Migration of Gyrotactic Micro-Organisms in Water

The growth of bioconvection patterns in a uniform suspension of gyrotactic micro-organisms.

'Bioconvection' is the name given to pattern-forming convective motions set up in suspensions of swimming micro-organisms. 'Gyrotaxis' describes the way the swimming is guided through a balance between the physical torques generated by viscous drag and by gravity operating on an asymmetric distribution of mass within the organism. When the organisms are heavier towards the rear, gyrotaxis turns...

Taylor dispersion of gyrotactic swimming micro-organisms in a linear flow

The theory of generalized Taylor dispersion for suspensions of Brownian particles is developed to study the dispersion of gyrotactic swimming micro-organisms in a linear shear flow. Such creatures are bottom-heavy and experience a gravitational torque which acts to right them when they are tipped away from the vertical. They also suffer a net viscous torque in the presence of a local vorticity ...

Non linear bioconvection in a deep suspension of gyrotactic swimming micro organisms

The non-linear structure of deep, stochastic, gyrotactic bioconvection is explored. A linear analysis is reviewed and a weakly non-linear analysis justifies its application by revealing the supercritical nature of the bifurcation. An asymptotic expansion is used to derive systems of partial differential equations for long plume structures which vary slowly with depth. Steady state and travellin...

Micro-Organisms in Water—Their Signification, Identification and Removal

Adaptation in Micro-Organisms

all the humdrum of mental undressing, dressing, shaving, etc., there is the chance reward of being confidential ear to what may never be so well expressed or thought of again. The contributors of the "relatively brief" presentations are six in number. Alex Bavelas talks on "Communication patterns in problem-solving groups"; Ivor A. Richards, on "Communication between men: Meaning and language";...