We present a comprehensive study of host galaxies of radio sources within the 1.35$R_{200}$ of the Coma cluster by combining deep 144MHz observations from the LOFAR Two-Metre Sky Survey (LoTSS-DR2) with optical spectroscopy and photometry from DESI and SDSS. We identify 79 spectroscopically confirmed cluster members with reliable radio emission and classify them into compact, extended, and tailed subsamples according to their radio morphologies. By combining their radio and optical properties, we find compact radio sources are predominantly associated with massive, quiescent galaxies driven by AGN activity, while tailed sources are largely hosted by star-forming galaxies, tracing ongoing ram pressure stripping (RPS). Using phase-space analysis and a projected infall time proxy ($d_R$), we find that extended sources are preferentially located in the cluster outskirts ($d_R > 1$), while tailed sources are concentrated in the intermediate infall region ($0.4 < d_R < 1.0$), highlighting the influence of the dense intracluster medium.

Environmental processes drive galaxy evolution, with the impact varying significantly across different stellar masses. We present a comprehensive environmental analysis of the galaxies within a 10^∘× 10^∘ field around A2029, utilizing high-density spectroscopic data from the DESI and SDSS surveys. We investigate the quenched fraction (f_Q) and red fraction (f_red) as functions of local surface density (log_10 Σ_5) across three stellar mass intervals (low-mass: 9.5 ≤log M_⋆/M_⊙ < 10.0; medium-mass: 10.0 ≤log M_⋆/M_⊙ < 10.5; high-mass: log M_⋆/M_⊙≥ 10.5 ). Our results show that, for galaxies of all masses, both star formation activity and galaxy color are strongly correlated with the local density. Although the environmental dependence of both the quenched and red fractions is somewhat weaker in low-mass galaxies than in their high-mass counterparts, the variations remain significant. This suggests that galaxy colors, even for low-mass systems, can serve as effective tracers of large-scale structure.

Context. It is well established that the cluster environment effectively quenches star formation in member galaxies. Amis. We aim to explore how the accretion path of infalling galaxies influences the cluster-driven quenching process. Methods. We compiled a large spectroscopic galaxy sample around 25 low-redshift, X-ray luminous massive clusters. We identified cluster substructures using the Blooming Tree algorithm and distinguished between galaxies accreted as part of group-scale structures and those accreted in isolation. The infall process was quantified using an infall proxy, d_ R, defined in the R–V diagram. Results. Along the infall process, the quiescent fraction remains approximately constant at the outskirts and then increases steadily toward cluster center, with a transition occurring around d_ R∼ 2.5. We find that group-associated galaxies follow a distinct quenching track compared to isolated galaxies, indicating a dual effect of group-scale environments. At the early infall stages, group galaxies exhibit a higher quiescent fraction, consistent with “pre-processing” in group-scale halos. However, after entering the cluster environment, the rise in their quiescent fraction is delayed to smaller d_ R compared to isolated galaxies. This suggests a phenomenological “protection” effect, in which group-scale halos buffer member galaxies against rapid cluster-driven quenching. Conclusions. We conclude that group-scale environments affect quenching in two ways: via pre-processing prior to cluster infall, and through a subsequent protection effect within the cluster environment.

The structure of open clusters provides key insights into their evolution and the dynamics of the Milky Way. Using Gaia DR3 data, we applied a hierarchical clustering algorithm to the open cluster NGC 752 based on the kinematical information and identified four substructures corresponding to different stages of disintegration. The cluster exhibits a pronounced signature of mass segregation. Its outer members show a clear expansion trend with a velocity of 0.25 km s(-1) in the plane of the sky. In addition, the system shows a projected rotational pattern with an angular velocity of approximately 0.03 rad Myr(-1). We also identified a correlation between the escape times of disturbed members and the epochs at which the cluster crossed the Galactic disk, highlighting the role of Galactic tidal forces in accelerating cluster dissolution. We conclude that hierarchical clustering based on projection bounding energy is effective for studying the internal structure of star clusters, but it has limitations when dealing with unconstrained structures such as tidal tails.

Context. The environment plays a crucial role in galaxy evolution, particularly for galaxies infalling into clusters. Accurately estimating the infall times of galaxies from observations can significantly enhance our understanding of the environmental effects on galaxy evolution. Aims. This paper aims to evaluate existing methods for estimating infall times via the R-V diagram, explore possible strategies to improve accuracy in estimating infall times, and discuss fundamental limitations. Methods. We utilize a TNG300-1 simulation and construct the R-V diagram that is directly comparable to the observations. Using the same dataset, we systematically compare four commonly used methods, including the projected radii, caustic profiles, and two discrete methods. A simple linear partition is also considered as a reference. Results. Each method exhibits distinct characteristics. While the linear partition slightly outperforms other methods, all methods suffer from limited accuracy (≳ 2.6 Gyr), constrained by the intrinsic dispersion (2.53 Gyr) of infall times in the R-V diagram. Given this limit, we explore two potential approaches that can improve accuracy: (1) the infall time dispersion is smaller in more dynamically relaxed clusters, and (2) employing two estimates of infall times instead of one reduces the dispersion to ≲1.5 Gyr. We further demonstrate that the intrinsic dispersion primarily arises from orbital overlap: galaxies in different orbital phases overlap with each other in the R-V diagram and thus appear indistinguishable. Conclusions. Orbital overlap fundamentally limits the accuracy of infall time estimation. The linear partition approach could be a simple and robust estimation.

Galaxy formation and evolution are hierarchical. The most massive galaxies are thought to form their central regions early through violent dissipational processes, then grow inside-out by accreting smaller satellites. While widely supported, direct observational confirmation of this process in individual galaxies remains lacking, except for the Milky Way. We present a detailed analysis of globular cluster (GC) candidates within a 70 ′ (∼190 kpc) radius around the nearest S0 galaxy, NGC 3115, using images in g , r , z bands from the Dark Energy Spectroscopic Instrument Legacy Imaging Surveys and data from Gaia. We report the discovery of mass stratification in the GC system (GCS), evident in two ways: first, the effective radius of the GCS increases monotonically from the bright to faint end, up to the detection limit near the turnover magnitude of the GC luminosity function (GCLF); second, the GCLF shows fainter turnover magnitudes and smaller standard deviations at larger galactocentric radii. This stratification cannot be readily explained by radial migration or tidal dissolution, but most likely reflects the hierarchical assembly of NGC 3115’s stellar halo, with later-accreted satellites deposited across broader galactocentric distances. This interpretation is supported by cosmological simulations of subhalos with comparable mass and bulge-to-total mass ratios and is consistent with the negative color gradients observed in the GCS. Additionally, we identify several substructures within the GCS, indicating ongoing assembly of NGC 3115. This work highlights the power of GCS as tracers of galaxy assembly and sets the stage for upcoming space-based wide-field imaging surveys to constrain the assembly of massive galaxies.

Context. The environment plays a crucial role in galaxy evolution, particularly for galaxies infalling into clusters. Accurately estimating the infall times of galaxies from observations can significantly enhance our understanding of the environmental effects on galaxy evolution. Aims. This paper is aimed at evaluating existing methods for estimating infall times via the R − V diagram. Here, we explore plausible strategies for improving the accuracy in estimating infall times and we discuss the fundamental limitations. Methods. We utilised a TNG300-1 simulation and constructed the R − V diagram that is directly comparable to the observations. Using the same dataset, we systematically compared four commonly used methods, including the projected radii, caustic profiles, and two discrete methods. A simple linear partition was also considered as a reference. Results. Each method exhibits distinct characteristics. While the linear partition slightly outperforms other methods, all methods suffer from limited accuracy (≳2.6 Gyr), constrained by the intrinsic dispersion (2.53 Gyr) of infall times in the R − V diagram. Given this limit, we explored two potential approaches that could improve the accuracy: (1) the infall time dispersion is smaller in more dynamically relaxed clusters and (2) employing two estimates of infall times instead of one reduces the dispersion to ≲1.5 Gyr. We further demonstrate that the intrinsic dispersion primarily arises from orbital overlap: galaxies in different orbital phases overlap with each other in the R − V diagram and thus appear indistinguishable. Conclusions. Orbital overlap fundamentally limits the accuracy of infall time estimation. The linear partition approach could be a simple and robust estimation.

The Einstein Probe (EP) is an interdisciplinary mission of time-domain and X-ray astronomy. Equipped with a wide-field lobster-eye X-ray focusing imager, EP will discover cosmic X-ray transients and monitor the X-ray variability of known sources in 0.5–4 keV, at a combination of detecting sensitivity and cadence that is not accessible to the previous and current wide-field monitoring missions. EP can perform quick characterisation of transients or outbursts with a Wolter-I X-ray telescope onboard. In this paper, the science objectives of the EP mission are presented. EP is expected to enlarge the sample of previously known or predicted but rare types of transients with a wide range of timescales. Among them, fast extragalactic transients will be surveyed systematically in soft X-rays, which include γ-ray bursts and their variants, supernova shock breakouts, and the predicted X-ray transients associated with binary neutron star mergers. EP will detect X-ray tidal disruption events and outbursts from active galactic nuclei, possibly at an early phase of the flares for some. EP will monitor the variability and outbursts of X-rays from white dwarfs, neutron stars and black holes in our and neighbouring galaxies at flux levels fainter than those detectable by the current instruments, and is expected to discover new objects. A large sample of stellar X-ray flares will also be detected and characterised. In the era of multi-messenger astronomy, EP has the potential of detecting the possible X-ray counterparts of gravitational wave events, neutrino sources, and ultra-high energy γ-ray and cosmic ray sources. EP is expected to help advance the studies of extreme objects and phenomena revealed in the dynamic X-ray universe, and their underlying physical processes. Besides EP’s strength in time-domain science, its follow-up telescope, with excellent performance, will also enable advances in many areas of X-ray astronomy.

Objective: To identify risk factors for Lymph Node Metastasis (LNM) in pT3-4 Laryngeal Squamous Cell Carcinoma (LSCC) patients with negative margins, and develop a nomogram to predict LNM risk. Methods: 872 patients were divided into training (2010-2014) and validation (2015-2016) cohorts. Univariate and multivariate analyses identified LNM risk factors. A nomogram incorporating significant factors was developed in the training cohort. Results: Smoking history, maximal tumor diameter >= 3.0 cm, depth of tumor invasion >1.0 cm, and supraglottic tumor location were significantly associated with LNM on multivariate analysis. A predictive nomogram incorporating these factors showed good discrimination (C-index > 0.7) in both cohorts. Patients were stratified into low, moderate and high-risk subgroups based on total risk scores. Conclusions: A LNM risk prediction model and risk grouping system was established, which may aid treatment selection for pT3-4 LSCC patients. The model and algorithm could help optimize neck management for this high- risk patient population. Level of evidence: 2.

The Blooming Tree (BT) algorithm, based on the hierarchical clustering method, is designed to identify clusters, groups, and substructures from galaxy redshift surveys. We apply the BT algorithm to a wide-field (10× 10 deg^2) spectroscopic dataset centered on the galaxy cluster A2029. The BT algorithm effectively identifies all the X-ray luminous clusters and most of the optical clusters known in the literature, numerous groups, and the filaments surrounding the clusters, associating a list of galaxy members to each structure. By lowering the detection threshold, the BT algorithm also identifies the three superclusters in the field. The BT algorithm arranges the clusters and groups that make up the superclusters in a hierarchical tree according to their pairwise binding energy: the algorithm thus unveils the possible accretion history of each supercluster and their future evolution. These results show how the BT algorithm can represent a crucial tool to investigate the formation and evolution of cosmic structures on non-linear and mildly non-linear scales.

Immunoscore (IS), based on CD3/CD8, has been proposed to characterize the immune landscape of the tumor immune microenvironment and has demonstrated an association with the prognosis of laryngeal squamous cell carcinoma (LSCC). However, traditional IS does not include immunosuppressive cells. The purpose of this study is to evaluate the prognostic performance of cytotoxic-T-lymphocytes to immunosuppressive cells ratio (CIL) in laryngeal squamous cell carcinoma (LSCC) patients. Two cohorts were included in this study: The training cohort (N = 75) consisted of tumor tissue microarrays from LSCC patients in our department, and the validation cohort (N = 116) utilized bulk RNA-seq data from the TCGA database. Patients with high IS or CIL showed significantly prolonged overall survival and disease-free survival in both cohorts. Upon analyzing the relative contribution of each parameter, it was found that CIL exhibited the highest significance among the factors examined. It emerged as the strongest predictor of overall survival, emphasizing its crucial influence in determining the outcomes. The prognostic ability of IS-TCGA was similar to the original IS. Additionally, high CILM2-TCGA was associated with prolonged survival of patients with LSCC in the TCGA dataset. CIL, which is easier to construct than IS, proves to be reliable in predicting survival outcomes for patients with LSCC.

Studying the structures of open clusters is crucial for understanding stellar evolution and galactic dynamics. Based on Gaia DR3 data, we apply the hierarchical clustering algorithm to the young open cluster NGC 6530 and group its members into five substructures. By linear tracing with the kinematic information of their members, we find that sub 1 is the core of the cluster. It is expanding slowly. Sub 2 consists of less-bound members, which began escaping from the core about 0.78 Myr ago. Sub 3 is associated with a young star-forming region. It will merge with the core after 0.72 Myr. Sub 4, as an outskirts group, is also moving toward the core but will not end up falling in. Sub 5 is composed of less-bound members with field contamination. This work reveals the complex internal structure and evolutionary trends of the cluster NGC 6530. It also shows the potential of the hierarchical clustering algorithm in star cluster structure analysis.

Fast and reliable localization of high-energy transients is crucial for characterizing the burst properties and guiding the follow-up observations. Localization based on the relative counts of different detectors has been widely used for all-sky gamma-ray monitors. There are two major methods for this counts distribution localization: $\chi^{2}$ minimization method and the Bayesian method. Here we propose a modified Bayesian method that could take advantage of both the accuracy of the Bayesian method and the simplicity of the $\chi^{2}$ method. With comprehensive simulations, we find that our Bayesian method with Poisson likelihood is generally more applicable for various bursts than $\chi^{2}$ method, especially for weak bursts. We further proposed a location-spectrum iteration approach based on the Bayesian inference, which could alleviate the problems caused by the spectral difference between the burst and location templates. Our method is very suitable for scenarios with limited computation resources or time-sensitive applications, such as in-flight localization software, and low-latency localization for rapid follow-up observations.

The Lobster Eye Imager for Astronomy (LEIA) is the pathfinder of the wide-field X-ray telescope used in the Einstein Probe mission. In this study, we present an image of the Virgo Cluster taken by LEIA in the 0.5–4.5 keV band with an exposure time of ∼17.3 ks in the central region. This extended emission is generally consistent with the results obtained by ROSAT. However, the field is affected by bright point sources due to the instrument’s Point Spread Function (PSF) effect. Through fitting of the LEIA spectrum of the Virgo Cluster, we obtained a temperature of 2.1−0.1+0.3 keV, which is consistent with the XMM-Newton results (∼2.3 keV). Above 1.6 keV, the spectrum is dominated by the X-ray background. In summary, this study validates LEIA’s extended source imaging and spectral resolution capabilities for the first time.

Many X-ray astronomical observatories are dedicated to observing cosmic phenomena such as galaxy clusters, which inevitably involves the influence of background. When observing the universe, there are mainly two types of background: the cosmic X-ray background and the particle background, known as non-X-ray background. Understanding the variation of the particle background is crucial for the observations made by the Einstein Probe (EP) satellite. In order to simulate the observation effects of EP-FXT, this paper utilized fixed-point observation data obtained from eROSITA’s Performance Verification phase and Filter Wheel Closed data to construct a background model. Subsequently, based on the eROSITA background model, an EP-FXT background model was established. Due to the different orbits, the particle background of eROSITA is about seven times that of EP-FXT. Based on this, a comparison was made between the high-particle-background model and the low-particle-background model in the observation of galaxy clusters. The results indicate that, without systematic errors, a high background leads to a 20

This phase II trial aimed to determine the efficacy and safety of induction chemoimmunotherapy of camrelizumab plus modified TPF in locally advanced hypopharyngeal squamous cell carcinoma (LA HSCC) (NCT04156698). The primary endpoint was objective response rate (ORR), and secondary endpoints were 3-year overall survival (OS), progression-free survival (PFS), larynx preservation rate (LPR), and metastasis-free survival (MFS). Patients (cT3-4aN0-2M0), regardless of sex, received induction chemoimmunotherapy for three cycles: camrelizumab 200 mg d1, docetaxel 75 mg/m2 d1, cisplatin 25 mg/m2 d1-3, and capecitabine 800 mg/m2 bid d1-14, q21d. Patients were assigned to radioimmunotherapy if they had a complete or partial response, those with stable or progressive disease underwent surgery and adjuvant (chemo)radiotherapy. Camrelizumab was maintained post-radioimmunotherapy. Fifty-one patients were enrolled with a median follow-up duration of 23.7 months. After induction therapy, the ORR was 82.4% (42/51), meeting the prespecified endpoint. Grade 3/4 adverse events occurred in 26 patients, and no treatment-related death occurred. As three-year outcomes were immature, two-year OS, PFS and LPR were reported. As no distant metastatic event had occurred, MFS was not reported here. The two-year OS, PFS, and LPR rates were 83.0%, 77.1%, and 70.0%, respectively. The induction chemoimmunotherapy of camrelizumab plus TPF showed a high ORR rate with an acceptable safety profile in LA HSCC. Locally advanced hypopharyngeal squamous cell carcinoma is an aggressive form of head and neck cancer with a poor prognosis. Here, the authors report the safety and efficacy of induction camrelizumab (anti-PD-1) and chemotherapy for the treatment of locally advanced hypopharyngeal squamous cell carcinoma.

Background To investigate the impact of radiotherapy (RT) on the distribution and function of peripheral CD8+ T lymphocytes in patients with hypopharyngeal squamous cell carcinoma (HPSCC). Methods A total of 105 HPSCC patients who underwent definitive RT were enrolled. Baseline levels of peripheral immune cells were obtained, and their alteration during RT was evaluated. Flow cytometry was used to analyze T-cell distribution, cytokine secretion, and CD8+ T lymphocyte proliferation capacity. Results Lymphocyte count significantly decreased following radiation and remained in a low level after 1 year of RT. CD3+ T lymphocyte counts decreased significantly, and the CD4+/CD8+ ratio increased in HPSCC patients following radiation. The secretion of IFN-γ from peripheral CD8+ T lymphocytes was significantly reduced after irradiation, while the secretion of TNF-α and perforin did not change significantly. Furthermore, the proliferation capacity of peripheral CD8+ T lymphocytes was decreased following RT. Conclusions RT significantly decreased the number of peripheral T lymphocytes and impaired the secretory function and proliferation ability of CD8+ T lymphocytes in HPSCC patients. These findings provide insight into the mechanisms underlying the therapeutic effects of RT on HPSCC and have implications for optimizing treatment strategies.

We study the structural and dynamical properties of A209 based on Chandra and XMM-Newton observations. We obtain detailed temperature, pressure, and entropy maps with the contour binning method, and find a hot region in the NW direction. The X-ray brightness residual map and corresponding temperature profiles reveal a possible shock front in the NW direction and a cold front feature in the SE direction. Combined with the galaxy luminosity density map we propose a weak merger scenario. A young sub-cluster passing from the SE to NW direction could explain the optical subpeak, the intracluster medium temperature map, the X-ray surface brightness excess, and the X-ray peak offset together.

The analysis of light variation of M87 can help us understand the disc evolution. In the past decade, M87 has experienced several short-term light variabilities related to flares. We also find there are year-scale X-ray variations in the core of M87. Their light variability properties are similar to clumpy-ADAF. By re-analyzing 56 $\it Chandra$ observations from 2007 to 2019, we distinguish the `non-flaring state' from `flaring state' in the light variability. After removing flaring state data, we identify 4 gas clumps in the nucleus and all of them can be well fitted by the clumpy-ADAF model. The average mass accretion rate is $\sim 0.16 \rm M_{\odot} yr^{-1}$. We analyze the photon index($\Gamma$)-flux(2-10keV) correlation between the non-flaring state and flaring state. For the non-flaring states, the flux is inversely proportional to the photon index. For the flaring states, we find no obvious correlation between the two parameters. In addition, we find that the flare always occurs at a high mass accretion rate, and after the luminosity of the flare reaches the peak, it will be accompanied by a sudden decrease in luminosity. Our results can be explained as that the energy released by magnetic reconnection destroys the structure of the accretion disc, thus the luminosity decreases rapidly and returns to normal levels thereafter.

We show how the star formation activity of galaxies is progressively inhibited from the outer region to the center of the massive cluster A2142. From an extended spectroscopic redshift survey of 2239 galaxies covering a circular area of radius ～11 Mpc from the cluster center, we extract a sample of 333 galaxies with known stellar mass, star formation rate, and spectral index D n 4000. We use the Blooming Tree algorithm to identify the substructures of the cluster and separate the galaxy sample into substructure galaxies, halo galaxies, and outskirt galaxies. The substructure and halo galaxies are cluster members, whereas the outskirt galaxies are only weakly gravitationally bound to the cluster. For the cluster members, the star formation rate per stellar mass decreases with decreasing distance R from the cluster center. Similarly, the spectral index D n 4000 increases with R, indicating an increasing average age of the stellar population in galaxies closer to the cluster center. In addition, star formation in substructure galaxies is generally more active than in halo galaxies and less active than in outskirt galaxies, proving that substructures tend to slow down the transition between field galaxies and cluster galaxies. We finally show that most actively star-forming galaxies are within the cluster infall region, whereas most galaxies in the central region are quiescent.