The Correlated Multi-color Optical Variations of BL Lac Object S5 0716+714

S5 0716+714 is a well-studied BL Lac object in the sky. Verifying the existence of correlations among the flux variations in different bands serves as an important tool to investigate the emission processes. To examine the possible existence of a lag between variations in different optical bands on this source, we employ a discrete correlation function (DCF) analysis on the light curves. In order to obtain statistically meaningful values for the cross-correlation time lags and their related uncertainties, we perform Monte Carlo simulations called "flux redistribution/random subset selection" (FR/RSS). Our analysis confirms that the variations in different optical light curves are strongly correlated. The time lags show a hint of the variations in high frequency band leading those in low frequency band of the order of a few minutes.Comment: 6 pages, 5 figures, 3 tables. This paper has been accepted for publication in PASA

Dynamics Modeling of a Delta Robot with Telescopic Rod for Torque Feedforward Control

This paper presents dynamics modeling of a Delta robot with three revolute legs and a telescopic rod. Firstly, two generalized coordinate systems are established to describe the relationship between the movement of the telescopic rod and the position of the moving platform, and the telescopic rod system kinematics are established through singularity analysis. Secondly, taking the telescopic rod as the research object, the corresponding dynamics model is established using the Euler–Lagrange method. Moreover, this paper proposes a method to convert the force exerted by the telescopic rod motion on the moving platform into actuator torques. Thirdly, the dynamics model of the Delta robot with a telescopic rod is established, and numerical simulations are performed to demonstrate this approach. Finally, the influence of the telescopic rod on the actuator torques is verified using an experiment. A comparison is drawn between the two dynamics models used in torque feedforward control to validate the proposed dynamics model

Dynamics Modeling of a Delta Robot with Telescopic Rod for Torque Feedforward Control

This paper presents dynamics modeling of a Delta robot with three revolute legs and a telescopic rod. Firstly, two generalized coordinate systems are established to describe the relationship between the movement of the telescopic rod and the position of the moving platform, and the telescopic rod system kinematics are established through singularity analysis. Secondly, taking the telescopic rod as the research object, the corresponding dynamics model is established using the Euler–Lagrange method. Moreover, this paper proposes a method to convert the force exerted by the telescopic rod motion on the moving platform into actuator torques. Thirdly, the dynamics model of the Delta robot with a telescopic rod is established, and numerical simulations are performed to demonstrate this approach. Finally, the influence of the telescopic rod on the actuator torques is verified using an experiment. A comparison is drawn between the two dynamics models used in torque feedforward control to validate the proposed dynamics model

Heterogeneous Mercury Oxidation by HCl over CeO₂ Catalyst: Density Functional Theory Study

CeO₂-based catalysts have been regarded as potential materials for Hg removal due to high catalytic performance, nontoxicity, and low cost. Density functional theory calculations were performed to investigate the mercury oxidation mechanism by HCl over a CeO₂ catalyst. The thermodynamic stability analysis suggests that the stoichiometric CeO₂(111) is the most stable surface. The protonated CeO₂ surfaces takes place at low oxygen partial pressures, and the chlorinated CeO₂ surfaces can stably exist under low HCl concentrations. The adsorption energies and geometries show that Hg⁰ is physically adsorbed on oxygen sites of the CeO₂(111) surface and HCl is chemically adsorbed on the CeO₂(111) surface. HCl can dissociate on the CeO₂(111) surface with a low barrier. The Hg oxidation is most likely to proceed with the Eley–Rideal mechanism at the first step (Hg → HgCl), followed by the Langmuir–Hinshelwood mechanism at the second step (HgCl → HgCl₂). In the whole Hg oxidation reaction, the formation of HgCl₂ is the rate-determining step. The low energy barriers for the oxidation reaction of Hg on CeO₂ make it an attractive alternative catalyst for Hg oxidation

Targeting Hippo pathway: A novel strategy for Helicobacter pylori-induced gastric cancer treatment

The Hippo pathway plays an important role in cell proliferation, apoptosis, and differentiation; it is a crucial regulatory pathway in organ development and tumor growth. Infection with Helicobacter pylori (H. pylori) increases the risk of developing gastric cancer. In recent years, significant progress has been made in understanding the mechanisms by which H. pylori infection promotes the development and progression of gastric cancer via the Hippo pathway. Exploring the Hippo pathway molecules may yield new diagnostic and therapeutic targets for H. pylori-induced gastric cancer. The current article reviews the composition and regulatory mechanism of the Hippo pathway, as well as the research progress of the Hippo pathway in the occurrence and development of H. pylori-related gastric cancer, in order to provide a broader perspective for the study and prevention of gastric cancer

Facile Synthesis of β-Lactoglobulin-Functionalized Reduced Graphene Oxide and Trimetallic PtAuPd Nanocomposite for Electrochemical Sensing

The use of graphene has leapt forward the materials field and the functional modification of graphene has not stopped. In this work, β-lactoglobulin (BLG) was used to functionalize reduced graphene oxide (RGO) based on its amphiphilic properties. Also, trimetallic PtAuPd nanoparticles were reduced to the surface of BLG-functionalized RGO and formed BLG-PtAuPd-RGO nanocomposite using facile synthesis. Transmission electron microscopy, energy-dispersive X-ray spectroscopy and Fourier transform infrared spectra were used to characterize the nanocomposite. Electrocatalytic analysis was evaluated through cyclic voltammetry and chronoamperometry methods. We developed a glucose sensor by fabricating GOD-BLG-PtAuPd-RGO/glassy carbon (GC) electrode. It presented a remarkable sensitivity of 63.29 μA mM−1 cm−2 (4.43 μA mM−1), a wider linear range from 0.005 to 9 mM and a lower detection limit of 0.13 μM (S/N = 3). Additionally, the glucose sensor exhibited excellent testing capability in human serum samples

Quantitative Analysis of Retinal Vasculature in Rhegmatogenous Retinal Detachment Based on Ultra-Widefield Fundus Imaging

PurposeTo quantitatively analyze retinal vascular morphological features, such as vascular density, caliber, and tortuosity, in rhegmatogenous retinal detachment (RRD). MethodsA total of 244 patients with RRD and 400 healthy controls (HC) were included. Retinal fundus images were collected using OPTOS PLC Daytona P200T. Retinal images were divided into RRD and non-RRD regions of interest (ROIs). All visible retinal fundus vessels were then extracted mainly based on edge detection within ROI to form the whole-vascular image. Retinal vasculature parameters, such as vascular density, caliber, and tortuosity, were calculated. ResultsFor the absolute density, the mean rank (MR) value of normal controls was significantly higher than that in non-RRD (p < 0.001). A consistent tendency of significant vascular density was increased from non-RRD to RRD (p < 0.001). The average and median diameters of normal controls were both significantly larger than RRD (p < 0.001). The average and median diameters were also appeared significantly thinner in non-RRD. Unweighted and width-inversely-weighted vascular tortuosity in RRD and non-RRD comparison exhibited non-significant differences. All types of tortuosity calculated from HC were significantly larger (p < 0.001) in values compared to RRD. All types of tortuosity values of HC were significantly higher than non-RRD. Compared with non-RRD, RRD was significantly larger in area-weighted, length-weighted, and width-weighted vascular tortuosity. ConclusionsThis study showed that RRD affects both the quantity and morphology of retinal vasculature, such as RRD and non-RRD areas. Smaller average and medium vascular diameters and tortuosity values were found in RRD. However, the absolute vascular density, the average and median diameter, and tortuosity values were also reduced in non-RRD although the retina is still attached. This work indicates that RRD may affect the retinal vasculature beyond the detached retina