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Although autologous nerve transplantation is the gold standard for treating peripheral nerve defects, it has many clinical limitations. As an alternative, various tissue-engineered nerve grafts have been developed to substitute for autologous nerves. In this study, a novel nerve graft composed of chitin scaffolds and a small autologous nerve was used to repair sciatic nerve defects in rats. The novel nerve graft greatly facilitated regeneration of the sciatic nerve and myelin sheath, reduced atrophy of the target muscle, and effectively restored neurological function. When the epineurium of the small autogenous nerve was removed, the degree of nerve regeneration was similar to that which occurs after autogenous nerve transplantation. These findings suggest that our novel nerve graft might eventually be a new option for the construction of tissue-engineered nerve scaffolds. The study was approved by the Research Ethics Committee of Peking University People’s Hospital (approval No. 2019PHE27) on October 18, 2019.

By collecting the magnetic field information of each spatial point, we can build a magnetic field fingerprint map. When the user is positioning, the magnetic field measured by the sensor is matched with the magnetic field fingerprint map to identify the user’s location. However, since the magnetic field is easily affected by external magnetic fields and magnetic storms, which can lead to “local temporal-spatial variation”, it is difficult to construct a stable and accurate magnetic field fingerprint map for indoor positioning. This research proposes a new magnetic indoor positioning method, which combines a magnetic sensor array composed of three magnetic sensors and a recurrent probabilistic neural network (RPNN) to realize a high-precision indoor positioning system. The magnetic sensor array can detect subtle magnetic anomalies and spatial variations to improve the stability and accuracy of magnetic field fingerprint maps, and the RPNN model is built for recognizing magnetic field fingerprint. We implement an embedded magnetic sensor array positioning system, which is evaluated in an experimental environment. Our method can reduce the noise caused by the spatial-temporal variation of the magnetic field, thus greatly improving the indoor positioning accuracy, reaching an average positioning accuracy of 0.78 m.

In the application of video surveillance, reliable people detection and tracking are always challenging tasks. The conventional single-camera surveillance system may encounter difficulties such as narrow-angle of view and dead space. In this paper, we proposed multi-cameras network architecture with an inter-camera hand-off protocol for cooperative people tracking. We use the YOLO model to detect multiple people in the video scene and incorporate the particle swarm optimization algorithm to track the person movement. When a person leaves the area covered by a camera and enters an area covered by another camera, these cameras can exchange relevant information for uninterrupted tracking. The motion smoothness (MS) metrics is proposed for evaluating the tracking quality of multi-camera networking system. We used a three-camera system for two persons tracking in overlapping scene for experimental evaluation. Most tracking person offsets at different frames were lower than 30 pixels. Only 0.15% of the frames showed abrupt increases in offsets pixel. The experiment results reveal that our multi-camera system achieves robust, smooth tracking performance.

Medical adherence is often higher in clinical trials than in real world practice. The aim of this study was to investigate the effects of traditional Chinese medicine (TCM) on medical adherence to hormonal therapy (HT) and survival outcome in ER (+) breast cancer patients in Taiwan.Using a nationwide longitudinal population-based database, we enrolled patients with newly diagnosed ER-positive breast cancer who had received HT, and followed for up to 5 years (N = 872). Medication adherence in terms of medication possession ratios (MPR) and patient outcome were evaluated with or without TCM exposure. We applied logistic regression and Cox proportional hazards (PH) analysis to identify factors, including TCM exposure, associated with adherence to HT and mortality.MPR to HT in general decreased over the 5-year period post breast cancer diagnosis. Both TCM and MPR to HT ≥ 80% were significantly associated with reduced risk of breast cancer-associated mortality. Subgroup analysis revealed that TCM annual visits ≥ 3 times with CHP prescription 1~90 days per year affected mortality reduction most significantly (HR: 0.26; 95% CI = 0.08-0.83; p 0.05) compared to other TCM use. In contrast, using TCM (either short-term or long-term) was not associated with MPR in HT.Our results supported the potential advantage of TCM on breast cancer-associated mortality, whereas TCM use does not compromise medical adherence to HT. This study offers important insights in integrative therapy for HT in patients with estrogen receptor (+) breast cancer.

This paper mainly introduces the application of 3D scanning modeling technology and 3D printing technology in the reproduction of fine bronze cultural relics. We apply 3D scanning, point cloud data processing, 3D mod-eling, 3D printing and other key technologies in the field of fine cultural relics reproduction. At the same time, reconstruction technology can be used to reconstruct and restore the damaged parts of excavated cultural relics in three dimensions. We will output the 3D solid model of the copied cultural relic, input the 3D printer to print the high-quality reproduction mold consistent with the original cultural relic, and finally complete the overall casting of the printing mold.

This paper analyzes the life of a kind of conveyor belt, based on the theory of the hydraulic tensioning device. Hydraulic tensioning device is a kind of machine which detects the real-time force in the conveyor belt. When the force is lower than the enactment value, the device will tension the belt to make it lager, in case of the belt skids. When the force is higher than the enactment value, the device will stop tensioning the belt. Based on the relationship between the effective strain and the life of the conveyor belt, simplify the real problem. Draw a curve of the relationship between the effective strain and the life of the conveyor belt by Matlab which can educe the stop tensioning value. Based on the theory of classical mechanics, the paper gives out the start tensioning value. At last, this paper gives out the reasonable range of the strain of the conveyor belt.

For most of the cities will appear traffic congestion on the work the peak of the big gap in both directions of traffic between the same road sections in china, comparative analysis of the collected traffic flow on urban road sections on the flow and the value of road occupation rate and statistical derivation.Proposed the concept of restructuring on the road environment. Introduce the reorganization of the basic principles and the rule of the lane change

This paper demonstrates the one-dimensional computa- tional results of the propagation of Gaussian electromagnetic pulse through dielectric slabs of finite thickness with variation in permittiv- ity. The numerical approach used is the characteristic-based method solving the time-domain Maxwell curl equations involved with non- uniform permittivity. In the numerical model, all dielectric slabs are assumed to be isotropic, lossless, and linear. The permittivity of dielec- tric slab may increase or decrease linearly or sinusoidally. The numer- ical permittivity is finely discretized such that the variation between two adjacent grids is so small that the non-uniform permittivity is as- sumed to be piecewise continuous and consequently can be modeled as an individual block. The numerical results of various electric fields, both in the time- and frequency-domain, are presented and compared based on the dielectric slab of constant permittivity for close investi- gating the effects of the non-uniform permittivity distribution on the electromagnetic fields. It is also shown that under certain arrange- ment of Gaussian electromagnetic pulse and dielectric slab thickness the pattern of field propagation, reflection and transmission, can be reproduced in different time scales and frequency ranges.

This paper presents a double-layer leaky-wave microstrip antenna that is entirely planar for easy fabrication. The cavity model and the full-wave spectral domain method are used to analyze the proposed structure. The results from these two approaches agree well with experimental data. The planar structure makes the leaky-wave antenna convenient for implementation in a monolithic microwave integrated circuit (MMIC) environment. Also, due to the flexibility of the microstrip structure, the geometrical shape can be modified for other desirable radiation patterns.

The purpose of this paper is to analyze the Z-shape micro strip antenna for dual-band operation. Based on the cavity model, the whole individual antenna cavity is first divided into three regions. The relationships between these cavities are established by boundary conditions. After the employment of Moment Method, the antenna parameters of two lowest modes are obtained for comparisons. The agreement of resonant frequencies and electric fields from theory and simulations verifies the design concept. The resonant frequencies from simulation and experiment also confirm the validity of the theoretical analysis. The data show that acceptable radiations of two modes are with the pattern of single beam. This Z-shape design offers an alternative simple choice to design a dual-band antenna.

For the demands of systems integration in wireless communication, this paper designs a Z-shape microstrip antenna for dual-band operation. The design concept is to bend the patch in order to adjust direction of magnetic current which determines the mode along symmetric longitudinal axis. Therefore, this magnetic current will contribute the same polarization of electric field as those along horizontal axis. This antenna can offer two acceptable modes. The resonant frequency obtained by the theory, simulation, and experiment confirm accuracy of simulation data. Simulation data does not only verify concept feasibility, but also investigate antenna characteristics. The structure of this antenna is relatively simple, and design concept is novel. However, more work to improve the radiation at high frequency by structure parameters variation is another work in future research.

A novel electronic beam steering is achieved by varying the amplitude of each radiating element in a microstrip array on a curved surface. PIN diodes are used to turn on the radiating patches facing in the intended direction while turning off all other patches. Since the amplitude-varying antenna does not use expensive phase shifters, the resultant beam-steering system is much less expensive than conventional phased-array antennas. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 386–387, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10771