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The CLP (Chinese Loess Plateau) is one of the most densely distributed landslides areas. The empirical relationships of the landslides in the CLP remain unclear, and its influencing factors are controversial. According to regional landslide data, this paper studies the relationships and discusses the factors affecting landslides in the CLP. The results show that the area (A) -volume (V) of landslides follows a power law trend described by V = 1.53 A1.19 and the frequency distribution range of H/L (height drop (H)/travel length (L)) is between 0.2 and 1.0, more specifically between 0.2 and 0.4, accounting for 26.1% of the total landslides, indicating that the landslides primarily belong to long run-out landslides. The function of V and H/L of the landslides is followed by H/L = 2.39 V−0.102. About 87% of the landslide is distributed within the equilibrium or mature stages of the watershed. The landslide’s size increases, and the slope of the landslides are steeper with an increase in HI (hypsometric integral). Meanwhile, the loess thickness, human activities, and slope effects on landslides induce landslide occurrence and have positive and negative effects on the landslides within the CLP. With climate change, the risk of landslides will increase in the CLP.

Objective To investigate the prevalence of cell phone addiction and the association with apps use and preference among medical students in China to offer suggestions for phone addiction prevention and management. Methods A total of 3058 medical undergraduate students from six medical universities/colleges located in five provinces of China were randomly sampled and interviewed. An adapted “Questionnaire of Mobile APP” from “Manolis/Roberts Cell-Phone Addiction Scale” was used to conduct the interview. Chi-squared (χ2) test and binary logistic regression analysis were used for data analysis. A database was built with EpiData 3.1, and statistical analysis was conducted using SPSS 23.0. Results Cell phone addiction was reported by 16.25% of medial undergraduates. Univariate analysis found statistical difference among addictive students with different genders, hukou status, monthly cell phone bills and in-love status. The following were reported as the risk factors for mobile addiction among medical students by logistic regression analysis: medical students who were female (odds ratio [OR]=1.704, 95% confidence interval [CI]=1.386, 2.095), were from urban (OR=1.307, 95% CI=1.046, 1.634), had boyfriend or girlfriend (OR=1.333, 95% CI=1.080, 1.646), used reading apps (OR=1.254, 95% CI=1.015, 1.549), were using reading apps (OR=1.254, 95% CI=1.015, 1.549), and were using chat apps (OR=2.222 , 95% CI=1.146, 4.310). Conclusion Medical students who are female, from urban, in-love, or frequent users of reading and chat apps may face a higher risk of cell phone addiction. Therefore, gender-specific and app type-specific interven-tions should be developed to intervene college students’ cell phone addiction.

Technologies bring a new era of content presentation for online teaching and learning. With more instructors adopting new tools to design online teaching materials, students are often put into learning contexts with certain new design components. Assessing learner experience and outcome in these contexts is challenging because of the complexity involved, as social and individual factors and behavioural impacts of using the new components have to be considered. Few studies have been reported in the literature identifying behavioural factors of learners' online learning experience when they interact with the content. Factors that affect learners' online learning experience, especially the affect factors, are less understood. This study therefore proposed and tested a model that explains the relationships among the affect factors and outcome behaviours of participants' online learning experience, taking into account individual difference, and employing a comparison based on a difference in content presentation. The data were collected from a professional training course offered by a university in the United States. The results support the assumption that time spent in study affects learning outcome and other outcome related behaviours. Also, positive relations between perceived quality of content design and outcome behaviour were found, indicating the effects of sense of presence and feeling of enjoyment on performance of creative tasks. The study intends to foster a deeper understanding of motivation and behaviours of online learning under innovative content design. [ABSTRACT FROM AUTHOR]

Disordered heap and unreasonable disposition of livestock manure in Erhai Lake Basin was the main pollution resource to Erhai. There exist problems in middle temperature biogas engineering, such as low gas production, unstable and easy to crusting. In order to control the farming wastes’ pollution and select the suitable middle temperature biogas engineering operation parameters for the anaerobic fermentation process in Erhai Lake basin, taking the dairy manure as sampling, this study investigated the effects of temperature, substrate concentration and inorganic stimulating factors on the middle temperature anaerobic fermentation efficiency. What’s more, the amount of trace elements was optimized with response surface method in the paper. The experimental conditions were 600 mL total volume of fermentation broth, 8% total solids content with a 30 days fermentation period. The single factor experiment of fermentation temperature selected three levels of 30, 35 and 45℃ for comparison. The results showed that the proportions of gas production in the first 20 days were respectively 93.7%, 93.5% and 95.3% accounted for the total gas production. The total gas production were respectively 0.187, 0.239 and 0.158 L/g at the end of the fermentation period. Thus, under the condition of fermentation temperature of 35℃, the gas production was greater than that at 30 and 45℃, it was conductive to the production of volatile fat acids (VFA), the reuse of methane bacteria, and the 4 kinds of microbial populations (aerobic acid-producing bacteria, anaerobic acid-producing bacteria, anaerobic cellulose decomposing microorganisms, methanogenic bacteria) were more than that at 30 and 45℃ in each stage of the fermentation. Therefore, fermentation temperature at 35℃ had a highest biogas production rate and a most proportion rate of functional microorganisms. The single factor experiment of substrate concentration selected 4 levels of 0, 10%, 20%, 30% and 40% for comparison. The total gas production were respectively 10 060, 10 622, 10 064, 9 358 and 8 558 mL at the end of the fermentation period. Therefore, the inoculation amount of 10% had the maximum total gas production, and the higher inoculation amount with a faster inoculation fermentation start-up speed. Meanwhile, the addition of inorganic stimulating factor can promote the whole fermentation process. It was investigated by the central composite experimental and response surface regression analysis. The results showed a fine effect between real values and predicted values of central composite experimental used quadratic polynomial fitting regression method. Response surface figures of Ni2+-Co2+, Fe2+-Ni2+ and Fe2+-Co2+ effects on accumulated biogas production were shown according to the central composite experimental results. And Ni2+-Co2+ and Fe2+-Ni 2+ did not have interaction，while Fe2+-Co2+ have interaction. Verification experiments were conducted, the results showed that the error between 3 parallel experimental values and predicted values was only 3.6%. Thus, the optimum concentrations was 5.00 mg/L Fe2+, 21.40 μg/L Ni2+, 28.82 μg/L Co2+. Under these conditions, it had a best gas production effect. Compared with the anaerobic fermentation system without addition of Fe2+, Ni2+ and Co2+, the biogas production was increased by 30%. The results will provide a basis for the normal operation of the rural farming manure anaerobic fermentation project in Erhai Lake basin. [ABSTRACT FROM AUTHOR]

The article is dedicated to the issues of physical, infectious and mental health of Ukrainian students in the 1920- th years, and analyzes the factors that directly make worse this condition. Separately we explore issues of power to prevent sexually transmitted epidemics, epidemics of typhoid, tuberculosis and other diseases. We also study such factors that have caused students' diseases as housing insecurity, lack of funds for the existence and complete lack of moral prohibitions- because of a radical change in the value of personality after the revolution and the civil war. [ABSTRACT FROM AUTHOR]