Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. IV. Hβ\beta Time Lags and Implications for Super-Eddington Accretion

We have completed two years of photometric and spectroscopic monitoring of a large number of active galactic nuclei (AGNs) with very high accretion rates. In this paper, we report on the result of the second phase of the campaign, during 2013--2014, and the measurements of five new H$\beta$ time lags out of eight monitored AGNs. All five objects were identified as super-Eddington accreting massive black holes (SEAMBHs). The highest measured accretion rates for the objects in this campaign are $\dot{\mathscr{M}}\gtrsim 200$, where $\dot{\mathscr{M}}= \dot{M}_{\bullet}/L_{\rm Edd}c^{-2}$, $\dot{M}_{\bullet}$ is the mass accretion rates, $L_{\rm Edd}$ is the Eddington luminosity and $c$ is the speed of light. We find that the H$\beta$ time lags in SEAMBHs are significantly shorter than those measured in sub-Eddington AGNs, and the deviations increase with increasing accretion rates. Thus, the relationship between broad-line region size ($R_{_{\rm H\beta}}$) and optical luminosity at 5100\AA, $R_{_{\rm H\beta}}-L_{5100}$, requires accretion rate as an additional parameter. We propose that much of the effect may be due to the strong anisotropy of the emitted slim-disk radiation. Scaling $R_{_{\rm H\beta}}$ by the gravitational radius of the black hole, we define a new radius-mass parameter ($Y$) and show that it saturates at a critical accretion rate of $\dot{\mathscr{M}}_c=6\sim 30$, indicating a transition from thin to slim accretion disk and a saturated luminosity of the slim disks. The parameter $Y$ is a very useful probe for understanding the various types of accretion onto massive black holes. We briefly comment on implications to the general population of super-Eddington AGNs in the universe and applications to cosmology.Comment: 53 pages, 12 figures, 7 tables, accepted for publication in The Astrophysical Journa

Prognostic value of programmed death ligand 1, p53, and Ki-67 in patients with advanced stage colorectal cancer

Current prognostic indicators are ineffective for identifying advanced stage colorectal cancer (CRC) patients with high risk of recurrence after surgical resection. We investigated the prognostic value of p53, Ki-67, and programmed death ligand 1 (PD-L1) in 254 patients with stage II and III CRC. The expression of p53 was positive in 63% of cases. Up-regulation of p53 was associated with smaller tumor size (P = .001) and higher Ki-67 labeling index (LI) (P = .031). The tumor Ki-67 LI was high (≥ 20%) in 197 (78%) of the patients. High Ki-67 LI was associated with higher TNM stage (P = .031), positive p53 expression (P = .031), and negative PD-L1 expression (P = .003). The five-year relapse-free survivals (RFS) were 53% and 89%, respectively, for the p53-positive and Ki-67 LI-high patients and the p53-negative and Ki-67 LI-low patients (P < .001). In univariate analysis, negative p53 (P = .001), low Ki-67 LI (P = .006), low PD-L1 expression (P = .044), low TNM stage (P < .001), recto-sigmoid location (P = .026), and small size (P = .013) were significantly related to RFS. In multivariate Cox regression analysis, positive p53 expression (hazard ratio [HR]: 2.48; 95% confidence interval: 1.34–4.59, P = .004), high Ki-67 LI (HR: 2.62; 95% CI: 1.12–6.14, P = .027) and high TNM stage (HR: 2.598, 95% CI: 1.55–4.37, P < .001,) were independent predictors of unfavorable prognosis. In summary, PD-L1, Ki-67, and p53 staining individually had significant prognostic value for patients with stage II and III CRC. Moreover, combining p53 H-score ≥ 35 and Ki-67 LI ≥ 20% identifies patients with poor clinical outcome

Demonstration of a microelectromechanical tunable F-P cavity based on graphene-bonded fiber devices

Taking advantage of the high thermal conductivity of graphene, this paper demonstrates a microelectromechanical (MEM) tunable Fabry-Perot (F-P) cavity, based on a graphene-bonded fiber device (GFD) which acts as a microheater. By increasing the electric current from 0 mA to 8 mA in the heater, the temperature of the GFD can rise and approach a value of 760 K theoretically. This high temperature will cause a deformation of the fiber, allowing the graphene-bonded fiber end to forma gap adjustable F-P cavity with a cleaved single mode fiber. The gap in the cavity can be reduced by increasing the current applied, leading the transmittance of the cavity to change. In this work, a highly sensitive current sensor (5.9x10⁵nm/A²) and a tunable modelocked fiber laser (1.2x10⁴nm/A²) are created based on the MEM tunable F-P cavity

iKUN: Speak to Trackers without Retraining

Referring multi-object tracking (RMOT) aims to track multiple objects based on input textual descriptions. Previous works realize it by simply integrating an extra textual module into the multi-object tracker. However, they typically need to retrain the entire framework and have difficulties in optimization. In this work, we propose an insertable Knowledge Unification Network, termed iKUN, to enable communication with off-the-shelf trackers in a plug-and-play manner. Concretely, a knowledge unification module (KUM) is designed to adaptively extract visual features based on textual guidance. Meanwhile, to improve the localization accuracy, we present a neural version of Kalman filter (NKF) to dynamically adjust process noise and observation noise based on the current motion status. Moreover, to address the problem of open-set long-tail distribution of textual descriptions, a test-time similarity calibration method is proposed to refine the confidence score with pseudo frequency. Extensive experiments on Refer-KITTI dataset verify the effectiveness of our framework. Finally, to speed up the development of RMOT, we also contribute a more challenging dataset, Refer-Dance, by extending public DanceTrack dataset with motion and dressing descriptions. The codes and dataset are available at https://github.com/dyhBUPT/iKUN.Comment: CVPR 2024 camera-read

Video-based Visible-Infrared Person Re-Identification with Auxiliary Samples

Visible-infrared person re-identification (VI-ReID) aims to match persons captured by visible and infrared cameras, allowing person retrieval and tracking in 24-hour surveillance systems. Previous methods focus on learning from cross-modality person images in different cameras. However, temporal information and single-camera samples tend to be neglected. To crack this nut, in this paper, we first contribute a large-scale VI-ReID dataset named BUPTCampus. Different from most existing VI-ReID datasets, it 1) collects tracklets instead of images to introduce rich temporal information, 2) contains pixel-aligned cross-modality sample pairs for better modality-invariant learning, 3) provides one auxiliary set to help enhance the optimization, in which each identity only appears in a single camera. Based on our constructed dataset, we present a two-stream framework as baseline and apply Generative Adversarial Network (GAN) to narrow the gap between the two modalities. To exploit the advantages introduced by the auxiliary set, we propose a curriculum learning based strategy to jointly learn from both primary and auxiliary sets. Moreover, we design a novel temporal k-reciprocal re-ranking method to refine the ranking list with fine-grained temporal correlation cues. Experimental results demonstrate the effectiveness of the proposed methods. We also reproduce 9 state-of-the-art image-based and video-based VI-ReID methods on BUPTCampus and our methods show substantial superiority to them. The codes and dataset are available at: https://github.com/dyhBUPT/BUPTCampus.Comment: Accepted by Transactions on Information Forensics & Security 202

Structure and dynamics of a glass-forming binary complex plasma with non-reciprocal interaction

In this letter, we present the first numerical study on the structural and dynamical properties of a quasi-two-dimensional (q2D) binary complex plasma with Langevin dynamics simulation. The effect of interaction with non-reciprocity on the structure is investigated by comparing systems with pure Yukawa and with point-wake Yukawa interactions. The long-time alpha-relaxation for the latter system is revealed by plotting and analyzing the intermediate scattering function. The results clearly indicate that a q2D binary complex plasma is a suitable model system to study the dynamics of a glass former. The non-reciprocity of the interactions shifts the glass formation significantly but leads to the same qualitative signatures as in the reciprocal case