Knowledge Discovery Through Experiential Learning From Business and Other Contemporary Data Sources: A Review and Reappraisal

Every day massive amount of data is generated, collected, and stored in information repositories such as databases and data warehouses. Current information technology is sufficiently mature and powerful to store any amount of raw data in an organized manner. However, finding useful patterns, trends, rules, correlations, and deviations in large amount of data, and/or making meaningful predictions from it still remains one of the main challenges of the information era. The more data one has, the more difficult it is to analyze and draw meaningful conclusions. Knowledge discovery in databases (KDD) and data mining (DM) is a field, which uses computer-based and analytic technologies to efficiently extract intelligence from data that humans need. In this article, we review the process of knowledge discovery in databases, and describe selected methodologies, methods and tools, tasks, basic learning paradigms, and applications for knowledge generation by computer learning from data instances. We also examine the current trends in the field with respect to the data types mined, data mining methods used, classes of data mining applications, as well as the data mining software used. © Taylor & Francis Group, LLC

Ultrastructural Analysis of Folliculogenesis in the Ovary of the Yellow Spotted Stingray, Urolophus jamaicensis

The ovary of the yellow spotted ray, Urolophus jamaicensis, is embedded in the epigonal gland, a lymphomyeloid organ. The covering of the ovary is composed of a germinal epithelium that is cuboidal and dome-shaped with microvilli. Adjacent cells have elaborate intercellular folds that create dilated intercellular spaces. In previtellogenic follicles, the follicle cells are simple cuboidal and contain modest amounts of synthetic or transport organelles. As vitellogenesis proceeds, the epithelium becomes multilaminar. Follicle cells are columnar as yolk precursors are transported from the maternal circulation, through the follicle cell cytoplasm, to the oocyte. Large, round cells occur in the follicle wall that contain lipid-like substances. These cells decrease in size and number as folliculogenesis proceeds and eventually disappear prior to ovulation. Columnar follicular cells and the oocyte have cellular extensions that impinge upon the zona pellucida. Transosomes are follicle cell extensions that indent the oocyte membrane. Tips of transosomes become enclosed by a layer of oocyte plasmalemma. The tips of transosomes pinch off and become resident in the ooplasm. Dense staining material occurs on the inner surface of the transosome membrane derived from the follicle cell. In other animals, this material has been described as ribosome-like. This study is the first to document the presence of transosomes in a group other than Aves or reptiles. Follicle cells are supported by an extremely thick basal lamina. Subjacent to the lamina is the vascularized theca with fibroblasts embedded in a collage-nous network. There is no differentiation into definitive theca interna and externa. In vitellogenic eggs, extensive inward foldings of the follicular epithelium occur thereby generating more surface area for the transport of yolk precursors to the oocyte. Atretic follicles are common