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In this paper, firstly, according to the conditions of the growth of the tourism industry in the whole region and the requirements of the growth mechanism, the time sequence of the growth of the tourism industry in the whole region is divided into three phases: the initial start-up phase, the mid-growth phase and the late maturity phase, and puts forward the strategy of the growth of the tourism industry in the whole region. Then, on the basis of the transfer matrix model, according to the law of tourism industry development to determine the tourism industry’s independent variable power function, considering the impact of economic policy and monetary policy on the development of the tourism industry, the need to eliminate the direct effect of the tourism industry independent variable, and then construct the transfer matrix based on the spatial distribution of the tourism industry analytical model and hierarchical system analytical model, and the whole region of the tourism industry in Hubei Province for example research and analysis. The results show that on the model analysis, the prediction accuracy of VM and FM varies among five different groups: purchase>tour> food>travel>housing. In the tourism industry, the correlation coefficient between “food and beverage, accommodation, shopping and entertainment” is around 0.95. This study not only contributes to the green and sustainable development of China’s tourism industry but also is an important step in promoting the construction of ecological civilization.

In order to prepare lightweight high entropy alloy (LHEA) with suitable microstructure and excellent properties, Ti3V2NbAlxNiy LHEA with different Al and Ni ratios were prepared on TC4 substrate using laser cladding technology. Its microstructure, friction, and wear properties were studied, and the effect of adding a small amount of MoB ceramic particles on its microstructure and properties was discussed. The results show that the phases of Ti3V2NbAl0.5Ni0.5, Ti3V2NbAl0.5 and Ti3V2NbNi0.5 coatings are composed of a single body-centered cubic crystal (BCC), while the second phase A15 is formed in Ti3V2NbAl0.5Ni0.5/MoB coatings. Compared with the hardness of the matrix, the hardness of four coatings has been improved. The wear forms of four coatings are mainly adhesive wear, with adhesive layer and a small amount of oxide layer distributed in the wear marks, and furrow characteristics caused by slight abrasive wear are also observed in the wear marks. Compared with the matrix, the wear rate of Ti3V2NbAl0.5Ni0.5/MoB coating is greatly reduced, and the wear rate of Ti3V2NbAl0.5Ni0.5/MoB coating is reduced by 51.1%. The LHEA in this paper has good wear resistance and can be used as a protective coating for TC4 parts in aerospace, national defense equipment manufacturing and other fields. [ABSTRACT FROM AUTHOR]

Objective To explore the influence of the SmartClip self-ligating bracket and traditional metal bi-wing brackets on plaque control and to provide a reference for the oral healthcare of orthodontic patients.Methods The patients were divided into the SmartClip self-ligating bracket group, the metal bi-wing bracket group, and the control group, consisting of untreated volunteers, and the patients were examined before treatment, 1 month after the treatment started, 3 months after the treatment started, and when the treatment ended. The oral hygiene status was recorded at four time points, and the plaque index of the following six teeth was compared among the time points: the upper-right central incisor (UR1), the lower-left central incisor (LL1), the upper-right first molar (UR6), the lower-left first molar (LL6), and the upper left canine (UL3) and the lower-right canine (LR3).Results Compared with before treatment, after first month, third month and end of treatment the plaque index of LL1, LR3, LL6 and UR6 in both the SmartClip self-ligating bracket group and the traditional metal bi-wing bracket group was increased, and the difference was statistically significant (P < 0.05). There was no significant difference in PLI index between the end of treatment and 3 months after orthodontic treatment (P > 0.05). There was no statistically significant difference in PLI index in the control group at each time period (P > 0.05). After three months of orthodontic treatment, the plaque index of LL1 and LR3 in the SmartClip self-ligating bracket group was higher than that in the traditional metal bi-wing bracket group, and the difference was statistically significant (P < 0.05).Conclusion Lower anterior and posterior areas are susceptible to plaque accumulation in treatment with fixed orthodontic appliances. The SmartClip self-ligating bracket system has no advantage over the traditional metal bi-wing bracket in terms of oral hygiene.

Objective To study the relation between the upper first molar root tips and the maxillary sinus floor in patients with different vertical facial patterns using cone⁃beam computed tomography (CBCT) and to explore the refer⁃ ence data for safe clinical orthodontic treatments. Methods Three⁃dimensional images were reconstructed from CBCT data. The CBCT data from 120 adolescents and adults were divided into three groups (low⁃angle group, average⁃angle group, high⁃angle group) based on vertical facial type. For each subject, the distance from the maxillary sinus floor to the upper first molar root tips was measured, and the types of contacts were classified. ANOVA and LSD t tests were used for statistical comparisons and performed using SPSS 19.0. Results Of the 120 samples, only 27% of the upper first molar root tips lost their contacts with the maxillary sinus floor, and the other 73% of the root tips contacted the si⁃ nus to different extents. Significant differences in the distances from the maxillary sinus floor to the upper first molar root tips were found for different vertical facial types (P < 0.05). The high⁃angle group had the lowest sinus floor, rela⁃ tive to the root tips, of the three adult groups (P < 0.05). In the adult group with a low angle, the measured value for the palatal root tips was the lowest and was significantly different from those in the other groups (P < 0.05). Conclusion Seventy⁃three percent of the upper first molar root tips contacted the maxillary sinus floor. The maxillary sinus floor tended to be lower relative to the first molar root tips in patients with a high⁃angle facial pattern than in others. The roots protruded into the sinus to a greater extent.