The chemotactic dynamics of cells URLanisms that have no specialized gradient URLanelles is not well understood. In fact, chemotaxis of this sort URLanism is especially challenging to explain when the external chemical gradient is so small as to make variations of concentrations minute over the length of each of URLanisms. Experimental evidence lends support to the conjecture that chemotactic behavior of chains of cells can be achieved via cell-to-cell communication. This is the chemotactic basis for the  Local Excitation, Global Inhibition (LEGI) model. A generalization of the model for the communication component of the LEGI model is proposed. Doing so permits us to study in detail how gradient sensing changes as a function of the structure of the communication term. The key findings of this study are, an accounting of how gradient sensing is affected by the competition of communication and diffusive processes; the determination of the scale dependence of the model outcomes; the sensitivity of communicationto parameters in the model. Together with an essential analysis of the dynamics of the model, these findings can prove useful in suggesting experiments aimed at determining the viability of a communication mechanism in chemotactic dynamics of chains and networks of cells exposed to a chemical concentration gradient .
 Experimental evidence lends support to the conjecture that the ability of chains of cells to sense the gradient of an external chemical concentration could rely on cell-to-cell communication. This is the basis for the gradient sensing nature of a specific model type of the Local Excitation, Global Inhibition (LEGI) principle, wherein the strength of the external chemical field is sensed through a comparison between a local exciting species and a global inhibitor that is shared via intra-cellular reactions in the cell chain. In this study we generalize the nearest neighbor communication mechanism in the above-mentioned LEGI model in order to explore how the chemical sensing characteristics depend on the parameterization of the communication itself, cell size, and the radius of influence of neighboring cells. It was found that the radius of influence was less important than the approximating model for communication. Higher order approximations to the communication mechanism were better able to sense an external gradient. However, an analysis of the signal to noise ratio established that higher order models for communication were more prone to noise and thus have a lower signal to noise ratio. The generalization as well as the tools used in the analysis of the dynamics can be extended to more heterogeneous networks and can thus prove useful in using models and observations in the process of understanding chemical gradient via LEGI models with a communication component .
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The chemotactic dynamics of cells URLanisms that have no specialized gradient URLanelles is not well understood. In fact, chemotaxis of this sort URLanism is especially challenging to explain when the external chemical gradient is so small as to make variations of concentrations minute over the length of each of URLanisms.
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chemotactic behavior
the ability
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to sense the gradient of an external chemical concentration could rely on
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chemotactic
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gradient sensing nature of a specific model type of the
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model. A generalization of the model for the communication component of the LEGI model is proposed. Doing so permits us to study in detail how gradient sensing changes as a function of the structure
principle, wherein the strength of the external chemical field is sensed through a comparison between a local exciting species and a global inhibitor that is shared via intra-cellular reactions in the cell chain. In this study we generalize the nearest neighbor communication mechanism in the above-mentioned LEGI model in order to explore how the chemical sensing characteristics depend on the parameterization
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term. The key findings of this study are, an accounting of how gradient sensing is affected by the competition of communication and diffusive processes; the determination of
itself, cell size, and
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scale dependence of
radius of influence of neighboring cells. It was found that the radius of influence was less important than the approximating model for communication. Higher order approximations to
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model outcomes; the sensitivity of communicationto parameters in the model. Together with an essential
communication mechanism were better able to sense an external gradient. However, an
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dynamics of the model, these findings can
signal to noise ratio established that higher order models for communication were more prone to noise and thus have a lower signal to noise ratio. The generalization as well as the tools used in the analysis of the dynamics can be extended to more heterogeneous networks and can thus
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suggesting experiments aimed at determining the viability of a communication mechanism in chemotactic dynamics of chains and networks of cells exposed to a chemical concentration gradient
using models and observations in the process of understanding chemical gradient via LEGI models with a communication component