Team:TPR China/Implementation

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Implementation

Overview

In our mission to create a solution to eliminate the locust plague. We designed a rapidly deployable locust attraction scheme, the core of which is to synthesis specific locust aggregation pheromone 4-Vinylanisole to attract locusts and prepare for further rapid and effective eradication in the attraction area. Furthermore, an engineered bacteria which can degrade phenylacetonitrile was successfully created, avoiding its interference to the trapping effect. Through synthesis of 4-Vinylanisole and degradation of Phenylacetonitrile, locusts are “attracted” together and the site-specific control of locust swarms is realized.

First utilization: a community device

From previous sources, we already know how serious is the locust plague. In order to solve the problem, we need proper designs to implement the panacea that our group had designed.
The equipment we developed with the CAU is basically a trap that is surrounded by net. At the bottom of the equipment, there is a "bait box" that could hold the 4VA and Nitrilase engineered bacteria to attract locusts and dissolve PAN. Once the locust has been attracted to the equipment, the bacteria designed by the team CAU will kill those locusts.

How to apply it in real-life situation?

If there's locusts present in the community, first, report to the community manager about the situation, with specific information about the location and the number of locust present. Secondly, the community manager warning the residents to stay away from the reported area and take the trapping device we designed with them to the reported area to check whether the situation is true or not. If it's false, the alarm will be cancelled. If it's present, the community manager will clear the area first. Then, open the trapping device, follow the instructions written on the packaging, and put the engineered bacterium (which is usually locked up in the manager's office) into the tools. After setting up the device, now is the time to find the most appropriate place for placing it. By looking at the locust travelling direction, height from the ground, speed of travelling, etc., put the trapping device on the travelling path, some position in the air. After setting up, the community manager steps out of the area, wait for 6 hours, allowing the locust to be a trap into the device and decompose most of the PAN concentration in air. Just in case there's still lots of PAN in the air, the manager should wear a gas mask to check the area. Afterwards, the locusts will be placed in the trapping device and have a low concentration of PAN, which won't harm the environment, as the device is used in the community rarely, the manager could simply kill the locusts or waiting for technical support from experts to deal with the locust professionally as community manager might not be capable of further professional techniques to deal with the locusts.
Since the scenario mentioned previously are mostly focus on community problems, so for the community type of trap device, we could make a small equipment supplier, which can handle selling, installing, repairing, teaching etc. By having advisors who can guide different communities' managers, the following procedure, and once the storage is used up could ask for more. Even help to repair it and install it by giving all the needs for using the trap device correctly and can be shared between each family. The device is able to serve as consumer goods throughout the market as it will be beginner's friendly.

Who are the customers?

Moreover, the customer group that we are considering facing in the future will be two types:
One is the scattered farmers who need precaution to take care of their own crops. The others will be agriculture offices near the suburban area, and the frequent locust's plague occurs areas. For recurring locust plague occur regions, we recommend putting the trapping device on all year long, when the swarms of locusts invade, just simply add on our bacterium into the trapping device, which will help to save some time. Usually, families who live in urban areas don't need to purchase our product as locust plague is very unlikely to occur in cities, and it will go off by itself as there's no food to feed the locusts.
Nevertheless, as we mentioned earlier, in general, the trap device is hanged vertically in the community, we will use signs to warning the public to not move or touch the device. However, kids can be interested in the device and touch it without parents notice. The device also might trap quite a significant number of locusts, which will also arouse children's curiosity, and might cause the risk of being harmed by venomous insects. So firstly, the devices are suggested to place at places that children are hard to reach, and warning residents before hanging up the device, and keep the area clear with a label around, avoiding any residents near the device while functioning.

Further Steps to Take

Lastly, as the 4VA engineered bacterium we produced haven't been tested on any other insect attraction ability, so before putting it out in the market, we still need further testing and observation of the attractive or toxic ability to different kinds of insects and other animals to make sure there's no additional risk by using our product.

Second utilization: a Bigger Scale of Problem Solving

Beside of the equipment we build with CAU_China, we also came up with a model that shows the functioning area of the 4VA and Nitrilase that has been produced by bacteria in order to encounter large scale locust plague. With this "pit" shaped model, we could have a pretty good idea of where we should put our engineered bacteria and thus let it play its role.

Importance

Firstly, it is important to stress that this pit is only used for emergency response facility for large-scale locust outbreaks, that’s similar to those in East Africa and Bagistan earlier this year.
And due to the size of the locust swarm, it is impossible to eliminate it by community device, so this will involve in various equipment. And even with the community to purchase this pit device, it is still a problem to solve this locust plague, since it’s not only involving in the equipment, but also experts, and human resources such as the place to put our engineer bacterium, use of excavators, satellite, etc.. So, the problem now is not only for a community or a farmer, is more about everyone’s problem in the area, so the regional or country agriculture department should step in to solve the problem together.
So after the large-scale locust outbreaks begin, we can monitor the movement of the locust by satellite, to know the exact size of the locust plague and by experts prediction of locusts swarms moving path and the size of the swarm, we can allocate a place to set up our device, which will always be in front of most of the crops and the size of the pit we create will mainly depend on the radius of the locust swarms. Since the locust’s swarms will be huge, so we have to use the excavator to dig the hole more efficiently. And the place expert selected to intercept the swarm of locust probably will be some private land, and the negotiations will have to let the official department to step in. And by doing such large amount of elimination, the bacterium we have used for community use will not be enough, so the lab will have to produce more or use all its storage for this elimination plan, and the use of such large amount of bacterium should be guided or directly employed by scientists.
Moreover, the device we create can only attract the locusts and helps to decompose the PAN concentration, we can’t kill them. So we need to use another product to help with the last part. You may think if we can’t finish the killing part, how can our device be useful. But by using our bacterium, we can efficiently decrease the amount of cost to attract locusts, and by decomposing the PAN concentration, the locusts won’t release as much as a volatile component to the environment as usual. So our method had also given consideration to the compatibility of the current industrial chain and social care.

Reflection: Problems to Tackle

However, these two methods both possesses some obvious problems:
Firstly, the accuracy of our estimation for our second utilization. If the prediction was wrong, the hole will be useless and the cost will be wasted, which is unworthy. So our team had made an attractive field model to predict the place to put our product, which illustrate the relationship between the concentration of 4VA and attractive factor to the initial diffusion model. By the attractive factor, we then create an attractive pit which shows the area that locusts are more attractive than others.
Secondly, both utilization 1 and 2 face this problem. Since PAN is an harmful product to the environment, by gathering large scale of gregarious locusts, it will also gather an enormous amount of PAN in the area. Also, PAN itself is serve as an compelling pheromone which could curtain the attraction ability of our attractive pit. By comparing the effective attraction area before and after PAN added, we could say that the attractive field gets less effective, leading to approximately 3/4 attractibility compared to the initial status. So the problem caused by the concentration of PAN can extremely devastate our goals.
Before PAN Added After PAN added
Effective attraction area (㎡) 1608000 1211500
Luckily, we had first designed engineered bacteria to dissolve the PAN concentration which could help to protect the environment while solving locust plague. Moreover, we had considered the possibility of decompose high PAN concentration after gathering it in our model. And by adding our engineering strains to decompose PAN, we could maintain the attractive ability in a high level rather than decrease to one half of attractiveness while maintaining a high level of PAN concentration in the environment.
Another challenge we will face is the cost of our utilization 2. As locust plague is a worldwide problem, and the FAO launched a 76 million dollars preparatory appeal which could show how locust plague needs a large amount of money to solve it. However, most labour doesn't have a large amount of money, still need to protect their only profit—— the food they grow. So our team had also taken the economic problem into account, and made an economic model to predict the total cost and the impact of the locust plague on the total income. By using the LASSO regression principle, the L1 regularization, the logistic regression and the Gradient descent method to get this result.
fitting function for profit prediction

Although this is just a prediction based on the data we obtained from the experiment, the profit we calculated is about 315 million RMB(approximately 47 million dollars), which has a positive profit. Although this is just our prediction based on the data from the experiment, we believe our project could bring benefits!

Safety

Nonetheless, there are some safety problems. When there is a large scale aggregation of locusts, it would produce an enormous amount of PAN which would be harmful to the environment. Luckily, we already had the the engineered bacteria that could dissolve the PAN in the surrounding area.