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The traditional trajectory prediction models have the problems of large model simplification and less consideration. Combined with the characteristics of flight trajectory continuity, time series and interactivity, a trajectory prediction model based on bidirectional long short term memory(Bi-LSTM) neural network is proposed. The position, heading, pitch, roll and relative information of the intruder UAV are simultaneously used as the input of the trajectory prediction model, which is more in line with the true trajectory change law. The established Bi-LSTM based trajectory prediction model is trained with adaptive learning rate learning algorithm considering momentum and speed, and performed with simulation contrastive analysis with trajectory prediction model based on Elman neural network. The results show that, compared with the trajectory prediction model based on Elman neural network, the average absolute error of the proposed model predicted by 200 points in different directions is less than 4 m, the 3D prediction effect is better, and can perform the trajectory prediction more accurately.

Objective: To illustrate the role of epidermal growth factor (EGF) secreted by astrocytes in the process of tacrolimus (FK506) in promoting neurite outgrowth., Methods: The spinal cord astrocytes and neuronal cells were isolated respectively from 2-day-old Sprague Dawley (SD) rats and 15-day SD pregnant rats, and cultured in vitro and identified by immunofluorescence staining. The spinal cord astrocytes were cultured with 20 µmol/L FK506 medium in the experimental group, and with FK506 free medium in the control group. The supernatant was collected after 24 hours for preparing conditioned medium, and astrocytes were collected. EGF proteins in the conditioned medium were detected with ELISA, and EGF gene expressions of astrocytes were detected with real-time quantitative PCR (RT-qPCR). The spinal cord neurons were cultured respectively with conditioned medium from the experimental group (FK506-CM) and the control group (C-CM) in group A and group B, also with neutralized C-CM and neutralized FK506-CM with anti-EGF neutralizing antibodies in group C and group D. Both the total neurite length and the longest neurite length were measured and compared among groups., Results: Both astrocytes and neurons were confirmed by immunofluorescence staining. The EGF content of experimental group (0.241 ± 0.044) was significantly higher than that of the control group (0.166 ± 0.014) (t = 3.93, P = 0.01); EGF gene expression of the experimental group (1.12 ± 0.25) was significantly higher than that of the control group (0.46 ± 0.11) (t = 5.78, P = 0.00). The neurite length measurement displayed that the total neurite length and the longest neurite length of groups C and D were significantly shorter than those of groups A and B (P < 0.05). Both the total and longest neurite length of group A were significantly longer than those of group B (P < 0.05), but no significant difference was shown between groups C and D (P > 0.05)., Conclusion: The EGF secreted by spinal cord astrocytes can promote the neurite outgrowth. So spinal cord astrocytes can be used as an important intermediary target of FK506 to promote the recovery of neurological function.

Objective: To investigate the feasibility of establishment of physiological micturition reflex arc by simultaneously reconstructing the sensory and the motorial nerve of atonic bladder after spinal cord injury., Methods: Eight 1-year-old Beegle male canine were selected, weighing 7-12 kg. The left side was the experimental side, while the right side was the control side. Epidural microanastomosis of vertebral canal of the left L7 ventral root to S2 ventral root and L7 dorsal root to S2 dorsal root was performed to reconstruct the sensory and the motorial function of atomic bladder. The right side was used as a control without treatment. The new motor-to-motor, and sensory-to-sensory physiological bladder reflex pathway were established after 12 months of axonal regeneration. Then S1-4 segmental spinal cord was destroyed for preparation of complete paraplegia. The electrophysiological examination and the bladder pressure were detected before and after paraplegia. The canine micturition was observed for 3 months after paraplegia. Neurohistological observation was performed after canine sacrifice., Results: Of 8 canine, 7 canine survived. After paraplegia, canines displayed urinary incontinence and frequent micturition at first, nocturnal continence was achieved gradually without frequent micturition after 1 month. Urinary infection at different degrees occurred in 3 canines and was controlled after Norfloxacin was administered orally. The bladder pressure increased to (1.00 +/- 0.13) kPa, (0.90 +/- 0.12) kPa after trains of stimulation (300 mV, 0.3 ms, 20 Hz, 5 seconds) of S2 dorsal root at the experimental side before and after paraplegia respectively, showing no significant difference (P > 0.05). It increased to (1.90 +/- 0.10) kPa after the same train of stimulation of S2 dorsal root at control side. There was significant difference between the experimental side and the control side (P < 0.01). Single stimulation (300 mV, 0.3 ms) of the S2 dorsal root at the experimental side resulted in evoked potentials recorded from the left S2 ventral root before and after paraplegia. Before and after paraplegia, the amplitudes of the evoked potentials were (0.68 +/- 0.11) mV and (0.60 +/- 0.08) mV respectively, showing no significant difference (P > 0.05). It was (1.21 +/- 0.13) mV while stimulating at the control side. There was significant difference between the experimental side and the control side (P < 0.01). Neurofibra of L7 dorsal and ventral root grew into S2 dorsal and ventral root on tissue slice under light microscope., Conclusion: Reconstruction of the bladder physiological micturition reflex arc is feasible by anastomosis of sacral dorsal and ventral root below injured spinal plane with the suprasacral survival dorsal and ventral root above the plane respectively for restoration of atonic bladder after spinal cord injury.

Objective: To investigate effects of the basic fibroblast growth factor (bFGF) and fibronection (FN) on the osteoblast adhesion on the bio-derived bone., Methods: The third generation of the osteoblast was treated with bFGF 0. 1, 1, 10, and 100 ng/ml, respectively, and then was seeded in the bio-derived bone, which had been modified with FN 0.1, 1, 10, and 100 microg/ml, or Polylysine, respectively. The cell adhesion was measured by the MTT assay. The cell density and the cell appearance were observed by the scanning electron microscope. The above-mentioned procedures were repeated by an application of the GRGDS peptide., Results: Both FN and bFGF could enhance the osteoblast adhesion efficiency on the bio-derived bone (P < 0.05). However, the osteoblast adhesion efficiency could be significantly strengthened by a combined use of FN and bFGF. FN and bFGF had a significant synergistic effect in statistics (P < 0.01), but Polylysine and bFGF had no such synergistic effect (P > 0.05). The combined use of FN and bFGF had a better effect on the cell density and the cell appearance than either of them when observed with the scanning electron microscope. Adhesion efficiency generated by the combined use of FN and bFGF was significantly blocked by the application of the GRGDS peptide., Conclusion: The combined use of FN and bFGF has a significant synergistic effect on the osteoblast adhesion efficiency on the bio-derived bone. This effect is probably mediated by the RGD-integrin alpha5beta1 pathway.