Velocity analysis of supersonic jet flow in double-cone ignition scheme

In the double-cone ignition schemes(DCIS), the deuterium–tritium target shell is ablated and compressed by a highpower nanosecond laser in Au-cones to generate plasmas. Under the actions of spherically symmetric compression and acceleration along the Au cone, they will be ejected out of the cone mouth and collide with each other. The plasmas experience conversion from kinetic energy to internal energy at the vertex of the geometric center of two Au cones that are symmetric to each other, because of which high-density fusion plasmas are preheated. This key physical process has undergone experimental verification on the Shenguang-II upgraded facility in China. Apparently, the improvement and optimization of the velocity of plasmas in hypersonic jet flow at the cone mouth are crucial for the success of the DCIS. In the DCIR7 experiment of the Shenguang-II upgraded facility, a velocity yield of approximately 130–260 km/s was achieved for the plasmas at the cone mouth, with a result of nearly 300 km/s based on numerical simulation. In this paper, theoretical analysis is performed as regards the process, in which target shells are ablated and compressed by laser to generate highvelocity plasmas ejected through jet flow. Based on this analysis, the formula for the velocity of plasmas in supersonic jet flow at the cone mouth is proposed. This study also provides measures that are more effective for improving the kinetic energy of plasmas and optimizing energy conversion efficiency, which can serve as theoretical references for the adjustment and optimization of processes in subsequent experiments.

Nomogram based on clinical characteristics for predicting overall survival in gastric cancer patients with preoperative anemia

BACKGROUND Preoperative anemia is associated with increased postoperative morbidity and mortality and increased perioperative transfusion risk.For surgical patients,this affects physical and cognitive ability and quality of life,but it is an important and modifiable risk factor.AIM To determine the effect of preoperative anemia on the prognosis of gastric cancer(GC)patients and generate a prognostic nomogram to predict the postoperative overall survival(OS)of GC patients with preoperative anemia.METHODS Clinicopathological and follow-up data of GC patients treated at Zhejiang Provincial People's Hospital(China)from 2010 to 2015 were collected.Independent prognostic factors were screened by univariate and multivariate Cox regression analyses.Then,these factors were used to construct a nomogram to predict 1-,3-,and 5-year postoperative OS in preoperative anemic GC patients.The nomogram was assessed by calibration curves,receiver operating characteristic(ROC)curves,and decision curve analysis(DCA).RESULTS Nine hundred and sixty GC patients were divided into two groups(preoper atively anemic and nonanemic),and postoperative survival analysis was performed on both groups,yielding a shorter postoperative survival for preoperatively anemic patients than for nonanemic patients.A total of 347 GC patients with preoperative anemia were included.Age,preoperative alpha-fetoprotein level,monocyte count,lymphocyte count,clinicopathological stage,liver metastasis,and GC type were identified as independent prognostic factors for OS.The area under the ROC curve(AUC)of the nomogram for predicting 1-,3-,and 5-year OS was 0.831,0.845,and 0.840,respectively,for the training cohort,and the corresponding AUC values in the validation cohort were 0.827,0.829,and 0.812,respectively.Calibration curves and DCA indicated good performance of the nomogram.CONCLUSION In all,we have successfully produced and verified a useful nomogram for predicting OS in GC patients with preoperative anemia.This nomogram based on a variety of clinicopathological indices can provide an effective prognostic assessment and help clinicians choose an appropriate treatment strategy for GC patients with preoperative anemia.

Ultrafast two-dimensional x-ray imager with temporal fiducial pulses for laser-produced plasmas

It is challenging to make an ultrafast diagnosis of the temporal evolution of small and short-lived plasma in two dimensions. To overcome this difficulty, we have developed a well-timed diagnostic utilizing an x-ray streak camera equipped with a row of multi-pinhole arrays. By processing multiple sets of one-dimensional streaked image data acquired from various pinholes, we are capable of reconstructing high-resolution two-dimensional images with a temporal resolution of 38 ps and a spatial resolution of 18 μm. The temporal fiducial pulses accessed from external sources can advance the precise timing and accurately determine the arrival time of the laser. Moreover, it can correct the nonlinear sweeping speed of the streak camera. The effectiveness of this diagnostic has been successfully verified at the Shenguang-II laser facility,providing an indispensable tool for observing complex physical phenomena, such as the implosion process of laser-fusion experiments.

PandA(Box)flies on Bluesky:maintainable and user-friendly fly scans with Mamba at HEPS

Purpose Fly scans are indispensable in many experiments at the High Energy Photon Source(HEPS).PandABox,the main platform to implement fly scans at HEPS,needs to be integrated into Mamba,the experiment control system developed at HEPS based on Bluesky.Methods In less than 600 lines of easily customisable and extensible backend code,provided are full control of PandABox’s TCP server in native ophyd,automated configuration(also including wiring)of“PandA blocks”for constant-speed mapping experiments of various dimensions,as well as generation of scans deliberately fragmented to deal with hardware limits in numbers of exposure frames or sequencer table entries.Results The upper-level control system for PandABox has been ported to Bluesky,enabling the combination of both components’flexibility in fly-scan applications.Based on this backend,a user-friendly Mamba frontend is developed for X-ray fluorescence(XRF)mapping experiments,which provides fully online visual feedback.