Initiation history

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Research into the biological activity of phytochemicals has a long history. Initially, the focus was on natural product chemistry, with degradation studies providing a basis for structure determination that was confirmed by elegant multistage synthesis. Many key reactions of organic chemistry were first developed out of the specific synthetic requirements of this area. 

The proportion of life occupied by delamination growth is a small fiaction of the total as growth rates are fast. The onset of delamination growth is sensitive to load history initiation of growth is more difficult than its propagation. 

LV pacing has undergone considerable evolution in its short history. Initially, pacemaker electrodes were placed in the coronary sinus using a stylet-driven technique. This has evolved to the currently acceptable use of a guiding catheter contrast venography for either a stylet-driven or some form of guidewire-assisted placement. 

Aromaticity in compounds containing a transition-metal atom has already had a long history. Initially, Thom and Hoffmann [34] proposed six-membered ring met-allocyclic compounds, derivatives of benzene with one C-H moiety replaced by an isolobal transition-metal fragment. Three years later the first example of a stable. 

To support mode history, initial and activation modes are distinguished. This allows to express that after a re-activation of a component due to a system reconfiguration, the component should resume its operation in the state in which it had previously been deactivated. 

Figure 10 The historiated initials (A) P and (B) S from the Icelandic Jonsbdk with the Raman spectra of pigments contained therein. The combination of vermilion and red ochre in the P should be noted. The spectrum of bone white has been obtained from the letter H (not shown). Reproduced with permission from Best SP, Clark RJH, Daniels MAM, Porter CAand Withnall R (1995). Identification by Raman microscopy and visible reflectance spectroscopy of pigments on an Icelandic manuscript. Studies in Conservation 40 31-40. (See Colour Plate 4.)...

Figure 11 Elaborately historiated initial R in sixteenth-cerrtury German choir book, with Raman microscopy spectra of selected pigmented regions. Reproduced with permission of Clark RJH (1995) Raman microscopy application to the identification of pigments on medieval manusorlpts. Chemical Society Reviews 187-196 The Royal Society of Chemistry. (See Colour Plate 5a).

Raman microscopy vermilion, orpiment, realgar, red ochre, azurite and bone white. Neither red lead nor lead white, pigments commonly used in Northern Europe, was identified on the manuscript this raises questions as to the availability of these pigments in Iceland, to which they are not native, and of the effectiveness of the trading routes. Examples of two historiated initials and the Raman spectra of the pigments used are shown in Figure 10. 

An elaborately historiated initial R on a sixteenth-century German choir book has been studied by Raman microscopy and no fewer than eight pigments have been identified, namely, azurite, lead tin yellow, malachite, vermilion, white lead, red lead, carbon and massicot (Figure 11). 

Plate 5a Elaborately historiated initial R in sixteenth-century German choir book, with Raman microscopy spectra of selected pigmented regions. See Art Works Studied using IR and Raman Spectroscopy. 

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