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Precise synchronisation of transmitters and receivers is particularly challenging in diffusive molecular communication environments. To this end, a point-to-point molecular communication system is examined wherein the design of the transceiver offers resilience to synchronisation errors. In particular, the development of a sequential probability ratio test-based detector, which allows for additional observations in the presence of uncertainty due to mis-synchronisation at the receiver, and a modulation design which is optimised for this receiver strategy, is considered. The structure of the probability of molecules hitting a receiver within a particular time slot is exploited. An approximate maximum log-likelihood estimator for the synchronisation error is derived and the Cramér-Rao bound (CRB) computed, to show that the performance of the proposed estimator is close to the CRB at low transmission rates. The proposed receiver and modulation designs achieve strongly improved asynchronous detection performance for the same data rate as a decision feedback based receiver by a factor of 3 to 5 on average. 

Achieving precise synchronisation between transmitters and receivers is particularly challenging in diffusive molecular communication environments. To this end, pointto-point molecular communication system design is examined wherein synchronisation errors are explicitly considered. Two transceiver design questions are considered: the development of a sequential probability ratio test-based detector which allows for additional observations in the presence of uncertainty due to miss-ynchronisation at the receiver, and a modulation design which is optimised for this receiver strategy. The modulation is based on optimising an approximation for the probability of error for the detection strategy and directly exploits the structure of the probability of molecules hitting a receiver within a particular time slot. The proposed receiver and modulation designs achieve strongly improved asynchronous detection performance for the same data rate as a decision feedback based receiver by a factor of 1/2. 

Quorum sensing is a mechanism used by bacteria to coordinate the expression of certain exofactors which are more beneficial at higher cell densities. It has been argued that quorum sensing is a way for bacteria to control gene expression where some performance metric is being optimized. Herein, bacterial growth via quorum sensing is studied under the lens of optimal control theory. Under the assumption of perfect state observation, it is shown that quorum sensing is an optimal control strategy for an infinite horizon discounted reward function. 

Quorum sensing is a mechanism used by bacteria to coordinate the expression of certain exofactors which are more beneficial at higher cell densities. It has been argued that quorum sensing is a way for bacteria to control gene expression where some performance metric is being optimized. Herein, bacterial growth via quorum sensing is studied under the lens of optimal control theory. Under the assumption of perfect state observation, it is shown that quorum sensing is an optimal control strategy for an infinite horizon discounted reward function. 

Quorum sensing plays a significant role in infection, biofilm production and potentially can impact the design of microbial fuel cells in the future. Herein, a production of public-goods interpretation is employed to introduce a novel optimization-based model for bacterial quorum sensing. In this model, each bacterium cell act as a decision-maker seeking to maximize a pay-off function under the uncertainty on the concentration of the colony population. First, the design of a socially optimal strategy profile is considered, where all the cells employ the same threshold strategy. Second, the probability of not activating while the quorum is being formed is analyzed; this phenomenon is known in the literature as cheating. Lastly, preliminary results are presented that establish a connection between the new decision-making model with experimental data.