Both spike and local field potential (LFP) signals are two of the most important candidate signals for neural decoding. At present there are numerous studies on their decoding performance in mammals, but the decoding performance in birds is still not clear. We analyzed the decoding performance of both signals recorded from nidopallium caudolaterale area in six pigeons during the goal-directed decision-making task using the decoding algorithm combining leave-one-out and k-nearest neighbor (LOO-kNN). And the influence of the parameters, include the number of channels, the position and size of decoding window, and the nearest neighbor k value, on the decoding performance was also studied. The results in this study have shown that the two signals can effectively decode the movement intention of pigeons during the this task, but in contrast, the decoding performance of LFP signal is higher than that of spike signal and it is less affected by the number of channels. The best decoding window is in the second half of the goal-directed decision-making process, and the optimal decoding window size of LFP signal (0.3 s) is shorter than that of spike signal (1 s). For the LOO-kNN algorithm, the accuracy is inversely proportional to the k value. The smaller the k value is, the larger the accuracy of decoding is. The results in this study will help to parse the neural information processing mechanism of brain and also have reference value for brain-computer interface.
As an interface between external electronic devices and internal neural nuclei, microelectrodes play an important role in many fields, such as animal robots, deep brain stimulation and neural prostheses. Aiming at the problem of high price and complicated fabrication process of microelectrode, a microelectrode twisting machine based on open source electronic prototyping platform (Arduino) and three-dimensional printing technology was proposed, and its microelectrode fabrication performance and neural stimulation performance were verified. The results show that during the fabrication of microelectrodes, the number of positive twisting turns of the electrode wire should generally be set to about 1.8 times of its length, and the number of reverse twisting rings is independent of the length, generally about 5. Moreover, compared with the traditional instrument, the device is not only inexpensive and simple to manufacture, but also has good expandability. It has a positive significance for both the personalization and popularization of microelectrode fabrication and the reduction of experimental cost.
Objective To summarize the organization management and performance of volunteers taking part in the medical succor in People’s Hospital of Deyang City after 2 weeks of Wenchuan earthquake, in order to provide some reference for public health events in the future. Method Collecting some basic information, job flowing, workload, and management system of volunteers in the hospital from 12th to 26th, May, 2008, and so on, and then using Microsoft EXCEL to set up database for general analysis, in order to summarize management’s characteristics of volunteer organization and effects in hospital medical rescue. Result There are 6 838 persons that took part in the volunteer work, and this work can be divided into 3 phases according to the difference of the organization and management methods, they are 1 day later, 2-3 days later, 4-14 days later after earthquake. These volunteers assisted hospital finishing rescue, treatment and nursing for more than 1 870 wounded persons, transferring more than 441 wounded persons, and some works of logistic service, epidemic situation prevention and control, mentality intervention. Conclusion Different work tasks in different phases for volunteers after 2 weeks earthquake. Organizing and managing volunteers in different phases according to different work tasks to benefit the work performance.
Place cell with location tuning characteristics play an important role in brain spatial cognition and navigation, but there is relatively little research on place cell screening and its influencing factors. Taking pigeons as model animals, the screening process of pigeon place cell was given by using the spike signal in pigeon hippocampus under free activity. The effects of grid number and filter kernel size on the place field of place cells during the screening process were analyzed. The results from the real and simulation data showed that the proposed place cell screening method presented in this study could effectively screen out place cell, and the research found that the size of place field was basically inversely proportional to the number of grids divided, and was basically proportional to the size of Gaussian filter kernel in the overall trend. This result will not only help to determine the appropriate parameters in the place cell screening process, but also promote the research on the neural mechanism of spatial cognition and navigation of birds such as pigeons.
Animal localization and trajectory tracking are of great value for the study of brain spatial cognition and navigation neural mechanisms. However, traditional optical lens video positioning techniques are limited in their scope due to factors such as camera perspective. For pigeons with excellent spatial cognition and navigation abilities, based on the beacon positioning technology, a three-dimensional (3D) trajectory positioning and tracking method suitable for large indoor spaces was proposed, and the corresponding positioning principle and hardware structure were provided. The results of in vitro and in vivo experiments showed that the system could achieve centimeter-level positioning and trajectory tracking of pigeons in a space of 360 cm × 200 cm × 245 cm. Compared with traditional optical lens video positioning techniques, this system has the advantages of large space, high precision, and high response speed. It not only helps to study the neural mechanisms of pigeon 3D spatial cognition and navigation, but also has high reference value for trajectory tracking of other animals.
The neural stimulator is a core component of animal robots. While the control effect of animal robots is influenced by various factors, the performance of the neural stimulator plays a decisive role in regulating animal robots. In order to optimize animal robots, embedded neural stimulators had been developed using flexible printed circuit board technology. This innovation not only enabled the stimulator to generate parameter-adjustable biphasic current pulses through control signals, but also optimized its carrying mode, material, and size, overcoming the disadvantages of traditional backpack or head-inserted stimulators, which have poor concealment and are prone to infection. Static, in vitro, and in vivo performance tests of the stimulator demonstrated that it not only had precise pulse waveform output capability, but also was lightweight and small in size. It had excellent in vivo performance in both laboratory and outdoor environments. Our study has high practical significance for the application of animal robots.
Objective To suggest the establishment a publication plan for emergency situations in order to better manage and control information to the outside environment based on the experience of front-line hospital of grade III level A in Deyang during the response to the Wenchuan earthquake. Method We systematically collected statistical information published in the forms of news, columns, newspapers, periodicals, statistics, brief massage sent out by China Telecom ans China Mobile and banners in various media (CCTV, Sichuan TV, and inside hospital etc.) after Wenchuan earthquake.Result Within 40 days after the Wenchuan Earthquake, the People’s Hospital of Deyang City had reported rescue information for 181 times, sent 1 600 000 phone messages to the public, issued 7 476 pieces of family-search information, distributed 1 486 earthquake first-aid brochures, distributed 1 750 psychological brochures, compiled 12 periodicals called “Special Report for Earthquake Relief Effort”, and finished 3 periodicals called “Special Issue for Earthquake Relief Effort”; issued 319 articles, over 200pictures and videos on websites inside and outside of the hospital; issued over 60 pieces of news and 7 special topic documentaries in CCTV etc.; and issued over 70 pieces of news on People’s Daily. Conclusion During the Wenchuan earthquake, the People’s Hospital of Deyang City shows the rescue work to the public via effective publication mechanisms. News and information is transmitted fast and effectively between people from both upper and lower levels. However, there are weaknesses in working mechanisms and methods, which requires further study and consideration.