50 research outputs found

    Research on the evolution of express packaging recycling strategy considering virtual incentives and heterogeneous subsidies

    No full text
    Abstract With the growth of e-commerce business volume, a large amount of express packaging waste is generated, causing certain damage to the environment. In response to this problem, the China Post Bureau pointed out the plan to strengthen express packaging recycling, and large e-commerce platforms such as JD.com have taken actions. Starting from this background, this paper uses a tripartite evolutionary game model to study the strategies evolution of consumers, e-commerce companies and e-commerce platforms. At the same time, the model considers the influence of platform virtual incentives and heterogeneous subsidies on equilibrium evolution. The study found that with the increase of virtual incentives from the platform to consumers, consumers converge to the strategy of "participating" in express packaging recycling faster and faster. When the assumption of participation constraints for cosumers is relaxed, the virtual incentives of the platform are still effective, but it will be affected by the initial willingness of consumers; when the e-commerce platform uses a single method to subsidize, it can effectively encourage e-commerce companies to use green packaging items. Compared with direct subsidize, the policy flexibility of the discount coefficient is stronger, in addition, moderate double subsidies can also achieve the same effect, and the e-commerce platform can make decisions based on the actual situation. The cyclical fluctuations in the strategies of consumers and e-commerce companies in the case of high additional profit coefficients of e-commerce companies may be the reason why the current express packaging recycling program is not effective. In addition, this article also discusses the influence of other parameters on the equilibrium evolution, and gives targeted countermeasures

    Accumulation threshold and exploration potential of deep basin oil in the Songliao Basin

    No full text
    To further understand the accumulation mechanism and distribution rules of deep basin oil, the laboratory physical simulation experiment is conducted for water-sealed oil in sand columns of different grain sizes, and the water-sealed oil mechanism and the accumulation threshold of deep basin oil are analyzed. Stable deep basin oil can be formed under laboratory conditions. The accumulation threshold of deep basin oil mainly depends on the pore throat radius of oil-bearing sand layer as well as the oil/water interfacial tension and strata dip under such conditions. The accumulation threshold and its main controlling factors of the deep basin reservoir in the Fuyang oil layer are studied, and the prediction model of deep basin reservoir boundaries is established: the porosity is less than 11%, the permeability is less than 1×10−3 ÎŒm2, the largest pore throat radius is less than 6.2 ÎŒm, and the burial depth is 1800-2100 m, located at the lower positions of syncline or slope, and good source rock in Qing-1 Member is developed, with obviously abnormal pressure. Three “sweet spot” areas favorable for deep basin oil in the Songliao Basin are determined, namely south Liangjing area, east Haituozi area, and west Qian'an area. The predicted deep basin oil potential in these three areas is 0.317 billion tons. The total proved resources of deep basin oil in the Songliao Basin are 1.575 billion tons, with good exploration potential. Key words: deep basin oil, simulation experiment, accumulation threshold, Fuyang oil layer, Songliao Basi

    Mechanical Properties of the Vertical Joints of Prefabricated Underground Silo Steel Plate Concrete Wall

    No full text
    Reliable joint connection is key to designing prefabricated structures. To study the mechanical properties of the vertical joints in the designed prefabricated underground silo steel plate concrete composite wall and verify their reliability, flexural and compressive experiments were conducted using two groups of six full-scale steel plate concrete composite wall specimens; the mechanical properties between jointed and jointless specimens were compared and analyzed. The experimental results indicate that all specimens are in the elastic stage during the entire loading process; further, they exhibit large stiffness and high bearing capacity without damages. Thus, the designed vertical joints of the steel plate concrete composite wall provide a reliable connection that is safe and applicable. Further, the flexural and compressive properties of jointed and jointless specimens were found to be similar; the newly designed prefabricated underground silo steel plate concrete composite wall could be designed using the “equivalent principle” that the combined wall design calculation with the joint could be equivalent to that without the joint

    A meta-analysis of factors predicting parental mediation of children's media use based on studies published between 1992–2019

    No full text
    Restrictive and active parental mediation are widely used to manage child’s media use. Restrictive mediation included limiting child’s media using time/amount, or forbidden media contents. Active mediation refers to discussing media content or use method with their children. While predictors of parental mediation have been broadly studied, conflicting results have been reported. This study aims to examine the predictors of restrictive and active mediation using a meta-analysis of 32 empirical studies and 33 independent sample sets, representing over 21,000 participants. Results show that parents’ negative attitude towards media (r = 0.161) was the main predictor of restrictive mediation, while parents’ involvement (r = 0.156) was the major predictor of active mediation. Video games (r = −0.243) were found to have a stronger effect on the relationship between children’s age and restrictive mediation than any other medium. Also, adolescents (r = 0.230) have a stronger effect on the relationship between parents’ involvement and active mediation. Results further showed that compared to Asia, US (r = 0.129) and Europe (r = 0.102) have stronger effects on the relationship between parents’ negative attitude towards media and active mediation (r = −0.030). Likewise, compared to demographic variables, parents’ involvement and attitude towards media are stronger predictors of parental mediation. Further research should focus on parental mediation on new media and in cross-cultural contexts

    Effects of Soybean Isoflavone and Astragalus Polysaccharide Mixture on Colostrum Components, Serum Antioxidant, Immune and Hormone Levels of Lactating Sows

    No full text
    The objectives of this study were to investigate the effects of soybean isoflavone (SI) and astragalus polysaccharide (APS) mixture on the colostrum components, serum antioxidant, immune and hormone levels of lactating sows. A total of 72 healthy Yorkshire × Landrace lactating sows, were randomly divided into four treatments with six replicates and three lactating sows for each replicate. The control group was fed the basal diet, while the experimental groups were fed the basal diet with 100, 200 and 300 mg/kg SI and APS mixture in the form of powder, respectively. Compared with the control group, (a) the total lactation yield of the 200 mg/kg group was significantly higher (p < 0.05) at 21 days, (b) there was no significant difference in colostrum composition, (c) TG, CHO and MDA content in each treatment group were significantly decreased (p < 0.05), (d) IgA, GH, IGF-1, TNF-α and SOD contents in the 200 mg/kg group were significantly increased (p < 0.05). The SI and APS mixture could improve the average daily feed intake, lactation yield, serum antioxidant activities, immune function, and hormone levels of lactating sows, and the optimum dosage in this study was 200 mg/kg

    Characterization of spontaneously-developed non-alcoholic fatty liver disease in aged rhesus monkeys

    No full text
    Abstract Background Non-alcoholic fatty liver disease (NAFLD) is a global epidemic afflicting 20–30% in the general population. The animal model of NAFLD available at the present are less clinically relevant. In this study. We aimed to establish a NAFLD model of rhesus monkeys and develop an ultrasonographic steatosis score (USS) system to grade hepatic steatosis in this model. Methods We performed hepatic ultrasonography and blood biochemical tests on 86 rhesus monkeys with and without metabolic syndrome (MetS), among which 45 animals were further assessed by histopathological analysis. Results The liver histological features of rhesus monkeys NAFLD were resemble to those of NAFLD patients. There was a close correlation between the histological steatosis grade and the USS (Spearman’s coefficient, 0.705, p < 0.001). The USS sensitivity was 87.5% and the specificity was 94.6% when the cut-off was USS2. In addition, the prevalence of MetS was significantly higher in the USS2–3 group. Multiple risk factors of cardiometabolic disease, including obesity, insulin resistance and dyslipidemia were significantly correlated with the USS. Conclusions NAFLD was developed spontaneously among aging in rhesus monkeys (with increased prevalence in the MetS monkeys), which provided an ideal model for NAFLD. The newly developed USS system can be used to evaluate fatty liver in the rhesus monkey. The model as well as the noninvasive assessment methodology will provide a powerful tool for mechanistic studies and preclinical test of novel therapies for NAFLD
    corecore