 16-channel 0.87-4.39 \textmu W/Ch action potential and 8-channel 0.32 \textmu W/Ch local field potential codecs, as well as a MAC-assisted power-efficient processor operating at 25 MHz (5.19 \textmu W/MHz). The system supports on-chip training processes for compression, training and inference for neural spike sorting. The spike sorting achieves an average accuracy of 91.48% or 94.12% depending on the utilized features. The proposed PSoC is optimized for reduced area (9 mm2) and power. On-chip processing and compression capabilities free up the data bottlenecks in data transmission (up to 91% space saving ratio), and moreover enable a fully autonomous yet flexible processor-driven operation. Combined, these design considerations overcome data-bottlenecks by allowing on-chip feature extraction and subsequent compression., Comment: 26 pages, 14 figures, 1 table, Journal

The two planets of the HAT-P-11 system represent fascinating dynamical puzzles due to their significant eccentricities and orbital misalignments. In particular, HAT-P-11 b is on a close-in orbit that tides should have circularized well within the age of the system. Here we propose a two-step dynamical process that can reproduce all intriguing aspects of the system. We first invoke planet-planet scattering to generate significant eccentricities and mutual inclinations between the planets. We then propose that this misalignment initiated von-Zeipel-Lidov-Kozai cycles and high-eccentricity migration that ultimately brought HAT-P-11 b to its present-day orbit. We find that this scenario is fully consistent only when significant tidally-driven radius inflation is accounted for during the tidal migration. We present a suite of N-body simulations exploring each phase of evolution and show that this scenario is consistent with all observational posteriors and the reported age of the system., Comment: 17 pages, 8 figures, accepted in ApJ

Planet-star obliquity and planet-planet ]mutual inclination encode a planetary system's dynamical history, but both of their values are hard to measure for misaligned systems with close-in companions. HAT-P-11 is a K4 star with two known planets: a close-in, misaligned super-Neptune with a $\approx$5-day orbit, and an outer super-Jupiter with a $\approx$10-year orbit. In this work we present a joint orbit fit of the HAT-P-11 system with astrometry and S-index corrected RV data. By combining our results with previous constraints on the orientation of the star and the inner planet, we find that all three angular momenta -- those of the star, planet b, and planet c -- are significantly misaligned. We confirm the status of planet c as a super-Jupiter, with $2.68\pm0.41\, \mathrm{M_{\rm Jup}}$ at a semimajor axis of $4.10\pm0.06\,$AU, and planet b's mass of $\mathrm{M_b\sin{i_b}}=0.074\pm0.004\, \mathrm{M_{\rm Jup}}$. We present the posterior probability distribution of obliquity between star A and planet c, and mutual inclination between planet b and planet c., Comment: 14 pages, 10 figures, submitted to AJ

We present the direct-imaging discovery of a substellar companion (a massive planet or low-mass brown dwarf) to the young, $\gamma$ Doradus-type variable star, HIP 39017 (HD 65526). The companion's SCExAO/CHARIS JHK ($1.1-2.4\mu$m) spectrum and Keck/NIRC2 L$^{\prime}$ photometry indicate that it is an L/T transition object. A comparison of the JHK+L$^{\prime}$ spectrum to several atmospheric model grids finds a significantly better fit to cloudy models than cloudless models. Orbit modeling with relative astrometry and precision stellar astrometry from Hipparcos and Gaia yields a semi-major axis of $23.8^{+8.7}_{-6.1}$ au, a dynamical companion mass of $30^{+31}_{-12}$~M$_J$, and a mass ratio of $\sim$1.9\%, properties most consistent with low-mass brown dwarfs. However, its mass estimated from luminosity models is a lower $\sim$13.8 $M_{\rm J}$ due to an estimated young age ($\lesssim$ 115 Myr); using a weighted posterior distribution informed by conservative mass constraints from luminosity evolutionary models yields a lower dynamical mass of $23.6_{-7.4}^{+9.1}$~M$_J$ and a mass ratio of $\sim$1.4\%. Analysis of the host star's multi-frequency $\gamma$ Dor-type pulsations, astrometric monitoring of HIP 39017b, and Gaia Data Release 4 astrometry of the star will clarify the system age and better constrain the mass and orbit of the companion. This discovery further reinforces the improved efficiency of targeted direct-imaging campaigns informed by long-baseline, precision stellar astrometry., Comment: Published in AJ: April 9, 2024

Translation is one of the most fundamental processes in the biological cell. Because of the central role that translation plays across all domains of life, the enzyme that carries out this process, the ribosome, is required to process information with high accuracy. This accuracy often approaches values near unity experimentally. In this paper, we model the ribosome as an information channel and demonstrate mathematically that this biological machine has information-processing capabilities that have not been recognized previously. In particular, we calculate bounds on the ribosome's theoretical Shannon capacity and numerically approximate this capacity. Finally, by incorporating estimates on the ribosome's operation time, we show that the ribosome operates at speeds safely below its capacity, allowing the ribosome to process information with an arbitrary degree of error. Our results show that the ribosome achieves a high accuracy in line with purely information-theoretic means., Comment: 7 pages, 5 figures

We measure precise orbits and dynamical masses and derive age constraints for six confirmed and one candidate Sirius-like systems, including the Hyades member HD 27483. Our orbital analysis incorporates radial velocities, relative astrometry, and Hipparcos-Gaia astrometric accelerations. We constrain the main-sequence lifetime of a white dwarf's progenitor from the remnant's dynamical mass and semi-empirical initial-final mass relations and infer the cooling age from mass and effective temperature. We present new relative astrometry of HD 27483 B from Keck/NIRC2 observations and archival HST data, and obtain the first dynamical mass of ${0.798}_{-0.041}^{+0.10}$ $M_{\odot}$, and an age of ${450}_{-180}^{+570}$ Myr, consistent with previous age estimates of Hyades. We also measure precise dynamical masses for HD 114174 B ($0.591 \pm 0.011$ $M_{\odot}$) and HD 169889 B (${0.526}_{-0.037}^{+0.039}$ $M_{\odot}$), but their age precisions are limited by their uncertain temperatures. For HD 27786 B, the unusually small mass of $0.443 \pm 0.012$ $M_{\odot}$ suggests a history of rapid mass loss, possibly due to binary interaction in its progenitor's AGB phase. The orbits of HD 118475 and HD 136138 from our RV fitting are overall in good agreement with Gaia DR3 astrometric two-body solutions, despite moderate differences in the eccentricity and period of HD 136138. The mass of ${0.580}_{-0.039}^{+0.052}$ $M_{\odot}$ for HD 118475 B and a speckle imaging non-detection confirms that the companion is a white dwarf. Our analysis shows examples of a rich number of precise WD dynamical mass measurements enabled by Gaia DR3 and later releases, which will improve empirical calibrations of the white dwarf initial-final mass relation., Comment: 21 pages, 7 figures

Brown dwarfs with well-measured masses, ages and luminosities provide direct benchmark tests of substellar formation and evolutionary models. We report the first results from a direct imaging survey aiming to find and characterize substellar companions to nearby accelerating stars with the assistance of the Hipparcos-Gaia Catalog of Accelerations (HGCA). In this paper, we present a joint high-contrast imaging and astrometric discovery of a substellar companion to HD 176535 A, a K3.5V main-sequence star aged approximately $3.59_{-1.15}^{+0.87}$ Gyrs at a distance of $36.99 \pm 0.03$ pc. In advance of our high-contrast imaging observations, we combined precision HARPS RVs and HGCA astrometry to predict the potential companion's location and mass. We thereafter acquired two nights of KeckAO/NIRC2 direct imaging observations in the $L'$ band, which revealed a companion with a contrast of $\Delta L'_p = 9.20\pm0.06$ mag at a projected separation of $\approx$0.$\!\!''35$ ($\approx$13 AU) from the host star. We revise our orbital fit by incorporating our dual-epoch relative astrometry using the open-source MCMC orbit fitting code $\tt orvara$. HD 176535 B is a new benchmark dwarf useful for constraining the evolutionary and atmospheric models of high-mass brown dwarfs. We found a luminosity of $\rm log(L_{bol}/L_{\odot}) = -5.26\pm0.07$ and a model-dependent effective temperature of $980 \pm 35$ K for HD 176535 B. Our dynamical mass suggests that some substellar evolutionary models may be underestimating luminosity for high-mass T dwarfs. Given its angular separation and luminosity, HD 176535 B would make a promising candidate for Aperture Masking Interferometry with JWST and GRAVITY/KPIC, and further spectroscopic characterization with instruments like the CHARIS/SCExAO/Subaru integral field spectrograph.

With unprecedented and growing interest in data science education, there are limited educator materials that provide meaningful opportunities for learners to practice statistical thinking, as defined by Wild and Pfannkuch (1999), with messy data addressing real-world challenges. As a solution, Nolan and Speed (1999) advocated for bringing applications to the forefront in undergraduate statistics curriculum with the use of in-depth case studies to encourage and develop statistical thinking in the classroom. Limitations to this approach include the significant time investment required to develop a case study -- namely, to select a motivating question and to create an illustrative data analysis -- and the domain expertise needed. As a result, case studies based on realistic challenges, not toy examples, are scarce. To address this, we developed the Open Case Studies (https://www.opencasestudies.org) project, which offers a new statistical and data science education case study model. This educational resource provides self-contained, multimodal, peer-reviewed, and open-source guides (or case studies) from real-world examples for active experiences of complete data analyses. We developed an educator's guide describing how to most effectively use the case studies, how to modify and adapt components of the case studies in the classroom, and how to contribute new case studies. (https://www.opencasestudies.org/OCS_Guide)., Comment: 16 pages in main text, 3 figures, and 2 tables; 9 page in supplement

Some lung diseases are related to bronchial airway structures and morphology. Although airway segmentation from chest CT volumes is an important task in the computer-aided diagnosis and surgery assistance systems for the chest, complete 3-D airway structure segmentation is a quite challenging task due to its complex tree-like structure. In this paper, we propose a new airway segmentation method from 3D chest CT volumes based on volume of interests (VOI) using gradient vector flow (GVF). This method segments the bronchial regions by applying the cavity enhancement filter (CEF) to trace the bronchial tree structure from the trachea. It uses the CEF in the VOI to segment each branch. And a tube-likeness function based on GVF and the GVF magnitude map in each VOI are utilized to assist predicting the positions and directions of child branches. By calculating the tube-likeness function based on GVF and the GVF magnitude map, the airway-like candidate structures are identified and their centrelines are extracted. Based on the extracted centrelines, we can detect the branch points of the bifurcations and directions of the airway branches in the next level. At the same time, a leakage detection is performed to avoid the leakage by analysing the pixel information and the shape information of airway candidate regions extracted in the VOI. Finally, we unify all of the extracted bronchial regions to form an integrated airway tree. Preliminary experiments using four cases of chest CT volumes demonstrated that the proposed method can extract more bronchial branches in comparison with other methods.