The influence of DC stray current on pipeline corrosion

DC stray current can cause severe corrosion on buried pipelines.In this study,firstly,we deduced the equation of DC stray current interference on pipelines.Next,the cathode boundary condition was discretized with pipe elements,and corresponding experiments were designed to validate the mathematical model.Finally,the numerical simulation program BEASY was used to study the corrosion effect of DC stray current that an auxiliary anode bed generated in an impressed current cathodic protection system.The effects of crossing angle,crossing distance,distance of the two pipelines,anode output current,depth,and soil resistivity were investigated.Our results indicate that pipeline crossing substantially affects the corrosion potential of both protected and unprotected pipelines.Pipeline crossing angles,crossing distances,and anode depths,our results suggest,have no significant influence.Decreasing anode output current or soil resistivity reduces pipeline corrosion gradually.A reduction of corrosion also occurs when the distance between two parallel pipelines increases.

Antitumor Effect of Apcin on Endometrial Carcinoma via p21-Mediated Cell Cycle Arrest and Apoptosis

Objective Endometrial carcinoma(EC)is a prevalent gynecological malignancy characterized by increasing incidence and mortality rates.This underscores the critical need for novel therapeutic targets.One such potential target is cell division cycle 20(CDC20),which has been implicated in oncogenesis.This study investigated the effect of the CDC20 inhibitor Apcin on EC and elucidated the underlying mechanism involved.Methods The effects of Apcin on EC cell proliferation,apoptosis,and the cell cycle were evaluated using CCK8 assays and flow cytometry.RNA sequencing(RNA-seq)was subsequently conducted to explore the underlying molecular mechanism,and Western blotting and coimmunoprecipitation were subsequently performed to validate the results.Animal studies were performed to evaluate the antitumor effects in vivo.Bioinformatics analysis was also conducted to identify CDC20 as a potential therapeutic target in EC.Results Treatment with Apcin inhibited proliferation and induced apoptosis in EC cells,resulting in cell cycle arrest.Pathways associated with apoptosis and the cell cycle were activated following treatment with Apcin.Notably,Apcin treatment led to the upregulation of the cell cycle regulator p21,which was verified to interact with CDC20 and consequently decrease the expression of downstream cyclins in EC cells.In vivo experiments confirmed that Apcin treatment significantly impeded tumor growth.Higher CDC20 expression was observed in EC tissue than in nonmalignant tissue,and increased CDC20 expression in EC patients was associated with shorter overall survival and progress free interval.Conclusion CDC20 is a novel molecular target in EC,and Apcin could be developed as a candidate antitumor drug for EC treatment.

Gas microchannel plate-pixel detector for X-ray polarimetry

POLAR-2 is a gamma-ray burst(GRB)polarimeter that is designed to study the polarization in GRB radiation emissions,aiming to improve our knowledge of related mechanisms.POLAR-2 is expected to utilize an on-board polarimeter that is sensitive to soft X-rays(2-10 keV),called low-energy polarization detector.We have developed a new soft X-ray polari-zation detector prototype based on gas microchannel plates(GMCPs)and pixel chips(Topmetal).The GMCPs have bulk resistance,which prevents charging-up effects and ensures gain stability during operation.The detector is composed of low outgassing materials and is gas-sealed using a laser welding technique,ensuring long-term stability.A modulation factor of 41.28%±0.64% is obtained for a 4.5 keV polarized X-ray beam.A residual modulation of 1.96%±0.58% at 5.9 keV is observed for the entire sensitive area.

Design and tests of the prototype a beam monitor of the CSR external target experiment

A prototype beam monitor was designed to provide tracking information for heavy-ion projectiles for the cool storage ring(CSR)external target experiment(CEE)at the Heavy Ion Research Facility in Lanzhou(HIRFL).High granularity and direct charge sensing are the main features of this device.It measures the beam position in a two-dimensional(2D)plane transverse to the beam direction on an event-by-event basis.The current design consists of two field cages inside a single vessel that operates independently and has electrical drift fields in orthogonal directions.Preliminary tests of the prototype were performed using a^(241)Am a source.The results show that a spatial resolution of less than 40μm and a time resolution of less than 600 ns can be achieved.

FGFR2 mutation in a Chinese family with unusual Crouzon syndrome

AIM：To describe the clinical characteristics with genetic lesions in a Chinese family with Crouzon syndrome. METHODS： All five patients from this family were included and received comprehensive ophthalmic and systemic examinations.Direct sequencing of the FGFR2 gene was employed for mutation identification.Crystal structure analysis was applied to analyze the structural changes associated with the substitution. RESULTS： All patients presented typical Crouzon features,including short stature,craniosynostosis,mandibular prognathism,shallow orbits with proptosis,and exotropia.Intrafamilial phenotypic diversities were observed.Atrophic optic nerves were exclusively detected in the proband and her son.Cranial magnetic resonance imaging implied a cystic lesion in her sellar and third ventricular regions.A missense mutation,FGFR2 p.Cys342 Trp,was found as disease causative.This substitution would generate conformational changes in the extracellular Ig-III domain of the FGFR-2 protein,thus altering its physical and biological properties.CONCLUSION： We describe the clinical presentations and genotypic lesions in a Chinese family with Crouzon syndrome.The intrafamilial phenotypic varieties in this family suggest that other genetic modifiers may also play a role in the pathogenesis of Crouzon syndrome.

Simulation and photoelectron track reconstruction of soft X-ray polarimeter

The soft X-ray polarimeter(SXP)is a detector with a wide energy range,large area,and large field of view.A SXP will be mounted on the Chinese Space Station and will mainly focus on detecting the polarization of transient soft X-ray(2–10 keV)sources,especially gamma-ray bursts(GRBs).In this work,a polarimeter detector unit is taken as an example,and Geant4 and Garfield++software are used to simulate the detection efficiency and track production.An improved track reconstruction algorithm is proposed and used to reconstruct two-dimensional images of the tracks.In this method,the initial emission angle of photoelectrons is reconstructed from the initial part of the track by shortening or extending the initial part of the track until the remaining track is straight,and the number of pixels is within an adjustable threshold.The modulation factor of the photoelectronic tracks after reconstruction reaches approximately 57%in the photon energy range of 7–10 keV.

Electronics system for the cosmic X-ray polarization detector

This study presents an electronics system for cosmic X-ray polarization detection(CXPD).The CXPD was designed as a high-sensitivity soft X-ray polarimeter with a measurement energy range of 2-10 keV carried by a CubeSat.A stable and functionally complete electronics system under power and space constraints is a key challenge.The complete CXPD electronics system(CXPDES)comprises hardware and firmware.CXPDES adopts a three-layer electronic board structure based on functionality and available space.Two gas pixel detectors(GPDs)were placed on the top layer board,and CXPDES provided the GPDs with voltages up to-4000 V.Each GPD signal was digitized,compressed,encoded,and stored before being transmitted to the ground.The CXPDES provided stable and high-speed communication based on a scheme that separated command and data transmission,and it supports the CXPDES in-orbit upgrade.In addition,environmental monitors,silicon photomultiplier(SiPM)triggers,power management,GPDs configuration,and mode switches were included in the overall operating logic of the CXPDES.The results obtained by testing the CXPDES showed that it satisfied all the requirements of CXPD.The CXPDES provides design experience and technological readiness for future large-area X-ray polarimetry missions.

Design of detector to monitor the Bragg peak location of carbon ions by means of prompt γ-ray measurements with Geant4

Real-time monitoring of the Bragg peak location of carbon ions is urgently required for the quality control of hadron therapy. In this study, we design an annular detector to monitor the Bragg peak location of carbon ions with Geant4 simulation. This 360° surrounding structure has a high detection efficiency for the small-dose situation. The detector consists of a multilayered collimator system and an Na I scintillator for prompt gamma counting. The multilayered collimator includes a lead layer to prevent unwanted gammas and the paraffin and boron carbide layers to moderate and capture fast neutrons. An inclination of the detector further diminishes the background signal caused by neutrons. The detector, with optimized parameters, is applicable to carbon ions of different energies. In addition, the scintillator is replaced by an improved EJ301 organic liquid scintillator to discriminate gammas and neutrons. Inserting thin Fe slices into the liquid scintillator improves the energy deposition efficiency. The Bragg peak location of 200 Me V/u carbon ions can be monitored by prompt gamma detection with the improved liquid scintillator.

Probing multi-physical process and deformation mechanism of a largescale landslide using integrated dual-source monitoring

The implementation of isolated heterologous monitoring systems for spatially distant borehole deployments often comes with substantial equipment costs,which can limit the effectiveness of geohazard mitigation and georisk management efforts.To address this,we have developed a novel monitoring system that integrates fiber Bragg grating(FBG)and microelectromechanical system(MEMS)techniques to capture soil moisture,temperature,sliding resistance,strain,surface tilt,and deep-seated inclination.This system enables real-time,simultaneous data acquisition and cross-validation analyses,offering a costeffective solution for monitoring critical parameters in geohazard-prone areas.We successfully applied this integrated monitoring system to the Xinpu landslide,an active super-large landslide located in the Three Gorges Reservoir Area(TGRA)of China.The resulting strain profile confirmed the presence of two shallow secondary sliding surfaces at depths of approximately 7 m and 12 m,respectively,in addition to the deep-seated sliding surface at a depth of28 m.The lower secondary sliding surface was activated by extreme precipitation,while the upper one was primarily driven by significant changes in reservoir water levels and secondarily triggered by concentrated rainfalls.Anti-slide piles have remarkably reinforced the upper moving masses but failed to control the lower ones.The gap between the pile heads and the soil amplified the rainwater erosion effect,creating a preferential channel for rainwater infiltration.Multi-physical measurements revealed a mixture of seepage-driven and buoyancy-driven behaviors within the landslide.This study offers an integrated dual-source multi-physical monitoring paradigm that enables collaborative management of multiple crucial boreholes on a large-scale landslide,and contributes to the evaluation and improvement of engineering measures in similar geological settings.