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Colorectal Cancer (CRC) is becoming a major threat to people’s life in China. Screening methods adopted by many other countries as effective counter-cancer methods have not been explicitly explored for people there. Thus, we present a Markov model with detailed precancerous adenoma states and then evaluate various screening strategies in this paper. Different from current researches, our model considers the population’s heterogeneous risk of developing adenomas and observation-based screening strategies. Furthermore, we also give a new cost-effectiveness metric. After calibrating, the model is simulated using the Monte Carlo method. Numerical results show that there are threshold values of compliance rates below which strategy with every ten-year colonoscopy becomes the most cost-effective method; otherwise, an observation-based screening strategy is the most cost-effective. We also find that strategy with single colonoscopy for adenoma-free individuals and every three-year colonoscopy for those with adenoma is recommended when the observation-based strategy is not considered. Our findings give an explicit and complete instruction in CRC screening protocol in average-risk Chinese. [ABSTRACT FROM AUTHOR]

In the digital innovation ecosystem, the symbiosis mode formed between ecosystem members not only relates to their survival and development but also affects the ecosystem's symbiosis evolution mechanism. Based on symbiosis theory, this study first explores the evolutionary equilibrium strategy and its stability for three types of populations—core enterprises, digital platforms, and university research institutes—and then uses numerical simulation and a case study to explore the symbiotic evolution mechanism of the digital innovation ecosystem. The results show that: First, the digital innovation ecosystem is a complex adaptive system in which the three types of populations form different symbiotic relationships under different symbiotic modes and conduct symbiotic activities, such as value co-creation, to characterize the unique symbiotic evolutionary structure. Second, in this ecosystem, the symbiotic relationship formed by the combined values of different symbiotic coefficients between populations determines the outcome of symbiotic evolution. Third, the ideal direction of the evolution of the digital innovation ecosystem is a mutually beneficial symbiotic relationship. Thus, the symbiotic relationship between populations should be transformed into a mutually beneficial symbiotic relationships as much as possible. This study makes theoretical contributions by shedding light on the symbiotic evolution mechanism of the digital innovation ecosystem. It also offers countermeasures for the digital innovation cooperation of various stakeholders in China's digital innovation ecosystem. [ABSTRACT FROM AUTHOR]

Hepatitis B is an infectious disease caused by the hepatitis B virus (HBV) which affects livers. In this paper, we formulate a hepatitis B model to study the transmission dynamics of hepatitis B in Xinjiang, China. The epidemic model involves an exponential birth rate and vertical transmission. For a better understanding of HBV transmission dynamics, we analyze the dynamic behavior of the model. The modified reproductive number σ is obtained. When σ < 1, the disease-free equilibrium is locally asymptotically stable, when σ > 1, the disease-free equilibrium is unstable and the disease is uniformly persistent. In the simulation, parameters are chosen to fit public data in Xinjiang. The simulation indicates that the cumulated HBV infection number in Xinjiang will attain about 600,000 cases unless there are stronger or more effective control measures by the end of 2017. Sensitive analysis results show that enhancing the vaccination rate for newborns in Xinjiang is very effective to stop the transmission of HBV. Hence, we recommend that all infants in Xinjiang receive the hepatitis B vaccine as soon as possible after birth.

In recent years, NIMBY(Not In My Backyard) conflicts gradually become hot and difficult in the international community governance, people have realized that the government and people on both sides of the emotional factors have great influences on the results of the conflicts, especially to study the effects of emotion on the evolution of conflicts in China, this article from the following several aspects. First of all, a game model under the influences of emotion is constructed by using Range Dependent Expected Utility(RDEU) theory and emotional function. Secondly, the Jacobian matrix is utilized to analyze the stability of the equilibrium point for the model constructed above. Next, numerical simulation is used to analyze the evolution trend of discrete emotions. The evolutionary results show that when one party holds an optimistic mood, equilibrium evolves to a relatively optimal state; while when one party holds a pessimistic mood, the more pessimistic the party is, the more likely it is to cause NIMBY conflicts. Compared with the people's sentiments, the government's moods have a greater impact on the evolutionary consequences. Finally, depending on the conclusions of the evolutionary analysis, some suggestions on the governance of NIMBY conflicts are put forward. [ABSTRACT FROM AUTHOR]

To investigate the cutting forces on road-header picks, a series of full-scale single-pick rotary cutting tests on sandstone samples were conducted at the National Engineering Laboratory of Coal Mining Machinery and Equipment, China. The primary objective of this study is to optimize the cut spacing and to verify the numerical simulation results. Cutting forces are investigated under different cutting depths and cut spacings. Cut spacing is optimized by analyzing the specific energy, coarseness index, and cutting force. The rock cutting process is simulated on a pick model using the PFC3D software. Rock samples are used as models, and particle assemblies and micro-properties are calibrated by uniaxial compressive strength tests and Brazilian disc tensile strength tests. The optimum ratio of cut spacing to cutting depth for the analyzed sandstone is determined to be in the range of 3 to 4. The experimental results show that a higher coarseness index corresponds to an increased block ratio, and specific energy decreases under optimum cutting conditions. Forces acting on the pick model are determined by simulation. A reasonable agreement exists between the experimental and numerical simulation results regarding the pick forces. The influence of the cut spacing on the rock-breaking effect observed in the experiments is confirmed by numerical simulations. Therefore, numerical simulations using the PFC3D software represent a reliable method for predicting the pick forces. [ABSTRACT FROM AUTHOR]

The interaction of active faults as a factor affecting the mechanisms of large earthquakes has been observed in many places. Most aftershock and clustering earthquake sequences do not recur on the main seismogenic fault but are controlled by fault interactions with adjacent seismic structures. Four groups of conceptual models were generated in this study to determine how the geometry of the seismogenic faults controls the distributions of stress fields and earthquakes. The influences of the fault length ratio, center distance, overlap ratio, echelon distance and fault opening angle were considered in a 2D viscoelastic model. The results indicate that the interaction in the slipping zone is larger when collinear interacting faults are more closely positioned, with one fault lengthening. For noncollinear faults, the interaction is stronger as the inner tips pass each other, which impedes their growth after some degree of overlap. Additionally, fault interaction at the slipping zone becomes stronger as the opening angle approaches 180°. We further generated a 3D viscoelastic model of fault interactions in Central North China Block and applied the finite element method to analyze the relationship between distributions of earthquakes and fault geometry. The calculated results reveal well-matched higher stress and maximum shear strain concentrations in the southern part of the Fen-wei Graben Zone than in other zones in Central North China Block, which can be explained by the longer faults, shorter center distances, shorter overlap lengths and larger opening angles. The stress distributions and fault interactions should be considered in long-term seismic hazard assessment in these zones. [ABSTRACT FROM AUTHOR]

We investigated the inter-day effects of price limits policies that are employed in agent-based simulations. To isolate the impact of price limits from the impact of other factors, we built an artificial stock market with higher frequency price limits hitting. The trading mechanisms in this market are the same as the trading mechanisms in China’s stock market. Then, we designed a series of simulations with and without price limits policy. The results of these simulations demonstrate that both upper and lower price limits can cause a volatility spillover effect and a trading interference effect. The process of price discovery will be delayed if upper price limits are imposed on a stock market; however, this phenomenon does not occur when lower price limits are imposed. [ABSTRACT FROM AUTHOR]

Objective: The objectives of this study were to forecast epidemic peaks of typhoid and paratyphoid fever in China using the grey disaster model, to evaluate its feasibility of predicting the epidemic tendency of notifiable diseases. Methods: According to epidemiological features, the GM(1,1) model and DGM model were used to build the grey disaster model based on the incidence data of typhoid and paratyphoid fever collected from the China Health Statistical Yearbook. Model fitting accuracy test was used to evaluate the performance of these two models. Then, the next catastrophe date was predicted by the better model. Results: The simulation results showed that DGM model was better than GM(1,1) model in our data set. Using the DGM model, we predicted the next epidemic peak time will occur between 2023 to 2025. Conclusion: The grey disaster model can predict the typhoid and paratyphoid fever epidemic time precisely, which may provide valuable information for disease prevention and control. [ABSTRACT FROM AUTHOR]