Studies of an event-building algorithm of the readout system for the twin TPCs in HFRS

The High-energy Fragment Separator(HFRS),which is currently under construction,is a leading international radioactive beam device.Multiple sets of position-sensitive twin time projection chamber(TPC)detectors are distributed on HFRS for particle identification and beam monitoring.The twin TPCs'readout electronics system operates in a trigger-less mode due to its high counting rate,leading to a challenge of handling large amounts of data.To address this problem,we introduced an event-building algorithm.This algorithm employs a hierarchical processing strategy to compress data during transmission and aggregation.In addition,it reconstructs twin TPCs'events online and stores only the reconstructed particle information,which significantly reduces the burden on data transmission and storage resources.Simulation studies demonstrated that the algorithm accurately matches twin TPCs'events and reduces more than 98%of the data volume at a counting rate of 500 kHz/channel.

The impact of both platinum-based chemotherapy and EGFR-TKIs on overall survival of patients with advanced non-small cell lung cancer

Both platinum-based doublet chemotherapy(PBC) and epidermal growth factor receptor tyrosine kinase inhibitors(EGFR-TKIs) prolong the survival of patients with advanced non-small cell lung cancer(NSCLC). In early studies, most patients underwent PBC as first-line treatment, but not all patients could afford EGFR-TKIs as second-line treatment. To understand the impact of PBC and EGFR-TKIs on NSCLC prognosis, we evaluated the association between the receipt of both regimens and overall survival(OS). Using MEDLINE and EMBASE, we identified prospective, randomized, controlled phase III clinical trials in advanced NSCLC that met the inclusion criteria: in general population with advanced NSCLC, the percentage of patients treated with both PBC and EGFR-TKIs was available in the trial and OS was reported. After collecting data from the selected trials, we correlated the percentage of patients treated with both PBC and EGFR-TKIs with the reported OS, using a weighted analysis. Fifteen phase III clinical trials—involving 11,456 adult patients in 32 arms—were included in the analysis, including 6 trials in Asian populations and 9 in non-Asian(predominantly Caucasian) populations. The OS was positively correlated with the percentage of patients treated with both PBC and EGFR-TKIs(r = 0.797, P < 0.001). The correlation was obvious in the trials in Asian populations(r = 0.936, P < 0.001) but was not statistically significant in the trials in predominantly Caucasian populations(r = 0.116, P = 0.588). These results suggest that treatment with PBC and EGFR-TKIs may provide a survival benefit to patients with advanced NSCLC, highlighting the importance of having both modalities available for therapy.

SPARC expression and prognostic value in non-small cell lung cancer

Secreted protein,acidic and rich in cysteine(SPARC) is expressed in numerous types of tumors and is suggested to have prognostic value.Moreover,because of its strong affinity for albumin,and hence albumin-bound drugs,SPARC has increasingly become a focus for research.In this study,we aimed to determine SPARC expression in patients with non-small cell lung cancer(NSCLC) and investigate the association of SPARC with disease prognosis.Tissue microarrays were constructed with specimens from 105 patients with NSCLC treated at Sun Yat-sen University Cancer Center,and immunohistochemical analysis was performed on these tissue microarrays to assess SPARC expression.Our results showed that SPARC expression status did not significantly relate with age,gender,and tumor stage.However,SPARC was expressed more frequently in squamous cell carcinoma than in adenocarcinoma(75% vs.43.5%,P = 0.004).Patients with smoking history had higher SPARC expression than non-smokers(68.2% vs.33.3%,P = 0.002).In both univariate and multivariate analyses,SPARC was a prognostic factor of overall survival(HR = 0.32;95% CI:0.16-0.65) but not disease-free survival.Our study indicates that SPARC expression is higher in squamous cell carcinoma than in adenocarcinoma in NSCLC.Most notably,SPARC can be used as a prognostic factor for NSCLC.

Expression of RRM1 and its association with resistancy to gemcitabine-based chemotherapy in advanced nasopharyngeal carcinoma

Gemcitabine has high activity against nasopharyngeal carcinoma(NPC).The level of ribonucleotide reductase subunit M1(RRM1) expression is closely related to the efficacy of gemcitabine on non-small cell lung cancer and pancreatic cancer.However,the expression of RRM1 and its association with sensitivity to gemcitabine-based chemotherapy in advanced NPC is not known.In this study,we retrospectively collected 48 formalin-fixed,paraffin-embedded NPC tissues to evaluate the expression of RRM1 using immunohistochemistry.All patients were diagnosed and treated with gemcitabine-based chemotherapy at Sun Yat-sen University Cancer Center.RRM1 expression was positive in 17(35%) patients.RRM1 expression was not associated with sex,age,performance status,WHO histological type,number of distant metastases,previous treatment,or cycles of gemcitabine-based chemotherapy(P> 0.05).The progression-free survival of the RRM1-positive group was shorter than that of the RRM1-negative group(5 months vs.7 months,P = 0.036),and the response rate of the RRM1-positive group was somewhat lower than that of the RRM1-negative group(51.6% vs.35.3%,P = 0.278).There was no significant difference in median survival between the RRM1-positive and RRM1-negative groups(22 months vs.19 months,P = 0.540).Our results show that RRM1-negative expression is related with longer progression-free survival in advanced NPC patients treated with gemcitabine-based regimens.

Microstructure and mechanical properties of heat affected zone in multi-pass GMA welded Al-Zn-Mg-Cu alloy

Microstructure and mechanical properties of the heat affected zone(HAZ)in multi-pass gas metal arc(GMA)welded Al Zn Mg Cu alloy plates were investigated,based upon which the mechanical anisotropy and fracture mechanism were analyzed.The microstructure and composition were analyzed by scanning electron microscope(SEM)and energy dispersive spectroscope(EDS).X-ray diffractometer(XRD),transmission electron microscope(TEM)and selective area electron diffraction(SAED)were used to analyze the phase composition.The distribution of microhardness was identified as gradual transition and tensile strength had a tendency to decrease first and then increase.The distribution of nano-sizedη(MgZn2)particles in theα(Al)matrix and Al2MgCu phase determined the tensile performances along the thickness direction and led to the formation of ductile/brittle composite fracture in the HAZ.The continuous distribution of Al2MgCu phase in the strip intergranular precipitates gave birth to premature cracks and the brittle fracture region.The precipitated particles coarsening also led to the deterioration of mechanical properties.

Prediction of proton-induced SEE error rates for the VATA160 ASIC

We predict proton single event effect(SEE)error rates for the VATA160 ASIC chip on the Dark Matter Particle Explorer(DAMPE) to evaluate its radiation tolerance.Lacking proton test facilities,we built a Monte Carlo simulation tool named PRESTAGE to calculate the proton SEE cross-sections.PRESTAGE is based on the particle transport toolkit Geant4.It adopts a location-dependent strategy to derive the SEE sensitivity of the device from heavy-ion test data,which have been measured at the HI-13 tandem accelerator of the China Institute of Atomic Energy and the heavy-ion research facility in Lanzhou.The AP-8,SOLPRO,and August 1972 worst-case models are used to predict the average and peak proton fluxes on the DAMPE orbit.Calculation results show that the averaged proton SEE error rate for the VATA160 chip is approximately 2.17×10^(-5)/device/day.Worst-case error rates for the Van Allen belts and solar energetic particle events are 1-3 orders of magnitude higher than the averaged error rate.

Design of fast adaptive readout system for wire scanners

A new wide-range fast readout system capable of adaptive identification is designed for wire scanners,which are used to measure beam profiles and emittance.This system is capable of handling varying current signals with Gaussian distributions and current pulses up to 1000 counts/s, as well as an input current range of 1 n A–1 m A. When tested, the resolution was found to exceed 3.68% for full scale, the nonlinearity was found to be less than 0.11%, and the measurement sensibility was found to be less than 5 p A. We believe that the system will play a crucial role in improving the measurement accuracy of beam diagnosis and the efficiency of accelerator operation,as well as decreasing the time required for beam tuning.This system was applied to the beam diagnosis of an injector II prototype for an accelerator-driven subcritical system and produced excellent measurement results. A description of the adaptive fast readout system for wire scanners is presented in this paper.

A phase I study of toripalimab, an anti-PD-1 antibody, in patients with refractory malignant solid tumors

Background:Several programmed cell death ligand 1(PD-L1)/programmed cell death protein 1(PD-1)antibodies have been approved for cancer treatmentworldwide.Their pharmacokinetic and pharmacodynamic characteristics have been reported mainly in western countries,but related data in Chinese patients are limited.This study was conducted to investigate the safety,efficacy,pharmacokinetics,and pharmacodynamics of an anti-PD-1 antibody,toripalimab,in Chinese patients.Methods:A single-center phase I study was conducted in Sun Yat-sen University Cancer Center.Eligible patients were adults with histologically confirmed,treatment-refractory,advanced,solitary malignant tumors.Toripalimab was intravenously infused every 2 weeks in dose-escalating cohorts at 0.3mg/kg,1 mg/kg,3 mg/kg,10 mg/kg,and 240 mg.The study followed standard 3+3 design.Results:Between 15th March 2016 and 27th September 2016,25 patients were enrolled,of whom 3(12.0%),7(28.0%),6(24.0%),6(24.0%),3(12.0%)received 0.3 mg/kg,1 mg/kg,3 mg/kg,10 mg/kg,and 240 mg toripalimab,respectively.After a median follow-up time of 5.0 months(range:1.5-19.8 months),we observed that the commonest treatment-related adverse events(TRAEs)were fatigue(64.0%)and rash(24.0%).No grade 3 or higher TRAEs were observed.No dose-limiting toxicity,treatment-related serious adverse events(SAEs),or treatment-related death occurred.Objective response ratewas 12.5%.The half-life of toripalimabwas 150-222 h after a single dose infusion.Most patients,including those from the 0.3 mg/kg group,maintained complete PD-1 receptor occupancy(>80%)on activated T cells since receiving the first dose of toripalimab.Conclusions:Toripalimab is a promising anti-PD-1 antibody,which was well tolerated and demonstrated anti-tumor activity in treatment-refractory advanced solitary malignant tumors.Further exploration in various tumors and combination therapies is warranted.

Effect of Sleeve Plunge Depth on Interface/Mechanical Characteristics in Refill Friction Stir Spot Welded Joint

Refill friction stir spot welding was employed to produce 6061-T6 aluminum alloy joints with different sleeve plunge depths.The interface characteristics of joint-line remnant and hook are investigated by optical and scanning electron microscopy.The joint-line remnant consists of primary bonding region and secondary bonding region,and two types of hook can be identified as downward hook and upward hook.Tensile shear results demonstrate that joint-line remnant and hook make interaction effects on tensile shear properties.The optimal joint is achieved when sleeve plunge depth was 2.0 mm with the corresponding failure load of 8673.4 N.Three different types of fracture mode are exhibited in joints produced at different sleeve plunge depths,which are closely related with the morphology of interface characteristics.