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Full-Text Articles in Life Sciences
The Columnar Junipers Of Western North Dakota (An Investigation Into The Cause Of Their Columnarity), James M. Murphy
The Columnar Junipers Of Western North Dakota (An Investigation Into The Cause Of Their Columnarity), James M. Murphy
Electronic Theses and Dissertations
The objective of this report is to focus on the evaluation of the presence and amount of ethylene in the burning lignite fumes and to search for morphogenetic factors in the lignite at the Slope County site. The former was considered to be more important and was investigated more thoroughly.
Effects Of Ay On Preimplantation Embryo Lethalities (Ay/Ay) And On Abnormal Mating Behavior (Ay/A) In Strain C57bl/6j Mice, Kevin Thomas Brock
Effects Of Ay On Preimplantation Embryo Lethalities (Ay/Ay) And On Abnormal Mating Behavior (Ay/A) In Strain C57bl/6j Mice, Kevin Thomas Brock
Electronic Theses and Dissertations
The immediate objectives of the studies to be presented were (1) to establish the presence and characterize the morphology of the Ay/Ay homozygotes before and after implantation, (2) describe the relationship between embryo and uterus, (3) characterize prenatal and neonatal losses occurring to the Ay/a mouse, and (4) test the randomness of mating selection of the Ay/a mouse. To meet the objectives, data collected from the complete serial section of embryos in utero at 90 and 132 hours post coitum (hpc) from matings of yellow females (Ay/a) by yellow males (A …
Cell Surface Changes During Early Mouse Development, James Thomas Rector
Cell Surface Changes During Early Mouse Development, James Thomas Rector
Electronic Theses and Dissertations
Objectives of this thesis were to further characterize cell surface properties of preimplantation mouse embryos. A study was conducted to determine latent effects of varying pulses of CB on early postimplantation mouse embryos by comparing their abilities to hatch, to attach and to sustain growth and differentiation of ICM and trophoblast tissue. CB treatment was begun at the 8-cell stage. Objectives of the studies involving Con A were to determine (1 ) whether agglutinability with Con A changes during compaction of 8-cell embryos, (2) if changes in numbers of binding sites parallel changes in agglutinability during preimplantation development, (3) whether …
Observations On Attachment And Spreading Of Zonaless Tw32/Tw32 (Brachyury Locus) And Control Icr Preimplantation Mouse Embryos, Ker Hwa Tung
Observations On Attachment And Spreading Of Zonaless Tw32/Tw32 (Brachyury Locus) And Control Icr Preimplantation Mouse Embryos, Ker Hwa Tung
Electronic Theses and Dissertations
The objective of the first part of this thesis is to test, in vitro, the adhesiveness of different stages of denuded preimplantation ICR mouse embryos for the substratum. In the second part, experiments are conducted to determine if there are differences in the attachment and spreading potential between tw32 homozygotes and normal embryos. Studies by Spiegelman (1976), Calarco and Brown (1968), Granholm and Johnson (1978), and others indicate that t12, tw32 and other lethal t alleles of the Brachyury or T-complex may affect cell surface properties. Thus, the objectives of this thesis include the acquisition of …
Effects Of Gamma Radiation On The Southern Corn Rootworm, Denise Gayle Hanson
Effects Of Gamma Radiation On The Southern Corn Rootworm, Denise Gayle Hanson
Electronic Theses and Dissertations
Insects continue to be one of the major problems of man. It is, however, becoming more and more difficult to find substances that are effective in controlling insects and that are environmentally safe. It has become apparent that to control or eliminate harmful insects, alternate methods of control must be developed to replace or reduce the use of insecticides. One possible alternate method of control is to use insects against themselves in a process called the sterile male technique. This technique generally uses gamma radiation to induce sterility in males. When they are released into the native population and mate …
The Vegetational Composition Of The Samuel H. Ordway Memorial Prairie, Fred K. Carl
The Vegetational Composition Of The Samuel H. Ordway Memorial Prairie, Fred K. Carl
Electronic Theses and Dissertations
This thesis represents the first half of a two year study of the vegetational composition of the Samuel H. Ordway, Jr. Memorial Prairie. Quadrat and point frame sampling was completed along 100 transects distributed over the 10 pastures. Biomass for the study area was determined to be 133. 3 g•m-2 for live weight and 104.0 g•m-2 for mulch. Basal cover for Ordway Prairie was found to be 12.5%. The study area was found to be predominantly occupied by warm season species. Andropogon scoparius was found to be highest in relative density while Carex was highest in relative frequency. …
Anatomical Studies During Floral Induction, Evocation And Initiation In Eucharis Grandiflora, Planch., The Amazon Lily, Raphael T. Deba
Anatomical Studies During Floral Induction, Evocation And Initiation In Eucharis Grandiflora, Planch., The Amazon Lily, Raphael T. Deba
Electronic Theses and Dissertations
Several questions were posed at this point which led to the hypotheses to be tested in this investigation. The experimental design was divided into 3 phases. For a detailed description of the design, see Appendix A. Phase I of this study involved a comparative study of the anatomy of the apices of plants of Eucharis grandflora, the Amazon lily, exposed to heat (27-29° C) for one, two, three, four or five weeks, in an effort to see if manifestations of floral evocation and/or initiation are in evidence when compared to the control. Since the time from the end of heat …
Primary Productivity In Lake Cochrane, South Dakota, During And After Sediment-Control Dam Construction, Randall Francis Brich
Primary Productivity In Lake Cochrane, South Dakota, During And After Sediment-Control Dam Construction, Randall Francis Brich
Electronic Theses and Dissertations
Lake Cochrane was selected for this study because of its history of superior water transparency (Haertel 1972, 1976b). Significant amounts of silt and chemicals enter the lake with runoff at 3 locations (Haertel unpublished data). Restriction or impediment of runoff at these locations should result in improved water transparency (Haertel 1976b, Siegel 1975). Therefore, East Dakota Conservancy Sub-District and the South Dakota Department of Wildlife, Parks, and Forestry decided to impede runoff waters by means of 3 sediment-control dams incorporated into the perimeter road system of the lake and financed through a grant from the Environmental Protection Agency (Siegel 1975) …
A Study Of The Macrobenthic Community In Lake Cochrane, South Dakota, David R. German
A Study Of The Macrobenthic Community In Lake Cochrane, South Dakota, David R. German
Electronic Theses and Dissertations
As part of a continuing study of the biological community of Lake Cochrane, South Dakota, a quantitative survey of the macroscopic bottom fauna was made between the early part of April, 1976 and December, 1976. It was hoped that such a study could provide baseline data for an understanding of the interactions that occur between benthic organisms and other biological components of the lake system. The lake's primary productivity and phytoplankton and zooplankton standing crops have previously been studied by Haertel (1972, 1976) and Steinberg (1972). When this study was being conducted, sediment control dams were being built on three …