A young scientist and mathematician explores the mystery and complexity of human thought processes from an interdisciplinary point of view.

Apical cells are universally present in lower plants and their description has been mostly viewed morphologically as single-celled meristems. This study attempts to demonstrate that the roles of apical cells and more generally of meristems collectively are (a) often the proliferative source of all cells in a plant, (b) sometimes a formative centre in histogenesis and organogenesis and (c) always a regulatory site. As a proliferative centre it occurs as a series of apical cells through a mitotic lineage by unequal (...) divisions which includes a rotational pattern to form cells distributed according to the symmetry of its organ. As a formative centre it determines leaf arrangement in mosses and leafy liverworts as well as the root cap and gametophyte cushion in ferns. It appears initially to determine the type of organ and later the organ determines the type of apical cells within. As a regulatory centre it activates distal secondary cells to proliferate as well as inhibiting neighbouring cells from becoming apical cells to preserve the identity of an organ during its development.Based on these three roles by which apical cells can be recognized an argument can be drafted that seed plants may have apical cells, although morphologically indistinguishable from other cells, singularly or in batteries instead of possessing the traditionally described multicellular meristems. (shrink)

The levels that compose biological hierarchies each have their own energetic, spatial and temporal structure. Indeed, it is the discontinuity in energy relationships between levels, as well as the similarity of sub-systems that support them, that permits levels to be defined. In this paper, the temporal structure of living hierarchies, in particular that pertaining to Human society, is examined. Consideration is given to the period defining the lifespan of entities at each level and to a periodic event considered fundamental to (...) the maintenance of that level. The ratio between the duration of these two periods is found to be approximately 2.5 × 104. A similar relationship is found when lower, non-living levels of molecules and atoms are considered. This suggests that there is a constant factor of amplification between analogous periodic events at successive levels of the Human hierarchy. (shrink)

Lucid, non-intimidating presentation of propositional logic, propositional calculus and predicate logic by Russian scholar. Topics of concern in a variety of fields, including computer science, systems analysis, linguistics, etc. Accessible to high school students; valuable review of fundamentals for professionals. Exercises (no solutions). Preface. Three appendices. Indices. Bibliogaphy. 14 figures.