Ebola virus is a potent infectious disease virus that can cause Ebola haemorrhagic fever caused by human and primate. It has high mortality and easy infectivity to form a great obstacle to the steady development of human society. The profound understanding of the virus is particularly important harm. In this paper, a number of mathematical models are established to solve this problem. The software is used to analyze and predict the propagation of Ebola virus. The residual analysis is used to test the model. Finally, the effects of various control measures on controlling the epidemic are analyzed. In order to solve the problem, we will establish the infectious disease model to dynamically describe the spread of the virus in the 'virtual orangutan population'. Considering that the latent population is analyzed in this question, we will improve the model. Join the latent group (), and the migrants are divided into self-healing () and the dead (), to establish a suitable solution to this problem model. According to the relevant data given in the title, differential equations were established. For the second question, this question involves the one-way transmission of the virus across the species, so we can improve the model, on the basis of human contact with orangutans infected groups, the establishment of a one-way model to solve this problem. On the basis of the problem one, the differential equation is established, the model is predicted and tested. In the case of question 3, the number of human susceptible groups is much higher than that of the orangutan infection group by comparing the relevant data with the increase of the cure rate to 80% after the intervention of the outside experts. Therefore, the original data of human populations from experts can be ignored. Since then the virus spreads within a single species, the differential equation can be established according to the model in question 1 and the data values in the virtual human population are predicted. For question 4, the effect of the measures such as the strict enforcement of the various epidemic control measures and the improvement of the drug effect on the control of the epidemic are analyzed by comparing the above-mentioned models with the control measures.

Objective: To evaluate the ponticulus posticus according to the skeletal relationship found in strict lateral radiographs at the Centro Dental Docente of the Universidad Peruana Cayetano Heredia during the period 2015–2017, using the classification according to the degree of mineralization described by Selby and Steiner’s skeletal relationship classification. Material and methods: It was performed on digital strict lateral radiographs using a 20-inch screen using the SIDEXIS XG program, observing the degree of mineralization of the ponticulus posticus: without evidence of the bony spicule over the vertebral artery = absent bridge, when spicule formation and/or calcification was noted or evident in the middle of the bridge or incompletely = partial bridge, when the bony arch was evident finished visualizing = complete bridge and the classification of the skeletal relationship by measuring the ANB angle: Class I = 0–4°; Class II = >4° and Class III = <0°: the statistical analysis was done with the SPSS V program.22.0 for Windows using the Chi-square tests. Results: Of the 925 digital strict lateral radiographs evaluated, 283 radiographs were found to present ponticulus posticus and the highest frequency was found in the absent type (69.4%), the partial type (17.1%) and the complete type (13.5%). The ponticulus posticus was present in 25.1% of the female and 38.4% of the male. The skeletal relationship associated with ponticulus posticus was present in Class II (19.1%), Class I (10.4%) and Class III (1.1%). Conclusions: The ponticulus posticus is an anatomical variant present in 30.6% of cases. No statistically significant difference was found between the presence of ponticulus posticus and skeletal relationship or sex.

The possibility of preoperative prediction of pathologic complete response in rectal cancer has been studied in order to identify patients who would respond to neoadjuvant therapy and to individualize therapeutic strategies. Endoscopic ultrasound of the rectum is an accurate method for the evaluation of local tumor and lymph node invasion. Objective: To evaluate the potential of endoscopic ultrasound as a predictor of complete pathological response to neoadjuvant treatment in patients with locally advanced rectal cancer. Material and methods: Retrospective study of patients with rectal cancer from January 2014 to December 2016. Results: We obtained a statistical association between T stage by endoscopic ultrasound and complete pathological response (p = 0.015). It is not so for N, sphincter involvement, circumferential involvement and maximum tumor thickness (p = 0.723, p = 0.510, p = 0.233 and p = 0.114, respectively). When multivariate logistic regression analysis was applied to assess the degree of influence of the predictor variables on pathologic response, none of these variables was associated with complete pathologic response. Conclusion: Prediction of pathologic complete response in rectal cancer has been considered as the crucial point upon which treatments for rectal cancer could be individualized. So far, no imaging method has been able to demonstrate efficacy in predicting complete pathologic response, and in turn there is no direct association between any endosonographic finding that can accurately predict it.