Bone hook

All bone-active BPs possess the P-C-P structure, which is the basis of the structural analogy to pyrophosphates (see Fig. 15.1). This P-C-P moiety has been called the bone hook , namely it is the primary structural feature that endows the molecule its affinity and targets it to the bone. Molecules in which the two phosphonic functions are farther apart are biologically mostly inactive, although there are reports of some long-chain bisacylphosphonates having calcium-related biological activity [14]. 

PCP bone hook provides affinity to the hydroxyapatite in bone... 

Threatened or wounded sea cucumber Holothuraided) will contract its body exposing the small skeletal bones that make up the body wall, which can act as hooks to the mouths of predators. For most species, the connective tissue that makes up the greater part of the body wall is the primary deterrent to predators.The contracted body not only makes a more compact body to bite, but increases the stiffness of the body wall. The sea cucumber also has a very unusual defense mechanism. Many species use the Cuvierian tubules, which are located in the digestive system of the animal to confuse... 

Shelby, M. D., G. L. Erexson, G. J. Hook, and R. R. Tice, Evaluation of a Three-Exposure Mouse Bone Marrow Micronucleus Protocol Results with 49 Chemicals, Environ. Mol. Mutagen., 21, 160-179 (1993). 

Composites provide an atPactive alternative to the various metal-, polymer- and ceramic-based biomaterials, which all have some mismatch with natural bone properties. A comparison of modulus and fracture toughness values for natural bone provide a basis for the approximate mechanical compatibility required for arUficial bone in an exact structural replacement, or to stabilize a bone-implant interface. A precise matching requires a comparison of all the elastic stiffness coefficients (see the generalized Hooke s Law in Section 5.4.3.1). From Table 5.15 it can be seen that a possible approach to the development of a mechanically compatible artificial bone material... 

Shelby, M.D. Witt, K.L. (1995) Comparison of results from mouse bone marrow chromosome aberration and micronucleus tests. Environ, mol. Miitag., 25, 302-313 Shelby, M.D., Erexson, G.L., Hook, GH. Tice, R.R. (1993) Evaluation of a three-exposure mouse bone marrow micronucleus protocol results with 49 chemicals. Environ, mol. Mutag., 21, 160-179... 

Shelby MD, Erexson GL, Hook GJ, et al. 1993. Evaluation of a three-exposure mouse bone marrow micronucleus protocol results with 49 chemicals. Environ Mol Mutagen 21(2) 160-179. 

Tripterygium wilfordii Hook F in CD34-positive human bone marrow cells. Mol Pharmacol 2000 57(3) 512-18. 

Where to Play Estabhshed in 1970, Art Pickering s Provo Turtle Divers (two-tank dives from 99 800-833-1341 provoturtledivers.com) is the oldest scuba center in Turks and Caicos, and still one of the best. If bill-, bone- and fly-fishing are more your thing, try Hook Em Fishing Adventures (from 125 for half-day trips 649-231-3586 hookem.tc). 

After rubber lining, no welding or earthing should be done on the lined tank and therefore the lugs, hooks, pipe supports, which may be required to be welded on the vessel or piping, should have been planned and completed at the time of fabrication of the vessel. The fabricator is normally informed about this in advance. For concrete tanks, the concrete should be bone dry through the entire thickness and the lining surface should be free of dust, cracks, holes, and so on. 

Nitinol has many medical applications, including hooks used by orthopedic surgeons to attach ligaments and tendons to bones and stents that are inserted in partially blocked arteries to keep them open. 

Although bone is a viscoelastic material, at the quasi-static strain rates in mechanical testing and even at the ultrasonic frequencies used experimentally, it is a reasonable first approximation to model cortical bone as an anisotropic, linear elastic solid with Hooke s law as the appropriate constitutive equation. Tensor notation for the equation is written as ... 

In addition to the mechanical tests cited above, ultrasonic wave propagation techniques have been used to measure the anisotropic elastic properties of bone [Lang, 1969 Yoon and Katz, 1976a, b Van Buskirk and Ashman, 1981]. This is possible, since combining Hooke s law with Newton s second law results in a wave... 

As stated earlier, bone (along with all other biologic tissues) is a viscoelastic material. Clearly, for such materials, Hooke s law for linear elastic materials must be replaced by a constitutive equation which... 

Otto von Guericke designed the world s first vacuum pump in 1650. Robert Boyle and Robert Hooke built an air pump in 1656. Pressure exerted by a fluid was found to be inversely proportional to volume, according to the Boyle s law. Denis Pipin, an associate of Boyle, built a bone digester that was used to raise high pressure steam. The idea of a piston and cylinder emanated from Pipin, although Tom Savery built the first engine in 1697. 

From the hook of the hamate bone and flexor retinaculum. 

Midpoint of a line drawn between the hook of the hamate bone and the palmar aspect of the proximal end of the 5th phalanx, the hook of the hamate bone can be felt pressing over the proximal end of the crease between the thenar and hypothenar eminence. 

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