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"Long, Xi"
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Precision cosmology from future lensed gravitational wave and electromagnetic signals
The standard siren approach of gravitational wave cosmology appeals to the direct luminosity distance estimation through the waveform signals from inspiralling double compact binaries, especially those with electromagnetic counterparts providing redshifts. It is limited by the calibration uncertainties in strain amplitude and relies on the fine details of the waveform. The Einstein telescope is expected to produce 10
4
–10
5
gravitational wave detections per year, 50–100 of which will be lensed. Here, we report a waveform-independent strategy to achieve precise cosmography by combining the accurately measured time delays from strongly lensed gravitational wave signals with the images and redshifts observed in the electromagnetic domain. We demonstrate that just 10 such systems can provide a Hubble constant uncertainty of 0.68% for a flat lambda cold dark matter universe in the era of third-generation ground-based detectors.
Gravitational wave sources can be used as cosmological probes through a direct distance luminosity relation. Here, the authors demonstrate that the time delay between lensed gravitational wave signals and their electromagnetic counterparts can reduce the uncertainty in the Hubble constant.
Journal Article
New Dawn for Atherosclerosis: Vascular Endothelial Cell Senescence and Death
Endothelial cells (ECs) form the inner linings of blood vessels, and are directly exposed to endogenous hazard signals and metabolites in the circulatory system. The senescence and death of ECs are not only adverse outcomes, but also causal contributors to endothelial dysfunction, an early risk marker of atherosclerosis. The pathophysiological process of EC senescence involves both structural and functional changes and has been linked to various factors, including oxidative stress, dysregulated cell cycle, hyperuricemia, vascular inflammation, and aberrant metabolite sensing and signaling. Multiple forms of EC death have been documented in atherosclerosis, including autophagic cell death, apoptosis, pyroptosis, NETosis, necroptosis, and ferroptosis. Despite this, the molecular mechanisms underlying EC senescence or death in atherogenesis are not fully understood. To provide a comprehensive update on the subject, this review examines the historic and latest findings on the molecular mechanisms and functional alterations associated with EC senescence and death in different stages of atherosclerosis.
Journal Article
The Origin Channels of Hierarchical Binary Black Hole Mergers in the LIGO–Virgo–KAGRA O1, O2, and O3 Runs
We infer the origin channels of hierarchical mergers observed in the LIGO–Virgo–KAGRA (LVK) O1, O2, and O3 runs using a hierarchical Bayesian analysis under a parametric population model. By assuming the active galactic nucleus (AGN) disk and nuclear star cluster (NSC) channels, we find that NSCs likely dominate the hierarchical merger rate in the Universe, corresponding to a fraction of fNSC=0.87−0.29+0.10 at 90% credible intervals in our fiducial model; AGN disks may contribute up to nearly half of hierarchical mergers detectable with LVK, specifically fdet,AGN=0.34−0.26+0.38 . We investigate the impact of the escape speed, along with other population parameters on the branching fraction, suggesting that the mass, mass ratio, and spin of the sources play significant roles in population analysis. We show that hierarchical mergers constitute at least ∼10% of the gravitational-wave events detected by LVK during the O1–O3 runs. Furthermore, we demonstrate that it is challenging to effectively infer detailed information about the host environment based solely on the distribution of black hole merger parameters if multiple formation channels are considered.
Journal Article
Air pollution could drive global dissemination of antibiotic resistance genes
Antibiotic-resistant pathogens pose a significant threat to human health. Several dispersal mechanisms have been described, but transport of both microbes and antibiotic resistance genes (ARGs) via atmospheric particles has received little attention as a pathway for global dissemination. These atmospheric particles can return to the Earth’s surface via rain or snowfall, and thus promote long-distance spread of ARGs. However, the diversity and abundance of ARGs in fresh snow has not been studied and their potential correlation with particulate air pollution is not well explored. Here, we characterized ARGs in 44 samples of fresh snow from major cities in China, three in North America, and one in Europe, spanning a gradient from pristine to heavily anthropogenically influenced ecosystems. High-throughput qPCR analysis of ARGs and mobile genetic elements (MGEs) provided strong indications that dissemination of ARGs in fresh snow could be exacerbated by air pollution, severely increasing the health risks of both air pollution and ARGs. We showed that snowfall did effectively spread ARGs from point sources over the Earth surface. Together our findings urge for better pollution control to reduce the risk of global dissemination of antibiotic resistance genes.
Journal Article
Calculation of a Dynamical Substitute for the Real Earth–Moon System Based on Hamiltonian Analysis
The Earth–Moon libration points no longer exhibit the dynamical characteristics of “equilibrium points” due to perturbation effects when applying the ephemeris model. By decoupling the forced motions within the ephemeris model and computing the dynamical substitute trajectories, we can reconstruct a dynamical system that recovers the “equilibrium points” feature. Diverging from the conventional analytical approach rooted in the framework of Newtonian mechanics, this paper presents a novel method for calculating dynamical substitute based on the Hamiltonian mechanics framework. First, the Hamiltonian equations for the ephemeris model are formulated. Subsequently, the problem of decoupling forced motions is reformulated as solving a nonautonomous differential equation through canonical transformations. Then, an iterative method based on frequency analysis is employed for the computation. Eventually, approximate analytical solutions for five libration points over a 360 yr period are provided. Simulation results demonstrate that the computed approximate analytical solutions are in excellent agreement with the numerical integration results derived from the ephemeris model, thereby validating the efficacy of the proposed method. The Hamiltonian dynamical system derived herein enables the analysis of nonlinear central manifold motions via canonical transformations, facilitating the construction of higher-order analytical solutions for libration point orbits. This framework also provides a robust foundation for exploring characterization parameters of libration point orbits within the real Earth–Moon system.
Journal Article
The Use of Binary Black Holes Merging in Active Galactic Nuclei Disks for Hubble Constant Measurements
We study the impact of environmental effects on the measurement of the Hubble constant (H0) from gravitational-wave (GW) observations of binary black hole mergers residing in active galactic nuclei (AGNs) near the central supermassive black hole. Using the potential hierarchical triple merger candidate GW190514–GW190521 in AGN J124942.3+344929 with its potential electromagnetic counterpart ZTF19abanrhr as a multimessenger case study, we demonstrate that environmental effects can be negligible for mergers at approximately tens to hundreds of Schwarzschild radii from the supermassive black hole. We find H0=40.9−8.9+19.3kms−1Mpc−1 (median and 68% credible interval) under a flat prior and flat ΛCDM cosmology. Incorporating GW170817 prior information improves constraints to H0=68.8−6.0+7.7kms−1Mpc−1 . We suggest that, in general, AGN environments could serve as viable laboratories for cosmological studies from GW observations where environmental effects remain below detection thresholds.
Journal Article
Transcriptional Regulation of Macrophages Polarization by MicroRNAs
Diversity and plasticity are the hallmarks of cells from the monocyte-macrophage lineage. Macrophages undergo classical M1 or alternative M2 activation in response to the microenvironment signals. Several transcription factors, such as peroxisome proliferator-activated receptors, signal transducers and activators of transcription, CCAAT-enhancer-binding proteins, interferon regulatory factors, Kruppel-like factors, GATA binding protein 3, nuclear transcription factor-κB, and c-MYC, were found to promote the expression of specific genes, which dictate the functional polarization of macrophages. Importantly, these transcription factors can be regulated by microRNAs (miRNAs), a group of small non-coding RNAs, which regulate gene expression through translation repression or mRNA degradation. Recent studies have also revealed that miRNAs control macrophage polarization by regulating transcription factors in response to the microenvironment signals. This review will summarize recent progress of miRNAs in the transcriptional regulation of macrophage polarization and provide the insights into the development of macrophage-centered diagnostic and therapeutic strategies.
Journal Article
I am not a Sportsman: the characteristics of identity construction in Traditional Chinese Martial Arts groups
Against the backdrop of sports globalization, Chinese martial arts are influenced by the integration of diverse cultures, making the identity of martial arts communities a topic worthy of attention. Although Chinese scholars have conducted extensive discussions on the issues of Chinese martial arts communities, most of these discussions have been based on reviews and quantitative methods. There is a lack of exploration into the construction of identity among traditional Chinese martial arts communities and the factors affecting identity recognition, as well as a lack of focus on internal group conflicts. The purpose of this paper is to survey how Chinese martial artists define their own identity and how factors inside and outside the group influence their perception of identity. The study adopts grounded theory based on constructivist methodology, interviewing 28 participants (15 traditional martial artists, 6 competitive martial athletes, 5 decision-makers and managers, and 2 university researchers). The research results have established a theoretical model of identity construction based on traditional martial arts communities, describing the subjective interpretation of the complex process by which traditional Chinese martial arts communities form their identity definition. The model demonstrates the impact of individual, intra-group, and extra-group dimensions on identity recognition. The foundation of identity construction for traditional Chinese martial arts communities is the individual's perception of martial arts, while factors inside and outside the group have a shaping effect on the identity recognition of group members. The study reveals that the process of identity construction is complex and highly related to cultural influences, rather than being singular. This research helps stakeholders better understand the characteristics of the identity of traditional Chinese martial arts communities and provides a foundation for future research on Chinese martial arts communities and cultural integration.
Journal Article
The Nature of Gravitational Wave Events with Host Environment Escape Velocities
We propose a novel method to probe the parameters and origin channels of gravitational wave events using the escape velocities of their host environments. This method could lead to more convergent posterior distributions offering additional insights into the physical properties, formation, and evolution of the sources. The method provides more accurate parameter estimation for events that represent previous mergers in the hierarchical triple merger scenario and is valuable for the search for such mergers with third-generation ground-based detectors. To demonstrate this approach, we take six recently identified events in LIGO–Virgo–KAGRA (LVK) data, considered as potential previous mergers in hierarchical triple mergers, as examples. The use of escape velocities results in posterior spin distributions that are concentrated near zero, aligning with the expected birth spins of first-generation black holes formed from the collapse of stars. The uncertainty in the posterior primary mass distribution is significantly reduced comparing with the LVK distributions, especially for events modeled under the assumption of a globular cluster (GC) origin scenario. We rule out the possibility that GW190512, GW170729, and GW190708 originate from GCs as previous mergers in the hierarchical triple merger scenario.
Journal Article