Based on this classification, the difficulty of extraction was evaluated using difficulty index described by Pederson [6].
Moreover, despite its significant antileukaemic activity, its difficult production, the unreliability of source supply, the difficulty of extraction and the low level of purity of product limited its evaluation in large randomised studies or its use in clinical practice.
He notes the huge amounts of water that shale gas extraction requires, and the other legal and bureaucratic difficulties of extracting it.
Similarly, there were intraoperative difficulties in 10 (83 %) cases: 6 cases (i.e., 50%%) of severe adhesions, four cases of difficulties with extraction of the neonate, 2 cases of bladder laceration, 1 case of uterine atony, and 1 case of difficult placental retrieval.
However reliability of the data extraction from GP records will be examined in a core set of variables which cover the range of difficulty and modes of extraction from GP records.
However, difficulties of complex dimerization and extraction of the product and catalyst from solution, as well as the endeavor of modeling natural enzymatic systems, stimulated the research of synthesis of immobilized homogeneous catalysts of oxidation including complexes with Schiff bases [3].
Building on this theoretical distinction, we posit that attentional selection of other-species targets might be preserved, but their identification might be impaired as a result of difficulties in the extraction or maintenance of task-specific representations in the early phases of visual search that precede attentional selection.
Currently, these residues are disposed of by burning or shredding, not being exploited because of several technical difficulties in extraction, handling and transport as well as because of the lack of accurate data on the quantity and suitability of these residues.
This greatly increases the difficulties of the BM target feature extraction task.
This fact is the nature of difficulties in feature extraction.
