Team:Tsinghua-A/Project/Design

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Tsinghua-A::Project::Design

What is ‘programmable‘?

Logic, which tends to be presented in the form of truth tables, shows a relationship between inputs and outputs. Below are the truth tables of the two basic gates: the And gate and the Or gate. So we quickly find the difference lies in the outputs when only one of the inputs is true. In the And gate if there are only one true input, either A or B, the output is false. But in the Or gate it’s to the contrary. So if we can control the output when only one input is true, we can successfully make the switch between the And gate and the Or gate, which can be called a programmable device.

How we make it happen?

Without loss of generality, we decide to start our project with the conversion of the two basic gates mentioned above: the And gate and the Or gate. And when it comes to the situation with 2 inputs, we construct our design like this.
Between the LoxP site there’re promoter A&B. Initially promoter A can only induce signal X, and promoter B signal Y. The Output is under the regulation which can only be induced by X AND Y.So only when both promoter A&B are activated can we get the expression of the Output. Definitely it serves as an And gate.
In response to the external stimulus we’ve given, the Cre recombinase come out and start the flip. After the flip either promoter A or promoter B can activate the expression of both signal X and signal Y. Then we can get the Output. So the system works as an Or gate. That’s how we construct the switch between the And gate and the Or gate.

What we exactly want and how?

Without loss of generality, we decide to start our project with the conversion of the two basic gates mentioned above: the And gate and the Or gate. And when it comes to the situation with 2 inputs, we construct our design like this.
Between the LoxP site there’re promoter A&B. Initially promoter A can only induce signal X, and promoter B signal Y. The Output is under the regulation which can only be induced by X AND Y.So only when both promoter A&B are activated can we get the expression of the Output. Definitely it serves as an And gate.
In response to the external stimulus we’ve given, the Cre recombinase come out and start the flip. After the flip either promoter A or promoter B can activate the expression of both signal X and signal Y. Then we can get the Output. So the system works as an Or gate. That’s how we construct the switch between the And gate and the Or gate.

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