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X-Machines for Agent-Based Modeling: FLAME Perspectives
is a key symptom of asthma, which occurs in the late phase of an asthma
attack, resulting in more severe airway restriction and long-lasting secondary effects. This work presented a model of eosinophilic inflammation, that occurs in lungs during an asthma attack, and the effect that
a proposed treatment (i.e. blocking the CRTH2 receptors on resident
T-cells) can have on the inflammation. The model starts with the mast
cell degranulation associated with initiation of an asthma attack, and the
subsequent release of chemicals (PGD2, IL5) from mast cells. The PGD2
stimulates tissue resident T-Cells via the CRTH2 receptor to produce a
large quantity of IL5, which has been linked to eosinophil survival. After
a few hours, eosinophils, which are produced in large quantities in the
bone marrow, flood into the tissue and are chemotactically attracted to
the lumen by Eotaxin, released from epithelial cells. When the CRTH2
receptor is blocked, the resident T-cells do not produce additional IL5,
therefore reducing the levels of IL5 within the tissue. This influences the
amount of time eosinophils are able to survive within the tissue, thereby
reducing the severity of an eosinophilic inflammation. The results are
validated against experimental data for a related anti-IL5 drug.
7.1.3 Ecological Models
Social insects: foraging in ants. Communication improves decision- making for group-living animals, especially during foraging, facilitating exploitation of resources. Here a model was created of the trail-based foraging strategy of Pharaoh’s ants to understand the limits and constraints of
a specific group foraging strategy. To minimize assumptions, the model
parameters acquired through behavioral study were used. Pharaoh’s ants
(Monomorium pharaonis) exploit the geometry of trail network bifurcations to make U-turns if they are walking the wrong way. However,
7% of foragers perform apparently incorrect U-turns. These seemingly
maladaptive U-turns are performed by a consistent minority of specialist
U-turners that make frequent U-turns on trails and lay trail pheromones
much more frequently compared to the rest of the colony. The study
showed a key role for U-turning ants in maintaining the connectivity
of pheromone trails. The authors produced an agent-based model of a
heterogeneous ant community where 7% of agents were specialized frequent U-turners whilst the remaining 93% rarely U-turned. Simulations
showed that heterogeneous colonies enjoyed significantly greater success
at foraging for distant food resources compared to behaviorally homogeneous colonies. The presence of a cohort of specialized trail-layers maintained a well-connected network of trails that ensured that food discoveries are rapidly linked back to the nest. This decentralized information
transfer might ensure that foragers can respond to dynamic changes in
X-Machines for Agent-Based Modeling: FLAME Perspectives
is a key symptom of asthma, which occurs in the late phase of an asthma
attack, resulting in more severe airway restriction and long-lasting secondary effects. This work presented a model of eosinophilic inflammation, that occurs in lungs during an asthma attack, and the effect that
a proposed treatment (i.e. blocking the CRTH2 receptors on resident
T-cells) can have on the inflammation. The model starts with the mast
cell degranulation associated with initiation of an asthma attack, and the
subsequent release of chemicals (PGD2, IL5) from mast cells. The PGD2
stimulates tissue resident T-Cells via the CRTH2 receptor to produce a
large quantity of IL5, which has been linked to eosinophil survival. After
a few hours, eosinophils, which are produced in large quantities in the
bone marrow, flood into the tissue and are chemotactically attracted to
the lumen by Eotaxin, released from epithelial cells. When the CRTH2
receptor is blocked, the resident T-cells do not produce additional IL5,
therefore reducing the levels of IL5 within the tissue. This influences the
amount of time eosinophils are able to survive within the tissue, thereby
reducing the severity of an eosinophilic inflammation. The results are
validated against experimental data for a related anti-IL5 drug.
7.1.3 Ecological Models
Social insects: foraging in ants. Communication improves decision- making for group-living animals, especially during foraging, facilitating exploitation of resources. Here a model was created of the trail-based foraging strategy of Pharaoh’s ants to understand the limits and constraints of
a specific group foraging strategy. To minimize assumptions, the model
parameters acquired through behavioral study were used. Pharaoh’s ants
(Monomorium pharaonis) exploit the geometry of trail network bifurcations to make U-turns if they are walking the wrong way. However,
7% of foragers perform apparently incorrect U-turns. These seemingly
maladaptive U-turns are performed by a consistent minority of specialist
U-turners that make frequent U-turns on trails and lay trail pheromones
much more frequently compared to the rest of the colony. The study
showed a key role for U-turning ants in maintaining the connectivity
of pheromone trails. The authors produced an agent-based model of a
heterogeneous ant community where 7% of agents were specialized frequent U-turners whilst the remaining 93% rarely U-turned. Simulations
showed that heterogeneous colonies enjoyed significantly greater success
at foraging for distant food resources compared to behaviorally homogeneous colonies. The presence of a cohort of specialized trail-layers maintained a well-connected network of trails that ensured that food discoveries are rapidly linked back to the nest. This decentralized information
transfer might ensure that foragers can respond to dynamic changes in