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A Hunding

Publications and source records attributed to A Hunding.

28 records · Page 2Linked to original sources

Bifurcations of nonlinear reaction-diffusion systems in oblate spheroids.

Spontaneous pattern formation may arise in biological systems as primary and secondary bifurcations to nonlinear parabolic partial differential equations describing chemical reaction-diffusion systems. Bipolarity in mitosis and cleavage planes in cytokinesis may be related to this formation of prepatterns. Three dimensional prepatterns are investigated, as they emerge in flattened spheres (i.e. oblate spheroids). Pattern sequences and selection rules are established numerically. The results confirm previously recorded results of the spherical and prolate regions, upon which a prepattern theory of mitosis and cytokinesis is based. Especially, the phenomenon of 90 degree axis tilting and the formation of a highly symmetrical saddle shaped pattern, crucial for the prepattern theory of mitosis and cytokinesis, is examined. Present results show, that these phenomena are stabilized in oblate spheroids. The bipolar "mitosis" prepattern is found as well, although the polar axis may appear with an angle toward the axis of the oblate spheroid. These results are thus further support for the prepattern theory of mitosis and cytokinesis.

Cells↗

Runner's anemia and iron deficiency.

Systemic iron deficiency was found in 63 (56%) of 113 joggers and competition runners (33 women and 80 men). Thirteen women and ten men had latent anemia. A majority of the women were fertile with iron loss from menstruation; the men were runners training long distances. The average transferrin iron-binding capacity was 80 mu mol/l serum in the women and 77 (iron-binding groups) in the men. The haptoglobin and iron concentrations in serum were remarkably low (most often below 10 and 20 mu mol/l, respectively). Three of the long-distance runners ran 25 km daily. They returned with so much free hemoglobin in their plasma that an accompanying iron loss (integrated over months), if not balanced by diet, would lead to iron deficiency and anemia. Oral iron therapy (200 mg ferrous sulphate per day) normalized the hemoglobin concentration and improved the transferrin saturation fraction in 61 persons. The competition runners reported personal records.

Adolescent↗