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Facial symmetry evaluation has always been a hot topic of concern for doctors who engage in the study of facial beauty disciplines such as orthodontics, dentistry, and plastic surgery. Although scholars at home and abroad have carried out much research on the evaluation of facial symmetry with a variety of emerging technologies and methods, there is still a lack of unified standards for the evaluation of facial asymmetry due to the complexity of the content and methods and individual subjectivity. Facial asymmetry involves changes in the length, width and height of the face. It is a complex dental and maxillofacial malformation whose early identification and accurate evaluation are particularly important. Clinically, in addition to the necessary dental and maxillofacial examinations, it is also necessary to evaluate facial asymmetry with the help of corresponding auxiliary methods. This paper gives a summary of the commonly used three-dimensional evaluation methods. The evaluation methods of facial asymmetry can be divided into 5 categories: qualitative analysis, quantitative analysis, dynamic analysis, mathematical analysis, and artificial intelligence analysis. After the analysis and summarization of the characteristics, advantages and limitations of each method in clinical applications, it is found that although these methods vary in accuracy, evaluation scope, diagnosis nature and calculation method, etc., the three-dimensional evaluation methods are more objective, more accurate and more convenient and will become the mainstream evaluation method for facial asymmetry with further development of three-dimensional measurement technologies.

In view of problems in existing rolling bearing fault diagnosis methods for coal mine rotating machinery, such as incomplete signal feature extraction, low fault diagnosis accuracy and low efficiency, a rolling bearing fault diagnosis method based on wavelet packet decomposition and particle swarm optimization BP neural network was proposed. The method includes signal feature extraction and fault type recognition. In the signal feature extraction part, the collected vibration signals of rolling bearing are decomposed by wavelet packet to obtain energy of each sub-frequency band and total energy of the signal. After normalization processing, feature vector representing state of rolling bearing is obtained. In the fault type recognition part, initial weight and threshold of BP neural network are optimized by particle swarm optimization to accelerate convergence speed of the network and avoid falling into local minimum. The experimental results show that the method improves fault diagnosis efficiency and accuracy of rolling bearing.

In view of problems that existing coal mine machinery online monitoring and diagnosis technology did not realize online extraction of fault characteristics and automatic identification of fault types, an online fault diagnosis and early warning system for coal mine rotating machinery based on LabVIEW was designed. The system analyzes vibration signal by means of spectrum analysis, power spectrum analysis, envelope spectrum analysis and cepstrum analysis, and obtains characteristic parameters of each component in running process of the rotating machine, and compares it with characteristic parameters in fault type database to realize fault diagnosis. Two kinds of fault diagnosis modes are designed including fine diagnosis and rough diagnosis, the two modes are associated by interlocking. If structural parameters of the main components of rotating machine are known, the fine diagnosis mode can be selected,otherwise, the rough diagnosis mode can be selected. Performance of the system is verified by simulating rotor unbalance fault of rotating machine, and the results show that the system can accurately identify faults and issue prompts with simple operation and high reliability.

The amid oxime modified Alzola imbricate dry powder( AI-g-AO) was synthesized by collecting wild Alzola imbricate from pond, making Alzola imbricate dry powder and modified with anidoxime group. The microstructure, element composition and structure of AI-g-AO before and after adsorption was characterized by Seaming Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy(XPS). The single factor experiments were used to study the effects of pH,reaction time, initial U concentration and adsorbent dosage on U adsorption by A--g-AO. The adsorption process was studied by pseudofirs-order and pseudo-second-order kinetic models, Langmuir and Freundfich isotherms. The results showed that the maximum U adsorption cupidity was 14. 98 under the conditions of 30, initial U concentration 15 mg/L, adsorbent: U solution = 1 g: 1 L, pH = 6. The pseudo-second-order kinetics and Langmrnr ssotherm were suitabee for the adsorption proces.. In conclusoon, A--g-AO was a good material for U biosorption. [ABSTRACT FROM AUTHOR]

As a kind of ubiquitous energy in natural environment, environmental vibration has the characteristics of random amplitude, direction reciprocating, and low frequency. Firstly, an electromagnetic energy harvester using mechanical rectifier is designed, which can rectify the environmental vibration into one-way rotation of the shaft to realize the output of the direct current electric energy. Secondly, the dynamical model of the energy harvester is built and its output characteristics are derived; and the voltage output characteristics under different vibration amplitudes, frequencies and load resistance conditions are numerically analyzed. Finally, the experimental tests on the output characteristics of the energy harvester under determined vibration input are conducted. The results show that this device can transfer the environmental vibration into continuous direct current electric energy output, and the amplitude, frequency and load resistance all have effects on the output voltage of the harvester. When the vibration amplitude is 50 mm, the frequency is 0.8 Hz, and the load resistance is 100 Ω, the peak value of the output voltage is 14.2 V and the instantaneous power can reach 2 W. [ABSTRACT FROM AUTHOR]

The research of the joint strength of adhesives between the wing of aircraft and the anti-icing/de-icing device was proposed. A simple measuring equipment, which can be used to measure the tensile shear strength and 180° peel strength, was de signed. According to national standards, EA9303 and J-200-1A adhesives were used to manufactured the specimens for test The 2A12 aluminum alloy and carbon fiber bidirectional fabric were selected as materials of rigid and flexible specimens, respectively. Finally, the equipment was used to carry out the joint strength of the specimens. The results demonstrated that the tensile shear strengths of the adhesives were 14.5 MPa and 7.7 MPa respectively. The peel strengths were 4.58 kN/m and 4.61 kN/m in the direction of 180° respectively. [ABSTRACT FROM AUTHOR]

Objective: To analyze variation of ISL1 gene and explore its functional characteristics in relation with congenital heart defect (CHD)., Methods: Clinical data and peripheral blood samples of 194 CHD patients and 232 healthy controls were collected for the extraction of genomic DNA. The coding exons and flanking intronic regions of the ISL1 gene were sequenced. Expression plasmid for the wild-type ISL1 gene ISL1-pcDNA3.1 was constructed, and the corresponding variants were obtained by site-specific mutagenesis. The gene expression plasmid was transfected into CHO cells with liposome, and the functional characteristics of ISL1 variant were studied by double luciferase reporter gene analysis., Results: A novel variant of the ISL1 gene c.499C>T (p.Q167X) was detected in a patient with sporadic CHD. Functional study showed that the variant has lost its transcriptional activation function for the MEF2C promoter., Conclusion: A novel variant of the ISL1 gene related to CHD has been identified. The defect of ISL1 gene may underlay the pathogenesis for a proportion of CHD.

The exogenous gene expression and its impacts on the bacterial population are important to study quorum sensing systems and synthetic biology industry. However, the behavior of exogenous protein expressing bacteria remains poorly understood. To find out which factors are playing a critical role in the growth of population and exogenous gene expression, we measured Lux-type receptor-regulated exogenous gene expression under the induction of N-acyl homoserine lactone (N-AHL) signaling molecules and impacts on the bacterial population dynamics after such stimulation. To analyze the cause of fitness burden of bacteria, we set up a hypothetical mathematical model. Previous studies often arrogate this phenomenon to the synthesis cost and the toxicity of N-AHL signaling molecule. However, we suggested another possible cause of the fitness burden.