Measuring information transmission in Izhikevich neuron

Izhikevich neuron is a relatively new neuronal model, which has found extensive applications in modeling neuron due to its strong biological plausibility and computational effectiveness. In this work we use the information theoretic method to measure the ability of information transmission of this neuron model. We find that Izhikevich neuron shows low sensitivity to high frequency of random noise; and appropriate noise level can help information transmission through the neuron

Using Tianwen-1 Differential One-way Range Signals to Probe Corotating Interaction Regions: Case Studies

The study reports the first detection of corotating interaction regions (CIRs) in the solar wind by the differential one-way range (DOR) signals transmitted by Tianwen-1. Differential phase delay is calculated for the DOR signals. Variations of the total electron content (TEC) along the signal path between Tianwen-1 and the ground stations are then derived from changes in the differential phase delay. Large TEC variations are found for 2021 February 11, 18, and 19 even after the influence from the Earth’s ionosphere has been removed. In situ solar wind measurements and the corresponding simulation results further show that the TEC variations are caused by the CIRs that passed through the signal path on these days. The study demonstrates that CIR structures can be probed using deep-space spacecraft range signals. Such measurements can be used to constrain global solar wind forecast models

An elastic model of Phobos’ libration

Context. Study the rotation of a celestial body is an efficient way to infer its interior structure, and then may give information of its origin and evolution. In this study, based on the latest shape model of Phobos from Mars Express (MEX) mission, the polyhedron approximation approach was used to simulate the gravity field of Phobos. Then, the gravity information was combined with the newest geophysical parameters such as GM and k2 to construct the numerical model of Phobos’ rotation. And with an appropriate angles transformation, we got the librational series respect to Martian mean equator of date. Aims. The purpose of this paper is to develop a numerical model of Phobos’ rotational motion that includes the elastic properties of Phobos. The frequencies analysis of the librational angles calculated from the numerical integration results emphasize the relationship between geophysical properties and dynamics of Phobos. This work will also be useful for a future space mission dedicated to Phobos. Methods. Based on the latest shape model of Phobos from MEX mission, we firstly modeled the gravity field of Phobos, then the gravity coefficients were combined with some of the newest geophysical parameters to simulate the rotational motion of Phobos. To investigate how the elastic properties of Phobos affect its librational motion, we adopted various k2 into our numerical integration. Then the analysis was performed by iterating a frequency analysis and linear least-squares fit of Phobos’ physical librations. From this analysis, we identified the influence of k2 on the largest librational amplitude and its phase. Results. We showed the first ten periods of the librational angles and found that they agree well with the previous numerical results which Phobos was treated as a perfectly rigid body. We also found that the maximum amplitudes of the three parameters of libration are also close to the results from a rigid model, which is mainly due to the inclination of Phobos and moments of inertia. The other amplitudes are slightly different, since the physics contained in our model is different to that of a previous study, specifically, the different low-degree gravity coefficients and ephemeris. The libration in longitude τ has the same quadratic term with previous numerical study, which is consistent with the secular acceleration of Phobos falling onto Mars. We investigated the influence of the tidal Love number k2 on Phobos’ rotation and found a detectable amplitude changes (0.0005°) expected in the future space mission on τ, which provided a potential possibility to constrain the k2 of Phobos by observing its rotation. We also studied the influence of Phobos’ orbit accuracy on its libration and suggested a simultaneous integration of orbit and rotation in future work

Using Kerberos Tokens in Distributed Computing System at IHEP

The token-based certification method is spreading in the distributed computing system of high energy physics. More and more software and middleware are supporting tokens as one of the certification methods. As an example, WLCG has upgraded all the services to support WLCG tokens [1]. In IHEP (Institute of High Energy Physics in China), the Kerberos [2] token has been used as the main certification method in the local cluster. Naturally, it is selected as the certification method in the distributed computing system. In this case, a set of toolkits were developed or introduced to use Kerberos tokens in the distributed computing system, including token producer, token repository, token transfer and token client engine. The token producer is responsible for creating a token and publishing the token file to the token repository. The token repository stores all the latest token files and a refresh service periodically renews the lifetime of those tokens stored in the token repository. The token transfer brings the token file to the worker node. The token client engine initializes the token environment and renews the token’s lifetime on the worker node. With these toolkits, the jobs can run in any worker node in any site and use the Kerberos token to access other services, such as EOS [3] and the XRootd [4] proxy service. In IHEP, the Kerberos toolkit has been deployed in the distributed computing system. Currently, three experiments (LHAASO [5], BES [6] and HERD [7]) are using Kerberos tokens to remotely access the data in EOS or Lustre [8]

Monitoring motion and measuring relative position of the Chang'E-3 rover

Same-beam very long baseline interferometry observations were performed between the rover and the lander of Chang'E-3 and differential phase delay data were obtained with the minimum random error of about 0.03ps. These data were used to monitor the rover motions, as small as several centimeters, including movement, turning, and attitude adjustment. The relative position between the rover and the lander was precisely measured with an accuracy of 1m, which is an improvement of 10 times compared with that of the Apollo project

Resection of high-grade glioma involving language areas assisted by multimodal techniques under general anesthesia: a retrospective study

Abstract Background Multimodal techniques-assisted resection of glioma under general anesthesia (GA) has been shown to achieve similar clinical outcomes as awake craniotomy (AC) in some studies. In this study, we aim to validate the use of multimodal techniques can achieve the maximal safe resection of high-grade glioma involving language areas (HGILAs) under GA. Methods HGILAs cases were reviewed and collected between January 2009 and December 2020 in our center. Patients were separated into multimodal group (using neuronavigation, intraoperative MRI combined with direct electrical stimulation [DES] and neuromonitoring [IONM]) and conventional group (neuronavigation alone) and clinical outcomes were compared between groups. Studies of HGILAs were reviewed systematically and the meta-analysis results of previous (GA or AC) studies were compared with our results. Results Finally, there were 263 patients in multimodal group and 137 patients in conventional group. Compared to the conventional group, the multimodal group achieved the higher median EOR (100% versus 94.32%, P < 0.001) and rate of gross total resection (GTR) (73.8% versus 36.5%, P < 0.001) and the lower incidence of permanent language deficit (PLD) (9.5% versus 19.7%, P = 0.004). The multimodal group achieved the longer median PFS (16.8 versus 10.3 months, P < 0.001) and OS (23.7 versus 15.7 months, P < 0.001) than the conventional group. The multimodal group achieved a higher rate of GTR than the cohorts in previous multimodal studies under GA and AC (73.8% versus 55.7% [95%CI 32.0–79.3%] versus 53.4% [35.5–71.2%]). The multimodal group had a lower incidence of PLD than the cohorts in previous multimodal studies under GA (9.5% versus 14.0% [5.8–22.1%]) and our incidence of PLD was a little higher than that of previous multimodal studies under AC (9.5% versus 7.5% [3.7–11.2%]). Our multimodal group also achieved a relative longer survival than previous studies. Conclusions Surgery assisted by multimodal techniques can achieve maximal safe resection for HGILAs under GA. Further prospective studies are needed to compare GA with AC for HGILAs

Redevelopment of urban brownfield sites in China: motivation, history, policies and improved management

Rapid urbanisation in China has resulted in an increased demand for land in towns and cities. To upgrade and modernise, China has also moved many major industries from urban centres to less populated areas. With the high economic value of urban land, the transformation and utilisation of brownfield areas have become important economically and socially. The Chinese government has recognised the need for strong frameworks to safeguard soil and groundwater quality, with brownfield sites a key category for management. Strong scientific, regulatory and decision-making frameworks are needed and being adopted to ensure practical, careful and wise use of central and localised government resources, to manage the reuse and regeneration of these brownfield sites. This paper reviews the context, policies and management procedures of developing brownfield sites in countries with a history of brownfield management and discusses China’s current situation and priorities for brownfield governance and redevelopment. These include (1) clarification of brownfield site soil contamination risk control standards and risk assessment procedures, (2) the responsibilities of different national and local agencies, (3) the establishment of a national expert committee to advise on best practices, policy and process, (4) the use of registered brownfield databases at national, provincial, municipal and county levels, and (5) the set up of soil pollution prevention fund at the provincial level