Simulation and experimental comparison of the performance of four-corner-readout plastic scintillator muon-detector system

Cosmic-ray muons are highly penetrating background-radiation particles found in natural environments.In this study,we develop and test a plastic scintillator muon detector based on machine-learning algorithms.The detector underwent muon position-resolution tests at the Institute of Modern Physics in Lanzhou using a multiwire drift chamber(MWDC)experimental platform.In the simulation,the same structural and performance parameters were maintained to ensure the reliability of the simulation results.The Gaussian process regression(GPR)algorithm was used as the position-reconstruction algorithm owing to its optimal performance.The results of the Time Difference of Arrival algorithm were incorporated as one of the features of the GPR model to reconstruct the muon hit positions.The accuracy of the position reconstruction was evaluated by comparing the experimental results with Geant4 simulation results.In the simulation,large-area plastic scintillator detectors achieved a position resolution better than 20 mm.In the experimental-platform tests,the position resolutions of the test detectors were 27.9 mm.We also analyzed factors affecting the position resolution,including the critical angle of the total internal reflection of the photomultiplier tubes and distribution of muons in the MWDC.Simulations were performed to image both large objects and objects with different atomic numbers.The results showed that the system could image high-and low-Z materials in the constructed model and distinguish objects with significant density differences.This study demonstrates the feasibility of the proposed system,thereby providing a new detector system for muon-imaging applications.

Effect of microalloying on wettability and interface characteristics of Zr-based bulk metallic glasses with W substrate

The infiltration casting method is widely employed for the preparation of ex-situ composite materials.However,the production of composite materials using this method must necessitates a comprehensive understanding of the wettability and interface characteristics between the reinforcing phase and the bulk metallic glasses(BMGs).This work optimized the composition of Zr-based BMGs through microalloying methods,resulting in a new set of Zr-based BMGs with excellent glass-forming ability.Wetting experiments between the Zr-based BMGs melts and W substrates were conducted using the traditional sessile drop method,and the interfaces were characterized utilizing a scanning electron microscope(SEM)equipped with energy dispersive X-ray spectroscopy(EDS).The work demonstrates that the microalloying method substantially enhances the wettability of the Zr-based BMGs melt.Additionally,the incorporation of Nb element impedes the formation of W-Zr phases,but the introduction of Nb element does not alter the extent of interdiffusion between the constituent elements of the amorphous matrix and W element,indicating that the influence of Nb element on the diffusion of individual elements is minute.

In situ non-destructive measurement of Josephson junction resistance using fritting contact technique

Conventional four-probe methods for measuring the resistance of Josephson junctions can damage superconducting thin films,making them unsuitable for frequency measurements of superconducting qubits.In this study,we present a custom probe station measurement system that employs the fritting contact technique to achieve in situ,non-destructive measurements of Josephson junction resistance.Our experimental results demonstrate that this method allows for accurate prediction of qubit frequency with an error margin of 17.2 MHz.Moreover,the fritting contact technique does not significantly affect qubit coherence time or the integrity of the superconducting film,confirming its non-destructive nature.This innovative approach provides a dependable foundation for frequency tuning and addressing frequency collision issues,thus supporting the advancement and practical deployment of superconducting quantum computing.

In-situ deposited anti-aging TiN capping layer for Nb superconducting quantum circuits

The performance of Nb superconducting quantum devices is predominantly limited by dielectric loss at the metal–air interface,where Nb2O5 is considered the main loss source.Here,we suppress the formation of native oxides by in-situ deposition of a TiN capping layer on the Nb film.With TiN capping layers,no Nb2O5 forms on the surface of the Nb film.The quality factor Qi of the Nb resonator increases from 5.6×10^(5) to 7.9×10^(5) at low input power and from 6.8×10^(6) to 1.1×10^(7)at high input power.Furthermore,the TiN capping layer also shows good aging resistance in Nb resonator devices,with no significant performance fluctuations after one month of aging.These findings highlight the effectiveness of TiN capping layers in enhancing the performance and longevity of Nb superconducting quantum devices.

Correction of microwave pulse reflection by digital filters in superconducting quantum circuits

Reducing the control error is vital for high-fidelity digital and analog quantum operations.In superconducting circuits,one disagreeable error arises from the reflection of microwave signals due to impedance mismatch in the control chain.Here,we demonstrate a reflection cancelation method when considering that there are two reflection nodes on the control line.We propose to generate the pre-distortion pulse by passing the envelopes of the microwave signal through digital filters,which enables real-time reflection correction when integrated into the field-programmable gate array(FPGA).We achieve a reduction of single-qubit gate infidelity from 0.67%to 0.11%after eliminating microwave reflection.Real-time correction of microwave reflection paves the way for precise control and manipulation of the qubit state and would ultimately enhance the performance of algorithms and simulations executed on quantum processors.

雷公藤内酯醇抑制TNF-α表达对小鼠溃疡性结肠炎的影响

目的了解雷公藤内酯醇(TL)对葡聚糖硫酸钠(DSS)致溃疡性结肠炎(UC)小鼠的疗效,探索其是否与抑制肿瘤坏死因子-α(TNF-α)过表达相关。方法复制DSS致UC小鼠动物模型,分为空白对照组、生理盐水组、丙二醇组、地塞米松组、美莎拉嗪组,以及TL 1、2、3组。分别予以3种剂量的TL,以及美沙拉嗪、地塞米松治疗,观察小鼠疾病活动指数、结肠组织学评分、结肠病理学评分,检测TNF-α在血清和局部病变组织中的表达变化。结果 TL组、地塞米松组、美莎拉嗪组小鼠结肠炎症状减轻,TNF-α表达下调。TL 2、3组及地塞米松组、美莎拉嗪组分别与生理盐水组、丙二醇组比较,差异有统计学意义(P<0.05)。结论 TL对UC有治疗作用,可能是通过抑制TNF-α过表达发挥作用,提示TL可能是一种有效的治疗UC的方法。

MiRNA profile in esophageal squamous cell carcinoma:Downregulation of miR-143 and miR-145

AIM:To investigate the expression profile of miRNA in esophageal squamous cell carcinoma(ESCC).METHODS:The expression profile of miRNA in ESCC tissues was analyzed by miRNA microarray.The expression levels of miR-143 and miR-145 in 86 ESCC patients were determined by real-time polymerase chain reaction(PCR) using TaqMan assay.The mobility effect was estimated by wound-healing using esophageal carcinoma cells transfected with miRNA expression plasmids.RESULTS:A set of miRNAs was found to be deregulated in the ESCC tissues,and the expression levels of miR-143 and-145 were significantly decreased in most of the ESCC tissues examined.Both miR-143 and miR-145 expression correlated with tumor invasion depth.The transfection of human esophageal carcinoma cells with miR-143 and miR-145 expression plasmids resulted in a greater inhibition of cell mobility,however,the protein level of the previously reported target of miR-145,FSCN1,did not show any significant downregulation.CONCLUSION:These findings suggest that the deregulation of miRNAs plays an important role in the progression of ESCC.Both miR-143 and miR-145 might act as anti-oncomirs common to ESCC.

Effect of tool plunge depth on the microstructure and fracture behavior of refill friction stir spot welded AZ91 magnesium alloy joints

We used refill friction stir spot welding(RFSSW)to join 2-mm-thick AZ91D-H24 magnesium alloy sheets,and we investigated in detail the effect of tool plunge depth on the microstructure and fracture behavior of the joints.A sound joint surface can be obtained using plunge depths of 2.0 and 2.5 mm.Plunge depth was found to significantly affect the height of the hook,with greater plunge depths corresponding to more severe upward bending of the hook,which compromised the tensile-shear properties of the joints.The hardness reached a minimum at the thermo-mechanically affected zone due to the precipitation phases of this zone as it dissolved into theα-matrix during the welding process.The fracture modes of RFSSW joints can be divided into three types:shear fracture,plug fracture,and shear–plug fracture.Of these,the joint with a shear–plug fracture exhibited the best tensile-shear load of 6400 N.

Experiment on diffuse reflection laser ranging to space debris and data analysis

Space debris poses a serious threat to human space activities and needs to be measured and cataloged. As a new technology for space target surveillance, the measurement accuracy of diffuse reflection laser ranging （DRLR） is much higher than that of microwave radar and optoelectronic measurement. Based on the laser ranging data of space debris from the DRLR system at Shanghai Astronomical Observatory acquired in March-April, 2013, the characteristics and precision of the laser ranging data are analyzed and their applications in orbit determination of space debris are discussed, which is implemented for the first time in China. The experiment indicates that the precision of laser ranging data can reach 39 cm-228 cm. When the data are sufficient enough （four arcs measured over three days）, the orbital accuracy of space debris can be up to 50 m.

Spontaneous infiltration and wetting behaviors of a Zr-based alloy melt on a porous SiC substrate

The spontaaleous infiltration aald wetting behaviors of a Zr-based alloy melt on porous a SiC ceramic plate were studied using tile sessile drop metilod by continuous heating and holding for 1800 s at different temperatures in a high-vacuum furnace. The results showed that tile Zr-based alloy melt could pastly infiltrate tile porous SiC substrate without pressure due to tile effect of capillary pressure. Wettability and infiltration rates increased witil increasing temperature, and interracial reaction products （ZrC0.7 and TiC） were detected in tile Zr-based alloy/SiC ceramic system, likely because of tile reaction of tile active elements Zr and Ti witil elemental C. Furtilelinore, tile redundant ele- ment Si diffused into tile alloy melt.

Neuroprotective effect of luteolin-7-O-β-D-glucuronide in a rat model offocal cerebral ischemia

OBJECTIVE To investigate the neuroprotective effect and possible mechanisms of lute.olin-7-O-β-D-glucuronide(LGU) against focalcerebral ischemic injury.METHODS The focal cerebral ischemic injury model was established by middle cerebral artery occlusion(MCAO).Male Sprague Dawley rats were randomly divided into sham group,model group(MCAO),LGU group(0.24,0.72 and2.16 mg·kg^(-1)) and positive control group(Edaravone at 5 mg·kg^(-1)).LGU was injected intravenously 30 min after MCAO.Neurological severity score,infarct volume and brain water content were detected 24 h after MCAO and the levels of Na+-K+ ATPase,Ca2 + ATPase,TNF-α and IL-1β were detected to explore the possible mechanisms.For the therapeutic time window test,LGU(0.72 mg·kg^(-1)) was injected intrave.nously 0.5,2,4,6,8,10 and 12 h respectively after MCAO.To evaluate motion behavior,LGU were injected intravenously 30 min after MCAO and once per day during detection period.The changes of motor coordination were detected by rotating rod method and grip strength analysis,and the changes of gaits were detected using DigiGait Imaging System.RESULTS LGU improved the neurological severity score,infarct volume ratio and brain water content.The therapeutic time window of LGU for cerebral infarction and brain edema was at least 6 h and for neurological dysfunction was 12 h.LGU also prolonged the latency on rotarod,increased the forelimb tension and improved 8 gait parameters,including stance duration,stride length,stance width,paw area,paw area variability,gait symmetry,ataxia coefficient and tau propulsion.Furthermore,LGU increased Na^+-K^+-ATPase and Ca^(2+)-ATPase levels in the cortex and hippocampus in the ischemic side,reduced the levels of TNF-α and IL-1β in the serum.CONCLUSION LGU has a significant neuroprotective effect against cerebral ischemic injury via improving energy metabolism and reducing inflammation.

Protective effect of luteolin-7-O-β-D-glucuronide against oxygenglucose deprivation-induced H9C2 cardiomyocytes injury

OBJECTIVE To investigate the protective effect and mechanisms of luteolin-7-O-β-dglucuronide(LGU) on oxygen glucose deprivation(OGD)-induced H9C2 cardiomyocytes injury.METH.ODS The protective effect of LGU on OGD-induced H9C2 cardiomyocytes death were investigated by MTT assay.The microfilament change of H9C2 cardiomyocytes was detected by phalloidin staining and the lactate dehydrogenase(LDH) leakage rate was also detected by LDH kit.In order to explore the possible mechanisms of LGU,ATP content,intracellular Ca^(2+) fluorescent intensity and concentra.tion,mitochondrial membrane potential(MMP)and the expressions of apoptosis-related proteins were detected by ATP kit,CLSM(Fluo-3/AM probe),Ca^(2+) kit,CLSM(JC-1 probe) and western blotting meth.od,respectively.RESULTS The inhibition of H9C2 cardiomyocyte survival rate inducedby OGD was improvedby pretreated with LGU in a concentrationdependent manner.The microfilaments injury as well as the increase of LDH leakage rate were also improvedby pretreated with LGU.The ATP content was significantly decreased,intracellular Ca^(2+) fluorescent intensity and concentration were significantly increased and the MMP was significantly decreased 4 hafter OGD.LGU significantly reversed the de.crease of intracellular ATP content,the increase of Ca^(2+) fluorescent intensity and concentration and the decrease of MMP.The release of cytochrome C,the expressionsof caspase-9 and caspase-3 in H9C2 cardiomyocytes were increased 16 h after OGD.LGUsignificantly inhibited the changes of these apop.tosis-related proteins.CONCLUSION LGU has a significant protective effect against OGD-induced H9C2 cardiomyocytes injury through inhibiting calcium overload,increasing ATP content,improving mi.tochondrial function and inhibiting apoptosis.

Dynamic indentation response of porous SiC/Ti-based metallic glass composite

Porous SiC/Ti-based metallic glass composite (Ti-BMGC), a new kind of composite, has significant application prospectin the field of light armor. To evaluate the dynamic mechanical response of the composite, dynamic Vickers hardness andindentation-induced deformation behavior were investigated by comparison with that under static indentation. The dynamic hardnesswas measured by a modified split Hopkinson pressure bar (SHPB). The dynamic hardness is obviously greater than the statichardness. The brittleness parameter under dynamic indentation is also greater than that under static indentation. Although thedynamic indentation induced more severe deformation behavior than the static indentation, the deformation and fracturecharacteristics in the two loading cases are nearly the same, both exhibiting extensive cracks in the SiC phase and severe plasticdeformation in the metallic glass phase.

An integral method for calculation of capillary pressure based on centrifuge data of tight sandstone

The traditional Hassler-Brunner(HB)interpretation method of centrifuge capillary pressure is widely used in materials,soil,biotechnology,and especially in the petroleum industry.However,the assumptions of the traditional method cannot be simultaneously satisfied,the traditional method has been known to lead significant errors in some cases.In this paper,a new double integral method is proposed to evaluate the centrifuge capillary pressure of long tight sandstone samples.Both the changes of capillary length and interface of wetting phase and non-wetting phase fluids are considered by the new integral method,thus the average pressure and saturation derived from the proposed double integral method is more sufficient in theoretic foundation and clearer on physical meaning.By comparing with the measured capillary pressure of long tight sandstone core samples from porous plate,the capillary pressure calculated from traditional HB method is obviously smaller than the measured value,and the discrepancy increases with the decreasing core porosity.However,the average capillary pressure obtained by the proposed double integral method is remarkably consistent with the measured value.The findings of this study can help for better understanding of distribution of wetting phase fluid and average centrifuge capillary pressure in the core during centrifugal process.

High-quality CdS quantum dots sensitized ZnO nanotube array films for superior photoelectrochemical performance

The surface characteristics of ZnO were synthetically optimized by a self-designed simultaneous etching and W-doping hydrothermal method utilizing as-prepared ZnO nanorod(NR)array films as the template.Benefiting from the etching and regrowth process and the different structural stabilities of the various faces of ZnO NRs,the uniquely etched and W-doped ZnO(EWZ)nanotube(NT)array films with larger surface area,more active sites and better energy band structure were used to improve the photoelectrochemical(PEC)performance and the loading quality of CdS quantum dots(QDs).On the basis of their better surface characteristics,the CdS QDs were uniformly loaded on EWZ NT array film with a good coverage ratio and interface connection;this effectively improved the light-harvesting ability,charge transportation and separation as well as charge injection efficiency during the PEC reaction.Therefore,all the CdS QD-sensitized EWZ NT array films exhibited significantly enhanced PEC performance.The CdS/EWZ-7 composite films exhibited the optimal photocurrent density with a value of 12 mA·cm^(-2),2.5 times higher than that of conventional CdS/ZnO-7 composite films under the same sensitization times with CdS QDs.The corresponding etching and optimizing mechanisms were also discussed.

Dynamics of a Reaction-diffusion-ODE System in a Heterogeneous Media

The existence and stability of stationary solutions for a reaction-diffusion-ODE system are investigated in this paper.We first show that there exist both continuous and discontinuous stationary solutions.Then a good understanding of the stability of discontinuous stationary solutions is gained under an appropriate condition.In addition,we demonstrate the influences of the diffusion coefficient on stationary solutions.The results we obtained are based on the super-/sub-solution method and the generalized mountain pass theorem.Finally,some numerical simulations are given to illustrate the theoretical results.

Tumor microenvironment-responsive arsenic-loaded layered double hydroxides film with synergistic anticancer and bactericidal activity

Malignant obstruction makes gallbladder cancer have a high mortality rate.Nickel-titanium alloy(nitinol)stents are commonly used as a local intervention to maximize patient survival time,but the stents lack antitumor and antibacterial capacity and are vulnerable to secondary obstruction.Arsenic-based drugs show good therapeutic promise against gallbladder cancer.To meet clinical needs.the layered double hydroxides(LDHs)film is constructed on the nitinol,whose arsenite loading amounts rose by 60%after simple heat treatment compared with the conventional anion-exchange strategy.In addition,calcination promotes the dissolution of nickel ions from the LDHs lattice,resulting in a powerful synergistic killing effect on tumor cells together with the released arsenic.More importantly,the calcined arsenic-loaded LDHs are sensitive to the acidic microenvironment of tumor tissues,which presents a much lower arsenic and nickel release amount in the normal tissues,guaranteeing its biosafety.Meanwhile,the vertically sharp LDHs nanosheets can synergize with arsenic to achieve effective physical cleavage and chemical killing of adherent and planktonic bacteria.In short,we attempt to use arsenic drugs for local interventions and reasonably avoid their toxic side effects,which provides a new design idea for nitinol stents applied in the treatment of gallbladder cancer.

Mechanical properties and deformation behavior of Zr-based bulk metallic glass composites reinforced with tungsten fibers or tungsten powders

The tungsten fibers or powders reinforced Zr_(52)Cu_(32)Ni_(6)Al_(10),(Zr_(52)Cu_(32)Ni_(6)Al_(10))_(98)Nb_(2),and(Zr_(52)Cu_(32)Ni_(6)Al_(10))_(98)Be_(2)bulk metallic glass composites(BMGCs)were fabricated using the infiltration casting method.In this study,the wettability between the amorphous alloy melts and tungsten substrates was investigated using the sessile drop method,revealing excellent wettability at 1,010℃.Consequently,an infiltration temperature of 1,010°C was chosen for composite material fabrication.Structural characterization and mechanical property test of both composites were conducted through scanning electron microscopy(SEM),and X-ray diffraction(XRD),and universal mechanical testing.Both tungsten fiber or tungsten powder reinforced Zr_(52)Cu_(32)Ni_(6)Al_(10)and(Zr_(52)Cu_(32)Ni_(6)Al_(10))_(98)Be_(2)composites exhibit the formation of W-Zr phase.In contrast,the tungsten fiber or tungsten powder reinforced(Zr_(52)Cu_(32)Ni_(6)Al_(10))_(98)Nb_(2)composites does not show the formation of W-Zr phase.X-ray diffraction patterns confirm the presence of W reinforcement phases in both composites.The successful fabrication of both composites is evidenced by their remarkable mechanical properties under room temperature compression.The yield strength of all the three tungsten fiber-reinforced composite sample exceeds 2,400 MPa,with the plastic strain exceeding 3.9%,while the yield strength of all the three tungsten powder-reinforced composite sample surpasses 2,700 MPa,with the plastic strain exceeding 30%.Fracture analysis reveals longitudinal splitting in the tungsten fiber-reinforced composites,contrasting with brittle fracture in the tungsten powder-reinforced composites.The denser the shear bands on the amorphous matrix of the two types of composite materials,the better their mechanical properties.

Growth differentiation factor-15 combined with N-terminal prohormone of brain natriuretic peptide increase 1-year prognosis prediction value for patients with acute heart failure: a prospective cohort study

Background:Clinical assessment and treatment guidance for heart failure depends on a variety of biomarkers.The objective of this study was to investigate the prognostic predictive value of growth differentiation factor-15(GDF-15)and N-terminal prohormone of brain natriuretic peptide(NT-proBNP)in assessing hospitalized patients with acute heart failure(AHF).Methods:In total,260 patients who were admitted for AHF in the First Affiliated Hospital of Nanjing Medical University were enrolled from April 2012 to May 2016.Medical history and blood samples were collected within 24 h after the admission.The primary endpoint was the all-cause mortality within 1 year.The patients were divided into survival group and death group based on the endpoint.With established mortality risk factors and serum GDF-15 level,receiver-operator characteristic(ROC)analyses were performed.Cox regression analyses were used to further analyze the combination values of NT-proBNP and GDF-15.Results:Baseline GDF-15 and NT-proBNP were significantly higher amongst deceased than those in survivors(P<0.001).In ROC analyses,area under curve(AUC)for GDF-15 to predict 1-year mortality was 0.707(95%confidence interval[CI]:0.648–0.762,P<0.001),and for NT-proBNP was 0.682(95%CI:0.622–0.738,P<0.001).No statistically significant difference was found between the two markers(P=0.650).Based on the optimal cut-offs(GDF-15:4526.0 ng/L;NT-proBNP:1978.0 ng/L),the combination of GDF-15 and NT-proBNP increased AUC for 1-year mortality prediction(AUC=0.743,95%CI:0.685–0.795,P<0.001).Conclusions:GDF-15,as a prognostic marker in patients with AHF,is not inferior to NT-proBNP.Combining the two markers could provide an early recognition of high-risk patients and improve the prediction values of AHF long-term prognosis.Clinical trial registration:ChiCTR-ONC-12001944,http://www.chictr.org.cn.

Prognostic Impact of Fasting Plasma Glucose on Mortality and Re-Hospitalization in Patients with Acute Heart Failure

Background： The impact of fasting plasma glucose （FPG） on survival outcomes in patients with acute heart failure （HF） is unclear, and the relationship between intensity of glycemic control of FPG in diabetes mellitus （DM） patients and HF prognosis remains uncertain. This retrospective study aimed to evaluate the prognostic impact of FPG in patients with acute HF. Methods： A total of 624 patients hospitalized with acute HF from October 2000 to April 2014 were enrolled in this study. All patients were stratified by three groups according to their admission FPG levels （i.e., DM, impaired fasting glucose [IFG], and non-DM）. All-cause and cardiovascular mortality was the primary end point, and HF re-hospitalization was the secondary end point during follow-up period. Results： A total of 587 patients were included in final analysis. The all-cause mortality rates of patients with DM, IFG, and non-DM were 55.5%, 40.3%, and 39.2%, with significant difference （P = 0.001 ）. Moreover, compared with those with IFG （34.3%） and non-DM （32.6%）, patients with DM had significantly higher rate of cardiovascular mortality （45.1%）. Multiple Cox regression analysis showed that DM as well as IFG was related to all-cause mortality （DM： hazard ratio [HR] = 1.936, P 〈 0.001; IFG： FIR = 1.672, P = 0.019） and cardiovascular mortality （DM： HR = 1.739, P 〈 0.001; IFG： HR = 1.817, P = 0.013）. However, they were both unrelated to HF re-hospitalization. DM patients with strictly controlled blood glucose （FPG 〈3.9 mmol/L） had higher all-cause mortality than patients with non-DM, IFG, and DM patients with moderately controlled glucose （3.9 mmol/L_〈 FPG 〈7.0 mmol/L）. Likewise, both the primary end point and secondary end point were found to be worse in DM patients with poorly controlled blood glucose （FPG ≥7.0 mmol/L）. Conclusions： IFG and DM were associated with higher all-cause mortality and cardiovascular mortality in patients with acute HF. The association between mortality and admission FPG in DM patients with acute HF appeared U-shaped.