Search

Objective To understand the prevalence and annual change trend of Internet addiction among students aged 11 and 22 in Inner Mongolia in 2019 and 2021, and to explore the influencing factors of Internet addiction behavior, so as to provide reference basis for the prevention of Internet addiction among students. Methods Students were selected from 12 cities of Inner Mongolia Autonomous Region by stratified cluster random sampling. Internet addiction disorder was determined according to the items of "surveillance and intervention of common diseases and health influencing factors of students in China". Logistic regression method was used to analyze the relationship between Internet addiction and behavioral factors. Results The prevalence of Internet addiction among students aged 11 to 22 years in Inner Mongolia in 2019 was 1.92%, 2.50%, and 2.21%, respectively. Logistic regression analysis showed that vocational high school (OR=1.347, 95%CI: 1.083-1.675), single parent family (OR=1.279, 95% CI: 1.090-1.500), reconstituted family (OR=1326, 95% CI: 1.041-1.690), bullying (OR=1.755, 95% CI: 1.443-2.135), depression (OR=3.557, 95% CI: 3.146-4.021), fighting (OR=3.374, 95% CI: 2.512-4.531), sugary drinks (OR=2.182. 95% CI:1.753-2.716), and eating fried food (OR=2.398, 95% CI: 1.908-3.014) were the risk factor of Internet addiction. Outdoor activities for 2 hours (OR= 0.620, 95% CI: 0.530-0.726), non-smoking (OR=0.553, 95% CI: 0.476-0.643), and non-drinking (OR=0.581, 95% CI: 0.507-0.666) were the protective factors of Internet addiction. Conclusion The current situation of Internet addiction among students in Inner Mongolia is not optimistic. Attention should be paid to bullying, depression, reconstituted families, fighting students, and vocational high school students. Outdoor activities for 1 to 2 hours a day, reducing the intake of sugary drinks and fried foods, and no smoking and drinking can effectively reduce the incidence of Internet addiction. [ABSTRACT FROM AUTHOR]

Application of the AUSMV (advection upstream splitting method V) scheme was extended from gas dynamics to transient ID isothermal gas-liquid two-phase pipe flow problems. The method of numerical flux for the DFM (drift flux model) constructed with the AUSMV scheme and treatment of boundary cells were stated for the simulations. The numerical calculation method of 2nd-order accuracy in time and space was obtained with the classical Runge-Kutta method and the monotonous MUSCL (monotone upstream-centred schemes for conservation laws) technique combined with the Van Leer limiter. The numerical examples including the Zuber-Findlay shock tube problem and the variable mass flow problems with complex slip relations were conducted and comparatively discussed. The results indicate that the proposed AUSMV scheme, with advantages of high efficiency, high precision and low effects of dissipation and dispersion, accurately details the discontinuities of ID gas-liquid two-phase flow problems under low flow velocity conditions. [ABSTRACT FROM AUTHOR]

Application of the AUSMV (advection upstream splitting method V) scheme was extended from gas dynamics to transient 1D isothermal gas-liquid two-phase pipe flow problems. The method of numerical flux for the DFM (drift flux model) constructed with the AUSMV scheme and treatment of boundary cells were stated for the simulations. The numerical calculation method of 2nd-order accuracy in time and space was obtained with the classical Runge-Kutta method and the monotonous MUSCL (monotone upstream-centred schemes for conservation laws) technique combined with the Van Leer limiter. The numerical examples including the Zuber-Findlay shock tube problem and the variable mass flow problems with complex slip relations were conducted and comparatively discussed. The results indicate that the proposed AUSMV scheme, with advantages of high efficiency, high precision and low effects of dissipation and dispersion, accurately details the discontinuities of 1D gas-liquid two-phase flow problems under low flow velocity conditions. [ABSTRACT FROM AUTHOR]

In order to study the selectivity of flocculant between coal and kaolinite in selective flocculation floatation, the adsorption isotherm and adsorbance difference of polyacrylamide onto kaolinite and coal was investigated. The laser particle size analyzer was used to measure the floes size distribution of coal and kaolinite in different polyacrylamide solution. Hydrodynamic radius and adsorption radius of polyacrylamide molecular were calculated to discuss its adsorption conformation. The adsorbance of anionic polyacrylamide onto coal is higher than that of kaolinite. The adsorbance difference between coal and kaolinite decreases with the increase of polyacrylamide molecular weight. The adsorbance of cationic polyacrylamide onto kaolinite is higher than that of coal, and the adsorbance difference is lower. Selectivity of anionic polyacrylamide with molecular weight 3x106 is the best. Adsorption process of coal and kaolinite is more accord with Langmuir adsorption model. The coal adsorbance of this polyacrylamide is 2.15 times larger than that of kaolinite. The indicators of particle size distribution, d10, d50 and d90 of coal floes are 8.42, 2.60 and 2.75 times of kaolinite floes, respectively. The calculated adsorption radius of polyacrylamide molecular is lower than its hydrodynamic radius. When different polyacrylamide is absorbed onto different mineral surfaces, the effect of compression or penetration with different intensity of polyacrylamide occurres. [ABSTRACT FROM AUTHOR]

Most insects mainly perceive external environment throught ordor, to maintain life activities. Research on the olfactory neuromechanism and molecular mechanism is important to make clear the function of insect olfactory cognitive and the bionics research by neural mechanisms of insect ordor perception. In recent years, the technology of neurobiology and molecular biology have great progress, especially the research on olfactory neuralstructure and molecular mechanism of insect odor perception, which makes a deeper research on the insect olfactory neural loop and molecular. According to the latest research results, this review focuses on the insect olfactory neuralstructure, molecular mechanism and the odor signal pathway including antennal sensilla, antennal lobe and mushroom body, as well as molecular mechanism of ordor perception and olfactory singnal pathway. Review results: Insect cognition of smell is realized through the olfactory nerve system in the brain nerve structure of multilayer signal processing, including antennal sensilla, antennal lob, and mushroom body. When the external odor molecules into the antennal sensilla, the sense of odour recognition protein specific device to odor molecules carrying reach the olfactory receptor neurons dendritic membrane receptor, odor molecules combination with the specific odor receptor produces electrical signal, with the action potentials through the ORN axon to the AL. In the antennal lobe after olfactory glomeruli has selective processing of olfactory information, then the PNs drlivery identification and classification odor information to MB and LH of the central nervous system, to achieve recognition and perception of odor. Although, recent studies of insect odorant cognitive neuroscience has made great progress, we believe that the results of the present study is not completely clarified the neural mechanisms of odorant perception. There are a lot of problems, such as, how lots of the olfactory glomeruli of antennal lobe encode the odor information introduction by the olfactory receptor. We need further study. In order to clarify these problems, we need to improve the existing experimental techniques, strengthening the electrophysiology and molecular neurobiology combination, neural mechanism of odor recognition from the molecular level may be the focus of study in the future. [ABSTRACT FROM AUTHOR]

The quantitative prediction of thin-bed thickness is the one of important problems of the geophysicist's research. These methods is often implemented through establishing the relationships between thin-bed thickness and seismic dominant amplitude, frequency or other attributes, and then used to directly or indirectly predict thin-bed thickness. These relationships are always dependent on the characteristics of selected seismic wavelet, which is an approximation of realistic wavelet. However, the calculation of selected wavelets is subject to the influence of seismic data quality and its accuracy is not sufficient. A more realistic wavelet was presented in this paper using the solution of vis-coelastic wave equations. The first order approximation formula was established to describe the relationship between the thin-bed thickness and the amplitude of compound seismic waves reflected from top and bottom of thin-bed. Compared with the Widess' method, the proposed method has a higher precision. [ABSTRACT FROM AUTHOR]