In Memory of Professor Alex Silberberg 1923-1993 / Ephraim Katchalski-Katzir -- I. Dynein Regulation. 1. Molecular Biology of Axonemal Dynein and Its Role in Ciliary Motility / I.R. Gibbons. 2. Modeling Outer Dynein Arm Activity and Its Relation to the Ciliary Beat Cycle / Peter Satir, Toshikazu Hamasaki and Michael Holwill -- II. Ciliary Regulation. 3. Regulation of Outer Arm Dynein Activity via Light Chain Phosphorylation / Toshikazu Hamasaki, Jason H. Nielson and Peter Satir. 4. Inhibitory and Excitatory Neural Regulation of the Mucociliary Transport System / Donovan B. Yeates