71 research outputs found
Kinematics of the swimming of Spiroplasma
\emph{Spiroplasma} swimming is studied with a simple model based on
resistive-force theory. Specifically, we consider a bacterium shaped in the
form of a helix that propagates traveling-wave distortions which flip the
handedness of the helical cell body. We treat cell length, pitch angle, kink
velocity, and distance between kinks as parameters and calculate the swimming
velocity that arises due to the distortions. We find that, for a fixed pitch
angle, scaling collapses the swimming velocity (and the swimming efficiency) to
a universal curve that depends only on the ratio of the distance between kinks
to the cell length. Simultaneously optimizing the swimming efficiency with
respect to inter-kink length and pitch angle, we find that the optimal pitch
angle is 35.5 and the optimal inter-kink length ratio is 0.338, values
in good agreement with experimental observations.Comment: 4 pages, 5 figure
Anemia and intestinal parasitic infections in primary school students in Aracaju, Sergipe, Brazil
Fatores associados à anemia em crianças e adolescentes de escolas públicas de Salvador, Bahia, Brasil
Cytldlne Cyclic (3′, 5′) Monophosphate: Cyclic Nucleotide With a Non-Characteristic Ribose Ring Conformation
Graded doped structure fabricated by vacuum spray method to improve the luminance of polymer light-emitting diodes
New hybrid encapsulation for flexible organic light-emitting devices on plastic substrates
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