29 research outputs found
A centi-pc-scale compact radio core in the nearby galaxy M60
M60, an elliptical galaxy located 16.5~Mpc away, has an active nucleus with a
very low luminosity and an extremely low accretion rate. Its central
supermassive black hole has a mass of and a Schwarzschild radii corresponding to . To investigate the nature of its innermost radio
nucleus, data from the Very Long Baseline Array (VLBA) at 4.4 and 7.6~GHz were
reduced. The VLBA images reveal a compact component with total flux densities
of 20~mJy at both frequencies, a size of 0.27~mas (99.7
confidence level), about 0.022~pc () at 7.6~GHz, and a
brightness temperature of ~K. This suggests that the
observed centi-parsec-scale compact core could be attributed to a nonthermal
jet base or an advection-dominated accretion flow (ADAF) with nonthermal
electrons. The extremely compact structure also supports the presence of an
SMBH in the center. Our results indicate that M60 is a promising target for
broad-band VLBI observations at millimeter wavelengths to probe ADAF scenarios
and tightly constrain the potential photon ring (about 28\,as) around its
SMBH.Comment: 15 pages, 5 figures, 3 tables, accepted for publication in
Astrophysical Journa
The role of atorvastatin on the restenosis process post-PTA in a diabetic rabbit model
Correlation Analysis of Health Factors of Elderly People in Traditional Miao Dwellings in Western Hunan
Under the macro context of severe global aging, the typical villages and dwellings of the Miao ethnic group in western Hunan were selected, and the daily life and health status of the local elderly were evaluated through behavioral observation, interviews, and questionnaires (e.g., physiological, psychological, and residential environments). In addition, the health status and relevant evaluation factors of the respondents were correlated and then analyzed using SPSS software. As indicated by the results of this study, the local elderly used all the spaces and functions of the existing dwellings and were satisfied with the spaces except for the toilet. In addition, their physiological functions had declined, and their daily behaviors were affected by a wide variety of physical diseases. From a psychological perspective, more than 60% of the elderly had significant feelings of loneliness and frustration. As indicated by the correlation results, the health status of the elderly in traditional Miao dwellings in western Hunan was positively correlated with family, income, daily acts, dwellings, and infrastructure, and negatively correlated with age. They showed linear correlations with all impact factors: Health = 157.44 − 5.242 ∗ Gender − 1.611 ∗ Age − 0.606 ∗ Education level − 0.411 ∗ Family + 0.001 ∗ Income − 7.191 ∗ Daily acts + 13.621 ∗ Dwelling + 4.682 ∗ Infrastructure + 17.198 ∗ Natural. Based on the results of study, targeted improvement strategies were proposed for the elderly in traditional Miao dwellings in western Hunan from four aspects—infrastructure, traditional dwellings, mental health, and policy support—to improve the health status of the elderly in traditional Chinese villages and towns
Decreased Plasma Nesfatin-1 Level Is Related to the Thyroid Dysfunction in Patients with Type 2 Diabetes Mellitus
Aims. Thyroid dysfunction is frequently observed in patients with type 2 diabetes mellitus (T2DM), but the underlying mechanism is still poorly understood. The present study aimed to investigate whether nesfatin-1 played a role in the thyroid dysfunction in patients with T2DM. Methods. 55 euthyroid patients were enrolled in this study including 30 patients with T2DM and 25 patients with impaired glucose regulation (IGR). 30 age-matched healthy people were also included as the control. The plasma levels of nesfatin-1, thyrotropin (TSH), and glycosylated hemoglobin (HbA1c) as well as the body mass index (BMI) were comparatively analyzed among the three groups. Results. The nesfatin-1 was significantly lower in patients with T2DM than in patients with IGR and in the control. On the contrary, the TSH level was significantly higher in patients with T2DM than in patients with IGR and in the control. Simple regression analysis showed that the plasma nesfatin-1 was negatively correlated with the TSH and HbA1c levels and positively correlated with the BMI. With multiple stepwise regression analysis, the nesfatin-1 remained to be independently correlated with the TSH, BMI, and HbA1c. Conclusions. The study was suggesting a role of nesfatin-1 in thyroid dysfunction in patients with T2DM
Native chemical ubiquitination using a genetically incorporated azidonorleucine
A robust chemical ubiquitination method was developed. The method employed a genetically incorporated azidonorleucine as an orthogonal lysine precursor for the installation of a Gly residue bearing an Nα-auxiliary which mediated the ligation between ubiquitin(1–75)-thioester and the target protein. To demonstrate our methodology, a model protein, K48-linked diubiquitin, was synthesized with an overall yield of 35%.ASTAR (Agency for Sci., Tech. and Research, S’pore)Accepted versio
The effects of glucagon-like peptide-1 receptor agonists on adipose tissues in patients with type 2 diabetes: A meta-analysis of randomised controlled trials.
AimsGlucagon‑like peptide 1 receptor agonist (GLP-1RA) treatment can improve adipose distribution. We performed this meta-analysis to investigate whether GLP-1RAs preferentially reduce visceral adipose tissue (VAT) over subcutaneous adipose tissue (SAT) in patients with type 2 diabetes.Materials and methodsWe searched MEDLINE and the Cochrane Library for randomised controlled trials explicitly reporting changes in VAT and SAT. A random-effects model was performed to estimate the weighted mean difference (MD) for VAT and SAT. Heterogeneity among the studies was assessed using I2 statistics, and publication bias was assessed using Egger's tests. Meta-regression was performed to identify the correlation between changes in adipose tissues and changes in body weight and glycated haemoglobin level.ResultsTen trials with 924 patients were enrolled in the meta-analysis. GLP-1RA treatment led to similar absolute area (cm2) reductions in VAT (MD -21.13 cm2, 95% CI [-29.82, -12.44]) and SAT (MD -22.89 cm2, 95% CI [-29.83, -15.95]). No significant publication bias was detected, and this result was stable in the sensitivity and subgroup analyses. Moreover, GLP-1RA treatment resulted in a greater reduction in VAT and SAT in the subgroup with a greater reduction in body weight. The absolute area reduction in VAT was significantly correlated with the reduction in body weight (r = 6.324, p = 0.035).ConclusionsGLP-1RA treatment leads to significant and similar absolute reductions in VAT and SAT, and the reduction in adipose tissues may be correlated with the reduction in body weight
Underwater High-Precision 3D Reconstruction System Based on Rotating Scanning
This paper presents an underwater high-precision line laser three-dimensional (3D) scanning (LLS) system with rotary scanning mode, which is composed of a low illumination underwater camera and a green line laser projector. The underwater 3D data acquisition can be realized in the range of field of view of 50° (vertical) × 360° (horizontal). We compensate the refraction of the 3D reconstruction system to reduce the angle error caused by the refraction of light on different media surfaces and reduce the impact of refraction on the image quality. In order to verify the reconstruction effect of the 3D reconstruction system and the effectiveness of the refraction compensation algorithm, we conducted error experiments on a standard sphere. The results show that the system’s underwater reconstruction error is less than 0.6 mm within the working distance of 140 mm~2500 mm, which meets the design requirements. It can provide reference for the development of low-cost underwater 3D laser scanning system
Weakly-Supervised Video Anomaly Detection with MTDA-Net
Weakly supervised anomalous behavior detection is a popular area at present. Compared to semi-supervised anomalous behavior detection, weakly-supervised learning both eliminates the need to crop videos and solves the problem of semi-supervised learning’s difficulty in handling long videos. Previous work has used graph convolution or self-attention mechanisms to model temporal relationships. However, these methods tend to model temporal relationships at a single scale and lack consideration of the aggregation problem for different temporal relationships. In this paper, we propose a weakly supervised anomaly detection framework, MTDA-Net, with emphasis on modeling different temporal relationships and enhanced semantic discrimination. To this end, we construct a new plug-and-play module, MTDA, which uses three branches, Multi-headed Attention (MHA), Temporal Shift (TS), and Dilated Aggregation (DA), to extract different temporal sequences. Specifically, the MHA branch can globally model the video information and project the features into different semantic spaces to enhance the expressiveness and discrimination of the features. The DA branch extracts temporal information of different scales via dilated convolution and captures the temporal features of local regions in the video. The TS branch can fuse the features of adjacent frames on a local scale and enhance the information flow. MTDA-Net can learn the temporal relationships between video segments on different branches and learn powerful video representations based on these relationships. The experimental results on the XD-Violence dataset show that MTDA-Net can significantly improve the detection accuracy of abnormal behaviors
Multiview Learning for Impervious Surface Mapping Using High-Resolution Multispectral Imagery and LiDAR Data
The use of multisource remote sensing data to obtain urban impervious surface has become a popular research topic. Multisource remote sensing data fusion techniques can provide object interpretation with a higher accuracy. However, most decision-level fusion methods make insufficient use of the complementary information and degree of association between similar object data. To fill this gap, in this article, we propose a dual-view learning fusion classification method (DvLF) based on multiview learning. First, DvLF uses cotraining algorithm to combine multiple data sources for accurate classification, extracting easy-to-classify area while separating difficult-to-classify regions for further analysis. Second, a canonical correlation analysis method is adopted to mine the degree of association of similar object data for constructing a subspace projection field of each object sample. The data in the difficult-to-classify regions are classified in the projection field of each object, and then the results of each classification are fused by voting. Finally, the classification results of the two regions are combined into the classification results of the whole image to achieve impervious surface mapping. The proposed method is applied to the dual-sensor (high-resolution image and LiDAR) Buffalo dataset and the dual-sensor (RGB and multispectral LiDAR) Houston dataset. The experimental results show that our method achieved a significant improvement in classification accuracy compared to other methods. The overall classification accuracy of this new DvLF fusion method on the Buffalo and Houston datasets is 83.35% and 88.84%, respectively, leading to accurate high-resolution impervious surface mapping
Reactions with Exotic Nuclei at Near and Sub-barrier Energies
We will introduce some new results derived recently by the nuclear reaction group at China Institute of Atomic Energy, on the properties of the optical model potentials of neutron-halo 6He system and reaction mechanisms induced by proton-drip line nucleus 17F at energies around the Coulomb barrier. For the study of optical model potentials of exotic nuclear system, we proposed a novel method, i.e., the transfer reaction method. This method has been applied to extract the optical potentials of neutron-halo 6He+209Bi system by measuring the one-proton transfer reactions induced by 7Li on a 208Pb target. A complete picture of threshold anomaly behavior was obtained in the 6He+209Bi system for the first time, where a decreasing trend of the depth of the imaginary potential is observed in the deep sub-barrier region, and the reaction threshold energy is extracted. Moreover, results show thatthe dispersion relation is not applicable for this exotic nuclear system. Reaction mechanisms of proton-rich nuclear systems 17F+89Y and 58Ni were also studied at energies around the Coulomb barrier. Continuum discretized coupled-channels calculations indicate that the coupling effects of the continuum states of 17F+89Y is not significant. Thanks to the employment of a powerful ionization-chamber based detector array, the reaction products over a large Z in the systems of 17F+58Ni can be identified clearly. The data analysis is undergoing