Butterfly Fragment

Note that the common fragment appears to be a 22 eve butterfly fragment (like B4H10) rather than a ring isoelectronic with C4H8. We will encounter this ambiguity for metal clusters as well when cluster fusion involves four common atoms. 

Comminuted fractures include segmental fractures and those with butterfly fragments. Open or compound fractures occur when a wound extends from the skin surface to the fracture. 

Fig. 8.2a-e. The pattern of a fracture is determined by the forces applied to produce it. a Spiral fracture is the result of twisting/torsional forces, b Oblique fracture due to compressive forces, c Oblique fracture (with small transverse element) due to the bone being held fast and an uneven bending force applied distal to the fracture, d Transverse fracture due to bending force about a fulcrum, e-a Butterfly fragment due to compression and bending forces... 

Fig. 9.2. a Femoral shaft fracture with large butterfly fragment. Since the proximal capital physis is closed, a locked intramedullary nail can be inserted. This nail has been introduced via the piriformis fossa. This is a very unstable fracture, b Image intensifler view of distal femoral locking bolt, c Only an accurate lateral view of the femur confirms that the locking screw has passed through the nail and not in front or behind. The screw obscures the distal hole. The more proximal distal locking hole has not been utilized. 

Fig. 7. The solid state structures of the di(pyridyl)methanide [53], -amide [52], -phos-phide[27] 13 and -arsenide [43] all containing the Me2Al cationic fragment. Although the Al-N distance is almost invariant in all structures the more acute C-E-C angle (As < P < N < CH) forces the complex in a more pronounced butterfly arrangement...

By slight modification of the synthetic procedure outlined in Equation (35), a P2 unit side-on bound to two Ni° complex fragments can be obtained according to Equation (36) (1060). X-ray crystallography shows a butterfly structure with d(P=P) = 2.121(6) A 2 48... 

The equivalent of the tryptic fragment of human transferrin receptor has been expressed in Chinese hamster ovary cells and its structure determined at a resolution of 0.32 nm (Lawrence et ah, 1999). The asymmetric unit of the crystals contains four transferrin receptor dimers. Interpretable electron density is found for the entire tryptic fragment except for Arg-121 at the amino terminus, and density is also seen for the first N-acetylglucosamine residue at each of the N-glycosylation sites. The transferrin receptor monomer is made up of three distinct domains, organized such that the dimer is butterfly shaped (Figure 5.10, Plate 7). The likely orientation of the dimer with respect to the plasma membrane has been assigned on the basis of the... 

The fragmentation is stereospecifically anti as shown by complementary geometry obtained in the cleavage of the epimeric pair of epoxycyclobutanones 91 and 92 (Eq. 110). The fragmentation product 93 of cyclobutanone 91 is transformable into the dimethyl ester of the pheromone of the Monarch butterfly. Considering the availability of the starting epoxy ketones from enones, the oxasecoalkylation serves to reorient the oxidation pattern with chain extension as summarized in Eq. 111. 

Bomb Nose M.T Fuze M129 (Fig 4-24), designed for aerial burst or impact, is used only with the fragmentation (butterfly) bombs assembled in clusters. Its body diam is 1.75-in, overall length 3.0-in, and wt 0.4-lb. It is equipped with primer M41A1, detonator M31, and booster contg Tetryl pellet in a metal cup... 

M31 and Tetryl pellet booster. Designed for use with the fragmentation (butterfly) bomb, it can be set either for "GROUND " action (by impact) or for "AIR" burst, preset for delays 10, 20, 30, 40, 50 or 60 minutes after arming. Arming takes place after 50 -ft of air travel... 

Bomb Nose MT Fuze M131A1 (Fig 4-26) is designed for use only with fragmentation (butterfly) bombs assembled in clusters. 

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