Showing papers by "Georgia College & State University published in 1977"

Effects of geophagia (kaolin ingestion) on the maternal blood and embryonic development in the pregnant rat.

Abstract: Geophagia, in the form of clay-eating, is often observed during pregnancy in the human population. The intent of this study was to determine the effects of kaolin (clay) ingestion on the maternal blood and embryonic development of the pregnant rat. Thirty-six Sprague-dawley female rats were divided into three groups: control diet, 20% kaolin diet, and iron-supplemented 20% kaolin diet. The diets were fed 37 to 68 days, 69 to 95 days, and 96 to 117 days prior to fertilization, and the same diets were fed for the duration of the gestation period. The rats fed the kaolin diet exhibited significant reductions in hemoglobin, hematocrit, and red blood cell levels, thus indicating maternal anemia. There was also a significant reduction in the birth weight of the pups born to kaolin fed rats. The kaolin fed rats receiving an iron supplement maintained hematocrit, hemoglobin, red blood cell levels, and pup weight within the normal range.

Occlusion effect in bone conduction pure tone and speech audiometry.

Abstract: Two experiments were conducted to determine the occlusion effect (OE) for pure tone and spondee stimuli. Results of experiment I using mastoid placement and unilateral occlusion yielded a mean OE for bone conduction speech reception thresholds of 4.67 dB, which was in agreement with the average OEs of 0.50, 1.0 and 2.0 kHz, or simply the same as the OE for 1.0 kHz. However, the magnitude of the observed OEs for test frequencies of 0.25 to 4.0 kHz was considerably less than the OEs reported in previous investigations. In an attempt to explain this discrepancy, experiment II used unilateral and bilateral occlusion with mastoid and forehead placement for pure tone stimuli. Significant differences (p less than 0.05) were found between OEs obtained with mastoid versus forehead placement and for unilateral versus bilateral occlusion.

Gravitation and electromagnetism

Abstract: We obtain a general relativistic unification of gravitation and electromagnetism by simply(1) restricting the metric so that it admits an orthonormal tetrad representation in which the spacelike vectors are curl-free, and(2) identifying the timelike vector as the potential for an electromagnetic field whose only sources are singularities. It follows that: (A) The energy density is everywhere nonnegative, (B) the space is flat if and only if the electromagnetic field vanishes, (C) the vector potential (through which all curvature enters) admits no invariant algebraic decomposition, and satisfies the covariant Lorentz condition identically, (D) the theory is free of “prior geometry,” (E) the electromagnetic self-energy of a spherically symmetric point charge equalsMC 2 , (F) particles deviate from geodesic motion according to the Lorentz force law with radiative reaction, and (G) particles with all electromagnetic multipole structures are included.