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A black hole on a three-brane in five-dimensional spacetime was predicted by Dadhich, Maartens, Papadopoulos and Rezania (DMPR). In order to reveal some signatures for observations, we investigate a timelike particle’s motion around the DMPR brane-world black holes. We find that, both in the innermost stable circular orbits (ISCO) and the marginally bound orbits (MBO), the particle’s angular momentum and its radius decrease with the increase of Q , where Q is a tidal charge parameter and may be negative and positive in the brane-world black holes. From these results, the corresponding periodic orbits with different energy levels are analyzed numerically by employing a taxonomy, which is related to the adiabatic inspiral regime in the gravitational wave radiation. It clearly shows that a rational number defined by the taxonomy increases with the particle’s energy. In addition, periodic orbits with Q < 0 in the DMPR brane-world black holes have higher energy in comparison to the ones with Q > 0 and in the Schwarzschild black holes. Our results might provide hints for distinguishing the DMPR brane-world black holes from other black holes by the timelike particle’s periodic orbits in the future.

We investigate neutral and charged test particles’ motions around quantum-corrected Schwarzschild black holes immersed in an external magnetic field. Taking the innermost stable circular orbits of neutral timelike particles into account, we find that the black holes can mimic different ranges of the Kerr black hole’s spin |a/M| from 0.15 to 0.99. Our analysis of charged test particles’ motions suggests that the values of the angular momentum l and the energy E2 are slightly higher than Schwarzschild black holes. The allowed regions of the (l,E2) demonstrate that the critical energy Ec2 divides the charged test particle’s bounded trajectory into three types. With the help of a Monte Carlo method, we study the charged particles’ probabilities of falling into the black holes and find that the probability density function against l depends on the signs of the particles’ charges. Finally, the epicyclic frequencies of the charged particles are considered with respect to the observed twin peak quasi-periodic oscillations frequencies. Our results might provide hints for distinguishing quantum-corrected Schwarzschild black holes from Schwarzschild ones by using the dynamics of charged test particles around the strong gravitational field.

We investigate the dynamics of neutral timelike particles around a hairy black hole in Horndeski’s theory, which is characterized by a coupling parameter with the dimension of length. With deriving the particles’ relativistic periastron precessions, a preliminary bound on the hairy black hole is obtained by using the result of the S2 star’s precession with GRAVITY. It is tighter than the previous result constrained by the shadow size from EHT observations of M87* by about 3–4 orders of magnitude. We also analyse the particles’ periodic motions around the hole in the strong gravitational field. It clearly shows that small variations in the coupling parameter can make the neutral particles’ motions back and forth from the quasi-periodic orbits to the periodic orbits or no bound orbit. Our present work might provide hints for distinguishing the hairy black hole in Horndeski’s theory from the classical hole by using the particles’ dynamics in the strong gravitational field.

The perceived inability of climate change mitigation goals alone to mobilize sufficient climate change mitigation efforts has, among other factors, led to growing research on the co-benefits of reducing greenhouse gas (GHG) emissions. This study conducts a systematic review (SR) of the literature on the co-benefits of mitigating GHG emissions resulting in 1554 papers. We analyze these papers using bibliometric analysis, including a keyword co-occurrence analysis. We then iteratively develop and present a typology of co-benefits, mitigation sectors, geographic scope, and methods based on the manual double coding of the papers resulting from the SR. We find that the co-benefits from GHG mitigation that have received the largest attention of researchers are impacts on ecosystems, economic activity, health, air pollution, and resource efficiency. The co-benefits that have received the least attention include the impacts on conflict and disaster resilience, poverty alleviation (or exacerbation), energy security, technological spillovers and innovation, and food security. Most research has investigated co-benefits from GHG mitigation in the agriculture, forestry and other land use (AFOLU), electricity, transport, and residential sectors, with the industrial sector being the subject of significantly less research. The largest number of co-benefits publications provide analysis at a global level, with relatively few studies providing local (city) level analysis or studying co-benefits in Oceanian or African contexts. Finally, science and engineering methods, in contrast to economic or social science methods, are the methods most commonly employed in co-benefits papers. We conclude that given the potential mobilizing power of understudied co-benefits (e.g. poverty alleviation) and local impacts, the magnitude of GHG emissions from the industrial sector, and the fact that Africa and South America are likely to be severely affected by climate change, there is an opportunity for the research community to fill these gaps.

Recently, Zhang et al. [Eur. Phys. J. C 84, 381, https://doi.org/10.1140/epjc/s10052-024-12723-8 (2024)] constrained the Yukawa correction in the general free scalar–tensor gravity by borrowing the measured values of the parametrized post-Newtonian (PPN) parameters γ - 1 = ( 2.1 ± 2.3 ) × 10 - 5 and β - 1 = ( - 4.1 ± 7.8 ) × 10 - 5 in the Solar System tests. They firstly defined two PPN parameters γ ( r ) and β ( r ) in the gravity, which depend on the radial distance r and include the Yukawa-type parameters. Then, by comparing between the experiments’ results of two PPN parameters and their γ ( r ) and β ( r ) , the authors claimed that they gave the tightest bound on the gravity by the Cassini tracking experiment. However, we find their approach is not rigorous. In this paper, corresponding astronomical experiments have been physically modelled by considering the lightlike and the timelike geodesics in the general free scalar–tensor gravity. Contrary to the wrong results in Zhang et al.’s work, it is shown that the Cassini tracking experiment is insensitive to the general free scaler–tensor gravity. Furthermore, we also find that the time delay and the light deflection are all independent of the gravity. Due to an additional Yukawa-type advance in the periastron shift, we derive very much improved bounds on the Yukawa-type parameters of this gravity.

Health education can help patients engage in evidence-based healthy behaviors, and the construction of smart hospitals can promote accurate video-based health education for patients. However, little is known about the clinical practice of personalized video-based health education for ischemic stroke patients in China. We investigated video-based health education viewing frequency and relevant impact factors among patients with ischemic stroke. Data were collected from 1,569 ischemic stroke patients admitted to the Vascular Neurology Ward of a hospital in China between 01/08/2020 and 31/12/2022, to analyze their use of personalized video-based health education. The video-based integrated management system used in our hospital can facilitate keyword extraction, thus achieving accurate and personalized video-based health education and promotion. Data, including demographic and disease-related data, viewing frequency, total viewing amount and viewing frequency for each dimension, were extracted from the hospital's video integrated management system and medical system. Univariate analysis and multiple linear regression helped identify factors associated with whether the patients viewed personalized video-based health education materials. A total of 1569 patients were included (age = 58.72 ± 13.50 years old; 1177 (75.0%) males). Diet rehabilitation education was the most frequently viewed personalized video-based health education dimension; the average viewing frequency was 2.30 ± 1.15 times/day during an average hospitalization of 12.55 ± 4.12 days. According to the multivariable analysis, factors associated with a reduced likelihood of viewing the personalized video-based health education materials (P < 0.05) included visual and hearing impairment, longer hospital stays, and speech impairment. In contrast, compared to self-paying patients, individuals who were covered by medical insurance or received free medical service were more likely to view the personalized video-based health education materials. A personalized video-based health education program with a keyword extraction function can help achieve accurate and personalized video-based health education and promotion and effectively improve patients' health-education participation rate.

The human neonatal cerebellum is one-fourth of its adult size yet contains the blueprint required to integrate environmental cues with developing motor, cognitive and emotional skills into adulthood. Although mature cerebellar neuroanatomy is well studied, understanding of its developmental origins is limited. In this study, we systematically mapped the molecular, cellular and spatial composition of human fetal cerebellum by combining laser capture microscopy and SPLiT-seq single-nucleus transcriptomics. We profiled functionally distinct regions and gene expression dynamics within cell types and across development. The resulting cell atlas demonstrates that the molecular organization of the cerebellar anlage recapitulates cytoarchitecturally distinct regions and developmentally transient cell types that are distinct from the mouse cerebellum. By mapping genes dominant for pediatric and adult neurological disorders onto our dataset, we identify relevant cell types underlying disease mechanisms. These data provide a resource for probing the cellular basis of human cerebellar development and disease. SPLiT-seq single-nucleus RNA sequencing of the developing human cerebellum reveals cell-type complexities and prolonged maturation compared to mouse with important disease implications.

Chirality describes mirror symmetry breaking in geometric structures or certain physical quantities. The interaction between chiral structure and chiral light provides a rich collection of means for studying the chirality of substances. Recently, optical chiral metasurfaces have emerged as planar or quasi-planar photonic devices composed of subwavelength chiral unit cells, offering distinct appealing optical responses to circularly polarized light with opposite handedness. The chiroptical effects in optical metasurfaces can be manifested in the absorption, scattering, and even emission spectra under the circular polarization bases. A broadband chiroptical effect is highly desired for many passive chiral applications such as pure circular polarizers, chiral imaging, and chiral holography, in which cases the resonances should be avoided. On the other hand, resonant chiroptical responses are particularly needed in many situations requiring strong chiral field enhancement such as chiral sensing and chiral emission. This article reviews the latest research on both broadband and resonant chiral metasurfaces. First, we discuss the basic principle of different types of chiroptical effects including 3D/2D optical chirality and intrinsic/extrinsic optical chirality. Then we review typical means for broadband chiral metasurfaces, and related chiral photonic devices including broadband circular polarizers, chiral imaging and chiral holography. Then, we discuss the interaction between chiral light and matter enhanced by resonant chiral metasurfaces, especially for the chiral bound states in the continuum metasurfaces with ultra-high quality factors, which are particularly important for chiral molecule sensing, and chiral light sources. In the final section, the review concludes with an outlook on future directions in chiral photonics.

As an extension of the previous work on Solar System tests of an effective loop quantum black hole, and an attempt to find more stringent constraints on the loop quantum effect, we study its effects on physical experiments and astronomical observations conducted in the Solar System. By considering light deflection, time delay, and Cassini tracking experiments at the second post-Newtonian (2PN) order for light propagation, we find that the parametrized post-Newtonian (PPN) parameter γ in the black hole strictly equals 1. Using supplementary advances for Mercury taken from the EPM2011 and INPOP10a ephemerides, we derive much improved bounds on the black hole, which strengthen constraints on the loop quantum effect by ten times. Since such quantum effects are more likely to be observable in strong-field regimes, we estimate a preliminary bound on the loop quantum effect in these regimes based on results from EHT observations, discuss future prospects of other tests (e.g., extreme mass-ratio inspiral systems), and compare these strong-field constraints with those from the Solar System. It is worth noting that primordial black holes might provide a promising way to identify the loop quantum effect. Solar system experiments are probably not applicable for probing the quantum effect signal.

AbstractObjectiveTo determine whether a single low dose of esketamine administered after childbirth reduces postpartum depression in mothers with prenatal depression.DesignRandomised, double blind, placebo controlled trial with two parallel arms.SettingFive tertiary care hospitals in China, 19 June 2020 to 3 August 2022.Participants364 mothers aged ≥18 years who had at least mild prenatal depression as indicated by Edinburgh postnatal depression scale scores of ≥10 (range 0-30, with higher scores indicating worse depression) and who were admitted to hospital for delivery.InterventionsParticipants were randomly assigned 1:1 to receive either 0.2 mg/kg esketamine or placebo infused intravenously over 40 minutes after childbirth once the umbilical cord had been clamped.Main outcome measuresThe primary outcome was prevalence of a major depressive episode at 42 days post partum, diagnosed using the mini-international neuropsychiatric interview. Secondary outcomes included the Edinburgh postnatal depression scale score at seven and 42 days post partum and the 17 item Hamilton depression rating scale score at 42 days post partum (range 0-52, with higher scores indicating worse depression). Adverse events were monitored until 24 hours after childbirth.ResultsA total of 364 mothers (mean age 31.8 (standard deviation 4.1) years) were enrolled and randomised. At 42 days post partum, a major depressive episode was observed in 6.7% (12/180) of participants in the esketamine group compared with 25.4% (46/181) in the placebo group (relative risk 0.26, 95% confidence interval (CI) 0.14 to 0.48; P<0.001). Edinburgh postnatal depression scale scores were lower in the esketamine group at seven days (median difference −3, 95% CI −4 to −2; P<0.001) and 42 days (−3, −4 to −2; P<0.001). Hamilton depression rating scale scores at 42 days post partum were also lower in the esketamine group (−4, −6 to −3; P<0.001). The overall incidence of neuropsychiatric adverse events was higher in the esketamine group (45.1% (82/182) v 22.0% (40/182); P<0.001); however, symptoms lasted less than a day and none required drug treatment.ConclusionsFor mothers with prenatal depression, a single low dose of esketamine after childbirth decreases major depressive episodes at 42 days post partum by about three quarters. Neuropsychiatric symptoms were more frequent but transient and did not require drug intervention.Trial registrationClinicalTrials.gov NCT04414943.