General Information 
Student:  Yi Ming Yu () 
College:  New York City College of Technology,CUNY 
Email:  yiming.yu@mail.citytech.cuny.edu 
Research:  West Nile Disease Modeling 
Mentor: 
Dr. Nina Feffermen and Ashey NeDegre 
Project Description
Vectorborne disease surveillance programs can monitor the host, the vector, or both. Our hypothesis for this project is that surveillance that targets only the host may be underestimating the prevalence of the West Nile virus due to many mosquitoes feeding only on birds too weakened by disease to defend themselves or mosquitoes feeding more often on certian birds with certian smell. Hence, there could be may infectious mosquitoes, even though only a small portion of the bird population being monitored is infected. 
Week 1:
Meeting with all the students and graduate mentors in the Feffermen lab, we discussed potential projects and I decided to work on the West Nile Project. In order to prepare for the presentation on Friday, I searched and read articles online. Along the way I tried to get into the project I was motivated to learn biology and modeling. I searched articles about the immunity of birds, life cycle and feeding habits of mosquitos, and knowledge of WNV. I also read articles of SIR model. I was impressive by the ideas of how the models being constructed mathematically with the biological reasons. I wrote my presentation and presented it on Friday. (6/9/2011) 
Week 2:
This week I implemented the dynamical system attainted from my mentor in Mathematica and we got the expected result. However, there were two different versions of the system in the paper and in the Mathematica while I tried to understand the dynamical system.(6/15/2012) 
Week 3:
I adapted other model and implemented the spreading of WNV model, which supports our hypothesis. This also leads to a more interesting discussion involved three factors relative to the testing of our hypothesis. My mentor and I also discuss the model done by the previous REU student and we were still in progress.(6/26/2012) 
Week 4:
I have met with Dr. Nina and Ashley and clarified some of the equations from the model in the paper. I implement the model in the paper again but the result was not what I expected. Then I implement the model in the code again and correct the some of the equations, whose result was reasonable. However, there were major difference between the code in the paper and that in the code. I also modified a different model and implemented, which gave me a good result. Up to here, I felt like there were some situations needed to be address in order to interpret the results.(6/30/2012) 
Week 5:
Since we have found many problems in the code, we decided working on a new model again. Meeting with Dr. Nina and Ashley, we built the dynamical flowchart for the model in which the mosquitos would be divided into three stage of blood feeding and discussed some of the parameters. I also presented my SEIR model and its simulation results. I presented her the graphs of number of infected mosquitos and number of positive dead birds and the sensitivity of the change due to the change of attraction factor. I was suggested to plot the graph in terms of percentage of the population and the graph of the percentage change.(7/16/2012) 
Week 6:
Meeting with Dr. Nina again, which was always a cool meeting, I tried to confirmed everything single detail of the model from her. After the last meeting, I tried to work on the differential equations of the model. However, I felt that I could not go any further since I didn’t understand the parameters of the model or the parameters didn’t make sense to me. I decide to wrote the equations anyway and took the parts that made sense to me for the building of the model. After the struggle of many hours, I draw the flowchart of the parts of the equations and the “unstable” differential equations. They were “unstable “ because whenever I looked it back I found a new pointed needed to be considered and I would modify it again. Meeting with Dr. Nina was cool because she could make the “unstable” stable. At this point, I had a new model of the spread of WNV. Beside that, I worked on the PowerPoint for our final presentation at the same time I wrote my report for the program. And now I am updating my website for the pass week, current week and the next week ( keep myself on track).(7/16/2012) 
Week 7:
After a whole week of preparation, we presented our presentation on Thursday. It was a great time during the presentation. I learned what other people have done with their impressive results. As usual, I met with Ashley but we talked about graduate school instead of the project. I also kept working the final report. (7/24/2012) 
Week 8:
We have lab meeting and talked about the general thing. I kept working on my final report. (7/24/2012) 
