Ferrel cells

The motions on the largest spatial scales amount to the aggregate of the world s synoptic weather systems, often called the general circulation. Both with respect to substances that have atmospheric lifetimes of a day or more and with regard to the advection of water, it is useful to depict the nature of this general circulation. The mean circulation is described to some extent in terms of the Hadley and Ferrell cells shown in Fig. 7-4. They describe a coupled circulation... 

The descending branch of the Hadley cell gives rise to a high-pressure belt at about 30° latitude. Further poleward, the meridional circulation is opposite in direction to that required for thermally driven motion. These features, which are called Ferrel cells, must be indirect circulation systems. Yet another pair of cells is evident in the polar regions. They are very weak systems. 

Air circulation in the troposphere convection cells. 1) Hadley CeU, 2) Ferrel Cell, 3) Polar CeU. 

Air circulates within the troposphere from the equator toward the two poles. In simple terms, the hot air at the equator rises and moves toward the poles when it encounters cold temperatures at the poles, it becomes more dense and sinks, then circulates back toward the equator. In fact, this occurs in a series of convection cells that run from the equator to each pole as shown in Figure 2.3 (adapted from [58]). The Hadley cells are locateid at the equator. Air circulates in the Hadley cells toward each of the poles, to a latitude of approximately 30° N/S. North and south of the Hadley cells lie the Ferrel cells. Air circulates between approximately 30° and 60° in the Ferrel cells. Near the surface of the earth, the air flows toward the pole and eastward high in the troposphere the air circulates back toward the equator and toward the west. Beyond the Ferrel cells are the Polar cells. Air circulates within these cells between approximately 60° N and the North Pole, blowing in an easterly direction, or between 60° S and the South Pole [59]. 

Ferrel, J. E. Jr., Wo, M., Gerhaart, J. C., and Martin, G. S. (1991). Cell cycle tyrosine phosphorylation of p34c 2 and a microtubule-associated protein kinase homolog in Xenopus oocytes and eggs. Mol. Cell. Biol. 11 1965-1971. 

Serber Z, Selenko P, Hansel R, Reckel S, Lohr F, Ferrell JE, Wagner G, Dotsch V (2006) Investigating macromolecules inside cultured and injected cells by in-cell NMR spectroscopy. Nat Protoc 1 2701-2709... 

Ferrel, J., Kotar, A. and Stern, S. (1996). Direct Hydrogen Fuelled Proton Exchange Membrane (PEM) Fuel Cell System for Transportation Applications. Final report, Section 3 Hydrogen Infrastructure Report. Prepared for the Ford Motor Company and the Department of Energy. 

J. E. Ferrell, Jr., and W. Xiong, Bistability in cell signaling How to make continuous processes discontinuous, and reversible processes irreversible. Chaos 11(1), 227 236 (2001). 

Ferrell, J. E., Jr., and Machleder, E. M. (1998). The biochemical basis of an all-or-none cell fate switch in Xenopus oocytes. Science 280,895-8. 

Because of the rotation of the Earth and because of the warm equatorial and cool polar regions, the atmosphere divides itself into six regions (roughly corresponding to the climatic zones). These atmospheric regions are called the northern and southern Polar, Ferrel, and Hadley cells (so called because they are roll cells ) see Figure 3.2. This division of the atmosphere tends to slow the mixing... 

An attempt was made recently to find out how sensitively the regulatory system that controls the cell cycle and cell proliferation responds to signal input. Ferrell et found that, in intact oocytes, the response is ultrasensitive , a kinetic characterization introduced by Daniel E. Koshland Jr.26 (Ultrasensitivity has been defined as the response of an enzyme that is more sensitive to changes in the concentration of the substrate than an enzyme with a normal hyperbolic response, according to the Michaelis-Menten equation. One can also use the Hill coefficient (wh) to indicate hyperbolic (Michaelis-Menten) sensitivity ( h = 1-0), ultrasensitivity ( h > l)j and subsensitivity ( h <... 

C. Y. Huang and J. E. Fendl Jr. Ultrasensitivity in the mitogen-activated protein kinase cascade. Proc Natl Acad Sd USA 93 (19), 10078-10083, 1996. Also J. E. Ferrell Jr and E. M. Machleder. The biochemical basis of an all-or-none cell fate switch in Xetmpus oocytes [see comments]. Science, 280 (5365), 895-898, 1998. 

Pomerening JR, Sontag ED, Ferrell Jr JE. Building a cell cycle oscillator hysteresis and bistability in the activation of Cdc2. Nat. Cell Biol. 2003 5 346-351. 

J.E. Ferrell (r, Self-perpetuating states in signal transduction positive feedback, double-negative feedback and bistability, Curr. Opin. Cell Biol. 2002, 14,140-148. 

Walter SA, Guadagno SN, Ferrell JE, Jr. 2000. Activation of Weel by p>42 MAPK in vitro and in cycling xenopus egg extracts. Mol Biol Cell ll(3) 887-896. 

Ferrell JE, Machleder EM (1998) The Biochemical Basis of an All-or-None Cell Fate Switch in Xenr s Oocytes. Science... 

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