Coiled coil coincidence

Assume that we have a pendulum (Fig. 6-14) provided with a piece of soft iron P placed coaxially with a coil C carrying an alternating current that is, the axis of the coil coincides with the longitudinal axis OP of the pendulum at rest. If the coil is excited, one finds that the pendulum in due course begins to oscillate, and th oscillations finally reach a stationary amplitude. It is important to note that between the period of oscillation of the pendulum and the period of the alternating current there exists no rational ratio, so that the question of the subharmonic effect is ruled out. 

If linear dimensions of probe coils coincide (/ = 5, = Tt = ri) then ... 

In this paper we use the layer approximation 1 in order to compute the change in impedance of an air-core coil symmetrically located above a conducting cylinder of finite thickness d (a coin, for example). The axis of the coil coincides with the axis of the cylinder. In this case formula 1 can be written in the form ... 

Volume approximation (when the surface contribution to the free energy of a globule is neglected) works the better the farther the system is from the point of the coil-to-globule transition. In the framework of this approximation, it coincides with the -point, whereas under the theoretical consideration where the surface layer is taken into account, a gap appears separating these two points. The less is the length of polymer chain l, the more pronounced is this gap. Hence, the condition, imposed on the thermodynamic and stoichiometric parameters of the system by the equation of the -point,... 

To determine the practical effects of mosquito coils, field trials were conducted in tropical households against indoor night biting mosquitoes, particularly C. quinquefasciatus using the Human Bare-Leg technique [4], The trials were conducted from 21 00 to 01 00 the next morning, in order to coincide with the peak activity period of C. quinquefasciatus. 

The coil structures are initially positioned coincident with the positive maxima and negative minima of the MSE current density map with their initial cross sectional areas being proportional to the value of the associated current densities. The coil locations and dimensions are then... 

The IR studies of Idelson and Blout (53) demonstrated that in dioxane the initially-formed polymer possessed a random-coiled structure (described by the authors as the /3-form). As the reaction proceeded a new material appeared, which was identified through its IR spectrum as the a-helix. This stage of the process coincided with the onset of a fast reaction. By using a deuterated n-hexyl amine as the initiator a labelled /S-peptide was prepared. This was used in turn to initiate further polymerisation which yielded an a-peptide. The isolation of the latter and its analysis proved that the a-peptide contained the expected percentage of deuterium, and hence the /S-polymer had to be the precursor of a-peptide. 

Fig. 3. Conformation of the switch-2 cluster and neck linker/neck region in various members of the kinesin superfamily. The upper four panels (A, B, E, F) show crystal structures of N-type kinesins with their motor domain at the N-terminus and the neck at the C-terminus. (C), (D), (G), and (H) show C- and M-type kinesins with their neck N-terminal to the motor domain, except for PoKCBP (G) where the C-terminal neck mimic is shown instead of the N-terminal neck (which is not included in the crystal structure). Each structure is shown in two orientations that differ by a rotation of 90 degrees. Rat conventional kinesin (RnKHC [A]) has been chosen to define standard orientations with the neck helix a7 parallel/perpendicular to the drawing area. Orientations for the other structures have been determined by least-squares superposition of their P-loop regions with that of RnKHC (using 11 Ca-atoms of residues F83-T93 in RnKHC). (B), (C), and (D) show the structures of dimeric constructs with the second motor domain in pale colors. The Ned structure in (C) is 180-degree symmetric the symmetry axis is oblique to the drawing plane and coincides with the axis of the coiled-coil that is formed by the two neck helices. In the asymmetric structure of the Ned N600K mutant (D), the second motor domain (pale) is rotated by about 75 degrees around an axis perpendicular to the coiled-coil. The structures shown in (A), (B), (F), and (G) have their switch-2 cluster in permissive conformation, whereas the conformation of structures (C), (D), (E), and (H) is obstructive, as can be told by observing the slope of the extended switch-2 helix a4. Color code red, switch-2 cluster including the extended...

The first structure of a dimeric DmNcd construct (PDB code 2NCD amino acids 281-700 Sablin et al., 1998) turned out to be perfectly symmetric (by contrast to dimers of rat kinesin-1) the two molecules of a dimer are related by a crystallographic twofold axis. The symmetry axis coincides with the axis of the coiled-coil (Fig. 3C). A similar construct (PDB code 1CZ7 amino acids 295-700 Kozielski et al., 1999) crystallized in a different space group with two dimers per asymmetric unit. Although none of the dimers has a proper twofold symmetry, their conformation is not far from that. The deviation from perfect symmetry can be described by 2- and 10-degree torsions, respectively. 

For a constant polysaccharide mass, an extended (random) coil exposes more surface area than does a helix, and a single helix exposes more than a double helix. The energy content of a polymer molecule is a property of its surface area. Thus, one consequence of a coil-to-helix transition is a diminution of the macromolecular exposed surface area and energy in compliance with the law of entropy. An increase in viscosity coincides with an increase in surface, inasmuch as the resistance to motion covers a wider area. 

A diagram of the counting sensor is shown in figure 5. From the counting sensor the residue passes to radioactive waste. The counting cell contains a coiled tube of a defined volume situated in a transparent case. On either side of the sensor case are situated two photomultipliers the outputs of which are processed by coincidence electronics. Much of the noise that produces the background count arises from the electronics and the power supplies. If two photo-... 

---