Active islands

Hoogewerff JA, van Bergen MJ, Vroon PZ, Hertogen J, Wordel R, Sneyers A, Nasution A, Varekamp JC, Moens HLE, Mouchel D (1997) U-series, Sr-Nd-Pb isotope and trace-element systematics across an active island arc-continent collision zone impUcations for element transfer at the slab-wedge interface. Geochim Cosmochim Acta 61 1057-1072... 

Another group has evaluated self-organizing maps [63] and shape/ pharmacophore models [64]. They developed a new method termed SQUIRREL to compare molecules in terms of both shape and pharmacophore points. Thus from a commercial library of 199,272 compounds, 1926 were selected based on self-organizing maps trained on peroxisome proliferator-activated receptor a (PPARa) "activity islands." The compounds were further evaluated with SQUIRREL and 7 out of 21 molecules selected were found to be active in PPARa. Furthermore, a new virtual screening technique (PhAST) was developed based on representation of molecules as text strings that describe their pharmacophores [65]. 

Partially Blocked Active Electrode and Active Islands on Inactive Electrode... 

Composite electrodes used in the electrochemical processes are often partially active since they are composed of the active powder material and the inactive binder and conductor. The partially blocked active electrode can be characterized by the contiguous fractal with dy < 2.0. In the case of the electrodes composed of the active islands on an inactive support, they are characterized by the non-contiguous fractal with dy < 2.0.121... 

A similar idea has been expressed by Cramer and co-workers as trying to find the activity island [10], It should be noted that this approach does make the implicit assumption that there is reliable information in inactive compounds, an idea that we are not entirely comfortable with. 

The existence of positive relief features and mountains is an almost self-explanatory indication that the rates of uplift of some continental sections have been much higher than the rates of denudation (Fig. 2). The rates of erosion that about balance or are slightly below the rates of uplift characterize the stable shield areas of South America, 10-20 mm ka and a tectonically active island Formosa (Taiwan), where uplift rates are as high as 103-104 mmka-1 (Stallard, 1988). 

For lead finding, the use of chemical compound collections and combinatorial libraries is indispensable to every pharmaceutical company for a timely and efficient discovery of novel bioactive entities [5]. Until recently, most attention was paid only to internal historic compound collections, maintained over several years of medicinal research [6]. Flowev-er, those libraries typically contain a limited number of structural classes as the result of past research projects which focused on biological activity islands .Today there is a growing interest in techniques that expand structural and - even more important - biological diversity, this perhaps being accomplished by the direct acquisition of an external compound collection, or by the use of internal or external synthesis capacities [7]. 

Bargagli, R., Barghigiani, C., Siegel, B.Z., Siegel, S.M., 1991. Trace metal anomalies in surface soils and vegetation on two active island volcanoes Stromboli and Vulcano (Italy). Sci. Total Environ. 102, 209-222. 

---