The problem of indexing multidimensional objects is considered. First, a classification of existing methods is given along with a discussion of the major issues involved in multidimensional data indexing. Second, a variation to Guttman’s R-trees (R+-trees) that avoids overlapping rectangles in intermediate nodes of the tree is introduced. Algorithms for searching, updating, initial packing and ...

The present study was aimed at the development of a somoclonal variant and isozyme marker for Phyllanthus amarus Schum & Thonn using inter-nodal segments and the enzyme peroxidase. Maximum callus proliferation was obtained on Murashige and Skoog’s medium supplemented (MS) with 1.0 mg/l of 2,4-Dichlorophenoxyacetic acid. Three weeks-old pale yellowish white semi-friable callus was used for organ...

Nitrogen plays a pivotal role in growth and differentiation of cells of Phyllanthus amarus Schum. and Thonn. Both form and amount of nitrogen in nutrient medium have significant effects on the rate of cell growth and differentiation. In this study, effects of different inorganic nutrients (KNO3 and NH4NO3) and organic nutrients (glycine) on regeneration of P. amarus were evaluated. Murashige an...

Background: A total of 30 endophytic fungi (AAP-PS 1–30) were isolated from the medicinal herb Phyllanthus amarus and screened for the production of Trichothecinol-A. Out of all the endophytic strains screened for Trichothecinol-A production, the culture filtrate of AAP-PS-1 extracted with ethyl acetate yielded Trichothecinol-A extracellularly in appreciable amounts. Trichothecinol-A was purifi...

It is shown that for a metric space (M,d) the following are equivalent: (i) M is a complete R-tree; (ii) M is hyperconvex and has unique metric segments.

We present a new spatial index belonging to R-tree family. Since our new index comes out from the R-tree and holds the concept of nonoverlapping nodes we call it R-tree. The original R-tree was designed for both point and spatial data. Using R-tree for indexing spatial data is very inefficient. In our research we face the problem of indexing product catalogues data that can be represented as po...