An observation control system for radio telescopes based on Python and C++languages

An observation control system is the foundation to support automatic observations by any radio telescope.Traditional observation control systems are usually coded using a compiled language,which is of higher efficiency compared with interpreted languages.Indeed,observation control systems are usually programmed using the C or C++languages.However,the high execution efficiency of C/C++is at the cost of a long development cycle,which is not only time consuming but also requires considerable skills for the developers.The development of computer hardware performance,as well as the optimization of the just-in-time compiler for new interpreted languages such as Python,provides a good balance between execution and development efficiency.In this paper,we introduce the observation control system developed for the Kunming 40-meter radio telescope run by Yunnan Observatories,Chinese Academy of Sciences.The system is developed mainly with the Python language,and we have optimized computationally intensive components with C++.We demonstrate that it is possible to achieve the required functionality and control precision with such a Python-C++programming paradigm.The performance of the control system is also assessed in this paper,demonstrating that satisfactory pointing accuracy and user experience can be attained.

Enhancing interfacial Li+transport and dielectric properties in poly(ethylene oxide)-based all-solid electrolytes via inactive g-C_(3)N_(4)nanosheets filler incorporation

The advancement of all-solid-state Li metal batteries(ASSLMBs)faces a major challenge in the growth of lithium dendrites on the anode-electrolyte interface.In this study,we propose a dual-filler approach using poly(ethylene oxide)(PEO)-based solid polymer electrolytes(SPEs)that combine Li_(1.4)Al_(0.4)Ti_(1.6)(PO_(4))_(3)(LATP)ion-conductive particles with graphitic carbon nitride(g-C_(3)N_(4))nanosheets.Analysis through sec-ond harmonic resonance enhanced electrostatic force microscopy and critical current density(CCD)tests reveal that the g-C_(3)N_(4)additives form nano-capacitors at the SPE-lithium interface,effectively reducing sudden changes in current densities.The distribution of relaxation time constant(DRT)measurements confirms that the g-C_(3)N_(4)filler suppresses uncontrolled Li dendrite growth,effectively mitigating battery aging caused by anode interfacial degradation.Furthermore,X-ray photoelectron spectroscopy(XPS)anal-ysis indicates that the nitrogen-containing organic groups in g-C_(3)N_(4)are reduced to form a stable interfa-cial layer with lithium metal.As a result of these enhancements,the electrolyte demonstrates remarkable interfacial stability in Li/Li symmetrical cells at 0.65 mA/cm2 and delivers promising performance in assembled Li-LiFePO4 batteries,achieving a reversible capacity of 121.6 mAh/g at 1 C after 200 cycles.These findings highlight the potential of dual-filler PEO-based SPEs for promoting interfacial lithium-ion transport in all-solid-state Li metal batteries.

Aristolochic acids exposure was not the main cause of liver tumorigenesis in adulthood

Aristolochic acids(AAs) have long been considered as a potent carcinogen due to its nephrotoxicity. Aristolochic acid I(AAI) reacts with DNA to form covalent aristolactam(AL)-DNA adducts,leading to subsequent A to T transversion mutation, commonly referred as AA mutational signature. Previous research inferred that AAs were widely implicated in liver cancer throughout Asia. In this study, we explored whether AAs exposure was the main cause of liver cancer in the context of HBV infection in China's Mainland. Totally 1256 liver cancer samples were randomly retrieved from 3 medical centers and a refined bioanalytical method was used to detect AAI-DNA adducts. 5.10% of these samples could be identified as AAI positive exposure. Whole genome sequencing suggested 8.41% of 107 liver cancer patients exhibited the dominant AA mutational signature, indicating a relatively low overall AAI exposure rate. In animal models, long-term administration of AAI barely increased liver tumorigenesis in adult mice, opposite from its tumor-inducing role when subjected to infant mice. Furthermore, AAI induced dose-dependent accumulation of AA-DNA adduct in target organs in adult mice, with the most detected in kidney instead of liver. Taken together, our data indicate that AA exposure was not the major threat of liver cancer in adulthood.

Multi-objective interval prediction of wind power based on conditional copula function

Interval prediction of wind power,which features the upper and lower limits of wind power at a given confidence level,plays a significant role in accurate prediction and stability of the power grid integrated with wind power.However,the conventional methods of interval prediction are commonly based on a hypothetic probability distribution function,which neglects the correlations among various variables,leading to the decrease of prediction accuracy.Therefore,we improve the multi-objective interval prediction based on the conditional copula function,through which we can fully utilize the correlations among variables to improve prediction accuracy without an assumed probability distribution function.We use the multi-objective optimization method of nondominated sorting genetic algorithm-II(NSGA-II)to obtain the optimal solution set.The particular best solution is weighted by the prediction interval average width(PIAW)and prediction interval coverage probability(PICP)to pick the optimized solution in practical examples.Finally,we apply the proposed method to three wind power plants in different cities in China as examples forvalidation and obtain higher prediction accuracy compared with other methods,i.e.,relevance vector machine(RVM),artificial neural network(ANN),and particle swarm optimization kernel extreme learning machine(PSO-KELM).These results demonstrate the superiority and practicability of this method in interval prediction of wind power.

Combination therapy of thiamine,vitamin C and hydrocortisone in treating patients with sepsis and septic shock:a meta-analysis and trial sequential analysis

Background:The objective of this study was to evaluate the clinical efficacy of thiamine and vitamin C with or without hydrocortisone coadministration on the treatment of sepsis and septic shock.Methods:MEDLINE,EMBASE and CENTRAL databases were searched for randomized controlled trials(RCTs)that made a comparative study between the combination therapy of vitamin C and thiamine with or without hydrocortisone and the administration of placebo in patients with sepsis or septic shock.Two reviewers independently performed study selection,data extraction and quality assessment.Both short-term mortality and change in the sequential organ failure assessment(SOFA)score from baseline(delta SOFA)were set as the primary outcomes.Secondary endpoints included intensive care unit(ICU)mortality,new onset of acute kidney injury,total adverse events,ICU and hospital length of stay,duration of vasopressor usage and ventilator-free days.Meanwhile,trial sequential analysis was conducted for primary outcomes.Results:Eight RCTs with 1428 patients were included in the current study.The results showed no significant reduction of short-term mortality in sepsis and septic shock patients who received combination therapy of vitamin C and thiamine with or without hydrocortisone compared to those with placebo{risk ratio(RR),1.02[95%confidence interval(CI),0.87 to 1.20],p=0.81,I2=0%;risk difference(RD),0[95%CI,−0.04 to 0.05]}.Nevertheless,the combination therapy was associated with significant reduction in SOFA score[mean difference(MD),−0.63,(95%CI,−0.96 to−0.29,p<0.001,I^(2)=0%]and vasopressors duration(MD,−22.11[95%CI,−30.46 to−13.77],p<0.001,I2=6%).Additionally,there were no statistical differences in the pooled estimate for other outcomes.Conclusions:In the current meta-analysis,the combination therapy of vitamin C and thiamine,with or without hydrocortisone had no impact on short-term mortality when compared with placebo,but was associated with significant reduction in SOFA score among patients with sepsis and septic shock.

Measuring clock jumps using pulsar timing

In this paper,we investigate the statistical signal-processing algorithm to measure the instant local clock jump from the timing data of multiple pulsars.Our algorithm is based on the framework of Bayesian statistics.In order to make the Bayesian algorithm applicable with limited computational resources,we dedicated our efforts to the analytic marginalization of irrelevant parameters.We found that the widely used parameter for pulsar timing systematics,the"Efac"parameter,can be analytically marginalized.This reduces the Gaussian likelihood to a function very similar to the Student’s t-distribution.Our iterative method to solve the maximum likelihood estimator is also explained in the paper.Using pulsar timing data from the Yunnan Kunming 40-m radio telescope,we demonstrate the application of the method,where 80-ns level precision for the clock jump can be achieved.Such a precision is comparable to that of current commercial time transferring service using satellites.We expect that the current method could help developing the autonomous pulsar time scale.