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Full-Text Articles in Life Sciences

A Survey Of The Helminth Parasites And Coccidia Of Cattle And Sheep In Utah Valley, Joseph Carl Fox May 1970

A Survey Of The Helminth Parasites And Coccidia Of Cattle And Sheep In Utah Valley, Joseph Carl Fox

Theses and Dissertations

A survey of gastro-intestinal parasites in cattle and sheep in Utah Valley was conducted. Cattle in the valley were not seriously parasitized by helminths, whereas sheep usually had heavy helminth infections. Ten genera of helminths and 8 species of coccidia were identified in cattle in the valley, and 14 genera of helminths and 8 species of coccidia were identified in sheep. In conjunction with the survey, meteorologic studies were conducted May through September, 1909, to ascertain the effects which irrigation had upon micro-environments on grass pastures in relation to the development of free-Iiving stages of gastro-intestinal nematodes of ruminants. The …

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A Comparison Of Vegetation Changes In A Mountain Brush Type After Grazing And Protection From Grazing During Thirty-Seven Years, Jerry William Thomas May 1970

A Comparison Of Vegetation Changes In A Mountain Brush Type After Grazing And Protection From Grazing During Thirty-Seven Years, Jerry William Thomas

Theses and Dissertations

The mountain brush type in Utah was studied in 1932, 1942, and 1969 to determine the vegetation changes and trends after grazing and protection from grazing for 37 years. Analyses for cover, frequency and composition percentages, production and plant counts were made on fifty 100 square-foot plots in a ten-acre exclosure and on a five-acre grazed area adjacent to the exclosure. Production, cover and composition percentages for good and fair forage species of grasses and browse have decreasesed on the grazed plots whereas they generally increased in the ungrazed plots. Forbs of intermediate forage value have increased in production, cover …

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The Effects Of Euploid Changes In Chromosome Number On Various Physiological Factors In Tomatoes, Barley And Rye, Larry Wayne Peterson May 1970

The Effects Of Euploid Changes In Chromosome Number On Various Physiological Factors In Tomatoes, Barley And Rye, Larry Wayne Peterson

Theses and Dissertations

Leaf tissue of diploid, triploid, and tetraploid tomatoes (var. UF-36) and diploid and tetraploid barley (var. Steel and Midsummer) were analyzed for total chlorophyll, soluble protein, dry weight, ribulose-1,5-diphosphate carboxylase, phosphoribulokinase, and peroxidase. Polyploidy caused a slight increase of all factors in Midsummer rye, had a variable effect on Steel rye and Everest barley, and caused a reduction in tomatoes and Barbless barley when the factors were determined on a fresh weight basis. In tomatoes, if the ribulose-1,5-diphosphate carboxylase activity was determined on protein content, dry weight or cell number the tetraploid form had higher activity than the diploid form. …

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Taxonomy And Ecology Of Fungi Imperfecti From Four Locations In Utah Lake, Utah Co., Utah, Laird Max Hartman May 1970

Taxonomy And Ecology Of Fungi Imperfecti From Four Locations In Utah Lake, Utah Co., Utah, Laird Max Hartman

Theses and Dissertations

Fungi imperfecti were cultured from water and bottom sediment samples collected at four locations of Utah Lake. These study sites included: (a) The mouth of Provo River, the largest fresh-water tributary entering Utah Lake, (b) Mud Lake, a large shallow area known for its high nitrogen content, (c) the entrance of the Spanish Fork River into the lake, a large fresh-water tributary containing wastes from industry and agricultural enterprises, (d) Jordan River, the only natural outlet of Utah Lake. One hundred and thirty-eight species of fungi imperfecti were identified. A total of 89 species were isolated from the Spanish Fork …

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The Effect Of Alternate Year Rest Rotation Grazing On Carbohydrate And Nitrogen Reserves In Crested Wheatgrass, James B. Wood May 1970

The Effect Of Alternate Year Rest Rotation Grazing On Carbohydrate And Nitrogen Reserves In Crested Wheatgrass, James B. Wood

Theses and Dissertations

A field and laboratory study was made to determine the effect of alternate year rest rotation grazin in stem bases and root crowns of crested wheatgrass. Analyses for carbohydrate reserves and total nitrogen were made for the following treatments: (1) exclosures; (2) open range; (3) agronomy cages. Both carbohydrate concentration and total nitrogen content showed differences between sampling dates but did not show differences as a result of grazing treatment on individual dates. Differences between sampling dates were associated with season and growth stage of plants. Although differences due to grazing teatment were not shown for individual dates the combined …

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Changes With Growth In Selected Body Proportions Of The Woundfin Minnow (Plagopterus Argentissimus Cope: Cyprinidae), Edward James Peters May 1970

Changes With Growth In Selected Body Proportions Of The Woundfin Minnow (Plagopterus Argentissimus Cope: Cyprinidae), Edward James Peters

Theses and Dissertations

In this study 883 specimens of the woundfin minnow (Plagopterus argentissimus Cope) from the Virgin River in Utah, were weighed and measured. Ratios of body measurements to standard length, and gonad weight to total weight were calculated. From the gonad weight:total weight ratios it was determined that woundfins spawn during a period from April through June, and that the first significant gonad development is during the third year of life. Several body proportions such as, snout length, gape, upper jaw length and peduncle depth grew nearly isometrically. Growth of other body proportions was more or less allometric. Head length, body …

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Asymptotic Evaluation Of Wkb Matrix Elements. Ii. Use Of Langer's Uniform Asymptotic Wavefunctions, Wesley D. Smith, Russell T. Pack Feb 1970

Asymptotic Evaluation Of Wkb Matrix Elements. Ii. Use Of Langer's Uniform Asymptotic Wavefunctions, Wesley D. Smith, Russell T. Pack

Faculty Publications

An improvement in a previous procedure for the analytic asymptotic evaluation of integrals arising in the quantum-mechanical theory of inelastic molecular collisions is presented. The integrals are evaluated using Langer's uniform asymptotic wavefunctions and the higher-order saddle-point or steepest-descents method. It is found that the Langer functions give no better results than WKB functions, but the higher-order steepest-descents corrections produce a marked improvement. The result is a simple method for evaluating a large class of integrals with an error of 0.1%-2.1%.

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Quasilattice Interpretation Of The Thermodynamic Properties Of Mixing Of Binary Alkali-Metal Systems, J. Bevan Ott, J. Rex Goates Nov 1969

Quasilattice Interpretation Of The Thermodynamic Properties Of Mixing Of Binary Alkali-Metal Systems, J. Bevan Ott, J. Rex Goates

Faculty Publications

Quasilattice theory was applied to heats of mixing in the six systems formed from the binary combinations of Na, K, Rb, and Cs. The alkali-metal systems are particularly well suited for a critical test of the quasi-crystalline assumption since the theoretical model for these systems is relatively simple and the thermodynamic data are fairly complex. Very good fits of the heat-of-mixing data were achieved by assuming that the larger atom in the binary system covered multiple sites on the quasilattice. The values of the empirically determined constants appear to fit the physical significance accorded to them by the quasilattice model. …

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Front Matter, Vol. 10 No. 4 Oct 1969

Front Matter, Vol. 10 No. 4

Brigham Young University Science Bulletin, Biological Series

No abstract provided.

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End Matter, Vol. 10 No. 4 Oct 1969

End Matter, Vol. 10 No. 4

Brigham Young University Science Bulletin, Biological Series

No abstract provided.

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Nesting Ecology Of Raptorial Birds In Central Utah, Joseph R. Murphy, Franz J. Camenzind, Dwight G. Smith, J. Bradford Weston Oct 1969

Nesting Ecology Of Raptorial Birds In Central Utah, Joseph R. Murphy, Franz J. Camenzind, Dwight G. Smith, J. Bradford Weston

Brigham Young University Science Bulletin, Biological Series

No abstract provided.

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A Taxonomic And Ecological Study Of The Desmids Of Lily Lake, James L. Pederson Aug 1969

A Taxonomic And Ecological Study Of The Desmids Of Lily Lake, James L. Pederson

Theses and Dissertations

During the summero f 1964 a taxonomica and ecological study was made of the desmids (microscopic green algae) found in Lily Lake. The study site is a subalpine lake in the Wasatch National Forest of the Uinta Mountains, Utah. The lake is located about one-half mile west of Trial Lake at an elevation of approximately 10,000 feet. The lake is an acidic, cold, lentic bog pond characteristic of this region. Desmids were collected at weekly intervals from seven sampling sites. The water temperature, pH, dissolved oxygen, light conditions and length of day from sunrise to sunset were recorded at the …

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An Investigation Of A Mycorrhizal Association On Opuntia Polyacantha, R. Craig Stutz Aug 1969

An Investigation Of A Mycorrhizal Association On Opuntia Polyacantha, R. Craig Stutz

Theses and Dissertations

Roots of Opuntia, polyacantha Haw. from Juab County, Utah were found to be nodulated. An anatomical study of the nodulated roots showed them to be ectotrophic mycorrhizae. Fusarium poae (Peck) Wollenweaver was found associated with the nodules both as an epiphyte and an endophyte. However, reinfection with this organism failed to induce subsequent nodulation. Under certain conditions the roots of o. polyacantha are able to overcome the mycorrhizal infection and elongate. It is not uncommon for several branch roots to originate from a single nodule. It is suggested that the fungus-root association found in o. polyacantha represents an early stage …

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The Migratory Route Of Toxocara Canis In Gerbils, Thomas Carl Baker Aug 1969

The Migratory Route Of Toxocara Canis In Gerbils, Thomas Carl Baker

Theses and Dissertations

Toxocara canis (Werner, 1782) is the round worm most frequently found in dogs. From surveys in the United States, approximately 40-100% of young dogs and 5-70% of older dogs are infected with this parasite. Of 97 adult dogs surveyed in Provo, Utah, in 1968, 17. 5% were infected with T. canis (Fox, personal communication). Adult dogs become infected by ingesting food contaminated with the infective eggs from this parasite. Puppies are most frequently infected prenatally from their mother (Nifontov, I 949; Yutuc, 1949; Sprent, 1958; Webster, I 958; Douglas and Baker, 1959; Scothorn, Koutz and Groves, 1965; Wiseman. 19 69).

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Winter Behavior And Population Dynamics Of American Eagles In Western Utah, Clyde C. Edwards Aug 1969

Winter Behavior And Population Dynamics Of American Eagles In Western Utah, Clyde C. Edwards

Theses and Dissertations

The large size, extensive range, and irnporta.nt corrnnunity role of the Golden Eagle (Aguila chrysaetos L.) and the Bald Eagle (Haliae-etus leucocephalus L.) attract considerable scientific interest. Sorne aspects of their life history have been investigated and reported in detail, but their rapidly declining numbers (Sprunt and Ligas 1966, Cottam 1961) necessitate new investigations into all phases of their life history and particularly into population dynamics.

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Age And Growth Of White Bass, Roccus Chrysops (Rafinesque), In Mud Lake, Near Provo, Utah, Frederick Edward Trapnell Aug 1969

Age And Growth Of White Bass, Roccus Chrysops (Rafinesque), In Mud Lake, Near Provo, Utah, Frederick Edward Trapnell

Theses and Dissertations

This study was conducted to obtain information that could be used in the management of the Utah and Mud lake white bass fishery. It also provides data for evaluating the effect of the loss of Mud Lake on the white bass utilizing it. Determination of age, growth rate, and coefficient of condition of the Mud lake white bass were objectives in this study. The occurrence of organisms in the digestive tracts of 64 white bass as well as the movement of white bass into and out of Mud Lake were also studied. Hoop nets, a continuous mesh gill net, and …

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A Revision Of The Genus Eriogonum (Polygonaceae), James Lauritz Reveal Aug 1969

A Revision Of The Genus Eriogonum (Polygonaceae), James Lauritz Reveal

Theses and Dissertations

The genus Eriogonum is one of North America's largest and most complex group of plants. Found primarily in the western United States where its members are a common feature of the landscape, its overall range is from Alaska to central Mexico and from the Pacific coast to the Atlantic coast. The genus is composed of eight subgenera and 226 species. The purpose of the dissertation is to present an abbreviated revision of the genus following the style format of the North American Flora series. Brief taxonomic descriptions and keys are provided along with details of each taxon's geographical distribution and …

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Ultrastructural Investigations Of Tilletia Caries Teliospores, James Vincent Allen Aug 1969

Ultrastructural Investigations Of Tilletia Caries Teliospores, James Vincent Allen

Theses and Dissertations

The purpose of this study was to investigate the ultrastructure of Tilletia caries teliospores. Specimens were prepared for viewing in the electron microscope by freeze-etching and thin-sectioning techniques. Thin-sectioning techniques gave excellent results with the teliospore walls and the lipid bodies within the teliospore but failed to adequately fix the membranes and internal organelle systems. Micrographs of Tilletia caries teliospores prepared using thin-sectioning show three major wall layers and two partition wall layers and abundant lipid bodies. The freeze-etch method of spore preparation proved superior to the thin-sectioning used in this study to reveal the internal organelle systems of the …

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The Effect Of Chemical Adjuvants Of The Survival Of The Free-Living Stages Of The Gastrointestinal Nematode, Haemonchus Contortus, Anthony T. Chang Aug 1969

The Effect Of Chemical Adjuvants Of The Survival Of The Free-Living Stages Of The Gastrointestinal Nematode, Haemonchus Contortus, Anthony T. Chang

Theses and Dissertations

Considerable research has been done on the influence of various chemical adjuvants, such as glycerol and dimethyl sulfoxide (DMSO) on the survival of protozoan organisms. (Levine and Marquardt, 1955; Levine, Mizell and Houlahan, 1958; Levine, et al. 1962; Levine and Andersen, 1965, 1966; Fitzgerald and Levine 1957 1 1961; Diamond, 1964). Considerably less work has been done on metazoan parasites. The effects of various chemical adjuvants on the survival of Haemonchus contortus, the large stomach worm of sheep, at extremely low temperatures has not been reported. The purpose of this research was to determine if different concentrations of chemical adjuvants …

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Surface Characteristics Of Conidia From Monosporous Cultures Of Penicillium Digitatum And Aspergillus Nidulans Var. Echinulatus, Raymond Kunito Fuji Aug 1969

Surface Characteristics Of Conidia From Monosporous Cultures Of Penicillium Digitatum And Aspergillus Nidulans Var. Echinulatus, Raymond Kunito Fuji

Theses and Dissertations

The purpose of this investigation was to evaluate the possible taxonomic significance of the "rodlet" patterns and spore wall configurations of conidia from monosporous cultures of Penicillium digitatum Saccardo and Aspergillus nidulans Eidam var. echinulatus Fennell & Raper. Freeze-etching the conidiospores from single spore isolates of these fungi revealed that spore wall patterns and configurations vary much too greatly to be of taxonomic importance on the strain and subspecies level. Environmental factors and genetic influences are discussed as possible mechanisms causing the variations of the spore wall configurations. A membrane-like structure that covers the "rodlet" patterns and which hinders spore …

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A Study Of Folic Acid Dependent Reactions In Bovine Brain, Dillard Spencer Broderick Aug 1969

A Study Of Folic Acid Dependent Reactions In Bovine Brain, Dillard Spencer Broderick

Theses and Dissertations

The enzymatic interconversion of serine to glycine and N5, N10-methylene tetrahydrofolate to N5 -methyl tetrahydrofolate have been studied in a cell-free system derived from bovine brain. A partial purification of serine transhydroxymethylase and N5, N10 -methylene tetrahydrofolate reductase has been achieved by ammonium sulfate fractionation, protamine sulfate fraction, and by various column chromatography procedures. The two enzymes studied catalyze sequentially the reductive transfer of the hydroxymethyl group of serine to the N5 position of tetrahydrofolate forming N5 -methyl tetrahydrofolate. The products of these reactions were assayed by the incorporation of C14 from a one-carbon precursor i.e., L-beta-(C14)-serine, or N5 -methyl …

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Comparative Effects Of Carbon Dioxide On Coccidian Oocysts From Five Different Host Species, Thomas David Bunch Aug 1969

Comparative Effects Of Carbon Dioxide On Coccidian Oocysts From Five Different Host Species, Thomas David Bunch

Theses and Dissertations

Excystation, as applied to the coccidia, is the process by which sporozoites are released from sporocysts and oocysts. Although this process has long been a subject of interest and study, there still remains considerable disagreement among investigators as to the mechanism by which the process occurs and the factors which are involved.

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A Study Of Conifer Invasion Into Meadows Surrounding Small Lakes And Ponds In The Trial Lake Region Of The Western Uinta Mountains, David Harvey Firmage Aug 1969

A Study Of Conifer Invasion Into Meadows Surrounding Small Lakes And Ponds In The Trial Lake Region Of The Western Uinta Mountains, David Harvey Firmage

Theses and Dissertations

The object of this study was to determine whether or not Lodgepole pine is successfully invading meadows near ponds in the western Uinta Mountains as a preliminary step to the invasion of the Spruce-Fir climax forest. Line transects were established at three sites near Trial Lake extending from forest to wet meadow. Along these transects the soil was studied to determine percent organic matter, pH, depth to mineral soil, and texture. Also the depth of the water table was measured and the topography plotted. The age and size of the trees along the transect was determined, and the extent of …

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Phylogenetic Relationships Of Purshia Tridentata And Cowania Mexicana, Stewart C. Sanderson Aug 1969

Phylogenetic Relationships Of Purshia Tridentata And Cowania Mexicana, Stewart C. Sanderson

Theses and Dissertations

Because of the greatly increased supply of genetic variation which it provides, introgression is of great importance in determining both the rate and the direction of evolution. Hybridization between the genera Cowania and Purshia provides an excellent model for demonstrating the various products which might be expected from introgression. The present study is an attempt to further investigate phylogenetic relationships of Cowania mexicana and Purshia tridentata by use of cytological and biochemical techniques.

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The Identification Of A Germination Factor For Basidiospores Of Psilocybe Mutans, Neal K. Van Alfen Jul 1969

The Identification Of A Germination Factor For Basidiospores Of Psilocybe Mutans, Neal K. Van Alfen

Theses and Dissertations

Basidiospores of the Basidiomycete Psilocybe mutans have been found to germinate only in the presence of water extracts of animal dung. The chemical nature of the factor present in the dung that induces germination is not known, nor has it ever been isolated· Experiments showed that extracts of bile salts cause the basidiospores to germinate, indicating that since bile salts are found in dung, they may be the factor which stimulates the spores to germinate. Investigations of the properties of the factor in dung show that the factor has solubility properties that are similar to those of the bile acids. …

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Inhibition Of Asexual Reproduction In Planaria, Lewis Hafen Leavitt Jul 1969

Inhibition Of Asexual Reproduction In Planaria, Lewis Hafen Leavitt

Theses and Dissertations

Asexual reproduction in the decapitated planaria, Dugesia dorotocephala, is inhibited by an extract of homogenized heads of the same or closely-related species. Decapitated planaria allowed to regenerate have reproduced asexually over 80% of the time, while those that have been cultured in a suspension of head homogenate have had asexual reproduction inhibited to less than 10%. The substance that inhibits asexual reproduction is heat labile. It requires a concentration of 2.0 heads/ml that contains .13 mg protein/ml to effectively inhibit asexual reproduction. A similar concentration of head homogenate from the related planaria, Dugesia tigrina, also contains the inhibitory substance. Head …

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New Records And Species Of Neotropical Bark Beetles (Scolytidae: Coleoptera), Stephen L. Wood Jun 1969

New Records And Species Of Neotropical Bark Beetles (Scolytidae: Coleoptera), Stephen L. Wood

Brigham Young University Science Bulletin, Biological Series

No abstract provided.

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Front Matter, Vol. 10 No. 3 Jun 1969

Front Matter, Vol. 10 No. 3

Brigham Young University Science Bulletin, Biological Series

No abstract provided.

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End Matter, Vol. 10 No. 3 Jun 1969

End Matter, Vol. 10 No. 3

Brigham Young University Science Bulletin, Biological Series

No abstract provided.

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End Matter, Vol. 10 No. 2 Jun 1969

End Matter, Vol. 10 No. 2

Brigham Young University Science Bulletin, Biological Series

No abstract provided.

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